JP2006142413A - Screw member-feeding/tightening device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a screw member-feeding/tightening device improving universality by preventing enlargement. <P>SOLUTION: A bolt holding means 20 rotates a rotating member in steps so that each of chuck mechanisms 27 sequentially stops at a position where a bolt B is delivered to a rotation axis 8 as a socket part 87 is engaged with the bolt B when moving the rotation axis 8 to the side of a work. A chuck device to hold the bolt B against each of the chuck mechanisms 27 of the bolt holding means 20 in a state free to receive and deliver it is provided on a bolt feeding device. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for supplying a screw member to a screw member tightening device that performs tightening by attaching a screw member to the tip of a rotating shaft.

An apparatus for supplying a screw member to a screw member fastening apparatus is described in Patent Document 1. In this apparatus, a tape with a large number of screws attached is accommodated in a tape cassette, and this tape cassette is arranged on the side of the screw member fastening device. Then, the tape is pulled out from the tape cassette below the bit of the screw member fastening device, the bit is lowered, and its tip is engaged with the head of the screw to tighten the screw.
Japanese Patent Laid-Open No. 2-205422 (FIG. 1)

  However, this apparatus needs to secure an arrangement space for the tape cassette around it, and the size of the apparatus cannot be avoided. That is, the operation is restricted in order to avoid interference with other devices during work, and it is difficult to apply except when a small screw member is used, and there is a problem in versatility.

  In view of such circumstances, an object of the present invention is to provide a screw member supply and tightening device that prevents an increase in size of the device and improves versatility.

  According to the present invention for solving the above-described problem, a screw member is attached to the engaging portion at the tip of the rotating shaft connected to the driving means, and the screw member is moved to the workpiece side by moving the rotating shaft toward the workpiece. A screw member supply and tightening device comprising: a screw member tightening means for screwing; and a screw member supply means for supplying the screw member to the screw member tightening means. A rotation provided with a plurality of chuck mechanisms for holding the screw members. When a member is provided on the screw member fastening means and the rotating shaft is moved to the workpiece side, the engaging portion engages with the screw member, and the screw member is transferred to the rotating shaft. Screw member holding means for stepwise rotating the rotating member so that the chuck mechanisms stop sequentially, and the screw member supply means, and deliver the screw member to each chuck mechanism of the screw member holding means. Characterized by comprising a screw member supply ready means for holding in a potential state.

  According to such a configuration, when the screw member is supplied from the screw member supply means to the screw member tightening means, the screw member holding means is brought close to the screw member supply preparation means, and the screw members are held by the respective chuck mechanisms. To the screw member holding means. Next, when the rotating shaft is moved to the work side, the engaging portion at the tip thereof is engaged with the screw member, and the screw member is held by the rotating shaft. When the screwing of the screw member is completed, the rotating shaft is temporarily retracted, and the rotating member is rotated until the next screw member comes to the delivery position on the extension line of the rotating shaft.

  According to the present invention, since the number of screw members necessary for the work is supplied from the screw member supply means to the screw member holding means, even if the screw member to be used is large, it is not necessary to make the screw member holding means too large. The increase in the size of the device can be suppressed, which helps improve versatility.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing the entire screw member fastening device of the present invention.

  In this screw member fastening device 1, a motor 2, a bearing mechanism 3, and a joint mechanism 4 are integrated to form a rotational drive unit 5, and the rotational drive unit 5 is movable along a guide rail 6 while being movable. Is assembled. The guide rail 6 is disposed along the longitudinal direction of the base plate 7. An output shaft (not shown) of the motor 2 is connected to the rotary shaft 8 via the speed reducer 3 and the joint mechanism 4. The rotating shaft 8 protrudes from the housing 4 a of the joint mechanism 4 and extends along the longitudinal direction of the base plate 7.

  A ball screw 9 extending along the rotation shaft 8 is attached to the base plate 7 using support members 10 and 10. Then, the ball screw 9 is connected to the stepping motor 11, and the moving body 12 screwed to the ball screw 9 is connected to the rotation drive unit 5, whereby the rotation drive unit 5 is driven by the stepping motor 11 to the guide rail 6. It is comprised so that it may move along.

  2 is an enlarged view of the bolt holding means of FIG. 1, FIG. 3 is a view of the bolt holding means of FIG. 2 viewed from the back side, and FIG. 4 is a cross-sectional view showing a state where the claw member holds the bolt.

  The base plate 7 is provided with a bolt holding means 20 at the end of the rotary shaft 8 on the tip side. The bolt holding means 20 supports a rotating member 22 rotatably on a bracket 21 erected on the base plate 7. A pulley 23 is attached to the rotating shaft 22a of the rotating member 22 at a portion protruding to the back side of the bracket 21 (see FIG. 3). The stepping motor 25 is attached to the bracket 24 erected on the base plate 7, the pulley 26 is attached to the output shaft 25 a of the stepping motor 25, and the timing belt 37 is installed between the pulley 26 and the pulley 23 on the rotating member 22 side. By doing so, the rotating member 22 is configured to be rotationally driven by the stepping motor 25.

  A chuck mechanism 27 is disposed on the rotating member 22 at four equally spaced locations in the circumferential direction. The chuck mechanism 27 includes a chuck body 28 fixed to the rotating member 22 and a pair of claw members 29 and 29 provided on the chuck body 28 so as to hold the bolt B. The rotating member 22 rotates in 90-degree steps so that the four bolts B held by the chuck mechanism 27 are sequentially stopped at a position that coincides with the extension line of the rotating shaft 8. The chuck body 28 includes a holding portion 28a fastened and fixed to the rotating member 22 by a bolt 30, another holding portion 28b disposed opposite to the holding portion 28a, and a cylindrical portion 28c integrally formed on the back side of the holding portions 28a and 28b. (See FIG. 3).

  The pair of claw members 29 and 29 are accommodated between the holding portions 28a and 28b of the chuck main body 28, and the base end portions of the claw members 29 and 29 are pivotally coupled by the pins 31, while the claw members 29 and 29 are connected. Each claw member 29, 29 is urged in the closing direction with a spring 32 interposed between the base end portion and the cylindrical portion 28c. A cam portion 29 a is formed at the base end portion of the claw member 29. Further, a circumferential groove 29b is formed on the back surface of the claw member 29, and when the claw member 29 is closed, the circumferential groove 29b engages with the flange portion f of the bolt B to clamp the bolt B ( (See FIGS. 4 and 10). A hole 29c through which the shaft portion j of the bolt B is passed is formed at the tip of the claw member 29.

  A pair of arm members 33 are attached to the housing 4 a of the joint mechanism 4 so as to sandwich the rotating shaft 8, and rollers 34 are respectively installed at the ends of the arm members 33 and 33. Then, as the rotary drive unit 5 advances, the roller 34 rides on the cam portion 29a of the claw member 29 and opens the claw member 29.

  FIG. 5 is an enlarged perspective view showing the housing 3a and 4a of the bearing mechanism 3 and the joint mechanism 4 in FIG. 1 in a cutaway manner, and FIG. 6 is a diagram for explaining the operation of the joint mechanism 4.

  The joint mechanism 4 is configured by a universal joint having a pair of rotating shafts 50 and 51 perpendicular to each other. That is, the first connecting member 52 is supported so as to be rotatable around the rotation shaft 50 with respect to the second connecting member 53. The third connecting member 54 is supported so as to be rotatable around the rotation shaft 51 with respect to the second connecting member 53.

  The first connecting member 52 has a substantially U-shaped cross section, and connects the main body 52a to the tip of the output shaft (not shown) of the bearing mechanism 3 and is connected between the pair of support portions 52b and 52b. The two connecting members 53 are accommodated and are pivotally coupled by a pin (rotating shaft) 50 (see FIG. 6). The second connecting member 53 includes a main body portion 53a through which the two pins 50 and 51 are inserted, and locking portions 53b and 53c extending from both ends of the main body portion 53a along the pins 50 and 51, respectively. . The third connecting member 54 has a substantially U-shaped cross section, and connects the main body portion 54a to the base end of the rotary shaft 8 and houses the second connecting member 53 between the pair of support portions 54b and 54b. A pin (rotating shaft) 51 is pivotally connected.

  As will be described later, the joint mechanism 4 is provided with centering means for aligning the axis of the rotary shaft 8 with the axis of the screw member on the workpiece side.

  That is, the pin 50 is formed so that the small diameter portion 50a is sandwiched between the large diameter portions 50b, and the small diameter portion 50a is inserted through the main body portion 53a of the second connecting member 53 (see FIG. 6). For this reason, the 2nd connection member 53 can move along the small diameter part 50a in the range latched by the large diameter part 50b. Further, a spring 55 is interposed between the support portions 52 b and 52 b of the first connecting member 52 and the main body portion 53 a of the second connecting member 53. The second connecting member 53 is urged by these springs 55 and 55 and is normally located at the center between the two support portions 52 b and 52 b of the first connecting member 52.

  On the other hand, between the second connecting member 53 and the third connecting member 54, the same structure (not shown) is adopted so that the third connecting member 54 can be moved along the pin 51. It is. That is, since the third connecting member 54 is connected to the first connecting member 52 in a state in which the third connecting member 54 is movable in two orthogonal directions, the rotary shaft 8 is misaligned with respect to the output shaft of the bearing mechanism 3. Also, the power transmission from the bearing mechanism 3 to the rotating shaft 8 is performed smoothly.

  Stopper bolts 56 that are in contact with the main body 52a of the first connecting member 52 and restrict the rotation of the second connecting member 53 around the rotation shaft 50 are planted at both ends of the locking portion 53c of the second connecting member 53. It is installed. On the other hand, at both ends of the main body portion 54 a of the third connecting member 54, stopper bolts 57 that abut the locking portions 53 b of the second connecting member 53 and restrict the rotation of the third connecting member 54 around the rotation shaft 51. Has been planted.

  FIG. 7 is a cross-sectional perspective view showing the support structure of the rotating shaft 8.

  The rotating shaft 8 includes a drive unit 80 housed in the housing 4a of the joint mechanism 4 and a main body 81 that protrudes from the housing 4a of the joint mechanism 4 to the outside. In the drive unit 80, the base end flange 82 is screwed to the main body 54 a of the third connecting member 54. A spline portion 82a having a substantially square cross section is formed in the drive portion 80 from the intermediate portion to the tip. The rotating shaft 8 is configured to be extendable and retractable by fitting the spline portion 82 a of the driving portion 80 into the hole 83 of the main body portion 81.

  A taper portion 84 is formed at the base end portion of the main body portion 81. The tapered portion 84 is urged by a spring 85 interposed between the flange 82 of the driving portion 80 and pressed against the bearing portion 86 of the housing 4a. A socket portion 87 as an engaging portion is formed at the tip of the main body portion 81, and a magnet 88 for attracting and holding the bolt B is embedded in the socket portion 87.

  FIG. 9 shows a bolt supply device for the screw member fastening device 1.

  The bolt B is conveyed to the turntable 101 side on the parts feeder 100 with the head h facing upward. Four chuck devices 102 are installed on the turntable 101. The bolts B are gripped by the chuck 104 of the bolt transfer device 103 and are sequentially transferred from the parts feeder 100 to the chuck device 102 on the turntable 101. The turntable 101 is configured to be movable up and down, and can be lifted up to a position where the bolt B protrudes from the hole 106 of the plate 105 disposed above the turntable 101.

  The plate 105 is provided with an opening means 107 for opening the chuck mechanism 27 of the screw member fastening device 1. The opening means 107 is formed by installing a pair of rollers 109 at the tip of the output rod 108a of the actuator 108, and is disposed at each of the positions where the hole 106 of the plate 105 is equally divided into four. When the actuator 108 is actuated, the output rod 108a protrudes toward the inside of the hole 106, and the roller 109 provided at the tip of the output rod 108a contacts the cam portion 29a of the claw member 29 to open the claw member 29. (See FIG. 10).

  Next, the operation of the screw member fastening device 1 of the present embodiment will be described.

  The screw member fastening device 1 is attached to the tip of an articulated movable arm, and is used for, for example, a bolt fastening operation when attaching a side door of an automobile to a vehicle body.

  When supplying the bolt B to the bolt holding means 20, the rotary drive unit 5 is retracted to the starting position shown in FIG. 1 in advance and the tip of the rotary shaft 8 is brought out of the cylindrical portion 28 c of the chuck body 28. deep. First, the screw member fastening device 1 is lowered from above the bolt supply device of FIG. 9, and the tip of the chuck mechanism 27 is inserted into the hole 106 of the plate 105. Next, the output rod 108 a of the actuator 108 is advanced, and the roller 109 is pressed against the cam portion 29 a of the claw member 29 to open the claw member 29.

  In this state, the turntable 101 is raised to allow the bolt B to enter the chuck mechanism 27 (see FIG. 10). Next, the output rod 108 a of the actuator 108 is retracted, the pressing of the cam portion 29 a by the roller 109 is released, and the claw member 29 is closed. At this time, the circumferential groove 29b of the claw member 29 engages with the flange portion f of the bolt B, and the claw member 29 clamps the bolt B (see FIG. 4A).

  The screw member fastening device 1 moves to the teaching position on the workpiece side in a state where the four bolts B are held as described above, and the rotary shaft 8 among the four bolts B held by the bolt holding means 20. The tip of the bolt B on the extension line is made to face the nut N on the workpiece side. Next, the stepping motor 12 is activated to advance the rotary drive unit 5 so that the tip of the rotary shaft 8 enters the cylindrical portion 28c of the chuck body 28 while slowly rotating the rotary shaft 8 in the reverse direction. The socket part 87 is engaged with the head h of the bolt B (see FIG. 4B). When the socket part 87 is engaged with the bolt B, the spline part 82a of the drive part 81 is pushed into the hole 83 of the main body part 81 of the rotary shaft 8, so that the rotary shaft 8 starts to contract.

  When the rotary drive unit 5 further advances, the pair of rollers 34, 34 ride on the cam portions 29 a, 29 a of the claw members 29, 29 to open the claw members 29, 29. At this position, the rotary drive unit 5 is stopped. At this time, since the holding of the bolt B by the claw members 29 and 29 is released, the main body portion 81 of the rotating shaft 8 is pushed out to the workpiece side by the spring 85, and the tip of the bolt B attached to the socket portion 87 is the workpiece. Engage the side nut N. At this time, since the rotary shaft 8 has a slight gap between the taper portion 84 of the main body 81 and the bearing portion 86 of the housing 4a, the rotary shaft 8 is swung or centered by the joint means 4 as described later. Operation will be allowed. The reason why the bolt B is gently reversely rotated at this stage is to improve the engagement of the bolt B with the nut N.

  Next, the rotating shaft 8 is rotated in the positive direction at a normal speed, and the bolt B is tightened. Even when the tightening of the bolt B is finished, the rotating shaft 8 is maintained in a floating state by securing a slight gap between the tapered portion 84 of the rotating shaft 8 and the bearing portion 86. When the tightening of the bolt B is completed, the rotary drive unit 5 is temporarily retracted to the starting position, the rotating member 22 is rotated 90 degrees, and the other bolt B held by the chuck mechanism 27 is disposed on the extension line of the rotating shaft 8. The In this state, the same operation is repeated.

  In addition, regarding the tightening of the bolt B, the following may be performed separately from the above method.

  That is, when the teaching position of the workpiece is set at a position away from the actual position of the workpiece and the holding of the bolt B by the claw members 29, 29 is released, the tip of the bolt B is the nut N on the workpiece side. The state is not reached. Thereafter, the entire screw member tightening device 1 is moved, the tip of the bolt B is pressed against the nut N on the workpiece side, the rotary shaft 8 is brought into a floating state as described above, and the bolt B is tightened in the same manner as described above. Do.

  By the way, when the screw member tightening device 1 is moved to the teaching position by the articulated movable arm, the bolt B and the workpiece side nut at the standby position on the extension line of the rotary shaft 8 as shown in FIG. The N axis may be misaligned. In this case, assuming that the joint mechanism 4 is a mere universal joint, the tip of the rotating shaft 8 swings around the pins 50 and 51, and the bolt B is screwed obliquely into the nut N on the workpiece side. (See (B) in the figure). In this case, it becomes a cause that the thread rises.

  On the other hand, when the joint mechanism 4 provided with the centering means described above is used, the rotary shaft 8 moves in two directions orthogonal to each other as the rotary shaft 8 rotates, and the axis of the rotary shaft 8 is the workpiece. It coincides with the axis of the nut N on the side (see FIG. 4C). As a result, the inclination of the bolt B is corrected, and the bolt B is screwed in in a normal posture, so that no thread rise occurs.

  Furthermore, in this screw member fastening device 1, the taper portion 84 of the main body portion 81 of the rotating shaft 8 is pressed against the bearing portion 86 of the housing 4a by a spring 85, whereby the rotating shaft 8 is swung or centered by the joint means 4. Therefore, the bearing structure of the rotary shaft 8 is simplified, which is advantageous in terms of cost.

  Further, since the joint mechanism 4 is configured so that the rotation range of the second connecting member 53 and the third connecting member 54 can be adjusted by the stopper bolts 56 and 57, the shaft center misalignment between the rotary shaft 8 and the workpiece side nut N is prevented. The stopper bolts 56 and 57 may be adjusted in consideration of the assumed range. For this reason, unnecessary swinging of the rotating shaft 8 can be suppressed and durability of the bearing portion can be improved.

  By the way, when the side door of the automobile is assembled to the vehicle body, the pair of upper and lower door hinges are fixed with two bolts B, respectively, so that four bolts B in total are required for one work. Therefore, by setting the number of the chuck mechanisms 27 of the bolt holding means 20 to four, the number of bolts B necessary for the work of one work is supplied to the bolt holding means 20 from the bolt supply device. Furthermore, it is not necessary to provide a mechanism for opening the chuck mechanism 27 in the bolt holding means 20. For this reason, the bolt holding means 20 can be made compact regardless of the size of the bolt B to be used, and versatility is improved.

  Further, the chuck mechanism 27 pivotally couples the base end portions of the pair of claw members 29, 29 to the chuck main bodies 28a, 28b with the pins 31, and cam portions 29a, 29a to the base end portions of the claw members 29, 29. Since the spring 32 is disposed on the back side of the cam portions 29a, 29a, the bolt B can be held and released by a simple mechanism. Also, the delivery of the bolt B from the chuck mechanism 27 to the rotating shaft 8 and the delivery of the bolt B from the chuck device 102 on the supply device side to the chuck mechanism 27 can be realized by a simple mechanism.

  Furthermore, a pair of rollers 109 is provided at the tip of the output rod 108a of the actuator 108, and the rollers 109, 109 are pressed against the cam portions 29a, 29a of the adjacent claw members 29, 29 to open the claw members 29, 29. Therefore (see FIG. 10), the number of parts can be omitted and the cost can be reduced.

The perspective view which shows the whole screw member fastening apparatus of this invention. The figure which expands and shows the bolt holding means of FIG. The figure which looked at the bolt holding means of FIG. 2 from the back side. Sectional drawing which shows the holding | maintenance state of the volt | bolt by the nail | claw member of FIG. The enlarged view which cuts and shows the housing of the reduction gear and coupling mechanism of FIG. The figure explaining operation | movement of a coupling mechanism. The cross-sectional perspective view which shows the support structure of a rotating shaft. The figure explaining the tightening state of a volt | bolt. The perspective view which shows the supply apparatus of the volt | bolt with respect to the screw member fastening apparatus of this invention. The perspective view which shows the state which delivers a volt | bolt from the volt | bolt supply apparatus of FIG. 9 to the volt | bolt holding means of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Screw member fastening apparatus 2 Motor 3 Reduction gear 4 Joint mechanism 4a Housing 5 Rotation drive unit 8 Rotating shaft 20 Bolt holding means 22 Rotating member 25 Motor 27 Chuck mechanism 28 Chuck body 29 Claw member 29a Cam part 29b Circumferential groove 29c Hole 31 Pin 32 Spring 102 Chuck device 87 Socket part B Bolt N Nut

Claims (1)

A screw member tightening means for attaching a screw member to an engaging portion at the tip of the rotating shaft connected to the driving means, moving the rotating shaft to the work side and screwing the screw member into the screw portion of the work, and the screw member In a screw member supply tightening device comprising screw member supply means for supplying the screw member to the tightening means,
A rotating member having a plurality of chuck mechanisms for holding the screw member is provided in the screw member tightening means, and when the rotating shaft is moved to the workpiece side, the engaging portion engages with the screw member. Screw member holding means for step-rotating the rotating member so that the chuck mechanisms are sequentially stopped at a position where the screw member is transferred to the rotating shaft;
A screw member supply preparing means which is provided in the screw member supply means and holds the screw member in a state where it can be delivered to each chuck mechanism of the screw member holding means;
A screw member supply and tightening device comprising:

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