Driving tool

Abstract

To provide a driving tool which inexpensively provides an idling strike prevention mechanism that is operated when no more driven member is left.SOLUTION: A driving tool 1 includes a driver 15 moving along a driving passage 3, and a lift mechanism 22 for moving the driver 15. The driving tool 1 includes: a pusher 31 that supplies a driven member 40 from a side opposite to a first end surface 10a of a tool main body such that the driven member 40 contacts a tip end 15d of the driver 15 at a standby position; and an idling strike prevention mechanism 32 interlocking with a position of the pusher 31. When the driver 15 moves from the standby position to a top dead center, the pusher 31 supplies the driven member 40 to the driving passage 3, and then the driver 15 moves to a driving position to strike the driven member 40. When no driven member 40 is left, the idling strike prevention mechanism 32 restricts activation of the driving tool 1 by interlocking with the pusher 31 such that the pusher 31 moves to an activation restriction position on a side of the driving passage 3.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a driving tool for driving a driving tool such as a nail or staple into wood or the like. [Background technology]

[0002] Patent Document 1 discloses an air-powered driving tool that uses the gas pressure of supplied compressed air as a thrust to eject a driving tool. A driver that strikes the driving tool is connected to a piston that is movable within a cylinder. Compressed air is supplied to an upper chamber of the piston. The gas pressure of the compressed air is used to move the driver downward together with the piston. The driving tool struck by the driver is ejected from an ejection port and driven into the material to be driven. Patent Document 2 discloses a driving tool that converts the rotational drive of an electric motor into linear motion of a driver, and the driver ejects the driving tool.

[0003] The driving tool is provided with a magazine that contains a plurality of driving tools. The driving tools are sequentially supplied from the magazine to the driving passage through which the driver moves with each driving operation. When the number of driving tools remaining in the magazine is less than a predetermined number, for example, when there are none, the driving tools are not supplied to the driving passage. If the driver continues to move down the driving passage in this state, the driver will directly strike the material to be driven, resulting in a blank striking state, which will damage the material. In addition, the piston will collide with the cushion that suppresses the momentum of the piston moving downward, at maximum load. This shortens the life of the cushion. As described in Patent Documents 1 and 2, a driving tool equipped with a blank striking prevention mechanism that prevents the driver from blank striking when the number of driving tools in the magazine is less than a predetermined number has been devised.

[0004] For example, if the blank-strike prevention mechanism is activated when there are no driving tools remaining in the magazine, the previous driving tool will not be left behind in the magazine when the next driving tool is loaded into the magazine. This makes the task of loading driving tools easier. For this reason, there is a demand for driving tools equipped with a blank-strike prevention mechanism that operates when there are no driving tools remaining.

[0005] However, the blank-strike prevention mechanism, which operates when there are no driving tools remaining, must be turned off when there is only one tool remaining, and must be reliably turned on when there are no tools remaining. This requires the blank-strike prevention mechanism to be switched on and off with high precision. For example, it is possible to electrically control the mechanism by providing a switch that outputs a detection signal for the number of driving tools remaining, or to provide a blank-strike prevention mechanism with high dimensional precision. However, it is difficult to keep manufacturing costs down, which makes the product expensive. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 4181488 [Patent Document 2] Patent No. 5548100 Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, there is a need for a driving tool that can be provided with an inexpensive anti-empty drive mechanism that prevents the driver from hitting the driver empty, and that operates when there are no more driving tools remaining. [Means for solving the problem]

[0008] According to one feature of the present disclosure, the driving tool has a driving passage extending along a first end surface of the tool body. The driving tool has a driver that moves along the driving passage. The driving tool has a lift mechanism that moves the driver from the bottom dead center to a standby position and from the standby position to the top dead center. The driving tool has a pusher that supplies a driving tool from the opposite side of the first end surface so that the driving tool hits the tip of the driver in the standby position. The driving tool has an empty-strike prevention mechanism that is linked to the position of the pusher. When the driver moves from the standby position to the top dead center, the pusher supplies the driving tool to the driving passage, and the driver moves to the driving position to strike the driving tool. The empty-strike prevention mechanism is linked to the pusher to restrict the activation of the driving tool by moving the pusher to an activation restriction position on the driving passage side when the driving tool runs out.

[0009] Therefore, when there is one or more driving tools remaining, the driving tool closest to the driving passage abuts against the tip of the driver at the standby position and is restricted from entering the driving passage. When the driver moves from the standby position to the top dead center, the driving tool can enter the driving passage. When there are no driving tools remaining, the pusher moves to the start restriction position in the driving passage when the driver moves to the standby position. When the pusher moves to the start restriction position, the blank strike prevention mechanism is turned on and the start of the driving tool is restricted. Therefore, the pusher moves a distance longer than the thickness of one driving tool from the position immediately before the last driving tool is supplied to the driving passage to the start restriction position. The blank strike prevention mechanism is switched from the off state to the on state while the pusher moves this moving distance. Therefore, the blank strike prevention mechanism can be operated when there are no driving tools remaining without providing a complex structure or a structure with higher precision than necessary. This makes it possible to reduce the manufacturing cost of the blank strike prevention mechanism. In this disclosure, starting the driving tool includes all operations necessary for the driving tool to eject the driving tool, such as supplying power, pulling the trigger, starting the electric motor, starting the lift mechanism, moving the driver, and moving the contact arm. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a right side view of the driving tool according to the first embodiment of the present disclosure. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a longitudinal cross-sectional view of the driving tool with the driver in a standby position just before the last driving tool is loaded into the driving channel; [Figure 4] FIG. 11 is a vertical cross-sectional view of the driving tool with the blank-strike prevention mechanism in an on state. [Diagram 5] 4 is a cross-sectional view taken along line VV in FIG. 3. [Figure 6] 6 is a cross-sectional view taken along line VI-VI in FIG. 4. [Figure 7] FIG. 2 is a perspective view of a driver, a lift mechanism, and a magazine. [Figure 8] This is a left view of the blank strike prevention mechanism and contact arm. [Figure 9] FIG. [Figure 10] FIG. 13 is a cross-sectional view showing a comparative example of a conventional driving tool, and is a vertical cross-sectional view showing a state in which a driver is located at a standby position. [Figure 11] FIG. 11 is a right side view of a driving tool according to a second embodiment of the present disclosure. [Figure 12] FIG. [Figure 13] FIG. 2 is a longitudinal cross-sectional view of the driving tool with the driver in a standby position just before the last driving tool is loaded into the driving channel; [Figure 14] FIG. 11 is a vertical cross-sectional view of the driving tool with the blank-strike prevention mechanism in an on state. [Figure 15] 14 is a cross-sectional view taken along line XV-XV in FIG. 13. [Figure 16] 16 is a cross-sectional view taken along line XVI-XVI in FIG. 14. [Figure 17] 17 is a cross-sectional view taken along line XVII-XVII in FIG. 16. [Figure 18] FIG. [Figure 19]FIG. [Figure 20] FIG. 13 is a cross-sectional view showing a comparative example of a conventional driving tool, and is a vertical cross-sectional view showing a state in which a driver is located at a standby position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] According to another feature of the present disclosure, the pusher has an escape portion recessed in a direction away from the first end face so as to avoid contact with the tip of the driver in the standby position. Therefore, when the driver is in the standby position, the driving tool cannot enter the driving passage by abutting against the tip of the driver. On the other hand, by providing the escape portion, the pusher can move to the start restriction position S and enter the driving passage. Therefore, the pusher moves a large amount in the feed direction toward the driving passage only when there are no driving tools remaining. This allows the blank driving prevention mechanism to be provided with a simple structure that reliably operates when there are no driving tools remaining.

[0012] According to another feature of the present disclosure, the pusher is in contact with the first wall surface of the driving passage located on the first end face side and is positioned at the start restriction position. Therefore, when the number of remaining driving tools decreases from one to zero, the pusher moves by a movement amount that is the sum of the thickness of the last driving tool and the length that the pusher has advanced into the driving passage at the start restriction position. Therefore, when the blank-strike prevention mechanism is changed from the OFF state to the ON state, there is a margin in the movement distance of the pusher that is approximately the thickness of two driving tools. Therefore, the blank-strike prevention mechanism can be reliably operated. In addition, the start restriction position of the pusher can be easily set without providing a new structure. Therefore, the blank-strike prevention mechanism can be provided inexpensively with a simple structure.

[0013] According to another feature of the present disclosure, the blank-strike prevention mechanism has a contact arm that is movably attached to the tool body and that allows the lift mechanism to operate by abutting against the material to be driven and moving to the ON position. The blank-strike prevention mechanism has a stopper that engages with the contact arm when the pusher moves to the start-restricting position to restrict the movement of the contact arm to the ON position. Therefore, by providing a stopper that mechanically engages with the contact arm, the movement of the contact arm to the ON position can be restricted. Therefore, when the remaining number of driving tools becomes zero and the pusher moves to the start-restricting position, the movement of the contact arm to the ON position can be more reliably restricted. Moreover, by providing the stopper with a simple structure, the manufacturing cost can be kept low.

[0014] According to another feature of the present disclosure, the stopper engages with the contact arm before the pusher abuts against the first wall surface of the driving passage provided on the first end face side. Therefore, when the number of remaining driving tools decreases from one to zero, the pusher moves by a movement amount that is a combination of the thickness of the last driving tool and the length of the pusher that has entered the driving passage at the start restriction position. Therefore, when the stopper engages with the contact arm to change the blank-strike prevention mechanism from the OFF state to the ON state, the movement distance of the pusher has a margin that exceeds the thickness of one driving tool. Therefore, the blank-strike prevention mechanism can be reliably operated. Moreover, the blank-strike prevention mechanism can be operated before the pusher abuts against the first wall surface of the driving passage. Therefore, it is possible to prevent the pusher from accidentally pressing against the first wall surface of the driving passage and damaging it.

[0015] According to another feature of the present disclosure, the stopper is movable relative to the pusher. Therefore, when the last driving tool is supplied to the driving passage and the stopper engages with the contact arm, the pusher can move relative to the stopper, whose movement is restricted. Therefore, the pusher can move so as to continue to press the last driving tool supplied to the driving passage. This allows the last driving tool to be ejected in a stable position, and prevents nail clogging.

[0016] According to another feature of the present disclosure, the stopper has an engagement portion that engages with the contact arm. The stopper is movable relative to the pusher in the feed direction in which the pusher moves toward the first end face. The blank strike prevention mechanism is provided with a biasing member that biases the stopper in the feed direction. Therefore, even when the movement of the pusher in the feed direction is restricted, the engagement portion of the stopper is biased in the feed direction and can engage with the contact arm. Therefore, it is possible to more reliably restrict the contact arm from moving to the ON position when there are no driving tools remaining.

[0017] According to another feature of the present disclosure, the driving tool has a piston connected to the driver and moving the driver to the bottom dead center by gas pressure. Therefore, the driver is moved in the counter-driving direction by the lift mechanism, and moves in the driving direction by the gas pressure increased by the movement of the driver in the counter-driving direction. A so-called gas spring type driving tool having such a structure can be provided with a blank driving prevention mechanism that operates when there are no driving tools remaining. Therefore, in the unlikely event that there are no driving tools remaining, the driver in the standby position is ejected in the driving direction by gas pressure, which causes blank driving.

[0018] Next, an embodiment of the present disclosure will be described with reference to Figs. 1 to 9. As an example of the driving tool 1, a gas spring type driving tool that utilizes gas pressure in a pressure accumulator as a thrust for driving a driving tool is shown. In the following description, the driving direction of the driving tool is the downward direction, and the opposite driving direction is the upward direction. A user of the driving tool 1 is generally located on the left side of the driving tool 1 in Fig. 1. The side in front of the user is the rear direction, and the back side opposite the front side is the front direction. The left and right directions are based on the user.

[0019] As shown in Figures 1 and 3, the driving tool 1 has a tool body 10. The tool body 10 has a configuration in which a cylinder 12 is accommodated in a roughly cylindrical main body housing 11. A piston 14 is accommodated in the cylinder 12 so as to be capable of vertical reciprocating motion. An upper portion of the cylinder 12 located above the piston 14 is connected to a pressure accumulator chamber 13. A compressed gas, such as air, is sealed in the pressure accumulator chamber 13. The gas pressure in the pressure accumulator chamber 13 acts as a thrust that urges the upper surface of the piston 14 downward.

[0020] As shown in FIG. 3, a driving nose 2 having a driving passage 3 is provided at the bottom of the tool body 10. The driving passage 3 extends in the vertical direction along a first end face 10a corresponding to the front face of the tool body 10. The driving passage 3 is connected to the bottom of the cylinder 12. The driving nose 2 is coupled to a magazine 30 in which driving tools 40 are loaded. The magazine 30 can accommodate a plurality of driving tools 40 extending in the vertical direction and arranged side by side in the front-rear direction. The driving tools 40 are bonded to each other while lined up in the front-rear direction. The driving tools 40 are supplied one by one from the magazine 30 forward toward the driving passage 3.

[0021] 1 and 8, the driving nose portion 2 is provided with a contact arm 4 that can slide up and down. The contact arm 4 is biased toward a downward OFF position C1. When the contact arm 4 comes into contact with the workpiece W to be driven, it moves upward against the biasing force to an ON position C2.

[0022] As shown in Figures 1 and 3, a grip 5 that is held by the user is provided at the rear of the tool body 10. A trigger 6 that is operated by the user by pulling it with a fingertip is provided on the underside of the front of the grip 5. A trigger switch 6a that switches from an OFF state to an ON state in response to pulling the trigger 6 is provided inside the grip 5. When the contact arm 4 is pressed against the workpiece and moves to the ON position C2 (see Figure 8), pulling the trigger 6 becomes effective.

[0023] As shown in Fig. 3, a battery attachment section 7 extending in the vertical direction is provided on the rear surface of the grip 5. A battery pack 8 can be removably attached to the battery attachment section 7. The battery pack 8 can be removed from the battery attachment section 7 and repeatedly charged and used with a separately prepared charger. The battery pack 8 can be used as a power source for other power tools. The battery pack 8 operates as a power source that supplies power to an electric motor 20, which will be described later, and the like.

[0024] As shown in Figs. 1 and 3, the main housing 11 is provided with a substantially cylindrical drive unit case 11a extending in the front-rear direction above the magazine 30, and a connecting portion 11b that vertically connects the drive unit case 11a and the battery attachment portion 7. The grip 5, the battery attachment portion 7, the connecting portion 11b, and the drive unit case 11a cooperate to form a loop shape. The connecting portion 11b is provided with a controller 9 housed in a shallow rectangular box-shaped case. The controller 9 is housed in the connecting portion 11b in a position that extends substantially in the vertical direction. The controller 9 mainly controls the driving of the electric motor 20.

[0025] As shown in FIG. 3, a driver 15 that is long vertically is connected to the lower surface of the piston 14. The driver 15 has a main body 15a connected to the piston 14 and a striking part 15c connected to the lower part of the main body 15a. The striking part 15c extends vertically behind the main body 15a and parallel to the main body 15a. That is, the driver 15 is provided with a two-stage structure consisting of the main body 15a and the striking part 15c. The lower part of the striking part 15c enters the driving passage 3. The driver 15 moves downward by the gas pressure of the pressure accumulator 13 acting on the upper surface of the piston 14. The tip 15d located at the lower end of the striking part 15c strikes one driving tool 40 supplied to the driving passage 3 when the driver 15 moves to the driving position. The struck driving tool 40 is ejected from the ejection port 3a that opens at the lower end of the driving passage 3. The ejected driving tool 40 is driven into the material W to be driven. A cushion 16 is disposed below the cylinder 12 to absorb the shock caused when the piston 14 reaches its bottom dead center.

[0026] As shown in Fig. 7, a plurality of rack teeth (engaged portions) 15b protruding to the right are provided on the right side of the body portion 15a of the driver 15. In this embodiment, six rack teeth 15b are arranged side by side in the longitudinal direction (up-down direction) of the body portion 15a. Each rack tooth 15b is provided in a substantially triangular shape with its bottom facing the driving direction (downward). The bottom of the rack tooth 15b engages with an engagement portion 24 of the lift mechanism 22, which will be described later.

[0027] As shown in Figs. 1 and 3, the drive unit case 11a accommodates an electric motor 20 as a drive source. The electric motor 20 is accommodated in a position in which the motor axis extends in the front-rear direction. The electric motor 20 is powered by the power of the battery pack 8 and is started by pulling the trigger 6. A planetary reduction mechanism 21 is provided in front of the electric motor 20. The planetary reduction mechanism 21 uses a three-row planetary gear train. A lift mechanism 22 that moves the driver 15 upward is provided in front of the planetary reduction mechanism 21. The electric motor 20, the planetary reduction mechanism 21, and the lift mechanism 22 are arranged side by side on the motor axis. The rotational drive of the electric motor 20 is reduced in speed by the planetary reduction mechanism 21 and transmitted to the lift mechanism 22.

[0028] As shown in Figs. 1 and 7, the lift mechanism 22 is provided on the right side of the driving nose 2. The lift mechanism 22 has a wheel 23 that can rotate around an axis extending in the front-rear direction. The wheel 23 can rotate in a counterclockwise direction when viewed from the front, and clockwise rotation is restricted. A plurality of engagement parts 24 are attached along the outer periphery of the wheel 23. In this embodiment, for example, six engagement parts 24 are provided. A cylindrical shaft member (pin) extending in the front-rear direction is used for the engagement parts 24. The left part of the wheel 23 enters the driving passage 3 through a window part provided in the right part of the driving passage 3. Each engagement part 24 of the wheel 23 engages with the bottom part of the rack teeth 15b of the driver 15 in the driving passage 3. With at least one of the engagement parts 24 engaged with the bottom part of the rack teeth 15b, the wheel 23 rotates in the counterclockwise direction. This causes the driver 15 and the piston 14 to return upward. As the piston 14 is returned upward by the lift mechanism 22, the gas pressure in the pressure accumulator chamber 13 (see FIG. 3) is increased.

[0029] As shown in Figs. 2, 5 and 8, the contact arm 4 is provided as a plate-like member extending generally in the vertical direction. A tip 4a that abuts against the workpiece W is provided at the lower end of the contact arm 4. The contact arm 4 has an engaged portion 4b that engages with a stopper 33 (described later) at the left side of the magazine 30. The engaged portion 4b opens toward the rear and right and is provided in a U-shaped groove shape when viewed from the left and right direction. The stopper 33 engages with the underside of the engaged portion 4b (the front side in the figure) that is not visible in the figure. The contact arm 4 is connected to an adjustment dial 4c above the engaged portion 4b. The vertical protrusion amount of the tip 4a of the contact arm 4 can be adjusted by rotating the adjustment dial 4c.

[0030] As shown in FIG. 8, the contact arm 4 has a switch abutment 4e that extends in the front-rear direction above the adjustment dial 4c. The contact arm 4 is biased downward by a compression spring 4d provided above the switch abutment 4e. A switch 4g that can be pressed is provided above the tip of the switch abutment 4e. A leaf spring 4f is provided between the switch abutment 4e and the switch 4g. When the tip 4a of the contact arm 4 is pressed against the workpiece W, the contact arm 4 moves from the OFF position C1 to the ON position C2 against the biasing force of the compression spring 4d. The switch abutment 4e also moves from the OFF position C1 to the ON position C2 and presses the switch 4g via the leaf spring 4f. When the switch 4g is pressed to the ON state, the pulling operation of the trigger 6 (see FIG. 2) is effective. When the switch abutment 4e is located at the OFF position C1 and the switch 4g is not pressed to the OFF state, the pulling operation of the trigger 6 is not effective.

[0031] 1, 3, and 5, the magazine 30 is provided in a generally rectangular box shape extending rearward from the driving nose portion 2. The magazine 30 has a magazine body 30a capable of accommodating a plurality of driving tools 40, and a cover 30b covering the lower part of the magazine body 30a. A supply port 30c that opens toward the driving passage 3 in front and communicates with the driving passage 3 is provided in the front part of the magazine 30. The magazine 30 is provided with a driving tool storage section 30d that is groove-shaped and extends rearward in a straight line from the supply port 30c. A plurality of driving tools 40 and a pusher 31 that urges the driving tools 40 forward toward the driving passage 3 are accommodated inside the driving tool storage section 30d.

[0032] 7 and 9, the driving tool 40 is a U-shaped staple. The driving tool 40 has a rod-shaped base 40a extending in the left-right direction and a pair of legs 40b extending from both ends of the base 40a in a direction substantially perpendicular to the base 40a. The driving tool 40 is stored in the magazine 30 with the base 40a positioned at the top and the pair of legs 40b extending downward.

[0033] 3 and 5, the pusher 31 has a pair of left and right flat plates extending in the up-down and front-rear directions. When viewed from the front-rear direction, the pusher 31 has substantially the same U-shape as the driving tool 40. The pusher 31 is biased forward in the driving tool storage section 30d by a compression spring 31d provided at the rear. The front surface 31a of the pusher 31 biases the driving tool 40 stored in the front toward the driving passage 3. The upper end of the front surface 31a is provided with an escape section 31c that is cut out in the shape of an inclined surface that slopes upward and backward.

[0034] 5 and 6, the driving tool 1 is provided with an anti-empty strike mechanism 32. The anti-empty strike mechanism 32 operates when there are no driving tools 40 remaining inside the magazine 30, and restricts the winding up operation of the driver 15 by the lift mechanism 22. The anti-empty strike mechanism 32 is provided with a stopper 33 that restricts the upward movement of the contact arm 4. The stopper 33 is provided to the left of the driving tool storage section 30d of the magazine 30.

[0035] As shown in FIGS. 5 and 6, the stopper 33 extends in a generally straight line in the front-rear direction. The stopper 33 can rotate left and right around the axis of a rotating shaft 33a extending in the up-down direction. The rotating shaft 33a is provided slightly behind the center of the stopper 33 in the front-rear direction. The front end of the stopper 33 is provided with an engaging portion 33c that can engage with the engaged portion 4b of the contact arm 4 located in the OFF position C1 (see FIG. 8). When the engaging portion 33c engages with the engaged portion 4b, the contact arm 4 is restricted from moving upward from the OFF position C1 to the ON position C2 (see FIG. 8). The stopper 33 has an abutting portion 33b that protrudes to the right behind the rotating shaft 33a. The abutting portion 33b is provided in a semicircular shape when viewed in the up-down direction. The abutting portion 33b can enter the driving tool accommodating portion 30d from the left side of the driving tool accommodating portion 30d.

[0036] 5 and 6, a compression spring (biasing member) 34 is provided behind the rotating shaft 33a and to the left of the abutment portion 33b. The compression spring 34 biases the stopper 33 to rotate clockwise when viewed from below. The abutment portion 33b of the stopper 33 is biased rightward by the compression spring 34 so as to approach the pusher 31 in the driving tool accommodating portion 30d. The engagement portion 33c of the stopper 33 is biased leftward by the compression spring 34 so as to move away from the pusher 31 in the driving tool accommodating portion 30d and approach the engaged portion 4b of the contact arm 4.

[0037] 5, when one or more driving tools 40 remain in the driving tool storage section 30d, the abutment portion 33b abuts against the left side surface 31b of the pusher 31 or the leg portion 40b of the driving tool 40. This restricts the rotation of the stopper 33, and the engagement portion 33c is not engaged with the engaged portion 4b of the contact arm 4. This allows the contact arm 4 to move from the OFF position C1 to the ON position C2 (see FIG. 8).

[0038] As shown in FIG. 6, when there are no driving tools 40 remaining in the driving tool storage section 30d, the pusher 31 moves forward to a start restriction position S where it abuts against the first wall surface 3b of the driving passage 3. The first wall surface 3b extends vertically at the front side of the driving passage 3. The pusher 31 moves forward of the abutment portion 33b. Therefore, the abutment portion 33b enters the driving tool storage section 30d without abutting against the side surface 31b of the pusher 31. As a result, the stopper 33 is biased by the compression spring 34 to rotate. The engagement portion 33c moves leftward and engages with the engaged portion 4b of the contact arm 4. Therefore, the contact arm 4 cannot move from the OFF position C1 (see FIG. 8).

[0039] Next, a series of steps of the driving operation of the driving tool 1 will be described with reference to Figs. 3 to 7. Figs. 3 to 7 show the driver 15 in a standby state. The driver 15 in the standby state is held in a stopped state at a standby position slightly below the top dead center. When the driver 15 is in the standby position, the tip 15d of the striking part 15c overlaps the base 40a of the driving tool 40 in the magazine 30 in the vertical direction. Therefore, the base 40a of the driving tool 40 at the forefront located at the supply port 30c abuts against the rear surface of the tip 15d. The driving tool 40, which is pushed forward by the pusher 31, cannot enter the driving passage 3 and is stopped at the front end of the supply port 30c. At this time, a clearance K of approximately the same length as the thickness of two driving tools 40 stacked in front and behind is generated between the first wall surface 3b of the driving passage 3 and the front surface 31a of the pusher 31.

[0040] In the standby state, the contact arm 4 moves upward and the trigger 6 is pulled, thereby starting the electric motor 20. When the electric motor 20 is started, the wheel 23 of the lift mechanism 22 rotates. The engagement portion 24 engaged with the bottom surface of the lowest rack tooth 15b moves the lowest rack tooth 15b upward as the wheel 23 rotates. This causes the driver 15 to move upward from the standby position to the top dead center. When the driver 15 moves to the top dead center, the driving tool 40 is biased by the pusher 31 and becomes capable of entering the driving passage 3. As a result, one driving tool 40 at the front end is supplied from the magazine 30 into the driving passage 3.

[0041] When the driver 15 reaches the top dead center and is about to be driven in, the engaging portion 24 leaves the bottom of the lowest rack tooth 15b. This causes the driver 15 to move downward by the gas pressure in the pressure accumulator chamber 13 that has been applied to the piston 14. The striking portion 15c of the driver 15 moves downward within the driving passage 3 to the driving position, and the tip 15d strikes the base 40a of one of the driving tools 40. As the driver 15 moves downward, all of the engaging portions 24 retreat from the driving passage 3. This prevents interference between the rack teeth 15b of the driver 15 moving downward and the engaging portions 24, ensuring a smooth driving operation.

[0042] The wheel 23 continues to rotate while the driver 15 is moving downward and even after it reaches the bottom dead center. When the driver 15 is at the bottom dead center, the wheel 23 rotates to a predetermined rotation angle, and one of the engagement parts 24 engages with the bottom of the uppermost rack tooth 15b. This starts a return operation that moves the driver 15 upward in the direction opposite to the driving direction. When one of the engagement parts 24 engages with the bottom of the lowermost rack tooth 15b, the driver 15 returns to the standby position. For example, by appropriately controlling the time from the start of the start of the electric motor 20, the electric motor 20 is stopped at the stage when the piston 14 reaches the standby position. This holds the driver 15 in the standby position. This completes the series of driving operations.

[0043] As shown in Figures 4 and 6, when the last driving tool NE (see Figure 3) is ejected and there are no driving tools 40 remaining in the magazine 30, the pusher 31 is biased by the compression spring 31 to move forward toward the driving passage 3. The tip 15d of the driver 15 overlaps in the vertical direction with the upper part of the supply port 30c of the magazine 30. Meanwhile, a relief portion 31c is provided at the upper end of the front surface 31a of the pusher 31. Therefore, the tip 15d of the driver 15 and the relief portion 31c of the pusher 31 are prevented from interfering with each other. This allows the pusher 31 to move to the start restriction position S where the front surface 31a abuts against the first wall surface 3b of the driving passage 3. That is, the pusher 31 moves forward a distance equivalent to the length of the clearance K shown in FIG. 3 during the period from the state shown in FIG. 3 immediately before the last driving tool NE is loaded into the driving passage 3 to the state shown in FIG. 4 in which no driving tools 40 remain and the driver 15 is stopped at the standby position.

[0044] As shown in FIG. 6, when the pusher 31 moves to the start restriction position S, the stopper 33 is biased by the compression spring 34 to rotate. The engaging portion 33c of the stopper 33 engages with the engaged portion 4b of the contact arm 4 in the OFF position C1 (see FIG. 8). The movement of the contact arm 4 to the ON position C2 is restricted, and the switch 4g is not pressed by the switch abutment portion 4e of the contact arm 4 (see FIG. 8). As a result, the pulling operation of the trigger 6 is not effective, and the electric motor 20 is not started (see FIG. 1). In this way, it is possible to prevent the driver 15 from firing blanks when there are no driving tools 40 remaining in the magazine 30.

[0045] As a comparison with the first embodiment of the present disclosure, an example of a driving tool 70 equipped with a conventional blank driving prevention mechanism 72 is shown in FIG. 10. The driving tool 70 has a pusher 71 that urges the driving tool 40 toward the driving passage 3 by the urging force of a compression spring 71b. The last driving tool NE is pushed forward by the front surface 71a of the pusher 71. At this time, the last driving tool NE does not interfere with the tip 15d of the driver 15 in the standby position. Therefore, the last driving tool NE is loaded into the driving passage 3 below the tip 15d of the driver 15. The clearance K between the first wall surface 3b of the driving passage 3 and the front surface 71a of the pusher 71 has only the length of the thickness of the last driving tool NE. Therefore, the clearance K in the conventional driving tool 70 is shorter than the clearance K of the driving tool 1 of the present disclosure shown in FIG. 3.

[0046] As described above, the driving tool 1 has a driving passage 3 extending along the first end surface 10a of the tool body 10 as shown in Figs. 3 to 6. The driving tool 1 has a driver 15 that moves along the driving passage 3. The driving tool 1 has a lift mechanism 22 that moves the driver 15 from the bottom dead center to the standby position and from the standby position to the top dead center. The driving tool 1 has a pusher 31 that supplies the driving tool 40 from the opposite side of the first end surface 10a so that the driving tool 40 hits the tip 15d of the driver 15 in the standby position. The driving tool 1 has an empty driving prevention mechanism 32 that is linked to the position of the pusher 31. When the driver 15 moves from the standby position to the top dead center, the pusher 31 supplies the driving tool 40 to the driving passage 3, and the driver 15 moves to the driving position to strike the driving tool 40. The blank driving prevention mechanism 32 regulates the activation of the driving tool 1 in cooperation with the pusher 31 by moving the pusher 31 to the activation regulation position S on the driving passage 3 side when the driving tool 40 runs out.

[0047] Therefore, when there is one or more driving tools 40 remaining, the driving tool 40 closest to the driving passage 3 comes into contact with the tip 15d of the driver 15 at the standby position, and is restricted from entering the driving passage 3. When the driver 15 moves from the standby position to the top dead center, the driving tool 40 can enter the driving passage 3. When there are no driving tools 40 remaining, the pusher 31 moves to the start restriction position S in the driving passage 3 when the driver 15 moves to the standby position. When the pusher 31 moves to the start restriction position S, the blank strike prevention mechanism 32 is turned on, and the start of the driving tool 1 is restricted. Therefore, the pusher 31 moves a distance longer than the thickness of one driving tool 40 from the position immediately before the last driving tool NE is supplied to the driving passage 3 to the start restriction position S. The blank strike prevention mechanism 32 is switched from the off state to the on state while the pusher 31 moves this moving distance. Therefore, the blank-strike prevention mechanism 32 can be activated when the number of driving tools 40 remaining is zero, without providing the mechanism with a complex structure or a structure with higher accuracy than necessary. This makes it possible to reduce the manufacturing cost of the blank-strike prevention mechanism 32.

[0048] As shown in Figures 3 and 4, the pusher 31 has an escape portion 31c recessed in a direction away from the first end face 10a to avoid contact with the tip 15d of the driver 15 in the standby position. Therefore, when the driver 15 is in the standby position, the driving tool 40 comes into contact with the tip 15d of the driver 15 and cannot enter the driving passage 3. On the other hand, by providing the escape portion 31c, the pusher 31 can move to the start restriction position S and enter the driving passage 3. Therefore, the pusher 31 moves a large amount in the feed direction toward the driving passage 3 only when there are no driving tools 40 remaining. This allows the blank driving prevention mechanism 32 to be provided with a simple structure so that it can operate reliably when there are no driving tools 40 remaining.

[0049] As shown in Figs. 4 and 6, the pusher 31 is in contact with the first wall surface 3b of the driving passage 3 located on the first end surface 10a side and is located at the start restriction position S. Therefore, when the number of remaining driving tools 40 decreases from one to zero, the pusher 31 moves by a movement amount that is the sum of the thickness of the last driving tool NE and the length that the pusher 31 has advanced into the driving passage at the start restriction position (see Fig. 3). Therefore, when the blank-strike prevention mechanism 32 is changed from the OFF state to the ON state, there is a margin in the movement distance of the pusher 31 that is approximately the thickness of two driving tools 40. Therefore, the blank-strike prevention mechanism 32 can be reliably operated. In addition, the start restriction position S of the pusher 31 can be easily set without providing a new structure. Therefore, the blank-strike prevention mechanism 32 can be provided inexpensively with a simple structure.

[0050] 5 and 6, the stopper 33 is movable relative to the pusher 31. Therefore, when the last driving tool NE is supplied to the driving passage 3 and the stopper 33 engages with the contact arm 4, the pusher 31 can move relative to the stopper 33, whose movement is restricted. Therefore, the pusher 31 can move so as to continue to press the last driving tool NE supplied to the driving passage 3. This allows the last driving tool NE to be ejected in a stable position, preventing nail clogging.

[0051] As shown in FIG. 6, the blank-strike prevention mechanism 32 has a contact arm 4 that is movably attached to the tool body 10 and that allows the lift mechanism 22 to operate by abutting against the workpiece and moving to the ON position C2 (see FIG. 8). The blank-strike prevention mechanism 32 has a stopper 33 that engages with the contact arm 4 when the pusher 31 moves to the start-restricting position S to restrict the movement of the contact arm 4 to the ON position C2. Therefore, by providing the stopper 33 that mechanically engages with the contact arm 4, the movement of the contact arm 4 to the ON position C2 can be restricted. Therefore, when the remaining number of driving tools 40 becomes zero and the pusher 31 moves to the start-restricting position S, the movement of the contact arm 4 to the ON position C2 can be more reliably restricted. Moreover, by providing the stopper 33 with a simple structure, the manufacturing cost can be kept low.

[0052] As shown in Figures 3 and 4, the driving tool 1 has a piston 14 that is connected to the driver 15 and moves the driver 15 to the bottom dead center by gas pressure. Therefore, the driver 15 moves in the counter-driving direction by the lift mechanism 22, and moves in the driving direction by the gas pressure increased by the movement of the driver 15 in the counter-driving direction. The driving tool 1 having such a structure, which is called a gas spring type, can be provided with an anti-empty driving mechanism 32 that operates when there are no driving tools 40 remaining. Therefore, in the unlikely event that there are no driving tools 40 remaining, the driver 15 in the standby position is ejected in the driving direction by gas pressure, which causes an empty driving.

[0053] Next, a second embodiment of the present disclosure will be described with reference to Figs. 11 to 19. A driving tool 50 of the second embodiment has a contact arm 51 and a driver 52 instead of the contact arm 4 and the driver 15 of the driving tool 1 shown in Fig. 7. The driving tool 50 has a magazine 53, a pusher 54, and an anti-empty-strike mechanism 56 instead of the magazine 30, the pusher 31, and the anti-empty-strike mechanism 32 of the driving tool 1 shown in Fig. 5. In the following description, only the parts that differ from the first embodiment will be described in detail.

[0054] 11 and 18, the contact arm 51 is provided so as to be vertically slidable on the driving nose portion 2. The contact arm 51 is biased downward toward the OFF position. When the contact arm 51 comes into contact with the workpiece W, it moves upward against the biasing force toward the ON position.

[0055] As shown in Figs. 12, 15, and 18, the contact arm 51 is provided as a plate-like member extending generally in the vertical direction. A tip 51a that abuts against the workpiece W is provided at the lower end of the contact arm 51. The contact arm 51 has an engaged portion 51b that engages with a stopper 57 (described later) at the left side of the magazine 53. The engaged portion 51b is located on the front side not visible in Fig. 15, and is provided in a flat shape that faces upward and extends forward and backward. The contact arm 51 is connected to an adjustment dial 51c above the engaged portion 51b. By rotating the adjustment dial 51c, the amount of protrusion of the tip 51a of the contact arm 51 in the vertical direction can be adjusted.

[0056] As shown in FIG. 18, the contact arm 51 has a switch abutment 51d extending in the front-rear direction above the adjustment dial 51c. The contact arm 51 is biased downward by a compression spring (not shown) provided above the switch abutment 51d. A switch 4g (see FIG. 8) is provided above the tip of the switch abutment 51d. When the tip 51a of the contact arm 51 is pressed against the workpiece W (see FIG. 12), the contact arm 51 moves upward from the OFF position to the ON position against the biasing force of the compression spring. When the switch abutment 51d is in the OFF position, the switch 4g is not pressed and is in the OFF state. When the switch abutment 51d moves upward to the ON position, it presses the switch 4g to turn it on.

[0057] As shown in Figs. 13 and 18, the driver 52 has a vertically long main body 52a. The upper part of the main body 52a is connected to the lower surface of the piston 14. The lower part of the main body 52a enters the driving passage 3. On the right side of the main body 52a, a plurality of, for example, six rack teeth (engaged parts) 52b protruding to the right are arranged vertically. Each rack tooth 52b is arranged in a substantially triangular shape with its bottom facing downward. The bottom of the rack tooth 52b engages with the engagement part 24 of the lift mechanism 22 shown in Fig. 7. On the lower end of the main body 52a, a tip 52c is provided for striking one driving tool 60 supplied to the driving passage 3.

[0058] As shown in Figs. 11, 13, and 15, the magazine 53 is provided in the shape of a rectangular box extending rearward from the driving nose portion 2. The magazine 53 has a magazine body 53a capable of accommodating a plurality of driving tools 60. The driving tools 60 each extend vertically and are aligned in the front-rear direction and are bonded to one another. The driving tools 60 are supplied one by one forward from the magazine 53 toward the driving passage 3. A supply port 53c is provided at the front of the magazine 53, which opens toward the driving passage 3 in front and communicates with the driving passage 3. The magazine 53 is provided with a driving tool storage section 53d in the shape of a groove extending linearly rearward from the supply port 53c. A plurality of driving tools 60 and a pusher 54 that urges the driving tools 60 forward toward the driving passage 3 are accommodated inside the driving tool storage section 53d.

[0059] 18 and 19, the driving tool 60 is a nail that extends linearly. The driving tool 60 has a head 60a and legs 60b extending from the head 60a. The driving tool 60 is stored in the magazine 53 in an orientation in which the head 60a is located at the top and the legs 60b extend downward.

[0060] As shown in Figs. 13 and 15, the pusher 54 is provided on a flat plate extending in the up-down direction and in the roughly front-rear direction. The magazine 53 is provided with a pusher biasing portion 55 that biases the pusher 54 forward. The pusher biasing portion 55 is attached to the magazine body 53a so as to be slidable parallel to the extension direction of the driving tool storage portion 53d. The pusher biasing portion 55 has a winding shaft 55b that is rotatably supported on the right side of the magazine 53. A leaf spring 55a wound in a spiral shape is attached to the winding shaft 55b. One end of the leaf spring 55a is fixed to the driving nose portion 2. The leaf spring 55a elastically deforms so as to wind around the winding shaft 55b, thereby biasing the pusher biasing portion 55 forward. The rear portion of the pusher 54 is connected to the pusher biasing portion 55. Therefore, the pusher 54 is urged forward together with the pusher urging portion 55. The front surface 54a of the pusher 54 urges the driving tool 60 housed in the front toward the driving passage 3. A bent portion 54b that is bent in an L-shape toward the left is provided behind the front surface 54a. The pusher 54 is connected to the pusher urging portion 55 behind the bent portion 54b. A relief portion 54c that is cut out in a substantially rectangular shape is provided at the upper end of the front surface 54a.

[0061] 15 and 16, the driving tool 50 is provided with an anti-empty strike mechanism 56. The anti-empty strike mechanism 56 operates when there are no driving tools 60 remaining inside the magazine 53, and restricts the winding up operation of the driver 52 by the lift mechanism 22. The anti-empty strike mechanism 56 is provided with a stopper 57 that restricts the upward movement of the contact arm 51. The stopper 57 is provided to the left of the driving tool storage section 53d of the magazine 53.

[0062] 15 to 17, the stopper 57 is provided in a generally rectangular flat plate shape extending in the front-rear and up-down directions. The stopper 57 is held by a rectangular box-shaped stopper holding portion 55c provided on the pusher biasing portion 55. The stopper 57 is biased forward together with the pusher biasing portion 55. An engaging portion 57a ​​is provided at the front end of the stopper 57 and is engageable with the engaged portion 51b of the contact arm 51 positioned in the OFF position. When the engaging portion 57a ​​engages with the engaged portion 51b, the contact arm 51 is restricted from moving upward from the OFF position to the ON position.

[0063] As shown in FIG. 17, the blank-strike prevention mechanism 56 is provided with a relative movement mechanism 58 that allows the stopper 57 and the pusher 54 to move relatively in the front-rear direction. The relative movement mechanism 58 has a compression spring (biasing member) 58a that is interposed between a recess 57b on the rear surface of the stopper 57 and the stopper holding portion 55c. The stopper 57 is biased forward with respect to the stopper holding portion 55c by the compression spring 58a. The stopper 57 is capable of moving rearward with respect to the stopper holding portion 55c against the biasing force of the compression spring 58a. The stopper 57 is provided with an elongated hole 57c that penetrates in the left-right direction and is long in the front-rear direction. A cylindrical boss 55d provided on the stopper holding portion 55c is inserted into the elongated hole 57c. The stopper 57 is capable of moving in the front-rear direction by the length that the boss 55d can move relatively within the elongated hole 57c. The stopper holding portion 55c is provided integrally with the pusher 54 so as not to move relative to the pusher 54. Therefore, the pusher 54 is movable relative to the stopper 57 in the front-rear direction.

[0064] 15, when one or more driving tools 60 remain in the driving tool accommodation portion 53d, the engaging portion 57a ​​of the stopper 57 is located behind the engaged portion 51b of the contact arm 51 and is not engaged with the engaged portion 51b. Therefore, the contact arm 51 can move from the ON position to the ON position.

[0065] 16, when there are no driving tools 60 remaining in the driving tool storage portion 53d, the pusher 54 moves forward to a start restriction position S just before it comes into contact with the first wall surface 3b of the driving passage 3. At this time, the engaging portion 57a ​​of the stopper 57 moves forward to a position where it engages with the engaged portion 51b of the contact arm 51. Therefore, the contact arm 51 cannot move from the ON position.

[0066] Next, the operation of the pusher 54 and the stopper 57 in relation to the driving operation of the driving tool 50 will be described with reference to Figures 13 to 17. Figures 13 to 16 show the driver 52 in a standby state. The driver 52 in the standby state is held in a stopped state at a standby position slightly below the top dead center. When the driver 52 is in the standby position, the tip 52c of the driver 15 overlaps the head 60a of the driving tool 60 in the magazine 53 in the vertical direction. Therefore, the head 60a of the driving tool 60 at the forefront located at the supply port 53c abuts against the rear surface of the tip 52c. The driving tool 60 urged forward by the pusher 54 cannot enter the driving passage 3 and is stopped at the front end of the supply port 53c. At this time, a clearance K having a length approximately equal to the thickness of two driving tools 60 stacked front and rear is generated between the first wall surface 3b of the driving passage 3 and the front surface 54a of the pusher 54.

[0067] When the driver 52 moves from the standby position to the top dead center, the driving tool 60 is biased by the pusher 54 and becomes capable of entering the driving passage 3. As a result, one driving tool 60 at the forefront is supplied from the magazine 53 into the driving passage 3.

[0068] As shown in Figures 14 and 16, when the last driving tool NE (see Figure 13) is ejected and there are no driving tools 60 remaining in the magazine 53, the pusher 54 is urged by the pusher urging portion 55 to move forward toward the driving passage 3. The tip 52c of the driver 52 overlaps in the vertical direction with the upper part of the supply port 53c of the magazine 53. Meanwhile, a relief portion 54c is provided at the upper end of the front surface 54a of the pusher 54. Therefore, the tip 52c of the driver 52 and the relief portion 54c of the pusher 54 are prevented from interfering with each other. This allows the pusher 54 to move to the start restriction position S just before the front surface 54a comes into contact with the first wall surface 3b of the driving passage 3. In other words, the pusher 54 moves forward a distance longer than the thickness of one but less than the thickness of two driving tools 60 during the period from the state shown in FIG. 13 immediately before the last driving tool NE is loaded into the driving passage 3 to the state shown in FIG. 14 when there are no driving tools 60 remaining and the driver 52 is stopped in the standby position.

[0069] When the last nail driving tool NE is supplied into the driving passage 3, the engaging portion 57a ​​of the stopper 57 moves to a front-rear position where it can engage with the engaged portion 51b of the contact arm 51. If the engaged portion 51b of the contact arm 51 abuts against the front surface of the stopper 57 and the forward movement of the pusher 54 stops, the urging force of the pusher 54 that acts to maintain the position of the last nail driving tool NE supplied to the driving passage 3 is released. If the tip 52c of the driver 52 strikes the last nail driving tool NE, which is unstable in position, there is a risk of malfunction such as nail clogging. By making the stopper 57 and the pusher 54 relatively movable in the front-rear direction by the relative movement mechanism 58, the pusher 54 can be moved forward relative to the stopper 57 while the engaging portion 57a ​​of the stopper 57 is engaged with the engaged portion 51b of the contact arm 51. This allows the pusher 54 to maintain the urging force that presses the last nail driving tool NE against the first wall surface 3b of the driving passage 3.

[0070] As shown in Fig. 16, when the pusher 54 moves to the start restriction position S, the engaging portion 57a ​​of the stopper 57 engages with the engaged portion 51b of the contact arm 51 in the OFF position. The movement of the contact arm 51 to the ON position is restricted, and the switch 4g is not pressed by the switch abutment portion 51d of the contact arm 51 (see Figs. 8 and 17). As a result, the pulling operation of the trigger 6 is not effective, and the electric motor 20 is not started (see Fig. 11). In this way, it is possible to prevent the driver 52 from firing blank shots when there are no driving tools 60 remaining in the magazine 53.

[0071] As a comparison with the second embodiment of the present disclosure, an example of a driving tool 80 equipped with a conventional blank driving prevention mechanism 82 is shown in FIG. 20. The driving tool 80 has a pusher 81 that urges the driving tool 60 toward the driving passage 3. The last driving tool NE is pushed forward by the front surface 81a of the pusher 81. At this time, the last driving tool NE does not interfere with the tip 52c of the driver 52 in the standby position. Therefore, the last driving tool NE is loaded into the driving passage 3 below the tip 52c of the driver 52. The clearance K between the first wall surface 3b of the driving passage 3 and the front surface 81a of the pusher 81 has only the length of the thickness of the last driving tool NE. Therefore, the clearance K in the conventional driving tool 80 is shorter than the clearance K of the driving tool 50 of the present disclosure shown in FIG. 13.

[0072] As described above, the stopper 57 engages with the contact arm 51 before the pusher 54 abuts against the first wall surface 3b of the driving passage 3 provided on the first end surface 10a side, as shown in Figs. 14 and 16. Therefore, when the number of remaining driving tools 60 decreases from one to zero, the pusher 54 moves by a movement amount that is a combination of the thickness of the last driving tool NE and the length of the drive into the driving passage 3 at the start restriction position S (see Fig. 13). Therefore, when the stopper 57 engages with the contact arm 51 to change the blank-strike prevention mechanism 56 from the OFF state to the ON state, the pusher 54 has a margin of movement that exceeds the thickness of one driving tool 60. Therefore, the blank-strike prevention mechanism 56 can be reliably operated. Moreover, the blank-strike prevention mechanism 56 can be operated before the pusher 54 abuts against the first wall surface 3b of the driving passage 3. Therefore, it is possible to prevent the pusher 54 from accidentally pressing and damaging the first wall surface 3b of the driving passage 3.

[0073] 15 to 17, the stopper 57 is movable relative to the pusher 54. Therefore, when the last driving tool NE is supplied to the driving passage 3 and the stopper 57 engages with the contact arm 51, the pusher 54 can move relative to the stopper 57, whose movement is restricted. Therefore, the pusher 54 can move so as to continue to press the last driving tool NE supplied to the driving passage 3. This allows the last driving tool NE to be ejected in a stable position, preventing nail clogging.

[0074] 16 and 17, the stopper 57 has an engagement portion 57a ​​that engages with the contact arm 51. The stopper 57 is movable relative to the pusher 54 in the feed direction in which the pusher 54 moves toward the first end face 10a. The blank striking prevention mechanism 56 is provided with a compression spring (biasing member) 58a that biases the stopper 57 in the feed direction. Therefore, even when the movement of the pusher 54 in the feed direction is restricted, the engagement portion 57a ​​of the stopper 57 is biased in the feed direction and can engage with the contact arm 51. Therefore, it is possible to more reliably restrict the contact arm 51 from moving to the ON position C2 when there are no driving tools 60 remaining.

[0075] Various modifications can be made to the driving tools 1, 50 of the above-described embodiments. The driving tools 1, 50 of the gas spring type are exemplified. Instead of this, the present disclosure may be applied to a driving tool called a mechanical spring type, in which the driver is moved in the anti-driving direction by a lift mechanism and the spring force of a mechanical compression spring or the like is increased to move the driver in the driving direction. The shape, size, etc. of the driving tool are not limited to the exemplified driving tools 40, 60 and may be modified as appropriate.

[0076] The drivers 15, 52 are not limited to those illustrated, and may be modified as appropriate. For example, the number of rack teeth 15b, 52b and the vertical spacing may be modified as appropriate. The lift mechanism 22 is not limited to those illustrated, and may be modified as appropriate. For example, the number of engaging portions 24 and the circumferential spacing may be modified as appropriate. For example, instead of the pin-shaped engaging portion 24, a pinion-shaped engaging portion having multiple teeth may be used.

[0077] In the above example, the movement of the contact arm 4, 51 to the ON position is restricted to restrict the start of the driving tool 1, 50, thereby activating the blank strike prevention mechanism 32, 56. Alternatively, the blank strike prevention mechanism 32, 56 may be activated by restricting the operation of starting the driving tool 1, 50, such as the supply of power from the battery pack 8, pulling the trigger 6, starting the trigger switch 6a, starting the electric motor 20, rotating the wheel 23, and moving the driver 15, 52.

[0078] In the above example, the stopper 33 mechanically engages with the pusher 31 to detect the front-rear position of the pusher 31, and engages with the contact arm 4 when the pusher 31 moves to the activation restriction position S. Alternatively, for example, a configuration may be used in which a sensor detects that the pusher 31 moves to the activation restriction position S, and the stopper 33 engages with the contact arm 4. In the above example, the stopper 33, 57 is provided to the left of the pusher 31, 54. Alternatively, the stopper 33, 57 may be provided to the right of the pusher 31, 54.

[0079] In the above example, the pushers 31, 54 are provided with the relief portions 31c, 54c so that they do not come into contact with the drivers 15, 52 when they move to the start-restricted position S. Alternatively, the pushers 31, 54 may come into contact with the drivers 15, 52 at the relief portions 31c, 54c as long as they do not apply unnecessary pressing force to the drivers 15, 52. [Explanation of symbols]

[0080] 1...Driving tool 2…Driving nose part 3... firing passage, 3a... ejection port, 3b... first wall 4...contact arm, 4a...tip, 4b...engaged portion, 4c...adjustment dial 4d...Compression spring, 4e...Switch contact portion, 4f...Leaf spring, 4g...Switch 5. Grip 6...Trigger, 6a...Trigger switch 7…Battery mounting section 8…Battery pack 9. Controller 10...Tool body, 10a...First end surface 11...main body housing, 11a...drive unit case, 11b...connection unit 12...Cylinder 13...Accumulation chamber 14…Piston 15: driver; 15a: main body; 15b: rack teeth (engaged portion); 15c: striking portion 15d…Tip 16…Cushion 20...Electric motor 21...Planetary reduction mechanism 22...Lift mechanism 23…Wheels 24...Engagement part 30...magazine, 30a...magazine body, 30b...cover, 30c...supply port 30d…Driver storage section 31... pusher, 31a... front surface, 31b... side surface, 31c... relief portion, 31d... compression spring 32...Anti-running mechanism 33...stopper, 33a...rotating shaft, 33b...contact part, 33c...engaging part 34...Compression spring (biasing member) 40: driving tool, 40a: base, 40b: leg 50...Driving tool 51: contact arm; 51a: tip; 51b: engaged portion; 51c: adjustment dial 51d...Switch contact part 52: driver, 52a: main body, 52b: rack (engaged part), 52c: tip 53...magazine, 53a...magazine body, 53c...supply port 53d…Driver storage section 54... pusher, 54a... front surface, 54b... bending portion, 54c... relief portion 55: pusher biasing portion, 55a: leaf spring, 55b: winding shaft 55c... stopper holding portion, 55d... boss 56…Anti-empty firing mechanism 57... stopper, 57a... engagement portion, 57b... recess, 57c... long hole 58... relative movement mechanism, 58a... compression spring (biasing member) 60: driving tool, 60a: head, 60b: leg 70...Driving tool 71... pusher, 71a... front surface, 71b... compression spring 72...Anti-blanket mechanism 80...Driving tool 81...pusher, 81a...front 82...Anti-empty firing mechanism NE…(last) driving tool W…Material to be driven K…Clearance S…Start regulation position C1…OFF position, C2…ON position

Claims

1. A driving tool, a driving passage extending along the first end surface of the tool body; a driver that moves along the driving path; a lift mechanism that moves the driver from a bottom dead center to a standby position and from the standby position to a top dead center; a pusher that supplies the driving tool from the opposite side of the first end surface so that the driving tool contacts the tip of the driver at the standby position; A blank strike prevention mechanism is provided which is linked to the position of the pusher. The driver moves from the standby position to the top dead center, causing the pusher to supply the driving tool to the driving passage, and the driver moves to a driving position to strike the driving tool; The blank driving prevention mechanism restricts activation of the driving tool by moving the pusher to an activation restriction position on the driving passage side when the driving tool runs out.

2. The driving tool according to claim 1, The driving tool has a recess portion recessed in a direction away from the first end face so as to avoid contact with the tip of the driver in the standby position.

3. The driving tool according to claim 1 or 2, The pusher is a driving tool that is positioned at the activation restriction position by abutting against a first wall surface of the driving passage that is located on the first end face side.

4. The driving tool according to claim 1 or 2, The blank striking prevention mechanism includes a contact arm that is movably attached to the tool body and that allows the lift mechanism to operate by contacting the workpiece and moving to an ON position. The driving tool has a stopper that engages with the contact arm when the pusher moves to the activation restricting position to restrict movement of the contact arm to the ON position.

5. The driving tool according to claim 4, The stopper is a driving tool that engages with the contact arm before the pusher abuts against a first wall surface of the driving passage provided on the first end face side.

6. The driving tool according to claim 4, The stopper is a driving tool that is movable relative to the pusher.

7. The driving tool according to claim 6, the stopper has an engaging portion that engages with the contact arm and is movable relative to the pusher in a feed direction in which the pusher moves toward the first end surface; The driving tool, wherein the blank striking prevention mechanism is provided with a biasing member that biases the stopper in the feed direction.

8. The driving tool according to claim 1 or 2, A driving tool having a piston connected to the driver and configured to move the driver to the bottom dead center by gas pressure.

Images