JP2023042386A - fastening tool - Google Patents

Abstract

To provide a fastening tool that is enabled to control an operation of moving a driver bit in a direction in which the bit approaches an object to be fastened on the basis of the presence or absence of a screw.SOLUTION: A fastening tool 1 comprises: a bit holding part 3 that holds a driver bit 2 attachably and detachably and can rotate in a circumferential direction of the driver bit 2 and move in an axial direction of the driver bit; a bit rotating motor 40 that rotates the bit holding part 3; a bit moving motor 50 that moves the bit holding part 3 along the axial direction; and a control part 100 that controls a position along the axial direction of the bit holding part 3 at the rotation amount of the bit moving motor 50. The control part 100 determines the presence or absence of a screw on the basis of either or both of a load acting on the bit rotating motor 40 rotated in one fastening direction of the screw or a load acting on the bit rotating motor 50 rotated in one direction in which the bit holding part 3 is moved in a direction in which the part approaches an object to be fastened, and when determining that the screw is absent, stops the rotation of the bit rotating motor 40 and of the bit moving motor 50.SELECTED DRAWING: Figure 1A

Description

TECHNICAL FIELD The present invention relates to a fastening tool that engages a screw with a driver bit, presses the screw against an object to be fastened with the driver bit, and rotates the driver bit to screw the screw.

A tool called a portable driving tool is known that uses the air pressure of compressed air supplied from an air compressor or the combustion pressure of gas to sequentially drive out connecting fasteners loaded in a magazine from the tip of a driver guide. there is

As a tool that rotates a bit to tighten a screw and moves the bit in the direction of screw tightening, conventionally, a pneumatic screw driver has been proposed in which the bit is rotated by an air motor and moved in the direction of screw tightening by air pressure. (See, for example, Patent Document 1).

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

Patent No. 5262461 Patent No. 6197547

In both a screwing machine that uses air pressure and a screwing machine that drives a screw with the force of a spring, the driver bit moves toward the object to be fastened even if there is no screw, and the driver bit collides with the object to be fastened. It was possible.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fastening tool capable of controlling the movement of a driver bit in a direction to approach an object to be fastened based on the presence or absence of a screw. and

In order to solve the above-described problems, the present invention provides a bit holding portion that detachably holds a driver bit and is rotatable in the circumferential direction and movable in the axial direction of the driver bit; A motor that moves the holding part along the axial direction, and a control part that controls the position of the bit holding part along the axial direction by the amount of rotation of the motor. It is a fastening tool that stops the rotation of the motor based on the load applied to the motor that is rotated in one direction to move in the approaching direction.

In the present invention, when it is determined that there is no screw based on the load applied to the motor, the rotation of the motor is stopped and the forward movement of the driver bit attached to the bit holding portion is suppressed.

In the present invention, it is possible to control the movement of the driver bit in the direction toward the object to be fastened based on the presence or absence of the screw.

FIG. 2 is a side cross-sectional view showing an example of the internal structure of the fastening tool of the present embodiment; FIG. 2 is a top cross-sectional view showing an example of the internal structure of the fastening tool of the present embodiment; It is a front sectional view showing an example of the internal structure of the fastening tool of this embodiment. Fig. 2 is an exploded perspective view showing an example of the internal structure of the fastening tool of the present embodiment; 1 is an external perspective view showing an example of a fastening tool according to this embodiment; FIG. It is a perspective view showing an example of the important section composition of the fastening tool of this embodiment. It is a perspective view showing an example of the important section composition of the fastening tool of this embodiment. It is a cross-sectional perspective view which shows an example of a principal part structure of the fastening tool of this Embodiment. It is a cross-sectional perspective view which shows an example of a principal part structure of the fastening tool of this Embodiment. It is a cross-sectional perspective view which shows an example of a principal part structure of the fastening tool of this Embodiment. FIG. 2 is a top cross-sectional view showing an example of the main configuration of the fastening tool of the present embodiment; FIG. 2 is a top cross-sectional view showing an example of the internal structure of the fastening tool of the present embodiment; FIG. 2 is a top cross-sectional view showing an example of the internal structure of the fastening tool of the present embodiment; FIG. 4 is a cross-sectional view showing an example of an attachment/detachment holding mechanism; FIG. 4 is a cross-sectional view showing an example of an attachment/detachment holding mechanism; FIG. 3 is a perspective view showing an example of a detachable holding mechanism; FIG. 3 is a perspective view showing an example of a detachable holding mechanism; It is a perspective view which shows an example of the screw feed part of this Embodiment, and a nose part. It is the perspective view seen from the back which shows an example of the fastening tool of this embodiment. It is the perspective view seen from the back which shows an example of the fastening tool of this embodiment. It is the perspective view seen from the back which shows an example of the fastening tool of this embodiment. It is a perspective view which shows an example of a setting part. It is a block diagram showing an example of a fastening tool of the present embodiment. FIG. 4 is a side cross-sectional view showing an example of the operation of the fastening tool of the present embodiment; FIG. 4 is a cross-sectional top view showing an example of the operation of the fastening tool of the present embodiment; 4 is a flow chart showing an example of the operation of the fastening tool of the present embodiment; It is a sectional view showing a fastening state of a screw. It is a sectional view showing a fastening state of a screw. It is a sectional view showing a fastening state of a screw. FIG. 10 is an explanatory diagram showing an example of an operation of setting standby positions of the holding member and the moving member in the first initialization operation; FIG. 10 is an explanatory diagram showing an example of an operation of setting standby positions of the holding member and the moving member in the first initialization operation; FIG. 10 is an explanatory diagram showing an example of an operation of setting standby positions of the holding member and the moving member in the first initialization operation; FIG. 10 is an explanatory diagram showing an example of an operation of setting standby positions of the holding member and the moving member in the first initialization operation; FIG. 10 is an explanatory diagram showing an example of an operation of moving the holding member and the moving member to the standby position in the second initialization operation; FIG. 10 is an explanatory diagram showing an example of an operation of moving the holding member and the moving member to the standby position in the second initialization operation; FIG. 10 is an explanatory diagram showing an example of an operation of moving the holding member and the moving member to the standby position in the second initialization operation; 7 is a flow chart showing an example of an operation of selecting a first initialization operation and a second initialization operation; 7 is a flow chart showing a modification of the operation of the fastening tool of the present embodiment; 5 is a graph showing the relationship between the output of the contact switch section and the control of the bit rotating motor and the bit moving motor; 9 is a flow chart showing another modification of the operation of the fastening tool of the present embodiment; It is a graph which shows the relationship between load and control of a bit rotating motor. It is a graph which shows the relationship between load and control of a bit rotating motor. 9 is a flow chart showing another modification of the operation of the fastening tool of the present embodiment; 4 is a graph showing the relationship between the rotational speeds of a bit rotating motor and a bit moving motor under feedback control; 4 is a graph showing the relationship between the moving speed of a screw caused by rotation of a bit rotating motor under feedback control and the moving speed of a driver bit caused by the bit moving motor. 9 is a flow chart showing another modification of the operation of the fastening tool of the present embodiment; It is a graph which shows the relationship between load and control of a bit movement motor. It is a graph which shows the relationship between load and control of a bit movement motor. 9 is a flow chart showing another modification of the operation of the fastening tool of the present embodiment;

Embodiments of the fastening tool of the present invention will be described below with reference to the drawings.

<Configuration example of the fastening tool of the present embodiment>
FIG. 1A is a side sectional view showing an example of the internal structure of the fastening tool of the present embodiment, FIG. 1B is a top sectional view showing an example of the internal structure of the fastening tool of the present embodiment, and FIG. 1 is a front cross-sectional view showing an example of the internal structure of a fastening tool in the form of . Moreover, FIG. 2A is an exploded perspective view showing an example of the internal structure of the fastening tool of this embodiment, and FIG. 2B is an external perspective view showing an example of the fastening tool of this embodiment.

The fastening tool 1 of this embodiment includes a bit holding portion 3 that holds a driver bit 2 rotatably and axially movably, and a first bit holding portion 3 that rotates the driver bit 2 held by the bit holding portion 3. A drive unit 4 and a second drive unit 5 for moving the driver bit 2 held by the bit holding unit 3 in the axial direction are provided.

In addition, the fastening tool 1 is pressed against a screw storage portion 6 that stores the screw 200, a screw feeding portion 7 that feeds the screw stored in the screw storage portion 6, and a fastening object to which the screw 200 is to be fastened. It has a nose part 8 through which screws are injected.

Furthermore, the fastening tool 1 comprises a tool body 10 and a handle 11 . The fastening tool 1 also includes a battery attachment portion 13 to which the battery 12 is detachably attached at the end of the handle 11 .

The fastening tool 1 has a tool body 10 extending in one direction along the axial direction of the driver bit 2 indicated by arrows A1 and A2, and a handle 11 extending in the other direction crossing the extending direction of the tool body 10. do. In the fastening tool 1, the direction in which the tool body 10 extends, that is, the axial direction of the driver bit 2 indicated by arrows A1 and A2 is defined as the front-rear direction. In the fastening tool 1, the direction in which the handle 11 extends is the vertical direction. Further, in the fastening tool 1, the direction orthogonal to the extension direction of the tool body 10 and the extension direction of the handle 11 is defined as the left-right direction.

The first drive unit 4 is provided on one side of the tool body 10, ie, rear, with the handle 11 interposed therebetween. Also, the second drive unit 5 is provided on the other side of the tool main body 10 , which is the front side, with the handle 11 interposed therebetween.

A plurality of screws 200 are connected by a connecting band, and the screw accommodating portion 6 accommodates a spirally wound connecting screw.

3A and 3B are perspective views showing an example of the main configuration of the fastening tool of the present embodiment, and FIGS. 4A to 4C are cross-sectional perspective views showing an example of the main configuration of the fastening tool of the present embodiment. 5 is a cross-sectional top view showing an example of the main configuration of the fastening tool according to the present embodiment, showing details of the bit holding portion 3 and the first driving portion 4. As shown in FIG. Next, the bit holding unit 3 and the first driving unit 4 will be described with reference to each drawing.

The bit holding portion 3 is an example of a tip tool holding portion. , a rotation guide member 31 that rotates together with the holding member 30, a moving member 32 that moves the holding member 30 in the front and rear direction along the rotation guide member 31, and a moving member 32 indicated by an arrow A biasing member 33 that biases backward indicated by A2 is provided.

The holding member 30 has an outer diameter slightly smaller than the inner diameter of the rotation guide member 31 and is configured by, for example, a cylindrical member that can be inserted inside the rotation guide member 31 . The holding member 30 is provided with an opening 30 a having a shape matching the cross-sectional shape of the driver bit 2 at the front end portion along the axial direction of the driver bit 2 . The holding member 30 has a detachable holding mechanism 30c for detachably holding the driver bit 2 in the opening 30a. The holding member 30 has an opening 30a exposed inside the rotation guide member 31, and the driver bit 2 is detachably inserted into the opening 30a.

The rotation guide member 31 extends along the extending direction of the tool body 10 , that is, along the longitudinal direction indicated by arrows A<b>1 and A<b>2 along the axial direction of the driver bit 2 . The rotation guide member 31 has a cylindrical shape in which the holding member 30 is inserted, and the front end portion of the rotation guide member 31 is attached to a metal front frame 10b provided on the front side of a resin case 10a that constitutes the exterior of the tool body 10. It is rotatably supported via a bearing 34a, which is an example of . Further, the rotation guide member 31 is connected to the first driving section 4 at the rear end.

The rotation guide member 31 has grooves 31a extending in the front-rear direction indicated by arrows A1 and A2 along the axial direction of the driver bit 2, and formed at two diametrically opposed side portions. The rotation guide member 31 penetrates the holding member 30 in the radial direction and is connected to the holding member 30 via the connecting member 30b by inserting the connecting member 30b protruding from both sides of the holding member 30 into the groove 31a.

The holding member 30 is provided with a hole passing through in the direction perpendicular to the rotating direction of the driver bit 2, and the connecting member 30b is inserted into this hole and fixed with a pin 30f. The connecting member 30b is configured by a tubular member having an oval cross-sectional shape.

The connecting member 30b has an elliptical longitudinal direction along the extension direction of the groove portion 31a parallel to the axial direction of the driver bit 2 indicated by arrows A1 and A2, and an elliptical transverse direction along the arrow B1 and the axial direction of the driver bit 2. It is a direction orthogonal to the extending direction of the groove portion 31a indicated by the direction B2, that is, the direction along the rotation direction of the rotation guide member 31. As shown in FIG. The width of the connecting member 30b in the lateral direction of the oval shape, that is, the width along the rotation direction of the rotation guide member 31 is slightly smaller than the width of the groove portion 31a along the same direction.

As a result, the connecting member 30b inserted in the groove portion 31a is supported by the groove portion 31a so as to be movable along the axial direction of the rotation guide member 31. As shown in FIG. Further, the movement of the connecting member 30b in the rotational direction with respect to the rotation guide member 31 is restricted between one side surface and the other side surface of the groove portion 31a along the extending direction of the groove portion 31a. Therefore, when the rotation guide member 31 rotates, the connecting member 30b is pushed by one side surface or the other side surface of the groove 31a according to the rotation direction of the rotation guide member 31, and is rotated from the rotation guide member 31. receive circumferential force.

Therefore, when the rotation guide member 31 rotates, the connecting member 30b is pushed by the groove 31a of the rotation guide member 31, so that the holding member 30 rotates together with the rotation guide member 31. As shown in FIG. The connecting member 30 b of the holding member 30 is guided by the groove 31 a of the rotation guide member 31 and moves in the longitudinal direction along the axial direction of the driver bit 2 .

The moving member 32 is an example of a transmission member. A first moving member 32a that rotates together with the holding member 30 and moves the holding member 30 in the front-rear direction along the rotation guide member 31, and a bearing 32b. A second moving member 32c supported by the member 32a and pushing the first moving member 32a via a bearing 32b, and a buffer member 32d attached to the rear side of the second moving member 32c are provided.

The first moving member 32a has an inner diameter slightly larger than the outer diameter of the rotation guide member 31, and is composed of, for example, a cylindrical member that can be placed outside the rotation guide member 31. As shown in FIG. The first moving member 32a is connected to the holding member 30 via a connecting member 30b protruding from the groove 31a of the rotation guide member 31, and is supported so as to be movable along the axial direction of the rotation guide member 31. .

The bearing 32b is an example of a bearing, and is inserted between the outer circumference of the first moving member 32a and the inner circumference of the second moving member 32c. The first moving member 32a constitutes a bearing inner ring holding member that holds the inner ring of the bearing 32b, and the second moving member 32c constitutes a bearing outer ring holding member that holds the outer ring of the bearing 32b. The bearing 32b has an inner ring supported on the outer circumference of the first moving member 32a so as not to move in the rotational and axial directions, and an outer ring arranged on the inner circumference of the second moving member 32c so as not to move in the rotational and axial directions. Supported.

As a result, the second moving member 32c is connected to the first moving member 32a via the bearing 32b in a state in which movement in the longitudinal direction along the axial direction is restricted. Also, the second moving member 32c rotatably supports the first moving member 32a via a bearing 32b.

Therefore, the first moving member 32a is pushed by the second moving member 32c via the bearing 32b when the second moving member 32c moves in the longitudinal direction along the axial direction. Together with 32c, it moves in the longitudinal direction along the axial direction. Also, the first moving member 32 a is rotatable with respect to the second moving member 32 c that is non-rotatable with respect to the rotation guide member 31 .

The urging member 33 is composed of a coil spring in this example, and is provided between the front frame 10b provided on the front side of the case 10a of the tool body 10 outside the rotation guide member 31 and the second moving member 32c of the moving member 32. It abuts against a spring seat 32f which is interposed and arranged so as to contact the end surface of the outer ring of the bearing 32b. The urging member 33 is compressed by the movement of the moving member 32 in the forward direction indicated by the arrow A1, and applies a force to the moving member 32 that pushes the moving member 32 in the rearward direction indicated by the arrow A2.

The first drive unit 4 includes a bit rotation motor 40 driven by electricity supplied from the battery 12 and a speed reducer 41 . The bit rotation motor 40 is an example of a motor or a first motor. The first drive unit 4 has a configuration in which the speed reducer 41 uses a planetary gear, and the bit rotation motor 40 is arranged coaxially with the rotation guide member 31 and the holding member 30, and the driver bit 2 held by the holding member 30. be done.

The first drive unit 4 has a bit rotating motor 40 and a speed reducer 41 attached to a metal rear frame 10c provided on the rear side of the case 10a of the tool body 10. A shaft 41a of the speed reducer 41 is supported by the rear frame 10c via the . The rear end of the rotation guide member 31 is connected to the shaft 41a of the speed reducer 41, and the shaft 41a is supported by the rear frame 10c via the bearing 42, thereby supporting the bearing 42, which is an example of a bearing. It is rotatably supported through

The bit holding portion 3 and the first driving portion 4 are assembled integrally by connecting the front frame 10b and the rear frame 10c with a coupling member 10d extending in the front-rear direction. is fixed to the case 10a by screws 10e.

The bit holding part 3 is supported by a front frame 10b fixed to the front side of the case 10a of the tool body 10 via a bearing 34a at the front end of the rotation guide member 31. is supported by the rear frame 10c fixed to the rear side of the case 10a via the shaft 41a of the speed reducer 41 and the bearing 42. As shown in FIG. Therefore, the bit holding portion 3 is rotatably supported by the tool body 10 with the rotation guide member 31 .

Thereby, the first drive unit 4 rotates the rotation guide member 31 by the bit rotation motor 40 . When the rotation guide member 31 rotates, the holding member 30 holding the driver bit 2 rotates together with the rotation guide member 31 because the connecting member 30b is pushed by the groove 31a of the rotation guide member 31 .

The bit holding part 3 is provided with a guide member 32g on the second moving member 32c. The coupling member 10d is provided with a pair of guide wall portions 10g spaced apart by a distance slightly larger than the diameter of the guide member 32g. 10g faces the peripheral surface of the guide member 32g.

As a result, the guide member 32g is guided by the coupling member 10d, so that the second moving member 32c can move in the longitudinal direction indicated by the arrows A1 and A2 along the axial direction of the driver bit 2, and rotate. Rotation following the guide member 31 is restricted.

6A and 6B are top cross-sectional views showing an example of the internal structure of the fastening tool of the present embodiment, showing details of the second drive section 5. FIG. Next, the second driving section 5 will be described with reference to each drawing.

The second drive unit 5 includes a bit moving motor 50 driven by electricity supplied from the battery 12 and a speed reducer 51 . The bit moving motor 50 is an example of a motor or a second motor. A shaft 50a of the bit moving motor 50 is connected to a speed reducer 51, and a shaft 51a of the speed reducer 51 is connected to a pulley 52, which is an example of a transmission member. . A pulley 52 of the second driving portion 5 is supported by the tool body 10 via a bearing 53 . The second drive unit 5 is arranged such that the shaft 50 a of the bit moving motor 50 extends along the extending direction of the handle 11 .

In the second drive unit 5, one end of a linear wire 54, which is an example of a transmission member, is connected to a pulley 52, and the wire 54 is wound around the pulley 52 as the pulley 52 rotates. The other end of the wire 54 is connected to a wire connecting portion 32h provided on the second moving member 32c of the moving member 32. As shown in FIG.

As a result, the second driving section 5 rotates the pulley 52 by the bit moving motor 50 to wind the wire 54, thereby moving the second moving member 32c in the forward direction indicated by the arrow A1. In the bit holding part 3, the forward movement of the second moving member 32c pushes the first moving member 32a via the bearing 32b, and the first moving member 32a moves forward together with the second moving member 32c. Move forward along the axial direction. As the first moving member 32a moves forward, the holding member 30 connected to the first moving member 32a and the connecting member 30b moves forward, and the driver bit held by the holding member 30 moves forward. 2 moves forward as indicated by arrow A1.

The second drive unit 5 is offset to one side with respect to the approximate center of the fastening tool 1 in the left-right direction so that the tangential direction of the portion of the pulley 52 around which the wire 54 is wound is aligned with the extension direction of the rotation guide member 31 . placed. That is, the center of the pulley 52, in this example, the shaft 50a of the bit moving motor 50, is offset to one side with respect to the rotation guide member 31, and the wire 54 is wound around the pulley 52 when viewed from the axial direction of the pulley 52. The portion 52 a to be cut is arranged to overlap the rotation guide member 31 .

6A and 6B, the wire 54 between the pulley 52 and the second moving member 32c is parallel to the axial direction of the rotation guide member 31 in the radial direction of the pulley 52 and As shown in 1A, the pulley 52 and the like are arranged so as to be parallel to the axial direction of the rotation guide member 31 even in the axial direction of the bit moving motor 50 orthogonal to the radial direction of the pulley 52 .

Furthermore, when the wire 54 is wound around the pulley 52, the distance from the center of the pulley 52 to the wire 54 changes according to the number of turns. Change. Further, the angle between the direction in which the wire 54 extends between the pulley 52 and the second moving member 32c and the moving direction of the driver bit 2 along the axial direction of the rotation guide member 31 changes.

Therefore, the diameter and the like of the pulley 52 are set so that the amount of rotation α of the pulley 52 required to move the driver bit 2 by a predetermined amount is less than 360°.

As a result, when the pulley 52 winds the wire 54 in order to move the driver bit 2 by a predetermined amount, the wire 54 is not overlapped around the pulley 52 as shown in FIG. Inaccuracy in the amount of movement is suppressed. In addition, change in parallelism between the direction in which the wire 54 extends between the pulley 52 and the second moving member 32c and the moving direction of the driver bit 2 along the axial direction of the rotation guide member 31 is suppressed.

Therefore, the amount of rotation of the bit moving motor 50 and the amount of movement of the holding member 30 are in a one-to-one relationship over the entire movable range of the holding member 30, and the amount of rotation of the bit moving motor 50 is controlled. Thus, the amount of movement of the holding member 30 along the axial direction of the rotation guide member 31 can be controlled. That is, by controlling the amount of rotation of the bit moving motor 50, the amount of movement of the driver bit 2 attached to the holding member 30 can be controlled.

In addition, regardless of the winding amount of the wire 54, the tension applied to the wire 54 is always parallel to the moving direction of the driver bit 2 along the axial direction of the rotation guide member 31, so that the driver bit 2 moves and the driver bit 2 moves. It is possible to suppress a decrease in transmission efficiency of the force for pushing the screw 200 through the screw 200 .

As a result, the wire 54 between the pulley 52 and the second moving member 32c extends linearly along the moving direction of the moving member 32, increasing the load when the wire 54 is wound by the pulley 52, An increase in load when the wire 54 is pulled out from 52 is suppressed.

Since the wire 54 is flexible enough to be wound around the pulley 52, it cannot push the second moving member 32c to move the moving member 32 backward. Therefore, an urging member 33 is provided that applies a force to the moving member 32, which is compressed when the moving member 32 moves forward as indicated by the arrow A1, and pushes the moving member 32 in the rearward direction indicated by the arrow A2. As a result, the wire 54 is wound by the pulley 52 and the driver bit 2 is moved forward, so that the driver bit 2 can be moved backward after being advanced.

Further, the holding member 30 that holds the driver bit 2 is moved in the longitudinal direction with respect to the rotation guide member 31 by the engagement between the connecting member 30b provided in the holding member 30 and the groove 31a provided in the rotation guide member 31. It is possible to be supported and rotate together with the rotation guide member 31 .

Therefore, the bit rotating motor 40 is arranged coaxially with the rotation guide member 31, the holding member 30, and the driver bit 2 held by the holding member 30. A configuration in which the driver bit 2 is rotated and the driver bit 2 is moved back and forth can be realized.

In the configuration in which the bit rotating motor 40 is arranged coaxially with the driver bit 2, it is conceivable to use a feed screw to convert the rotating motion of the bit rotating motor 40 into the movement of the driver bit 2 in the front-rear direction. be done.

However, in the configuration using the feed screw, it is difficult to increase the movement speed of the driver bit 2 even if the rotation speed of the motor is increased because the amount of forward movement of the driver bit 2 per motor rotation cannot be increased.

In the fastening tool 1, it is necessary to increase the moving speed of the driver bit 2 in order to shorten the time required for the driver bit 2 to press the screw 200 against the fastening object. It is difficult to reduce the time required to press the screw 200 against the object to be fastened.

On the other hand, a holding member 30 holding the driver bit 2 is movably supported in the front-rear direction with respect to the rotation guide member 31, and the pulley 52 is rotated by the second driving section 5 to wind the wire 54, In the configuration in which the holding member 30 is moved forward, the moving speed of the driver bit 2 can be increased according to the rotational speed of the bit moving motor 50 . Therefore, the time required for pressing the screw 200 against the object to be fastened with the driver bit 2 can be shortened.

7A and 7B are cross-sectional views showing an example of the attachment/detachment holding mechanism, and FIGS. 8A and 8B are perspective views showing an example of the attachment/detachment holding mechanism, showing details of the attachment/detachment holding mechanism 30c. Next, the attachment/detachment holding mechanism 30c will be described with reference to each drawing.

The attachment/detachment holding mechanism 30c includes a ball 30d exposed in the opening 30a and a spring 30e that biases the ball 30d in the direction of exposing it in the opening 30a. The spring 30 e is composed of an annular plate spring and fitted around the outer circumference of the holding member 30 .

When the insertion portion 20 of the driver bit 2 is inserted into the opening 30a of the holding member 30, the attachment/detachment holding mechanism 30c causes the ball 30d pushed by the insertion portion 20 to spring in the direction in which the diameter of the annular spring 30e increases. The holding member 30 is retracted in the outer peripheral direction while deforming the holding member 30e.

When the insertion portion 20 of the driver bit 2 is inserted into the opening 30a of the holding member 30 until the groove portion 20a formed on the outer periphery of the insertion portion 20 faces the ball 30d, the ball 30d is biased by the spring 30e. fits into the groove 20a. As a result, the driver bit 2 is prevented from accidentally falling out of the holding member 30 .

Further, when a predetermined force or more is applied in the direction in which the driver bit 2 is removed from the holding member 30, the ball 30d is retracted while the spring 30e is deformed in the direction in which the diameter of the annular spring 30e increases. can be pulled out from the holding member 30 .

When the insertion portion 20 of the driver bit 2 is inserted into and extracted from the opening 30a of the holding member 30, the ball 30d is retracted in the outer peripheral direction of the holding member 30. As shown in FIG. Therefore, a space for retracting the balls 30d is required on the outer periphery of the holding member 30. As shown in FIG. On the other hand, the holding member 30 is inserted inside a cylindrical rotation guide member 31, and a space for retracting the balls 30d cannot be secured between the outer circumference of the holding member 30 and the inner circumference of the rotation guide member 31.

Further, in order to secure a space between the outer circumference of the holding member 30 and the inner circumference of the rotation guide member 31 for retracting the balls 30d, setting the difference in diameter between the holding member 30 and the rotation guide member 31 allows the driver bit 2 to move. Since the outer diameter of the holding member 30 cannot be reduced due to the fixed radial dimension, it is necessary to increase the outer diameter of the rotation guide member 31 . Therefore, the size of the device is increased.

On the other hand, the rotation guide member 31 is provided with a groove portion 31a for guiding the connecting member 30b. The groove portion 31 a penetrates from the inner peripheral side to the outer peripheral side of the rotation guide member 31 and extends in the axial direction of the rotation guide member 31 .

Therefore, the attachment/detachment holding mechanism 30 c is provided with the ball 30 d aligned with the position of the groove 31 a of the rotation guide member 31 . That is, in the holding member 30, the connecting member 30b and the ball 30d of the detachable holding mechanism 30c are provided coaxially along the axial direction of the rotation guide member 31. As shown in FIG. As a result, the attachment/detachment holding mechanism 30c allows the ball 30d to move toward the rotation guide member 31 regardless of whether the rotation guide member 31 and the holding member 30 rotate or when the holding member 30 moves in the axial direction with respect to the rotation guide member 31. is exposed to the groove portion 31a of .

Therefore, when the insertion portion 20 of the driver bit 2 is inserted into and removed from the opening 30a of the holding member 30, the ball 30d retreating in the outer peripheral direction of the holding member 30 enters the groove portion 31a of the rotation guide member 31. FIG.

Therefore, with the configuration in which the holding member 30 is inserted inside the cylindrical rotation guide member 31, a space for retracting the ball 30d of the attachment/detachment holding mechanism 30c can be secured. Further, by using the groove portion 31a into which the connecting member 30b is inserted as a space for retracting the ball 30d, the area of the opening provided in the rotation guide member 31 can be reduced and the strength can be ensured.

Furthermore, there is no need to secure a space between the outer circumference of the holding member 30 and the inner circumference of the rotation guide member 31 for the balls 30d to retreat by increasing the difference in diameter between the holding member 30 and the rotation guide member 31. can be suppressed.

FIG. 9 is a perspective view showing an example of the screw feeding portion and the nose portion of the present embodiment, showing details of the screw feeding portion 7 and the nose portion 8. As shown in FIG. Next, the screw feeding portion 7 and the nose portion 8 will be described with reference to each drawing.

The screw feeding portion 7 is connected to a screw feeding motor 70 , a pinion gear 71 attached to the shaft of the screw feeding motor 70 via a reduction gear, a rack gear 72 meshing with the pinion gear 71 , and a rack gear 72 . It has an engaging portion 73 that engages with a connecting screw sent from.

The screw feeder 7 supports a rack gear 72 so as to be vertically movable along the feeding direction of the connecting screw. In the screw feeder 7, the screw feed motor 70 rotates forward and backward, so that the engaging portion 73 that engages with the connecting screw moves vertically, and the connecting screw is fed.

The nose portion 8 is supplied with the screw 200 by the screw feeding portion 7, has an ejection passage 80 through which the driver bit 2 passes, and an ejection opening 81a communicating with the ejection passage 80, and a contact member 81 that contacts an object to be fastened. , a contact arm 82 that moves back and forth in conjunction with the contact member 81 , and an adjusting portion 83 that regulates the amount of movement of the contact arm 82 . Further, the nose portion 8 includes a cover member 88 that openably and closably covers the path through which the screw 200 passes from the screw housing portion 6 to the injection passage 80 .

In the fastening tool 1, each part constituting the injection passage 80, the contact member 81, and the contact arm 82 is assembled to form the nose portion 8, which is fixed to the front frame 10b and the nose body portion 10f that constitute the tool body 10. . The fastening tool 1 also includes a contact switch portion 84 that is pushed by the contact arm 82 to operate.

The nose portion 8 is supported so that the contact member 81 can move in the front-rear direction indicated by arrows A1 and A2, and the contact arm 82 moves in the front-rear direction in conjunction with the contact member 81 . In the nose portion 8, the contact member 81 is urged forward by an urging member (not shown), and the contact member 81 moved backward by being pressed against the object to be fastened is urged by the urging member to move forward. do.

The adjusting portion 83 adjusts the amount of movement of the contact arm 82 of the nose portion 8 until the contact member 81 is pressed against the object to be fastened and the contact arm 82 moves rearward and the contact switch portion 84 is actuated. The contact switch portion 84 is switched between the presence and absence of operation by being pushed by the contact arm 82 . The state in which the contact switch portion 84 is actuated by being pushed by the contact arm 82 is referred to as the ON state of the contact switch portion 84 .

Next, with reference to each figure, the configuration regarding the control and operation of the fastening tool 1 will be described. The fastening tool 1 includes a trigger 9 that receives an operation and a trigger switch section 90 that operates when the trigger 9 is operated. The trigger 9 is provided on the front side of the handle 11 and configured to be operable with the fingers of the hand holding the handle 11 . The trigger switch section 90 is actuated by being pushed by the trigger 9 .

The trigger switch part 90 is switched between the presence and absence of operation by being pushed by the trigger 9. In this example, the trigger switch part 90 is not operated because the trigger 9 is not operated and the trigger switch part 90 is not pushed by the trigger 9. The trigger switch portion 90 is turned off when the trigger switch 90 is pressed, and the trigger switch portion 90 is turned on when the trigger 9 is pressed by the trigger 9 and the trigger switch portion 90 is activated.

The fastening tool 1 operates the first drive section 4, the second drive section 5 and the screw based on the output of the trigger switch section 90 which is operated by the operation of the trigger 9 and the contact switch section 84 which is operated by being pushed by the contact member 81. A control unit 100 for controlling the feeding unit 7 is provided.

The control unit 100 is made up of a substrate on which various electronic components are mounted, and is provided in a substrate housing portion 111 provided on the back side of the screw housing portion 6 between the screw housing portion 6 and the handle 11 .

2. Description of the Related Art An electric power tool that is used by holding a handle is provided with a storage section in front of the handle for storing consumables such as screws. In order to allow the handle to be gripped by hand, a space for inserting fingers is required between the handle and the housing.

Therefore, the fastening tool 1 utilizes the space between the screw storage portion 6 and the handle 11 to provide the board storage portion 111 on the back side of the screw storage portion 6 .

2. Description of the Related Art Electric power tools that are used by holding a handle by hand have proposed a configuration in which a battery is attached to the lower portion of the handle and a circuit board is provided between the handle and the battery. With such a configuration, the vertical dimension of the power tool along the extension direction of the handle is increased.

On the other hand, by providing the board storage portion 111 on the back side of the screw storage portion 6, the increase in the vertical dimension of the fastening tool 1 along the extension direction of the handle 11 is suppressed. Further, since the screw housing portion 6 houses the spirally wound connecting screw, the surface of the screw housing portion 6 facing the handle 11 is substantially circular. As a result, the volume of the board storage portion 111 can be secured while suppressing the fastening tool 1 from becoming large.

10A to 10C are perspective views from the rear showing an example of the fastening tool according to the present embodiment, and FIG. 11 is a perspective view showing an example of the setting portion, showing details of the setting portion 110. FIG. Next, the setting unit 110 will be described with reference to each drawing.

The fastening tool 1 includes a second driving section 5 that moves the driver bit 2 in the longitudinal direction along the axial direction. A moving member 32 connected to a pulley 52 that rotates through a wire 54 and a holding member 30 connected to the moving member 32 move forward along the axial direction of the driver bit 2 along the rotation guide member 31. Configuration.

Thus, by controlling the amount of rotation of the bit moving motor 50, the moving amount (advance amount) of the driver bit 2 can be controlled. That is, by rotating the bit moving motor 50 in conjunction with the rotation of the bit rotating motor 40 that rotates the driver bit 2 in the direction of tightening the screw 200, the screw 200 is tightened and moved forward following the screw 200. The stop position of the driver bit 2 along the axial direction can be controlled by controlling the amount of advance of the driver bit 2 by controlling the amount of rotation of the bit moving motor 50 .

Therefore, the fastening tool 1 includes a setting section 110 for setting the advance amount of the driver bit 2 . The setting unit 110 is an example of setting means, and is configured so that an arbitrary setting value can be selected from a plurality of setting values, or an arbitrary setting value can be selected steplessly.

In this example, the setting unit 110 is configured such that a setting value is selected by an operation unit 110a configured with buttons. Further, the operation unit 110a may be configured to select a set value with a rotary dial. In addition, the setting unit 110 is selected by a method of indicating the current value with a label, a stamp, or the like, or a method of indicating the current value with the display unit 110b such as an LED, so that the operator can easily grasp the current setting value. A configuration for displaying the setting value may be provided.

The setting portions 110 are provided on both the left and right sides of the surface facing the handle 11 in the board storage portion 111 provided on the back side of the screw storage portion 6 .

Accordingly, when the fastening tool 1 is viewed from the rear, the setting portion 110 can be visually recognized from both the left and right sides of the handle 11 .

When the handle 11 is held by hand, the surface of the screw housing 6 facing the handle 11 faces the operator holding the fastening tool 1 . As a result, by providing the setting unit 110 on the side facing the handle 11 in the board storage unit 111 provided on the back side of the screw storage unit 6, the display unit 110b provided in the setting unit 110 is easily visible. . Therefore, it is possible to reduce the possibility that the operator misses the display. The contents displayed on the display unit 110b include, in addition to the setting value of the screw depth defined by the amount of advancement of the driver bit 2, the ON/OFF state of the power supply and selection from among various selectable operation modes. the operation mode, the presence or absence of screws, the remaining amount of screws, the presence or absence of abnormalities, and the like.

In addition, in a usage pattern in which the handle 11 is held by hand, the operation section 110a such as buttons provided on the setting section 110 is easily visible. Therefore, while holding the handle 11 with one hand, the user can operate the operating unit 110a with the other hand while viewing the operating unit 110a.

Furthermore, the substrates constituting the control unit 100 are stored in the substrate storage unit 111 . In this substrate, on the side facing the handle 11, by mounting switches and the like constituting the operation portion 110a and lamps and the like constituting the display portion 110b, the control portion 110 can be used for the setting portion 110 separately from the control portion 100. substrate can be omitted.

FIG. 12 is a block diagram showing an example of the fastening tool of this embodiment. As described above, the fastening tool 1 includes the second driving section 5 that moves the driver bit 2 in the longitudinal direction along the axial direction, and the second driving section 5 is driven by the bit moving motor 50 . A holding member 30 to which the driver bit 2 is attached is connected with a moving member 32 , and the moving member 32 is connected with a wire 54 to a pulley 52 driven by a bit moving motor 50 to rotate. The holding member 30 and the moving member 32 move forward along the rotation guide member 31 along the axial direction of the driver bit 2 .

Accordingly, the control unit 100 can control the amount of movement (advance amount) of the driver bit 2 by controlling the amount of rotation of the bit movement motor 50 . That is, by rotating the bit moving motor 50 in conjunction with the rotation of the bit rotating motor 40 that rotates the driver bit 2 in the direction of tightening the screw 200, the screw 200 is tightened and moved forward following the screw 200. The stop position of the driver bit 2 along the axial direction can be controlled by controlling the amount of advance of the driver bit 2 by controlling the amount of rotation of the bit moving motor 50 .

In addition, the setting unit 110 of the control unit 100 sets the rotation amount of the bit moving motor 50 that defines the advance amount of the driver bit 2 . Further, the control unit 100 controls the bit moving motor 50 of the second driving unit 5 and the bit moving motor 50 of the first driving unit 4 based on the combination of ON/OFF of the contact switch unit 84 and ON/OFF of the trigger switch unit 90 . It controls whether or not the rotary motor 40 is driven.

<Example of operation of the fastening tool according to the present embodiment>
13A is a side sectional view showing an example of the operation of the fastening tool of the present embodiment, FIG. 13B is a top sectional view showing an example of the operation of the fastening tool of the present embodiment, and FIG. 3 is a flow chart showing an example of the operation of the fastening tool in FIG.

In the stand-by state of the fastening tool 1, as shown in FIG. 1A, the tip of the driver bit 2 is positioned at the stand-by position P1 behind the injection passage 80, and the screw 200 can be supplied to the injection passage 80.

The control unit 100 sets the amount of rotation of the bit moving motor 50 that defines the advance amount of the driver bit 2 based on the setting value selected by the setting unit 110 in step SA1 of FIG. In the control unit 100, the contact member 81 is pressed against the object to be fastened, the contact switch unit 84 is pushed by the contact arm 82, the contact switch unit 84 is turned on at step SA2, the trigger 9 is operated, and the control unit 100 is turned on at step SA3. When the trigger switch section 90 is turned on, the bit rotating motor 40 of the first driving section 4 is driven at step SA4, and the bit moving motor 50 of the second driving section 5 is driven at step SA5.

When the bit moving motor 50 is driven and rotates in one direction, the pulley 52 rotates in the forward direction, so that the wire 54 is wound around the pulley 52 . As 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 in 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 compresses the biasing member 33 together with the second moving member 32c. while moving forward along the axial direction.

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

As a result, the driver bit 2 held by the holding member 30 moves forward as indicated by the arrow A1, engages with the screw 200 supplied to the ejection port 81a of the nose portion 8, and moves the screw 200 forward. , pressed against the object to be fastened.

Further, when the bit rotation motor 40 is driven to rotate in the forward direction, which is one direction, the rotation guide member 31 rotates in the forward direction. When the rotation guide member 31 rotates in the positive direction, the connecting member 30 b connected to the holding member 30 is pressed against the groove 31 a of the rotation guide member 31 , so that 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 positive direction (clockwise) and screws it into the object to be fastened. The control unit 100 rotates the driver bit 2 by the first driving unit 4 to drive the screw into the object to be fastened. The driver bit 2 is moved forward by the second driving unit 5 based on the load applied to the motor 50, the rotation speed of the bit moving motor 50, etc., so that the driver bit 2 follows the screw screwed into the object to be fastened. .

At step SA6, the control unit 100 sets the amount of rotation of the bit moving motor 50 to the set value selected by the setting unit 110, and as shown in FIGS. When it is determined that P2 has been reached, the driving of the bit rotating motor 40 is stopped at step SA7, and after stopping forward rotation of the bit moving motor 50 at step SA8, the bit moving motor 50 is reversed at step SA9. .

When the bit movement motor 50 rotates in the opposite direction, the wire 54 is pulled out of the pulley 52 by rotating the pulley 52 in the opposite direction. When the wire 54 is pulled out from the pulley 52, the second moving member 32c moves forward, thereby extending the compressed biasing member 33 and pushing 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 axially moves rearward along with the second moving member 32c. Moving.

When the first moving member 32a moves backward, the holding member 30, which is connected to the first moving member 32a by the connecting member 30b, is guided by the groove 31a of the rotation guide member 31 and the driver bit. 2 in the backward direction along the axial direction.

At step SA10, the control unit 100 rotates the bit moving motor 50 in reverse to the initial position where the wire 54 is pulled out from the pulley 52 by a predetermined amount, and moves the holding member 30 and the moving member until the tip of the driver bit 2 returns to the standby position P1. 32 moves backward, the reverse rotation of the bit moving motor 50 is stopped in step SA11.

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. Direct contact with the rear frame 10c is suppressed, and noise generation and damage can be suppressed. When the trigger switch section 90 is turned off, the control section 100 rotates the screw feed motor 70 in one direction, thereby lowering the engaging section 73 . When the engaging portion 73 descends to the position where it engages with the next screw 200 , the control portion 100 reverses the screw feed motor 70 to raise the engaging portion 73 and move the next screw 200 into the injection passage 80 . supply.

15A to 15C are cross-sectional views showing the fastening state of the screw. FIG. 15A is a so-called flush state in which the head 201 of the screw 200 is neither raised nor embedded in the surface of the fastening target 202, and FIG. 15C shows a state in which the head 201 of the screw 200 is floating from the object 202 to be fastened, and FIG.

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 countersunk screw, the surface of the head portion 201 of the screw 200 is aligned with the fastening object 202 as shown in FIG. 15A. It is preferable that the advance amount of the driver bit 2 is set so as to be in a so-called flush state that is the same as the surface of the driver bit 2 . Note that the screw 200 is not limited to a countersunk screw, and if it is a pan head screw, a bind screw, a truss screw, or the like, the bearing surface of the head 201 of the screw 200 is in contact with the surface of the object 202 to be fastened, and the head 201 of the screw 200 is fastened. It is preferable that the advance amount of the driver bit 2 is set so as not to be in a state of floating from the object 202 .

When the tip of the driver bit 2 reaches the operation end position P2, if the head 201 of the screw 200 is in a state of floating from the fastening object 202 as shown in FIG. ) is set by the setting unit 110, and the number of rotations (the amount of rotation) of the bit moving motor 50 is increased, thereby increasing the advance amount of the driver bit 2 and advancing the operation end position P2. On the other hand, when the head 201 of the screw 200 is buried in the fastening object 202 as shown in FIG. By decreasing the number of revolutions (amount of rotation) of the screwdriver bit 2, the amount of advance of the driver bit 2 is decreased, and the operation end position P2 is retracted.

As described above, the amount of movement (amount of advance) of the driver bit 2 is defined by the number of rotations (amount of rotation) of the bit movement motor 50 . Then, after rotating the bit moving motor 50 by the amount of rotation set by the setting unit 110 starting from the standby position P1, which is the initial position of the driver bit 2, the bit moving motor 50 stops rotating or rotates in reverse. An end-of-operation position P2 is controlled. Therefore, the tightening depth can be adjusted.

In this manner, the tip position of the driver bit 2 held by the holding member 30 can be advanced by a predetermined amount based on the amount of rotation of the bit moving motor 50 with reference to the predetermined standby position P1. A holding member 30 to be attached and a standby position of a moving member 32 for moving the holding member 30 are set. The operation of setting the standby positions of the holding member 30 and the moving member 32 is called a first initialization operation.

Then, the holding member 30 and the moving member 32 are moved to a set standby position before starting the driving and fastening operations, and the positions of the holding member 30 and the moving member 32 are controlled by the amount of rotation of the bit moving motor 50 with reference to the standby position. do. Then, the holding member 30 and the moving member 32 are moved forward from the set standby position to a predetermined moving amount (advance amount) to perform the fastening operation. The operation of moving the holding member 30 and the moving member 32 to the standby positions set in the first initialization operation is called a second initialization operation.

As means for setting the standby positions of the holding member 30 and the moving member 32 in the first initialization operation, a sensor is used, and the maximum position of the range in which the holding member 30 and the moving member 32 can move back and forth is used as a reference. Conceivable. When a sensor is used, the detection position of the sensor or a position moved from the detection position by a specified amount is set as the standby position.

Further, when the maximum position of the range of forward and backward movement is used, a position where the holding member 30 and the moving member 32 are moved by a specified amount from the front end position or the rear end position is set as the standby position.

16A to 16D are explanatory diagrams showing an example of the operation of setting the standby positions of the holding member and the moving member in the first initialization operation. Next, the standby positions of the holding member 30 and the moving member 32 are set. Operation will be explained. 16A to 16D show an example of the operation of setting the standby position using the maximum position of the range in which the holding member 30 and the moving member 32 can move back and forth.

As shown in FIG. 16A, the control unit 100 rotates the bit moving motor 50 in one positive direction from a state where the holding member 30 and the moving member 32 are at arbitrary positions. When the bit moving motor 50 rotates forward, the wire 54 is wound around the pulley 52 , so that the moving member 32 and the holding member 30 connected to the moving member 32 move along the rotation guide member 31 toward the axis of the driver bit 2 . Move forward along the direction.

As shown in FIG. 16B, when the bit moving motor 50 rotates forward until the holding member 30 and the moving member 32 move to the front end position PF, which is one end position, the control unit 100 rotates the bit moving motor 50 forward. The rotation is stopped, and the holding member 30 and the moving member 32 are moved to the front end position PF.

Next, the control unit 100 rotates the bit moving motor 50 in the opposite direction. When the bit moving motor 50 reverses, 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 are Along the rotation guide member 31 , the screwdriver bit 2 moves rearward along the axial direction.

As shown in FIG. 16C, when the bit moving motor 50 is reversed until the holding member 30 and the moving member 32 move to the rear end position PE, which is the other end position, the control unit 100 rotates the bit moving motor 50 in the reverse direction. is stopped, and the holding member 30 and the moving member 32 are moved to the rear end position PE by the biasing of the biasing member 33 .

The control unit 100 acquires the amount of movement of the holding member 30 and the moving member 32 from the front end position PF to the rear end position PE as the overall distance L1. The amount of movement from the front end position PF to the rear end position PE is obtained from the amount of rotation of the bit movement motor 50 .

The controller 100 presets the amount of movement from the standby position of the holding member 30 and the moving member 32 to the front end position PF as the target amount of movement L2. The control unit 100 sets the difference between the total distance L1 from the front end position PF to the rear end position PE and the preset target movement amount L2 as the standby position movement amount L3, and stores it. The standby position movement amount L3 is the amount of movement of the holding member 30 and the moving member 32 from the rear end position PE.

As shown in FIG. 16D, the control unit 100 rotates the bit moving motor 50 forward to move the holding member 30 and the moving member 32 forward from the rear end position PE. When the control unit 100 rotates the bit moving motor 50 forward at a number of revolutions (amount of rotation) corresponding to the standby position moving amount L3, the forward rotation of the bit moving motor 50 is stopped, and the holding member 30 and the moving member 32 are put on standby. position, and the tip of the driver bit 2 held by the holding member 30 is moved to the standby position P1.

In addition, when moving the holding member 30 and the moving member 32 to the front end position PF and the rear end position PE, when the second moving member 32c hits the buffer member 32d, etc., the durability of the tool is not affected. It is desirable to drive at a low speed of

17A to 17C are explanatory diagrams showing an example of the operation of moving the holding member and the moving member to the standby position in the second initialization operation. The operation of moving to a position will be described.

As shown in FIG. 17A, the control unit 100 rotates the bit moving motor 50 in the opposite direction from the state where the holding member 30 and the moving member 32 are at arbitrary positions. When the bit moving motor 50 reverses, 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 are Along the rotation guide member 31 , the screwdriver bit 2 moves rearward along the axial direction.

As shown in FIG. 17B , when the bit moving motor 50 is reversed until the holding member 30 and the moving member 32 move to the rear end position PE, the control unit 100 stops the reverse rotation of the bit moving motor 50 and pushes the biasing member 33 forward. , the holding member 30 and the moving member 32 are moved to the rear end position PE.

As shown in FIG. 17C, the control unit 100 rotates the bit moving motor 50 forward to move the holding member 30 and the moving member 32 forward from the rear end position PE. When the control unit 100 rotates the bit moving motor 50 forward at a number of revolutions (amount of rotation) corresponding to the standby position moving amount L3, the forward rotation of the bit moving motor 50 is stopped, and the holding member 30 and the moving member 32 are put on standby. position, and the tip of the driver bit 2 held by the holding member 30 is moved to the standby position P1.

In the first initialization operation described with reference to FIGS. 16A to 16D, the operation of setting the standby positions of the holding member 30 and the moving member 32 is performed at the factory when the product is shipped, for example, regardless of the user's operation. Thus, the standby position movement amount L3 is stored in advance.

On the other hand, in the second initialization operation described with reference to FIGS. 17A to 17C, the operation of moving the holding member 30 and the moving member 32 to the standby position based on the standby position movement amount L3 enables stable fastening operation. Therefore, it is preferable to perform the adjustment each time the fastening tool 1 is powered on.

Therefore, a first initialization operation and a second initialization operation, which are initialization operations related to the standby positions of the holding member 30 and the moving member 32, are configured to be selectable.

FIG. 18 is a flow chart showing an example of the operation of selecting the first initialization operation and the second initialization operation.

When power is turned on in step SB1 of FIG. 18, the control unit 100 selects an initialization operation to be executed in step SB2. When the control unit 100 selects execution of the first initialization operation, at step SB3, the first initialization operation described above with reference to FIGS. Set the standby position. When the control unit 100 selects execution of the second initialization operation, the control unit 100 executes the second initialization operation described above with reference to FIGS. It is moved to the standby position based on the standby position movement amount L3. After executing the second initialization operation, the control unit 100 executes a normal fastening operation in step SB5 according to the above-described flowchart of FIG. 14 and the like.

As described above, in the first initialization operation, the holding member 30 and the moving member 32 are moved at a low speed from the front end position PF to the rear end position PE, and the entire distance L1 from the front end position PF to the rear end position PE is A substrate (not shown) constituting the control unit 100 is set as a standby position movement amount L3 by obtaining a movement amount from the rear end position PE determined so that the movement amount from the front end position PF is equal to a predetermined target movement amount L2. Record in memory above. As a result, the standby positions of the holding member 30 and the moving member 32 can be set at a fixed position from the front end position PF, for example, by eliminating various machine variations such as dimensional differences within tolerances.

In the second initialization operation, the holding member 30 and the moving member 32 are moved from the rear end position PE to the standby position according to the standby position movement amount L3 each time the power is turned on for use by the user. , the amount of movement of the holding member 30 and the moving member 32 can be minimized. Furthermore, in the second initialization operation, the tip of the driver bit 2 is positioned at the standby position P1 behind the injection passage 80, and the screw 200 is supplied to the injection passage 80, and the second initialization operation is performed. can run.

As described above, the movement amount (advance amount) of the driver bit 2 is determined by starting from the standby position of the holding member 30 and the moving member 32, that is, the standby position P1 of the driver bit 2, and the number of rotations of the bit moving motor 50. amount). Therefore, if the standby positions of the holding member 30 and the moving member 32, ie, the standby position P1 of the driver bit 2, vary, the tightening depth set by the setting unit 110 varies.

On the other hand, by performing the second initialization operation each time the power is turned on, the setting unit 110 sets the standby position of the holding member 30 and the moving member 32, that is, the standby position P1 of the driver bit 2 as a starting point. By rotating the bit moving motor 50 by the amount of rotation, the tightening depth of the screw can be adjusted accurately.

FIG. 19 is a flowchart showing a modification of the operation of the fastening tool of the present embodiment, and FIG. 20 is a graph showing the relationship between the output of the contact switch section and the control of the bit rotation motor and the bit movement motor. Another example of the fastening operation of the fastening tool of the present embodiment will be described with reference to each drawing. In this modification, the presence or absence of floating of the fastening tool 1 with respect to the fastening object is detected from the output of the contact switch section 84, and the bit rotating motor 40 and the bit moving motor 50 are controlled.

In the stand-by state of the fastening tool 1, as shown in FIG. 1A, the tip of the driver bit 2 is positioned at the stand-by position P1 behind the injection passage 80, and the screw 200 can be supplied to the injection passage 80.

19, the control unit 100 sets the amount of rotation of the bit moving motor 50 that defines the advance amount of the driver bit 2, based on the set value selected by the setting unit 110. FIG. In the control unit 100, the contact member 81 is pressed against the object to be fastened, the contact switch unit 84 is pushed by the contact arm 82, the contact switch unit 84 is turned on at step SC2, the trigger 9 is operated, and the control unit 100 is turned on at step SC3. When the trigger switch section 90 is turned on, the bit rotating motor 40 of the first driving section 4 is driven at step SC4, and the bit moving motor 50 of the second driving section 5 is driven at step SC5.

When the bit moving motor 50 is driven and rotates in one direction, the pulley 52 rotates in the forward direction, so that the wire 54 is wound around the pulley 52, and the second moving member 32c is connected to the wire 54. The moving member 32 and the holding member 30 connected to the moving member 32 by the first moving member 32a move forward.

As a result, the driver bit 2 held by the holding member 30 moves forward as indicated by the arrow A1, engages with the screw 200 supplied to the ejection port 80 of the nose portion 8, and moves the screw 200 forward. , pressed against the object to be fastened.

Further, when the bit rotation motor 40 is driven to rotate in one direction, that is, 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 positive direction (clockwise) and screws it into the object to be fastened. The control unit 100 rotates the driver bit 2 by the first driving unit 4 to drive the screw into the object to be fastened. The driver bit 2 is moved forward by the second driving unit 5 based on the load applied to the motor 50, the rotation speed of the bit moving motor 50, etc., so that the driver bit 2 follows the screw screwed into the object to be fastened. .

When the control unit 100 determines in step SC6 that the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and that the tip of the driver bit 2 has reached the set operation end position P2, step SC7. , the driving of the bit moving motor 50 is stopped.

After stopping the driving of the bit moving motor 50 at step SC7, the control section 100 determines whether the contact switch section 84 is on at step SC8. If the contact switch unit 84 is on, the control unit 100 determines that the fastening tool 1 is not floating in the direction away from the fastening object. The rotation is stopped, and the bit moving motor 50 is reversed at step SC10.

When the bit moving motor 50 rotates in the opposite direction, the pulley 52 rotates in the opposite direction, the wire 54 is pulled out from the pulley 52, and the second moving member 32c is pushed by the biasing member 33 to move. The holding member 30 connected to the member 32 and the moving member 32 by the first moving member 32a moves backward.

In step SC11, the control unit 100 rotates the bit moving motor 50 in reverse to the initial position where the wire 54 is pulled out from the pulley 52 by a predetermined amount, and rotates the holding member 30 and the moving member until the tip of the driver bit 2 returns to the standby position P1. 32 moves backward, the reverse rotation of the bit moving motor 50 is stopped in step SC12.

In step SC8, if the contact switch unit 84 is off, the control unit 100 determines that the fastening tool 1 is floating in the direction away from the object to be fastened. The drive to rotate the rotary motor 40 in the forward direction is continued.

As a result, the driver bit 2 held by the holding member 30 rotates the screw 200 in the forward direction, further screwing the screw 200 into the object to be fastened, and the fastening tool 1 moves closer to the object to be fastened. Therefore, the fastening tool 1 moves relative to the contact arm 82, and the contact switch portion 84 is pushed by the contact arm 82 to turn on the contact switch portion 84. As shown in FIG. When the contact switch unit 84 is on, the control unit 100 executes the above-described steps SC9 to SC12 in order to end the fastening operation, stops the bit rotating motor 40, rotates the bit moving motor 50 in reverse, and rotates the driver bit. 2 to return to the standby position.

Further, the control unit 100 prevents the bit moving motor 50 from rotating due to an external force during the operation of rotating the bit rotating motor 40 in the forward direction in a state where the contact switch unit 84 is turned off and the driving of the bit moving motor 50 is stopped. By performing such control called braking operation, the holding member 30, the moving member 32, and the driver bit 2 held by the holding member 30 are maintained in a stopped state at the operation end position P2.

However, while driving the bit moving motor 50 is stopped and the bit rotating motor 40 is rotated in the forward direction, the fastening tool 1 is pressed against the object to be fastened by the operator. 200 will be tightened. Therefore, even if the bit moving motor 50 is braked, the holding member 30, the moving member 32, and the driver bit 2 held by the holding member 30 are moved to the operation end position P2 by the force applied by the operator. may move backwards from

Therefore, in step SC13, the control unit 100 detects whether or not the bit moving motor 50 is reversely rotated. When detecting the reverse rotation of the bit moving motor 50, the control unit 100 returns to step SC5, rotates the bit moving motor 50 forward, and rotates the holding member. 30 and the moving member 32 are moved forward to return the driver bit 2 to the operation end position P2. Then, the forward rotation of the bit moving motor 50 is stopped and a braking operation is performed.

In order for the contact switch portion 84 to switch between on and off by the contact arm 82, the contact arm 82 needs to move by a predetermined amount. Therefore, as described above, in step SC8, it is detected that the contact switch section 84 is turned off, and while the driving of the bit moving motor 50 is stopped, the bit rotating motor 40 continues to rotate in the forward direction. As a result, the positions of the holding member 30 and the moving member 32 may fluctuate while the contact arm 82 moves until the contact switch portion 84 is switched from off to on. Therefore, it is desirable to provide a detection section for detecting the position of the contact arm 82 . It should be noted that the rotation of the bit holding portion 3 and the axial movement of the bit holding portion 3 may be performed by a single motor. The timing to stop driving the single motor described above may be controlled.

FIG. 21 is a flow chart showing another modification of the operation of the fastening tool according to this embodiment, and FIG.
22A and 22B are graphs showing the relationship between the load and the control of the bit rotating motor. Next, another modified example of the fastening operation of the fastening tool of the present embodiment will be described with reference to these figures. In this modification, the bit rotating motor 40 is controlled by detecting the load applied to the bit rotating motor 40 .

In the stand-by state of the fastening tool 1, as shown in FIG. 1A, the tip of the driver bit 2 is positioned at the stand-by position P1 behind the injection passage 80, and the screw 200 can be supplied to the injection passage 80.

21, the control unit 100 sets the amount of rotation of the bit moving motor 50 that defines the advance amount of the driver bit 2, based on the setting value selected by the setting unit 110. FIG. In the control unit 100, the contact member 81 is pressed against the object to be fastened, the contact switch unit 84 is pushed by the contact arm 82, the contact switch unit 84 is turned on at step SD2, the trigger 9 is operated, and the control unit 100 is operated at step SD3. When the trigger switch section 90 is turned on, the bit rotating motor 40 of the first driving section 4 is driven in step SD4, and the bit moving motor 50 of the second driving section 5 is driven in step SD5.

When the bit moving motor 50 is driven and rotates in one direction, the pulley 52 rotates in the forward direction, so that the wire 54 is wound around the pulley 52, and the second moving member 32c is connected to the wire 54. The moving member 32 and the holding member 30 connected to the moving member 32 by the first moving member 32a move forward.

As a result, the driver bit 2 held by the holding member 30 moves forward as indicated by the arrow A1, engages with the screw 200 supplied to the ejection port 80 of the nose portion 8, and moves the screw 200 forward. , pressed against the object to be fastened.

Further, when the bit rotation motor 40 is driven to rotate in one direction, that is, 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 positive direction (clockwise) and screws it into the object to be fastened. The control unit 100 rotates the driver bit 2 by the first driving unit 4 to drive the screw into the object to be fastened. The driver bit 2 is moved forward by the second driving unit 5 based on the load applied to the motor 50, the rotation speed of the bit moving motor 50, etc., so that the driver bit 2 follows the screw screwed into the object to be fastened. .

At step SD6, the control unit 100 determines whether the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and the tip of the driver bit 2 has reached the set operation end position P2. When the control unit 100 determines that the amount of rotation of the bit moving motor 50 has not reached the set value selected by the setting unit 110, in step SD7, the load applied to the bit rotating motor 40 is detected, and the predetermined load is detected. is detected, the bit rotation motor 40 is controlled in step SD8.

The rotational speed of the driver bit 2 varies depending on the magnitude of the load applied to the bit rotating motor 40. If the current and voltage applied to the bit rotating motor 40 are the same, the higher the load applied to the bit rotating motor 40, the higher the load. , the rotation speed decreases. Therefore, the control unit 100 detects the load applied to the bit rotating motor 40 as a variation detecting unit that detects factors that cause the rotation speed of the bit rotating motor 40 to vary. The output of the bit rotating motor 40 is reduced by, for example, decreasing the voltage applied to the bit rotating motor 40 and decreasing the current flowing through the bit rotating motor 40 compared to the case where the bit rotating motor 40 is high.

As a result, when the load applied to the bit rotating motor 40 is low, the rotational speed of the bit rotating motor 40 is reduced. It is possible to suppress the difference in the rotation speed of the bit rotation motor 40 depending on the magnitude of the load applied to the bit rotation motor 40 . Therefore, variations in the fastening speed of the screw 200 are suppressed.

When the control section 100 determines in step SD6 that the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting section 110 and that the tip of the driver bit 2 has reached the set operation end position P2, step SD9. The driving of the bit rotating motor 40 is stopped at step SD10, and after stopping the forward rotation of the bit moving motor 50 at step SD10, the bit moving motor 50 is reversed at step SD11.

When the bit moving motor 50 rotates in the opposite direction, the pulley 52 rotates in the opposite direction, the wire 54 is pulled out from the pulley 52, and the second moving member 32c is pushed by the biasing member 33 to move. The holding member 30 connected to the member 32 and the moving member 32 by the first moving member 32a moves backward.

At step SD12, the control unit 100 rotates the bit moving motor 50 in reverse to the initial position where the wire 54 is pulled out from the pulley 52 by a predetermined amount, and moves the holding member 30 and the moving member until the tip of the driver bit 2 returns to the standby position P1. 32 moves backward, the reverse rotation of the bit moving motor 50 is stopped in step SD13.

In the control for reducing the output of the bit rotating motor 40, as shown in FIG. 22A, after a predetermined load is detected, the amount of rotation for the driver bit 2 to move to the operation end position until the bit rotating motor 40 rotates is constant. The output may be reduced so as to increase the speed. Further, as shown in FIG. 22B, after a predetermined load is detected, the amount of rotation for moving the driver bit 2 to the operation end position and the rotation of the bit rotation motor 40 are gradually increased so that the target rotation speed is reached. Output may be reduced.

Note that fluctuations in the power supply voltage cause a difference in the rotational speed of the driver bit 2, and the lower the power supply voltage, the lower the rotational speed. Therefore, the control unit 100 detects the power supply voltage as a variation detection unit that detects factors that cause the rotation speed of the bit rotation motor 40 to vary. 40 power down.

As a result, when the power supply voltage is high, the rotation speed of the bit rotation motor 40 is reduced compared to when the power supply voltage is low, so that variations in the power supply voltage can cause a difference in the rotation speed of the bit rotation motor 40. Suppressed. Therefore, variations in the fastening speed of the screw 200 are suppressed.

In addition, the control unit 100 detects the rotation speed of the bit rotation motor 40 while the target rotation speed of the bit rotation motor 40 is set. 40 may be compared and the bit rotation motor 40 may be controlled so as to achieve the target rotation speed.

Now, if the rotation speed of the bit rotating motor 40 is reduced, it becomes a factor of lowering the work speed of fastening the screw to the fastening object. On the other hand, during the stopping process of the bit rotating motor 40 after the screw has been tightened to the target screw tightening depth set by the setting unit 110, the driver bit 2 does not stop until the rotation of the bit rotating motor 40 completely stops. rotates to tighten the screw into the object to be fastened. Therefore, the faster the rotation speed of the bit rotating motor 40 immediately before the rotation stops, the more the screw is tightened than the target.

Thus, the reason why the quality of the screw tightening operation is degraded due to the difference in the rotational speed of the bit rotating motor 40 is the rotational speed of the bit rotating motor 40 immediately before it stops rotating. Therefore, immediately before the moving amount (advance amount) of the holding member 30 and the moving member 32 reaches the target screw tightening depth set by the setting unit 110, the rotation speed of the bit rotating motor 40 is affected by the load. The desired effect can be obtained if it is constant by excluding

The load applied to the bit rotation motor 40 increases when tightening of the screw to the object to be fastened starts, but the load varies depending on the material of the object to be fastened. Therefore, after the load is detected for controlling the rotational speed of the bit rotating motor 40, until the target screw tightening depth is reached, the bit rotating motor 40 described above based on the load, the power supply voltage, etc. Execute rotation speed control.

In addition, the control unit 100 is provided with a timer, and controls the rotation speed of the bit rotation motor 40 based on the load, the power supply voltage, etc. after a predetermined time has elapsed since the bit rotation motor 40 started to be driven (forward rotation). control may be performed. Further, a position detection unit for detecting the positions of the holding member 30 and the moving member 32 is provided, and after the positions of the holding member 30 and the moving member 32 reach predetermined positions, the above-described bit rotation motor based on the load, power supply voltage, etc. 40 rotation speed control may be performed. The predetermined positions of the holding member 30 and the moving member 32 for controlling the rotation speed of the bit rotation motor 40 are set as targets from the position where the above-described load for controlling the rotation speed of the bit rotation motor 40 is detected. It is set up to the position where the screw tightening depth is reached.

In addition, in the method of setting the target rotation speed of the bit rotation motor 40 and controlling the output, the rotation speed of the bit rotation motor 40 may decrease to the target rotation speed due to the influence of the length of the control execution section. Before that, it is conceivable that the target screw tightening depth is reached. Therefore, the braking control of the bit rotating motor 40 may be performed during the control for reducing the rotating speed of the bit rotating motor 40 to the target rotating speed. For example, when the deviation between the target rotation speed of the bit rotation motor 40 and the detected actual rotation speed is large, the bit rotation motor 40 is braked until the deviation between the actual rotation speed and the target rotation speed is within a specified range. Control may be performed to reduce the rotation speed of the bit rotation motor 40 to the target rotation speed when the deviation falls within a specified range.

Furthermore, if the driver bit 2 is disengaged from the screw after reaching the target screw tightening depth, the screw will not be further tightened even if the driver bit 2 rotates. After the driver bit 2 advances until it reaches the target screw tightening depth, the bit moving motor 50 may be reversed before the bit rotating motor 40 stops rotating. A single motor may be used for the rotation of the bit holding part 3 and the movement of the bit holding part 3 in the axial direction. The motor may be controlled by detecting the factor of speed fluctuation.

FIG. 23 is a flowchart showing another modification of the operation of the fastening tool of the present embodiment, FIG. 24A is a graph showing the relationship between the rotational speeds of the bit rotating motor and the bit moving motor under feedback (FB) control, and FIG. 24B. is a graph showing the relationship between the screw moving speed due to the rotation of the bit rotating motor under feedback (FB) control and the moving speed of the driver bit due to the bit moving motor. Another modified example of the fastening operation of the fastening tool will be described. In this modification, the moving speed of the screw by the rotation of the bit rotating motor 40 and the moving speed of the driver bit by the bit moving motor 50 are synchronized by feedback control.

In the stand-by state of the fastening tool 1, as shown in FIG. 1A, the tip of the driver bit 2 is positioned at the stand-by position P1 behind the injection passage 80, and the screw 200 can be supplied to the injection passage 80.

23, the control unit 100 sets the amount of rotation of the bit moving motor 50 that defines the advance amount of the driver bit 2, based on the setting value selected by the setting unit 110. FIG. In the control unit 100, the contact member 81 is pressed against the object to be fastened, the contact switch unit 84 is pressed by the contact arm 82, the contact switch unit 84 is turned on in step SE2, the trigger 9 is operated, and the trigger 9 is operated in step SE3. When the trigger switch section 90 is turned on, the bit rotating motor 40 of the first driving section 4 is driven at step SE4, and the bit moving motor 50 of the second driving section 5 is driven at step SE5.

When the bit moving motor 50 is driven and rotates in one direction, the pulley 52 rotates in the forward direction, so that the wire 54 is wound around the pulley 52, and the second moving member 32c is connected to the wire 54. The moving member 32 and the holding member 30 connected to the moving member 32 by the first moving member 32a move forward.

As a result, the driver bit 2 held by the holding member 30 moves forward as indicated by the arrow A1, engages with the screw 200 supplied to the ejection port 80 of the nose portion 8, and moves the screw 200 forward. , pressed against the object to be fastened.

Further, when the bit rotation motor 40 is driven to rotate in one direction, that is, 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 positive direction (clockwise) and screws it into the object to be fastened. The control unit 100 causes the second driving unit 5 to move the driver bit 2 forward in conjunction with the operation of rotating the driver bit 2 by the first driving unit 4 to screw the screw into the object to be fastened. , the driver bit 2 follows the screw screwed into the object to be fastened.

At step SE6, the control unit 100 determines whether the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and the tip of the driver bit 2 has reached the set operation end position P2. When the control unit 100 determines that the amount of rotation of the bit moving motor 50 has not reached the set value selected by the setting unit 110, the load applied to the bit moving motor 50 is detected in step SE7, and the predetermined load is detected. is detected, the number of rotations of the bit rotation motor 40 and the number of rotations of the bit movement motor 50 are obtained in step SE8.

In step SE9, the control unit 100 controls the movement speed when the screw 200 moves forward when the screw 200 is fastened to the object to be fastened by the rotation of the bit rotation motor 40 and the rotation of the bit movement motor 50. The rotational speed of the bit rotation motor 40 and the bit rotation speed are adjusted so that the moving speeds of the holding member 30 and the moving member 32 moving forward and the moving speed of the driver bit 2 attached to the holding member 30 substantially match as shown in FIG. 24B. The rotational speeds of the bit rotating motor 40 and the bit moving motor 50 are obtained based on the rotational speed of the moving motor 50, the gear ratio of the speed reducer, and the like.

In step SE10, the control section 100 controls the bit moving motor 50 by feedback control based on the number of rotations of the bit rotating motor 40, the number of rotating bits of the bit moving motor 50, the gear ratio of the speed reducer, and the like. For example, the control is performed by increasing or decreasing the PWM output to the bit moving motor 50 to adjust the rotation speed.

When the control unit 100 determines in step SE6 that the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and that the tip of the driver bit 2 has reached the set operation end position P2, step SE11. The driving of the bit rotating motor 40 is stopped at step SE12, and after the forward rotation of the bit moving motor 50 is stopped at step SE12, the bit moving motor 50 is reversed at step SE13.

When the bit moving motor 50 rotates in the opposite direction, the pulley 52 rotates in the opposite direction, the wire 54 is pulled out from the pulley 52, and the second moving member 32c is pushed by the biasing member 33 to move. The holding member 30 connected to the member 32 and the moving member 32 by the first moving member 32a moves backward.

In step SE14, the control unit 100 rotates the bit moving motor 50 in reverse to the initial position where the wire 54 is pulled out from the pulley 52 by a predetermined amount, and rotates the holding member 30 and the moving member until the tip of the driver bit 2 returns to the standby position P1. 32 moves backward, the reverse rotation of the bit moving motor 50 is stopped in step SE15.

Note that the above-described feedback control is necessary after the screw 200 comes into contact with the object to be fastened and the load on the bit rotating motor 40 and the bit moving motor 50 changes. Therefore, the control when the feedback control is not executed is set to the first control mode, and the control when the feedback control is executed is set to the second control mode. The first control mode is executed before detecting the load of . Then, when a predetermined load is detected in either or both of the bit rotating motor 40 and the bit moving motor 50, the first control mode is switched to the second control mode, and the second control mode is executed. As a result, it is possible to suppress a delay in working time.

Further, as means for improving the responsiveness of the feedback control and realizing more stable work quality, the acceleration/deceleration limit value for the bit moving motor 50 is set to It can be changed at non-execution time. Normally, when PWM output is performed to the motor, control is executed to prevent the acceleration current from becoming excessive, especially during startup, by limiting the amount of acceleration per unit time in order to stabilize the output of the motor. However, if the above-described feedback control is executed while limiting the acceleration of the bit moving motor 50 at startup, the PWM output generated by the feedback control is limited and applied to the bit moving motor 50. Therefore, the response to the feedback control is sexuality worsens. Therefore, during execution of feedback control, it is desirable to set the acceleration limit amount to be larger than when the motor is started when feedback control is not executed.

FIG. 25 is a flow chart showing another modification of the operation of the fastening tool of this embodiment, and FIGS. 26A and 26B are graphs showing the relationship between the load and the control of the bit moving motor. Another modified example of the fastening operation of the fastening tool of the present embodiment will be described with reference to FIG. In this modification, the bit moving motor 50 is controlled by detecting the load on the bit moving motor 50 .

In the stand-by state of the fastening tool 1, as shown in FIG. 1A, the tip of the driver bit 2 is positioned at the stand-by position P1 behind the injection passage 80, and the screw 200 can be supplied to the injection passage 80.

25, the control unit 100 sets the amount of rotation of the bit moving motor 50 that defines the advance amount of the driver bit 2, based on the set value selected by the setting unit 110. FIG. In the control unit 100, the contact member 81 is pressed against the object to be fastened, the contact switch unit 84 is pushed by the contact arm 82, the contact switch unit 84 is turned on in step SF2, the trigger 9 is operated, and the control unit 100 is turned on in step SF3. When the trigger switch section 90 is turned on, the bit rotating motor 40 of the first driving section 4 is driven in step SF4, and the bit moving motor 50 of the second driving section 5 is driven in step SF5.

When the bit moving motor 50 is driven and rotates in one direction, the pulley 52 rotates in the forward direction, so that the wire 54 is wound around the pulley 52, and the second moving member 32c is connected to the wire 54. The moving member 32 and the holding member 30 connected to the moving member 32 by the first moving member 32a move forward.

As a result, the driver bit 2 held by the holding member 30 moves forward as indicated by the arrow A1, engages with the screw 200 supplied to the ejection port 80 of the nose portion 8, and moves the screw 200 forward. , pressed against the object to be fastened.

Further, when the bit rotation motor 40 is driven to rotate in one direction, that is, 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 positive direction (clockwise) and screws it into the object to be fastened. The control unit 100 causes the second driving unit 5 to move the driver bit 2 forward in conjunction with the operation of rotating the driver bit 2 by the first driving unit 4 to screw the screw into the object to be fastened. , the driver bit 2 follows the screw screwed into the object to be fastened.

In step SF6, the control unit 100 determines whether the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and the tip of the driver bit 2 has reached the set operation end position P2. When the control unit 100 determines that the amount of rotation of the bit moving motor 50 has not reached the set value selected by the setting unit 110, in step SF7, the load applied to the bit moving motor 50 is detected, and the predetermined load is detected. is detected, the bit moving motor 50 is controlled in step SF8.

In order to suppress the occurrence of excessive impact when the screw 200 is pressed against the object to be fastened by moving the holding member 30 and the moving member 32 forward by driving the bit moving motor 50, the fastening speed must be reduced. In order to prevent this, the bit rotating motor 40 is operated at the maximum output within the expected range, and the voltage applied to the bit moving motor 50 is lowered, the current applied to the bit moving motor 50 is lowered, and so on. limit the output of

If the ratio of the advance amount of the screw per one rotation of the bit rotation motor 40 to the advance amount of the driver bit 2 per one rotation of the bit movement motor 50 becomes low, the advance amount of the driver bit 2 by the bit movement motor 50 is Cam-out occurs because the amount of advance of the screw by the rotary motor 40 cannot be caught up. On the other hand, when the ratio of the advance amount of the screw per one rotation of the bit rotating motor 40 to the advance amount of the driver bit 2 per one rotation of the bit moving motor 50 increases, the advance amount of the driver bit 2 by the bit moving motor 50 increases. , the amount of advance of the screw by the bit rotation motor 40 is greatly exceeded, so that an excessive force is required for pressing the fastening tool 1 toward the fastening object by the operator.

Therefore, as a target value for the output limit, the ratio of the advance amount of the driver bit 2 per one rotation of the bit moving motor 50 to the advance amount of the screw per one rotation of the bit rotating motor 40 is 0.8 to 5 times. It is preferable to set it to a degree. As a result, the occurrence of cam-out is suppressed, and an excessive force is not required to press the fastening tool 1 in the direction of the fastening object by the operator. It is possible to suppress the occurrence of impact.

In addition, when the load of the bit moving motor 50 generated after the screw 200 comes into contact with the object to be fastened is detected, the output of the bit moving motor 50 is limited, so that when the screw 200 is pressed against the object to be fastened, the holding member 30 And by decelerating the moving member 32, a further impact suppression effect can be obtained.

In the control for limiting the output of the bit moving motor 50, as shown in FIG. 26A, after a predetermined load is detected, the amount of rotation of the driver bit 2 to move to the operation end position until the bit rotating motor 40 rotates. The output may be restricted so that the rotation speed of 50 is constant. Further, as shown in FIG. 26B, the bit moving motor 50 is rotated forward at the first rotation speed until a predetermined load is detected. After the predetermined load is detected, the bit moving motor 50 is rotated forward at a second rotation speed that is lower in order to reduce the impact when the screw 200 is pressed against the object to be fastened. Further, after the lapse of a predetermined buffering time for weakening the impact when the screw 200 is pressed against the object to be fastened, the driver bit 2 is rotated at a third rotation speed that is lower than the first rotation speed and higher than the second rotation speed. The output may be limited so that the rotational speed is constant until the bit rotation motor 40 rotates until it reaches the operation end position.

Note that fluctuations in the power supply voltage cause a difference in the moving speed (advance speed) of the holding member 30 and the moving member 32. The higher the power supply voltage, the faster the moving speed. , an excessive impact is more likely to occur. Therefore, the control unit 100 detects the power supply voltage, and lowers the output of the bit moving motor 50 as the power supply voltage is higher than when the power supply voltage is low.

This suppresses the occurrence of a difference in the rotational speed of the bit moving motor 50 due to fluctuations in the power supply voltage. Therefore, when the screw 200 is pressed against the object to be fastened, the occurrence of excessive impact is suppressed, and variation in the speed at which the screw 200 is pressed against the object to be fastened is suppressed.

When the control unit 100 determines in step SF6 that the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and that the tip of the driver bit 2 has reached the set operation end position P2, step SF9. The driving of the bit rotating motor 40 is stopped at step SF10, and after stopping the forward rotation of the bit moving motor 50 at step SF10, the bit moving motor 50 is reversed at step SF11.

When the bit moving motor 50 rotates in the opposite direction, the pulley 52 rotates in the opposite direction, the wire 54 is pulled out from the pulley 52, and the second moving member 32c is pushed by the biasing member 33 to move. The holding member 30 connected to the member 32 and the moving member 32 by the first moving member 32a moves backward.

In step SF12, the control unit 100 reverses the bit moving motor 50 to the initial position where the wire 54 is pulled out from the pulley 52 by a predetermined amount, and moves the holding member 30 and the moving member to the position where the tip of the driver bit 2 returns to the standby position P1. 32 moves backward, the reverse rotation of the bit moving motor 50 is stopped in step SF13.

FIG. 27 is a flowchart showing another modification of the operation of the fastening tool of this embodiment. Next, referring to each figure, another modification of the fastening operation of the fastening tool of this embodiment will be described. explain. In this modified example, the load applied to the bit moving motor 50 or the like is detected, and driving is suppressed when there is no screw.

In the stand-by state of the fastening tool 1, as shown in FIG. 1A, the tip of the driver bit 2 is positioned at the stand-by position P1 behind the injection passage 80, and the screw 200 can be supplied to the injection passage 80.

The control unit 100 sets the amount of rotation of the bit moving motor 50 that defines the advance amount of the driver bit 2 based on the setting value selected by the setting unit 110 in step SG1 of FIG. In the control unit 100, the contact member 81 is pressed against the object to be fastened, the contact switch unit 84 is pushed by the contact arm 82, the contact switch unit 84 is turned on in step SG2, the trigger 9 is operated, and the trigger 9 is operated in step SG3. When the trigger switch section 90 is turned on, the bit rotating motor 40 of the first driving section 4 is driven in step SG4, and the bit moving motor 50 of the second driving section 5 is driven in step SG5.

When the bit moving motor 50 is driven and rotates in one direction, the pulley 52 rotates in the forward direction, so that the wire 54 is wound around the pulley 52, and the second moving member 32c is connected to the wire 54. The moving member 32 and the holding member 30 connected to the moving member 32 by the first moving member 32a move forward.

As a result, the driver bit 2 held by the holding member 30 moves forward as indicated by the arrow A1, engages with the screw 200 supplied to the ejection port 80 of the nose portion 8, and moves the screw 200 forward. , pressed against the object to be fastened.

Further, when the bit rotation motor 40 is driven to rotate in one direction, that is, 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 positive direction (clockwise) and screws it into the object to be fastened. The control unit 100 causes the second driving unit 5 to move the driver bit 2 forward in conjunction with the operation of rotating the driver bit 2 by the first driving unit 4 to screw the screw into the object to be fastened. , the driver bit 2 follows the screw screwed into the object to be fastened.

At step SG6, the control unit 100 determines whether the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and the tip of the driver bit 2 has reached the set operation end position P2. If the control unit 100 determines that the amount of rotation of the bit moving motor 50 has not reached the set value selected by the setting unit 110, in step SG7, either the bit rotating motor 40 or the bit moving motor 50, or Detect the load on both. When a predetermined load is detected by pressing the screw 200 against the object to be fastened, the bit moving motor 50 rotates in the forward direction until the amount of rotation of the bit moving motor 50 reaches the set value selected by the setting unit 110. continue to rotate.

When the control unit 100 determines in step SG6 that the amount of rotation of the bit moving motor 50 has reached the set value selected by the setting unit 110 and that the tip of the driver bit 2 has reached the set operation end position P2, step SG8. The driving of the bit rotating motor 40 is stopped at step SG9, and after stopping the forward rotation of the bit moving motor 50 at step SG9, the bit moving motor 50 is reversed at step SG10.

When the bit moving motor 50 rotates in the opposite direction, the pulley 52 rotates in the opposite direction, the wire 54 is pulled out from the pulley 52, and the second moving member 32c is pushed by the biasing member 33 to move. The holding member 30 connected to the member 32 and the moving member 32 by the first moving member 32a moves backward.

In step SG11, the control unit 100 rotates the bit moving motor 50 in reverse to the initial position where the wire 54 is pulled out from the pulley 52 by a predetermined amount, and rotates the holding member 30 and the moving member until the tip of the driver bit 2 returns to the standby position P1. 32 moves backward, the reverse rotation of the bit moving motor 50 is stopped in step SG12.

If the bit rotating motor 40 and the bit moving motor 50 rotate in the forward direction with the screw 200 not in the ejection port 80, the bit rotating motor 40 and the bit moving motor 50 will not press the screw 200 against the object to be fastened. does not increase the load on For this reason, even if the driver bit 2 attached to the holding member 30 advances by a specified amount of movement based on the length of the minimum screw 200 to be loaded, if a predetermined load is not detected, the screw 200 will not move. I can judge no.

Therefore, in step SG13, the control unit 100 sets a specified amount of movement based on the length of the minimum screw 200 to be loaded, a specified amount of idling detection by which the driver bit 2 attached to the holding member 30 advances, and a bit movement. Determine whether the motor 50 has rotated. Then, the control unit 100 determines that either or both of the bit rotating motor 40 and the bit moving motor 50 do not detect a predetermined load, and that the bit moving motor 50 rotates by the stipulated rotation detection amount. Upon determination, it is determined that there is no screw 200, and an error is notified in step SG14. Further, the driving of the bit rotating motor 40 and the bit moving motor 50 is stopped in the processing of steps SG8 to SG12 described above.

The control unit 100 may detect the load applied to either the bit rotating motor 40 or the bit moving motor 50, or both, by detecting changes in the current flowing through the motors, excluding current changes that occur when the motors are started. Alternatively, it may be detected by a change in the voltage flowing through the motor except for a voltage change that occurs when the motor is started. It should be noted that the rotation of the bit holding part 3 and the movement of the bit holding part 3 in the axial direction may be performed by a single motor. You may suppress the drive in the state without.

Reference Signs List 1 Fastening tool 10 Tool body 10a Case 10b Front frame 10c Rear frame 10d Coupling member 10e Screw 10f Nose main body 11 Handle 12 Battery 13 Battery mounting portion 2 Driver bit 3 Bit holding portion 30 Holding member 30a opening 30b connecting member 31 rotation guide member 31a groove 32 moving member 32a first moving member 32b bearing 32c... second moving member, 33... urging member, 34a... bearing (bearing), 4... first driving section, 40... bit rotating motor (motor, first Motor), 40a... Shaft, 41... Reducer, 41a... Shaft, 42... Bearing (bearing), 5... Second driving section, 50... Bit moving motor (motor , second motor), 50a... Shaft, 51... Reducer, 51a... Shaft, 52... Pulley (transmission member), 53... Bearing, 54... Wire (transmission member ), 6...screw storage portion, 7...screw feed portion, 70...screw feed motor, 71...pinion gear, 72...rack gear, 73...engagement portion, 8... Nose portion 80 Ejection passage 81 Contact member 81a Ejection port 82 Contact arm 83 Adjusting portion 84 Contact switch portion 9 Trigger 90 Trigger switch section 100 Control section 110 Setting section

Claims (8)

a bit holding portion that detachably holds the driver bit and is rotatable in the circumferential direction and movable in the axial direction of the driver bit;
a motor that rotates the bit holder and moves the bit holder along the axial direction;
a control unit that controls the position of the bit holding unit along the axial direction by the amount of rotation of the motor;
The control unit stops the rotation of the motor based on the load applied to the motor rotated in one direction that moves the bit holding unit closer to the fastening object. The fastening tool according to claim 1, wherein, after stopping the rotation of the motor, the control section rotates the motor in another direction to move the bit holding section away from the fastening object. The fastening tool according to claim 1 or 2, wherein the controller notifies that there is an abnormality when stopping the rotation of the motor. The fastening tool according to any one of claims 1 to 3, wherein the control unit determines whether or not there is a screw based on the load applied to the motor, and stops rotation of the motor when determining that there is no screw. . 5. The control unit determines the presence or absence of a screw based on the amount of movement based on the minimum screw length and the load applied to the motor when the bit holding unit moves in one direction. fastening tool. The fastening tool according to any one of claims 1 to 5, wherein the load applied to the motor is detected by a change in the current flowing through the motor except for a current change that occurs when the motor is started. The fastening tool according to any one of claims 1 to 5, wherein the load applied to the motor is detected by a change in voltage flowing through the motor, excluding a voltage change that occurs when the motor is started. the motor includes a first motor that rotates the bit holding portion;
a second motor for moving the bit holding part along the axial direction,
The control unit rotates the load applied to the first motor that rotates the bit holding unit in one direction to tighten the screw, or rotates the bit holding unit in one direction that moves the bit holding unit closer to the object to be fastened. The fastening according to any one of claims 1 to 7, wherein the rotation of the first motor and the second motor is stopped based on one or both of the loads applied to the second motor caused by the tool.

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