JPS637292A - Gripper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a gripping device that is used by being attached to a robot or the like.

(Prior Art) As a conventional gripping device for gripping fragile members, there is a device shown in FIG. 6. This gripping device includes fixed fingers (2) fixed to the -end of a base (1), and attached to the -ends of a pair of guide shafts (3).
3) has a movable finger (4) that can freely move towards and away from the fixed finger (2), and a pair of guide pins (5) are attached to the tip of the movable finger (4). Via a compression coil spring (6) attached to each of the pins (5),
A second movable finger (7) can move forward and backward in the same direction as the movable finger (4).
To grasp the six members to which the movable fingers (4) are attached, as shown in FIG. 7, move the guide shaft (3) forward in the direction of the arrow (^) to separate the movable fingers (4) from the fixed fingers (2). At this time, the second movable finger (7) is moved to the most advanced position in the direction of the distal end of the fixed finger (2) due to the bias of the compression coil spring (6) attached around each guide pin (5). be. In this state, when the member (W) is inserted between the tip of the fixed finger (2) and the second movable finger (7) and the guide shaft (3) is retreated, the movable finger (4) As shown in Figure 7, a stopper pin (8) is attached to this movable finger (4).
moves backward until it comes into contact with the fixed finger (2) and stops. Before this stop, the second movable finger (7) holds the member (It) together with the fixed finger (2) and retreats in the direction of compressing the compression coil spring (6). 6)
The member (W) is gripped by the fixed finger (2) due to the elastic force. Note that the gripping force of the member can be changed by adjusting the stop position of the movable finger (4) with a stopper pin (8).

As mentioned above, the gripping force of this gripping device can be changed by adjusting the stopper pin (8)6. However, this adjustment can be done by loosening the fixing nut (9) and
) is a mechanical method that changes the protruding length of the pin that is screwed into the pin, so it is difficult to adjust the degree of vibration accurately and cannot be adjusted programmably. Further, this gripping device has a second movable finger (7) at the tip of the movable finger (4).
Since the one-member gripping part is large, a large gripping space is required. Furthermore, since there are guides in two places, there are problems such as low accuracy.

(Problems to be Solved by the Invention) As mentioned above, in the conventional gripping device, the gripping force can be adjusted mechanically and cannot be done accurately and programmably, and the gripping portion is large. This requires a large gripping space, and since there are two guides, there are problems such as low accuracy.

This invention was made to solve this problem, and it is possible to change the gripping force accurately and programmably, and it is possible to accurately and programmably change various members with different strengths, especially fragile members, with the required gripping force. The purpose is to configure a gripping device for gripping.

[Structure of the invention]

(Means for Solving the Problem) In a gripping device capable of changing the gripping force, a pair of movable bodies are supported on a guide shaft attached to a base body so as to be able to slide into and out of contact with each other, and the second movable body Attach a flexible finger to the
A drive device is connected to the other movable body via a drive mechanism, the pair of movable bodies are connected by an elastic member, and the movable fingers and fixed fingers fixed to the base body grip the member. In addition, a sensor for measuring the distance between the pair of movable bodies is provided, and the driving device is controlled by a signal sent from the sensor.

(Function) A movable finger is attached to one of a pair of movable bodies that are slidably supported on a guide shaft and can be moved toward and away from each other, and a movable finger is attached to the other.
By connecting the devices and connecting the pair of movable bodies with an elastic body, the member can be gripped by the elastic force generated when the distance between the pair of movable bodies changes, and the distance between the pair of movable bodies can be changed. Since the grip force is determined by the sensor and the drive device is controlled based on the signal sent from the sensor, the gripping force can be adjusted with high precision and programmably.

(Example) The present invention will be described below based on an example with reference to one drawing.

Figures i1 to 3 show the configuration of a gripping device for gripping a plate-like member, which is an embodiment of the present invention. This gripping device is
It has a base (13) consisting of a bottom plate (10), a pair of end plates (lla) and (llb) erected on both ends of the bottom plate (10), and a cover (12).
) The mechanical part is provided inside. That is, a pair of guide shafts (14), (14) are attached in parallel to the pair of ends (lla) (llb) (llb), and ball bushes (15) are attached to these guide shafts (14), (14). A pair of movable bodies (16a)
, (16b) are supported so as to be able to slide and move toward and away from each other. Therefore, a movable finger (17
) is installed. The movable finger (17) extends forward through the negative end 4Jj (11a) of the base (I3), and has a claw (17) at its tip for gripping the member (11). 18a) is installed.

Further, the base end of this movable finger (17) is connected to the other movable body (1
6b) is inserted into the groove formed in 6b). - On the other hand, a rack (20) is attached to the other movable body (16b), and a pinion (21) that meshes with the rack (20) is the output of a motor (22) fixed to the bottom (10). attached to the shaft. The motor (22) may be a pulse motor or another motor such as a DC motor.

Thus, one movable body (16a) to which the movable finger (17) is attached, the rack (20) and the pinion (2
As shown in FIG. A pin (23) passing through the center of the other movable body (16b), and a compression coil spring (24) mounted around the pin (23) and located in a recess formed in the other movable body (16b). ) are connected by.

In addition, the pair of movable bodies (16a) and (16b) include
- The dog (25) attached to one movable body (16a) and the distance sensor (25) attached to the other movable body (16b)
26) is provided. The dog (25) is slidably supported by the - side movable body (16a), and has a dog pin (27) whose distal end is located in a recess formed in the movable body (16a), and around the distal end thereof. A compression coil spring (2
8), and a pair of movable bodies (16a) and (16
b) is in close contact with the distance sensor (26), and the output signal does not change unless the pair of movable bodies (16a) and (16b) are separated by a certain distance or more.

Furthermore, a pair of L-shaped fixed fingers (30) are attached to the outside of the - side end plate (lla) of the base (13) on both sides of the movable finger (17), and each tip thereof has a claw (18a) similar to the claw (18a) attached to the movable finger (17).
igb) is installed.

In addition, a pair of movable bodies (
A proximity sensor (31) or a limit switch is installed to regulate forward and backward movement of the gripping device 16a) and (16b), and a flange portion for attaching the gripping device to, for example, a robot is installed on the outside of the other end plate (llb). (32
) is provided.

Next, the operation of this gripping device will be described.

First, when the motor (22) is rotated and the other movable body (16b) is advanced via a drive mechanism consisting of a rack (20) and a pinion (21), as shown in FIG. 5(A), One movable body (16a) on the forward side of the movable body (16b) moves forward in close contact with the other movable body (16b) due to the bias of the compression coil spring (24), and the fixed finger (30
) and a claw (1) attached to the tip of the movable finger (17).
8a).

(18b) The interval widens. This nail (18a), (1
8b) The spacing should be large enough to allow insertion of the member (W) with sufficient margin. In this state, for example, the arm of the robot that supports this gripping device is driven so that the claws (18a
).

(18b) A plate member (W) is inserted between them.

Thereafter, when the motor (22) is reversely rotated to move the other movable body (16b) backward, the plate-like member (fishing claw (1)
8a) and (18b), the - side movable body (18a) retreats in close contact with the other movable body (18b), but this retreat of the - side movable body (18a) ,(
b) As shown in the figure, this plate-like member (υ) is connected to both claws (
18a).

(18b), and after that, only the other movable body (16b) retreats while compressing the compression coil spring (24), and the pair of movable bodies (16a) and (16b)
A gap is created in between. The distance sensor (26) remains in close contact with the movable dog (25) and does not change its output signal until the pair of movable bodies (16a) and (16b) are separated by a distance of -d. movable body (16a),
(16b) When the interval becomes d or more, the output signal changes due to separation.

Therefore, this output signal is sent to, for example, a control device and compared with a set value, and when the output signal reaches a certain value, the movable body (16b) is stopped. At this time, the plate member (W) is moved by the claw (1) by the elastic force of the compression coil spring (24) compressed by the retreat of the movable body (16b) alone.
8a) and (18b).

Note that the release of the gripped plate member (W) is the opposite of the above-mentioned gripping operation, and can be easily understood from the above explanation, so the explanation thereof will be omitted.

By the way, when the gripping device is configured as described above, the member is gripped by the elastic force of the compression coil spring (24) generated when the pair of movable bodies (16a) and (16b) are separated, and Movable body (16a), (15b)
Since the distance is controlled based on the output signal of the distance sensor (26), the gripping force can be adjusted programmably with high accuracy, and particularly fragile members can be gripped without being damaged or deformed. In addition, a pair of movable bodies (16a
), (16b) - constant interval d puzzle, compression coil spring (
24) When a certain gripping force is obtained by the elastic force,
Since the output signal of the distance sensor (26) is configured to change, the presence or absence of the gripping member can be automatically detected, and the member can be reliably gripped to prevent damage due to falling or the like.

Furthermore, this gripping device has a mechanical part housed in the base body (13), does not have a complicated structure in the gripping part, and is compact, so it can grip a member in a smaller gripping space than conventional gripping devices. can do. Furthermore, this gripping device has a structure in which the distance between the movable finger (17) and the guide shaft (14) that supports it via the movable body (16a) is small and no moment is generated. (17) The claw (18a) can be positioned accurately. In particular, the structure in which the proximal end of the movable finger (17) attached to the - side movable body (16a) is inserted into the groove formed in the other movable body (16b) makes the positioning accuracy more accurate. effective.

Although one embodiment of the present invention has been described above, the drive mechanism may be not only the rack and pinion shown in this embodiment but also other power transmission mechanisms such as a link mechanism and a belt. Also,
Other distance sensors may be used as long as they have the same measurement function.

Note that the gripping device of the present invention can also be applied to gripping members other than plate-shaped members.

〔Effect of the invention〕

A movable finger is attached to one of a pair of movable bodies that are supported by a guide shaft so as to be able to slide and be bonded to each other, a drive device is connected to the other, and the pair of movable bodies are connected by an elastic body. The structure is configured such that the member is gripped by the elastic force of the elastic body that occurs when the distance between the two movable bodies changes, and the gripping force is controlled based on the output signal of the sensor that measures the distance between the pair of movable bodies. Moreover, the gripping force can be adjusted programmably, and particularly fragile members can be gripped effectively. In addition, since the mechanism part is housed within the base and the gripping part is simple and small, it is possible to grip the member with a small gripping space. The spacing is small,
Since no moment is generated, the claws that grip the member can be positioned accurately.

[Brief explanation of drawings]

1 [iM to 5 are detailed explanatory diagrams of this invention,
Fig. 1 is a plan view showing the configuration of a gripping device that grips a plate-like member, Fig. 2 is a front view showing its cross section, Fig. 3 is an m-rum sectional view of Fig. 1, and Fig. 4 is an essential part. 5(A) and (Il) are respectively explanatory diagrams of the operation, FIG. 6 is a front view of the conventional gripping device, and FIG. 7 is an explanatory diagram of the operation. (13)...Base (14)...Guide shaft (16a), (16b) = Movable body (
17)--Movable fingers (18a), (18b)-claws
(20)--Rack (2])--Pinion
(22)...Motor (23)...Pin
(24)...Compression coil spring (25)...Dog
(26)... Distance sensor (30)...
Fixed finger (32)... Proximity sensor (W)...
・Plate member

Claims (1)

[Claims] a guide shaft supported by a base; a pair of movable bodies supported by the guide shaft so as to be able to slide into and out of contact with each other; a movable finger to which a claw for supporting a member is attached, a fixed finger fixed to one end of the base and having a claw for supporting the member in cooperation with the claw of the movable finger; a drive device connected to the other via a drive mechanism; an elastic body that connects the pair of movable bodies and provides the movable fingers with a gripping force to grip the member between the fixed fingers; and the pair of movable bodies. A gripping device comprising: a sensor that measures a body distance and sends a signal for controlling the driving of the driving device.