Rotation supporting device and supporting mechanism position adjusting mechanism of shaft supporting device

Abstract

A support mechanism (30) for rotatably supporting both axial ends of a screw shaft (21) is provided with: a bearing unit (41) having a moving-side bearing housing (51) and a pair of angular ball bearings (33); a support table (43); and a housing position adjustment mechanism (44) disposed between the bearing unit (41) and the support base (43). The housing position adjustment mechanism (44) is provided with: a support table-side member (61) provided on the support table (43) side; a bearing housing member-side member (62) that is provided on the bearing housing (51) side and that is relatively movable in the axial direction with respect to the support table-side member (61); a belleville spring (70) disposed in a compressed state between opposing axial end surfaces of the support table-side member (61) and the bearing housing member-side member (62); and an O-ring (67) disposed between the facing surfaces of the support table-side member (61) and the bearing housing member-side member (62). As a result, even if the axial length of the rotating shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be damped.

Description

Technical Field

[0001] The present invention relates to a support mechanism position adjustment mechanism for a rotary support device for a rotary shaft such as a support ball screw feed device and a spindle device, and a shaft support device for supporting a shaft. Background Art

[0002] In a ball screw feed device, high axial rigidity is required to maintain the feed accuracy of a screw shaft. Conventionally, as a method of imparting rigidity to the screw shaft of a ball screw device, generally, a plurality of angular contact bearings are combined and preloaded, and they are arranged at one end or both ends of the screw shaft to axially fixedly support the screw shaft. In addition, in consideration of the thermal expansion of the screw shaft, a method of pre-applying a tension in the axial direction to the screw shaft to cause it to elongate by a specified amount is adopted. Patent Document 1 describes the following: By adjusting the axial dimension of a spacer, a tension is pre-applied to a feed screw (screw shaft), and moreover, a pre-tension mechanism is provided. When the feed screw elongates beyond the pre-tension amount due to a temperature rise, this pre-tension mechanism uses a disc spring or the pressure of a fluid to move a bearing in the axial direction and impart a tension to the feed screw.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Utility Model Registration No. 2573982 Summary of the Invention

[0006] Technical Problem to be Solved by the Invention

[0007] However, in a ball screw feed device, the screw shaft with relatively low rigidity may vibrate as the nut moves. In the case of using a disc spring as described in Patent Document 1, there is a problem that such vibration cannot be suppressed.

[0008] Moreover, such a problem exists not only in a ball screw feed device but also in a rotary support device that rotatably supports both axial ends of a rotary shaft by a pair of support mechanisms such as a spindle device.

[0009] The present invention has been made in view of the above problems, and an object thereof is to provide a support mechanism position adjustment mechanism for a rotary support device and a shaft support device that can continuously and stably maintain the axial support rigidity and can attenuate axial vibration even when the axial length of the rotary shaft changes due to the influence of heat.

[0010] Technical Means for Solving the Problem

[0011] The above object of the present invention is achieved by the following structure.

[0012] [1]A rotational support device includes:

[0013] A rotating shaft; and a pair of support mechanisms that respectively support both axial ends of the rotating shaft so as to be rotatable.

[0014] One of the pair of support mechanisms includes:

[0015] A bearing unit including a bearing housing and a bearing that supports the rotating shaft relative to the bearing housing so as to be rotatable and can support an axial load.

[0016] A support table that is penetrated by the rotating shaft or disposed around the rotating shaft; and

[0017] A housing position adjustment mechanism disposed between the bearing unit and the support table.

[0018] The housing position adjustment mechanism includes:

[0019] A support table side member disposed on the support table side and penetrated by the rotating shaft or disposed around the rotating shaft.

[0020] A bearing housing side member disposed on the bearing housing side and penetrated by the rotating shaft or disposed around the rotating shaft and capable of relatively moving axially with respect to the support table side member.

[0021] An elastic member disposed in a compressed state between opposing axial end faces of the support table side member and the bearing housing side member; and

[0022] A damping member disposed between opposing surfaces of the support table side member and the bearing housing side member.

[0023] [2]A support mechanism position adjustment mechanism for a shaft support device is provided in one of a pair of support mechanisms in a shaft support device. The shaft support device includes a shaft and a pair of the support mechanisms provided at both axial ends of the shaft for supporting the shaft.

[0024] One of the pair of support mechanisms has a support body penetrated by the shaft or disposed around the shaft.

[0025] The support mechanism position adjustment mechanism of the shaft support device includes:

[0026] A first member disposed on one of the shaft side and the support body side and capable of being penetrated by the shaft or disposed around the shaft.

[0027] A second component, which is disposed on the other of the shaft side and the support body side, can be penetrated by the shaft or can be arranged around the shaft, and can move axially relative to the first component;

[0028] An elastic component, which is disposed in a compressed state between the opposing axial end faces of the first component and the second component; and

[0029] A damping component, which is disposed between the opposing surfaces of the first component and the second component.

[0030] Advantages of the Invention

[0031] According to the rotational support device of the present invention, even if the axial length of the rotating shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0032] In addition, according to the support mechanism position adjustment mechanism of the shaft support device of the present invention, even if the axial length of the shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated. Description of the Drawings

[0033] Figure 1 is a cross-sectional view of a table feed system of a machine tool of a ball screw feed device according to a first embodiment of the present invention.

[0034] Figure 2 is provided with Figure 1 an enlarged cross-sectional view of a support mechanism of a housing position adjustment mechanism shown.

[0035] Figure 3 is Figure 2 a view in the direction A of

[0036] Figure 4 is a view corresponding to Figure 2 of a ball screw feed device according to a second embodiment of the present invention.

[0037] Figure 5 is a view corresponding to Figure 2 of a modification of a bearing unit in which a pair of angular contact ball bearings are arranged in a back-to-back combination in the first and second embodiments.

[0038] Figure 6 is a view corresponding to Figure 2 of another modification of a bearing unit in which a pair of angular contact ball bearings are arranged side by side in the first and second embodiments.

[0039] Figure 7FIG. (a) is a schematic side view showing a first example of a housing position adjustment mechanism composed of a plurality of pressure chambers, and FIG. (b) is a schematic side view showing a second example of a housing position adjustment mechanism composed of a plurality of pressure chambers.

[0040] Figure 8 FIG. (a) is a schematic side view showing a third example of a housing position adjustment mechanism composed of a plurality of pressure chambers, and FIG. (b) is a schematic side view showing a fourth example of a housing position adjustment mechanism composed of a plurality of pressure chambers.

[0041] Figure 9 is a schematic side view showing a fifth example of a housing position adjustment mechanism composed of a plurality of pressure chambers.

[0042] Figure 10 is along Figure 8 a cross-sectional view taken along line X-X of FIG. (a).

[0043] Figure 11 is a view corresponding to Figure 2 of the ball screw feed device according to the third embodiment of the present invention.

[0044] Figure 12 is a view corresponding to Figure 2 of the ball screw feed device according to the first modification of the third embodiment.

[0045] Figure 13 is a view corresponding to Figure 2 of the ball screw feed device according to the second modification of the third embodiment.

[0046] Figure 14 is a cross-sectional view of a table feed system of a machine tool to which a ball screw feed device according to a modification of the present invention is applied.

[0047] Figure 15 is a cross-sectional view showing a first example of a housing position adjustment mechanism in which a support table is disposed on the axial end side with respect to a bearing unit.

[0048] Figure 16 is a cross-sectional view showing a second example of a housing position adjustment mechanism in which a support table is disposed on the axial end side with respect to a bearing unit.

[0049] Figure 17 is a cross-sectional view showing a third example of a housing position adjustment mechanism in which a support table is disposed on the axial end side with respect to a bearing unit.

[0050] Figure 18 is a cross-sectional view showing a fourth example of a housing position adjustment mechanism in which a support table is disposed on the axial end side with respect to a bearing unit.

[0051] Figure 19It is a cross-sectional view showing the rotary bearing device according to the present invention.

[0052] Figure 20 It is a cross-sectional view showing the rotary bearing device according to the present invention.

[0053] Figure 21 It is a cross-sectional view showing the shaft bearing device applying the position adjustment mechanism of the support mechanism according to the present invention.

[0054] Figure 22 It is Figure 21 An enlarged view of part XXII of Specific embodiments

[0055] Hereinafter, each embodiment of the ball screw feed device as an example of the rotary bearing device and the shaft bearing device according to the present invention will be described in detail based on the drawings.

[0056] (First embodiment)

[0057] Figure 1 It shows the table feed system of a machine tool applying the ball screw feed device of this embodiment. In addition, for Figures 1 to 3 , the axial direction of the screw shaft 21 of the ball screw feed device 20 ( Figure 1 The left-right direction of Figure 1 The direction parallel to the mounting surface 1a of the base 1 and orthogonal to the axial direction of the screw shaft 21 ( Figure 1 The direction perpendicular to the paper surface of Figure 2 And Figure 2 The corresponding directions in the respective figures, the dashed lines indicate the bolt fastening parts.

[0058] The table feed system 10 is configured to include a moving table 11 fixed to the nut 23 of the ball screw feed device 20. By driving the screw shaft 21 of the ball screw feed device 20 by the drive motor 12, the moving table 11 can move freely in the X direction. On the moving table 11, a pair of linear guides 13 are provided on both sides in the Y direction with respect to the ball screw feed device 20 ( Figure 1 Only one is shown in the figure). Each linear guide 13 includes: a guide rail 15, which is disposed on the base 1 in parallel with the screw shaft 21 with a track mounting table 14 interposed therebetween; and two sliders 16, which are fixed to the lower surface of the moving table 11 and straddle the guide rail 15. And, by rotating the screw shaft 21 using the drive motor 12, the moving table 11 is guided by the pair of linear guides 13 and reciprocates linearly together with the nut 23.

[0059] The ball screw feed device 20 includes: a screw shaft 21 having a helical thread groove 21b formed on its outer peripheral surface; a nut 23 disposed around the screw shaft 21, having a helical thread groove (not shown) formed on its inner peripheral surface, and being fitted with a nut housing 22 fixed to the lower surface of the moving table 11; and a plurality of balls (not shown) that are rotatably disposed between the thread groove of the nut 23 and the thread groove 21b of the screw shaft 21.

[0060] The screw shaft 21 includes: a large-diameter portion 24 formed at the axial center and having a thread groove 21b; and small-diameter portions 25 formed at both axial ends of the large-diameter portion 24. An external thread 25a is formed on the outer peripheral surface of the tip side of the small-diameter portion 25. In addition, a small-diameter shaft portion 27 is provided at the tip of one side (the right side in the figure) of the screw shaft 21. The rotating shaft 12a of the drive motor 12 is connected to the small-diameter shaft portion 27 via a coupling 28.

[0061] In addition, one side of the screw shaft 21 to which the drive motor 12 is connected is rotatably supported by a first support mechanism 30, and the other side (the left side in the figure) of the screw shaft 21 is rotatably supported by a second support mechanism 40.

[0062] The first support mechanism 30 includes: a fixed-side bearing housing 31 fixed to the base 1, and a pair of angular contact ball bearings 33, 33 arranged in a face-to-face combination that rotatably supports the screw shaft 21 relative to the fixed-side bearing housing 31. Each of the pair of angular contact ball bearings 33, 33 includes: an outer ring 34 fitted into the fixed-side bearing housing 31, an inner ring 35 fitted onto the small-diameter portion 25 of the screw shaft 21, and a plurality of balls 36 that are rotatably disposed between the outer ring 34 and the inner ring 35 at a contact angle.

[0063] For the pair of angular contact ball bearings 33, 33, the outer ring 34 of the angular contact ball bearing 33 on the inner axial side abuts against the inward flange 31a of the fixed-side bearing housing 31, and the outer ring 34 of the angular contact ball bearing 33 on the outer axial side is fixed by an outer ring pressing member 37 fastened to the fixed-side bearing housing 31. In addition, the inner ring 35 of the angular contact ball bearing 33 on the inner axial side abuts against the step portion 21a between the large-diameter portion 24 and the small-diameter portion 25 of the screw shaft 21, and the inner ring 35 of the angular contact ball bearing 33 on the outer axial side is fastened by a fastening nut 38a screwed onto the external thread 25a.

[0064] Therefore, the first support mechanism 30 supports the screw shaft 21 in a state where the axial position of the screw shaft 21 is fixed.

[0065] Also refer to Figure 2 and Figure 3, the second support mechanism 40 includes: a bearing unit 41 disposed at the other end of the lead screw shaft 21; a support table 43 fixed to the base 1 at a position closer to the axial center side than the bearing unit 41; and a housing position adjustment mechanism 60 disposed between the bearing unit 41 and the support table 43. A through hole 43a through which the lead screw shaft 21 passes is provided in the support table 43.

[0066] The bearing unit 41 includes: a moving side bearing housing 51 and a pair of angular contact ball bearings 53, 53 that support the lead screw shaft 21 so as to be rotatable relative to the moving side bearing housing 51.

[0067] The pair of angular contact ball bearings 53, 53 includes: an outer ring 54 embedded in the moving side bearing housing 51, an inner ring 55 externally fitted to the small diameter portion 25 of the lead screw shaft 21, and a plurality of balls 56 that are rotatably disposed between the outer ring 54 and the inner ring 55 at a contact angle.

[0068] In the pair of angular contact ball bearings 53, 53, the outer ring 54 of the axially inner angular contact ball bearing 53 is abutted against the inward flange 51a of the moving side bearing housing 51, and the outer ring 54 of the axially outer angular contact ball bearing 53 is fastened by an outer ring pressing member 47 fixed to the moving side bearing housing 51 by fastening. Each outer ring 54, 54 is axially positioned relative to the moving side bearing housing 51. In addition, the inner ring 55 of the angular contact ball bearing 53 disposed axially outside is fastened by a fastening nut 38b screwed with the external thread 25a via a spacer 48.

[0069] That is, the pair of angular contact ball bearings 53, 53, the moving side bearing housing 51, and the outer ring pressing member 47 can be unitized into the bearing unit 41 in a state where a predetermined preload is applied to the pair of angular contact ball bearings 53, 53 arranged in a face-to-face combination, and the bearing unit 41 can be easily installed on the lead screw shaft 21 and the housing position adjustment mechanism 60 respectively. In this structure, the moving side bearing housing 51 can also be integrated with the bearing housing side member 62 as needed.

[0070] The housing position adjustment mechanism 60 includes: a support table side member 61 provided on the support table 43 side and penetrated by the lead screw shaft 21; and a bearing housing side member 62 provided on the moving side bearing housing 51 side and capable of relatively moving axially with respect to the support table side member 61. The support table side member 61 and the bearing housing side member 62 are axially opposed to each other.

[0071] The annular portion 61a protruding toward the support table 43 of the support table side member 61 is fitted into the through hole 43a of the support table 43 and fixed to the support table 43 by a plurality of bolts (not shown). The annular portion 62a protruding toward the moving side bearing housing 51 of the bearing housing side member 62 is fitted into the inward flange 51a and fixed to the moving side bearing housing 51 by a plurality of bolts 63 (refer to Figure 3 ).

[0072] In addition, a bottomed annular recess 64 that opens toward the support table side member 61 side (one axial side) is provided on the side surface of the bearing housing side member 62 on the support table side member 61 side. On the other hand, an annular protrusion 65 that protrudes into the annular recess 64 toward the bearing housing side member 62 side (the other axial side) is provided on the side surface of the support table side member 61 on the bearing housing side member 62 side. The annular recess 64 and the annular protrusion 65 are fitted in a manner that allows sliding in the axial direction, and an annular pressure chamber 66 is formed between the bottom surface, the inner facing surface 64a, and the outer facing surface 64b of the annular recess 64 and the top surface of the annular protrusion 65.

[0073] Moreover, in the pressure chamber 66, between the opposing axial end faces of the support table side member 61 and the bearing housing side member 62, that is, between the bottom surface of the annular recess 64 and the top surface of the annular protrusion 65, a plurality of disc springs 70, which are elastic members, are arranged in a compressed state. When the plurality of disc springs 70 function as a series spring, as Figure 2 shown, they are axially overlapped in such a way that the convex side surfaces of adjacent disc springs 70 face each other and the concave side surfaces face each other. In addition, when the plurality of disc springs 70 function as a parallel spring, although not shown, the disc springs 70 are arranged to overlap in the same orientation in the axial direction.

[0074] Furthermore, holes for suction and exhaust (not shown) are provided in the bearing housing side member 62 to allow air to freely enter and exit the pressure chamber 66.

[0075] Further, an O-ring 67 as a damping member is assembled between the opposing surfaces of the support table side member 61 and the bearing housing side member 62, that is, between the outward-facing surface 65a of the annular protrusion 65 and the inward-facing surface 64a of the annular recess 64, and between the inward-facing surface 65b of the annular protrusion 65 and the outward-facing surface 64b of the annular recess 64. Specifically, the O-ring 67 is disposed in an annular sealing groove 68 formed on the outward-facing surface 65a and the inward-facing surface 65b of the annular protrusion 65, and is in sliding contact with the inward-facing surface 64a and the outward-facing surface 64b of the opposing annular recess 64, sealing the radial clearance between the outward-facing surface 65a of the annular protrusion 65 and the inward-facing surface 64a of the annular recess 64, and the radial clearance between the inward-facing surface 65b of the annular protrusion 65 and the outward-facing surface 64b of the annular recess 64. In addition, the sealing groove 68 may also be formed on the inward-facing surface 64a and the outward-facing surface 64b of the annular recess 64. Further, one O-ring 67 and sealing groove 68 are respectively disposed between each pair of opposing surfaces, but multiple ones may also be disposed. From the perspective of preventing wear, a surface treatment such as wear resistance may also be applied to the O-ring 67.

[0076] In addition, a rotation prevention mechanism 75 for preventing relative rotation between the support table side member 61 and the bearing housing side member 62 is provided. Specifically, for example, in the bearing housing side member 62, through holes 77 penetrating in the radial direction are formed at at least one position in the circumferential direction, and the tip of the positioning pin 76 protrudes from the inward-facing surface 64a of the annular recess 64 through the through hole 77. Moreover, the tip of the positioning pin 76 is inserted into a long hole 78 formed in the axial direction on the outward-facing surface 65a of the annular protrusion 65 of the support table side member 61 in such a manner that the bearing housing side member 62 can move axially. In addition, the positioning pin 76 may be replaced by inserting a positioning key (not shown) in the rotational direction having the same rotation prevention function and capable of moving the bearing housing side member 62 axially into the long hole 78.

[0077] After arranging a plurality of disc springs 70 in the pressure chamber 66, such a housing position adjustment mechanism 60 fastens the fastening nut 38b, thereby pressing the bearing housing side member 62 toward the support table side member 61 via a pair of angular contact ball bearings 53, 53 and the moving side bearing housing 51, thus compressing the plurality of disc springs 70 and applying a pressure in the direction of the lead screw shaft to the plurality of disc springs 70.

[0078] On the other hand, since the support table side member 61 is fixed to the base 1 via the support table 43, the bearing housing side member 62 and the moving side bearing housing 51 are pressed in the left direction in the figure by the pressure of the plurality of disc springs 70 arranged in a compressed state in the pressure chamber 66. Thus, a state of applying tension to the lead screw shaft 21 in advance toward Figure 1 , Figure 2 the upper left is achieved.

[0079] In addition, the pressure of the plurality of disc springs 70 disposed in the pressure chamber 66 can be controlled to an arbitrary magnitude by the tightening amount of the fastening nut 38b. That is, the magnitude of the axial load applied to the lead screw shaft 21 by the fastening nut 38b can be set to an arbitrary magnitude.

[0080] Moreover, the magnitude of the axial load applied to the lead screw shaft 21 by the plurality of disc springs 70 can be set in consideration of the deformation caused by the temperature rise of the plurality of disc springs 70 during the operation of the ball screw feed device 20, in addition to the setting based on the tightening amount of the fastening nut 38b.

[0081] Next, the operation of the ball screw feed device 20 of the present embodiment will be described.

[0082] In the ball screw feed device 20, when the lead screw shaft 21 is rotationally driven by the drive motor 12 to cause the moving table 11 fixed to the nut 23 to perform a reciprocating linear motion, the drive motor 12, the angular contact ball bearings 33, 53, the nut 23, etc. generate heat, and the temperature of the ball screw feed device 20 gradually rises, and the lead screw shaft 21 axially elongates due to thermal expansion.

[0083] When the lead screw shaft 21 axially elongates due to thermal expansion, in Figure 1 the ball screw feed device 20 of the present embodiment shown, the right end portion of the lead screw shaft 21 is fixed to the fixed-side bearing housing 31 via the angular contact ball bearings 33, 33, so the lead screw shaft 21 elongates in the left direction. When the lead screw shaft 21 axially (left direction) elongates due to the influence of heat, the bearing unit 41 and the bearing housing side member 62 move in the same direction following the axial elongation of the lead screw shaft 21 caused by thermal expansion by the pressure of the plurality of disc springs 70 disposed in the pressure chamber 66.

[0084] In the present embodiment, it is designed such that even when the lead screw shaft 21 axially elongates, the plurality of disc springs 70 continue to press the bearing unit 41 and the bearing housing side member 62 to the left. Therefore, it is possible to axially move the pair of angular contact ball bearings 53, 53 to maintain the axial support rigidity and stabilize the axial rigidity of the ball screw feed device 20.

[0085] In addition, the O-ring 67 of the present embodiment functions as a damping mechanism. That is, when machining a workpiece placed on the moving table 11, due to the vibration generated by the moving table 11, the lead screw shaft 21 with relatively low rigidity also tends to vibrate. The vibration of the lead screw shaft 21 is transmitted to the bearing housing side member 62 via the pair of angular contact ball bearings 33, 33 and the moving side bearing housing 51, but the vibration of the bearing housing side member 62 is attenuated by the O-ring 67 between the bearing housing side member 62 and the support table side member 61. Therefore, the vibration of the lead screw shaft 21 can also be attenuated, and the disorder of the machining surface quality of the workpiece placed on the moving table 11 can be suppressed.

[0086] At this time, the O-ring 67 disposed between the bearing housing side member 62 and the support table side member 61 can not only attenuate the vibration of the lead screw shaft 21 in the axial direction, but also attenuate the vibration of the lead screw shaft 21 in the radial direction.

[0087] In addition, when the axial elongation of the lead screw shaft 21 occurs, even when vibration is generated due to the elastic deformation during the recovery of the disc spring 70 from the compressed state, the O-ring 67 can attenuate this vibration.

[0088] Furthermore, although not shown, the support table side member 61 may be integrally formed with the support table 43, and the bearing housing side member 62 may be integrally formed with the moving side bearing housing 51.

[0089] (Second Embodiment)

[0090] Next, with reference to Figure 4 the ball screw feed device according to the second embodiment of the present invention will be described. In addition, in the present embodiment, the second support mechanism 40 further has another housing position adjustment mechanism 160, which is different from the first embodiment in this regard.

[0091] That is, in the second support mechanism 40 of the second embodiment, another housing position adjustment mechanism 160 is further provided, which is disposed adjacent to the housing position adjustment mechanism 60 between the bearing unit 41 and the support table 43.

[0092] Another housing position adjustment mechanism 160 includes: another support table side member 161, which is provided on the support table 43 side and is penetrated by the lead screw shaft 21; another bearing housing side member 162, which is provided on the bearing housing 51 side and is penetrated by the lead screw shaft 21 and can move relatively axially with respect to another support table side member 161; and a plurality of disc springs 70, which are arranged in a compressed state in a pressure chamber 166 formed between another support table side member 161 and another bearing housing side member 162. That is, the second support mechanism 40 has two housing position adjustment mechanisms 60, 160 with a series structure arranged in series along the axial direction.

[0093] As Figure 4 shown, in the other housing position adjustment mechanism 160 as well, the other bearing housing side member 162 has an annular recess 164, the other support table side member 161 has an annular projection 165 that is fitted in the annular recess 164 so as to be axially slidable, and a plurality of disc springs 70 are arranged in a compressed state in a pressure chamber 166 formed between the annular recess 164 and the annular projection 165.

[0094] In addition, in the present embodiment, an annular portion 161a protruding toward the support table 43 of the other support table side member 161 is fitted into a through hole 43a of the support table 43 and fixed to the support table 43 by a plurality of bolts (not shown). And, the support table side member 61 of the housing position adjustment mechanism 60 and the other bearing housing side member 162 of the other housing position adjustment mechanism 160 are formed of one member or are configured integrally by connecting the two.

[0095] In this way, by arranging the two housing position adjustment mechanisms 60 and 160 in series along the axial direction, even when the elongation of the lead screw shaft is greater, the axial rigidity of the ball screw feed device 20 can be stably maintained. In addition, the axial centering property and coaxiality can be improved.

[0096] In addition, the other housing position adjustment mechanism 160 is not limited to Figure 4 the same structure as the housing position adjustment mechanism 60 as shown. As long as it has a pressure generating unit that is housed in a pressure chamber 166 formed between the other support table side member 161 and the other bearing housing side member 162 in a compressed state, it may have other structures. For example, as the pressure generating unit, a working fluid that has an elastic effect when an external force acts and whose rigidity has been industrially confirmed may be filled in the pressure chamber 166 in a compressed state.

[0097] In addition, the second support mechanism 40 may have three or more housing position adjustment mechanisms in addition to the two housing position adjustment mechanisms 60 and 160, as long as the structure is such that a plurality of housing position adjustment mechanisms are arranged in series along the axial direction.

[0098] Other structures and operations are the same as those of the first embodiment.

[0099] In addition, in the first or second embodiment, a pair of angular contact ball bearings of the bearing unit applicable to the second support mechanism are arranged in a face-to-face combination, but the present invention is not limited thereto. That is, the pair of angular contact ball bearings 53, 53 may also be arranged in various support modes such as Figure 5 the back-to-back combination as shown, Figure 6 the side-by-side combination as shown, etc. In addition, as Figure 5As shown, when a pair of angular contact ball bearings 53, 53 are arranged in a back-to-back combination, an inner ring spacer 49 may also be arranged between the step between the large-diameter portion 24 and the small-diameter portion 25 of the lead screw shaft 21 and the inner ring 55 of the angular contact ball bearing 53 on the axially inner side.

[0100] In addition, the pair of angular contact ball bearings 33, 33 of the first support mechanism are also arranged in a face-to-face combination, but they can also be arranged in various support methods such as back-to-back combination and side-by-side combination.

[0101] In addition, although not shown, the angular contact ball bearings 33, 53 do not necessarily consist of two angular contact ball bearings, and can also consist of three or more angular contact ball bearings.

[0102] Moreover, in the above-described embodiment, the other housing position adjustment mechanism 160 and the housing position adjustment mechanism 60 are arranged adjacent to each other in the axial direction, but it is not limited thereto, and it can also be a structure arranged in parallel adjacent to the housing position adjustment mechanism 60 in the radial direction.

[0103] Thereby, the axial dimension of the ball screw feed device 20 can be suppressed, and in a state where an axial load larger than that when a separate housing position adjustment mechanism is arranged is generated, the axial rigidity of the ball screw feed device 20 can be maintained.

[0104] In addition, although in the above-described embodiment, the pressure chamber 66 is formed in a ring shape by the annular recess 64 and the annular protrusion 65, a plurality of recesses and protrusions can also be formed in the circumferential direction to form a plurality of pressure chambers. In this case, the following structure can be adopted, that is, elastic members are respectively arranged in the plurality of pressure chambers, and in addition, an O-ring is arranged between the inner circumferential surface of the recess and the outer circumferential surface of the protrusion.

[0105] For example, as shown in Figure 7 (a), the pressure chambers 66 at four positions are arranged around the lead screw shaft 21 in the circumferential direction, or as shown in Figure 7 (b), two pressure chambers 66 arranged side by side adjacent to each other in the radial direction are provided at four positions in the circumferential direction, that is, a total of 8 pressure chambers 66 are arranged around the lead screw shaft 21. Or, as shown in Figure 8 (a), the pressure chambers 66 at two positions in the circumferential direction, that is, the pressure chambers 66 located on both sides in the width direction (Y direction) with respect to the lead screw shaft 21 are arranged around the lead screw shaft 21, or as shown in Figure 8 (b), three pressure chambers 66 arranged adjacent to each other in the radial direction (in this example, the width direction) are provided at two positions in the circumferential direction, that is, a total of 6 pressure chambers 66 are arranged around the lead screw shaft 21. In this case, the height dimensions of the support table side member 61 and the bearing housing side member 62 can be suppressed.

[0106] And, as shown in Figure 9As shown, the pressure chambers 66 may also be disposed around the lead screw shaft 21 at two positions in the circumferential direction, that is, the pressure chambers 66 on both the upper and lower sides in the vertical direction with respect to the lead screw shaft 21. In this case, the width dimensions of the support base side member 61 and the bearing housing side member 62 can be suppressed.

[0107] Here, Figure 10 is a schematic cross-sectional view along the Figure 8 X-X line of (a). In this case, the two pressure chambers 66 are each composed of a concave portion 64x and a convex portion 65x.

[0108] In addition, in the figure, the convex portion 65x is integrally formed with the base portion of the support base side member 61, but it may also be formed separately from the base portion and joined.

[0109] It should be noted that for the plurality of pressure chambers 66, as long as the bearing unit 41 and the bearing housing side member 62 can stably move in the same direction following the axial elongation of the lead screw shaft 21 caused by thermal expansion, they can be arbitrarily arranged. Specifically, it is preferably arranged point-symmetrically or line-symmetrically on a plane orthogonal to the lead screw shaft 21. In addition, the plurality of pressure chambers 66 may also be arranged offset in the axial direction.

[0110] In addition, the support base side member 61 and the bearing housing side member 62 are not limited to being composed of a single member, and may also be divided and formed in a manner of being arranged around the lead screw shaft 21 according to the layout of the pressure chambers 66. Moreover, the support base side member 61 and the bearing housing side member 62 as single members may also be configured to be arranged around the lead screw shaft 21 and have a part of the circumference open and divided.

[0111] For example, in Figure 8 (b), the two support base side members 61 and the bearing housing side members 62 are configured to be divided in the width direction with respect to the lead screw shaft 21.

[0112] Moreover, similar to the above-described another housing position adjustment mechanism 160, the pressure generating units in the plurality of pressure chambers 66 are not limited to having the same structure for all, that is, elastic members arranged in a compressed state. The pressure generating unit in any one of the pressure chambers 66 may also be other structures such as a working fluid filled in the pressure chamber 66 in a compressed state.

[0113] In addition, the concave portion or convex portion constituting the pressure chamber 66 is not limited to a circular cross-section, and may be set to any shape such as a rectangle. And the cross-sectional dimensions and axial dimensions of the plurality of pressure chambers 66 can be arbitrarily configured.

[0114] (Third Embodiment)

[0115] In the housing position adjustment mechanism 60 of the above-described embodiments and modifications, when the lead screw shaft 21 extends in the axial direction, the volume of the pressure chamber 66 increases, and the plurality of disc springs 70 in a compressed state press the bearing unit 41 and the bearing housing side member 62 to the left while gradually decreasing the pressure. As a result, the pair of angular contact ball bearings 53, 53 move axially, thereby maintaining the axial support rigidity of the lead screw shaft 21.

[0116] However, in the third embodiment, the Figure 11 shown housing position adjustment mechanism 60 is used to maintain the axial support rigidity of the lead screw shaft 21. Specifically, when the lead screw shaft 21 extends in the axial direction, the bearing unit 41 and the bearing housing side member 62 move to the left via the pair of angular contact ball bearings 53, 53 that move together with the lead screw shaft 21, and the volume of the pressure chamber 66 decreases. On the other hand, when the pressure of the plurality of disc springs 70 gradually increases, the bearing unit 41 and the bearing housing side member 62 are pressed to the right. Therefore, by adjusting the volume of the pressure chamber 66 and the pressure of the plurality of disc springs 70 in a manner that allows the axial elongation of the lead screw shaft 21, the axial support rigidity of the lead screw shaft 21 can be maintained.

[0117] In this case, the support base side member 61 has: a small-diameter cylindrical portion 61c that extends from the small-diameter portion of the annular base portion 61b mounted on the support base 43 toward the bearing housing 51 side; and an outward flange portion 61d that extends from the tip portion of the small-diameter cylindrical portion 61c toward the outer diameter side. The bearing housing side member 62 has: a large-diameter cylindrical portion 62c that extends from the large-diameter portion of the annular base portion 62b mounted on the moving-side bearing housing 51 toward the support base 43 side; and an inward flange portion 62d that extends from the tip portion of the large-diameter cylindrical portion 62c toward the inner diameter side.

[0118] The outward flange portion 61d of the support base side member 61 can move axially relative to between the annular base portion 62b and the inward flange portion 62d of the bearing housing side member 62, and its outer peripheral surface is in sliding contact with the inner peripheral surface of the large-diameter cylindrical portion 62c via an O-ring 67. In addition, the inward flange portion 62d of the bearing housing side member 62 can move axially relative to between the annular base portion 61b and the outward flange portion 61d of the support base side member 61, and its inner peripheral surface is in sliding contact with the outer peripheral surface of the small-diameter cylindrical portion 61c via an O-ring 67. Therefore, the pressure chamber 66 is formed by an annular space defined by the small-diameter cylindrical portion 61c and the outward flange portion 61d of the support base side member 61, and the large-diameter cylindrical portion 62c and the inward flange portion 62d of the bearing housing side member 62, and a plurality of disc springs 70 are filled in the pressure chamber 66 in a slightly compressed state.

[0119] Note that holes for suction and exhaust (not shown) are provided in the small-diameter cylindrical portion 61c of the bearing housing side member 62 so that air can freely enter and exit the pressure chamber 66.

[0120] By forming the pressure chamber 66 in this way, when the lead screw shaft 21 axially elongates due to thermal expansion, the pair of angular contact ball bearings 53, 53, the bearing housing 51, and the bearing housing side member 62 move to the left in the figure while compressing the plurality of disc springs 70 in the pressure chamber 66, thereby maintaining the axial support rigidity of the lead screw shaft 21.

[0121] In addition, the O-ring 67 assembled between the inner peripheral surface of the inward flange portion 62d and the outer peripheral surface of the small-diameter cylindrical portion 61c, and between the outer peripheral surface of the outward flange portion 61d and the inner peripheral surface of the large-diameter cylindrical portion 62c functions as a damping mechanism, and can damp the vibration generated in the lead screw shaft 21.

[0122] In addition, the support table side member 61 and the bearing housing side member 62 can each be composed of a single member, but as Figure 11 shown, considering the assemblability, it is also possible to be composed of two members 91, 92, 93, 94 in a state of sandwiching the O-ring 67.

[0123] In addition, one O-ring 67 and one sealing groove 68 are respectively arranged between each pair of opposing surfaces, but multiple ones can also be arranged.

[0124] In addition, instead of Figure 11 , the support table side member 61 has a large-diameter cylindrical portion and an inward flange portion, and the bearing housing side member 62 has a small-diameter cylindrical portion and an outward flange portion, thereby forming a pressure chamber.

[0125] Moreover, in such a housing position adjustment mechanism 60, the pair of angular contact ball bearings 53, 53 can be arranged in a face-to-face combination as Figure 11 shown, or in a back-to-back combination as Figure 12 shown, or in various support forms such as a side-by-side combination. In addition, although not shown, the pair of angular contact ball bearings do not necessarily consist of two angular contact ball bearings, and can also be composed of three or more ball bearings.

[0126] In addition, in the housing position adjustment mechanism 60 of the third embodiment, as Figure 13 shown, similar to the second embodiment, the second support mechanism 40 can also be formed in a series structure in which the housing position adjustment mechanism 60 and another housing position adjustment mechanism 160 are arranged in series along the axial direction between the bearing unit 41 and the support table 43.

[0127] In this case, the other support base side member 161 of the other housing position adjustment mechanism 160 also has an annular base portion 161b, a small-diameter cylindrical portion 161c, and an outward flange portion 161d, and the other bearing housing side member 162 also has an annular base portion 162b, a large-diameter cylindrical portion 162c, and an inward flange portion 162d. In addition, the other support base side member 161 and the other bearing housing side member 162 of the other housing position adjustment mechanism 160 are each composed of two members 191, 192, 193, 194. In addition, the support base side member 61 of the housing position adjustment mechanism 60 and the other bearing housing side member 162 of the other housing position adjustment mechanism 160 are connected to each other and configured as an integral body.

[0128] In addition, similar to the second embodiment, the second support mechanism 40 may be configured such that a plurality of housing position adjustment mechanisms are arranged in series in the axial direction, or may be arranged in parallel in the radial direction.

[0129] Furthermore, the present invention is not limited to the above-described embodiments, and can be appropriately deformed, improved, etc. In addition, the embodiments and various modification examples described in this specification can be combined and applied within the range where they can be implemented.

[0130] For example, in the above-described embodiment, a disc spring is applied as the elastic member, but it is not limited thereto, and a helical spring may also be used.

[0131] In addition, as the damping member, any material or structure that is disposed between the opposing surfaces of the support base side member and the bearing housing side member and has damping ability can be used, and it is not limited to the O-ring described in the above embodiment.

[0132] For example, the damping member is not limited to a circular cross-section such as an O-ring, and a member having a flat rectangular cross-section or other members having an appropriate cross-sectional shape can also be used.

[0133] In addition, the damping member is not limited to an annular member such as an O-ring, and as long as it can achieve damping, it can also be divided in the circumferential direction. In addition, these divided members can be arranged along the axial direction respectively, or can be arranged obliquely with respect to the axial direction like a spiral.

[0134] In addition, an O-ring is generally made of a rubber material, but it is not limited thereto, and any material having damping ability can be used, for example, it can also be made of resin or the like. And in the above embodiment, the O-ring is disposed in a sealing groove formed on either of the opposing surfaces of the support base side member and the bearing housing side member, but it can also be directly disposed on the opposing surface without having a sealing groove. Such a damping member can also be integrally formed on either or both of the opposing surfaces of the support base side member and the bearing housing side member by direct molding or the like.

[0135] Furthermore, the support table only needs to be structured to directly or indirectly support the support table side member of the housing position adjustment mechanism, and is not limited to the structure penetrated by the rotating shaft as in the above-described embodiment. It may also be a structure arranged around the rotating shaft and can be designed into any shape.

[0136] (Applied to another ball screw feeding device)

[0137] In addition, in Figure 1 the ball screw feeding device 20, the drive motor 12 is connected to one side ( Figure 1 the right side in Figure 14 ) of the lead screw shaft 21 supported by the first support mechanism 30, but the present invention is not limited thereto. That is, it may also be like Figure 14 the ball screw feeding device 20 in

[0138] wherein the drive motor 12 is connected to the other side (

[0139] the left side in

[0140] ) of the lead screw shaft 21 supported by the second support mechanism 40.

[0141] In this case, the drive motor 12 is fixed to the base 1 and supported by another support table 85 penetrated by the lead screw shaft 21. In addition, the tip of the small-diameter shaft portion 27 is arranged separately from the rotating shaft 12a of the drive motor 12 within the coupling 28 so that the small-diameter shaft portion 27 can move axially when the lead screw shaft 21 axially elongates due to thermal expansion. Figure 15 and Figure 16 shown, the support table 43 is provided at a position closer to the axial end side than the bearing unit 41. In this case, it is only necessary to directly or indirectly mount the support table side member 61 on the support table 43, and directly or indirectly mount the bearing housing side member 62 on the bearing housing 51. In addition, the spacer 48a disposed between the inner ring 55 and the fastening nut 38b passes through the through-hole 43a of the support table 43, the inside of the support table side member 61, and the bearing housing side member 62.

[0142] Also, in Figure 17 and Figure 18 In the manner shown, the support table 43 is disposed at a position closer to the axial end side than the bearing unit 41. On the other hand, the support table 43 is fixed to the support table side member 61 disposed on the axial center side with respect to the bearing unit 41 through the outer cylinder portion 43b. The outer cylinder portion 43b extends axially from the main body portion having the through hole 43a and surrounds the periphery of the housing position adjustment mechanism 60. Also in this case, the support table side member 61 may be directly or indirectly mounted on the support table 43, and the bearing housing side member 62 may be directly or indirectly mounted on the bearing housing 51. In addition, the spacer 48a disposed between the inner ring 55 and the fastening nut 38b passes through the through hole 43a of the support table 43.

[0143] (Applications other than ball screw feed devices)

[0144] In addition, in the above-described embodiment, the ball screw feed device has been described. However, the present invention can be applied not only to the ball screw feed device but also to a rotary support device that rotatably supports both axial end portions of a rotating shaft by a pair of support mechanisms. That is, in the case where the axial length of the rotating shaft changes due to the influence of heat, it can be configured to use the housing position adjustment mechanism as in the above-described embodiment, and it is possible to continuously and stably maintain the axial support rigidity of the rotating shaft and attenuate the axial vibration.

[0145] For example, as Figure 19 shown, the rotary support device 120 includes a rotating shaft 121 and a pair of support mechanisms 30, 40 that rotatably support both axial end portions of the rotating shaft 121.

[0146] The support mechanism 30 includes: a bearing housing 31 fixed to the base 1; and bearings 33, 33 that rotatably support the rotating shaft 121 with respect to the bearing housing 31, that is, a pair of angular contact ball bearings 33, 33 arranged in a face-to-face combination.

[0147] In addition, the support mechanism 40 includes: a bearing unit 41 having a bearing housing 51 and bearings 53, 53 that rotatably support the rotating shaft 121 with respect to the bearing housing 51 and can support an axial load, that is, a pair of angular contact ball bearings 53, 53 arranged in a face-to-face combination; a support table 43 disposed on the axial center side with respect to the bearing unit 41 and penetrated by the rotating shaft 121; and a housing position adjustment mechanism 60 disposed between the bearing unit 41 and the support table 43.

[0148] Furthermore, the housing position adjustment mechanism 60 includes: a support table side member 61 provided on the support table 43 side and penetrated by the rotating shaft 121; a bearing housing side member 62 provided on the bearing housing 51 side, penetrated by the rotating shaft 121, and capable of moving relative to the support table side member 61 in the axial direction; an elastic member 70 disposed in a compressed state between the opposed axial end faces of the support table side member 61 and the bearing housing side member 62; and an O-ring (damping member) 67 disposed between the opposed surfaces of the support table side member 61 and the bearing housing side member 62.

[0149] In addition, in Figure 19 parts denoted by the same reference numerals as those in the above-described embodiment are substantially the same, and thus the description thereof is omitted or simplified. In addition, various structures described in the ball screw feed device 20 can also be applied to the rotary support device, achieving the same effects.

[0150] In addition, each of the bearings 33 and 53 of the pair of support mechanisms 30 and 40 of the rotary support device 120 described above may be an angular contact ball bearing as in the above-described embodiment, but is not limited thereto, and may also be a roller bearing or a sliding bearing capable of supporting an axial load. By using a bearing capable of supporting such an axial load, particularly in the support mechanism 40, the elastic member 70 can be compressed via the bearing by tightening the fastening nut 38b as in the above-described embodiment.

[0151] In addition, in Figure 19 it is configured such that the second support mechanism 40 having the housing position adjustment mechanism 60 supports the end of the rotating shaft 121, but as Figure 20 shown, it may also be configured such that the second support mechanism 40 having the housing position adjustment mechanism 60 supports the rotating shaft 121 at a position closer to another support table 85 of the support drive motor 12.

[0152] For example, when the rotary support device 120 shown in Figure 20 is applied to a spindle device that rotates a tool in a machine tool, by mounting a tool at the end of the rotating shaft 121 supported by the support mechanism 30, the axial support rigidity of the rotating shaft 121 can be continuously and stably maintained, and the axial positioning of the tool can be reliably performed, enabling high-precision machining.

[0153] In addition, in Figure 19 and Figure 20 in the rotary support device 120 shown, the drive motor 12 does not necessarily need to be arranged coaxially with the rotating shaft 121. For example, the power of the drive motor can also be transmitted to the rotating shaft 121 via a pulley, a gear train, etc.

[0154] In addition, the drive motor 12 is not limited to a separate motor arranged coaxially with the rotary shaft 121. For example, a built-in motor may be directly formed on the rotary shaft 121.

[0155] In addition, for the rotary support device 120, as the support body, it may also be a housing shell formed by integrating the bearing housing 31 of the first support mechanism 30 and the support table 43 of the second support mechanism 40.

[0156] In addition, in a rotary support device other than the ball screw feed device, as Figures 15 to 18 shown, the support table may also be arranged on the axial end side with respect to the bearing unit.

[0157] In addition, in the above-described embodiment, the housing position adjustment mechanism has been described as a mechanism for adjusting the axial position of the bearing housing that supports the rotary shaft. However, the present invention is not limited thereto, and it can be applied as a support mechanism position adjustment mechanism for a shaft support device. That is, the shaft is not limited to a rotary shaft, and in addition, the support mechanism is not limited to a structure having a bearing. The shaft support device only needs to have the following structure: it includes a shaft and a pair of support mechanisms provided at both axial ends of the shaft for supporting the shaft, and one of the pair of support mechanisms has a support body (for example, the support table 43 in the above-described embodiment) through which the shaft passes or is arranged around the shaft.

[0158] Therefore, as a support mechanism position adjustment mechanism for a shaft support device, it only needs to have the following structure: a first component (for example, the support table side component 61 in the above-described embodiment), which is provided on one of the shaft side and the support body side and can be penetrated by the shaft or arranged around the shaft; a second component (for example, the bearing housing side component 62 in the above-described embodiment), which is provided on the other of the shaft side and the support body side and can be penetrated by the shaft or arranged around the shaft and can move relative to the first component in the axial direction; an elastic component, which is arranged in a compressed state between the opposed axial end faces of the first component and the second component; and a damping component, which is arranged between the opposed faces of the first component and the second component.

[0159] Such a support mechanism position adjustment mechanism for a shaft support device can apply the structure of the housing position adjustment mechanism described in the ball screw feed device 20 and achieve the same effect.

[0160] For example, Figure 21 and Figure 22A rigid joint structure 200 as a shaft support device in which a support mechanism position adjustment mechanism is provided in one of a pair of support mechanisms that support a shaft. The rigid joint structure 200 includes two steel support bodies 231 and 243 that are vertically erected and fixed with respect to the base 1 and are parallel to each other. Concentric through holes 231a and 243a are formed in the support bodies 231 and 243, and a shaft 221 that constitutes a beam member is inserted therethrough. In addition, the support bodies 231 and 243 may be columns, beams, support plates, etc., as long as they are composed of members of any material and shape that can support the shaft.

[0161] It should be noted that in this example, one end of the shaft 221 is positioned and fixed to the support body 231 by another support mechanism in which the flange portion 226 on the axial one end side of the shaft 221 abuts against the small-diameter stepped portion 231b of the through hole 231a of the support body 231 and a gland 232 is installed on the large-diameter stepped portion 231c of the through hole 231a.

[0162] In addition, the other axial end portion of the shaft 221 is inserted through the through hole 243a of the support body 243, protrudes to the side opposite to the support body 231, and is supported by the support body 243 via a shaft guide member 250, a housing 251, and a support mechanism position adjustment mechanism 260 that constitute one support mechanism.

[0163] The cross-sectional shape of the central portion of the shaft 221 is arbitrary and may be composed of a square steel pipe, an H-shaped steel, etc.

[0164] The shaft guide member 250 is a member configured to surround the shaft 221, guides the small-diameter portion 225 of the shaft 221, and both outer diameter ends thereof are clamped and integrated by the housing 251 and a pressing member 247 fixed to the housing 251.

[0165] In addition, similar to the above-described embodiment, the housing 251 is installed on the support body 243 via the support mechanism position adjustment mechanism 260. That is, a first member 261 corresponding to the support base side member 61 in the above-described embodiment is fitted into the through hole 243a of the support body 243 and fixed to the support body 243, and a second member 262 corresponding to the bearing housing side member 62 in the above-described embodiment is fitted into the inward flange 251a of the housing 251 and fixed to the housing 251.

[0166] Therefore, when the shaft guide member 250 is fastened by a fastening nut 38b screwed onto the external thread 225a via a spacer 48, a reaction force acts on the shaft guide member 250 to cause the shaft guide member 250 to bear an axial load. Therefore, a predetermined rigidity is imparted between the support bodies 231 and 243 and the shaft 221.

[0167] In addition, in such a rigid joint structure 200, even if axial elongation occurs in the shaft 221, the support mechanism position adjustment mechanism 260 functions to follow the axial elongation of the shaft 221 and move the shaft guide member 250 and the housing 251 in the same direction. Therefore, the axial force acting on the shaft 221 can be maintained, and the rigidity of the rigid joint structure 200 can be retained.

[0168] In addition, in this example, the housing 251 and the second member 262 of the support mechanism position adjustment mechanism 260 may be integrally formed, and the shaft guide member 250 may be arranged on the integrated member. Alternatively, the housing 251 may not be provided, and the shaft guide member 250 may be directly fixed to the second member 262 of the support mechanism position adjustment mechanism 260.

[0169] In addition, the shaft support device is not limited to the rigid joint structure as in this embodiment, and may be a support structure in which the support mechanisms on the shaft side and the support body side are pin-connected. In this case, the shaft 221 may also be arranged obliquely according to the structure of the support structure.

[0170] Moreover, in a shaft support device such as a rigid body structure, it is also possible that both support mechanisms have a structure with a support mechanism position adjustment mechanism.

[0171] As described above, the following matters are disclosed in this specification.

[0172] (A1) A ball screw feed device includes: a screw shaft having a spiral thread groove formed on its outer peripheral surface; a nut having a spiral thread groove formed on its inner peripheral surface; a plurality of balls rotatably disposed between the thread groove of the screw shaft and the thread groove of the nut; and a pair of support mechanisms respectively rotatably supporting the axial end portions of the screw shaft.

[0173] One of the pair of support mechanisms includes:

[0174] a bearing unit including a bearing housing; and an angular contact ball bearing respectively including an outer ring embedded in the bearing housing, an inner ring externally fitted to the axial end portion of the screw shaft, and balls rotatably disposed between the outer ring and the inner ring;

[0175] a support table disposed at a position axially closer to the center than the bearing unit and penetrated by the screw shaft; and

[0176] a housing position adjustment mechanism disposed between the bearing unit and the support table,

[0177] The housing position adjustment mechanism includes:

[0178] a support table side member provided on the support table side and penetrated by the screw shaft;

[0179] A bearing housing side member, which is provided on the bearing housing side, penetrated by the lead screw shaft, and capable of relative axial movement with respect to the support table side member;

[0180] An elastic member, which is arranged in a compressed state between the opposed axial end faces of the support table side member and the bearing housing side member; and

[0181] A damping member, which is arranged between the opposed surfaces of the support table side member and the bearing housing side member.

[0182] According to this structure, even if the axial length of the lead screw shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0183] (A2) The ball screw feed device according to (A1), wherein,

[0184] One of the support table side member and the bearing housing side member has an annular recess opening to one side in the axial direction,

[0185] The other of the support table side member and the bearing housing side member has an annular protrusion protruding toward the other side in the axial direction and fitting into the annular recess in a slidable manner along the axial direction,

[0186] The elastic member is a plurality of disc springs arranged in a compressed state between the bottom surface of the annular recess and the top surface of the annular protrusion.

[0187] According to this structure, a plurality of disc springs can be arranged in a compressed state in the space (pressure chamber in this embodiment) formed between the annular recess and the annular protrusion, the wear powder generated by the disc springs can be prevented from flowing out to the outside, foreign matters can be prevented from invading from the outside, and a housing position adjustment mechanism having disc springs and a damping member can be compactly formed around the lead screw shaft.

[0188] (A3) The ball screw feed device according to (A2), wherein,

[0189] The damping member is at least one O-ring respectively assembled between the inner-facing surface of the annular recess and the outer-facing surface of the annular protrusion, and between the outer-facing surface of the annular recess and the inner-facing surface of the annular protrusion.

[0190] According to this structure, the vibration generated in the lead screw shaft can be attenuated by the O-ring.

[0191] (A4) The ball screw feed device according to (A1), wherein,

[0192] One of the support table side member and the bearing housing side member has: a small-diameter cylindrical portion extending axially in one direction; and an outward flange portion extending radially outward from the tip of the small-diameter cylindrical portion.

[0193] The other of the support table side member and the bearing housing side member has: a large-diameter cylindrical portion extending axially in the other direction, having an inner peripheral surface for slidably contacting the outer peripheral surface of the outward flange portion; and an inward flange portion extending radially inward from the tip of the large-diameter cylindrical portion and having an inner peripheral surface for slidably contacting the outer peripheral surface of the small-diameter cylindrical portion.

[0194] The elastic members are a plurality of disc springs arranged in a compressed state in an annular space defined by the small-diameter cylindrical portion, the outward flange portion, the large-diameter cylindrical portion, and the inward flange portion.

[0195] According to this structure, a plurality of disc springs can be arranged in a compressed state in the annular space, preventing wear powder generated by the disc springs from flowing out to the outside and foreign matter from invading from the outside, and also enabling a compact configuration of a housing position adjustment mechanism having disc springs and damping members around the lead screw shaft.

[0196] (A5) The ball screw feed device according to (A4), wherein

[0197] The damping members are at least one O-ring respectively assembled between the inner peripheral surface of the inward flange portion and the outer peripheral surface of the small-diameter cylindrical portion, and between the outer peripheral surface of the outward flange portion and the inner peripheral surface of the large-diameter cylindrical portion.

[0198] According to this structure, the O-ring functions as a damping mechanism, capable of damping vibrations generated in the lead screw shaft.

[0199] (A6) The ball screw feed device according to (A1), wherein

[0200] One of the pair of support mechanisms further includes another housing position adjustment mechanism, which is arranged in series or in parallel adjacent to the housing position adjustment mechanism between the bearing unit and the support table.

[0201] The another housing position adjustment mechanism includes:

[0202] Another support table side member, which is arranged on the support table side and penetrated by the lead screw shaft;

[0203] Another bearing housing side member, which is arranged on the bearing housing side, penetrated by the lead screw shaft, and capable of relatively moving axially with respect to the another support table side member; and

[0204] A pressure generating unit disposed in a compressed state between the opposing axial end faces of the other support table side member and the other bearing housing side member.

[0205] According to this structure, in the case of series configuration, even when the elongation of the lead screw shaft is greater, the axial rigidity of the ball screw feed device can be maintained. In addition, the centering and coaxiality of the lead screw shaft can be improved. Further, in the case of parallel configuration, an axial load greater than that when a separate housing position adjustment mechanism is arranged is generated, and the axial rigidity can be maintained.

[0206] (A7) A ball screw feed device comprising: a lead screw shaft having a helical thread groove formed on its outer peripheral surface; a nut having a helical thread groove formed on its inner peripheral surface; a plurality of balls rollably disposed between the thread groove of the lead screw shaft and the thread groove of the nut; and a pair of support mechanisms respectively rotatably supporting the axial end portions of the lead screw shaft.

[0207] One of the pair of support mechanisms includes:

[0208] A bearing unit having a bearing housing and an angular contact ball bearing, the angular contact ball bearing respectively having an outer ring embedded in the bearing housing, an inner ring externally fitted to the axial end portion of the lead screw shaft, and balls rollably disposed between the outer ring and the inner ring;

[0209] A support table penetrated by the lead screw shaft; and

[0210] A housing position adjustment mechanism mounted on the bearing unit and the support table,

[0211] The housing position adjustment mechanism includes:

[0212] A support table side member mounted on the support table and penetrated by the lead screw shaft;

[0213] A bearing housing side member mounted on the bearing housing and penetrated by the lead screw shaft and capable of relatively moving axially with respect to the support table side member;

[0214] An elastic member disposed in a compressed state between the opposing axial end faces of the support table side member and the bearing housing side member; and

[0215] A damping member disposed between the opposing surfaces of the support table side member and the bearing housing side member.

[0216] According to this structure, even when the axial length of the lead screw shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0217] (A8)A rotary support device, comprising:

[0218] A rotary shaft; and a pair of support mechanisms that respectively support both axial ends of the rotary shaft rotatably.

[0219] One of the pair of support mechanisms includes:

[0220] A bearing unit that includes a bearing housing and a bearing, and can support the rotary shaft rotatably relative to the bearing housing and can support an axial load.

[0221] A support table disposed at a position axially closer to the center than the bearing unit and penetrated by the rotary shaft; and

[0222] A housing position adjustment mechanism disposed between the bearing unit and the support table.

[0223] The housing position adjustment mechanism includes:

[0224] A support table side member disposed on the support table side and penetrated by the rotary shaft;

[0225] A bearing housing side member disposed on the bearing housing side, penetrated by the rotary shaft, and capable of moving axially relative to the support table side member;

[0226] An elastic member disposed in a compressed state between opposing axial end faces of the support table side member and the bearing housing side member; and

[0227] A damping member disposed between opposing surfaces of the support table side member and the bearing housing side member.

[0228] According to this structure, even if the axial length of the rotary shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and axial vibration can be attenuated.

[0229] (A9)A rotary support device, comprising:

[0230] A rotary shaft; and a pair of support mechanisms that respectively support both axial ends of the rotary shaft rotatably.

[0231] One of the pair of support mechanisms has:

[0232] A bearing unit that has a bearing housing and a bearing, and the bearing supports the rotary shaft rotatably relative to the bearing housing and can support an axial load.

[0233] A support table penetrated by the rotary shaft; and

[0234] A housing position adjustment mechanism is installed on the bearing unit and the support table.

[0235] The housing position adjustment mechanism includes:

[0236] A support table side member is installed on the support table and penetrated by the rotating shaft.

[0237] A bearing housing side member is installed on the bearing housing, penetrated by the rotating shaft, and capable of relatively moving axially with respect to the support table side member.

[0238] An elastic member is disposed in a compressed state between the opposing axial end faces of the support table side member and the bearing housing side member; and

[0239] A damping member is disposed between the opposing surfaces of the support table side member and the bearing housing side member.

[0240] According to this structure, even if the axial length of the rotating shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0241] (A10) A support mechanism position adjustment mechanism of a shaft support device is provided in one of a pair of support mechanisms in the shaft support device. The shaft support device includes a shaft and a pair of support mechanisms provided at both axial ends of the shaft for supporting the shaft on a base.

[0242] The support mechanism position adjustment mechanism of the shaft support device includes:

[0243] A first member is provided on one of the support mechanism side and the base side and can be penetrated by the shaft.

[0244] A second member is provided on the other of the support mechanism side and the base side, can be penetrated by the shaft, and can relatively move axially with respect to the first member.

[0245] An elastic member is disposed in a compressed state between the opposing axial end faces of the first member and the second member; and

[0246] A damping member is disposed between the opposing surfaces of the first member and the second member.

[0247] According to this structure, even if the axial length of the shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0248] (A11) A support mechanism position adjustment mechanism for a shaft support device, which is provided in one of a pair of support mechanisms in the shaft support device. The shaft support device includes a shaft and a pair of support mechanisms provided at both axial ends of the shaft for supporting the shaft on a base.

[0249] The support mechanism position adjustment mechanism of the shaft support device includes:

[0250] A first component, which is installed on one of the support mechanism and the base and can be penetrated by the shaft;

[0251] A second component, which is installed on the other of the support mechanism and the base, can be penetrated by the shaft, and can move relative to the first component axially;

[0252] An elastic component, which is arranged in a compressed state between the opposing axial end faces of the first component and the second component; and

[0253] A damping component, which is arranged between the opposing surfaces of the first component and the second component.

[0254] According to this structure, even if the axial length of the shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0255] (A12) A rotary support device, including:

[0256] A rotating shaft; and a pair of support mechanisms, which respectively support both axial ends of the rotating shaft rotatably,

[0257] One of the pair of support mechanisms includes:

[0258] A bearing unit, which includes a bearing housing and a bearing. The bearing can support the rotating shaft rotatably relative to the bearing housing and can support an axial load;

[0259] A support table, which is penetrated by the rotating shaft; and

[0260] A housing position adjustment mechanism, which is arranged between the bearing unit and the support table,

[0261] The housing position adjustment mechanism includes:

[0262] A support table side component, which is arranged on the support table side and is penetrated by the rotating shaft or arranged around the rotating shaft;

[0263] A bearing housing side component, which is arranged on the bearing housing side and is penetrated by the rotating shaft or arranged around the rotating shaft, and can move relative to the support table side component axially;

[0264] An elastic member disposed in a compressed state between opposing axial end faces of the support base side member and the bearing housing side member; and

[0265] A damping member disposed between opposing surfaces of the support base side member and the bearing housing side member.

[0266] According to this structure, even if the axial length of the rotating shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and axial vibration can be attenuated.

[0267] (A13) The rotary support device according to (A12), wherein

[0268] One of the support base side member and the bearing housing side member has a plurality of recesses opening axially to one side,

[0269] The other of the support base side member and the bearing housing side member has a plurality of protrusions that project axially to the other side and are respectively fitted into the plurality of recesses in a slidable manner along the axis,

[0270] A plurality of the pressure chambers are respectively formed between the plurality of recesses and the plurality of protrusions.

[0271] According to this structure, the layout of the housing position adjustment mechanism can be freely constituted by a plurality of pressure chambers.

[0272] (A14) The rotary support device according to (A13), wherein

[0273] The plurality of pressure chambers are disposed on both sides in the width direction with respect to the rotating shaft.

[0274] According to this structure, the height dimension of the housing position adjustment mechanism can be suppressed.

[0275] (A15) The rotary support device according to (A13), wherein

[0276] The elastic members are respectively disposed in the plurality of pressure chambers,

[0277] The damping members are respectively disposed between opposing surfaces of the plurality of protrusions and the plurality of recesses.

[0278] According to this structure, a plurality of pressure chambers can be commonly constituted.

[0279] (A16) The rotary support device according to (A12), wherein

[0280] The rotary support device is a ball screw feed device,

[0281] The ball screw feed device has a lead screw shaft with a helical thread groove formed on its outer peripheral surface, and further includes: a nut with a helical thread groove formed on its inner peripheral surface; and a plurality of balls rotatably disposed between the thread groove of the lead screw shaft and the thread groove of the nut.

[0282] According to this structure, a ball screw feed device can be constituted that can continuously and stably maintain the axial support rigidity even when the axial length of the rotating shaft changes due to the influence of heat.

[0283] (A17) A support mechanism position adjustment mechanism of a shaft support device, which is provided in one of a pair of support mechanisms in the shaft support device. The shaft support device includes a shaft and a pair of support mechanisms provided at both axial ends of the shaft to support the shaft on a base.

[0284] The support mechanism position adjustment mechanism of the shaft support device includes:

[0285] A first component provided on one of the support mechanism side and the base side, which can be penetrated by the shaft or can be arranged around the shaft;

[0286] A second component provided on the other of the support mechanism side and the base side, which can be penetrated by the shaft or can be arranged around the shaft and can move relatively axially with respect to the first component;

[0287] An elastic component arranged in a compressed state between the opposing axial end faces of the first component and the second component; and

[0288] A damping component arranged between the opposing surfaces of the first component and the second component.

[0289] According to this structure, even when the axial length of the shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0290] (B1) A rotary support device includes:

[0291] A rotating shaft; and a pair of support mechanisms that respectively support both axial ends of the rotating shaft rotatably,

[0292] One of the pair of support mechanisms includes:

[0293] A bearing unit including a bearing housing and a bearing that can support the rotating shaft rotatably with respect to the bearing housing and can support an axial load;

[0294] A support table that is penetrated by the rotating shaft or disposed around the rotating shaft; and

[0295] A housing position adjustment mechanism disposed between the bearing unit and the support table,

[0296] The housing position adjustment mechanism includes:

[0297] A support table side member disposed on the support table side, penetrated by the rotating shaft or disposed around the rotating shaft;

[0298] A bearing housing side member disposed on the bearing housing side, penetrated by the rotating shaft or disposed around the rotating shaft, and capable of relatively moving axially with respect to the support table side member;

[0299] An elastic member disposed in a compressed state between the opposing axial end faces of the support table side member and the bearing housing side member; and

[0300] A damping member disposed between the opposing surfaces of the support table side member and the bearing housing side member.

[0301] According to this structure, even if the axial length of the rotating shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0302] (B2) The rotary support device according to (B1), wherein

[0303] One of the support table side member and the bearing housing side member has an annular recess that opens to one side in the axial direction,

[0304] The other of the support table side member and the bearing housing side member has an annular protrusion that protrudes toward the other side in the axial direction and is fitted into the annular recess in a slidable manner along the axial direction,

[0305] The elastic member is a plurality of disc springs disposed in a compressed state between the bottom surface of the annular recess and the top surface of the annular protrusion.

[0306] According to this structure, a plurality of disc springs can be disposed in a compressed state in the space (pressure chamber in this embodiment) formed between the annular recess and the annular protrusion, preventing the wear powder generated by the disc springs from flowing out to the outside and foreign matters from invading from the outside, and also enabling the housing position adjustment mechanism having the disc springs and the damping member to be compactly formed around the rotating shaft.

[0307] (B3) The rotary support device according to (B2), wherein

[0308] The damping member is at least one O-ring respectively assembled between the inner-facing surface of the annular recess and the outer-facing surface of the annular protrusion, and between the outer-facing surface of the annular recess and the inner-facing surface of the annular protrusion.

[0309] According to this structure, vibration generated on the rotating shaft can be damped by the O-ring.

[0310] (B4) The rotary support device according to (B1), wherein

[0311] One of the support base side member and the bearing housing side member has: a small-diameter cylindrical portion extending axially in one direction; and an outward flange portion extending radially outward from the tip of the small-diameter cylindrical portion.

[0312] The other of the support base side member and the bearing housing side member has: a large-diameter cylindrical portion extending axially in the other direction and having an inner peripheral surface for slidably contacting the outer peripheral surface of the outward flange portion; and an inward flange portion extending radially inward from the tip of the large-diameter cylindrical portion and having an inner peripheral surface for slidably contacting the outer peripheral surface of the small-diameter cylindrical portion.

[0313] The elastic member is a plurality of disc springs arranged in a compressed state in the annular space separated by the small-diameter cylindrical portion, the outward flange portion, the large-diameter cylindrical portion, and the inward flange portion.

[0314] According to this structure, a plurality of disc springs can be arranged in a compressed state in the annular space, preventing wear powder generated by the disc springs from flowing out to the outside and foreign matters from invading from the outside, and also enabling a compact configuration of a housing position adjustment mechanism having disc springs and damping members around the rotating shaft.

[0315] (B5) The rotary support device according to (B4), wherein

[0316] The damping member is at least one O-ring respectively assembled between the inner peripheral surface of the inward flange portion and the outer peripheral surface of the small-diameter cylindrical portion, and between the outer peripheral surface of the outward flange portion and the inner peripheral surface of the large-diameter cylindrical portion.

[0317] According to this structure, the O-ring functions as a damping mechanism and can damp vibration generated on the rotating shaft.

[0318] (B6) The rotary support device according to (B1), wherein

[0319] One of the pair of support mechanisms further includes another housing position adjustment mechanism, which is arranged in series or in parallel adjacent to the housing position adjustment mechanism between the bearing unit and the support base.

[0320] The other housing position adjustment mechanism includes:

[0321] Another support table side member, which is disposed on the support table side and is penetrated by the rotating shaft or disposed around the rotating shaft;

[0322] Another bearing housing side member, which is disposed on the bearing housing side and is penetrated by the rotating shaft or disposed around the rotating shaft, and can move relative to the other support table side member in the axial direction; and

[0323] A pressure generating unit, which is disposed in a compressed state between the opposing axial end faces of the other support table side member and the other bearing housing side member.

[0324] According to this structure, in the case of series configuration, even when the elongation of the rotating shaft is greater, the axial rigidity of the rotary bearing device can be maintained. In addition, the centering and coaxiality of the rotating shaft can be improved. Further, in the case of parallel configuration, an axial load larger than that when a single housing position adjustment mechanism is disposed can be generated, and the axial rigidity can be maintained.

[0325] (B7) The rotary bearing device according to (B1), wherein

[0326] One of the support table side member and the bearing housing side member has a plurality of recesses opening to one side in the axial direction,

[0327] The other of the support table side member and the bearing housing side member has a plurality of protrusions, and the plurality of protrusions protrude toward the other side in the axial direction and are respectively fitted into the plurality of recesses in a slidable manner along the axial direction,

[0328] A plurality of the pressure chambers are respectively formed between the plurality of recesses and the plurality of protrusions.

[0329] According to this structure, the layout of the housing position adjustment mechanism can be freely formed by the plurality of pressure chambers.

[0330] (B8) The rotary bearing device according to (B7), wherein

[0331] The plurality of pressure chambers are disposed on both sides in the width direction with respect to the rotating shaft.

[0332] According to this structure, the height dimension of the housing position adjustment mechanism can be suppressed.

[0333] (B9) The rotary bearing device according to (B7), wherein

[0334] The elastic members are respectively disposed in the plurality of pressure chambers,

[0335] The attenuation members are respectively disposed between the opposing surfaces of the plurality of convex portions and the plurality of concave portions.

[0336] According to this structure, a plurality of pressure chambers can be commonly formed.

[0337] (B10) The rotary support device according to any one of (B1) to (B9), wherein

[0338] The bearing of the bearing unit includes a pair of angular contact ball bearings, and each of the pair of angular contact ball bearings includes: an outer ring embedded in the bearing housing, an inner ring fitted onto the axial end of the rotating shaft, and balls rotatably disposed between the outer ring and the inner ring.

[0339] According to this structure, even if the axial length of the rotating shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0340] (B11) The rotary support device according to any one of (B1) to (B10), wherein

[0341] The rotary support device is a ball screw feed device,

[0342] The ball screw feed device has a lead screw shaft with a helical thread groove formed on its outer peripheral surface, and further includes: a nut with a helical thread groove formed on its inner peripheral surface; and a plurality of balls rotatably disposed between the thread groove of the lead screw shaft and the thread groove of the nut.

[0343] According to this structure, a ball screw feed device can be formed that can continuously and stably maintain the axial support rigidity even if the axial length of the rotating shaft changes due to the influence of heat.

[0344] (B12) A support mechanism position adjustment mechanism of a shaft support device, which is provided on one of a pair of support mechanisms in the shaft support device, the shaft support device having a shaft and a pair of support mechanisms provided at both axial ends of the shaft for supporting the shaft,

[0345] One of the pair of support mechanisms has a support body penetrated by the shaft or disposed around the shaft,

[0346] The support mechanism position adjustment mechanism of the shaft support device includes:

[0347] A first member, which is provided on one of the shaft side and the support body side and can be penetrated by the shaft or disposed around the shaft;

[0348] A second component, which is disposed on the other one of the shaft side and the support body side, can be penetrated by the shaft or disposed around the shaft, and can relatively move axially with respect to the first component;

[0349] An elastic component, which is disposed in a compressed state between the opposing axial end faces of the first component and the second component; and

[0350] A damping component, which is disposed between the opposing surfaces of the first component and the second component.

[0351] According to this structure, even if the axial length of the shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0352] (B13) The support mechanism position adjustment mechanism of the shaft support device according to (B12), wherein,

[0353] The shaft is a rotating shaft,

[0354] One of the pair of support mechanisms further includes a bearing unit, and the bearing unit includes a bearing housing and a bearing. The bearing supports the rotating shaft to be rotatable relative to the bearing housing and the bearing can support an axial load,

[0355] The support mechanism position adjustment mechanism is a housing position adjustment mechanism disposed between the bearing unit and the support body,

[0356] The first component is a support body side component, and the support body side component is disposed on the support body side, can be penetrated by the rotating shaft, or can be disposed around the rotating shaft,

[0357] The second component is a bearing housing side component, and the bearing housing side component is disposed on the bearing housing side, can be penetrated by the rotating shaft, or can be disposed around the rotating shaft, and can relatively move axially with respect to the support body side component,

[0358] According to this structure, even if the axial length of the rotating shaft changes due to the influence of heat, the axial support rigidity can be continuously and stably maintained, and the axial vibration can be attenuated.

[0359] (B14) The support mechanism position adjustment mechanism of the shaft support device according to (B12) or (B13), wherein,

[0360] One of the first component and the second component has an annular recess opening on one axial side,

[0361] The other of the first component and the second component has an annular convex portion that protrudes toward the other axial side and is fitted into the annular concave portion in a slidable manner along the axial direction.

[0362] The elastic member is a plurality of disc springs arranged in a compressed state between the bottom surface of the annular concave portion and the top surface of the annular convex portion.

[0363] According to this structure, a plurality of disc springs can be arranged in a compressed state in the space (pressure chamber in this embodiment) formed between the annular concave portion and the annular convex portion, preventing the wear powder generated by the disc springs from flowing out to the outside and foreign matters from invading from the outside. Also, a support mechanism position adjustment mechanism having disc springs and damping members can be compactly formed around the shaft.

[0364] (B15) The support mechanism position adjustment mechanism of the shaft support device according to (B14), wherein

[0365] The damping member is at least one O-ring respectively assembled between the inner-facing surface of the annular concave portion and the outer-facing surface of the annular convex portion, and between the outer-facing surface of the annular concave portion and the inner-facing surface of the annular convex portion.

[0366] According to this structure, the vibration generated in the shaft can be attenuated by the O-ring.

[0367] (B16) The support mechanism position adjustment mechanism of the shaft support device according to (B12) or (B13), wherein

[0368] One of the first component and the second component has: a small-diameter cylindrical portion extending toward one axial side; and an outward flange portion extending from the top end portion of the small-diameter cylindrical portion toward the outer diameter side.

[0369] The other of the first component and the second component has: a large-diameter cylindrical portion extending toward the other axial side, having an inner peripheral surface for the outer peripheral surface of the outward flange portion to slide in contact with; and an inward flange portion extending from the top end portion of the large-diameter cylindrical portion toward the inner diameter side, having an inner peripheral surface that slides in contact with the outer peripheral surface of the small-diameter cylindrical portion.

[0370] The elastic member is a plurality of disc springs arranged in a compressed state in the annular space separated by the small-diameter cylindrical portion, the outward flange portion, the large-diameter cylindrical portion, and the inward flange portion.

[0371] According to this structure, a plurality of disc springs can be arranged in a compressed state in the annular space, preventing the wear powder generated by the disc springs from flowing out to the outside and foreign matters from invading from the outside. Also, a support mechanism position adjustment mechanism having disc springs and damping members can be compactly formed around the shaft.

[0372] (B17) The support mechanism position adjustment mechanism of the shaft support device according to (B16), wherein,

[0373] The damping member is at least one O-ring respectively assembled between the inner peripheral surface of the inward flange portion and the outer peripheral surface of the small-diameter cylindrical portion, and between the outer peripheral surface of the outward flange portion and the inner peripheral surface of the large-diameter cylindrical portion.

[0374] According to this structure, the O-ring functions as a damping mechanism and can attenuate the vibration generated in the shaft.

[0375] (B18) The support mechanism position adjustment mechanism of the shaft support device according to (B12) or (B13), wherein,

[0376] One of the pair of support mechanisms further includes another support mechanism position adjustment mechanism, and this another support mechanism position adjustment mechanism is arranged in series or in parallel adjacent to the support mechanism position adjustment mechanism between the bearing unit and the support table.

[0377] The another support mechanism position adjustment mechanism includes:

[0378] Another first component, which is arranged on the support table side and is penetrated by the shaft or arranged around the shaft;

[0379] Another second component, which is arranged on the bearing housing side and is penetrated by the shaft or arranged around the shaft and can move axially relative to the another first component; and

[0380] A pressure generating unit, which is arranged in a compressed state between the opposing axial end faces of the another first component and the another second component.

[0381] According to this structure, in the case of series arrangement, even when the elongation of the shaft is greater, the axial rigidity of the shaft support device can be maintained. In addition, the centering property and coaxiality of the shaft can be improved. Further, in the case of parallel arrangement, an axial load larger than that when a single support mechanism position adjustment mechanism is arranged can be generated, and the axial rigidity can be maintained.

[0382] (B19) The rotary support device according to (B12) or (B13), wherein,

[0383] One of the first component and the second component has a plurality of recesses opening to one side in the axial direction.

[0384] The other of the first component and the second component has a plurality of protrusions, and the plurality of protrusions protrude toward the other side in the axial direction and are respectively fitted into the plurality of recesses in a slidable manner along the axial direction.

[0385] A plurality of the pressure chambers are respectively formed between a plurality of the concave portions and a plurality of the convex portions.

[0386] According to this structure, the layout of the support mechanism position adjustment mechanism can be freely configured by a plurality of pressure chambers.

[0387] (B20) The rotary support device according to (B19), wherein

[0388] A plurality of the pressure chambers are arranged on both sides in the width direction with respect to the shaft.

[0389] According to this structure, the height dimension of the support mechanism position adjustment mechanism can be suppressed.

[0390] (B21) The rotary support device according to (B19), wherein

[0391] The elastic members are respectively arranged in a plurality of the pressure chambers,

[0392] The damping members are respectively arranged between the opposing surfaces of a plurality of the convex portions and a plurality of the concave portions.

[0393] According to this structure, a plurality of pressure chambers can be commonly configured.

[0394] In addition, this application is based on Japanese Patent Application (Japanese Patent Application No. 2022-173760) filed on October 28, 2022, Japanese Patent Application (Japanese Patent Application No. 2023-118994) filed on July 21, 2023, and Japanese Patent Application (Japanese Patent Application No. 2023-134634) filed on August 22, 2023, the contents of which are incorporated herein by reference.

[0395] Explanation of reference numerals

[0396] 20 Ball screw feed device (shaft support device, rotary support device)

[0397] 21 Lead screw shaft (shaft, rotary shaft)

[0398] 21b Thread groove

[0399] 23 Nut

[0400] 30 First support mechanism (support mechanism)

[0401] 31 Fixed-side bearing housing

[0402] 33, 53 Angular contact ball bearings (bearings)

[0403] 34, 54 Outer rings

[0404] Inner rings 35 and 55

[0405] Balls 36 and 56

[0406] Lock nuts 38a and 38b

[0407] Second support mechanism (support mechanism) 40

[0408] Bearing unit 41

[0409] Support table (support body) 43

[0410] Moving side bearing housing (bearing housing) 51

[0411] Inward flange 51a

[0412] Housing position adjustment mechanism (support mechanism position adjustment mechanism) 60

[0413] Support table side component (first component) 61

[0414] Bearing housing side component (second component) 62

[0415] Annular recess 64

[0416] Annular protrusion 65

[0417] Pressure chamber 66

[0418] O-ring (attenuation component) 67

[0419] Seal groove 68

[0420] Disc spring (elastic component) 70

[0421] Rotary support device 120

[0422] Rotating shaft 121

[0423] Another housing position adjustment mechanism (another support mechanism position adjustment mechanism) 160

[0424] Another support table side component 161

[0425] Another bearing housing side component

Claims

1. A rotary bearing device, characterized in that, it comprises: a rotary shaft; and a pair of support mechanisms, and the pair of support mechanisms respectively support both axial end portions of the rotary shaft so as to be rotatable freely, one of the pair of support mechanisms comprises: a bearing unit, the bearing unit comprising a bearing housing and a bearing, the bearing supporting the rotary shaft relative to the bearing housing so as to be rotatable freely, and the bearing being capable of supporting an axial load; a support table, the support table being penetrated by the rotary shaft or disposed around the rotary shaft; and a housing position adjustment mechanism, the housing position adjustment mechanism being disposed between the bearing unit and the support table, the housing position adjustment mechanism comprises: a support table side member, the support table side member being disposed on the support table side and being penetrated by the rotary shaft or disposed around the rotary shaft; a bearing housing side member, the bearing housing side member being disposed on the bearing housing side and being penetrated by the rotary shaft or disposed around the rotary shaft, and being capable of relatively moving axially with respect to the support table side member; an elastic member, the elastic member being disposed in a compressed state between the opposing axial end faces of the support table side member and the bearing housing side member; and a damping member, the damping member being disposed between the opposing surfaces of the support table side member and the bearing housing side member.

2. The rotary bearing device according to claim 1, characterized in that, one of the support table side member and the bearing housing side member has an annular recess opening axially to one side, the other of the support table side member and the bearing housing side member has an annular protrusion, the annular protrusion protruding axially to the other side and being fitted in the annular recess in a manner capable of sliding axially, the elastic member is a plurality of disc springs disposed in a compressed state between the bottom surface of the annular recess and the top surface of the annular protrusion.

3. The rotary bearing device according to claim 2, characterized in that, the damping member is at least one O-ring respectively assembled between the inner facing surface of the annular recess and the outer facing surface of the annular protrusion, and between the outer facing surface of the annular recess and the inner facing surface of the annular protrusion.

4. The rotary bearing device according to claim 1, characterized in that, one of the support table side member and the bearing housing side member has: a small-diameter cylindrical portion extending axially to one side; and an outward flange portion extending radially outward from the tip of the small-diameter cylindrical portion, the other of the support table side member and the bearing housing side member has: a large-diameter cylindrical portion extending axially to the other side, having an inner peripheral surface for the outer peripheral surface of the outward flange portion to slide in contact with; and an inward flange portion extending radially inward from the tip of the large-diameter cylindrical portion, having an inner peripheral surface for the outer peripheral surface of the small-diameter cylindrical portion to slide in contact with, The elastic members are a plurality of disc springs arranged in a compressed state in an annular space defined by the small-diameter cylindrical portion, the outward flange portion, the large-diameter cylindrical portion, and the inward flange portion.

5. The rotary support device according to claim 4, wherein, the damping members are at least one O-ring respectively assembled between the inner peripheral surface of the inward flange portion and the outer peripheral surface of the small-diameter cylindrical portion, and between the outer peripheral surface of the outward flange portion and the inner peripheral surface of the large-diameter cylindrical portion.

6. The rotary support device according to claim 1, wherein, one of the pair of support mechanisms further includes another housing position adjustment mechanism, and the another housing position adjustment mechanism is arranged in series or in parallel adjacent to the housing position adjustment mechanism between the bearing unit and the support base, the another housing position adjustment mechanism includes: another support base side member, the another support base side member is arranged on the support base side, penetrated by the rotary shaft or arranged around the rotary shaft; another bearing housing side member, the another bearing housing side member is arranged on the bearing housing side, penetrated by the rotary shaft or arranged around the rotary shaft, and capable of relatively moving axially with respect to the another support base side member; and a pressure generating unit, the pressure generating unit is arranged in a compressed state between the opposing axial end faces of the another support base side member and the another bearing housing side member.

7. The rotary support device according to claim 1, wherein, one of the support base side member and the bearing housing side member has a plurality of recesses opening axially to one side, the other of the support base side member and the bearing housing side member has a plurality of protrusions, and the plurality of protrusions protrude axially to the other side and are respectively fitted into the plurality of recesses in a slidable manner along the axial direction, a plurality of the pressure chambers are respectively formed between the plurality of recesses and the plurality of protrusions.

8. The rotary support device according to claim 7, wherein, the plurality of pressure chambers are arranged on both sides in the width direction with respect to the rotary shaft.

9. The rotary support device according to claim 7, wherein, the elastic members are respectively arranged in the plurality of pressure chambers, the damping members are respectively arranged between the opposing surfaces of the plurality of protrusions and the plurality of recesses.

10. The rotary support device according to claim 1, wherein, the bearing of the bearing unit includes a pair of angular contact ball bearings, and each of the pair of angular contact ball bearings includes: an outer ring embedded in the bearing housing, an inner ring externally fitted to the axial end of the rotary shaft, and balls arranged between the outer ring and the inner ring so as to be freely rotatable.

11. The rotary support device according to claim 1, wherein, the rotary support device is a ball screw feed device, The ball screw feed device has a lead screw shaft with a helical thread groove formed on its outer peripheral surface, and further includes: a nut having a helical thread groove formed on its inner peripheral surface; and a plurality of balls that are rotatably disposed between the thread groove of the lead screw shaft and the thread groove of the nut.

12. A support mechanism position adjustment mechanism for a shaft support device, characterized in that the support mechanism position adjustment mechanism of the shaft support device is provided in one of a pair of support mechanisms in the shaft support device, and the shaft support device includes a shaft and a pair of the support mechanisms provided at both axial ends of the shaft for supporting the shaft, one of the pair of support mechanisms has a support body that is penetrated by the shaft or disposed around the shaft, the support mechanism position adjustment mechanism of the shaft support device includes: a first member that is provided on one of the shaft side and the support body side and can be penetrated by the shaft or disposed around the shaft; a second member that is provided on the other of the shaft side and the support body side and can be penetrated by the shaft or disposed around the shaft and can move relative to the first member in the axial direction; an elastic member that is disposed in a compressed state between the opposing axial end faces of the first member and the second member; and a damping member that is disposed between the opposing surfaces of the first member and the second member.

13. The support mechanism position adjustment mechanism of the shaft support device according to claim 12, characterized in that the shaft is a rotating shaft, one of the pair of support mechanisms further includes a bearing unit having a bearing housing and a bearing that rotatably supports the rotating shaft relative to the bearing housing and can support an axial load, the support mechanism position adjustment mechanism is a housing position adjustment mechanism disposed between the bearing unit and the support body, the first member is a support body side member that is provided on the support body side and can be penetrated by the rotating shaft or disposed around the rotating shaft, the second member is a bearing housing side member that is provided on the bearing housing side and can be penetrated by the rotating shaft or disposed around the rotating shaft and can move relative to the support body side member in the axial direction.

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