JP2010280008A - Fastening device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fastening device allowing a head to be adjusted to a predetermined rotational phase when the head is held at a magazine again after a bolt is fastened. <P>SOLUTION: The fastening device includes: a rotating part 40 for rotating a socket 41; an advance/retract driving part for advancing/retracting the socket 41 along a rotating axis; and the magazine 10 for holding the head 20 holding bolts B at each of plural head storage parts 111. Protrusions 114 are arranged at the inner circumferential surface of the head storage part 111. A step 415 is formed from the base end edge of the socket 41 to the tip edge thereof on the outer circumferential surface of the socket 41. When the socket 41 is retracted and is pulled out from the head storage part 111, the protrusion 114 engages with the step 415 of the socket 41. Thereafter, as the socket 41 retracts, the step 415 of the socket 41 is pressed by the protrusion 114 so that the socket 41 is rotated. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fastening device. Specifically, the present invention relates to a fastening device for fastening screws and bolts.

  2. Description of the Related Art Conventionally, in a manufacturing process of an automobile, parts are fixed at a plurality of locations with screws or bolts using a tightening device. For example, the tightening device includes a robot arm and a nutrunner provided at the tip of the robot arm (see Patent Document 1). Then, the bolt is held by the socket of the nut runner, and when the parts are transported while being temporarily fixed to the workpiece, the robot arm is controlled to insert the bolt held by the nut runner into a predetermined portion of the workpiece. Then, a socket is rotated and a bolt is tightened (refer patent document 1).

  By the way, in recent years, a plurality of types of vehicles are manufactured on one line, and therefore, it is required to tighten a plurality of types of bolts with a single tightening device. Therefore, the following tightening device has been proposed (see Patent Document 1).

  That is, the tightening device of Patent Document 1 includes a flat plate-like magazine on which a head is mounted, and a nut runner disposed below the magazine. Bolts are held on the head. According to this tightening device, first, the rotary shaft of the nut runner is raised and fitted to the head, and the head is attached to the tip of the rotary shaft. Next, the nut runner is moved, the head attached to the tip of the nut runner is raised a little, and then the head is removed from the magazine by moving in the horizontal direction. Thereafter, the nut runner is raised again, the head is brought close to a predetermined position of the work, and the bolt is tightened. Then, the nut runner is lowered and the head is mounted on the magazine again.

Japanese Patent Laid-Open No. 7-60567

  By the way, in the structure shown in Patent Document 1, there is a problem that the rotational phase of the head does not become constant when the head is mounted on the magazine after the bolt is tightened.

  An object of the present invention is to provide a tightening device that can adjust a head to a predetermined rotational phase when the head is held again in a magazine after the bolt is tightened.

  A tightening device (for example, a tightening device 1 described later) of the present invention is a rotational drive unit (for example, described later) that rotates a cylindrical socket (for example, a socket 41 described later) about the central axis of the socket as a rotation axis. Rotation drive unit 40), an advance / retreat drive unit (for example, a later-described advance / retreat drive unit 50) for moving the socket back and forth along the rotation axis, and a plurality of through holes (for example, a later-described head storage unit 111). Each of the plurality of through-holes includes a magazine (for example, a magazine 10 to be described later) that stores and holds a head (for example, a head 20 to be described later), and the head includes a fastening member (for example, a bolt to be described later). B), a protrusion (for example, a protrusion 114 described later) is provided on the inner peripheral surface of the through hole, and a step (from the base edge to the tip edge of the socket) is provided on the outer peripheral surface of the socket. For example, Difference 415) is formed, and the socket is advanced by the advance / retreat drive unit and penetrates the through hole, whereby the head is held inside the socket and detached from the magazine, and the rotation drive unit The head is rotated by rotating the head, the fastening member held by the head is tightened, the socket is retracted by the advance / retreat drive unit, and the socket is pulled out from the through hole. When the socket is retracted and the socket is retracted and pulled out from the through hole, the protrusion engages with the step of the socket, and then the protrusion of the socket is pressed by the protrusion as the socket retracts. And the socket rotates.

According to the present invention, when the socket is retracted and pulled out from the through hole, the protrusion engages with the step of the socket, and thereafter, as the socket retracts, the step of the socket is pressed by the protrusion and the socket rotates.
Therefore, when the head is held again in the magazine after the bolt is tightened, the head can be adjusted to a predetermined rotational phase with respect to the magazine.

  In this case, when the socket is advanced to pass through the through-hole, the protrusion engages with the step of the socket, and then, as the socket advances, the protrusion of the socket is pressed by the protrusion. It is preferred that the socket rotates.

According to this invention, when the socket is advanced to pass through the through hole, the protrusion engages with the step of the socket, and then, as the socket advances, the step of the socket is pressed by the protrusion and the socket rotates. .
Therefore, when the socket is inserted into the magazine, the socket can be adjusted to a predetermined rotational phase with respect to the head.

  In this case, it is preferable that the rotation driving unit is provided with a one-way clutch (for example, a one-way clutch 421 described later) that idles the socket in only one direction.

  According to the present invention, since the one-way clutch is provided in the rotation drive unit, when the socket is pressed and rotated by the protrusion, it is not necessary to rotate the entire rotation drive unit, and the socket can be rotated with a small pressing force. As a result, the operation of the tightening device becomes smooth.

  In this case, when the socket is retracted and pulled out from the through hole, it is preferable that the protrusion engages the head to restrict the head from retracting.

  According to the present invention, when the socket is retracted and pulled out from the through hole, the protrusion is engaged with the head to restrict the head from being retracted, so that the head can be prevented from being pulled out of the magazine together with the socket.

  According to the present invention, when the socket is retracted and pulled out from the through hole, the protrusion engages with the step of the socket, and then, as the socket retracts, the step of the socket is pressed by the protrusion and the socket rotates. Therefore, when the head is held again in the magazine after the bolt is tightened, the head can be adjusted to a predetermined rotational phase with respect to the magazine.

It is a perspective view which shows the clamping apparatus which concerns on one Embodiment of this invention. It is sectional drawing of the clamping apparatus which concerns on the said embodiment. It is a front view of the magazine of the clamping device concerning the embodiment. It is an enlarged plan view of a portion in which the head of the magazine according to the embodiment is stored. It is an expanded sectional view of the part in which the head of the magazine concerning the embodiment is stored. It is a perspective view of the socket of the clamping device concerning the embodiment. It is FIG. (1) for demonstrating operation | movement of the clamping apparatus which concerns on the said embodiment. It is a perspective view (the 1) for demonstrating operation | movement of the socket of the clamping apparatus which concerns on the said embodiment. FIG. 6 is a diagram (No. 2) for explaining the operation of the fastening device according to the embodiment. FIG. 6 is a diagram (No. 3) for explaining the operation of the fastening device according to the embodiment. It is a perspective view (the 2) for demonstrating operation | movement of the socket of the clamping apparatus which concerns on the said embodiment. It is FIG. (4) for demonstrating operation | movement of the clamping apparatus which concerns on the said embodiment. It is FIG. (5) for demonstrating operation | movement of the clamping apparatus which concerns on the said embodiment. It is sectional drawing and the front view of the head which concern on the modification of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an outline of a fastening device 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the tightening device 1.
The tightening device 1 is a device for tightening a bolt B as a tightening member, and is provided at the tip of the robot arm 2.
The tightening device 1 includes a rotation drive unit 40 that rotationally drives a socket 41, an advance / retreat drive unit 50 that advances and retracts the socket 41 of the rotation drive unit 40 along a rotation axis, and a magazine 10 that holds eight heads 20. And a switching unit 30 that rotates the magazine 10 to selectively position one of the heads 20 in front of the socket 41 and on the rotation axis.

  The robot arm 2 is controlled by the control device 60 and changes the position and posture of the tightening device 1 in the three-dimensional space.

FIG. 3 is a front view of the magazine 10.
As shown in FIG. 3, the magazine 10 includes a disk-shaped base portion 11, an attaching / detaching portion 12 provided at the center on the back side of the base portion 11, and the above-described 8 arranged along the outer peripheral surface of the base portion 11. Individual heads 20.
Eight through holes are formed at predetermined intervals along the outer periphery of the base 11, and these through holes serve as head storage portions 111, respectively.

Each head 20 is housed and held in the head housing portion 111 so as to be detached from the magazine 10 when it moves in the forward direction of the socket 41. Bolts B are held on these heads 20 (see FIG. 4).
The detachable part 12 is a so-called auto tool changer.

  The switching unit 30 supports the magazine drive unit 31 by being attached to the front end flange surface of the robot arm 2 and the magazine drive unit 31 that rotates and the attachment / detachment unit 32 provided at the front end of the rotation shaft of the magazine drive unit 31. Mounting bracket 33.

The attachment / detachment unit 32 is a so-called auto tool changer, and the attachment / detachment unit 12 of the magazine 10 is attached / detached.
The magazine drive unit 31 is driven by the control device 60. By attaching the attaching / detaching part 12 of the magazine 10 to the attaching / detaching part 32 of the switching part 30 and driving the magazine driving part 31, the center of the magazine 10 is rotated about the rotation axis Y and the head 20 is moved.

The rotation drive unit 40 includes the cylindrical socket 41 described above, a rod-shaped shaft portion 42 connected to the socket 41, and a drive portion 43 that rotates the shaft portion 42.
A one-way clutch 421 is provided on the shaft portion 42. The one-way clutch 421 rotates idly when viewed clockwise from the base end side of the shaft portion 42, and meshes when rotated counterclockwise.
The drive unit 43 rotates the shaft portion 42 with the central axis of the socket 41 as the rotation axis X. The rotation axis X is substantially parallel to the rotation axis Y of the magazine 10.
Further, a spring 44 for floating the socket 41 is interposed between the drive unit 43 and the socket 41.

The advance / retreat drive unit 50 is provided on the mounting bracket 33 of the switching unit 30 and is controlled by the control device 60 to move the rotation drive unit 40 forward or backward along the rotation axis X.
The advance / retreat drive unit 50 includes a cylinder mechanism 51 and a pair of slide guides 52.

  The pair of slide guides 52 includes a slide beam 521 attached to the rotation driving unit 40 and a slide guide 522 provided on the attachment bracket 33 and through which the slide beam 521 is inserted. The pair of slide guides 52 guides the rotation drive unit 40 when the slide beam 521 slides in the slide guide 522.

  The cylinder mechanism 51 includes a piston rod 511 attached to the rotation drive unit 40 and a cylinder 512 that moves the piston rod 511 forward and backward. By driving the cylinder mechanism 51, the rotation drive unit 40 moves forward and backward.

4 is an enlarged plan view of a portion of the magazine 10 in which the head 20 is accommodated, and FIG. 5 is an enlarged cross-sectional view of a portion of the magazine 10 in which the head 20 is accommodated. FIG. 5 shows a state in which the socket 41 is inserted into the head storage portion 111 of the magazine 10.
Plungers 112 having retractable balls 113 are provided at three locations on the front side of the inner peripheral surface of the head storage portion 111 of the magazine 10. The ball 113 is urged in a direction protruding from the inner peripheral surface of the head storage portion 111 by a spring (not shown).
In addition, on the back side of the magazine 10 on the inner peripheral surface of the head storage portion 111, three protrusions 114 are provided so as to protrude from the plunger 112.

The head 20 includes a columnar head main body 21 and a disc-shaped flange portion 22 formed on the distal end side of the head main body 21 and having a larger outer diameter than the head main body 21.
A hexagonal recess is formed on the tip surface of the head 20, and this recess serves as a bolt holding portion 23 into which the head of the bolt B is fitted. A magnet 24 is attached to the bottom surface of the bolt holding portion 23, and the bolt B is held by the magnetic force of the magnet 24.

At three locations on the outer peripheral surface of the flange portion 22, concave portions 221 with which the balls 113 of the plunger 112 are engaged are formed.
The wall surface on the distal end side of the head 20 of the recess 221 is a vertical surface 222 that is substantially perpendicular to the axial direction of the head 20, and the wall surface on the proximal end side of the head 20 of the recess 221 is inclined with respect to the axial direction of the head 20. This is a tapered surface 223.

  Plungers 211 having balls 212 that can be projected and retracted are provided at three locations on the outer peripheral surface of the head main body 21. The ball 212 is urged in a direction protruding from the outer peripheral surface of the head body 21 by a spring (not shown).

A concave portion is formed on the front end surface of the socket 41 of the rotation driving unit 40, and this concave portion serves as a head holding portion 411 in which the head main body 21 of the head 20 is fitted and held.
A concave portion 412 that engages with the ball 212 of the plunger 211 is formed on the inner peripheral surface of the head holding portion 411.
The wall surface on the distal end side of the socket 41 of the concave portion 412 is a tapered surface 413 inclined with respect to the axial direction of the socket 41, and the wall surface on the proximal end side of the socket 41 in the concave portion 412 is substantially perpendicular to the axial direction of the socket 41. This is a vertical surface 414.

FIG. 6 is a perspective view of the socket 41.
On the outer peripheral surface of the socket 41, two steps 415 from the base edge to the tip edge are provided. These steps 415 can lock the projections 114 of the magazine 10.
Specifically, each of the steps 415 is continuous with the first guide portion 415a extending from the base edge toward the distal end in a counterclockwise direction when viewed from the shaft portion 42 side, and the first guide portion 415a. A holding portion 415b that extends substantially parallel to the central axis of the socket 41, and a second guide portion 415c that continues to the holding portion 415b and extends clockwise from the shaft portion 42 side to the tip edge.
Further, the socket 41 is idled in the clockwise direction as viewed from the shaft portion 42 side by the one-way clutch 421 as indicated by an arrow in FIG.

Next, operation | movement of the above-mentioned clamping apparatus 1 is demonstrated.
As an initial setting, it is assumed that bolts B are attached to all the heads 20 of the magazine 10.
First, the robot arm 2 is controlled by the control device so as to avoid an obstacle and move so that the first attachment position is located on the rotation axis X of the fastening device 1.
Further, the switching unit 30 is driven to rotate the magazine 10 so that one of the plurality of heads 20 is selectively positioned on the rotation axis of the socket 41.

  Next, as shown in FIG. 7, the advancing / retreating drive unit 50 is driven so that the socket 41 approaches the head storage unit 111 of the magazine 10 and is inserted into the head storage unit 111. Then, as shown in FIG. 8A, the base end edge of the projection 114 of the magazine 10 is engaged with the second guide portion 415 c of the step 415 of the socket 41.

  When the socket 41 is further advanced, as shown in FIG. 8B, the projection 114 of the magazine 10 moves to the proximal end side of the socket 41 along the second guide portion 415c. At this time, since the second guide portion 415c extends clockwise as viewed from the shaft portion 42 side from the proximal end side to the distal end side, the second guide portion 415c is pressed by the protrusion 114, and the socket 41 is moved to FIG. Rotate in the direction indicated by the middle arrow. The rotation direction of the socket 41 is the idling direction by the one-way clutch 421.

  Thereafter, as shown in FIG. 8C, when the projection 114 of the magazine 10 reaches the holding portion 415 b, the holding portion 415 b extends substantially parallel to the central axis of the socket 41, and is pressed by the projection 114. Without rotation, the rotation of the socket 41 ends. Due to the rotation of the socket 41, the recess 412 of the socket 41 is positioned on an extension line of the plunger 211 of the head 20 in the rotation axis X direction.

  Thereafter, as shown in FIG. 9, the socket 41 is completely inserted into the head storage portion 111. Then, the plunger 211 of the head 20 engages with the recess 412 of the socket 41, and the socket 41 holds the head 20.

  Further, as shown in FIG. 10, the advancing / retreating drive unit 50 is driven to advance the socket 41, and the socket 41 is passed through the head storage unit 111.

  At this time, the plunger 211 of the head 20 is engaged with the vertical surface 414 of the concave portion 412 of the socket 41, and the plunger 112 of the magazine 10 is engaged with the tapered surface 223 of the concave portion 221 of the head 20. Therefore, the force for pressing and moving the head 20 by the socket 41 is larger than the force for suppressing the movement of the head 20 by the magazine 10.

  Therefore, the engagement between the concave portion 221 of the head 20 and the plunger 112 of the magazine 10 is released, and the head 20 is detached from the magazine 10 and moves together with the socket 41 to the front side of the magazine 10.

  Then, the drive part 43 of the rotation drive part 40 is driven, the head 20 is rotated, and the volt | bolt B is fastened to a 1st attachment position.

  After completing the tightening of the bolt B, the drive of the drive unit 43 of the rotation drive unit 40 is stopped, the advance / retreat drive unit 50 is driven, and the socket 41 is retracted this time. Then, as shown in FIG. 11A, the leading edge of the projection 114 of the magazine 10 is engaged with the first guide portion 415 a of the step 415 of the socket 41.

  When the socket 41 is further retracted, the projection 114 of the magazine 10 moves to the distal end side of the socket 41 along the first guide portion 415a. At this time, since the first guide portion 415a extends counterclockwise as viewed from the shaft portion 42 side from the proximal end side toward the distal end side, the first guide portion 415a is pressed by the protrusion 114, and the socket 41 is shown in FIG. ) Rotate in the direction indicated by the middle arrow. The rotation direction of the socket 41 is the idling direction by the one-way clutch 421.

  Thereafter, as shown in FIG. 11C, when the projection 114 of the magazine 10 reaches the holding portion 415 b, the holding portion 415 b extends substantially parallel to the central axis of the socket 41, so that it is pressed by the projection 114. Without rotation, the rotation of the socket 41 ends. Due to the rotation of the socket 41, the recess 221 of the head 20 is positioned on an extension line in the rotation axis X direction of the plunger 112 of the magazine 10.

  Thereafter, as shown in FIG. 12, the head 20 moves backward together with the socket 41, the concave portion 221 of the head 20 engages with the plunger 112 of the magazine 10, and the head 20 is held by the magazine 10 again.

  Further, as shown in FIG. 13, the advancing / retreating drive unit 50 is driven to retract the socket 41, and the socket 41 is pulled out from the head storage unit 111.

  At this time, the plunger 211 of the head 20 is engaged with the vertical surface 414 of the concave portion 412 of the socket 41, and the plunger 112 of the magazine 10 is engaged with the vertical surface 222 of the concave portion 221 of the head 20. Therefore, the force with which the magazine 10 holds the head 20 is greater than the force with which the socket 41 holds the head 20.

Further, the projection 114 of the magazine 10 is engaged with the flange portion 22 of the head 20, and the backward movement of the head 20 is restricted.
Therefore, the engagement between the plunger 211 of the head 20 and the recess 412 of the socket 41 is released, the head 20 is held by the magazine 10, the head 20 is detached from the socket 41, and only the socket 41 is retracted.

  Thereafter, the control device 60 controls the robot arm 2 to avoid the obstacle, and moves the tightening device 1 to the vicinity of the second attachment position of the bolt B, and repeats the same operation as described above.

According to this embodiment, there are the following effects.
(1) When the socket 41 is retracted and pulled out from the head accommodating portion 111, the protrusion 114 engages with the step 415 of the socket 41, and thereafter, the protrusion 114 presses the step 415 of the socket 41 as the socket 41 retracts. Thus, the socket 41 rotates.
Therefore, when the head 20 is held again in the magazine 10 after the bolt B is tightened, the head 20 can be adjusted to a predetermined rotational phase with respect to the magazine, and the concave portion 221 of the head 20 is securely attached to the plunger 112 of the magazine 10. Can be engaged.

(2) When the socket 41 is moved forward to penetrate the head housing 111, the protrusion 114 engages with the step 415 of the socket 41, and then the protrusion 114 presses the step 415 of the socket 41 as the socket 41 advances. As a result, the socket 41 rotates.
Therefore, when the socket 41 is inserted into the magazine 10, the socket 41 can be adjusted to a predetermined rotational phase with respect to the head 20, and the concave portion 412 of the socket 41 can be reliably engaged with the plunger 211 of the head 20. .

  (3) Since the one-way clutch 421 is provided in the rotation drive unit 40, when the socket 41 is pressed and rotated by the protrusion 114, it is not necessary to rotate the entire rotation drive unit 40, and the socket 41 is rotated with a small pressing force. Therefore, the operation of the tightening device 1 becomes smooth.

  (4) When the socket 41 is retracted and pulled out from the head storage portion 111, the protrusion 114 is engaged with the head 20 to restrict the head 20 from being retracted. Can be prevented.

It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.
For example, in the present embodiment, the head 20 has a structure that holds the bolt B. However, the present invention is not limited to this, and the head 20A may have a structure that holds a screw as shown in FIG. That is, a substantially cross-shaped projecting portion is formed on the tip surface of the head 20A, and this projecting portion serves as a screw holding portion 25 into which a screw head is fitted. A magnet 26 is attached around the screw holding portion 25, and the screw is held by the magnetic force of the magnet 26.

B bolt (clamping member)
DESCRIPTION OF SYMBOLS 1 Tightening apparatus 10 Magazine 20 Head 40 Rotation drive part 41 Socket 50 Advance / retreat drive part 111 Head accommodating part (through-hole)
114 Protrusion 415 Step 421 One-way clutch

Claims (4)

A rotational drive unit that rotationally drives a cylindrical socket with the central axis of the socket as a rotational axis;
An advancing / retreating drive unit for advancing and retracting the socket along the rotation axis;
A magazine having a plurality of through holes and storing and holding a head in each of the plurality of through holes,
The head holds a fastening member;
A protrusion is provided on the inner peripheral surface of the through hole,
On the outer peripheral surface of the socket, a step is formed from the base edge of the socket to the tip edge,
By moving the socket forward by the advance / retreat drive unit and penetrating the through hole, the head is held inside the socket and detached from the magazine, and the head is rotated by the rotation drive unit. The fastening member held by the head is tightened, the socket is retracted by the advance / retreat drive unit and pulled out from the through hole, so that the head is again held by the magazine and detached from the socket,
When the socket is retracted and pulled out from the through hole, the protrusion engages with the step of the socket, and then, as the socket retracts, the step of the socket is pressed by the protrusion and the socket rotates. A fastening device characterized by that. The fastening device according to claim 1,
When the socket is advanced to pass through the through hole, the protrusion engages with the step of the socket, and then, as the socket advances, the step of the socket is pressed by the protrusion and the socket rotates. A fastening device characterized by that. The tightening device according to claim 1 or 2,
The fastening device according to claim 1, wherein the rotary drive unit is provided with a one-way clutch that idles the socket in only one direction. The fastening device according to any one of claims 1 to 3,
When the socket is retracted and pulled out from the through hole, the protrusion engages with the head and restricts the retracting of the head.

Images