JPH026965Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pressure holding device that presses and holds a workpiece during cutting, etc., and is particularly suitable for pressing and holding the inner circumferential tapered surface or inner circumferential stepped part of the workpiece. Relating to a holding device.

Conventionally, an outward-opening chuck has generally been used to hold and fix the surface A of a workpiece such as the one shown at 30 in FIG. 4 during cutting or the like. This outward-opening chuck is provided with a variable diameter cylindrical member 31 provided with several slots fixed in the axial direction, and a shaft member 32 movable in the axial direction is provided in this cylindrical member 31. Shaft member 32 and cylindrical member 3
1 into tapered engagement, the diameter of the cylindrical member 31 is expanded by moving the shaft member 32 in the axial direction, and thereby the outer periphery of the cylindrical member 31 is brought into pressure contact with the inner peripheral surface 33 of the workpiece. It is meant to be held and fixed. In the drawings, 34 is a receiving member for abutment, and 35 is a jig plate.

This type of workpiece holding and fixing is relatively useful when it is difficult to grip or press the outer part of the workpiece, but Simply press and hold the
There was a problem in that it was difficult to obtain a strong holding force, and in particular, it was weak against force in the direction of separating the workpiece from the receiving member.

The present invention has been devised in view of these points, and will be described in detail below based on embodiments shown in the drawings.

Figures 1 and 2 show an embodiment of the present invention.
FIG. 1 shows the workpiece in a pressed and held state, and FIG. 2 shows the open state. In the drawings, reference numeral 1 denotes a fixed shaft fixed to a fixed member 9 with a nut 10, and a tip member 1 fixed to the tip thereof.
A tapered surface 2 is formed on the outer periphery of the tapered surface 1 . This tapered surface 2 may be formed directly on the fixed shaft 1, but by forming the tip member 11 which is detachably provided with a screw 12 in this way,
It has the advantage of being easy to replace when the tapered surface wears out. Reference numeral 6 denotes a variable diameter member, which has an inner peripheral tapered surface 4 that engages with the tapered surface 2 on the inner surface of the cylindrical body 3 provided with several slots, and a pressing flange 5 at the tip thereof. The fixed shaft 1
A drive shaft 1 having a hollow hole slidably inserted into the
It is fixed to 3. The drive shaft 13 has a piston 14 on its outer periphery, and the piston 14 is housed in a cylinder 15 formed in the fixed member 9. Reference numeral 16 denotes a guide plate for preventing rotation of the drive shaft, and this may be omitted depending on usage conditions. Further, the workpiece 3 is attached to the flange portion 5.
A tapered surface 17 corresponding to the tapered surface 36 of 0 is formed, and this tapered surface 17 presses the tapered surface 36 of the workpiece. This flange part 5
A fixed receiving member 8 having a receiving surface 7 is provided opposite to the receiving surface 7 . In addition, in the drawing, 19 is the fixed substrate 1
8, and this fixed member 1
The hole 21 of the workpiece 30 is inserted into the cylindrical protrusion 20 of 9.
By fitting the two, the workpiece 30 is positioned at a predetermined position. A tapered surface 22 is formed on the inside of the fixing member 19 and engages with a tapered surface 23 formed on the outer circumference of the variable diameter member 6 to perform a tapered engagement to reduce the diameter of the variable diameter member 6. This taper engagement may be omitted if the variable diameter member 6 itself has sufficient diameter reduction return force, but by providing it, a more reliable diameter reduction operation is ensured.

Next, to explain the operation, the state shown in FIG. 2 shows an open state in which the variable diameter member 6 has moved to the right in the figure. At this time, the outer diameter of the flange portion 5 is reduced, and in this state, the hole 2 of the workpiece 30
1 is inserted into the cylindrical protrusion 20 of the fixed member, and when pressure fluid is allowed to flow into the cylinder chamber 15 from one of the inlet ports 24, the piston 14 is moved to the left in the figure, and as a result, the variable diameter member 6 is also moved to the left in the figure. Due to this movement, the inner circumferential tapered surface 4 of the variable diameter member engages with the outer circumferential tapered surface 2 of the fixed shaft, and as a result, the flange portion 5 moves to the left in the figure while expanding its diameter, as shown in FIG. The tapered surface 1 as shown in
7 comes into pressure contact with the tapered surface 36 of the workpiece, thereby firmly holding the workpiece 30 between the tapered surface 17 and the receiving surface 7 of the fixed receiving member. At this time, the fixed shaft that is slidably inserted into the hollow hole of the drive shaft is positioned in the radial direction with respect to the hollow hole of the drive shaft. Since there is no axial misalignment with the variable diameter member, the diameter of the flange portion 5 is uniformly expanded. Next, when pressure fluid is allowed to flow into the cylinder chamber 15 from the other inlet 25, the piston 14 moves to the right in the figure, and the second
The state returns to the state shown in the figure. At this time, the outer diameter of the flange portion 5 is reduced by the engagement of the tapered surfaces 22 and 23 to a smaller outer diameter than the hole 21 of the workpiece, making it possible to remove and attach the workpiece.

According to the present invention, the flange portion 5 uniformly expands in diameter and moves in the axial direction to press and hold the workpiece, so that the inner circumferential tapered surface of the workpiece can be reliably pressed and held.

Further, FIG. 3 shows an example in which the inner peripheral stepped portion of the workpiece is pressed and held, and in this case, the end surface 27 of the flange portion 26 of the variable diameter member 6 is pressed against the stepped portion 38 of the workpiece 37.
The workpiece 37 is evenly pressed against the flange portion 2.
6 and the receiving surface 7 of the fixed receiving member. When opening, the variable diameter member 6 is moved to the right in the figure to separate the flange portion 26 from the stepped portion 38 and reduce its outer diameter, making it possible to pull out the workpiece. Note that other symbols in the drawings are the same as those in the embodiment described above, so explanations thereof will be omitted.

As mentioned above, in this invention, the diameter of the variable diameter member is expanded evenly while moving in the axial direction, so that the inner tapered surface and inner stepped part of the workpiece can be pressed and held evenly and reliably. It has the effect of being able to do the following.

[Brief explanation of drawings]

1 and 2 are cross-sectional views of an embodiment of the present invention, with FIG. 1 showing the pressed and held state, and FIG. 2 showing the open state. Further, FIG. 3 is a sectional view of another embodiment, and FIG. 4 is a sectional view of a conventional example. Explanation of symbols, 1... Fixed shaft, 2... Tapered surface, 3... Cylindrical body, 4... Inner peripheral tapered surface, 5... Flange part, 6... Variable diameter member, 7... Receiving surface, 8... Fixed receiving member , 13... Sleeve shaft, 14... Piston, 1
5...Cylinder chamber, 19...Fixing member.

Claims (1)

[Scope of utility model registration request] A tapered surface 2 is formed on the outer periphery of the tip of the fixed shaft 1 fixed in the axial direction, and an inner peripheral tapered surface 4 that engages with the tapered surface 2 is formed on the inner periphery of the cylindrical body 3 provided with a slot. A variable diameter member 6 having a pressing flange 5 formed at its tip is provided at one end of the drive shaft 13, and the fixed shaft 1 is slidably inserted into a hollow hole provided in the drive shaft. , the variable diameter member 6 is provided so as to be movable in the axial direction, and a fixed receiving member 8 having a receiving surface 7 is further provided opposite to the pressing flange portion 5. holding device.