JP7073616B2 - Chuck device and surface shape measuring machine - Google Patents

Description

The present invention relates to a chuck device for gripping a cylindrical workpiece and a roundness measuring device including the chuck device.

As a surface shape measuring machine for measuring the surface shape of a work, a roundness measuring machine for measuring the roundness of a cylindrical or cylindrical work is known (see Patent Document 1). In this roundness measuring machine, after the stylus of the detector is brought into contact with the surface of the work supported on the table, the table and the work are rotated about the rotation axis of the table. As a result, the outer peripheral surface of the work is traced along the circumferential direction by the stylus of the detector, and the roundness of the work can be obtained based on the displacement of the stylus.

In such a roundness measuring machine, a scroll chuck (chuck device) is provided on the table, and the work is gripped (held) by the scroll chuck. For example, the scroll chuck has three chuck claws arranged at equal intervals (120 ° intervals) on the same circumference centered on the central axis (rotation axis of the table), and each chuck claw has a central axis. It is provided with a chuck main body that holds the chuck so that it can be moved in the radial direction around the center, and a moving mechanism that is provided in the chuck main body and moves each chuck claw in the radial direction according to a rotation operation (see Patent Document 2). ..

This moving mechanism moves each chuck claw in the radial direction while maintaining a positional relationship arranged on the same circumference about the rotation axis. As a result, each chuck claw can be brought into contact with the outer peripheral surface or the inner peripheral surface (when the work is cylindrical) of various workpieces having different diameters. As a result, the work can be gripped at three points by the scroll chuck.

Japanese Unexamined Patent Publication No. 2005-147769 Japanese Unexamined Patent Publication No. 2011-45960

By the way, when the work is gripped at three points by the scroll chuck, if the rigidity of the work is high, the work will not be deformed by the contact with each chuck claw. However, when a cylindrical and thin workpiece is gripped at three points by a scroll chuck, the rigidity of the workpiece is low, so that the workpiece may be deformed by contact with each chuck claw.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a chuck device capable of gripping a cylindrical workpiece without deforming it, and a surface shape measuring machine provided with the chuck device.

The chuck device for achieving the object of the present invention is a chuck device for gripping a cylindrical workpiece, and is arranged radially around a central axis parallel to the vertical direction and has three rotation axes parallel to the vertical direction. , When the direction perpendicular to the vertical direction and the direction connecting the central axis and the three rotation axes is the radial direction, the three rotation axes are movably held along the radial direction of each rotation axis. An even number of chuck claws that are rotatably provided around the rotation axis for each rotation axis and the device body, and that grips the work when the device body moves each rotation axis toward the work. It is equipped with a chuck claw and.

According to this chuck device, the gripping force of each chuck claw can be reduced as compared with the case where the work is gripped at three points by three chuck claws.

In the chuck device according to another aspect of the present invention, the three rotation axes are kept in a positional relationship arranged on the same first circumference centered on the central axis.

In the chuck device according to another aspect of the present invention, the device main body keeps the three rotation axes in a positional relationship arranged at equal intervals on the first same circumference. As a result, the force from the chuck claw is prevented from being concentrated on a part of the area of the work, so that the deformation of the work is more reliably reduced.

In the chuck device according to another aspect of the present invention, when an even number of chuck claws for each rotation axis are set at a specific rotation position centered on the rotation axis, the second same with the center axis as the center. It is placed on the circumference. Thereby, each chuck claw can grip the outer peripheral surface or the inner peripheral surface of the cylindrical work.

In the chuck device according to another aspect of the present invention, each rotation axis is provided with a claw base rotatably provided around the rotation axis, and an even number of chuck claws are provided for each claw base.

In the chuck device according to another aspect of the present invention, a plurality of types of claw bases having different arrangements of an even number of chuck claws are selectively attached to the rotation shaft for each rotation axis, and among the plurality of types of claw bases. Satisfies the condition that an even number of chuck claws for each claw base that is a specific claw base and holds the work are arranged at equal intervals on the second same circumference centered on the central axis. A specific claw base is attached to each axis of rotation. As a result, the force from the chuck claw is prevented from being concentrated on a part of the area of the work, so that the deformation of the work is more reliably reduced.

In the chuck device according to another aspect of the present invention, a plurality of sub-rotating shafts rotatably provided around the rotating shaft and parallel to the vertical direction are provided for each rotating shaft, and a sub-rotating shaft is provided for each sub-rotating shaft. It is equipped with a claw base that is rotatably provided as a center. As a result, the force (grip force) applied to the work from each chuck claw can be more dispersed as compared with the case where the work is gripped at three points by three chuck claws, so that the grip force for each chuck claw can be more dispersed. Can be made smaller.

The surface shape measuring machine for achieving the object of the present invention measures the surface shape of the cylindrical work held by the above-mentioned chuck device.

The chuck device and surface shape measuring machine of the present invention can grip a cylindrical workpiece without deforming it.

It is a side view of a roundness measuring machine. It is a top view of the scroll chuck. It is a side view which looked at the scroll chuck of FIG. 2 from the direction A in the figure. It is explanatory drawing for demonstrating the movement of each moving body (each rotation axis) according to the rotation operation of a scroll plate. It is a top view of an arbitrary moving body and a claw base. It is explanatory drawing for demonstrating the gripping of a work by a scroll chuck. It is explanatory drawing for demonstrating the scroll chuck of the roundness measuring machine of 2nd Embodiment. It is explanatory drawing for demonstrating the scroll chuck of the roundness measuring machine of 3rd Embodiment. It is a side view of the roundness measuring machine of 4th Embodiment.

[Structure of Roundness Measuring Machine of First Embodiment]
FIG. 1 is a side view of a roundness measuring machine 10 corresponding to the surface shape measuring machine of the present invention. The X-axis direction, the Y-axis direction, and the Z-axis direction in the figure are orthogonal to each other. Further, the X-axis direction and the Y-axis direction are parallel to the horizontal direction, and the Z-axis direction is a direction parallel to the vertical direction.

As shown in FIG. 1, the roundness measuring machine 10 measures the roundness of a cylindrical work W extending in the Z-axis direction. The roundness measuring machine 10 includes a base 12, a table rotation mechanism 14, a table 16, a scroll chuck 18, a column 20, a carriage 22, an arm 24, and a detector 26.

The base 12 is a support base (base) that supports each part of the roundness measuring machine 10. Although not shown, the table rotation mechanism 14 includes an air bearing that rotatably holds the table 16 around the table rotation axis C1 parallel to the Z-axis direction, and a motor that rotates the table 16 around the table rotation axis C1. It is equipped with a rotation drive mechanism such as. As a result, the table rotation mechanism 14 rotates the table 16 around the table rotation axis C1.

The table 16 has a disk shape and is held on the air bearing of the table rotation mechanism 14 so that the center thereof coincides with the table rotation axis C1.

The scroll chuck 18 corresponds to the chuck device of the present invention. The scroll chuck 18 is provided on the table 16 and grips (holds) the work W in a posture parallel to the Z-axis direction. Further, the chuck central axis C2, which is the central axis of the scroll chuck 18, coincides with the above-mentioned table rotation axis C1. Therefore, when the table 16 is rotated by the table rotation mechanism 14, the scroll chuck 18 and the work W are rotated around the table rotation axis C1 (chuck center axis C2).

The column 20 is provided on the upper surface of the base 12 and on the side of the table 16 in the Y-axis direction, and has a shape extending in the Z-axis direction. A carriage 22 is attached to the column 20 so as to be movable in the Z-axis direction.

The carriage 22 is moved along the column 20 in the Z-axis direction by a carriage drive mechanism (not shown). The carriage 22 is provided with an arm 24.

The base end of the arm 24 is held on the surface side of the carriage 22 facing the work W. Further, a detector 26 is attached to the tip of the arm 24. The arm 24 has a structure in which the position of the detector 26 in the Y-axis direction and the posture of the detector 26 can be arbitrarily adjusted. The shape and structure of the arm 24 are not particularly limited as long as the position of the detector 26 in the Y-axis direction can be adjusted at least.

The detector 26 has a stylus 26a (also referred to as a stylus or a stylus) and a displacement detection unit such as a differential transformer (not shown), and the displacement of the stylus 26a that moves back and forth along the Y-axis direction. Is detected. Then, the detector 26 outputs a displacement detection signal (electrical signal) indicating the displacement of the stylus 26a to a data processing device (not shown).

The detector 26 is not limited to the contact type having the stylus 26a, and may be a non-contact type such as a laser probe.

When measuring the roundness of the work W, the carriage 22 and the arm 24 are driven to bring the stylus 26a of the detector 26 into contact with the outer peripheral surface of the work W. Next, the table rotation mechanism 14 rotates the table 16, the scroll chuck 18, and the work W around the table rotation axis C1, and the stylus 26a of the detector 26 causes the outer peripheral surface of the work W to rotate in the circumferential direction. Trace along. As a result, the displacement detection signal for one rotation of the work W is output from the detector 26 to a data processing device (not shown). This data processing device analyzes the detection signal input from the detector 26 by a known method, and calculates the roundness of the work W.

[Structure of Scroll Chuck of First Embodiment]
FIG. 2 is a top view of the scroll chuck 18. FIG. 3 is a side view of the scroll chuck 18 of FIG. 2 as viewed from the direction A in the figure. As shown in FIGS. 2 and 3, the scroll chuck 18 includes a chuck body 30, three moving bodies 32 (also referred to as jaws), three claw bases 34, six chuck claws 36, and three. The rotation shaft 50 and the like are provided.

The chuck main body 30 constitutes the apparatus main body of the present invention together with each moving body 32 described later, and includes a base portion 40, a scroll plate 42, and a cylindrical portion 44. In addition, each moving body 32 may be included in the chuck main body 30.

A cylindrical portion 46 (see FIG. 2) extending upward in the Z-axis direction is provided on the upper surface of the base portion 40. The center of the cylindrical portion 46 is the chuck central axis C2. In this embodiment, it is assumed that the chuck central axis C2 coincides with the table rotation axis C1 and the central axis of the work W (work central axis).

The scroll plate 42 is formed in a disk shape parallel to the XY plane. Further, an insertion hole (not shown) through which the columnar portion 46 is inserted is formed in the central portion of the scroll plate 42. The scroll plate 42 is rotatably supported on the upper surface side of the base portion 40 by the cylindrical portion 46 in a state where the cylindrical portion 46 is inserted into the insertion hole. Further, although not shown, a known spiral scroll groove is formed on the upper surface of the scroll plate 42 in the Z-axis direction with the chuck central axis C2 as the center (see, for example, Patent Document 2).

The cylindrical portion 44 has a shape extending in the Z-axis direction, and the cylindrical portion 46 is inserted therein. The cylindrical portion 44 is non-rotatably fixed to the cylindrical portion 46 on the upper surface side of the scroll plate 42. Further, the upper surface side of the cylindrical portion 44 in the Z-axis direction is covered with the ceiling plate 44a. The ceiling plate 44a is formed with three guide grooves 48 that are perpendicular to the chuck central axis C2 and extend radially from the chuck central axis C2. Specifically, each guide groove 48 is formed in the ceiling plate 44a at intervals of 120 ° in the direction around the chuck center axis C2.

The three moving bodies 32 are fitted into the guide grooves 48, respectively, and are supported by the guide grooves 48 so as to be movable along the radial direction of each of the moving bodies 32 (rotating shaft 50). The radial direction for each moving body 32 (rotating shaft 50) is a direction perpendicular to the chuck central axis C2 and a direction connecting the chuck central axis C2 and the rotating shaft 50 of each moving body 32, respectively.

The end portion of each moving body 32 on the lower side in the Z-axis direction is inserted into the cylindrical portion 44 from each guide groove 48 and is arranged on the scroll groove (not shown) of the scroll plate 42 described above. Further, a known rack tooth (see Patent Document 2) that meshes with the scroll groove of the scroll plate 42 is formed at the end portion of each moving body 32 on the lower side in the Z-axis direction.

Each moving body 32 is provided with a base holding portion 32a that constitutes an upper end portion in the Z-axis direction. Each base holding portion 32a is provided with a bearing 52 (see FIG. 3) that rotatably supports the rotating shaft 50 parallel to the Z-axis direction. Therefore, each rotating shaft 50 is radially arranged at intervals of 120 ° in the direction around the chuck center axis C2. The reference numeral C3 in the figure is the rotation center of each rotation axis 50.

Then, in each moving body 32, each rack tooth is described above in a state where each rotating shaft 50 is arranged at equal intervals on an arbitrary first same circumferential F1 centered on the chuck center axis C2. It meshes with the scroll groove (not shown) of the scroll plate 42.

FIG. 4 is an explanatory diagram for explaining the movement of each moving body 32 (each rotating shaft 50) according to the rotation operation of the scroll plate 42. As shown by reference numerals 4A and 4B in FIG. 4, when the scroll plate 42 is rotated, the rotation axis 50 of each moving body 32 is rotated by an arbitrary first identical circle due to a scroll groove and rack teeth (not shown). While maintaining the positional relationship arranged on the circumference F1, the rotary shaft 50 is moved forward and backward along the radial direction.

FIG. 5 is a top view of an arbitrary moving body 32 and a claw base 34. As shown in FIG. 5 and FIGS. 2 to 4 described above, a flat plate-shaped rotating plate 54 parallel to the XY plane is provided on the upper surface of the base holding portion 32a of each moving body 32 with respect to the rotating shaft 50. It is provided so that it can rotate freely. A claw base 34 is detachably fixed on the upper surface of the rotating plate 54 for each base holding portion 32a.

The three claw bases 34 are formed in a flat plate shape parallel to the XY plane. Two chuck claws 36 are provided on the upper surface of each claw base 34. As a result, for each rotating shaft 50, two chuck claws 36 are rotatably held with respect to the rotating shaft 50 via the claw base 34 and the rotating plate 54. Further, the upper surface of each claw base 34 serves as a support surface for supporting the work W.

Each chuck claw 36 has a pin shape extending in the Z-axis direction, and is brought into contact with the outer peripheral surface or the inner peripheral surface of the work W according to the rotation operation of the scroll plate 42. The shape of each chuck claw 36 is not limited to the pin shape, and any shape can be selected.

When the two chuck claws 36 on the claw base 34 are set at a specific rotation position centered on the rotation shaft 50, any second same circumferential F2 centered on the chuck center axis C2 ( (See FIG. 4). In other words, when the two chuck claws 36 are rotated around the rotation axis 50, the two chuck claws 36 are on the second same circumference F2 at any of the rotation positions (specific rotation positions). The positions of the two chuck claws 36 on the claw base 34 are adjusted so that they are arranged. As a result, all (6) chuck claws 36 can be arranged on the second same circumference F2.

Therefore, the six chuck claws 36 are moved back and forth integrally with the moving body 32, the rotating shaft 50, and the like by moving the two chuck claws 36 for each claw base 34 in accordance with the rotation operation of the scroll plate 42. Can be brought into contact with the outer peripheral surface or the inner peripheral surface of the. As a result, the work W can be gripped at 6 points by each chuck claw 36.

At this time, in the present embodiment, the six chuck claws 36 holding the work W are equidistant on the second same circumference F2, that is, at intervals of 60 ° around the chuck central axis C2. The position of each chuck claw 36 on each claw base 34 is adjusted so as to be arranged in. As a result, the work W can be gripped by the six chuck claws 36 arranged at equal intervals along the circumferential direction of the outer peripheral surface or the inner peripheral surface of the work W.

[Action of scroll chuck]
FIG. 6 is an explanatory diagram for explaining gripping of the work W by the scroll chuck 18 having the above configuration. In FIG. 6, a case where the work W is gripped by each chuck claw 36 from the outer peripheral surface side of the work W will be described as an example, but the work W will be gripped by each chuck claw 36 from the inner peripheral surface side of the work W. The same applies when letting them do.

As shown by reference numeral 6A in FIG. 6, the operator sets the work W to be measured at a predetermined position of the scroll chuck 18 of the roundness measuring machine 10. Next, when the scroll plate 42 is rotated in a predetermined rotation direction by the operator, the rotation shaft 50 of each moving body 32 keeps the positional relationship arranged on the first same circumference F1. It is moved toward the chuck central axis C2 (outer peripheral surface of the work W) along the radial direction of every 50.

Then, as shown by reference numeral 6B in FIG. 6, one of the two chuck claws 36 first contacts the outer peripheral surface of the work W for each rotation shaft 50 (claw base 34). At this time, the two chuck claws 36 are rotatably held by the rotating shaft 50 via the claw base 34 and the like. Therefore, when the rotation operation of the scroll plate 42 by the operator is continued with one of the two chuck claws 36 in contact with the outer peripheral surface of the work W, the two chucks are centered on the rotation shaft 50. The claw 36 is rotated. As a result, the other of the two chuck claws 36 is brought closer to the outer peripheral surface of the work W for each rotation shaft 50.

As shown by reference numeral 6C in FIG. 6, when the rotation operation of the scroll plate 42 by the operator is further continued, the work W is gripped (held at 6 points) by the six chuck claws 36. Then, the measurement of the roundness of the work W by the roundness measuring machine 10 is started. Since the roundness measurement is a known technique, a specific description thereof will be omitted here.

[Effect of this embodiment]
As described above, in the scroll chuck 18 of the present embodiment, the work W is gripped (six-point gripping) by the six chuck claws 36, so that the force (grip force) applied to the work W from each chuck claw 36 is applied. It is distributed to 6 points. As a result, in the present embodiment, the gripping force of each chuck claw 36 is smaller than in the case where the work W is gripped by the three chuck claws 36, so that the deformation of the work W is significantly reduced.

Further, in the present embodiment, the outer diameter of the work W is arranged so that the chuck claws 36 holding the work W are arranged at equal intervals (the above-mentioned 60 ° intervals) on the second same circumference F2. Alternatively, the position of each chuck claw 36 on each claw base 34 is adjusted according to the inner diameter. As a result, the force from the chuck claw 36 is prevented from being concentrated on a part of the region of the work W, so that the deformation of the work W is more reliably reduced.

[Second Embodiment]
FIG. 7 is an explanatory diagram for explaining the scroll chuck 18 of the roundness measuring machine 10 of the second embodiment. Since the second embodiment has basically the same configuration as the first embodiment, those having the same function or configuration as the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown by reference numeral 7A in FIG. 7, in the first embodiment, when the type (outer diameter or inner diameter) of the work W to be measured changes, each of the work W is gripped by the six chuck claws 36. The chuck claws 36 may not be arranged on the second same circumference F2 at equal intervals (60 ° intervals as described above).

Therefore, as shown by reference numeral 7B in FIG. 7, in the scroll chuck 18 of the second embodiment, a plurality of types of claw bases 34 having different arrangements of the two chuck claws 36 are selected for the rotating plate 54 for each rotating shaft 50. It is possible to attach it to the target. Thereby, a specific claw base 34A corresponding to the outer diameter or the inner diameter of the work W can be selected from a plurality of types of claw bases 34. The specific claw base 34A satisfies the condition that each chuck claw 36 holding the work W is arranged at equal intervals (the above-mentioned 60 ° interval) on the second same circumference F2.

Then, by attaching the specific claw bases 34A to the rotating plate 54 for each rotating shaft 50, even if the type of the work W to be measured changes, they are always arranged at equal intervals on the second same circumference F2. The work W is gripped by each of the chuck claws 36. As a result, even when the scroll chuck 18 selectively grips a plurality of types of work W, the deformation of each work W is surely reduced.

[Third Embodiment]
FIG. 8 is an explanatory diagram for explaining the scroll chuck 60 of the roundness measuring machine 10 of the third embodiment. In the third embodiment, the scroll chuck 60 has a rotating plate 62, two sub-rotating shafts 64, two sub-rotating plates 66, two claw bases 34, and four chucks for each rotating shaft 50. The configuration is basically the same as that of the first embodiment, except that the claw 36 is provided. Therefore, those having the same function or configuration as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 8, the three rotating plates 62 are formed in a flat plate shape parallel to the XY plane, and are rotatably attached to each of the three rotating shafts 50. Each rotating plate 62 is provided with two sub-rotating shafts 64 parallel to each other in the Z-axis direction.

When the two sub-rotating shafts 64 on the rotating plate 62 are set at a specific rotating position centered on the rotating shaft 50, the two sub-rotating shafts 64 are placed on any first co-circumferential F1A centered on the chuck central axis C2. Be placed. In other words, when two sub-rotation shafts 64 are rotated around the rotation shaft 50, the two sub-rotation shafts 64 become F1A on the same circumference at any rotation position (specific rotation position). The positions of the two sub-rotating shafts 64 on the rotating plate 62 are adjusted so as to be arranged. A sub-rotating plate 66 is rotatably attached to each of the sub-rotating shafts 64.

Each sub-rotating plate 66 is formed in a flat plate shape parallel to the XY plane. The above-mentioned claw base 34 having two chuck claws 36 is detachably fixed on the upper surface of each sub-rotating plate 66. As a result, the two chuck claws 36 on the claw base 34 are rotatably supported by the sub-rotating shaft 64, and are indirectly rotatably supported by the rotating shaft 50 via the rotating plate 62.

Further, when the two chuck claws 36 on the claw base 34 are rotated about the sub rotation shaft 64 in a state where the rotating plate 62 is set at a specific rotation position, one of the rotation positions (specification). The position is adjusted so that it is arranged at F2 on the second same circumference at (rotational position).

Therefore, two sub-rotating shafts 64 are set at specific rotation positions about the rotating shaft 50 for each rotating shaft 50, and two chuck claws 36 for each sub-rotating shaft 64 are centered on the sub-rotating shaft 64. When set to a specific rotation position, two chuck claws 36 on each claw base 34 are arranged on the second same circumference F2. Thereby, in the third embodiment, the work W can be gripped at 12 points by the twelve chuck claws 36 arranged on the second same circumference F2.

As described above, in the scroll chuck 60 of the third embodiment, since the work W is gripped (12-point grip) by the 12 chuck claws 36, the force (grip force) applied to the work W from each chuck claw 36 is 12. Distributed to points. As a result, the deformation of the work W is significantly reduced as in the first embodiment.

Further, in the third embodiment, the twelve chuck claws 36 holding the work W are equidistant at the second same circumference F2, that is, 30 ° in the axial direction around the chuck central axis C2. The position of each chuck claw 36 on each claw base 34 and the position of each sub-rotating shaft 64 on each rotating plate 62 are adjusted so as to be arranged at intervals. As a result, the work W can be gripped by the twelve chuck claws 36 arranged at equal intervals in the circumferential direction of the outer peripheral surface or the inner peripheral surface of the work W. As a result, similarly to the first embodiment, the force from the chuck claw 36 is prevented from being concentrated on a part of the region of the work W.

Two new sub-rotating shafts 64 are provided on each of the sub-rotating plates 66 shown in FIG. 8, and the sub-rotating plate 66 and the claw base 34 (two chuck claws 36) are provided for each new sub-rotating shaft 64. It may be provided. In this case, the work W can be gripped at 24 points by the 24 chuck claws 36. Similarly, the work W may be gripped at 48 points, 96 points, and so on. That is, an even number of chuck claws 36 may be directly or indirectly rotatably provided for each rotating shaft 50 with respect to the rotating shaft 50.

[Fourth Embodiment]
FIG. 9 is a side view of the roundness measuring machine 10A (corresponding to the surface shape measuring machine of the present invention) of the fourth embodiment. In the roundness measuring machine 10 of each of the above embodiments, the work central axis, which is the central axis of the work W gripped by the scroll chucks 18 and 60, coincides with the chuck central axis C2 (that is, the table rotation axis C1). Although it is assumed, the work central axis may actually be eccentric with respect to the chuck central axis C2.

Therefore, in the roundness measuring machine 10A of the fourth embodiment, the XY stage 70 is provided on the table 16, and the scroll chuck 18 (or the scroll chuck 60 is also possible) is provided on the XY stage 70. The roundness measuring machine 10A of the fourth embodiment has basically the same configuration as that of the first embodiment, except that the roundness measuring machine 10A includes the XY stage 70. Therefore, those having the same function or configuration as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

The XY stage 70 moves the scroll chuck 18 in the X-axis direction and the Y-axis direction, that is, moves the scroll chuck 18 two-dimensionally in the XY plane. As a result, based on the result of detecting the position of the work center axis of the work W chucked by the scroll chuck 18 by a known method, the XY stage 70 is driven to move the scroll chuck 18 in the XY plane, thereby moving the work. The work center axis of W can be aligned with the table rotation axis C1. As a result, the measurement accuracy of the roundness measurement of the work W by the roundness measuring machine 10A can be improved.

[others]
The shapes and structures of the chuck main body 30 and the moving body 32 of the scroll chucks 18 and 60 of each of the above embodiments are not limited to the shapes and structures described in the above drawings, and known shapes and structures are adopted. be able to.

In each of the above embodiments, the first F1 on the same circumference (F1A) and the second F2 on the same circumference are different, but they may be the same.

In each of the above embodiments, the rotation shafts 50 are arranged at equal intervals on the first F1 on the same circumference, and the chuck claws 36 holding the work W are equally spaced on the second F2 on the same circumference. However, these do not necessarily have to be arranged at equal intervals. Further, not all of the rotating shafts 50 need to be arranged on the first F1 on the same circumference. Further, when the work center axis of the work W is eccentric with respect to the chuck center axis C2, all of the chuck claws 36 holding the work W are not arranged on the second same circumference F2. It is also good. In this case, each chuck claw 36 holding the work W is arranged on the same circumference centered on the work center axis.

In the above embodiment, the scroll chucks 18 and 60 have been described as an example of the chuck device of the present invention, but the present invention can be applied to various three-chuck chucks such as an independent chuck.

In each of the above embodiments, the case where the scroll chucks 18 and 60 are provided in the roundness measuring machines 10 and 10A for measuring the roundness of the work W has been described, but the cylindricity, straightness and surface roughness of the work W have been described. The present invention can be applied to a surface shape measuring machine that measures various surface shapes of a work W such as undulations and waviness.

10,10A ... Roundness measuring machine,
18 ... Scroll chuck,
30 ... Chuck body,
32 ... moving body,
34, 34A ... Nail base,
36 ... Chuck claw,
50 ... rotation axis,
54 ... Rotating plate,
60 ... Scroll chuck,
62 ... Rotating plate,
64 ... Sub-rotation axis,
66 ... Sub rotating plate

Claims (10)

In a chuck device that grips a cylindrical workpiece,
The three rotation axes, which are arranged radially around the central axis parallel to the vertical direction and are parallel to the vertical direction,
When the direction perpendicular to the vertical direction and the direction connecting the central axis and the three rotation axes are the radial directions, the three rotation axes are set along the radial direction of each rotation axis. The device body that holds it movable and
The work is gripped when it is an even number of chuck claws rotatably provided around the rotation axis for each rotation axis and is moved toward the work for each rotation axis by the apparatus main body. With an even number of chuck claws
Equipped with
The apparatus main body keeps the three rotation axes in a positional relationship arranged on the same first circumference centered on the central axis.
When the even number of chuck claws for each rotation axis are set at a specific rotation position centered on the rotation axis, the chucks are arranged on the second same circumference centered on the center axis. Device. The chuck device according to claim 1 , wherein the device main body keeps the three rotation axes in a positional relationship arranged at equal intervals on the first same circumference. Each rotation axis is provided with a claw base rotatably provided around the rotation axis.
The chuck device according to claim 1 or 2, wherein the even number of chuck claws is provided for each of the claw bases. In a chuck device that grips a cylindrical workpiece,
The three rotation axes that are arranged radially around the central axis parallel to the vertical direction and are parallel to the vertical direction,
When the direction perpendicular to the vertical direction and the direction connecting the central axis and the three rotation axes are the radial directions, the three rotation axes are set along the radial direction of each rotation axis. The device body that holds it movable and
An even number of chuck claws rotatably provided around the rotation axis for each rotation axis, and the work is gripped when the device body moves the rotation axis toward the work. With an even number of chuck claws
For each rotation axis, a claw base rotatably provided around the rotation axis and
Equipped with
The even number of chuck claws is provided for each claw base.
A plurality of types of claw bases having different arrangements of the even number of chuck claws are selectively attached to the rotating shaft for each rotating shaft.
The even number of chuck claws for each claw base that is a specific claw base among a plurality of types of the claw bases and grips the work is a second identical circle centered on the central axis. A chuck device in which specific claw bases satisfying the conditions of being arranged at equal intervals on the circumference are attached to each rotation axis. For each of the rotation axes, a plurality of sub-rotation axes rotatably provided around the rotation axis and parallel to the vertical direction,
For each of the sub-rotating shafts, the claw base rotatably provided around the sub-rotating shaft and the claw base.
The chuck device according to claim 4 . In a chuck device that grips a cylindrical workpiece,
The three rotation axes that are arranged radially around the central axis parallel to the vertical direction and are parallel to the vertical direction,
When the direction perpendicular to the vertical direction and the direction connecting the central axis and the three rotation axes are the radial directions, the three rotation axes are set along the radial direction of each rotation axis. The device body that holds it movable and
An even number of chuck claws rotatably provided around the rotation axis for each rotation axis, and the work is gripped when the device body moves the rotation axis toward the work. With an even number of chuck claws
For each rotation axis, a claw base rotatably provided around the rotation axis and
Equipped with
The even number of chuck claws is provided for each claw base.
For each of the rotation axes, a plurality of sub-rotation axes rotatably provided around the rotation axis and parallel to the vertical direction,
For each of the sub-rotating shafts, the claw base rotatably provided around the sub-rotating shaft and the claw base.
A chuck device equipped with. The chuck device according to any one of claims 4 to 6, wherein the apparatus main body keeps the three rotation axes in a positional relationship arranged on the same first circumference centered on the central axis. The chuck device according to claim 7 , wherein the device main body keeps the three rotation axes in a positional relationship arranged at equal intervals on the first same circumference. A claim that when the even number of chuck claws for each rotation axis is set at a specific rotation position centered on the rotation axis, the chuck claws are arranged on the second same circumference centered on the center axis. Item 7. The chuck device according to Item 7 . A surface shape measuring machine for measuring the surface shape of a cylindrical work gripped by the chuck device according to any one of claims 1 to 9 .

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