JP2011125958A - Chuck device and robot arm - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chuck device capable of improving the carrying efficiency of work. <P>SOLUTION: The chuck device 1 is equipped with chuck portions 10-50. In a chuck portion 10, a supporting plate 12 for supporting three chucks 11 is coupled to a gear 14 by a coupling member 13. The supporting plate 12 is supported by a side plate 62 so as to vertically move in a Y-direction. When a gear 87 is rotated by rotations of a gear 82 on a drive side, rotation movement is converted to linear movement by the coupling member 13 which is a crank mechanism to vertically reciprocate the supporting plate 12, and vertically move the chucks 11. The chuck portions 20-50 are similar. The chuck device 1 is constituted to generate deviation at a position in a reciprocating direction of the chuck portions adjacent to each other. For example, if the chuck portion 20 moves forward, the next chuck portion 10 moves backward. Therefore, even if intervals between the chuck portions adjacent to each other are not expanded, the carrying efficiency of the work can be improved by increasing a number of the chucks. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a chuck device attached to a robot arm and a robot arm.

  In the manufacturing process, it is necessary to perform an operation of transporting a work such as a part to be assembled from one position to another position. For example, in a multi-variety variable-volume production site, a chuck device having a large number of chucks is attached to the tip of a robot arm of a multi-axis robot, and the robot arm is moved while holding a workpiece with each chuck. In this way, the workpiece is conveyed to a target position.

FIG. 8A is a diagram illustrating a configuration example in which a chuck device 902 including a plurality of chucks 903 to 905 is attached to the tip of the robot arm 901.
In the example of FIG. 8A, a state in which the chuck 905 tries to grip the workpiece 911 among the workpieces 911 to 913 placed on the workpiece supply table 910 is illustrated. In this case, the posture of the chuck device 902 is changed by the operation of the robot arm 901 so that the tip of the chuck 905 faces the direction in which the workpiece 911 is positioned.

When the posture of the chuck device 902 is changed, the chuck device 902 is lowered toward the workpiece 911 by the robot arm 901, and when the chuck 905 reaches the workpiece 911, the workpiece 911 is gripped by the chuck 905.
When the workpiece 911 is gripped by the chuck 905, the chuck device 902 is once separated from the workpiece supply base 910, and the posture of the chuck device 902 is adjusted by the robot arm 901 so that the tip of the chuck 904 faces the direction in which the workpiece 912 is positioned. Be changed.

When the posture of the chuck device 902 is changed, the chuck device 902 is lowered toward the workpiece 912 and the workpiece 912 is gripped by the chuck 904.
Thereafter, the chuck device 902 moves away from the workpiece supply table 910 again while the workpieces 911 and 912 are held by the chucks 905 and 904. When the posture of the chuck device 902 is changed by the robot arm 901 so that the tip of the chuck 903 faces the direction in which the workpiece 913 is positioned, the chuck device 902 is lowered toward the workpiece 913, and the workpiece 913 is moved by the chuck 903. Grasped.

When the workpieces 911 to 913 are gripped, the robot arm 901 performs an operation such as reversal, and the workpieces 911 to 913 are transported toward the target position (the right end portion in FIG. 8A).
A large number of workpieces can be transported by performing the operation for moving the robot arm 901 from the workpiece supply table to the target position only once, and the workpiece transport efficiency is improved.

Robot No. 173, Japan Robot Industry Association, published in November 2006, p. 7-14

In order to further improve the work transfer efficiency, it is only necessary to increase the number of chucks provided in the chuck device.
However, in the configuration in which the number of chucks is simply increased, there is a possibility that a chuck out of a plurality of chucks that cannot grip the workpiece comes out.
That is, as shown in FIG. 8 (b), since a plurality of chucks 921, 922,... Are fixedly arranged in one housing 920, if the number of chucks is increased without changing the size of the housing 920. , The interval between adjacent chucks is narrowed.

If the interval between the chucks is narrowed, if the chuck 922 changes the posture of the housing 920 while gripping the workpiece 911 and then attempts to lower the chuck 922 toward the workpiece 912, the workpiece 911 that has already been gripped. This is because the work 912 cannot be gripped.
On the other hand, it is conceivable to make the interval between chucks as wide as possible, but if the interval between chucks is increased, the chuck device becomes longer in the direction in which the chucks are arranged as the number of chucks increases. Not realistic.

  An object of the present invention is to provide a chuck device and a robot arm that can further improve the work transfer efficiency.

  To achieve the above object, a chuck device according to the present invention includes a first chuck that is attached to a robot arm and can hold an object, and a second chuck that can hold an object different from the object held by the first chuck. A chuck device having a support means for supporting the first chuck so that the first chuck can be moved forward and backward, and a forward / backward movement for moving the first chuck supported by the support means so that the position in the forward / backward direction differs relative to the second chuck. Means.

The support means supports the second chuck so that the second chuck can advance and retract, and the advance / retreat means advances and retracts so that the second chuck moves backward when the first chuck moves forward.
Further, the first chuck is disposed substantially parallel to the second chuck, and the advance / retreat means has a first motor and a single motor for moving the second chuck back and forth.
Further, the advancing / retreating means is provided in each of the drive shaft that is rotated by the power from the motor, the first chuck, and the second chuck, and converts a plurality of rotations of the drive shaft into reciprocating motions of the first chuck and the second chuck, respectively. The conversion mechanism is further included.

Further, the conversion mechanism has a gear pair including a drive gear attached to the drive shaft and a driven gear meshed with the drive gear, and the gear pair of the conversion mechanism of the first chuck is such that the first chuck advances and retreats. The gear ratio between the drive gear and the driven gear is adjusted so as to deviate from the second chuck in the direction.
The conversion mechanism is a crank mechanism.

Further, the conversion mechanism may be a Scotch yoke mechanism.
In addition, the first chuck is adjacent to the second chuck.
Furthermore, the movement amount of the first chuck is the same as the movement amount of the second chuck.
Further, the first chuck may have a movement amount smaller than that of the second chuck.

  Further, the conversion mechanism is wound around the drive pulley attached to the drive shaft, the driven pulley provided corresponding to the drive pulley, the drive pulley and the driven pulley, and transmits the rotational force of the drive pulley to the driven pulley. A drive belt for converting the rotational movement of the driven pulley into a reciprocating movement, and the drive pulley and the driven pulley of the conversion mechanism of the first chuck are respectively arranged so that the first chuck is displaced from the second chuck in the advancing / retreating direction. The size of the diameter is adjusted.

  A robot arm according to the present invention includes the chuck device described above.

  If comprised as mentioned above, it will become possible to hold | grip a target object now without taking the space | interval of a 1st chuck | zipper and a 2nd chuck | zipper large, and the conveyance efficiency of a target object will be attained, without enlarging a chuck apparatus. Can be improved.

1 is a diagram illustrating an overall configuration of a chuck device according to Embodiment 1. FIG. It is the enlarged view which extracted and showed each part of the chuck apparatus partially. It is a schematic diagram which shows a mode that a shift | offset | difference arises in the position of each of five chucks. It is a graph which illustrates the relationship between the rotation angle and position for two chucks. It is a figure which shows the structural example using the Scotch yoke mechanism which concerns on Embodiment 2. FIG. It is a figure which shows another structural example using a belt drive mechanism. FIG. 10 is an overall configuration diagram illustrating a state where a chuck device is attached to a robot that can move on a two-dimensional plane according to a third embodiment. It is a figure which shows the structural example which attached the chuck device provided with the conventional several chuck | zipper to the front-end | tip of a robot arm.

Hereinafter, embodiments of a chuck device according to the present invention will be described with reference to the drawings.
<Embodiment 1>
1A and 1B are diagrams showing an overall configuration of a chuck device 1 according to the present embodiment, where FIG. 1A is a side view, and FIG. 1B is a cross-sectional view taken along line AA in FIG. . FIG. 2 shows a partially enlarged view of FIG. 1 and 2, the arrow X direction corresponds to the width direction, the Y direction corresponds to the height direction, and the Z direction corresponds to the depth direction. Hereinafter, the width direction may be referred to as the left-right direction and the height direction may be referred to as the up-down direction.

As shown in FIGS. 1 and 2, the chuck device 1 includes five chuck units 10, 20, 30, 40, 50, a base 60, a drive motor 70, a power transmission mechanism 80, and the like.
The base 60 includes a metal base 61 and side plates 62, 63, 64, and the like.
The base 61 is connected to the robot arm 2.
The side plates 62 to 64 are attached to the surface of the base 61 opposite to the connecting portion of the robot arm 2 in a posture parallel to each other with a space in the left-right direction.

The power transmission mechanism 80 includes a drive shaft 81, gears 82 to 91, and the like.
The drive shaft 81 penetrates the side plates 62, 63, 64 and is rotatably supported by the side plates 62, 62, 64.
The gears 82 and 87 are a gear pair provided corresponding to the chuck portion 10.
The gear 82 is fixed to the drive shaft 81.

The gear 87 is rotatably supported by a pin 141 provided on the side plate 62 and meshed with the gear 82.
The gears 83 and 88 are a gear pair provided corresponding to the chuck portion 20.
The gear 83 is fixed to the drive shaft 81.
The gear 88 is rotatably supported by a pin 241 provided on the side plate 62 and meshed with the gear 83.

The gears 84 and 89 are a gear pair provided corresponding to the chuck portion 30.
The gear 84 is fixed to the drive shaft 81.
The gear 89 is rotatably supported by a pin 341 provided on the side plate 63 and meshed with the gear 84.
The gears 85 and 90 are a gear pair provided corresponding to the chuck portion 40.

The gear 85 is fixed to the drive shaft 81.
The gear 90 is rotatably supported by a pin 441 provided on the side plate 63 and meshed with the gear 85.
The gears 86 and 91 are a gear pair provided corresponding to the chuck portion 50.
The gear 86 is fixed to the drive shaft 81.

The gear 91 is fixed to the rotation shaft 71 of the drive motor 70.
When the drive motor 70 rotates, the rotational driving force is transmitted to the gears 87 to 90 via the gear 91, the gear 86, the drive shaft 81, and the gears 82 to 85, and the gears 82 to 91 rotate simultaneously.
Driving force generated by the rotation of the gears 87 to 91 is transmitted to the chuck portions 10 to 50.
As shown in FIG. 1A, the chuck portion 10 includes three chucks 11, a support plate 12, a connecting member 13, and the like.

Each of the three chucks 11 is provided with a chuck claw 112 at the tip of an arm 111 and grips a workpiece by opening and closing the chuck claw (Jaw) 112.
As a mechanism for gripping the workpiece, for example, an electric type using a motor is used. The chuck 11, the drive motor 70, and the like are connected to a power cord (not shown) wired along the robot arm, and operate by power supplied through the power cord. The control of this operation is performed by a robot arm control unit (not shown) that controls the operation of the robot arm.

  The support plate 12 is a metal member that supports the base ends of the arms 111 of the three chucks 11. In the present embodiment, the three chucks 11 are arranged at intervals in the Z direction, and chucks positioned on both sides with respect to the axis of the arm 111 of the chuck 11 positioned in the center as shown in FIG. 11 The axis of each arm 111 forms an angle of about 45 °, and the three chucks 11 are fixed to the support plate 12 so that the distance between the front ends of the three chucks 11 is wider than the base end.

  Two guide pins 121 are provided on the surface of the support plate 12 facing the side plate 62 as shown in FIG. The two guide pins 121 are fitted into two guide grooves 621 provided on the side plate 62 and extending in the vertical direction. When the guide pin 121 is guided in the guide groove 621, the support plate 12 is supported so as to be movable in the vertical direction with respect to the side plate 62.

The connecting member 13 is a metal rod-like member, one end of which is rotatably supported by a shaft 131 provided on the support plate 12, and the other end of which is rotatably supported by a pin 132 provided on the main surface of the gear 87. It is supported. Further, the connecting member 13 constitutes a crank mechanism that converts the rotational movement of the gear 87 into the straight movement of the support plate 12 in the vertical direction.
In such a configuration, the rotational driving force by the drive motor 70 is transmitted to the gear 87 via the drive shaft 81 and the gear 82, and when the gear 82 and the gear 87 rotate in the direction of the arrow in FIG. The support plate 12 reciprocates in the vertical direction. As a result, the three chucks 11 are integrally reciprocated in the vertical direction.

The other chuck portions 20 to 50 have substantially the same configuration as the chuck portion 10.
That is, as shown in FIG. 2, the chuck unit 20 includes three chucks 21, a support plate 22, a connecting member 23, and the like. Two of the three chucks 21 are not shown. This is the same for the chuck portions 30 to 50.
The three chucks 21 are fixed to the support plate 22.

In the support plate 22, two guide pins 221 are fitted in guide grooves 622 provided in the side plate 62, and are supported by the side plate 62 so as to be movable in the vertical direction.
One end of the connecting member 23 is rotatably supported by a shaft 231 provided on the support plate 22, and the other end is rotatably supported by a pin 232 provided on the main surface of the gear 88.
When the gear 88 engaged with the gear 83 is rotated by the rotation of the gear 83, the rotational movement of the gear 88 is converted into the straight movement of the support plate 22 via the connecting member 23 constituting the crank mechanism. The reciprocating motion is performed in the vertical direction, and the three chucks 21 are integrally reciprocated in the vertical direction.

Similarly, the chuck unit 30 includes three chucks 31, a support plate 32, a connecting member 33, and the like. The three chucks 31 are fixed to the support plate 32.
In the support plate 32, two guide pins 321 are fitted in guide grooves 631 provided in the side plate 63, and are supported by the side plate 63 so as to be movable in the vertical direction.
One end of the connecting member 33 is rotatably supported by a shaft 331 provided on the support plate 32, and the other end is rotatably supported by a pin 332 provided on the main surface of the gear 89.

When the gear 89 meshed with the gear 84 is rotated by the rotation of the gear 84, the rotational movement of the gear 89 is converted into the straight movement of the support plate 32 through the connecting member 33, and the support plate 32 performs the reciprocating motion in the vertical direction. The three chucks 31 reciprocate in the vertical direction.
The chuck unit 40 includes three chucks 41, a support plate 42, a connecting member 43, and the like.
The three chucks 41 are fixed to the support plate 42.

In the support plate 42, two guide pins 421 are fitted in guide grooves 632 provided in the side plate 63, and are supported by the side plate 63 so as to be movable in the vertical direction.
One end of the connecting member 43 is rotatably supported by a shaft 431 provided on the support plate 42, and the other end is rotatably supported by a pin 432 provided on the main surface of the gear 90.
When the gear 90 meshed with the gear 85 is rotated by the rotation of the gear 85, the rotational movement of the gear 90 is converted to the straight movement of the support plate 42 via the connecting member 43, and the support plate 42 performs the reciprocating motion in the vertical direction. The three chucks 41 reciprocate in the vertical direction.

The chuck unit 50 includes three chucks 51, a support plate 52, a connecting member 53, and the like.
The three chucks 51 are fixed to the support plate 52.
In the support plate 52, two guide pins 521 are fitted in guide grooves 641 provided in the side plate 64, and are supported by the side plate 64 so as to be movable in the vertical direction.
The connecting member 53 has one end rotatably supported by a shaft 531 provided on the support plate 52 and the other end rotatably supported by a pin 532 provided on the main surface of the gear 91. When the gear 91 rotates, this rotational motion is converted into a linear motion of the support plate 52 through the connecting member 53, the support plate 52 reciprocates in the vertical direction, and the three chucks 51 reciprocate in the vertical direction.

In the present embodiment, the strokes (movement amounts) of the reciprocating motion are substantially the same for each of the chuck portions 10 to 50 (the connecting position of the connecting member and the gear is adjusted so that the strokes are substantially the same in each chuck portion). The movement direction is parallel.
As described above, the chuck units 10 to 50 are reciprocated simultaneously by the rotation of the drive motor 70.

The adjacent chuck portions are engaged with each other among the gears 82 to 91 so that the phases of the reciprocating motions are different from each other, and the positions of the chuck portions 10 to 50 in the reciprocating direction are shifted by the reciprocating motion of the chucks. Each gear ratio of the existing gear pair is adjusted in advance.
FIG. 3 is a schematic diagram illustrating a state in which the positions of the five chucks are displaced.

  In FIG. 3, the reference position indicates the position of the upper end in the vertical direction of the support plate when the reference chuck, for example, the chuck 11 is at the lowest point in the reciprocating stroke. Further, 0 °, α °, and β ° indicate rotation angles of the drive motor 70. The angle 0 ° is an angle when the reference chuck is at the reference position, and α ° and β ° are 0 °. Represents the rotation angle from. In addition, it is assumed that a workpiece (not shown) to be grasped is present at a position downstream of the chuck device in the Y direction.

When the rotation angle of the drive motor 70 is 0 °, among the chucks 11 to 51, the chucks 11 and 51 are at the lowest position in the vertical direction of FIG. 3, and the chucks 21, 31, and 41 are higher than the chucks 11 and 51. It is in a position (reference posture).
In the reference posture, it can be seen that at least two adjacent chuck portions are displaced in positions in the reciprocating direction (positions of adjacent chucks).

  On the other hand, when the rotation angle is α °, the chuck 21 is at the lowest position, and the other chucks 11 and 31 to 51 are positioned higher than the chuck 21 (attitude α), and the rotation angle is β °. In this case, the chuck 31 is at the lowest position, and the other chucks 11, 21, 41, 51 are positioned higher than the chuck 31 (attitude β). In the postures α and β, the positions of the adjacent chucks are shifted as in the reference posture.

Here, there is a relationship of rotation angle 0 ° <α ° <β °, and when the drive motor 70 is rotated from the reference posture (angle 0 °) and the rotation angle becomes α °, the posture α is obtained. The relationship between the rotation angle and the gear ratio is adjusted so as to be in the posture β when rotated by an angle of (β−α).
FIG. 4 is a graph illustrating the relationship between the rotation angle and the position for the chucks 11 and 21.
As shown in FIG. 4, the chuck 11 moves backward with respect to the workpiece when the angle is 0 ° to β °, and the chuck 21 moves with respect to the workpiece while the angle is 0 ° to α °. When the angle reaches α °, the lowest point is reached, and a backward movement is made between α ° and β °. Although the relationship with other chucks is not shown, reciprocation (advance and retreat) is performed so that a phase difference occurs between adjacent ones as in the relationship with chucks 11 and 21.

As described above, since the position of the adjacent chuck is shifted according to the magnitude of the rotation angle of the drive motor 70, the following effects can be obtained.
That is, for example, when the workpiece 11 is gripped by the chuck 11 in the reference posture and is changed to the posture α, the chuck 21 is moved backward while the posture is changed, so that the posture α is obtained.

When the posture α is reached, the chuck 21 comes out in a direction toward the workpiece rather than the chuck 11.
For this reason, in the posture α, even if the chuck 11 still holds the workpiece, the workpiece does not get in the way, and the chuck 21 can be used to hold another workpiece.
Further, when the posture α is changed to the posture β, the chucks 11 to 31 are moved to the posture β while the chucks 11 and 21 are moved backward while the chucks 31 and 21 are moved backward.

When the posture β is reached, the chuck 31 comes out in the direction toward the workpiece rather than the other chucks.
Therefore, in the posture β, even if both chucks 11 and 21 hold the workpiece, these workpieces do not interfere with the gripping of another workpiece by the other chuck, and the chuck 31 is used. Furthermore, it becomes possible to grip another workpiece. For other adjacent chucks, the same operation is performed by adjusting the gear ratio, so that the workpiece being gripped does not interfere with the gripping of another workpiece by the other chuck. Another workpiece can be gripped by a chuck that is not gripped.

Conventionally, since a plurality of chucks are fixed to the base, as shown in FIG. 8B, the workpiece 911 gripped by the chuck 921 becomes an obstacle, and the adjacent chuck 922 grips another workpiece. In order to increase the number of chucks, the distance between adjacent chucks has to be increased.
On the other hand, in this embodiment, since the position of the chucks in the reciprocating direction is provided, even if a chuck A grips a workpiece, the chuck A moves backward from the adjacent chuck B. If the chuck B is moved further forward than the chuck A, the chuck B can grip another workpiece while the workpiece gripped by the chuck A does not get in the way. Therefore, the number of chucks can be increased without increasing the distance between adjacent chucks.

In other words, if the chuck parts are configured so that the positions in the direction in which the chuck parts advance and retreat in the direction from the base 60 to the workpiece (advance and retreat direction) are shifted, the number of chucks can be increased without increasing the distance between adjacent chuck parts. It is possible to improve work transportability.
In addition, since the movement direction of the reciprocating motion is approximately parallel and the movement amount is the same for each chuck portion, the chuck support mechanism has the same configuration as compared to the configuration in which the movement direction and movement amount are individually different in each chuck portion. Can be used.

  The posture control of the chuck is executed by a robot arm control unit (hereinafter referred to as “control unit”). Specifically, the control unit associates in advance the rotation angle of the drive motor 70 and the posture of the chuck (posture α with respect to the rotational angle α °, posture β with respect to the rotational angle β °, etc.) A detection result of a detector such as a sensor for detecting that the reference chuck is located at the reference position is acquired. When the chuck posture is changed to a certain target posture, the rotation angle of the motor necessary for the transition to the posture α is read, and only the read rotation angle is obtained from the state where the reference chuck is at the reference position. The drive motor 70 is driven to rotate.

A program for performing the posture control is installed in the control unit together with a program for controlling the operation of the robot arm.
That is, when gripping a plurality of workpieces using the chucks 11 to 51, which workpiece is held by which chuck when the chuck is in any posture, and which posture is changed to which posture to hold the next workpiece How far the chuck device should be moved by the chuck is determined in advance based on the positional relationship on the coordinate axes of the robot arm and the workpiece.

  A program is created so that the robot arm moves as determined, and installed in the control unit. By performing such control, in this example, the robot arm can be transported from the workpiece mounting table to a target position by a single movement operation while holding a maximum of 15 workpieces. In the case of multi-variety variable-volume production, the number, size, shape, etc. of workpieces to be transferred change, so that the program is updated according to each case.

The posture of the chuck can be arbitrarily changed by adjusting the gear ratio.
For example, the reciprocating motion periods of the chuck portions 10 to 50 are made different from each other, and the chuck portions 10 to 50 are all located at the reference position at a specific rotation angle, and the rotation angles are varied, so that It is also possible to adopt a configuration in which the position of the matching chuck moves so as to shift.

3 and 4 schematically show how the positions of the chucks are shifted in the advancing and retracting directions, it goes without saying that this is only an example. For each production site, the gear ratio and the like are adjusted in advance so that the operation in the advance / retreat direction of each chuck suitable for the production site is executed.
In the above description, the gear ratio is adjusted as a method for causing a shift between adjacent chuck positions, but is not limited thereto. For example, the gear ratios of gear pairs (a pair of gears 82 and 87, a pair of gears 83 and 88, etc.) provided corresponding to each chuck portion may be the same. With this configuration, the reciprocating cycles of the chuck portions 10 to 50 are all the same. For example, if a phase difference of 72 ° is given to each other in the crank mechanism, the adjacent chuck portions correspond to 72 °. The reciprocating motion is performed in a state where the forward / backward movement (position with respect to the base 60) is shifted by the amount.

If the chuck portions 10, 30, 50 are set as one set A, the chuck portions 20, 40 are set as another set B, and the phase difference between the sets A and B is set to 180 °, one set of chuck portions is When advancing, the other set of chuck portions are in a retreating relationship, and the positions of adjacent chucks in the advancing / retreating direction can be shifted in time.
<Embodiment 2>
In the first embodiment, the gear drive mechanism is used. However, in this embodiment, a scotch yoke mechanism is used instead of the gear drive mechanism, and this point is different from the first embodiment. Hereinafter, in order to avoid duplication of description, description of the same contents as those in Embodiment 1 is omitted, and components having the same functions are denoted by the same reference numerals.

FIG. 5 is a diagram showing a configuration example using the scotch yoke mechanism according to the present embodiment.
As shown in FIG. 5, the chuck unit 600 includes a chuck 601, a support plate 602, a crankpin bearing 603, and the like.
The chuck 601 is the same as the chuck 11 and is supported by the support plate 602. Although only one is shown in FIG. 5, there may be a plurality such as three as shown in FIG.

The support plate 602 is fitted to the side plate 62 in the vertical direction by fitting the two guide pins 121 provided on the surface facing the side plate 62 into the two guide grooves 621 provided in the side plate 62 extending in the vertical direction. It is supported movably.
The crankpin bearing 603 has a disk shape, is fitted in a long hole 607 provided in the center of the support plate 602 and extending in the Z direction, and is eccentrically attached to the drive shaft 81.

When the drive shaft 81 is rotated by the drive motor 70, the crank pin bearing 603 is rotated so as to roll in the elongated hole 607 of the support plate 602, thereby causing the support plate 602 to reciprocate in the vertical direction. As a result, the chuck 601 moves back and forth in the vertical direction.
Although only one chuck portion 600 is shown in FIG. 5, as shown in FIG. 1B, five chuck portions 600 are arranged side by side in the X direction (left-right direction).

For each of the five chuck portions 600, the fixing position of the crank pin bearing 603 with respect to the drive shaft 81 is shifted in the circumferential direction, and the positions of adjacent chucks are shifted. By adopting the Scotch yoke mechanism, the number of gears in the drive mechanism can be reduced and the configuration of the entire apparatus can be further simplified.
As another example, a belt driving mechanism may be used.

FIG. 6 is a diagram illustrating an example of a belt driving mechanism.
As shown in FIG. 6, the chuck unit 700 includes a chuck 701, a support plate 702, a connecting member 703, and the like. The drive unit 710 as a belt transmission mechanism includes pulleys 711 and 712, a drive belt 713, and the like.
The chuck 701, the support plate 702, and the connecting member 703 have the same configuration as the chuck 11, the support plate 12, and the connecting member 13.

The pulley 712 is rotatably supported by the side plate 62, and the pulley 711 is fixed to the drive shaft 81. The drive belt 713 is wound around pulleys 711 and 712.
When the drive shaft 81 is rotated by the rotation of the drive motor 70, the rotational driving force is transmitted to the pulley 712 via the pulley 711 and the drive belt 713. When the pulley 712 rotates, the support plate 702 reciprocates in the vertical direction via the connecting member 703 constituting the crank mechanism, and the chuck 701 reciprocates in the vertical direction.

Since the pulley 711 on the driving side and the pulley 712 on the driven side are connected by the driving belt 713, the degree of freedom in design is increased as compared with a configuration in which the pulleys are connected by a gear.
In the example of FIG. 6, only one chuck portion 700 is shown. However, as shown in FIG. 1B, five chuck portions 700 are arranged at intervals in the left-right direction and correspond to each chuck portion 700. A drive unit 710 is provided. Since the period of movement of the chuck in the advancing / retreating direction is varied depending on the diameter of the pulleys 711 and 712, the diameters of the corresponding pulleys 711 and 712 with respect to each of the five chuck units 700 are determined in advance. The position is adjusted so that a shift occurs.

  Needless to say, the number of chuck portions is not limited to five. FIG. 6 shows a configuration example in which one chuck 701 is disposed in one chuck portion 700, but a configuration in which a plurality of chucks are disposed may be employed. Furthermore, a configuration may be adopted in which one chuck is disposed in a certain chuck portion and a plurality of chucks are disposed in another chuck portion. These are the same for the configuration examples in the above embodiments.

<Embodiment 3>
FIG. 7 is an overall configuration diagram showing a state where the chuck device 801 is attached to the robot arm 803 of the robot 802 that can move on a two-dimensional plane.
The chuck device 801 shown in FIG. 7 is basically the same as the chuck device 1 described above, but only one chuck 11 to 51 is provided in the chuck portions 10 to 50 (see FIG. 1B). A configuration example in which five workpieces can be conveyed by a total of five chucks 11 to 51 is shown.

  As shown in FIG. 7, the robot arm 803 is movable along the XY direction. For example, when gripping five workpieces 811 to 815 placed on the workpiece placing table 810, the following is performed. The operation is performed. That is, for example, when the workpieces 811 to 815 are gripped in the order of the chucks 11 to 51, the drive motor 70 is driven to change the posture of the chuck to the chuck 11 (specifically, the reference posture). The robot arm 803 is moved while shifting so that the workpiece 811 is gripped by the chuck 11.

While holding the workpiece 811 with the chuck 11, the robot arm 803 is once separated from the workpiece mounting table 810, and then the drive motor 70 is driven so that the chuck 21 is used when the chuck 21 is used (specifically, In this case, the robot arm 803 is moved while changing to the posture α), and the workpiece 812 is gripped by the chuck 21.
While holding the workpieces 811 and 812 with the chucks 11 and 21, the robot arm 803 is moved away from the workpiece mounting table 810, and the drive motor 70 is driven to change the posture of the chuck 31 to be used (specifically, In this case, the robot arm 803 is moved while changing to the posture β), and the workpiece 813 is gripped by the chuck 31.

Similarly, the robot arm 803 is moved away from the workpiece mounting table 810 while holding the workpieces 811 to 813 with the chucks 11 to 31. The drive arm 70 is driven to change the posture of the chuck to the posture when the chuck 41 is used, and the robot arm 803 is moved to grip the workpiece 814 with the chuck 41.
Finally, while holding the workpieces 811 to 814 with the chucks 11 to 41, the robot arm 803 is moved away from the workpiece mounting table 810 and the drive motor 70 is driven to change the posture of the chuck to the posture when the chuck 51 is used. While making the transition, the robot arm 803 is moved and the workpiece 815 is gripped by the chuck 51.

When the five workpieces 811 to 815 are gripped, the robot arm 803 is moved along the X direction and the Y direction as indicated by arrows (broken lines) to the workpiece assembly target 820 at the target position, and heads toward the assembly target 820. .
When arriving at the assembly target 820, the robot 802 is operated in the same manner as when the workpiece is gripped. That is, for each of the workpieces, while changing the posture of the robot arm 803 so that the chuck holding the workpiece is in a position suitable for assembly, for example, in a state of being advanced more than the other chucks, After the chuck device 801 is moved closer to the assembly target 820 by the movement and the work is mounted on the assembly target 820 such as placing the workpiece at a predetermined position or fitting into a predetermined part, the assembly is performed. The operation of once leaving the object 820 is repeated in a predetermined order.

As described above, by using the chuck device 801 for a linear motion robot having a simpler configuration than that of the multi-axis robot, the linear motion robot can be multi-functional.
(Modification)
As described above, the present invention has been described based on the embodiment. However, the present invention is not limited to the above-described embodiment, and the following modifications may be considered.

(1) In the first embodiment, the crank mechanism or the like is used as the mechanism for changing the rotational motion to the linear motion. However, the present invention is not limited to this. For example, a configuration in which linear reciprocating drive is performed by a rack and pinion type mechanism may be employed.
(2) In the first embodiment described above, the configuration example in which three chucks are arranged in one chuck portion and the three chucks are fixed to one support plate has been described. However, the present invention is not limited to this.

For example, a configuration may be adopted in which each chuck is supported so as to be able to advance and retract in the direction relative to the workpiece so that the positions of adjacent chucks in one chuck portion are displaced. This corresponds to a configuration in which each of the five chucks shown in FIG.
Moreover, although the example of a structure which each chuck | zipper performs a linear reciprocating motion was demonstrated, it is not restricted to this. For example, the structure which reciprocates along a curve may be sufficient. Further, the round trip does not have to follow the same route, and for example, the forward path and the return path may have different configurations.

(3) In the above embodiment, the amount of movement of each chuck in the advancing / retreating direction is the same for each chuck, but a difference may be made in the amount of movement. For example, when the chuck B grips a short workpiece while the chuck A grips a workpiece that is long in the advancing / retreating direction, it is assumed that the long workpiece is an obstacle if the stroke is the same.
In such a case, if the movement amount of the chuck B is set larger than that of the chuck A, the chuck B can be brought closer to the work by the larger movement amount, and the work held by the chuck A is obstructed. It becomes possible for the chuck B to grip the work without becoming.

(4) In Embodiment 1 described above, the number of motors is reduced by using a configuration in which one drive motor 70 is shared and the rotational driving force is distributed to a plurality of chuck portions. For example, a motor may be provided independently for each chuck portion.
If comprised in this way, only the chuck | zipper which should be used for the holding | grip of a workpiece | work will be advanced to a full direction in the advancing / retreating direction, and it will take the attitude | position which retracts another chuck | zipper to the full, and the workpiece | work already gripped by the other chuck | zipper The workpiece can be gripped by using the chuck that has been advanced to the full extent so as not to get in the way. A motor, a gear, a connecting member, etc. provided in each chuck portion constitute driving means for driving each chuck so that the chuck is displaced.

Moreover, it is not restricted to the structure using the drive motor 70 which outputs a rotational drive force, For example, what is called a linear motion motor which advances / retreats an output shaft can also be used. If a linear motor is used, a crank mechanism that converts rotational motion into linear motion becomes unnecessary, and the configuration can be simplified.
Furthermore, it is not limited to a motor. Any device that outputs a driving force for advancing and retracting the plurality of chucks in the direction from the base 60 toward the workpiece may be used. For example, an actuator other than a motor, specifically, a solenoid or a hydraulic cylinder may be used.

(5) In the above embodiment, the configuration example in which the movement directions of the chuck units 10 to 50 in the reciprocating operation are substantially parallel has been described. However, the plurality of chuck units advance and retreat in the direction from the base 60 toward the workpiece. As long as the configuration is freely supported, the configuration is not limited to being parallel.
For example, two chuck parts are arranged so that the tip side opens like a fan, and the forward and backward movement of each chuck part is executed in a direction in which the forward direction of one chuck part and the forward direction of the other chuck part do not intersect It is conceivable to adopt a configuration such as With this configuration, as the chuck A advances, the distance between the chuck claw on the tip side of the chuck A and the adjacent chuck B increases, and the chuck A grips the workpiece. It becomes more difficult for a workpiece already gripped by the adjacent chuck B to interfere with gripping.

  (6) Needless to say, the shape, size, material, etc. of the members such as the chuck, the support plate, and the base in the above embodiment are not limited to those described above. Appropriate shape, size, material, etc. are determined according to the above. In addition, although the five chuck portions 10 to 50 are provided, the present invention is not limited to this, and a plurality of chuck portions may be used. Further, the configuration example in which the posture of the chuck is controlled by the robot arm control unit has been described, but a control unit different from the control unit that controls the operation of the robot arm may be in charge.

  Furthermore, in the above-described embodiment, the adjacent chuck portions are configured such that the positions in the advancing and retreating directions are shifted, but the present invention is not limited to the adjacent ones. What is necessary is just to be comprised so that the position in an advancing / retreating direction may shift | deviate relatively at least 2 chuck | zipper parts. For example, among the plurality of chucks, a configuration in which one chuck is fixed to the base and another chuck is movable back and forth with respect to the base is also included. Moreover, although the structural example using what hold | grips a workpiece | work as a chuck | zipper was demonstrated, it is not restricted to this. Any chuck can be used as long as it can hold a workpiece. For example, a chuck that holds a workpiece by suction is also included in the chuck.

  The contents of the above embodiment and the above modification may be combined.

  The present invention can be widely applied to a chuck device including a plurality of chucks for gripping a workpiece.

DESCRIPTION OF SYMBOLS 1,801 Chuck apparatus 2,803 Robot arm 10, 20, 30, 40, 50, 600, 700 Chuck part 11, 21, 31, 41, 51, 601, 701 Chuck 12, 22, 32, 42, 52, 602 , 702 Support plate 13, 23, 33, 43, 53, 703 Connecting member 60 Base 61 Base 62, 63, 64 Side plate 70 Drive motor 80 Power transmission mechanism 81 Drive shaft 82-91 Gear 121, 221, 321, 421 521 Guide pin 603 Crank pin bearing 607 Long hole 621, 622, 631, 632, 641 Guide groove 710 Drive unit 711, 712 Pulley 713 Drive belt

Claims (12)

A chuck device having a first chuck attached to a robot arm and capable of holding an object, and a second chuck capable of holding an object different from the object held by the first chuck,
A support means for supporting the first chuck so as to freely advance and retract;
Advance / retreat means for advancing / retreating the first chuck supported by the support means so that the position in the advance / retreat direction is different relative to the second chuck;
A chuck apparatus comprising: The support means supports the second chuck so as to advance and retreat,
The advance / retreat means advances / retreats so that the second chuck moves backward when the first chuck moves forward,
The chuck device according to claim 1. The first chuck is disposed substantially parallel to the second chuck;
The advance / retreat means has one motor for advancing / retreating the first chuck and the second chuck,
The chuck device according to claim 1 or 2. The advance / retreat means is:
A drive shaft that is rotated by power from the motor;
A plurality of conversion mechanisms provided on the first chuck and the second chuck, respectively, for converting the rotational motion of the drive shaft into the reciprocating motion of the first chuck and the second chuck, respectively;
The chuck device according to claim 3. The conversion mechanism has a gear pair composed of a drive gear attached to the drive shaft and a driven gear meshed with the drive gear,
The gear pair of the conversion mechanism of the first chuck is adjusted in a gear ratio between the drive gear and the driven gear so that the first chuck is displaced from the second chuck in the forward / backward direction,
The chuck device according to claim 4. The conversion mechanism is a crank mechanism;
The chuck device according to claim 4 or 5. The conversion mechanism is a Scotch yoke mechanism.
The chuck device according to claim 4 or 5. The first chuck is adjacent to the second chuck;
The chuck device according to claim 1. The movement amount of the first chuck is the same as the movement amount of the second chuck.
The chuck device according to claim 1. The movement amount of the first chuck is smaller than the movement amount of the second chuck.
The chuck device according to claim 1. The conversion mechanism is wound around a drive pulley attached to the drive shaft, a driven pulley provided corresponding to the drive pulley, the drive pulley and the driven pulley, and the rotational force of the drive pulley is applied to the conversion pulley. A drive belt that transmits to the driven pulley, and converts the rotational motion of the driven pulley into the reciprocating motion,
The diameters of the drive pulley and the driven pulley of the conversion mechanism of the first chuck are adjusted so that the first chuck is displaced from the second chuck in the forward / backward direction,
The chuck device according to claim 4.   A robot arm comprising the chuck device according to claim 1.

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