JPS583633Y2 - tool clamp device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tool clamping device, and more particularly to a tool clamping device for clamping a tool attached to a spindle rotatably supported by a main body and a spindle.

Conventionally, as shown in FIG. 1, this type of tool clamping device has a main body 1 rotatably supporting a spindle 2 via a pair of bearings 3, and the spindle 2 has a tapered mounting hole 4 and a large diameter The part 5, the mounting hole 6, and the vertical hole 7 are bored in communication with each other, and a clamper 9 that is hollow and equipped with a ball 8 is slidably inserted into the mounting hole 6, and is screwed and fixed to the clamper 9. The rod body 10 is urged upward by the clamp spring 11 to position the ball 8 in the mounting hole 6.

On the other hand, the tool 12 includes a tapered tool holder 13 that fits tightly into the tapered mounting hole 4, and a pull stud 1 having an enlarged portion 14 that is clamped to the clamper 9 by a ball 8.
5 are integrally formed.

Then, to clamp the tool 12 to the spindle 2,
Rod body 10 with piston rod IT of unclamp cylinder 16
is pushed downward against the clamp spring 11 to position the ball 8 in the large diameter portion 5, and the pull stud 15 and tool holder 13 are inserted into the mounting hole 4 of the spindle 2.

At this time, since the ball 8 is located in the large diameter part 5, the bulge part 1
4 passes over the ball 8 and faces into the clamper 9.

After that, when the piston rod 17 of the unclamping cylinder 16 is retracted, the clamper 9 is pulled upward via the rod body 10 and the clamp spring 11, the tool holder 13 is tightly fitted into the mounting hole 4, and the ball 8 is inserted into the mounting hole 6. Since the pull stud 15 is in this position, the bulging portion 14 of the pull stud 15 is regulated by the ball 8 and is prevented from being pulled out, and the tool 12 is clamped within the spindle 2.

In this manner, in the conventional tool clamping device, the tool 12 is clamped into the spindle 2 via the ball 8 and the pull stud 15 by the spring force of the clamp spring 11, and the unclamp cylinder 16 resists the spring force of the clamp spring 11. Since the structure is such that the clamper 9 is moved to release the clamp, it has the following disadvantages.

■ The unclamping force (unclamping force) requires a thrust force greater than that required to clamp the tool 12 in order to unclamp the clamp spring 11 by overcompressing it, and this force adversely affects the bearings 3 of the spindle 2. Durability decreases because of this.

■ Clamping is performed only by the spring force of the clamp spring 11, so the clamping force is proportional to the spring load.However, the length of the spindle 2 cannot be made too long due to constraints on the processing of the main body 2, so the clamping force must be Spring 11
Since the length of the mounting space is also shortened, it is necessary to increase the rigidity of the clamp spring 11 in order to increase the clamping force.

However, if the rigidity of the clamp spring 11 is increased too much, the clamp release force by the unclamp cylinder 16 will become very large, which is not preferable.

For this reason, it is difficult to increase the clamping force of the tool 12.

The present invention was devised in view of the above circumstances, and its purpose is to provide a tool clamping device that can increase the clamping force of the tool.

An embodiment of the present invention will be described below with reference to FIG.

Note that members that are the same as those in the prior art have the same reference numerals. A hollow hole 20 is bored in the tool holder 13, and a sleeve 21 is inserted into the hollow hole 20.

An opening 22 is bored in the peripheral wall 13a of the tool holder 13, and a lock ball 23 faces inside the opening 22.

On the other hand, the tapered mounting hole 4 of the spindle 2 is provided with a recess 24 into which the lock ball 23 is fitted.

Further, the base end of the pull stud 15 is fitted into the tool holder 13 and the sleeve 21, and is pulled downward in the figure by an unclamping spring 25, and a conical wedge 26 is integrally formed in the center thereof. The conical wedge 26 faces the lock ball 23 and is configured to push the lock ball 23 radially outward when moved upward in the figure.

Next, the operation will be explained.

First, in order to clamp the tool 12 to the spindle 2, the piston rod 17 of the unclamp cylinder 16 pushes the rod body 10 downward against the clamp spring 11 to position the ball 8 in the large diameter portion 5. Insert the pull stud 15 and tool holder 13 into the mounting hole 4 of the spindle 2.

At this time, since the ball 8 is located in the large diameter part 5, the bulge part 1
4 passes over the ball 8 and faces into the clamper 9.

At this time, the pull stud 15 is pulled downward by the unclamp spring 25, so the wedge 26 is attached to the lock ball 23.
Since the tool holder 13 can be detached and moved into the tool holder 13, the tool holder 13 can be easily inserted into the mounting hole 4.

After this, when the piston rod 17 of the cylinder 16 is retracted, the clamper 9 is pulled upward via the rod body 10 and the clamp spring 11, and the ball 8 is located in the mounting hole 64, so that the bulging portion 14 of the pull stud 15 8 and is pulled upward through the bulge 14 so that the tool holder 13 and the mounting hole 4 of the spindle 2 are tightly fitted, and the pull stud 15 resists the unclamping spring 25. The lock ball 23 is moved upward and pushed outward by the wedge 26 to fit into the recess 24 of the mounting hole 4 of the spindle 2.

This locks the tool holder 13 from being removed.

As described above, the tool 12 is clamped within the spindle 2 by the lock ball 23 and the recess 24, and the clamping force can be increased without increasing the spring load of the clamp spring 11.

To remove the tool 12, move the clamper 9 downward against the clamp spring 11 using the clamp cylinder 16 through the rod 10 so that the ball 8 faces the large diameter portion 5, and the pull stud 15 will be unclamped. Since the bulge 14 is pulled downward by the spring 25, it passes over the ball 8 and separates from the clamper 9, and the wedge 26 separates from the lock ball 23, allowing the lock ball 23 to separate from the recess 24. can be removed from the mounting hole 4 of the spindle 2.

Since the present invention is constructed as described above, the tool 12 can be clamped to the spindle 2, and the clamping force can be increased.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional example, and FIG. 2 is a sectional view showing an embodiment of the present invention. 2... Spindle, 4... Tapered mounting hole, 12... Tool, 13... Tool holder, 23... Mouth ball, 24... Concavity.

Claims (1)

[Scope of utility model registration request] The spindle 2 has a tapered mounting hole 4, a large diameter hole 5, and a mounting hole 6 formed in succession, and a cylindrical clamper 9 equipped with a ball 8 that can freely move in and out of the mounting hole 6 in the radial direction. is provided so that the ball 8 can freely slide between an unclamping position facing the large diameter hole 5 and a clamping position facing the mounting hole 6, and means for sliding the clamper 9 between the unclamping position and the clamping position. The tool 12 is provided with the tapered mounting hole 4. The tool holder 13 is provided with a pull stud 15 that is slid in the same direction as the clamper 9 to clamp and unclamp the spindle 2 by the clamper 9 and the ball 8. The tool holder 13 is provided with a lock ball 23 that is movable in the radial direction and that fits into a recess 24 formed in the tapered mounting hole 4, and the pull stud 15 is provided with a lock ball 23 that faces the lock ball 23. A wedge 26 is integrally formed, and the pull stud 15 is connected to the unclamp spring 2.
5, the wedge 26 moves and maintains a position away from the lock ball 23, and when the clamper 9 moves to the clamp position, the wedge 26 moves the lock ball 23 into the recess 2.
4. A tool clamping device characterized in that the tool clamp device is adapted to fit into the tool clamp device.