Rotary shaft clamping device

Abstract

To provide a rotary shaft clamp device capable of securing a restriction force and positional accuracy with a simple structure.SOLUTION: A clamp device 40 is a rotary shaft clamp device that clamps a first member and a second member that can rotate relatively to each other around a predetermined central axial line. The clamp device 40 includes: a pair of contact surfaces 46 that are formed in an outer periphery of a disc 43 formed in a rotary shaft 41 being the first member, have a ring shape at a predetermined distance from the central axial line, and face each other at a regular interval; and a pressure contact member 44 supported by a support 42 being the second member and capable of pressure contacting the pair of contact surfaces 46. The pressure contact member 44 has a pair of surfaces 47 arranged in between the pair of contact surfaces 46, facing the contact surfaces 46 and being capable of advancing in a direction along the central axial line.SELECTED DRAWING: Figure 4

Description

Technical Field

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[0001] The present invention relates to a rotating shaft clamping device.

Background Art

[0002] In machine tools, for example, a rotation indexing device is used for adjusting the orientation and inclination of the spindle head of a multi-axis machine tool or for adjusting the angular position of a rotary table. In the rotation indexing device, a clamping device for restraining the rotating shaft at a predetermined angular position is installed together with a rotation driving device for rotating the rotating shaft. As the clamping device, an axis restraint type for restraining the rotating shaft or a disk type for restraining a disk mounted on the rotating shaft is used.

[0003] Examples of the axis restraint type include Patent Document 1 and Patent Document 2. In the axis restraint type rotating shaft clamping device, a diaphragm type displacement mechanism is pressed against the outer periphery of the rotating shaft and braked by friction. Examples of the disk type include Patent Document 3 and Patent Document 4. <0000s17>In the disk type rotating shaft clamping device, a disk mounted on the rotating shaft is fixed, and a diaphragm type displacement mechanism is pressed against the surface of the disk and braked by friction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0005] As mentioned earlier, the disc-type constraint allows for greater restraint force than the axial-constrained type because the distance of the restraint position from the center of rotation is greater. However, if the pressure on the disc is applied from only one side of the disc, a thrust load (in the direction of the rotational axis) is generated on the rotating shaft, which affects the positional accuracy of the rotary indexing device. Here, by applying pressure from both sides of the disc, the respective pressure forces can cancel each other out, thereby suppressing displacement in the direction of the rotational axis. However, if displacement mechanisms such as diaphragms are installed on both sides of the disc, there are impacts on the installation of the rotary indexing device, such as an increase in the number of parts and an increase in installation space.

[0006] The object of the present invention is to provide a rotating shaft clamping device that has a simple structure and can ensure restraining force and positional accuracy. [Means for solving the problem]

[0007] The rotary shaft clamping device of the present invention is a rotary shaft clamping device for clamping a first member and a second member that are rotatable relative to each other about a predetermined central axis, and comprises a pair of contact surfaces supported by the first member and formed in an annular shape at a predetermined distance from the central axis and facing each other at a constant interval, and a pressure contact member supported by the second member and capable of being pressed against the pair of contact surfaces, wherein the pressure contact member is positioned between the pair of contact surfaces and the pair of surfaces facing the contact surfaces are capable of advancing in a direction along the central axis.

[0008] In the rotating shaft clamping device of the present invention, the first member is a rotating shaft, the second member is a support that rotatably supports the rotating shaft, a disk is formed coaxially in the middle portion of the rotating shaft, a pair of contact surfaces are formed on the outer circumference of the disk and are opposite to each other in the direction of the central axis, and the pressure contact member may be supported by the support.

[0009] In this invention, the basic configuration is similar to that of existing disc-type clamping devices, and the rotational axis can be restrained from the support by the pressure contact member pressing against the contact surface, and the restraining force can be ensured by increasing the distance from the rotational axis to the pressure contact member. In this invention, since the pressure-contacting member is positioned between a pair of contact surfaces formed on the outer circumference of the disc, the structure of the clamping device can be simplified. Furthermore, since the pressure-contacting member presses against the inside of each of the pair of contact surfaces, and the contact force on each contact surface is equalized, no force (thrust force) is generated in the direction of the central axis due to the pressure-contacting on the rotating shaft, and the positional accuracy of the rotating mechanism can be ensured.

[0010] In the rotating shaft clamping device of the present invention, the first member is a support, the second member is a rotating shaft rotatably supported by the support, an annular contact member is formed on the inside of the support and coaxial with the rotating shaft, a pair of the contact surfaces are formed on the inside of the contact member and face each other in the direction of the central axis, and the pressure contact member may be supported by the rotating shaft.

[0011] In this invention, the arrangement of the contact member and contact surface is reversed compared to existing disc-type clamping devices. However, the contact member presses against the contact surface to restrain rotation relative to the support, and the restraining force can be ensured by increasing the distance from the rotation axis to the contact member. In this invention, since the pressure-contacting member is positioned between a pair of contact surfaces formed on the inside of an annular contact member, the structure of the clamping device can be simplified. Furthermore, since the pressure-contacting member presses against the inside of each of the pair of contact surfaces, and the contact force on each contact surface is equalized, no force (thrust force) is generated in the direction of the central axis due to the pressure-contacting on the rotating shaft, and the positional accuracy of the rotating mechanism can be ensured.

[0012] In the rotating shaft clamping device of the present invention, the first member is a rotating shaft, the second member is a support that rotatably supports the rotating shaft, a disk is formed coaxially in the middle portion of the rotating shaft, a pair of contact surfaces are formed on the outer edge of the disk and are opposite to the radial direction of the rotating shaft, and the pressure contact member may be supported by the support.

[0013] In this invention, the rotation axis can be restrained from the support by the pressure contact member pressing against the contact surface, and the restraining force can be ensured by increasing the distance from the rotation axis to the pressure contact member. In this invention, the pressure-contacting member is positioned between a pair of contact surfaces formed on the outer edge of the disc, and is located inside the outer circumference of the disc, thus simplifying and compacting the structure of the clamping device. Furthermore, since the pressure-contacting member presses against the inside of each of the pair of contact surfaces, and the contact force on each contact surface is equalized, no force (radial force) is generated on the rotating shaft in the direction intersecting the central axis due to the pressure-contacting, thus ensuring positional accuracy as a rotating mechanism.

[0014] In the rotating shaft clamping device of the present invention, the first member is a support, the second member is a rotating shaft rotatably supported by the support, an annular contact member is formed inside the support and coaxial with the rotating shaft, a pair of the contact surfaces are formed along the inner edge of the contact member and are opposite to the rotating shaft in the radial direction, and the pressure contact member may be supported by the rotating shaft.

[0015] In this invention, the contact member presses against the contact surface to restrain rotation relative to the support, and the restraining force can be ensured by increasing the distance from the axis of rotation to the contact member. In this invention, the pressure-contacting member is positioned between a pair of contact surfaces formed on the inner edge of the contact member, and can be positioned inside the outer circumference of the disk, thus simplifying the structure of the clamping device. Furthermore, since the pressure-contacting member presses against the inside of each of the pair of contact surfaces, and the contact force on each contact surface is equalized, no force (radial force) is generated on the rotating shaft in the direction intersecting the central axis due to the pressure-contacting, and positional accuracy as a rotating mechanism can be ensured.

[0016] In the rotating shaft clamping device of the present invention, it is preferable that the pressure contact member has a diaphragm that is flat and can bulge by the fluid pressure supplied therein. In the present invention, it is preferable that the diaphragm is formed on both surfaces of the flat pressure contact member. However, the diaphragm may be provided on only one side of the pressure contact member. When the diaphragm is provided on only one side of the pressure contact member, if it is supported slidably in the central axis direction with respect to the rotating shaft or the support of the pressure contact member, the thrust force can be surely eliminated. In such a present invention, by supplying a pressurized fluid to the pressure contact member to bulge the diaphragm, it is possible to make pressure contact with the contact surface. Further, by discharging the pressurized fluid from the pressure contact member, the diaphragm can be returned to its original shape and the pressure contact with the contact surface can be released. Such a diaphragm-type pressure contact member can simplify the structure and improve the maintainability.

[0017] In the present invention, as the pressure contact member, in addition to the diaphragm, a flat piston may be used. For example, a structure in which circular concave portions are formed on both surfaces of a flat base material and a circular plate-like piston is fitted therein can be used. Considering the sealing property around the piston, a resin balloon may be housed therein and hydraulic oil may be supplied therein. According to such a pressure contact member, it is easy to ensure the forward and backward stroke of the piston, and reliable clamping is possible even when the distance between the pressure contact member and the contact surface is relatively large. As the pressure contact member, a plate-like piezoelectric element may be used. For example, a structure in which plate-like piezoelectric elements are fixed to both surfaces of a flat base material can be used. According to such a pressure contact member, the piezoelectric element can be bulged by controlling the applied voltage to make pressure contact with the contact surface, and the structure can be further simplified compared with the case of using a fluid.

Advantages of the Invention

[0018] According to the present invention, it is possible to provide a rotating shaft clamping device having a simple structure and capable of ensuring the restraint force and the position accuracy.

Brief Description of the Drawings

[0019] [Figure 1] Front view showing the spindle head of the first embodiment of the present invention. [Figure 2] Side view showing the spindle head of the first embodiment. [Figure 3] Plan view showing the spindle head of the first embodiment. [Figure 4] Cross-sectional view showing the rotation shaft clamping device of the first embodiment. [Figure 5] Cross-sectional view showing the pressure contact member of the first embodiment. [Figure 6] Cross-sectional view showing another pressure contact member of the first embodiment. [Figure 7] Cross-sectional view showing another pressure contact member of the first embodiment. [Figure 8] Cross-sectional view showing another pressure contact member of the first embodiment. [Figure 9] Cross-sectional view showing the rotation shaft clamping device of the second embodiment of the present invention. [Figure 10] Cross-sectional view showing the rotation shaft clamping device of the third embodiment of the present invention. [Figure 11] Cross-sectional view showing the rotation shaft clamping device of the fourth embodiment of the present invention.

Modes for Carrying Out the Invention

[0020] 〔First Embodiment〕 In FIGS. 1 to 3, a 5-axis head 10 of a 五-axis machine tool is shown. The 5-axis head 10 rotates a cutting tool 12 mounted on the spindle 11 to machine a workpiece, and is mounted on a machine tool (not shown) and is movable in the three XYZ axial directions. Further, the 5-axis head 10 has a B-axis rotation indexing device 20 and a C-axis rotation indexing device 30, and the orientation of the spindle 11 can be rotated about two axes, the B-axis (around the Y-axis) and the C-axis (around the Z-axis).

[0021] The 5-axis head 10 has a spindle head 13, an arm body 14, and a head body 15. The head body 15 is formed in a rectangular box shape, and the upper surface side can be mounted on the tip of the ram 1 of the machine tool by a fastening mechanism (not shown). The arm body 14 is cut out from the lower side of a rectangular box along the X-axis, and its lower part is a pair of arms 141. A rotating shaft 142 is connected to the upper surface of the arm body 14. The rotating shaft 142 is rotatably supported by the head body 15.

[0022] The spindle head 13 is positioned between a pair of arms 141. The spindle head 13 has a cylindrical shape with its central axis aligned with the Y-axis, and rotating shafts 131 extending along the central axis of the spindle head 13 are connected to both end faces. Each of the pair of rotating shafts 131 extends into the interior of a pair of arms 141 and is rotatably supported by the arms 141. The spindle head 13 rotatably supports the main shaft 11 mentioned above and is equipped with a spindle motor (not shown) that rotates the main shaft 11.

[0023] A slip ring case 151 is installed on the upper surface of the head body 15. A slip ring rotating shaft 143 is connected to the upper end of the rotating shaft 142. The slip ring rotating shaft 143 is introduced into the slip ring case 151, and slip rings are formed inside the slip ring case 151. Electrical wiring and piping to the aforementioned spindle motor and the B-axis rotary indexing device 20 and C-axis rotary indexing device 30, which will be described later, are rotatably connected to the ram 1 side via the slip rings inside the slip ring case 151.

[0024] As a B-axis rotation indexing device 20, a pair of arms 141 are each equipped with a drive motor 21 and a clamping device 22. The pair of drive motors 21 rotate the rotation shaft 131, allowing the orientation of the main spindle 11 to be changed to any angular position on the B-axis (see Figure 2). The pair of clamping devices 22 can restrain and clamp the rotation shaft 131 while the spindle head 13 is at any angular position on the B-axis relative to the arm body 14.

[0025] As a C-axis rotation indexing device 30, the head body 15 is equipped with a drive motor 31 and a clamping device 32. The drive motor 31 rotates the rotation shaft 142, allowing the orientation of the arm body 14 to be changed to any angular position on the C axis (see Figure 3). The clamping device 32 can restrain and clamp the rotation shaft 142 when the arm body 14 is at any angular position on the C axis relative to the head body 15.

[0026] In this embodiment, the clamping device 40 shown in Figure 4 is used as the clamping device 22 of the B-axis rotary indexing device 20 and the clamping device 32 of the C-axis rotary indexing device 30, respectively. In the clamping device 40 shown in Figure 4, the rotating shaft 41 is either the rotating shaft 131 in the clamping device 22 or the rotating shaft 142 in the clamping device 32. The support body 42 is either the arm body 14 in the clamping device 22 or the head body 15 in the clamping device 32.

[0027] The clamping device 40 comprises a disk 43 fixed to the middle part of the rotating shaft 41 (first member) and a pressure contact member 44 supported by a support 42 (second member). Annular contact members 45 are fixed to both sides of the outer circumference of the disk 43. The pair of contact members 45 are arranged opposite each other at a predetermined interval in the direction of the central axis A of the rotation shaft 41, and a pair of contact surfaces 46 are formed on each of the opposing surfaces. The pair of contact surfaces 46 are formed in an annular shape at a predetermined distance from the central axis A of the rotation shaft 41 and are opposed to each other at a constant interval. The contact member 44 is formed to be annular and flattened in the direction of the central axis, and is arranged concentrically around the entire circumference of the outer surface of the disk 43 (see Figure 3). A portion of the contact member 44 is positioned between a pair of contact surfaces 46, and a pair of front and back surfaces 47 facing the contact surfaces 46 can advance in the direction along the central axis A of the rotation axis 41.

[0028] In Figure 5, the pressure-welding member 44 can be a member that is flat overall, has a cavity 441 inside, and has diaphragms 442 on both sides 47. With such a pressure-welding member 44, by supplying pressurized fluid to the internal cavity 441 from the outside, the diaphragm 442 expands due to the fluid pressure, and the surface 47 can be pressed against the contact surface 46.

[0029] If the pressure contact members 44 are positioned at equal distances from the pair of contact surfaces 46, the supply of pressurized fluid will cause the diaphragms 442 on both sides to expand evenly, and the surfaces 47 on both sides will simultaneously contact the pair of contact surfaces 46, resulting in even pressure contact. As a result, the frictional force between the two surfaces 47 and the contact surface 46 restrains the contact member 45 with the pressure contact member 44, clamping the rotation axis 41 to the support 42. At this time, the pressure contact forces applied from the two surfaces 47 to the opposing contact surface 46 cancel each other out because they are in opposite directions on each side, and no displacement of the rotation axis 41 relative to the support 42 occurs.

[0030] In contrast, if the pressure-welding member 44 is biased towards one of the pair of contact surfaces 46, the pressure-welding of each side's surface 47 to the contact surface 46 will be performed sequentially. In other words, as the diaphragm 442 expands due to the supply of pressurized fluid, the surface 47 on the off-center side first comes into contact with the opposing contact surface 46, suppressing the expansion of the diaphragm 442. The diaphragm 442 on the opposite side from the off-center side continues to expand. In this state, when the surface 47 and the contact surface 46 are pressed together only on the biased side, the pressing force on that side acts on the rotating shaft 41. However, at this stage, the pressing force can be borne by the rotational support structure of the rotating shaft 41 provided by the support 42, and does not cause displacement of the rotating shaft 41.

[0031] The subsequent supply of pressurized fluid causes the surface 47 on the opposite side from the biased side to come into contact with the opposing contact surface 46, suppressing the bulging of the diaphragm 442. Then, by further pressurizing the fluid, the surfaces 47 on each side are pressed against the opposing contact surface 46 via the diaphragms 442 on both sides. As a result, similar to the case of even arrangement described above, the frictional force between the two surfaces 47 and the contact surface 46 restrains the contact member 45 with the pressure member 44, and clamps the rotation axis 41 to the support 42. At this time, the pressure forces applied from the two surfaces 47 to the opposing contact surface 46 cancel each other out because they are in opposite directions on each side, and no displacement of the rotation axis 41 relative to the support 42 occurs.

[0032] Therefore, the clamping device 40 of this embodiment can have a basic configuration similar to that of existing disc-type clamping devices, and the rotating shaft 41 can be restrained from the support 42 by the pressure contact member 44 pressing against the contact surface 46, and the restraining force can be ensured by increasing the distance from the rotating shaft 41 to the pressure contact member 44 by the outer diameter of the disc 43. Furthermore, in this embodiment, since the pressure contact member 44 is positioned between a pair of contact surfaces 46 formed on the outer circumference of the disk 43, the structure of the clamping device 40 can be simplified. Moreover, since the pressure contact member 44 presses against the inside of each of the pair of contact surfaces 46, and the contact force on each of the contact surfaces 46 is equalized, no force (thrust force) is generated in the direction of the central axis A due to the pressure contact on the rotating shaft 41, and the positional accuracy of the rotating mechanism, the B-axis rotation indexing device 20 and the C-axis rotation indexing device 30, can be ensured.

[0033] Furthermore, since the two B-axis rotary indexing devices 20 are installed at both ends of the arm body 14, maintenance and inspection can be easily performed by opening the end covers of the arm body 14.

[0034] [ Pressure-welded member Other embodiments] In this embodiment, instead of the pressure-welding member 44 in Figure 5, the pressure-welding members 44A to 44C shown in Figures 6 to 8 can also be used. In Figure 6, the contact member 44A is flat overall and has a cavity 441 inside. The cavity 441 is off-center to one side of the contact member 44A, and only one of the two surfaces 47 is a diaphragm 442. The contact member 44A is fitted into a recess 421 formed in the support 42, and a pin 422 extending in the axial direction of the rotating shaft 41 passes through it, restricting its movement in the rotational direction of the rotating shaft 41 while allowing it to be displaced in the axial direction of the rotating shaft 41.

[0035] In such a pressure-welded member 44A, by supplying pressurized fluid to the internal cavity 441 from the outside, the diaphragm 442 expands due to the fluid pressure, and one surface 47 presses against the opposing contact surface 46. By supplying further pressurized fluid, the diaphragm 442 expands and the pressure-welded member 44A is displaced, and the opposite surface 47 also presses against the opposing contact surface 46. As a result, both surfaces 47 press against the pair of contact surfaces 46, and sufficient restraining force can be ensured by supplying further pressurized fluid. On the other hand, no force (thrust force) is generated in the direction of the central axis A in the rotating shaft 41 due to the pressure-welding.

[0036] In the clamping device 40 shown in Figure 6, a contact member 45 is positioned on one side of the pressure-contacting member 44A, while a contact portion 43A, which is an extension of a part of the disc 43, is positioned on the opposite side. In this structure, the pressure-contacting member 44A can be introduced between the pair of contact surfaces 46 by removing one of the contact members 45 from the disc 43. This is also true for the clamping devices 40 shown in Figure 5, and later in Figures 7 and 8.

[0037] In Figure 7, the pressure-welding member 44B is flat overall and has a cavity 441 inside, with both sides of the surface 47 formed by flat pistons 443. In such a pressure-welding member 44B, by supplying pressurized fluid to the internal cavity 441 from the outside, the pistons 443 advance due to the fluid pressure, and the surface 47 can be pressed against the contact surface 46.

[0038] In Figure 8, the pressure contact member 44C is formed in a flat plate shape overall, and both sides of the surface 47 are formed of flat piezoelectric elements 444. In such a pressure contact member 44C, applying a voltage to the piezoelectric elements 444 causes the piezoelectric elements 444 to bulge, and the surface 47 can be pressed against the contact surface 46.

[0039] [Second Embodiment] This embodiment is a 5-axis head 10 for a 5-axis machine tool similar to the first embodiment described above, but with a different configuration of the clamping device 40. The configuration that differs from the first embodiment will be described below. Figure 9 shows the clamping device 40A of this embodiment. In the clamping device 40 of the first embodiment described above, a pair of contact surfaces 46 were formed on a disk 43 fixed to a rotating shaft 41, and a pressure contact member 44 was supported by a support 42. In contrast, in the clamping device 40A of this embodiment, the arrangement of the contact member 44 and the pair of contact surfaces 46 on the rotating shaft 41 and the support 42 is reversed.

[0040] In Figure 9, the support 42 has an annular groove formed on its cylindrical inner surface, and the opposing inner surfaces of the groove form a pair of contact surfaces 46. The pair of contact surfaces 46 are formed in an annular shape at a predetermined distance from the central axis A of the rotation shaft 41 and are opposed to each other at a predetermined interval in the direction of the central axis A. One side of the groove forming the pair of contact surfaces 46 is a contact portion 42A that is continuous with the support 42, and the other side is an annular contact member 45A that is detachably fixed to the support 42. The pressure contact member 44 is fixed radially outward to the outer circumference of the disk 43 and extends between each pair of contact surfaces 46. The pressure contact member 44 can be introduced into the groove with the contact member 45A removed from the support 42. The contact member 44 has the configuration shown in Figure 5 or the configuration shown in Figures 6 to 8 (contact members 44A to 44C), and a pair of front and back surfaces 47 facing the contact surface 46 can advance in a direction along the central axis A of the rotation shaft 41.

[0041] In this embodiment as well, by advancing the surfaces 47 on both sides of the pressure contact member 44 and pressing them against the pair of contact surfaces 46, the rotation axis 41 can be restrained without displacing the support 42, resulting in a simple structure while ensuring restraining force and positional accuracy.

[0042] [Third Embodiment] This embodiment is a 5-axis head 10 for a 5-axis machine tool similar to the first embodiment described above, but with a different configuration of the clamping device 40. The configuration that differs from the first embodiment will be described below. Figure 10 shows the clamping device 40B of this embodiment. In the clamping device 40 of the first embodiment described above, the pair of contact surfaces 46 on the outer circumference of the disk 43 fixed to the rotating shaft 41, and the surface 47 of the pressure contact member 44 supported by the support 42, were each arranged along the radial direction of the rotating shaft 41. In contrast, in the clamping device 40B of this embodiment, the surface 47 and the pair of contact surfaces 46 of the pressure contact member 44 are arranged in a direction intersecting the radial direction of the rotation axis 41, that is, along the circumferential direction of the rotation axis 41.

[0043] In Figure 10, a pair of contact members 45B are fixed to one side near the outer circumference of the disk 43. The pair of contact members 45B are arranged coaxially with respect to the central axis A of the rotation shaft 41, and a pair of contact surfaces 46 are formed on their opposing surfaces. The pair of contact surfaces 46 are formed in an annular shape at a predetermined distance from the central axis A of the rotation shaft 41 and are facing each other at a constant interval. The pressure contact member 44 is supported by an inner flange 423 that protrudes from the inside of the support 42, and extends in the direction of the central axis A of the rotation shaft 41, reaching between the pair of contact surfaces 46. The contact member 44 has the configuration shown in Figure 5 or the configuration shown in Figures 6 to 8 (contact members 44A to 44C), and a pair of front and back surfaces 47 facing the contact surface 46 are aligned with the central axis A of the rotation shaft 41. orthogonal diameters It is possible to advance in that direction.

[0044] In this embodiment as well, by advancing the surfaces 47 on both sides of the pressure contact member 44 and pressing them against the pair of contact surfaces 46, the rotation axis 41 can be restrained without displacing the support 42, resulting in a simple structure while ensuring restraining force and positional accuracy.

[0045] [Fourth Embodiment] This embodiment is a 5-axis head 10 for a 5-axis machine tool similar to the first embodiment described above, but with a different configuration of the clamping device 40. The configuration that differs from the first embodiment will be described below. Figure 11 shows the clamping device 40C of this embodiment. In the clamping device 40 of the first embodiment described above, the pair of contact surfaces 46 on the outer circumference of the disk 43 fixed to the rotating shaft 41, and the surface 47 of the pressure contact member 44 supported by the support 42, were each arranged along the radial direction of the rotating shaft 41. In contrast, in the clamping device 40C of this embodiment, the surface 47 of the pressure contact member 44 and the pair of contact surfaces 46 are arranged along the direction intersecting the radial direction of the rotation axis 41, that is, along the circumferential direction of the rotation axis 41. Furthermore, the arrangement of the pressure contact member 44 and the pair of contact surfaces 46 on the rotation axis 41 and the support 42 is reversed.

[0046] In Figure 11, a pair of contact members 45C are fixed to one side of an inner flange 423 that protrudes from the inside of the support 42. The pair of contact members 45C are arranged coaxially with respect to the central axis A of the rotation shaft 41, and a pair of contact surfaces 46 are formed on each of their opposing surfaces. The pair of contact surfaces 46 are formed in an annular shape at a predetermined distance from the central axis A of the rotation shaft 41 and are facing each other at a constant interval. The contact member 44 is supported on one side near the outer circumference of the disk 43 and extends in the direction of the central axis A of the rotation shaft 41 to reach between the pair of contact surfaces 46. The contact member 44 has the configuration shown in Figure 5 or the configuration shown in Figures 6 to 8 (contact members 44A to 44C), and a pair of front and back surfaces 47 facing the contact surface 46 are aligned with the central axis A of the rotation shaft 41. orthogonal diameters It is possible to advance in that direction.

[0047] In this embodiment as well, by advancing the surfaces 47 on both sides of the pressure contact member 44 and pressing them against the pair of contact surfaces 46, the rotation axis 41 can be restrained without displacing the support 42, resulting in a simple structure while ensuring restraining force and positional accuracy.

[0048] [Other embodiments] It should be noted that the present invention is not limited to the embodiments described above, and any modifications that can achieve the objectives of the present invention are included in the present invention. In the embodiments described above, a contact member 45 or a pressure-contacting member 44 is supported on the outer circumference of a disk 43 fixed to a rotating shaft 41. However, these supports are not limited to the disk 43 but may also be radial spokes or the like. Furthermore, the contact member 45 is not limited to both sides of the pressure-contacting member 44; one side may be a contact portion 43A formed integrally with the disk 43. In addition, an annular contact member 45 supported on a support 42 may be an annular contact portion 42A formed integrally with the support 42. The pair of contact surfaces 46 are not limited to surfaces facing each other on the inside of the pair of contact members 45, but may also be formed as the inner surface of an annular groove. Furthermore, the pressure-contacting member 44 may also be formed integrally with the support 42 or the disk 43. In each of the above embodiments, the pressure-welding members 44, 44A, 44B, and 44C are each flattened annular shapes, but they are not limited to being continuous annular shapes; multiple fragmentary pressure-welding members may be arranged at predetermined intervals in the circumferential direction.

[0049] In each of the above embodiments, two B-axis rotary indexing devices 20 were installed on the B-axis rotation axis 131, and one C-axis rotary indexing device 30 was installed on the C-axis rotation axis 142, but these may be one or any number. In addition, although one clamping device 22 or clamping device 32 is installed on each of the B-axis rotary indexing device 20 and the C-axis rotary indexing device 30, multiple rows of clamping devices may be installed on each. In the embodiments described above, the rotary axis clamping device of the present invention was applied to the B-axis rotary indexing device 20 and the C-axis rotary indexing device 30 of the 5-axis head 10 of a 5-axis machine tool. However, the rotary axis clamping device of the present invention may also be applied to the worktable rotation mechanism of a machine tool or other devices. [Industrial applicability]

[0050] This invention can be used in a rotating shaft clamping device. [Explanation of Symbols]

[0051] 1... Ram, 10... 5-axis head, 11... Spindle, 12... Cutting tool, 13... Spindle head, 131... Rotating axis, 14... Arm body, 141... Arm, 142... Rotating axis, 143... Slip ring rotating axis, 15... Head body, 151... Slip ring case, 20... B-axis rotary indexing device, 21, 31... Drive motor, 22, 32, 40, 40A, 40B, 40C... Clamping device, 30 ...C-axis rotary indexing device, 41...rotating shaft, 42...support, 421...recess, 422...pin, 423...inner flange, 43...disk, 44,44A,44B,44C...pressure contact members, 441...cavity, 442...diaphragm, 443...piston, 444...piezoelectric element, 45,45B,45C...contact members, 42A,43A...contact portion, 46...contact surface, 47...surface, A...central axis.

Claims

1. A rotating axis clamping device for clamping a first member and a second member that are rotatable relative to each other around a predetermined central axis, The first member supports a pair of contact surfaces that are annular in shape at a predetermined distance from the central axis and face each other at a constant interval, and the second member supports a pressure contact member that can be pressed against the pair of contact surfaces, The pressure-contacting member is positioned between a pair of contact surfaces, and the pair of surfaces facing the contact surfaces are capable of extending radially in a direction perpendicular to the central axis. The first member is a rotating shaft, The second member is a support that rotatably supports the rotation shaft, A disk is formed coaxially in the middle portion of the aforementioned rotating shaft. The pair of contact surfaces are formed on the outer edge of the disk and are facing each other in the radial direction of the rotation axis. The aforementioned pressure contact member is a rotating shaft clamping device supported by the support body.

2. A rotating axis clamping device for clamping a first member and a second member that are rotatable relative to each other around a predetermined central axis, The first member supports a pair of contact surfaces that are annular in shape at a predetermined distance from the central axis and face each other at a constant interval, and the second member supports a pressure contact member that can be pressed against the pair of contact surfaces, The pressure-contacting member is positioned between a pair of contact surfaces, and the pair of surfaces facing the contact surfaces are capable of extending radially in a direction perpendicular to the central axis. The first member is a support, The second member is a rotating shaft that is rotatably supported by the support, An annular contact member is formed on the inside of the support, coaxial with the rotation axis. The pair of contact surfaces are formed on the inner edge of the contact member and are facing each other in the radial direction of the rotation axis. The aforementioned pressure contact member is a rotating shaft clamping device supported by the rotating shaft.

3. In the rotating shaft clamping device according to claim 1 or claim 2, The aforementioned pressure-contacting member is a rotating shaft clamping device having a flattened diaphragm that can expand due to the fluid pressure supplied to the inside.

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