Shopping tools

Abstract

To provide a driving tool capable of inhibiting twisting of a wire.SOLUTION: A driving tool 10 includes: a plunger 32 which may move in a fastener F driving direction DR1; a coil spring 36 which may expand or contract and serves as a driving source of the plunger 32; a moving member 38 which is disposed at an end part as seen in an expansion / contraction direction A of the coil spring 36 and may move in the expansion / contraction direction A of the coil spring 36; a wire 40 which connects the moving member 38 with the plunger 32 and transmits driving force of the coil spring 36 to the plunger 32 through the moving member 38; and a rotation inhibition part 100 which inhibits the moving member 38 from rotating around a center axis as seen in the expansion / contraction direction A of the coil spring 36.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a driving tool. [Background technology]

[0002] There is known a driving tool that electrically drives nails, tacks, staples, pins, etc. (hereinafter referred to as "fasteners"). The driving tool is equipped with a driver that drives out the fastener, and a plunger that holds the driver and can move in the driving direction. When driving the fastener, the plunger moves forcefully in the driving direction, which moves the driver in the driving direction and drives out the fastener. A coil spring or the like that can bias the plunger is used as a drive source for moving the plunger (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-236250 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the driving tool described above, it is necessary to transmit the driving force of the coil spring to the plunger. In this case, for example, a movable member may be disposed at one end of the coil spring in the extension direction, and the movable member and the plunger may be connected by a wire to transmit the driving force of the coil spring to the plunger.

[0005] However, in the above-mentioned case, after the coil spring reaches the maximum extension position once, it repeatedly expands and contracts finely due to its restoring force. At this time, since the speed of the expansion and contraction of the coil spring and the moving speed of the moving member are not the same, the moving member and the coil spring come into contact and separate, and at this time, the moving member tries to shift in the rotational direction relative to the end of the coil spring. As a result, it is considered that the moving member rotates relative to the coil spring, and the wire connected to the moving member is twisted. If the wire is twisted in this way, it may cause, for example, the wire to break. Furthermore, the length of the wire may be effectively shortened due to the twisting, which may cause the plunger to shift or the coil spring to be compressed more than the setting, resulting in an excessive load being applied to the coil spring.

[0006] The present invention has been made in consideration of the above-mentioned points, and has an object to provide a driving tool that can suppress twisting of a string-like member such as a wire. [Means for solving the problem]

[0007] A driving tool according to one embodiment of the present invention comprises a plunger movable in the direction in which a fastener is driven, a biasing member that is extendable and contracts and serves as a driving source for the plunger, a movable member that is arranged at an end of the biasing member in the extension / contraction direction and is movable in the extension / contraction direction of the biasing member, a string-like member that connects the movable member and the plunger and transmits the driving force of the biasing member to the plunger via the movable member, and a rotation suppression section that suppresses rotation of the movable member around the central axis in the extension / contraction direction of the biasing member.

[0008] According to the above aspect, the driving tool includes a rotation suppressing portion that suppresses rotation of the moving member relative to the biasing member, so that twisting of the string-shaped member can be suppressed.

[0009] In the above aspect, the rotation suppressing portion may have a guide portion formed along the extension / contraction direction of the biasing member, and a slider portion provided on the moving member and moving along the guide portion.

[0010] In the above aspect, the driving tool may further include a cylinder that houses the urging member, the guide portion being a hole formed in the cylinder, and the slider portion being a pin that is inserted into the hole.

[0011] In the above aspect, the driving tool may further include a guide rail that guides the plunger in the driving direction of the fastener, and the cylinder may be fixed to the guide rail.

[0012] In the above aspect, the cylinder may have a cylindrical portion and a cap portion, the cylindrical portion and the cap portion may be fitted together, and the cap portion may be fixed to the guide rail.

[0013] In the above aspect, the guide portion may be configured so that the amount of rotation of the movable member permitted to rotate in the extended position of the urging member is greater in other positions than the amount of rotation of the movable member permitted to rotate in the extended position of the urging member.

[0014] In the above aspect, the rotation suppressing portion may include a low-friction member that is disposed between the moving member and the biasing member and has a smaller friction coefficient with respect to the biasing member than the moving member.

[0015] In the above aspect, the rotation suppressing portion may include a buffer member interposed between the moving member and the biasing member.

[0016] In the above-described aspect, the plunger may be moved in the fastener ejection direction by the extension action of the urging member, and the extension direction of the urging member and the fastener ejection direction may be opposite to each other. Effect of the Invention

[0017] According to the present invention, it is possible to provide a driving tool capable of suppressing twisting of a string-shaped member. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a side view of the driving tool according to the present embodiment. [Diagram 2] 2 is a cross-sectional view of the driving tool as viewed from the side. FIG. [Diagram 3] FIG. 2 is a perspective view of a plunger assembly. [Figure 4] 1 is a cross-sectional view of the plunger assembly when viewed from the side with the coil spring contracted. FIG. [Diagram 5] 1 is a cross-sectional view of the plunger assembly from the front with the coil spring extended; FIG. [Figure 6] FIG. 2 is a cross-sectional view of the plunger assembly as viewed from above. [Figure 7] FIG. 13 is a perspective view showing a wire engaged with the plunger and the moving member. [Figure 8] FIG. 2 is a side view of a portion of the plunger assembly. [Figure 9] FIG. 4 is a cross-sectional side view of a portion of the plunger assembly. [Figure 10] FIG. 2 is a perspective view of a moving member, a low-friction member, and a cushioning member. [Figure 11] FIG. [Figure 12] FIG. 4 is an exploded view showing a part of the cylinder and the guide rail. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments are merely examples for explaining the present invention, and are not intended to limit the present invention to the embodiments.

[0020] [Configuration of driving tools] Fig. 1 shows a side view of an electric driving tool 10 (however, a partial cross-sectional view of the magazine portion is shown), and Fig. 2 shows a cross-sectional view of the driving tool 10 seen from the same direction as Fig. 1 (however, the state after all fasteners F in the magazine 14 have been driven out is shown). This driving tool 10 is an electric nail driver configured to be able to drive nails (an example of "fasteners F") by driving a plunger 32 (Fig. 2) using a motor 20 (Fig. 2).

[0021] In this specification, the terms "up and down," "front and back," and "left and right" are based on the posture of the driving tool 10 in Fig. 1 and Fig. 2. The left and right direction of the paper in Fig. 1 and Fig. 2 is the front and back direction X of the driving tool 10 (the left direction of the paper is the front direction X1 of the driving tool 10, and the right direction of the paper is the rear direction X2 of the driving tool 10), the vertical direction of the paper in Fig. 1 and Fig. 2 is the left and right direction Y of the driving tool 10, and the up and down direction of the paper in Fig. 1 and Fig. 2 is the up and down direction Z of the driving tool 10. The downward direction of the paper in Fig. 1 and Fig. 2 corresponds to the direction in which the fastener F is driven out, and therefore may be called the driving direction DR1 or the injection direction DR1, and the opposite upward direction of the paper is the direction away from the injection port 12A from which the fastener F is driven out, and therefore may be called the moving away direction DR2.

[0022] The driving tool 10 includes a housing 12, a magazine 14 that stores fasteners F driven by the driving tool 10, a driver 34 for driving out the fasteners F, a plunger 32 to which the driver 34 is attached, a motor 20 and a gear 22 for moving the plunger 32 from the bottom dead center to the top dead center, a coil spring 36 (an example of a "biasing member") that applies a driving force for moving the plunger 32 from the top dead center to the bottom dead center, a moving member 38 disposed at an end of the coil spring 36 that extends, a wire 40 (an example of a "string-like member") that engages with the plunger 32 and the moving member 38 to link them, and a pulley 42 (an example of a "direction changing member") around which the wire 40 is hung. The driving tool 10 further includes a detachable battery B.

[0023] The driving tool 10 includes a housing 12 (hereinafter, the housing 12 and a portion fixed to the housing 12 may be referred to as a "tool body") that houses the main components of the driving tool 10 including the plunger 32. The housing 12 includes a grip portion 12B for an operator to hold, a bridge portion 12C that connects a portion where the motor 20 is located to a portion where the battery B is attached, and a nose portion 12D for driving out the fastener F. The grip portion 12B is formed, for example, in a columnar shape extending in the front-rear direction X so that the operator can easily hold it. The bridge portion 12C is formed in a columnar shape extending in the front-rear direction X below the grip portion 12B. The front end of the housing 12 (and the front end of the driving tool 10) includes a nose portion 12D in which an ejection port 12A for ejecting the fastener F downward is formed. A contact arm 12D1 may be attached to the tip of the nose portion 12D. Contact arm 12D1 is provided around ejection port 12A so as to be able to protrude and retract from ejection port 12A, and functions as a safety device that permits ejection of fastener F only when contact arm 12D1 is pressed against the object to be driven and trigger 12E is pressed down.

[0024] A trigger 12E is provided on the housing 12. When a user presses the trigger 12E, it establishes electrical continuity between the battery B and the motor 20. The trigger 12E is exposed on a surface facing downward (the driving direction DR1 of the fastener F) of the grip portion 12B, and is biased downward by a trigger biasing member 12F such as a spring.

[0025] The battery B is configured to be detachably attached to the rear end of the grip portion 12B and the bridge portion 12C. The battery B functions as a DC power source that supplies power for driving a motor or the like, and is configured, for example, as a lithium ion battery capable of outputting a predetermined DC voltage (for example, 14 V to 20 V). The driving tool 10 can be portable and used by attaching the battery B. However, the battery B may be configured to be stored in the housing 12, or the power may be supplied by a means other than a battery.

[0026] Driving tool 10 includes magazine 14 attached to the rear of nose portion 12D. Magazine 14 is configured to be loaded with a plurality of linked fasteners F (FIG. 1). Magazine 14 includes pusher 14A that urges fasteners F toward nose portion 12D. Pusher 14A is urged by a urging member (not shown) so that when the leading fastener F is driven out by driver 34, the adjacent fastener F is supplied to the ejection path of nose portion 12D.

[0027] The driving tool 10 further includes a plunger assembly 30. Fig. 3 is a perspective view of the plunger assembly 30, Fig. 4 is a cross-sectional view of the plunger assembly 30 as viewed from the side with the coil spring 36 in its most contracted state, and Fig. 5 is a cross-sectional view of the plunger assembly as viewed from the front with the coil spring in its most extended state. Fig. 6 shows a cross-sectional view of the plunger assembly 30 as viewed from above. Fig. 7 is a perspective view showing the plunger 32, a pin 38A that is a part of the moving member 38, and a wire 40 that engages with the plunger 32 and the moving member 38.

[0028] As shown in Figures 4 to 7, the plunger assembly 30 includes, for example, a driver 34, a plunger 32, a coil spring 36, a moving member 38, a wire 40, a pulley 42, a cylinder 44 that houses the coil spring 36, and a pair of guide rails 46 that regulate the movement direction of the plunger 32.

[0029] The driver 34 is a member that contacts and strikes the fastener F to drive out the fastener F. For example, the driver 34 according to this embodiment is composed of a rigid metal body formed into a long, thin rod extending in the drive direction DR1 of the fastener F. Since the fastener F is disposed on an extension line of the driver 34, when the driver 34 moves in the drive direction DR1, the front end of the driver 34 strikes the fastener F. The rear end of the driver 34 is connected to the plunger 32 and is configured to move integrally with the plunger 32.

[0030] The plunger 32 is a member that moves from the top dead center to the bottom dead center, moving integrally with the driver 34 to drive out the fastener F. As shown in Fig. 7, the plunger 32 has four side walls, including a first side wall 32A with which the wire 40 engages, a second side wall 32B connected to the first side wall 32A at a substantially right angle and engaging with the guide rail 46, a third side wall 32C connected to the second side wall 32B at a substantially right angle, arranged substantially parallel to the first side wall 32A, with which the driver 34 engages, and a fourth side wall 32D connected to the third side wall 32C and the first side wall 32A at a substantially right angle, arranged substantially parallel to the second side wall 32B, and engaging with the guide rail 46. A cylinder 44, which will be described later, is disposed in a hollow area surrounded by the four side walls.

[0031] The outer wall surface of the first side wall portion 32A is provided with gear engagement portions 32A1, which are two convex portions provided at different heights. The plunger 32 is configured to move from the bottom dead center to the top dead center against the elastic force (biasing force) of the coil spring 36 by engaging the gear engagement portion 32A1 with a gear 22 described later. The top dead center of the plunger 32 is set in an area on the upper end side of the tool body 12, and the bottom dead center is set in an area between the top dead center and the nose portion 12D. Therefore, when the plunger 32 moves from the top dead center to the bottom dead center, the plunger 32 moves in a striking direction DR1 approaching the injection port 12A, and when the plunger 32 moves from the bottom dead center to the top dead center, the plunger 32 moves in a moving away direction DR2 moving away from the injection port.

[0032] The first side wall 32A of the plunger 32 is further provided with a wire engaging portion 32A2. The wire engaging portion 32A2 is formed in a hook shape. The wire engaging portion 32A2 includes a first portion 32A21 formed by protruding inward from the inner wall surface of the first side wall 32A (i.e., in a direction approaching the third side wall 32C), and a second portion 32A22 extending from an end of the first portion 32A21 in a direction approaching the top dead center.

[0033] The surface of the first portion 32A21 facing the top dead center becomes a pressure receiving surface for applying a force from the wire 40 to the plunger 32 in the thrust direction DR1. The second portion 32A22 restricts the wire 40 from shifting in a direction approaching the third side wall portion 32C. Furthermore, by forming the first portion 32A21 to protrude in a direction approaching the third side wall portion 32C, it is possible to extend the wire 40 engaging with the pressure receiving surface of the first portion 32A21 along the inner wall surface of the first side wall portion 32A. Therefore, it is also possible to suppress the wire 40 from shifting in a direction away from the third side wall portion 32C. In addition, the wire engaging portion 32A2 is formed symmetrically with respect to a virtual plane IP1 (FIG. 6) that is parallel to a plane that approximates the second side wall portion 32B and the fourth side wall portion 32D and is equidistant from both planes. With this configuration, it is possible to prevent the plunger 32 from tilting due to an imbalance of the force acting on the plunger 32 from the wire 40 being lost.

[0034] 6 and 7, the second side wall portion 32B and the fourth side wall portion 32D are formed symmetrically with respect to the imaginary plane IP1. The second side wall portion 32B and the fourth side wall portion 32D are provided with guide rollers 32B1 and 32D1 for engaging with the guide rail 46, respectively. The guide rollers 32B1 and 32D1 are provided in pairs on the top dead center side and the bottom dead center side, and therefore, by engaging each of the two guide rollers 32B1 and 32D1 with the guide rail 46, it is possible to suppress the plunger 32 from tilting during movement.

[0035] The third side wall portion 32C is provided with a driver engagement portion 32C1 that is formed symmetrically with respect to the imaginary plane IP1 and to which the rear end of the driver 34 is coupled. This makes it possible to prevent the plunger 32 from tilting due to the reaction force that the plunger 32 receives when the driver 34 strikes the fastener F.

[0036] As shown in these drawings, when the direction of movement of plunger 32 (the direction connecting top dead center and bottom dead center) is used as a reference, plunger 32 is configured so that the distance between driver engagement portion 32C1 and injection port 12A is smaller than the distance between wire engagement portion 32A2 and injection port 12A (wire engagement portion 32A2 is located farther away from injection port 12A in the direction DR2 away from driver engagement portion 32C1).

[0037] 3, the cylinder 44 is a member that houses the coil spring 36 and guides the moving direction of the pin 38A that is a part of the moving member 38. The cylinder 44 according to this embodiment includes a cylindrical portion 44A formed in a cylindrical shape and a cap portion 44C that corresponds to a lid for the cylindrical portion 44A. The cylinder 44 penetrates a hollow area surrounded by four side wall portions of the plunger 32, and is fixed to the housing 12 (the base portion 30A of the plunger assembly 30) so that the moving direction of the plunger 32 and the central axis C of the cylinder 44 are approximately parallel to each other.

[0038] As shown in Figs. 4 and 5, a coil spring 36 made of a compression spring that can expand and contract in the direction A (also called the central axis direction or the expansion direction) of the central axis C of the cylinder 44, i.e., in the moving direction of the plunger 32, is accommodated inside the cylinder 44. This allows the cylinder 44 to serve as a guide member for the coil spring 36 to expand and contract straight along the axis. One end 36A of the coil spring 36 is placed on the bottom surface of the cylinder on the injection port side (bottom dead center side of the plunger 32). A rubber washer may be provided between the coil spring 36 and the bottom surface of the cylinder. A moving member 38 is disposed on the other end 36B of the coil spring 36, and tension is applied to the one end 36A side (lower side) of the moving member 38 by a wire 40. Therefore, the other end 36B of the coil spring 36 and the moving member 38 are configured to be movable together, and when the coil spring 36 compresses from an extended state, the other end 36B of the coil spring 36 and the moving member 38 move in a shooting direction DR1, and when the coil spring 36 expands from a compressed state to an original state, the other end 36B of the coil spring 36 and the moving member 38 move in a moving direction DR2 away from the injection port 12A. As shown in Figure 3, a pair of holes 44B extending parallel to the central axis C, i.e., parallel to the expansion / contraction direction A of the coil spring 36, are formed in the wall of the cylinder 44.

[0039] As shown in Figs. 4 and 5, the moving member 38 directly or indirectly engages with a portion of the wire 40, thereby moving the wire 40 together with the expansion and contraction of the coil spring 36 (movement of the other end 36B). The moving member 38 according to this embodiment includes a cylindrical portion 38B disposed at the other end 36B of the coil spring, and a pin 38A fixed to the cylindrical portion 38B and engaged with both ends of the wire 40. In this embodiment, a pair of holes 44B formed in the wall of the cylinder 44 shown in Fig. 3 are formed at a position that is parallel to two planes that approximate the first side wall portion 32A and the third side wall portion 32C of the plunger 32 shown in Fig. 6 and intersects with an imaginary plane IP2 that passes through the central axis C of the cylinder 44 and the coil spring 36. In addition, both ends of the pin 38A engage with the pair of holes 44B so that the extending direction of the pin 38A is approximately parallel to the imaginary plane IP2. For this reason, even if the moving member 38 including the pin 38A moves in the central axis direction A of the cylinder 44 as the coil spring 36 expands or compresses, it is possible to prevent the pin 38A and the wire 40 from twisting in the circumferential direction of the cylinder 44. This point will be described in detail in the "rotation suppression portion" described later.

[0040] As shown in FIG. 4 and FIG. 5, the wire 40 is a member that is attached to the moving member 38 and the plunger 32 to link the moving member 38 and the plunger 32. In this embodiment, the wire 40 has one end formed in a ring shape, and the pin 38A is inserted into the ring-shaped portion to engage with the pin 38A. The wire 40 that engages with the pin 38A passes through an axial hole in the cylindrical portion 38B of the moving member 38 and extends in the thrust direction DR1 along the central axis C of the coil spring 36, passes through a hole formed in the bottom surface of the cylinder 44, and then is wound around the pulley 42 to change direction, extends in the separation direction DR2, and engages with the pressure-receiving surface of the wire engagement portion 32A2 of the plunger 32. The wire 40 then extends in the thrust direction DR1, is wound around the pulley 42 to change direction, and extends in the separation direction DR2 along the central axis of the coil spring 36. The other end of the wire 40 is formed into a loop, and the wire 40 engages with the pin 38A by inserting the pin 38A through the loop-shaped portion. Thus, both ends of the wire 40 engage with the pin 38A, and the middle portion of the wire 40 engages with the plunger 32.

[0041] That is, the wire 40 includes a first portion 40A including one end portion that engages with the moving member 38, a second portion 40B including a portion connected to the first portion 40A and extending in the projecting direction DR1, a third portion 40C including a portion connected to the second portion 40B and extending approximately in the receding direction DR2, a fourth portion 40D connected to the third portion 40C and engaging with the plunger 32, a fifth portion 40E connected to the fourth portion 40D and including a portion extending approximately in the projecting direction DR1, a sixth portion 40F connected to the fifth portion 40E and including a portion extending in the receding direction DR2, and a seventh portion 40G connected to the sixth portion 40F and including the other end portion that engages with the moving member 38. As shown in FIG. 7, the first portion 40A and the seventh portion 40G of the wire 40 each constitute an end portion of the wire 20 and are formed in a ring shape. The first part 40A and the seventh part 40G are formed into a ring shape by folding back the ends of the wires and tightening the wires with sleeves 40A1 and 40G1, respectively. In addition, the first part 40A and the seventh part 40G have different sizes of link shapes, so that the positions of the sleeve 40A1 of the first part 40A and the sleeve 40G1 of the seventh part 40G are shifted in the vertical direction. This allows the sleeves 40A1 and 40B1 to be positioned inside the coil spring 36 while maintaining the inner diameter of the coil spring 36 small.

[0042] As shown in FIG. 2, the drive mechanism for moving the plunger 32 from the bottom dead center to the top dead center is composed of a motor 20 and a gear 22. The motor 20 according to this embodiment is composed of a three-phase DC brushless motor, and is arranged, for example, on the front side of the bridge portion 12C in the housing 12 so that the output shaft of the motor 20 is approximately perpendicular to the driving direction DR1 and the moving away direction DR2. A gear having the output shaft of the motor 20 as a rotation axis meshes with a first gear 22A constituting the gear 22, and the first gear 22A meshes with a second gear 22B constituting the gear 22. The first gear 22A is arranged in the moving away direction DR2 with respect to the gear of the output shaft of the motor 20, and the second gear 22B is arranged in the moving away direction DR2 with respect to the first gear 22A. The first gear 22A and the second gear 22B are provided with torque rollers (not shown) that are parallel to the rotation axis and protrude in a direction approaching the outer wall surface of the first side wall portion 32A of the plunger 32. The torque roller rotates around the central axis of the first gear 22A (second gear 22B) as the first gear 22A (second gear 22B) rotates. Since the central axis of the first gear 22A (second gear 22B) is parallel to the output shaft of the motor 20, the torque roller reciprocates in the thrust direction DR1 and the separation direction DR2 as the first gear 22A (second gear 22B) rotates. When the plunger 32 is near the bottom dead center, the torque roller of the first gear 22A engages with one of the convex portions provided on the bottom dead center side as the gear engagement portion 32A1. Then, the torque roller moves in the separation direction DR2 as the first gear 22A rotates, and pushes up the gear engagement portion 32A1 of the plunger 32 in the separation direction DR2, so that the plunger 32 can be moved in the separation direction DR2. When the torque roller of the first gear 22A moves to the farthest position in the separating direction DR2, the torque roller of the second gear 22B engages with the other convex portion provided on the top dead center side as the gear engagement portion 32A1. As the second gear 22B rotates, the torque roller moves in the separating direction DR2, pushing the gear engagement portion 32A1 of the plunger 32 further in the separating direction DR2, so that the plunger 32 can be moved further in the separating direction DR2. When the torque roller of the second gear 22B moves to the farthest position in the separating direction DR2, the plunger 32 reaches the top dead center, and the engagement between the gear engagement portion 32A1 and the second gear 22B is released.

[0043] Various techniques can be used to move the plunger using a gear or the like driven by a motor, and at the top dead center, disengage the gear or the like from the plunger to move the plunger toward the bottom dead center.

[0044] The driving tool 10 further includes a control unit (not shown) for driving the motor 20. The control unit is mounted on a PCB board 24 (FIG. 2) disposed in the bridge portion 12C between the motor 20 and the battery B. The control unit includes a non-volatile semiconductor memory (e.g., a flash memory) for storing a computer program for executing the arithmetic processing described in the present embodiment, such as a control program for the motor 20, a volatile semiconductor memory (SRAM and DRAM) for temporarily storing data such as the results of the arithmetic processing, a microcontroller for executing the computer program read from the semiconductor memory and generating a control command (a PWM signal supplied to the base (or gate) of the inverter circuit), and a driver circuit for generating a drive signal based on the control command. The driver circuit is composed of a three-phase bridge-connected inverter circuit provided between DC busbars connected to the positive and negative terminals, which are the output terminals of the battery B. The output terminal of the driver circuit is connected to the three-phase windings constituting the stator of the motor 20.

[0045] [How to insert] A driving method using the driving tool 10 described above will be described below.

[0046] In the initial state, the plunger 32 is in a standby position between the top dead center and the bottom dead center. In this state, when the operator holds the grip portion 12B, presses the contact arm 12D1 against the driving target, and presses the trigger 12E, the battery B and the motor 20 are electrically connected, and the rotor of the motor 20 starts to rotate.

[0047] When the rotor of the motor 20 starts to rotate, the first gear 22A meshing with the gear directly connected to the output shaft of the motor 20 and the second gear 22B meshing with the first gear 22A start to rotate. The torque roller provided on the second gear 22B comes into contact with the gear engagement portion 32A1 of the plunger 32 and pushes the plunger 32 up in the separation direction DR2. Since the plunger 32 is connected to the moving member 38 by the wire 40, the moving member 38 moves in the ejection direction DR1 while compressing the coil spring 36 in conjunction with the movement of the plunger 32 in the separation direction DR2. The closer the plunger 32 approaches the top dead center, the more the coil spring 36 is compressed, and the biasing force of the coil spring 36 becomes larger.

[0048] When the plunger 32 reaches the top dead center, the engagement between the plunger 32 and the gear 22 (torque roller) is released. As a result, the coil spring 36, which is in a compressed state, expands all at once. The moving member 38 moves together with the other end 36B of the coil spring 36 in the separation direction DR2, which is the direction in which the coil spring 36 expands. Since the moving member 38 is connected to the plunger 32 by the wire 40, the plunger 32 and the driver 34 move in the ejection direction DR1 in conjunction with the movement of the moving member 38 in the separation direction DR2. When the plunger 32 descends toward the bottom dead center, the driver 34, which moves together with the plunger 32 in the ejection direction DR1, ejects the fastener F supplied to the nose portion 12D in the ejection direction DR1. The fastener F is ejected from the injection port 12A.

[0049] Next, the rotor of the motor 20 continues to rotate, moving the plunger 32, which is near the bottom dead center, to the standby position. The torque roller provided on the first gear 22A contacts the gear engagement portion 32A1 of the plunger 32 and pushes the plunger 32 up in the separation direction DR2. When the plunger 32 reaches the standby position, the rotor of the motor 20 stops rotating. Thus, the driving of the fastener F is completed. Thereafter, when continuing to drive the fastener F, the trigger 12E is released once and then pressed down again, causing the rotor of the motor 20 to rotate again and the above-mentioned operation to be performed, driving the fastener F.

[0050] [Rotation suppression section] The driving tool 10 according to the present invention is characterized in that it includes a rotation suppressing portion 100 that suppresses the rotation of the moving member 38 relative to the coil spring 36 around an axis in the expansion / contraction direction A. An example of the rotation suppressing portion 100 will be described below. Fig. 8 is a side view of a portion of the plunger assembly 30, and Fig. 9 is a cross-sectional view of the portion of the plunger assembly 30 as viewed from the side.

[0051] The rotation suppression portion 100 has, for example, as shown in Figures 3, 8 and 9, a hole 44B as a guide portion formed in the cylinder 44 along the expansion / contraction direction A of the coil spring 36, a pin 38A as a slider portion attached to the movable member 38 and inserted into the hole 44B, a low-friction member 110 arranged on the surface of the movable member 38 facing the coil spring 36, and a buffer member 111 arranged between the low-friction member 110 and the coil spring 36.

[0052] As shown in Figures 3 and 8, the hole 44B is formed long along the expansion / contraction direction A of the coil spring 36 (the longitudinal direction of the cylinder 44). The hole 44B is formed so that the width in the circumferential direction R around the central axis C of the coil spring 36 is narrow at the expansion part of the coil spring 36 (the upper part of the cylinder 44 in Figures 3 and 8), gradually widens from there toward the contraction part of the coil spring 36 (the lower part of the cylinder 44 in Figures 3 and 8), and becomes constant from the middle. The holes 44B are provided on both sides of the imaginary plane IP1 (shown in Figure 6) of the cylinder 44 (both sides in the left-right direction Y of the cylinder 44) so ​​as to face each other.

[0053] FIG. 10 is a perspective view showing an example of the moving member 38, the low friction member 110, and the buffer member 111. As shown in FIG. 10, the moving member 38 has a pin 38A and a cylindrical portion 38B. The cylindrical portion 38B is made of, for example, resin. The cylindrical portion 38B has, for example, a first cylindrical portion 120 and a second cylindrical portion 121 that are integrated with each other in the axial direction C. The first cylindrical portion 120 has an outer diameter larger than that of the second cylindrical portion 121, and the first cylindrical portion 120 is disposed on the opposite side of the coil spring 36 (the extension side of the coil spring 36, the upper side in FIG. 10), and the second cylindrical portion 121 is disposed on the coil spring 36 side (the contraction side of the coil spring 36, the lower side in FIG. 10).

[0054] The first cylindrical portion 120 has a pair of opposing notches 130 on an end surface opposite to the coil spring 36. The longitudinal direction of the pin 38A faces the left-right direction Y perpendicular to the axial direction C of the cylindrical portion 38B. The pin 38A is longer than the outer diameter of the cylindrical portion 38B. As shown in FIG. 11, the pin 38A is fitted into the notches 130 of the cylindrical portion 38B and protrudes outward from the outer circumferential surfaces on both sides of the cylindrical portion 38B.

[0055] The pin 38A has a holding portion 140 at the center that hooks and holds the wire 40, and has engagement portions 141 at both ends that are inserted into and engage with the hole 44B. The engagement portion 141 is inserted into the hole 44B as shown in Figures 3, 8, and 5. The engagement portion 141 has an outer diameter that is approximately the width of the uppermost portion of the hole 44B, for example. This allows the pin 38A to barely move in the circumferential direction R at the uppermost portion of the hole 44B, but to move more in the circumferential direction R in other portions of the hole 44B.

[0056] 10, the low-friction member 110 is a flat ring made of a smooth metal, and has a smaller coefficient of friction with respect to the coil spring 36 than at least one of the cylindrical portion 38B of the moving member 38 and the buffer member 111. The low-friction member 110 is attached, for example, to the end surface of the first cylindrical portion 120 of the moving member 38 on the coil spring 36 side.

[0057] The buffer member 111 is a rubber ring, which is an elastic body. The buffer member 111 is attached to the outer periphery of the second cylindrical portion 121 of the moving member 38. A locking portion 121A that protrudes in the outer diameter direction is formed at the tip of the second cylindrical portion 121, and the buffer member 111 can be integrated with the moving member 38 by fitting the buffer member 111 into the second cylindrical portion 121 and locking the buffer member 111 with the locking portion 121A. This prevents the buffer member 111 from coming off the moving member 38.

[0058] For the above reasons, for example, as shown in Fig. 9, inside the cylinder 44, the coil spring 36, the buffer member 111, the low-friction member 110, and the moving member 38 are arranged in this order along the extension direction (upward direction) of the coil spring 36. Then, as shown in Fig. 8, the engaging portion 141 of the pin 38A of the moving member 38 is engaged with the hole 44B of the cylinder 44, and as shown in Fig. 7, the holding portion 140 of the pin 38A holds one end of the wire 40 passing through the central axis C of the coil spring 36.

[0059] 12 is an exploded view showing a portion of the cylinder 44 and the guide rail 46. The cylinder 44 has a cylindrical portion 44A and a cap portion 44C. The cylindrical portion 44A has a cylindrical shape with both ends open, and is provided upright toward the extension direction A of the coil spring 36 relative to the base portion 30A (tool body 12) of the plunger assembly 30. The end (upper end) of the cylindrical portion 44A facing the extension direction of the coil spring 36 is closed by the cap portion 44C.

[0060] The cylindrical portion 44A and the cap portion 44C are fitted together so as not to rotate around the central axis C. The fitting mechanism between the cylindrical portion 44A and the cap portion 44C is not particularly limited, but for example, a concave cutout 150 is formed at the upper end of the cylindrical portion 44A, and a convex protrusion 151 is formed on the inner circumferential surface of the cap portion 44C, and the cylindrical portion 44A is inserted into the inside of the cap portion 44C to fit the cutout 150 and the protrusion 151.

[0061] The cap portion 44C includes a pair of fixing portions 161 having screw holes 160 on both sides in the left-right direction Y perpendicular to the central axis C, for example. Each fixing portion 161 is fixed to each guide rail 46 on both sides of the cylinder 44 by a screw 162. The guide rail 46 is fixed to the base 30A of the plunger assembly 30, and thus the cylinder 44 is fixed to the tool body 12 so as not to rotate around the central axis C.

[0062] Then, as shown in FIG. 4, when the plunger 32 moves in the direction of separation DR2, the wire 40 pulls the moving member 38, and the coil spring 36 contracts together with the moving member 38 in the direction of ejection DR1, the pin 38A of the moving member 38 descends along the hole 44B of the cylinder 44. At this time, the pin 38A of the moving member 38 is guided in the direction of expansion and contraction A by the hole 44B, but since the width of the hole 44B is wide, the rotation of the moving member 38 around the central axis C is permitted to a certain extent, and the contact between the pin 38A and the edge of the hole 44B of the cylinder 44 is reduced or eliminated. As a result, the resistance during the movement of the moving member 38 is reduced. Then, when the plunger 32 is disengaged from the gear 22 and the coil spring 36 expands in the direction of separation DR2 as shown in FIG. 5, the pin 38A of the moving member 38 ascends along the hole 44B of the cylinder 44. At this time, the pin 38A of the moving member 38 is guided in the expansion / contraction direction A by the hole 44B, but since the width of the hole 44B is initially wide, the contact between the pin 38A and the cylinder 44 is reduced or eliminated, and the resistance during the movement of the moving member 38 is reduced. Then, as shown in FIG. 8, when the coil spring 36 is expanded, that is, when the pin 38A reaches the upper part of the hole 44B, the width of the hole 44B becomes narrower, and the rotation of the moving member 38 around the central axis C is not permitted. Then, after reaching the maximum expansion position once, the coil spring 36 repeats small expansion and contraction near the upper end of the cylinder 44 due to its restoring force. At this time, since the speed of expansion and contraction of the coil spring 36 and the moving speed of the moving member 38 are not the same, the contact between the moving member 38 and the other end 36B of the coil spring 36 is not maintained, and the moving member 38 and the other end 36B of the coil spring 36 come into contact with and separate from each other during the repeated expansion and contraction of the coil spring 36. At this time, the moving member 38 tends to shift in the rotational direction relative to the coil spring 36. In particular, since the other end 36B of the coil spring 36 rotates when it expands or contracts, the moving member 38 is likely to rotate relative to the coil spring 36. However, since the moving member 38 is guided in the hole 44B by the pin 38A, rotation around the axis in the expansion / contraction direction A relative to the coil spring 36 is suppressed.

[0063] According to this embodiment, the driving tool 10 is provided with a rotation suppression section 100 that suppresses the rotation of the movable member 38 around the central axis C in the extension / contraction direction A relative to the coil spring 36, thereby suppressing twisting of the wire 40 connected to the movable member 38.

[0064] The rotation suppressing portion 100 has a hole 44B as a guide portion formed along the expansion / contraction direction A of the coil spring 36, and a pin 38A as a slider portion attached to the moving member 38 and moving along the hole 44B. This effectively suppresses the rotation of the moving member 38 relative to the coil spring 36, and suppresses twisting of the wire 40. In addition, the rotation of the moving member 38 can be suppressed with a simple structure that utilizes the hole 44B of the cylinder 44 and the pin 38A of the moving member 38. As a result, the driving tool 10 can be made smaller and lighter.

[0065] The hole 44B of the cylinder 44 is formed such that the width in the circumferential direction R of the upper part is narrower than the width of the other parts, and is configured so that the amount of rotation of the moving member 38 permitted at the position when the coil spring 36 is extended is greater than the amount of rotation of the moving member 38 permitted at other positions. With this configuration, it is possible to sufficiently suppress the rotation of the moving member 38 relative to the coil spring 36 at the position when the coil spring 36 is extended, while allowing the moving member 38 to rotate freely at positions other than the position when the coil spring 36 is extended, and to suppress the hole 44B and the pin 38A from becoming resistance to the extension and contraction movement of the coil spring 36. As a result, the extension and contraction movement of the coil spring 36 and the driving movement of the plunger 32 can be performed appropriately.

[0066] The rotation suppression unit 100 is disposed between the moving member 38 and the coil spring 36, and has a low-friction member 110 having a smaller coefficient of friction with respect to the coil spring 36 than at least the moving member 38. This reduces the force transmitted from the coil spring 36 to the moving member 38 when the coil spring 36 and the moving member 38 come into contact with each other, making it possible to suppress rotation of the moving member 38 relative to the coil spring 36. As a result, twisting of the wire 40 can be suppressed.

[0067] The rotation suppression section 100 has a buffer member 111 interposed between the moving member 38 and the coil spring 36. This reduces the impact when the coil spring 36 and the moving member 38 come into contact with each other, and also reduces the amount of repulsion of the coil spring 36 against the moving member 38, making it difficult for the coil spring 36 to separate from the moving member 38. As a result, rotation of the moving member 38 relative to the coil spring 36 is suppressed, and twisting of the wire 40 can be suppressed.

[0068] The cylinder 44 is fixed to the guide rail 46 of the plunger 32. This prevents the cylinder 44 itself from rotating in the circumferential direction R. As a result, the hole 44B of the cylinder 44 does not rotate, and the rotation of the moving member 38 can be appropriately suppressed by the pin 38A that engages with the hole 44B.

[0069] The cylinder 44 has a cylindrical portion 44A and a cap portion 44C, the cylindrical portion 44A and the cap portion 44C are fitted together, and the cap portion 44C is fixed to the guide rail 46. This effectively prevents the cylinder 44 from rotating, and as a result, the hole 44B of the cylinder 44 effectively suppresses the rotation of the moving member 38 relative to the coil spring 36. In this case, the hole 44B of the cylinder 44 may have a shape that reaches the upper end of the cylinder 44 and opens at the upper end. This improves the ease of assembly of the moving member 38 to the cylinder 44.

[0070] The extension of the coil spring 36 moves the plunger 32 in the driving direction DR1 of the fastener F, and the extension direction of the coil spring 36 and the driving direction DR1 of the fastener F are opposite directions. That is, when the fastener F is driven, the coil spring 36 extends in the moving away direction DR2, and the plunger 32 moves in the driving direction DR1. In this case, the center of gravity of the coil spring 36 moves in the moving away direction DR2 when the fastener is driven, and the movement of the center of gravity of the coil spring 36 can be used to absorb the reaction caused by the movement of the plunger 32 when the fastener is driven. Therefore, the driving tool 10 has a function of absorbing the reaction caused when the driving tool 10 is driven, and there is no need to provide a dedicated member that was necessary in the conventional reaction absorbing mechanism, so that the driving tool 10 can be made lighter and smaller.

[0071] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, the present invention is not limited to such an example. It is clear that a person skilled in the art can come up with various modified or altered examples within the scope of the ideas described in the claims, and it is understood that such examples also naturally belong to the technical scope of the present invention.

[0072] For example, in the above embodiment, the guide portion of the rotation suppression portion 100 is the hole 44B of the cylinder 44, and the slider portion is the pin 38A of the moving member 38, but the guide portion and slider portion of the rotation suppression portion 100 may have other structures using known technology. For example, the guide portion may be a rail provided separately from the cylinder 44, and the slider portion may be a slider that engages with the rail and moves along the rail.

[0073] The rotation suppressing unit 100 may not include the low friction member 110 or the buffer member 111. The rotation suppressing unit 100 may not include a guide unit and a slider unit, and may include at least one of the low friction member 110 and the buffer member 111. The shapes and numbers of the hole 44B of the guide unit, the pin 38A of the slider unit, the low friction member 110, and the buffer member 111 are not limited to those in the above embodiment. Furthermore, the rotation suppressing unit 100 may suppress the rotation of the moving member 38 using a technique other than the guide unit, the slider unit, the low friction member 110, and the buffer member 111.

[0074] The moving member 38 may have a structure other than the pin 38A and the cylindrical portion 38B. The moving member 38 may be made partly or entirely of resin and be light, or partly or entirely of metal and be heavy. The cylinder 44 does not have to have a structure having the cylindrical portion 44A and the cap portion 44C, and the cap portion 44C may not be fixed to the guide rail 46 but may be fixed to another portion. The cylinder 44 may be fixed to another portion of the tool body 12.

[0075] In the plunger assembly 30 described in the above embodiment, the extension direction of the coil spring 36 and the ejection direction DR1 of the fastener F are opposite to each other, but the present invention can be applied even if they are in the same direction or at right angles to each other.

[0076] Other configurations of the driving tool 10 are not limited to those in the above embodiment. For example, the coil spring 36 may be a single spring as in the above embodiment, or may be composed of a plurality of springs arranged in series. In the present embodiment, the coil spring 36 has a rectangular cross-sectional shape in order to reduce the overall height, but a cross-sectional shape of an ellipse or oval may also be used. The biasing member is not limited to a coil spring, and may be another type of spring or elastic body. The string-like member may be something other than a wire.

[0077] Furthermore, the present invention can be applied to a driving tool for driving fasteners other than nails. In addition, various modifications of the present invention are possible within the scope of the ordinary creative ability of those skilled in the art. [Industrial Applicability]

[0078] The present invention is useful in providing a driving tool capable of suppressing twisting of a string-shaped member. [Explanation of symbols]

[0079] 10 Driving tool 12 Housing (tool body) 12A injection port 12B Grip section 12C Bridge 12D Nose 12E Trigger 12F Trigger biasing member 14 Magazine 14A Pusher 20 Motor 22 Gear 22A 1st Gear 22B 2nd Gear 24 PCB board 30 Plunger Assembly 30A base 32 Plunger 32A 1st side wall part 32A1 Gear engagement part 32A2 Wire engagement part 32B 2nd side wall part 32C 3rd side wall part 32C1 Driver engagement part 32D 4th side wall part 34 Drivers 36 Coil spring 36A One end of coil spring 36B Other end of coil spring 38 Moving parts 38A pin 38B Cylindrical section 40 Wire 42 Pulley 44 Cylinder 44A Cylindrical section 44B hole 44C Cap 46 Guide Rail 100 Rotation suppression section 110 Low friction materials 111 Cushioning material 120 First cylindrical part 121 Second cylindrical part 130 Cutout 140 Holding part 141 Engagement part 150 Cutout 151 Protrusion 160 screw holes 161 Fixed part 162 Screw A Stretching direction (center axis direction) X Anteroposterior direction Y left / right direction Z vertical direction C center axis R Circumferential direction around the central axis B Battery DR1 Launch direction DR2 Leaving direction F Fastener

Claims

1. A plunger movable in a direction in which the fastener is driven out; A biasing member that is extendable and contracts and serves as a drive source for the plunger; a movable member disposed at an end of the biasing member in a stretching direction and movable in the stretching direction of the biasing member; a string-like member that connects the moving member and the plunger and transmits the driving force of the biasing member to the plunger via the moving member; a rotation suppression portion that suppresses the rotation of the moving member around a central axis in the extension / contraction direction of the biasing member, The rotation suppressing portion is A guide portion formed along the extension / contraction direction of the biasing member; a slider portion provided on the moving member and moving along the guide portion, A driving tool, wherein the guide portion is configured so that the amount by which the movable member is permitted to rotate is greater in other positions than the amount by which the movable member is permitted to rotate when the biasing member is extended.

2. A plunger movable in a direction in which the fastener is driven out; A biasing member that is extendable and contracts and serves as a drive source for the plunger; a movable member disposed at an end of the biasing member in a stretching direction and movable in the stretching direction of the biasing member; a string-like member that connects the moving member and the plunger and transmits the driving force of the biasing member to the plunger via the moving member; a rotation suppression portion that suppresses the rotation of the moving member around a central axis in the extension / contraction direction of the biasing member, The rotation suppressing portion is A driving tool comprising: a low-friction member disposed between the moving member and the urging member, the low-friction member having a smaller coefficient of friction with respect to the urging member than at least the moving member.

3. The rotation suppressing portion is A guide portion formed along the extension / contraction direction of the biasing member; The driving tool according to claim 2 , further comprising: a slider portion provided on the moving member and configured to move along the guide portion.

4. A cylinder that accommodates the biasing member is further provided. the guide portion is a hole formed in the cylinder, The driving tool according to claim 1 or 3, wherein the slider portion is a pin and is inserted into the hole.

5. A guide rail for guiding the plunger in a direction in which the fastener is driven out is further provided. The driving tool according to claim 4 , wherein the cylinder is fixed relative to the guide rail.

6. The cylinder has a cylindrical portion and a cap portion, The cylindrical portion and the cap portion are fitted together, The driving tool according to claim 5 , wherein the cap portion is fixed to the guide rail.

7. The rotation suppressing portion is The driving tool according to any one of claims 1 to 6, further comprising a buffer member interposed between the moving member and the biasing member.

8. The plunger moves in a direction to drive the fastener by the extension action of the biasing member, The driving tool according to any one of claims 1 to 7, wherein an extension direction of the urging member and a driving direction of the fastener are opposite directions.

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