JPS6348327Y2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> This invention relates to an improvement of a self-rotating finger chuck.

<Prior Art> A conventional finger chuck includes a plunger inserted into a stationary sleeve in which a cam groove is formed;
It consists of a finger provided at the tip of this plunger. By providing a protruding pin on this plunger that engages with the cam groove, the plunger moves forward and backward to rotate the plunger along the cam lead of the cam groove, thereby placing the finger in an unclamped state. In addition to
The finger is rotated at an angle according to the cam lead so that it escapes from the end face of the workpiece.

By the way, in automatic processing machines equipped with this type of rotating finger chuck, the workpiece is automatically fed toward the processing surface, and at the end of processing, the ejector pin is removed after unclamping the chuck. The structure is such that the workpiece is automatically ejected by the following methods.

However, in this type of processing device equipped with the conventional chuck, when the workpiece is unclamped, the plunger protrudes far beyond the periphery of the workpiece, so that when the workpiece is automatically inserted, the stroke of the feeder must be lengthened to reliably push the workpiece into the processing position. Also, when the workpiece is discharged by the ejector pin, the plunger and finger prevent the workpiece from falling, and the workpiece is caught or hit during the fall, so that the range of the falling position when the workpiece is discharged is not fixed. This causes the area of the discharge chute and the receiving surface of the receiving container to be large, and also causes problems such as the workpiece getting into unexpected places.

[Purpose of the invention] This invention minimizes the stroke of the automatic feeding device by minimizing the amount of protrusion of the fingers when clamping and unclamping the workpiece, and also reduces the falling position of the workpiece during ejection. The purpose is to be able to determine it with high accuracy.

<<Structure of the invention>> In order to achieve the above object, the present invention includes a plunger for driving a finger, a sleeve that is inserted into a fixed block and into which the plunger is inserted, and a mechanism that urges the sleeve forward. an elastic member formed in the fixed block for regulating the forward position of the sleeve; a cam groove formed in the sleeve; An object of the present invention is to provide a self-rotating finger chuck comprising a pin which rotates the sleeve at an angle along a cam lead of a cam groove when the sleeve advances, and a finger connected to the tip of the sleeve.

<<Example>> FIGS. 1 and 2 show a case where this invention is applied to a spindle device equipped with a diaphragm chuck.

In the figure, this diaphragm chuck is located at the tip of the spindle device 1, and includes a mounting plate 2 and a case 3 attached to the shaft end of the spindle (not shown), and a diaphragm 4 whose peripheral edge is fixed to the tip of the case 3.
Three chuck parts 5 are arranged at 120° intervals on the end face of the diaphragm 4, clamp blocks 6 are arranged on the inner circumference of the chuck parts 5, and 3 chuck parts 5 are mounted at 120° intervals through the diaphragm 4. The workpiece W is held at its outer circumference by the inner circumference of the clamp block 6 via chuck pawls 8, and the finger chuck 7 holds the flange end face. It is held and fixed to a seating surface provided on the inner circumferential end surface of the clamp block 6.

The finger chuck 7 is shown in Figures 1 and 3.
As shown in the exploded view, there is a drive plate 9 fixed to a clamp/unclamp rod (not shown) that is coaxial with the main shaft, and a fixing ring 10 and a mounting ring 11 are attached to the peripheral edge of the drive plate 9. Plunger 1 whose rear end is fixed through
2, a movable sleeve 13 inserted through the tip of the plunger 12, a fixed sleeve 14 inserted through the movable sleeve 13, and a finger 16 integrally fixed to the tip of the movable sleeve 13 via a fixing bolt 15. ing.

A stepped portion 18 is formed in the inner cylindrical portion of the movable sleeve 13, and correspondingly, a large diameter portion 19 is formed at the tip of the plunger 12, which abuts against the stepped portion 18 when the plunger 12 is in the retracted position. So sleeve 13
and plunger 12 are connected to each other, and the vehicle is configured to be able to move backward in this state.

Further, a large-diameter portion 20 is formed on the outer periphery of the rear end of the movable sleeve 13. Correspondingly, a stepped portion 21 is formed on the rear end of the inner cylindrical portion of the fixed sleeve 14. By engaging with the stepped portion 21, the forward position of the movable sleeve 13 is regulated.

Furthermore, a cam groove 22 is cut in a spiral shape on the outer periphery of the movable sleeve 13, and a pin 23 that slides along the cam groove 22 is fixed to the outer periphery of the large diameter portion 19 of the plunger 12. has been done.

A spring S for biasing the movable sleeve 13 toward the forward position and a spring receiving ring 25 for screwing the rear end of the spring S into a screw hole 24 formed in the fixed sleeve 14 are provided on the rear outer periphery of the movable sleeve 13. The step portion 2 provided on the fixed sleeve 14
By abutting the large diameter portion 20 on the movable sleeve 1, the forward position of the movable sleeve 13 is restricted.

In the figure, reference numeral 30 indicates a plurality of disc springs for equalizing the difference in clamping force caused by the flat vibration of the drive plate 9, and 31 indicates a nut for stopping the rear end of the disc spring 30.

Next, the operation of the finger chuck 7 constructed as above will be explained.

When the clamp/unclamp rod moves forward from the states shown in Figs. 1 and 2, the drive plate 9 moves forward, opening a gap between the large diameter part 19 and the stepped part 18 of the plunger 12. In this state, the spring S The movable sleeve 13 advances due to the biasing pressure, and the forward movement is stopped when the large diameter portion 20 at the rear end comes into contact with the stepped portion 21 of the fixed sleeve. At this stage, the end face of the workpiece W is unclamped.

On the other hand, the plunger 12 moves forward as it is, and as a result, the movable sleeve 13 rotates by an angle along the cam lead shape of the cam groove 22 (as shown in the direction of arrow A) while the forward position is restricted. As a result, the finger 16 at the tip advances to the minimum necessary unclamping position with respect to the workpiece W, and then
Rotate in the direction of arrow A to completely escape from the outer periphery of the workpiece W. Note that during clamping, the operation order is reverse to that described above, so a description thereof will be omitted.

《Effect of the idea》 Since this idea is structured as above,
When clamping/unclamping a workpiece, the fingers move the minimum distance necessary to clamp/unclamp the workpiece before turning, so the stroke during automatic insertion is short, and the interference distance with the processing equipment is also small. Become. Furthermore, when ejecting the workpiece, the finger or its shaft does not interfere with the workpiece, and the workpiece can be ejected to the ejection position with high accuracy.

In addition, since the moving distance of the fingers during clamping and unclamping is extremely small, this invention can be used not only for workpieces with flanges as shown in the embodiment, but also for chucks of workpieces with grooves cut on the outer periphery. Can be used.

In other words, if the tip of the finger is formed to a length that allows it to fit into the groove, and the necessary strokes for clamping and unclamping are set taking into account the width of the groove, it is possible to handle workpieces with such grooves. Even if the workpiece has no other part to check the thrust surface of the workpiece, it can be easily clamped and unclamped.

Further, because of this, it is possible to clamp even a workpiece that does not have a flange portion necessary for chuckling, so that end face machining of the workpiece can be performed with high accuracy. Therefore, it is extremely effective especially for workpieces that require high accuracy in end face machining.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the application of this invention to a diaphragm chuck, FIG. 2 is a side view with the same portion cut away, and FIG. 3 is an exploded perspective view of the finger chuck. 16...Finger, 12...Plunger, 1
3...Movable sleeve, 14...Fixed sleeve (fixed block), 20...Large diameter portion, 21...Stepped portion,
22...Cam groove, 23...Pin, S...Spring (elastic member).

Claims (1)

[Scope of utility model registration request] a plunger for driving the finger; a sleeve that is inserted into a fixed block and into which the plunger is inserted; an elastic member that biases the sleeve toward the forward movement side; a cam groove formed in the sleeve; a pin protruding from a plunger to engage with the cam groove and rotate the sleeve by an angle along a cam lead of the cam groove as the plunger moves forward; Rotating finger chuck with fingers connected to the tip of the sleeve.