JP2015033751A - Gripping mechanism and workpiece moving mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gripping mechanism in which a rotation member 35 can be rotated to left and right without using a special actuator in a case that a work piece has an inclined part and which is light and inexpensive because the special actuator can be saved.SOLUTION: In a case that a second projection 37 is pushed downward by an external force as shown in Figure (a), a rotation member 35 is rotated clockwise on the figure with a rotation axis 36 as the center, since a first elastic member 55 is stretched and a second elastic member 57 is shrunk. When the external force disappears, the rotation member 35 is returned to the neutral position. In a case that a fourth projection 38 is pushed downward by an external force as shown in Figure (b), the rotation member 35 is rotated anti-clockwise on the figure with the rotation axis 36 as the center, since the first elastic member 55 is shrunk and the second elastic member 57 is stretched.

Description

  The present invention relates to a gripping mechanism that is attached to the tip of a robot and grips a work, and a work movement mechanism that includes the gripping mechanism.

A transfer robot is used to move the workpiece.
Since there are various forms of workpieces to be gripped, various forms of gripping mechanisms attached to the tip of the robot have been put into practical use (see, for example, Patent Document 1 (FIG. 8B)).

Patent document 1 is demonstrated based on the following figure.
FIG. 13 is a diagram for explaining the basic configuration of the conventional technique. A workpiece 100 indicated by a broken line has a tapered shape. The first claw 101 and the second claw 102 are supported by the redundant linear motion mechanism 103 and expand and contract as indicated by the arrow (1). Moreover, the 3rd nail | claw 104 and the 4th nail | claw 105 are supported by the drive mechanism 106, and expand / contract as shown by the arrow (2).

  According to the description of paragraph number [0020] in Patent Document 1, the redundant linear motion mechanism 103 is provided with two rotary electric motors. The drive mechanism 106 is provided with one rotary electric motor. Since the redundant linear motion mechanism 103 includes two rotary electric motors, the interval between the first claw 101 and the second claw 102 is arbitrarily set, and the tapered workpiece 100 can be gripped.

Incidentally, the gripping mechanism attached to the tip of the robot is required to be lighter. This is because the burden on the robot can be reduced.
In this regard, in Patent Document 1, three electric motors are indispensable, and since the electric motor incorporates a magnet and a coil, it is heavy and it is difficult to reduce the weight of the gripping mechanism.
Further, it is necessary to finely control the three electric motors, which increases the cost of creating a control circuit and increases the equipment cost of the gripping mechanism.

  Considering the further spread of the gripping mechanism attached to the tip of the robot, a gripping mechanism that is lighter in weight and inexpensive in equipment cost is required.

JP 2009-6460 A

  An object of the present invention is to provide a lighter and cheaper gripping mechanism.

The invention according to claim 1 is a gripping mechanism that is attached to the tip of a robot and grips a workpiece,
A bracket connected to the tip of the robot;
A fixed arm extending from the bracket;
A first claw and a third claw provided at a tip of the fixed arm and arranged at a predetermined interval in a direction perpendicular to the extending direction of the fixed arm;
A movable arm supported swingably on the bracket via a support shaft extending in a direction perpendicular to the extending direction of the fixed arm, and an actuator provided on the bracket for swinging the movable arm;
A rotating member attached to the tip of the movable arm so as to be rotatable up to a predetermined angle around the axis of the movable arm, and rotated by the pressing force of the workpiece;
The rotating member includes a second claw provided corresponding to the first claw and a fourth claw provided corresponding to the third claw.

  The invention according to claim 2 is characterized in that the actuator is an air cylinder unit.

  The invention according to claim 3 is characterized in that unevenness for preventing slipping is formed at the tips of the first to fourth claws.

The invention according to claim 4 is a workpiece moving device that includes the gripping mechanism according to any one of claims 1 to 3 and moves the workpiece.
The robot;
A main frame attached to the tip of this robot;
A first subframe extending perpendicularly from one end of the main frame and supporting the gripping mechanism;
A second subframe extending perpendicularly from the other end of the main frame;
And a pinching mechanism having a fifth claw and a sixth claw that are provided at the tip of the second subframe and sandwich the workpiece.

  In the invention according to claim 5, the second sub-frame is movably attached to the main frame, and the main frame is provided with a sub-frame moving mechanism for moving the second sub-frame closer to or away from the first sub-frame. Features.

  The invention according to claim 6 is characterized in that a rotary mechanism is interposed in the second subframe or a connecting member connecting the pinching mechanism to the second subframe, so that the pinching mechanism can be turned.

In the invention according to claim 1, since the distance between the third claw and the fourth claw can be changed with respect to the distance between the first claw and the second claw, the taper portion of the workpiece can be gripped.
Conventionally, three electric rotary motors have been provided. However, in the present invention, only one actuator can be used, the weight of the gripping mechanism can be reduced, complicated control is not required, and the equipment cost of the gripping mechanism is reduced. Can be greatly reduced.
Therefore, according to the present invention, a lighter and cheaper gripping mechanism is provided.

  In the invention according to claim 2, the actuator is an air cylinder unit. The air cylinder unit is inexpensive, easy to control, and provides a cheaper gripping mechanism.

  In the invention which concerns on Claim 3, the unevenness | corrugation for slipping is formed in the front-end | tip of the 1st-4th nail | claw. The output of the actuator can be small because there is no fear of the workpiece slipping. Small and lightweight actuators can be used.

According to a fourth aspect of the present invention, there is provided a workpiece moving device that includes the gripping mechanism according to any one of the first to third aspects of the present invention and that moves a workpiece, the first subframe including the gripping mechanism, and the first subframe. A pinching mechanism is provided in the second subframe arranged at a position away from the frame.
Since the workpiece is gripped by the gripping mechanism and the pinching mechanism that are arranged apart from each other, a long workpiece or a large workpiece can be moved. Even if a taper portion exists in a long workpiece or a large workpiece, the tapered portion can be gripped by a gripping mechanism. Therefore, it is possible to grip and move a workpiece having a complicated shape.

  In the invention according to claim 5, since the second sub-frame is provided with a sub-frame moving mechanism for moving the second sub-frame toward or away from the first sub-frame, it can be adjusted to the size and shape of the work, and the work has a more complicated shape. Can be gripped and moved.

  In the invention which concerns on Claim 6, since the pinching mechanism was made to turn, the workpiece | work of a still more complicated shape can be hold | gripped and moved.

It is a figure which shows the internal structure of the holding | grip mechanism which concerns on this invention. It is a front view of a holding | grip mechanism. FIG. 3 is a view taken in the direction of arrow 3 in FIG. 2. It is a single item figure of the 1st-4th nail | claw. FIG. 5 is a sectional view taken along line 5-5 of FIG. It is an effect | action figure of a rocking | fluctuation mechanism. It is an effect | action figure of a holding | grip mechanism. It is a front view of a workpiece moving mechanism provided with a gripping mechanism. FIG. 9 is a view taken in the direction of arrow 9 in FIG. 8. It is another Example figure of a workpiece | work moving mechanism. It is a disassembled perspective view of a rotary mechanism. It is an effect | action figure of a workpiece moving mechanism. It is a figure explaining the basic composition of the conventional technology.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

  As shown in FIG. 1, the gripping mechanism 10 includes a bracket 11, a fixed arm 20 that extends from the bracket 11, and a support shaft 31 that extends in a direction orthogonal to the extending direction of the fixed arm 20 (the front and back direction in the drawing). A movable arm 30 supported swingably on the bracket 11, an actuator 32 attached to the bracket 11, and a link 34 connecting the output shaft 33 of the actuator 32 and the base of the movable arm 30 are provided.

  When the output shaft 33 of the actuator 32 moves forward, the link 34 rotates counterclockwise in the drawing, and the movable arm 30 rotates about the support shaft 31 in the clockwise direction in the drawing. As a result, as indicated by an imaginary line, the tip of the movable arm 30 approaches the tip of the fixed arm 20.

  A bracket of the same shape (reference numeral 12 in FIG. 2) is placed on the bracket 11 and integrated with bolts 13 and 14. That is, the brackets 11 and 12 sandwich the actuator 32, the link 34, and the bases of the arms 20 and 30.

As shown in FIG. 2, since the actuator and the link are behind the bracket 12, the appearance is improved. A plurality of screw holes 15 are provided in the bracket 12.
An attachment 17 can be attached to the robot 16, and the gripping mechanism 10 can be connected to the attachment 17 with a bolt 18.

A bar 21 extending in a direction orthogonal to the fixed arm 20 (the front and back direction of the drawing) is fixed to the distal end of the fixed arm 20.
Further, a rotating member 35 extending in the front and back direction of the drawing is rotatably attached to the front end of the movable arm 30 by a rotating shaft 36. The movable arm 30 is provided with a swing mechanism 50. Details of the swing mechanism 50 will be described with reference to FIG.

  As shown in FIG. 3, the first claw 22 and the third claw 23 are attached to the bar 21 at a predetermined interval (pitch). The second claw 37 and the fourth claw 38 are attached to the rotating member 35. The second claw 37 corresponds to the first claw 22 and the fourth claw 38 is arranged corresponding to the third claw 23.

  As shown in FIG. 4, the first claw 22 has a rod-shaped screw 42 with a male screw 41 cut on the outer periphery, the tip of which is processed into a truncated cone shape, and a recess formed in the truncated cone. . As a result, the first claw 22 includes a concave portion 43 and a convex portion 44 at the tip. The concave portion 43 and the convex portion 44 increase the coefficient of friction with the workpiece and exhibit an anti-slip action. The same applies to the second to fourth claws 23, 37, and 38.

  As shown in FIG. 5, the swing mechanism 50 includes a first fixed side plate 51 and a second fixed side plate 52 extending from the movable arm 30 to the left and right, and a rotating member 35 indicated by an imaginary line extending to the back of the drawing. 1st movable side plate 53 and 2nd movable side plate 54, 1st elastic member 55 arrange | positioned between 1st fixed side plate 51 and 1st movable side plate 53, 1st fixed side plate 51, and 1st movable side A first bolt 56 passed to the side plate 53, a second elastic member 57 disposed between the second fixed side plate 52 and the second movable side plate 54, the second fixed side plate 52 and the second movable side. It consists of a second bolt 58 delivered to the plate 54.

The first and second elastic members 55 and 57 are preferably compression coil springs, but may be leaf springs or torsion springs.
In addition, the first and second bolts 56 and 58 are not tightened in the neutral state of FIG. Therefore, the neutral state is maintained by the repulsive force of the first and second elastic members 55 and 57.

  As shown in FIG. 6A, when the second claw 37 is pushed downward by an external force, the first elastic member 55 is extended and the second elastic member 57 is contracted, so that the rotating member 35 is rotated. Rotate around the drawing 36 clockwise. The rotation angle θ is, for example, 10 °. At 10 °, the first fixed side plate 51 and the first movable side plate 53 are restricted from being further separated by the first bolt 56. When the external force disappears, the process returns to FIG.

  As shown in FIG. 6B, when the fourth claw 38 is pushed downward by an external force, the first elastic member 55 is contracted and the second elastic member 57 is extended, so that the rotating member 35 is rotated. Rotate counterclockwise around 36. The rotation angle θ is, for example, 10 °. At 10 °, the second fixed side plate 52 and the second movable side plate 54 are restricted from being further separated by the second bolt 58. When the external force disappears, the process returns to FIG.

  The preferred example of the swinging mechanism 50 has been described with reference to FIG. 5, but any swinging mechanism 50 may be used as long as it can swing left and right by about 10 ° and can be made almost neutral when there is no external force. is there. However, those using a driving means such as a rotary actuator or a cylinder for the rotational operation are excluded from the present invention.

The operation of the gripping mechanism 10 described above will be described next.
As shown in FIG. 7A, the workpiece 60 that is the object to be gripped has a grip thickness t1 at the first grip portion 61, and a grip thickness at the second grip portion 62 is t2 larger than t1. It is. The bar 21 is placed on one side of the work 60 and the rotating member 35 is placed on the other side. Next, the rotating member 35 is brought close to the bar 21.
As shown in FIG. 7B, the rotating member 35 rotates so as to follow the shape of the workpiece 60. As a result, the tapered workpiece 60 can be sandwiched between the first claw 22 and the second claw 37 and can be sandwiched between the third claw 23 and the fourth claw 38.

A workpiece 60 having a more complicated shape is shown in FIG.
Even the workpiece 60 </ b> B can be sandwiched between the first claw 22 and the second claw 37 and can be sandwiched between the third claw 23 and the fourth claw 38.

Next, the workpiece moving mechanism 70 including the gripping mechanism 10 of the present invention will be described.
As shown in FIG. 8, the workpiece moving mechanism 70 includes a robot 16, a main frame 71 attached to the tip of the robot 16, and a first subframe that extends perpendicularly from one end of the main frame 71 and supports the gripping mechanism 10. 72, a second subframe 73 extending perpendicularly from the other end of the main frame 71, a connecting member 74 provided at the tip of the second subframe 73, and a pinching mechanism 75 provided at the tip of the connecting member 74, Consists of. Details of the pinching mechanism 75 will be described with reference to FIG.

Further, a slider 76 is provided on the main frame 71, and the second subframe 73 is attached to the slider 76. The second sub frame 73 is attached to the main frame 71 so as to be movable.
The main frame 71 includes a subframe moving mechanism 77 that moves the second subframe 73 closer to or away from the first subframe 72. The sub-frame moving mechanism 77 is preferably a servo cylinder or a stepping cylinder whose position can be controlled.

  As shown in FIG. 9, the pinching mechanism 75 is a so-called crab pinching mechanism, and the first and second fingers 81, 82 swing on the connecting member 74 via pins 78, 78 in the opening / closing direction. The first finger 81 is provided with a fifth claw 83, and the second finger 82 is provided with a sixth claw 84. The first and second fingers 81 and 82 are opened and closed by an actuator (not shown).

Next, an example of changing the workpiece moving mechanism 70 described with reference to FIG. 8 will be described.
As shown in FIG. 10, in the workpiece moving mechanism 70 </ b> B, a rotary mechanism 90 is interposed in the connecting member 74. Since the other parts are the same as those in FIG. 8, the reference numerals are used, and detailed description thereof is omitted. The rotary mechanism 90 can also be interposed in the second subframe 73.

As shown in FIG. 11, the rotary mechanism 90 includes an upper disk 91, a lower disk 92, a rod 93 that rotatably connects the upper and lower disks 91, 92, and a torsion spring that passes to the upper disk 91 and the lower disk 92. 94.
When a rotational force is applied to the lower disk 92 from the outside, the lower disk 92 rotates with respect to the upper disk 91. When the rotational force from the outside disappears, the lower torsion spring 94 returns to the original position by the return action of the torsion spring 94.

As shown in FIG. 12A, the workpiece 60 </ b> C has a sufficiently large and complicated shape, and includes, for example, a taber-like flange portion 64 and an oblique overhang 65.
The first claw 22 and the third claw 23 are placed on one side of the taber-shaped flange portion 64, the second claw 37 and the fourth claw 38 are placed on the other side, and the fifth claw 83 and the other side are placed on one side of the overhang 65. 6th nail 84 is put on.
The second claw 37 is brought closer to the first claw 22, the fourth claw 38 is brought closer to the third claw 23, and the fifth and sixth claws 83, 84 are brought closer to each other.

  As a result, as shown in FIG. 12B, the flange portion 64 can be gripped by the first to fourth claws 22, 23, 37, and 38, and the overhang 65 can be gripped by the fifth and sixth claws 83 and 84. it can. In particular, since the pinching mechanism 75 is pivotable, the gripping is performed smoothly even if the inclination angle of the overhang 65 changes.

  The workpiece may be of any type as long as it includes a tapered portion.

  The present invention is suitable for gripping and moving a workpiece including a tapered portion.

  DESCRIPTION OF SYMBOLS 10 ... Grip mechanism 11, 12 ... Bracket, 16 ... Robot, 20 ... Fixed arm, 22 ... First claw, 23 ... Third claw, 30 ... Movable arm, 31 ... Support shaft, 32 ... Actuator, 35 ... Rotating member , 37 ... second claw, 38 ... third claw, 43 ... concave portion provided on the claw, 44 ... convex portion provided on the claw, 50 ... swing mechanism, 60, 60B, 60C ... work, 70, 70B ... work movement Mechanism: 71 ... Main frame, 72 ... First subframe, 73 ... Second subframe, 74 ... Connecting member, 75 ... Clipping mechanism, 76 ... Slider, 77 ... Subframe moving mechanism, 83 ... Fifth claw, 84 ... 6th nail, 90 ... rotary mechanism.

Claims (6)

A gripping mechanism that is attached to the tip of a robot and grips a workpiece,
A bracket connected to the tip of the robot;
A fixed arm extending from the bracket;
A first claw and a third claw provided at a tip of the fixed arm and arranged at a predetermined interval in a direction perpendicular to the extending direction of the fixed arm;
A movable arm supported swingably on the bracket via a support shaft extending in a direction perpendicular to the extending direction of the fixed arm, and an actuator provided on the bracket for swinging the movable arm;
A rotating member attached to the tip of the movable arm so as to be rotatable up to a predetermined angle around the axis of the movable arm, and rotated by the pressing force of the workpiece;
A gripping mechanism comprising a second claw provided corresponding to the first claw and a fourth claw provided corresponding to the third claw on the rotating member.   The gripping mechanism according to claim 1, wherein the actuator is an air cylinder unit.   The gripping mechanism according to claim 1, wherein unevenness for preventing slipping is formed at the tips of the first to fourth claws. A workpiece moving device that includes the gripping mechanism according to any one of claims 1 to 3 and moves the workpiece,
The robot;
A main frame attached to the tip of this robot;
A first subframe extending perpendicularly from one end of the main frame and supporting the gripping mechanism;
A second subframe extending perpendicularly from the other end of the main frame;
A workpiece moving device comprising: a pinching mechanism provided at a tip of the second subframe and having a fifth claw and a sixth claw for pinching the workpiece. The second subframe is movably attached to the main frame,
The workpiece moving mechanism according to claim 4, further comprising a subframe moving mechanism that moves the second subframe toward or away from the first subframe on the main frame.   6. The workpiece moving mechanism according to claim 5, wherein a rotary mechanism is interposed in the second subframe or a connecting member that connects the pinching mechanism to the second subframe, so that the pinching mechanism can be turned. .

Images