Work machine

Abstract

Provided is a work machine that makes it possible to improve the convenience of a work machine. The present invention comprises: an ejection section that supports a nail; a drive mechanism that applies striking force to the nail supported by the ejection section; a housing 21 that houses at least part of the ejection section and the drive mechanism and has first to fourth openings OP1-OP4; and a labyrinth mechanism 70 that is provided to the housing 21 and inhibits dust entering the interior of the housing 21 from the first to fourth openings OP1-OP4 from reaching the drive mechanism. As a result, the inflow of dust into the interior of the cylinder 32 of the drive mechanism in particular can be suppressed, and contamination of the drive mechanism by dust can be suppressed. The maintenance cycle of a driving machine can thus be extended, in turn making it possible to improve the convenience of the driving machine.

Description

Work equipment

[0001] The present invention relates to a work machine that ejects a fastener from an ejection unit.

[0002] An example of a work machine that ejects a fastener from an ejection unit is described in Patent Document 1. The driving machine (work machine) described in Patent Document 1 has a pressure chamber filled with gas, a piston that moves inside a cylinder to increase the pressure in the pressure chamber, a driver blade that is integral with the piston and has a protrusion, a pinwheel that has a pinion pin that can engage with the protrusion, and an electric motor that rotates the pinwheel.

[0003] When the electric motor is driven to move the piston, the pressure in the pressure chamber increases, and then the pinion pin disengages from the protrusion, causing the driver blade to move with force due to the increased pressure in the pressure chamber. As a result, the nail (fastener) supported by the ejection section is struck by the driver blade, and the nail is ejected from the ejection section.

[0004] JP 2018-034267 A

[0005] In the technology described in Patent Document 1, when the piston moves to one side inside the cylinder and the pressure in the pressure chamber increases, air flows into the other side inside the cylinder. Specifically, air containing dust near the opening of the ejection section from which the fastener is ejected flows into the other side inside the cylinder. This causes dust to accumulate inside the cylinder. Therefore, to ensure normal operation of the work machine, it is necessary to frequently remove the dust that has entered the cylinder, which reduces convenience.

[0006] An object of the present invention is to improve the convenience of a work machine.

[0007] In one aspect of the present invention, the device comprises an ejection section that supports a stopper, an actuation section that applies an impact force to the stopper supported by the ejection section, a housing that houses at least a portion of the ejection section and the actuation section and has an opening, and a labyrinth mechanism that is provided in the housing and prevents dust that has entered the housing through the opening from reaching the actuation section.

[0008] According to the present invention, the convenience of the work machine can be improved.

[0009] 17 is a side view showing the appearance of a driving tool according to a first embodiment. It is a diagram showing the internal structure of the driving tool of FIG. 1. It is a cross-sectional view taken along line A-A in FIG. 1. It is a perspective view showing the inside of the first housing half. It is a perspective view showing the inside of the second housing half. It is a partially enlarged perspective view as viewed from the direction of arrow B in FIG. 2. It is a partially enlarged perspective view showing the movement path of air and dust inside the first housing half. It is a partially enlarged perspective view showing the movement path of dust inside the second housing half. It is a partially enlarged cross-sectional view corresponding to FIG. 3, showing only the first and second housing halves, the reducer case, and the cylinder. It is a perspective view showing the outside of the second housing half of the second embodiment. It is a partially enlarged perspective view showing the inside of the second housing half of the second embodiment. It is a perspective view showing the appearance of a driving tool according to a third embodiment. It is a diagram showing the internal structure of a driving tool according to a third embodiment. It is a partially enlarged view showing the movement path of air inside the housing of the third embodiment. It is a diagram showing the internal structure of a driving tool according to a fourth embodiment. It is a cross-sectional view taken along line C-C in FIG. 15. It is a perspective view of the driving tool as viewed from the front, showing the lever holder and the cover separated. It is a perspective view of the driving tool as viewed from the rear, as shown in FIG. 17. Fig. 1 is a perspective view illustrating a housing-side entry portion provided on the lever holder; Fig. 2 is a perspective view illustrating a cover-side entry portion provided on the cover; Fig. 3 is a perspective view of the cover alone, showing the inside of the cover; Fig. 4 is a view of the driving tool from below, showing whether or not the housing is present.

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0011] <Embodiment 1> Figure 1 is a side view showing the appearance of a driving tool of embodiment 1. Figure 2 is a diagram showing the internal structure of the driving tool of Figure 1. Figure 3 is a cross-sectional view taken along line A-A in Figure 1. Figure 4 is a perspective view showing the inside of the first housing half. Figure 5 is a perspective view showing the inside of the second housing half.

[0012] Fig. 6 is a partially enlarged perspective view seen from the direction of arrow B in Fig. 2. Fig. 7 is a partially enlarged perspective view showing the movement paths of air and dust inside the first housing half. Fig. 8 is a partially enlarged perspective view showing the movement paths of dust inside the second housing half. Fig. 9 is a partially enlarged cross-sectional view corresponding to Fig. 3, showing only the first and second housing halves, the reducer case, and the cylinder.

[0013] 1 to 3, a nail driving machine 10 is an electric power tool that shoots nails 11, and is also called a "nail driving machine." The nail driving machine 10 corresponds to the working machine in the present invention. The nail 11 corresponds to the fastener in the present invention.

[0014] The nail driving machine 10 includes a driving machine body 20 and a magazine 60. A plurality of nails 11 are loaded inside the magazine 60, and the nails 11 loaded in the magazine 60 are supplied to the driving machine body 20. In other words, the magazine 60 has the function of supplying the nails 11 to the driving machine body 20. As a result, the nails 11 are driven one by one into a mating material W such as wood by the operation of the driving machine body 20.

[0015] The driving tool body 20 includes a housing 21 formed into a generally annular shape by injection molding a resin material such as plastic. The generally annular shape of the housing 21 allows the operator to hold the housing 21 in a well-balanced manner. This also increases the overall rigidity of the housing 21.

[0016] The housing 21 is hollow and is formed by splitting two halves, a first housing half 22 and a second housing half 23 (see FIGS. 4 and 5), and butting them together.

[0017] 1, the housing 21 is formed of a total of four sections. Specifically, the housing 21 includes a main body housing section 24, a handle section 25, a motor housing section 26, and a battery pack mounting section 27.

[0018] The main body housing 24 extends in the front-to-rear direction. The handle 25 extends downward in a vertical direction intersecting the front-to-rear direction from approximately the center of the main body housing 24 in the longitudinal direction. The motor housing 26 is disposed forward of and spaced apart from the handle 25, and extends downward in the vertical direction from the front of the main body housing 24. The battery pack attachment portion 27 is disposed below and spaced apart from the main body housing 24, and connects the handle 25 and the motor housing 26.

[0019] The "front-rear direction" in which the main body housing portion 24 extends corresponds to the first direction in the present invention. Specifically, the direction in which the nails 11 are ejected is the forward direction. The "up-down direction" in which the handle portion 25 and the motor housing portion 26 extend corresponds to the second direction in the present invention. Specifically, the magazine 60, which is disposed in front of the motor housing portion 26, extends in the up-down direction. Furthermore, the "left-right direction" that is perpendicular to both the "front-rear direction" and the "up-down direction" corresponds to the third direction in the present invention. Specifically, the direction in which the first housing half 22 and the second housing half 23 butt together is the left-right direction.

[0020] As shown in FIG. 1, the main body housing portion 24, the handle portion 25, the motor housing portion 26, and the battery pack attachment portion 27 are connected to form a ring, thereby forming a hollow portion 28 in the approximate center of the housing 21 in which the operator's fingers (not shown) can be placed.

[0021] 2 and 3, a drive mechanism 30 is housed inside the main body housing portion 24. The drive mechanism 30 is driven by a brushless motor 40 housed inside the motor housing portion 26, and generates power to eject the nail 11 toward the mating material W located in front. In other words, the drive mechanism 30 has the function of applying an impact force to the nail 11 supported by the ejection portion 34.

[0022] In this manner, the housing 21 supports the drive mechanism 30 and the brushless motor 40. The rear side of the drive mechanism 30 (cylinder 32) protrudes outside the housing 21 and is covered with a cover member CV. The drive mechanism 30 corresponds to the operating unit in this invention. The brushless motor 40 corresponds to the motor in this invention.

[0023] <Drive Mechanism> As shown in Figures 2 and 3, the drive mechanism 30 includes a nose 31, a cylinder 32, and a pressure accumulator vessel 33. The nose 31 is made of metal and is formed in a stepped, generally cylindrical shape. The nose 31 is disposed on the front side of the main housing portion 24 and has a nose main body portion 31a to which the front end of the cylinder 32 is fixed. The rear side of the injection portion 34 that supports the nail 11 is attached to the front side of the nose 31.

[0024] A rubber bumper (buffer member) 31b formed in a substantially cylindrical shape is housed inside the nose main body 31a. A piston 35a, which is movably mounted inside the cylinder 32, collides with the bumper 31b when it moves from top dead center (rear) to bottom dead center (forward). Specifically, the bumper 31b elastically deforms upon collision with the piston 35a, absorbing the kinetic energy of the piston 35a. This reduces the impact transmitted to the operator. Here, the piston 35a, which is movable inside the cylinder 32 in the axial direction of the cylinder 32, also forms the drive mechanism 30.

[0025] A driver blade 35b formed in a generally rod shape and extending in the front-to-rear direction is movably provided inside the injection section 34. The rear side of the driver blade 35b is fixed to the front side of the piston 35a, and the front side of the driver blade 35b can protrude from the front side of the injection section 34 when the piston 35a moves to the bottom dead center. This drives the nail 11 into the mating material W (see FIG. 1). The driver blade 35b corresponds to the blade in this invention.

[0026] Here, the injection part 34 protrudes in the axial direction from the housing 21. Specifically, the front side of the injection part 34 protrudes outside the housing 21. This allows the position of the injection part 34 to be easily visually observed by an operator. The driver blade 35b, which extends from the piston 35a in the axial direction of the cylinder 32, is formed in a rod shape, and moves in the axial direction of the cylinder 32 to strike the nail 11, also forms the drive mechanism 30.

[0027] A pinwheel 36 that moves the driver blade 35b rearward is rotatably housed inside the nose body 31a. The pinwheel 36 is provided with a plurality of pins 36a, which are engageable with a plurality of racks (protrusions) 35c that are integrally formed on the driver blade 35b.

[0028] The pinwheel 36 is rotated by a brushless motor 40 and has the function of moving the piston 35 a including the driver blade 35 b rearward against the pressing force of the pressure chamber 33 a of the pressure accumulator vessel 33 .

[0029] The pressure accumulator container 33 is connected to the rear end of the cylinder 32. Specifically, the pressure accumulator container 33 seals the rear side of the cylinder 32. The pressure accumulator container 33 is covered and protected by a cover member CV. A pressure chamber 33a is formed inside the pressure accumulator container 33, and the pressure chamber 33a is filled with gas at a pressure higher than atmospheric pressure. The gas filled inside the pressure chamber 33a is, for example, pressurized air or an inert gas (nitrogen gas, etc.).

[0030] As a result, the piston 35a (driver blade 35b), which is movably provided inside the cylinder 32, can move vigorously from the top dead center toward the bottom dead center due to the pressure in the pressure chamber 33a. In other words, the pressure accumulator container 33 generates a pressing force that moves the piston 35a forward, and as a result, the driver blade 35b integrated with the piston 35a strikes the nail 11 supported by the ejection part 34.

[0031] The piston 35a is formed in a cylindrical shape with a bottom, and the outer diameter of the piston 35a is slightly smaller than the inner diameter of the cylinder 32. A seal member 35d is attached to the outer periphery of the piston 35a, thereby sealing the gap between the pressure chamber 33a side of the piston 35a and the bumper 31b side.

[0032] A plurality of through holes 32a are provided on the front side of the cylinder 32, and these through holes 32a connect the inside and outside of the cylinder 32. Air circulating inside the housing 21 flows into the inside of the cylinder 32 via these through holes 32a. Specifically, as the piston 35a including the driver blade 35b moves rearward, air flows into the inside of the cylinder 32 via the through holes 32a. The through holes 32a correspond to the inlet holes in this invention.

[0033] A cylindrical push lever 37 is provided in front of the ejection unit 34. Specifically, the push lever 37 can be moved rearward relative to the ejection unit 34 by hitting the target material W (see FIG. 1). The driving tool 10 can be operated only when the push lever 37 is moved rearward relative to the ejection unit 34.

[0034] <Peripheral Structure of Brushless Motor> As shown in Figure 2, a brushless motor 40 is housed inside the motor housing portion 26. The brushless motor 40 is formed in a substantially cylindrical shape and includes a stator 41 disposed radially outward, and a rotor 42 rotatably disposed radially inward of the stator 41. A rotating shaft 42a extending in the vertical direction is fixed to the center of rotation of the rotor 42.

[0035] A controller 43 is electrically connected to the brushless motor 40, and is disposed inside the housing 21 between the brushless motor 40 and the battery pack 50. Specifically, the controller 43 is provided inside the battery pack mounting portion 27 to which the battery pack 50 is attached. In addition to the brushless motor 40, the controller 43 is electrically connected to a limit switch 44a operated by a trigger switch 44, a sensor (not shown) that detects the movement of the battery pack 50 and the push lever 37, and the like.

[0036] The trigger switch 44 and the limit switch 44a are provided on the handle portion 25. The trigger switch 44 can be moved rearward when pressed by the operator. As a result, the limit switch 44a is turned on as the trigger switch 44 moves rearward. The controller 43 supplies a drive current from the battery pack 50 to the brushless motor 40 based on the rearward movement of the push lever 37 and the ON state of the limit switch 44a (AND condition).

[0037] Furthermore, a planetary gear reducer 45 is provided inside the motor housing portion 26 on the side (upper side) where the pinwheel 36 of the brushless motor 40 is provided. That is, the brushless motor 40, planetary gear reducer 45, and pinwheel 36 are arranged in this order from bottom to top. The input side (lower side) of the planetary gear reducer 45 is connected to the rotating shaft 42a that forms the brushless motor 40 so as to be able to transmit power. On the other hand, the output side (upper side) of the planetary gear reducer 45 is connected to the pinwheel 36 so as to be able to transmit power.

[0038] Specifically, the planetary gear reducer 45, located between the brushless motor 40 and the pinwheel 36, includes a gear mechanism 45a (not shown in detail) consisting of a sun gear, planetary gears, an internal gear, etc., and a cylindrical case 45b that houses the gear mechanism 45a. The planetary gear reducer 45 reduces the rotational speed of the rotary shaft 42a to a predetermined speed and transmits the high-torque rotational force to the pinwheel 36. This allows even a compact brushless motor 40 to move the piston 35a, including the driver blade 35b, against the pressure inside the pressure chamber 33a. The gear mechanism 45a has the function of transmitting the driving force of the brushless motor 40 to the drive mechanism 30 and corresponds to the transmission mechanism in this invention.

[0039] Here, the pin 36a of the pinwheel 36 is able to engage with the rack 35c of the driver blade 35b when the piston 35a is at the bottom dead center. The piston 35a is moved from the bottom dead center to the top dead center by driving the brushless motor 40. Thereafter, when the piston 35a reaches the top dead center, the engagement between the pin 36a and the rack 35c is released. Therefore, the piston 35a including the driver blade 35b moves vigorously from the top dead center to the bottom dead center due to the increased pressure in the pressure chamber 33a.

[0040] 1 and 2, the magazine 60 includes a magazine case 61 and a feeder 62 movably provided on the magazine case 61. The magazine case 61 is formed in a substantially rectangular parallelepiped shape and extends vertically so as to be parallel to the motor housing portion 26 that forms the housing 21.

[0041] The upper end of the magazine case 61 is connected to the ejection unit 34 (see FIG. 3 ). A plurality of nails 11 are loaded inside the magazine case 61 so as to be aligned in the vertical direction, and these nails 11 are movable in the vertical direction inside the magazine case 61.

[0042] Furthermore, the feeder 62 has a function of supplying the nails 11 loaded in the magazine case 61 one by one to the ejection unit 34. Specifically, the nails 11 are supplied one by one into the ejection unit 34 by the spring force of a biasing spring (not shown) provided in the feeder 62. The nails 11 are supplied into the ejection unit 34 when the piston 35a reaches the top dead center.

[0043] 1 and 2, a battery pack 50 is attached to the battery pack attachment section 27 that forms the housing 21. Specifically, a guide rail (not shown) extending in the front-rear direction is provided between the battery pack attachment section 27 and the battery pack 50, and the battery pack 50 is attached to the battery pack attachment section 27 via the guide rail.

[0044] Then, by attaching the battery pack 50 to the battery pack attachment section 27, a battery-side terminal (not shown) provided on the battery pack 50 and an attachment-section-side terminal (not shown) provided on the battery pack attachment section 27 are electrically connected to each other, thereby enabling the battery pack 50 to supply a driving current to the brushless motor 40.

[0045] The battery pack 50 employs a secondary battery such as a lithium ion battery or a nickel-metal hydride battery.

[0046] 4, 6, and 7, the first housing half 22 forming the housing 21 is located on the left side of the driving tool 10. The first housing half 22 is made of a resin material such as plastic, and a first cylinder accommodating chamber 22a is formed inside and at the rear of the main housing portion 24 forming the first housing half 22 to accommodate the cylinder 32 (see FIGS. 2 and 3) forming the drive mechanism 30.

[0047] A first injection portion accommodating chamber 22b that accommodates the injection portion 34 (see FIG. 3) is formed inside and in front of the main body housing portion 24 that forms the first housing half 22. The volume of the first injection portion accommodating chamber 22b is smaller than the volume of the first cylinder accommodating chamber 22a.

[0048] Furthermore, a first opening OP1 that connects the interior and exterior of the first housing half 22 is formed below the first firing unit accommodating chamber 22b. Specifically, as shown in FIG. 6 , the first opening OP1 is formed at a location on the first housing half 22 where the magazine 60 is inserted. In other words, the first opening OP1 serves as a passage through which the magazine 60 extends from the interior to the exterior of the first housing half 22. When the magazine 60 is connected to the firing unit 34, the first opening OP1 connects the interior and exterior of the first housing half 22, and the magazine 60 and the first housing half 22 do not interfere with each other. Therefore, the magazine 60 can be easily attached to and detached from the firing unit 34.

[0049] A second opening OP2 is formed on the front side of the first injection portion accommodating chamber 22b, connecting the inside and outside of the first housing half 22. Specifically, as shown in Fig. 6, the second opening OP2 is formed at a location where the injection portion 34 of the first housing half 22 is inserted. When the driving tool 10 is assembled, the second opening OP2 connects the inside and outside of the first housing half 22, and the injection portion 34 and the first housing half 22 do not interfere with each other.

[0050] Both the first opening OP1 and the second opening OP2 are arranged in a region overlapping with the drive mechanism 30 in the axial direction of the cylinder 32, which is the direction in which the drive mechanism 30 applies a striking force to the nail 11. This region is close to the injection unit 34, and can also be said to be close to the target material W into which the nail 11 is driven. This region is a region into which dust generated from the target material W when the nail 11 is driven into the target material W can relatively easily enter.

[0051] 4 and 7, a first connection space 22c that connects the first cylinder accommodating chamber 22a and the first injection unit accommodating chamber 22b along the front-rear direction of the main body housing portion 24 is provided between the first cylinder accommodating chamber 22a and the first injection unit accommodating chamber 22b. A labyrinth mechanism 70 that bends the movement path of air flowing from the first injection unit accommodating chamber 22b toward the first cylinder accommodating chamber 22a is disposed in the first connection space 22c. The first connection space 22c is disposed inside and above the motor housing portion 26 that forms the first housing half 22.

[0052] The first injection portion accommodating chamber 22b and the first connection space 22c of the first housing half 22 communicate between the first and second openings OP1, OP2 and the drive mechanism 30, and correspond to the communication passage in the present invention. The first and second openings OP1, OP2 correspond to the opening in the present invention. Furthermore, of the first and second openings OP1, OP2, the first opening OP1 corresponds to the first opening in the present invention. Furthermore, of the first and second openings OP1, OP2, the second opening OP2 corresponds to the second opening in the present invention. Furthermore, the first and second openings OP1, OP2 also correspond to the third opening in the present invention.

[0053] The labyrinth mechanism 70 has a function of preventing dust that has entered the housing 21 through the openings (first to fourth openings OP1 to OP4) thereof from reaching the drive mechanism 30, and includes a first main inclined wall 71, a second main inclined wall 72, and a third main inclined wall 73. Specifically, the labyrinth mechanism 70 is disposed between the openings (first to fourth openings OP1 to OP4) of the housing 21 and the through-hole 32a of the cylinder 32.

[0054] The first to third main inclined walls 71 to 73 that form the labyrinth mechanism 70 are provided in the first connection space portion 22 c and are arranged side by side in the stated order from the upstream side (front side) of the first air passage PS1 that is formed inside the first injection portion accommodating chamber 22 b and the first connection space portion 22 c. The first to third main inclined walls 71 to 73 are integrally provided on the inside of the first housing half 22 and are formed in a generally flat plate shape.

[0055] The first air passage PS1 extends in the front-rear direction and forms part of the interior of the first injection portion accommodating chamber 22b and the first connection space 22c. In this way, the first housing half 22 that forms the housing 21 defines the first air passage PS1, and the first air passage PS1 corresponds to the first passage in the present invention.

[0056] Here, in order to make it easier to understand the arrangement of the first to third main inclined walls 71 to 73 relative to the first housing half 22, the first to third main inclined walls 71 to 73 are shown shaded in FIGS.

[0057] Furthermore, the first to third main inclined walls 71 to 73 each gradually become larger toward the downstream side of the first air passage PS1. Of the first to third main inclined walls 71 to 73, a portion (one end) of the upper side of the second and third main inclined walls 72, 73 is disposed in the first air passage PS1 and extends in a direction intersecting the front-to-rear direction in which the first air passage PS1 extends so as to partially block the first air passage PS1. This makes it easier to capture air that attempts to flow straight from front to rear along the first air passage PS1, thereby bending the flow of air passing through the first air passage PS1.

[0058] In this way, the entire second main inclined wall 72 and the upper side of the third main inclined wall 73 are inclined so as to extend in the front-to-back and up-to-down directions, and one end of each is positioned in the first air passage PS1, which corresponds to the cross wall in this invention.

[0059] The first main inclined wall 71 is also inclined so that its entire length extends in both the front-rear direction and the up-down direction. The first and second main inclined walls 71, 72 are each inclined so that their upper sides are located further upstream of the first air passage PS1 than their lower sides.

[0060] In contrast, only the upper portion of the largest third main inclined wall 73 is inclined in the same manner as the first and second main inclined walls 71 and 72. The lower portion of the third main inclined wall 73 extends straight in the up-down direction. In this way, only the third main inclined wall 73 has a different shape from the first and second main inclined walls 71 and 72, and is substantially V-shaped when viewed from the left-right direction.

[0061] Furthermore, the labyrinth mechanism 70 provided in the first connection space portion 22c includes a sub-inclined wall 74. The sub-inclined wall 74 is integrally provided on the upper side of the third main inclined wall 73 and has a protruding height that is lower than the protruding heights of the first to third main inclined walls 71 to 73. This allows a portion of the nose 31 to be disposed inside the first connection space portion 22c (see FIG. 3).

[0062] Like the first and second main inclined walls 71 and 72, the sub-inclined wall 74 is inclined so that its upper side is positioned upstream of the first air passage PS1 relative to its lower side, and has the function of bending the air flowing from front to rear along the first air passage PS1.

[0063] Furthermore, inside the motor housing portion 26 that forms the first housing half 22, and in front of the side (upper side) where the first connection space portion 22c is located, a first dust storage chamber 26a is located adjacent to the lower side (other end) of the third main inclined wall 73. That is, the first housing half 22 defines the first dust storage chamber 26a. The first dust storage chamber 26a serves as a portion where dust (not shown) contained in the air bent by the labyrinth mechanism 70 is temporarily stored. The first dust storage chamber 26a corresponds to the dust storage chamber in this invention.

[0064] Furthermore, the first housing half 22 is provided with a first exhaust port 26b adjacent to the first dust storage chamber 26a. The first exhaust port 26b connects the first dust storage chamber 26a to the outside of the first housing half 22. As a result, the dust accumulated in the first dust storage chamber 26a is discharged to the outside of the first housing half 22 (housing 21) due to vibrations generated during operation of the driving tool 10 and air flow inside the first housing half 22. The first exhaust port 26b corresponds to the exhaust port in this invention.

[0065] Specifically, the air flowing from the front to the rear along the first air passage PS1 contains dust, but because the dust is heavier than air, it falls below after colliding with the first to third main inclined walls 71 to 73 and the sub-inclined wall 74. This allows the dust to be temporarily stored in the first dust storage chamber 26a.

[0066] A first guide wall 26c is provided between the lower end of the third main inclined wall 73 and the first discharge port 26b. The first guide wall 26c guides dust that has fallen downward through the first dust storage chamber 26a to the first discharge port 26b. The inclination direction of the first guide wall 26c is opposite to the inclination direction of the sub-inclined wall 74. That is, the first guide wall 26c is inclined so that the upper side of the first guide wall 26c is located further downstream in the first air passage PS1 than the lower side of the first guide wall 26c. The first guide wall 26c corresponds to the guide wall in this invention.

[0067] First guide wall 26c is provided integrally with first housing half 22, and like sub-inclined wall 74, has a low protruding height. This allows first guide wall 26c to be disposed to the side of cylindrical case 45b of planetary gear reducer 45. Furthermore, first dust collection chamber 26a is surrounded by first bottom wall portion 26d and first top wall portion 26e, which makes it difficult for dust that reaches and temporarily accumulates in first dust collection chamber 26a to scatter to other parts of first housing half 22.

[0068] Here, first guide wall 26c and first dust storage chamber 26a are each disposed to the side of cylindrical case 45b of planetary gear reducer 45. This makes it difficult for dust to reach first brushless motor storage portion 26f of first housing half 22, which stores brushless motor 40. This prevents brushless motor 40 from being soiled by dust.

[0069] 2, brushless motor 40 includes centrifugal fan 42b fixed to rotating shaft 42a. When brushless motor 40 is running, it draws in outside air through a plurality of first air intake holes 26g (see FIG. 1) provided in first housing half 22. The air (hot air) that has absorbed heat by passing through stator 41 is then discharged to the outside through a plurality of first exhaust holes 26h (see FIG. 1) provided in first housing half 22.

[0070] Here, the multiple first air intake holes 26g are arranged in an area that does not overlap with the drive mechanism 30 in the axial direction of the cylinder 32, and are arranged in a location away from the ejection part 34 (the material W into which the nail 11 is driven) where dust is likely to be generated. Therefore, almost no dust is sucked into the inside of the first housing half 22 through the multiple first air intake holes 26g.

[0071] 5, 6, and 8, the second housing half 23 that forms the housing 21 is located on the right side of the driver 10. The second housing half 23 is made of a resin material such as plastic, and a second cylinder accommodating chamber 23a that accommodates the cylinder 32 (see FIGS. 2 and 3) that forms the drive mechanism 30 is formed inside and at the rear of the main housing portion 24 that forms the second housing half 23.

[0072] Furthermore, a second injection portion accommodating chamber 23b that accommodates the injection portion 34 (see FIG. 3) is formed inside and on the front side of the main body housing portion 24 that forms the second housing half 23. Here, the volume of the second injection portion accommodating chamber 23b is smaller than the volume of the second cylinder accommodating chamber 23a.

[0073] Furthermore, a third opening OP3 that connects the inside and outside of the second housing half 23 is formed below the second ejection unit accommodating chamber 23b. Specifically, as shown in FIG. 6 , the third opening OP3 is formed at a location in the second housing half 23 where the magazine 60 is inserted. In other words, the third opening OP3 serves as a passage through which the magazine 60 extends from the inside to the outside of the second housing half 23. When the magazine 60 is connected to the ejection unit 34, the third opening OP3 connects the inside and outside of the second housing half 23, and the magazine 60 and the second housing half 23 do not interfere with each other.

[0074] A fourth opening OP4 is formed on the front side of the second injection portion accommodating chamber 23b, connecting the inside and outside of the second housing half 23. Specifically, as shown in Fig. 6, the fourth opening OP4 is formed at a location where the injection portion 34 of the second housing half 23 is inserted. When the driving tool 10 is assembled, the fourth opening OP4 connects the inside and outside of the second housing half 23, and the injection portion 34 and the second housing half 23 do not interfere with each other.

[0075] 5 and 8, a second connection space 23c is provided between the second cylinder accommodating chamber 23a and the second injection chamber accommodating chamber 23b along the front-rear direction of the main body housing portion 24, connecting the respective accommodating chambers 23a, 23b. The pinwheel 36 (see FIG. 3) housed in the nose main body portion 31a is disposed in the second connection space 23c. That is, in the left-right direction of the housing 21, the first to third main inclined walls 71-73 and the sub-inclined wall 74 are disposed on the left side, and the pinwheel 36 is disposed on the right side. The second connection space 23c is disposed inside and above the motor housing portion 26 that forms the second housing half 23.

[0076] The second injection section accommodating chamber 23b and the second connection space 23c of the second housing half 23 communicate between the third and fourth openings OP3 and OP4 and the drive mechanism 30, and correspond to the communication passage in the present invention. The third and fourth openings OP3 and OP4 correspond to the opening in the present invention. Of the third and fourth openings OP3 and OP4, the third opening OP3 corresponds to the first opening in the present invention. Of the third and fourth openings OP3 and OP4, the fourth opening OP4 corresponds to the second opening in the present invention. The third and fourth openings OP3 and OP4 also correspond to the third opening in the present invention.

[0077] Here, the first air passage PS1 (see FIG. 7) forms part of the interior of the second injection portion accommodating chamber 23b and the second connection space portion 23c. In other words, the first air passage PS1 is also defined in the second housing half 23 that forms the housing 21.

[0078] Furthermore, a second dust collection chamber 26k is disposed inside the motor housing portion 26 that forms the second housing half 23, in front of the side (upper side) where the second connection space portion 23c is disposed, adjacent to the lower side (other end) of the third main inclined wall 73. That is, the second housing half 23 defines the second dust collection chamber 26k. The second dust collection chamber 26k is a portion where dust contained in the air bent by the labyrinth mechanism 70 (see FIG. 7) is temporarily stored. The second dust collection chamber 26k corresponds to the dust collection chamber in this invention.

[0079] The second housing half 23 is also provided with a second exhaust port 26m adjacent to the second dust storage chamber 26k. The second exhaust port 26m connects the second dust storage chamber 26k to the outside of the second housing half 23. As a result, the dust accumulated in the second dust storage chamber 26k is discharged to the outside of the second housing half 23 (housing 21) due to vibrations generated during operation of the driving tool 10 and air flow inside the second housing half 23. The second exhaust port 26m corresponds to the exhaust port in this invention.

[0080] Specifically, dust contained in the air flowing from the front to the rear along the first air passage PS1 (see FIG. 7) passes through the labyrinth mechanism 70 provided in the first housing half 22 and goes around the side of the cylindrical case 45b of the planetary gear reducer 45. As a result, the dust reaches the second dust storage chamber 26k.

[0081] A second guide wall 26n is provided between the lower end of the third main inclined wall 73 and the second discharge port 26m to guide dust that has fallen downward through the second dust storage chamber 26k to the second discharge port 26m. Similar to the first guide wall 26c of the first housing half 22 (see FIG. 7), the second guide wall 26n is inclined so that the upper side of the second guide wall 26n is located further downstream in the first air passage PS1 than the lower side of the second guide wall 26n. The second guide wall 26n corresponds to the guide wall in this invention.

[0082] In this way, the first guide wall 26c and the second guide wall 26n disposed on the sides of the cylindrical case 45b also extend in the left-right direction so as to wrap around the sides of the cylindrical case 45b. Air drawn into the housing 21 flows along these first and second guide walls 26c, 26n.

[0083] That is, the first and second guide walls 26c, 26n provided in the housing 21 (first and second housing halves 22, 23) define a second air passage PS2 extending in the left-right direction, as shown in Figure 9, and the second air passage PS2 forming part of the interior of the first and second connection space portions 22c, 23c corresponds to the second passage in the present invention.

[0084] In addition, the cylindrical case 45b has the function of bending the air flowing along the second air passage PS2 so that it follows the side of the cylindrical case 45b, and the cylindrical case 45b forms part of the labyrinth mechanism 70.

[0085] Furthermore, like the first guide wall 26c, the second guide wall 26n also has a reduced protruding height, which allows the second guide wall 26n to be disposed to the side of the cylindrical case 45b of the planetary gear reducer 45. Furthermore, the second dust collection chamber 26k is surrounded by the second bottom wall portion 26p and the second top wall portion 26q, which makes it difficult for dust that reaches and is temporarily stored in the second dust collection chamber 26k to scatter to other parts of the second housing half 23.

[0086] Here, second guide wall 26n and second dust storage chamber 26k are also disposed to the side of cylindrical case 45b of planetary gear reducer 45. This makes it difficult for dust to reach first brushless motor storage portion 26r of second housing half 23, which stores brushless motor 40. This prevents brushless motor 40 from being soiled by dust.

[0087] 2, second housing half 23 is also provided with a plurality of second intake holes 26s and second exhaust holes 26t, which also improves the cooling efficiency of brushless motor 40. In the left-right direction of housing 21, second intake holes 26s face first intake holes 26g, and second exhaust holes 26t face first exhaust holes 26h.

[0088] <Air Flow Inside the Housing> Next, the operation of the driving tool 10 configured as described above, particularly the air flow inside the housing 21, will be described in detail with reference to the drawings.

[0089] 1, the push lever 37 of the driving tool 10 is brought into contact with the workpiece W, the push lever 37 is moved rearward as indicated by arrow M1, and the trigger switch 44 is pulled in as indicated by arrow M2. This drives the brushless motor 40, causing the pinwheel 36 to rotate via the planetary gear reducer 45. This causes the piston 35a to move rearward against the pressure in the pressure chamber 33a, increasing the pressure in the pressure chamber 33a.

[0090] At this time, as the piston 35a moves rearward, a negative pressure is created in the area in front of the piston 35a (on the bumper 31b side of the cylinder 32), causing air inside the housing 21 to flow into the interior and front side of the cylinder 32 through the multiple through-holes 32a.

[0091] 6, air flows into the housing 21 (first and second housing halves 22 and 23) from the first and third openings OP1 and OP3, which are relatively large openings on the front side of the driving tool 10, as shown by air flow FL1. Air also flows into the housing 21 from the second and fourth openings OP2 and OP4, which are relatively small openings on the front side of the driving tool 10, as shown by air flow FL2.

[0092] Here, the first to fourth openings OP1 to OP4 are all positioned in an area that overlaps with the drive mechanism 30 in the axial direction of the cylinder 32 and are positioned near the target material W (positioned on the front side of the driving tool 10), so the respective air flows FL1, FL2 contain a relatively large amount of dust. As shown in Figures 7 and 9, the dust-containing air flows into the first and second injection chambers 22b, 23b of the first and second housing halves 22, 23 and flows from front to rear along the first air passage PS1.

[0093] Thereafter, the air flowing along the first air passage PS1 flows into the first and second connection spaces 22c, 23c located rearward of the first and second injection chamber housing chambers 22b, 23b, and most of the air flows toward the labyrinth mechanism 70 of the first housing half 22, as shown by air flows FL3, FL4, FL5, FL6 in Fig. 9. This is because the cylindrical case 45b of the planetary gear reducer 45 is disposed in the second connection space 23c, which prevents air movement.

[0094] 7 , the airflow FL3 of the airflows FL3, FL4, FL5, and FL6 flows along the first main inclined wall 71 of the labyrinth mechanism 70 and is bent so that its destination faces downward. The airflow FL4 of the airflows FL3, FL4, FL5, and FL6 flows along the second main inclined wall 72 of the labyrinth mechanism 70 and is bent so that its destination faces downward. The airflow FL5 of the airflows FL3, FL4, FL5, and FL6 flows along the sub-inclined wall 74 and the third main inclined wall 73 and is bent so that its destination faces downward. In this way, the first to third main inclined walls 71 to 73 and the sub-inclined wall 74 bend the airflow (airflows FL3, FL4, and FL5) flowing along the first air passage PS1.

[0095] Of the air flows FL3, FL4, FL5, and FL6, the air flow FL6 flows substantially straight from the front to the rear along the first air passage PS1 and flows directly into the interior of the cylinder 32 through the through-hole 32a. Of course, the air flow FL6 also contains a small amount of dust, but most of the other air flows FL3 to FL5 collide with the first to third main inclined walls 71 to 73 and the sub-inclined wall 74.

[0096] Therefore, most of the dust contained in the air flows FL1 and FL2 that have flowed into the housing 21 falls below the labyrinth mechanism 70. This prevents the inside of the cylinder 32 from being soiled.

[0097] The air flows FL3 to FL5 bent by the first to third main inclined walls 71 to 73 and the sub-inclined wall 74 of the labyrinth mechanism 70 are directed toward the side of the cylindrical case 45b of the planetary gear reducer 45, as shown in FIG. 9. The air flows FL3 to FL5 directed toward the side of the cylindrical case 45b are then divided into the second air passage PS2 on the side where the first guide wall 26c is located and the second air passage PS2 on the side where the second guide wall 26n is located. As a result, the dust contained in the air flows FL3 to FL5 is divided into that which falls onto the first guide wall 26c and that which falls onto the second guide wall 26n.

[0098] The dust that has fallen onto the first guide wall 26c is then moved toward the first dust storage chamber 26a, as shown by arrow M3 in Fig. 7. Then, as the driving tool 10 vibrates or its posture changes, the dust that has accumulated in the first dust storage chamber 26a is discharged to the outside of the housing 21 through the first discharge port 26b due to its own weight (or due to the air flow inside the housing 21), as shown by arrow M4 in Fig. 7.

[0099] Meanwhile, the dust that has fallen onto the second guide wall 26n moves toward the second dust storage chamber 26k as shown by arrow M5 in Fig. 8. Then, as the driving tool 10 vibrates or its posture changes, the dust that has accumulated in the second dust storage chamber 26k is discharged to the outside of the housing 21 through the second discharge port 26m due to its own weight (or due to the air flow inside the housing 21) as shown by arrow M6 in Fig. 8.

[0100] In this way, the dust contained in the air flows FL3 to FL5 bent by the first to third main inclined walls 71 to 73 and the sub-inclined wall 74 travels through the second air passage PS2 on the side where the first guide wall 26c is disposed and the second air passage PS2 on the side where the second guide wall 26n is disposed, and reaches the first dust storage chamber 26a and the second dust storage chamber 26k (see FIG. 9). Therefore, the amount of dust that enters the interior of the cylinder 32 through the multiple through-holes 32a can be reduced accordingly.

[0101] 3, when the piston 35a reaches the top dead center due to the rotation of the pinwheel 36, the engagement between the pin 36a and the rack 35c is released. Therefore, the piston 35a including the driver blade 35b moves vigorously from the top dead center to the bottom dead center due to the increased pressure in the pressure chamber 33a. As a result, the nail 11 supported by the ejection part 34 is struck from behind and ejected from the ejection part 34 and the push lever 37 toward the target material W as shown by arrow M7 in FIG. 1, and the nail 11 is driven into the target material W.

[0102] As described above in detail, according to the first embodiment, the tool includes the ejection unit 34 that supports the nail 11, the drive mechanism 30 that applies an impact force to the nail 11 supported by the ejection unit 34, the housing 21 that houses at least a part of the ejection unit 34 and the drive mechanism 30 and has first to fourth openings OP1 to OP4, and the labyrinth mechanism 70 that is provided in the housing 21 and prevents dust that has entered the housing 21 through the first to fourth openings OP1 to OP4 from reaching the drive mechanism 30.

[0103] This prevents dust from entering the drive mechanism 30, particularly the cylinder 32, and prevents the drive mechanism 30 from being contaminated by dust. This makes it possible to extend the maintenance cycle of the driving tool 10, thereby improving the convenience of the driving tool 10.

[0104] Furthermore, according to the first embodiment, the labyrinth mechanism 70 is provided in the first and second connection spaces 22c, 23c which connect the first to fourth openings OP1 to OP4 with the drive mechanism 30, and bends the flow of air passing through the first and second injection portion accommodating chambers 22b, 23b and the first and second connection spaces 22c, 23c (first air passage PS1).

[0105] This applies centrifugal force to the air flow inside the housing 21, and the difference in weight (difference in specific gravity) between the air and the dust can be used to effectively separate the two.

[0106] Furthermore, according to the first embodiment, the housing 21 defines a first air passage PS1 that is part of the first and second injection portion accommodating chambers 22b, 23b and the first and second connection space portions 22c, 23c and extends in the front-to-rear direction, and the labyrinth mechanism 70 includes second and third main inclined walls 72, 73 that extend in the up-down direction intersecting the front-to-rear direction and have one end located in the first air passage PS1 to bend the flow of air flowing through the first air passage PS1.

[0107] This allows the direction of the dust-laden air to be changed from a front-to-back direction to an up-to-down direction, making it possible to effectively drop the dust, which is heavier than air, downwards.

[0108] Furthermore, according to embodiment 1, the housing 21 is disposed adjacent to the other end of the third main inclined wall 73 and defines the first and second dust storage chambers 26a, 26k for storing dust contained in the air.

[0109] This allows dust contained in the air to be stored in the first and second dust storage chambers 26a and 26k, thereby preventing dust from reaching the brushless motor 40, the controller 43, and other components that are sensitive to dust.

[0110] Furthermore, according to the first embodiment, the housing 21 has the first and second exhaust ports 26b, 26m that connect the first and second dust storage chambers 26a, 26k to the outside of the housing 21.

[0111] This allows the dust that has reached the first and second dust storage chambers 26a and 26k to be discharged from the first and second outlets 26b and 26m to the outside of the housing 21. This prevents the inside of the housing 21 from being soiled with dust, which also makes it possible to extend the maintenance cycle of the driving tool 10.

[0112] Furthermore, according to embodiment 1, the housing 21 is provided with first and second guide walls 26c, 26n that are arranged between the other end of the third main inclined wall 73 and the first and second exhaust outlets 26b, 26m and guide dust to the first and second exhaust outlets 26b, 26m.

[0113] This makes it easier for dust to accumulate in the first and second dust storage chambers 26a, 26k, and also makes it possible to quickly discharge the dust to the outside of the housing 21 through the first and second discharge ports 26b, 26m.

[0114] Furthermore, according to the first embodiment, the entire second main inclined wall 72 and the upper side of the third main inclined wall 73 are inclined so as to extend in both the front-rear direction and the up-down direction.

[0115] This allows the flow of air circulating inside the housing 21 to bend gently, making it possible to smooth the flow of air inside the housing 21 (reducing flow resistance).

[0116] Furthermore, according to the first embodiment, the housing 21 defines a second air passage PS2 that is part of the first and second connection spaces 22c, 23c and extends in the left-right direction, and inside the housing 21 are provided a brushless motor 40 and a cylindrical case 45b that houses a gear mechanism 45a that transmits the driving force of the brushless motor 40 to the drive mechanism 30, and the labyrinth mechanism 70 is formed by the cylindrical case 45b and bends the air flowing through the second air passage PS2.

[0117] This allows the cylindrical case 45b, which is one of the components that form the driving tool 10, to be used as the labyrinth mechanism 70. Therefore, there is no need to provide a separate part for the labyrinth mechanism 70, and it is possible to avoid making the structure of the housing 21 more complex and the overall size of the driving tool 10 larger.

[0118] Furthermore, according to the first embodiment, the drive mechanism 30 includes a cylinder 32, a piston 35a that is movable inside the cylinder 32 in the axial direction of the cylinder 32, and a rod-shaped driver blade 35b that extends axially from the piston 35a and strikes the nail 11 by moving in the axial direction of the cylinder 32, and the cylinder 32 has a through hole 32a through which air flows in as the piston 35a moves, and the labyrinth mechanism 70 is disposed between the first to fourth openings OP1 to OP4 and the through hole 32a.

[0119] This prevents dust from entering the cylinder 32 even when the housing 21 is used in a manner that allows air containing a large amount of dust to enter the housing 21 through the first to fourth openings OP1 to OP4. This effectively prevents the gas filled in the pressure chamber 33a from leaking, thereby reducing the impact force.

[0120] Furthermore, according to the first embodiment, a magazine 60 that supplies nails 11 is connected to the ejection section 34, and the first to fourth openings OP1 to OP4 include the first and third openings OP1 and OP3 that serve as passages through which the magazine 60 extends from the inside to the outside of the housing 21.

[0121] As a result, even if the first and third openings OP1, OP3 are located at a location where the magazine 60 is placed, where dust is likely to flow in, the labyrinth mechanism 70 effectively prevents dust from flowing into the inside of the cylinder 32.

[0122] Furthermore, according to embodiment 1, the injection portion 34 protrudes in the axial direction from the inside to the outside of the housing 21, and the first to fourth openings OP1 to OP4 include second and fourth openings OP2, OP4 which serve as passages through which the injection portion 34 extends from the inside to the outside of the housing 21.

[0123] As a result, even if the second and fourth openings OP2 and OP4 are located at the location of the injection section 34, where dust is likely to flow in, the labyrinth mechanism 70 effectively prevents dust from flowing into the inside of the cylinder 32.

[0124] <Embodiment 2> Next, embodiment 2 of the present invention will be described in detail with reference to the drawings. Note that parts having the same functions as those in embodiment 1 described above will be given the same reference numerals and detailed description thereof will be omitted.

[0125] Fig. 10 is a perspective view showing the outside of the second housing half of the second embodiment. Fig. 11 is a partially enlarged perspective view showing the inside of the second housing half of the second embodiment.

[0126] 10 and 11 , the second embodiment differs from the first embodiment only in the shape of the second housing half 80. Specifically, the second housing half 80 is provided with a labyrinth-shaped communication port 81 that connects the second connection space portion 23c with the outside of the second housing half 80.

[0127] Three labyrinth-shaped communication ports 81 are arranged in a line in the vertical direction on the upper side of the motor housing portion 26. Each of these labyrinth-shaped communication ports 81 has a hole 81a that opens in both the front-rear direction and the left-right direction, and an opposing wall 81b that faces the hole 81a in both the front-rear direction and the left-right direction.

[0128] As a result, when the interior of the housing 21 becomes negative pressure, that is, when the piston 35a (see FIG. 3) moves rearward inside the cylinder 32 (see FIG. 3), air flows from the outside to the inside of the second housing half 80, as shown by the airflow FL7 in FIGS. 10 and 11 . At this time, the air that passes through the hole 81a is bent by the opposing wall 81b. This prevents dust contained in the airflow FL7 from entering the interior of the second housing half 80.

[0129] The three labyrinth-shaped communication ports 81 do not contain a large amount of dust because they are located away from the injection section 34. Furthermore, the dust contained in the airflow FL7 collides with the labyrinth mechanism 70 inside the cylinder 32, making it difficult for the dust to reach the cylinder 32.

[0130] The second embodiment configured as described above can also achieve the same effects as the first embodiment. In addition, in the second embodiment, air also flows into the interior of the cylinder 32 from a total of three labyrinth-shaped communication ports 81. This reduces the amount of air flowing into the interior of the cylinder 32 from the first to fourth openings OP1 to OP4 (see FIG. 6). This further reduces dust contamination of the drive mechanism 30 (see FIG. 3), further extending the maintenance cycle of the driving tool 10.

[0131] <Embodiment 3> Next, embodiment 3 of the present invention will be described in detail with reference to the drawings. Note that parts having the same functions as those in embodiment 2 described above will be given the same reference numerals and detailed description thereof will be omitted.

[0132] Figure 12 is a perspective view showing the appearance of a driving tool according to embodiment 3. Figure 13 is a view showing the internal structure of the driving tool according to embodiment 3. Figure 14 is a partially enlarged view showing the air movement path inside the housing according to embodiment 3. Note that in embodiment 3, the battery pack 50 (see Figures 1 and 2) is not shown.

[0133] 12 to 14, in the third embodiment, the shape of the centrifugal fan 90 attached to the rotary shaft 42a of the brushless motor 40 is different from that in the second embodiment. In addition, in accordance with the change in the shape of the centrifugal fan 90, a plurality of sub-exhaust holes 91 are provided in the motor housing portion 26 that forms the second housing half 80, so as to be aligned above the plurality of second exhaust holes 26t. Furthermore, a partition wall 92 is provided inside the second housing half 80 between the second exhaust holes 26t and the sub-exhaust holes 91 that are aligned in the up-down direction.

[0134] The first housing half 93 also has a plurality of sub-exhaust holes and partition walls (not shown). The sub-exhaust holes and partition walls of the first housing half 93 face the sub-exhaust holes 91 and partition walls 92 of the second housing half 80 in the left-right direction. The detailed structure of the second housing half 80 will be described below with reference to only the second housing half 80.

[0135] The centrifugal fan 90 has a two-story structure. Specifically, a first fan section 90a is provided on the lower level of the centrifugal fan 90, and a second fan section 90b is provided on the upper level of the centrifugal fan 90. The first fan section 90a is located on the side where the stator 41 is provided, below the partition wall 92 (reference line BL), and faces the plurality of second exhaust holes 26t in the left-right direction. In contrast, the second fan section 90b is located on the side where the cylindrical case 45b is provided, above the partition wall 92 (reference line BL), and faces the plurality of sub-exhaust holes 91 in the left-right direction.

[0136] 14 are generated inside second housing half 80. That is, when centrifugal fan 90 is rotated by driving brushless motor 40, air flows into second housing half 80 from multiple second air intake holes 26s on the side of motor housing portion 26 where stator 41 is provided, as shown by air flow FL8. The air that has flowed into second housing half 80 then cools stator 41, and is then discharged to the outside of second housing half 80 from multiple second exhaust holes 26t, as shown by air flow FL9.

[0137] Furthermore, on the side of motor housing portion 26 where cylindrical case 45b is provided, air flows into second housing half 80 through a total of three labyrinth-shaped communication ports 81, as indicated by air flow FL10. At this time, the air is divided into air flow FL10 directed toward second fan portion 90b and air flow FL11 directed toward cylinder 32 of drive mechanism 30. Air flow FL10 flowing into second housing half 80 and directed toward second fan portion 90b passes near second dust collection chamber 26k and second exhaust port 26m (see FIG. 11 ) and is discharged to the outside of second housing half 80 through multiple secondary exhaust holes 91, as indicated by air flow FL12.

[0138] The third embodiment configured as described above can also achieve the same effects as the second embodiment. In addition, in the third embodiment, the action of the second fan section 90b can actively generate airflows FL10, FL12 on the side of the motor housing section 26 where the cylindrical case 45b is provided. This makes it possible to efficiently discharge dust accumulated near the second dust collection chamber 26k and the second exhaust port 26m to the outside of the second housing half 80. This allows the internal environment of the housing 21 to be kept cleaner.

[0139] <Fourth Embodiment> Next, a fourth embodiment of the present invention will be described in detail with reference to the drawings. Note that parts having the same functions as those in the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

[0140] Figure 15 is a diagram showing the internal structure of the driving tool of embodiment 4. Figure 16 is a cross-sectional view taken along line CC in Figure 15. Figure 17 is a perspective view of the driving tool as seen from the front, showing the lever holder and cover separated. Figure 18 is a perspective view of the driving tool as seen from the rear, as seen in Figure 17.

[0141] Fig. 19 is a perspective view illustrating the housing-side entry portion provided on the lever holder. Fig. 20 is a perspective view illustrating the cover-side entry portion provided on the cover. Fig. 21 is a perspective view of the cover alone, showing the inside of the cover. Fig. 22 is a view from below of the driving tool, showing whether or not the housing is present.

[0142] In FIG. 15, the brushless motor 40 and the planetary gear reducer 45 (see FIG. 2) are omitted from the illustration.

[0143] 15 to 18, the driving tool 100 of the fourth embodiment differs from the driving tool 10 of the first embodiment (see FIG. 2) in the shape of the housing 110. In addition, in accordance with the change in the shape of the housing 110, a cover 120 is provided in front of the housing 110.

[0144] <Housing> The housing 110 is divided into a first housing half 111 and a second housing half 112 on the left and right sides of the driving tool 100, and includes a lever holder 113 disposed across the first and second housing halves 111, 112. The housing 110 has a labyrinth mechanism 70 similar to that in the first embodiment, but a detailed description thereof will be omitted.

[0145] The lever holder 113 holds an adjustment lever 113a for adjusting the driving amount (driving depth) of the nail 11 (see FIG. 1) into the mating material W (see FIG. 1). The adjustment lever 113a is connected to a driving amount adjustment mechanism 114 housed inside the housing 110.

[0146] As shown in Figures 17 and 18, the lever holder 113 forming the housing 110 is generally plate-shaped and curved in a generally bow shape. Engagement protrusions TP are provided on both longitudinal sides (left and right sides) of the lever holder 113. These engagement protrusions TP engage with engagement recesses RP (only one side is shown in Figure 17) provided on the inside of the first and second housing halves 111, 112. As a result, the lever holder 113 is supported on both longitudinal sides by the first and second housing halves 111, 112.

[0147] Here, the lever holder 113 is formed in an approximately plate-like shape as shown in Figures 17 and 18, and the first and second housing halves 111, 112 that support the lever holder 113 are also formed in an approximately plate-like shape as shown in Figure 16.

[0148] The front side of the housing 110, which is made up of the first and second housing halves 111, 112 and the lever holder 113, is provided with a housing side end surface 110a facing the front of the driving tool 100. The front side of the housing 110 also has a housing inner surface 110b and a housing outer surface 110c.

[0149] Here, the housing-side end face 110a corresponds to the end face of the housing in the present invention. The housing-side end face 110a faces the cover-side end face 120a in the axial direction (front-rear direction) of the cylinder 32 (see FIG. 16). The housing inner surface 110b and the housing outer surface 110c correspond to the inner and outer surfaces of the housing in the present invention.

[0150] 17 to 19, a housing-side entry portion 113b is integrally provided on the front side of the lever holder 113 that forms the housing 110. The housing-side entry portion 113b is disposed at a position offset toward the inside of the housing 110 with respect to the housing-side end face 110a, and protrudes a predetermined height forward of the lever holder 113. Here, in FIG. 19, the housing-side entry portion 113b is indicated by diagonal lines to make it easier to see.

[0151] When the cover 120 is attached to the housing 110, the housing-side entry portion 113b is inserted into (inserted into) the cover inner surface 120b (see FIG. 21 ) of the cover 120. In other words, when the driving tool 100 is assembled, the housing-side entry portion 113b is not exposed to the outside.

[0152] Also, as shown in Figure 16, a second opening OP2 and a fourth opening OP4 are formed on the front side of the housing 110, i.e., the front sides of the first and second housing halves 111, 112 and the lever holder 113, connecting the inside and outside of the housing 110.

[0153] The tip side (front side) of the nose 31 is disposed inside the second opening OP2 and the fourth opening OP4. The base end side (rear side) of the emission section 34 is inserted and fixed inside the tip side of the nose 31. In other words, the base end side of the emission section 34 is also disposed inside the second opening OP2 and the fourth opening OP4.

[0154] 16, the injection part 34 has a base 34a on its rear side along the front-rear direction, and the base 34a is fixed to the tip side of the nose 31. The cover 120 covers the base 34a that forms the injection part 34. The injection part 34 also has a cylindrical part 34c that protrudes from the base 34a in the injection direction (front side) of the nail 11 (see FIG. 1) and defines an injection path 34b for the nail 11 therein.

[0155] A first gap G1 is provided between the second opening OP2 and the tip side of the nose 31, which includes the base end side of the injection portion 34. A second gap G2 is provided between the fourth opening OP4 and the tip side of the nose 31, which includes the base end side of the injection portion 34. These first and second gaps G1 and G2 communicate between the inside and outside of the housing 110.

[0156] The first and second gaps G1 and G2 correspond to the gaps in the present invention.

[0157] 16 to 18, 20, and 21, the cover 120 is formed by injection molding a resin material such as plastic into a generally plate-like, bowl-like shape. When the cover 120 is attached to the housing 110, the cover 120 covers the first and second gaps G1 and G2 from the front of the driving tool 100.

[0158] A cover bottom 121 is provided on the front side of the cover 120. An insertion hole 121a, through which the front side of the ejection unit 34 is inserted, is provided in the approximate center of the cover bottom 121, and a small gap (micro gap) is formed between the insertion hole 121a and the ejection unit 34. In other words, it is difficult for air containing dust to flow into the interior of the cover 120 (housing 110) from between the insertion hole 121a and the ejection unit 34.

[0159] The rear side of the cover 120 is open, and the rear side of the cover 120 is provided with a cover-side end surface 120a facing the rear of the driving tool 100. Furthermore, the rear side of the cover 120 is provided with a cover inner surface 120b and a cover outer surface 120c.

[0160] Here, the cover-side end face 120a corresponds to the end face of the cover in the present invention. The cover-side end face 120a faces the housing-side end face 110a in the axial direction (front-rear direction) of the cylinder 32 (see FIG. 16). The cover inner surface 120b and the cover outer surface 120c correspond to the inner and outer surfaces of the cover in the present invention, respectively.

[0161] Furthermore, cover-side entry sections 122 are integrally provided on the left and right sides of the rear of the cover 120 (see FIG. 16 ). These cover-side entry sections 122 are disposed at positions offset inward from the cover 120 relative to the cover-side end face 120a, and protrude a predetermined height rearward from the cover 120. In FIG. 20 , the cover-side entry sections 122 are indicated by diagonal lines to make them easier to understand. In FIG. 20 , only one cover-side entry section 122 (the left side) is shown.

[0162] When the cover 120 is attached to the housing 110, the pair of cover-side entry sections 122 are inserted into (inserted into) the housing inner surface 110b (see FIG. 16) of the housing 110. In other words, when the driving tool 100 is assembled, the pair of cover-side entry sections 122 are not exposed to the outside.

[0163] 21, a pair of cover fixing portions 123 for fixing the cover 120 to the nose 31 are integrally formed on the inside of the cover 120. Each of the cover fixing portions 123 is provided with a bolt insertion hole 123a through which a hexagon socket head bolt BT (see FIG. 22) is inserted.

[0164] The hexagon socket head bolt BT corresponds to the fixing tool in this invention.

[0165] Specifically, these bolt insertion holes 123a penetrate the cover 120 in the vertical direction. Therefore, for example, the bolt heads of the hexagon socket head bolts BT do not have to protrude from the left and right sides of the driving tool 100, making the front side of the driving tool 100 neater and improving its design.

[0166] 16, the pair of hexagon socket head bolts BT are screwed into a pair of threaded holes SH provided in a portion of the nose 31 near the tip end thereof. In this manner, the cover 120 is screwed to the nose 31, and the nose 31 is fixed to the front end of the cylinder 32, as shown in FIG.

[0167] In this way, the ejection section 34 and the cover 120 are both fixed to the nose 31 which is fixed to the cylinder 32. As a result, when the drive mechanism 30 is driven (during an impact operation), the ejection section 34 and the cover 120 vibrate together with the nose 31. In other words, the ejection section 34 and the cover 120 do not vibrate (move relatively) independently of each other.

[0168] Therefore, it is possible to almost completely eliminate the gap between the ejection portion 34 and the cover 120. As a result, it is possible to prevent almost all dust-containing air from flowing into the inside of the cover 120 (housing 110) from between the insertion hole 121a and the ejection portion 34.

[0169] 16 , the cylinder 32 forming the drive mechanism 30 is supported by the first housing half 111 and the second housing half 112 forming the housing 110 via a plurality of cushion rubbers CR. Therefore, vibrations generated when the drive mechanism 30 is driven are less likely to be transmitted to the housing 110. This can reduce fatigue of an operator who grips the handle portion 25 of the housing 110, for example.

[0170] The cushion rubber CR corresponds to the elastic body in the present invention.

[0171] As described above, when the drive mechanism 30 is driven, the cover 120 vibrates, while the housing 110 is less likely to vibrate. In other words, the cover 120 and the housing 110 need to be connected so that they can move relative to each other without being fixed to each other. Therefore, in the driving tool 100 of the fourth embodiment, the housing-side entry portion 113b on the housing 110 enters the inner cover surface 120b of the cover 120 without being fixed to each other (see FIG. 18 ). Furthermore, the pair of cover-side entry portions 122 on the cover 120 enter the inner housing surface 110b of the housing 110 without being fixed to each other (see FIG. 16 ).

[0172] This allows the housing 110 and the cover 120 to move relative to each other in the front-to-rear direction, thereby blocking the vibration transmission path at the connection between the housing 110 and the cover 120. This prevents dust-containing air from flowing into the interior of the cover 120 and the housing 110 from between the insertion hole 121a and the ejection portion 34, while suppressing vibration of the housing 110 including the handle portion 25.

[0173] Here, the housing-side entry portion 113b and the cover-side entry portion 122 are disposed adjacent to each other in the circumferential direction around the axis of the injection portion 34, and are arranged alternately in the circumferential direction (see FIGS. 19 and 20). Therefore, the cover 120 and the housing 110 behave as follows at their respective joint portions.

[0174] For example, if an external force is applied to the upper side of the cover 120, such as when something hits the driving tool 100, the outer cover surface 120c of the cover 120 is pushed down. At this time, the housing-side entry portion 113b on the housing 110 supports the cover 120 so as not to deform it. Therefore, deformation of the cover 120 due to the application of the external force is suppressed.

[0175] The lever holder 113 is supported by the first and second housing halves 111, 112 only by the engaging projections TP on both sides of its length. Therefore, the center of the lever holder 113 in the length direction, i.e., the housing-side entry portion 113b, acts as a cushion. This effectively prevents damage to the lever holder 113, including the cover 120.

[0176] Furthermore, when an external force is applied to the upper side of the cover 120, the cover 120 tends to bulge out to the left or right, but the pair of cover-side entry portions 122 of the cover 120 are respectively disposed on the housing inner surface 110b side of the housing 110. Therefore, the housing 110 (first and second housing halves 111, 112) prevents the cover 120 from bulging out to the left or right. This also prevents the cover 120 from being deformed when an external force is applied.

[0177] In this way, when an external force is applied to the upper side of the cover 120, the external force is dispersed and transmitted to the housing 110. This prevents early damage to the cover 120 alone due to stress concentration, etc. Furthermore, even if the cover 120 and the housing 110 (first and second housing halves 111, 112) are distorted due to, for example, aging, the respective "distortions" are transmitted to each other, thereby preventing the occurrence of gaps between the cover 120 and the housing 110. This prevents dust-laden air from entering the interior of the housing 110 through the connecting portion between the cover 120 and the housing 110 over a long period of time.

[0178] To assemble the driving tool 100, first, the cover 120 is screwed to the nose 31 with a pair of hexagon socket head bolts BT, as shown in the left side of Fig. 22. This secures the cover 120 to the nose 31. Then, as shown in the right side of Fig. 22, the housing 110 (first and second housing halves 111, 112) is assembled.

[0179] 22, one (right) of the pair of hexagon socket head bolts BT is covered by the second housing half 112. In other words, the housing 110 covers and conceals one of the hexagon socket head bolts BT, and as a result, the cover 120 cannot be removed unless the housing 110 is disassembled.

[0180] The fourth embodiment configured as described above can also achieve the same effects as those of the first embodiment. In addition, in the fourth embodiment, first and second gaps G1, G2 that communicate between the inside and outside of the housing 110 are provided between the emission portion 34 and the second and fourth openings OP2, OP4, and the first and second gaps G1, G2 are covered by the cover 120.

[0181] This makes it possible to more effectively prevent air containing dust from flowing into the interior of the housing 110, particularly from the front part of the driving tool 100 that is close to the mating material W (an area with a lot of dust).

[0182] In addition, in embodiment 4, the injection unit 34 has a base 34a and a cylindrical portion 34c that protrudes from the base 34a in the injection direction of the nail 11 and defines an injection path 34b for the nail 11 therein, and the cover 120 covers the base 34a.

[0183] This allows parts of the drive mechanism 30, such as the nose 31, located on the base end side of the ejection section 34, to be covered and protected from dust, etc. Also, parts of the drive mechanism 30, such as the nose 31, can be protected from impacts from external forces. Furthermore, a structure can be achieved that makes it difficult to disassemble the driving tool 100.

[0184] Furthermore, in the fourth embodiment, the injection section 34 and the cover 120 are each fixed to the nose 31 that forms the drive mechanism 30, and the nose 31 is attached to the housing 110 via the cylinder 32 and the cushion rubber CR.

[0185] This allows the ejection unit 34 and the cover 120 to vibrate together when the drive mechanism 30 vibrates (when the driving tool 100 is driven), thereby closing the gap between them. This makes it possible to more effectively prevent dust-laden air from flowing into the housing 110 from between the ejection unit 34 and the cover 120.

[0186] In addition, in the fourth embodiment, the cover 120 is fixed to the nose 31 by a pair of hexagon socket head bolts BT, one of which is covered by the housing 110 .

[0187] This allows the driving tool 100 to have a structure that cannot be easily disassembled. However, although one of the hexagon socket head bolts BT is covered by the second housing half 112 in the fourth embodiment, the other hexagon socket head bolt BT can also be covered by the first housing half 111.

[0188] Furthermore, in embodiment 4, the housing 110 and the cover 120 each have a housing side end face 110a and a cover side end face 120a that face each other in the axial direction (front-to-back direction) of the cylinder 32, and are plate-shaped with a housing inner surface 110b, a cover inner surface 120b, and a housing outer surface 110c, a cover outer surface 120c, respectively, and the cover 120 has a cover side entry portion 122 that enters the housing inner surface 110b side of the housing 110.

[0189] As a result, when an external force is applied from above the cover 120, the cover 120 tends to bulge out to the left or right, but the first and second housing halves 111, 112 that form the housing 110 support the cover 120 so that it does not bulge out further to the left or right. This prevents the cover 120 from being significantly deformed, and ultimately prevents damage to the cover 120.

[0190] In the fourth embodiment, the housing 110 has a housing-side entry portion 113b that enters the cover inner surface 120b of the cover 120, and the cover-side entry portion 122 and the housing-side entry portion 113b are adjacent to each other.

[0191] This allows external forces transmitted to the cover 120 to be dispersed and transmitted to the housing 110. This prevents premature damage to the cover 120 alone due to stress concentration, etc. Furthermore, even if the cover 120 and the housing 110 are distorted due to changes over time, the respective "distortions" are transmitted to each other, preventing gaps from forming between them. This also effectively prevents dust-laden air from entering the housing 110.

[0192] The present invention is not limited to the above-described embodiments and may be modified in various ways without departing from the spirit and scope of the present invention. For example, as shown by the dashed line in FIG. 9 , a sponge sheet SS may be attached to the third main inclined wall 73 forming the labyrinth mechanism 70. In this case, the sponge sheet SS allows air to pass through while capturing dust, thereby further preventing dust from reaching the interior of the cylinder 32. Furthermore, the lubricant (not shown) applied between the cylinder 32 and the seal member 35d (see FIG. 3 ) attached to the piston 35a can also be prevented from reaching the first and second dust storage chambers 26a and 26k. This effectively prevents dust from collecting and remaining in the first and second dust storage chambers 26a and 26k.

[0193] Furthermore, in each of the above-described embodiments, the working machine is shown to be a driving machine 10 that ejects nails 11 from the ejection unit 34, but the present invention is not limited to this and can also be applied to working machines that have an impact unit (operating unit) that performs linear motion, such as an electric tacker.

[0194] Furthermore, the material, shape, size, number, installation location, etc. of each component in each of the above-described embodiments may be any as long as it can achieve the present invention, and is not limited to each of the above-described embodiments.

[0195] 10... driving tool (working machine), 11... nail (fastener), 20... driving tool body, 21... housing, 22... first housing half (housing), 22a... first cylinder accommodating chamber, 22b... first injection part accommodating chamber (communicating passage), 22c... first connection space portion (communicating passage), 23... second housing half (housing), 23a... second cylinder accommodating chamber, 23b... second injection part accommodating chamber (communicating passage), 23c... second connection space portion (communicating passage), 24... main body housing portion, 25... handle portion, 26... motor housing portion, 26a... First dust storage chamber (dust storage chamber), 26b...first exhaust port (exhaust port), 26c...first guide wall (guide wall), 26d...first bottom wall portion, 26e...first ceiling wall portion, 26f...first brushless motor storage portion, 26g...first air intake hole, 26h...first exhaust hole, 26k...second dust storage chamber (dust storage chamber), 26m...second exhaust port (exhaust port), 26n...second guide wall (guide wall), 26p...second bottom wall portion, 26q...second ceiling wall portion, 26r...first brushless motor storage portion, 26s...second air intake hole, 26t...second exhaust hole, 27...battery pack rack mounting portion, 28... hollow portion, 30... drive mechanism (operating portion), 31... nose, 31a... nose main body portion, 31b... bumper, 32... cylinder, 32a... through hole (inlet hole), 33... pressure accumulator vessel, 33a... pressure chamber, 34... injection portion, 34a... base portion, 34b... injection path, 34c... cylindrical portion, 35a... piston, 35b... driver blade (blade), 35c... rack, 35d... seal member, 36... pinwheel, 36a... pin, 37... push lever, 40... brushless motor (motor), 41... step motor, 42... rotor, 42a... rotating shaft, 42b... centrifugal fan, 43... controller, 44... trigger switch, 44a... limit switch, 45... planetary gear reducer, 45a... gear mechanism (transmission mechanism), 45b... cylindrical case (labyrinth mechanism), 50... battery pack, 60... magazine, 61... magazine case, 62... feeder, 70... labyrinth mechanism, 71... first main inclined wall (labyrinth mechanism), 72... second main inclined wall (cross wall, labyrinth mechanism), 73... third main inclined wall (cross wall,labyrinth mechanism), 74...sub-inclined wall (labyrinth mechanism), 80...second housing half (housing), 81...labyrinth-shaped communication port, 81a...hole portion, 81b...opposing wall, 90...centrifugal fan, 90a...first fan portion, 90b...second fan portion, 91...sub-exhaust hole, 92...partition wall, 93...first housing half (housing), 100...driving tool, 110...housing, 110a...housing side end face (end face), 110b...housing inner surface (inner surface), 110c...housing outer surface (outer surface), 111...first housing half (housing), 112...second housing half (housing), 113...lever holder (housing), 113a...adjusting lever, 113b...housing side entry portion, 114...driving amount adjustment mechanism, 120...cover, 120a...cover side end face (end face), 120b... Cover inner surface (inner surface), 120c: cover outer surface (outer surface), 121...cover bottom, 121a...insertion hole, 122...cover side entry portion, 123...cover fixing portion, 123a...bolt insertion hole, BL...reference line, BT...hexagon socket head bolt (fixing device), CR...cushion rubber (elastic body), CV...cover member, FL1 to FL12...air flow, G1...first gap (gap), G2...second gap (gap), OP1... First opening (opening, first opening, third opening), OP2... second opening (opening, second opening, third opening), OP3... third opening (opening, first opening, third opening), OP4... fourth opening (opening, second opening, third opening), PS1... first air passage (first passage), PS2... second air passage (second passage), RP... engaging recess, SH... screw hole, SS... sponge sheet, TP... engaging protrusion, W... mating material,

Claims

1. A work machine comprising: an ejection section that supports a fastener; an actuation section that applies an impact force to the fastener supported by the ejection section; a housing that houses at least a portion of the ejection section and the actuation section and has an opening; and a labyrinth mechanism that is provided in the housing and prevents dust that has entered the housing through the opening from reaching the actuation section.

2. A work machine as described in claim 1, wherein the labyrinth mechanism is provided in a communication passage that connects the opening and the operating part, and bends the flow of air passing through the communication passage.

3. A work machine as described in claim 2, wherein the housing defines a first passage that is part of the communication passage and extends in a first direction, and the labyrinth mechanism includes a cross wall that extends in a second direction that intersects with the first direction and has one end located in the first passage, and that bends the flow of air circulating through the first passage.

4. The work machine according to claim 3, wherein the housing is disposed adjacent to the other end of the cross wall and defines a dust storage chamber for storing dust contained in the air.

5. A work machine according to claim 4, wherein the housing has an outlet that connects the dust chamber to the outside of the housing.

6. The work machine according to claim 5, wherein the housing is provided with a guide wall disposed between the other end of the cross wall and the discharge port to guide the dust to the discharge port.

7. The work machine according to claim 3, wherein the cross wall is inclined so as to extend in both the first direction and the second direction.

8. A work machine as described in claim 2, wherein the housing defines a second passage that is part of the communication passage and extends in a third direction, the housing is provided inside with a motor and a cylindrical case that houses a transmission mechanism that transmits the driving force of the motor to the operating part, and the labyrinth mechanism is formed by the cylindrical case and bends the air flowing through the second passage.

9. A work machine as described in claim 1, wherein the operating part includes a cylinder, a piston that is movable inside the cylinder in the axial direction of the cylinder, and a rod-shaped blade that extends from the piston in the axial direction and strikes the stopper by moving in the axial direction of the cylinder, the cylinder having an inlet hole through which air flows in as the piston moves, and the labyrinth mechanism is arranged between the opening and the inlet hole.

10. A work machine as described in claim 1, wherein a magazine that supplies the fasteners is connected to the ejection section, and the opening includes a first opening that serves as a passage for the magazine to extend from the inside to the outside of the housing.

11. A work machine as described in claim 1, wherein the injection portion protrudes in the axial direction from the inside to the outside of the housing, and the opening includes a second opening that serves as a passage through which the injection portion extends from the inside to the outside of the housing.

12. A work machine as described in claim 11, wherein a gap communicating the inside and outside of the housing is provided between the injection portion and the second opening, and the gap is covered by a cover.

13. A work machine as described in claim 12, wherein the injection section has a base and a cylindrical section that protrudes from the base in the injection direction of the fastener and defines an injection path for the fastener therein, and the cover covers the base.

14. A work machine according to claim 12, wherein the ejection unit and the cover are each fixed to the operating unit, and the operating unit is attached to the housing via an elastic body.

15. The work machine according to claim 14, wherein the cover is fixed to the operating part by a fastener, and the fastener is covered by the housing.

16. A work machine as described in claim 14, wherein the housing and the cover each have end faces that face each other in the axial direction of the operating part, and are plate-shaped with inner and outer surfaces, and the cover has a cover-side entry portion that enters the inner surface of the housing.

17. A work machine according to claim 16, wherein the housing has a housing-side entry portion that enters the inner surface of the cover, and the cover-side entry portion and the housing-side entry portion are adjacent to each other.

18. The work machine according to claim 1, wherein the opening includes a third opening arranged in a region overlapping the operating portion in a direction in which the operating portion applies a striking force to the stopper.

19. A work machine comprising: an ejection section that supports a stopper; a cylinder; a piston that is movable inside the cylinder in the axial direction of the cylinder; a rod-shaped blade extending from the piston in the axial direction and that strikes the stopper by moving in the axial direction of the cylinder; and a housing that contains the ejection section and at least a part of the cylinder, wherein the cylinder has an inlet hole through which air flows in as the piston moves, the ejection section protruding from the housing in the axial direction, the housing has an opening and defines a communication passage therein that communicates the opening with the inlet hole, and the housing has one end located in a first passage that is part of the communication passage and extends in a first direction, and includes a cross wall that extends in a second direction that intersects the first direction and bends the flow of air flowing through the first passage.

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