JP2018189005A - Lubrication device of engine and knapsack type blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently cool oil for engine lubrication.SOLUTION: A lubrication device 200 of an engine 6 includes: a box-shape oil case 80 which can store oil; a partition wall 84 which partitions the interior of the oil case 80 into a first chamber 91 and a second chamber 92; a first communication path (communication path 59) which communicates a crank chamber 24 and the first chamber 91; a second communication path (oil supply passage 54 and a suction pipe 55) which communicates the crank chamber 24 and the second chamber 92; and a tubular body 110 which is arranged on the outside of the oil case 80, is exposed and allows one end part 110a thereof to be communicated with the first chamber 91 and the other end part 110b thereof to be communicated with the second chamber 92. Upon a positive pressure in the crank chamber 24, oil in the crank chamber 24 is discharged into the first chamber 91 from the crank chamber 24 through the first communication path and, upon a negative pressure in the crank chamber 24, oil in the second chamber 92 is sucked via the second communication path and at least a part of oil in the first chamber 91 reaches the second chamber 92 through the tubular body 110.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a lubrication device for an engine (internal combustion engine) and a backpack type blower working machine using the engine as a drive source.

  Patent document 1 is disclosing the backpack type blower as an example of the backpack type blower working machine which uses an engine as a drive source. In patent document 1, the fan for generating the ventilation of a backpack type blower is provided in the one end part of the crankshaft of an engine. In patent document 1, the flow path for utilizing a part of the wind generated by the fan as engine cooling air is formed by the engine cover (see paragraph 0020 of patent document 1).

Japanese Patent No. 4636551

  However, in the engine as described above, the oil for engine lubrication is cooled by applying cooling air to the outer surface of the engine, so that it is difficult to efficiently cool the oil.

  In view of such a situation, an object of the present invention is to efficiently cool oil.

  Therefore, according to the first aspect of the present invention, an engine lubrication device includes a box-shaped oil case capable of storing oil for engine lubrication, a partition wall that partitions the oil case into a first chamber and a second chamber, and a piston. Is exposed outside the oil case, the first communication passage communicating the crank chamber and the first chamber, the internal pressure of which fluctuates due to the reciprocating motion, the second communication passage communicating the crank chamber and the second chamber, and the oil case. And a tubular body having one end communicating with the first chamber and the other end communicating with the second chamber. When the crank chamber has a positive pressure, oil in the crank chamber is discharged from the crank chamber through the first communication path into the first chamber. At the time of negative pressure in the crank chamber, the oil in the second chamber is sucked through the second communication passage, and at least a part of the oil in the first chamber reaches the second chamber through the tubular body.

  In the second aspect of the present invention, the engine lubrication device includes a cooling air supply device that is driven by the engine and sends the cooling air toward the engine. Cooling air from the cooling air supply device hits the tubular body.

  In the third aspect of the present invention, the shoulder type blower working machine includes a blower fan that is rotationally driven by the engine having the engine lubrication device of the second aspect, and a part of the air sucked by the rotation of the blower fan. And a blow-out port that blows out the remaining portion of the air sucked by the rotation of the blower fan. The blower fan functions as the aforementioned cooling air supply device. Cooling air that has passed through the guide portion hits the tubular body.

  According to the present invention, the tubular body is disposed outside the oil case and exposed, and one end portion communicates with the first chamber and the other end portion communicates with the second chamber. Thereby, in the process where at least a part of the oil in the first chamber reaches the second chamber through the tubular body, the heat of the oil can be released to the outside through the tubular body, so that the oil can be efficiently cooled. .

The perspective view of the backpack type blower in one embodiment of the present invention Side view of the shoulder blower in the embodiment Sectional drawing of the backpack type blower in the one embodiment The top view of the oil case in the one embodiment The front view of the oil case in the one embodiment AA sectional view of FIG. The figure which shows schematic structure of the lubrication apparatus of the engine in the said one Embodiment.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 3 are a perspective view, a side view, and a cross-sectional view of a shoulder blower according to an embodiment of the present invention. In the present embodiment, a backpack type blower will be described as an example of the backpack type blower working machine according to the present invention, but the backpack type blower work machine according to the present invention is not limited to a backpack type blower. In the following description, for convenience of explanation, as shown in FIGS. 2 and 3 and FIGS.

  A backpack-type blower (engine blower) 1 is used for, for example, blowing work such as fallen leaves and cut grass. The shoulder type blower 1 has a blower unit 3 attached to a frame 2 for an operator to carry on the back, and a blower pipe (ventilation pipe) 5 for discharging air to an ejection duct (ventilation duct) 4 of the blower unit 3 is communicated. . The blower unit 3 ejects the air sucked by the rotation of the blower fan 7 driven by the engine 6. The base end portion of the blower pipe 5 is supported by the frame 2 and is connected to and communicated with the opening end portion of the ejection duct 4.

  The frame 2 is for the operator to carry the blower unit 3 on his / her back, and is composed of a backrest portion 2a extending vertically and hitting the operator's back, and a pedestal portion 2b extending rearward from the lower portion of the backrest portion 2a. It is L-shaped. A pair of shoulder straps 8-1 and 8-2 are attached to the backrest portion 2 a of the frame 2 for the operator to carry on his back.

  The blower fan 7 is accommodated in the volute case 9. An engine 6 that rotates the blower fan 7 is integrally assembled with the volute case 9.

  The blower unit 3 is mounted on the frame 2 via a vibration suppression mechanism. Coil springs 10-1 and 10-2 constituting a vibration suppressing mechanism are interposed between the lower portion of the blower unit 3 and the base portion 2 b of the frame 2. Coil springs 10-3 and 10-4 constituting a vibration suppressing mechanism are interposed between the front portion of the blower unit 3 and the backrest portion 2a.

  The volute case 9 is provided with an air suction port 9a at the front. A cylindrical air ejection duct 4 is integrally provided on the right side of the volute case 9. An enlarged diameter portion 4 a having a large diameter is provided at the tip of the cylindrical ejection duct 4. A base end portion of the blower pipe 5 supported by the frame 2 is inserted into the enlarged diameter portion 4a of the ejection duct 4 in a floating manner.

  The blower pipe 5 is for releasing air ejected from the blower unit 3 held by an operator. The blower pipe 5 is connected to the elbow part 5a floatingly connected to the ejection duct 4 of the blower unit 3, the flexible bellows pipe part 5b connected to the tip of the elbow part 5a, and the tip of the bellows pipe part 5b. The rotating pipe portion 5c is connected, the short pipe portion 5d is connected to the rotating pipe portion 5c, and the end nozzle portion (blowing port) 5e is connected to the short pipe portion 5d.

  A control handle 11 for holding the blower pipe 5 is attached in the vicinity of the connecting portion between the rotating pipe portion 5c and the bellows pipe portion 5b. The control handle 11 is provided with a trigger lever 12 for operating the blower unit 3.

  A fuel tank 13 for storing liquid fuel such as gasoline is mounted on the pedestal 2b at the lower part of the blower unit 3, and a fuel tank cap 14 is provided at the upper part of the fuel tank 13. The blower unit 3 is provided with a starter handle 15 for starting the engine 6. The fuel in the fuel tank 13 is supplied to a carburetor (not shown) via a fuel pipe (not shown), and the vaporized fuel is sent to the engine 6 together with air and sparked by a spark plug (not shown). It has become so. The exhaust after combustion is supplied to a muffler (not shown), muffled, and exhausted to the outside.

  The arm-type throttle lever 16 shown in FIG. 2 can move the arm up and down around the rotation shaft 16a, and can be freely expanded outward by the rotation shaft 16b. The rotary shaft 16b is provided with a spring, and urges it to return to the inside when the arm is expanded outward. This makes it possible to adjust the throttle at a position that matches the working posture. Further, the air cleaner cover 18 shown in FIG. 2 can be attached and detached with upper and lower knob screws.

  Here, the main usage procedure of the backpack type blower 1 will be described. The operator pulls the starter handle 15 to start the engine 6 of the blower unit 3, holds the frame 2 on the back, holds the control handle 11 with the right hand, and operates the throttle with the arm type throttle lever 16 with the left hand, Air is discharged from the end nozzle portion 5e of the blower pipe 5.

  By the way, in this embodiment, a part of the air sucked by the rotation of the blower fan 7 (a small portion of the air sucked by the rotation of the blower fan 7) is supplied to the jet duct 4 and / or the volute case 9. A guide portion (not shown) for guiding toward is formed. Here, as described above, the remaining portion of the air sucked by the rotation of the blower fan 7 (the majority of the air sucked by the rotation of the blower fan 7) is discharged from the end nozzle portion 5e of the blower tube 5. (Squirted). Therefore, the end nozzle portion 5e of the blower pipe 5 corresponds to the “blow-out port” of the present invention. The blower fan 7 functions as the “cooling air supply device” of the present invention, and sends the cooling air toward the engine 6. Further, the cooling air from the blower fan 7 strikes a tubular body 110 described later through the above-described guide portion.

  FIG. 3 shows the engine 6 when the piston 20 is located near the top dead center. The engine 6 is an OHV (Over Head Valve) type four-stroke engine and is air-cooled. The engine 6 includes a cylinder block 22 in which a cylinder 21 that accommodates a piston 20 in a reciprocable manner is formed, a crankcase 25 that is attached to a lower portion of the cylinder block 22 and forms a crank chamber 24 together with the cylinder block 22, and a cylinder block And a cylinder head 27 which is attached to an upper portion of the cylinder 22 and forms a combustion chamber 26 together with the cylinder block 22. The internal pressure of the crank chamber 24 fluctuates due to the reciprocating motion (vertical motion) of the piston 20.

  An oil case 80 is provided below the crankcase 25. The oil case 80 can store oil for lubricating the engine 6 (hereinafter simply referred to as “oil”). Here, the upper surface of the box-shaped oil case 80 having an upper surface opening is covered with the crankcase 25, whereby the oil tank 100 is formed. Of course, the oil tank 100 can also store oil.

  A crankshaft 30 as an output shaft is rotatably supported by a connecting portion between the cylinder block 22 and the crankcase 25 via a bearing. The crankshaft 30 is connected to the piston 20 via a connecting rod 29, whereby the reciprocating motion of the piston 20 is converted into the rotational motion of the crankshaft 30. Both ends of the crankshaft 30 protrude out of the crank chamber 24. A blower fan 7 is coaxially fixed to one end (front end) of the crankshaft 30. Therefore, the blower fan 7 can be rotationally driven by the engine 6 via the crankshaft 30.

  The cylinder head 27 is formed with an intake port (not shown) and an exhaust port 27a. The intake port (not shown) is opened and closed by an intake valve (not shown), and the exhaust port 27a is opened and closed by an exhaust valve 27b.

  4 and 5 are a plan view and a front view of the oil case 80, respectively. 6 is a cross-sectional view taken along line AA of FIG. In addition, illustration of the tubular body 110 is abbreviate | omitted in FIG.

  The oil case 80 has a box shape with an upper surface opening, and has a substantially rectangular shape in plan view. The oil case 80 has a box shape with an opening on the top surface and a body portion 81 that is substantially rectangular in plan view, and an outer flange portion 82 formed on the edge of the opening surface of the body portion 81.

  Through holes 83 are respectively formed at the four corners of the outer flange portion 82. A male screw portion of a bolt for fixing the oil case 80 to the crankcase 25 can be inserted into the through hole 83.

  A plurality of (9 in FIG. 5) heat radiation fins 95 are provided on the bottom 81a of the main body 81 so as to protrude downward. These fins 95 extend in the front-rear direction substantially in parallel to each other in the left-right direction.

  The oil case 80 (inside the main body 81) is partitioned into a first chamber 91 and a second chamber 92 by a partition wall 84. The partition wall 84 includes a pair of left and right side walls 84a and 84b and a rear wall 84c. The partition wall 84 is U-shaped in plan view. In the present embodiment, when the engine 6 is used for the longest time (upright state), when the specified amount of oil is stored in the oil case 80, the oil does not get over the partition wall 84. The height of the partition wall 84 is set to the extent.

  The second chamber 92 is formed by being surrounded by the inner surface of the partition wall 84, the inner surface of the front wall of the main body 81, and the upper surface of the bottom 81 a of the main body 81. A through hole 86 is formed in a portion of the front wall of the main body 81 that constitutes the second chamber 92. A cylindrical member 88 is inserted and fixed in the through hole 86.

  The first chamber 91 is formed by being surrounded by the outer surface of the partition wall 84, the inner surfaces of the front wall, the rear wall, the left side wall, and the right side wall of the main body 81, and the upper surface of the bottom 81a of the main body 81. ing. A through hole 87 is formed in a portion of the front wall of the main body 81 that constitutes the first chamber 91. A cylindrical member 89 is inserted and fixed in the through hole 87. The first chamber 91 is formed so as to surround the outside of the second chamber 92 in a U shape in plan view.

  In the present embodiment, the through hole 86 and the cylindrical member 88 are disposed slightly to the right of the central portion of the main body portion 81 in the left-right direction. On the other hand, the through hole 87 and the cylindrical member 89 are disposed in the vicinity of the left end portion of the main body 81.

  The tubular body 110 is disposed outside the oil case 80 and exposed. In the present embodiment, the tubular body 110 is made of a resin having flexibility. One end portion 110 a of the tubular body 110 is connected to the tubular member 89. Therefore, the one end portion 110 a of the tubular body 110 communicates with the first chamber 91 via the tubular member 89. The other end 110 b of the tubular body 110 is connected to the tubular member 88. Therefore, the other end 110 b of the tubular body 110 communicates with the second chamber 92 via the tubular member 88. Here, as shown in FIG. 3, the tubular body 110 is located between the blower fan 7 and the oil case 80.

  Returning to FIGS. 4 to 6, a recess 85 is formed in a portion of the upper surface of the bottom 81 a of the main body 81 that constitutes the second chamber 92. A suction port 55a (see FIG. 3 and FIG. 7 described later) of the suction pipe 55 is located immediately above the recess 85, and the recess 85 and the suction port 55a of the suction pipe 55 are opposed to each other. Here, in a state where the engine 6 is used for the longest (upright state), when a specified amount of oil is stored in the oil case 80, the suction port 55 a of the suction pipe 55 serves as the oil in the second chamber 92. The suction port 55a of the suction pipe 55 is disposed so as to be positioned below the surface. Further, the suction port 55 a of the suction pipe 55 is disposed in the vicinity of the recess 85 of the second chamber 92 in order to suck up oil from the vicinity of the bottom surface of the second chamber 92.

  An opening end 59b (see FIG. 7 described later) on the oil tank 100 side of the communication passage 59 described later is positioned above the portion constituting the first chamber 91 on the upper surface of the bottom 81a of the main body 81. . In the present embodiment, the opening end portion 59 b on the oil tank 100 side of the communication passage 59 is located immediately above the center portion in the plan view of the bottom portion 81 a of the main body portion 81. Here, in the state where the engine 6 is used for the longest (upright state), when the specified amount of oil is stored in the oil case 80, the opening end portion 59b on the oil tank 100 side of the communication passage 59 is An opening end portion 59b on the oil tank 100 side of the communication path 59 is disposed so as to be positioned above the oil surface of the first chamber 91. Further, the partition wall 84 allows the oil discharged into the oil tank 100 from the opening end portion 59 b on the oil tank 100 side of the communication path 59 to enter the first chamber 91 without directly entering the second chamber 92. Is installed in the main body 81.

  In the present embodiment, the distance L1 between the one end portion 110a of the tubular body 110 and the other end portion 110b of the tubular body 110 is such that the open end portion 59b of the communication passage 59 on the oil tank 100 side and the suction port 55a of the suction pipe 55. Longer than the distance L2. Here, the distance L1 between the one end portion 110a of the tubular body 110 and the other end portion 110b of the tubular body 110 corresponds to the distance between the through holes 86 and 87, and the cylindrical members 88 and 89. Corresponds to the distance between.

  In the present embodiment, the through hole 87 is positioned higher than the through hole 86. Therefore, the cylindrical member 89 is positioned higher than the cylindrical member 88. Accordingly, the one end 110 a of the tubular body 110 is positioned higher than the other end 110 b of the tubular body 110.

  FIG. 7 is a diagram showing a schematic configuration of the lubrication device 200 of the engine 6 in the present embodiment, and shows the lubrication device 200 when the piston 20 is located at the top dead center.

  The valve operating mechanism 70 for driving the intake valve and the exhaust valve 27b is driven by a valve drive gear 71 and a valve drive gear 71 that are coaxially fixed to the other end portion (rear end portion) of the crankshaft 30 and has a cam. It is comprised by components, such as the cam gear 72 and the rocker arm 73 (refer FIG. 3) which were connected. The valve drive chamber 52 is provided in the middle of a supply passage 51 that connects the valve train chamber 31 formed in the cylinder head 27 and the oil tank 100. Of the valve operating mechanism 70, the valve drive gear 71 and the cam gear 72 are accommodated in the valve drive chamber 52. Parts such as the rocker arm 73 are provided in the valve operating chamber 31 (see FIG. 3).

  An oil feed passage 54 is provided between the oil tank 100 and the cylinder block 22. A metal suction pipe 55 extending in the vertical direction is provided at the end of the oil feeding passage 54 on the oil tank 100 side. The lower opening end of the suction pipe 55 functions as a suction port 55a for sucking oil.

  The oil feed passage 54 and the suction pipe 55 communicate with the inside of the crank chamber 24 and the second chamber 92 through the oil from the second chamber 92 when the inside of the crank chamber 24 tends to become negative pressure due to the rise of the piston 20. The function of sucking up and supplying it to the crank chamber 24 is realized. Therefore, the oil feeding passage 54 and the suction pipe 55 communicate with the crank chamber 24 and the second chamber 92 of the oil tank 100 (oil case 80) corresponding to the “second communication passage” of the present invention. Further, the oil in the second chamber 92 is sucked through the oil feed passage 54 and the suction pipe 55 at the time of negative pressure in the crank chamber 24. Due to the suction of the oil, at least a part of the oil in the first chamber 91 reaches the second chamber 92 through the tubular body 110.

  An opening end portion 54 a that opens into the crank chamber 24 of the oil feeding passage 54 is provided on the side wall 24 b of the crank chamber 24. The position of the opening end 54a is provided at a position where the piston 20 opens as the piston 20 moves while the piston 20 moves from the position near the top dead center toward the top dead center, and has moved to a position near the top dead center. The lower skirt portion 20a of the piston 20 is located on the bottom dead center side. Accordingly, the opening end portion 54a of the oil feeding passage 54 is already fully opened when the piston 20 reaches the top dead center.

  A one-way valve 57 is provided in the middle of the oil feeding passage 54. The one-way valve 57 opens and closes according to the pressure change in the crank chamber 24. The one-way valve 57 is configured to open in a state where the pressure in the crank chamber 24 is low with respect to the oil tank 100 to connect the oil feed passage 54 and close in a state where the pressure in the crank chamber 24 is higher. Yes.

  A communication passage 59 is provided between the bottom of the crank chamber 24 and the oil tank 100. The communication passage 59 communicates between the crank chamber 24 and the first chamber 91 of the oil tank 100 (oil case 80) corresponding to the “first communication passage” of the present invention. The communication path 59 is for sending oil mist generated in the crank chamber 24 and oil liquefied by the oil mist to the oil tank 100. Here, the open end 59b of the communication passage 59 on the oil tank 100 side corresponds to the “discharge port of the first communication passage” of the present invention.

  A reed valve 60 is provided at an open end 59a of the communication passage 59 that opens to the crank chamber 24 side. The reed valve 60 is configured to be openable and closable in accordance with a change in the pressure in the crank chamber 24, and is configured to open when the inside of the crank chamber 24 becomes a positive pressure to bring the communication passage 59 into a communication state. Therefore, when the reed valve 60 is opened and the communication passage 59 is in a communication state, oil mist and oil in the crank chamber 24 are sent into the oil tank 100 through the communication passage 59. Therefore, the oil in the crank chamber 24 is discharged from the crank chamber 24 through the communication path 59 into the first chamber 91 at the time of positive pressure in the crank chamber 24.

  An opening end 51 a of the supply passage 51 is open in the oil tank 100. Here, in a state where the engine 6 is used for the longest time (upright state), when a specified amount of oil is stored in the oil case 80, the opening end portion 51 a of the supply passage 51 is formed in the first chamber 91. An opening end 51a of the supply passage 51 is disposed so as to be positioned above the oil surface.

  An opening end portion 51 b on the valve operating chamber 31 side of the supply passage 51 opens to the cylinder block 22 side of the valve operating chamber 31. Therefore, the oil mist flowing through the supply passage 51 lubricates the valve mechanism 70 in the valve drive chamber 52, is discharged from the open end 51 b and is supplied into the valve chamber 31, and the rocker arm in the valve chamber 31. Lubricate 73 etc.

  A plurality of suction pipes 46 are provided in the valve train chamber 31 to suck oil accumulated in the valve train chamber 31. The suction pipe 46 is connected to the connection passage 45. The connecting passage 45 is provided on the opposite side of the valve chamber 31 from the crank chamber 24. A direct passage 47 is provided in the connection passage 45. During negative pressure in the crank chamber 24, the valve train chamber 31 and the crank chamber 24 communicate with each other via the direct passage 47. An open end 47 a that opens into the crank chamber 24 of the direct passage 47 is provided on the side wall 24 b of the crank chamber 24. The position of the opening end 47a is opened as the piston 20 moves while the piston 20 moves from the position near the top dead center toward the top dead center, like the opening end 54a of the oil feeding passage 54. The lower skirt portion 20a of the lower part of the piston 20 which is provided at the position and has moved to the position near the top dead center is located on the bottom dead center side. Therefore, the open end 47a of the direct passage 47 is already fully opened when the piston 20 reaches the top dead center.

  The opening end 47a of the direct passage 47 is provided at a position where the opening end 54a on the crank chamber 24 side of the oil feeding passage 54 opens after opening. For this reason, since the open end portion 47a of the direct passage 47 is closed when the open end portion 54a of the oil feed passage 54 is fully opened, the negative pressure in the crank chamber 24 does not act on the direct passage 47. By acting on the oil passage 54, the oil can be sufficiently supplied to the crank chamber 24 first, and the opening end 47a is opened so that the air can also be sufficiently supplied.

  A one-way valve that allows an oil flow from the valve chamber 31 to the crank chamber 24 side and restricts an oil flow from the crank chamber 24 to the valve chamber 31 side on the open end 47a side of the direct passage 47. 48 is preferably provided. Thereby, it is possible to reliably prevent the oil and oil mist from flowing back from the crank chamber 24 to the valve operating chamber 31, and as a result, it is possible to more reliably suppress the oil accumulated in the valve operating chamber 31.

  One end portion of the breather passage 36 is opened at a substantially central portion of the valve operating chamber 31, and the other end portion of the breather passage 36 is connected to the air cleaner 63. The breather passage 36 is provided for the purpose of discharging blow-by gas to the combustion chamber 26 (see FIG. 3). The oil mist and blow-by gas in the valve operating chamber 31 are sent to the air cleaner 63 through the breather passage 36, and are separated into oil and blow-by gas by an oil separator 63a provided in the air cleaner 63. The breather passage 36 is provided with a one-way valve 36b. The one-way valve 36b can prevent the backflow of blow-by gas and oil mist from the air cleaner 63 to the valve operating chamber 31 side.

  The gas-liquid separated oil is sent to the crank chamber 24 through a circulation passage 65 that communicates the air cleaner 63 and the crank chamber 24. The circulating passage 65 is provided with a one-way valve 65a that allows only the flow to the crank chamber 24 side. On the other hand, the blow-by gas separated from the gas and liquid is sent to the combustion chamber 26 together with the intake air.

  A return passage 66 for returning the oil in the valve drive chamber 52 into the crank chamber 24 is provided between the bottom of the valve drive chamber 52 on the oil tank 100 side and the direct passage 47. When the crank chamber 24 has a negative pressure, the oil accumulated in the valve drive chamber 52 is sucked through the return passage 66.

  A flow rate adjusting passage 67 is provided between the valve drive chamber 52 and the oil feeding passage 54. Similar to the return passage 66, the flow rate adjustment passage 67 has a function of sucking oil and oil mist in the valve drive chamber 52. The flow rate adjusting passage 67 sucks the air in the valve drive chamber 52, so that the flow rate of oil supplied to the crank chamber 24 through the oil feeding passage 54 is adjusted. If the amount of sucked air is large, the flow rate of oil supplied through the oil feeding passage 54 decreases. The flow rate adjusting passage 67 is preferably separated from the bottom of the valve drive chamber 52 and provided at a position where it is difficult to suck the oil staying in the valve drive chamber 52.

  The connection position of the flow rate adjusting passage 67 to the oil feeding passage 54 is located closer to the oil tank 100 than the one-way valve 57 provided in the oil feeding passage 54. For this reason, when the oil supply is shut off by the one-way valve 57, the oil accumulates in the oil supply passage 54 on the oil tank 100 side of the one-way valve 57, and the oil flow passage 54 and the oil supply passage 54 are connected to each other. Becomes a state where oil has accumulated. For this reason, at the timing when the oil feeding passage 54 sucks air from the flow rate adjusting passage 67, only air does not flow through the oil feeding passage 54, and the oil in the oil feeding passage 54 together with the air sent from the valve drive chamber 52. It is sent to the crank chamber 24.

  In the present embodiment, the flow rate adjusting passage 67 is provided with a flow restrictor 68 that adjusts the flow rate of air sent from the valve driving chamber 52 to the oil feeding passage 54. The flow restrictor 68 has a communication passage formed with a cross-sectional area smaller than that of the flow rate adjusting passage 67.

  Here, as described above, the flow rate adjusting passage 67 serves to adjust the flow rate of oil supplied to the crank chamber 24 via the oil feeding passage 54 by sucking the air in the valve drive chamber 52. . The flow rate adjusting passage 67 of the present embodiment has a cross-sectional area that can send a sufficient amount of air to the oil feeding passage 54. Then, by attaching the flow restrictor 68 to the flow adjusting passage 67, the cross-sectional area of the flow adjusting passage 67 is reduced, and the amount of air to be sent to the oil feeding passage 54 is adjusted. By doing so, the amount of air sent to the oil feeding passage 54 can be adjusted more appropriately and easily without being affected by manufacturing tolerances of the flow rate adjusting passage 67.

  Accordingly, the circulation path of the lubrication apparatus 200 includes the suction pipe 55, the oil feeding path 54, the communication path 59, the supply path 51, the suction pipe 46, the connection path 45, the direct passage 47, the breather path 36, the circulation path 65, and the return path 66. And a flow rate adjusting passage 67.

  When the engine 6 is started, a pressure change occurs in the crank chamber 24 due to the up-and-down movement of the piston 20, the crank chamber 24 is depressurized when the piston 20 is raised, and tends to become negative pressure, and the crank chamber 24 is lowered when the piston 20 is lowered. The pressure is increased and the pressure tends to be positive.

  The crank chamber 24 tends to become negative pressure, and the opening end portion 54a of the oil feed passage 54 begins to open as the piston 20 moves toward the top dead center, and the crank chamber 24 and the second chamber 92 of the oil tank 100 communicate with each other. Then, the negative pressure in the crank chamber 24 acts on the oil feeding passage 54. Since the opening end portion 54a is in a state in which the opening end portion 47a of the direct passage 47 is still closed when the opening end portion 54a is fully opened, the negative pressure in the crank chamber 24 can be sufficiently applied to the oil feeding passage 54. . Therefore, the oil pumped from below the oil surface of the second chamber 92 can be efficiently supplied into the crank chamber 24.

  When the oil in the second chamber 92 is pumped up, the oil level in the second chamber 92 is lowered, so that at least a part of the oil in the first chamber 91 causes the tubular body 110 to move in response to the reduction in the oil level. Pass through to the second chamber 92. About the oil in the middle from the 1st chamber 91 to the 2nd chamber 92, heat is taken away (that is, it cools) in the tubular body 110 which the cooling air from the ventilation fan 7 hits. In addition, the oil in the first chamber 91 can be agitated by flowing the oil in the first chamber 91 toward the one end 110 a of the tubular body 110. Therefore, hot oil discharged into the first chamber 91 from the opening end portion 59b of the communication passage 59 on the oil tank 100 side can be diffused in a wide range in the first chamber 91, so that the first chamber 91 itself can be It can be effectively used for cooling.

  The flow of oil from the first chamber 91 to the second chamber 92 via the tubular body 110 is continued until the oil level of the first chamber 91 and the oil level of the second chamber 92 are substantially equal. Can be continued.

  The oil sent into the crank chamber 24 lubricates the drive parts such as the piston 20 and the crankshaft 30, and at the same time is scattered by these drive parts to become oil mist. Part of the oil mist adheres to the wall surface of the crank chamber 24 and is liquefied again.

  As shown in FIG. 7, when the piston 20 further moves from the vicinity of the top dead center to the top dead center side, the opening end portion 47 a of the direct passage 47 is also opened, and the negative pressure in the crank chamber 24 acts on the direct passage 47. obtain. Then, sufficient air can be supplied to the crank chamber 24 via the direct passage 47 to generate oil mist. Further, even if a large amount of oil stays in the valve operating chamber 31, it can be returned to the crank chamber 24.

  When the piston 20 descends from the top dead center, the crank chamber 24 changes to positive pressure. When the crank chamber 24 reaches positive pressure, the reed valve 60 is easily opened, and the crank chamber 24 is the first chamber of the oil tank 100. Communicate with 91. Then, oil mist and oil are sent from the crank chamber 24 through the communication path 59 to the first chamber 91, and the pressure in the oil tank 100 is increased. When the crank chamber 24 becomes positive pressure, the one-way valves 48 and 57 prevent the oil from flowing back from the crank chamber 24 to the valve chamber 31 and the first chamber 91 of the oil tank 100 by the one-way valves 48 and 57. The passage 54 is blocked and then the open ends 47a, 54a are closed by the piston 20.

  The one-way valves 48 and 57 are not always necessary. When these one-way valves 48 and 57 are not provided, the opening end portions 47a and 54a are positioned on the top dead center side so that the opening end portions 47a and 54a can be moved before the crank chamber 24 becomes positive pressure. The direct passage 47 and the oil feeding passage 54 may be closed and closed. Further, any one of the one-way valves 48 and 57 may be used.

  By increasing the pressure in the oil tank 100, a pressure gradient is created between the oil tank 100 and the valve operating chamber 31, and oil mist accumulated in the oil tank 100 (at least in the first chamber 91) passes through the supply passage 51. To the valve train chamber 31. In the process of sending oil mist from the oil tank 100 to the valve operating chamber 31, each component of the valve operating mechanism 70 in the valve drive chamber 52 provided in the supply passage 51 is lubricated. At this time, part of the oil mist is liquefied.

  The oil liquefied in the valve drive chamber 52 can be sent to the crank chamber 24 via the return passage 66 and the direct passage 47. Therefore, it is possible to prevent oil from staying excessively in the valve drive chamber 52 and to prevent oil from flowing into the valve operating chamber 31. Further, it is possible to prevent the oil from blocking the supply passage 51.

  The oil mist supplied to the valve operating chamber 31 lubricates the valve operating mechanism provided in the valve operating chamber 31 and is sent to the crank chamber 24 through the direct passage 47. Here, even if the oil mist supplied in the valve chamber 31 is liquefied and stays, a strong negative pressure in the crank chamber 24 acts and oil can be sent into the crank chamber 24. The oil can be prevented from staying in the chamber 31. Accordingly, it is possible to suppress oil release when the blow-by gas is discharged from the valve operating chamber 31 through the breather passage 36.

  According to the present embodiment, the lubricating device 200 of the engine 6 includes a box-shaped oil case 80 that can store oil for engine lubrication, and a partition that partitions the oil case 80 into a first chamber 91 and a second chamber 92. The wall 84, the first communication passage (communication passage 59) that communicates the crank chamber 24 and the first chamber 91 whose internal pressure fluctuates due to the reciprocation of the piston 20, and the crank chamber 24 and the second chamber 92 communicate with each other. The second communication passage (the oil feeding passage 54 and the suction pipe 55) that is disposed and exposed outside the oil case 80, the one end portion 110a communicates with the first chamber 91, and the other end portion 110b is the second chamber 92. A tubular body 110 that communicates with each other. The oil in the crank chamber 24 is discharged from the crank chamber 24 through the first communication path (communication path 59) into the first chamber 91 at the time of positive pressure in the crank chamber 24, and the second oil at the time of negative pressure in the crank chamber 24. The oil in the chamber 92 is sucked through the second communication passage (the oil feeding passage 54 and the suction pipe 55), and at least a part of the oil in the first chamber 91 passes through the tubular body 110 to the second chamber 92. It reaches. Thereby, in the process in which at least a part of the oil in the first chamber 91 reaches the second chamber 92 through the tubular body 110, the heat of the oil can be released to the outside in the tubular body 110, so that the oil can be efficiently discharged. Can be cooled.

  Further, according to the present embodiment, the one end portion 110 a of the tubular body 110 is positioned higher than the other end portion 110 b of the tubular body 110. Thereby, oil can be flowed from the first chamber 91 to the second chamber 92 through the tubular body 110 by utilizing the height difference between the one end portion 110 a and the other end portion 110 b of the tubular body 110.

  Further, according to the present embodiment, the distance L1 between the one end portion 110a of the tubular body 110 and the other end portion 110b of the tubular body 110 is the discharge port of the first communication path (the opening on the oil tank 100 side of the communication path 59). It is longer than the distance L2 between the end portion 59b) and the suction port 55a of the second communication passage (the oil feeding passage 54 and the suction pipe 55). Thereby, since the length of the tubular body 110 can be made comparatively long, cooling of oil can be accelerated | stimulated.

  Moreover, according to this embodiment, the tubular body 110 has flexibility. Thereby, the tubular body 110 can be easily assembled to the oil case 80.

  Further, according to the present embodiment, the lubricating device 200 of the engine 6 includes the cooling air supply device (the blower fan 7) that is driven by the engine 6 and sends the cooling air toward the engine 6. Cooling air from the cooling air supply device (blower fan 7) hits the tubular body 110. Thereby, the cooling air can be directly applied to the tubular body 110 to cool the oil (that is, forced cooling can be performed).

  Further, according to the present embodiment, the tubular body 110 is located between the cooling air supply device (the blower fan 7) and the oil case 80. Therefore, the tubular body 110 can be cooled on the windward side of the oil case 80 by the cooling air.

  Further, according to the present embodiment, the backpack-type blower working machine (backpack-type blower 1) includes a blower fan 7 that is rotationally driven by the engine 6 having the lubricating device 200, and one of the air sucked by the rotation of the blower fan 7. A guide part that guides the part toward the engine 6, and a blowout port (end nozzle part 5 e) that blows out the remaining air sucked by the rotation of the blower fan 7. The blower fan 7 functions as a cooling air supply device, and the cooling air passing through the guide portion hits the tubular body 110. Thereby, since it is not necessary to provide a dedicated cooling fan or the like for cooling the oil, an increase in the number of parts can be suppressed.

  In the present embodiment, the tubular body 110 is made of resin, but the tubular body 110 may be made of metal (for example, copper). Since the tubular body 110 is made of metal, the heat of oil flowing through the tubular body 110 can be efficiently released to the outside through the tubular body 110.

  In this embodiment, one tubular body 110 is provided in the oil case 80, but two or more tubular bodies 110 may be provided in the oil case 80 to promote oil cooling. Further, the cooling of the oil may be promoted by increasing the length of the tubular body 110.

  Further, in the lubricating device 200 shown in FIG. 7, the oil tank 100 is provided with a liquefying portion for liquefying the oil mist discharged from the opening end portion 59 b in the vicinity of the opening end portion 59 b of the communication passage 59 in the oil tank 100. The concentration of oil mist stored in the tank 100 may be lowered. The liquefying unit may include a collision plate that attaches and liquefies oil mist discharged from the opening end 59b.

  In the present embodiment, the engine 6 is an OHV engine, but the engine 6 may be an OHC engine.

  Further, in the present embodiment, the back-loading blower (engine blower) 1 is described as an example of the “back-loading blower working machine” of the present invention, but the “back-loading blower working machine” of the present invention is the back-loaded blower 1. For example, it may be a mist blower or a dusting machine as disclosed in Japanese Patent No. 5852841.

  Moreover, the working machine to which the lubricating device 200 is applied is not limited to the above-described backpack-type blower working machine, but may be a backpack-type working machine such as a sprayer (sprayer) or a backpack-type brush cutter. Moreover, portable work machines, such as a brush cutter, a hole digger, and a concrete cutter, may be sufficient.

  Here, in the working machine to which the lubrication apparatus 200 is applied, when the above-described blower fan 7 is unnecessary, a dedicated cooling fan for cooling the engine 6 is used instead of the blower fan 7 as a crankshaft 30. The cooling air from the cooling fan may be sent toward the engine 6 and applied to the tubular body 110. In this case, the cooling fan is driven by the engine 6 corresponding to the “cooling air supply device” of the present invention. In this case, the tubular body 110 is preferably located between the cooling fan and the oil case 80.

  As can be seen from the foregoing, the foregoing embodiments are merely illustrative of the present invention, and the present invention is made by those skilled in the art within the scope of the claims in addition to those directly shown by the described embodiments. Needless to say, it includes various improvements and changes.

DESCRIPTION OF SYMBOLS 1 Back type blower 2 Frame 3 Blower unit 4 Blowing duct 5 Blower pipe 5e End nozzle part 6 Engine 7 Blower fan 9 Volute case 20 Piston 21 Cylinder 22 Cylinder block 24 Crank chamber 25 Crankcase 26 Combustion chamber 27 Cylinder head 29 Connecting rod 30 Crankshaft 54 Oil feed passage 55 Suction pipe 55a Suction port 59 Communication passage 59b Open end 80 Oil case 81 Main body 81a Bottom 82 Outer flange 83 Through hole 84 Partition wall 84a, 84b Side wall 84c Rear wall 85 Recess 86, 87 Through Holes 88 and 89 Tubular member 91 First chamber 92 Second chamber 95 Fin 100 Oil tank 110 Tubular body 110a One end 110b The other end 200 Lubricator

Claims (8)

A box-shaped oil case that can store oil for engine lubrication;
A partition wall that divides the oil case into a first chamber and a second chamber;
A first communication passage communicating the crank chamber in which the internal pressure fluctuates due to reciprocation of the piston and the first chamber;
A second communication passage communicating the crank chamber and the second chamber;
A tubular body arranged and exposed outside the oil case, having one end communicating with the first chamber and the other end communicating with the second chamber;
With
Oil in the crank chamber is discharged from the crank chamber through the first communication path into the first chamber at the time of positive pressure in the crank chamber;
Oil in the second chamber is sucked through the second communication passage during negative pressure in the crank chamber, and at least a part of the oil in the first chamber reaches the second chamber through the tubular body;
Engine lubrication device.   The engine lubricating device according to claim 1, wherein one end of the tubular body is positioned higher than the other end of the tubular body.   The distance between the one end part of the tubular body and the other end part of the tubular body is longer than the distance between the discharge port of the first communication path and the suction port of the second communication path. Alternatively, the engine lubrication device according to claim 2.   The engine lubrication device according to any one of claims 1 to 3, wherein the tubular body has flexibility.   The engine lubrication device according to any one of claims 1 to 3, wherein the tubular body is made of metal. A cooling air supply device that is driven by the engine and sends cooling air toward the engine;
The engine lubricating device according to any one of claims 1 to 5, wherein cooling air from the cooling air supply device hits the tubular body.   The engine lubrication device according to claim 6, wherein the tubular body is located between the cooling air supply device and the oil case. A blower fan that is rotationally driven by the engine having the engine lubrication device according to claim 6 or 7,
A guide portion for guiding a part of the air sucked by rotation of the blower fan toward the engine;
A blowout port that blows out the remainder of the air sucked by rotation of the blower fan;
A carrying type blower working machine having
The blower fan functions as the cooling air supply device,
A shoulder-type blower working machine in which cooling air passing through the guide portion hits the tubular body.