Work equipment

Abstract

The present invention improves the durability of a work machine. In this work machine, a driving machine comprises: an electric motor; a striking element 112 which is capable of striking a stopper by being moved toward the lower side in the vertical direction D1; a biasing part which biases the striking element 112 toward the lower side in the vertical direction D1; and a rotary part which comprises a first gear 151, a second gear 152, and a third gear 153 that move the striking element 112 toward the upper side in the vertical direction D1. The rotary part includes a wheel 150 and a plurality of engagement parts that are disposed so as to be engageable with the striking element 112. The engagement parts include: a second pin 152a and a third pin 152b that engage with the striking element 112 when the striking element 112 is to be moved toward the upper side in the vertical direction D1; and a stopper pin 152c that is not engaged with the striking element 112 when the striking element 112 is to be moved toward the upper side in the vertical direction D1.

Description

[Technical Field]

[0001] The present invention relates to a work machine such as a driving machine. [Background technology]

[0002] 2. Description of the Related Art As an example of a work machine, a driving tool is known that has a motor, a striking unit capable of striking a fastener, and a rotating unit that rotates by the driving force of the motor.

[0003] As an example of such a driving machine, Patent Document 1 discloses a driving machine having a pinwheel as a component of the rotating part and a plunger as the striking part, in which the pin on the pinwheel engages with the plunger to wind up the plunger. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-19078 Summary of the Invention [Problem to be solved by the invention]

[0005] With the driving tool described in Patent Document 1, there is a concern that a blank strike may occur, in which the plunger erroneously moves to the bottom dead center due to damage to the pin on the pinwheel, etc. Because blank strikes can lead to damage to the plunger, there is a need to improve the durability of the driving tool.

[0006] An object of the present invention is to provide a work machine with improved durability. [Means for solving the problem]

[0007] The working machine of the present invention comprises a driving source, an impact section capable of striking a stopper by moving to one side in a first direction, a biasing section that biases the impact section toward one side in the first direction, and a rotating section that rotates by the driving force of the driving source to move the impact section toward the other side in the first direction, wherein the rotating section includes a base and a plurality of engaging sections provided on the base so as to be engageable with the impact section, and the plurality of engaging sections include a first engaging section that engages with the impact section when the impact section is moved to the other side in the first direction, and a second engaging section that does not engage with the impact section when the impact section is moved to the other side in the first direction. Another working machine of the present invention comprises a drive source, an impact unit capable of striking a stopper by moving toward one side in a first direction, a biasing unit that biases the impact unit toward one side in the first direction, and a rotating unit that rotates by the drive force of the drive source to move the impact unit toward the other side in the first direction, wherein the rotating unit includes a base, and a first engagement unit and a second engagement unit that are provided on the base and are capable of engaging with the impact unit, and the rotating unit rotates with the first engagement unit engaged with the impact unit to move the impact unit to a top dead center position, and after the impact unit reaches the top dead center position, the rotating unit disengages the first engagement unit from the impact unit, causing the impact unit to strike the stopper, and the second engagement unit engages with the impact unit when the engagement between the first engagement unit and the impact unit is released after the first engagement unit and the impact unit engage but before the impact unit reaches the top dead center position. [Effects of the Invention]

[0008] According to the present invention, the durability of the work machine can be improved. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a side cross-sectional view showing the structure of a working machine according to an embodiment of the present invention. [Figure 2] 2A and 2B are diagrams showing the structure of the hoisting mechanism of the work machine shown in FIG. 1, in which (a) is a left side view and (b) is a right side view. [Figure 3] 3A and 3B are diagrams showing the structure of the winding mechanism shown in FIG. 2, where (a) is a front view and (b) is a rear view. [Figure 4] 2 is a cross-sectional view showing the structure of the working machine shown in FIG. 1 taken along line AA. [Figure 5] 3A to 3C are diagrams showing the meshing structure of gears provided in the winding mechanism shown in FIG. 2, where (a) is a side view, (b) is a front view, and (c) is a perspective view. [Figure 6] 3A, 3B, and 3C are diagrams showing the state of the winding mechanism shown in FIG. 2 at the bottom dead center position, where FIG. 3A is a rear view, FIG. 3B is a right side view, and FIG. 3C is a front view. [Figure 7] 3A to 3C are diagrams showing the state of the winding mechanism shown in FIG. 2 during winding, where (a) is a rear view, (b) is a right side view, and (c) is a front view. [Figure 8]3A to 3C are diagrams showing the state of the winding mechanism shown in FIG. 2 during winding, where (a) is a rear view, (b) is a right side view, and (c) is a front view. [Figure 9] 3A, 3B, and 3C are diagrams showing the standby position of the striking unit in the winding mechanism shown in FIG. 2, in which (a) is a rear view, (b) is a right side view, and (c) is a front view. [Figure 10] 3A, 3B, and 3C are diagrams showing the state of the winding mechanism shown in FIG. 2 at the top dead center position, where FIG. 3A is a rear view, FIG. 3B is a right side view, and FIG. 3C is a front view. [Figure 11] 10A to 10C are diagrams showing a state in which the plunger is supported by the second engagement portion when the plunger is lowered from the state shown in FIG. 9, where (a) is a rear view, (b) is a right side view, and (c) is a front view. [Figure 12] 3A to 3C are diagrams showing a state in which the plunger is pushed up by the second protrusion in the winding mechanism shown in FIG. 2, where (a) is a rear view, (b) is a right side view, and (c) is a front view. [Figure 13] 13A to 13C are diagrams showing a state in which the plunger is supported by the second engagement portion when the plunger is lowered from the state shown in FIG. 12, where (a) is a rear view, (b) is a right side view, and (c) is a front view. [Figure 14] 3 is a schematic diagram showing the protrusion amounts of the rack of the plunger and the pin of the gear of the winding mechanism shown in FIG. 2. FIG. [Figure 15] 3 is a schematic diagram showing the positional relationship between the rack of the plunger and the pin of the gear when the winding mechanism shown in FIG. 2 is in the standby position, as viewed in a first direction. FIG. [Figure 16] 10A and 10B are diagrams showing the structure of a pinwheel according to a modified example of an embodiment of the present invention, in which (a) is a front view and (b) is a perspective view. DETAILED DESCRIPTION OF THE INVENTION

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

[0011] In this embodiment, a coil spring type fastener driving tool will be described as an example of a work machine. The fastener driving tool 100 shown in FIGS. 1 to 4 includes a housing 111, a striking unit 112, a magazine 113, an electric motor (drive source) 114, a transmission mechanism (winding mechanism) 115, a control unit 116, a battery pack 117, and a counterweight 118. The housing 111 includes a cylindrical body 119, a handle 120 connected to the body 119, and a motor case 121 connected to the body 119. A mounting unit 122 is connected to the handle 120 and the motor case 121. The battery pack 117 is attached to the mounting unit 122. The tip of the body 119 is provided with an ejection unit 123 having an ejection path 124, and the ejection unit 123 supports a fastener 125 to be struck by the striking unit 112. The injection part 123 is fixed to the body part 119, and an operator can grip the handle 120 with his / her hand and press the tip of the injection part 123 against the target workpiece W1.

[0012] The motor case 121 is disposed between the handle 120 and the magazine 113 in the direction of the center line E1. The magazine 113 houses a plurality of fasteners 125. The fasteners 125 include nails and are rod-shaped. The magazine 113 has a feeder that sends the fasteners 125 housed in the magazine 113 to the ejection path 124.

[0013] Striking portion 112 is a member that is provided across the inside and outside of body portion 119 and is capable of striking fastener 125 by moving to one side (downward) in the up-and-down direction (first direction) D1. In detail, striking portion 112 has a plunger 126 that is disposed inside body portion 119 and a driver blade 127 that is attached to plunger 126. Driver blade 127 is a member that is used to drive fastener 125 and is made of metal. Plunger 126 to which driver blade 127 is attached is made of metal or synthetic resin.

[0014] 4 is provided inside the body 119. A center line E1 passes through the center of the guide shaft 128. The guide shaft 128 is fixed to a top cover 129 and a bottom holder 130.

[0015] 1, as described above, the driving tool 100 includes the electric motor 114, the striking unit 112 that is driven by the driving force of the electric motor 114 and strikes the fastener 125 while reciprocating in the up-down direction D1, and the housing 111 that houses the electric motor 114 and the striking unit 112. Here, the up-down direction D1 includes a striking direction D2 in which the striking unit 112 strikes the fastener 125 and a return direction D3 that is the direction opposite to the striking direction D2. That is, when the striking unit 112 strikes the fastener 125, the striking unit 112 moves to one side (downward) in the up-down direction D1, and when the striking unit 112 returns, the striking unit 112 moves to the other side (upward) in the up-down direction D1.

[0016] Also provided within the body 119 are a coil spring (biasing portion) 136 that is extendable and contractible in the vertical direction D1 and biases the striking portion 112 toward one (downward) side in the vertical direction D1, and a plunger 126 that abuts against an end of the spring 136 in the striking direction D2 and is capable of striking the stopper 125. More specifically, provided within the body 119 of the housing 111 are the plunger 126, the spring 136, a guide shaft 128, and a counterweight 118 that abuts against an end of the spring 136 in the return direction D3. Also provided within the body 119 is a transmission mechanism 115 that is driven by the driving force of the electric motor 114 and biases the plunger 126 toward the end of the spring 136 in the return direction D3 and biases the counterweight 118 toward the end of the spring 136 in the striking direction D2, thereby compressing the spring 136. Here, the transmission mechanism 115 includes, for example, a first gear 151, a second gear 152, and a third gear 153 shown in FIGS. 2 and 3. Each of the first gear 151, the second gear 152, and the third gear 153 is provided with a pin, and is a rotating part also called a pinwheel. That is, the rotating part includes a wheel 150 serving as a base and a plurality of engaging parts provided on the wheel 150 so as to be engageable with the striking part 112. The first gear 151, the second gear 152, and the third gear 153 are rotated by the driving force of the electric motor 114, thereby moving the striking part 112 to the other (upward) side in the vertical direction D1. Both sides of the transmission mechanism 115 are supported by a guide bar 131. In other words, the movement of the striking part 112 is guided by the guide bar 131. 2, a latch 132 that restricts the movement of the counterweight 118 is rotatably attached to the guide bar 131. Inside the body 119, there are provided a weight bumper 137 (shown in FIG. 4) against which the counterweight 118 can come into contact when released from the biasing force of the transmission mechanism 115, and a plunger bumper 138 against which the plunger 126 can come into contact.

[0017] Next, the function and operation of each member involved in striking the fastener 125 in the driving tool 100 will be described in detail.

[0018] As shown in FIG. 4, the plunger 126 is attached to the outer peripheral surface of the guide shaft 128 and is operable along the guide shaft 128 in the direction of the center line E1. The guide shaft 128 positions the plunger 126 radially around the center line E1. The driver blade 127 shown in FIG. 3 is operable parallel to the center line E1 together with the plunger 126. The driver blade 127 is operable within the injection passage 124 shown in FIG. 1.

[0019] The counterweight 118 is a member that suppresses the reaction force received by the housing 111, and is attached to a guide shaft 128. The counterweight 118 is movable in the direction of the center line E1 along the guide shaft 128. The guide shaft 128 positions the counterweight 118 radially relative to the center line E1.

[0020] As described above, the spring 136 is provided within the body 119, and is disposed between the plunger 126 and the counterweight 118 in the direction of the center line E1. As an example, the spring 136 may be a compression coil spring in which a metal wire is wound in a spiral shape. The spring 136 is expandable and contractible in the direction of the center line E1. The end of the spring 136 on the bottom holder 130 side in the direction of the center line E1 directly or indirectly contacts the plunger 126.

[0021] Meanwhile, the end of the spring 136 on the top cover 129 side in the direction of the center line E1 directly or indirectly contacts the counterweight 118. The spring 136 receives a compressive force in the direction of the center line E1 and stores elastic energy. The spring 136 is an example of a biasing mechanism that biases the striking part 112 and the counterweight 118.

[0022] The plunger 126 receives a biasing force from the spring 136 in a striking direction D2 that moves the plunger 126 toward the bottom holder 130 in the direction of the center line E1. The counterweight 118 receives a biasing force from the spring 136 in a return direction D3 that moves the plunger 126 toward the top cover 129 in the direction of the center line E1. The striking direction D2 and the return direction D3 are opposite to each other and are parallel to the center line E1. The plunger 126 and the counterweight 118 receive a biasing force from the spring 136, which is the same physical element.

[0023] 4, a weight bumper 137 and a plunger bumper 138 are provided inside the body 119. The weight bumper 137 is disposed between the top cover 129 and the counterweight 118. The plunger bumper 138 is disposed between the bottom holder 130 and the plunger 126. The weight bumper 137 and the plunger bumper 138 are both made of synthetic rubber.

[0024] 1 can be attached to and detached from the mounting portion 122. The battery pack 117 is a DC power source, and the power of the battery pack 117 can be supplied to the electric motor 114. In other words, the electric motor 114 is driven by the power of the battery pack 117. The mounting portion 122 also contains a control portion 116 of the driving tool 100.

[0025] The driving tool 100 has a trigger (operating unit) 142 and a trigger switch 143 provided on the handle 120. The trigger 142 is operated by the operator. When the operator applies an operating force to the trigger 142, the trigger switch 143 turns on. When the operator releases the operating force applied to the trigger 142, the trigger switch 143 turns off.

[0026] The electric motor 114 has a rotor and a stator (not shown), and a motor shaft 146 is attached to the rotor. When electric power is supplied from a battery pack 117, the motor shaft 146 of the electric motor 114 rotates. A reducer (not shown) disposed in the motor case 121 has multiple sets of planetary gear mechanisms, an input element 148, and an output element 149. The input element 148 is connected to the motor shaft 146. The transmission mechanism 115 converts the rotational force of the output element 149 into an operating force for the striking unit 112 and an operating force for the counterweight 118.

[0027] Next, the detailed structure and operation of the transmission mechanism 115, which is a winding mechanism provided in the driving tool 100, will be described. As shown in FIGS. 5(a), (b), and (c), the transmission mechanism 115 includes a first gear 151, a second gear 152, and a third gear 153. The outer diameters of the first gear 151, the second gear 152, and the third gear 153 are the same. The second gear 152 meshes with the first gear 151 and the third gear 153. As a result, when the first gear 151 rotates in a rotational direction R1 due to the driving force of the electric motor 114, the second gear 152 rotates in a rotational direction R2. Furthermore, when the second gear 152 rotates in the rotational direction R2, the third gear 153 rotates in a rotational direction R3.

[0028] The first gear 151 is provided with a first pin 151a, the second gear 152 is provided with a second pin (first engagement portion, second protrusion) 152a and a third pin (first engagement portion, first protrusion) 152b, and the third gear 153 is provided with a fourth pin 153a and a fifth pin 153b that can engage with the counterweight 118. These pins are also called cam rollers. The second pin 152a and the third pin 152b are different pins, and the third pin 152b is longer (has a greater protrusion amount) than the second pin 152a. The second gear 152 is provided with a stopper pin (second engagement portion) 152c. The stopper pin 152c has the same shape as the second pin 152a. In other words, the stopper pin 152c and the second pin 152a have the same length (protrusion amount). In the second gear 152, the second pin 152a, the third pin 152b, and the stopper pin 152c are arranged on the same circumference. The stopper pin 152c is arranged rearward of the second pin 152a in the rotation direction R2 of the second gear 152. Furthermore, the stopper pin 152c is arranged between the second pin 152a and the third pin 152b in the rotation direction R2 of the second gear 152. In the third gear 153, the fourth pin 153a and the fifth pin 153b are also arranged on the same circumference. Each pin is provided rotatably relative to each gear.

[0029] 6 to 13, the plunger 126 has a first rack 126a that can be engaged with the first pin 151a of the first gear 151, and also has a second rack (first engaged portion) 126b that can be engaged with the second pin 152a of the second gear 152. Furthermore, the plunger 126 also has a third rack (second engaged portion) 126c that can be engaged with the third pin 152b of the second gear 152.

[0030] 14, the second pin 152a and the stopper pin 152c are formed of pins of the same shape, and therefore the second pin 152a and the stopper pin 152c protrude from the second gear 152 by the same amount. Furthermore, the second pin 152a can engage with the second rack 126b of the plunger 126, and therefore the stopper pin 152c can also engage with the second rack 126b (part P2). Furthermore, the second pin 152a and the stopper pin 152c are both short pins, and therefore do not engage with the first rack 126a or the third rack 126c of the plunger 126 (parts P1 and P3). That is, the stopper pin 152c is positioned so that it does not engage with the first rack 126a or the third rack 126c during the normal winding operation of the transmission mechanism 115 (the operation of moving the striking part 112 upward in the vertical direction D1), and does not engage with the second rack 126b at the timing of the normal winding operation. In other words, the stopper pin 152c does not engage with any rack during the normal winding operation, and the normal winding operation is not hindered by the stopper pin 152c.

[0031] As described above, in the driving tool 100 of this embodiment, the multiple pins (engagement portions) provided on each gear of the transmission mechanism 115 include the second pin 152a and the third pin 152b that engage with the striking portion 112 when the striking portion 112 is moved upward in the vertical direction D1, and the stopper pin 152c that does not engage with the striking portion 112 when the striking portion 112 is moved upward in the vertical direction D1. In other words, the stopper pin 152c is a pin that engages with the second rack 126b of the plunger 126 when the engagement between the second pin 152a and the third pin 152b and the plunger 126 is released and the plunger 126 moves downward in the vertical direction D1.

[0032] Here, a situation in which the stopper pin 152c and the second rack 126b of the plunger 126 engage will be described. In a standby state in which the trigger 142 is not operated (the standby state shown in FIG. 9), the plunger 126 engages with the third pin 152b. That is, in a standby state in which the trigger 142 is not operated, the plunger 126 is supported by the third pin 152b. At this time, the standby position at which the striking part 112 is positioned in the standby state is a position between the top dead center position and the bottom dead center position of the movement of the striking part 112 in the up-down direction D1. In the standby state at this standby position, for example, if the third pin 152b is broken or the like and the plunger 126 descends, the stopper pin 152c engages with the second rack 126b of the plunger 126, as shown in FIG. 11, to stop the descent of the plunger 126. That is, if the third pin 152b breaks or the like and the plunger 126 descends in the standby state, the second rack 126b of the plunger 126 engages with the stopper pin 152c, causing the second rack 126b of the plunger 126 to be caught on the stopper pin 152c. This prevents the plunger 126 from falling. Alternatively, if the second pin 152a engages with the second rack 126b of the plunger 126 and pushes up the plunger 126 during the winding operation of the transmission mechanism 115 shown in FIG. 12, if the second pin 152a breaks or the like and the plunger 126 descends, the stopper pin 152c engages with the second rack 126b of the plunger 126, as shown in FIG. 13, to stop the descent of the plunger 126. That is, if the second pin 152a is broken or the like and the plunger 126 drops while the second pin 152a is pushing up the plunger 126, the second rack 126b of the plunger 126 engages with the stopper pin 152c, and the second rack 126b of the plunger 126 is caught on the stopper pin 152c. This prevents the plunger 126 from falling.

[0033] Next, the winding operation of the transmission mechanism 115 will be described with reference to FIGS. 6 to 10 and 12. FIG.

[0034] The driving tool 100 has a standby state in which the operator does not operate the trigger 142. The standby state is shown in FIG. 9 . In this standby state, the plunger 126 waits at a standby position between the top dead center position and the bottom dead center position in the vertical direction D1, and the third rack 126c of the plunger 126 is supported by the third pin 152b to prevent the plunger 126 from falling. In the standby position, the driver blade 127 is positioned above the stopper 125 supported by the ejection unit 123 shown in FIG. 1 in the vertical direction D1. That is, the standby position of the plunger 126 in this embodiment is set at a high position near the top dead center, such that the driver blade 127 is positioned above the stopper 125. Furthermore, in the standby position, the second rack 126b of the plunger 126 does not overlap the second pin 152a in a vertical view, but overlaps the stopper pin 152c in a vertical view. 15, in the standby position, the second rack 126b of the plunger 126 does not overlap with the second pin 152a when viewed in the up-down direction, and overlaps with the stopper pin 152c at the S1 portion. As a result, if the third pin 152b is broken or the like and the plunger 126 falls in the standby state, the stopper pin 152c engages with the second rack 126b of the plunger 126, and the descent of the plunger 126 can be stopped.

[0035] When an operator performs a driving operation using the driving tool 100 described above, the operator presses the tip of the injection part 123 shown in Fig. 1 against the mating workpiece W1, and when the controller detects that the trigger switch 143 is turned on, the controller supplies power to the electric motor 114, causing the motor shaft 146 to rotate forward. The rotational force of the motor shaft 146 is amplified by a reducer (not shown) and transmitted to the first gear 151, causing the first gear 151 shown in Fig. 9 to rotate counterclockwise (rotation direction R1).

[0036] When the first gear 151 rotates counterclockwise, the second gear 152 rotates clockwise (rotational direction R2), and the third gear 153 rotates counterclockwise (rotational direction R3). When the third gear 153 rotates counterclockwise, the plunger 126 operates in the return direction D3 against the biasing force of the spring 136 shown in FIG. 1. That is, as shown in FIG. 10, the plunger 126 rises. At this time, the third pin 152b engages with the third rack 126c provided on the plunger 126 and pushes up the plunger 126, but the stopper pin 152c cannot engage with the third rack 126c. That is, as shown in FIG. 14, the stopper pin 152c is short and therefore does not engage with the third rack 126c.

[0037] On the other hand, when the third gear 153 rotates counterclockwise, the counterweight 118 operates in the impact direction D2. That is, the counterweight 118 descends.

[0038] When the counterweight 118 descends, the plunger 126 ascends. Next, the counterweight 118 reaches its bottom dead center, and the plunger 126 ascends further, and then reaches its top dead center. This results in the energy of the spring 136 being stored to its maximum.

[0039] After the plunger 126 reaches the top dead center, the third rack 126c and the third pin 152b disengage, releasing the third rack 126c and the spring 136. When the spring 136 is released, the plunger 126 descends due to the biasing force of the spring 136. When the plunger 126 begins to descend, the counterweight 118 begins to rise due to the biasing force of the spring 136.

[0040] When the plunger 126 descends, that is, when the striking portion 112 descends and reaches the bottom dead center position shown in FIG. 6, the driver blade 127 strikes the stopper 125 located in the injection path 124 shown in FIG. 1. As a result, the stopper 125 is driven into the mating material W1. After the driver blade 127 strikes the stopper 125, the plunger 126 collides with the plunger bumper 138. The plunger bumper 138 absorbs part of the kinetic energy of the striking portion 112. In addition, the counterweight 118 collides with the weight bumper 137. The weight bumper 137 absorbs part of the kinetic energy of the counterweight 118.

[0041] In this way, when the striking portion 112 operates in striking direction D2 to strike the stopper 125, the counterweight 118 operates in the return direction D3, which is opposite to the striking direction D2. This reduces the recoil generated when the striking portion 112 strikes the stopper 125.

[0042] After striking portion 112 strikes stopper 125, first gear 151 rotates counterclockwise (rotation direction R1) as shown in FIG. 7, causing first rack 126a to be wound up by first pin 151a, and plunger 126 to rise. That is, plunger 126 operates in return direction D3. As plunger 126 rises, second gear 152 further rotates clockwise (rotation direction R2), and as shown in FIG. 12, second rack 126b is supported by second pin 152a, and then plunger 126 is pushed up as shown in FIG. 8. Thereafter, pushed-up plunger 126 enters a standby state at the standby position as shown in FIG. 9. When the second pin 152a shown in FIG. 12 is pushing up the plunger 126, if the second pin 152a is damaged or the plunger 126 falls, the stopper pin 152c engages with the second rack 126b of the plunger 126 to stop the plunger 126 from descending.

[0043] As described above, the stopper pin 152c is a short pin, and therefore does not engage with the first rack 126a or the third rack 126c during the winding operation of the plunger 126 shown in Figures 6 to 10 (the operation of moving the striking part 112 upward in the vertical direction D1). Furthermore, the stopper pin 152c is arranged so that it does not engage with the second rack 126b during the normal winding operation. Therefore, the winding operation of the plunger 126 shown in Figures 6 to 10 is not hindered by the stopper pin 152c.

[0044] In the driving tool 100 of this embodiment, the second gear 152 is provided with a stopper pin 152c having a short length (small protrusion). Therefore, when the third pin 152b breaks or otherwise causes the plunger 126 to fall while the plunger 126 is in its standby position, the stopper pin 152c engages with the second rack 126b of the plunger 126, thereby stopping the plunger 126 from descending. Alternatively, when the second pin 152a is pushing up the plunger 126 and the second pin 152a breaks or otherwise causes the plunger 126 to fall, the stopper pin 152c engages with the second rack 126b of the plunger 126, thereby stopping the plunger 126 from descending. This prevents the plunger 126 from accidentally moving to the bottom dead center (BDC). Since the occurrence of a blank strike can lead to damage to the plunger 126, preventing the occurrence of a blank strike can improve the durability of the driving tool 100.

[0045] Furthermore, even if the plunger 126 falls when it is in its standby position, the descent of the plunger 126 can be stopped by the stopper pin 152c, making it possible to set the standby position of the plunger 126 at a high position close to the top dead center. This reduces the time it takes for the plunger 126 to reach the top dead center from the standby position when the operator operates the trigger 142, thereby improving the response of the driving tool 100 when the operator operates the trigger 142.

[0046] Furthermore, the stopper pin 152c and the second pin 152a are pins of the same shape and the same length (amount of protrusion). By providing the stopper pin 152c on the second gear 152, it is possible to share the gear and the pin. In other words, it is possible to share parts.

[0047] Next, a modification of this embodiment will be described.

[0048] The modified example shown in FIG. 16 illustrates a modified structure of the second gear 152 (wheel 150). Specifically, an arc-shaped protrusion 152d is provided as a second engagement portion between the second pin 152a and the third pin 152b of the second gear 152. The arc-shaped protrusion 152d can be formed integrally with the second gear 152. Even when using a second gear 152 provided with such an arc-shaped protrusion 152d, the durability of the driving tool 100 can be improved, and the response of the driving tool 100 can also be improved. Furthermore, because the arc-shaped protrusion 152d can be formed integrally with the second gear 152, the number of parts can be reduced compared to when a stopper pin 152c is provided on the second gear 152 as a second engagement portion.

[0049] If second pin 152a and protrusion 152d were formed as a continuous series of protrusions, fatigue would accumulate and durability would be reduced as the protrusions are used to wind up plunger 126. In order to ensure sufficient strength to absorb the impact when plunger 126 is dropped, it is better to form second pin 152a and protrusion 152d at a distance from each other so that they protrude independently, rather than as a series of protrusions protruding from second gear 152.

[0050] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention. For example, although the above-described embodiment has been described with reference to a coil spring type driving tool 100, the driving tool 100 may be a gas spring type that uses compressed air to lower the striking part. [Explanation of symbols]

[0051] 100... driving machine (work machine), 111... housing, 112... striking part, 113... magazine, 114... electric motor (drive source), 115... transmission mechanism, 116... control part, 117... battery pack, 118... counterweight, 119... body part, 120... handle, 121... motor case, 122... mounting part, 123... injection part, 124... injection path, 125... stopper, 126... plunger, 126a... first rack, 126b... second rack (first engaged part), 126c... third rack (second engaged part), 127... driver blade, 128... guide shaft, 129... top cover, 130... bottom holder, 131... guide bar, 132... latch, 136... spring (attached a first engagement portion, a second engagement portion, a third engagement portion, a fourth engagement portion, a fifth engagement portion, a fifth engagement portion, a fifth engagement portion, a fifth engagement portion, a fifth engagement portion, a sixth ...

Claims

1. A driving source; a striking portion that can strike the stopper by moving to one side in a first direction; a biasing portion that biases the striking portion toward one side in the first direction; a rotating unit that rotates by the driving force of the driving source to move the striking unit toward the other side in the first direction; Equipped with the rotating portion includes a base portion and a plurality of engaging portions provided on the base portion to be engageable with the striking portion; The plurality of engagement portions are a first engagement portion that engages with the hitting portion when the hitting portion is moved to the other side in the first direction; a second engaging portion that does not engage with the striking portion when the striking portion is moved to the other side in the first direction.

2. The work machine according to claim 1 , wherein the second engagement portion engages with the impact portion when the engagement between the first engagement portion and the impact portion is released and the impact portion moves to one side in the first direction.

3. An operation unit operated by an operator is provided, the first engagement portion includes a first protrusion and a second protrusion different from the first protrusion, The work machine according to claim 2 , wherein the striking portion engages with the first protrusion in a standby state in which the operating portion is not operated.

4. The work machine according to claim 3 , wherein the standby position at which the impact unit is placed in the standby state is between a top dead center position and a bottom dead center position of the impact unit in the first direction of movement.

5. an ejection portion that supports the fastener to be struck by the striking portion; The work machine according to claim 4 , wherein the striking portion, at the standby position, is located on the other side in the first direction of the stopper supported by the ejecting portion.

6. the striking portion has a first engaged portion that engages with the second protruding portion, The work machine according to claim 4 or 5, wherein, in the standby position, the first engaged portion does not overlap with the second protruding portion when viewed in a first direction, but overlaps with the second engaging portion when viewed in the first direction.

7. the first protrusion engages with a second engaged portion provided on the striking portion when the striking portion is moved to the other side in the first direction; The work machine according to claim 6 , wherein the second engaging portion is unable to engage with the second engaged portion.

8. The work machine according to claim 3 , wherein the second engagement portion is disposed rearward of the second protrusion portion in the rotation direction of the rotating portion.

9. The work machine according to claim 3 , wherein the second engaging portion and the second protruding portion are made of members having the same shape.

10. A driving source; a striking portion that can strike the stopper by moving to one side in a first direction; a biasing portion that biases the striking portion toward one side in the first direction; a rotating unit that rotates by the driving force of the driving source to move the striking unit toward the other side in the first direction; Equipped with the rotating portion includes a base portion, and a first engaging portion and a second engaging portion provided on the base portion to be engageable with the striking portion; the rotating portion rotates while the first engaging portion and the impact portion are engaged with each other, thereby moving the impact portion to a top dead center position, and after the impact portion reaches the top dead center position, disengages the first engaging portion from the impact portion, thereby causing the impact portion to strike the stopper; A work machine in which the second engagement portion engages with the impact portion when, after the first engagement portion and the impact portion engage with each other, the engagement between the first engagement portion and the impact portion is released before the impact portion reaches the top dead center position.

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