JPS6018244Y2 - diaphragm chuck - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a diaphragm chuck suitable for machine tools, particularly grinders.

Various diaphragms and chucks have been devised in the past depending on the workpiece, but since the workpiece is gripped and rotated by the chuck jaws of the chuck mounted on the rotating spindle, the center of rotation of the workpiece is the chuck's center of rotation. The accuracy of the chuck jaws greatly affects machining accuracy, as it is determined by the shape of the jaws and the shape of the workpiece.

Also, depending on the workpiece, there are many cases where the processing certificate and the location where the rotational force is transmitted to the workpiece are different.

For example, in a cylindrical grinding machine, it is common for both centers to transmit the rotational force to the workpiece at other locations.For example, Utility Model Publication No. 46-5433 uses a floating chuck jaw, The hydraulic (pneumatic) mechanism used to open the cylinder rotates with the workpiece, which requires a rotary joint for hydraulic oil, resulting in high costs. The workpiece is held with a gap by a bolt, but the workpiece is inserted into the open jaw, the piston is moved to the left to clamp it, and then the piston is moved to the left to push the diaphragm.Although the edge of the bottle is cut, the reaction force of the chuck gripping force is bolt 1
Since the frictional force is applied to the end face of 2 and has a negative effect on the floating of the claw, there is room for improvement in terms of high precision machining and durability.

This invention improves on these points by providing a hydraulic mechanism for opening the chuck jaws on the stationary side, separating it from the floating diaphragm and the rotating part of the chuck jaws, and bending the diaphragm from the stationary side to open the jaws. As if opening,
Further, the present invention provides a diaphragm chuck in which a member for opening the claws of the diaphragm is provided so as not to come into contact with the diaphragm after gripping the workpiece, so that only rotational force is transmitted to the workpiece by the diaphragm.

Embodiments of this invention will be described below based on the drawings.

A spindle 2 that is slidable in the axial direction and capable of longitudinal positioning is supported by the spindle sleeve of the headstock 1, and a center 3 is supported at the tip of the spindle.
is fitted.

A diaphragm support 7 is fastened to an intermediate plate 6 that is fastened to the side surface of a pulley 5 which is supported by a bearing 4 on the main shaft sleeve, and a diaphragm position regulating disk 8 is fitted onto the side surface of the intermediate plate 6. A plurality of flanged spring guide pins 9, eight in this example, are provided on the diaphragm support 7 in the axial direction, penetrating the disc and being spaced at equal intervals around the circumference of the side surface.

This flanged guide pin transmits rotational force to the diaphragm.

In addition, this flanged spring guide pin 9 has a diaphragm 1 in which a hole larger than the pin shaft diameter is bored corresponding to the guide pin position.
0 is held and the workpiece is not gripped by the spring 11 interposed between the diaphragm and the collar of the spring guide pin 9, the diaphragm is lightly pressed against the side edge of the regulating disc 8.

On the front surface of the diaphragm, eight chuck claws 13 having claw portions 12 for gripping the flanges of the workpiece W are arranged radially in eight pieces and are fixed to the diaphragm 10 with set screws 14 and back plates 15 and 16.

The back plate 15 has a holding portion with a narrow width and a mountain-shaped tip so as to easily distort the diaphragm.

A cylinder 17 surrounding the outer periphery of the diaphragm 10 to open the chuck claw is fixed to the main shaft 1, and a hollow piston 18 containing the diaphragm 10 is fitted therein.

A presser cylinder 19 having an engaging portion 19a for pressing the outer edge of the diaphragm 10 and a lever pressing portion 19b is tightly fitted into the hollow portion of the piston.

Further, eight levers 21 are pivotally supported on the diaphragm support 7 by a lever shaft 20 and are arranged radially between the chuck claws 13.

The inner end 21a of this lever 21 can be engaged with two pieces of the back plate 16, and the outer end 21b can be engaged with the pressing part 19b of the presser cylinder 19, so that when the chuck claw grips the workpiece W, The engaging portions at both ends are held in a neutral state in which they are idle by a spring 22 and a detent pin 23.

Then, the outer end 21b of the lever 21 and the pressing part 1 of the presser tube 19
9b is formed narrower than the gap between the diaphragm 10 and the retaining portion 19a of the presser cylinder 19, and when the piston is actuated, the lever 21 is first turned and the inner edge of the diaphragm is pushed.

In addition, dogs 25 and 26 are attached to a rod 24 that is attached to the piston 18 in the axial direction via a side plate so that the position can be adjusted.
7.28 is activated to detect opening and closing of the chuck.

29 is the tailstock shaft, 30 is the center of the tailstock shaft, 31 is a waterproof bellows provided at the end of the main shaft, 32 is a waterproof seal provided between the diaphragm 10 and the center 3, and 33 is the piston and chuck claw. Waterproof seal provided between ・34.3
5 is an oil supply/drainage path for the cylinder 17.

FIG. 1 shows a state in which the workpiece W is being gripped, the limit switch 27 outputs a signal to close the chuck, and the cylinder 1
7, pressure oil is sent to the oil passage 35 to the rear chamber, and the piston 1
8 is moving forward.

Therefore, the presser cylinder 19 is separated from the diaphragm 10 and the outer end 21b of the lever 21, and the inner end 21a of the lever 21 is also separated from the back plate 16 of the diaphragm 10.

That is, the diaphragm 10 is in its natural state, and the chuck claws 13 are performing a gripping action.

In this state, the pulley 5 is rotated and the workpiece W is longitudinally positioned by operating the main shaft while monitoring the fluctuation of the groove position of the workpiece.

Then, the grinding wheel is moved forward to perform the grinding process.

When the machining is completed, an unloading device (not shown) grips the workpiece, and in response to this gripping signal, the pressure oil to the cylinder 17 is switched, the pressure oil is sent to the oil passage 34 to the front chamber, and the piston 18 retreats.

Then, the pressing portion 19b of the presser cylinder 19, which is tightly fitted into the hollow portion of the piston, presses the outer end 21b of each lever 21 against the force of the spring 22.

When each lever 21 is rotated and its inner end 21a is pressed against two back plates 16), the diaphragm 10 is uniformly pushed toward the workpiece W, the chuck jaws 13 are slightly opened, and the gripping force is loosened. As it is), it is pushed and the gap between it and the regulating disk 8 becomes larger.

The engaging portion 19a of the rear presser cylinder 19, on which the inner end 21a of the lever 21 acts, contacts the outer edge of the diaphragm and pushes the diaphragm in the direction in which the chuck jaws open, distorting the diaphragm and completely closing the chuck jaws 1.
After opening 3, the diaphragm 10 is pressed against the regulating disc 8.

After the jaws 12 of the eight chuck jaws 13 are uniformly opened, the workpiece W is removed from the chuck 13 and a new workpiece is conveyed. Release the restraint and chuck jaw 13
grip the workpiece.

After this, the piston 18 moves forward and the inner end 2 of the lever 21
At the same time, gaps begin to form between 1a and the back plate 16, and between the diaphragm 10 and the holding portion 19a of the presser cylinder.

Then, the lever 21 is rotated by the spring 22 until the stop pin 23 comes into contact with the diaphragm support 7, and the gap is further enlarged, and the diaphragm 10 is placed in a floating state when the chuck claws 13 are gripping it.

Of course, this product can also be used as a put center headstock.

As detailed above, the cylinder piston device for opening the diaphragm is placed on the stationary side and separate from the rotating member of the diaphragm/chuck claw, so there is no need to use a rotating joint and piping etc. can be simplified.

In addition, the member that opens the diaphragm jaws does not come into contact with the diaphragm after gripping the workpiece, so it can be held in a highly accurate floating state.The diaphragm is bent when the chuck jaws open, so the workpiece can be held at the center. This has the practical effect of being easily supported, allowing high-precision machining, and improving maintenance and durability.

[Brief explanation of the drawing]

Figure 1 is a schematic longitudinal sectional view of each part of this device, and Figure 2 is a schematic longitudinal sectional view of each part of this device.
It is a partial sectional view of each position I, II, II[, and IV of a figure. 1... Headstock, 2... Main spindle, 3...
...Center, 5...Pulley, 7...
diaphragm support, 10... diaphragm,
13... Chuck jaw, 17... Cylinder, 18... Piston, 21... Lever.

Claims (1)

[Scope of utility model registration request] A main shaft fitted with a center that is slidably supported in the axial direction on the head stock, and a diamond that is held floating in both the radial and axial directions on a diaphragm support that is integrated with a pulley that is rotatably supported on the head stock. a plurality of chuck claws disposed on the same circumference on the front side of the diaphragm; and a plurality of chuck claws supported on the diaphragm support body so as to be rotatable in a radial plane on the back side of the diaphragm, the inner end of which is rotatably supported on the diaphragm support body. a plurality of levers having a length capable of pressing the inner edges of the levers; and means for holding the levers in a state in which the outer and inner ends of the levers are loose when the claws grip the workpiece;
a cylinder fixed to the headstock and provided so as to surround the outer periphery of the diaphragm; a first contact surface fitted into the cylinder, enclosing the diaphragm and pressing its outer edge in the direction in which the claws open; a piston member having a second abutting surface that presses the outer end of the lever before the first abutting surface presses the outer edge of the diaphragm, and when the pawl is opened by movement of the piston member, the second abutting surface The first contact surface is configured to contact the outer edge of the diaphragm after the contact surface contacts the outer end of the lever, the lever is rotated, and the inner side of the lever contacts the inner edge of the diaphragm and is pressed toward the workpiece. A diaphragm chuck characterized by: