JPH0116612B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a work gripper used in a loading device or the like.

[Prior art]

Generally, when a small-diameter workpiece is received from a magazine or the like and mounted on the end face of a large-diameter shaft, the gripper that grips it accurately positions and holds the supplied workpiece, and at the loading position, it The axis of the workpiece is precisely aligned with the shaft end surface on the same axis line, and then, while being held, the workpiece is pushed onto the large diameter shaft end surface using a pusher shaft or the like.

However, if the workpiece has abrasive grains on its outer periphery, such as a grinding wheel for an internal grinding machine, and is screwed into a quill provided at the tip of the grinding wheel spindle, the grinding wheel spindle is attached together with the quill. It is necessary to hold the grindstone in the gripper while rotating and push it into the quill while it is fixed, or alternatively to push the grindstone into the quill that is stationary while rotating in the gripper.

In this case, however, it is not possible to create a connecting portion larger than the diameter of the abrasive grains as a means for axially connecting the pusher shaft and the grinding wheel, and only a connecting means such as a hexagonal driver and a hexagonal hole can be used, for example.

Therefore, in the former pushing method, even if the pusher shaft presses the grindstone, the two do not necessarily connect immediately; instead, the tip of the shaft of the grindstone contacts the end surface of the quill, and rotates as it rotates. Only then can it be screwed into the quill while being axially connected and pressing the grindstone into a fixed state.

In addition, in the latter pushing method, it is necessary to hold the grindstone in a fixed state and connect the two to the rotating pusher shaft. It wears out over time and becomes unusable immediately, so it is recommended to use this type of workpiece to automatically feed it to an internal grinder, or to hold it while screwing it into other parts. This has not been done in the past.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned current situation, and it is an object of the present invention to provide a work gripper suitable for holding a work and supplying it to other parts by screwing it into the work.

[Structure of the invention]

In order to achieve the above object, the present invention prevents wear and tear on the gripper by holding a workpiece between a pair of rollers and rotating the rollers as the workpiece rotates. Examples will be described in detail with reference to the drawings.

〔Example〕

FIG. 1 is an exploded perspective view of a work gripper according to an embodiment of the present invention, and FIG. 2 shows the same in an assembled state.

In each figure, the work gripper 1 includes a swing body, that is, a positioning block 3 attached to the end face of a gear 2, a pair of grip plates 4 and 5 pivoted to both legs 3a and 3a of this positioning block 3, and each of these grip plates 4 and 5. Gripper blocks 7, 7 are mounted on the upper parts of gripper plates 4, 5 and have rollers 6, 6 rotatably mounted on their opposing surfaces, respectively, a stopper plate 8, and first and second tension springs 9, 10. ing.

The positioning block 3 is formed in a substantially crooked shape so as to be attached to the central cylindrical portion 2a of the gear 2 in a saddle-like manner, and has a long hole 3b with one end open at the lower end of the leg portion 3a extending below the leg portion 3a. 3b is formed, the positioning block 3 is crotched onto the cylindrical portion 2a, and then the screw 11 is inserted into the elongated hole 3b and screwed into the mounting holes 2b formed in the gear 2. Therefore, the positioning block 3 can be mounted for positioning, and conversely, when removing the positioning block 3, it can be easily pulled out by loosening the screw 11, which facilitates replacement work when changing tooling. I have to.

The gripper plates 4 and 5 are pivotally attached to the legs 3a and 3a via shafts 12 and 12, respectively, and are opposed to each other so as to be able to swing around the legs 3a and 3a.
There is a pin 1 on the swinging end side of both gripper plates 4 and 5.
The above-mentioned first tension spring 9 is suspended via 3 and 13, and urges both plates 4 and 5 inwardly toward each other.

One gripper plate 4 is used to determine the reference position of the workpiece W held therein, and is in contact with a stopper plate 8 fixed to the positioning block 3 to restrict its inward rotation. At the same time, a second tension spring 10 is suspended between the positioning block 3 and the gripper plate 4 via pins 14, 14, and urges the gripper plate 4 inwardly with a stronger force than the other gripper plate 5. I try to maintain my position.

Further, the other gripper plate 5 rotates inward to come into contact with the outer periphery of the workpiece W that has been set at the reference position, and is held by the biasing force of the first tension spring 9. Then, with the gripper 1 positioned at the workpiece W supply position, the gripper plate 5 hits an abutment block or the like (not shown), thereby opening it.
Work W is now being received.

Each of the rollers 6 is rotatably supported in a semi-cylindrical groove 7a formed in the gripper block 7 via a shaft 15 that is attached to each of the plates 4, 5, and the outer periphery of protrudes from the opposing surface of each block 7, and positions the workpiece W supplied here between the three points of each roller 6 and the upper surface 3c of the positioning block 3. Work W with biasing force
It is designed to hold.

It goes without saying that the mounting position of the roller 6 is set higher than the radius of the workpiece W.

Therefore, when the workpiece W held by the gripper 1 is rotated and pushed out from the gripper 1, each roller 6, 6 rotates in accordance with the rotation of the workpiece W, and as a result, the gripping portion of the gripper 1 does not move at all. The workpiece W can be supplied to the counterpart component side without being damaged.

Figure 3 shows the gripper 1 connected to the workpiece supply head 2.
0, the head 20 is capable of reciprocating between the work waiting position and the parts supply position via supply rods 21 and 22, and the gripper 1 is placed in the center of the head 20. A hydraulic motor 24 rotatably supports the mounted gear 2 and has a gear 23 that meshes with the gear 2; stoppers 25, 25 for positioning the vertical and horizontal positions of the gripper 1; Proximity switches 26, 26 are arranged, and furthermore, a pusher shaft 27 that coincides with the center position of the workpiece W at the 90° rotation position of the gripper 1 and has a coupling means such as a hexagonal driver etc. protrudes and retracts in a direction perpendicular to the plane of the paper. They are freely placed.

Therefore, gripper 1 changes from the state shown in the figure.
When turning 90 degrees, pusher shaft 2 receives this signal.
7 protrudes, and the workpiece W is pushed out from this against the biasing pressure of the first spring 9, and is supplied to the mating part. Note that even if the pusher shaft 27 does not rotate and the other component rotates, or vice versa, the W is supplied while rotating while rotating the rollers 6, 6 inside the gripper 1. Therefore, wear and tear on the gripper itself is prevented.

〔Effect of the invention〕

As described above in detail with reference to the embodiments, the workpiece gripper according to the present invention is designed to hold the workpiece between rotating rollers. Even in the case of a loading method in which parts are supplied, the gripper can be carried out without wear and tear, and its positioning accuracy can be maintained.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of a work gripper according to the present invention, FIG. 2 is a perspective view showing the assembled state, and FIG.
The figure is a front view showing a case where the work gripper of the present invention is applied to a work supply head. 1...Work gripper, 2...Gear (swing body), 3...Positioning block, 4, 5...Gripper plate, 6...Roller, 7...Gripper block, 9, 10...Tension spring.

Claims (1)

[Claims] 1. A positioning block that is removably positioned and fixed to the gear and can rotate integrally with the rotation of the gear, and a positioning block that is pivotally attached to the end face of this positioning block,
a pair of gripper plates facing each other so as to be able to swing from this point; a first tension spring that is suspended between both gripper plates and urges the swinging ends of both gripper plates inwardly; A stopper plate is suspended between the one gripper plate and the positioning block, and the stopper plate is suspended between the one gripper plate and the positioning block, and the stopper plate is suspended between the one gripper plate and the positioning block. a second tension spring biased with a force stronger than the spring; a gripper block attached to each gripper plate at the protruding end from the positioning block of each gripper plate; a roller having a portion protruding from the opposing surface of each of the blocks;
A workpiece gripper that positions a workpiece between points, holds the workpiece by the biasing force of the tension spring, and moves the workpiece to a predetermined position by rotation of the gear.