JP7707579B2 - Fastening tool - Google Patents

Description

The present invention relates to a fastening tool in which a driver bit is engaged with a screw, the driver bit is used to push the screw against an object to be fastened, and the driver bit is rotated to screw the screw in.

There is a known tool known as a portable fastener driver that uses the air pressure of compressed air supplied by an air compressor or the combustion pressure of gas to drive connecting fasteners loaded in a magazine one by one from the tip of a driver guide.

As a screw driver that utilizes the combustion pressure of gas, there is a screw driver that is equipped with a small gas cylinder in the main body and can be used cordlessly, and a screw driver that uses screws as the connecting fastener to be driven has been proposed (see, for example, Patent Document 1).

A screw driver has also been proposed in which a spring is compressed by the driving force of a motor that rotates the screw, and the screw is driven in by the force of the spring (see, for example, Patent Document 2).

Patent No. 5590505 Patent No. 6197547

In screw drivers that utilize the combustion pressure of the gas described above, a configuration is adopted in which the screw is biased by a biasing member and sent to the nose section. Also, screw drivers that drive screws using the bias of a spring also adopt a configuration in which the screws are sent by combining the electromagnetic force of a solenoid or other such device with a biasing means. However, in a configuration in which multiple screws are connected by a connector and supplied in a rolled form, the biasing force of the biasing member or the output of the solenoid is insufficient to send the screws, or the stroke for sending the screws cannot be secured, making it difficult to send the screws by the specified feed amount. Also, in order to be able to send the screws in the above form using a solenoid, a large solenoid is required, which increases the size of the tool.

The present invention has been developed to solve these problems, and aims to provide a fastening tool that uses the driving force of a motor to feed the screw.

In order to solve the above-mentioned problems, the present invention provides a fastening tool comprising a screw storage section in which screws are stored, and a screw feed section which feeds the screws stored in the screw storage section to an injection passage through which a driver bit passes, the screw feed section comprising a screw feed motor, an engagement section which engages with the screw, and a screw feed transmission section which transmits the driving force of the screw feed motor to the engagement section, the screw feed section being a unit integrally assembled from the screw feed motor, the engagement section, and the screw feed transmission section which is attached to the tool body , and the portion of the screw feed transmission section which is connected to the engagement section is supported so as to be able to move back and forth along the direction in which the screw is fed .

In the present invention, the screw feed unit feeds the screw by engaging the engagement part, which is driven by a screw feed motor.

In the present invention, the screw feed section uses a screw feed motor as a drive source, so that even in a configuration in which multiple screws are connected by a connector and supplied in a rolled form, a motor of a size that can be mounted on a tool used by hand can provide sufficient force to feed the screws and feed the screws at a specified feed rate. This also prevents the tool from becoming larger. Furthermore, by controlling the amount of rotation of the screw feed motor, it is possible to control and adjust the screw feed rate, which is easier to control and adjust than in a configuration in which screws are fed by spring force or a solenoid.

1 is a side cross-sectional view showing an example of an internal structure of a fastening tool according to an embodiment of the present invention. FIG. 2 is a partially cutaway perspective view showing an example of the internal structure of the fastening tool of the present embodiment. FIG. 2 is a partially cutaway perspective view showing an example of the internal structure of the fastening tool of the present embodiment. FIG. 2 is a partially cutaway perspective view showing an example of the internal structure of the fastening tool of the present embodiment. FIG. 2 is a side view showing an example of the fastening tool of the present embodiment. FIG. 2 is a front view showing an example of the fastening tool of the present embodiment. FIG. 2 is a top view showing an example of the fastening tool of the present embodiment. FIG. 1 is a perspective view showing an example of a fastening tool according to an embodiment of the present invention. FIG. 1 is a perspective view showing an example of a fastening tool according to an embodiment of the present invention. FIG. 2 is a perspective view showing details of a screw feed unit according to the present embodiment. FIG. 2 is a perspective view showing an example of a nose portion of the present embodiment. FIG. 2 is a perspective view showing an example of a nose portion of the present embodiment. 5A to 5C are side cross-sectional views showing an example of the operation of the fastening tool of the present embodiment. FIG. 4 is a partially cutaway perspective view showing an example of an operation of the fastening tool according to the present embodiment. FIG. 4 is a partially cutaway perspective view showing an example of an operation of the fastening tool according to the present embodiment. 10 is a perspective view showing an example of an attachment/detachment operation of a driver bit in the fastening tool of the present embodiment. FIG. 10 is a perspective view showing an example of an attachment/detachment operation of a driver bit in the fastening tool of the present embodiment. FIG. FIG. 11 is a side cross-sectional view showing a modified example of the fastening tool of the present embodiment. FIG. 11 is a side cross-sectional view showing another modified example of the fastening tool of the present embodiment. FIG. 13 is a block diagram showing a modified example of the fastening tool of the present embodiment. FIG. 4 is a cross-sectional view showing a fastened state of the screw. FIG. 4 is a cross-sectional view showing a fastened state of the screw. FIG. 4 is a cross-sectional view showing a fastened state of the screw. FIG. 4 is a plan view illustrating an example of a setting unit. 10 is a flowchart showing an example of the operation of a fastening tool according to a modified example of the present embodiment. 13 is a perspective view showing a modified example of the installation position of the setting unit. FIG. 13 is a perspective view showing a modified example of the installation position of the setting unit. FIG. 13 is a perspective view showing a modified example of the installation position of the setting unit. FIG. 13 is a perspective view showing a modified example of the installation position of the setting unit. FIG.

The following describes an embodiment of the fastening tool of the present invention with reference to the drawings.

<Configuration example of fastening tool according to this embodiment>
Fig. 1 is a side cross-sectional view showing an example of the internal structure of a fastening tool of this embodiment, and Figs. 2A to 2C are partially cutaway perspective views showing an example of the internal structure of the fastening tool of this embodiment. Fig. 3A is a side view showing an example of the fastening tool of this embodiment, Fig. 3B is a front view showing an example of the fastening tool of this embodiment, and Fig. 3C is a top view showing an example of the fastening tool of this embodiment. The cut surface in Fig. 1 is line A-A in Fig. 3B. Furthermore, Figs. 4A to 4B are perspective views showing an example of the fastening tool of this embodiment.

The fastening tool 1 of this embodiment includes a tool body 10 and a handle 11. In the fastening tool 1, the handle 11 extends in a direction that intersects with the extension direction of the tool body 10, which extends in one direction. In the fastening tool 1, the direction in which the tool body 10 extends is the front-rear direction, and the direction in which the handle 11 extends is the up-down direction. In addition, the fastening tool 1 includes a battery attachment portion 13 at the bottom of the handle 11, to which a battery 12 is detachably attached.

The fastening tool 1 includes a bit holding part 3 that holds the driver bit 2 rotatably and movably in the forward and backward directions along the axial direction, a first drive part 4 that rotates the driver bit 2 held by the bit holding part 3, and a second drive part 5 that moves the driver bit 2 held by the bit holding part 3 in the forward and backward directions along the axial direction.

The fastening tool 1 also includes a screw storage section 6 in which the screw 200 is stored, a screw feed section 7 which feeds the screw stored in the screw storage section 6, and a nose section 8 which is pressed against an object to be fastened to and from which the screw is ejected.

The bit holding portion 3 includes a holding member 30 that removably holds the driver bit 2, a rotating guide member 31 that supports the holding member 30 so that it can move in the forward and backward directions along the axial direction of the driver bit 2 and rotates together with the holding member 30, a moving member 32 that moves the holding member 30 in the forward and backward directions along the rotating guide member 31, and a biasing member 33 that biases the moving member 32 in the rearward direction.

The holding member 30 is composed of, for example, a cylindrical member whose outer diameter is slightly smaller than the inner diameter of the rotary guide member 31 and which is inserted inside the rotary guide member 31. The holding member 30 has an opening 30a at its front end along the axial direction, the opening 30a having a shape that matches the cross-sectional shape of the insertion portion 20 of the driver bit 2. The holding member 30 has a mechanism in the opening 30a that detachably holds the insertion portion 20 of the driver bit 2 using a known mechanism. The opening 30a of the holding member 30 is exposed to the inside of the rotary guide member 31, and the insertion portion 20 of the driver bit 2 is detachably inserted into the opening 30a.

The rotating guide member 31 extends along the extension direction of the tool body 10 and has a cylindrical shape with the holding member 30 inside. The front end is rotatably supported via a bearing 34a on a metal front frame 10b provided on the front side of a resin case 10a that constitutes the exterior of the tool body 10. The rear end of the rotating guide member 31 is connected to the first drive unit 4.

The rotating guide member 31 has grooves 31a extending in the front-rear direction along the axial direction of the driver bit 2, formed in two radially opposing sides. The rotating guide member 31 penetrates the holding member 30 in the radial direction, and the connecting members 30b protruding from both sides of the holding member 30 enter the grooves 31a, so that the rotating guide member 31 is connected to the holding member 30 via the connecting members 30b.

As a result, when the rotary guide member 31 rotates, the connecting member 30b is pressed into the groove portion 31a of the rotary guide member 31, and the holding member 30 rotates together with the rotary guide member 31. Also, the connecting member 30b of the holding member 30 is guided by the groove portion 31a of the rotary guide member 31, and moves in the front-rear direction along the axial direction of the driver bit 2.

The moving member 32 is an example of a transmission member, and includes a first moving member 32a that rotates together with the holding member 30 and moves the holding member 30 in the forward and backward directions along the rotation guide member 31, a second moving member 32c that is supported by the first moving member 32a via a bearing 32b and pushes the first moving member 32a with the bearing 32b, and a buffer member 32d that is attached to the rear side of the second moving member 32c.

The first moving member 32a is, for example, a cylindrical member whose inner diameter is slightly larger than the outer diameter of the rotating guide member 31 and is inserted outside the rotating guide member 31. The first moving member 32a is connected to the holding member 30 via a connecting member 30b protruding from the groove portion 31a of the rotating guide member 31.

The bearing 32b is inserted between the outer periphery of the first moving member 32a and the inner periphery of the second moving member 32c, and supports the first moving member 32a rotatably relative to the second moving member 32c.

The second moving member 32c is connected to the first moving member 32a via a bearing 32b in a state in which movement in the forward and backward directions along the axial direction is restricted.

As a result, the first moving member 32a is pushed by the second moving member 32c via the bearing 32b as the second moving member 32c moves forward and backward along the axial direction, and moves forward and backward along the axial direction together with the second moving member 32c. In addition, the first moving member 32a is rotatable relative to the second moving member 32c.

The biasing member 33 is composed of a coil spring in this example, and is placed outside the rotation guide member 31 between the front frame 10b provided on the front side of the case 10a of the tool body 10 and the second moving member 32c of the moving member 32, and abuts against a spring seat arranged so as to contact the end face of the outer ring of the bearing 32b. The biasing member 33 is compressed when the moving member 32 moves forward, and applies a force to the moving member 32 that pushes the moving member 32 backward.

The first drive unit 4 includes a bit rotation motor 40 driven by electricity supplied from the battery 12, and a reduction gear 41. The bit rotation motor 40 is an example of a first motor, and the shaft 40a of the bit rotation motor 40 is connected to the reduction gear 41, and the shaft 41a of the reduction gear 41 is connected to the rotation guide member 31. In the first drive unit 4, the reduction gear 41 is configured using a planetary gear, and the bit rotation motor 40 is arranged coaxially with the rotation guide member 31 and the driver bit 2 held by the holding member 30.

The first drive unit 4 has a bit rotation motor 40 and a reducer 41 attached to a metal rear frame 10c provided on the rear side of the case 10a of the tool body 10, and the shaft 41a of the reducer 41 is supported by the rear frame 10c via a bearing 42.

The bit holding unit 3 and the first drive unit 4 are assembled into a unit by connecting the front frame 10b and the rear frame 10c with a connecting member 10d extending in the front-rear direction, and are fixed to the case 10a of the tool body 10 with screws 10e. The bit holding unit 3 and the first drive unit 4 are configured so that they can be attached and detached to the tool body 10 when each part is assembled, which improves assembly ease, as opposed to a configuration in which each part is fixed to the tool body 10 independently.

The front end of the rotary guide member 31 of the bit holding unit 3 is supported by a front frame 10b provided on the front side of the case 10a of the tool body 10 via a bearing 34a, and the rear end of the rotary guide member 31 is supported by a rear frame 10c provided on the rear side of the case 10a via the shaft 41a of the reducer 41 and a bearing 42. Thus, the rotary guide member 31 of the bit holding unit 3 is rotatably supported by the tool body 10.

As a result, the first drive unit 4 rotates the rotary guide member 31 using the bit rotation motor 40. When the rotary guide member 31 rotates, the holding member 30 that holds the driver bit 2 rotates together with the rotary guide member 31 as the connecting member 30b is pressed against the groove portion 31a of the rotary guide member 31.

The second drive unit 5 includes a bit moving motor 50 driven by electricity supplied from the battery 12, and a reduction gear 51. The bit moving motor 50 is an example of a motor, a second motor, and the shaft 50a of the bit moving motor 50 is connected to the reduction gear 51, and the shaft 51a of the reduction gear 51 is connected to a pulley 52, which is an example of a transmission member. In the second drive unit 5, the pulley 52 is supported by the tool body 10 via a bearing 53. In the second drive unit 5, the shaft 50a of the bit moving motor 50 is arranged along the extension direction of the handle 11.

The second drive unit 5 has a wire 54, which is an example of a transmission member, wound around a pulley 52, and the wire 54 is connected to the second moving member 32c of the moving member 32.

As a result, the second drive unit 5 rotates the pulley 52 by the bit moving motor 50 and winds up the wire 54, thereby moving the second moving member 32c forward. As the second moving member 32c moves forward, the first moving member 32a is pushed via the bearing 32b, and the first moving member 32a moves forward together with the second moving member 32c along the axial direction. As the first moving member 32a moves forward, the holding member 30 connected to the first moving member 32a via the connecting member 30b moves forward.

The second drive unit 5 is positioned offset to one side from approximately the center in the left-right direction of the fastening tool 1 so that the tangent direction of the portion of the pulley 52 around which the wire 54 is wound is aligned with the extension direction of the rotary guide member 31. This causes the wire W between the pulley 52 and the second moving member 32c to extend in a straight line along the movement direction of the moving member 32, suppressing an increase in load when the wire 54 is wound around the pulley 52 and an increase in load when the wire W is pulled out from the pulley 52.

The first drive unit 4 is provided on one side of the tool body 10, at the rear, across the handle 11. The second drive unit 5 is provided on the other side of the tool body 10, at the front, across the handle 11.

The screw storage section 6 stores multiple screws 200 connected by a connecting band, forming a spirally wound connected screw.

5 is a perspective view showing the details of the screw feed unit of this embodiment. The screw feed unit 7 includes a screw feed motor 70, a pinion gear 71 attached to the shaft of the screw feed motor 70, a rack gear 72 meshing with the pinion gear 71, and an engagement portion 73 connected to the rack gear 72 and engaging with a connecting screw fed from the screw storage portion 6. The screw feed unit 7 includes the pinion gear 71 and the rack gear 72 and constitutes a screw feed transmission portion that transmits the driving force of the screw feed motor 70 to the engagement portion 73. The engagement portion 73 is biased upward by a compression spring (not shown) via a part in which the rack gear 72 is formed, and is configured so that the engagement portion 73 and the screw 200 do not descend due to their weight when power is not supplied to the screw feed motor 70.

The screw feed unit 7 has a screw feed motor 70 fixed to a subframe 74, and a rack gear 72 supported by the subframe 74 so that it can move up and down along the feed direction of the connecting screw. The screw feed unit 7 is unitized by assembling each part together by fitting the uneven shapes of the claws, etc., and fastening the screws 75, etc.

6A and 6B are perspective views showing an example of a nose portion of this embodiment. The nose portion 8 is an example of a first nose portion, and includes an injection passage configuration portion 80a that configures an injection passage 80 through which the driver bit 2 passes and through which the screw 200 is supplied by the screw feed portion 7, an injection port 81a that communicates with the injection passage 80 and contacts the object to be fastened, a contact arm 82 that moves in the front-rear direction in conjunction with the contact member 81, and an adjustment portion 83 that regulates the amount of movement of the contact arm 82. The nose portion 8 also includes a cover member 88 that can be opened and closed to cover the path through which the screw 200 passes from the screw storage portion 6 to the injection passage 80.

As shown in FIG. 2C, the fastening tool 1 includes a contact switch portion 84 that is activated when pressed by a contact arm 82. As shown in FIG. 1A, the fastening tool 1 includes a nose body portion 10f on the tool body 10, and the nose body portion 10f includes an injection passage component 80b that configures the injection passage 80 in combination with the injection passage component 80a of the nose portion 8. The nose body portion 10f is an example of a second nose portion, and is configured integrally with the front frame 10b, for example. Note that the nose body portion 10f may be configured such that a component independent of the front frame 10b is fixed to the front frame 10b.

The nose portion 8 supports the contact member 81 so that it can move in the front-rear direction, and the contact arm 82 moves in the front-rear direction in conjunction with the contact member 81. The contact member 81 of the nose portion 8 is biased forward by a biasing member (not shown), and the contact member 81, which is pressed against the object to be fastened and moves rearward, is biased by the biasing member to move forward.

In the nose portion 8, the contact member 81 is pressed against the object to be fastened, causing the contact arm 82 to move backward, and the amount of movement of the contact arm 82 until the contact switch portion 84 is activated is adjusted by the adjustment portion 83. The contact switch portion 84 is switched between activated and inactivated when pressed by the contact arm 82, and in this example, the state in which the contact switch portion 84 is not pressed by the contact arm 82 and is inactivated is referred to as the off state of the contact switch portion 84, and the state in which the contact switch portion 84 is pressed by the contact arm 82 and is activated is referred to as the on state of the contact switch portion 84.

The nose portion 8 is unitized by assembling each of the parts constituting the injection passage 80, contact member 81, and contact arm 82 to a subframe 86 by fitting concave and convex shapes such as claws and fastening screws 85, and the unit is fixed to the front frame 10b that constitutes the tool body 10 by screws 87. When the nose portion 8 is fixed to the front frame 10b, the injection passage 80 is formed by the injection passage constituent part 80b of the nose main body part 10f fixed to the tool body 10 side and the injection passage constituent part 80a, which is a part on the nose portion 8 side.

The subframe 86, which has the function of fixing the nose portion 8 to the tool body 10, is formed with an injection passage component 80a that constitutes part of the injection passage 80, and also has the function of positioning the injection passage 80 with respect to the tool body 10. As a result, when the nose portion 8 is fixed to the front frame 10b, the injection passage component 80a is correctly aligned, and even if the nose portion 8 is configured to be detachable from the tool body 10, the injection passage 80 is prevented from shifting in position, particularly in the radial direction, relative to the movement path of the driver bit 2. In addition, the contact switch portion 84 is attached to the tool body 10 side, and when the nose portion 8 is fixed to the front frame 10b, the position of the side of the contact arm 82 facing the contact switch portion 84 is aligned with the contact switch portion 84.

The screw feed portion 7 is configured integrally with the front frame 10b or is fixed to the front frame 10b , and a sub-frame 74 is fixed to the nose body portion 10f that constitutes the tool body 10 by screws 76.

The fastening tool 1 is equipped with a trigger 9 that receives an operation, and a trigger switch unit 90 that is actuated by the operation of the trigger 9. The trigger 9 is provided on the front side of the handle 11 and is configured to be operable by the finger of the hand holding the handle 11. The trigger switch unit 90 is actuated when pressed by the trigger 9.

The trigger switch unit 90 is switched between being activated and not activated when pressed by the trigger 9. In this example, the trigger switch unit 90 is OFF when the trigger 9 is not operated and the trigger switch unit 90 is not pressed by the trigger 9, resulting in an inactivated state, and the trigger switch unit 90 is ON when the trigger 9 is operated and pressed by the trigger 9, resulting in an activated state.

The fastening tool 1 is equipped with a control unit 100 that controls the first drive unit 4, the second drive unit 5, and the screw feed unit 7 based on the output of a trigger switch unit 90 that is activated by operating the trigger 9, and a contact switch unit 84 that is activated by being pressed by a contact member 81. In this example, the control unit 100 is installed inside the battery attachment unit 13 provided at the bottom of the handle 11.

<Operation example of the fastening tool according to the present embodiment>
FIG. 7 is a side cross-sectional view showing an example of the operation of the fastening tool of this embodiment, and FIGS. 8A and 8B are partially cutaway perspective views showing an example of the operation of the fastening tool of this embodiment. Below, the fastening operation of the fastening tool of this embodiment will be described with reference to each of the drawings.

When the fastening tool 1 is in a standby state, as shown in FIG. 1, the tip of the driver bit 2 is located at a standby position P1 behind the injection passage 80, and the screw 200 can be supplied to the injection passage 80.

When the contact member 81 is pressed against the object to be fastened, the contact arm 82 presses the contact switch unit 84 to turn it on, and the trigger 9 is operated to turn the trigger switch unit 90 on, the control unit 100 drives the bit movement motor 50 of the second drive unit 5 and also drives the bit rotation motor 40 of the first drive unit 4 at a predetermined timing.

When the bit moving motor 50 is driven to rotate in one direction, the forward direction, the pulley 52 rotates in the forward direction, causing the wire 54 to be wound around the pulley 52. When the wire 54 is wound around the pulley 52, the second moving member 32c connected to the wire 54 is guided by the rotation guide member 31 and moves forward along the axial direction. When the second moving member 32c moves forward, the first moving member 32a is pushed by the second moving member 32c via the bearing 32b, and moves forward along the axial direction together with the second moving member 32c while compressing the biasing member 33.

When the first moving member 32a moves forward, the holding member 30 connected to the first moving member 32a by the connecting member 30b moves forward along the axial direction of the driver bit 2, with the connecting member 30b being guided by the groove 31a of the rotation guide member 31.

As a result, the driver bit 2 held by the holding member 30 moves forward and engages with the screw 200 supplied to the injection port 81a of the nose portion 8, moving the screw 200 forward and pressing it against the object to be fastened.

When the bit rotation motor 40 is driven to rotate in one direction, the forward direction, the rotation guide member 31 rotates in the forward direction. When the rotation guide member 31 rotates in the forward direction, the connecting member 30b connected to the holding member 30 is pressed against the groove portion 31a of the rotation guide member 31, causing the holding member 30 to rotate together with the rotation guide member 31.

As a result, the driver bit 2 held by the holding member 30 rotates the screw 200 in the forward direction (clockwise) to screw it into the object to be fastened. The control unit 100, in conjunction with the operation of rotating the driver bit 2 with the first drive unit 4 to screw the screw into the object to be fastened, moves the driver bit 2 forward with the second drive unit 5 based on the load on the bit rotation motor 40, the rotation speed of the bit rotation motor 40, the load on the bit movement motor 50, the rotation speed of the bit movement motor 50, etc., to cause the driver bit 2 to follow the screw being screwed into the object to be fastened.

As shown in FIG. 7, when the tip of the driver bit 2 protrudes from the ejection port 81a of the contact member 81 and reaches a predetermined operation end position P2, the control unit 100 stops driving the bit rotation motor 40 and reverses the bit movement motor 50. The control unit 100 may determine that the tip of the driver bit 2 has reached the operation end position P2 based on the rotation speed of the bit movement motor 50, or may vary the operation end position P2 based on the load on the bit rotation motor 40, the rotation speed of the bit rotation motor 40, the load on the bit movement motor 50, the rotation speed of the bit movement motor 50, etc.

When the bit moving motor 50 rotates in the other direction, that is, in the reverse direction, the pulley 52 rotates in the reverse direction, causing the wire 54 to be pulled out from the pulley 52. When the wire 54 is pulled out from the pulley 52, the second moving member 32c moves forward, causing the compressed biasing member 33 to expand, and push the second moving member 32c backward.

The second moving member 32c is pushed rearward by the biasing member 33 and is guided by the rotation guide member 31 to move rearward along the axial direction. When the second moving member 32c moves rearward, the first moving member 32a is pulled by the second moving member 32c via the bearing 32b, and moves rearward along the axial direction together with the second moving member 32c.

When the first moving member 32a moves rearward, the holding member 30 connected to the first moving member 32a by the connecting member 30b moves rearward along the axial direction of the driver bit 2, with the connecting member 30b being guided by the groove portion 31a of the rotation guide member 31.

As a result, the driver bit 2 held by the holding member 30 moves backward, and the tip of the driver bit 2 returns to the standby position P1. The moving member 32 is provided with a cushioning member 32d made of rubber or the like on the rear side of the second moving member 32c, which prevents the second moving member 32c from directly hitting the rear frame 10c when the second moving member 32c moves backward, thereby suppressing the generation of noise and damage. When the second moving member 32c is pushed backward by the biasing member 33 and the tip of the driver bit 2 returns to the standby position P1, the control unit 100 stops the rotation of the bit moving motor 50. When the trigger switch unit 90 is turned off, the control unit 100 rotates the screw feed motor 70 in one direction to lower the engagement unit 73. When the engaging portion 73 descends to a position where it engages with the next screw 200, the control unit 100 reverses the screw feed motor 70 to raise the engaging portion 73 and supply the next screw 200 to the supply passage 80.

The fastening tool 1 has a battery 12 removably attached to a battery attachment section 13 provided on a handle 11, and is equipped with a first drive section 4 that rotates a driver bit 2 with a bit rotation motor 40 driven by electricity supplied from the battery 12, and a second drive section 5 that moves the driver bit 2 back and forth along the axial direction with a bit movement motor 50 driven by electricity supplied from the battery 12. This eliminates the need to connect a hose, as with fastening tools driven by air pressure, improving workability.

The fastening tool 1 also includes a second drive unit 5 that moves the driver bit 2 back and forth along the axial direction, so that the screw can be fastened without moving the fastening tool 1 in a direction approaching the object to be fastened while the contact member 81 is in contact with the object to be fastened. This eliminates the need to move the tool body in a direction approaching the object to be fastened, as is the case with normal drill drivers and impact drivers, improving workability.

Furthermore, the second drive unit 5 uses the driving force of the bit movement motor 50 to press the screw engaged with the driver bit 2 against the object to be fastened, so that the force pressing the screw against the object to be fastened can be easily adjusted to be excessive or insufficient, and the screw can be pressed against the object to be fastened with the appropriate force.

The first drive unit 4 is provided at the rear, one side of the tool body 10, with the handle 11 in between, and the second drive unit 5 is provided at the front, the other side of the tool body 10, with the handle 11 in between. This allows the first drive unit 4 and the second drive unit 5, each of which has a motor and is relatively heavy, to be distributed in front of and behind the handle 11. Therefore, when holding the handle 11 in the hand and performing fastening work with the extension direction of the tool body 10 in a substantially horizontal orientation, the weight balance in front of and behind the handle 11 becomes approximately equal, improving workability.

Furthermore, the second drive unit 5 is positioned offset to the left side of the approximate center of the fastening tool 1 in the left-right direction, and the screw feed unit 7 is positioned such that the screw feed motor 70 is offset to the right side of the approximate center of the fastening tool 1 in the left-right direction. This results in an approximately equal weight balance between the left and right, improving workability.

As described above, in the fastening tool 1, the first drive unit 4 that rotates the driver bit 2 and the second drive unit 5 that moves the driver bit 2 back and forth along the axial direction are driven by independent motors. This simplifies the configuration compared to a configuration in which two operations are performed by a single drive source, eliminating the need for a drive force transmission mechanism or a mechanism for transmitting the drive force at a predetermined timing. Furthermore, the simplified configuration allows for a reduction in weight. Furthermore, the two operations can be linked by control.

In addition, by using the screw feed motor 70 as the drive source for the screw feed unit 7, it can be driven by electricity supplied from the battery 12, and does not require the supply of air pressure. Furthermore, by driving the screw feed unit 7 by a motor independent of the rotation and movement of the driver bit 2, the configuration can be simplified compared to a configuration in which two or three operations are performed by a single drive source. In addition, the linking of multiple operations can be controlled.

The screw feed unit 7 is configured to be detachable from the nose body 10f that constitutes the tool body 10 in a state where each part is unitized and assembled. This improves assembly and facilitates replacement during maintenance and inspection, as opposed to a configuration in which each part, such as the screw feed motor 70, is fixed independently to the tool body 10. In addition, the precision between each part can be improved compared to a configuration in which each part is fixed independently to the tool body 10. Furthermore, the nose body 10f to which the screw feed unit 7 is fixed is integral with or fixed to the front frame 10b that constitutes the tool body 10, so that the precision of the mounting position of the screw feed unit 7 relative to the tool body 10 can be improved. In addition, the nose body 10f constitutes a part of the injection passage 80 through which the driver bit 2 passes, so that the precision of the mounting position of the screw feed unit 7 relative to the injection passage 80 can be improved.

Figures 9A and 9B are perspective views showing an example of the operation of attaching and detaching the driver bit in the fastening tool of this embodiment. Next, the operation of attaching and detaching the driver bit 2 will be explained with reference to each figure.

As shown in FIG. 1, in the fastening tool 1, the tip of the driver bit 2 located in the standby position P1 is located deep inside the nose portion 8 and is not exposed to the injection port 81a of the contact member 81. Therefore, when replacing the driver bit 2, the nose portion 8 is detached.

To attach or detach the nose portion 8, first, the screw 87 is removed. By removing the screw 87, the nose portion 8 can be removed from the fastening tool 1 as shown in FIG. 9B. The nose portion 8 is configured to be detachable from the tool body 10 with each component assembled, and the contact member 81 covering the front end of the tool body 10 and the components constituting the injection port 81a are removed as a unit. When the nose portion 8 is removed from the front frame 10b constituting the tool body 10, the injection passage component 80a, which is a component on the nose portion side 8, is removed from the injection passage component 80b of the nose body portion 10f fixed to the tool body 10, and the injection passage 80 is exposed.

As a result, the front end of the rotary guide member 31 is exposed at the front end of the tool body 10, and the driver bit 2 is exposed from the opening at the front end of the rotary guide member 31. Therefore, the driver bit 2 can be removed from the holding member 30 by grasping the driver bit with a tool such as pliers and pulling it.

The driver bit 2 is attached by inserting the driver bit 2 through the opening of the rotary guide member 31 and pushing it into the opening 30a of the holding member 30, so that the driver bit 2 is held by the holding member 30. The nose portion 8 is then attached to the front end of the tool body 10, and the screw 87 is tightened to fix the nose portion 8 to the tool body 10.

In addition, if the pulley 52 does not rotate even when an external force is applied to the pulley 52 when the bit moving motor 50 is stopped due to the reduction ratio of the reducer 51 of the second drive unit 5, a bit exchange mode may be provided in which the rotation of the bit moving motor 50 is stopped when the moving member 32 is moved to an exchange position where the tip of the driver bit 2 protrudes a predetermined amount from the rotation guide member 31.

The nose portion 8 is configured so that each part constituting the injection passage 80, the contact member 81, and the contact arm 82 can be attached and detached to the tool body 10 in a unitized and assembled state. This improves assembly ease, as opposed to a configuration in which each part, such as the contact arm 82, is fixed independently to the tool body 10. Also, compared to a configuration in which each part is fixed independently to the tool body 10, the precision between each part can be improved. Furthermore, the contact switch section 84, which requires wiring, is attached to the tool body 10, eliminating the need to connect or disconnect wiring.

<Modifications of the fastening tool according to the present embodiment>
FIG. 10A is a side cross-sectional view showing a modified example of the fastening tool of the present embodiment, FIG. 10B is a side cross-sectional view showing another modified example of the fastening tool of the present embodiment, and FIG. 11 is a block diagram showing a modified example of the fastening tool of the present embodiment.

As described above, the fastening tool 1 includes a second drive unit 5 that moves the driver bit 2 forward and backward along the axial direction, and the second drive unit 5 is driven by a bit moving motor 50. The moving member 32 connected by a wire 54 to the pulley 52 driven and rotated by the bit moving motor 50 and the holding member 30 connected to the moving member 32 move forward along the axial direction of the driver bit 2 along the rotating guide member 31. This allows the amount of movement (advancement) of the driver bit 2 to be controlled by controlling the amount of rotation of the bit moving motor 50. That is, by rotating the bit moving motor 50 in conjunction with the rotation of the bit rotation motor 40 that rotates the driver bit 2 in the direction to fasten the screw 200, the amount of advancement of the driver bit 2 that advances following the screw 200 as the screw 200 is fastened can be controlled by the amount of rotation of the bit moving motor 50, and the stop position along the axial direction of the driver bit 2 can be controlled.

Figures 12A to 12C are cross-sectional views showing the fastening state of the screw. Figure 12A shows the head 201 of the screw 200 in a so-called flush state, neither floating above nor embedded in the surface of the object 202 to be fastened. Figure 12B shows the head 201 of the screw 200 in a state floating above the object 202 to be fastened. Figure 12C shows the head 201 of the screw 200 in a state embedded in the object 202 to be fastened.

In the fastening tool 1, when the tip of the driver bit 2 reaches the operation end position P2, if the screw 200 is a flat head screw, it is preferable that the advancement amount of the driver bit 2 is set so that the surface of the head 201 of the screw 200 is flush with the surface of the object 202 to be fastened, as shown in Fig. 12A. Note that the screw 200 is not limited to a flat head screw, and if it is a pan head screw, bind, truss screw, or the like, it is preferable that the advancement amount of the driver bit 2 is set so that the seat surface of the head 201 of the screw 200 does not come into contact with the surface of the object 202 to be fastened, and the head 201 of the screw 200 does not float above the object 202 to be fastened.

When the tip of the driver bit 2 reaches the operation end position P2, if the head 201 of the screw 200 is floating above the object 202 to be fastened as shown in FIG. 12B, the advancement amount of the driver bit 2 is increased to advance the operation end position P2. On the other hand, if the head 201 of the screw 200 is embedded in the object 202 to be fastened as shown in FIG. 12C, the advancement amount of the driver bit 2 is decreased to move the operation end position P2 backward.

Therefore, a setting unit 110 is provided to set the advance amount of the driver bit 2. The setting unit 110 is an example of a setting means, and is configured to allow multiple setting values to be selected, or any setting value to be selected steplessly. The setting unit 110 is configured such that the setting value is selected with a rotary dial, for example, as shown in FIG. 10A.

In the case of a configuration with the above-mentioned rotary dial, among the methods of providing a dedicated setting means for setting the amount of movement (advancement) of the driver bit 2, a potentiometer whose resistance value changes depending on the rotation angle of the shaft to which the dial is connected, or a rotary encoder that outputs pulses according to the rotation angle, etc., can be used as a means for converting the operator's operation into an electrical signal. The control unit 100 reads these voltage values and the number of pulses, and sets the number of rotations (amount of rotations) of the bit movement motor 50, which determines the amount of movement (advancement) of the driver bit 2.

When both the contact switch unit 84, which is activated when pressed by the contact arm 82, and the trigger switch unit 90, which is activated by operating the trigger 9, are turned on and the conditions for starting screw tightening are met, the bit movement motor 50 rotates a set amount of rotation starting from the standby position P1, which is the initial position of the driver bit 2, and then stops or reverses the rotation, thereby controlling the operation end position P2 and adjusting the tightening depth.

Also, as shown in FIG. 10B, the setting unit 110 may be configured so that the setting value is selected by a button. In a method using a switch that is activated by pressing, such as a button, a method can be considered in which, for example, multiple tact switches (momentary switches), two in this example, are used to set the number of rotations (amount of rotations) of the bit moving motor 50 according to the switch that is pressed. In this method, once the power to the tool body is cut off, the previous setting value becomes unknown the next time the power is turned on, so it is also possible to store the setting value using a memory element such as an EEPROM.

The setting unit 110 may be a lever-type switch or a touch panel. The setting unit 110 may also be a combination of multiple setting means, for example, a combination of the dial method and the switch method described above. In this case, the amount of tightening may be adjusted by operating the dial, and the amount of tightening may be set deeper by operating the switch when it is necessary to temporarily tighten the screw at an angle, such as when tightening a corner.

Furthermore, the setting unit 110 may be configured to display the selected setting value by a method of indicating the current value with a label or engraving, or a method of indicating the current value with an LED, etc., so that the operator can easily grasp the current setting value. Note that, in order to prevent erroneous judgment of the setting due to noise, etc., the setting signal may be detected only when the bit moving motor 50 is stopped. In addition, since it is possible that the potentiometer may malfunction and indicate an abnormal voltage outside the normal operating range, it is possible to not use abnormal values and to notify the operator of the malfunction with an LED, buzzer, etc.

In a configuration in which the advancement amount of the driver bit 2 is adjusted mechanically, such as by moving the position of a stopper, a setting unit for moving the position of the stopper may be provided near the nose portion 8. In contrast, in the fastening tool 1 of this embodiment, the amount of movement (advancement amount) of the driver bit 2 can be electrically controlled by controlling the amount of rotation of the bit movement motor 50. Therefore, there are fewer restrictions on the location where the setting unit 110 is provided. Therefore, in the example of Figures 10A and 10B, the setting unit 110 is provided on one side of the battery attachment portion 13 provided at the bottom of the handle 11. Note that when the handle 11 is held with the right hand, the setting unit 110 is operated with the left hand, so it is preferable to provide the setting unit 110 on the left side of the battery attachment portion 13.

Figure 13 is a plan view showing an example of a setting unit. The setting unit 110 shown in Figure 13 is provided in the fastening tool 1 shown in Figure 10B, and includes a button 110a for selecting a setting value that gradually decreases the advance amount of the driver bit 2, and a button 110b for selecting a setting value that gradually increases the advance amount of the driver bit 2.

The setting unit 110 also includes a guide diagram 110a1 to allow visual recognition of the setting value selected by operating the button 110a. The guide diagram 110a1 may be provided on the button 110a or in the vicinity of the button 110a. Similarly, the setting unit 110 includes a guide diagram 110b1 to allow visual recognition of the setting value selected by operating the button 110b. The guide diagram 110b1 may be provided on the button 110b or in the vicinity of the button 110b.

The setting unit 110 further includes lamps 110c that display the selected setting value. The lamps 110c are an example of a display unit, and the selected setting value is displayed by the number of lamps 110c that are lit. For example, to decrease the amount of advancement of the driver bit 2, the number of lit lamps 110c is decreased, and to increase the amount of advancement of the driver bit 2, the number of lit lamps 110c is increased. The color of the lamps 110c may also be changed depending on the setting value.

In order to set the movement amount (advance amount) of the driver bit 2, a contact switch unit 84 or a trigger switch unit 90 may be used as the setting means, in addition to the method of providing a dedicated setting means. In the method of using existing operating means such as the contact switch unit 84 or the trigger switch unit 90 as the setting means, the number of rotations (amount of rotations) of the bit moving motor 50 can be set by performing a predetermined setting operation of the contact arm 82 or the trigger 9 that is different from the operation of performing a normal fastening operation. For example, if the contact arm 82 is not operated and the trigger 9 is pulled and released a predetermined number of times within a predetermined time, it is determined that this is a setting operation for setting the number of rotations (amount of rotations) of the bit moving motor 50. Specifically, it is possible to adjust the fastening depth step by step each time a predetermined operation, such as quickly operating only the trigger 9 three times, is repeated.

By using existing operating means such as the contact switch unit 84 and trigger switch unit 90 as the setting means, a separate operating means or setting means for adjusting the tightening amount is not required, which allows the tool body to be made smaller and less costly.

Figure 14 is a flow chart showing an example of the operation of a fastening tool according to a modified example of this embodiment. Next, the operation of setting the advance amount of the driver bit 2 and fastening the tool will be described with reference to each figure.

In step SA1 of FIG. 14, the control unit 100 sets the amount of rotation of the bit movement motor 50 that determines the amount of advancement of the driver bit 2 based on the setting value selected by the setting unit 110. When the contact member 81 is pressed against the fastening object, the contact switch unit 84 is pressed by the contact arm 82, the contact switch unit 84 is turned on in step SA2, the trigger 9 is operated, and the trigger switch unit 90 is turned on in step SA3, the control unit 100 drives the bit movement motor 50 of the second drive unit 5 in step SA4 and drives the bit rotation motor 40 of the first drive unit 4 in step SA5.

When the bit movement motor 50 is driven to rotate in one direction, the forward direction, the moving member 32 connected to the pulley 52 by the wire 54 and the holding member 30 connected to the moving member 32 move forward along the axial direction of the driver bit 2 along the rotating guide member 31.

As a result, the driver bit 2 held by the holding member 30 moves forward and engages with the screw 200 supplied to the injection port 81a of the nose portion 8, moving the screw 200 forward and pressing it against the object to be fastened.

When the bit rotation motor 40 is driven to rotate in one direction, the forward direction, the holding member 30 rotates together with the rotation guide member 31.

As a result, the driver bit 2 held by the holding member 30 rotates the screw 200 in the forward direction (clockwise) to screw it into the object to be fastened. The control unit 100, in conjunction with the operation of rotating the driver bit 2 with the first drive unit 4 to screw the screw into the object to be fastened, moves the driver bit 2 forward with the second drive unit 5 based on the load on the bit rotation motor 40, the rotation speed of the bit rotation motor 40, the load on the bit movement motor 50, the rotation speed of the bit movement motor 50, etc., to cause the driver bit 2 to follow the screw being screwed into the object to be fastened.

When the amount of rotation of the bit moving motor 50 reaches the set value selected by the setting unit 110 in step SA6 and the tip of the driver bit 2 reaches the set operation end position P2, the control unit 100 stops driving the bit rotation motor 40 in step SA7 and reverses the bit moving motor 50 in step SA8.

When the bit moving motor 50 rotates in the other direction, that is, in the reverse direction, the wire 54 is pulled out from the pulley 52, and the moving member 32 is pushed backward by the biasing member 33, and the moving member 32 and the holding member 30 connected to the moving member 32 move backward along the axial direction of the driver bit 2 along the rotating guide member 31.

When the bit moving motor 50 rotates in reverse to the initial position where a predetermined amount of wire 54 is pulled out from the pulley 52 in step SA9, the control unit 100 stops the reverse rotation of the bit moving motor 50 in step SA10.

This causes the driver bit 2 held by the holding member 30 to move backward, and the tip of the driver bit 2 returns to the standby position P1.

In the fastening tool 1, the amount of movement (advancement) of the driver bit 2 can be controlled by controlling the amount of rotation of the bit movement motor 50. This allows for highly accurate adjustment of the tip position of the driver bit 2 with a simple configuration, compared to a configuration in which the amount of advancement of the driver bit 2 can be adjusted mechanically, such as by moving the position of a stopper. Therefore, as shown in FIG. 12B, the head 201 of the screw 200 is prevented from floating off the object to be fastened 202, or from sinking too far into the object to be fastened 202, as shown in FIG. 12C, and can be made to have a so-called flat state as shown in FIG. 12A, resulting in a beautiful finish after the fastening operation.

Figures 15A to 15D are perspective views showing modified examples of the installation position of the setting unit. As described above, in the fastening tool 1 of this embodiment, the amount of movement (advancement) of the driver bit 2 can be electrically controlled by controlling the amount of rotation of the bit movement motor 50, so there are fewer restrictions on the location where the setting unit 110 is provided.

In FIG. 15A, the setting unit 110 is provided on the upper part of the battery attachment part 13, which is provided on the lower part of the handle 11. In FIG. 15B, the setting unit 110 is provided on the rear part of the battery attachment part 13. By providing the setting unit 110 on the upper part or on the rear part of the battery attachment part 13, near the center in the left-right direction, the setting unit 110 can be operated regardless of the dominant hand holding the handle 11.

Furthermore, the setting unit 110 may be provided on the tool body 10 side, and in FIG. 15C, the setting unit 110 is provided on the side of the tool body 10. When the handle 11 is held in the right hand, the setting unit 110 is operated with the left hand, so it is preferable that the setting unit 110 is provided on the left side of the tool body 10.

In addition, in FIG. 15D, the setting unit 110 is provided at the rear of the tool body 10, in this example, at the rear of the cover part 43 that covers the first drive unit 4. By providing the setting unit 110 near the center in the left-right direction at the rear of the tool body 10, it is possible to operate the setting unit 110 regardless of the dominant hand holding the handle 11. The setting unit 110 may also be provided at the top of the tool body 10.

In this way, the amount of movement along the axial direction of the driver bit 2 can be set using an electrical signal, so there are fewer restrictions on the placement of the setting unit 110, and it is easy to optimize the adjustment of the tightening depth while taking into account its operability.

1: Fastening tool, 10: Tool body, 10a: Case, 10b: Front frame, 10c: Rear frame, 10d: Connecting member, 10e: Screw, 10f: Nose body, 11: Handle, 12: Battery, 13: Battery attachment, 2: Driver bit, 3: Bit holding portion, 30: Holding member, 30a: Opening, 30b: Connecting member, 31: Rotation guide member, 31a: Groove portion, 32: Moving member (transmission member), 32a: First moving member, 32b: Bearing, 32c: Second moving member, 33: Pressing member, 4: First driving portion, 40: Bit rotation motor (first motor), 40a: Shaft, 41: Reducer, 41a: Shaft, 42: Bearing, 5: Second driving portion, 50: Bit moving motor (motor, second 2 motor), 50a...shaft, 51...reduction gear, 51a...shaft, 52...pulley (transmission member), 53...bearing, 54...wire (transmission member), 6...screw storage section, 7...screw feed section, 70...screw feed motor, 71...pinion gear (screw feed transmission section), 72...rack gear (screw feed transmission section), 73...engagement section, 74...subframe, 75, 76...screw, 8...nose section, 80...ejection passage, 80a, 80b...ejection passage configuration section, 81...contact member, 81a...ejection port, 82...contact arm, 83...adjustment section, 84...contact switch section, 85...screw, 86...subframe, 87...screw, 88...cover member, 9...trigger, 90...trigger switch section, 100...control section, 110...setting section

Claims (3)

A screw storage section in which screws are stored;
A screw feed unit feeds the screw stored in the screw storage unit to an injection passage through which a driver bit passes,
The screw feed unit includes a screw feed motor and
An engagement portion that engages with the screw;
a screw feed transmission unit that transmits a driving force of the screw feed motor to the engagement unit ,
The screw feed section is a unit in which the screw feed motor, the engagement section, and the screw feed transmission section are integrally assembled, and the unit is attached to a tool body ,
The screw feed transmission portion is supported so that a portion connected to the engagement portion can reciprocate along a screw feeding direction . a bit holding portion that holds a driver bit that engages with the screw fed by the screw feed portion in a rotatable and axially movable manner;
a first driving unit having a first motor that rotates the driver bit held by the bit holding unit;
The fastening tool according to claim 1 , further comprising: a second drive unit having a second motor for axially moving the driver bit held by the bit holding unit . The fastening tool according to claim 2 , further comprising a battery mounting portion to which a battery for supplying electricity to the screw feed motor, the first motor, and the second motor is attached .