JP2000052174A - Work vice - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work vice capable of stably gripping a circular work, facilitating adaptation to a dimension change, and facilitating the correction of a holding position caused by claw wear without damaging the work. SOLUTION: A work vice is provided with a base 1 fixed to the table of a machine tool, two fixed claws 8 and one moving claw 15 disposed in the upper surface of the base at the interval of 120 deg. in the direction of radiation, fixing means 7, 12 and 13 for fixing the two fixed claws on the base 1 in the plurality of places of the direction of radiation, and a straight motion mechanism 22 for advancing/retreating the moving claw 15 in the direction of radiation. The fixed claws 8 and the moving claw 15 have tongue pieces 24 protruded in their tip lower parts for receiving the bottom surface of a work. In the base side upper part of each tongue piece 24, a gripping chip 27 made of cylindrical soft metal is fixed so as to be detached. The size of the work is dealt with a change in the fixing position of the fixed claw 8, and when the gripping chip 27 is worn, the fixing is slackened to rotate the gripping chip, and the work is gripped by an unworn portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work vise which is used to hold a work by fixing it to a table such as a drilling machine or a machining center. And a work vise which is particularly suitable for

[0002]

2. Description of the Related Art When machining the surface or end face of a disk-shaped or short cylindrical work with a machining center or a drilling machine, a fixture (a vise or a chuck) for fixing the work is attached to a table of a machine tool, and the fixing is performed. The work is fixed by gripping the outer periphery of the work with the claws of the tool.

[0003] The work fixture includes a fixed claw and a moving claw opposed to each other. A vice for gripping the work by moving the movable claw toward the fixed claw, and three claws arranged in a radial direction. There is a chuck that grips the work by simultaneously moving the work.In the case of a vise, in order to stably maintain the circular outer circumference, the width of the fixed claw is widened and the contact surface with the work is V-shaped. A structure in which three claws are simultaneously advanced and retracted in a radial direction by rotating a scroll disk provided with a spiral groove is used as a chuck (scroll chuck).
Is used.

[0004]

In the scroll chuck, three claws arranged at 120-degree intervals abut the three positions equally dividing the circumference of the work to grip the work, so that the work is stably fixed. However, since the internal structure is complicated, it is expensive, and the radial guide for guiding the claws and the spiral groove for opening and closing the claws are located directly below the workpiece, so these sliding parts are cut. In many cases, the claw cannot be opened and closed due to the bite of the powder, and in such a case, it is necessary to disassemble and clean the chuck, and there is a problem that the maintenance work is troublesome.

On the other hand, even if the vise has a structure in which the contact surface with the work is V-shaped, the holding force against the external force in the direction of tilting the work is weak, and if the holding force is increased, the claw width is reduced. A problem arises that the size must be very large and the claws must be replaced according to the size of the work.

Further, when the outer periphery of a circular work is clamped by such a vice or chuck, the contact between the work and the claw is in linear contact, so that when the work is strongly gripped or when the gripping force of the work is weak, the work is performed. There is a problem that when the work moves during the operation, the claws damage the outer periphery of the work.
This problem can be avoided by using a raw claw, that is, a claw that clamps the work by processing the tip of the claw according to the outer periphery of the work. However, when processing a small lot, the claw tip is processed one by one according to the work. It is difficult to use a soft metal at the tip of the nail, and when the tip of the nail is worn, the holding position of the workpiece changes.To avoid this, the nail must be replaced frequently. There was a problem.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the conventional vise and chuck, and can stably clamp the outer periphery of a disk-shaped or short cylindrical work, and reduce the size of the work. It is an object of the present invention to provide a work vice that can easily cope with a change and that can easily restore a work holding position when a tip of a nail is worn without damaging the work.

[0008]

A work vise according to claim 1 comprises a base 1 fixed to a table of a machine tool,
Two fixed claws 8 and one movable claw 15 radially arranged on the upper surface of the base at intervals of 120 degrees from each other.
And fixing means 7, 12, 13 for fixing the two fixing claws to the base 1 at a plurality of positions in the respective radial directions, and a linear motion mechanism 22 for moving the moving claws 15 in the radial direction. It is a feature.

According to a second aspect of the present invention, in the work vise according to the first aspect, the fixed claw 8 and the movable claw 15 are provided with a protruding tongue piece 2 for receiving a bottom surface of the work at a lower portion of the tip.
4 and a partial cylindrical concave surface 25 located on the upper part of the tongue.
A gripping tip 27 made of a cylindrical soft metal having a radius of curvature equal to the radius of curvature of the concave portion of the partial cylinder is provided on the upper portion of the base of the tongue piece 24 so that the outer peripheral surface and the concave portion of the partial cylinder are in close contact with each other. And is detachably fixed.

[0010]

The disk-shaped or short-cylindrical workpiece is fixed with its outer periphery gripped by three claws arranged in the radial direction. Since the three claws are arranged at an angular interval of 120 degrees, the fixed claw 8 is fixed to the base 1 at any one of a plurality of fixed positions, so that the work can be carried out regardless of the diameter of the work. The workpiece can be gripped at three points close to the interval of about 120 degrees, and the grip of the work is stabilized. The size of the work can be adjusted by adjusting the position where the fixed claw 8 is fixed on the base 1 and the position where the movable claw 15 is moved forward and backward, so that the setup operation when the size of the work is changed can be quickly performed. As the linear motion mechanism 22, a feed screw or a hydraulic cylinder can be used.

As the material of the gripping tip 27, brass or aluminum is suitable from the viewpoint of the difference in hardness from iron and the price. The outer periphery of the work is gripped and fixed by the gripping tip 27. Since the gripping tip is made of soft metal, the outer peripheral surface of the work can be prevented from being damaged. The gripping reaction force acting on the gripping tip 27 is transmitted to the claws 8 and 15 by the close contact between the outer periphery of the gripping tip and the partial cylindrical concave surface 25 at the tip of the nail. When the contact portion of the gripping tip 27 with the workpiece is worn, loosening the fixation of the gripping tip to the tip of the claw and rotating the gripping tip allows the workpiece to be fixed at the unworn portion. Become. When the outer periphery of the gripping tip is completely worn, the gripping tip is replaced. The tongue piece 24 extends with a length exceeding the diameter of the gripping tip 27, and the work to be fixed has its tongue piece 3
4 is fastened while being supported by the tip.

[0012]

Embodiments of the present invention will be described below with reference to embodiments shown in the drawings. The base 1 is in the form of a square thick plate, and has cutouts at its four bottoms for clamping to a machining center.
A U-shaped notch 2 is provided for inserting a bolt for fixing the bolt to a table of a machine tool. A center hole 3 penetrating vertically is provided at the center of the base 1. Base 1
The upper surface is provided with three grooves at an angle of 120 degrees to each other in a radial direction about the center of the center hole, and two of the three grooves are inserted from the bottom surface of the base 1. The fixed claw holder 5 is fixed in a state of being fitted and inserted into the groove by the bolt 4 thus formed. The fixed claw holder 5 has a longitudinal T-shaped groove 6 opening on the upper surface, and a number of unevenness 7 in the width direction on the upper surface.
Are formed.

The fixed claws 8 are fixed to the upper surfaces of the two fixed claw holders 5, respectively. The lower surface of the fixed claw 8 is provided with unevenness that fits into the unevenness 7 on the upper surface of the fixed claw holder 5, and two bolt insertion holes 11 are provided. The fixed claw 8 is fixed to the fixed claw holder 5 by screwing the tip of the bolt 12 inserted into the bolt insertion hole 11 into the T-shaped nut 13 inserted into the T-shaped groove 6 of the fixed claw holder and fastening. At this time, the unevenness of the upper surface of the fixed claw holder and the unevenness of the lower surface of the fixed claw are fitted, and the position of the fixed claw 8 in the radial direction with respect to the base 1 is firmly fixed. If the bolt inserted into the bolt insertion hole 11 of the fixed claw is loosened and the fixed claw 8 is lifted to disengage the fixed claw holder from the unevenness 7, the radial position of the fixed claw holder 5 can be moved. The fixed claw 8 can be fixed to the fixed claw holder 5 at an optimum position according to the diameter of the work to be gripped.

A movable claw holder 14 is slidably fitted in the remaining one groove at a position facing the two fixed claws 8 along the groove. The groove to which the movable claw holder 14 is attached penetrates to the center hole 3 of the base, and the movable claw holder 14 can move to a position protruding from the center hole 3.
The movable claw holder 14 has the same claw fixing structure as the fixed claw holder 5, and the same movable claw 15 as the fixed claw 8 is used as the movable claw 15 fixed thereto. In other words, the moving claw 15 is configured such that the tips of the bolts inserted into the bolt insertion holes 17 of the moving claw with the unevenness 16 formed in the width direction of the moving claw holder 14 and the unevenness on the bottom surface of the moving claw 15 are fitted. By screwing and fastening to a T-shaped nut 20 inserted in a T-groove (not shown) of the holder, the movable claw 15
4 is fixed to the upper surface. As with the fixed claw 8, the fixed position of the movable claw 15 on the movable claw holder 14 can be changed by changing the fitting position of the unevenness. The T-shaped groove of the movable claw holder 14 is open on the distal end side (the center side of the base 1), and an engagement portion 18 with the distal end of a feed screw described later is provided on the outer diameter end.

When processing the raw claw with the fixed claw 8 and the moving claw 15, the moving claw holder is fixed by bolts 9 inserted from the bottom surface of the base. When adjusting the vertical position of the movable claw holder 14, the shim interposed between the movable claw holder and the bottom surface of the groove is moved up and down by screws 10 arranged on both sides of the bolt 9.

On the extension of the groove into which the movable claw holder is inserted, a flat U-shaped screw block 19 is fixed to the base 1 with bolts 21. A feed screw 22 is screwed into a screw hole of the screw block 19, The leading end of the feed screw is rotatably engaged with the engaging portion 18 of the movable claw holder 14 and cannot move in the axial direction. The protruding end of the feed screw 22 has a hexagonal member 2
By rotating the hexagonal member 23 with a wrench or the like, the feed screw 22 can be advanced and retracted, and the movable claw holder 14 can be advanced and retracted toward the center of the two fixed claws 8. .

Below the fixed claw 8 and the movable claw 15,
A tongue piece 24 extending in a flat U-shape is formed, and the top surface of the tip of each tongue piece is a receiving surface for receiving a work. Tongue piece 2
4 has a vertical partial cylindrical concave surface 25
A screw hole 26 that penetrates the tongue piece 24 is provided at a portion of the cylindrical concave surface through which the central axis passes.
A short cylindrical gripping tip 27 made of brass is fixed to an upper portion on the base side of the tongue piece 24 with a screw 28 inserted into the center hole thereof. There is a clearance between the center hole of the gripping tip 27 and the outer diameter of the screw 28. When the workpiece is gripped by three claws, the gripping tip 27 slides slightly on the tongue piece 24 due to the gripping reaction force. The outer peripheral surface of the gripping tip 27 and the partial cylindrical concave surface 25 at the tip of the claw come into close contact with each other. The workpiece is fixed in a state where its three outer peripheral surfaces are gripped by the outer peripheral surfaces of the three gripping tips 27.

At the position between each of the three claws on the upper surface of the base 1, an auxiliary claw 31 having a long hole in the radial direction is provided.
2 is fixedly mounted on the base 1 with one bolt 33 penetrating therethrough. The auxiliary claw 31 is provided for auxiliary positioning of the outer periphery of the work when the diameter of the work is large.

The work vice having the above structure is fixed to a table of a machine tool by bolts inserted into the notches 2 of the base, and
The fixed claw 8 and the single moving claw 15 are fixed to appropriate positions of the fixed claw holder 5 and the moving claw holder 14 according to the size of the work, and the moving claw 15 is advanced and retracted by the feed screw 22, and Are supported at the three positions by the tips of the tongue pieces 24 of the three claws, and the workpiece thus supported is moved forward by the feed screw 22 to move the moving claws 15 so as to grasp and fix the outer three positions. The fixing positions of the two fixing claws 8 on the fixing claw holder 5 are determined so that the outer periphery of the work comes into contact with the gripping chip 27 at three positions at an angle close to 120 degrees.
The gripping tip 27 is made of brass and is softer than iron.Therefore, there is a possibility that the gripping tip 27 may be worn by repeatedly gripping the work. The work can be gripped on the surface that is not worn.

[Brief description of the drawings]

FIG. 1 is a perspective view of a work vise of the present invention as viewed from above.

FIG. 2 is a perspective view of the work vise of the present invention as viewed from below.

FIG. 3 is a sectional view of the moving holder and the moving claw of FIG. 1;

[Explanation of symbols]

 1 Base 7 Irregularity 8 Fixed claw 12 Bolt 13 T-slot 15 Moving claw 22 Feed screw 24 Tongue piece 25 Partially cylindrical concave surface 27 Gripping tip

Claims (2)

[Claims] 1. A base fixed to a table of a machine tool
(1) and two fixed claws (8) and one movable claw (15) radially arranged on the upper surface of the base at an interval of 120 degrees from each other, and two fixed claws. Fixing means (7, 12, 13) for fixing on the base (1) at a plurality of positions in the radial direction,
A work vise including a linear motion mechanism (22) for moving the movable claw (15) in a radial direction. 2. A fixed tongue (8) and a movable tongue (15) each having a protruding tongue piece (24) at a lower end portion thereof for receiving a bottom surface of a work.
And a cylindrical soft metal having a partial cylindrical concave surface (25) located on the upper part of the tongue piece, and having a radius of curvature equal to the radius of curvature of the partial cylindrical concave surface at the base upper side of the tongue piece (24). The work vise according to claim 1, wherein the gripping tip (27) is detachably fixed with its outer peripheral surface and the partial cylindrical concave surface in close contact with each other.