Bearing arrangement

Abstract

A bearing device cools only an outer side gap (33) by an outer side gap cooling structure. Thus, a temperature difference is generated between an inner side gap (32) and the outer side gap (33). The inner ring (37) of the bearing (31) is relatively displaced with respect to the outer ring (38) in a direction in which pre-pressing of the inside of the bearing (31) is reduced in correspondence with the temperature difference.

Description

[0001] This application is a divisional application of the invention patent application filed on May 26, 2021, with application number 202110575280.9 and title "Bearing Device". Technical Field

[0002] The present invention relates to a bearing device that freely supports a rotating shaft, and more particularly to a bearing device well suited for supporting a large-diameter rotating shaft that rotates at high speed. Background Technology

[0003] In bearing assemblies that use bearings to support rotating shafts, the preload inside the bearings must be adjusted with high precision in order to ensure smooth rotation of the support.

[0004] However, due to the frictional heat generated inside the bearing associated with the rotation of the rotating shaft, as well as the temperature rise of the rotating shaft caused by external factors, the bearing and the rotating shaft expand in the radial direction (diameter direction), and the preload inside the bearing increases. As a result, there is a risk that the bearing will lock up and no longer be able to rotate smoothly.

[0005] Therefore, several cooling strategies for bearing devices have been proposed in the past.

[0006] For example, the cooling structure of the bearing device disclosed in Japanese Patent Application Publication No. 2019-173911 (patent document) is as follows: an air supply port (23) is provided on the inner circumferential surface of the outer ring seat (15) of the rolling bearing (3, 4), and compressed air (A) for cooling is sprayed from the air supply port (23) toward the outer circumferential surface of the inner ring seat (16) to cool the outer ring seat (15) and the inner ring seat (16) respectively. The compressed air (A) is exhausted from the seat space (21A, 21B) through the exhaust path (30) formed inside the housing (2).

[0007] Furthermore, the symbols within the parentheses above are symbols attached to the figures in the patent document.

[0008] In conventional bearing assemblies with cooling structures, bearing lock-up can be prevented by suppressing the temperature rise of the bearing's inner ring and rotating shaft through the cooling structure.

[0009] However, when the temperature rise can no longer be suppressed by cooling structures, the bearings lock up. For example, in large-diameter rotating shafts that rotate at high speeds, the circumferential velocity on the outer circumferential surface is extremely high, resulting in a large amount of heat generation in the bearings supporting them. Furthermore, large-diameter rotating shafts experience significant expansion during temperature rise. Therefore, even in conventional bearing assemblies equipped with cooling structures, there are instances where changes in internal preload cannot be suppressed, leading to bearing lockup, and effective countermeasures are desired. Moreover, this applies not only to large-diameter rotating shafts; when changes in internal preload cannot be suppressed, there is a risk of bearing lockup, and effective countermeasures are equally needed. Summary of the Invention

[0010] The present invention was made in view of the above circumstances, with the aim of providing a bearing device that can suppress changes in preload inside the bearing associated with temperature rise in the bearing or rotating shaft.

[0011] To achieve the above objectives, the bearing device of the present invention rotatably supports a rotating shaft by a plurality of bearings, characterized in that it includes an inner spacer, an outer spacer, and an outer spacer cooling structure. The inner spacer is disposed between the adjacent bearings in a manner that contacts the inner rings of each of the adjacent bearings, and the outer spacer is disposed between the adjacent bearings in a manner that contacts the outer rings of each of the adjacent bearings. The outer spacer cooling structure cools the outer spacer.

[0012] The present invention with the above-described structure cools the outer spacer by means of an outer spacer cooling structure, thereby generating a temperature difference between the inner and outer spacers. This allows the inner ring of the bearing to be displaced relative to the outer ring in a direction that reduces the preload inside the bearing, thus suppressing the rise in preload inside the bearing that accompanies the temperature rise of the bearing and the rotating shaft.

[0013] Specifically, preferably, the inner seat is formed as a cylindrical shape along the inner ring of the bearing, and the outer seat is formed as a cylindrical shape along the outer ring of the bearing. Accompanied by the temperature difference generated between the inner and outer seats, the inner seat pushes the inner ring of the bearing in the axial direction, causing the inner ring of the bearing to undergo relative displacement in the axial direction relative to the outer ring.

[0014] This allows the inner ring of the bearing to shift relative to the outer ring in a direction that reduces the preload inside the bearing, thus suppressing the increase in preload inside the bearing that accompanies the temperature rise of the bearing and the rotating shaft.

[0015] Preferably, the aforementioned multiple bearings are configured in a back-to-back arrangement with their backs facing each other.

[0016] When the bearings are arranged in a back-side assembly, the bearing preload is released by pushing the inner ring from the back side. According to the present invention, by cooling the outer spacer via the outer spacer cooling structure, a temperature difference is generated between the inner and outer spacers. This causes the inner spacer to push the bearing's inner ring from the back side towards the axial direction, releasing the bearing preload. In this way, the inner ring of the bearing can be relatively displaced relative to the outer ring in a direction that reduces the preload inside the bearing, thus suppressing the increase in preload inside the bearing that accompanies the temperature rise of the bearing and the rotating shaft.

[0017] Alternatively, the present invention can also be configured as follows: a device body comprising a plurality of bearings, an inner seat and an outer seat, wherein a refrigerant flow path for cooling the plurality of bearings is formed on the device body, and a refrigerant flow path constituting the cooling structure of the outer seat is formed on the device body, and the refrigerant flow paths are connected to each other to circulate the refrigerant.

[0018] Alternatively, the present invention can also be configured as follows: a device body comprising accommodating the aforementioned plurality of bearings, inner and outer seats and housing the magnetic fluid seal, wherein a refrigerant flow path for cooling the magnetic fluid seal is formed on the device body, and a refrigerant flow path constituting the cooling structure of the outer seat is formed on the device body, and the refrigerant flow paths are connected to circulate the refrigerant.

[0019] Alternatively, the present invention can also be configured as follows: a device body comprising accommodating the aforementioned plurality of bearings, inner side seats and outer side seats and housing a heat dissipation section for cooling the aforementioned rotating shaft, wherein a refrigerant flow path for cooling the aforementioned heat dissipation section is formed on the aforementioned device body, and a refrigerant flow path constituting the aforementioned outer side seat cooling structure is formed on the aforementioned device body, and these refrigerant flow paths are connected to circulate the refrigerant.

[0020] Alternatively, the present invention can also be configured as follows: a device body comprising a plurality of bearings, an inner spacer and an outer spacer, and a heat dissipation section for cooling the magnetic fluid seal and the rotating shaft is installed therein; a refrigerant flow path for cooling the plurality of bearings, a refrigerant flow path for cooling the magnetic fluid seal, a refrigerant flow path for cooling the heat dissipation section, and a refrigerant flow path constituting the cooling structure of the outer spacer are formed on the device body; and these refrigerant flow paths are connected to circulate the refrigerant.

[0021] In this way, by connecting the various refrigerant flow paths, the common refrigerant can flow into these refrigerant flow paths, achieving effective cooling.

[0022] As explained above, according to the present invention, the preload change inside the bearing that accompanies the temperature rise of the bearing and the rotating shaft can be suppressed. Attached Figure Description

[0023] Figure 1 This is a front sectional view showing the internal structure of the bearing device according to an embodiment of the present invention.

[0024] Figure 2 This is a perspective view showing a portion of the internal structure of the bearing device according to an embodiment of the present invention cut away.

[0025] Figure 3 This is an exploded perspective view showing the internal structure of the bearing device according to an embodiment of the present invention with a portion cut away.

[0026] Figure 4 This is a perspective view of the bearing device according to an embodiment of the present invention.

[0027] Figure 5A This is a front sectional view showing the structure of the bearing section; Figure 5B and Figure 5C This is a front sectional view of a bearing used to illustrate an example of a preload adjustment mechanism.

[0028] Figure 6 It is an exploded perspective view showing a portion of the outer interseat cooling structure cut off.

[0029] Figure 7A It is a three-dimensional diagram showing the arrangement of multiple electrodes on the outer periphery of a rotating shaft; Figure 7B It is a three-dimensional image of the electrode.

[0030] Figure 8 This is a three-dimensional diagram showing the bearing cooling structure.

[0031] Figure 9 It is an exploded perspective view showing the cooling structure of the rotating shaft in the heat dissipation section with a portion cut off. Detailed Implementation

[0032] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0033] Figure 1 This is a front sectional view showing the internal structure of the bearing device according to an embodiment of the present invention. Figure 2 This is a 3D representation of the image with a portion cut off. Figure 3 This is a decomposed 3D representation of the image with a portion cut off. Figure 4 This is a three-dimensional view of the device's exterior.

[0034] The bearing device of this embodiment is disposed on the outer periphery of the rotating shaft 10, supports the rotating shaft 10 rotatably, and has the function of suppressing the temperature rise of the rotating shaft 10 that accompanies rotation.

[0035] like Figure 4 As shown, the bearing assembly includes a cylindrical assembly body 20, which is disposed on the outer periphery of the rotating shaft 10. Figures 1-3 As shown, the interior of the main body 20 of the device comprises a bearing section 30, a magnetic fluid sealing section 50, and a heat dissipation section 60.

[0036] Figure 5A This is a front sectional view showing the structure of the bearing section.

[0037] The bearing section 30 is a functional part for supporting the rotating shaft 10, which is rotatably supported by the bearing 31.

[0038] like Figure 5A As shown, in the bearing section 30, multiple (two in the figure) bearings 31 are installed, along with an inner seat 32 and an outer seat 33 disposed between these adjacent bearings 31, an outer ring positioning member 34, an outer ring pressing member 35, and an inner ring pressing member 36.

[0039] If the specific installation steps are described, they are installed into the bearing section 30 formed inside the main body 20 in the following order: outer ring positioning component 34, one bearing 31 (lower side of the figure), inner seat 32 and outer seat 33, and the other bearing 31 (upper side of the figure).

[0040] Here, a flange-shaped inner ring positioning portion 11 protruding radially is formed on the outer peripheral surface of the rotating shaft 10. The inner ring of one of the bearings 31, which is installed in the bearing portion 30, abuts against this inner ring positioning portion 11. In addition, the outer ring of one of the bearings 31 abuts against the outer ring positioning member 34.

[0041] An inner ring pressing member 36 mounting portion (inner ring pressing mounting portion 12) is provided on the outer circumferential surface of the rotating shaft 10, and the inner ring pressing member 36 is mounted on this inner ring pressing mounting portion 12. Next, the outer ring pressing member 35 is installed at the inlet of the bearing 31 in the device body 20.

[0042] The inner ring clamping component 36 is a nut structure with internal threads formed on its inner circumferential surface, and is installed in the inner ring clamping mounting part 12, which is formed by external threads, by screwing it in. In addition, the outer ring clamping component 35 is installed on the device body 20 using multiple screws.

[0043] By fitting all structural elements into the interior of the main body 20 of the device, the bearing section 30 is formed.

[0044] The bearing 31 is configured such that an inner ring 37 formed of an annular metal component and an outer ring 38 formed of an annular metal component are arranged coaxially, and a rolling element 39 is inserted between these inner ring 37 and outer ring 38.

[0045] The inner ring 37 is fixed to the rotating shaft 10, and the outer ring 38 is fixed to the main body 20 of the device. The inner ring 37 rotates integrally with the rotating shaft 10, but at this time the rolling element 39 rolls between the outer ring 38 and the inner ring 37.

[0046] Furthermore, various known bearings can be used as bearing 31, such as ball bearings (e.g., deep groove ball bearings) where the rolling elements 39 are made of metal, ceramic, or other spherical bodies, and roller bearings (e.g., tapered roller bearings) where the rolling elements 39 are made of metal rollers. In this embodiment, an angular contact ball bearing that supports radial loads acting in the radial direction and axial loads acting in the axial direction is used as bearing 31.

[0047] The inner spacer 32 is disposed between each bearing 31 in a state of abutting against the respective inner ring 37, and functions as a spacer to adjust the arrangement interval of the inner rings 37 of each bearing 31. In addition, the outer spacer 33 is disposed between each bearing 31 in a state of abutting against the respective outer ring 38, and functions as a spacer to adjust the arrangement interval of the outer rings 38 of each bearing 31.

[0048] The inner ring 37 of each bearing 31 is fixed in a axial direction by the inner ring positioning part 11, the inner side seat 32, and the inner ring pressing member 36. In addition, the outer ring 38 of each bearing 31 is fixed in a axial direction by the outer ring positioning member 34, the outer side seat 33, and the outer ring pressing member 35.

[0049] Moreover, relative to the outer ring 38, outer ring positioning component 34, outer side seat 33 and outer ring pressing component 35 of each bearing 31 fixed on the main body 20, the inner ring 37, inner ring positioning part 11, inner side seat 32 and inner ring pressing component 36 of each bearing 31 rotate as a unit with the rotating shaft 10.

[0050] When the bearing 31 is installed in the bearing section 30 of the main body 20 of the device, the internal preload (i.e., the pressure on the rolling element 39 from the inner ring 37 and the outer ring 38) is adjusted.

[0051] To perform this preload adjustment, the inner ring 37 and outer ring 38 of bearing 31 are configured to be combined in a way that allows for relative displacement in the axial direction. By adjusting their relative positions, the preload inside bearing 31 (hereinafter also referred to as "preload of bearing 31") can be increased or decreased.

[0052] For example, in Figure 5A In the bearing 31 shown, as in Figure 5B and Figure 5C As shown in the enlarged representation, a slope of 38a is formed on the inner circumferential surface of the outer ring 38. Furthermore, Figure 5B and Figure 5C It is configured in Figure 5AAn enlarged view of the cross-section of bearing 31 in the lower right corner. Furthermore, as... Figure 5B As shown, if the inner ring 37 is displaced relative to the outer ring 38 in the direction of arrow A, the pressure acting on the rolling element 39 sandwiched between these inner rings 37 and outer ring 38 is reduced because the inner ring 37 is displaced relative to the direction of the increase of the slope 38a formed on the inner circumferential surface of the outer ring 38.

[0053] On the contrary, such as Figure 5C As shown, if the inner ring 37 is displaced relative to the outer ring 38 in the direction of arrow B, the pressure acting on the rolling element 39 sandwiched between these inner rings 37 and outer ring 38 increases because the inner ring 37 is displaced relative to the direction in which the slope 38a formed on the inner circumferential surface of the outer ring 38 narrows.

[0054] Generally, the preload of bearing 31 is adjusted to the desired pressure by specifying the relative position of outer ring 38 and inner ring 37 by the dimensional difference between the length of inner seat 32 and the length of outer seat 33.

[0055] However, the following situation exists: as the rotating shaft 10 rotates, the temperature of the bearing 31 and the rotating shaft 10 rises, and the bearing 31 and the rotating shaft 10 expand in the radial direction, causing the preload of the bearing 31 to increase. Moreover, there is a danger that the bearing 31 may lock due to this increase in preload, hindering the smooth rotation of the rotating shaft 10.

[0056] Therefore, the bearing device of this embodiment has the function of suppressing the preload change of the bearing 31 that is associated with the temperature rise of the bearing 31 and the rotating shaft 10.

[0057] In order to suppress changes in the preload of the bearing 31, the bearing device of this embodiment has an outer inter-seat cooling structure and a preload adjustment mechanism.

[0058] The outer side seat cooling structure has the following functions: cooling the outer side seat 33, actively setting a temperature difference between it and the inner side seat 32, and absorbing the heat transferred from the bearing 31 to cool the bearing 31 and the rotating shaft 10.

[0059] That is, as the rotating shaft 10 rotates, heat is generated in the bearing 31 by friction between the rolling elements 39, the inner ring 37, and the outer ring 38. This heat is transferred to the inner seat 32 and the outer seat 33. In addition, the rotating shaft 10 also generates heat due to external factors, which is transferred to the inner seat 32 and also to the outer seat 33 via the bearing 31. As a result, the temperature of the inner seat 32 and the outer seat 33 rises.

[0060] Under such conditions, if only the outer spacer 33 is cooled, a large temperature difference will be generated between it and the inner spacer 32. Therefore, the bearing 31 and the rotating shaft 10 are cooled by allowing the heat from the bearing 31 and the rotating shaft 10 to be absorbed through the outer spacer 33.

[0061] In the bearing assembly of this embodiment, an outer inter-seat cooling structure is configured as follows.

[0062] like Figure 6 As shown, a groove 33a extending in the circumferential direction is formed on the outer peripheral surface of the outer interposer 33. When the outer interposer 33 is inserted into the device body 20, the outer peripheral surface of the outer interposer 33 is in close contact with the inner peripheral surface of the device body 20, forming a hollow portion created by the groove 33a (see reference). Figure 1 , Figure 2 and Figure 5A The hollow portion created by the groove 33a thus forms a refrigerant flow path for refrigerant circulation.

[0063] like Figure 1 and Figure 6 As shown, through holes 21a and 21b are formed at two locations on the main body 20, extending from the outer peripheral surface to the inner peripheral surface. These through holes 21a and 21b open into the hollow portion created by the groove 33a. Moreover, refrigerant is supplied from one through hole 21a into the hollow portion created by the groove 33a, and the refrigerant flows within the hollow portion created by the groove 33a and is discharged from the other through hole 21b.

[0064] The refrigerant flowing within the hollow portion created by the groove 33a gradually absorbs heat from the outer slot 33. As a result, the outer slot 33 is cooled, and the temperature rise is suppressed.

[0065] Furthermore, in the bearing device of this embodiment, the following is used: Figure 5A The outer side seat 33, inner side seat 32, inner ring 37 of bearing 31, rolling element 39 and outer ring 38 shown constitute the preload adjustment mechanism as follows.

[0066] That is, if the outer spacer 33 is cooled by the outer spacer cooling structure, a large temperature difference is generated between it and the inner spacer 32, thus suppressing the expansion of the outer spacer 33, but the inner spacer 32 undergoes thermal expansion in the axial direction. Therefore, the inner ring 37 of the bearing 31, which abuts against the inner spacer 32, is pushed by the inner spacer 32. In other words, the inner spacer 32 constitutes a pushing mechanism that pushes the inner ring 37 of the bearing 31 in the axial direction.

[0067] In this way, the inner ring 37 of the bearing 31 is pushed by the inner seat 32, resulting in relative displacement between the inner ring 37 and the outer ring 38 of the bearing 31.

[0068] Here, the multiple bearings 31 mounted on the main body 20 are arranged in a so-called "back-side assembly" with their back faces 31a facing each other, forming a structure in which the inner seat 32 and the outer seat 33 are arranged between these bearings 31. In this way, when the multiple bearings 31 are arranged in a back-side assembly, the preload of the bearings 31 increases when the inner ring 37 is fastened from the front side 31b, and on the other hand, the preload of the bearings 31 is released when the inner ring 37 is pushed from the back side 31a.

[0069] That is, if subjected to a pushing action from the inner seat 32 located in the middle of the plurality of bearings 31, then as Figure 5B As shown, the inner ring 37 is pushed in the direction of arrow A, causing relative displacement between the inner ring 37 and the outer ring 38. Moreover, since the inner circumferential surface of the outer ring 38 forms a slope 38a that expands in the direction of arrow A, the pressure acting on the rolling element 39 sandwiched between these inner rings 37 and outer ring 38 is reduced (i.e., the preload of the bearing 31 is reduced).

[0070] On the other hand, as already described, as the temperature of bearing 31 and rotating shaft 10 rises, bearing 31 and rotating shaft 10 expand in the radial direction (diameter direction), and the preload of bearing 31 increases.

[0071] The preload adjustment mechanism reduces the preload of bearing 31 relative to the increase in preload associated with the temperature rise of bearing 31 and rotating shaft 10 by creating a large temperature difference between the outer seat 33 and the inner seat 32, as described above. Thus, the increase in preload of bearing 31 associated with the temperature rise of bearing 31 and rotating shaft 10 is offset by reducing the preload of bearing 31, thereby suppressing changes in the preload of bearing 31. Furthermore, by suppressing changes in the preload of bearing 31, locking of bearing 31 can be avoided, enabling a rotary bearing that maintains smooth rotation of rotating shaft 10.

[0072] Next, the magnetic fluid sealing part 50 provided inside the main body 20 of the device will be described.

[0073] return Figures 1-3 Inside the main body 20 of the device, a magnetic fluid sealing part 50 is provided side by side with the bearing part 30. The magnetic fluid sealing part 50 is a functional part used to seal the gap located on the outer periphery of the rotating shaft 10 by filling the gap with magnetic fluid and holding the magnetic fluid by magnetic lines of force.

[0074] In the magnetic fluid sealing section 50, a magnetic pole piece called pole piece 51, a magnet 52, and magnetic fluid 53 are installed. The pole piece 51, as... Figure 7A As shown, it is formed into a ring shape by a magnetic material with high magnetic permeability, such as Figure 7BAs shown, multiple (three in the figure) pole pieces 51 arranged side by side in the axial direction are inserted into the magnetic fluid sealing part 50 formed inside the device body 20 (see reference). Figures 1-3 Magnets 52 are arranged side-by-side next to pole pieces 51, and magnetic fluid 53 fills the gap between the inner circumferential surface of pole pieces 51 and the outer circumferential surface of the rotating shaft 10. Moreover, the magnetic lines of force formed by the magnets 52 hold the magnetic fluid 53 in this gap.

[0075] This magnetic fluid seal 50 also generates frictional heat between the magnetic fluid 53 and the rotating shaft 10 in conjunction with the rotation of the rotating shaft 10, causing the temperature to rise. Moreover, as the frictional heat of the magnetic fluid 53 is transferred to the rotating shaft 10, the rotating shaft 10 expands in the radial direction, so the gap between the rotating shaft 10 and the pole piece 51 narrows, posing a risk of hindering the smooth rotation of the rotating shaft 10.

[0076] Therefore, in the bearing device of this embodiment, a cooling structure (magnetic fluid seal cooling structure) is configured for cooling the magnetic fluid seal 50. The heat generated in the magnetic fluid 53 is transferred to the electrode 51, but the magnetic fluid seal cooling structure is configured such that its refrigerant absorbs the heat transferred to the electrode 51 and cools the magnetic fluid 53.

[0077] That is, such as Figure 7A and Figure 7B As shown, a groove 51a extending in the circumferential direction is formed on the outer peripheral surface of the electrode 51. When the electrode 51 is inserted into the device body 20, the outer peripheral surface of the electrode 51 is in close contact with the inner peripheral surface of the device body 20, forming a hollow portion created by the groove 51a (see reference). Figure 1 , Figure 2 The hollow portion created by the groove 51a constitutes a refrigerant flow path for refrigerant circulation.

[0078] like Figure 4 As shown, multiple (six in the figure) through holes 22a, 22b, 22c, 22d, 22e, and 22f are formed on the main body 20 of the device, extending from the outer peripheral surface to the inner peripheral surface. These through holes 22a, 22b, 22c, 22d, 22e, and 22f all open into the hollow portion created by the groove 51a (see reference). Figure 1 Additionally, grooves 51a formed on the outer peripheral surface of each electrode 51, such as... Figure 7A and Figure 7B As shown, the through holes 22a, 22b, and 22c are blocked in a portion of the circumferential direction by the partition wall 51b. With this partition wall 51b as the boundary, half of the through holes 22d, 22e, and 22f open on one side, and the remaining half of the through holes 22d, 22e, and 22f open on the other side.

[0079] Furthermore, although not shown in the diagram, Figure 4 The through holes 22d and 22e, 22b and 22c are connected by piping, and through the piping, the hollow part formed by the groove 51a on the outer peripheral surface of each electrode 51 constitutes a continuous refrigerant flow path.

[0080] Specifically, Figure 4 The through hole 22a shown serves as the refrigerant inlet; if refrigerant is supplied from here, then... Figure 7A The refrigerant enters through the groove 51a of the first electrode 51 shown and flows within the hollow portion created by the groove 51a. Then, the refrigerant flows through another through-hole 22d (see reference 22a) that opens through the groove 51a. Figure 4 ) Enters through the adjacent through-hole 22e via the piping, towards Figure 7A The refrigerant is supplied through the groove 51a of the second electrode 51 shown, flowing within the hollow portion created by the groove 51a. Then, the refrigerant flows through another through-hole 22b (see reference 22a) opening in the groove 51a. Figure 4 ) Enters through the adjacent through hole 22c via the piping, towards Figure 7A The refrigerant is supplied through the groove 51a of the third electrode 51 shown, flowing within the hollow portion created by the groove 51a. Then, the refrigerant is discharged from the through-hole 22f (see reference). Figure 4 ).

[0081] As the refrigerant flows through the refrigerant flow path, it absorbs heat from the electrode 51, cooling the magnetic fluid 53.

[0082] Next, the bearing cooling structure provided on the main body 20 of the device will be described.

[0083] return Figures 1-3 A groove 20a is formed on the outer peripheral surface of the main body 20 of the device. This groove 20a, as... Figure 8 As shown, a spiral track is formed on the outer peripheral surface of the device body 20. On the outer peripheral surface of the device body 20 where the groove 20a is formed, as shown... Figures 1-3 As shown, a cylindrical covering component 23 is embedded, and the inner circumferential surface of this covering component 23 is in close contact with the outer circumferential surface of the device body 20, forming a hollow portion that extends in a spiral shape by the groove 20a. The hollow portion formed by the groove 20a constitutes a refrigerant flow path for circulating the refrigerant.

[0084] like Figure 2 and Figure 3As shown, two through holes 23a and 23b are formed on the covering component 23, extending from the outer peripheral surface to the inner peripheral surface. One through hole 23a opens near the beginning of the spiral hollow portion generated by the groove 20a, and the other through hole 23b opens near the end of the spiral hollow portion generated by the groove 20a.

[0085] Furthermore, the through hole 23a, which opens near the beginning of the hollow portion, is connected to the through hole 22f of the magnetic fluid sealing part 50 described above by a pipe (not shown) (see reference). Figure 4 Thus, the refrigerant flows in the cooling path of the sealing part, and the refrigerant discharged from the through hole 22f is supplied from the through hole 23a to the hollow part created by the groove 20a via the piping.

[0086] Furthermore, the refrigerant supplied through the through hole 23a flows in the spiral hollow portion created by the groove 20a and is discharged through the other through hole 23b (see reference). Figure 4 ).

[0087] The refrigerant flowing within the spiral-shaped hollow portion created by the groove 20a gradually absorbs heat from the device body 20. This cools the multiple bearings 31 installed within the device body 20.

[0088] Additionally, refer to Figure 1 and Figure 6 The two through holes 21a and 21b, which are the hollow openings created by the groove 33a of the outer seat 33 as described above, also open into the spiral hollow openings created by the groove 20a, respectively. A portion of the refrigerant flowing in the spiral hollow is supplied from one through hole 21a into the hollow opening created by the groove 33a of the outer seat 33, flows in the hollow, and returns to the spiral hollow from the other through hole 21b.

[0089] Figure 6 The through holes 21a and 21b shown are respectively positioned at points symmetrical about the central axis (within 180 degrees). Moreover, the refrigerant supplied from one through hole 21a flows in branches to the right and left in the groove 33a, and is discharged from the other through hole 21b, returning to the spiral hollow part created by the groove 33a.

[0090] Alternatively, the structure can be configured such that through holes 21a and 21b are arranged side-by-side near the partition wall in the circumferential direction. Refrigerant supplied from one through hole 21a flows in one direction within the groove 33a and exits from the other through hole 21b. This configuration eliminates the impact caused by the confluence of refrigerant in the through hole 21b, allowing for smooth refrigerant discharge.

[0091] Next, the heat dissipation section 60 installed inside the main body 20 of the device will be described.

[0092] return Figures 1-3 Inside the main body 20 of the device, a heat dissipation section 60 is arranged side by side with the bearing section 30 on the opposite side of the magnetic fluid seal section 50. The heat dissipation section 60 is a functional part for absorbing the heat accumulated in the rotating shaft 10 and directly cooling the rotating shaft 10. In this heat dissipation section 60, a structure for cooling the rotating shaft 10 is formed.

[0093] That is, such as Figure 9 As shown, an annular shaft heat absorption member 61 is installed in the heat dissipation section 60 of the main body 20 of the device. The inner circumferential surface of the shaft heat absorption member 61 is disposed on and in gentle contact with the outer circumferential surface of the rotating shaft 10. As a result, heat from the rotating shaft 10 is transferred to the shaft heat absorption member 61.

[0094] A groove 61a extending in the circumferential direction is formed on the outer peripheral surface of the shaft heat absorption component 61. When the shaft heat absorption component 61 is installed inside the device body 20, the outer peripheral surface of the shaft heat absorption component 61 is in close contact with the inner peripheral surface of the device body 20, forming a hollow portion created by the groove 61a (see reference). Figure 1 , Figure 2 and Figure 9 The hollow portion created by the groove 61a forms a refrigerant flow path for refrigerant circulation.

[0095] Through holes 24a and 24b are formed at two locations on the main body 20, extending from the outer peripheral surface to the inner peripheral surface. These through holes 24a and 24b open into the hollow portion created by the groove 61a. One of the through holes 24a is connected to a through hole 23b formed on the covering component 23 of the bearing cooling structure via a pipe (not shown). Thus, refrigerant discharged from the through hole 23b in the bearing cooling structure is supplied to one of the through holes 24a via a pipe (not shown) (see reference). Figure 4 ).

[0096] Furthermore, refrigerant is supplied from this through hole 24a into the hollow portion created by the groove 61a, where the refrigerant flows and is discharged from the other through hole 24b.

[0097] The refrigerant flowing within the hollow portion created by the groove 61a gradually absorbs the heat transferred from the rotating shaft 10 to the shaft heat absorption member 61. This cools the rotating shaft 10.

[0098] Here, Figure 9 The through holes 24a and 24b shown are also... Figure 6Similarly, the through holes 21a and 21b shown are respectively positioned in a point-symmetrical manner about the central axis (within a 180-degree radius). Moreover, the refrigerant supplied from one through hole 24a flows in a branching manner, turning to the right and to the left in the groove 61a, and is discharged from the other through hole 24b.

[0099] Alternatively, the structure can be configured such that through holes 24a and 24b are arranged side-by-side in the circumferential direction, sandwiching the partition wall. Refrigerant supplied from one through hole 24a flows in one direction within the groove 61a and exits from the other through hole 24b. This configuration eliminates the impact caused by the confluence of refrigerant in the through hole 24b, allowing for smooth refrigerant discharge.

[0100] like Figure 9 As shown, a through hole 24b formed on the other side of the device body 20 is connected to a refrigerant cooling circulation device (not shown) that is also provided on the bearing assembly via a pipe (not shown). The refrigerant discharged from this through hole 24b is supplied to the refrigerant cooling circulation device (not shown), where it is cooled and then circulated back to the through hole 22a of the sealing part cooling structure.

[0101] Here, refer to Figure 4 If the refrigerant circulation path is explained again, the refrigerant supplied to the through hole 22a of the sealing cooling structure by the refrigerant cooling circulation device not shown in the figure, in Figure 1 and Figure 2 The heat transferred from the rotating shaft 10 to the electrode 51 flows through the hollow portion formed by the groove 51a in the cooling structure of the sealing part, as shown.

[0102] Next, the refrigerant is supplied from the through hole 22f of the sealing cooling structure to the through hole 23a of the bearing cooling structure, and flows in the spiral hollow part formed by the groove 20a on the bearing cooling structure, absorbing the heat transferred from the rotating shaft 10 to the device body 20.

[0103] Furthermore, a portion of the refrigerant is also supplied from the through hole 21a formed on the device body 20 to the hollow portion formed by the groove 33a on the outer side cooling structure, where it flows and absorbs the heat transferred from the bearing 31 and the rotating shaft 10 to the outer side cooling structure. Moreover, the refrigerant returns from the through hole 21b formed on the other side of the device body 20 to the spiral hollow portion formed by the groove 20a on the bearing cooling structure.

[0104] Next, the refrigerant is supplied from the through hole 23b of the bearing cooling structure to the through hole 24a of the heat dissipation section 60, flowing in the hollow portion formed by the groove 61a in the heat dissipation section 60, absorbing the heat transferred from the rotating shaft 10 to the shaft heat absorption member 61. Then, the refrigerant returns from the through hole 24b of the heat dissipation section 60 to a refrigerant cooling circulation device (not shown), and after being cooled, is supplied again to the through hole 22a of the sealing part cooling structure.

[0105] The bearing device of this embodiment, as described above, has a bearing cooling structure, a magnetic fluid seal cooling structure, a cooling structure for the rotating shaft 10 in the heat dissipation section 60, and an outer seat cooling structure. Therefore, the heat from the bearing 31 and the rotating shaft 10 is absorbed by the refrigerant circulating in each cooling structure, and the bearing 31 and the rotating shaft 10 can be effectively cooled.

[0106] Furthermore, since the refrigerant flows through the refrigerant flow paths provided on each cooling structure in a connected manner, the refrigerant circulation control can be simplified, and further effective cooling can be achieved.

[0107] Furthermore, the present invention is not limited to the above-described embodiments, and various modifications and applications can be implemented as needed.

[0108] For example, a preload adjustment mechanism used to reduce the preload inside a bearing is not limited to... Figure 5B and Figure 5C As shown, the structure utilizing a slope of 38a allows for various structures that reduce the preload inside the bearing by accommodating the relative displacement between the outer and inner rings of the bearing.

[0109] In the above embodiments, in order to form a refrigerant flow path for the bearing cooling structure, a groove 20a is formed on the outer peripheral surface of the device body 20. However, a groove can also be formed on the covering component 23 as a refrigerant flow path. Alternatively, grooves can be formed on both the outer peripheral surface of the device body 20 and the covering component 23 to form a refrigerant flow path.

[0110] Similarly, instead of the groove 33a forming the refrigerant flow path in the cooling structure of the outer interseat, a groove can be formed on the inner circumferential surface of the device body 20 that contacts the outer interseat 33 as a refrigerant flow path. Alternatively, grooves can be formed on both the outer interseat 33 and the inner circumferential surface of the device body 20 to form a refrigerant flow path.

[0111] Similarly, instead of the groove 51a forming the refrigerant flow path in the cooling structure of the magnetic fluid sealing part, a groove can be formed on the inner peripheral surface of the device body 20 that contacts the electrode 51 as a refrigerant flow path. Alternatively, grooves can be formed on both the inner peripheral surfaces of the electrode 51 and the device body 20 to form a refrigerant flow path.

[0112] Similarly, instead of the groove 61a forming the refrigerant flow path in the heat dissipation section 60, a groove can be formed on the inner circumferential surface of the device body 20 that contacts the axial heat absorption member 61 as a refrigerant flow path. Alternatively, grooves can be formed on both the inner circumferential surfaces of the axial heat absorption member 61 and the device body 20 to form a refrigerant flow path.

[0113] In addition, in the above-described embodiments, based on the structure of cooling the outer side seat 33, there is a structure for cooling the bearing 31, a structure for cooling the magnetic fluid seal 50, and a cooling structure for the rotating shaft 10 in the heat dissipation section 60, but some of them can be omitted.

[0114] In addition, in the above embodiment, the refrigerant is supplied from the magnetic fluid seal 50 to the outer seat 33 through the periphery of the device body 20, and then flows from the periphery of the device body 20 to the heat dissipation section 60. However, the flow path of the refrigerant is not limited to this and can be appropriately changed as needed.

Claims

1. A bearing assembly comprising a plurality of bearings that rotatably support a rotating shaft, characterized in that, It features an inner inter-seat, an outer inter-seat, an outer inter-seat cooling structure, and a main body. The inner spacer is positioned between the adjacent bearings in such a way that it contacts the inner rings of each of the aforementioned bearings. The outer spacer is positioned between the adjacent bearings in such a way that it contacts the outer rings of each of the aforementioned bearings. The outer interspindle cooling structure cools the aforementioned outer interspindle. The main body of the device houses the aforementioned multiple bearings, inner and outer spacers, and also incorporates the magnetic fluid sealing part. A refrigerant flow path for cooling the magnetic fluid seal and a refrigerant flow path for cooling the plurality of bearings are formed on the main body of the aforementioned device. The refrigerant flow path for cooling the magnetic fluid seal and the refrigerant flow path for cooling the multiple bearings are connected in series to circulate the refrigerant.

2. A bearing assembly comprising a plurality of bearings that rotatably support a rotating shaft, characterized in that, It features an inner inter-seat, an outer inter-seat, an outer inter-seat cooling structure, and a main body. The inner spacer is positioned between the adjacent bearings in such a way that it contacts the inner rings of each of the aforementioned bearings. The outer spacer is positioned between the adjacent bearings in such a way that it contacts the outer rings of each of the aforementioned bearings. The outer interspindle cooling structure cools the aforementioned outer interspindle. The main body of the device houses the aforementioned multiple bearings, inner and outer spacers, and includes a heat dissipation section for cooling the aforementioned rotating shaft. A refrigerant flow path for cooling the heat dissipation section and a refrigerant flow path for cooling the plurality of bearings are formed on the main body of the aforementioned device. The refrigerant flow path for cooling the heat dissipation section and the refrigerant flow path for cooling the multiple bearings are connected in series to circulate the refrigerant.

3. A bearing assembly comprising a plurality of bearings that rotatably support a rotating shaft, characterized in that, It features an inner inter-seat, an outer inter-seat, an outer inter-seat cooling structure, and a main body. The inner spacer is positioned between the adjacent bearings in such a way that it contacts the inner rings of each of the aforementioned bearings. The outer spacer is positioned between the adjacent bearings in such a way that it contacts the outer rings of each of the aforementioned bearings. The outer interspindle cooling structure cools the aforementioned outer interspindle. The main body of the device houses the aforementioned multiple bearings, inner and outer spacers, and also incorporates a magnetic fluid seal and a heat dissipation section for cooling the aforementioned rotating shaft. The main body of the device has a refrigerant flow path for cooling the multiple bearings, a refrigerant flow path for cooling the magnetic fluid seal, and a refrigerant flow path for cooling the heat dissipation section. These refrigerant flow paths are connected in series to circulate the refrigerant.

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