JPH0631566A - Clamping device - Google Patents

Abstract

PURPOSE:To provide a clamping device which can carry out the work onto the obverse and reverse surfaces of a work continuously, obviating the necessity of the complicated work such as replacement work. CONSTITUTION:As for a cylinder body 1, a collet 4 is arranged in demountable manner at the opened end of a cylinder 1d which has a variety of diameters and is drilled in penetration in the direction crossing at right angle with the main spindle 104 of a dividing board 104, and a piston 3 having a variety of diameter is accommodated inside, and a holding hook driving shaft 5 for opening/closing-driving a plurality of holding hooks 4b of the collet 4 is connected with the different diameter piston 3. A working hole 4c which penetrates through in the axial direction and the working hole 3d are drilled on the collet 4 and the piston 3 having a variety of diameter, and a work 400 can be worked from the front surface side of the collet 4 holding the work 400 and from the back surfaces side on the side of the piston 3 having a variety of diameters.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp device,
In particular, the present invention relates to a technique that is effective when applied to a work gripping work in an automatic processing machine or the like.

[0002]

2. Description of the Related Art For example, in the field of machining, a numerical control (NC) mechanism is provided and a plurality of machining tools are automatically switched to continuously perform a plurality of types of machining on the same work (workpiece). Machining centers and other automatic processing machines have become widespread.

Usually, in such an automatic processing machine, for example, the work is fixed on the XY table with a jig or a bolt so as not to impair the versatility of the automatic processing machine. Was common.

Regarding automatic machine tools such as machining centers, for example, "Mechanical Engineering Dictionary" published by Asakura Shoten Co., Ltd. on March 20, 1990, P961 to P962.
And the like.

[0005]

However, in the work fixing technique such as the above-mentioned conventional technique, a plurality of types of processing can be continuously performed on a specific side surface of the workpiece facing the processing tool. If it is necessary to process both front and back surfaces of the workpiece, XY is required for both front and back surfaces.
There has been a problem that setup change such as complicated attachment / detachment work of the work on the table is required, and the advantage of continuous machining by automatic tool exchange on the machining machine side cannot be fully utilized.

An object of the present invention is to provide a clamp device which can continuously perform processing on both front and back surfaces of a work without requiring complicated work such as setup change.

Another object of the present invention is to provide a clamp device which is simple in structure and maintenance and capable of continuously processing both front and back surfaces of a work.

Still another object of the present invention is to provide a clamping device capable of continuously processing both front and back surfaces of a work with a small occupied space.

[0009]

That is, the clamp device of the present invention is formed with a cylinder main body fixed to the main shaft of the indexing mechanism and a large diameter portion formed through the cylinder main body in a direction intersecting the main shaft. A different-diameter cylinder consisting of a small-diameter part, and detachably fixed to one end of this different-diameter cylinder,
A collet having a through hole in which a plurality of gripping claws for gripping a workpiece by expansion and contraction deformation are planted around the collet, and first and second fluids fitted to different diameter cylinders. It is inserted through the different diameter piston that separates the chamber and the collet through hole, the inner end is detachably connected to the different diameter piston, and the outer end is slidably contacted with multiple gripping claws to expand and contract. A gripping pawl drive shaft formed with a tapered portion for controlling the closed deformation, and at least one first working hole formed around the gripping pawl drive shaft so as to axially penetrate through a piston having a different diameter and a collet. Or a second work hole formed by penetrating the different diameter piston and the gripping pawl drive shaft in the axial direction, and the first work hole.
And a fluid passage that communicates with the second fluid chamber and that supplies and discharges the pressurized fluid.

Further, the clamp device of the present invention is claim 1.
In the clamp device described above, one end is fixed to the collet side and the other end is movable relative to the different diameter piston inside the first working hole that axially penetrates the different diameter piston and the collet. The cylindrical body is connected to the cylindrical body, and the cylindrical body also serves as a slip prevention means for preventing idling of the different diameter piston.

The clamp device according to the present invention is also defined in claim 1.
Alternatively, in the clamp device according to the second aspect, a packing groove is formed in the inner peripheral portion of the different diameter cylinder at a position separating the first and second fluid chambers, and the piston packing is accommodated in the packing groove. is there.

The clamp device according to the present invention is the clamp device according to claim 1, 2 or 3, wherein the first and second fluid passages are concentrated at the rear end portion of the main shaft through the cylinder body and the main shaft. The main shaft is connected to an external fluid pressure circuit at the outer end of the main shaft.

[0013]

According to the above-described clamping device of the present invention, the work held by the gripping claws of the collet is machined from the front side of the collet, and the different diameter piston and the collet are provided around the gripping claw drive shaft. At least one first working hole that is bored through in the axial direction, or a second hole that is bored through the different diameter piston and the gripping pawl drive shaft in the axial direction.
Machining from the back side through the work hole can be realized without requiring a complicated work for removing the work.

Further, since the cylindrical body is provided inside at least one first working hole which is formed by penetrating the different diameter piston and the collet in the axial direction, the cutting waste generated during the machining is different. Since it is surely discharged to the outside without staying in the radial cylinder, maintenance management becomes simple, and a special idling prevention mechanism is not required, and the structure can be simplified.

Further, by disposing the piston packing in the packing groove formed on the inner peripheral surface of the different diameter cylinder, the different diameter piston can be provided as compared with the case where the piston packing is provided on the outer peripheral portion of the different diameter piston. The axial dimension of can be shortened, and miniaturization is possible.

[0016]

Embodiment 1 Hereinafter, a clamp device which is an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic sectional view showing a main part of a clamp device according to an embodiment of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a side view thereof.

The cylinder body 1 is fixed to the main shaft 104 of the indexing board 100 via an integrally formed base 1c.

The main shaft 104 of the indexing disk 100 is rotatably supported by a plurality of bearings 105 and 106, and torque is generated by fluid pressure via a gear 107 and a gear 108 provided at the inner end. By being connected to the drive shaft 110 of the rotary actuator 109, the rotary actuator 109 is rotated in a desired direction at a desired angle.

Bearing 105 and bearing 106
A stopper 111 having a protruding portion 111a formed in the radial direction is fixed to the outer peripheral portion of the main shaft 104 between them by a screw (not shown), and two positioning screws 112 screwed to the side surface of the indexing board 100. And positioning screw 1
By rotating the main shafts 104 in the opposite directions to the position where the protrusions 111a come into contact with each of the shafts 13, the 180 degree indexing angle of the cylinder body 1 supported by the main shafts 104 is set. There is.

On the other hand, the cylinder body 1 has a different diameter hole penetrating therethrough in a direction orthogonal to the axial direction of the main shaft 104 supporting the cylinder body 1, and a packing 2a at one end of the different diameter hole. With the head cover 2 attached via the above, a different diameter cylinder 1d having a structure in which small diameter portions are located at both ends of the large diameter portion is formed in the axial direction.

Inside the different diameter cylinder 1d, a small diameter rod portion 3 is provided at both ends of a large diameter piston portion 3a in the axial center.
A piston 3 having a different diameter, in which b and 3c are integrally formed, is accommodated, and a fluid chamber A and a fluid chamber B are formed on both sides of the piston portion 3a.

Between the different-diameter piston 3 and the head cover 2, there is provided a slip prevention pin 2b for preventing idling around the shaft without restraining axial displacement of the different-diameter piston 3. .

The fluid chambers A and B are bored inside the cylinder body 1 and are connected to a plurality of independent fluid passages 1a and 1b, one end of which is open at the end face of the base 1c. Further, these fluid passages 1 a and 1 b are individually communicated with a plurality of fluid passages 101 a and 101 b which are formed by penetrating the main spindle 104 of the indexing disk 100 in the axial direction, respectively. A pressurized fluid such as compressed air or oil is supplied to or discharged from the fluid chambers A and B without restraining the rotational movement of the main shaft 104 via a pipe adapter (not shown) provided on the end side. Has become.

In the different diameter cylinder 1d of the cylinder body 1, a packing groove 1e for accommodating the piston packing 1f is formed on the inner circumference of the large diameter part of the different diameter piston 3 for accommodating the piston portion 3a. Further, a rod packing 1g and a rod packing 1h are attached to the inner circumference of the small diameter portion of the different diameter cylinder 1d through which the rod portions 3b and 3c of the different diameter piston 3 are inserted.

A collet 4 having a structure in which a plurality of gripping claws 4b are planted around a central through hole 4a is detachably fixed to the opening of the different diameter cylinder 1d on the rod portion 3b side by a fixing screw 4d. Has been done.

A tapered portion 5a is formed at the outer end of the through hole 4a in the center of the grip claw 4b, which is in sliding contact with the grip claw 4b.
The grip end drive shaft 5 connected to the rod portion 3b of the different diameter piston 3 through the screw 5b is inserted through the inner end portion. Then, the grip claw drive shaft 5 is displaced in the axial direction by the displacement of the different-diameter piston 3, thereby controlling the expansion deformation of the plurality of grip claws 4b by the taper portion 5a and the restoration of the deformation, and placing the collet 4 on the collet 4. The gripping and the gripping release are performed by pressing and releasing the pressure contact with the inner periphery of the gripping hole 401 formed in the center of the workpiece 400, for example.

In this case, in the collet 4 and the different diameter piston 3, the collet 4 is provided around the gripping pawl drive shaft 5.
And a working hole 4c penetrating the different diameter piston 3 in the axial direction.
Further, the work hole 3d is formed, and the work 400 held by the collet 4 can be machined from the back side. In addition, in the case of the present embodiment, as illustrated in FIG.
The work hole 3d of the different-diameter piston 3 has a substantially semi-circular shape including a plurality of work holes 4c on the collet 4 side, while having a circular shape that includes a necessary processing area as described later. Presents.

A seating confirmation air hole 4e is formed on the mounting surface of the work 400 in the collet 4, and the air supply hole 1j and the air supply hole 102 are formed in the cylinder body 1 and the main shaft 104. Is in communication with. Then, it is confirmed whether or not the work 400 is placed on the collet 4 by externally detecting a pressure increase in the air supply hole 102 when the seating confirmation air hole 4e is closed by the work 400 by a pressure switch or the like. It is a thing.

Further, an air blow air supply hole 103 is formed in the inner shaft direction of the main shaft 104, and by blowing pressurized air around the cylinder body 1, cutting that occurs during processing of the work 400 is performed. An operation is performed to actively remove dust and the like.

An example of the operation of the clamp device of this embodiment will be described below.

First, the cylinder body 1 is moved by the main shaft 104.
Is fixed with the mounting surface side of the collet 4 facing upward. At this time, by applying a pressurized fluid to the fluid chamber B of the different diameter cylinder 1d through the fluid passage 101b in the main shaft 104, the different diameter piston 3 moves the gripping pawl drive shaft 5 to the side closer to the collet 4. The plurality of grip claws 4b, which are moved to the side of projecting to the outside and are arranged around the tapered portion 5a of the grip claw drive shaft 5 in the collet 4, are contracted by the elasticity of the grip claws 4b.

With respect to the collet 4 in this state, a plurality of gripping claws 4b are inserted into the gripping hole 401 at the center of the work 400 by a robot hand (not shown) or the like, and a plurality of holes to be machined 402 of different types from each other. And the planned processing positions of the plurality of holes 403 are the working holes 4 of the collet 4.
The work 400 is placed on the collet 4 in a posture overlapping with c.

At this time, the collet 4 is moved by the work 400.
Since the seating confirmation air hole 4e opened at the position is closed, the internal pressure of the air supply hole 102 rises, and after detecting the increase in the internal pressure, the placement of the work 400 is confirmed, and then the different diameter is passed through the fluid passage 101a. The pressurized fluid acts on the fluid chamber A of the cylinder 1d to displace the different diameter piston 3 in the direction away from the collet 4, that is, in the direction in which the grip claw drive shaft 5 is pulled in. As a result, the plurality of gripping claws 4b are deformed by the tapered portion 5a of the gripping claw drive shaft 5 in a direction of expanding inside the gripping hole 401 of the work 400, and are pressed into the gripping hole 401. The work 400 is stably gripped and fixed to the collet 4 by the frictional force between the grip claw 4 b and the inner peripheral surface of the grip hole 401. FIG. 1 shows this state.

In the gripping state of FIG. 1, a pilot hole 402 on the side of the hole to be machined 402 from the front side of the collet 4 is drilled by a drill for drilling a pilot hole (not shown) located on the collet 4 side.
The drilling work of a is performed, and then the spindle 1 of the indexing board 100.
04 is rotated 180 degrees to a position where the protruding portion 111a of the stopper 111 abuts the positioning screw 113, the cylinder body 1 is inverted, and the head cover 2 is fixed in a posture in which it faces upward.

After that, the different diameter piston 3 and collet 4
From the back side of the collet 4 through the work hole 3d and the work hole 4c penetrating through the
3 prepared holes 403a.

In this way, the prepared holes 402a and 403 of the holes to be processed 402 and 403 are processed from both the front and back sides of the work 400.
After drilling 3a, the main shaft 104 is rotated again by 180 degrees so that the collet 4 faces upward.
Invert.

Then, the machining tool is switched from a drill for drilling a pilot hole to, for example, a screw cutting tool (not shown), and first, each of the holes 402 to be machined is drilled from the front side of the collet 4 as described above. The screw hole 402b is processed with respect to the prepared hole 402a.

After that, by rotating the main shaft 104 by 180 degrees, the cylinder body 1 is turned upside down, and the head cover 2 is turned upside down, from the back side of the collet 4 through the work hole 3d and the work hole 4c. Hole to be processed 4
03, each prepared hole 403a drilled as described above
Then, the screw hole 403b is processed.

Then, the main shaft 104 is rotated 180 degrees,
After the collet 4 and the work 400 are turned upside down, the pressurization of the different diameter cylinder 1d to the fluid chamber A is released, and at the same time, the fluid chamber B is pressed so that the gripping pawl drive shaft 5 projects to the outside. The pistons 3 having different diameters are moved in the direction to release the pressure contact state of the plurality of gripping claws 4b of the gripping claw drive shaft 5 with the inner circumference of the gripping hole 401 of the workpiece 400.

The machined work 400 whose gripped state by the collet 4 is released in this way is replaced with an unmachined work 400 by a robot hand (not shown) or the like, and the above-described series of machining operations are continuously performed.

As described above, according to the clamp device of the present embodiment, both front and back sides of the collet 4 that grips the work 400 are processed on both the front and back sides of the work 400 by complicated attachment and detachment of the work 400. The work can be continuously performed without requiring work, and the efficiency of the working work is significantly improved. In particular, when used for an automatic supply operation of the work 400 to an automatic machining machine such as a machining center having a function of automatically exchanging a plurality of kinds of tools, it is efficient in combination with an automatic tool exchanging function in the automatic machining machine. A machining process can be realized.

Further, the gripping pawl drive shaft 5 and the collet 4
However, since they are detachably connected to the different-diameter pistons 3 and the cylinder body 1, respectively, it is possible to easily and quickly deal with the change of the type of the work 400.

Further, the displacement of the grip claw drive shaft 5 for driving the plurality of grip claws 4b to open and close is sufficient to be, for example, about several mm. However, in such a short stroke different diameter piston 3, as in the conventional case. In the structure in which the groove is formed on the side of the different diameter piston 3 and the piston packing is mounted, the thickness dimension of the different diameter piston 3, that is, the axial dimension of the cylinder body 1 is increased by the amount of the piston packing. Inevitably, in the case of the present embodiment, as described above, since the piston packing 1f is arranged and housed on the inner peripheral side of the different diameter cylinder 1d, the thickness dimension of the different diameter piston 3 is set. ,
There is an advantage that the clamp device can be downsized because it can be made as thin as necessary according to a short required stroke.

Further, a fluid passage 101 for supplying / discharging a pressurized fluid to / from the fluid chambers A and B for driving the pistons 3 having different diameters.
a, 101b, and an air supply hole 10 for seating confirmation
2. The air-blowing air supply hole 103 and the like are collectively penetrated in the inner shaft direction of the main shaft 104 to form a structure in which a pressurized fluid, air, or the like is supplied from the rear end side of the main shaft 104. For example, compared to a structure in which a pipe or the like is connected to the cylinder body 1 from the outside, there is an advantage that the pipe or the like is not an obstacle and a work space around the cylinder body 1 can be widened.

[0046]

[Embodiment 2] FIGS. 4 and 5 are a schematic sectional view and a schematic plan view showing a main part of a clamp device according to another embodiment of the present invention.

In the case of the second embodiment, one end of the cylinder 4f is coaxially fixed to each of the working holes 4c formed in the collet 4, and the other end of the cylinder 4f has a different diameter. A working hole 3 formed at a corresponding position of the piston 3 so as to penetrate therethrough in the axial direction.
In the structure e, the pistons 3 having different diameters are relatively movably inserted so as not to restrain the axial displacement of the pistons 3.

As a result, the different diameter piston 3 is prevented from idling by the cylindrical body 4f supported on the collet 4 side, the parts such as the idling prevention pin 2b are omitted, and the structure is simplified. Cutting debris generated during processing is reliably discharged to the outside through the cylindrical body 4f without staying inside the different diameter cylinder 1d, so that maintenance management is simplified.

[0049]

[Embodiment 3] FIGS. 6 and 7 are a schematic sectional view and a schematic plan view showing a main part of a clamping device according to still another embodiment of the present invention.

In the case of the third embodiment, the different diameter piston 3
A large-diameter gripping claw drive shaft 5 having substantially the same diameter is screwed to the rod portion 3b on the collet 4 side of the collet 4 for axially penetrating inside the different-diameter piston 3 and the gripping claw drive shaft 5. Hole 3f
Further, the working hole 5c is formed substantially coaxially and with the same diameter.

In this case, for example, it is possible to secure a sufficiently large machining area from the front and back sides of the cup-shaped workpiece 400 with a bottom and to reliably discharge machining waste to the outside of the cylinder body 1. There are advantages.

[0052]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.
It is as follows.

According to the clamp device of the present invention, it is possible to obtain an effect that the work can be continuously processed on both the front and back sides without requiring complicated work such as setup change.

Further, according to the clamp device of the present invention, it is possible to obtain the effects that the structure and the maintenance management are simple, and the work can be continuously processed on both the front and back surfaces.

Further, according to the clamp device of the present invention, it is possible to obtain an effect that the front and back surfaces of the work can be continuously processed in a small occupied space.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a main part of a clamp device according to an embodiment of the present invention.

FIG. 2 is a plan view thereof.

FIG. 3 is a side view thereof.

FIG. 4 is a schematic cross-sectional view showing a main part of a clamp device according to another embodiment of the present invention.

FIG. 5 is a schematic plan view thereof.

FIG. 6 is a schematic cross-sectional view showing a main part of a clamp device according to still another embodiment of the present invention.

FIG. 7 is a schematic plan view thereof.

[Explanation of symbols]

 1 Cylinder body 1a Fluid passage 1b Fluid passage 1c Base 1d Different diameter cylinder 1e Packing groove 1f Piston packing 1g Rod packing 1h Rod packing 1j Air supply hole 2 Head cover 2a Packing 2b Idling prevention pin 3 Different diameter piston 3a Piston part 3c Rod part Rod part 3d Working hole (first working hole) 3e Working hole (first working hole) 3f Working hole (second working hole) 4 Collet 4a Through hole 4b Grip claw 4c Working hole (First working hole) 4d Fixed screw 4e Seating confirmation air hole 4f Cylindrical body 5 Grip claw drive shaft 5a Tapered portion 5b Screw 5c Working hole (second working hole) 100 Indexing board (indexing mechanism) 101a Fluid passage 101b Fluid passage 102 Air supply hole 103 Air blow air supply hole 104 Spindle 105 Aligning 106 Bearing 107 Gear 108 Gear 109 Rotary Actuator 110 Drive Shaft 111 Stopper 111a Projection 112 Positioning Screw 113 Positioning Screw 400 Work 401 Gripping Hole 402 Machining Hole 402a Prepared Hole 402b Screw Hole 403 Machining Hole 403b Pilot Hole A Fluid chamber (first fluid chamber) B Fluid chamber (second fluid chamber)

Claims (4)

[Claims] 1. A cylinder body fixed to a main shaft of an indexing mechanism, a cylinder having a large diameter portion and a small diameter portion formed to penetrate the cylinder body in a direction intersecting with the main shaft, and the different diameter cylinder. A collet, which is detachably fixed to one end of the cylinder and has a through hole in which a plurality of gripping claws for holding the workpiece by expansion and contraction deformation are planted around the collet, and the different diameter cylinder. A different-diameter piston that fits into the first and second fluid chambers and is inserted through the through-hole of the collet, and has an inner end portion detachably connected to the different-diameter piston and an outer end portion. Has a gripping pawl drive shaft formed with a taper portion for slidingly contacting the plurality of gripping pawls to control the expansion and contraction deformation, and the different diameter piston and the collet around the gripping pawl drive shaft. Drilled through in the direction At least one first working hole,
Alternatively, a second working hole formed by penetrating the different diameter piston and the grip claw drive shaft in the axial direction and the first and second fluid chambers are communicated with each other to supply and discharge a pressurized fluid. And a fluid passage that operates. 2. The inside of the first working hole that axially penetrates the different diameter piston and the collet has one end fixed to the collet side and the other end facing the different diameter piston. 2. A clamp device according to claim 1, wherein a cylindrical body that is movably inserted is connected to the cylindrical body, and the cylindrical body also functions as an idling prevention unit that prevents idling of the different diameter piston. 3. A packing groove for accommodating a piston packing is formed in an inner peripheral portion of the different diameter cylinder at a position separating the first and second fluid chambers. Or the clamp device according to 2. 4. The first and second fluid passages are centrally provided through the inside of the cylinder body and the spindle at a rear end portion of the spindle, and an external fluid pressure circuit is provided at an outer end portion of the spindle. The clamp device according to claim 1, wherein the clamp device is connected to the clamp device.