JP6105445B2 - Work tools - Google Patents

Description

  The present invention relates to a work tool that rotationally drives a tip tool.

  Japanese Patent Application Laid-Open No. 2012-135842 describes a screw driver that rotationally drives a driver bit. The screw driver is configured to transmit the rotation of the drive gear to the spindle by pushing the roller holding member while the roller rotates during the screw tightening operation.

JP 2012-135842 A

  However, in the screw driver, since the roller presses the roller holding member while rotating, the roller and the roller holding member may be worn by the rotation of the roller. Therefore, the present invention has been made in view of the above, and an object thereof is to provide a technique for rationally transmitting the rotation of a motor to a tip tool in a work tool.

  The above object is achieved by the invention described in claim 1. According to the preferable form of the work tool which concerns on this invention, the work tool which rotationally drives a front-end tool is comprised. The work tool includes a motor having an output shaft and a rotation transmission mechanism that transmits the rotation of the output shaft to the tip tool. The rotation transmission mechanism has a rotating shaft, is driven by a motor, is disposed coaxially with the rotating shaft, and is connected to a tip tool, and is interposed between the driving member and the driven member. And the transmission position for transmitting the rotation of the driving member to the driven member with respect to the circumferential direction of the rotating shaft, and the position different from the transmission position, and the rotation of the driving member cannot be transmitted to the driven member. A transmission member movable between non-transmission positions, and a switching member configured to switch the transmission member between the transmission position and the non-transmission position by moving relative to the driven member in the circumferential direction; Have The driven member is configured to be movable between the first position and the second position in the axial direction in which the rotation shaft extends. The transmission member is configured to be switched between the transmission position and the non-transmission position by allowing relative movement of the switching member in the circumferential direction based on the position of the driven member in the axial direction.

  According to the present invention, since the transmission member is switched between the transmission position and the non-transmission position in the circumferential direction of the rotating shaft, the position of the transmission member is rationally switched with respect to the rotating drive member. As a result, the rotation of the drive member is rationally transmitted to the tip tool.

  According to the further form of the working tool which concerns on this invention, it is comprised so that a to-be-driven member may move to a 2nd position from a 1st position because a front-end tool is pressed with respect to a workpiece. . When the output member rotates in the predetermined first direction and the driven member is positioned at the first position, the relative movement of the switching member in the circumferential direction is restricted, and the switching member cannot transmit the transmission member. Configured to hold in position. Further, when the driven member is moved from the first position to the second position when the output shaft rotates in the predetermined first direction, the relative movement of the switching member in the circumferential direction is permitted, and the switching member is By switching the transmission member to the transmission position, the rotation of the output shaft in the first direction is transmitted to the driven member via the transmission member. On the other hand, when the output member rotates in the second direction opposite to the first direction, if the driven member is positioned at the first position, the relative movement of the switching member in the circumferential direction is allowed and the switching is performed. When the member switches the transmission member to the transmission position, the rotation of the output shaft in the second direction is transmitted to the driven member via the transmission member.

  According to this embodiment, the driving of the tip tool is switched according to the rotation direction of the output shaft of the motor and the position of the driven member. Therefore, the work tool is rationally driven according to the work mode. Further, the driving of the tip tool due to the operator's erroneous operation is suppressed.

  According to the further form of the working tool which concerns on this invention, it has the axial direction movement element which moves to the said axial direction with the movement of the driven member regarding an axial direction. The axial movement element is configured to move the switching member in the circumferential direction when the axial movement element moves in the axial direction. The axial movement element may be formed integrally with the driven member, or on the other hand, may be formed separately from the driven member. When formed separately, the axial movement element is preferably formed as a spherical member.

  According to this embodiment, the movement in the axial direction is converted into the movement in the circumferential direction by moving the switching member in the circumferential direction by the axial movement element. Therefore, the switching member is rationally moved in the circumferential direction by the axial movement of the driven member during operation.

  According to the further form of the working tool which concerns on this invention, the axial direction movement element is comprised so that the relative movement of the switching member regarding a circumferential direction may be controlled normally. Then, when the driven member is moved from the first position to the second position, the axial movement element is moved in the axial direction to allow relative movement of the switching member in the circumferential direction. . The switching member is configured to switch the transmission member from the non-transmissible position to the transmission position by rotating the drive member in a state where the relative movement of the switching member is allowed.

  According to this embodiment, since the axial movement element is configured to restrict the relative movement of the switching member in the circumferential direction at all times, malfunction of the work tool is suppressed. Further, the driving of the tip tool due to the operator's erroneous operation is suppressed.

  According to the further form of the working tool which concerns on this invention, the said working tool is comprised as a screw fastening tool which rotates a screw with a front-end tool and performs a screw fastening operation | work with respect to a workpiece. Furthermore, it has the workpiece contact part which can contact | abut to a workpiece at the time of a screw fastening operation | work. Then, in a state where the workpiece contact portion is in contact with the workpiece, the tip tool screws the screw into the workpiece, so that the driven member connected to the tip tool approaches the workpiece in the axial direction. Is configured to move. Further, as the driven member moves in the axial direction during the screw tightening operation, the axial moving element moves in the axial direction, so that the axial moving element moves the switching member in the circumferential direction. The transmission member is configured to switch from the transmission position to the non-transmission position. The workpiece contact portion may be the tool body itself that houses the drive mechanism or the like, or may be a member attached to the tool body.

  According to this embodiment, since the work tool is configured as a screw tightening tool, the transmission member is switched to a non-transmittable position when the amount of screw movement by screwing exceeds a predetermined amount during the screw tightening operation. Therefore, when the screw is screwed in by a predetermined amount, the work tool automatically stops and the screwing amount of the screw becomes constant.

  According to the further form of the working tool which concerns on this invention, one component of the axial direction movement element and the switching member has the guidance | induction part extended in the circumferential direction, and switches with an axial direction movement element. The other component of the member has a contact portion that can contact the guide portion. During the screw tightening operation, the switching member is moved in the circumferential direction by moving the axial movement element so as to approach the workpiece in the axial direction in a state where the guide portion and the contact portion are in contact with each other. It is configured. Furthermore, the switching member is configured to switch the transmission member from the transmission position to the non-transmission position by moving the switching member in the circumferential direction. It is preferable that at least one component of the guide portion and the contact portion has an inclined portion that is inclined with respect to the axial direction. That is, the movement in the axial direction is converted into the movement in the circumferential direction by the inclined portion by moving in the axial direction while the other component is in contact with the inclined portion.

  According to this embodiment, the axial movement of the axial movement element is converted into the circumferential movement of the switching member by the guide portion and the contact portion.

  According to the further form of the work tool which concerns on this invention, the part which opposes the other member of one member among a drive member and a driven member is formed in the cylindrical shape, and one member of the other member is formed in one member. Opposing portions are formed in a polygonal column shape. And the transmission member is comprised by the several transmission element arrange | positioned corresponding to each surface of a polygonal column.

  According to this form, a transmission member is pinched | interposed into a cylindrical member and a polygonal member by the wedge effect by arrange | positioning a transmission member between a cylindrical part and a polygonal part. Thereby, rotation of a drive member is rationally transmitted to a driven member via a transmission member.

  According to the further form of the working tool which concerns on this invention, a driven member is arrange | positioned inside a drive member, and the inner side of a drive member is formed in the cylindrical shape. On the other hand, the outer side of the driven member is formed in a polygonal column shape. Moreover, the transmission element is formed in a roller shape and is arranged corresponding to each surface of the polygonal column formed on the driven member. In addition, as a roller-shaped transmission element, any shape of a cylindrical shape and a conical shape is included suitably.

  According to this embodiment, since the transmission member is formed in a roller shape, the transmission member moves between the transmission position and the non-transmission position while rolling. Therefore, the influence of friction on the movement of the transmission member is reduced.

  According to the further form of the work tool which concerns on this invention, when an output shaft rotates to a 1st direction, an operator presses a front-end tool with respect to a workpiece, among several transmission elements. The first group of transmission elements is configured to be switched from the transmission impossible position to the transmission position. On the other hand, when the output shaft rotates in the second direction, the operator does not press the tip tool toward the workpiece, and the first group of transmission elements is held in the non-transmittable position. The transmission elements of the second group other than the transmission elements of one group are configured to be switched from the transmission impossible position to the transmission position.

  According to this embodiment, since the transmission member is composed of a plurality of transmission elements, the transmission elements of the first group and the transmission elements of the second group can be used properly. That is, depending on the rotation direction of the output shaft of the motor, the transmission elements to be used can be used properly.

  According to the present invention, a technique for rationally transmitting the rotation of a motor to a tip tool is provided.

It is sectional drawing which shows the whole structure of the screwdriver which concerns on 1st Embodiment. It is a fragmentary sectional view of a screw driver. It is sectional drawing in the III-III line of FIG. It is a perspective view of a retainer and a ball. It is sectional drawing which shows the groove | channel of the retainer in the VV line | wire of FIG. It is sectional drawing in the VI-VI line of FIG. It is sectional drawing equivalent to FIG. 2 at the time of screw fastening operation | work. It is sectional drawing of the groove | channel equivalent to FIG. 5 at the time of screwing operation | work. It is sectional drawing in the IX-IX line of FIG. It is sectional drawing of the groove | channel equivalent to FIG. 5 at the time of screwing operation | work. FIG. 6 is a cross-sectional view of a groove corresponding to FIG. It is sectional drawing of the groove | channel equivalent to FIG. 5 at the time of screw removal operation | work. FIG. 6 is a cross-sectional view corresponding to FIG. 5 during a screw removing operation. It is sectional drawing of the groove | channel equivalent to FIG. 5 in a modification. It is sectional drawing of the screwdriver which concerns on 2nd Embodiment. It is sectional drawing in the XVI-XVI line | wire of FIG. It is a perspective view of a retainer and a ball. It is sectional drawing which shows the groove | channel of a retainer. It is sectional drawing in the XIX-XIX line | wire of FIG. FIG. 16 is a cross-sectional view corresponding to FIG. 15 during a screw tightening operation. It is sectional drawing of the groove | channel equivalent to FIG. 18 at the time of screwing operation | work. It is sectional drawing in the XXII-XXII line | wire of FIG. It is sectional drawing of the screwdriver which concerns on 3rd Embodiment. It is sectional drawing in the XXIV-XXIV line | wire of FIG. It is a perspective sectional view of a retainer and a transmitted member. It is sectional drawing which shows the groove | channel of a retainer. It is sectional drawing in the XXVII-XXVII line of FIG. It is sectional drawing equivalent to FIG. 23 at the time of screw fastening operation | work. FIG. 26 is a perspective cross-sectional view corresponding to FIG. 25 during a screw tightening operation. It is sectional drawing equivalent to FIG. 26 at the time of screw fastening operation | work. It is sectional drawing in the XXXI-XXXI line | wire of FIG. It is sectional drawing of the screwdriver which concerns on 4th Embodiment. It is sectional drawing in the XXXIII-XXXIII line | wire of FIG. It is a perspective view of a retainer and a ball. It is sectional drawing which shows the groove | channel of a retainer. It is a perspective view of a retainer, a roller, and a to-be-transmitted member. It is a side view of a retainer and a roller. It is sectional drawing in the XXXVIII-XXXVIII line | wire of FIG. It is sectional drawing equivalent to FIG. 32 at the time of screw fastening operation | work. FIG. 36 is a cross-sectional view of a groove corresponding to FIG. 35 during a screw tightening operation. It is sectional drawing in the XLI-XLI line | wire of FIG. It is sectional drawing in the XLII-XLII line | wire of FIG. It is sectional drawing equivalent to FIG. 41 at the time of screw removal operation | work. It is a side view equivalent to FIG. 37 at the time of screw removal work.

[First Embodiment]
A first embodiment will be described with reference to FIGS. As shown in FIG. 1, a screw driver 100 that performs a screw tightening operation on a workpiece such as a gypsum board is configured as an example of a work tool. The screw driver 100 is mainly composed of a main body 101 and a handle 107.

  The main body 101 is mainly composed of a main body housing 103 and a locator 105. The main body housing 103 accommodates the motor 110 and the drive mechanism 120. The locator 105 is attached to the tip region of the main body housing 103. A tool bit 119 is detachably attached to the drive mechanism 120 at the distal end region of the main body 101. The tool bit 119 protrudes from the locator 105 and is attached to the locator 105 so as to be relatively movable in the major axis direction of the tool bit 119.

  The handle 107 is connected to the rear end region of the main body 101. The handle 107 is provided with a trigger 107a and a changeover switch 107b. When the trigger 107a is operated, a current is supplied from the power cord 109, and the motor 110 is driven. Further, the rotation direction of the output shaft 111 of the motor 110 is switched by operating the changeover switch 107b. That is, the output shaft 111 is driven by selecting one of the rotation directions of forward rotation and reverse rotation. The motor 110 and the output shaft 111 are implementation configuration examples corresponding to the “motor” and the “output shaft” in the present invention, respectively.

  As shown in FIGS. 2 to 6, the drive mechanism 120 is mainly configured by a drive gear 125, a retainer 130, a transmission mechanism 140, a coil spring 145, and a spindle 150. This drive mechanism 120 is an implementation structural example corresponding to the "rotation transmission mechanism" in this invention.

  As shown in FIGS. 2 and 3, the drive gear 125 is a substantially cup-shaped member having a side wall 126 and a bottom wall 127. The inner side of the side wall 126 is formed in a cylindrical shape, so that the drive gear 125 accommodates the retainer 130 and the transmission mechanism 140. The side wall 126 is provided with gear teeth 126 a that engage with the gear teeth 112 formed on the output shaft 111 of the motor 110. On the other hand, a through-hole through which the spindle 150 passes is provided at the center of the bottom wall 127. In the vicinity of the through hole, an abutting portion 127a that can abut on the retainer 130 is provided. That is, the drive gear 125 and the retainer 130 are in contact with each other via the contact portion 127a, and are not in contact with each other except the contact portion 127a. The drive gear 125 is rotatably held by a bearing 128. The drive gear 125 is arranged so as to be movable in the long axis direction of the spindle 150 (the long axis direction of the tool bit 119). This drive gear 125 is an implementation configuration example corresponding to the “drive member” in the present invention.

  As shown in FIG. 4, the retainer 130 is formed in a substantially cylindrical shape, and has a base portion 131 that faces the bottom wall 127 of the drive gear 125 and a side portion 136 that faces the side wall 126 of the drive gear 125. Yes. In FIG. 4, components other than the retainer 130 and the ball 143 are not shown.

  As shown in FIG. 4, two grooves 132 are formed in the base 131 along the circumferential direction of the retainer 130. As shown in FIG. 5, each groove 132 is formed with a flat portion 133 parallel to the base portion 131, an inclined portion 134 inclined with respect to the flat portion 133, and a vertical portion 135 perpendicular to the flat portion 133. Has been. The groove 132 is configured to contact the ball 143. In FIG. 5, only the ball 143 in contact with the groove 132 among the three balls 143 is illustrated. Hereinafter, the same applies to the sectional views of the grooves.

  The side portion 136 is formed so as to protrude from the base portion 131 in parallel with the axial direction of the cylindrical retainer 130. With respect to the circumferential direction of the retainer 130, six side portions 136 are formed at intervals from each other, and the roller 141 is disposed between the adjacent side portions 136. As shown in FIGS. 2 and 3, the end portion of the side portion 136 in the axial direction of the retainer 130 is supported by a needle bearing 137, and thereby the retainer 130 is rotatably supported. This retainer 130 is an implementation structural example corresponding to the "switching member" in this invention.

  As shown in FIGS. 2 and 3, the transmission mechanism 140 is composed mainly of a roller 141, a member to be transmitted 142, and a ball 143. The transmission mechanism 140 is configured to transmit the rotation of the drive gear 125 to the spindle 150. As shown in FIG. 6, the transmitted member 142 has a regular hexagonal cross-sectional shape. Six rollers 141 are arranged on the outer periphery of the member to be transmitted 142 corresponding to the sides of the regular hexagon of the member to be transmitted 142. In the roller 141, the major axis direction of the roller 141 is arranged along the major axis direction of the spindle 150. When the retainer 130 rotates, the roller 141 is moved in the circumferential direction along the outer periphery of the transmitted member 142 by the side portion 136 of the retainer 130. This roller 141 is an implementation configuration example corresponding to the “transmission member” and “transmission element” of the present invention.

  As shown in FIG. 2, the ball 143 is held inside the transferred member 142 by a ball holding groove 142 a formed in the transferred member 142 and a ball holding groove 156 of the spindle 150. As a result, the transmitted member 142 and the spindle 150 rotate together via the ball 143. Three balls 143 are arranged in the ball holding grooves 142 a so as to be movable in the long axis direction of the spindle 150. Note that a movement restricting portion 142 b is formed in the transmitted member 142 and restricts the movement of the ball 143 over a predetermined distance in the major axis direction of the spindle 150.

  As shown in FIGS. 2 and 3, the spindle 150 is integrally formed with a substantially cylindrical bit holding portion 151 and a substantially columnar rotation transmission shaft 155. A bit holding ball 152 and a leaf spring 153 are disposed in the bit holding portion 151, and thereby the tool bit 119 is detachably held. A flange portion 154 is formed on the opposite side of the bit holding portion 151 from the tool bit 119 with respect to the long axis direction of the spindle 150. The flange portion 154 is disposed so as to face the drive gear 125.

  One end side of the rotation transmission shaft 155 is connected to the bit holding portion 151, and the other end side passes through the drive gear 125 and extends to the motor 110 side. The rotation transmission shaft 155 is formed with two ball holding grooves 156 for holding the balls 143 corresponding to the two ball holding grooves 142 a on the member to be transmitted 142. The ball holding groove 156 extends in the long axis direction of the rotation transmission shaft 155 (the long axis direction of the spindle 150).

  The above spindle 150 is rotatably held by a bearing 159. The spindle 150 is held so as to be movable in the major axis direction of the spindle 150. The spindle 150 is an implementation configuration example corresponding to the “driven member” in the present invention.

  As shown in FIGS. 2 and 3, the coil spring 145 is disposed outside the rotation transmission shaft 155 and parallel to the long axis direction of the spindle 150. One end of the coil spring 145 contacts the drive gear 125, and the other end of the coil spring 145 contacts the spindle 150. As a result, the spindle 150 is biased toward the side on which the tool bit 119 is mounted (front of the screw driver 100). A stopper 146 is disposed in front of the flange portion 154. Therefore, the contact of the flange portion 154 and the stopper 146 restricts the movement of the spindle 150 forward of the screw driver 100. On the other hand, the drive gear 125 is biased by the coil spring 145 toward the side opposite to the side on which the tool bit 119 is mounted (rear side of the screw driver 100). At this time, the drive gear 125 is restricted from moving backward by the screw driver 100 by the retainer 130 and the needle bearing 137.

  In the screw driver 100 configured as described above, when the trigger 107a is operated, the motor 110 is driven. The drive gear 125 is rotated by the rotation of the output shaft 111 of the motor 110. Then, the rotation of the drive gear 125 is transmitted to the spindle 150, whereby the tool bit 119 held on the spindle 150 is rotated.

(Screw tightening work)
When the output shaft 111 of the motor 110 rotates in a predetermined direction (hereinafter referred to as a positive direction), as shown in FIG. 2, the rotational force of the drive gear 125 is transmitted to the retainer 130 by the frictional force via the contact portion 127a. However, as shown in FIGS. 2 and 5, the ball 143 is in contact with the inclined portion 134 of the retainer 130, thereby preventing the ball 143 from rotating the retainer 130. Therefore, even if the drive gear 125 is rotated, the rotation of the drive gear 125 is not transmitted to the retainer 130. That is, the roller 141 is held at the position shown in FIG. 6, and the spindle 150 is not rotated. The rotation direction of the output shaft 111 during the screw tightening operation is an implementation configuration example corresponding to the “first direction” in the present invention. The position of the roller 141 shown in FIG. 6 is an implementation configuration example corresponding to the “non-transmittable position” in the present invention.

  On the other hand, as shown in FIG. 7, when the tool bit 119 is pressed against a screw (not shown), the spindle 150 moves rearward of the screw driver 100 against the urging force of the coil spring 145. As the spindle 150 moves, the ball 143 moves backward. As a result, as shown in FIGS. 8 and 9, the contact between the ball 143 and the inclined portion 134 is released, and the retainer 130 is moved in the direction indicated by the arrow A by the frictional force between the contact portion 127 a and the retainer 130 ( A direction). The position on the front side and the position on the rear side of the spindle 150 are implementation examples corresponding to the “first position” and the “second position” in the present invention, respectively. Further, the position of the roller 141 shown in FIG. 9 is an implementation configuration example corresponding to the “transmission position” in the present invention.

  The roller 141 is moved by the rotation of the retainer 130, and the roller 141 is sandwiched between the drive gear 125 and the transmitted member 142. As a result, the driving gear 125 and the transmitted member 142 are integrally rotated in the A direction by the wedge effect of the roller 141. In other words, the rotation of the drive gear 125 is transmitted to the transmitted member 142. The rotation transmission shaft 155 (spindle 150) is rotated by the rotation of the transmitted member 142. As a result, the tool bit 119 held on the spindle 150 rotates and the screw tightening operation is performed.

  When the screwing operation is performed, the screw is screwed into the workpiece. When the front surface of the locator 105 comes into contact with the workpiece as the screw to be screwed moves, the spindle 150 holding the tool bit 119 gradually moves toward the front of the screw driver 100. As a result, the ball 143 held in the ball holding groove 156 moves forward. That is, the ball 143 moves from the position shown in FIG. 8 to the position shown in FIG. 10 and comes into contact with the inclined portion 134 of the groove 132 provided in the retainer 130. This locator 105 is an implementation configuration example corresponding to the “workpiece contact portion” in the present invention.

  Furthermore, when the screw is screwed into the workpiece and the spindle 150 moves toward the front of the screw driver 100, the ball 143 presses the inclined portion 134 as shown in FIG. As a result, as shown in FIG. 9, the retainer 130 rotates relative to the B direction with respect to the drive gear 125 rotating in the A direction. As a result, the retainer 130 and the roller 141 are moved to the positions shown in FIG. 6, and the transmission of the rotation of the drive gear 125 to the member to be transmitted 142 is interrupted. As a result, the screw is screwed into the workpiece to a predetermined depth, and the screw tightening operation is completed. The distance between the screw head held by the tool bit 119 and the front surface of the locator 105 as a predetermined depth into which the screw is screwed can be changed by the operator. The ball 143 and the inclined portion 134 of the groove 132 are implementation configuration examples corresponding to the “contact portion” and the “guide portion” in the present invention, respectively.

(Screw removal work)
During the unscrewing operation for removing the screw screwed into the workpiece, the screw driver 100 reverses the screw to remove the screw from the workpiece. At this time, in order to drive the tool bit 119, it is not reasonable for the tool bit 119 to press the screw. Therefore, in the screw driver 100, the tool bit 119 is driven by the motor 110 without pressing the tool bit 119 in the screw removing operation.

  Specifically, the changeover switch 107b is switched so that the output shaft 111 of the motor 110 rotates in the direction opposite to the forward direction in the screw tightening operation (hereinafter referred to as the reverse direction). In the state shown in FIG. 2, when the motor 110 is driven, the drive gear 125 transmits the rotation of the drive gear 125 to the retainer 130 by frictional force through the contact portion 127a. At this time, the retainer 130 moves from the state shown in FIG. 5 in the direction B as shown in FIG. That is, the ball 143 moves away from the inclined portion 134 of the groove 132 of the retainer 130 in a direction approaching the vertical portion 135. In other words, the ball 143 does not hinder the rotation of the retainer 130. The rotation direction of the output shaft 111 at the time of the screw removal work is an implementation configuration example corresponding to the “second direction” in the present invention.

  As the retainer 130 rotates in the B direction, the roller 141 is moved as shown in FIG. 13, and the roller 141 is sandwiched between the drive gear 125 and the transmitted member 142. As a result, the driving gear 125 and the transmitted member 142 are integrally rotated in the B direction by the wedge effect of the roller 141. As a result, the tool bit 119 is driven without pressing the tool bit 119 against the screw. Therefore, the unscrewing operation is reasonably performed. The position of the roller 141 shown in FIG. 13 is an implementation configuration example corresponding to the “transmission position” in the present invention.

  Further, according to the first embodiment, the rotation of the drive gear 125 in both the A direction and the B direction is transmitted by the same roller 141. That is, when the drive gear 125 rotates in the A direction, the tool bit 119 and the spindle 150 are moved in the axial direction, so that the rotation of the drive gear 125 is transmitted to the spindle 150 via the roller 141. On the other hand, when the drive gear 125 rotates in the B direction, the rotation of the drive gear 125 is transmitted to the spindle 150 via the roller 141 without moving the tool bit 119 and the spindle 150 in the axial direction. Therefore, based on a rational work mode, the same roller 141 transmits the rotation of the motor 110 to the tool bit 119.

[Modification of First Embodiment]
In the first embodiment, the tool bit 119 is driven without pressing the tool bit 119 against the screw during the screw removal operation. On the other hand, unlike the first embodiment, the tool bit 119 may be configured to be driven by pressing the tool bit 119 against the screw during the screw removal operation.

  Specifically, as shown in FIG. 14, an inclined portion 134 is formed in the groove 132 of the retainer 130 instead of the vertical portion 135. Accordingly, when the tool bit 119 is not pressed against the screw, the movement of the retainer 130 in both the A direction and the B direction is restricted by the contact between the ball 143 and the inclined portion 134. That is, it is necessary to press the tool bit 119 against the screw in order to drive the tool bit 119 in both the screw tightening operation and the screw removing operation.

[Second Embodiment]
Next, a second embodiment will be described with reference to FIGS. Of the screw driver 200, the same configurations as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and description thereof is omitted.

  As shown in FIGS. 15 to 19, the drive mechanism 220 is mainly composed of a drive gear 225, a retainer 230, a transmission mechanism 240, a coil spring 145, and a spindle 150. This drive mechanism 220 is an implementation structural example corresponding to the "rotation transmission mechanism" in this invention.

  As shown in FIGS. 15 and 16, the drive gear 225 is a substantially cup-shaped member having a side wall 226 and a bottom wall 227. The inner side of the side wall 226 is formed in a cylindrical shape, so that the drive gear 225 accommodates the retainer 230 and the transmission mechanism 240. The side wall 226 is provided with gear teeth 226 a that engage with the gear teeth 112 formed on the output shaft 111 of the motor 110. On the other hand, a through-hole through which the spindle 150 and the coil spring 145 pass is provided at the center of the bottom wall 227. In the vicinity of the through hole, a contact portion 227a that can contact the retainer 230 is provided. That is, the drive gear 225 and the retainer 230 are in contact with each other via the contact portion 227a and are not in contact with each other except the contact portion 227a. The drive gear 225 is disposed so as to be movable in the long axis direction of the spindle 150 (the long axis direction of the tool bit 119). In addition, a stopper 229 is provided in front of the drive gear 225, and movement of the drive gear 225 to the front of the screw driver 200 is restricted. This drive gear 225 is an implementation structural example corresponding to the "drive member" in this invention.

  As shown in FIG. 17, the retainer 230 is formed in a substantially cylindrical shape, and has a base portion 231 that faces the bottom wall 227 of the drive gear 225 and a side portion 236 that faces the side wall 226 of the drive gear 225. Yes. In FIG. 17, components other than the retainer 230 and the ball 143 are not shown.

  As shown in FIG. 17, two grooves 232 are formed in the base portion 231 along the circumferential direction of the retainer 230. As shown in FIG. 18, each groove 232 is formed by an inclined portion 234 that is inclined with respect to the base portion 231. Moreover, the side part 236 is formed so that it may protrude in parallel with the axial direction of the cylindrical retainer 230 from the base part 231 similarly to 1st Embodiment. This retainer 230 is an implementation structural example corresponding to the "switching member" in this invention.

  As shown in FIGS. 15 and 16, the transmission mechanism 240 is composed mainly of a roller 141, a member to be transmitted 242, and a ball 143. As shown in FIG. 19, the transmitted member 242 has a regular hexagonal cross-sectional shape. Similar to the first embodiment, six rollers 141 are arranged on the outer periphery of the transmitted member 242 corresponding to each side of the regular hexagon of the transmitted member 242. In FIG. 19, the components outside the drive gear 225 are not shown. The same applies to the sectional views of the drive gear, the retainer and the like thereafter.

  As shown in FIG. 15, the ball 143 is held inside the transferred member 242 by a ball holding groove 242 a formed in the transferred member 242 and a ball holding groove 156 of the spindle 150. As a result, the transmitted member 242 and the spindle 150 rotate together via the ball 143.

  As shown in FIGS. 15 and 16, the coil spring 145 is disposed outside the rotation transmission shaft 155 and parallel to the long axis direction of the spindle 150. One end of the coil spring 145 passes through the drive gear 225 and contacts the retainer 230, and the other end of the coil spring 145 contacts the spindle 150. As a result, the spindle 150 is biased toward the side on which the tool bit 119 is mounted (front of the screw driver 200). The movement of the spindle 150 forward of the screw driver 200 is restricted by the contact between the ball holding groove 156 and the ball 143 and the contact between the retainer 230 and the ball 143. The retainer 230 is restricted from moving forward by the screw driver 200 by the stopper 229 via the drive gear 225. On the other hand, the retainer 230 is biased by the coil spring 145 toward the side opposite to the side on which the tool bit 119 is mounted (rear side of the screw driver 200). At this time, the retainer 230 is restricted from moving rearward of the screw driver 200 by the needle bearing 137.

(Screw tightening work)
As shown in FIG. 20, when the tool bit 119 is pressed against a screw (not shown), the spindle 150 moves rearward of the screw driver 200 against the urging force of the coil spring 145. As the spindle 150 moves, the ball 143 moves backward. Accordingly, as shown in FIGS. 21 and 22, the contact between the ball 143 and the inclined portion 234 is released, and the bottom wall 227 of the drive gear 225 pressed by the flange portion 154 of the spindle 150 causes the contact portion 227 a to move. The retainer 230 is rotated. That is, the retainer 230 is rotated in the direction indicated by the arrow A (direction A) by the frictional force between the contact portion 227a and the retainer 230.

  The roller 141 is moved by the rotation of the retainer 230, and the roller 141 is sandwiched between the drive gear 225 and the transmitted member 242. As a result, the drive gear 225 and the transmitted member 242 are integrally rotated in the A direction by the wedge effect of the roller 141. As a result, the tool bit 119 held on the spindle 150 rotates and the screw tightening operation is performed.

  When the spindle 150 moves toward the front of the screw driver 200 by screwing the screw into the workpiece, the ball 143 presses the inclined portion 234 as in the first embodiment. Thereby, the retainer 230 rotates relative to the B direction with respect to the drive gear 225 rotating in the A direction. As a result, the retainer 230 and the roller 141 move to the position shown in FIG. 19 and the transmission of the rotation of the drive gear 225 to the member to be transmitted 242 is interrupted. As a result, the screw is screwed into the workpiece to a predetermined depth, and the screw tightening operation is completed. The inclined portion 234 of the groove 232 is an implementation configuration example corresponding to the “guidance portion” in the present invention.

(Screw removal work)
In the second embodiment, the unscrewing operation is configured such that the tool bit 119 is driven by pressing the tool bit 119 against the screw in the same manner as the screw tightening operation. In the screw removal operation, the drive gear 225 is rotated in the B direction.

[Third Embodiment]
Next, a third embodiment will be described with reference to FIGS. In the screw driver 300, the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted.

  As shown in FIGS. 23 to 27, the drive mechanism 320 is mainly composed of a drive gear 325, a retainer 330, a transmission mechanism 340, a coil spring 145, and a spindle 150. This drive mechanism 320 is an implementation structural example corresponding to the "rotation transmission mechanism" in this invention.

  As shown in FIGS. 23 and 24, the drive gear 325 is a substantially cup-shaped member having a side wall 326 and a bottom wall 327. The inside of the side wall 326 is formed in a cylindrical shape, whereby the drive gear 325 accommodates the retainer 330 and the transmission mechanism 340. The side wall 326 is provided with gear teeth 326 a that engage with the gear teeth 112 formed on the output shaft 111 of the motor 110. On the other hand, a through-hole through which the spindle 150 and the coil spring 145 pass is provided at the center of the bottom wall 327. In the vicinity of the through hole, an abutting portion 327a that can abut on the retainer 330 is provided. That is, the drive gear 325 and the retainer 330 are in contact with each other via the contact portion 327a, and are not in contact with each other except the contact portion 327a. The drive gear 325 is disposed so as to be movable in the long axis direction of the spindle 150 (the long axis direction of the tool bit 119). A stopper 329 is provided in front of the drive gear 325 to restrict the movement of the drive gear 325 to the front of the screw driver 300. This drive gear 325 is an implementation structural example corresponding to the "drive member" in this invention.

  As shown in FIG. 25, the retainer 330 is formed in a substantially cylindrical shape, and has a base portion 331 that faces the bottom wall 327 of the drive gear 325 and a side portion 336 that faces the side wall 326 of the drive gear 325. Yes. In FIG. 25, the components other than the retainer 330 and the transmitted member 342 are not shown.

  As shown in FIG. 25, a groove 332 is formed in the base 331 along the circumferential direction of the retainer 330. The grooves 332 are provided at two locations on the base 331. As shown in FIG. 26, each groove 332 is formed by an inclined portion 334 that is inclined with respect to the base portion 331. Moreover, the side part 336 is formed so that it may protrude in parallel with the axial direction of the cylindrical retainer 330 from the base part 331 similarly to 1st Embodiment. This retainer 330 is an implementation structural example corresponding to the "switching member" in this invention.

  As shown in FIG. 23 and FIG. 24, the transmission mechanism 340 is mainly composed of a roller 141 and a transmitted member 342. As shown in FIG. 27, the transmitted member 342 has a regular hexagonal cross-sectional shape. As in the first embodiment, six rollers 141 are arranged on the outer periphery of the transmitted member 342 so as to correspond to the sides of the regular hexagon of the transmitted member 342.

  As shown in FIGS. 23 and 25, the transmitted member 342 has two convex portions 343. The convex portion 343 is provided corresponding to the groove 332 of the retainer 330. A rotation transmission shaft 155 is press-fitted and fixed inside the transmitted member 342, whereby the spindle 150 and the transmitted member 342 rotate integrally. This convex part 343 is an implementation structural example corresponding to the "axial movement element" in this invention.

  As shown in FIGS. 23 and 24, the coil spring 145 is disposed outside the rotation transmission shaft 155 and parallel to the long axis direction of the spindle 150. One end of the coil spring 145 passes through the drive gear 325 and contacts the retainer 330, and the other end of the coil spring 145 contacts the spindle 150. As a result, the spindle 150 is biased toward the side on which the tool bit 119 is mounted (in front of the screw driver 300). A stopper 146 is disposed in front of the flange portion 154. Accordingly, the contact of the flange portion 154 and the stopper 146 restricts the movement of the spindle 150 forward of the screw driver 300. On the other hand, the retainer 330 is biased by the coil spring 145 toward the side opposite to the side on which the tool bit 119 is mounted (rear side of the screw driver 300). At this time, the retainer 330 is restricted from moving rearward of the screw driver 300 by the needle bearing 137.

(Screw tightening work)
As shown in FIG. 28, when the tool bit 119 is pressed against a screw (not shown), the spindle 150 moves rearward of the screw driver 300 against the urging force of the coil spring 145. That is, the transmitted member 342 moves rearward together with the spindle 150. As a result, as shown in FIGS. 29 to 31, the contact between the convex portion 343 and the inclined portion 334 is released, and the bottom wall 327 of the drive gear 325 pressed by the flange portion 154 of the spindle 150 becomes the contact portion 327 a. , The retainer 330 is rotated. That is, the retainer 330 is rotated in the direction indicated by the arrow A (direction A) by the frictional force between the contact portion 327a and the retainer 330.

  The roller 141 is moved by the rotation of the retainer 330, and the roller 141 is sandwiched between the drive gear 325 and the transmitted member 342. As a result, the drive gear 325 and the transmitted member 342 rotate integrally in the A direction due to the wedge effect of the roller 141. As a result, the tool bit 119 held on the spindle 150 rotates and the screw tightening operation is performed.

  When the spindle 150 moves toward the front of the screw driver 300 due to the screw being screwed into the workpiece, the convex portion 343 presses the inclined portion 334. The retainer 330 rotates in the B direction relative to the drive gear 325 that rotates in the A direction. As a result, the retainer 330 and the roller 141 move to the position shown in FIG. 27, and the transmission of the rotation of the drive gear 325 to the member to be transmitted 342 is interrupted. As a result, the screw is screwed into the workpiece to a predetermined depth, and the screw tightening operation is completed. The convex portion 343 and the inclined portion 334 of the groove 332 are implementation configuration examples corresponding to the “contact portion” and the “guidance portion” in the present invention, respectively.

(Screw removal work)
In the third embodiment, similarly to the screw tightening operation, the tool unloading operation is configured such that the tool bit 119 is driven by pressing the tool bit 119 against the screw. In the screw removal operation, the drive gear 325 is rotated in the B direction.

[Fourth Embodiment]
Next, a fourth embodiment will be described with reference to FIGS. In the screw driver 400, the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted.

  As shown in FIGS. 32 to 38, the drive mechanism 420 is mainly composed of a drive gear 425, a retainer 430, a transmission mechanism 440, a coil spring 145, and a spindle 150. This drive mechanism 420 is an implementation structural example corresponding to the “rotation transmission mechanism” in the present invention.

  As shown in FIGS. 32 and 33, the drive gear 425 is a substantially cup-shaped member having a side wall 426 and a bottom wall 427. The inner side of the side wall 426 is formed in a cylindrical shape, whereby the drive gear 425 accommodates the retainer 430 and the transmission mechanism 440. The side wall 426 is provided with gear teeth 426 a that engage with the gear teeth 112 formed on the output shaft 111 of the motor 110. On the other hand, a through-hole through which the spindle 150 passes is provided at the center of the bottom wall 427. In the vicinity of the through hole, an abutting portion 427a that can abut on the retainer 430 is provided. That is, the drive gear 425 and the retainer 430 are in contact with each other via the contact portion 427a, and are not in contact with each other other than the contact portion 427a. The drive gear 425 is disposed so as to be movable in the long axis direction of the spindle 150 (the long axis direction of the tool bit 119). This drive gear 425 is an implementation structural example corresponding to the "drive member" in this invention.

  As shown in FIG. 34, the retainer 430 is formed in a substantially cylindrical shape, and has a base portion 431 that faces the bottom wall 427 of the drive gear 425 and a side portion 435 that faces the side wall 426 of the drive gear 425. Yes. In FIG. 34, components other than the retainer 430 and the ball 143 are not shown. This retainer 430 is an implementation structural example corresponding to the "switching member" in this invention.

  As shown in FIG. 34, two grooves 432 are formed in the base portion 431 along the circumferential direction of the retainer 430. As shown in FIG. 35, each groove 432 is formed by an inclined portion 434 that is inclined with respect to the base portion 431.

  As shown in FIGS. 34 and 36, the side portion 435 is formed so as to protrude from the base portion 431 in parallel with the axial direction of the cylindrical retainer 430. The side portion 435 is configured by alternately arranging three wide portions 435a and three narrow portions 435b. The wide portion 435a is formed to be longer than the narrow portion 435b in the circumferential direction of the retainer 430.

  With respect to the circumferential direction of the retainer 430, first roller holding portions 436a and second roller holding portions 436b are alternately formed between the wide portions 435a and the narrow portions 435b. The first roller holding portion 436a is formed to be longer than the second roller holding portion 436b in the circumferential direction of the retainer 430. Further, the first roller holding portion 436 a is formed so as to penetrate the base portion 431 in the axial direction of the retainer 430.

  As shown in FIG. 36, the first roller 441a is disposed in the first roller holding portion 436a, and the second roller 441b is disposed in the second roller holding portion 436b. The first roller 441a is longer than the second roller 441b. As shown in FIG. 37, both end portions of the first roller 441a are formed in an arc shape. That is, the end portion of the first roller 441a is formed in an arc shape whose diameter is the length in the axial direction of the first roller 441a. The first roller 441a and the second roller 441b are an implementation configuration example corresponding to the “transmission member” in the present invention.

  As shown in FIG. 32 and FIG. 33, the transmission mechanism 440 is mainly configured by a first roller 441a, a second roller 441b, a transmitted member 442, and a ball 143. As shown in FIG. 38, the transmitted member 442 has a regular hexagonal cross-sectional shape.

  As shown in FIG. 32, the ball 143 is held inside the transferred member 442 in a ball holding groove 442 a formed in the transferred member 442 and a ball holding groove 156 of the spindle 150. As a result, the transmitted member 442 and the spindle 150 rotate together via the ball 143.

  As shown in FIGS. 32 and 33, the coil spring 145 is disposed outside the rotation transmission shaft 155 and parallel to the long axis direction of the spindle 150. One end of the coil spring 145 contacts the drive gear 425, and the other end of the coil spring 145 contacts the spindle 150. As a result, the spindle 150 is biased toward the side on which the tool bit 119 is mounted (front of the screw driver 400). A stopper 146 is disposed in front of the flange portion 154. Accordingly, the contact of the flange portion 154 and the stopper 146 restricts the movement of the spindle 150 forward of the screw driver 400. On the other hand, the drive gear 425 is urged by the coil spring 145 toward the side opposite to the side on which the tool bit 119 is mounted (rear side of the screw driver 400). At this time, the drive gear 425 is restricted from moving backward by the screw driver 400 by the retainer 430 and the needle bearing 137.

  As shown in FIG. 38, the first roller 441a and the second roller 441b are located in the central region of each side of the regular hexagon of the transmitted member 424 in a state where the rotation of the drive gear 425 is not transmitted to the transmitted member 442. . At this time, the second roller holding portion 436b is positioned to face the central region of each side of the regular hexagon of the transmitted member 424. On the other hand, the first roller holding portion 436a is located closer to the rear in the A direction, which is the rotation direction during the screw tightening operation, with respect to the central region of each side of the regular hexagon of the transmitted member 424.

(Screw tightening work)
As shown in FIG. 39, when the tool bit 119 is pressed against a screw (not shown), the spindle 150 moves rearward of the screw driver 400 against the urging force of the coil spring 145. As the spindle 150 moves, the ball 143 moves backward. Thereby, as shown in FIGS. 40 to 42, the contact between the ball 143 and the inclined portion 434 is released, and the bottom wall 427 of the drive gear 425 pressed by the flange portion 154 of the spindle 150 rotates the retainer 430. . That is, the retainer 430 is rotated in the direction indicated by the arrow A (direction A) by the frictional force between the bottom wall 427 and the retainer 430.

  The second roller 441 b is moved by the rotation of the retainer 430, and the second roller 441 b is sandwiched between the drive gear 425 and the transmitted member 442. As a result, the drive gear 425 and the transmitted member 442 rotate together in the A direction by the wedge effect of the second roller 441b. As a result, the tool bit 119 held on the spindle 150 rotates and the screw tightening operation is performed.

  When the spindle 150 moves toward the front of the screw driver 400 by screwing the screw into the workpiece, the ball 143 presses the inclined portion 434 as in the first embodiment. As a result, the retainer 430 rotates relative to the B direction with respect to the drive gear 425 rotating in the A direction. As a result, the retainer 430 and the second roller 441b move to the positions shown in FIG. 38, and the rotation transmission of the drive gear 425 to the transmission target member 442 is blocked. As a result, the screw is screwed into the workpiece to a predetermined depth, and the screw tightening operation is completed. This 2nd roller 441b is the implementation structural example corresponding to the "1st group transmission element" in this invention. The inclined portion 434 of the groove 432 is an implementation configuration example corresponding to the “guidance portion” in the present invention.

(Screw removal work)
In the fourth embodiment, similar to the first embodiment, the screwdriver 400 drives the motor 110 with the tool bit 119 without pressing the tool bit 119 in the screw removal operation.

  Specifically, in the state shown in FIG. 38, when the output shaft 111 of the motor 110 is rotated in the reverse direction, the first roller 441a sandwiched between the drive gear 425 and the needle bearing 137 by the urging force of the coil spring 145. As shown in FIG. 43, the drive gear 425 side moves. That is, as shown in FIG. 44, the first roller 441a is inclined in the first roller holding portion 436a. Accordingly, the drive gear 425 side of the first roller 441a is sandwiched between the drive gear 425 and the transmitted member 442. As a result, the drive gear 425 and the transmitted member 442 rotate together in the B direction due to the wedge effect of the first roller 441a. As a result, the tool bit 119 is driven without pressing the tool bit 119 against the screw. The first roller 441a is not limited to being sandwiched with an inclination as shown in FIG. That is, before the drive gear 425 side of the first roller 441a is clamped, the needle bearing 137 side moves, and the first roller 441a is arranged in parallel with the long axis direction of the tool bit 119 to drive the drive gear 425 and the transmitted member 442. It may be configured to be sandwiched between the two. This 1st roller 441a is the implementation structural example corresponding to the "2nd group transmission element" in this invention.

  According to the first to fourth embodiments described above, the rollers 141, 441 are switched between the rotation transmission position and the non-rotatable position by the rotation of the retainers 130, 230, 330, 430 in the circumferential direction of the spindle 150. . That is, the positions of the rollers 141 and 441 are rationally switched by the rotation of the drive gears 125, 225, 325, and 425.

  Further, according to the first to fourth embodiments, the rollers 141 and 441 are used to be sandwiched between the drive gears 125, 225, 325, and 425 and the transmitted members 142, 242, 342, and 442. The rotation of the output shaft 111 of the motor 110 is transmitted to the spindle 150 by the wedge effect of the rollers 141 and 441.

  Further, according to the first, second, and fourth embodiments, the inclined portions 134, 234 of the grooves 132, 232, 432 formed in the retainers 130, 230, 430 in accordance with the movement of the screws in the screw tightening operation. , 434 and the ball 143 come into contact, the transmission of the rotation of the drive gears 125, 225, 425 to the members 142, 242, 442 to be transmitted is blocked. As a result, the screw tightening operation is accurately completed at a predetermined screw-in depth.

  Further, according to the third embodiment, the drive with respect to the transmitted member 342 is caused by the contact between the inclined portion 334 and the convex portion 343 of the groove 332 formed in the retainer 330 as the screw moves in the screw tightening operation. Transmission of rotation of the gear 325 is interrupted. As a result, the screw tightening operation is accurately completed at a predetermined screw-in depth. Further, since the retainer 330 is rotated by the convex portion 343 provided on the transmitted member 342, it is not necessary to provide another member other than the transmitted member 342 for rotating the retainer 330 in accordance with the movement of the screw. .

  In the above embodiment, the drive gears 125, 225, 325, and 425 have a circular cross section, and the members to be transmitted 142, 242, 342, and 442 have a regular hexagonal cross section. For example, the drive gear may have a regular hexagonal cross section and the transmitted member may have a circular cross section. In addition, although one of the components of the drive gear and the transmitted member has a regular hexagonal cross section, the present invention is not limited to this, and may have a regular polygonal cross section. In this case, it is preferable that the rollers are arranged according to the number of sides of the polygon.

In view of the gist of the present invention, the following modes can be configured for the work tool according to the present invention.
(Aspect 1)
The work tool according to claim 2,
When the output shaft rotates in a predetermined first direction,
A work tool configured to mechanically restrict the relative movement of the switching member in the circumferential direction when the driven member is located at the first position.
(Aspect 2)
The work tool according to claim 7,
A biasing member for biasing the axial movement element;
The work tool characterized in that the axial movement element is configured to regulate the relative movement of the switching member in the circumferential direction by a biasing force of the biasing member.
(Aspect 3)
The work tool according to any one of claims 4 to 7,
The work tool is configured as a screw tightening tool in which a tip tool rotates a screw to perform a screw tightening operation on a workpiece,
It has a workpiece contact portion that can contact the workpiece during screw tightening work,
In the state where the workpiece contact portion is in contact with the workpiece, the tip tool screws the screw into the workpiece, so that the tip tool moves in the axial direction of the driven member, and the tip tool The amount of protrusion with respect to the tool body is configured to be large,
As the driven member moves in the axial direction during the screw tightening operation, the axial moving element moves in the axial direction, so that the axial moving element moves the switching member in the circumferential direction. The switching tool is configured to switch the transmission member from the transmission position to the non-transmission position.

(Correspondence between each component of this embodiment and each component of the present invention)
The correspondence between each component of the present embodiment and each component of the present invention is shown as follows. In addition, this embodiment shows an example of the form for implementing this invention, and this invention is not limited to the structure of this embodiment.
Screw driver 100, 200, 300, 400 is an example of composition corresponding to a "work tool" of the present invention.
The motor 110 is an example of a configuration corresponding to the “motor” of the present invention.
The output shaft 111 is an example of a configuration corresponding to the “output shaft” of the present invention.
The drive mechanisms 120, 220, 320, 420 are an example of a configuration corresponding to the “rotation transmission mechanism” of the present invention.
The drive gears 125, 225, 325, 425 are an example of a configuration corresponding to the “drive member” of the present invention.
The spindle 150 is an example of a configuration corresponding to the “driven member” of the present invention.
The rollers 141, 441a, 441b are an example of a configuration corresponding to the “transmission member” of the present invention.
The rollers 141, 441a, 441b are an example of a configuration corresponding to the “transmission element” of the present invention.
The retainers 130, 230, 330, and 430 are an example of a configuration corresponding to the “switching member” of the present invention.
The ball 143 is an example of a configuration corresponding to the “axially moving element” of the present invention.
The ball 143 is an example of a configuration corresponding to the “contact portion” of the present invention.
The convex portion 343 is an example of a configuration corresponding to the “axially moving element” of the present invention.
The convex portion 343 is an example of a configuration corresponding to the “contact portion” of the present invention.
The grooves 132, 232, 332, and 432 are an example of a configuration corresponding to the “guidance part” of the present invention.
The locator 105 is an example of a configuration corresponding to the “workpiece contact portion” of the present invention.

DESCRIPTION OF SYMBOLS 100 Screwdriver 101 Main body part 103 Main body housing 105 Locator 107 Handle 107a Trigger 107b Changeover switch 110 Motor 111 Output shaft 112 Gear tooth 119 Tool bit 120 Drive mechanism 125 Drive gear 126 Side wall 126a Gear tooth 127 Bottom wall 127a Contact part 128 Bearing 130 Retainer 131 Base 132 Groove 133 Flat portion 134 Inclined portion 135 Vertical portion 136 Side portion 137 Needle bearing 140 Rotation transmission mechanism 141 Roller 142 Transferred member 142a Ball holding groove 142b Movement restricting portion 143 Ball 145 Coil spring 150 Spindle 151 Bit holding portion 152 Bit holding ball 153 Leaf spring 154 Flange portion 155 Rotation transmission shaft 156 Ball holding groove 200 Screw dry 220 Drive mechanism 225 Drive gear 226 Side wall 226a Gear tooth 227 Bottom wall 227a Contact portion 229 Stopper 230 Retainer 231 Base portion 232 Groove 234 Inclined portion 236 Side portion 240 Rotation transmission mechanism 242 Transmitted member 242a Ball holding groove 300 Screw driver 320 Drive mechanism 325 Drive gear 326 Side wall 326a Gear tooth 327 Bottom wall 327a Abutting portion 329 Stopper 330 Retainer 331 Base portion 332 Groove 334 Inclined portion 336 Side portion 340 Rotating transmission mechanism 342 Transmitted member 343 Protruding portion 400 Screw driver 420 Driving mechanism 425 Driving gear 426 Side wall 426a Gear tooth 427 Bottom wall 427a Abutting portion 430 Retainer 431 Base 432 Groove 434 Inclined portion 435 Side portion 435a Wide portion 435b Narrow portion 436a First roller holding portion 436b Second roller Lifting portion 440 rotation transmitting mechanism 441a first roller 441b second roller 442 transmitted member 442a ball holding groove 442b movement restricting portion

Claims (12)

A work tool that rotationally drives the tip tool,
A motor having an output shaft;
A rotation transmission mechanism for transmitting the rotation of the output shaft to a tip tool,
The rotation transmission mechanism is
A drive member having a rotating shaft and rotated by the motor;
A driven member disposed coaxially with the rotating shaft and connected to a tip tool;
A drive position that is interposed between the drive member and the driven member and that transmits the rotation of the drive member to the driven member with respect to a circumferential direction of the rotation shaft, and is different from the transfer position, A transmission member capable of moving between non-transmissible positions where the rotation of the member cannot be transmitted to the driven member;
A switching member configured to switch the transmission member between the transmission position and the non-transmission position by moving relative to the driven member with respect to the circumferential direction;
The driven member is configured to be movable between a first position and a second position with respect to an axial direction in which the rotation shaft extends.
The transmission member is switched between the transmission position and the non-transmission position by allowing the relative movement of the switching member in the circumferential direction based on the position of the driven member in the axial direction. A work tool characterized by being configured as described above. The work tool according to claim 1,
When the tip tool is pressed against the workpiece, the driven member is configured to move from the first position to the second position;
When the output shaft rotates in a predetermined first direction,
When the driven member is positioned at the first position, the relative movement of the switching member in the circumferential direction is restricted, and the switching member holds the transmission member at the non-transmittable position. Has been
When the driven member is moved from the first position to the second position, the relative movement of the switching member in the circumferential direction is allowed, and the switching member moves the transmission member to the transmission position. The work tool is configured so that the rotation of the output shaft in the first direction is transmitted to the driven member via the transmission member by switching to the above. The work tool according to claim 2,
When the output shaft rotates in a second direction opposite to the first direction,
When the driven member is located at the first position, the relative movement of the switching member in the circumferential direction is allowed, and the switching member switches the transmission member to the transmission position, whereby the output A work tool configured to transmit rotation of the shaft in the second direction to the driven member via the transmission member. The work tool according to any one of claims 1 to 3,
Along with the movement of the driven member with respect to the axial direction, it has an axial movement element that moves in the axial direction,
The work tool configured to move the switching member in the circumferential direction by moving the axial movement element in the axial direction. The work tool according to claim 4,
The work tool characterized in that the axial movement element is formed integrally with the driven member. The work tool according to claim 4,
The work tool characterized in that the axial movement element is a spherical member formed separately from the driven member. The work tool according to any one of claims 4 to 6,
The axial movement element is configured to restrict the relative movement of the switching member with respect to the circumferential direction at all times,
When the driven member is moved from the first position to the second position, the axial movement element moves in the axial direction to allow the relative movement of the switching member in the circumferential direction. Is configured as
The switching member is configured to switch the transmission member from the non-transmission position to the transmission position by rotating the drive member in a state where the relative movement of the switching member is allowed. A featured work tool. The work tool according to any one of claims 4 to 7,
The work tool is configured as a screw tightening tool in which a tip tool rotates a screw to perform a screw tightening operation on a workpiece,
It has a workpiece contact portion that can contact the workpiece during screw tightening work,
With the workpiece contact portion in contact with the workpiece, the tip tool screws the screw into the workpiece, so that the driven member connected to the tip tool becomes the workpiece with respect to the axial direction. Configured to move closer,
As the driven member moves in the axial direction during the screw tightening operation, the axial moving element moves in the axial direction, so that the axial moving element moves the switching member in the circumferential direction. The switching tool is configured to switch the transmission member from the transmission position to the non-transmission position. The work tool according to claim 8,
One component of the axial direction moving element and the switching member has a guiding portion extending in the circumferential direction,
The other component of the axial direction moving element and the switching member has a contact portion that can contact the guide portion,
During the screwing operation, the switching member is moved in the circumferential direction by moving the axial movement element so as to approach the workpiece with respect to the axial direction in a state where the guide portion and the contact portion are in contact with each other. Configured to move,
The work tool configured to switch the transmission member from the transmission position to the non-transmission position by moving the switching member in the circumferential direction. The work tool according to any one of claims 1 to 9,
A portion of the driving member and the driven member that faces the other member of one member is formed in a cylindrical shape, and a portion of the other member that faces the one member is formed in a polygonal column shape. And
The transmission member is constituted by a plurality of transmission elements arranged corresponding to respective surfaces of a polygonal column. The work tool according to claim 10,
The driven member is disposed inside the driving member;
The inside of the drive member is formed in a cylindrical shape,
The outside of the driven member is formed in a polygonal column shape,
The transmission element is formed in a roller shape, and is arranged corresponding to each surface of a polygonal column formed on the driven member. The work tool according to claim 10 or 11,
When the output shaft rotates in the first direction, an operator presses the tip tool against the workpiece, so that the transmission elements of the first group among the plurality of the transmission elements are transmitted. It is configured to be switched from the impossible position to the transmission position,
When the output shaft rotates in the second direction, a state where the transmission element of the first group is held at the non-transmittable position without an operator pressing the tip tool toward the workpiece Thus, the work tool is configured such that the transmission elements of the second group other than the transmission elements of the first group are switched from the transmission impossible position to the transmission position.

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