JP2008068351A - Workpiece holder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a workpiece holder for fixedly holding a workpiece with a working surface as reference, releasing the holding of the workpiece while a holding part is fixed, and preventing a gap from occurring between a movable region of the holding part and concave and convex surfaces of a fixed region even if the fixing of the holding part is released. <P>SOLUTION: The workpiece holder has at least one of a pair of holding parts linearly moving toward the other holding part for holding the workpiece. The holding part includes: the movable region 4 having a convex surface 5c on an opposite surface to a surface in contact with the workpiece; the fixed region 7 for holding the convex surface of the movable region by a concave surface 8c with an approximately same diameter; and a supporting shaft 10 for supporting the movable region and the fixed region. Spherical surfaces facing the movable region and the fixed region, are tightly fixed by bringing back and forth a clamp block 11 engaging with the movable region by movement of the supporting shaft, causing the workpiece to be fixedly held on the surface of the movable region in contact with the workpiece. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a workpiece gripping apparatus.

  When cutting a metal or a resin with a machine tool such as a milling machine, a gripping device such as a vise (vise) is installed on the table of the machine tool, and the workpiece is gripped and processed by the gripping device.

  In a conventional workpiece gripping device, a workpiece is gripped and fixed between a pair of facing surfaces, and a rotating ball having a contact plane is rotatably provided on one or both of the facing surfaces ( Patent Document 1) and two clamping parts for clamping a workpiece, and at least one of the two clamping parts changes its direction around at least one axis with respect to the fixed part and the fixed part. There is disclosed a workpiece holding device (Patent Document 2) that is configured as a combination block composed of movable parts that can be formed, and whose opposing surfaces of the movable part and the fixed part are spherical surfaces.

In the workpiece gripping device described above, the gripping part that grips the workpiece can freely change its direction with its concave and convex spherical surfaces, and can grip workpieces of various shapes. At the time of gripping an object, no attention is paid to gripping the workpiece with respect to the processing surface. If the machined surface is not perpendicular to the tool to be machined, there will be a difference in the thickness of the workpiece after machining, not only will it look bad, but it cannot be used as a product. In order to solve this problem, there has been a problem that the angle of the processing surface with respect to the tool to be processed must be adjusted each time one material is processed.
Further, in the above gripping device, the workpiece gripped during processing may move unexpectedly. For example, when a load is applied to the work surface by a tool or the like that is processed during cutting, the work surface of the workpiece may continue to be tilted, making it difficult to ensure the accuracy of the work surface. Become.

  In the above gripping device, a gap is generated between the concave and convex spherical surfaces of the member that grips the workpiece when the workpiece is released. Grinding accuracy of the workpiece, such as machining chips get into the gap between the concave and convex spherical surfaces and the concave and convex spherical surfaces are not in close contact when the workpiece is gripped next, or the concave and convex spherical portions are difficult to move freely. There was a problem that decreased.

Moreover, in said holding | grip apparatus, the fixation of the fixed part and movable part which were being fixed by the uneven | corrugated spherical surface of a holding part will also be cancelled | released simultaneously with cancellation | release of a holding | grip. When a plurality of workpieces having the same shape are continuously processed, repeated gripping at the same position is impossible, and it is necessary to adjust the angle of the processing surface of the workpiece and grip it each time processing is performed.
Japanese Patent No. 8-309670 JP-A-2005-14121

  The present invention has been made to cope with such problems. The workpiece is gripped and fixed on the basis of the machining surface, and the workpiece is released from being held in a state where the fixed portion of the gripping portion and the movable portion are fixed. An object of the present invention is to provide a workpiece gripping device in which no gap is generated between the convex spherical surface of the movable part of the gripping part and the concave spherical surface of the fixed part even if the gripping part is released from being fixed.

  The workpiece gripping device of the present invention is a workpiece gripping device in which at least one pair of gripping portions linearly moves in the direction of the other gripping portion to grip the workpiece, and the gripping portion includes: A movable portion having a convex spherical surface on a surface opposite to the surface in contact with the workpiece; a fixed portion that holds the convex spherical surface of the movable portion with a concave spherical surface having substantially the same diameter; and a support shaft that supports the movable portion and the fixed portion. And the fixed part has the support shaft penetrating from the opposite surface of the concave spherical surface, and the movable part has the convex spherical surface and is formed on the surface opposite to the convex spherical surface. A base member having a recess, a clamp block that engages with the recess, and a gripping member that covers and fixes the recess of the base member in which the clamp block is movably incorporated. The surface is a spherical surface that is concentric with the convex spherical surface and has a smaller diameter than the convex spherical surface. The clamp shaft is fixed to the tip of the support shaft, the clamp block engages with a concave spherical recess of the movable part, and the support shaft penetrates the movable part and the fixed part. Thus, both the parts are supported, and the support shaft is advanced and retracted to tightly fix the opposing spherical surfaces of the movable part and the fixed part, and the work piece is held on the surface of the movable part in contact with the work piece. It is characterized by holding and fixing.

  The fixing part is arranged on the opposite surface of the fixing member having the concave spherical surface and the concave spherical surface of the fixing member, and is screwed into a polygonal bolt inserted perpendicularly from the side surface of the fixing member. A slide member that advances and retreats in the axial direction of the bolt and has a slope surface in the axial direction, and a slope surface that engages with the slope surface of the slide member. A block member that moves in a direction perpendicular to the advancing and retreating direction, and the fixing member, the slide member, and the block member are connected by passing through the support shaft, and the polygon bolt is turned, The support shaft is advanced and retracted by interlocking the slide member and the block member screwed to the polygonal bolt, and the movable portion and the fixed portion are fixed by the advance and retreat of the clamp block engaged with the movable portion. The position of the opposing spherical and closely fixed, characterized in that gripping fixing a workpiece in a surface in contact with the workpiece gripping members movable portion.

  The fixed part has a fixing member having the concave spherical surface, and a polygonal bolt connected by screwing in the axial direction of the support shaft from a rear end portion of the support shaft passing through the movable part and the fixed part. Then, the support shaft is advanced and retracted by turning the polygonal bolt, and the movable portion and the fixed portion are fixed in close contact with each other by the advance and retreat of the clamp block engaged with the movable portion. The workpiece is gripped and fixed on the surface of the gripping member in contact with the workpiece.

In order to grasp the processed surface of the work piece as a reference, the upper surface or the side surface of the fixed portion has a portion in contact with the reference portion of the work piece.
The rotation angle of the clamp block is regulated by a gap with the clamp block formed in the recess of the base member.

The movable part is freely movable within a restricted range without generating a gap between the spherical surfaces of the movable part and the fixed part when the workpiece is released.
The movable portion has a plurality of springs on the lower surface thereof, and when the workpiece is released, the movable portion is returned to the original position by a spring force.

The workpiece gripping device of the present invention includes a movable part having a convex spherical surface on a surface opposite to a surface in contact with the workpiece, and a concave part having a substantially identical diameter on the convex spherical surface of the movable part. A support shaft that fixes a fixed portion held by a spherical surface to a distal end of a clamp block that engages with the movable portion supports the movable portion and the fixed portion. For this reason, it is possible to freely change the angle of the surface in contact with the work piece at each spherical surface while the movable part is supported by the support shaft with respect to the fixed part, and it can be gripped regardless of the shape of the work piece. Is possible.
Further, the slide shaft and the block member of the fixed part are interlocked to advance and retract the support shaft, or the polygon shaft bolted directly in the axial direction from the rear end portion of the support shaft is rotated to advance and retract the support shaft. As a result, the clamp block fixed to the tip of the support shaft and engaged with the movable part is advanced and retracted, and the spherical surfaces facing the movable part and the fixed part are closely fixed. By this tight fixation, the surface of the movable member that contacts the workpiece can be firmly fixed in a state where the angle along the shape of the workpiece is maintained, and the workpiece can be firmly held and fixed.
Further, the gripping of the workpiece can be released in a state where the movable part and the fixed part of the gripping part are closely fixed. That is, the gripping portion can be separated from the processed workpiece while maintaining the angle of the surface of the gripping portion in contact with the workpiece, and the workpiece can be gripped again at the same angle. For this reason, it is possible to hold | grip the workpiece of the same shape continuously.
Further, in the gripping device in which the polygonal bolt is disposed on the opposite surface of the concave spherical surface of the fixing member, the gripping device can be further reduced in size and can be used for gripping precision members.

  Since the upper surface or the side surface of the fixed portion has a portion in contact with the reference portion of the workpiece, the workpiece can be gripped and fixed with reference to the processing surface of the workpiece, and offset gripping can be prevented. Further, even when a load is applied to the work piece by the tool at the time of cutting by the machine tool, it is possible to perform the processing without causing the processing surface to be inclined.

When releasing the fixing of the gripping part, it is possible to change the angle of the surface in contact with the workpiece while being supported by the support shaft between the convex spherical surface of the movable part of the gripping part and the concave spherical surface of the fixed part. , No gap occurs between the concave and convex spherical surfaces. For this reason, processing chips do not enter between the spherical surfaces, and the gripping accuracy of the gripping device can be used without lowering.
Further, the rotation angle of the clamp block is regulated by a gap with the clamp block formed in the recess of the base member.
From the above, the angle around the axis of the support shaft can be changed without pinching foreign matter such as chips generated during cutting between the convex spherical surface of the clamp block and the concave spherical surface of the fixed part. The angle can be changed freely in any direction. Furthermore, by having a part that regulates the rotation angle, it is possible to keep the rotation angle of the movable part relative to the fixed part to the minimum necessary size.
Further, the movable member can be returned to the original position even if the holding portion is released by the spring installed on the lower surface of the movable member.

  An example of the workpiece gripping device will be described with reference to the drawings. FIG. 5 is a diagram for explaining the outline of the workpiece gripping device, and FIG. 6 is a perspective view for explaining the workpiece gripped by the workpiece gripping device. FIG. 7 is a perspective view for explaining an embodiment of the workpiece gripping apparatus.

  A workpiece gripping device (hereinafter, referred to as a gripping device) 1 of the present invention has a pair of gripping portions, and at least one gripping portion linearly moves in the direction of the other gripping portion, and between the pair of gripping portions. Is a gripping device for gripping a workpiece. Specifically, as shown in FIG. 5, the movable grip portion 2a is fixed to the drive screw 3a of the linear drive screw portion 3 via the screw fixing portion 3b, and is driven on the sliding portion 22 in the direction of the fixed grip portion 2b. It is linearly moved by screw rotation of the screw 3a. The gripping device 1 is installed and used on a table of a machine tool such as a milling machine.

  As shown in FIG. 6, the workpiece 21 to be gripped by the gripping device is perpendicular to the processing surface on the back surface of the processing surface (21a and 21b in FIG. 6B) of the workpiece to be actually processed. In addition, a rib portion 21c that is a portion to be gripped is provided in advance by welding or the like. Both sides of the rib portion are gripped by a pair of gripping portions of the gripping device. FIG. 7 shows a state where the workpiece 21 is actually gripped by the gripping device 1. As shown in FIG. 7, the gripping device 1 fixed on the table of the machine tool grips the rib portion 21c of the workpiece with the gripping portions 2a and 2b, and processes the surface of the processing surface 21a or 21b of the workpiece. To do.

  As shown in FIGS. 5 and 7, when the workpiece 21 is gripped, the workpiece 21 is placed between the pair of gripping portions 2a and 2b of the gripping device 1, and the drive screw 3a is turned to move the movable gripping portion 2a. Are linearly moved along the groove of the sliding portion 22 in the direction of the fixed holding portion 2b, and the rib portion 21c of the workpiece is temporarily clamped between the pair of holding portions. Thereafter, the angle of the surface of the grip portion 2 that contacts the workpiece is adjusted and fixed, and the workpiece is gripped and fixed.

  An example of an embodiment of the grip part 2 of the grip device 1 of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a grip portion of a workpiece gripping device according to an embodiment of the present invention. FIG. 2 is an assembled perspective view of the gripping portion viewed from the side of gripping the workpiece, and FIG. 3 is an assembled perspective view of the gripping portion viewed from the opposite side.

  As shown in FIG. 1, the grip portion 2 has a movable part 4 having a convex spherical surface on the opposite surface to the surface in contact with the workpiece, and a fixed spherical surface 5c that holds the convex spherical surface 5c of the movable part 4 with a substantially identical diameter. The part 7 is supported by a support shaft 10 (not shown) penetrating both members. The movable part 4 is processed along the spherical surface with the support shaft 10 penetrating and supporting the movable part 4 and the fixed part 7 without having a gap between the spherical parts of the movable part 4 and the fixed part 7. It is a structure that can move by changing the angle of the surface in contact with the object.

In addition, as shown in FIG. 1, the movable part 4 and the fixed part 7 form substantially the same surface on the upper surface, but the vertical length of the movable part 4 that faces the fixed part 7 with its concave and convex spherical surfaces faces each other. It is shorter than that of the fixing part 7. Since the gap is provided between the lower side of the movable part 4 and the sliding part 22 where the grip part 2 of the gripping device 1 moves linearly, the movable part 4 changes the angle of the surface to be gripped with respect to the fixed part 7. Can move.
In addition, the grip portion 2 can be used for either one or both of the pair of grip portions 2 of the grip device 1. When the gripping part is used as the movable gripping part 2a, it is connected to the linear drive screw part 3 shown in FIG.

  The structure of the holding part 2 will be described in detail with reference to the drawings. As shown in FIG. 2, the grip portion 2 supports the movable portion 4 and the fixed portion 7 through the support shaft 10.

  The fixed part 7 is fixed to the movable part 4 on a fixed member 8 having a concave spherical surface 8c having substantially the same diameter as the convex spherical surface 5c of the base member 5 of the movable part 4 and the opposite surface of the concave spherical surface 8c of the fixed member 8. Members for advancing and retreating the support shaft 10 that penetrates and supports the portion 7 are arranged in combination. Specifically, as shown in FIGS. 2 and 3, a polygonal bolt 14 is screwed perpendicularly from the side surface through a washer 15 to a fixing member 8 having a cut-out corner including the side surface opposite to the concave spherical surface 8 c. The auxiliary member 16 to be inserted is engaged. The auxiliary member 16 has a U-shaped cutout portion 16c on the side of the fixed member 8 that is engaged. A slide member 17 and a block member 18 that are engaged with each of the inclined surfaces are combined and inserted into the U-shaped cutout portion 16c.

As shown in FIGS. 2 and 3, the slide member 17 is a plate-like member having a notched surface with a slope on a part of one side. Further, notched holes 17b and 17c each having a length in the length direction of the member are formed in a portion with the notched surface and a portion without the notched surface, respectively. On the other hand, the block member 18 is a plate-like member having a sloped surface that engages with the sloped cutout surface of the slide member 17.
These members are inserted into the notch portion 16c of the auxiliary member 16 with the slide member 17 side in an engaged state by surface contact with the inclined surfaces facing each other. At this time, the slide member 18 is inserted so as to be on the fixed member 8 side. 5 is inserted into the hole 16b of the auxiliary member 16 through the notch hole 17b of the slide member 17 from the hole 8b on the concave spherical surface 8c side of the fixing member 8 by the screw 9c, and further screw fixing of the linear drive screw portion 3 shown in FIG. It is fixed to the part 3b. Further, the holes 16d and 16e on the auxiliary member 16 side are fixed to the holes 8d and 8e of the fixing member 8 by screws 9d and 9e, respectively.

  As shown in FIGS. 2 and 3, a hole 17a penetrating into the hole of the cutout hole 17b is formed in the surface of the slide member 17 on the side inserted into the auxiliary member 16. The polygonal bolt 14 is screwed through a washer 15 into a hole 16a in which a female thread is cut from a side surface of the auxiliary member 16 into a cutout portion 16c into which the slide member 17 is inserted. Furthermore, the tip end portion of the polygonal bolt 14 is screwed into the hole 17 a of the slide member 17. By turning the polygonal bolt 14, the slide member 17 can be drawn toward the polygonal bolt 14 side along the notch portion of the auxiliary member 16 by the screw rotation of the polygonal bolt 14. By rotating in the reverse direction, the slide member 17 can be moved in the straight direction of the polygonal bolt 14 by the amount of screw rotation.

  In addition, the tip of the support shaft 10 that penetrates and supports the movable part 4 and the fixed part 7 is provided with a hole 18a that penetrates the block member 18 and a hole 17c that penetrates the gradient surface of the slide member 17 that is in surface contact with the gradient surface. And is inserted into a hole 8 a that penetrates the fixing member 8. The rear end portion of the support shaft 10 is fixed to the block member 18 with screws 12b. Further, the rear end portion of the support shaft 10 has a repellent material 13. As the rebound material 13, a cushion member, a spring, or the like, which is an elastic member, can be used. The support shaft 10 is further in contact with the screw fixing portion 3b of the linear drive screw portion 3 shown in FIG. The support shaft 10 is always urged by the repulsive material 13 in the direction of the surface in contact with the workpiece.

  The movable part 4 has a base member 5 having a concave spherical recess 5d formed on the surface opposite to the convex spherical surface 5c, a clamp block 11 engaged with the recess 5d, and the clamp block 11 engaged with the movable member 4. The gripping member 6 is a member that covers the side and is fixed to the base member 5 and that grips the workpiece in direct contact with the workpiece.

  As shown in FIG. 2, the base member 5 has a convex spherical surface 5 c that is cut off in the upper, lower, left and right directions. The convex spherical surface 5c faces the concave spherical surface 8c of the fixing member 8 of the fixing portion 7 having substantially the same diameter. Further, the base member 5 has a spherical recess 5d that is concentric with the convex spherical surface 5c and has a smaller diameter than the convex spherical surface 5c on the surface opposite to the convex spherical surface 5c, that is, the gripping member 6 side. The hole 5a passes through the center of 5d. The support shaft 10 passes through the hole 5a, and the clamp block 11 is engaged with the recess 5d.

  The clamp lock 11 is a member having a fan-like thickness in which a part of a circular arc is cut out. The recess 5d formed on the opposite surface of the convex spherical surface 5c of the base member 5 of the movable part 4 with which the clamp block 11 is engaged also has a fan-like shape having a portion cut out in a part of the circular arc of the circumference of the recess. Shape. Both members engage with each other at the cutout portions of both members. The clamp block 11 fitted and engaged with the recess 5d of the base member 5 is fixed to the distal end portion of the support shaft 10 with screws 12a.

The engaging surfaces of the clamp block 11 and the recess 5d of the base member 5 with which the clamp block 11 engages are a convex spherical surface and a concave spherical surface, respectively, having substantially the same diameter. The concave and convex spherical surface is concentric with the convex spherical surface 5c of the movable part 4 and the concave spherical surface 8c of the fixed part 7, and has a smaller diameter than the spherical surfaces of the movable part and the fixed part. The diameter of the clamp block 11 is smaller than the diameter of the recess 5 d of the base member 5, and the diameter of the hole 5 a through which the support shaft 10 of the base member 5 passes is larger than the diameter of the support shaft 10.
After the clamp block 11 is engaged, the holes 6a and 5b are fixed to the opposite surface of the convex spherical surface 5c of the base member 5 with screws 9a as shown in FIG. This gripping member 6 is a member that actually contacts the workpiece. The gripping member 6 is fixed so as to cover the recess 5 d of the base member 5.

With the above structure, the movable part 4 can change the angle around the axis about the support shaft 10 without having a gap between the spherical surfaces with respect to the fixed part 7, as well as up, down, left, right, and The angle can be freely changed in the direction.
In addition, the clamp block 11 is movably built in the recess 5d of the base member 5 of the movable portion 4 while having a gap. This gap regulates the rotation angle of the clamp block. As the volume of the gap increases, the movable range of the clamp block 11 inside the recess 5d of the base member 5 becomes wider, and the angle of the movable part 4 to be engaged with the fixed part 7 can be increased. On the contrary, the smaller the volume of the gap, the narrower the movable range of the clamp block 11 inside the recess 5d of the base member 5, and the smaller the angle of the movable part 4 to be engaged with the fixed part 7 is. From these things, it becomes easy to regulate the movement in which the support shaft 10 changes the angle of the movable part 4 with respect to the fixed part 7. Further, the movable part 4 can be moved with respect to the fixed part 7 within a sufficient angle range for gripping the workpiece. However, after the gripping part is fixed, the movable part 4 is assumed to be relative to the fixed part 7. It is possible to prevent the movement that changes the outside angle from occurring, and it is possible to grip securely and firmly.

  When the workpiece is actually gripped by the gripping device 1 of the present invention, the position where the movable portion 4 is horizontal to the fixed portion 7 with respect to the fixed portion of the surface of the movable portion 4 that grips the workpiece (this position) Can be moved up to 3 degrees in each direction in all directions.

  Further, as shown in FIG. 2, a spring 20 is installed below the movable part 4. A pair or a plurality of lower portions of the springs 20 are installed in the lower portion of the movable portion 4 so that the grip portion 2 of the grip device 1 contacts the sliding portion 22 that moves linearly. When the close contact is released on the spherical surfaces of the movable portion 4 and the fixed portion 7, the movable portion 4 can return to the origin by the spring force of the spring 20.

  In the gripping device 1, the workpiece 21 is temporarily clamped between the pair of gripping portions 2, and the movable portion is further moved relative to the fixed portion 7 of the gripping portion 2 along the shape of the gripping surface of the workpiece 21. By changing the angle of the surface in contact with the workpiece 4 and fixing the movable portion 4 and the fixed portion 7, the workpiece 21 is firmly held and fixed.

  A mechanism for fixing the movable part 4 of the grip portion 2 to the fixed part 7 will be described. This is fixed when the convex spherical surface of the movable part 4 is in close contact with the concave spherical surface of the fixed part 7. FIG. 4 is a cross-sectional view for explaining a mechanism in which the movable part 4 and the fixed part 7 are fixed and released, as viewed from the upper surface of the grip portion 2. In order to simplify the explanation in FIG. 4, the side to grip the workpiece is the A side, the opposite side is the B side, and the direction from the A side to the B side in the axial direction of the support shaft 10 is “B The direction from the B side to the A side is the “direction to the A side”.

  As shown in FIG. 4A, when the movable portion 4 is not fixed to the fixed portion 7, a gap is generated between the convex spherical surface 5c of the base member 5 and the concave spherical surface 8c of the fixed member 8. Although not closely attached, the movable part 4 is supported by the support shaft 10, and the angle of the surface to be gripped with respect to the fixed part 7 can be changed. Further, the engagement surfaces 11c and 5d of the base member 5 of the movable block 4 and the clamp block 11 are not in close contact with each other as well as between the spherical surfaces.

  From this state, as shown in FIG. 4B, the polygonal bolt 14 on the side surface of the auxiliary member 16 at one corner of the fixing portion 7 is rotated clockwise with a spanner or the like. As a result, the slide member 17 screwed into the polygonal bolt 14 moves along the notch portion of the auxiliary member 16 in the direction toward the polygonal bolt 14 by the amount of screw rotation of the polygonal bolt 14. Further, the block member 18 that comes into surface contact with the gradient surface of the slide member 17 moves in the direction toward the B side on the gradient surface by the movement of the slide member 17. As the block member 18 moves, the support shaft 10 also moves in the direction of the B side together with the block member 18 fixed with screws, and accordingly, the clamp block 11 screwed to the tip of the support shaft 10 is also B Move in the direction of the side. Accordingly, the base member 5 to be engaged is pulled toward the B side, and the convex spherical surface 5c of the base member 5 and the concave spherical surface 8c of the fixing member 8 are brought into close contact with each other and fixed.

  On the other hand, when releasing the above-mentioned fixation, as shown in FIG. 4C, the slide member 17 moves in the straight direction of the polygonal bolt 14 by turning the polygonal bolt 14 counterclockwise. Move to the screw rotation. Here, the support shaft 10 and the clamp block 11 are also moved in the A side direction by the biasing force in the A side direction of the repellent material 13 with which the rear end portion of the support shaft 10 fixed to the block member 18 abuts. The close contact between the convex spherical surface 5c of the base member 5 and the concave spherical surface 8c of the fixing member 8 is released.

  Moreover, another embodiment of the gripping device of the present invention will be described with reference to the drawings. FIG. 8 is a top cross-sectional view illustrating another embodiment of the gripping portion, in which FIG. 8A is a cross-sectional view of the gripping portion 2 of the present invention described above, and FIG. 8B is another cross-sectional view of the present invention. It is sectional drawing of holding | grip part 2 'which shows embodiment. FIG. 9 is a side sectional view of the workpiece gripping apparatus 1 for explaining an embodiment of the gripping portion 2 ′.

As shown in FIG. 8 (b), the gripping part 2 ′ has a movable part 4 having a convex spherical surface on the opposite surface to the surface in contact with the workpiece, and the convex spherical surface of the movable part 4 is a concave spherical surface having substantially the same diameter. The supporting shaft 10 supports the holding portion 7 to be held through both the members. The movable part 4 is processed along the spherical surface with the support shaft 10 penetrating and supporting the movable part 4 and the fixed part 7 without having a gap between the spherical parts of the movable part 4 and the fixed part 7. It is a structure that can move by changing the angle of the surface in contact with the object.
In the grip portion 2 ′, a polygonal bolt 14 that advances and retracts the support shaft 10 that penetrates the movable portion 4 and the fixed portion 7 is directly screwed to the rear end portion of the support shaft 10. Specifically, a female screw is cut at the rear end portion of the support shaft 10, and the polygonal bolt 14 is inserted into the female screw portion from the opposite surface of the concave spherical surface of the fixing member 7 by screwing. . A clamp block 11 is screwed to the tip of the support shaft 10 and engages with a recess 5d on the surface of the movable member 4 opposite to the convex spherical surface of the base member 5, and the clamp block 11 of the base member 5 engages. The holding member 6 having a surface in contact with the workpiece is fixed so as to cover the processed side.
Further, as shown in FIG. 8B, the rear end portion of the support shaft 10 screwed into the polygonal bolt 14 has a wall surface 8 ′ of the fixing member 8 on the surface opposite to the concave spherical surface of the fixing member 8. In between, it has the repulsion material 13. The support shaft 10 is always urged by the repulsive material 13 toward the surface in contact with the workpiece.

A mechanism in which the convex spherical surface of the movable part 4 of the grip portion 2 ′ is fixed by closely contacting the concave spherical surface of the fixed part 7 will be described.
When the polygonal bolt 14 on the opposite surface of the convex spherical surface of the fixed portion 7 is rotated clockwise with a spanner or the like, the support shaft 10 screwed into the polygonal bolt 14 has the convex spherical surface corresponding to the screw rotation along the axial direction. Move in the opposite direction. As a result, the clamp block 11 screwed to the tip of the support shaft 10 also moves to the opposite surface of the convex spherical surface, thereby pulling the base member 5 to be engaged in the same direction and the convex spherical surface of the base member 5. And the concave spherical surface 8c of the fixing member 8 are brought into close contact with each other and fixed.
On the other hand, when releasing the above-mentioned fixing, when the polygonal bolt 14 is turned counterclockwise, the direction of the surface of the repellent material 13 with which the rear end of the support shaft 10 abuts the workpiece is in contact. The support shaft 10 and the clamp block 11 are also moved in the direction of the surface in contact with the workpiece by the urging force, so that the close contact between the convex spherical surface 5c of the base member 5 and the concave spherical surface 8c of the fixing member 8 is released.

As described above, when the polygonal bolt 14 is arranged on the surface opposite to the concave spherical surface of the fixed member 8, the drive screw 3a of the linear drive screw portion 3 is attached to the movable gripping portion 2'a as shown in FIG. The fixing member 8 is installed on the lower part of the opposite surface of the concave spherical surface through a bearing 23 and the like, and the driving screw 3a is rotated to move the movable gripping part 2′a on the sliding part 22.
Further, in the grip portion 2 ′ in which the polygonal bolt 14 is screwed directly to the rear end portion of the support shaft 10, the angle of the support shaft 10 with respect to the surface in contact with the workpiece can be arbitrarily changed.

As shown in FIG. 1, FIG. 2 and FIG. 7, an abutment 19 is installed on the upper surface and side surface of the fixing portion 7 of the grip portion 2. When the workpiece 21 is gripped by the gripping device 1, the abutment 19 comes into contact with the back surface of the processed surface 21a or 21b of the workpiece and grips the workpiece on the basis of the processed surface. The size of the metal 19 is equal to or greater than the height of the movable part 4 protruding from the upper surface of the fixed part 7 when the angle of the surface gripped by the movable part 4 with respect to the fixed part 7 of the grip portion 2 is changed. Anything is acceptable.
Since the back surface of the workpiece is brought into contact with the abutment 19 and is gripped on the basis of the processing surface, it is possible to prevent the workpiece from being offset, and the processing surface of the workpiece is perpendicular to the tool of the machine tool. Can be kept in. Further, even when a load is applied to the work piece by the tool at the time of cutting by the machine tool, it is possible to perform the processing without causing the processing surface to be inclined.
When the workpiece is gripped, the convex spherical surface 5c of the base member 5 and the concave spherical surface 8c of the fixed member 8 are brought into close contact with each other, and the movable portion 4 and the fixed portion 7 are fixed, and the grip portion 2 is moved by the linear drive screw 3. If the workpiece is separated from the workpiece, the workpiece having the same shape can be subsequently gripped.
In the gripping device 1 of the present invention, the rib portion 21c of the workpiece is firmly fixed. By changing the angle of the gripping device 1 main body in this fixed state in the cutting process, it is possible to continuously process five surfaces other than the surface on which the rib portion 21c of the workpiece is provided. Moreover, circular processing of a workpiece is also possible by gripping and fixing with the gripping device 1 of the present invention.

  The workpiece gripping device of the present invention can firmly grip and fix the workpiece based on the processing surface, and can release the gripping of the workpiece with the gripping portion fixed. Any material can be processed, and even if the gripping part is released, no gap is formed between the concave and convex spherical surfaces of the gripping part and the machining chips do not enter between the spherical surfaces. Can be suitably used as a workpiece gripping device of a machine tool for cutting a workpiece.

It is a perspective view of the holding part of the workpiece holding apparatus which concerns on one Example of this invention. It is an assembly perspective view of a holding part. It is an assembly perspective view of a holding part. It is sectional drawing explaining the mechanism in which a movable site | part and a fixed site | part are fixed and unfixed. It is a figure which shows the outline of a workpiece holding apparatus. It is a perspective view explaining the workpiece gripped by the workpiece gripping device. It is a perspective view explaining embodiment of a work holding device. It is a top surface sectional view explaining another embodiment of a grasping part. It is side surface sectional drawing of the workpiece holding apparatus explaining another embodiment of a holding part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gripping device 2 Gripping part 3 Linear drive screw part 4 Movable part 5 Base member 6 Gripping member 7 Fixed part 8 Fixed member 9 Screw 10 Support shaft 11 Clamp block 12 Screw 13 Repulsive material 14 Polygon bolt 15 Washer 16 Auxiliary member 17 Slide Member 18 Block member 19 Gold 20 Spring 21 Workpiece 22 Sliding part 23 Bearing

Claims (7)

A workpiece gripping device in which at least one pair of gripping portions linearly moves in the direction of the other gripping portion and grips the workpiece,
The gripping portion includes a movable part having a convex spherical surface on the opposite surface of the surface in contact with the workpiece, a fixed part that holds the convex spherical surface of the movable part with a concave spherical surface having substantially the same diameter, and the movable part and the fixed part. A support shaft for supporting,
In the fixing portion, the support shaft penetrates from the opposite surface of the concave spherical surface,
The movable portion has the convex spherical surface and a base member having a concave spherical recess formed on the opposite surface of the convex spherical surface, a clamp block engaged with the concave, and the clamp block movable. A gripping member that covers and fixes the recess of the base member built in, and the engagement surface of the recess is a spherical surface that is concentric with the convex spherical surface and has a smaller diameter than the convex spherical surface,
The clamp shaft is fixed to the tip of the support shaft, the clamp block engages with the concave spherical recess of the movable part, and the support shaft penetrates the movable part and the fixed part so that both parts are Support,
By moving the support shaft forward and backward, the movable portion and the fixed spherical surface of the fixed portion are closely fixed, and the workpiece is gripped and fixed on the surface of the movable member that contacts the workpiece. Workpiece gripping device. The fixing portion includes a fixing member having the concave spherical surface and a polygonal bolt that is disposed on a surface opposite to the concave spherical surface of the fixing member and is inserted vertically from a side surface of the fixing member. A slide member that advances and retreats in the axial direction of the bolt and has a slope surface in the axial direction, and a slope surface that engages with the slope surface of the slide member. A block member that moves in a vertical direction with respect to the advancing and retracting direction, and the fixing member, the slide member, and the block member are connected by penetrating the support shaft,
The support shaft is advanced and retracted by rotating the polygonal bolt, and the slide member and the block member screwed into the polygonal bolt are interlocked, and the movable part and the movable part are moved forward and backward by engaging the movable part. 2. The workpiece gripping apparatus according to claim 1, wherein the opposing spherical surfaces of the fixed portion are fixed in close contact, and the workpiece is gripped and fixed on a surface of the movable member that is in contact with the workpiece. The fixed portion includes a fixing member having the concave spherical surface, and a polygonal bolt that is coupled by screwing in the axial direction of the support shaft from a rear end portion of the support shaft that passes through the movable portion and the fixed portion. And
The support shaft is advanced and retracted by turning the polygonal bolt, and the movable portion and the fixed spherical surface are closely fixed to each other by the advance and retreat of the clamp block engaged with the movable portion. 2. The workpiece gripping apparatus according to claim 1, wherein the workpiece is gripped and fixed on a surface in contact with the workpiece.   4. The first, second, or third aspect of the present invention, comprising a portion that contacts the reference portion of the work piece on the upper surface or the side surface of the fixed portion in order to hold the work surface of the work piece as a reference. Workpiece gripping device.   4. The workpiece gripping device according to claim 1, wherein a rotation angle of the clamp block is regulated by a gap with the clamp block formed in the recess of the base member.   The movable part is freely movable within a restricted range without generating a gap between the spherical surfaces of the movable part and the fixed part when the workpiece is released. The workpiece gripping device according to claim 2 or claim 3.   The movable portion has a plurality of springs on the lower surface thereof, and when the workpiece is released, the movable portion returns to the original position by a spring force. Item 4. A workpiece gripping apparatus according to Item 3.

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