JP6514497B2 - Shaft coupling, damper device, impact torque reduction device and component fastening machine - Google Patents

Description

  The present invention relates to a shaft coupling, a damper device, an impact torque reduction device, and a component fastening machine for increasing or decreasing a braking force to the rotation when the other member rotates relative to one member. It is.

  Conventionally, in a shaft coupling to which an input shaft and an output shaft constituting a rotation transmission system are connected, and in a damper device used for a sliding door and an open / close lid, the relative rotation of the two members occurs when the two members relatively rotate. It is sometimes used for the purpose of giving a braking force to a motion to brake its rotation or giving a heavy feeling to the rotation. In such a case, a mechanism according to each purpose is adopted in the shaft coupling and the damper device. As an example of this kind of shaft coupling, there is a shaft coupling shown in Patent Document 1. As shown in FIG. 28 (a), this shaft coupling 101 has an input shaft 103 connected with a rotating shaft 102 that rotates with the backrest (not shown) of the seat of the automobile, and a headrest (not shown) of the seat. And a pivoting lever portion 105 provided with a pivoting lever 104 for operating the motor. The pivoting lever portion 105 has a flanged cylinder (hereinafter referred to as a cylinder) 106 integrally fixed to the pivoting lever 104. Inside the cylinder 106, moving force applying means that rotates integrally with the input shaft 103. 107 are arranged. The moving force applying means 107 has a sawtooth portion 107a radially extending from the center, and transmits rotation to the driven means 108 having an inverse sawtooth portion 108a meshing with the sawtooth portion 107a via the sawtooth portion 107a. Is configured as.

  The pivot lever 104 is provided with a guide wall 104 a located inside the cylinder 106 and having a side surface extending in parallel with the axis of the input shaft 103. A projection wall 108b provided on the driven means 108 is engaged with the side surface of the guide wall 104a, and the driven means 108 can slide along the axis of the input shaft 103 and the rotating lever 104 and the cylinder 106. It is configured to be rotatable with it.

  The driven means 108 is a valve portion inside the cylinder 106 and is biased toward the moving force applying means 107 by the first spring 109 and the viscous fluid filled in the cylinder 106. Further, the driven means 108 has a conical portion 108c protruding toward the orifice 110 described later in the vicinity of the center thereof, and two ports 110a and 110a arranged at positions sandwiching the conical portion 108c. The flange portion of the orifice 110 made of a resin material is inserted into the port 110 a while securing a passage for the viscous fluid filled in the cylinder 106. The orifice 110 is biased in a direction away from the driven means 108 by the second spring 111, and the collar portion thereof is configured to be locked to the driven means 108.

  The orifice 110 has a frusto-conical main port 110b corresponding to the conical portion 108c of the driven means 108, and the main port 110b and the port 110a secure a passage through which viscous fluid flows. ing. The orifice 110 is moved toward the conical portion 108c of the driven means 108 by pressure change of the viscous fluid filled in the cylinder 106, and the main port 110b is substantially closed by the conical portion 108c. ing.

  In the shaft coupling 101 of this rotation transmission system, when the input shaft 103 rotates gently, the moving force applying means 107 gently rotates while moving the driven means 108 against the first spring 109 by the sawtooth portion 107a. start. Since the driven means 108 is moved slowly by the gentle rotation of the moving force applying means 107, the pressure inside the cylinder 106 does not increase, and the main port 110b of the orifice 110 does not narrow. Therefore, the moving force applying means 107 does not receive a large braking force from the driven means 108, and the sawtooth portion 107a can get over the reverse sawtooth portion 108a of the driven means 108. As a result, the moving force applying means 107 is independently rotated, and the rotation is not transmitted to the driven means 108 and the rotating lever 104 integral therewith. In addition, when the rotary shaft 102 and the input shaft 103 receive an abrupt rotational force as well as the backrest of the seat due to an impact from the rear of the automobile, the relative rotation of the sawtooth portion 107a of the moving force application means 107 causes the driven means 108 to It moves sharply against the first spring 109. The sudden movement of the driven means 108 causes the pressure inside the cylinder 106 to increase momentarily, and the orifice 110 moves toward the driven means 108 against the second spring 111. Therefore, the main port 110b narrows and the pressure inside the cylinder 106 further increases, so the driven means 108 is pressed to the moving force applying means 107 side, and the moving force applying means 107 receives a large braking force. As a result, the sawtooth portion 107a of the moving force applying means 107 can not get over the reverse sawtooth portion 108a of the driven means 108, and the moving force applying means 107 and the driven means 108 integrally rotate. With the rotation of the driven means 108, the rotation lever 104 can be integrally rotated to transmit the rotation to the headrest.

  Moreover, as an example of the above-mentioned damper apparatus, there exists a thing shown in FIG.28 (b). The damper device 121 is attached to a member such as an open / close door (not shown), and the input shaft 122 connected to the member and a support shaft portion 123a for rotatably guiding the input shaft 122. And a cylinder portion 123 at the center. The input shaft 122 has an impeller portion 122a at its end, and the impeller portion 122a is located inside the cylinder portion 123 and configured to receive a braking force from the viscous fluid filled in the cylinder 123. It is done. Therefore, the member to which the damper device 121 is attached can obtain a certain sense of weight during its rotation, or can be stopped with an arbitrary rotation angle by increasing the viscosity of the viscous fluid. Can.

JP, 2009-268517, A

  According to the above-described shaft joint 101 and damper device 121, when sudden rotation occurs between two members, braking is given to this rotation, and a sense of weight is given to gentle rotation between the members. The respective effects are obtained. However, although the braking force can be switched between the time when the input shaft 103 gently rotates and the time when the input shaft 103 gently rotates in the shaft coupling 101, the rotation can not have a sense of weight at the time of moderate rotation. Further, in the damper device 121, the braking force can not be switched between gentle rotation and rapid rotation only by giving a sense of weight to the rotation of the input shaft 122. Therefore, neither the shaft coupling 101 nor the damper device 121 can exhibit both of the above-described functions and effects, and each of the shaft coupling 101 and the damper device 121 can not but be a unique mechanism, and parts are shared. It is not possible to do this, and there is a problem that the number of parts in stock increases, causing the cost increase of each.

  The object of the present invention is to solve the above-mentioned problems and to provide a shaft coupling and a damper device provided with a mechanism that can be used for both a shaft coupling and a damper device, and an impact torque reducing device using the above-mentioned shaft coupling And to provide a part fastening machine.

In order to achieve the above object as a shaft coupling, the present invention is capable of rotating integrally with one of two members which are relatively pivotable with it and retractable in a direction intersecting with the center line of the pivot. A cam follower member arranged to be biased and a cam member arranged to rotate integrally with the other member, and the cam follower member is brought into contact with the cam surface of the cam member to form two members. The relative rotation between them moves the cam follower member in a direction intersecting with the center line of the rotation to increase or decrease the braking force to the rotation. According to this configuration, when relative rotation occurs between the two members, the cam follower member attached to one member moves along the cam surface of the cam member attached to the other member. Therefore, the cam follower member moves in a direction intersecting the center line of the rotation, and the braking force applied to the rotation can be increased or decreased. Not only can the rotational torque that causes the rotation be reduced and transmitted to another member, or the rotation between the two members can not be transmitted by the increase or decrease of the braking force, or the torque between the members is gentle. It is possible to give a sense of weight to such rotation. Thereby, the above-mentioned composition can be used not only as a shaft coupling of a rotation transmission system but also as a damper device arranged between two members, and parts can be shared between the shaft coupling and the damper device. The cost of each product can be reduced.

  Further, in the present invention, the cam follower member is connected to the damper portion that increases the braking force by the viscous fluid in order to urge the cam follower member to the cam member with a sufficient braking force and to sufficiently increase the braking force generated when the cam follower member is retracted. Is desirable.

  Furthermore, the present invention urges the cam follower member firmly to the cam member when the two members rotate integrally, and prevents the flow path of the viscous fluid in the damper from interfering with the cam follower member when it is retracted. It is held by the cylinder part that constitutes the damper part where the braking force increases, and this cylinder part is movably held by the member where the cam follower member is disposed, and the piston inside is locked to the piston rod fixed to the member Preferably, the piston has a port through which the viscous fluid in the cylinder portion passes.

  Moreover, the cam member is a cam follower member because the present invention quickly returns both members when the rotational torque that causes relative rotation between the two members to which the cam follower member and the cam member are respectively connected is eliminated or reduced. Preferably, it is biased by a coil spring acting in the direction of returning relative rotation between the two.

  Moreover, the present invention doubles the braking force provided by the cam follower member and maintains the rotational balance of the member on which the cam follower member is disposed, so that the cam follower member sandwiches the center line of relative rotation with the cam member. Preferably, two cam members are provided at point-symmetrical positions, and a cam member is disposed for each cam follower member.

  According to the second embodiment of the present invention, the cam member has a cam surface corresponding to the forward and reverse rotation of the cam follower member, and the cam follower member is positioned in contact with the vicinity of the center of the cam surface. May be With this configuration, the relative rotation between the two members can increase the braking force against rotation in both forward and reverse directions.

According to the present invention, in order to achieve the above object as a damper device, a cam follower is disposed so as to be retractably biased in a direction intersecting with the center line of the pivot on one of the two pivoting members. And a cam member having a cam surface connected to the other member and in contact with the cam follower member, wherein the cam follower member, the member on which the cam follower is disposed , the cam member and the member on which the cam follower is disposed are integrally formed. The cam surface has a shape that causes the cam follower member to advance or retract in a direction intersecting the center line of the rotation against the resilient biasing means by relative rotation between the two members. None, which may be configured to increase or decrease the braking force for the rotation to the cam follower member. According to this damper device, when one member is fixed and the other member is rotated, the braking force for the rotation is increased, so that the user feels a sense of weight during the rotation. It is possible to obtain a sufficient braking force to hold the rotation at an arbitrary position.

According to the fourth embodiment of the present invention, a member rotating in response to the rotation of the rotational drive source and a member of the work tool rotating in response to the rotation rotate integrally with the member. A cam follower member disposed so as to be capable of retracting in a direction intersecting with the center line of rotation, and the other member being disposed so as to rotate integrally with and rotate relative to the cam follower member The cam follower member is brought into contact with the cam surface of the cam member, and the cam follower member is retracted in the direction intersecting the center line of the rotation by relative rotation between the cam member and the cam follower member. The impact torque reducing device may be configured to increase the braking force to the rotation. In this case, when a sudden overload is applied to the work tool, this becomes an impact torque and relative rotation occurs between the cam member and the cam follower member. At this time, the cam follower member rotates while following the cam surface of the cam member, and retracts in the direction intersecting the center line of the rotation. By the backward movement of the cam follower member, the pressing force is increased, and along with this, the braking force applied from the cam follower member to the cam member is increased. Since the rotation of the cam member is braked by the increased braking force, the impact torque that causes relative rotation between the cam member and the cam follower member is reduced and transmitted. Therefore, a large impact torque in the direction to apply braking is not applied to the rotational drive source, and the impact on the rotational drive source can be reduced.

According to the fifth embodiment of the present invention, a member rotating in response to the rotation of the drive shaft of the rotational drive source and a member of the work tool rotating in response to the rotation rotate together therewith. And a cam follower member which is disposed so as to be retractably biased in a direction intersecting the center line of the rotation, and the other member so as to rotate integrally with it and to rotate relative to the cam follower member The cam follower member is brought into contact with the cam surface of the cam member, and the cam follower member intersects the center line of the rotation by relative rotation between the cam member and the cam follower member. The component fastening machine may be configured to be retracted in the direction to increase the braking force to the rotation. In this case, when the head of the fastener such as a screw or bolt tightened by the tightening tool is seated on the member to be fastened, the rotational speed of the tightening tool is rapidly reduced, but the rotational speed of the rotational drive source is high As a result, a large impact torque is generated in the cam follower member that contacts the cam member that rotates integrally with the tightening tool. The impact torque causes the cam member to rotate relative to the cam follower member in the direction opposite to the tightening direction. Therefore, the cam follower member rotates while following the cam surface of the cam member, and retracts in the direction intersecting the center line of the rotation. By the backward movement of the cam follower member, the pressing force is increased, and the braking force applied to the cam follower member is increased accordingly. Since the rotation of the cam member is braked by the increased braking force, the impact torque that causes relative rotation between the cam member and the cam follower member is reduced and transmitted. Therefore, when the load current applied to the rotational drive source is detected to control the tightening torque, the impact when the head of the fastener is seated on the fastened member even if the rotational speed of the rotational drive source is increased. The torque can be reduced by the shaft coupling and transmitted to the rotational drive source, and the load current of the rotational drive source is not affected thereby, and a load current suitable for tightening torque control can be obtained. In addition, since the impact torque generated in the cam follower member that contacts the cam member that rotates integrally with the tightening tool when the screw is seated is reduced and transmitted to the rotational drive source, the impact torque below can not be controlled until now. The torque can be controlled even at small torque values, and tightening torque control can be performed at high speed and with a wide setting range.

  Further, when the component fastening machine described above completes tightening of the fastener and lifts and returns, the cam member does not lift up the member to be fastened together with the completed fastener. It is desirable that the coil spring be biased by a coil spring acting in the direction of restoring the relative rotation between the two.

  According to the present invention described above, a shaft coupling and a damper device provided with a mechanism capable of increasing / decreasing a braking force for relative rotation between two members or giving a sense of weight to the rotation. And an impact torque reduction device and a component fastening machine can be provided.

FIG. 1 is a front view of a shaft coupling according to a first embodiment of the present invention. FIG. 1 is a plan view of a shaft coupling according to a first embodiment of the present invention. The disassembled perspective view of the axial coupling which concerns on the 1st Embodiment of this invention. 2. IV-IV sectional view line | wire which abbreviate | omitted the internal structure of FIG. 2 partially. FIG. 5 is a cross-sectional view of a main part of line V-V in FIG. VI-VI sectional view taken on the line of FIG. FIG. 5 is a partial perspective view emphasizing a non-operating state (a) and an operating state (b) of the connection structure between the piston of the cylinder portion and the flange portion of the piston rod according to the first embodiment of the present invention. The VIII-VIII line principal part expanded sectional view of FIG. The IX-IX line principal part expanded sectional view of FIG. XX sectional drawing of FIG. XI-XI sectional view taken on the line of FIG. Explanatory drawing which shows the operation state of the axial coupling which concerns on the 1st Embodiment of this invention. Explanatory drawing which shows the operation state of the cylinder part of the axial coupling which concerns on the 1st Embodiment of this invention. Explanatory drawing which shows the operation state of the coiled spring of the axial coupling which concerns on the 1st Embodiment of this invention. The front view of the axial coupling which concerns on the 2nd Embodiment of this invention. 15. The XVI-XVI sectional view taken on the line of FIG. XVII-XVII sectional view taken on the line of FIG. Explanatory drawing which shows the operation state of the axial coupling which concerns on the 2nd Embodiment of this invention. The principal part explanatory drawing which shows the attachment state of the damper apparatus which concerns on the 3rd Embodiment of this invention. The XX-XX line expanded sectional view of FIG. The principal part front view which notched a part of impact torque reduction device concerning a 4th embodiment of the present invention. The principal part explanatory view showing the operation state of the impact torque reduction device concerning a 4th embodiment of the present invention. The principal part front view of the components fastening machine which concerns on the 5th Embodiment of this invention. Explanatory drawing which partially abbreviate | omitted the tightening start state of the components fastener which concerns on the 5th Embodiment of this invention. Explanatory drawing which partially abbreviate | omitted the screw seating state of the component fastener which concerns on the 5th Embodiment of this invention. The wave form diagram which shows the relation between the load current at the time of tightening of the parts fastening machine concerning the 5th embodiment of the present invention-tightening time. The wave form diagram which shows the general load current-clamping time relationship of a parts fastening machine. Explanatory drawing which shows the conventional example of each of a shaft coupling and a damper apparatus.

  First Embodiment

  Hereinafter, a shaft joint according to a first embodiment of the present invention will be described based on the drawings. As shown in FIGS. 1 to 6, the shaft coupling 1 is a drive shaft 2 of a rotational drive source (not shown) as an example of a drive side member of a rotation transmission system and a transmission shaft (not shown) of an example of a driven side member. And an input shaft 3 having an engagement hole 3a in which the drive shaft 2 is fitted, and an output shaft 4 to which the transmission shaft is connected. The input shaft 3 has, at one end, a substantially rectangular connecting flange 3b, and to the connecting flange 3b, a substantially cylindrical expanded diameter shaft 5 is fixed so as to rotate integrally. The enlarged diameter shaft portion 5 has defect portions 5a, 5a at point-symmetrical positions, and is attached to the defect portions 5a, 5a such that a part of the cam follower member 6 is exposed. Further, a support shaft hole 5b is provided at the center of the lower surface of the enlarged diameter shaft portion 5 and a support shaft 18c embedded in the output shaft 4 is provided in the support shaft hole 5b. The expanded diameter shaft portion 5 is rotatably guided by the support shaft 18c.

  In the expanded diameter shaft 5, two guide holes 5c, 5c are provided so as to face the defect 5a, 5a and extend in a direction crossing the axis of the input shaft 3 and the axis. In the guide holes 5c, 5c, two cam follower members 6, 6 are disposed so as to be rectilinear and reciprocatively movable and point symmetrical with respect to the axis of the input shaft 3, respectively. By this arrangement, the rotational balance of the input shaft 3 is maintained. The cam follower member 6 includes a roller 7 and a cylinder main body 9 of a cylinder portion 8 provided with a roller attaching portion 9a for rotatably holding the roller. The cylinder portion 8 serves as a cam for the cam portion 18b. It comprises a damper portion which functions as a damper while acting as a resilient biasing means pressing against the surface 18d. Further, the pressing force of the cylinder portion 8 applies a braking force to the cam portion 18b to the roller 7. The braking force causes the roller 7 and the cam portion 18b, that is, the input shaft 3 and the output shaft 4 to rotate integrally. Is configured as.

  The cylinder body 9 has a cylinder chamber 9b therein, and a piston 10 for dividing the cylinder chamber 9b into a first chamber 9b1 and a second chamber 9b2, and a flange portion to which the piston 10 is locked A piston rod 11 having one end 11a is disposed. A cylinder lid 12 for closing the cylinder chamber 9b is attached to the cylinder body 9. The piston rod 11 penetrates the cylinder lid 12 and one end thereof is a guide hole 5c of the enlarged diameter shaft 5 It is fixed to the fixing pin 13 which crosses. As a result, the cylinder lid 12 can slide along the piston rod 11 while maintaining the sealing effect as the cylinder body 9 moves.

  The piston 10 is provided with a stepped hole 10a in which the first chamber 9b1 side of the cylinder chamber 9b is a circular hole and the second chamber 9b2 is a non-circular hole as shown in FIGS. The stepped portion 10 b formed in the piston 10 can be in contact with the flange portion 11 a of the piston rod 11 by the stepped hole 10 a. Further, the flange portion 11a of the piston rod 11 is formed in a substantially rectangular shape in which two disc-like opposing portions are made smaller, and two opposing portions in a direction orthogonal to the two portions are largely cut off. The flange portion 11a is configured to communicate with the non-circular hole portion of the stepped hole 10a only at two places of the small cut-off portion when contacting the step portion 10b of the piston 10 as the first port 10c. ing. Further, the flange portion 11a of the piston rod 11 has pin locking holes 11b at two opposing corners, and one of the locking pins 14 pressed into the piston 10 is inserted into the locking pin hole 11b. The part is positioned with a slight gap between the collar part 11a. This allows the piston 10 to be slightly separated from the flange portion 11 a of the piston rod 11.

  The piston rod 11 has a bottomed hole 11c bored along its axis, and one end of a pilot rod 15 is inserted into the bottomed hole 11c. The pilot rod 15 is resiliently biased by a spring 16 disposed in the bottomed hole 11 c, and the other end is in contact with the bottom of the cylinder body 9. As a result, the cylinder body 9 is always urged toward the roller 7 with the pressure of the viscous fluid in the cylinder chamber 9b, so the piston 10 slightly moves relative to the piston rod 11, and the flange portion 11a of the piston rod 11 It is located slightly away from the step 10b of the piston 10 (see FIG. 7A). At this time, the large cut-off portion of the flange portion 11a becomes a second port 10d communicating with the non-circular hole portion of the stepped hole 10a through the gap generated between the step portion 10b and the flange portion 11a. The first chamber 9b1 and the second chamber 9b2 of the cylinder chamber 9b of the cylinder body 9 are filled with the viscous fluid, and the viscous fluid is transferred to the first port 10c or the first port 10c as the cylinder body 9 moves. Since the cylinder body 9 moves past the second port 10d, the cylinder body 9 can move more quickly at the time of forward movement than at the time of backward movement. Further, since the viscous fluid changes the passing speed of the above-mentioned first port 10c according to its viscosity, it is possible to set the braking force generated when the cylinder body 9 retracts to an arbitrary size by adjusting this viscosity. it can.

  The output shaft 4 of the shaft coupling 1 has a connecting portion 17 extending to a position where the transmission shaft is connected as shown in FIGS. 3 to 5 and a disc-like enlarged end portion 18a located on the input shaft 3 side. And a cam member 18 provided with a cam portion 18b integrally formed therewith. A support shaft 18c is implanted at the center position of the enlarged diameter end 18a, and the support shaft 18c is provided in a support shaft hole 5b provided on the lower surface of the expanded diameter shaft 5 of the input shaft 3. When positioned, the bulging shaft portion 5 integral with the input shaft 3 is rotatably guided. Further, two cam portions 18 b are disposed at positions surrounding and facing a part of the expanded diameter shaft portion 5. The cam portions 18b and 18b each have a cam surface 18d formed by a circular arc having a point-symmetrical shape with respect to the axis of the output shaft 4, and the circular arc is output toward the normal rotation direction shown in FIG. It is shaped to gradually approach the axis of the shaft 4. The roller 7 of the cam follower member 6 held by the input shaft 3 is in contact with the cam surface 18d of the cam portion 18b, and the braking force applied from the roller 7 to the cam portion 18b by the pressing force of the cylinder portion 8 The cam portion 18 b and the roller 7, that is, the output shaft 4 and the input shaft 3 are integrally rotatable.

  A guide groove 18e extending in an arc along the outer periphery of the cam 18 is opposed to the guide groove 18e, and the guide groove 18e is provided with an expansion shaft 5 of the input shaft 3 respectively. A guide pin 5d implanted so as to extend parallel to the axis is engaged in the vicinity of the outer periphery of. By the engagement between the guide groove 18e and the guide pin 5d, the rotation angle of the output shaft 4 relative to the input shaft 3, that is, the phase difference between the two shafts is restricted.

  In the two cams 18b and 18b of the cam member 18, as shown in FIGS. 3, 4, 10 and 11, the bearing plate 19 is used for connecting the flange 3b of the input shaft 3 and the enlarged diameter shaft. The input shaft 3 is rotatably guided by the bearing plate 19 so that relative rotation between the input shaft 3 and the output shaft 4 is guided. Further, on the inner surface of the bearing plate 19, two spring locking blocks 20, 20 are attached at point-symmetrical positions with respect to the center position, and the expanded diameter shaft portion 5 via a spring mounting pin 5e. One end of the coil spring 5 f attached is locked. The spring mounting pin 5e is positioned in the through groove 3c provided in the connecting collar 3b, and the other end of the coil spring 5f is positioned in the through groove 3c and locked to the connecting collar 3b. There is. Thus, the coil spring 5 f acts in the direction to restore the relative rotation between the bearing plate 19 and the expanded diameter shaft portion 5, so that the relative rotation between the input shaft 3 and the output shaft 4 is achieved. Even if a phase difference occurs between the two axes, the phase difference between the two axes can be quickly eliminated.

  When the input shaft 3 receives the rotation of the drive shaft 2 of the rotational drive source and rotates in the forward direction as shown in FIGS. 4 and 13 (a) in the above shaft coupling, the bulging shaft is integrated with the input shaft 3. The portion 5 and the cam follower member 6 held thereby rotate around the axis of the input shaft 3. With the rotation of the cam follower member 6, the cam member 18 having the cam portion 18b is integrally rotated by the braking force applied to the roller 7 of the cam follower member 6, and the output shaft 4 is integrally rotated with the cam member 18 in the forward direction. Can be rotated.

  When the load on the driven side increases while the rotation of the transmission shaft and the output shaft 4 decreases while the input shaft 3 and the output shaft 4 rotate integrally, the rotation of the input shaft 3 in the braking direction is applied. Torque is generated. When the rotational force due to this rotational torque becomes larger than the braking force between the cam portion 18 b of the cam member 18 and the roller 7 of the cam follower member 6, relative rotation occurs between the input shaft 3 and the output shaft 4. Turns with respect to the input shaft 3, and a phase difference occurs between the two shafts. At this time, since the cam portion 18b of the cam member 18 is rotated by the rotation, the roller 7 of the cam follower member 6 moves relatively while following the cam surface 18d of the cam portion 18b. As a result, while the roller 7 and the cylinder main body 9 of the cylinder portion 8 holding the same relatively retract the pilot rod 15 elastically urged in the piston rod 11, the inside of the guide hole 5c of the enlarged diameter shaft portion 5 Is retracted in the direction intersecting the axis of the input shaft 3.

  Immediately after the start of retraction of the cylinder body 9, the viscous fluid filled in the second chamber 9b2 of the cylinder chamber 9b is pushed out from the first port 10c and the second port 10d to the first chamber 9b1 of the cylinder chamber 9b. 9 begins to retreat smoothly. When the cylinder body 9 retracts thereafter, the piston 10 moves until it abuts on the flange portion 11a of the piston rod 11 with the pressure increase of the viscous fluid in the second chamber 9b2, and the second port 10d is closed (FIG. 7) (B)). As a result, a part of the viscous fluid left in the second chamber 9b2 is pushed out only from the first port 10c provided in the piston 10 to the first chamber 9b1 of the cylinder chamber 9b, and the cylinder portion 8 functions as a damper . At the same time, since the remaining viscous fluid in the second chamber 9b2 is once compressed and rises while the cylinder body 9 retracts (see FIGS. 12 and 13 (b)), the pressing force applied to the cylinder body 9 is increased. The braking force applied from the roller 7 to the cam portion 18b and the cam member 18 is increased. Since the increased braking force is applied to relative rotation between the input shaft 3 and the output shaft 4, the rotation is braked, and the rotational torque that causes the rotation is reduced. Is transmitted to the input shaft 3. As a result, even if the rotational speed of the output shaft 4 drops sharply and a rotational torque that applies braking to the rotation of the input shaft 3 is generated, this rotational torque is reduced without being transmitted to the input shaft 3 as it is. Since it is transmitted to 3, there is no adverse effect on the rotational drive source. Also, when the relative rotation occurs gently between the input shaft 3 and the output shaft 4, the relative rotation can be given a sense of weight, so as a damper device for the opening and closing door of various devices Can be used, and the parts of the shaft coupling and the damper device can be made common, and the respective costs can be reduced.

  Further, as the relative rotation occurs between the input shaft 3 and the output shaft 4 and a phase difference is caused between the two shafts, between the bearing plate 19 and the enlarged diameter shaft portion 5 which rotates integrally with each other. Also, as shown in FIG. 14 (a), a phase difference occurs, and the coil spring 5f held by the expanded diameter shaft 5 is flexed to increase its elastic force. Therefore, when the rotational torque causing relative rotation between the input shaft 3 and the output shaft 4 is eliminated or reduced, the phase difference between the expanded diameter shaft 5 and the bearing plate 19 is obtained by the action of the elastic force of the coil spring 5f. Will disappear. As a result, as shown in FIG. 14B, the cam member 18 integral with the bearing plate 19 returns to the roller 7 of the cam follower member 6 so as to have the positional relationship before the rotation. At this time, a delay occurs when the cylinder main body 9 of the cylinder portion 8 located at the position shown in FIG. 13B returns to the position shown in FIG. 13A, so the roller 7 may once leave the cam surface 18d. it can. Thereafter, the roller 7 and the cylinder main body 9 holding the same also return to the position before the rotation described above, and the cam member 18 and the roller 7, that is, the input shaft 3 and the output shaft The rotation of the input shaft 3 can be transmitted to the output shaft 4.

Although not shown, the resilient biasing means may be only a spring for applying a braking force to the roller 7, or the input shaft 3 and the output shaft 4 are on the drive side and the driven side are reversed. You may use it. Although not shown, when the input shaft 3 and the output shaft 4 rotate integrally, the contact position between the cam surface 18 d of the cam portion 18 b of the cam member 18 and the roller 7 of the cam follower member 6 The cam surface 18d may be located near the four axis. In this case, when relative rotation occurs between the input shaft 3 and the output shaft 4, the braking force on the cam surface 18d of the roller 7 is reduced, so that the rotation of the input shaft 3 is not transmitted to the output shaft 4. can do.
Second Embodiment

  A shaft joint according to a second embodiment of the present invention will be described based on the drawings. This shaft coupling 1A can cope with relative rotation in both forward and reverse directions as shown in FIGS. 15 to 17. The shaft coupling 1 according to the first embodiment is the enlarged diameter shaft 5 And the structure of the cam member 18 is different, so the detailed description of the same portions will be omitted, and the structure of the enlarged diameter shaft 5A of the shaft joint 1A and the cam member 18A will be mainly described (note: The same reference numerals are used for the same parts as those of the shaft coupling 1 according to the first embodiment. The shaft coupling 1A includes an input shaft 3 having an engagement hole 3a to which a member disposed on the drive side of a rotation transmission system is coupled, an enlarged diameter shaft portion 5A attached to one end thereof, and the expanded diameter shaft It has an output shaft 4A having a post cam member 18A rotatable relative to the portion 5A. The enlarged diameter shaft portion 5A has a substantially cylindrical shape, and the expanded diameter shaft portion 5A is provided with a guide hole 5cA extending in a direction crossing the axis at a position passing through the axis. In this guide hole 5cA, a cam follower member 6A having the same structure as that of the cam follower member 6 according to the first embodiment except for the roller attachment portion 9a is disposed so as to be rectilinearly reciprocatingly movable.

  The cam follower member 6A includes a roller 7 and a cylinder main body 9 of a cylinder portion 8 provided with a roller attachment portion 9aA for rotatably holding the roller. The cylinder portion 8 forms a damper portion that performs a damper function while forming a resilient biasing unit that presses the roller 7 so as to abut the cam surface 18dA of the cam portion 18bA. The pressing force of the cylinder portion 8 applies a braking force to the cam portion 18bA to the roller 7, and the braking force causes the roller 7 and the cam portion 18bA, that is, the input shaft 3 and the output shaft 4A to rotate integrally. It is done.

  A cam member 18A is provided at the upper end of the output shaft 4A of the shaft coupling 1A, and the cam member 18A includes a disk-like enlarged end portion 18aA and a cam portion 18bA integrally provided therewith. ing. The cam portion 18bA has a cam surface 18dA in contact with the roller 7 of the cam follower member 6A in a part thereof, and the cam surface 18dA is formed by an arc opposed to each other across the axis of the output shaft 4A. The circular arcs are located at positions separated from the axis of the output shaft 4A at their central portions, respectively, and are shaped so as to gradually approach the axis of the output shaft 4A in both forward and reverse rotational directions. The roller 7 of the cam follower member 6A is in contact with the cam surface 18dA near the central portion thereof, and the cam portion 18bA and the roller 7 are integrated by the braking force applied to the roller 7, and the input shaft 3 and the output shaft It is configured to rotate integrally with 4A. Although two cam surfaces 18dA are provided at opposing positions, they can correspond to two cam follower members (not shown) arranged in two upper and lower stages in consideration of the rotational balance of the input shaft 3. It is good also as one cam surface 18dA with respect to one cam follower member 6A.

  The cam portion 18bA of the cam member 18A has, on its outer surface, two notched windows 18fA and 18fA positioned opposite to the two cam surfaces 18dA and 18dA and facing each other. The notch window 18fA has a size such that the cam follower member 6A held by the enlarged diameter shaft portion 5A of the input shaft 3 is exposed, and the cam follower member 6A is configured to be easily replaced.

In the above shaft joint, a rotational torque causing relative rotation in the forward or reverse direction is applied between the input shaft 3 and the output shaft 4A, and the rotational force by this rotational torque is the cam portion 18bA of the cam member 18A and the cam follower member When the braking force between the roller 6A and the roller 6A becomes larger, the output shaft 4A rotates in either the forward or reverse direction. The cam portion 18bA of the cam member 18A is rotated with the rotation of the output shaft 4A (see the rotation in the reverse direction shown in FIG. 18), and the roller 7 is the cam of the cam portion 18bA with the rotation. The surface 18dA is followed to move relatively (the case of rotation of the output shaft 4A in the normal direction is shown by a dashed dotted line in FIG. 18). Since the roller 7 retracts in a direction intersecting with the axis of the expanded diameter shaft 5A with this movement, the cylinder 8 temporarily increases its pressing force while performing the damper function by the retraction of the roller 7. As the pressing force of the cylinder portion 8 increases, the braking force applied to the roller 7 increases, and the rotation of the cam portion 18bA is braked by the increased braking force. The rotational direction and the reverse direction are reduced and transmitted to the input shaft 3. As a result, even if the rotational speed of the output shaft 4A drops sharply and a rotational torque that applies braking to the rotation of the input shaft 3 is generated, this rotational torque is reduced without being transmitted to the input shaft 3 as it is. Since it is transmitted to 3, there is no adverse effect on the rotational drive source.
Third Embodiment

  A damper device according to a third embodiment of the present invention will be described with reference to the drawings. The damper device is used when attaching the open / close door of various devices. This damper device 51 has the same structure as the shaft joint 1 according to the first embodiment as shown in FIGS. 19 and 20 except for the mounting structure of the input shaft 3 and the output shaft 4. The detailed description of the same parts will be omitted, and the mounting structure of the input shaft 3 and the output shaft 4 will be mainly described (in the description, the same parts as the parts of the shaft coupling 1 according to the first embodiment) , Use the same number). The damper device 51 is used to attach the open / close door 53 to the device body 52, and the open / close door 53 is rotatably held by the lower fixing tool (not shown) of the device body 52. , A mounting space 53a formed in the upper corner, and a fixed shaft 54 having a quadrangular column (not shown) extending in the mounting space 53a at the top. The damper device 51 rotates relative to the input shaft 3 to which the fixed shaft 54 is connected, the expanded diameter shaft 5 attached to one end of the input shaft 3, and the expanded diameter shaft 5. And an output shaft 4 with a cam member 18, which is possible.

  Two cam follower members 6, 6 are urged backwardly in the direction intersecting with the axis of the input shaft 3 and arranged at a point-symmetrical position. The cam follower members 6 and 6 each include a roller 7 and a cylinder main body 9 of a cylinder portion 8 provided with a roller mounting portion 9a that rotatably holds the roller.

  The cylinder portion 8 is a damper portion that functions as a damper while acting as resilient biasing means for pressing the roller 7 so as to abut the cam surface 18d of the cam portion 18b described later. The pressing force of the cylinder portion 8 applies a braking force to the cam portion 18b to the roller 7, and the roller 7 and the cam portion 18b, that is, the input shaft 3 and the output shaft 4 are integrally held by the braking force.

  An upper portion of the output shaft 4 of the damper device 51 is fixed to the device main body 52 via an upper fixing tool 55, and a cam member 18 is provided at a lower portion thereof. The cam member 18b is provided with cam portions 18b, 18b which abut against the rollers 7, 7 of the cam follower members 6, 6, respectively. Thus, the cam member 18 is fixed to the device main body 52 side, and guides the rotation of the roller 7 at the fixed position. The cam portion 18b of the cam member 18 is formed with a cam surface 18d that approaches the axis of the output shaft 4 as it advances in the closing direction of the open / close door 53 at a position where the roller 7 abuts. The cam surface 18 d rotates the roller 7 as the input shaft 3 rotates with respect to the output shaft 4, that is, the roller 7 with respect to the cam portion 18 b in the closing direction of the open / close door 53. That is, it is shaped to act to retract in the direction intersecting the axis of the input shaft 3. Further, since the cam surface 18 d acts to retract the roller 7, the pressing force of the cylinder portion 8 is once increased to increase the braking force applied to the roller 7, and the space between the roller 7 and the cam portion 18 b is increased. It acts to give a sense of weight to the relative rotation of the

  The roller 7 of the cam follower member 6 abuts on the cam surface 18 near the position where the front cam surface 18 d most approaches the axis of the output shaft 4 when the open / close door 53 is in the closed state. As a result, the roller 7 is retracted and positioned in the guide hole 5c of the expanded diameter shaft portion 5, so the pressing force of the cylinder portion 8 is increased and the braking force with the cam member 18 is increased during closing of the opening / closing door. Is configured to Further, the contact position between the roller 7 and the cam surface 18 d of the cam portion 18 b is configured such that the cam surface 18 d is near the position farthest from the axis of the output shaft 4 when the open / close door 53 is in the maximum open state. It is done. Since the roller 7 is at the forward position in the guide hole 5c of the expanded diameter shaft 5 when the roller 7 is located at the above-mentioned contact position, the pressing force of the cylinder portion 8 is reduced. Although the applied braking force is also reduced, this braking force is large enough to stop the open / close door 53 in the maximum open state.

  In the damper device, when the open / close door 53 in the closed state is opened, the fixed shaft 54 integral therewith is rotated, and the input shaft 3 and the cam follower member 6 are integrally rotated accordingly. The position at which the roller 7 abuts against the cam surface 18 d of the cam portion 18 b with the rotation of the cam follower member 6 is such that the cam surface 18 d is near the farthest position from the position closest to the axis of the output shaft 4. Move to Thus, the roller 7 advances in a direction intersecting the center line of the rotation, that is, the axis of the input shaft 3. The forward movement of the roller 7 causes the cylinder portion 8 to reduce its pressing force while performing a damper function. As the pressing force of the cylinder portion 8 decreases, the braking force applied to the roller 7 decreases, and the reduced braking force is applied to the cam portion 18b. At this time, although the braking force is reduced, the braking force is maintained at a sufficient size to stop the open / close door 53 in the maximum open state. Therefore, the open / close door 53 is held in the maximum open state by this braking force (see the two-dot chain line in FIG. 20).

  When the open / close door 53 is turned to be in the closed state, the input shaft 3 is integrally rotated with the fixed shaft 54. Therefore, as the input shaft 3 is rotated, the roller 7 has the cam surface 18d of the cam portion 18b. Run up while copying Therefore, the roller 7 retracts in the guide hole 5c of the expanded diameter shaft portion 5 in the direction intersecting the axis of the input shaft 3, so the cylinder portion 8 interlocked with the roller 7 increases its pressing force while fulfilling the damper function. . As the pressing force of the cylinder portion 8 increases, the braking force applied to the roller 7 gradually increases, and becomes maximum when the open / close door 53 is closed. This maximum braking force gives a sense of weight to the rotation of the open / close door 53 when closing the open / close door 53, so that the open / close door 53 gives an impact to the device body 52 when the open / close door 53 is closed It is eliminated.

In the case where the maximum opening angle of the open / close door 53 is increased, the damper devices 51 can be disposed in a plurality of stages between the fixed shaft 54 of the open / close door 53 and the upper fixture 55. In this case, it is desirable that the output shafts 4 of the other damper devices (not shown) except for the damper device 51 fixed to the upper fixture 55 be as long as possible to be connected to the input shaft 3 of each damper device. Further, although the third embodiment described above is used without changing the structure of the shaft joint 1 according to the first embodiment, this may be changed. For example, although not shown, the output shaft 4 of the damper device 51 may be used as a structure of only the cam member 18 provided with the enlarged diameter end 18a. In this case, by fixing the cam member 18 with the upper fixing tool 55, the cam member 18 is supported so as to be covered by the upper fixing tool 55, so that the rotation of the input shaft 3 is securely protected. Furthermore, although not shown, the cam portion 18b of the cam member 18 may be extended by using one cam follower member 6 held by the input shaft 3, and the rotation angle of the cam follower member 6 may be increased. In this case, the maximum opening angle of the open / close door 53 can be made sufficiently large. Moreover, any of the input shaft 3 and the output shaft 4 of the damper device 51 described above can be mounted on the fixed side.
Fourth Embodiment

  A shock absorbing device according to a fourth embodiment of the present invention will be described based on the drawings. The shock absorbing device 61 includes a drive shaft 63a of a motor 63 of an electric circular saw 62, which is an example of a member that rotates in response to rotation of a rotational drive source as shown in FIG. The shaft coupling 1 according to the first embodiment is disposed between the two. Since this shock absorbing device 61 has the same structure as the shaft coupling 1 of the first embodiment, the detailed description of the same parts will be omitted, and between the drive shaft 63a and the input shaft 3 of the shaft coupling 1, the shaft The connection structure between the output shaft 4 of the joint 1 and the circular saw teeth 64 will be mainly described (In the description, the same parts as those of the shaft joint 1 according to the first embodiment will be denoted by the same reference numerals) . The shock absorbing device 61 has an input shaft 3 to which a drive shaft 63a of a motor 63 is connected, and an enlarged diameter shaft 5 attached to one end thereof. The two cam follower members 6, 6 are urged backwardly in the direction intersecting with the axis of the input shaft 3 and arranged at a point symmetrical position. The cam follower member 6 includes a roller 7 and a cylinder main body 9 of the cylinder portion 8 provided with a roller mounting portion 9a which rotatably holds the roller (see FIG. 6). The cylinder portion 8 is a damper portion that functions as a damper while acting as resilient biasing means for pressing the roller 7 so as to abut the cam surface 18d of the cam portion 18b described later. The pressing force of the cylinder portion 8 applies a braking force to the cam portion 18b to the roller 7. The braking force causes the roller 7 and the cam portion 18b, that is, the input shaft 3 and the output shaft 4 to rotate integrally. It is done.

  Further, the shock absorbing device 61 has an output shaft 4 to which a circular sawtooth 64 is connected at one end, and the output shaft 4 is rotatably held by a holder 66 attached to the side surface of the motor 63. A cam member 18 is provided at the other end of the output shaft 4, and the cam member 18 has two cam portions 18b and 18b with which the rollers 7 and 7 of the cam follower members 6 and 6 respectively abut. ing. The cam portion 18b is formed with a cam surface 18d that gradually approaches the axis of the output shaft 4 as it proceeds in the cutting direction (forward rotation direction) at a position where the roller 7 abuts (see FIG. 6). The cam surface 18 d rotates as the output shaft 4 rotates relative to the input shaft 3, that is, the cam member 18 rotates relative to the roller 7 in the direction opposite to the cutting direction (forward rotation direction). Is configured to act in such a way as to retract in a direction intersecting the center line of the rotation, that is, the axis of the input shaft 3. Further, since the cam surface 18 d acts to retract the roller 7, the pressing force of the cylinder portion 8 is once increased to increase the braking force applied to the roller 7 so that the relative position of the cam portion 18 b is increased. It acts to apply braking to the rotation.

  A bearing plate 19 is fixed to the two cam portions 18 b and 18 b described above, and the bearing plate 19 covers the expanded diameter shaft portion 5 of the input shaft 3 and guides the input shaft 3 rotatably. The relative rotation between the input shaft 3 and the output shaft 4 is guided.

  The input shaft 3 and the output shaft 4 are connected by the same connection structure as the shaft joint 1 described in the first embodiment, so the description of the other detailed structure is omitted.

  In the shock absorbing device, when the motor 63 rotates at a predetermined rotational speed, the rotation of the drive shaft 63 a is transmitted to the input shaft 3. When the input shaft 3 is rotated and the cam follower member 6 held by the lower diameter expanded shaft portion 5 is rotated, the braking force applied by the roller 7 at the tip to the cam portion 18b of the cam member 18 causes the output shaft 4 to be rotated. And the circular saw blade 64 can rotate together.

  In this state, as shown in FIG. 22, when the circular sawtooth 64 rotating in response to the rotation of the motor 63 is positioned at the cutting position on the mating member 65 and the circular sawtooth 64 is pressed, the mating member 65 is cut. . During this time, if the circular sawtooth 64 is suddenly overloaded, the rotational speed of the output shaft 4 having the circular sawtooth 64 at one end is rapidly reduced. At this time, as the rotational speed of the motor 63 increases, a large impact torque in the direction to apply braking to the motor 63 is generated. When the rotational force by this impact torque becomes larger than the braking force between the cam portion 18 b of the cam member 18 and the roller 7 of the cam follower member 6, the output shaft 4 moves to the input shaft 3, that is, the cam portion 18 b contacts the roller 7. On the other hand, the motor 63 is relatively rotated in the direction to apply the braking (see FIG. 12). Therefore, the roller 7 rotates while following the cam surface 18d of the cam portion 18b, and retracts in a direction intersecting the center line of the rotation, that is, the axis of the input shaft 3. By the backward movement of the roller 7, the cylinder portion 8 temporarily increases its pressing force while performing a damper function. As the pressing force of the cylinder portion 8 increases, the braking force applied from the roller 7 to the cam portion 18b increases, and the rotation of the cam portion 18b is braked by the increased braking force. The impact torque applied to the cam portion 18 b of the cam member 18 is reduced and transmitted to the input shaft 3. Therefore, a large impact torque in the direction of braking is not applied to the drive shaft 63a of the motor 63, and the impact on the motor 63 can be reduced.

Although not shown, even if the output shaft 4 is attached to the drive shaft 63a of the motor 63 of the impact absorbing device 61 described above and the input shaft 3 is attached to the circular sawtooth 64, the same effect can be obtained.
Fifth Embodiment

  A parts fastening machine according to a fifth embodiment of the present invention will be described based on the drawings. As shown in FIG. 23, the parts fastening machine 71 is an axis according to the first embodiment of the connecting shaft 75 of an example of a member that rotates in response to the rotation of a rotational drive source and a driver bit 76 of an example of a tightening tool. It is connected by a joint 1. In the component fastening machine 71, the detailed description of the shaft joint 1 is omitted, and the connection structure between the connecting shaft 75 and the input shaft 3 of the shaft joint 1, the output shaft 4 of the shaft joint 1 and the driver bit 76 is mainly described. (In the description, the same parts as those of the shaft joint 1 according to the first embodiment are denoted by the same reference numerals). The component fastening machine 71 has a driver stand 72 held up and down on a machine base (not shown), and a motor 74 of a rotational drive source is fixed to the driver stand 72 via a driver attachment 73. ing. The drive shaft (not shown) of the motor 74 is connected to the connecting shaft 75 via a reduction gear mechanism (not shown), and the tip of the connecting shaft 75 has a square pole shape, and the engagement hole 3a will be described later. Is fitted to. The driver fitting 73 rotatably guides the shaft coupling 1 therein, and the input shaft 3 of the shaft coupling 1 has an engagement hole 3a in which the tip of the connecting shaft 75 is fitted. (See Figure 4). An enlarged diameter shaft portion 5 is connected to one end of the input shaft 3, and two cam follower members 6, 6 are attached to the expanded diameter shaft portion 5 so as to be able to retract in a direction intersecting the axis of the input shaft 3. It is biased and placed in a point symmetrical position. The arrangement of the cam follower members 6, 6 maintains the rotational balance of the input shaft 3.

  The cam follower member 6 includes a roller 7 and a cylinder main body 9 of a cylinder portion 8 provided with a roller mounting portion 9a for rotatably holding the roller. The cylinder portion 8 forms a damper portion which functions as a damper while acting as resilient biasing means for pressing the roller 7 so as to abut the cam surface 18d of the cam portion 18b (see FIG. 6). Further, the pressing force of the cylinder portion 8 applies a braking force to the cam portion 18b to the roller 7. The braking force causes the roller 7 and the cam portion 18b, that is, the input shaft 3 and the output shaft 4 to rotate integrally. Is configured as.

  At the upper end of the output shaft 4 of the shaft coupling 1, a cam member 18 provided with cam portions 18 b, 18 b that abut against the rollers 7, 7 of the cam follower members 6, 6 is provided. The cam portions 18b and 18b of the cam member 18 respectively have cam surfaces 18d formed of point-symmetrical circular arcs across the axis of the output shaft 4 at positions where the rollers 7 abut. The arc is shaped so as to gradually approach the axis of the output shaft 4 in the forward rotation direction, ie, the tightening direction shown in FIG. 6, and the cam surface 18d rotates the roller 7 by the arc. Function to retract in a direction intersecting with the center line of the input shaft 3, that is, the axis of the input shaft 3 (see FIG. 6). Further, since the cam surface 18d acts to retract the roller 7, the pressing force of the cylinder portion 8 is increased to increase the braking force applied to the roller 7, whereby the relative rotation of the cam portion 18b is performed. It acts to be able to brake the movement.

  A bearing plate 19 is fixed to the two cam portions 18 b and 18 b described above, and the input shaft 3 is rotatably held by the bearing plate 19, and relative between the input shaft 3 and the output shaft 4 The pivoting is guided (see FIG. 4). Further, a spring locking block 20 is attached to the inside of the bearing plate 19, and one end of the spring locking block 20 is locked by the other end of the coil spring 5f locked to the connecting collar 3b. (See FIG. 10). The coil spring 5 f acts in a direction to restore relative rotation between the bearing plate 19 and the expanded diameter shaft portion 5 when the impact torque applied to the output shaft 4 is eliminated or becomes smaller. Even if relative rotation occurs between the shaft and the output shaft 4 to cause a phase difference between the two shafts, the phase difference between the two shafts can be quickly eliminated. As a result, the relative rotation between the cam member 18 integral with the bearing plate 19 and the roller 7 is restored, so even if the driver bit 76 rises as the driver base rises and returns when the tightening is completed, A configuration is obtained in which the post-engagement member 78 is not lifted together with the later-described screw 77.

  The output shaft 4 of the shaft coupling 1 is rotatably held by the driver attachment 73, and the rotation of the shaft coupling 1 within the driver attachment 73 is secured. The output shaft 4 projects downward through the air gap 72a of the driver stand 72, and a driver bit 76 is connected to the lower end thereof. The driver bit 76 is lowered together with the driver base 72, and pushes out the screw 77 of an example of the fastener held by the pair of chuck claws (not shown) from the chuck claws, and the tip thereof is screwed into the screw hole 79a It is configured to be located at In addition. The shaft joint 1 connected between the connecting shaft 75 and the driver bit 76 which are rotated by the rotation of the motor 74 may be connected with the input shaft 34 and the output shaft reversed.

  In the component fastening machine, when the motor 74 rotates at a predetermined rotational speed, the rotation of the drive shaft is transmitted to the input shaft 3 of the shaft coupling 1 via the connecting shaft 75. When the input shaft 3 is rotated and the cam follower member 6 held by the lower diameter expanded shaft portion 5 is rotated, the braking force applied by the roller 7 at the tip to the cam portion 18b of the cam member 18 causes the cam member 18 to rotate. And the output shaft 4 rotate in unison. During this time, as shown in FIG. 24, the driver stand 72 is lowered, and the driver bit 76 is lowered integrally with this. Along with this, the driver bit 76 engages with the drive hole 77a of the screw 77 held by the pair of chuck claws, and rotates the screw 77. In this state, the driver bit 76 is further lowered to push the screw 77 out of the chuck claw. At the same time, the tip of the screw 77 passes through the lower hole 78a of the fastened member 78 and is positioned in the screw hole 79a of the mating member 79, so that the screw 77 is tightened to the mating member 79.

  When the screw 77 is tightened to the mating member 79 and its head is seated on the fastened member 78 as shown in FIG. 25, the rotational speed of the driver bit 76 is rapidly reduced and the shaft coupling connected to the driver bit 76 The output shaft 4 of 1 is also rapidly decelerated. At this time, as the rotational speed of the motor 74 increases, a large impact torque in the direction in which the motor 74 is braked, that is, in the direction opposite to the tightening direction is generated. When the rotational force by this impact torque becomes larger than the braking force between the cam portion 18 b of the cam member 18 and the roller 7 of the cam follower member 6, the output shaft 4 moves to the input shaft 3, that is, the cam portion 18 b contacts the roller 7. It is relatively rotated in the direction opposite to the tightening direction (see FIG. 12). Therefore, the roller 7 relatively rotates while following the cam surface 18d of the cam portion 18b, and retracts in a direction intersecting the center line of the rotation, that is, the axis of the input shaft 3. By the backward movement of the roller 7, the cylinder portion 8 temporarily increases its pressing force while performing a damper function. As the pressing force of the cylinder portion 8 increases, the braking force applied to the roller 7 increases, and the rotation of the cam portion 18b is braked by the increased braking force. Since the impact torque applied from the output shaft 4 to the cam portion 18b of the cam member 18 is reduced by the braking of the cam portion 18b and transmitted to the input shaft 3, an impact torque large in the direction of applying the motor 74 is applied. Can not participate. Thereby, when detecting the load current applied to the motor 74 and controlling the tightening torque, even if the rotational speed of the motor 74 is increased, the load current of the motor 74 is not affected by the impact torque, and thus the tightening is performed. The load current of the motor 7 suitable for torque control can be obtained. Further, even when a large impact torque (see impact torque T1 in the case of the conventional component fastening machine shown in FIG. 27) occurs when the head of the screw 77 is seated on the fastened member 78, this impact torque T1 is a torque Since it is reduced to the value Tr and transmitted to the motor 74 side (see FIG. 26), the torque value T2 below the impact torque T1 which could not be controlled can also be subjected to tightening torque control, and high speed and wide setting A range of tightening torque control can be performed.

  Although the first to fifth embodiments of the present invention have been described, the specific configuration of each part is not limited to only the above-described embodiment, and the scope of the present invention is not deviated from it. Various modifications are possible.

1 ... shaft coupling,
2 ... Drive axis,
3 ... Input axis,
4 ... Output axis,
6 ... cam follower member,
18 ... cam member,
18d ... cam surface,
51 damper device,
61 shock absorber,
71 Parts Fastening Machine,

Claims (10)

A cam follower member, which is disposed on one of two members which relatively rotate so as to rotate integrally therewith and which is retractably biased in a direction crossing the center line of the rotation, and the other member And a cam member disposed to rotate integrally with the cam member, and the cam follower member is brought into contact with the cam surface of the cam member, and the cam follower member is rotated by relative rotation between the two members. A shaft coupling configured to move in a direction intersecting with a center line to increase or decrease a braking force to the rotation.   The shaft coupling according to claim 1, wherein the cam follower member is connected to a damper unit that increases a braking force by a viscous fluid.   The cam follower member is held by a cylinder portion forming a damper portion in which the braking force increases when it is retracted, and the cylinder portion is movably held by the member on which the cam follower member is disposed, and the piston therein is fixed to the member The shaft coupling according to claim 2, wherein the shaft coupling is locked to the piston rod, and the piston has a port through which the viscous fluid in the cylinder portion passes.   The shaft coupling according to any one of claims 1 to 3, wherein the cam member is biased by a coil spring acting in a direction of returning relative rotation between the cam follower member and the cam member.   The two cam follower members are provided point-symmetrically at positions sandwiching the center line of relative rotation with the cam members, and the cam members are arranged with respect to each cam follower member. The shaft coupling according to any one of claims 1 to 4.   5. The cam member according to claim 1, wherein the cam member has a cam surface corresponding to rotation in both forward and reverse directions of the cam follower member, and the cam follower member abuts near the center of the cam surface. The shaft coupling described in any one. A cam follower member, which is disposed so as to be retractably urged in a direction intersecting with the center line of the rotation, to one of two members which are relatively rotated, is connected to the other member, and the cam follower member abuts And a cam member having a cam surface, wherein the cam follower member and the member on which the cam follower is disposed , the cam member and the member on which the cam follower is disposed rotate integrally, and the cam surface is between the two members The cam follower member is configured to be advanced or retracted in the direction intersecting the center line of the pivot against the resilient biasing means by relative pivoting, and the braking force to the pivot is increased in the cam follower member, or A damper device characterized in that it is configured to be applied in a reduced manner. A member that rotates in response to the rotation of the rotational drive source and any one member of the working tool that rotates in response to the rotation are capable of rotating integrally with the member and retractable in a direction intersecting the center line of the rotation A cam follower member arranged to be biased and a cam member arranged to rotate integrally with the other member so as to rotate relative to the cam follower member, and the cam surface of the cam member is provided The cam follower member is brought into contact, and the relative rotation between the cam member and the cam follower member causes the cam follower member to retract in a direction intersecting the center line of the rotation to increase the braking force to the rotation. Impact torque reduction device characterized in that. A member rotating in response to rotation of the drive shaft of the rotational drive source and one member of the work tool rotating in response to the rotation so as to rotate integrally therewith and in a direction intersecting the center line of the rotation The cam member includes a cam follower member which is disposed so as to be capable of retracting, and a cam member which is integrally rotated with the other member so as to rotate relative to the cam follower member. The cam follower member is brought into contact with the cam surface of the cam, and the cam follower member is retracted in a direction intersecting the center line of the pivot by relative pivoting between the cam member and the cam follower, and the braking force to the pivot A parts fastening machine characterized in that it is configured to increase.   10. The part fastening machine according to claim 9, wherein the cam member is biased by a coil spring acting in a direction of returning relative rotation with the cam follower member.

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