JPH03178793A - Gripper driving device of work handling robot - Google Patents

Abstract

PURPOSE:To miniaturize a holding member by composing it so as to move a dog used for detecting the holding state by the holding member of a work corresponding to the opening and closing motions of this holding member and to detect the holding state of the holding member with the detection of the moving position of this dog. CONSTITUTION:When a control valve means 12 is changed over to the nonworking position 12a thereof, a working fluid is fed to a cylinder device 8 which composes the opening and closing means of a holding member 62 via the position 12a this time. As a result, the piston of the cylinder device 8 is moved by the working fluid, driven in the direction that the holding member 62 is closed and a work W becomes being held by the holding member 62. On the other hand, at the detection means 83 side, the feeding of the working fluid to the cylinder device 8 is stopped and so the piston is again returned to the initial position thereof. Namely, a dog 82 is again returned within the detection range by a sensor 83. Consequently, the work being held can be detected by the holding member from the dog detection output to be obtained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a work handling robot that performs tasks such as automatically taking out a molded product from a mold. This invention relates to a drive control mechanism for a gripper device for gripping items.

(Prior Art) In a work handling robot that automatically takes out a molded product from the mold, a gripper device is supported on a horizontal axis mounted on a base. , is supported so as to be rotatable within a certain range around the axis of the horizontal axis, and is supported so as to be movable reciprocally over a certain range on this horizontal axis.The gripper device includes: A pair of gripping members are supported so as to be movable up and down, and the pair of gripping members can be opened and closed.The gripping operation of the molded product performed to take the molded product out of the mold is, for example, performed by a gripper device. It is moved horizontally so that it is located above the molded product, and then lowered to just above the molded product, and then the pair of gripping members are closed to grip a part of the molded product. .

Here, in such a gripping operation of a molded product, a means for detecting that the molded product is gripped by the gripping member is required. , a detection means such as a contact sensor is installed, the output from this sensor is taken out to the control circuit side via a lead wire, and based on this output it is detected whether or not the gripping member grips the molded product. Controls the opening/closing drive of the gripping member.

[Problem to be solved by the invention]

However, attaching the sensor directly to the gripping member in this way means that the size of the gripping member increases accordingly. If the gripping member becomes large, it may become difficult to take out the molded product depending on the type of molded product to be taken out. In addition, a lead wire for taking out the sensor output comes out from the gripping member, but connecting such a lead wire to the gripping member that has the largest movement range may hinder the movement of the gripping member. Yes, not desirable. Furthermore, the molded product or mold is in a high temperature state immediately after being molded, and it is not preferable to expose the lead wire to such high temperatures from the viewpoint of its durability.

In view of these conventional drawbacks, an object of the present invention is to provide a workpiece/workpiece having a structure that makes it possible to appropriately control the drive of a gripping member without directly attaching a sensor to the gripping member.
The object of the present invention is to realize a gripper drive device in a handling robot.

[Means to solve the problem]

The gripper drive device of the present invention includes a pair of gripping members for gripping a work such as a molded product, and the pair of gripping members are driven by an opening/closing drive means driven by a working fluid such as air. It is about to be done. The supply control of the working fluid to this opening/closing driving means is as follows:
This is done via a hydraulic circuit. Further, the open/close position of the gripping member is detected by a detection means.

Here, the opening/closing driving means is composed of a cylinder device driven by a working fluid, and a link mechanism that converts the reciprocating motion of the piston of the cylinder device into the opening/closing motion of the pair of gripping members, and The above detection means is composed of a cylinder device driven by a working fluid, a dog attached to a piston of this cylinder device, and a sensor for detecting the position of this dog.

On the other hand, the above-mentioned fluid circuit is provided with a control valve means, and this control valve means has a non-operating position where the working fluid is supplied toward the cylinder device of the sensing means and a cylinder of the opening/closing driving means where the working fluid is opened and closed. It can be switched to the operating position where it supplies towards the side of the device. Further, the fluid pressure circuit is kept in a cutoff state until the piston in the cylinder device of the opening/closing drive means moves a certain amount in the direction of closing the gripping member, and after it moves further, it is communicated with the cylinder device of the opening/closing drive device. It is equipped with a communication passage that is in a state of Further, the fluid pressure circuit includes a switching valve means, the switching valve means communicating with the first artificial boat to which working fluid is supplied from the control valve means in the non-actuated position, and the communication passage. A second inlet boat is provided, and an output port is provided which communicates with the cylinder device of the detection means.

Of the first and second input ports, a switching operation is performed so that the inlet port on the side to which the working fluid is supplied is communicated with the outlet port.

[Effect]

In this configuration of the gripper drive, when the control valve means is set in its inoperative position, working fluid is supplied to the first inlet port of the switching valve means through the control valve means. Therefore, since the first inlet port and the outlet port communicate with each other, the working fluid is supplied from the outlet port to the cylinder device of the detection means. As a result, the piston of the cylinder device is moved to one side by the supplied working fluid. ζHowever, if you set the dog so that it moves to one side in this way and is located outside the detection range of the sensor,
In such a state, dog detection output cannot be obtained from the sensor.

On the other hand, when the control valve means is switched from its non-operating position to its operating position, working fluid is then supplied to the cylinder device constituting the opening/closing drive means for the gripping member. As a result, the piston of this cylinder device is moved by the working fluid, the gripping member is driven in the closing direction, and the workpiece is gripped by the gripping member.

On the other hand, on the detection means side, the supply of working fluid to the cylinder device is stopped, so the piston returns to its initial position again. That is, the dog returns to the detection range of the sensor. From the dog detection output obtained as a result, it is detected that the workpiece is gripped by the gripping member.

Here, if the workpiece is not gripped by the gripping member, the gripping member is driven toward the completely closed position. However, when the piston moves beyond a certain amount, the communication passage opens and the working fluid flows through the communication passage to the second inlet port of the switching valve means. As a result, the second
The large roponite communicates with the outlet port, and the working fluid is again supplied to the cylinder device of the sensing means from the outlet port side.

This causes the piston to move from its initial position and the dog attached thereto to move out of the detection range of the sensor.

As a result, the dog detection output is no longer obtained from the sensor, and it is detected from the change in this output that the gripping member was unable to grip the workpiece.

〔Example〕

The present invention will be described in detail below with reference to the drawings.

First, FIGS. 2 and 3 show the overall configuration of the work handling robot of this example.

The work handling robot in this example is an air-driven type, and has a horizontal rotating shaft 3 supported on a base 2.
A support member 4 is mounted on the horizontal rotating wheel 3 so as to rotate integrally with the shaft and to be movable back and forth along the shaft. A main cylinder 5 is attached to this support member, and a gripper device 6 for gripping a workpiece is supported at the tip of a downwardly extending piston of the cylinder 5. The horizontal rotation shaft 3 is rotated by a rotation cylinder 7, the support member 4 supported by the horizontal rotation shaft is reciprocated thereon by the cylinder 4a, and the gripper device 6 is raised and lowered by the main cylinder 5. . By moving each of these members, the gripper device 6 is positioned three-dimensionally.

On the other hand, the gripper device 6 described above includes a cylinder device 61 supported at the tip of the piston of the main cinder 5, and a pair of gripping members 62, 62 supported at the tip of the piston of this cylinder device via a link mechanism. There is. Further, on the base 2, a cylinder device 8 is mounted vertically.
A dog 82 is attached to the tip of the piston 81 of this cylinder device, and a sensor 83 for detecting the dog is arranged on the side of the dog. These detect the gripping state of the gripping member 62. A detecting means for detecting is configured.

Next, referring also to FIG. 1, the drive system of the gripper device described above will be explained. In the cylinder device 61 of the gripper device 6, a screw head 64 is slidably disposed in a cylinder body 63 in an airtight state, and is always urged upward by a return spring 65. A pair of link members 66, 66 are pin-jointed to the lower end of the piston rod 64a extending downward from the piston head 64 in a state that opens downward to the left and right. It is pin-jointed to the upper end of member 62.62. The gripping members 62.62 are each supported pivotably around pins 67.67 at their intermediate positions, and gripping surfaces 62a, 62a are formed that are inclined downward from this support position to open left and right. ing. Here, the cylinder body 63 and piston head 6
The airtight chamber 6, which is defined by 4 and 4, has its upper end communicating with an air supply port 63a formed in the cylinder body 63. Further, an air passage 63b is formed inside the side wall of the cylinder body on which the piston head 64 slides, and the inner open end 63c of this air passage opens at the inner surface of the side wall of the cylinder body, and the other outer open end 63d opens at the outer periphery of the cylinder body. It is open on the surface.

Next, a control valve 12 is arranged between the air supply source 11, which is the working fluid, and the cylinder device 61 described above. This control valve 12 is an electromagnetic two-position switching valve,
When set to the non-operating position 12a, the air supply source 11 is communicated with the shuttle valve 13, and when set to the operating position 12b, the air supply source 11 is connected to the cylinder device 61. Connect to the side. The shuttle valve 13 is a switching valve with a first artificial port 13a, a second inlet port 13b and a single outlet port 13C, and communicates the inlet port on the side with higher supply pressure to the outlet boat side. . Among these artificial ports, the first inlet boat 13a communicates with the control valve 12 side, and the second artificial port 13b communicates with the outer open end 63d of the air communication path 63b of the gripper device. is connected to.

On the other hand, the outlet port 13c communicates with the cylinder device 8 for detecting the gripping state of the gripping member.

In the cylinder device 8, a piston head 81a is slidably mounted within the cylinder body 8a, and an airtight chamber 8b is defined by the piston head. This airtight chamber 8b is the outlet port 13 of the above-mentioned shuttle valve.
It is connected to C.

A dog 82 is attached to the tip of a cylinder rod 81 whose base end is fixed to the piston head 81a and which projects outward from the cylinder body. This dock 82 is biased by a return spring 84 to its lower end position. The stroke is set so that when the dog 82 protrudes most upwardly, it is out of the detection range of the sensor 83.

Next, the gripping operation of a workpiece in the gripper device will be explained with reference to FIGS. 1, 4, and 5. first,
As shown in FIG. 1, the gripping member 62 of the gripper device 6
．． 62 is positioned so that it can grip the object W to be taken out. At this time, the control valve 12 is set to its inoperative position 12a, so that air from the air supply 11 is directed to the first artificial bow 113 of the shuttle valve 13.
a, and is therefore supplied from there to the cylinder device 8 of the grip state detection means via the outlet port 13c.

As a result, the piston head 8b of the cylinder device 8 moves upward against the spring force of the spring 84, and the dog 82
is detected by sensor 83 [placed in the box]. On the other hand, on the gripper device 6 side, the piston head 64 is pushed by the spring force of the spring 65 and is at the upper end position.

Next, when the control valve 12 is energized and switched to the operating position 12b, the air supply source 11 is supplied into the airtight chamber 68 of the cylinder device 61 of the gripper device. As a result, the piston head 64 is moved downward against the spring force. This movement is transmitted to the pair of gripping members 62 via the pair of link members 67, and these gripping members pivot about their support pins 67 in a direction to close each other. As a result, a state in which the workpiece W is gripped is formed as shown in FIG. In this state, air is not supplied to the cylinder device 8 constituting the grip state detection means, so the cylinder head 81a of this cylinder device is pushed back to the lower position by the spring force of the return spring 84. Dog 82 is sensor 83
within the detection range. Therefore, from the output of the sensor 83,
It is detected that the workpiece W is gripped by the gripping member 62.

Here, the operation when the gripping members 62, 62 are not properly positioned and the workpiece W is not gripped by the gripping members will be described. In this case, as shown in FIG. 5, the gripping members 62 are closed until their gripping surfaces 62a are substantially in contact with each other. However, when the head 64 descends to the piston until it reaches this state, the head 64
has already passed through the inner open end 63c of the air passageway 63b, so the airtight chamber 68 has passed through the air passageway 63b.
It becomes connected to. As a result, the air supplied here flows out to the second inlet port 13b of the shuttle valve 13 via the communication path 63b. The air is then supplied to the airtight chamber 8b of the cylinder device 8 that constitutes the grip state detection means. As a result, the dog 82 is pushed up again and reaches outside the detection range of the sensor 83. Therefore, from this sensor output, it is detected that the workpiece W is not gripped by the gripping member.

Note that the example described above shows one embodiment of the present invention, and is not intended to limit the present invention to the structure of this example. For example, it goes without saying that the drive system may be a hydraulic drive system instead of the air drive described above.

〔Effect of the invention〕

As explained above, in the gripper drive device of the present invention, the dog used to detect the gripping state of the gripping member is moved in response to the opening/closing operation of the gripping member that grips the workpiece. By detecting the moving position of the gripping member, the gripping state of the gripping member is detected.

Therefore, according to the present invention, there is no need to directly attach a sensor to the gripping member as in the conventional case, and the gripping member can be made small in size. Further, there is no need to draw out the lead wire from the gripping member which has a large movement range.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing an example of the gripper drive device of the present invention, and Fig. 2 shows a workpiece in which the device of Fig. 1 is incorporated.
FIG. 3 is a side view of the robot shown in FIG. 2, FIG. 4 is an explanatory diagram showing the device shown in FIG. 1 in a state in which a workpiece is gripped, and FIG. FIG. 3 is an explanatory diagram showing a state in which the workpiece cannot be gripped. [Explanation of symbols] t--Work handling robot 6-Gelper device 6l-=-Cylinder device 62-Gripping member 63 b--One air passage 63c, 63d--Open end 66- Link member 8- Cylinder device 82 ... Dog 83 -- Sensor 11 -- Air supply source 12 -- Control valve 12 a -- Non-operating position 12 b -- Working position 13 -- Shuttle valve 13 a -- First inlet bow 13 b -- - Second inlet bow 13C-outlet port W---work. Toto Figure 2 Robet Figure 3 Figure 4 Figure 5

Claims (1)

[Scope of Claims] A pair of gripping members for gripping a workpiece, an opening/closing drive means driven by a working fluid to open and close the pair of gripping members, and a detection means for detecting an open/closed state of the gripping members. , a fluid pressure circuit that controls the supply of working fluid pressure to the opening/closing driving means, and the opening/closing driving means includes a cylinder device driven by the working fluid and a reciprocating motion of a piston of the cylinder device. It has a link mechanism that converts the pair of gripping members into opening and closing motion, and the detection means detects a cylinder device driven by a working fluid, a dog attached to a piston of the cylinder device, and a position of the dog. The fluid pressure circuit has a non-operating position in which the working fluid is supplied toward the cylinder device side of the detection means and an operational position in which the working fluid is supplied toward the cylinder device side of the opening/closing drive means. It is shut off until the piston in the cylinder device of the opening/closing drive means moves a certain amount in the direction of closing the gripping member, and after it moves further, the opening/closing drive means is shut off. A communication passage communicating with the cylinder device, a first inlet port to which working fluid is supplied from the control valve means in the non-operating position, and a second inlet port communicating with the communication passage;
switching valve means having an output port communicating with the cylinder device of the detection means, the switching valve means having a side of the first and second input ports to which the working fluid is supplied; A gripper drive device for a work handling robot, characterized in that an inlet port communicates with the outlet port.