WO2005110684A1 - Combustion-type work tool - Google Patents

Abstract

[PROBLEMS] A technique with which exhaust gas in a combustion chamber of a combustion-type work tool can be discharged in a rational way. [MEANS FOR SOLVING PROBLEMS] A combustion-type work tool has a movable member (126) movable so as to vary the volumes of combustion chambers (121, 122), and an atmosphere chamber (171) is provided in the work tool. The volume of the atmosphere chamber (171) is increased when the movable member moves in the direction of reducing the volume of the combustion chambers, and the volume of the atmosphere chamber is reduced when the movable member moves in the direction of increasing the volume of the combustion chambers. After the completion of processing by a piston member (155), when the movable member (126) moves in the direction of increasing the volume of the atmosphere chamber (171) while reducing the volume of the combustion chamber (122), air is sucked into the atmosphere chamber (171) from the outside while exhaust gas in the combustion chamber (122) is discharged to outside the chamber, and when the movable member (126) moves in the direction of reducing the volume of the atmosphere chamber (171) while increasing the volume of the combustion chamber (122), exhaust gas remaining in the combustion chamber (121) is discharged to outside the chamber while compressing the air in the atmosphere chamber (171) to force it into the combustion chamber (121).

Description

 Specification

 Combustion work tools

 Technical field

 The present invention relates to a power tool for performing a predetermined machining operation by using a high pressure (impact force) when combustible gas is burned, that is, a combustion chamber ignition and exhaust technology in a combustion type power tool. .

 Background art

 [0002] Japanese Patent Application Laid-Open No. 2001-162561 discloses a specific example of a so-called combustion type power tool using a piston-cylinder internal combustion engine as a drive source of a power tool such as a nailing machine or a torsion force. It is disclosed in reference 1).

 Disclosure of the invention

 Problems to be solved by the invention

[0003] With respect to the combustion gas ignition mechanism and the combustion chamber power exhaust gas discharge mechanism in the above-described prior art, there is a strong demand for further improving the product value by further reducing the operation of the power tool. An object of the present invention is to provide a technique that contributes to realizing rationalization of an ignition mechanism and rationalization of exhaust gas emission in a combustion chamber in a combustion type power tool.

 Means for solving the problem

[0004] In order to achieve the above object, the inventions described in the claims are configured.

According to the present invention, a movable member movable so as to change the volume of the combustion chamber, a guide cylinder connected to the combustion chamber, a piston member slidably housed in the guide cylinder, When the movable member moves in the direction of decreasing the volume of the combustion chamber, the volume is increased, and when the movable member moves in the direction of increasing the volume of the combustion chamber, the volume is decreased. Be composed. Then, after the working operation by the piston member, when the movable member moves in the direction of increasing the volume of the atmosphere chamber while decreasing the volume of the combustion chamber, the exhaust gas in the combustion chamber is discharged to the atmosphere chamber while discharging the exhaust gas to the outside. Air is sucked in from outside, and movable members increase the volume of the combustion chamber and decrease the volume of the atmosphere chamber When moving in the direction, the air in the atmosphere chamber is compressed and pushed into the combustion chamber, and the exhaust gas remaining in the combustion chamber is discharged outside the chamber.

 [0005] According to the present invention, the exhaust gas in the combustion chamber can be discharged in two stages, that is, when the volume of the combustion chamber is reduced and when it is increased. It is possible to reduce the residual amount of the fuel as much as possible, and it is possible to enhance the cleaning effect in the combustion chamber. Also, since it is not necessary to reduce the volume of the combustion chamber to zero or close to zero, for example, when the combustion chambers are configured with a plurality of combustion chambers that communicate with each other, the exhaust gas does not matter regardless of the shape of the combustion chambers. Gas can be discharged rationally outside the room.

 According to still another aspect of the present invention, a combustion chamber, a combustion chamber wall constituting the combustion chamber, an ignition section having an ignition region facing the combustion chamber, and a power supply section for supplying electric power to the ignition section And a cylinder connected to the combustion chamber, a piston member slidably accommodated in the cylinder, and electrically connected to the power supply unit and spaced apart from the ignition unit. A combustion-type power tool having an energization control unit is configured. When the combustion chamber wall is moved to the combustible position, the energization control section contacts the ignition section with the movement of the combustion chamber wall to allow the power supply section power to energize the ignition section and perform combustion. When the chamber wall is moved to a position other than the combustible position, the power supply unit power is regulated by separating the ignition unit power.

 [0007] According to this aspect, the power supply control unit is provided between the power supply unit and the ignition unit, and the ignition control unit is configured to allow the ignition in a state of being in contact with the ignition unit. This can simplify the structure of the power tool that does not need to be communicated, and also ensures that the ignition timing is controlled properly. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The overall configuration of a nailing machine 101 according to an embodiment of the present invention is shown in FIGS. 1 to 5, and the periphery of the combustion chamber is shown in an enlarged view in FIG. FIG. 7 is a sectional view taken along the line VII-VII of FIG. The nailing machine 101 is an example of the “combustion-type power tool” in the present invention. As shown in FIGS. 1 to 5, an outer shell of the nailing machine 101 is formed by a main housing 103, an injection unit 110, a hand grip 105, and a magazine 109. Is formed. In the main housing 103, the first combustion chamber 121 and the second The firing chamber 122, the ignition device 131, the fuel injection device 141, and the drive unit 151 are accommodated. That is, nailing machine 101 according to the present embodiment is configured to have a plurality of combustion chambers including first combustion chamber 121 and second combustion chamber. In the description below, the injection unit 110 side will be described as a front side (left side in FIGS. 1 to 5), and the opposite side (right side in FIGS. 1 to 5) as a rear side.

 In the present embodiment, the first combustion chamber 121 is used as an ignition region for the air-fuel mixture, which will be described later, and the second combustion chamber 122 is used as a region for obtaining a large combustion energy required for nail driving work. It is configured to be used as The first combustion chamber 121 corresponds to the “first combustion chamber” in the present invention, and the second combustion chamber 122 corresponds to the “second combustion chamber” in the present invention.

 [0010] The first combustion chamber 121 includes a partition 123 having a circular outer shape for partitioning the first combustion chamber 121 from the second combustion chamber 122, and a substantially flat shape located on the opposite side to the second combustion chamber 122. And a circular slide end plate 129 having an end wall surface. In other words, the partition wall portion 123 has a flat surface portion 123a on the outer peripheral side and a spherical portion 123b bulging toward the second combustion chamber 122 at the center portion side. 123a is fixed in contact with the end wall surface of the slide end plate 129 in close contact. The partition 123 described above corresponds to the “partition” in the present invention. The spherical portion 123b of the partition wall portion 123 is formed to have substantially the same diameter and a hemispherical shape with the ignition portion of the ignition device 131 as a center. A large number of communication holes 125 are formed in the spherical portion 123b of the partition wall 123 in a perforated shape (see FIG. 7). The first combustion chamber 121 and the second combustion chamber 122 are in communication with each other via the communication hole 125. That is, the igniter force is also set such that the distance to each communication hole 125 is equal to each other, and when the air-fuel mixture in the first combustion chamber 121 is ignited by the igniter of the igniter 131 and burns, The combustion surface (fire surface) in one combustion chamber 121 reaches each communication hole 125 almost simultaneously. The igniter is composed of two electrodes 133a and 133b which are arranged facing each other with a predetermined gap therebetween, which will be described later.

[0011] The second combustion chamber 122 is formed as a space surrounded by a piston 155, a cylindrical slide sleeve 127, and a partition wall 123 disposed opposite to the piston 155, which constitute a driving unit. Made. The piston 155 corresponds to the “piston member” in the present invention. The top surface (the surface facing the partition wall 123) of the bistone 155 is a spherical concave portion 155a formed in a similar shape to the spherical portion 123b of the partition wall 123. The partition wall 123, the slide sleeve 127, and the slide end plate 129 are fastened and fixed to each other by a plurality of screws 128 arranged in a circumferential direction, and a cylindrical combustion chamber having a front end opened by these three members. A wall 126 is configured. That is, the slide sleeve 127 forms the peripheral wall surface of the second combustion chamber 122, the partition wall 123 forms the end wall surface of the second combustion chamber 121 and the spherical wall surface of the first combustion chamber 121, respectively. The end wall surface of the first combustion chamber 121 is constituted by 129. The combustion chamber wall 126 corresponds to the “movable member” in the present invention.

 The combustion chamber wall 126 is movable in the long axis direction (front-rear direction) of the nailing machine 101, and is connected to the contact arm 111. The contact arm 111 is normally urged forward (forward) by a spring 112 as urging means, and the combustion chamber wall 126 is also moved forward. This state is the initial state of the nailing machine 101 shown in FIG. 1, and the volume of the second combustion chamber 122 is zero or close to zero and is reduced to the state.

 [0013] On the other hand, when the nailing machine 101 is moved toward the force-pulled material W (see FIG. 2) and the contact arm 111 is pressed against the force-pulled material W (see FIG. 2), the nail is pressed by the force-pulled material. The contact arm 111 thus moved is moved in the opposite direction against the urging force of the spring 112. The backward movement of the contact arm 111 is transmitted to the slide sleeve 127. For this reason, the combustion chamber wall 126 is moved to the fixed end plate 175 that forms the end wall surface of the atmospheric chamber 171 described later, and the end of the slide end plate 129 contacts the fixed end plate 175. This state is shown in FIG.

[0014] As the combustion chamber wall 126 moves in the front-rear direction, the volume of the second combustion chamber 122 decreases or increases. As described above, the second combustion chamber 122 has a configuration in which the volume changes with the movement of the combustion chamber wall 126, and is formed by the partition wall 123 and the slide end plate 129 which are fixed to each other and move together. The first combustion chamber 121 is configured to have a steady volume whose volume does not change. That is, the combustion chamber is composed of the first combustion chamber 121 whose volume does not change even if the combustion chamber wall 126 moves back and forth, and the second combustion chamber 122 whose volume changes. ing.

 [0015] At the front end (opening end side) of the slide sleeve 127 in the combustion chamber wall 126, a small diameter portion 127a having a small inner diameter is formed. When the combustion chamber wall 126 is located at the rear end, the small diameter portion 127a has a circular flange portion 153a formed on the outer periphery of an end portion of a cylinder 153 described later and an O-ring 154 on the outer peripheral surface. Thus, the second combustion chamber 122 is hermetically sealed by sealing through. Then, when the combustion chamber wall 126 is moved forward, the small-diameter portion 127a separates from the flange portion 153a (O-ring 154) shortly after the movement starts, and the outer periphery of the O-ring 154 and the inner peripheral surface of the slide sleeve 127 are moved. The second combustion chamber 122 is a gap between the inner space 104 of the housing 103 (a gap between the housing 103 and the outer peripheral surface of the cylinder 153, and communicates with the outside of the nailing machine 101 through the gap 127b. ).

 An atmosphere chamber 171 is formed on the opposite side (rear side) of the first and second combustion chambers 121 and 122 with the slide end plate 129 interposed therebetween. The atmosphere chamber 171 is formed by a cylindrical fixed sleeve 177, a slide end plate 129 slidably fitted in the fixed sleeve 177, and a fixed end plate 175 arranged to face the slide end plate 129. It is formed as an enclosed space. Note that the fixed end plate 175 and the fixed sleeve 177 are formed integrally. The fixed end plate 175 forms the end wall surface of the air chamber 171, the fixed sleeve 177 forms the peripheral wall surface of the air chamber 171, and these two members form the cylindrical air chamber wall 173 whose front end is open. ing. The sliding surfaces of the fixed sleeve 1 77 and the slide end plate 129 are sealed via an O-ring 179.

The fixed end plate 175 is fastened to the main housing 103 together with a housing cap 106 having a large number of ventilation holes 106 b whose outer peripheral edge is disposed at the rear end of the main housing 103 by screws (not shown). Has been concluded by As described above, the atmosphere chamber 171 is a space separated and fixed from the first and second combustion chambers 121 and 122, and moves with the movement of the combustion chamber wall 126, directly with the movement of the slide end plate 129. It is set as a space where the volume changes. That is, when the slide end plate 129 moves (forwards) in the direction of decreasing the volume of the second combustion chamber 122, the volume of the atmosphere chamber 171 increases and moves in the direction of increasing the volume of the second combustion chamber 122. Atmosphere 1 The configuration is such that the volume of 71 is reduced. The maximum volume of the atmosphere chamber 171 is set to be larger than the total volume of the first and second combustion chambers 121 and 122 when the volume of the second combustion chamber 121 is maximized.

 [0018] The fixed end plate 175 in the atmosphere chamber wall 173 has a space 106a surrounded by the fixed end plate 175 and the housing cap 106 (substantially, the atmosphere, hereinafter, this space 106a is simply referred to as the atmosphere). An intake port 161 is provided for communicating the air with the atmosphere chamber 171. The intake port 161 is provided with an intake valve 163. The intake valve 163 is configured as a check valve that opens and closes the intake port 161 to suck atmospheric air into the atmosphere chamber 171, and is arranged on the atmosphere chamber 171 side. The suction valve 163 elastically deforms toward the atmosphere chamber 171 based on the pressure difference between the inside and the outside of the atmosphere chamber 171 to allow the flow of air to the atmosphere power atmosphere chamber 171 and restricts the reverse flow. Configuration. The above-described intake port 161 and intake valve 163 constitute "first valve means" in the present invention.

 [0019] The slide end plate 129 has an intake port 165 communicating the atmosphere chamber 171 and the first combustion chamber 121, and the intake port 165 is provided with an intake valve 167. The suction valve 167 is configured as a check valve that opens and closes an intake port 165 to suck the air in the atmosphere chamber 171 into the first combustion chamber 121, and is arranged on the first combustion chamber 121 side. The intake valve 167 elastically deforms toward the first combustion chamber 121 based on the pressure difference between the first combustion chamber 121 and the atmosphere chamber 171 to reduce the flow of air from the atmosphere chamber 171 to the first combustion chamber 121. It is configured to allow and restrict the reverse flow. The above-described intake port 165 and intake valve 167 constitute the “second valve means” in the present invention.

 The fixed end plate 175 in the atmosphere chamber wall 173 is provided with a rod-shaped seal member 169 that projects into the atmosphere chamber 171 at a predetermined length. The seal member 169 is disposed so as to face the intake port 165 for the combustion chamber, and when the combustion chamber wall 126 is located at the retreat end (rear end stroke end), the intake port for the combustion chamber is provided. By fitting into the 165, the intake port 165 is sealed, and in the fitted state, the front end surface is in contact with the back surface (rear surface) of the suction valve 167.

[0021] The ignition device 131 is mainly composed of an ignition plug 133 and a piezoelectric element 138 that generates a high-voltage current, and has one electrode ( An anode 133a is arranged at the center of the slide end plate 129 that forms the end wall surface of the first combustion chamber 121. The other electrode (cathode) 133b constituting the ignition portion of the ignition plug 133 is disposed at a position where the force at the center of the slide end plate 129 is also removed, and extends to the center of the first combustion chamber 121. The electrode 133a is opposed to the tip (front end) of the one electrode 133a with a predetermined gap. The ignition part of the ignition plug 133 corresponds to the “ignition part” in the present invention, and the piezoelectric element 138 corresponds to the “power supply part” in the present invention.

 One electrode 133 a is electrically connected to piezoelectric element 138 via a conductive material (metal) ball (steel ball) 134 provided on fixed end plate 175, spring 135 and electric wiring 136. Have been. That is, the ball 134 and the spring 135 constitute a part of the ignition circuit. The ball 134 is disposed so as to face the rear end of the one electrode 133a, and is brought into contact with or separated from the one electrode 133a as the combustion chamber wall 126 moves forward or backward. That is, when the combustion chamber wall 126 is moved to a position near the maximum volume of the second combustion chamber 122, the one electrode 133a is electrically connected to the ball 134 to permit ignition. When the combustion chamber wall 126 moves in the direction of decreasing the volume of the second combustion chamber 122, the electrical connection is cut off by separating from the ball 134, so that ignition is restricted. The above-described ball 134 and spring 135 constitute an “energization control unit” in the present invention. Further, the position where the volume of the second combustion chamber 122 is near the maximum corresponds to the “combustible position” in the present invention.

The ball 134 is movably fitted into a hole 137a of a holding member 137 provided on the fixed end plate 175 and having an electric insulating material strength, and is urged toward the electrode 133a by a spring 135. . As a result, when the combustion chamber wall 126 is moved rearward, the ball 134 contacts the rear end of the electrode 133a when the combustion chamber wall 126 approaches the retreat end (stroke end), and then contacts the electrode 133a. Retreat while maintaining the contact state. Thus, the spring 135 constitutes an urging means for stably holding the contact state between the ball 134 and the electrode 133a over a predetermined range. The ignition operation of the ignition device 131 is performed by deforming the piezoelectric element 138 by the drawing operation of the trigger 107 disposed on the hand grip 105, This is achieved by discharging the generated high-voltage current between the electrodes 133a and 133b. The other electrode 133b is body-grounded to the slide end plate 129. The above-described trigger 107 corresponds to “ignition operating means” in the present invention.

 The fuel injection device 141 mainly includes a pipe-shaped member 145 that extends from the first combustion chamber 121 through the partition wall 123 to the second combustion chamber 122, and the pipe-shaped member 145 includes: Fuel injection holes 143 are formed in appropriate locations facing the combustion chambers 121 and 122. The fuel injector 141 is connected to a fuel container (fuel cylinder) 149 to receive fuel. The amount of fuel injected by the fuel injection device 141 is set individually according to the effective volumes of the first combustion chamber 121 and the second combustion chamber 122.

 The pipe-shaped member 145 constituting the fuel injection device 141 is fixed to the slide end plate 129, and one end (tip) side of the inner periphery of the spherical portion 123 b of the partition wall 123 constituting the first combustion chamber 121. It extends along the surface and penetrates through the center of the spherical portion 123b and projects to the second combustion chamber 122. As shown in FIG. 7, the projecting tip 145 a of the pipe-shaped member 145 that penetrates the spherical portion 123 b and protrudes into the second combustion chamber 122, without dispersing the fuel into the second combustion chamber 122. A plurality of fuel injection holes 143 penetrating radially (radially) to be injected are provided. When the combustion chamber wall 126 moves in the direction of decreasing the volume of the second combustion chamber 122, the projecting tip 145a of the pipe-shaped member 145 is accommodated in a storage space 155b formed in the center of the top surface of the piston 155. Thus, the volume of the second combustion chamber 122 can be reduced to zero or a state close to zero.

As clearly shown in FIG. 8, the pipe-like member 145 has at least a fuel injection into the first combustion chamber 121 at a curved portion 145b arranged along the inner peripheral surface of the spherical portion 123b. It has one fuel injection hole 143. The combustion injection hole 143 is set so as to inject fuel toward an ignition portion of the ignition device 131. The other electrode 133b of the electrodes 133a and 113b constituting the ignition portion of the ignition device 131 is disposed in a protruding manner in the first combustion chamber 121, and a predetermined gap (plug gap) is formed in one of the electrodes 133a. It is configured to bend into an L-shape and extend to oppose. In the present embodiment, in order to prevent the fuel from directly falling between the plug gaps, the pipe-shaped member 145 is arranged so as to inject the fuel toward the back side of the other electrode 133b. I have. That is, the pipe-shaped member 145 The fuel force injected from the fuel injection hole 134 of the curved portion 145b is disposed so as to be injected toward the one electrode 133a with the extending portion of the other electrode 133b interposed therebetween.

As clearly shown in FIG. 8, the pipe-like member 145 has at least a fuel injection into the first combustion chamber 121 at a curved portion 145b arranged along the inner peripheral surface of the spherical portion 123b. It has one fuel injection hole 143. The combustion injection hole 143 is set so as to inject fuel toward an ignition portion of the ignition device 131. The other electrode 133b of the electrodes 133a and 113b constituting the ignition portion of the ignition device 131 is disposed in a protruding manner in the first combustion chamber 121, and a predetermined gap (plug gap) is formed in one of the electrodes 133a. It is configured to bend into an L-shape and extend to oppose. In the present embodiment, in order to prevent the fuel from directly falling between the plug gaps, the pipe-shaped member 145 is arranged so as to inject the fuel toward the back side of the other electrode 133b. I have. That is, the pipe-shaped member 145 is disposed so as to inject fuel toward one electrode 133a with the fuel force injected from the fuel injection hole 134 of the curved portion 145b sandwiching the extending portion of the other electrode 133b. The curved portion 145b of the pipe-shaped member 145 corresponds to the “portion arranged along the spherical portion” in the present invention, and the protruding tip 145a corresponds to the “portion protruding into the second combustion chamber” in the present invention. Corresponding.

 The other end (base end) of the pipe-shaped member 145 extends between the outer peripheral surface of the slide sleeve 127 and the inner peripheral surface of the fixed sleeve 177 and is supplied from the fuel container 149. The fuel supply passage member 146 for guiding the fuel is inserted into the fuel supply passage 147, and slides in the fuel supply passage 147 as the combustion chamber wall 126 moves. The supply of fuel from the fuel container 149 is performed in conjunction with the operation of pressing the contact arm 111 against the work material W to be worked.

[0029] The drive unit 151 includes a cylinder 153 housed in the main housing 103, a piston 155 slidably disposed in the cylinder 153, and a piston rod 157 integrally connected to the piston 155. Is composed mainly of. The cylinder 153 corresponds to the “guide cylinder” in the present invention. The distal end side of the piston rod 157 is connected to an injection device arranged in the injection portion 110 for driving a nail (not shown) forward. In addition, the front end inside the cylinder 153 absorbs and reduces the impact of the high-speed driven piston 155, A cushion rubber 159 for receiving 5 is appropriately arranged. Further, the cylinder 153 is provided with a check valve 113 for opening and closing a ventilation port 114 communicating the inside of the bore 153a of the cylinder 153 with the internal space 104 of the housing 103. This one-way valve 113 allows the gas in the bore 153a of the cylinder 153 to flow out into the internal space 104, while restricting the gas in the internal space 104 from flowing into the bore 153a of the cylinder 153. It is configured as

 [0030] The magazine 109 is attached to an injection portion 110 formed on the tip side of the main nozzle 103 of the nailing machine 101, and accommodates a large number of interconnected nails and removes nails to be driven. Face the injection unit 110. Since the configuration of the magazine 109 itself is well known, a detailed description thereof will be omitted for convenience.

 The above-described contact arm 111 is provided at the tip of the injection unit 110. The contact arm 111 is positioned in the longitudinal direction of the injection unit 110 (that is, in the longitudinal direction of the nailing machine 101 and corresponds to the left-right direction in FIGS. 1 to 5), and relatively to the injection unit 110. It is slidable, and is normally urged by a spring 112 toward the distal end (to the left in FIGS. 1 to 5). Note that the spring 112 also serves as a biasing means for the slide sleeve 127 described above.

 [0032] The nailing machine 101 according to the present embodiment is configured as described above. Next, the operation of the nailing machine 101 will be described. The nailing machine 101 always has the state shown in FIG. 1 as an initial state. In this initial state, the combustion chamber wall 126 is moved forward by the urging force of the spring 112, and the volume of the second combustion chamber 122 is reduced to a minimum (zero or nearly zero), and the volume of the atmosphere chamber 171 is reduced. Has been increased to the maximum. The piston 155 is located at the top dead center. Also, one electrode 133a of the ignition plug 133 is separated from the ball 134 by the force of the ball 134, and the electrical connection to the electrode 133a is cut off to restrict the ignition of the plug.

In this state, in order to perform the nail driving operation using the nailing machine 101, as shown in FIG. 2, the contact arm 111 first contacts the workpiece W, and then the worker The pressing force toward the workpiece is applied to the nailing machine 101. Then, the contact arm 111 retreats to the side away from the workpiece W while resisting the urging force of the spring 1 12. The retreating operation of the contact arm 111 causes the combustion chamber wall 126 connected to the contact arm 111 to move. Operates backward. The retreating operation of the combustion chamber wall 126 increases the volume of the second combustion chamber 122 and decreases the volume of the atmosphere chamber 171. The movement of the combustion chamber wall 126 is regulated by the outer peripheral rear end of the slide end plate 129 abutting on the outer peripheral front end surface of the fixed end plate 175 of the atmosphere chamber wall 173. At this time, the volume of the second combustion chamber 122 is set to the maximum state, and the volume of the atmosphere chamber 171 is set to the minimum state. Further, the volume of the first combustion chamber 121 and the volume of the second combustion chamber 122 are set to a predetermined volume ratio.

 When the combustion chamber wall 126 moves backward and approaches the retreat end, one of the electrodes 133 a comes into contact with the ball 134, and the piezoelectric element 138 passes through the ball 134, the spring 135 and the electric wiring 126. And it is in a state of being electrically connected. Furthermore, the seal member 169 fits into the intake port 165 for the combustion chamber to seal, and the tip of the seal member 169 contacts the back surface of the intake valve 167.

 In the retreat operation of the combustion chamber wall 126, fuel is supplied from the fuel container 149 when the combustion chamber wall 126 approaches the retreat end, and the fuel is supplied to the fuel supply passage 147 and the noise-like member 145. The fuel is then injected into the combustion chambers 121 and 122 from the fuel injection holes 143 provided in the pipe-shaped member 145 (see FIG. 7). In this case, in the present embodiment, in the first combustion chamber 121, a beg fuel that enhances the ignition effect at the time of ignition performed thereafter is supplied from the fuel injection hole 143 of the curved portion 145b of the pipe-shaped member 145 to the ignition plug. It is configured to be injected toward the center, that is, toward the ignition portion. On the other hand, in the second combustion chamber 122, fuel is radially injected into the second combustion chamber 122 from the fuel injection holes 143 at the protruding tip 145 a. The amount of fuel supplied to the first and second combustion chambers 121, 122 is set in accordance with the volumes of the respective combustion chambers 121, 122. Further, the injected fuel is mixed with the air in each of the combustion chambers 121 and 122, whereby the inside of each of the combustion chambers 121 and 122 is filled with the air-fuel mixture. This mixture corresponds to the “flammable gas” in the present invention.

[0036] Further, at the time of the retreat operation of the combustion chamber wall 126, fuel is supplied from the fuel container 149 when the combustion chamber wall 126 approaches the retreat end, and the fuel is supplied to the fuel supply passage 147 and the nove-like member 145. The fuel is supplied to the combustion chambers 121 and 122 through fuel injection holes 143 provided in the pipe-shaped member 145. In this case, in the present embodiment, in the first combustion chamber 121, a fuel that enhances the ignition effect at the time of ignition performed thereafter is supplied with an ignition fuel. Injection is directed toward the center of the gear, that is, the ignition portion. On the other hand, in the second combustion chamber 122, fuel is radially injected from the fuel injection holes 143 in the radial direction of the second combustion chamber 122. The amount of fuel supplied to the first and second combustion chambers 121 and 122 is set according to the volumes of the respective combustion chambers 121 and 122. Further, the injected fuel is mixed with the air in each of the combustion chambers 121 and 122, whereby the interior of each of the combustion chambers 121 and 122 is filled with the air-fuel mixture. This mixture corresponds to “flammable gas” in the present invention.

After the retracting operation of the contact arm 111, when the operator pulls down the trigger 107 provided on the hand grip 105, the ignition operation by the ignition device 131 provided in the first combustion chamber 121 is performed. As a result, the ignition and combustion operation in the first combustion chamber 121 is realized smoothly and with high efficiency.

 When the ignition device 131 performs an ignition operation, as shown in FIG. 3, the air-fuel mixture filled in the first combustion chamber 121 is ignited from the vicinity of the ignition section, and the mixture in the first combustion chamber 121 is ignited. The combustion of the gas starts. The combustion effect of the air-fuel mixture is explosive, and the combustion surface (fire surface) of the air-fuel mixture reaches the partition 123 in a very short time. At this time, in the present embodiment, since the partition wall portion 123 is formed as a spherical portion 123b having a substantially equal diameter centered on the ignition portion, the combustion surface of the air-fuel mixture that also generates the ignition portion force is formed by the ignition portion. Reaches the spherical surface portion 123b having the same radius with respect to. For this reason, the ignition timing of the second combustion chamber 122 can be standardized for each communication hole 125 over the entire boundary surface of the partition wall 123, and the combustion start timing in the second combustion chamber 122 can be effectively reduced. It is possible to control it.

 The air-fuel mixture filled in the second combustion chamber 122 is simultaneously ignited from the entire surface area of the partition wall 123 through the respective communication holes 125, and the combustion of the air-fuel mixture in the second combustion chamber 122 starts. Is done. The volume of the second combustion chamber 122 is set to be larger than the volume of the first combustion chamber 121, and the combustion of the air-fuel mixture in the second combustion chamber 122 generates a large combustion pressure. As a result, the piston 155 is slidably moved (forward) in the cylinder 153 toward the workpiece.

When the piston 155 slides inside the cylinder 153, the internal space of the cylinder 153 on the piston rod 157 is reduced by the sliding operation. Since the fluid is discharged to the outside (the internal space 104 of the housing 103) through the check valve 113, the sliding operation of the biston 155 is not hindered. Further, when the first combustion chamber 121 is burned, the inside of the first combustion chamber 121 is in a considerably high pressure state. However, in the present embodiment, the suction valve is formed by the seal member 169 inserted into the intake port 165 for the combustion chamber. By supporting the back of the 167, it protects the intake valve 167 from being deformed or damaged by high pressure during combustion, improves the durability of the intake valve 167, and reduces the gas in the first combustion chamber 121. It can be prevented from flowing out from the intake port 165 to the atmosphere chamber 171 beforehand.

 As the piston 155 slides in the cylinder 153, the piston rod 157 moves linearly in the direction of the workpiece, thereby causing the nail set in the injection unit 110 to be heated. It is injected and driven at high speed to the material side. At this time, the piston 155 that has moved at a high speed in the cylinder 153 in the direction of the workpiece comes into contact with the cushion rubber 159, and its kinetic energy is absorbed and reduced, and the piston 155 stops. That is, the piston 155 reaches the bottom dead center and stops. This state is shown in FIG. When the piston 155 passes through the check valve 113 when moving to the bottom dead center of the piston 155, the exhaust gas in the first and second combustion chambers 121 and 122 used for the forward movement of the piston 155 is provided. The gas is discharged outside the room (the internal space 104 of the nozzle 103) through the check valve 113.

 [0042] At the stage where the nail driving operation is completed, the exhaust gas is discharged from the check valve 113, and a contraction cooling action is generated in the first and second combustion chambers 121 and 122. As a result, a negative pressure is generated in the first and second combustion chambers 121 and 122, and a suction action is generated. For this reason, the piston 155 automatically starts the retreating operation to the side away from the workpiece W. At this time, in the present embodiment, since the intake port 165 for the combustion chamber is sealed by the seal member 169, air is prevented from flowing from the atmosphere chamber 171 into the first combustion chamber 121, and the piston 155 Can be reliably returned to the initial position.

[0043] Further, by releasing the pressing load on the nailing machine 101 that had been acting in the direction of the workpiece, the operator relatively retracted toward the main nozing 103 as shown in FIG. The contact arm 111 moves forward (toward the material to be kneaded) via the biasing force of the spring 112. As the contact arm 111 moves forward, the combustion chamber wall 126 moves forward (toward the piston 155). Thus, the small diameter portion 12 of the slide sleeve 127 of the combustion chamber wall 126 7a is separated from the flange portion 153a of the cylinder 153, and a gap 127b is formed between the inner peripheral surface of the slide sleeve 127 and the outer peripheral surface of the flange portion 153a. , And an inner space 104) of the housing 103.

By the way, the forward movement of the combustion chamber wall 126 in the direction of the tip is controlled by the timing at which the worker releases the pressing load on the nailing machine 101 in the direction of the workpiece. The forward movement of the chamber wall 126 is performed after the backward movement of the piston 155 is completed. That is, the retreating operation of the piston 155 is instantaneously performed by the suction force (negative pressure) generated in the first and second combustion chambers 121 and 122 due to the cooling operation. Therefore, as long as the operator normally releases the pressing force of the nailing machine 101 toward the workpiece, the piston 155 ends the retreating operation before the forward movement of the combustion chamber wall 126 is started. To the initial position (see Fig. 4) before starting the forward movement. At this point, as described above, since the intake port 165 for the combustion chamber is sealed by the seal member 169, the inflow of air from the atmosphere chamber 171 to the first combustion chamber 121 is suppressed. In addition, the negative pressure state of the second combustion chambers 121 and 122 is maintained, and the piston 155 can be reliably returned to the initial position.

 [0045] By the forward movement of the combustion chamber wall 126, as shown in Fig. 4, the volume of the second combustion chamber 122 is reduced, and the space between the inner peripheral surface of the slide sleeve 127 and the outer peripheral surface of the flange portion 153a is reduced. The second combustion chamber 122 is communicated with the outside through the gap 127b. Then, the exhaust gas in the second combustion chamber 122 is discharged outside through the gap 127b as the volume of the second combustion chamber 122 is reduced. On the other hand, the forward movement of the combustion chamber wall 126 moves the slide end plate 129 away from the fixed end plate 175, thereby increasing the volume of the atmosphere chamber 171 and at the same time, moving the seal member 169 from the combustion chamber intake port 165. The air exits and the intake port 165 is opened. Further, one electrode 133a is separated from the ball 134, and the electrical connection is cut off.

As the volume in the atmosphere chamber 171 increases, the pressure in the atmosphere chamber 171 decreases accordingly. As a result, due to the pressure difference between the pressure in the atmosphere chamber 171 and the atmospheric pressure in the housing cap 106, the air in the housing cap 106 is sucked by pushing the intake valve 163 out of the suction port 161 for the atmosphere chamber. . At this time, the intake valve 167 for the combustion chamber is brought into close contact with the peripheral portion of the intake port 165 for the combustion chamber, and the exhaust gas in the first combustion chamber 121 flows into the atmosphere chamber 171. Prevent spillage (leakage). When the combustion chamber wall 126 reaches the forward end (stroke end), the volume of the second combustion chamber 122 becomes minimum (zero), and the exhaust gas in the second combustion chamber 122 is discharged outside the chamber. The capacity of the atmosphere chamber 171 is maximized, and fresh air is stored in the atmosphere chamber 171. That is, it returns to the initial state shown in FIG. At the time of the return to the initial state, the distal end protruding portion 145a of the pipe-shaped member 145 protruding into the second combustion chamber 122 is accommodated in the storage space 155b provided in the piston 155.

 Subsequently, when the contact arm 111 is pressed against the workpiece W to perform nailing operation, the combustion chamber wall 126 is moved backward as described above. This state is shown in FIG. The retreating operation of the combustion chamber wall 126 increases the volume of the second combustion chamber 122 and decreases the volume of the atmosphere chamber 171, so that the air in the atmosphere chamber 171 is compressed and the intake air for the combustion chamber is reduced. The suction valve 167 is pushed away from the port 165 and is forcibly pushed into the first combustion chamber 121. As a result of the forced pushing of the air into the first combustion chamber 121, the exhaust gas remaining in the first combustion chamber 121 is pushed out through the communication hole 125 to the second combustion chamber 122, and further the gap 127b is formed. After that, it is discharged outside the room. That is, the exhaust gas remaining in the first combustion chamber 121 is pushed out to the second combustion chamber 122 by the air flowing from the atmosphere chamber 171 and then discharged to the outside, and is discharged outside the first and second combustion chambers 121 and 121. A so-called scavenging of 122 will be performed. In this case, since a large number of communication holes 125 are arranged in the spherical portion 123b of the partition wall portion 123, air flows substantially uniformly throughout the second combustion chamber 122. By virtue of this, in the first and second combustion chambers 121 and 122, the exchange of the exhaust gas with the air is smoothly performed, and the residual amount of the exhaust gas is reduced. As a result, especially when nailing work is performed continuously, it is necessary to optimize the mixing ratio of fuel and air to be injected into the first and second combustion chambers 121, 122 next time. Becomes effective.

When the combustion chamber wall 126 reaches the retreat end (the state shown in FIG. 2), the inside of the first and second combustion chambers 121 and 122 is filled with fresh air. In this case, in the present embodiment, the maximum volume of the large air chamber 171 is set to be larger than the maximum total volume of the first and second combustion chambers 121 and 122. As a result, air having a volume larger than those volumes is sent into the first and second combustion chambers 121 and 122, and the exhaust gas in the first and second combustion chambers 121 and 122 is reliably discharged to the outside. And can be replaced with fresh air. When the combustion chamber wall 126 reaches the retreat end, the electrode (anode) 133 a contacts the ball 134, and is electrically connected to the piezoelectric element 138 via the ball 134, the spring 135, and the electric wiring 126. The ignition operation is allowed. In addition, the seal member 169 is inserted into the intake port 165 for the combustion chamber to seal the intake port 165, and comes into contact with the back surface of the intake valve 167 to prepare for the action of high pressure on the intake valve 167. Further, the outer peripheral surface of the flange 153a of the inner cylindrical surface 153 of the / J diameter 127a of the slide sleeve 127 is slidably contacted with the outer peripheral surface of the flange 153a via the O-ring 154, and the gap 127b is closed. Thereby, the second combustion chamber 122 is made a closed space. When the trigger 107 is pulled and squeezed in this state, the operation described above is repeated, and the nailing operation is performed.

 As described above, according to the present embodiment, in the combustion chamber structure having the first combustion chamber 121 whose volume does not change and the second combustion chamber 122 whose volume changes, the combustion chamber wall 126 is After the exhaust gas in the second combustion chamber 122 is exhausted to the outside, the air taken into the atmosphere chamber 171 is forced into the first combustion chamber 121. The exhaust gas remaining in the first combustion chamber 121 is discharged from the first combustion chamber 121 to the outside through the second combustion chamber 122. As a result, the exhaust gas in the first and second combustion chambers 121 and 122, which does not change the volume of the first combustion chamber 121, is efficiently discharged to the outside, and the first and second combustion chambers 121 and 122 are effectively exhausted. It is possible to fill the inside with fresh air.

That is, in the present embodiment, in the nailing machine 101 in which the combustion chamber is composed of the first and second combustion chambers 121 and 122, the first combustion chamber 121 is designed to improve the combustion efficiency of the air-fuel mixture. A spark plug 133 is provided, and the partition wall 123 is provided with an ignition portion so that the combustion surface of the air-fuel mixture ignited by the ignition unit in the first combustion chamber 121 reaches the communication hole 125 of the partition wall 123 at substantially the same time. It has a configuration having a spherical portion 123b with an equal radius at the center. With such a configuration, it is difficult to change (decrease) the volume of the first combustion chamber 121 to discharge the exhaust gas. However, according to the present embodiment, the second combustion chamber 121 Exhaust while maintaining the configuration in which the shape of the partition 123 forming the first combustion chamber 121 is formed to be hemispherical, which improves the combustion efficiency of the air-fuel mixture by efficiently injecting the flame into the combustion chamber 122. The gas discharge function can be effectively performed. [0052] In this case, since the maximum volume of the atmosphere chamber 171 is set to be larger than the total volume of the first and second combustion chambers 121 and 122, those volumes are stored in the first and second combustion chambers 121 and 122. By sending more air, the exhaust gas and air can be exchanged reliably. If the nailing operation is performed continuously, that is, if the volume of the second combustion chamber 122 repeatedly decreases and increases within a short time, the exhaust gas discharged from the second combustion chamber 122 Gas may be present around the outlet. Then, when the volume of the second combustion chamber 122 is increased, the exhaust gas may be sucked into the combustion chamber again, that is, may flow backward. In the present embodiment, V and so-called backflow prevention means are configured by sending air having a volume larger than the volume of the first and second combustion chambers 121 and 122, so that the exhaust gas Backflow into the combustion chamber can be reliably prevented. Further, in the present embodiment, the first combustion chamber 121 has a stationary configuration in which the volume does not change, so that the ignition device 131 or the pipe-shaped member 145 for supplying fuel is provided in the center of the first combustion chamber 121. Can be set. Thereby, the flame (combustible gas combustion surface) generated in the first combustion chamber 121 can be uniformly and efficiently injected into the second combustion chamber 122.

 Further, in the present embodiment, when the combustion chamber wall 126 is moved to the retreat end, the sealing member 169 is inserted into the combustion chamber intake port 165 to seal the intake port 165. are doing. Therefore, during the combustion of the first and second combustion chambers 121 and 122, the predetermined performance is maintained by suppressing the loss of combustion energy due to the gas in the first combustion chamber 121 leaking to the atmosphere chamber side. Also, during contraction cooling in the first and second combustion chambers 121 and 122 (at the time of negative pressure), the air in the atmosphere chamber 171 is prevented from flowing into the first combustion chamber 121 to move the piston 155 to the initial position. It is possible to reliably return to.

Further, in the present embodiment, ball 134 electrically connected to piezoelectric element 138 is arranged so as to face one electrode 133a constituting the ignition portion, and combustion chamber wall 126 is retracted. When moving to the vicinity of the end, the electrode 133a is brought into contact with the electrode 133a to allow current to flow.When the combustion chamber wall 126 is located at a position forward of the vicinity of the retreat end, the electrode 133a should be separated from the electrode 133a. In this configuration, the current supply to the electrode 133a is regulated. By employing such a configuration, the first and second combustion chambers 121 and 122 are empty. In the nailing machine 101 configured to move the combustion chamber wall 126 to introduce air or discharge exhaust gas, it is possible to rationally supply power to the ignition unit while enabling cordless operation for the ignition unit. Can be. In the nailing machine 101 in which the combustion chamber wall 126 moves, if the piezoelectric element 138 and the electrode 133a of the ignition section are directly connected by electric wiring, the electric wiring is It is necessary to set the slack part necessary to allow the movement, and to secure the accommodation space on the housing side to accommodate the slack part of the electric wiring. However, according to the present embodiment, the brute force problem can be solved, and the ignition portion, and furthermore, the combustion chamber wall 126 can be largely moved without being restricted by the cord.

 In the present embodiment, when the combustion chamber wall 126 moves near the retreat end, that is, when the combustible gas is filled in the first and second combustion chambers 121 and 122, the combustion of the combustible gas When the ignition is required, the electrode 133a can be energized, so that ignition in the first combustion chamber 121 can be reliably performed at the time when ignition is required. Become. Further, in this embodiment, the ball 134 and the spring 135 for urging the ball 134 are used as current-carrying members, respectively, and the ball 134 is configured to follow the electrode 133a in a predetermined range together with the electrode 133a in contact with the electrode 133a. . As a result, the width of the energization region can be increased, and the power supply operation can be stabilized. In addition, the impact at the time of contact between the electrode 133a and the ball 134 can be absorbed by the elastic deformation of the spring 134, and the power supply function can be maintained even if wear progresses.

In the present embodiment, the inner wall surface (end slide plate 129) of the first combustion chamber 121 in the long axis direction is formed by a flat surface, and the ignition portion is disposed at the center thereof. With the center position as a reference position, for example, a tapered or curved concave portion is formed so as to face the piston 155 side toward the periphery of the inner wall surface. May be substantially flush with each other, that is, a substantially flat surface may be formed. According to the configuration described above, the igniting portion that actually ignites the flammable gas is connected to the concave portion of the inner wall surface in a flush manner, so that the combustion surface of the flammable gas has a concave shape from the start of ignition. It is possible to smoothly guide the partition wall 123 side (that is, the piston 151 side) along the inner wall surface. In the present embodiment, the nailing machine 101 having a configuration in which the combustion chamber is divided into the first and second combustion chambers 121 and 122 has been described, but a single combustion chamber is formed. It may be applied to a nailing machine with a configuration. Further, in the present embodiment, for example, a ring-shaped or sleeve-shaped current-carrying member is provided in place of the force constituted by the ball 134 and the spring 135 serving as the conductive material, and the current-carrying control section is provided with the electrodes 133a. It is also possible to adopt a configuration in which energization is allowed by inserting a. In the present embodiment, the configuration is such that the energization of the igniter is permitted by direct contact of the ball 134 with the electrode 133a, but a configuration in which the ball 134 directly contacts the electrode 133a may be employed. As one example, a conductive piece whose one end is connected to one electrode 133a, which is directly on the slide end plate 129 of the combustion chamber wall 126, is appropriately set via a bracket, and is connected to the other end of the conductive piece. A terminal is set, and the terminal and a current-carrying member such as a ball are arranged to face each other, and the contact or separation between the terminal and the current-carrying member allows or restricts current supply to the ignition part. In addition, the present embodiment is applicable to the force described in the case of the nailing machine, that is, the tacking force used for the so-called stable driving operation.

 Further, in the present embodiment, the projecting tip 145a of the pipe-shaped member 145 that penetrates the spherical portion 123b and projects into the second combustion chamber 122 is indicated by the center line of the projecting tip 145a. The fuel is arranged so as to be located on a center line extending in the longitudinal direction through the center of the second combustion chamber 122, and as shown in FIG. 7, fuel is injected from a fuel injection hole 143 provided at the projecting tip 145a. Injection is performed in the radial direction of the second combustion chamber 122. Therefore, the fuel can be uniformly supplied over the entire circumferential region in the second combustion chamber 122 without unevenness. As a result, the fuel and air are efficiently mixed, and the combustion efficiency can be improved. In addition, the combustion pressure generated by combustion is equalized in the circumferential area in the combustion chamber, so that the combustion energy in the combustion chamber is transmitted to the piston member with good non-lance, and stable driving of the piston member is realized. Is done.

In the present embodiment, the piston 155 is provided with a storage space capable of accommodating the distal end protruding portion 145a of the pipe-shaped member 145, so that the distal end protruding when the volume of the second combustion chamber 122 is reduced is provided. The interference of the part 145a with the piston 155 can be avoided. In particular, according to the present embodiment, a configuration in which distal end protruding portion 145a is arranged on the center line of second combustion chamber 122 is provided. As a result, the storage space 155b is also set at the axial center of the piston 155 in accordance with this arrangement. Therefore, even after the piston member is assembled, even if the piston member moves in the circumferential direction, the position of the storage space does not substantially change, and the problem of positional displacement does not occur. For this reason, it is possible to improve the assemblability of the piston member.

 Further, in the present embodiment, a fuel that improves the ignitability of the combustible gas when discharged between electrodes 133a and 133b of ignition device 131 is injected toward the ignition portion of ignition device 131. In the configuration, as shown in Fig. 8, the fuel is injected toward the back of the electrode 133b, so that a large amount of lubricating oil mixed in the fuel directly falls on the discharge section at the tip of the electrode. It is possible to avoid the adverse effects caused by this.

 In the present embodiment, a portion of slide end plate 129 that faces spherical portion 123 b of partition wall 123, that is, the mounting surface of ignition plug 133 is formed as a flat surface. It may be formed by a spherical concave surface. In this case, it is preferable to set the center of the concave surface so as to be the deepest portion, and to install the ignition plug 133 at the portion. Further, in the present embodiment, the suction valve 163 for the combustion chamber and the suction valve 167 for the atmosphere chamber are each constituted by a reed valve. One or both of the suction valves 163 and 167 are spool valves. It's composed of

 In the present embodiment, by setting the volume of the atmosphere chamber 171 to be larger than the total volume of the first and second combustion chambers 121 and 122, a means for preventing backflow of exhaust gas into the second combustion chamber 122 is provided. However, the backflow prevention means may be constituted by a method different from the method of changing the capacity of the atmosphere chamber 171 and the first and second combustion chambers 121 and 122. Although this embodiment has been described in connection with a nailing machine, it is applicable to a so-called tack force used in a stable driving operation.

 (Modification Example Regarding Ignition Device)

9 and 10 show modifications of the configuration of the ignition device 131. In this modification, an electrode holding portion 234 capable of holding one electrode 133a in a linear shape (or a planar shape) is used instead of the ball 134 and the spring 135 described above. The electrode holding portion 234 has a neck-shaped bent portion 235 that is electrically connected to a piezoelectric element 138 (not shown) (see FIG. 1 and the like) and that applies an elastic force so as to sandwich the electrode 133a. . And As shown in FIG. 10, when the combustion chamber wall 126 retreats and moves to make the volume of the second combustion chamber 122 close to the maximum, one electrode 133a is moved to the bent portion 235 of the electrode holding portion 234. Will be retained. At this time, the electrode 133a is linearly (or planarly) brought into contact with the bent portion 235 by being inserted between a pair of bent portions 235 formed long in the longitudinal direction of the electrode 133a. At the same time, the bent portion 235 exerts an elastic force so as to clamp the electrode 133a. Therefore, the electrode holding section 234 can hold the electrode 133a firmly. In short, the one electrode 133a is electrically connected to the piezoelectric element 138 through the electrode holding part 234, so that a discharge occurs between the electrodes 133a and 133b.

 Brief Description of Drawings

 FIG. 1 is a partial front sectional view showing the entire configuration of the nailing machine according to the present embodiment, showing an initial state in which a biston is located at a top dead center.

 FIG. 2 is a partial cross-sectional front view showing the entire configuration of the nailing machine, showing a state in which the volume of the second combustion chamber is maximized by the retraction of the combustion chamber wall.

 FIG. 3 is a partial cross-sectional front view showing the entire configuration of the nailing machine, showing a nailing completed state in which the piston has been moved to the bottom dead center.

 [4] FIG. 4 is a partial front cross-sectional view showing the entire configuration of the nailing machine, showing an exhaust state of exhaust gas from the second combustion chamber.

 FIG. 5 is a partial front sectional view showing the entire configuration of the nailing machine, showing the state of exhaust of residual exhaust gas in the first combustion chamber.

 FIG. 6 is an enlarged sectional view of a periphery of a combustion chamber.

 FIG. 7 is a sectional view taken along line VII-VII in FIG. 6.

 FIG. 8 is an enlarged cross-sectional view of the periphery of the combustion chamber, showing a state where the volume of the second combustion chamber is maximized.

 FIG. 9 is a partial cross-sectional view showing a configuration of a modified example of the ignition device.

 FIG. 10 is a partial cross-sectional view showing a configuration of a modified example of the same ignition device.

 Explanation of symbols

[0065] 101 nailing machine (combustion type work tool)

103 Main housing 104 Interior Space

 105 hand grip

 106 Housing cap

 106a space

 106b vent

 107 Tririga

 109 Magazine

 110 Injection unit

 111 Contact arm

 113 Check valve

 114 vent

 121 1st combustion chamber (1st combustion chamber) 122 2nd combustion chamber (2nd combustion chamber) 123 Partition wall (partition)

123a Flat surface

123b spherical part

125 communication hole

 126 Combustion chamber wall (movable member) 127 Slide sleeve

127a Small diameter part

127b gap

128 screws

 129 Slide end plate 131 Ignition device

133 Ignition plug

133a One electrode

133b the other electrode

134 balls 135 spring

136 electrical wiring

137 Holding member

138 Piezoelectric element

141 Fuel Injector

143 Fuel injection hole

145 Pipe-shaped member

145a Projecting tip

146 Fuel passage component 147 Fuel supply passage

149 Fuel container

151 drive

 153 Cylinder (guide cylinder) 153a Flange 咅

154 O-ring

 155 Piston (Piston 咅); 155a Spherical recess

155b storage space

157 Piston rod

159 Cushion rubber 161 Inlet for air chamber 163 Inlet valve (first valve means) 165 Inlet for combustion chamber 167 Inlet valve (second valve means) 169 Seal member

171 Atmosphere Chamber

173 Atmosphere Chamber Wall

175 Fixed end plate 177 Fixed slot 179 O-ring

Claims

The scope of the claims  [1] combustion chamber,  A movable member movable to change the volume of the combustion chamber,  A guide cylinder connected to the combustion chamber;  A piston member slidably housed in the guide cylinder,  When the volume of the combustion chamber is increased, a combustion-type power tool that performs a predetermined machining operation by moving the piston member forward by a combustion pressure generated by burning fuel in the combustion chamber. So,  When the movable member moves in the direction of decreasing the volume of the combustion chamber, the volume is increased, and when the movable member moves in the direction of increasing the volume of the combustion chamber, the atmosphere chamber has a reduced volume. And  After the working operation by the piston member, when the movable member moves in a direction to increase the volume of the atmosphere chamber while decreasing the volume of the combustion chamber, exhaust gas in the combustion chamber is discharged to the outside while the movable member moves in the direction of increasing the volume of the atmosphere chamber. When air is sucked into the atmosphere chamber from the outside and the movable member moves in a direction to decrease the volume of the atmosphere chamber while increasing the volume of the combustion chamber, the air in the atmosphere chamber is compressed. A combustion-type work tool, wherein exhaust gas remaining in the combustion chamber is discharged outside the chamber while being pushed into the combustion chamber.  [2] The combustion-type power tool according to claim 1,  A contact arm is provided on the distal end side of the tool main body, and is normally urged toward the distal end side, and is relatively retracted with respect to the tool main body by being pressed against a workpiece. And The movable member moves in the direction of decreasing the volume of the atmosphere chamber while increasing the volume of the combustion chamber by the retreating operation of the contact arm based on the pressing of the contact arm against the workpiece, while the contact member moves in the direction of decreasing the volume of the atmosphere chamber. When the pressing of the arm against the workpiece is released, the contact arm is advanced to the distal end side so that the volume of the combustion chamber is reduced and the volume of the atmosphere chamber is moved in a direction of increasing the volume. Combustion-type power tool characterized by V [3] The combustion power tool according to claim 1 or 2,  The combustion chamber is divided by a partition into a first combustion chamber whose volume does not change and a second combustion chamber whose volume changes, and the first combustion chamber and the second combustion chamber are connected to the partition. When the movable member moves in a direction to reduce the volume of the second combustion chamber, exhaust gas in the second combustion chamber is discharged to the outside while the movable member moves to the outside of the atmosphere chamber. When the movable member moves in a direction to increase the volume of the second combustion chamber, the air in the atmosphere chamber is compressed and pushed into the first combustion chamber. A combustion-type power tool, characterized in that exhaust gas in the first combustion chamber is discharged outside through the second combustion chamber.  [4] The combustion-type power tool according to claim 3,  The first combustion chamber has an ignition section for burning fuel supplied to the first combustion chamber, the partition has a spherical portion centered on the ignition section, A combustion system characterized in that when the fuel in the first combustion chamber is burned by the igniter, the combustion surface of the fuel in the first combustion chamber reaches each of the communication holes substantially simultaneously. Work tools.  [5] The combustion-type power tool according to any one of claims 1 to 4,  The atmosphere chamber communicates with the outside via first valve means that allows air to flow into the atmosphere chamber from the outside and regulates the reverse flow, and the combustion chamber includes air in the atmosphere chamber. A combustion-type power tool, wherein the power tool is connected to the atmosphere chamber through second valve means for allowing the gas to flow into the combustion chamber and restricting the reverse flow.  [6] The combustion-type power tool according to claim 5,  A combustion-type power tool, comprising: a sealing member that seals an intake port that communicates the atmosphere chamber with the combustion chamber when the combustion chamber has a maximum volume due to movement of the movable member.  [7] The combustion-type power tool according to any one of claims 1 to 6, When the movable member moves in the direction of decreasing the volume of the atmosphere chamber while increasing the volume of the combustion chamber, backflow prevention for preventing exhaust gas discharged from the combustion chamber from flowing back into the combustion chamber A combustion-type power tool having means. [8] The combustion-type power tool according to claim 7,  The backflow prevention means is configured by setting the volume of the atmosphere chamber to be larger than the volume of the combustion chamber. [9] The combustion power tool according to any one of claims 1 to 8,  The movable member is arranged between the combustion chamber and the atmosphere chamber to form walls of both chambers,  A combustion-type power tool, wherein a change in the volume of the combustion chamber caused by the movement of the movable member and a change in the volume of the atmosphere chamber are in a corresponding relationship. [10] The combustion power tool according to any one of claims 1 to 9,  The volume of the air sent from the atmosphere chamber to the combustion chamber is set to be larger than the total capacity of the combustion chamber, whereby the exchange of the exhaust gas and the air in the combustion chamber is ensured. A combustion-type power tool characterized in that: [11] The combustion-type power tool according to any one of claims 1 to 10,  The movable member has a fuel chamber wall movably forming a combustion chamber for introducing air into the combustion chamber or discharging exhaust gas,  Furthermore, while having an ignition region facing the combustion chamber, the combustion chamber wall is moved to a combustible position enabling combustion of the combustible gas in the combustion chamber, and the combustible gas is discharged in the combustion chamber. An ignition section for burning;  A power supply unit for supplying power to the ignition unit,  A power supply control unit electrically connected to the power supply unit and spaced apart from the ignition unit;  When the combustion chamber wall is moved to the combustible position, the energization control section contacts the ignition section as the combustion chamber wall moves to energize the power supply section to the ignition section. And that when the combustion chamber wall is moved to a position other than the combustible position, the combustion chamber wall is separated from the igniter to restrict energization from the power supply unit to the igniter. Combustion-type power tool. [12] The combustion-type power tool according to claim 11, The energization control unit is configured to be movable in the same direction as the movement direction of the combustion chamber wall. A power supply control unit movable member that separates or comes into contact with the ignition unit that moves together with the combustion chamber wall, and an urging member that constantly urges the power supply control unit movable member toward the ignition unit. The electric power control unit movable member and the urging member are each formed of a conductive material.  [13] The combustion-type power tool according to claim 11 or 12,  A contact arm that is disposed on the distal end side of the tool main body, is always urged toward the distal end side, and is relatively moved backward with respect to the tool main body by being pressed against a workpiece;  Ignition operation means for operating the ignition of the ignition unit,  The retraction operation of the contact arm based on the pressing of the contact arm against the material to be moved causes the combustion chamber wall to move to a combustible position, whereby the energization control unit contacts the ignition unit. A combustion-type power tool, wherein electric power of the power supply unit is supplied to the ignition unit by an ignition operation by an ignition operation unit.  [14] The combustion-type power tool according to any one of claims 11 to 13,  A combustion-type power tool, wherein the combustion wall in which the ignition region is provided has a concave surface, and the ignition region is set to be the deepest portion of the concave surface. [15] The combustion-type power tool according to any one of claims 11 to 14, wherein  A combustion-type power tool, wherein one of the power supply control unit and the ignition unit is configured to be able to contact the other linearly or planarly. [16] The combustion-type power tool according to claims 11 to 15,  The energization control unit includes an ignition unit holding unit that linearly or planarly contacts the ignition unit when the ignition unit comes into contact, and that clamps the ignition unit in an irregular shape. Combustion work tool. [17] combustion chamber,  A combustion chamber wall constituting the combustion chamber;  An ignition section having an ignition area facing the combustion chamber; A power supply unit for supplying power to the ignition unit, A cylinder connected to the combustion chamber;  A piston member slidably housed in the cylinder,  The combustion chamber wall is configured to move to introduce air into the combustion chamber or discharge exhaust gas,  In a state in which the combustion chamber wall is moved to a combustible position where the combustible gas can be burned in the combustion chamber, the combustible gas is burned by the ignition section in the combustion chamber, and the combustion generated thereby. A combustion-type power tool for performing a predetermined machining operation by moving the piston member forward by pressure and performing a predetermined machining operation,  An energization control unit electrically connected to the power supply unit and spaced apart from the ignition unit;  When the combustion chamber wall is moved to the combustible position, the energization control section contacts the ignition section as the combustion chamber wall moves to energize the power supply section to the ignition section. And that when the combustion chamber wall is moved to a position other than the combustible position, the combustion chamber wall is separated from the igniter to restrict energization from the power supply unit to the igniter. Combustion-type power tool.  [18] The combustion-type power tool according to claim 17, wherein  The energization control unit is configured to be movable in the same direction as the direction of movement of the combustion chamber wall, and to move or separate from or contact the ignition unit that moves with the combustion chamber wall; And a biasing member for constantly biasing the movable member toward the ignition portion, wherein the movable member and the biasing member are each formed of a conductive material.  [19] The combustion-type power tool according to claim 17 or 18, wherein  A contact arm that is disposed on the distal end side of the tool main body, is always urged toward the distal end side, and is relatively moved backward with respect to the tool main body by being pressed against a workpiece;  Ignition operation means for operating the ignition of the ignition unit, The combustion chamber wall is moved to a combustible position by a retreating operation of the contact arm based on the pressing of the contact arm against the material to be heated, whereby the energization control unit is moved. A combustion-type power tool, characterized in that, in a state in which the electric power is in contact with the ignition part, the electric power of the power supply part is supplied to the ignition part by an ignition operation by the ignition operation means.  [20] The combustion-type power tool according to any one of claims 17 to 19,  The fuel cell system has a partition partitioning the combustion chamber into a first combustion chamber and a second combustion chamber, and the ignition unit is disposed in the first combustion chamber, and the partition has a spherical surface centered on the ignition unit. And a plurality of communication holes disposed in the spherical portion for communicating the first combustion chamber and the second combustion chamber, and the igniting portion is provided with flammable gas in the first combustion chamber. A combustion-type power tool, characterized in that when combusted, the combustion surface of the combustible gas in the first combustion chamber reaches each of the communication holes substantially simultaneously. [21] The combustion-type power tool according to any one of claims 17 to 20,  A combustion-type power tool, wherein one of the power supply control unit and the ignition unit is configured to be able to contact the other linearly or planarly. [22] The combustion-type power tool according to claims 17 to 21,  The energization control unit includes an ignition unit holding unit that linearly or planarly contacts the ignition unit when the ignition unit comes into contact, and that clamps the ignition unit in an irregular shape. Combustion work tool.