TW201239190A - Engine and the vehicles/ships equipped thereof - Google Patents

Abstract

An engine includes: an air exhaust device having an air exhaust outlet for introducing exhaust gas from a combustion chamber; an air supply device for supplying air. The air exhaust outlet is disposed with a convergent portion, a divergent portion and a branch portion. The branch portion allows the impact wave propagated in the downstream direction from more upstream than the said divergent portion to branch off from said air exhaust channel for making said impact wave to propagate to said air exhaust channel again. The air supply device includes: a first channel, having a first reed valve to allow air flow to pass from the direction of upstream to downstream, and the downstream end connected to said air exhaust outlet is more upstream compared to said divergent portion; a second channel, having the upstream end connected to said first outlet is more upstream compared to said first reed valve. Said air exhaust device allowing the exhaust gas to pass through said convergent portion is constituted by an impact method of the impact wave that propagated in said branch portion between said branch portion and said divergent portion.

Description

201239190 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to an engine (internal combustion engine) and a vehicle and a ship therewith. [Prior Art] It is known to include a catalyst for purifying exhaust gas and an engine for supplying a secondary air supply device (Sec〇ndary Air Supply System) to the exhaust passage (lnternai c〇mbusti〇n, internal combustion engine). For example, in the engine of Patent Document 1, a three-way catalyst is disposed in the exhaust passage. The secondary air supply means is connected to the exhaust passage so as to supply secondary air to the upstream and downstream of the catalyst, respectively. Secondary air refers to air that is not supplied through the combustion chamber of the engine. The catalyst mainly functions as a reduction catalyst for reducing ruthenium, but it also functions as an oxidation catalyst. #, Supply to the downstream of the catalyst: the gas is temporarily flowing into the catalyst and then flows downstream by the pulsation of the exhaust gas. At this time, the catalyst also functions as an oxidation catalyst for oxidizing c〇 and thc, and purifies the ruthenium, CO, and THC in the exhaust gas discharged from the engine. The secondary air supply to the engine of the patent (1) is also configured to supply secondary air to the upstream of the catalyst. The reason for this is that when the air-fuel ratio to the engine is set to be high when the vehicle is operated at a high speed, the amount of C〇 and THC contained in the exhaust gas is increased. At this time, the catalyst can be mainly used as a medium for causing c〇 to be oxidized by supplying an artificial hole to the upstream of the catalyst. Emulsification In Patent Document 1, two methods are disclosed as a method of supplying secondary air to the downstream of the catalyst. One method is equipped with a reed and uses the pulsation of the exhaust in the exhaust passage of 154997.doc 201239190. Another method is to provide an air pump instead of a reed valve to forcibly supply secondary air to the exhaust passage. [Prior Art] [Patent Document 1] [Patent Document 1] JP-A-2006-220019 SUMMARY OF THE INVENTION [Problems to be Solved by the Invention] The above is to supply the secondary air to the downstream of the catalyst. Two methods. The method of using the exhaust pulsation is different from the method of using the air pump, and there is no need to drive the pump, so the engine output loss is small. However, this method has the following problems. When the engine is operated at high speed or high load, the average dust force in the exhaust passage becomes high. Further, in the portion of the exhaust passage which is further downstream than the catalyst, the amplitude of the exhaust pulsation is small due to the resistance of the catalyst. The more the engine becomes a two-speed or high-load state, the greater the resistance generated by the catalyst. That is, especially when the engine is operated at a high rotation speed or a high load state, the average pressure in the exhaust passage is 胄胄, and the amplitude of the exhaust pulsation becomes small. As a result, a large negative pressure cannot be generated in the exhaust passage downstream of the catalyst. Thus, especially when the engine is operated at a high speed or a high load state, it is not possible to supply a sufficient amount of secondary air to the exhaust passage which is more downstream of the catalyst. In another aspect, the method of using the air system can supply secondary air even when the engine is operated at a high rotational speed or a high load state. However, the higher the engine is at high speed or high load, the greater the load on the air pump. Because it is driven by the engine. Xuan Erqi Pump's, the engine becomes higher speed or high load, the greater the loss of engine output 154997.doc 201239190. The inventors of the present invention have found that the shock wave n which is propagated downstream in the exhaust passage when the exhaust port is opened is considered to be capable of supplying air even under a high load state if a negative pressure is generated after the shock wave is applied. However, the shock wave is generated near the exhaust port and attenuates and disappears as it propagates downstream. Therefore, it cannot be used to generate a negative pressure downstream of the catalyst. Thus, the inventors of the present invention considered generating other new shock waves in the exhaust passage to generate a new negative pressure. The principle of a commonly known gradual-divergent nozzle (c〇nvergent_Divergent N〇zzle), commonly known as Lawr's mouth, is applied to an engine including a secondary air supply device. The nozzle includes a tapered portion that has a smaller cross-sectional area of the flow path toward the downstream side of the flow path, a diverging portion that has a larger cross-sectional area of the flow path downstream of the tapered portion, and a throat portion that is located Between the tapered portion and the diverging portion. When the pressure of the tapered portion P0 and the pressure of the diverging portion? The pressure ratio (p/p〇) is less than the critical pressure ratio (Ο-1 Rati〇. If it is about 0.528 for air), the flow velocity of the fluid in the diverging portion exceeds the speed of sound β, thus the shock wave of the production line. The cross-sectional area of the flow path at the downstream end is smaller than the tapered portion of the cross-sectional area of the flow path at the upstream end, and the flow path of the downstream end of the exhaust passage disposed downstream of the tapered portion is larger than the flow path of the upstream end. Scaling area of the scraping area. However, if the tapered portion and the divergent portion are provided only in the exhaust passage, the ratio of the force of the tapered portion to the dust force of the diverging portion ((10)) cannot reach the ratio of force (4), and thus cannot be produced. New shock wave. As a result of further research on the engine by the inventor of the present invention, it was found that 154997.doc 201239190 shock wave propagating downstream in the exhaust passage when the exhaust port is opened, at this time, exhaust gas flowing from the combustion chamber to the exhaust passage Higher speed spread. Further, the inventors paid attention to the difference between the shock wave velocity and the exhaust gas velocity, and considered the structure for increasing the pressure P0 of the tapered portion. This configuration includes causing the preceding shock wave to temporarily branch from the exhaust passage and return to the branch portion of the exhaust passage again. A new shock wave is generated in the diverging portion by increasing the pressure P0 of the tapered portion. As a result, a negative pressure is generated downstream of the shock wave, i.e., further upstream of the flared portion. Further, the inventors of the present invention have considered a structure in which air is supplied to the negative pressure generated upstream from the gradually expanding portion. The configuration includes a second channel connected further upstream of the diverging portion of the exhaust passage and a second passage connected to the second channel. An embodiment of the present invention provides an engine using the configurations. That is, the engine according to an embodiment of the present invention includes: a combustion chamber formed with an exhaust port; an exhaust valve that opens and closes the exhaust port; and an exhaust device i that is guided from the combustion chamber through the exhaust An exhaust passage of the exhaust gas discharged from the port; and an air supply device that supplies air. The venting device includes: a tapered portion disposed in the exhaust passage, and a cross-sectional area of the flow path at the downstream end is smaller than a cross-sectional area of the flow path at the upstream end; and a diverging portion that is disposed above the tapered portion Is the downstream, and the downstream end of the flow path at the upstream end of the flow path sectional area; and the branch portion, which will be higher than the exhaust gas flowing from the combustion chamber to the exhaust passage when the upper opening is opened = degree in the above exhaust The shock wave propagating downstream in the channel branches from the exhaust channel further upstream and propagates the impact (4) 154997.doc 201239190. The air supply device includes: an imaginary piece having a flow of air passing from the upstream end toward the downstream end upstream of the diverging portion of the exhaust passage, and a connection of the I swim end to the first passage Above! The reed valve is further downstream. Further, the exhaust device is configured such that exhaust gas flowing from the combustion chamber to the exhaust passage passes through the tapered portion, and propagates between the branch portion and the diverging portion and in the branch portion The shock wave collides, thereby increasing the pressure of the exhaust gas at the tapered portion, and generating a new (four) wave by passing the increased exhaust gas through the diverging portion. Further, the air supply device is configured to introduce air into the exhaust passage that is generated in the exhaust passage upstream of the diverging portion by the newly generated shock wave. The first passage is configured to supply the introduced air to the second passage by a positive pressure generated in the exhaust passage upstream of the diverging portion. According to this configuration, the "previous shock wave is temporarily branched in the branch portion and then returned to the exhaust passage again. Thereby, the branch portion can delay the shock wave in time", so that the shock wave can collide with the exhaust gas in the exhaust passage. Therefore, the pressure of the exhaust gas can be increased. The exhaust gas is further increased in pressure by passing through the tapered portion, and the pressure ratio of the pressure of the tapered portion and the pressure of the gradually expanding portion (Ρ/Ρ0) is easily reached. The pressure ratio, that is, when the high-pressure exhaust gas passes through the diverging portion, a new shock wave (a shock wave different from the shock wave generated when the exhaust port is opened) is generated. The upstream of the new shock wave, that is, upstream of the diverging portion The larger negative pressure can be used to introduce secondary air from the upstream air end of the i-channel 154997.doc 201239190 secondary air system to the air outside the engine in the first passage through the combustion chamber. In the exhaust passage which is more upstream than the gradually expanding portion, the positive pressure is alternately generated by the exhaust pulsation. The amplitude of the exhaust pulsation is larger due to the larger and more upstream. Become bigger by the influence of pressure The secondary air that is introduced into the first passage when the negative pressure is generated is extruded from the first passage and supplied to the second passage when the positive dust is generated. The downstream end of the second passage may also be connected to the row. The air passage, that is, the secondary air extruded from the i-th passage may be supplied to the exhaust passage via the second passage. The configuration is such that when the catalyst is disposed downstream of the diverging portion in the exhaust passage It is especially advantageous to use a large negative pressure generated by a new shock wave and a positive pressure generated by the pulsation of the exhaust gas, and even at a high rotational speed or a high load state, it can be further downstream to the catalyst. The secondary air is supplied into the exhaust passage. The positive pressure and the negative pressure generated at this time utilize the energy of the exhaust gas, thereby reducing the loss of engine output. The above, or other objects, features and effects of the present invention may be utilized by The following description of the embodiments of the present invention will be apparent. [Embodiment] As a result of active research, the inventors of the present invention have conceived that the principle of a tapered-smoothing nozzle can be utilized to utilize a previously unused method as follows. Supply sufficient The secondary air. The method is as follows: (1) Branching the shock wave that propagates earlier than the exhaust gas. (2) Delaying the shock wave of the branch to collide with the exhaust gas to increase the pressure of the exhaust gas. The exhaust gas with increased pressure is accelerated to the 154997.doc -10· 201239190 supersonic speed and the impact of the production line ^(4) generates a negative pressure in the exhaust passage which is more upstream than the diverging portion. (5) Negative pressure, introducing secondary air into the first passage of the secondary air supply device connected to the upstream portion of the _ portion. (6) utilizing the positive pressure generated in the exhaust passage further upstream than the gradually expanding portion The second air is supplied to the second passage of the secondary air supply device. <First Embodiment> The following describes the embodiment of the present invention in detail. The following description will be given of t, "upstream" and " “Downstream” refers to the upstream and downstream of the flow direction of the exhaust gas or secondary air, respectively. Fig. 1 is a cross-sectional view showing the configuration of an engine according to a first embodiment of the present invention. The engine 1 includes: a gas rainbow body 3; a gas cap 4 which is placed at one end of the gas red body 3; and a piston 5 which reciprocates in the gas body 3. A combustion chamber 10 is formed inside the gas red body 3 and the cylinder head 4. More specifically, the combustion chamber 1Ge piston 5 is coupled to the crankshaft via the connecting rod 15 by the inner wall of the cylinder block 3, the inner wall of the cylinder head 4, and the surface of the piston 5 (the surface opposite to the gas siphon cover 4). 16. The crankshaft 16 is housed in a crank case 17 that is coupled to the cylinder block 3. The reciprocating motion of the piston 5 is transmitted to the crankshaft 16 by the link 15, whereby the crankshaft 铋 is turned. The engine 1 is a 4-cycle gasoline internal combustion engine. Engine i is a single cylinder engine. Engine 1 can be an air-cooled engine or a water-cooled engine. The cylinder head 4 is formed with a downstream portion of the intake passage 6 and an upstream side of the exhaust passage #7a. The cylinder head 47 is provided with an intake valve 8 that opens and closes the intake port 8a, and opens and closes the exhaust port 9a. An exhaust valve 9; and a valve device (not shown) for driving the intake valve 8 and the exhaust manifold 9. In the present embodiment, one downstream of the downstream portion 6a of the intake passage 6 and the upstream (four) of the exhaust passage 7 is provided for each of the illuminating passages 154997.doc 201239190. However, the air port 8a, the intake valve 8, the exhaust port 9a, and/or the exhaust valve 9 may be provided in plural numbers with respect to each of the combustion chambers. An injection fuel 贳 态 2 is mounted on the cylinder head 4. The illustration is omitted. The ignition head is provided on the cylinder head 4. The throttle valve U is disposed further upstream of the downstream portion 6a of the intake passage 6 than the lower portion. The lang valve, i, may also be mechanically coupled to an operating member operated by an operator (e.g., coupled via a cable) ... or may not be a mechanical combination, but the throttle valve 丨i is electronically controlled by a motor. The engine 1 in turn includes an exhaust device 50. The exhaust device 5 includes: an i-th exhaust pipe 51 connected to the cylinder shark 4; a second exhaust gas 52 connected to the i-th exhaust pipe η: and a second exhaust pipe 52 connected thereto 3 exhaust pipe μ. The first exhaust pipe 51 is attached to the cylinder head 4 by bolts 12. The third exhaust pipe is installed inside to form an exhaust chamber 55. The exhaust device 50 has an exhaust passage 7 connected to the outside from the upstream portion via the exhaust chamber 55. The exhaust channel 7 is configured with the first! Catalyst 21 and second catalyst 22. The second catalyst Μ is disposed downstream of the P catalyst 21. A space is provided between the i-th catalyst 21 and the fourth (fourth) rib. A muffler (not shown) is connected downstream of the discharge chamber 55. The exhaust gas that has flowed into the inside of the exhaust chamber 55 is discharged to the outside through the above-described muffler. An oxygen concentration sensor for detecting the amount of oxygen in the exhaust gas is provided in the exhaust chamber 55. The engine 1 includes an ECU (Eiectr〇nicaIly Controlled Unit) 2 as a control device. The ECU 2 controls the fuel injection amount of the injector 2 or the ignition timing of the ignition spark I54997.doc 201239190 according to the rotation speed of the engine i, the opening degree of the throttle valve 、, or the signal detected by the oxygen concentration sensor 19. Wait. The ECU 20 controls the fuel injection amount of the injection number 2 such that the second combustion ratio of the mixture gas sucked into the engine 1 becomes a stoichiometric. A branch pipe 30 is provided at an upstream portion of the first exhausting officer 51. One end of the branch pipe 3 is connected to the open end of the first exhaust pipe 51, and the other end is a closed closed end. The closed end forms a reflection portion 31b that reflects a shock wave to be described later. The branch pipe 30 may also be integrally formed in the i-th exhaust pipe 51. Further, the branch pipe may be formed separately from the first exhaust pipe 51 and fixed to the second exhaust pipe 51. For example, the first exhaust pipe 51 and the branch pipe 30 may be welded together, or may be fixed together by a fastening member (not shown) such as a screw or a rivet. The closed end of the branch pipe is formed in such a manner that the flow path sectional area is larger than the open end. The shape of the branch pipe 30 is not limited to the shape shown in FIG. That is, the cross-sectional area of the flow path at the closed end of the branch may be equal to the cross-sectional area of the flow path at the open end thereof or smaller than the cross-sectional area of the flow path at the open end. A branch portion 31 is formed inside the branch pipe 30. Branch portion 31

It is connected to the open end of the exhaust passage 7, and the other end is a closed end. The branch portion L inlet 31a (that is, a portion that communicates with the exhaust passage 7) is formed as follows, such that the shock wave propagating inside the exhaust passage 7 is also propagated through the inside of the branch portion 31. . The center line of the flow path section of the map] The heart line 2 is the entrance of the heart of 31.糸 曰 曰 曰 曰 曰 ( ( ( ( 流 流 流 流 流 流 流 流 流 流 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 The tapered-divergent nozzle 4 is known as a delta nozzle. Flow through the exhaust - from the subsonic speed to 154997.doc -13- 201239190. The gradual and progressive expansion of the spray is completed. The tapered portion 41 is connected to the lower portion of the throat portion 42 and the gradual portion toward the downstream. The gradually expanding part 43 is a part of the flow path that gradually increases with the wide area, and the section of the flow path is gradually increased. The throat 42 is a new part of the configuration, and the cross-sectional area of the flow path is the smallest: :: M1 and gradually The exhaust passage 7 of the two T exhaust device 50 between the expansion portions 43 is supplied to the air two-artificial enthalpy supply device 70. The secondary air &amp;# π # L human two-roll supply device 7 includes: a reed valve 74 (check valve): a second secondary air supply tributary valve 々μ-shaped rolling supply pipe 76; and a second secondary air supply pipe 77 connected to the first secondary empty rolling supply pipe 76. The reed valve 74 is combined At the upstream end of the second air supply pipe %, the downstream end of the second air supply pipe 76 is connected between the branch pipe 3〇 in the first exhaust pipe and the tapered/diverging nozzle 40. The secondary air supply pipe % is connected to the air cleaner 78 via the reed valve 74 and the air amount control valve 75. The reed valve 74 prevents the exhaust gas from flowing inward from the second secondary air supply pipe %. The reed valve 74 It is constituted by opening a negative pressure by the exhaust passage 7 and flowing the air downstream of the i-th secondary air supply pipe 76. The valve 75 is for adapting the amount of secondary air to the operating state of the engine cymbal. The air amount control valve 75 includes an actuator, a servo motor or a solenoid, etc., which is powered by an intake negative pressure or the like. When the degree of opening of the valve 75 is controlled by the ECU 20, when the opening degree of the throttle valve is less than a specific angle, the ECU 20 closes the air amount control valve 75 or reduces the opening degree of the throttle valve 11. The specific angle is The ECU 20 increases the opening degree of the air amount control valve 75 when the opening degree of the throttle valve 11 is larger than the specific opening degree. Thus, 154997.doc 14 201239190 air volume control valve 75 corresponds to the opening degree of the above-described throttle valve u to increase or decrease the opening degree. By including the air amount control valve 75, it is possible to supply the secondary air to the exhaust air supply if 7 without excessively low. The air amount control valve 75 may be omitted. The upstream end of the second primary air supply pipe 77 is connected to the reed valve at its downstream end with respect to the second secondary air supply pipe 76. The downstream end of the second secondary air supply officer 77 is connected between the i-th catalyst 2ι and the second catalyst 22 in the second exhaust pipe 52. More detailed! The downstream end of the second secondary air supply pipe is connected to the second exhaust pipe 52 at a position closer to the first catalyst 21 than the second catalyst 22, and the primary air supply device 70 includes the i-th channel 71 and The second passage 72. The first passage 71 is a passage from the reed valve 74 to the exhaust passage 7, and is a passage formed by the first secondary air supply pipe 76. The first passage 71 is connected to the reed valve. 74. The population of the branch portion 31 of the exhaust passage 7 is 3 (four) between the gradually expanding portions a. The second passage 72 is the passage of the exhaust passage 7 from the i-th passage 71 to the second exhaust button and is borrowed The passage formed by the second secondary air supply pipe 77. That is, the second passage 72 is connected to the second passage 71, the portion between the first catalyst 21 and the second catalyst 22 of the exhaust passage 7. The i-th passage "Upstream" and "downstream" refer to the connection portion 71b of the air reed valve 74 (upstream of the i-th channel 71) to the exhaust passage 7, respectively (hereinafter also referred to as "the downstream end 7" ") upstream and downstream related to the direction of flow. The "upstream" and "downstream" of the second channel are the connection portions 72b of the air from the connection portion 72a (hereinafter also referred to as "upstream end") of the passage 71 to the exhaust passage 7, respectively (hereinafter also referred to as As the "downstream end 72b"), the direction of the flow is related to 154997.doc •15- 201239190 swim, downstream. Here, when the gas flows from the reed valve 74 to the second passage 72 and the connection portion 72a of the first passage 71 through the first passage 71, the amount of energy (energy loss) of the gas loss is set to L1. Further, when the gas flows through the second passage 72 from the downstream end 72b to the upstream end 72a of the second passage 72, the magnitude (energy loss) of the gas loss energy is set to L2. If these are compared, the first and second passages 71, 72 are designed so that the energy loss in the L1 &lt; L2 is synonymous with the pressure loss of the gas in the flow path. When the energy loss of the gas in the flow path from the connection portion 72a of the second passage 72 to the connection portion 71b of the exhaust passage 7 is set to L3, L1+L3&lt;L2+L3 can. When the energy loss from the reed valve 74 in the first passage 71 to the flow path 61 of the connecting portion 71b of the exhaust passage 7 is L11, L11 = L 1 + L3. On the other hand, if the energy loss from the downstream end 72b of the second passage 72 to the upstream end 72a and the flow path 62 passing through the first passage 71 to the downstream end 711 is L12', then L12 = L2 + L3. Therefore, the first and second passages 71 and 72 may be designed such that L11 &lt; L12. This relationship of energy loss can be verified, for example, in the following manner. That is, the second passage 72 is closed (for example, closed at the downstream end 72b), and the flow coefficient u of the air measured at the downstream end (connecting portion 71b) of the flow path 61 is flowed through the flow path 61. On the other hand, the first passage 71 is closed (for example, closed at the upstream end 71a), and the flow path "flows air", and the downstream end of the flow path 62 (the connection portion 71b) measures the flow coefficient to 2. In this case, if kl is satisfied. K2 satisfies L11 &lt; L12. It is sufficient to use the following method for flowing air in the flow paths 61 and 62. The i-th method is to connect the upstream ends of the flow paths 61 and 62 to the flow path 61, Air transport within 62 • 16· 154997.doc

201239190 Method. The second method is a method of connecting a pump to the downstream ends of the flow paths 61, 62 and sucking air from the flow paths 61, 62. These components may also be included in the flow path 61 when the energy loss of the air volume control valve 75 and/or the air cleaner 78 is negligible. In this case, the flow path 61 is a flow path from the large fluorine open position to the connection portion 71b. Further, in the connection portion Ma where the gas flows from the open position of the atmosphere to the second passage 72 and the second passage", the loss l 1 is the magnitude of the gas loss energy. The coefficient is the air flowing through the private passage. The ratio of the flow rate to the theoretical air amount determined by the actual opening area and the pressure difference is obtained by dividing the actual air flow rate by the theoretical air flow rate. Examples of energy loss when the gas flows through the pipeline include the wall surface The loss caused by friction, the loss of the inlet or outlet of the pipeline, the loss caused by the bending of the pipeline, the loss caused by the change of the cross-sectional area of the flow path, and the loss caused by the valve, etc. The loss caused by the loss of the cross-sectional area becomes larger or smaller, and the surface of the wall whose surface area is slowly becoming larger or smaller becomes thicker and coarser, the length of the pipeline is longer, and the pipeline is called The greater the loss caused by the friction of the wall surface. The diameter of the pipe is divided by the larger the ratio of the radius of curvature and the larger the angle of the f curve, the greater the loss caused by the bending of the pipe. Cheng Zhizhi will be based on the valve The class or degree of opening differs and needs to be determined by means of f ▲ W 。. In terms of the loss of the reed valve, for example, the pressure difference between the reed valve and the downstream and downstream can be determined. The relationship between the opening degree of the steam valve (the profile of the flow path + % Daoshan r丄V) and the flow rate of the scallop, and based on this, the relationship between the pressure difference and the loss coefficient is derived. Tu 154997.doc 201239190 Figure 2 is common Schematic diagram of the tapered and divergent nozzle. The flow path section (10) at the upstream end of the tapered portion, the cross-sectional area A2 of the flow path of the throat portion 42, and the cross-sectional area of the flow path at the downstream end of the divergence and the downstream end are illusory A1&gt;A2 , A2 &lt; A3 relationship. The flow of the throat portion 42 (4)_A2 is the same as the cross-sectional area of the downstream material of the tapered material 41 and the upstream end of the diverging portion 43. In the present embodiment, the flow path cross-sectional areas of the progressive (four) Μ and the dilating portion 43 are changed in a fixed ratio along the flow direction. However, the tapered portion 41 and the diverging portion 43 may have a shape in which the flow path sectional area is changed stepwise by the nozzle of the other (10) m mm. Further, the inner surface of the nozzle can be formed into a smooth curved surface. The tapered-swelling nozzle 40 is formed to satisfy the conditions shown in the following equations (2) and (2). The Mach 1 (i.e., the speed of sound) is reached by the flow rate of the exhaust gas flowing into the throat portion 42, and the exhaust gas can be accelerated to the supersonic speed in the dip portion 43. [Number 1] dM _ 八,. dx l~M2 ^ [Number 2] Λ Ξ Μ γ Μ2 ί4/) 1 dA ——---- L 2 J 2 [d) A dx (2) Equation (1) It is accompanied by the relationship between the shape of the exhaust pipe and the Mach number in one-dimensional flow of viscous friction. The equation (2) does not count eight of the equations (1). In this case, 'Μ denotes the Mach number, A denotes the sectional area of any section of the exhaust pipe, 〇 denotes the diameter of the tube of any of the above sections, γ denotes the specific ratio, ...m, X does not flow -18- 154997.doc

201239190 The distance in the moving direction, f is the coefficient of friction. As shown in Fig. 2, the total pressure (Full Pressure) upstream of the throat portion 42 is set to P, and the static pressure (Static Pressure) downstream of the throat portion 42 is set to P. As shown in Fig. 3, when the ratio Ρ/Ρ0 of the pressures is less than the critical pressure ratio = 0.528 (point C in Fig. 3), the velocity at the throat 42 becomes the speed of sound (Mach 1) or more, and as a result, it is gradually expanded. The speed of the portion 43 becomes supersonic. Therefore, if the total pressure P 提升 is raised so that p / p 〇 is smaller than the critical pressure ratio, the supersonic flow can be formed in the tapered - diverging nozzle 4 。 . When the flow velocity of the tapered-smoothing nozzle 40 becomes supersonic, a shock wave 35b that propagates downstream of the diverging portion 43 and an expanding wave 35c that propagates upstream (see Fig. 6) are generated. The fluid in the space between the shock wave 35b and the expansion wave 35c rapidly expands, so that the pressure of the exhaust gas flowing through the exhaust passage 7 is lowered. As a result, the temperature of the exhaust gas can be rapidly reduced by the effect of Adiabatic cooling caused by Adiabatic Expansion. Further, as a result of active research by the inventors, it has been found that this state can be realized by combining the tapered-divergent nozzle 40 and the branch portion 3A. Next, the principle in which the exhaust gas is in a state where the pressure is low in the exhaust passage 7 and the temperature is low will be described with reference to FIGS. 4A to 4C. 4A to 4C schematically show the engine 1 including the exhaust unit 5〇. In Figs. 4 to 4C, the same or equivalent components as those shown in Figs. 1 and 2 are attached with the same reference numerals. As shown in Fig. 4A, if the exhaust port 9a is opened by the exhaust stroke of the engine 1, the high-pressure exhaust gas 36 is ejected from the combustion chamber 1 () through the exhaust port to the exhaust passage 7 above. At the time when the exhaust gas σ 9a starts to open, the pressure difference between the combustion chamber 1〇 and the upstream portion of the 154997.doc -19-201239190 exhaust passage 7 is large, so the speed of the exhaust gas reaches the speed of sound, thereby arranging The shock wave 35 is generated in the upstream portion of the gas passage 7. As the exhaust port 9a is opened largely, the amount of exhaust gas flowing out to the upstream portion of the exhaust passage 7 increases, but the speed of the exhaust gas becomes slow. Further, the exhaust gas is decelerated as it advances toward the upstream portion 7a of the exhaust passage 7. As shown in Fig. 4A, the shock wave 35 propagates from the upstream portion 7&amp; of the exhaust passage 7 to the inside of the third exhaust pipe 51, and then propagates toward the downstream at a constant speed. On the other hand, the exhaust gas 36 travels behind the exhaust passage 7 at a lower speed than the shock wave 35. As shown in FIG. 4B, the shock wave advancing inside the i-th exhaust pipe 51 is divided into a shock wave propagating in the exhaust passage 7 and a shock wave propagating in the branch portion 31 when passing through the inlet 31a of the knife branch portion 31, and Each of the exhaust waves 7 and the branch portion 31 travels independently. The shock wave that advances in the exhaust passage 7 is attenuated and disappears by the tapered-smoothing nozzle 40. On the other hand, the shock wave 35 that has advanced in the branch portion 31 is reflected by the reflection portion 31b of the branch portion 31 and is reversed to the branch portion 31 to return to the exhaust passage 7. As shown in FIG. 4C, the branch portion 31 is set such that the time during which the reflected shock wave 35 returns from the branch portion 31 to the exhaust passage 7 is the same as or later than the time at which the high-pressure exhaust gas 36 reaches the center of the inlet 3ia of the branch portion 31. The length. Therefore, the shock wave 35 collides with the exhaust gas 36 in the exhaust passage 7 which is further upstream than the gradually expanding portion 43 and at the inlet 31a of the branch portion 3A or downstream thereof. Thereby, the total pressure upstream of the throat 42 of the tapered-divergent nozzle 40 can be increased. As a result, a state in which the pressure ratio Ρ/Ρ0 is smaller than the critical pressure ratio can be achieved so that the supersonic flow can be formed in the tapered-smoothing nozzle 40. Fig. 5 is a schematic view showing the exhaust path of the shock wave and the exhaust path of the exhaust gas 154997.doc -20· 201239190 channel 7 and the like. The distance (flow path length) from the center of the exhaust port % to the center line 流 of the flow path section of the branch inlet 31a is u, and the center line 丫 of the flow path of the exhaust passage 7 and the reflection portion m The distance (flow path length) is set to Ls. Further, the speed of the exhaust gas 36 is set to %, and the propagation speed of the shock wave 35 is set to Vs. The time T1 from the time when the exhaust port is opened until the exhaust gas reaches the inlet 3 la is expressed by the formula (3). Further, the time T2 from when the exhaust port % is opened until the shock wave 35 is reflected by the reflecting portion 31b and reaches the center line ¥ of the exhaust passage 7 is expressed by the formula (4). T1 .................. T2==(Le+2Ls)/V .......(4) If T1ST2, the reflected shock wave 35 and exhaust gas 36 Crash. That is, if

Le/VeS (Le+2LS)/VS, which is further upstream than the diverging portion 43 and in the inlet 31a of the branch portion 31 or the exhaust passage 7 downstream thereof, the reflected shock wave 35 collides with the exhaust gas 36. Furthermore, for convenience, for example, the maximum speed of the exhaust gas can be regarded as the above-mentioned speed Ve, or the average speed can be regarded as the above speed.

Ve. Similarly, for example, the maximum propagation velocity of the reflected shock wave 35 may be regarded as the above-described propagation velocity Vs, or the average propagation velocity may be regarded as the above-described propagation velocity Vs. As shown in Fig. 5, the distance (flow path length) from the center line X of the flow path section of the branch inlet 3 1 a to the upstream end of the diverging portion 43 is Ld, and the self-venting port 9a is opened to be closed. The time is set to tv. The time T3 from when the exhaust port 9a is opened until the end of the exhaust gas 36 reaches the upstream end of the diverging portion 43 is expressed by the formula (5). Further, the time T4 from when the exhaust port 9a is opened until the shock wave 35 is reflected by the reflecting portion 31b and reaches the upstream end of the diverging portion 43 is expressed by the formula (6). 154997.doc -21 - 201239190 T3=tv+(Le+Ld)/Ve.....(5) T4=(Le+2Ls+Ld)/Vs ----(6) Right T4ST3 'is in exhaust gas 36 The reflected shock wave 35 can be collided with the exhaust gas 36 before passing through the throat 42 all. That is, if (Le + 2Ls + Ld) / Vs $ tv + (Le + Ld) / Ve, the reflected shock wave 35 can collide with the exhaust gas 36 before the exhaust gas passes through the throat portion 42. If the distance γ between the center line γ of the flow path of the exhaust passage 7 and the reflection portion 3丨b is small, the attenuation of the shock wave 35 in the branch portion 31 can be suppressed. Thus, for example, the distance Ls can also be set to be smaller than the distance Le. The pressure of the exhaust gas is increased by the compression of the tapered portion 41. Further, the pressure of the exhaust gas 36 of the tapered portion 41 is further increased by the collision of the shock wave 35 with the exhaust gas 36. In this way, the total pressure P0 upstream of the inlet of the tapered-divergent nozzle 40 is increased. Therefore, the ratio of the total pressure p〇 upstream of the inlet to the downstream static pressure p of the throat is less than the critical value. The pressure is 〇528. As a result, the speed of the exhaust gas 36 reaches the speed of sound at the throat 42. Fig. 6 is a schematic view showing the patterning of a photograph obtained by photographing the inside of a tapered_smoothing nozzle by a schlieren method. The speed of sound is reached by the velocity of the exhaust gas 36, and the tapered/divergent nozzle 40 generates a new shock wave. Hereinafter, the newly generated shock wave is referred to as a traveling shock wave 35b for convenience. The traveling shock wave 351 is accelerated when passing through the diverging portion 43 of the tapered-divergent nozzle 40. When the traveling shock wave 35b is generated, the expansion wave 35c that advances in the opposite direction to the traveling shock wave 35b is generated. The traveling shock wave 3513 is accelerated in the diverging portion 43 and, at the same time, the expanding wave 35 (which travels in the opposite direction to the traveling shock wave 35b. Thereby, the pressure and temperature of the exhaust gas 36 existing between the traveling shock wave 35b and the expanding wave 35c 154997.doc • 22-201239190 "Large reduction" As described later, the exhaust gas becomes below atmospheric pressure, that is, it becomes a negative pressure. Fig. 7 and Fig. 8 show the results of the simulation performed by the inventor of the present invention. Fig. 7 shows the tapered-smoothing nozzle. The exhaust gas velocity (Exhaust Gas Velocity) and the exhaust gas pressure (Exhaust Gas Pressure) of each of the exhaust passages 7 immediately after the new shock wave 35b is generated. Fig. 8 shows that the tapered-semi-expansion nozzle 40 is more new. Exhaust Gas Velocity and Exhaust Gas Temperature of each position of the exhaust passage 7 after the shock wave 35b. When the tapered-smoothing nozzle 40 generates the shock wave 35b, the shock wave 35b is The dilating portion 43 is accelerated. As a result, as shown in Fig. 7 and Fig. 8, the flow rate of the exhaust gas rapidly increases, and the pressure and temperature of the exhaust gas rapidly decrease. Further, Fig. 7 and Fig. 8 show the flow rate of the exhaust gas. The figure shows the propagation speed of the shock wave. Fig. 7 and Fig. 8 show the simulation results of the case where the throat portion 42 of the tapered-divergent nozzle 4 is set to be long. The shock wave 35 and the exhaust gas reflected at the branch portion 31 are shown. At the time of the collision, the shock wave 35 propagates first in the throat 42 than the exhaust gas 36. At this time, adiabatic expansion occurs in the space between the waste_and the shock wave 35, resulting in a pressure drop, and therefore, the exhaust gas 36 is pulled by the shock wave 35. It is preferable to set the length of the portion of the throat portion 42 that is continuous with the same flow path sectional area according to the engine, thereby setting the length of the portion of the throat portion 42 in accordance with the engine. The timing of accelerating the shock wave, in other words, the timing of reducing the pressure and temperature of the exhaust gas. Thus, according to the engine of the present embodiment, the J right is greatly reduced] 54997.doc •23· 201239190 Exhaust gas in the exhaust passage 7 Next, the operation of the secondary air supply device 70 will be described with reference to Figs. 9A to 9C showing the results of the simulation performed by the inventors of the present invention. The secondary air supply device 70 is provided by the exhaust passage 7 The expanded portion 43 is more negatively generated by the upstream portion, and the secondary air is efficiently supplied to the portion of the exhaust passage 7 that is further downstream than the first catalyst 21. Fig. 9A shows the engine of the present embodiment. A diagram showing the relationship between the rotation angle (crank angle) of the crankshaft 16 (refer to FIG. 1) and the pressure in the exhaust passage 7 in the medium. When the exhaust gas _ is opened midway through the expansion stroke, self-combustion occurs. The chamber 10 discharges high-pressure exhaust gas into the exhaust passage 7. Therefore, as indicated by reference numeral 91, the inside of the exhaust passage 7 becomes a positive pressure. Thereafter, by the action of the tapered_swelling nozzle 40, a large negative is generated as shown by reference numeral 92 in the exhaust passage 7. Thereafter, positive pressure and negative pressure are alternately generated in the exhaust passage 7 by exhaust pulsation as indicated by reference numeral ’. Under the influence of the large negative dust generated by the action of the tapered/diverging nozzle 40, the amplitude of the exhaust pulsation becomes larger than usual. Fig. 9B shows the mass of the crankshaft 2 (refer to the rotation angle (crank angle) of Fig. 与 and the gas in the first passage 71 (gas passing through the reed valve 74) observed in the engine 1 of the present embodiment. In the case of the flow rate, the flow rate in the direction from the upstream end of the first passage 71 (the side between the cyanites 74) toward the downstream end (the side of the exhaust passage 7) is represented by a positive value. And the flow rate of the negative direction to the opposite direction. When the time is generated in the exhaust passage 7 (refer to reference numeral 92 in Fig. 9A), the inside of the first passage 71 also becomes negative, and as a result, the reed valve 74 is opened. Therefore, as shown in Fig. 9A, reference numeral 94 154997.doc •24-201239190 does not, the gas flows into the first passage 71. The self-crystallization valve 74 passes through the first passage 71 and reaches the flow path 61 of the exhaust passage 7 ( Referring to Fig. 1), the magnitude of the energy loss with the flow path 62 (refer to Fig. 1) passing through the downstream end 72b of the second passage 72 to the upstream end 72a and reaching the exhaust passage 7 is as described above. That is, the gas flows through The energy lost by the flow path 61 of the reed valve 74 is less than the energy lost when the gas flows through the flow path 62 passing through the second passage 72. The flow path having a small amount of loss is larger than the flow path having a large energy loss and the flow rate of the gas is increased. Therefore, the flow rate through the first passage 71 through the reed valve 74 is increased. That is, the flow from the second passage 72 to the first passage 71 is increased. The amount of gas increases the amount of gas flowing from the outside of the engine 1 to the first passage 71. Therefore, the outside air (secondary air) of the engine 1 containing a large amount of oxygen can be introduced into the second passage 71. The reed valve 74 is Only the configuration of the flow of the gas into the direction of one of the first passages 71 is allowed, but the flow of the gas in the opposite direction is instantaneously generated immediately after the temporary opening is closed. The negative mass flow value is shown in FIG. 9B. The reason is that after the air is introduced from the outside of the engine 1 to the i-th channel 71, when a positive pressure is generated in the exhaust passage 7 which is further upstream than the diverging portion 43 (for example, reference numeral 95 in Fig. 9A), the first passage The air in the 71 is extruded. The reed valve 74 prevents the gas from flowing from the second passage 7 toward the outside of the engine casing, so that the air in the first passage 71 is extruded to the second passage 72. Fig. 9C Indicates the rotation angle (crank angle) of the crankshaft 16 and the exhaust passage 7 A diagram showing an example of the relationship between the amount of oxygen (oxygen concentration) in each portion of the secondary air supply device 7G. Specifically, the curve 96a indicates the connection portion 72a and the exhaust passage of the second passage 72 in the second passage 71. The oxygen concentration between 7 (for example, the measurement point 154997.doc -25·201239190 a shown in Fig. 又). Further, the curve 96b indicates the vicinity of the intermediate portion of the second passage 72 (between the upstream end 72a and the downstream end 72b. For example. The oxygen concentration at the measurement point b) shown in Fig. 1. Further, the curve 96c indicates a portion of the exhaust passage 7 which is further downstream than the i-th catalyst 21 (between the i-th and second catalysts 21, 22). For example, the oxygen concentration at the point of measurement is shown in Figure (10). Further, the curve 96d indicates the oxygen concentration in the exhaust passage 7 upstream of the i-th passage connecting portion 7 (for example, the measuring point d shown in Fig. 1). When the curves 96a, 96c, and 96d are compared, it is found that the oxygen concentration in the second channel is higher than the oxygen concentration in the exhaust passage 7. This indicates that the secondary air of the engine is introduced into the first passage 71. If the curves 96b, 96c, and 96 are compared, it is known that the oxygen concentration in the second channel 72 is higher than the oxygen concentration in the exhaust channel 7. If the curve 96 &amp; The oxygen concentration in the second passage 72 is higher than the oxygen concentration in the first passage 71 (close to the exhaust passage 7). Therefore, it is known that the secondary air outside the engine i is guided to the second passage 72. When air is introduced into the second passage 72, the secondary air is supplied between the second and second catalysts 2, and thus the secondary air supply is achieved. According to the comparison of the curves 96c and 96d, The exhaust passage 7 between the first and second catalysts 2b (for example, the oxygen concentration of the measurement point shown in FIG. i, the first passage connecting portion 71b is upstream of the exhaust passage 7 (for example, (5) The lower oxygen concentration of the measurement point d) indicates that the secondary air is directed to the exhaust passage 7 further downstream than the i-th catalyst 21. Generally, the oxygen concentration (e.g., the defect b) of the second passage (four) is high. The oxygen concentration of the exhaust passage 7 (for example, the measurement point d) upstream of the i-th channel connecting portion claw is considered to be (four) for introducing the secondary air into the second passage. When this is confirmed, the purpose of supplying secondary air to the exhaust passage 7 between the first worker and the second catalysts 21 and 22 can be achieved. J54997.doc -26· 201239190 Reference numeral 97 in the curve 96c of Fig. 9C It is shown that the oxygen concentration increases substantially synchronously with the timing at which a positive pressure (which generates a positive pressure upstream of the diverging portion 43) as indicated by reference numeral 95 in Fig. 9. This indicates that the secondary air introduced into the second channel 71 passes through The second passage 72 feeds the exhaust passage 7 between the first and second catalysts 21 and 22. As described above, according to the present embodiment, a dedicated device for forcibly feeding air to the exhaust passage 7 is not used. A sufficient amount of secondary air can be supplied to a portion of the exhaust passage 7 that is further downstream than the second catalyst 21. That is, secondary air is introduced from the outside using a negative pressure generated by utilizing exhaust gas energy, and the exhaust gas is used in the same manner. The positive pressure generated by the energy sends the introduced secondary air to the downstream of the ith catalyst 2. Thus, the pumping action is realized by using the exhaust gas energy, thereby reducing the loss of the engine output. Moreover, it can be upstream of the diverging portion 43. The exhaust passage 7 generates a large negative pressure, thus The amplitude of the exhaust pulsation can be increased. Therefore, even when the engine is operated at a south speed or a load state, a large negative pressure accompanying the shock wave and a sufficient positive pressure due to the exhaust pulsation can be utilized. The secondary air is supplied to the downstream exhaust passage 7 of the first catalyst 21. Further, other pump means for supplying air may be used in combination. Even in this case, the load applied to the pump can be reduced, thereby The loss of the engine output is reduced. In this embodiment, the energy loss of the gas flowing through the machine path 61 from the upstream end 71a to the downstream end 7 lb of the first passage 71 is smaller than the flow through the downstream end 72b of the second passage. The gas of the flow path 62 of the downstream end 71b of the channel 71 is deducted. That is, the flow coefficient of the first passage downstream end 71b when the second passage 72 is closed and flows from the upstream end 7ia of the i-th passage through the 154997.doc -27·201239190 air is larger than the upstream of the connection portion of the second passage 72. The flow coefficient of the first passage downstream end 71b of the first passage 71 while flowing air through the second passage downstream end 72b. Therefore, when a negative pressure is generated further upstream than the gradually expanding portion 43, the air in the second passage 72 does not flow backward, and the secondary air can be surely introduced to the first through the reed valve 74 of the first passage 71. Therefore, when the exhaust passage 7 upstream of the diverging portion 43 becomes a positive pressure, the introduced secondary air can be sent to the second passage 72°. In this embodiment, the exhaust device The fifth and second catalysts 2, 22 are disposed in the exhaust passages 7 upstream and downstream of the downstream end 72b of the second passage 72, respectively. According to this configuration, the oxygen concentration of the exhaust gas supplied to the second catalyst 22 can be increased. Therefore, the second catalyst 21 can be mainly used as a reduction catalyst, and the second catalyst 22 can mainly function as an oxidation catalyst. When the third catalyst 21 and the second catalyst 22 are applied to the three-way catalyst, it is necessary to introduce the theoretical air-fuel ratio exhaust gas to the catalysts in order to perform both the reduction reaction and the oxidation reaction. When the second catalyst 21 is mainly used as a reduction catalyst, the fuel-rich exhaust gas may be introduced into the i-th catalyst 21. Further, when the second catalyst 22 functions as an oxidation catalyst, the exhaust gas which tends to have a lower air-fuel ratio can be introduced into the second catalyst 22. Thereby, the second catalyst 21 and the second catalyst 22 cooperate to perform both the reduction reaction and the oxidation reaction, so that harmful components in the exhaust gas can be efficiently removed. Thereby, the exhaust gas of the stoichiometric air-fuel ratio is introduced into the first catalyst 21, so that the range of the air-fuel ratio at which the harmful components can be removed can be expanded. Therefore, it is not necessary to strictly control the empty ratio. •28- 154997.doc

201239190 On the other hand, if the mixture of air-fuel ratio close to the theoretical air-fuel ratio is supplied to the combustion chamber, the amount of fuel consumed can be suppressed. If the air-fuel ratio of the theoretical air-fuel ratio is applied, the exhaust gas becomes a high temperature, so that the high-temperature exhaust gas causes the catalysts 21, 22 to marry. However, in this embodiment, the new shock wave 35b generated in the diverging portion μ generates a large negative pressure behind it. The adiabatic expansion of the exhaust gas is caused by the negative pressure. Thus, the exhaust gas can be cooled by the adiabatic cooling effect. That is, the exhaust gas is cooled before reaching the first catalyst 21. Therefore, the fuel consumption amount can be suppressed by using the air-fuel ratio close to the air-fuel ratio of the stoichiometric air-fuel ratio, and the catalysts 21, 22 can be simultaneously protected, and the poisoning of the harmful components can be achieved. Of course, even when the engine 1 is in a high load state or at a high speed, the exhaust gas can be made low pressure and low temperature, thereby protecting the catalysts 21, 22. &lt;Second Embodiment&gt; Fig. 10 is a cross-sectional view showing the configuration of an exhaust passage or the like of an engine according to a second embodiment of the present invention. In Fig. 10, the same reference numerals are attached to the corresponding portions of the respective portions shown in the above drawings. The engine 1 of the second embodiment includes a cylinder block 3, a cylinder head 4 provided at one end of the cylinder block 3, and a piston 5 that reciprocates in the cylinder block 3; the portions A combustion chamber 1〇 is formed. The cylinder head 4 is provided with an intake valve 8 that opens and closes the intake port 8a, an exhaust valve 9 that opens and closes the exhaust port 9&amp; and a valve device for driving the intake valve 8 and the exhaust valve 9. . The engine 1 further includes: an exhaust device 5; and a secondary air supply device 70 that supplies air to the exhaust passage 7 of the exhaust device 5A. The exhaust device 50 includes: a second exhaust pipe 51 connected to the cylinder head 4; a second exhaust pipe 52 connected to the first exhaust pipe 51 by J54997.doc -29-201239190; and connected to the second row The third exhaust pipe 53 of the air pipe 52; and the exhaust pipes 51, 52, 53 form an exhaust passage 7. The first catalyst 21 and the second catalyst 22 are disposed at intervals in the exhaust passage 7. A branch pipe 3〇β is provided in the upstream portion of the first exhaust pipe 51, and a tapered-divergent nozzle 4〇 is provided between the branch pipe 30 and the first catalyst 21. The secondary air supply device 70 includes a reed valve 74, a first secondary air supply pipe 76, and a second secondary air supply pipe 77 connected to the first secondary air supply pipe 76. The first secondary air supply pipe 76 forms a first passage 71 from the raft valve 74 to the exhaust passage 7. The second secondary air supply pipe 77 forms a second passage 72 from the first passage 71 to the exhaust passage 7 between the first and second catalysts 21 and 22. In this embodiment, the second reed valve 80 (check valve) is further provided in the second passage 72. The reed valve 80 is constructed such that the airflow from the upstream end 72a of the second passage 71 toward the downstream end 72b passes through the airflow in the opposite direction. The configuration other than this is the same as that of the first embodiment. Therefore, the detailed description of the second embodiment can be replaced by the drawings of Fig. 9 and Fig. 9 relating to the first embodiment. When a negative pressure is generated in the exhaust passage 7 which is further upstream than the gradually expanding portion 43, the reed valve 74 of the first passage 71 is opened, and the outside air is introduced into the first passage 71. At this time, the reed valve 80 of the second passage 72 is closed, and the air flow from the downstream end 72b of the second passage 72 to the upstream end 72a is blocked. On the other hand, when a positive pressure is generated in the exhaust passage 7 which is further upstream than the gradually expanding portion 43, the reed valve 74 of the first passage 71 is closed, and the reed valve 8 of the second passage 72 is opened. Thus, the secondary air introduced into the i-th channel 71 passes through the second passage 72 and is sent to the exhaust passage 7 downstream of the first catalyst 21. Thus, the secondary air can be supplied to the exhaust passage 7 downstream of the first catalyst 21 by the action of the negative pressure and the positive pressure generated in the passage 7 of the exhaust gas 154997.doc -30- 201239190. Further, the reed valve 80 disposed in the second passage 72 can reliably suppress the reverse flow of the air in the second passage 72, so that the secondary air can be efficiently supplied. As described above, according to this embodiment, the flow of the air in the second passage 72 is restricted from the upstream end toward the downstream end, that is, the reverse flow of the secondary air can be prevented. Therefore, when a negative pressure is generated upstream of the diverging portion 43, secondary air can be surely introduced from the upstream end of the first passage 71, and when a positive pressure is generated upstream of the diverging portion 43, The second air is supplied to the first and second catalysts 21 and 22. &lt;Third Embodiment&gt; FIG. 11 is a cross-sectional view showing the configuration of an exhaust passage or the like of the engine according to the third embodiment of the present invention. In Figure 11, the above figure! Corresponding parts of the various parts shown are denoted by the same reference numerals. Similarly to the first embodiment, the engine casing according to the third embodiment includes a cylinder head 4 for gas, a cylinder 3 for the cylinder block 3, and a piston 5 provided to reciprocate in one end of the gas red body 3 (refer to the figure). 1); and the portions form the combustion chamber 10. The cylinder head 4 is provided with an intake valve 8 that opens and closes the intake port 8a, an exhaust valve 9 that opens and closes the exhaust port 9a, and a valve device that drives the intake valve 8 and the exhaust valve 9. The engine further includes: an exhaust device 5; and a secondary air supply device 70 that supplies air to the exhaust passage 7 of the exhaust device 50. The exhaust device 50 includes an i-th exhaust connected to the gas red cover 4. a tube 51; a second exhaust pipe 52 connected to the first exhaust pipe 51; and a third exhaust pipe 53 connected to the second exhaust pipe I54997.doc • 31 · 201239190 52, the exhaust pipes 51 '52, 53 form an exhaust passage 7. The first catalyst 21 and the second catalyst 22 are disposed at intervals in the exhaust passage 7. A branch pipe 3 is provided in an upstream portion of the first exhaust pipe 51. A tapered-divergent nozzle 4 is provided between the branch pipe 30 and the first catalyst 21. In the third embodiment, the branch pipe 30 also serves as the first secondary air supply pipe 76 that forms the first passage 71. In other words, the dedicated first passage 71 is discarded, and the branch portion 31 also serves as the first passage 71. It can also be said that the first passage 71 also serves as the branch portion 31. Further, the second secondary air supply pipe 77 is connected to the branch pipe 30 which also serves as the second secondary air supply officer 76, and is formed from the branching portion 31 (i-th passage 7A) to the second and second catalysts 21 and 22. The second passage 72 of the exhaust passage 7 between. The configuration other than this is the same as that of the first embodiment. Therefore, the detailed description of the third embodiment can be replaced by the drawings 9 to 9 and the detailed description thereof in the first embodiment. In the third embodiment, the reed valve 74 is coupled to the end portion of the branch pipe 3 opposite to the exhaust passage 7, and the air amount control valve and the air cleaner 78 are coupled to the upstream side. The reed valve 74 constitutes the reflecting portion 31b of the branch portion 31. That is, the shock wave from the exhaust passage 7 is branched toward the branch portion (on the first passage 7), and is reflected by the reed valve 74 (reflecting portion 31b) in the closed state, and then passes through the branch portion 3 (the second passage 71) again. Return to the exhaust passage 7. The shock wave collides with the exhaust gas traveling in the exhaust passage 7 to increase the pressure of the exhaust gas. When the exhaust valve 9 is opened, the reed valve 74 is closed, and the shock wave can be reflected by the reed valve 74. When the negative pressure is generated in the exhaust passage 7 by the action of the tapered_swelling nozzle 4, the reed valve 74 is opened, so that one of the outer ones and the human air can be supplied to the first passage 71. Thereafter, when a positive pressure is generated in the exhaust passage 7 by the exhaust pulsation, the secondary air introduced into the second passage 7 is supplied to the first and second via the second passage 154997.doc •32-201239190 72. The exhaust passage 7 between the catalysts 21, 22. Therefore, in the present embodiment, a sufficient amount of air can be supplied to the exhaust passage 7 downstream of the second catalyst 21. Further, according to the present embodiment, there is no need for a passage that functions exclusively as the branch portion 31 or a passage that functions exclusively as the first passage 71. Therefore, the use of the dedicated branch portion 31 and the dedicated third passage 7丨(Fourth Embodiment) The present invention is a cross-sectional view showing the configuration of an exhaust device and the like of the engine according to the fourth embodiment of the present invention. In the same manner as in the third embodiment, the engine 1 of the fourth embodiment includes the cylinder block 3 and is disposed in the cylinder block 3. a cylinder head 4 at the end; and a piston 5 (refer to the figure) that reciprocates in the cylinder block 3; and the portions form a combustion chamber 10°. The crimson cover 4 is provided with an air inlet for opening and closing the air inlet 8a. An exhaust valve 9 that opens and closes the exhaust port 9a; and a valve device for driving the intake valve 8 and the exhaust valve 9. The engine 1 further includes: an exhaust device 5; and an exhaust device 50 The exhaust passage 7 supplies air to the secondary air supply 70. 5 〇 括 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 The tube, the first block SB, and the KS 53, and the exhaust pipes 51, 52, and 53 form the exhaust gas passage, and the first catalyst 21 and the second catalyst are disposed at intervals along the drain passage 7 The branch pipe 3 is provided in the upstream portion of the exhaust pipe 51. 154997.doc • 33· 201239190 The branch pipe 30 also serves as the first secondary air supply pipe 76 forming the first passage 71. The second secondary air supply pipe 77 is connected to The branch pipe 30 of the first secondary air supply pipe 76 is also formed, and the second passage 72 of the exhaust passage 7 from the branch portion 31 (first passage 71) to between the first and second catalysts 21 and 22 is formed. In the fourth embodiment, the branch pipe 30 is used as one of the tapered and divergent nozzles. The other configuration is the same as that of the third embodiment (see Fig. 11). Therefore, the detailed description of the fourth embodiment can be made by the first embodiment. 1 to 9 and FIG. 11 of the third embodiment and the detailed descriptions thereof are used instead. In the first to third embodiments, the tapered portion 41, the throat portion 42, and the diverging portion 43 are formed in the branch portion 31. for The inventor of the present invention continues to carry out the results of active research and conceives a structure that is simpler in construction and can obtain the same effect. In the present embodiment, in order to generate the traveling shock wave 35b as a new shock wave, the inventor is provided. The branching portion 31 which is reflected by the shock wave 35 generated at the beginning of the exhaust stroke and propagates again to the exhaust passage 7. When the branch portion is viewed from a different viewpoint, the flow passage sectional area of the exhaust passage 7 at the position of the branch portion 31 is increased. Further, the cross-sectional area of the downstream flow path becomes smaller at this position. In other words, the tapered portion 4 and the throat portion 42 are formed by the branch portion 31. ” ” 砰 砰 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰 砰The population 31 & more upstream of the exhaust passage 7 part of the gas 5, and the subsection # + knife flow path sectional area, the knife branch P 31 flow path sectional area A4 added to the production, greater than the light Into the σ 2s * . Force &lt; · intersection 丨 J face in the downstream of the inlet channel downstream of the exhaust channel 7 part of the flow 154997.doc -34 · 201239190 road sectional area A7. A4+A5&gt;A7. Therefore, it is considered that the tapered portion 41 and the throat portion 42 are formed downstream of the inlet 3i & Thus, the diverging portion 43 can be formed only in the downstream of the inlet 31 & the tapered progressively expanding nozzle 4 〇〇 8 6 represents the cross-sectional area of the flow path of the diverging portion 43, and Α 7 &lt; Α 6β inlet 31 &amp; The portion between the expanded portions u becomes the throat portion 42. Thus, the throat 42 can also extend longer along the flow path direction. The tapered portion 4 and the diverging portion 43 need not have a configuration in which the cross-sectional area of the flow path is changed smoothly (continuously) toward the downstream, and the flow path can be formed in a stepwise manner. Composition. The configuration of the fourth embodiment can also be applied to the configurations of the above-described second and second embodiments. In this case, the diverging portion 43 is provided downstream of the connecting portion 71b of the first passage 71, whereby the tapered-swelling nozzle clasp can be substantially formed. In the case of this configuration, not only the branch portion 3 but also the third channel

The branch portion produces a change in the cross-sectional area of the flow path. Therefore, it is also possible to form the tapered portion 41 and the throat portion 42 in consideration of the exhaust passage 7 downstream of the first passage I-joining portion 71b. In this case, the portion of the exhaust passage 7 between the connecting portion 71b and the diverging portion 43 is the throat portion 42 » &lt;Fifth Embodiment&gt; FIG. 13 is an engine for explaining the fifth embodiment of the present invention. A cross-sectional view of the structure of the exhaust device or the like. In the drawings, the same reference numerals will be given to the portions corresponding to the respective portions shown in the above (4), and the description thereof will be omitted. The embodiment is applied to the exhaust passage 7 under the tapered _ diverging nozzle 4 游. The catalyst 23 is disposed. The downstream end 72b of the second passage 72 is coupled to the side of the catalyst 23. In other words, a cylindrical air introduction space 8 is formed in the downstream end 72b of the second passage 72 so as to open substantially the entire side surface of the catalyst. On the other hand, I54997.doc -35-201239190 is formed on the side surface of the catalyst 23, and a plurality of air introduction holes 82 are introduced into the air, and the secondary air supplied from the first passage 71 to the second passage 72 is introduced from the air. The space 81 enters the inside of the catalyst 23. The secondary air that has entered the inside of the catalyst 23 is mixed with the exhaust gas introduced from the upstream end 23a of the catalyst 23, and flows to the downstream end of the catalyst 23. Thus, in the inside of the catalyst 23, the tapered region 24A which is tapered toward the downstream from the upstream end 23a of the catalyst 23 becomes a low oxygen concentration region which is dominated by the exhaust gas from the combustion chamber 10. Further, the remaining region 24B other than the region 24 is a region of high oxygen concentration in which secondary air is sufficiently supplied. The catalyst 23 functions as a reduction catalyst in the low oxygen concentration region 24A, and functions as an oxidation catalyst in the high oxygen concentration region 24B. Therefore, one type of catalyst 23 can also serve as a reduction catalyst and an oxidation catalyst, so that the exhaust gas from the combustion chamber 10 can be sufficiently poisoned. Therefore, the purification efficiency of waste can be improved. Further, since one type of catalyst 23 is sufficient, the heat capacity of the entire exhaust unit 50 can be reduced. Thereby, when the engine is started, the catalyst 23 can be quickly activated, so that the exhaust gas can be sufficiently purified immediately after the engine is started. According to still another aspect of the present invention, in the range from the connection portion of the first passage 71 and the second passage 72 to the downstream end 7ib of the second passage 72, (the orifice) 83 is provided. The exhaust gas from the combustion chamber i is prevented from entering the first passage 71 without affecting the supply of the secondary air. Thus, the oxygen concentration of the line supplied to the second passage 72 can be increased. For example, in the other embodiments described above or described later, the same orifices may be provided with 154997.doc -36·201239190. FIG. 14 is a schematic perspective view for explaining a configuration example of the catalyst 23. The catalyst 23 has a bee-shaped metal carrier 85. The metal carrier 85 is formed by alternately laminating a flat plate (cavity) 86 having an opening and a corrugated foil (foil) 87 having an opening to form a honeycomb structure. In other words, the strip-shaped flat foil 86 is overlapped with the strip-shaped leather sheet 87 and wound into a roll shape. Thus, a metal carrier 85 having a cylindrical honeycomb structure is formed. The flat foil 86 is a plurality of air holes 86a. Equally dispersed and formed on a flat metal foil. The foil 87 is formed by, for example, uniformly dispersing a plurality of air holes 87a in a metal crucible formed in a stripe shape. A flat foil 86 is disposed on the outermost peripheral surface of the catalyst 23, and air is exposed on the outermost peripheral surface. The hole 86a corresponds to the air introduction hole 82. Fig. 15 is a cross-sectional view showing the configuration of an exhaust device and the like of the engine according to the sixth embodiment of the present invention. The portions corresponding to those in the above-mentioned 圊13 are denoted by the same reference numerals, and the description thereof will be omitted. In this embodiment, the downstream end 72b of the second passage 72 is connected to the side of the catalyst 23 and the upstream end 23a of the catalyst 23. In the outer peripheral region, a cylindrical air introduction space 88 in which the substantially entire side surface of the catalyst 23 is opened and the outer peripheral end 23a of the catalyst 23 is opened is formed in the downstream end 72b of the second passage 72. The catalyst 23 is formed. The secondary air supplied from the first passage 71 to the second passage 72 is supplied from the air introduction space 88 to the inside of the catalyst 23, for example, the side of the catalyst 23 and the upstream end of the catalyst 23. The outer peripheral area of 23a enters into the interior of the catalyst 23. The secondary air to the inside of the catalyst 23 is mixed with the exhaust gas introduced from the central portion of the upstream end 23a of the catalyst 23, and flows to the downstream end of the catalyst 23. Thus, 154997.doc •37-201239190 In the inside of the portion 23, the region 24A in which the central portion of the upstream end 23a of the catalyst 23 is tapered toward the downstream becomes a low oxygen concentration region in which the exhaust gas from the combustion chamber 1 is dominant. The remaining region 24B is a region of high oxygen concentration in which secondary air is sufficiently supplied. The catalyst 23 functions as a reduction catalyst in the low oxygen concentration region 24A and functions as an oxidation catalyst in the high oxygen concentration region 24B. Therefore, one catalyst 23 can be used as both a reduction catalyst and an oxidation catalyst. Since the secondary air is introduced from the outer peripheral region of the upstream end 23a of the catalyst 23, the "low oxygen concentration region 24 becomes smaller" than in the case of the fifth embodiment, that is, the oxygen is compared with the case of the fifth embodiment. The concentration region 25 becomes larger. Therefore, a sufficient amount of secondary air can be supplied to the catalyst 2, so that the exhaust gas from the combustion chamber 1 can be sufficiently detoxified. &lt;Fourth Embodiment&gt; Fig. 16 is a schematic view showing the configuration of an exhaust device of an engine according to a seventh embodiment of the present invention. In Fig. 16, the same reference numerals are attached to the corresponding portions of the respective portions shown in Fig. 1 described above. The fifth embodiment is an example in which an embodiment of the present invention is applied to a multi-cylinder engine. The engine 1 of the seventh embodiment includes a plurality of cylinders #8, #Ββ, each cylinder #8, #B includes: a cylinder block 3 (refer to FIG. ;); a cylinder head 4 disposed at one end of the cylinder block; The piston 5 (refer to FIG. 1) of the reciprocating motion in the cylinder block 3 and the portions form the combustion chamber 1〇. The cylinder head 4 is provided with an intake valve 8 that opens and closes the intake port 8a (refer to FIG. 1) (refer to FIG. 1); an exhaust valve 9 that opens and closes the exhaust port %; and is used to drive the intake valve 8 (refer to the figure 丨) and the valve device of the exhaust valve 9. The engine 1 further comprises: an exhaust device 5; and a 154997.doc

S -38· 201239190 Exhaust passage 7 of exhaust device 50 Secondary air supply device 70 for supplying air 〇Exhaust device 50 includes: first exhaust pipe 51 connected to cylinder head 4; connected to the first exhaust gas The second exhaust pipe 52 of the pipe 51; and the third exhaust pipe 53 connected to the second exhaust pipe 52. The exhaust pipes 51, 52, and 53 form an exhaust passage 7 (7A '7B &gt; 7C). In the embodiment, the first exhaust pipe 51 is formed with exhaust ports 9a connected to the plurality of combustion chambers 10, respectively. Individual exhaust passages 7A, 7B. The individual exhaust passages 7A, 7B are collected in the collecting portion 25 and connected to the collecting exhaust passage 7C. A tapered_riverging nozzle 仂 is provided in the collective exhaust passage 7C. The first and second catalysts 21 and 22 are disposed at intervals along the collective exhaust gas passage (four) on the downstream side of the tapered-divergent nozzle 40. Further, the second secondary air supply pipe 76 forming the second passage 71 is connected to the collective exhaust passage 7C between the collecting portion 25 and the tapered_riverging nozzle 4A. The second secondary air supply pipe 77 that forms the second passage 72 is connected to the first secondary air supply pipe 76 at the upstream end. The downstream end of the second secondary air supply pipe 77 is connected between the first and second catalysts 21 and 22, that is, connected to the collective exhaust passage 7C downstream of the first catalyst 21. The other configuration is the same as that of the above embodiment. 17A to 17C are diagrams showing the operation of the engine according to the seventh embodiment. When the exhaust port 9a of the first cylinder #8 is opened, the exhaust passage 9a is closed, and the individual exhaust passages 7A of the additional cylinder #A are closed. The branch unit 31 functions. That is, when the exhaust port % of the gas (four) B is turned on, the exhaust gas is exhausted from the exhaust port %, and the shock wave 35 is generated, and the exhaust gas 36 and the shock wave 35 are propagated through the individual exhaust passages 7B (refer to Fig. 17A). The shock wave 35 branches at the collecting portion 25 and 154997.doc -39 - 201239190 enters the individual exhaust passage 7A of the other cylinder #8. The shock wave 35 of the branch propagates to the upstream side through the individual exhaust passage 7A (refer to Fig. 7B). And reflected in the cylinder #8's exhaust valve 9 (closed state). That is, the exhaust valve 9 in the closed state functions as the reflecting portion 31b. The reflected shock wave 35 propagates to the downstream side through the individual exhaust passages 7 A, and reaches the collecting portion 25 again (see Fig. 7C) to collide with the exhaust gas 36. Thereby, the pressure at the entrance of the tapered-divergent nozzle 4 is raised to generate a new shock wave in the dilating portion 43. The external secondary air is introduced into the first passage 71 by the negative pressure generated by the generation of the new shock wave. Then, when the exhaust gas pulsation is followed by the exhausting passage 7 which is further upstream than the diverging portion 43 (when the positive pressure is applied, the secondary air introduced into the first passage 71 is sent to The second passage 72. Thereby, the secondary air is sent to the collective exhaust passage 7C downstream of the second catalyst 2丨. Thus, the individual exhaust passages 7A, 7B of the cylinders for closing the exhaust port 9a serve as points. The branch portion 3 1 can be realized by the same operation as that described with reference to the above-described Figs. 4A to 4C. The lengths of the individual exhaust passages 7a, 7B of the respective cylinders are such that the shock wave 35 and the exhaust gas 36 are reflected. The design is performed in such a manner that the collecting portion 25 collides. The cylinders #A and #B of the exhaust gas collection are in a closed state when the exhaust port 9a of one of the cylinders is in an open state, and the exhaust port % of the other cylinder is in a closed state. One of the relationships is for the cylinder group. More specifically, in the four-cylinder engine with cylinders #1, #2, #3, #4, the ignition sequence is set to cylinder #1_cylinder#3_cylinder#4-cylinder# 2. In this case, the group of cylinder #1 and cylinder #4 whose ignition timing differs by 36 相当于 is equivalent to the above two cylinders #A, #b Also, similarly, 154997.doc -40- 201239190 The group of cylinder #2 and cylinder #3 whose ignition timing differs by 360 degrees corresponds to the group of the above two cylinders #A, #B. That is, in the 4-cylinder engine, There are two pairs of cylinder pairs of the two cylinders #A and #B. <Other Embodiments> Fig. 18 is a perspective view showing an example of a ship on which an engine according to an embodiment of the present invention is mounted. 1 〇〇 includes a hull 102 and an outboard motor 1 〇1 having an engine 1 according to an embodiment of the present invention. In this example, two outboard motors 101 are mounted on the hull 102. The outboard machine ιοί includes, for example: An engine 1; a propeller (not shown) as a propulsion generating member; and a transmitting mechanism (not shown) for transmitting the driving force of the engine 1 to the propeller. The transmitting mechanism includes, for example, a rotating force by the driving force of the engine 1. a drive shaft; a propeller shaft coupled to the propeller; and a clutch disposed between the drive shaft and the propeller shaft. As a propulsion generating unit equipped with the ship 100, an inboard machine may be exemplified in addition to the outboard motor 1〇1 , inside and outside the machine. In addition, you can also use the example A jet pump unit that is placed in a water flow path by an impeller that is rotated by an engine is used as a propulsive force generating unit for the ship 100. Fig. 19 is a perspective view showing a vehicle in which an engine according to an embodiment of the present invention is not mounted. 'The electric two-wheeled vehicle as an example of the vehicle includes the body 201; the front wheel 2〇2 and the rear wheel 2〇3 (wheel) attached to the straight body, the single body 201, and the engine engine 丄 of the embodiment of the present invention The vehicle body is centered. The driving force generated by the engine 1 is transmitted to the rear wheel 203 by the transmission mechanism 2〇4. Further, the engine of the present invention can also be applied as an engine of a generator or a key chain. Of course, there is no limitation on the application of the present invention. 154997.doc 201239190 Fig. 20 is a cross-sectional view showing an exhaust passage or the like according to a modification of the embodiment. The first embodiment t' is as shown again in Fig. 2G, the first! The secondary air supply pipe 76', i.e., the mit 71, is connected downstream of the branch portion 31 to the exhaust gas passage 7. However, the connection position of the second channel 71 may be further upstream than the branch portion 3 (refer to reference numeral 71A) or may be the same position as the branch portion 31 (reference numeral 71Βρ μ, in the above embodiment, the relative position is indicated. An engine with one exhaust gas π is provided in one combustion chamber, but a plurality of exhaust gases σ may be provided with respect to one combustion chamber. Further, there is no upper chamber with respect to i combustion chambers. The example of the contraction-swelling nozzle is 'but it is also possible to provide two = upper nozzles with respect to one combustion chamber. These deformations can of course also be applied to a multi-cylinder engine having a plurality of combustion chambers. Further, the present invention can be applied to Further, in the above embodiment, the configuration is such that one branch portion is provided for each of the exhaust passages 2, but a plurality of branch portions may be slanted with respect to one exhaust passage. For example, in the configuration of the third embodiment (see FIG. 1), when the first channel 71 satisfies the condition of the branch portion 31 (see FIG. 5), the configuration has substantially a plurality of branch portions. Can also be set to self-exhaust The ends of the plurality of branch portions of the same position of the track 7 are connected to each other to have a branch portion of the annular passage. In this case, the shock waves propagating from the respective branch portions collide with each other and are reflected. In this case, The portion where the branch portions are connected (the portion where the shock waves collide with each other) serves as a reflecting portion. The reflecting portion is formed even if there is no member such as a wall. In the above embodiment, the first and second catalysts 21 and 22 are included. The second catalyst can be omitted as in the modification of the first embodiment shown in Fig. 21. 154997.doc • 42· 201239190 In this case, the downstream of the first catalyst 21 is supplied by the south flute! In the case where the other side of the first catalyst 21 is used as a reduction catalyst, the downstream side portion can function as an oxidation catalyst. That is, the exhaust gas pulsates and the second channel is misplaced. When the air is introduced into the sputum 21, the ratio of the air in the exhaust gas is rich. Thus, the downstream side portion of the first catalyst 21 functions as an oxidation catalyst. Therefore, the exhaust gas can be efficiently purified by the secondary air. 2nd to 4th and 6th The same deformation can be performed in the form. In the above embodiment, the air oxygen amount control valve 75 and the air cleaner are provided upstream of the reed valve 74 of the i-th channel 71, but the above may be omitted. In the above-described embodiment, 'the configuration of the reed valve 74 is disposed at the upstream end of the second channel '', but the reed valve 74 may be disposed at the upstream and downstream of the i-th channel 71. In this case, the upstream end 72a of the second passage 72 may be disposed between the reed valve 74 and the exhaust passage 7 in the first passage 71. Further, the catalyst shown in Fig. 14 may also be used. The first and/or second catalysts 21 and 22 in the embodiment other than the fifth and sixth embodiments. However, the first and/or second catalysts 21 and 22 do not need to have the air introduction port on the side surface. The medium carrier may be configured to be capable of introducing exhaust gas from the upstream end. Further, in the above-described embodiment, 'the configuration of supplying the secondary air to the exhaust passage via the second passage 72' has been described, but the supply destination of the secondary air may be a portion other than the exhaust passage. For example, in one embodiment shown in Fig. 22, the downstream end of the second passage 72 is coupled to the inlet 65 of the accumulator tank 63. 154997.doc • 43- 201239190 The pressure box 63 divides the high pressure at which the air pressure is higher than the atmospheric pressure. The air storage space 64° pressure storage tank 63 includes an inlet port 65 for introducing air, a check valve 66 for opening and closing the inlet port 65, and a discharge port 67 for discharging high-pressure air in the storage space 64. The check valve 66 is configured to open when the air pressure in the second passage 72 is higher than the air pressure in the storage space 64, and to allow air to flow from the second passage 72 to the accommodation space 64 » the check valve 66 as follows In a configuration, when the air pressure in the storage space 64 is equal to or higher than the air pressure in the second passage 72, the air is kept in a closed state. This prevents air from flowing out of the storage space 64 to the second passage 72. According to this configuration, the air is stored. The air in the space 64 is pressurized (compressed) so that pressure can be accumulated. That is, the energy of the exhaust gas can be converted into pressure energy and accumulated. The upstream end of the high pressure air supply path 68 is connected to the discharge port 66. An output control valve 69 is disposed in the middle of the high-pressure air supply path 68. The output of the high-pressure air (compressed air) accumulated in the accumulator tank 64 can be controlled by opening and closing the output control valve 69. The downstream end of the high pressure air supply path 68 is connected to a device 210 that operates with high pressure air. As an example of the device 210, it is an operation assisting device represented by a brake booster and a clutch booster. Further, as another example of the device 210, an air suspension device and a siren device can be cited. The embodiments of the present invention have been described in detail, but these are merely specific examples for clarifying the technical contents of the present invention. The present invention is not limited to the specific examples, and the scope of the present invention is only The scope of the patent application is limited. 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 Fig. 2 is a schematic view showing the configuration of a tapered-semi-expansion nozzle. Fig. 3 is a graph showing the relationship between the pressure ratio of the tapered-swelling nozzle and the Mach number. Fig. 4 is a cross-sectional view for explaining a traveling state of a shock wave and an exhaust gas. Fig. 4A shows the initial state of the exhaust stroke, Fig. 4B shows the state when the shock wave propagates in the branch path, and Fig. 4C shows the state when the shock wave reflected by the branch path collides with the exhaust gas. Fig. 5 is a schematic view showing an exhaust passage of a traveling path of a shock wave and a traveling path of an exhaust gas. Fig. 6 is a schematic view showing a pattern of photographs obtained by photographing the inside of a tapered and divergent nozzle by a schlieren method. Fig. 7 is a graph showing the relationship between the exhaust gas flow rate and the exhaust gas pressure at the time of shock wave acceleration. Fig. 8 is a graph showing the relationship between the flow rate of the exhaust gas at the time of shock wave acceleration and the temperature of the exhaust gas. Fig. 9 is a view for explaining the action of the secondary air supply device. Fig. 9A is a view showing an example of the relationship between the crank angle and the pressure in the exhaust passage. Fig. 9B is a view showing an example of the relationship between the crank angle and the mass flow rate of the gas in the third channel. Fig. 9C is a view showing an example of the relationship between the crank angle and the oxygen concentration in each portion of the exhaust passage and the secondary air supply means. Fig. 10 is a cross-sectional view showing the configuration of an exhaust passage or the like of an engine according to a second embodiment of the present invention. Fig. 11 is a cross-sectional view showing the structure of an exhaust passage of an engine according to a third embodiment of the present invention, 154997.doc-45·201239190. Fig. 12 is a cross-sectional view showing the configuration of the third embodiment of the present invention. 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 Fig. 14 is a schematic perspective view for explaining a configuration example of a catalyst. A cross-sectional view showing the configuration of an exhaust device 第 according to a sixth embodiment of the present invention. Fig. 16 is a schematic view showing the configuration of an exhaust device of an engine according to a seventh embodiment of the present invention. Fig. 10 is a schematic view showing the operation of the engine of the seventh embodiment. Figure Μ shows the initial state of the exhaust stroke. Figure 17B shows the state of the shock wave propagating in the individual exhaust passages (branch paths) of other cylinders. Figure I% shows the state of the shock wave reflected by the branch road and the exhaust gas. . Fig. 18 is a view showing a ship including an outboard motor equipped with an engine. Fig. 19 is a view showing a circle of an electric two-wheeled vehicle equipped with an engine. Fig. 20 is a cross-sectional view showing an exhaust passage or the like of a modification. Fig. 21 is a cross-sectional view showing the configuration of a modification of the first embodiment. Fig. 22 is a schematic view showing the configuration of an eighth embodiment of the present invention. [Main component symbol description] 1 Engine 2 Injector 3 Cylinder block 4 Cylinder head I54997.doc .46-

201239190 5 6 6a 7, 7C, 7B, 7C 7a 8 8a 9 9a 9ac 10 11 12 15 16 17 19

20 21 22 23 23a 24A 24B Piston Intake Channel Intake Channel Downstream Exhaust Channel Exhaust Channel Upstream Intake Valve Inlet Exhaust Valve Exhaust Port Vent Center Combustion Chamber Throttle Valve Bolt Link Crankshaft crankcase oxygen concentration sensor ECU First catalyst second catalyst contact catalyst upstream end low oxygen concentration region to oxygen concentration region • 47· 154997.doc 201239190 25 assembly portion 30 branch pipe 31 branch portion 31a Entrance 31b Reflection portion 35 Shock wave 35b New shock wave (traveling shock wave) 35c Expansion wave 36 Exhaust gas 40 Tapered-swelling nozzle 41 Tapering portion 42 Throat portion 43 Scaling portion 50 Exhaust device 51 First exhaust pipe 52 Row 2 Air pipe 53 Third exhaust pipe 55 Exhaust chamber 61 Flow path 62 Flow path 63 Accumulator tank 64 Storage space 65 Guide port 66 Check valve 154997.doc ·48· 201239190 67 Discharge port 68 High-pressure air supply path 69 Output control Valve 70 Secondary air supply device 71 First passages 71A, 71B, 91, reference numerals 92, 93, 94, 95, 99 71a Connection portion 72 of the upstream end 71b of the first passage and the exhaust passage 72 Connection portion 74 of the second passage 72a and the first passage and the connection portion of the exhaust passage 74 Reed valve 75 Air amount control valve 76 First secondary air supply pipe 77 Second secondary air supply pipe 78 Air cleaner 80 (2nd) Reed valve 81 Cylindrical air introduction space 82 Air introduction hole 83 Hole 85 Metal carrier 86 Flat foil, downstream end upstream end, downstream end 154997.doc • 49- 201239190 86a, 87a Air hole 87 Waveform Foil 88 Air introduction space 96a ' 96b ' 96c ' Curve 96d 100 Ship 101 Outboard motor 102 Hull 200 Electric two-wheeler 201 Body 202 Front wheel 203 Rear wheel 204 Transmission mechanism 210 Using high-pressure air to actuate A, B Gas red A1 The cross-sectional area of the flow path at the upstream end of the tapered portion A2 The cross-sectional area of the flow path of the throat A3 The cross-sectional area of the flow path at the downstream end of the diverging portion A4 The cross-sectional area of the flow path of the branch portion A5 The exhaust gas upstream of the branch inlet The cross-sectional area of the flow path of the part of the passage A6 The cross-sectional area of the flow path of the gradually expanding part A7 The cross-sectional area of the part of the exhaust passage which is further downstream than the inlet I54997.doc -5〇· 201239190

P PO Le Ls Ld a, b, c, XY The pressure taper of the taper is the distance from the center of the exhaust port to the center line of the flow path of the branch inlet (flow path length) Distance between the center line of the flow path section and the reflecting portion (flow path length) Distance from the center line of the flow path section of the branch inlet to the upstream end of the diverging portion (flow path length) Measurement of the flow path section of the branch branch inlet Center line of the center line exhaust passage 154997.doc •51 ·

Claims (1)

201239190 VII. Patent application scope: L An engine comprising: a combustion chamber formed with an exhaust port; an exhaust valve opening and closing the exhaust port; and an exhaust device having a guide from the combustion chamber through An exhaust passage of the exhaust gas discharged from the exhaust port; and an air supply device that supplies air; the exhaust device includes: a taper. The crucible is disposed in the exhaust passage, and the cross-sectional area of the flow path at the downstream end is smaller than the cross-sectional area of the flow path at the upstream end; the diverging portion is disposed downstream of the tapered portion in the exhaust passage and a cross-sectional area of the flow path at the downstream end is larger than a cross-sectional area of the flow path at the upstream end; and a branch portion that is at a higher speed than the exhaust gas flowing from the combustion chamber to the exhaust passage when the exhaust port is opened a shock wave propagating downstream in the passage branches from the exhaust passage further upstream than the diverging portion, and the shock wave is again transmitted to the exhaust passage; the air supply device includes: a first passage having a a flow from the upstream end toward the downstream end through the first flap valve 'and a downstream end connected to the exhaust passage further upstream than the diverging portion; and a second passage having an upstream end connected to the first passage The exhaust device is further downstream than the first reed valve; and 154997.doc 201239190 is configured to: exhaust the exhaust gas flowing from the combustion chamber to the exhaust passage through the above-mentioned a contraction portion that collides with a shock wave propagating in the branch portion between the branch portion and the diverging enthalpy, thereby increasing the force of the exhaust gas at the tapered portion, and by which the pressure is improved The exhaust gas is generated by the diverging portion to generate a new shock wave; and the air supply device is configured to generate the exhaust passage in the exhaust passage further upstream than the diverging portion by the newly generated shock wave. The negative pressure is introduced into the first passage ′ through the first reed valve, and the introduced air is supplied to the second passage by a positive pressure generated in the exhaust passage upstream of the purely expanding portion. . For example, the engine of the item 1 of the month 1 is such that the energy loss of the gas flowing through the flow path from the upstream end to the downstream end of the first passage is smaller than the flow from the downstream end of the I, to the first passage. The manner in which the amount of gas in the flow path at the downstream end is lost constitutes the first passage and the second passage. The engine of the long item 1, wherein the first channel and the second channel are configured to block the second channel to allow air to flow from the upstream end to the downstream end of the first channel The flow at the downstream end is larger than the field, so that the first passage is closed at the upstream side of the portion connected to the second passage, and the air flows from the downstream of the second passage to the downstream end of the first passage. The flow coefficient of the downstream end of the first passage at the time. The engine of item 1, wherein the air supply device further includes a second '4' disposed in the second passage' and passing air from the upstream end of the second passage toward the downstream end. I54997.doc 201239190 5. The engine of the request item! support.卩 Also as the above! The engine of claim 1, further comprising an orifice, wherein the connecting portion connected to the second passage and the first passage are disposed between the first passage and the first passage. The downstream end 7. The bowing engine of the present invention, wherein the first exhaust passage is connected to the engine of the upper end 7 of the engine, wherein the first catalyst is disposed in the first air passage. Further downstream of the diverging portion, 'the downstream end of the second passage in the row is connected to the downstream of the upper first catalyst. The passage of the passage is higher than the above 9», wherein the exhaust medium meets Including the second touch is disposed in the gas channel below the second channel. The row on the downstream side is the engine of the item 7, which further includes the clock in the i-th gas channel. The downstream end of the second passage is located further downstream than the diverging portion, and the downstream end of the second passage is in the first exhaust passage. The side of the medium is connected to the upper 11 · the engine of claim 1 Wherein the third inlet hole is introduced, and the air having the downstream end of the air is connected to the air The engine of claim 10, wherein the exhaust passage of the second passage is such that an upstream end of the first catalyst from the second passage is introduced into the third catalyst. In the engine, the second passage &lt; downstream end is connected to the exhaust passage of 154997.doc 201239190 such that air from the second passage can be introduced into the second catalyst from the upstream end of the first catalyst. M. The request item (1) 丨 ' 'where the oxygen level in the second channel is higher than the oxygen concentration in the exhaust channel upstream of the first catalyst. 15. - a vehicle having the request The engine of any item in item ljli4. 16· A ship having an engine as claimed in any one of claims 1 to 14. 154997.doc