JP4475393B2 - Work holder - Google Patents

Description

  The present invention relates to a work holder, and more particularly to a work holder that holds a workpiece by moving two engaging members closer to and away from each other.

  This type of work holder is already known as described in Patent Document 1 and Patent Document 2, for example. The work holder described in Patent Document 1 is configured to clamp and release a workpiece by using a cam to bring a pair of clamping claws closer to and away from each other. The work holder is held by a housing so as to be relatively rotatable, and is rotated by a main shaft of a machine tool. The work holder is relatively non-rotatable by the housing and is relatively movable in the axial direction, and is held concentrically with the rotating shaft. An operating shaft, a cylindrical driving cam fixed to the rotating shaft, a cylindrical driven cam provided on the operating shaft so as to face the driving cam, and a housing on a straight line perpendicular to the rotating axis of the rotating shaft And a pair of sandwiching claws provided so as to be able to approach and separate from each other, and a pair of links connecting the operating shaft and the pair of sandwiching claws. Corrugated cam surfaces having crests and troughs at a rotation angle interval of 90 degrees are formed on end surfaces of the driving cam and the driven cam, which are opposed to each other. And the driven cam are biased in the direction in which the cam surfaces mesh with each other. If the rotation shaft is rotated 90 degrees by the main shaft from the state where the crests and troughs of the cam surfaces of the driving cam and the driven cam are engaged with each other, the crests of the cam surfaces are brought into contact with each other, and the operating shaft is It is moved in a direction away from the rotating shaft, the pair of links are rotated, and the pair of clamping claws are separated from each other while being guided by the guide device, thereby releasing the workpiece. If the rotating shaft is further rotated 90 degrees in the same direction or in the opposite direction by the main shaft, the peak portion and the valley portion are brought into meshing state, and the pair of clamping claws are brought close to each other while being guided by the guide device. Hold it.

The work holder described in Patent Document 2 is configured to use a rack and a pinion to bring a pair of gripping members closer to and away from each other and grip and release the workpiece. This work holder is supported by a housing so as to be relatively rotatable and rotated by a main shaft, a pinion concentrically provided on the rotation shaft and provided with a non-rotatable and non-relatively movable axially, and a housing. A pair of racks that are held so as to be relatively movable in a direction perpendicularly intersecting the rotation axis of the rotation axis and meshed with the pinions, and a gripping member held in each of the racks are provided. The pair of racks are provided in parallel to each other, and if the rotation shaft is rotated by the main shaft, the pinion is rotated, the pair of racks are moved in opposite directions, and the pair of gripping members are separated from each other, Release the workpiece. If the rotation shaft is rotated in the opposite direction, the pair of racks are moved in the opposite direction to the above, and the pair of gripping members are brought close to each other to hold the workpiece.
JP-A-9-29574 JP 2003-181736 A

However, the work holder described in Patent Document 1 has a problem that it is not suitable for holding a plurality of types of workpieces having different sizes of held parts. Since the pair of clamping claws are moved toward and away from each other by linear movement to hold and release the workpiece, if a plurality of types of workpieces having different sizes of held portions are held by one workpiece holder, It is necessary to increase the approaching / separating distance of the nail. However, for this purpose, the guide device becomes large and the work holder becomes large. If you prepare multiple types of work holders according to the size of the held part, the work holder that holds the workpiece with the small held part can be configured small, but multiple types of work holders are required, The cost required to hold the workpiece increases.
The work holder described in Patent Document 2 has the same problem. In this work holder, the holding member is linearly moved by the movement of the rack. Therefore, if a plurality of types of workpieces having different sizes of the held parts are to be held, the rack is lengthened to increase the moving distance of the holding member. Therefore, it is inevitable that the work holder becomes large.
The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a work holder that can hold a plurality of types of workpieces having different sizes while suppressing an increase in size.

In order to solve the above-mentioned problem, a work holder according to the first invention of the present application is a work provided with a supported surface and two opposite engaged surfaces extending in a direction intersecting the supported surface. A work holder for holding a piece, comprising: (A) a main body member; (B) at least one support member having a support surface for supporting the supported surface; and (C) the two engaged surfaces. Two engaging members to be engaged; (D) two levers each held by the main body member, each holding the two engaging members, and at least one holding the support member; (E) a rotation shaft that is rotatably held by the main body member, and a motion conversion device that converts relative rotation of the rotation shaft with respect to the main body member into rotation of the two levers. By rotating the two engaging members, Look including a drive unit for moving in a direction approaching or away from the said support surface of the support member is parallel to the axis of the rotary shaft, the support surface is positioned on one plane, on one side of the one plane The main body member, the support member, the lever, and the driving device are disposed, and the rotating shaft is detachably attached to the main shaft of the processing machine, and the main body member is engaged with the non-rotating portion of the processing machine. Configured.

The work holder according to the second invention of the present application is a work holder for holding a work piece provided with an opening that opens on one surface, and (a) a main body member and (b) the work piece in contact with the one surface, respectively. Two support members having a support surface for supporting, and (c) two engagement members projecting from each of the support surfaces of the support members, entering into the opening and engaging the inner surface of the opening; (d) two levers each held by the main body member and holding each of the pair of support members, (e) a rotary shaft held by the main body member so as to be relatively rotatable, and a main body of the rotary shaft A motion conversion device that converts relative rotation with respect to the member into rotation of the two levers, and by rotating the two levers, the two engagement members are moved toward and away from each other. Drive device to move in the direction Look including the door, the supporting surface of the support member is parallel to the axis of the rotary shaft, the support surface is positioned on one plane, the body member on one side of the one plane, the support member, a lever and a driving device Is arranged, and the rotating shaft is detachably attached to the main shaft of the processing machine, and the main body member is configured to be engaged with a non-rotating portion of the processing machine .

In the work holder according to the first invention, the engagement member and the support member may be directly fixed to each other, or may be indirectly fixed via another member such as a lever. Further, they may be integrated with each other.
In the work holder according to the present invention, the two levers are rotated by the driving device, and the two engaging members are engaged with the engaged surface to hold the workpiece. Further, when the two engaging members engage with the workpiece, the supporting member can come into contact with the supported surface of the workpiece on the supporting surface, and the workpiece can be supported. If the two levers are rotated in the opposite direction by the driving device, the two engaging members are separated from the engaged surface to release the workpiece, and the support member is separated from the supported surface to be moved to the workpiece. Release the piece.
By setting at least one of the length of the lever, that is, the distance between the lever rotation axis and the engagement member, and the rotation angle of the lever, the maximum approach / separation distance between the two engagement members can be changed. Therefore, the lever has a length capable of holding a plurality of types of workpieces having different sizes of the held portion, and the rotation angle of the lever is set according to the distance between the two engaged surfaces. Thus, a plurality of types of workpieces can be held. When holding a workpiece having a large distance between the two engaged surfaces, the lever is rotated so that the engaging member is largely separated from the main body member. Can be rotated and closed to the main body member side, and a work holder capable of holding a plurality of types of workpieces having different sizes can be obtained while avoiding the work holder from becoming large.
Moreover, since this work holder is provided with the support surface and can support a workpiece by a surface, it can hold | maintain a workpiece stably. For example, when the supported surface is downward and the support surface is provided upward, the support member can support the workpiece from below, and when the workpiece is heavy, the engagement member is particularly heavy and has two centers of gravity. Even when a rotational torque around the straight line that deviates from the straight line connecting the two engaged parts held by the above-mentioned line is generated, it can be stably held. When the supported surface is an upward surface, the support surface is a downward surface, but rotation around the straight line connecting the two engaged portions of the workpiece is still prevented by the support surface, and the work holder is heavy. Even a workpiece can be stably held. The same applies to the case where the supported surface and the supporting surface are vertical or inclined. In order to hold the workpiece stably, it is desirable to provide two support members. For example, when the workpiece holder is provided in a processing machine and used to transfer the workpiece between devices, the workpiece is processed. It does not have to be held with high accuracy and accuracy, and there may be only one support member. Even if there is only one support surface, the workpiece can be supported widely by the surface, and sometimes only one is sufficient.
Furthermore, for example, the work holder can be configured compactly in a direction intersecting the rotation axis.
Further, if a main body member or the like is arranged on one side of the support surface, the space on the opposite side of the support surface from the main body member or the like is vacant, for example, a workpiece having a different shape, size, etc. It can be made to support on a support surface, without generating.

Also in the work holder according to the second invention, the engaging member and the supporting member may be directly fixed to each other, or may be indirectly fixed via another member such as a lever. Further, they may be integrated with each other.
In this work holder, the two engaging members engage with the inner side surface of the opening to hold the workpiece, and the two support surfaces support the workpiece. The two engaging members are engaged with the inner surface by applying a force in a direction away from each other, and the two supporting surfaces support the workpiece in the vicinity thereof, and the workpiece is stably held. The workpiece held by the work holder according to the second invention is a kind of workpiece held by the work holder according to the first invention, and can also be held by the work holder according to the first invention.
Also in the work holder according to the second invention, by setting the length of the lever and the rotation angle, it is possible to hold a plurality of types of workpieces having different opening sizes while suppressing an increase in size.
Moreover, the effect by arrange | positioning a main body member etc. on the one side of a support surface is acquired.

Aspects of the Invention

  In the following, the invention that is claimed to be claimable in the present application (hereinafter referred to as “claimable invention”. The claimable invention is at least the “present invention” to the invention described in the claims. Some aspects of the present invention, including subordinate concept inventions of the present invention, superordinate concepts of the present invention, or inventions of different concepts) will be illustrated and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is for the purpose of facilitating the understanding of the claimable invention, and is not intended to limit the combinations of the constituent elements constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

In each of the following paragraphs, the combination of paragraphs (1) , (5) and (7) corresponds to claim 1, and the combination of paragraphs (2) , (5) and (7) This corresponds to claim 2 . In addition, the matter described in paragraph (8) is added to claim 1 or 2 in claim 3 , and the matter described in claim (9) is added to claim 3 in claim 4 . Equivalent to.

(1) A work holder for holding a workpiece having a supported surface and two engaged surfaces extending in directions opposite to the supported surface and opposite to each other,
A body member;
At least one support member comprising a support surface for supporting the supported surface;
Two engaging members engaged with the two engaged surfaces;
Two levers respectively held by the body member, each holding the two engaging members, and at least one holding the support member;
A work holder including a driving device that moves the two engaging members in directions toward and away from each other by rotating the two levers.

(2) A work holder for holding a workpiece having an opening that opens on one surface,
A body member;
Two support members each having a support surface that contacts the one surface and supports the workpiece;
Two engaging members projecting from each of the supporting surfaces of the supporting members, entering into the opening and engaging the inner surface of the opening;
Two levers respectively held by the body member and holding each of the pair of support members;
A work holder including a drive device that moves the two support members in a direction in which the two engagement members approach and separate from each other by rotating the levers.
(3) The work holder according to (1) or (2), wherein the support member has a longitudinal shape, and an angle formed between the longitudinal direction of the support member and the longitudinal direction of the lever can be changed.
According to the work holder of this section, for example, the support position of the work piece by the support surface can be changed according to the shape, dimensions, etc. of the work piece, and the work piece can be held more stably. .

(4) A rotation shaft is held by the main body member so as to be relatively rotatable, and the driving device converts the rotation shaft and the relative rotation of the rotation shaft with respect to the main body member into rotation of the two levers. The work holder according to any one of (1) to (3), including a conversion device.
When the rotation shaft is rotated, the lever is rotated via the motion conversion device, and the engagement member holds and releases the workpiece.
The motion conversion device is, for example, a device including first and second screw members screwed together like the work holder described in (8), or a device including a cam and a cam follower. Various configurations can be employed. The latter motion converting device is a device that rotates the cam together with the rotating shaft and directly rotates the two levers by the motion of the cam follower provided by the cam.
(5) The work holder according to (4), wherein the rotating shaft is detachably attached to a main shaft of a processing machine, and the main body member is engaged with a non-rotating portion of the processing machine.
The work holder of this section is attached to a processing machine, and is used, for example, for attaching and detaching the work holder to be processed in the processing machine. The main body member is prevented from rotating by engagement with the non-rotating portion, and the rotation shaft is rotated by the main shaft, and the lever is rotated. The lever is rotated using the rotation of the spindle of the machine tool, and the workpiece can be easily held and released at a low cost.
(6) The work holder according to (4) or (5), wherein a support surface of the support member is parallel to an axis of the rotation shaft.
According to this section, for example, the work holder can be made compact in the direction intersecting the rotation axis.
(7) The work holder according to (6), wherein a support surface of the support member is positioned on one plane, and the main body member, the support member, a lever, and a driving device are arranged on one side of the plane.
If a main body member or the like is arranged on one side of the support surface, a space on the opposite side of the support surface from the main body member or the like is vacant, for example, a work piece having various shapes, dimensions, etc. may interfere with the main body member or the like And can be supported on the support surface.
In the case of the work holder of this section, when the support members are provided corresponding to the two engaging members, the support surfaces of the support members are respectively positioned on one plane. It is not essential that the support surfaces of the two support members are located on the same plane. For example, the support surfaces may be provided so as to be located in two different planes parallel to each other. The workpiece holder having the support surface is suitable for holding a workpiece having two supported surfaces, each of which has a stepped portion and is positioned in two different planes parallel to each other.

(8) The motion conversion device is
A first screw member that rotates with the rotating shaft;
A second screw member that is held by the main body member so as not to rotate relative to the main body and that can move relative to the axial direction, and is screwed with the first screw member; Is converted into rotation of the two levers. The work holder according to any one of (4) to (7).
The first screw member and the second screw member may be arranged coaxially with the rotation axis, or may be arranged on different axes. For example, the first and second screw members may be located in one plane including the axis of the rotation axis and disposed on an axis parallel to the axis of the rotation axis. In this case, for example, a rotation transmission device that transmits the rotation of the rotation shaft to the first screw member is provided between the first screw member and the rotation shaft so that the first screw member rotates together with the rotation shaft. .
In the work holder of this section, when the rotary shaft is rotated and the first screw member is rotated, the second screw member screwed to the first screw member is moved in the axial direction, and the two levers are moved. Are simultaneously rotated, and the engaging member holds and releases the workpiece. The first screw member is rotated in opposite directions when holding and releasing the workpiece, and the two levers are simultaneously rotated in the workpiece holding direction or the releasing direction.
According to this work holder, the engagement member is used to hold and release the work piece by utilizing the rotation of the rotation shaft. However, the rotation angle of the rotation shaft, that is, the rotation angle of the rotation shaft drive device that rotates the rotation shaft can Control can be easily performed. If the lead angle of the screw of the first and second screw members is reduced, the axial movement distance of the second screw member with respect to the same rotation angle of the first screw member can be shortened, and the actual rotation angle of the rotation shaft However, even if it is slightly larger than the angle required for holding the workpiece, the increase in the movement distance in the axial direction of the second screw member can be small. Therefore, even if the rotation angle of the rotating shaft for holding and releasing the workpiece is slightly larger than the angle suitable for holding, the workpiece is securely held without being damaged by applying excessive holding force. Therefore, the control of the rotation angle of the rotating shaft can be reduced, and the control becomes easy.
In addition, this work holder is suitable for holding a plurality of types of workpieces having different sizes of held parts. Increasing the rotation angle of the rotating shaft and the first screw member increases the rotation angle of the lever and increases the moving distance of the engaging member. , By setting a plurality of types of rotation angle ranges (angle ranges between the holding angle and the release angle) of the rotating shaft for releasing, it is easy to cope with the difference in the size of the held portion.

(9) The first screw member is held by the main body member so as to be relatively rotatable, and torque less than a set value is transmitted between the first screw member and the rotating shaft, but exceeds the set value. The work holder according to item (8), in which a torque limiter that does not transmit is provided.
When holding the workpiece, the two engaging members engage with the workpiece, and if the rotating shaft is further rotated from the held state and the first screw member is rotated, the engaging member holds the workpiece. There is a possibility that at least one of the workpiece and the engaging member may be damaged due to excessive force. On the other hand, if a torque limiter is provided, even if the rotating shaft is further rotated from the state in which the two engaging members are engaged and held by the workpiece, the rotational torque exceeding the set value is Not transmitted to the member. Therefore, for example, even if there is an error in the rotation angle control of the rotation shaft, the workpiece can be held without being damaged. Further, even if the engaging member is worn, the shortage of the approaching / separating distance between the two engaging members is automatically avoided, and the workpiece is reliably held.
Furthermore, the rotation angle control of the rotation shaft that is facilitated by configuring the motion conversion device including the first and second screw members is further facilitated. This is because even if the rotation angle of the rotation shaft is large, the torque limiter prevents transmission of torque exceeding the set value to the first screw member, thereby avoiding damage to the workpiece.
(10) The torque limiter is
A first limiter member that always rotates with the first screw member;
A second limiter member that always rotates with the rotating shaft;
One of the first limiter member and the second limiter member is provided with a plurality of first engaging portions provided on a circumference around one rotation axis, and the first limiter member and the second limiter member. A second engagement portion that is held on the other side and elastically engages with the first engagement portion, and the relative rotational torque between the first limiter member and the second limiter member is equal to or less than the set value. The work holder according to item (9), wherein the second engagement portion does not come off from the first engagement portion and comes off when it exceeds the set value.
The first screw member and the first limiter member, and the second screw member and the second limiter member may be arranged coaxially or on different axes.
The first limiter member and the second limiter member rotate relative to each other if the relative rotational torque exceeds the set value. However, since the plurality of first engaging portions are provided, the first and second limiter members are Regardless of the phase of the two limiter members, the first engagement portion and the second engagement portion are engaged with each other, and the torque limiter transmits torque below the set value but does not transmit torque exceeding the set value. Easy to return automatically. Therefore, for example, when holding the workpiece and releasing the workpiece, the operator does not engage the first and second engaging portions with each other so that the rotation of the rotating shaft is transmitted to the first screw member. Often done.
(11) The work holder according to item (10), wherein the first engagement portion and the second engagement portion face each other in the axial direction.
The first limiter member and the second limiter member are fitted so that one of the first limiter member and the second limiter member can be relatively rotated inside or outside of the other, and the first engagement portion and the second engagement portion are mutually connected in a direction perpendicular to the rotation axis. It is also possible to make them face each other. However, if the first engaging portion and the second engaging portion are opposed to each other in the axial direction, the torque limiter can be configured compactly.
(12) The work holder according to (10) or (11), wherein the first engagement portion is configured by a part of the corrugated uneven portion continuously formed along the one circumference.
The portion of the corrugated uneven portion that engages with the second engaging portion when the rotating shaft stops constitutes the first engaging portion, and the first engaging portion and the second engaging when the rotating shaft stops rotating Regardless of the relative phase with respect to the part, the first and second engaging parts are engaged, and a state of functioning as a torque limiter is obtained.
(13) The second engaging portion is
An accommodating recess provided in the other of the first limiter member and the second limiter member;
A ball that is held so that at least a part thereof protrudes from the front end opening of the housing recess;
The work holder according to any one of (10) to (12), further comprising an elastic member disposed in the housing recess and biasing the ball in a protruding direction.
In the state where the relative rotational torque is not more than the set value, the ball is kept engaged with one of the first and second limiter members and rotates both limiter members integrally. If the relative rotational torque exceeds the set value, the ball is retracted into the receiving recess against the urging force of the elastic member, allowing relative rotation of the first and second limiter members, and torque transmission is interrupted. .
The set value of the relative rotational torque is set to a magnitude corresponding to the elastic force of the elastic member. When a plurality of second engaging portions are provided, the number is selected such that the sum of the relative rotational torques corresponding to the elastic forces of the plurality of elastic members becomes a set value.
(14) The work holder according to any one of (10) to (13), wherein the first limiter member is provided coaxially with the first screw member.
The first limiter member may be provided on a different axis from the first screw member. In this case, for example, a rotation transmission device is provided between the first limiter member and the first screw member so that the rotation of the first limiter member is transmitted to the first screw member and rotates together. According to the work holder of this section, for example, the work holder can be configured compactly with respect to the direction intersecting the rotation axis of the rotation shaft.
(15) The work holder according to any one of (8) to (14), wherein the first screw member is disposed coaxially with the rotation shaft.
According to the work holder of this section, for example, the work holder can be configured compactly with respect to the direction intersecting the rotation axis of the rotation shaft.
(16) The movement conversion device is held by the main body member so as to be movable in a direction parallel to the rotation axis of the rotation shaft, and has a first engagement portion;
Each of the two levers includes a second engagement portion that engages with the first engagement portion, and the first engagement portion and the second engagement portion move the movable member. The work holder according to any one of items (4) to (15), which engages in a state that can be converted into rotation of each of the two levers.
One first engagement portion may be provided in common for the two second engagement portions, or one first engagement portion may be provided for each of the second engagement portions.
(17) The work holder according to any one of (1) to (16);
A tool spindle that rotates with a tool holding device that removably holds a processing tool at the tip; and
A workpiece attachment portion to which a workpiece to be machined by the machining tool is attached;
The tool spindle and the work mounting part are moved relative to each other so that the work holder held by the tool holding device of the tool spindle holds the work piece and is attached to the work mounting part, and instead of the work holder. And a relative movement device that causes the work tool held by the tool holding device to work the workpiece attached to the work attachment portion.
Using the tool spindle, the tool holding device, and the relative movement device, the work holder can be attached to the work attachment portion. As compared with the case where the workpiece holder is moved by a dedicated relative movement device and the workpiece is attached to the workpiece attachment portion, the processing machine can be configured easily and inexpensively. Further, if the work holder is accommodated in the processing tool accommodating device, a dedicated accommodating space is not required.
An automatic tool changer provided separately from the relative movement device performs an automatic change function for exchanging the work holder held in the tool holding device of the tool spindle with the machining tool or exchanging the work tool with the work holder. It is also possible to make it. However, it is also possible for the relative movement device to perform at least part of the automatic exchange function, which can further simplify the configuration.

Embodiments of the claimable invention will be described below in detail with reference to the drawings.
FIG. 1 schematically shows a processing machine which is an embodiment of the claimed invention. This processing machine is a machining center, and various workpieces including the workpiece 10 are processed. The workpiece 10 is provided with an opening 14 which opens on an end surface 12 which is one surface of the workpiece 10 and which is an outer surface perpendicular to the axis. In this embodiment, the inner side surface 16 of the opening 14 has a ring shape and is a surface orthogonal to the end surface 12. The workpiece 10 is, for example, a housing of an automobile transmission, and the inner side surface 16 forms a cylindrical surface.

  As schematically shown in FIG. 1, the present processing machine includes a workpiece holder 300, a tool spindle 302 (see FIG. 2) as a spindle, a workpiece holding jig 304, a tool spindle moving device 306 as a relative moving device, a tool, and the like. A storage device 307 and an automatic tool changer 308 are included. This processing machine is a so-called horizontal machine in which the rotation axis of the tool spindle 302 is provided horizontally, and the tool spindle moving device 306 has two directions orthogonal to each other in the horizontal plane (one in the X-axis direction and the other in the Y-axis). The tool spindle 302 is moved in the vertical direction (Z-axis direction). Therefore, the tool spindle moving device 306 includes an X-axis moving device 310, a Y-axis moving device 312 and a Z-axis moving device 314. The X-axis moving member 316 of the X-axis moving device 310 is moved in the X-axis direction by an X-axis driving device using a servo motor with an encoder (not shown) as a drive source, and the Y-axis moving member 318 of the Y-axis moving device 312 is moved. Is moved in the Y-axis direction on the X-axis moving member 316 by a Y-axis drive device using a servomotor with an encoder as a drive source. The Z-axis moving member 320 of the Z-axis moving device 314 is moved in the Z-axis direction on the Y-axis moving member 318 by a Z-axis driving device using a servomotor with an encoder as a driving source. A spindle housing 330 is provided on the Z-axis moving member 320 and constitutes a non-rotating portion of the processing machine. The tool spindle 302 is held rotatably around a horizontal axis parallel to the X-axis direction. Is rotated by a spindle rotation driving device 332 using a servomotor with an encoder as a driving source. The servo motor is an electric motor capable of accurately controlling the rotation angle, and a step motor may be used instead of the servo motor.

  In this embodiment, the work holding jig 304 is fixedly provided at a position adjacent to the X-axis moving device 310 in the X-axis direction, constitutes a work mounting portion, and holds and releases the workpiece 10. To do. A tool storage device 307 is mounted on the Y-axis moving member 318. In the tool storage device 307, a plurality of types of processing tools 342 and the work holder 300 are stored. The tool storage device 307 is a processing tool storage device that mainly stores the processing tool 342. An automatic tool changer 308 is mounted on the Z-axis moving member 320 together with the tool spindle 302. The automatic tool changer 308 is provided so as to be rotatable around a horizontal axis, and has a holding arm 348 as a holding member provided with holding parts 346 at both ends, an arm rotation driving device (not shown) for rotating the holding arm 348, and An arm moving device (not shown) that moves the holding arm 348 in a direction parallel to the rotation axis, and the like. By rotating and moving the holding arm 348, a machining tool is provided between the tool spindle 302 and the tool storage device 307. 342 and the work holder 300 are delivered. In the present processing machine, the workpiece 10 is carried in and out by a robot (not shown). The work holder 300 is attached to the tool spindle 302 and transfers the workpiece 10 to and from the robot and the workpiece holding jig 304.

The work holder 300 will be described.
As shown in FIG. 2, the work holder 300 includes a casing 400 as a main body member, an engaging device 402, two holding members 404, two levers 406, a driving device 408, and a torque limiter 410. The drive device 408 includes a rotation shaft 412 and a motion conversion device 414. The casing 400 holds the rotary shaft 412 via a plurality of bearings 416 so that the rotary shaft 412 can be relatively rotated around its axis and is not relatively movable in the axial direction. The rotating shaft 412 is provided with a shank portion 418 whose diameter decreases linearly toward the projecting end of the projecting portion from the casing 400. The shank portion 418 has a tapered shape provided at the tip of the tool spindle 302. A pull stud (not shown) that is fitted in the fitting hole 420 and protrudes from the shank portion 418 is pulled by the draw bar, and drawn into the tool spindle 302 and held. In addition, a plurality of engagement protrusions 426 provided at the tip of the tool spindle 302 are respectively fitted into a plurality of engagement recesses 428 provided at the base end portion of the shank portion 418 and engaged with each other. The rotation shaft 412 is prevented from rotating with respect to the tool spindle 302, and the rotation shaft 412 is rotatably attached to the tool spindle 302. The engagement protrusion 426 and the engagement recess 428 each constitute an engagement part or a rotation transmission part, and both constitute a rotation transmission device. The rotating shaft 412 can be detached from the tool spindle 302 by moving the rotating shaft 412 in a direction of coming out of the tool spindle 302 in a state in which the pull stud is not held by the draw bar.

  In this embodiment, the casing 400 includes a plurality of members assembled and fixed to each other, and includes a first member 440 and a second member 442. The first and second members 440 and 442 function as an integral casing 400 after assembly. The casing 400 is engaged with the main shaft housing 330 by the engaging device 402 to be prevented from rotating and allows the rotation shaft 412 to rotate. The engagement device 402 includes a casing 106 provided integrally with the casing 400, an engagement member 108 fitted in the casing 106 so as to be movable in a direction parallel to the rotation axis of the rotation shaft 412, and an engagement member And a compression coil spring 110 as an elastic member, which is a kind of a biasing device that biases 108 in the rearward direction from the casing 106, that is, in the same direction as the side from which the shank portion 418 of the casing 400 is projected. . The compression coil spring 110 is a kind of spring, and the limit of movement of the engaging member 108 by the bias of the spring 110 is that the flange portion 112 radially outward as an engaging portion provided in the engaging member 108 is It is prescribed | regulated by engaging with the shoulder surface 114 provided in the casing 100 as a stopper. In addition, the engaging member 108 is inserted into a pair of notches 118 that are provided in the casing 106 and constitute an engaging portion, by engaging a pin 116 as an engaging member penetrating in the diametrical direction. The rotation with respect to the casing 106 is prevented.

  The pin 116 extends from the casing 106 toward the rotating shaft 412, and when the work holder 300 is detached from the tool main shaft 302, the engagement member 108 is at a movement limit position due to the bias of the spring 110. The protruding end portion of 116 is fitted into the groove 120 provided at the proximal end portion of the shank portion 418, thereby preventing the rotation shaft 412 from rotating with respect to the casing 400. When the rotating shaft 412 is fitted to the tool spindle 302 and the engaging recess 428 is fitted to the engaging protrusion 426, the engaging protrusion 122 provided on the engaging member 108 is provided on the spindle housing 330. The engagement is inserted into the engagement recess 124 and the movement of the engagement member 108 is stopped. When the rotary shaft 412 is further fitted to the tool spindle 302 from this state, the casings 400 and 106 and the rotary shaft 412 move relative to the engaging member 108 in the axial direction, and the tool spindle 302 and the spindle housing 330 are moved. Approached, the pin 116 is pulled out of the groove 120. The engaging protrusion 426 is fitted into the engaging recess 428 before the pin 116 comes out of the groove 120. By extracting the pin 116, relative rotation between the casing 400 and the rotating shaft 412 is allowed, and the casing 400 holds the rotating shaft 412 so as to be relatively rotatable, and the casing 400 itself cannot be rotated relative to the spindle housing 330 by the engaging device 402. Once engaged, the rotating shaft 412 can rotate with the tool spindle 302. When the work holder 300 is removed from the tool spindle 302, the pins 116 are fitted into the grooves 120 before the engaging protrusions 426 are removed from the engaging recesses 428, and the phase between the rotating shaft 412 and the casing 400 is determined.

  The work holder 300 is attached to the tool spindle 302 in the same manner as the processing tool 342. The processing tool 342 includes a tapered shank portion, an engagement concave portion that is fitted to the engagement protrusion 426 of the tool spindle 302, and the like. The processing tool 342 is fitted to the tool spindle 302 so as not to be relatively rotatable, and is drawn by a draw bar. It is drawn in and held. In this embodiment, the engagement protrusion 426, the tapered fitting hole 420 into which the shank portion 418 is fitted, the draw bar, and the like constitute a tool holding device.

  The first member 440 constituting the casing 400 has a generally cylindrical shape, and the second member 442 has a shape in which a part of a disk having a diameter larger than the outer diameter of the first member 440 is cut out. The first member 440 is fixed concentrically while closing the opening. The casing 400 is formed with lever grooves 468 at two locations separated in the diameter direction. Each of these lever grooves 468 is formed in the first member 440, and is formed in the groove 470 that opens to the outer peripheral surface and the front end surface thereof, and in the second member 442, penetrates the second member 442 in the axial direction, and the front end surface thereof And a groove 480 that opens to the outer peripheral surface. The grooves 470 and 480 have the same width, and a lever groove 468 is formed across the first and second members 440 and 442.

  The lever 406 is fitted in each of the two lever grooves 468, and the two levers 406 are respectively rotated by the shaft 472 to the casing 400 and the rotation shaft 412 at one end fitted to the groove 470 side. It is an axis that intersects perpendicularly with the axis at right angles, is vertical, and is mounted so as to be rotatable around axes parallel to each other. The lever 406 protrudes from the front end surface of the casing 400 through the groove 480 and is guided to rotate mainly by the groove 480. The groove 480 forms a guide.

  A holding member 404 is attached to each of the free ends of the two levers 406 and the protruding ends from the casing 400. Each of these two holding members 404 includes a support plate 490 as a support member and a protruding member 492 as an engagement member in this embodiment. The support plate 490 has a longitudinal shape, and the projecting member 492 has a circular outer periphery with a cross-sectional shape, and as shown in FIGS. 3 and 4, mounting portions provided at the free ends of the two levers 406, respectively. They are fixed together at 494 by bolts 496 which are a kind of fixing means, and are directly fixed to each other. As shown in FIG. 3, the second member 442 is cut out at a notch surface 500 parallel to the plane of the outer periphery of the second member 442 that is separated in a direction perpendicular to the plane including the two lever grooves 468. As shown in FIGS. 3 and 4, the mounting portions 494 of the two levers 406 are respectively perpendicular to the longitudinal direction from the free end of the lever 406 and the rotation axis of the rotation shaft 412. It extends in a direction perpendicular to the three-dimensional intersection, and protrudes beyond one notch surface 500. A portion that is orthogonal to the plane including the two lever grooves 468 and that is separated from the notch surface 500 is also notched in a notch surface 501 that is parallel to the notch surface 500.

  At each of these protruding ends, the mounting surface 502 is provided in a state where the mounting surface 502 is positioned on a single horizontal plane parallel to the rotation axis of the rotating shaft 412, and the support plate 490 is placed on each mounting surface 502, respectively. The protruding member 492 is mounted in such a posture that its axis is perpendicular to the plate surface of the support plate 490 (vertical in this embodiment), and can be attached to and detached from the mounting portion 494 together by appropriate fixing means such as a bolt 496. It is fixed to. The support plate 490 is detachably fixed to the attachment portion 494 by another bolt 503 as a fixing means. In each of the two support plates 490, the surface opposite to the attachment portion 494 forms a support surface 504, and the outer peripheral surface of the protruding member 492 forms an engagement surface 506 perpendicular to the support surface 504. These two support surfaces 504 are parallel to the axis of the rotating shaft 412 and are positioned on a horizontal plane, and the casing 400, the support plate 490, the lever 406, and the driving device 408 are arranged on one side of the plane. Yes. With respect to the support plate 490, a portion other than the portion constituting the support surface 504 is disposed on one side of one plane where the support surface 504 is located. Further, as shown in FIG. 2, the free end portion of the lever 406 is bent in one plane with respect to the base end portion, and the support plate 490 is fixed in a posture inclined with respect to the base end portion of the lever 406. The two support plates 490 are fixed in such a manner that their tip ends (the free end side of the lever 406) approach each other.

  The two projecting members 492 are fixed in a state of projecting from the two support surfaces 504, and each projecting end of each projecting member 492 extends outward in the radial direction as shown in FIG. A flange portion 510 is provided, and an annular groove 512 is provided between the protruding member 492, the support plate 490, and the flange portion 510.

  In this embodiment, the motion conversion device 414 includes a male screw member 180 as a first screw member and a female screw member 182 as a second screw member, as shown in FIG. The male screw member 180 has a male screw portion 184 formed on the outer peripheral surface, and the lead angle of the male screw member 184 is reduced. The male screw member 180 is fitted to a portion in the casing 400 from a portion rotatably supported by the bearing 416 of the rotating shaft 412 so as to be rotatable about the axis of the rotating shaft 412 and not relatively movable in the axial direction. The male screw member 180 is held by the casing 400 so as to be relatively rotatable, and is arranged coaxially with the rotation shaft 412. The female screw member 182 has a female screw portion 186 formed on the inner peripheral surface, and is screwed into the male screw member 180. As shown in FIGS. 2 and 3, the female screw member 182 is provided with a groove 188 as an engaging portion that opens in the outer peripheral surface thereof and extends parallel to the axial direction, and is provided in the casing 400 in the radial direction. A projecting portion 190 as a joint portion is fitted, so that the female screw member 182 can move relative to the casing 400 in the axial direction but cannot rotate relative to the casing 400. Therefore, if the male screw member 180 is rotated, the female screw member 182 is moved in the axial direction and parallel to the rotation axis of the rotation shaft 412.

  As shown in FIG. 2, the two levers 406 are engaged with a female screw member 182 so as to be relatively rotatable. Each of these levers 406 is provided with a protrusion 200 extending from the portion rotatably connected to the casing 400 by a shaft 472 to the center side of the casing 400, and has an opening 520 provided in the bottom wall of the groove 470. As described above, each of the two grooves 202 provided in the female screw member 182 is rotatably fitted. As shown in FIG. 3, each of the two grooves 202 opens in the outer peripheral surface of the female screw member 182, and is in a direction that three-dimensionally intersects with the axis thereof at right angles and in a direction parallel to the rotation axis of the lever 406. The through holes are provided parallel to each other.

  As shown in FIG. 2, the protrusion 200 is orthogonal to a straight line passing through both the rotation axis of the lever 406 and the rotation axis of the rotation shaft 412 in the rotation plane of the lever 406 (horizontal plane in this embodiment). A part of the outer periphery of a cylinder centered on an axis parallel to the rotation axis of the lever 406 is cut out, and a pair of side surfaces separated in a direction parallel to the axis of the female screw member 182 of the groove 202 are provided. Each is contacted so as to be capable of relative rotation with sliding. Therefore, if the female screw member 182 is moved in the axial direction, the protrusion 200 is rotated around the axis of the shaft 472 by the movement of the groove 202, and the pair of levers 406 are simultaneously rotated. The movement of the female screw member 182 in the axial direction is converted into the rotation of the lever 406 by the groove 202 and the protrusion 200. In this embodiment, the groove 202 constitutes the first engaging portion, and the female screw member 182 The portion provided with the groove 202 constitutes a movable member, the protrusion 200 constitutes a second engaging portion, and constitutes the motion conversion device 414 together with the male screw member 180 and the female screw member 182.

  As shown in FIG. 2, the torque limiter 410 is provided between the male screw member 180 and the rotating shaft 412. The tip of the male screw member 180, that is, the end of the rotating shaft 412 opposite to the shank 418 side has a large diameter, and the first limiter member 220 is integrally provided. In this embodiment, the first limiter member 220 is provided coaxially with the male screw member 180 and always rotates together with the male screw member 180. On the annular end surface of the first limiter member 220, a corrugated uneven portion 222 is continuously formed along one circumference centered on the rotation axis of the male screw member 180, and constitutes a first engagement portion. ing. As shown in FIG. 5, the concavo-convex portion 222 has an arcuate cross-sectional shape and extends radially around the rotation axis of the male screw member 180. 226.

  As shown in FIG. 2, the second limiter member 230 is concentrically fixed to the rotating shaft 412 adjacent to the first limiter member 220 in the axial direction on the front side or the front side (the side opposite to the shank portion 418). Has been. The second limiter member 230 is fitted to the tip of the rotating shaft 412 and is fixed to the rotating shaft 412 by an appropriate fixing means such as a bolt, and is rotatably held by the casing 400 via a bearing 248. The rotation of the rotation shaft 412 is transmitted to the second limiter member 230 by a rotation transmission device or a relative rotation prevention device that includes the pin 250 and the recess 252 that respectively constitute the engaging portion. The front end of the rotating shaft 412 is rotatably supported by the casing 400 via the second limiter member 230, and the second limiter member 230 always rotates together with the rotating shaft 412 and constitutes the second engaging portion. A plurality of ball plungers 232 are held.

  The second limiter member 230 is provided with a plurality of receiving recesses 234 that are open on the surface of the first limiter member 220 facing the concave and convex portion 222 and extend in a direction parallel to the rotation axis of the rotation shaft 412 at equal angular intervals. In addition, each ball 236 is accommodated. The opening of the receiving recess 234 is slightly smaller than the diameter of the ball 236, and the ball 236 is held so that a part of the opening can protrude outward from the front end opening of the receiving recess 234. Further, the ball 236 is urged in a direction protruding from the housing recess 228 by a compression coil spring 238 as a spring which is a kind of elastic member disposed in the housing recess 234, and the projecting portion is It is made to fit in each of the recessed parts 224 of the uneven part 222. The concavo-convex portion 222 and the ball plunger 232 face each other in the axial direction, and the first and second limiter members 220 and 230 have a plurality of balls 236 of the plurality of ball plungers 232 engaged with the plurality of recesses 224, respectively. Can be engaged with each other. In each phase of the concavo-convex portion 222, a portion where the ball 236 is fitted constitutes a first engaging portion, and a portion of the concavo-convex portion 222 constitutes the first engaging portion.

  The relative rotational torque between the first limiter member 220 and the second limiter member 230 is a set value, that is, a torque necessary for retracting the ball 236 against the biasing force of the spring 238 in each of the plurality of ball plungers 232. In the state below the sum, the ball 236 is kept in the recessed portion 224, the first and second limiter members 220 and 230 are rotated together, and the rotation of the rotating shaft 412 is transmitted to the male screw member 180. The male screw member 180 rotates together with the rotating shaft 412. If the relative rotational torque exceeds the sum of the above torques, the plurality of balls 236 are simultaneously retracted into the receiving recess 234 against the urging force of the spring 238, get over the protrusion 226, and the second limiter member 230 becomes the first limiter member 230. The rotation of the rotation shaft 412 is not transmitted to the male screw member 180 by rotating with respect to the limiter member 220. The ball plunger 232 is provided in such a number that an appropriate set value is obtained and a set value (set torque) corresponding to the force with which the two holding members 404 can appropriately hold the workpiece 10 can be obtained.

  The processing machine is controlled by a control device 550 (see FIG. 1). The control device 270 is mainly composed of a computer, and controls the work holding jig 304, the tool spindle moving device 306, the tool storage device 307, the automatic tool changer 308, the spindle rotation driving device 332, etc. The holding and releasing of the workpiece 10 by controlling the machining of the workpiece 10 by the machining tool 342 and the like are controlled.

The holding of the workpiece 10 by the work holder 300 will be described.
The workpiece holder 300 receives an unprocessed workpiece 10 from a robot (not shown) and holds it on the workpiece holding jig 304. After the processing, the workpiece holder 300 receives the processed workpiece 10 from the workpiece holding jig 304 and passes it to the robot. . Therefore, the work holder 300 is attached to the tool spindle 302 prior to machining. The tool spindle 302 is moved to the tool storage device 307 by the tool spindle moving device 306, and the processing tool 342 held by the tool spindle 302 is returned to the tool storage device 307 by the automatic tool changer 308. The work holder 300 accommodated in 307 is held by the tool holding device of the tool spindle 302. At this time, as described above, the rotating shaft 412 of the work holder 300 is fitted into the fitting hole 420 of the tool spindle 302 in the shank portion 418, and relative rotation is achieved by fitting of the engaging protrusion 426 and the engaging recess 428. In addition to being blocked, the casing 400 is engaged with the main shaft housing 330 by the engaging device 402 so as not to rotate relative to the main shaft housing 330, so that the rotary shaft 412 can rotate together with the tool main shaft 302. The rotating shaft 412 rotates, but the casing 400 does not rotate, and the holding member 404, the lever 406, and the female screw member 182 do not rotate. In the state where the work holder 300 is housed in the tool housing device 307, the two levers 406 are closed, and as shown in FIG. 2, the longitudinal direction is substantially parallel to the rotation axis of the rotation shaft 412, and the whole is as a whole. It is stored in the groove 470 and the two holding members 404 are positioned at the storage position closest to each other. This storage position is also a non-holding position or a release position, and the work holder 300 is attached to the tool spindle 302 with the lever 406 and the like positioned at the storage position. Further, the present processing machine is a horizontal type, and the work holder 300 is held in such a posture that the rotation shaft 412 is horizontal and horizontal, and the support surfaces 504 of the two holding members 404 are held horizontally and upward. Each 492 protrudes upward from the support surface 504. Further, the protrusion 200 includes a rotation axis of the shaft 472, and is a base on the rear side (tool spindle 302 side) from the axis of the shaft 472 with respect to a vertical plane that is a plane perpendicular to the horizontal rotation plane of the lever 406. Located in position.

  Then, the tool spindle 302 is moved by the tool spindle moving device 306, and the workpiece holder 300 held by the tool spindle 302 receives the workpiece 10 from the robot. At this time, the two levers 406 are closed, and are accommodated in the lever groove 468 in a posture substantially parallel to the rotation axis of the rotation shaft 412 as shown in FIG. Yes. The workpiece 10 is held by the robot in a state where the opening 14 and the end face 12 face downward, like the workpiece 10 held by the workpiece holding jig 304 shown in FIG. Moved by the moving device 306, the two holding members 404 and the lever 406 are made to enter the lower side of the workpiece 10, and the protruding member 492 enters the opening 14 in a direction parallel to the axis of the protruding member 492, When the two levers 406 are opened, the lever 406 is moved to a position that engages with the inner side surface 16 and is set to a predetermined engagement position (also an operation position and a holding position).

  In this state, the tool spindle 302 is rotated in the workpiece holding direction by the spindle rotation driving device 332. Thereby, the rotating shaft 412 is rotated, and the rotation is transmitted to the male screw member 180 via the torque limiter 410, and the male screw member 180 is rotated. When holding the workpiece 10, the ball 236 is fitted in the concave portion 224 of the concave and convex portion 222, and the male screw member 180 is rotated by the rotation of the rotating shaft 412. As a result, the female screw member 182 is advanced, for example, as shown in FIG. 6, the two levers 406 are simultaneously rotated symmetrically to protrude from the casing 400, and the two holding members 404 are rotated by the rotating shaft 412. The two projecting members 492 are separated from each other and opened. A part of the part defining the opening 14 of the workpiece 10 is fitted into the groove 512, and the engaging surfaces 506 of the protruding members 492 of the two holding members 404 are linearly formed at two locations on the inner surface 16. Contact and hold the workpiece 10 together. The positions of the holding member 404 and the lever 406 when the two holding members 404 hold the workpiece 10 are referred to as holding positions (the holding positions in the approaching / separating direction of the two holding members 404).

  If the rotation angle of the rotating shaft 412 and the male screw member 180 is increased, the moving distance of the holding member 404 is increased, and the maximum approaching / separating distance between the two holding members 404 can be changed by setting the rotation angle of the lever 406. it can. A holding angle that is a rotation angle of the tool spindle 302 for holding the workpiece 10 on the two holding members 404 is set in advance according to the size of the workpiece 10. The release angle, which is the rotation angle of the tool spindle 302 for causing the two holding members 404 to release the workpiece 10, is an angle in a state where the lever 406 and the like are positioned at the storage position. The holding angle is set to such a size that the workpiece holder 300 can hold the workpiece 10 reliably, and the tool spindle 302 is further increased after the protruding members 492 of the two holding members 404 are engaged with the inner surface 16. Rotated. In this work holder 300, the male screw member 180 has a small lead angle, the moving distance of the female screw member 182 with respect to the unit rotation angle of the tool spindle 302, and hence the moving distance of the holding member 404 is short. Even when an error occurs in the rotation stop position, the stop position error of the holding member 404 may be small, the control accuracy of the rotation angle of the tool spindle 302 may be low, and the control can be easily performed.

  In addition, in the present embodiment, since the torque limiter 410 is provided, the workpiece 10 can be reliably held without being damaged, and the rotation angle can be controlled more easily. The rotational torque transmitted from the second limiter member 230 to the first limiter member 220 is not more than a set value until the protruding member 492 is engaged with the inner side surface 16, but after the engagement, the rotation shaft 412 further increases. It increases rapidly by being rotated. If the set value exceeds a preset value, the ball 236 is retracted into the housing recess 234 against the biasing force of the spring 238 and gets over the projection 226, so that the second limiter member 230 moves against the first limiter member 220. The rotation torque exceeding the set value is transmitted to the male screw member 180. Therefore, even if the rotation angle of the tool spindle 302 is set to be large, the two levers 406 are not forcibly rotated and the workpiece 10 is not damaged. The tool spindle 302 is stopped after being rotated by a predetermined angle, and the ball 236 is fitted into the recess 224. The concavo-convex portion 222 includes a plurality of concave portions 224 and convex portions 226, and the balls 236 are fitted into the concave portions 224 relative to each other regardless of the phase of the first and second limiter members 220 and 230 when the rotation of the tool spindle 302 is stopped. It is possible to return to the rotational torque transmission state.

  If the workpiece holder 300 holds the workpiece 10 in this way, the tool spindle 302 is moved by the tool spindle moving device 306, and the workpiece 10 is removed from the robot. Then, the tool spindle 302 is moved to the workpiece holding jig 304, and the workpiece 10 is attached to the workpiece holding jig 304 by the workpiece holder 300. The workpiece holder 300 holds the workpiece 10 from below, As shown in FIG. 4, the portion of the workpiece 10 that defines the opening 14 is in the groove 512 and the support surface 504 is located below the end surface 12. Therefore, the workpiece holder 300 can contact the vicinity of the opening of the end surface 12 on the two support surfaces 504 to support the workpiece 10 from below, and even if the workpiece 10 is heavy, it can be held without fear of dropping. Can be transported. In particular, the work holder 300 includes two support members 404 each having a support surface 504, and the support plate 490 has a longitudinal shape and is fixed to the lever 406 while being inclined. While being enlarged, it is made to contact the end surface 12 in the largest possible area, and can support the workpiece 10 stably. The end surface 12 is a supported surface, and the inner side surface 16 is a surface extending in a direction orthogonal to the supported surface. Of these, the portions where the two projecting members 492 are engaged are two oppositely directed two supported surfaces. An engagement surface is formed.

  The workpiece holder 300 is lowered after moving to the workpiece holding jig 304, and the workpiece 10 is attached. After the workpiece 10 is held by the workpiece holding jig 304, the tool spindle 302 is rotated by the same angle in the opposite direction to that when the workpiece 10 is held. As a result, the male screw member 180 is rotated in the reverse direction, the female screw member 182 is retracted, the two levers 406 are simultaneously rotated to the storage position, and the two projecting members 492 are brought closer to each other, thereby causing the inner surface. Move away from 16 and release workpiece 10. Then, the tool spindle 302 is lowered by the Z-axis moving device 314 and is moved in the X-axis and Y-axis directions by the X-axis moving device 310 and the Y-axis moving device 312, so that the work holder 300 is removed from the workpiece 10. At the same time, the tool spindle 302 is moved by the tool spindle moving device 306, and the work holder 300 is moved to the tool storage device 307. Next, the workpiece holder 300 is replaced with the machining tool 342, the machining tool 342 is held by the tool holding device instead of the workpiece holder 300, the tool spindle 302 is moved by the tool spindle moving device 306, and the workpiece holding jig 304 is moved. The workpiece 10 held by the machining tool 342 is machined by the machining tool 342. The processing tool 342 processes, for example, the outer surface of the workpiece 10 or the inner surface of a hole opened on the outer surface.

  After the machining is completed, the machining tool 342 is replaced with the work holder 300, the work holder 300 is held by the tool holding device, and the work holder 300 is attached to the tool spindle 302. Then, the work holder 300 is moved to the work holding jig 304 to hold the processed workpiece 10. This holding is performed in the same manner as when the workpiece holder 300 receives the workpiece 10 from the robot, and the workpiece 10 is removed from the workpiece holding jig 304 and transferred to the robot. Then, the unprocessed workpiece 10 is received from the robot and attached to the workpiece holding jig 304. Therefore, when the workpiece holder 300 releases the workpiece 10 delivered to the robot, the lever 406 and the like are not rotated to the storage position, and the engagement surface 506 is separated from the inner surface 16 to move the workpiece 10. Release and pivot to a release position sufficient for the protruding member 492 to exit the opening 14. The rotation angle of the tool spindle 302 in the reverse direction (work release direction) is set as such. When receiving the unprocessed workpiece 10 from the robot, the lever 406 and the like are moved from the release position to the holding position. However, the rotation angle is smaller than when the lever 406 and the like are returned to the storage position. 404 is opened and closed quickly, and the workpiece 10 is delivered quickly. After delivering the workpiece 10 to the robot, the lever 406 or the like may be returned to the storage position even when the workpiece 10 is received from the robot, or when the workpiece 10 is not received, the storage position is reached. Returned.

  In the work holder 300, for example, as shown in FIG. 7, as the rotation angle of the rotation shaft 412 is increased and the rotation angle of the lever 406 is increased, the moving distance of the holding member 404 in the radial direction is increased. The workpiece 10 having a large opening 14 can be held. The rotation angle of the rotary shaft 412 or the tool spindle 302 is set in advance according to the type of the workpiece 10. In the state where the workpiece 10 is not held, the two levers 406 are closed and stored in the lever groove 468 as shown in FIG. 2, and the work holder 300 is contracted to be in a compact state.

  When the workpiece 10 is attached to the workpiece holding jig 304, it is not essential to return the two holding members 404 and the lever 406 to the storage position in order to release the workpiece 10. For example, in a work mode in which the work holder 300 continuously holds a plurality of workpieces 10 on the workpiece holding jig 304, the workpiece holder 300 holds one workpiece 10 on the workpiece holding jig 304. It is not necessary to house the lever 406 and the like in the lever groove 468 every time. The holding member 404 and the lever 406 are moved from the holding position according to the size of the inner side surface 16 of the workpiece 10 and from the holding position to the inner side surface. What is necessary is just to rotate and move between the release positions which are enough to release | release the workpiece 10 away from 16. FIG. In this case, the tool spindle 302 or the rotating shaft 412 is rotated by an angle that moves the lever 406 and the like between the holding position and the release position that does not reach the storage position, and in both forward and reverse directions during holding and releasing. To the same angle. As the rotation angle of the rotation shaft 412 is increased, the moving distance of the holding member 404 is increased, the workpiece 10 having the larger inner surface 16 can be held, and the tool spindle 302 or the like for holding and releasing the workpiece 10 can be held. A plurality of types of rotation angle ranges (angle ranges between the holding angle and the release angle) of the rotation shaft 412 are set according to the size of the inner surface 16.

  The angle formed by the longitudinal support member and the longitudinal direction of the lever may be changeable. For example, in the above embodiment, the support plate 490 is fixed to the mounting portion 494 only by the bolt 496, the screwing of the bolt 496 is loosened, and the support plate 490 is rotated around the axis of the bolt 496 to Change the angle with the direction.

  Further, the work holder may hold the workpiece in a state where the support member is located above the engagement member and the support surface faces downward, and may be held by the tool holding device so as to hang the workpiece from above. In this case, the support member is positioned above the engagement member, the support surface of the support member is directed downward, and is engaged with the upward supported surface from the upper side to regulate the tilt and displacement of the workpiece and fall. Not to be transported.

  Further, the processing machine such as a machining center may be a so-called vertical processing machine in which a main shaft is rotated around a vertical axis. In this case, the work holder, for example, has a support surface that is vertical, and the two engagement members are moved toward and away from each other in the vertical plane to hold and release the workpiece. The support surface supports the workpiece from below. Although it does not do, the shift | offset | difference and inclination of a workpiece are controlled and holding | maintenance of the workpiece by two engagement members is assisted.

  In the above embodiment, the work holder 300 is configured such that the two engaging members are separated from each other to hold the workpiece 10 and are moved closer to each other to release the workpiece 10 or the like. The workpiece 10 may be held and may be separated from each other to release the workpiece 10. The held portion of the workpiece is held from the outside. In this case, the shape of the portion of the holding member that holds the workpiece is, for example, a shape corresponding to the shape of the held portion of the workpiece. For example, the holding member is provided with a concave portion having a triangular cross-sectional shape, and two surfaces of the concave portion that intersect each other are used as engaging surfaces and are held in contact with the outer side surface of the held portion as the held surface.

  Further, at least a part of the workpiece holding / release operation of the two engaging members and at least a part of the relative movement of the workpiece holder and the workpiece holding jig by the relative movement device are performed in parallel. Also good.

  The tool spindle may be rotated around an axis other than the vertical axis and the horizontal axis.

  Furthermore, the relative movement device may be a device that moves the workpiece attachment portion, or may be a device that moves both the tool spindle and the workpiece attachment portion.

  The claimable invention is also applicable to a processing machine other than a machining center, which is a processing machine provided with a work holder, a work holder of the processing machine, and a work holder that holds a workpiece in a device other than the processing machine. can do.

  Although several embodiments of the claimable invention have been described in detail above, these are merely examples, and the claimable invention includes the aspects described in the above [Aspect of the Invention]. The present invention can be implemented in various forms based on the knowledge of the trader.

It is a front view which shows the processing machine which is an Example of this invention. It is a top view (partial cross section) which shows the work holder of the said processing machine. It is a side view (partial cross section) which shows the said work holder. It is a front view (partial cross section) which shows the said work holder. It is an expanded view which shows the uneven | corrugated | grooved part and ball | bowl of the torque limiter of the said work holder. It is a figure explaining holding | maintenance of the workpiece by the said work holder. It is a figure explaining holding of another work piece by the above-mentioned work holder.

Explanation of symbols

  10: Workpiece 12: End face 14: Opening 16: Inner side surface 180: Male screw member 182: Female screw member 184: Male screw portion 186: Female screw portion 200: Protruding portion 202: Groove 220: First limiter member 222: Concavity and convexity 224: Concavity 226: Projection 230: Second limiter member 234: Housing recess 236: Ball 238: Compression coil spring 300: Work holder 302: Tool spindle 304: Work holding jig 306: Tool spindle moving device 307: Tool etc. storage device 308: Automatic tool changer 330: Spindle housing 342: Processing tool 404: Holding member 406: Lever 408: Drive device 410: Torque limiter 412: Rotating shaft 414: Motion converter 490: Support plate 492: Projection Material 504: bearing surface 506: engaging surface

Claims (4)

A work holder for holding a workpiece having a supported surface and two engaged surfaces extending in directions opposite to the supported surface and opposite to each other,
A body member;
At least one support member comprising a support surface for supporting the supported surface;
Two engaging members engaged with the two engaged surfaces;
Two levers respectively held by the body member, each holding the two engaging members, and at least one holding the support member;
A rotation shaft that is rotatably supported by the main body member; and a motion conversion device that converts relative rotation of the rotation shaft with respect to the main body member into rotation of the two levers, and rotates the two levers. it allows viewing contains a driving device for moving the two engaging members in a direction toward and away from each other, are parallel to the axis of the support surface is the rotational axis of the support member, the support surface is one plane The main body member, the support member, the lever, and the driving device are disposed on one side of the plane, and the rotary shaft is detachably attached to the main shaft of the processing machine. A work holder that is engaged with a non-rotating portion of the workpiece. A work holder for holding a workpiece having an opening that opens on one side,
A body member;
Two support members each having a support surface that contacts the one surface and supports the workpiece;
Two engaging members projecting from each of the supporting surfaces of the supporting members, entering into the opening and engaging the inner surface of the opening;
Two levers respectively held by the body member and holding each of the pair of support members;
A rotation shaft that is rotatably supported by the main body member; and a motion conversion device that converts relative rotation of the rotation shaft with respect to the main body member into rotation of the two levers, and rotates the two levers. A drive device for moving the two support members in a direction in which the two engagement members approach and separate from each other, and a support surface of the support member is parallel to an axis of the rotation shaft, and the support The surface is located on one plane, the main body member, the support member, the lever and the driving device are arranged on one side of the one plane, and the rotating shaft is detachably attached to the main shaft of the processing machine, A work holder characterized in that a main body member is engaged with a non-rotating portion of a processing machine . The motion conversion device is
A first screw member that rotates with the rotating shaft;
A second screw member that is held by the main body member so as not to rotate relative to the main body and that can move relative to the axial direction, and is screwed with the first screw member, the second screw member moving relative to the main body member in the axial direction; work holder according to claim 1 or 2, characterized in that for converting the rotation of said two levers. The first screw member is held by the main body member so as to be relatively rotatable, and torque less than a set value is transmitted between the first screw member and the rotary shaft, but torque exceeding the set value is not transmitted. The work holder according to claim 3 , wherein a torque limiter is provided.

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