Pre-tightening switching structure

Abstract

The utility model relates to the field of bearing pre-tightening, in particular to a pre-tightening switching structure which comprises a fixing part, a supporting part, a first sliding part and a second sliding part, the supporting part is connected to the fixing part, the first sliding part is slidably connected to the fixing part, the second sliding part is slidably connected to the fixing part, and the sliding direction of the second sliding part is parallel to the sliding direction of the first sliding part. The second sliding piece is located between the supporting piece and the first sliding piece, the projection area of the second sliding piece on the face A is not equal to the projection area of the first sliding piece on the face A. The face A is perpendicular to the sliding direction of the first sliding piece, and the side, away from the second sliding piece, of the first sliding piece is used for abutting against the bearing. Under the condition that fluid is not injected, the acting force of the first sliding piece on the bearing is minimum; when the fluid pressure intensity is a fixed value, fluid is injected between the supporting piece and the second sliding piece or between the second sliding piece and the first sliding piece so as to control the change of the acting force of the first sliding piece on the bearing; and the use requirements of multiple working conditions are met.

Description

Technical Field

[0001] The present application relates to the field of bearing preloading, and particularly to a preloading switching structure. Background Art

[0002] The high-speed operation of the machine tool spindle centered on the machining center is very obvious, and the highest d m n value (d m : rolling element center diameter: mm, n: rotational speed min -1 ) can reach 250 - 380x10 when using oil-air lubrication. 4 Considering from the spindle aspect, from low-speed operation to high-speed operation, the bearing is required to have good rigidity. Therefore, by applying the most appropriate preloading to the bearing, high-speed and high-rigidity functions can be provided.

[0003] In the case of heavy preloading, the bearing has a large frictional force and is suitable for low-speed operation; in the case of light preloading, the bearing has a small frictional force and is suitable for high-speed operation.

[0004] Bearing preloading usually adopts the constant-pressure preloading (spring preloading) method, which cannot meet the usage requirements of multiple working conditions. Utility Model Content

[0005] In order to meet the usage requirements of multiple working conditions, the present application provides a preloading switching structure.

[0006] A preloading switching structure provided by the present application adopts the following technical solutions:

[0007] A preloading switching structure includes a fixing member, a supporting member, a first sliding member, and a second sliding member.

[0008] The supporting member is connected to the fixing member.

[0009] The first sliding member is slidably connected to the fixing member.

[0010] The second sliding member is slidably connected to the fixing member, the sliding direction of the second sliding member is parallel to the sliding direction of the first sliding member, and the second sliding member is located between the supporting member and the first sliding member.

[0011] Fluids are to be injected between the supporting member and the second sliding member, and between the second sliding member and the first sliding member.

[0012] The projected area of the second sliding member on plane A is not equal to the projected area of the first sliding member on plane A, and plane A is perpendicular to the sliding direction of the first sliding member.

[0013] The fixing member is used for installing the spindle, and makes the axial direction of the spindle parallel to the sliding direction of the first sliding member. The fixing member is used for axial fixation with the spindle.

[0014] One side of the first sliding member facing away from the second sliding member is used to abut against the bearing.

[0015] By adopting the above technical solution, in the case of not injecting fluid, the acting force (preload force) of the first sliding member on the bearing is the smallest; when the fluid pressure is a fixed value, fluid is injected between the support member and the second sliding member or between the second sliding member and the first sliding member to control the change of the acting force (preload force) of the first sliding member on the bearing; so as to meet the usage requirements of multiple working conditions.

[0016] Preferably, a first positioning member is further included.

[0017] The first positioning member is connected to the fixing member.

[0018] The first positioning member is used for the first sliding member to abut against, so as to limit the maximum distance between the first sliding member and the support member.

[0019] By adopting the above technical solution, in the case of injecting fluid between the second sliding member and the first sliding member, the maximum value of the preload force is limited.

[0020] Preferably, a second positioning member is further included.

[0021] The second positioning member is connected to the fixing member.

[0022] The second positioning member is used for the second sliding member to abut against, so as to limit the maximum distance between the second sliding member and the support member.

[0023] When the distance between the second sliding member and the support member is at the maximum value, there is no mutual acting force between the surface of the first sliding member facing away from the second sliding member and the first positioning member.

[0024] By adopting the above technical solution, in the case of injecting fluid between the support member and the second sliding member, the maximum value of the preload force is limited; and it is ensured that the acting force of the fluid on the second sliding member is all transmitted to the bearing.

[0025] Preferably, a second positioning member is further included.

[0026] The second positioning member is connected to the fixing member.

[0027] The second positioning member is used for the second sliding member to abut against, so as to limit the maximum distance between the second sliding member and the support member.

[0028] By adopting the above technical solution, in the case of injecting fluid between the support member and the second sliding member, the maximum value of the preload force is limited.

[0029] Preferably, between the opposite surfaces of the first sliding member and the second sliding member, a first injection groove is provided at one surface.

[0030] By adopting the above technical solution, the tight fit between the opposite surfaces of the first sliding member and the second sliding member is avoided, so as to facilitate the inflow of fluid into the first injection groove.

[0031] Preferably, the surface of the second sliding member facing the first sliding member is a flat surface.

[0032] By adopting the above technical solution, between the opposite surfaces of the first sliding member and the second sliding member, one surface is designed as a flat surface, which is convenient for fluid pressure relief.

[0033] Preferably, between the opposite surfaces of the second sliding member and the support member, a second injection groove is provided at one surface.

[0034] By adopting the above technical solution, the tight fit between the opposite surfaces of the second sliding member and the support member is avoided, so as to facilitate the inflow of fluid into the second injection groove.

[0035] Preferably, the surface of the second sliding member facing the support member is a flat surface.

[0036] By adopting the above technical solution, between the opposite surfaces of the second sliding member and the support member, one surface is designed as a flat surface, which is convenient for fluid pressure relief.

[0037] Preferably, a working groove is provided at the surface of the first sliding member facing away from the second sliding member.

[0038] When fluid is injected into the working groove, the force of the fluid on the first sliding member causes the first sliding member to have a tendency to approach the second sliding member.

[0039] By adopting the above technical solution, when no fluid is injected or fluid is injected between the support member and the second sliding member, the first sliding member is always pressed against the second sliding member to ensure correct switching between these two states.

[0040] Preferably, an elastic member is further included.

[0041] The elastic member is located on the side of the first sliding member facing away from the second sliding member, and the elastic member is used to press against the bearing.

[0042] By adopting the above technical solution, it is beneficial to keep the force on the bearing stable and beneficial to the stable operation of the bearing.

[0043] In summary, the present application includes at least one of the following beneficial technical effects:

[0044] 1. Without injecting fluid, the force (preload) of the first sliding member on the bearing is minimized; when the fluid pressure is constant, fluid is injected between the support member and the second sliding member or between the second sliding member and the first sliding member to control the change in the force (preload) of the first sliding member on the bearing, so as to meet the usage requirements under multiple working conditions.

[0045] 2. The first positioning member and the second positioning member are used to respectively limit the maximum values of the preloads in two states.

[0046] 3. An elastic member is provided to facilitate the stability of the force on the bearing and the stable operation of the bearing. Description of the Drawings

[0047] Figure 1 It is a schematic diagram of the preload switching structure under the condition of the maximum preload.

[0048] Figure 2 It is a schematic diagram of the preload switching structure under the condition of medium preload.

[0049] Figure 3 It is a schematic diagram of the preload switching structure under the condition of the minimum preload.

[0050] Description of the Reference Numerals: 1. Fixed member; 11. First flow channel; 12. Second flow channel; 2. Support member; 21. Second injection groove; 22. Second accommodation groove; 3. First sliding member; 31. Positioning step surface; 32. First injection groove; 33. First accommodation groove; 34. Mounting step surface; 35. Working groove; 4. Second sliding member; 5. First positioning member; 51. First positioning cylinder; 52. First positioning ring; 6. Second positioning member; 61. Second positioning cylinder; 62. Fixed ring; 63. Second positioning ring; 7. Elastic member. Detailed Embodiment

[0051] The following further elaborates on this application in detail with reference to the drawings.

[0052] Refer to Figure 1 , the spindle structure includes a spindle box, a spindle, and a bearing. The spindle is rotatably connected to the spindle box through the bearing, and the spindle is axially fixed between the spindle and the spindle box. The bearing adopts an angular contact ball bearing or a tapered roller bearing, and the spindle is axially fixed between the inner ring of the bearing.

[0053] The embodiment of this application discloses a preload switching structure, including a fixed member 1, a support member 2, a first sliding member 3, and a second sliding member 4.

[0054] The fixed member 1 is used for the installation of the spindle and is axially fixed to the spindle. In this embodiment: the fixed member 1 is cylindrical, the spindle is coaxial with the fixed member 1; the fixed member 1 is integrally formed with the spindle box.

[0055] The support member 2 is fixedly connected to the fixing member 1. In this embodiment: the support member 2 is annular, and the support member 2 is coaxially embedded in the fixing member 1; the inner circumference of the fixing member 1 is provided with a step surface, and the support member 2 is attached to the step surface; the support member 2 is sleeved outside the main shaft.

[0056] The first sliding member 3 is slidably connected to the fixing member 1. In this embodiment: the first sliding member 3 is cylindrical, coaxially slidably embedded in the fixing member 1, and located on the side of the supporting member 2 away from the step surface; the first sliding member 3 is sleeved outside the main shaft.

[0057] The second sliding member 4 is slidably connected to the fixed member 1, and the sliding direction of the second sliding member 4 is parallel to the sliding direction of the first sliding member 3. The second sliding member 4 is located between the support member 2 and the first sliding member 3. In this embodiment: the second sliding member 4 is annular, and the second sliding member 4 is coaxially slidably embedded in the fixed member 1; the second sliding member 4 is sleeved outside the main shaft.

[0058] The projection area of ​​the second sliding member 4 on the surface A is not equal to the projection area of ​​the first sliding member 3 on the surface A, and the surface A is perpendicular to the sliding direction of the first sliding member 3. In this embodiment: the outer diameter of the second sliding member 4 is equal to the outer diameter of the first sliding member 3, and the inner diameter of the second sliding member 4 is greater than the inner diameter of the first sliding member 3.

[0059] The preload switching structure further includes a first positioning member 5 and a second positioning member 6 .

[0060] The first positioning member 5 is fixedly connected to the fixing member 1 . The first positioning member 5 is used for the first sliding member 3 to abut against, so as to limit the maximum distance between the first sliding member 3 and the supporting member 2 .

[0061] In this embodiment: the first positioning member 5 includes a coaxial first positioning cylinder 51 and a first positioning ring 52; the first positioning cylinder 51 is coaxially embedded in the fixing member 1; one end of the first positioning cylinder 51 is fixedly connected to the supporting member 2; the first positioning cylinder 51 is sleeved outside the main shaft; the first positioning ring 52 is located at the outer peripheral surface of the other end of the first positioning cylinder 51, and the surface of the first positioning ring 52 facing the supporting member 2 is used for the first sliding member 3 to resist;

[0062] One end of the first sliding member 3 close to the support member 2 slides outside the first positioning tube 51; the inner periphery of the first sliding member 3 is provided with a positioning step surface 31, and the positioning step surface 31 is used to interfere with the surface of the first positioning ring 52 facing the support member 2; the end of the first sliding member 3 away from the support member 2 is located on the side of the first positioning ring 52 away from the support member 2.

[0063] The second positioning member 6 is fixedly connected to the fixing member 1 . The second positioning member 6 is used for the second sliding member 4 to abut against, so as to limit the maximum distance between the second sliding member 4 and the supporting member 2 .

[0064] In this embodiment: The second positioning member 6 includes a coaxial second positioning cylinder 61, a fixing ring 62, and a second positioning ring 63; the second positioning cylinder 61 is coaxially embedded in the fixing member 1; the second positioning cylinder 61 is sleeved outside the first positioning cylinder 51; the fixing ring 62 is located at the inner circumference of one end of the second positioning cylinder 61, and the bolt sequentially passes through the support member 2 and the fixing ring 62 and is then threadedly connected to the first positioning cylinder 51 (that is, one end surface of the fixing ring 62 abuts against the support member 2, and the other end surface of the fixing ring 62 abuts against the end surface of the first positioning cylinder 51); the second positioning ring 63 is located at the outer peripheral surface of the other end of the second positioning cylinder 61, and the surface of the second positioning ring 63 facing the support member 2 is for the second sliding member 4 to abut against, and there is a gap between the surface of the second positioning ring 63 facing away from the support member 2 and the first positioning ring 52; the second sliding member 4 is slidably sleeved outside the second positioning cylinder 61.

[0065] Referring to Figure 2 , when the distance between the second sliding member 4 and the support member 2 is at its maximum value, there is no interaction force between the surface of the first sliding member 3 facing away from the second sliding member 4 and the first positioning member 5.

[0066] In this embodiment: Referring to Figure 3 , when the second sliding member 4 abuts against the support member 2 and the first sliding member 3 abuts against the second sliding member 4, the first sliding member 3 is not in contact with either the first positioning ring 52 or the second positioning ring 63;

[0067] Referring to Figure 2 , when the second sliding member 4 abuts against the second positioning ring 63 and the first sliding member 3 abuts against the second sliding member 4, the first sliding member 3 is not in contact with either the first positioning ring 52 or the second positioning ring 63.

[0068] Referring to Figure 2 , a fluid is to be injected between the support member 2 and the second sliding member 4. Between the surfaces of the second sliding member 4 and the support member 2 facing each other, a second injection groove 21 is provided on one surface and the other surface is a flat surface.

[0069] In this embodiment: The surface of the second sliding member 4 facing the support member 2 is a flat surface; the second injection groove 21 is located on the surface of the support member 2 facing the second sliding member 4, the second injection groove 21 is annular, the second injection groove 21 is coaxial with the support member 2, and the outer diameter of the second injection groove 21 is equal to the outer diameter of the support member 2; a second accommodation groove 22 is also coaxially provided on the surface of the support member 2 facing the second sliding member 4, the inner diameter of the second accommodation groove 22 is larger than the outer diameter of the second positioning cylinder 61, and the outer diameter of the second accommodation groove 22 is smaller than the inner diameter of the second injection groove 21.

[0070] Referring to Figure 1The space between the second sliding member 4 and the first sliding member 3 is used to inject fluid. The fluid can be hydraulic oil or compressed gas. Between the surfaces opposite to each other of the first sliding member 3 and the second sliding member 4, one surface is provided with a first injection groove 32, and the other surface is a plane.

[0071] In this embodiment: the surface of the second sliding member 4 facing the first sliding member 3 is a plane; the first injection groove 32 is located on the surface of the first sliding member 3 facing the second sliding member 4, the first injection groove 32 is annular, the first injection groove 32 is coaxial with the first sliding member 3, and the outer diameter of the first injection groove 32 is equal to the outer diameter of the first sliding member 3; the first sliding member 3 is also coaxially provided with a first accommodating groove 33 on the surface facing the second sliding member 4, the inner diameter of the first accommodating groove 33 is equal to the outer diameter of the first positioning cylinder 51, and the outer diameter of the first accommodating groove 33 is smaller than the inner diameter of the first injection groove 32.

[0072] Reference Figure 1 and Figure 2 The fixing member 1 is further provided with a first flow channel 11 and a second flow channel 12. The first flow channel 11 is used to connect to the first injection groove 32, and the second flow channel 12 is used to connect to the second injection groove 21. The first flow channel 11 and the second flow channel 12, the first flow channel 11 and the second injection groove 21, and the second flow channel 12 and the first injection groove 32 are not connected.

[0073] The preload switching structure further includes an elastic member 7. The elastic member 7 is located on a side of the first sliding member 3 that is away from the second sliding member 4, and the elastic member 7 is used to press against the bearing.

[0074] In this embodiment: the inner periphery of the first sliding member 3 is also provided with a mounting step surface 34, and the mounting step surface 34 is located on the side of the first positioning ring 52 away from the support member 2; the elastic member 7 abuts against the mounting step surface 34; the outer ring of the bearing is coaxially embedded in the first sliding member 3, and the outer ring of the bearing and the first sliding member 3 can be a clearance fit; the elastic member 7 also abuts against the outer ring of the bearing; the elastic member 7 can adopt a disc spring.

[0075] A working groove 35 is coaxially disposed on the outer circumference of the first sliding member 3 (the outer diameter of the working groove 35 is equal to the outer diameter of the first sliding member 3). In this embodiment, the inner diameters of the first injection groove 32, the second injection groove 21, and the working groove 35 are all equal.

[0076] When fluid is injected into the working groove 35 , the fluid exerts a force on the first sliding member 3 so that the first sliding member 3 tends to approach the second sliding member 4 .

[0077] The implementation principle of a preload switching structure in the present application embodiment is as follows: Figure 3, when the main shaft rotates at a high speed, only fluid is injected into the working groove 35, so that the second sliding member 4 abuts against the support member 2 and the first sliding member 3 abuts against the second sliding member 4, then the acting force (preloading force) of the first sliding member 3 on the bearing is the smallest;

[0078] Refer to Figure 2 , when the main shaft rotates at a medium speed, fluid is injected into the working groove 35, the second injection groove 21, and the second accommodation groove 22, so that the second sliding member 4 abuts against the second positioning ring 63 and the first sliding member 3 abuts against the second sliding member 4, then the acting force (preloading force) of the first sliding member 3 on the bearing is medium;

[0079] Refer to Figure 1 , when the main shaft rotates at a low speed, fluid is injected into the working groove 35, the first injection groove 32, and the first accommodation groove 33, so that the first sliding member 3 abuts against the first positioning ring 52, then the acting force (preloading force) of the first sliding member 3 on the bearing is the largest;

[0080] To meet the usage requirements of multiple working conditions.

[0081] The above are all the preferred embodiments of the present application, and the protection scope of the present application is not limited hereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A preload switching structure, characterized in that: It comprises a fixing member (1), a supporting member (2), a first sliding member (3) and a second sliding member (4), The support member (2) is connected to the fixing member (1). The first sliding member (3) is slidably connected to the fixing member (1). The second sliding member (4) is slidably connected to the fixing member (1); the sliding direction of the second sliding member (4) is parallel to the sliding direction of the first sliding member (3); the second sliding member (4) is located between the supporting member (2) and the first sliding member (3); The space between the support member (2) and the second sliding member (4) is used to inject fluid, and the space between the second sliding member (4) and the first sliding member (3) is used to inject fluid. The projection area of ​​the second sliding member (4) on the surface A is not equal to the projection area of ​​the first sliding member (3) on the surface A, and the surface A is perpendicular to the sliding direction of the first sliding member (3). The fixing member (1) is used for mounting the main shaft and making the axial direction of the main shaft parallel to the sliding direction of the first sliding member (3). The fixing member (1) is used for axial fixing with the main shaft. The side of the first sliding member (3) facing away from the second sliding member (4) is used to press against the bearing.

2. The preload switching structure according to claim 1, characterized in that: It also includes a first positioning member (5), The first positioning member (5) is connected to the fixing member (1). The first positioning member (5) is used for the first sliding member (3) to abut against, so as to limit the maximum distance between the first sliding member (3) and the supporting member (2).

3. The preload switching structure according to claim 2, characterized in that: It also includes a second positioning member (6), The second positioning member (6) is connected to the fixing member (1). The second positioning member (6) is used for the second sliding member (4) to abut against, so as to limit the maximum distance between the second sliding member (4) and the supporting member (2). When the distance between the second sliding member (4) and the support member (2) is at a maximum value, there is no interaction force between the surface of the first sliding member (3) facing away from the second sliding member (4) and the first positioning member (5).

4. The preload switching structure according to claim 1, characterized in that: It also includes a second positioning member (6), The second positioning member (6) is connected to the fixing member (1). The second positioning member (6) is used for the second sliding member (4) to abut against, so as to limit the maximum distance between the second sliding member (4) and the supporting member (2).

5. The preload switching structure according to claim 1, characterized in that: A first injection groove (32) is provided on one surface between the surfaces opposite to each other of the first sliding member (3) and the second sliding member (4).

6. The preload switching structure according to claim 5, characterized in that: The surface of the second sliding member (4) facing the first sliding member (3) is a plane.

7. The preload switching structure according to claim 1, characterized in that: A second injection groove (21) is provided on one surface between the surfaces opposite to the second sliding member (4) and the supporting member (2).

8. The preload switching structure according to claim 7, characterized in that: The surface of the second sliding member (4) facing the supporting member (2) is a plane.

9. The preload switching structure according to claim 1, characterized in that: A working groove (35) is provided on a surface of the first sliding member (3) facing away from the second sliding member (4). When fluid is injected into the working groove (35), the fluid exerts a force on the first sliding member (3) so that the first sliding member (3) tends to approach the second sliding member (4).

10. The preload switching structure according to claim 1, characterized in that: It also includes an elastic member (7), The elastic member (7) is located on a side of the first sliding member (3) facing away from the second sliding member (4), and the elastic member (7) is used to press against the bearing.

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