Pre-tightening assembly of electric spindle, pre-tightening testing device and electric spindle

Abstract

The invention provides a pre-tightening assembly of an electric spindle, a pre-tightening testing device and the electric spindle. The pre-tightening assembly comprises a bearing limiting sleeve, a pre-tightening sleeve, a threaded sleeve and an elastic piece. The bearing limiting sleeve is arranged in a shaft sleeve of the motorized spindle, the pre-tightening sleeve is arranged in the bearing limiting sleeve, a first mounting cavity is formed between the pre-tightening sleeve and the bearing limiting sleeve, the first mounting cavity is used for mounting the rotor, the rotor is rotationally connected with the bearing limiting sleeve through a first bearing, part of the threaded sleeve is arranged in the pre-tightening sleeve, and the threaded sleeve is in threaded connection with the pre-tightening sleeve. The elastic piece is connected between the threaded sleeve and the shaft sleeve and can operate the threaded sleeve to move in the axial direction of the bearing limiting sleeve so as to adjust the pre-tightening force between the bearing limiting sleeve and the first bearing. According to the scheme, the pre-tightening force of the first bearing is adjusted by adjusting the position of the threaded sleeve relative to the pre-tightening sleeve, that is, the magnitude of the pre-tightening force can be reflected by the relative displacement between the threaded sleeve and the pre-tightening sleeve, and the pre-tightening force of the main shaft bearing can be adjusted without disassembling the electric main shaft.

Description

Technical Field

[0001] The present invention relates to the technical field of preloading of electric spindle bearings, and in particular to a preloading component of an electric spindle, a preloading testing device and an electric spindle. Background Art

[0002] Electric spindles generally use angular contact bearings as supports. Angular contact bearings can bear a certain degree of axial and radial pressure. A certain axial preload must be applied between the inner and outer rings of the angular contact bearing to ensure that the bearing steel balls and the inner and outer ring grooves are in a compressed state and will not fall out of the groove during high-speed rotation.

[0003] The electric spindle runs at high speed and high temperature for a long time. When the processing conditions and process parameters (such as workpiece material, feed speed, grinding depth, etc.) change, the load on the electric spindle shaft end will continue to change. This change will eventually exert force on the spindle bearings. The bearings need to be replaced after being worn under unreasonable working conditions. The preload must be adjusted after replacement and installation. Too little preload will affect the processing accuracy, and too much preload will reduce the service life of the bearings and the electric spindle.

[0004] Currently, after the electric spindle is assembled, the preload force of the spindle bearing cannot be adjusted, and the electric spindle needs to be disassembled and reassembled. Summary of the invention

[0005] The main purpose of the present invention is to provide a preload assembly of an electric spindle, a preload test device and an electric spindle, so as to solve the technical problem that the preload force of the spindle bearing cannot be adjusted after the electric spindle is assembled.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a preload assembly of an electric spindle is provided, comprising: a bearing limit sleeve, which is arranged in the shaft sleeve of the electric spindle; a preload sleeve, which is arranged in the bearing limit sleeve, and a first installation cavity is formed between the preload sleeve and the bearing limit sleeve, and the first installation cavity is used to install a rotor, and the rotor is rotatably connected to the bearing limit sleeve through a first bearing; a threaded sleeve, a part of which is arranged in the preload sleeve, and the threaded sleeve is threadedly connected to the preload sleeve; an elastic member, which is connected between the threaded sleeve and the shaft sleeve; wherein the threaded sleeve can be operated to move along the axial direction of the bearing limit sleeve to adjust the preload force between the bearing limit sleeve and the first bearing.

[0007] Furthermore, an annular protrusion is provided in the inner cavity of the bearing limit sleeve, and a first installation cavity is formed between the annular protrusion and the first end face of the preload sleeve. The annular protrusion is used to abut against the outer ring of the first bearing, and the first end face of the preload sleeve is used to abut against the outer ring of the first bearing. The inner ring of the first bearing is fixedly connected to the rotor.

[0008] Furthermore, the preload assembly also includes: a base, the base is arranged in the shaft sleeve, and a first flange is provided in the cavity of the base; a portion of the threaded sleeve extends into the base, and a second flange is provided at the end of the threaded sleeve away from the preload sleeve, the first end of the elastic member is connected to the first flange, and the second end of the elastic member is connected to the second flange.

[0009] Furthermore, the cavity of the base is arranged to penetrate along the axial direction of the sleeve.

[0010] Furthermore, the outer wall of the threaded sleeve is slidably connected to the first flange.

[0011] Furthermore, the preload assembly also includes: an inner rod, which is arranged in the threaded sleeve; a clamping block, which is arranged at one end of the inner rod close to the first mounting cavity, and the inner rod is abutted against the preload sleeve through the clamping block, and the radial dimension of the clamping block is larger than the inner diameter of the threaded sleeve.

[0012] According to another aspect of the present invention, an electric spindle is provided. The electric spindle includes a pre-tightening assembly, and the pre-tightening assembly is the pre-tightening assembly mentioned above.

[0013] According to another aspect of the present invention, a preload test device for an electric spindle is provided, and the preload test device is used to test the above-mentioned electric spindle, and the preload test device comprises: a support seat, the support seat has a bearing surface for placing the electric spindle; a sensor, the sensor is used to be installed on the end cover of the electric spindle, and the sensor is used to sense the acceleration signal of the electric spindle; a control module, the control module is used to be electrically connected to the electric spindle, and the control module is used to control the rotation of the electric spindle; a monitoring module, the monitoring module and the sensor signal, the monitoring module is used to receive the acceleration signal, and couple the acceleration signal to generate a waveform diagram.

[0014] Furthermore, the preload test device also includes: a support frame, which is connected to the support seat and is arranged above the bearing surface; a fastener, which is movably connected to the support frame, forming a limited space between the fastener and the bearing surface, and adjusting the fastener to move relative to the support frame to change the distance between the fastener and the bearing surface.

[0015] Furthermore, a protective pad is provided at one end of the fastener close to the bearing surface, and the protective pad is used to abut against the electric spindle.

[0016] According to the technical solution of the present invention, the bearing limit sleeve is arranged in the shaft sleeve, the preload sleeve is arranged in the bearing limit sleeve, and a first installation cavity is formed between the preload sleeve and the bearing limit sleeve. The rotor is installed in the first installation cavity through the first bearing, that is, the first bearing is abutted with the preload sleeve and the bearing limit sleeve, the threaded sleeve is threadedly connected to the inner cavity of the preload sleeve, and the threaded sleeve is connected to the shaft sleeve through an elastic member. The threaded sleeve is operated to move along the axial direction of the bearing limit sleeve to compress or stretch the elastic member, so that the elastic force of the elastic member is transmitted to the first bearing through the threaded sleeve, the preload sleeve and the bearing limit sleeve, thereby achieving the purpose of adjusting the preload force of the first bearing. In the above scheme, the preload force of the first bearing is adjusted by adjusting the position of the threaded sleeve relative to the preload sleeve, that is, the relative displacement between the threaded sleeve and the preload sleeve can reflect the size of the preload force, and the preload force of the spindle bearing can be adjusted without disassembling the electric spindle. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 A schematic structural diagram of an embodiment of an electric spindle according to the present invention is shown;

[0019] Figure 2 A structural schematic diagram of an embodiment of a preload test device according to the present invention is shown.

[0020] The above drawings include the following reference numerals:

[0021] 1. Bearing limit sleeve;

[0022] 101, annular protrusion;

[0023] 2. Bushing;

[0024] 3. Preload sleeve;

[0025] 31. Partition;

[0026] 4. Threaded sleeve;

[0027] 401, second flange;

[0028] 5. Elastic parts;

[0029] 6. First bearing;

[0030] 7. Second bearing;

[0031] 8. Base;

[0032] 801, first flange;

[0033] 9. Inner rod;

[0034] 901, compression block;

[0035] 10. Rotor;

[0036] 11. The first limiting ring;

[0037] 12. End cap;

[0038] 13. Second limiting ring;

[0039] 14. The third limiting ring;

[0040] 15. Support seat;

[0041] 16. Support frame;

[0042] 17. Fasteners;

[0043] 18. Protective pad;

[0044] 19. Sensor. DETAILED DESCRIPTION

[0045] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0046] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0047] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0048] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in a variety of different forms and should not be construed as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present application thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art. In the accompanying drawings, for the sake of clarity, the thickness of the layers and regions may be enlarged, and the same reference numerals are used to represent the same devices, and thus their descriptions will be omitted.

[0049] Combination Figure 1 As shown, according to a specific embodiment of the present application, a pretensioning assembly of an electric spindle is provided.

[0050] Specifically, the preload assembly of the electric spindle includes: a bearing limit sleeve 1, a preload sleeve 3, a threaded sleeve 4 and an elastic member 5. The bearing limit sleeve 1 is arranged in the shaft sleeve 2 of the electric spindle, and the preload sleeve 3 is arranged in the bearing limit sleeve 1. A first installation cavity is formed between the preload sleeve 3 and the bearing limit sleeve 1. The first installation cavity is used to install the rotor 10. The rotor 10 is rotatably connected to the bearing limit sleeve 1 through the first bearing 6. Part of the threaded sleeve 4 is arranged in the preload sleeve 3, and the threaded sleeve 4 is threadedly connected to the preload sleeve 3. The elastic member 5 is connected between the threaded sleeve 4 and the shaft sleeve 2, and the threaded sleeve 4 can be operated to move along the axial direction of the bearing limit sleeve 1 to adjust the preload force between the bearing limit sleeve 1 and the first bearing 6.

[0051] In the embodiment of the present application, the bearing limit sleeve 1 is arranged in the shaft sleeve 2, the preload sleeve 3 is arranged in the bearing limit sleeve 1, and a first installation cavity is formed between the preload sleeve 3 and the bearing limit sleeve 1. The rotor 10 is installed in the first installation cavity through the first bearing 6, that is, the first bearing 6 is abutted with the preload sleeve 3 and the bearing limit sleeve 1, the threaded sleeve 4 is threadedly connected with the inner cavity of the preload sleeve 3, and the threaded sleeve 4 is connected with the shaft sleeve 2 through the elastic member 5. The threaded sleeve 4 is operated to move along the axial direction of the bearing limit sleeve 1 to compress or stretch the elastic member 5, so that the elastic force of the elastic member 5 is transmitted to the first bearing 6 through the threaded sleeve 4, the preload sleeve 3 and the bearing limit sleeve 1, thereby achieving the purpose of adjusting the preload force of the first bearing 6. In the above scheme, the preload force of the first bearing 6 is adjusted by adjusting the position of the threaded sleeve 4 relative to the preload sleeve 3, that is, the relative displacement between the threaded sleeve 4 and the preload sleeve 3 can reflect the size of the preload force, and the preload force of the spindle bearing can be adjusted without disassembling the electric spindle.

[0052] Further, the inner cavity of the bearing stop sleeve 1 is provided with an annular protrusion 101, and a first installation cavity is formed between the annular protrusion 101 and the first end face of the preload sleeve 3. The annular protrusion 101 is used to abut against the outer ring of the first bearing 6. The first end face of the preload sleeve 3 is used to abut against the outer ring of the first bearing 6. The inner ring of the first bearing 6 is fixedly connected to the rotor 10. One side of the outer ring of the first bearing 6 abuts against the annular protrusion 101, and the other side abuts against the end face of the preload sleeve 3, so as to realize the connection between the outer ring of the first bearing 6, the preload sleeve 3 and the bearing stop sleeve 1, so that the elastic force of the elastic member 5 is transmitted to the outer ring of the first bearing 6 through the threaded sleeve 4, the preload sleeve 3 and the bearing stop sleeve 1, and the outer ring of the first bearing 6 drives the ball of the first bearing 6 to move, so as to transmit the preload force to the inner ring of the first bearing 6, and then the preload force is applied between the outer ring and the inner ring of the first bearing 6.

[0053] Specifically, Figure 1 As shown, the inner cavity of the bearing limit sleeve 1 is set through along its own axial direction, the bearing limit sleeve 1 is provided with an internal thread, the preload sleeve 3 is provided with an external thread, and the bearing limit sleeve 1 is threadedly connected with the preload sleeve 3. The preload sleeve 3 extends into the inner cavity of the bearing limit sleeve 1 from the first end of the bearing limit sleeve 1 and is threadedly connected with the bearing limit sleeve 1. The second end of the bearing limit sleeve 1 is provided with an annular protrusion 101, and the annular protrusion 101 is arranged around the inner wall of the bearing limit sleeve 1; the inner cavity of the bearing limit sleeve 1 is also provided with an annular step, the inner diameter of the annular step is smaller than the outer diameter of the preload sleeve 3, that is, the preload sleeve 3 abuts against the end face of the annular step, so that a first installation cavity is formed between the first end face of the preload sleeve 3 and the annular protrusion 101, and the length of the first installation cavity is equal to the thickness of the first bearing 6, so that one side of the outer ring of the first bearing 6 abuts against the annular protrusion 101, and the other side of the outer ring of the first bearing 6 abuts against the first end face of the preload sleeve 3.

[0054] Specifically, Figure 1 As shown, the rotor 10 extends into the cavity of the preload sleeve 3 through the first installation cavity, the first bearing 6 is sleeved on the rotor 10, the rotor 10 is a stepped shaft, one side of the inner ring of the first bearing 6 abuts against the shoulder of the rotor 10, and the other side of the inner ring of the first bearing 6 abuts against the first limiting ring 11, wherein the first limiting ring 11 is fixedly connected to the rotor 10.

[0055] Further, the preload assembly further includes a base 8, which is disposed in the shaft sleeve 2, and a first flange 801 is disposed in the cavity of the base 8; a portion of the threaded sleeve 4 extends into the base 8, and a second flange 401 is disposed at one end of the threaded sleeve 4 away from the preload sleeve 3, and a first end of the elastic member 5 is connected to the first flange 801, and a second end of the elastic member 5 is connected to the second flange 401. The elastic member 5 is connected to the shaft sleeve 2 through the base 8, that is, in the process of twisting the threaded sleeve 4, the threaded sleeve 4 moves relative to the base 8, and the magnitude of the preload force can be judged by observing the relative displacement of the threaded sleeve 4 and the base 8.

[0056] Specifically, Figure 1 As shown, the base 8 is used for fixed connection with the shaft sleeve 2. The end of the base 8 close to the preload sleeve 3 is provided with a first flange 801, and the first flange 801 is circumferentially arranged around the inner wall of the base 8. The end of the threaded sleeve 4 away from the preload sleeve 3 is provided with a second flange 401, and the second flange 401 is arranged around the outer circumference of the threaded sleeve 4. Part of the threaded sleeve 4 extends into the base 8, and the second flange 401 is located in the base 8. The elastic member 5 is a spring, and the elastic member 5 is sleeved on the outer wall of the threaded sleeve 4. One end of the elastic member 5 is connected to the first flange 801, and the other end of the elastic member 5 is connected to the second flange 401. The threaded sleeve 4 moves in a direction away from the base 8 to compress the elastic member 5; the threaded sleeve 4 moves in a direction close to the base 8 to release the compression force of the elastic member 5.

[0057] Preferably, the cavity of the base 8 is arranged through the axis of the sleeve 2. After passing through the cavity of the base 8, the tool cooperates with the threaded sleeve 4 to operate the threaded sleeve 4 to move along the axis of the bearing limit sleeve 1, thereby adjusting the preload of the first bearing 6.

[0058] Preferably, the outer wall of the threaded sleeve 4 is slidably connected to the first flange 801. The first flange 801 plays a limiting role, so that the threaded sleeve 4 moves along the axial direction of the bearing limiting sleeve 1, so that the first bearing 6 bears the axial preload.

[0059] Furthermore, the preload assembly further includes: an inner rod 9 and a clamping block 901. The inner rod 9 is disposed in the threaded sleeve 4, and the clamping block 901 is disposed at one end of the inner rod 9 close to the first mounting cavity. The inner rod 9 abuts against the preload sleeve 3 through the clamping block 901, and the radial dimension of the clamping block 901 is greater than the inner diameter of the threaded sleeve 4.

[0060] Preferably, the pressing block 901 and the inner rod 9 are integrally formed.

[0061] Specifically, Figure 1 As shown, the inner cavity of the preload sleeve 3 is provided with a partition 31, and the partition 31 divides the cavity of the preload sleeve 3 into a first chamber and a second chamber. The first chamber is arranged close to the first bearing 6, and part of the rotor 10 extends into the first chamber. The threaded sleeve 4 is located in the second chamber, and the inner rod 9 is inserted into the threaded sleeve 4, and the inner rod 9 abuts against the partition 31 through the clamping block 901. Among them, the partition 31 is provided with a first through hole, and the rotor 10 is inserted into the first through hole and is rotatably connected with the partition 31, the inner rod 9 is provided with a second through hole, and the rotor 10 is provided with a third through hole, and the second through hole and the third through hole are connected along the axial direction of the bearing limit sleeve 1.

[0062] Combination Figure 1 As shown, according to another specific embodiment of the present application, an electric spindle is provided.

[0063] Specifically, the electric spindle comprises: a sleeve 2, a first bearing 6, a second bearing 7, a rotor 10, an end cover 12 and a pre-tightening assembly, wherein the pre-tightening assembly is the pre-tightening assembly in the above embodiment.

[0064] like Figure 1 As shown, the preload assembly, the first bearing 6 and the rotor 10 are all arranged in the cavity of the sleeve 2. A base 8 is provided at one end of the sleeve 2, and an end cover 12 is provided at the other end of the sleeve 2. One end of the rotor 10 is rotatably connected to the preload assembly through the first bearing 6, and the other end of the rotor 10 is rotatably connected to the end cover 12 through the second bearing 7. Specifically, the end cover 12 has an axially through cavity, and one end of the rotor 10 extends to the outside of the sleeve 2 after passing through the end cover 12. A third flange is provided in the inner cavity of the end cover 12, and the third flange is arranged around the inner circumference of the end cover 12. The second bearing 7 is sleeved on the rotor 10; one side of the outer ring of the second bearing 7 abuts against the third flange, and the other side of the outer ring of the second bearing 7 abuts against the second limiting ring 13, wherein the second limiting ring 13 is fixed on the end cover 12; one side of the inner ring of the second bearing 7 abuts against the shaft shoulder of the rotor 10, and the other side of the inner ring of the second bearing 7 abuts against the third limiting ring 14, wherein the third limiting ring 14 is fixed on the rotor 10.

[0065] It should be noted that the preload force applied to the first bearing 6 is transmitted to the second bearing 7 through the rotor 10 , and then the preload force is applied to the first bearing 6 and the second bearing 7 at the same time.

[0066] The disassembly process of the first bearing 6 and the second bearing 7 is as follows:

[0067] 1. Use special tools to unscrew the threaded sleeve 4 and remove the elastic part 5 simultaneously;

[0068] 2. Remove the base 8;

[0069] 3. After the base 8 is removed, unscrew and remove the preload sleeve 3;

[0070] 4. After the preload sleeve 3 is removed, the third limiting ring 14 is removed, and then the second bearing 7, the second limiting ring 13 and the end cover 12 are removed as a whole. By disassembling the second limiting ring 13 and the end cover 12, the second bearing 7 is removed;

[0071] 5. Use special tools to remove the first limiting ring 11;

[0072] 6. Pull the rotor 10 out of the shaft sleeve 2, separate the rotor 10 from the first bearing 6, and take out the first bearing 6.

[0073] After separating and disassembling the electric spindle components, confirm the bearing model to be replaced, clean all parts with alcohol and reinstall them. The installation process of the first bearing 6 and the second bearing 7 is as follows:

[0074] 1. First, insert the rotor 10 into the shaft sleeve 2, with one side extending into the bearing stop sleeve 1, and then install the first bearing 6 on the right side of the rotor 10, so that the left side of the inner ring of the first bearing 6 abuts against the shaft shoulder of the rotor 10, and the left side of the outer ring of the first bearing 6 abuts against the annular protrusion 101 on the bearing stop sleeve 1;

[0075] 2. Install the first limiting ring 11 on the rotor 10 so that the first limiting ring 11 abuts against the right side of the inner ring of the first bearing 6;

[0076] 3. Assemble the second bearing 7, the second limiting ring 13 and the end cover 12, wherein the second limiting ring 13 abuts against the right side of the outer ring of the second bearing 7, and the third flange on the end cover 12 abuts against the left side of the outer ring of the second bearing 7 to form an installation assembly;

[0077] 4. Install the mounting assembly on the shaft sleeve 2, so that the right side of the inner ring of the second bearing 7 abuts against the shaft shoulder of the rotor 10, and then install the third limiting ring 14 on the rotor 10, so that the third limiting ring 14 abuts against the left side of the inner ring of the second bearing 7;

[0078] 5. Install the preload sleeve 3 inside the bearing limit sleeve 1 so that the first end surface of the preload sleeve 3 abuts against the right side of the outer ring of the first bearing 6;

[0079] 6. Install the base 8 on the shaft sleeve 2;

[0080] 7. After the threaded sleeve 4, the elastic member 5 and the inner rod 9 are assembled into a whole, they are screwed into the cavity of the preload sleeve 3 through the inner cavity of the base 8 and are threadedly connected with the preload sleeve 3.

[0081] When the threaded sleeve 4 is tightened, the elastic member 5 is in a compressed state, and the elastic force of the elastic member 5 is transmitted to the first bearing 6 and the second bearing 7 through the threaded sleeve 4, the preload sleeve 3 and the rotor 10, thereby generating a preload force.

[0082] Combination Figure 2 As shown, according to another specific embodiment of the present application, a preload test device for an electric spindle is provided, wherein the preload test device is used to test the electric spindle in the above embodiment.

[0083] Specifically, the preload test device includes: a support seat 15, a sensor 19, a control module and a monitoring module. The support seat 15 has a bearing surface for placing the electric spindle, the sensor 19 is used to be installed on the end cover 12 of the electric spindle, the sensor 19 is used to sense the acceleration signal of the electric spindle, the control module is used to be electrically connected to the electric spindle, the control module is used to control the rotation of the electric spindle, the monitoring module is connected to the sensor 19 signal, and the monitoring module is used to receive the acceleration signal and couple the acceleration signal to generate a waveform diagram.

[0084] In an embodiment of the present application, after the electric spindle is installed, it is fixed on the support seat 15, and the control module is electrically connected to the electric spindle to control the operation of the electric spindle; the acceleration signal of the electric spindle is collected by the sensor 19 and transmitted to the monitoring module, and the monitoring module couples the acceleration signal to generate a waveform diagram, and the waveform diagram is used to feedback whether the preload force of the bearing meets the current speed requirement, thereby guiding the adjustment of the preload force.

[0085] Furthermore, the preload test device further includes: a support frame 16 and a fastener 17. The support frame 16 is connected to the support seat 15, and the support frame 16 is arranged above the bearing surface. The fastener 17 is movably connected to the support frame 16, and a limiting space is formed between the fastener 17 and the bearing surface. The fastener 17 is adjusted to move relative to the support frame 16 to change the distance between the fastener 17 and the bearing surface. The fastener 17 is arranged to clamp the electric spindle to prevent the electric spindle from being separated from the support seat 15 due to vibration, thereby affecting the test of the electric spindle.

[0086] Specifically, Figure 2 As shown, the support frame 16 is a U-shaped frame, the fastener 17 is vertically arranged, and the fastener 17 is threadedly connected to the support frame 16. The distance between the fastener 17 and the bearing surface is adjusted by twisting the fastener 17 to tighten the electric spindle.

[0087] Preferably, the bearing surface is a V-shaped surface to increase the contact area between the bearing surface and the electric spindle.

[0088] Furthermore, a protective pad 18 is provided at one end of the fastener 17 close to the bearing surface, and the protective pad 18 is used to abut against the electric spindle. The protective pad 18 protects the surface of the electric spindle to avoid scratching the surface of the electric spindle.

[0089] It should be noted that the control module may be a CNC machine tool, and the operation of the electric spindle is controlled by the CNC machine tool.

[0090] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0091] 1. In the embodiment of the present application, the bearing limit sleeve 1 is arranged in the shaft sleeve 2, the preload sleeve 3 is arranged in the bearing limit sleeve 1, and a first installation cavity is formed between the preload sleeve 3 and the bearing limit sleeve 1. The rotor 10 is installed in the first installation cavity through the first bearing 6, that is, the first bearing 6 is abutted with the preload sleeve 3 and the bearing limit sleeve 1, the threaded sleeve 4 is threadedly connected with the inner cavity of the preload sleeve 3, and the threaded sleeve 4 is connected with the shaft sleeve 2 through the elastic member 5. The threaded sleeve 4 is operated to move along the axial direction of the bearing limit sleeve 1 to compress or stretch the elastic member 5, so that the elastic force of the elastic member 5 is transmitted to the first bearing 6 through the threaded sleeve 4, the preload sleeve 3 and the bearing limit sleeve 1, thereby achieving the purpose of adjusting the preload force of the first bearing 6. In the above scheme, the preload force of the first bearing 6 is adjusted by adjusting the position of the threaded sleeve 4 relative to the preload sleeve 3, that is, the relative displacement between the threaded sleeve 4 and the preload sleeve 3 can reflect the size of the preload force, and the preload force of the spindle bearing can be adjusted without disassembling the electric spindle.

[0092] 2. In the embodiment of the present application, after the electric spindle is installed, it is fixed on the support seat 15, and the control module is electrically connected to the electric spindle to control the operation of the electric spindle; the acceleration signal of the electric spindle is collected by the sensor 19 and transmitted to the monitoring module, and the monitoring module couples the acceleration signal to generate a waveform diagram, and uses the waveform diagram to feedback whether the preload force of the bearing meets the current speed requirement, thereby guiding the adjustment of the preload force.

[0093] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0094] In addition to the above, it should be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this specification refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when describing a specific feature, structure or characteristic in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of the present invention.

[0095] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A preload assembly for an electric spindle, characterized in that: include: A bearing limiting sleeve (1), wherein the bearing limiting sleeve (1) is arranged inside a shaft sleeve (2) of the electric spindle; A preload sleeve (3), the preload sleeve (3) being arranged in the bearing stop sleeve (1), a first installation cavity being formed between the preload sleeve (3) and the bearing stop sleeve (1), the first installation cavity being used for installing a rotor (10), the rotor (10) being rotatably connected to the bearing stop sleeve (1) via a first bearing (6); A threaded sleeve (4), part of which is arranged inside the preload sleeve (3), and the threaded sleeve (4) is threadedly connected to the preload sleeve (3); An elastic member (5), the elastic member (5) being connected between the threaded sleeve (4) and the shaft sleeve (2); The threaded sleeve (4) can be operated to move along the axial direction of the bearing limiting sleeve (1) to adjust the preload force between the bearing limiting sleeve (1) and the first bearing (6).

2. The preload assembly of the electric spindle according to claim 1, characterized in that: The inner cavity of the bearing limiting sleeve (1) is provided with an annular protrusion (101), and the first installation cavity is formed between the annular protrusion (101) and the first end face of the preload sleeve (3), the annular protrusion (101) is used to abut against the outer ring of the first bearing (6), the first end face of the preload sleeve (3) is used to abut against the outer ring of the first bearing (6), and the inner ring of the first bearing (6) is fixedly connected to the rotor (10).

3. The preload assembly of the electric spindle according to claim 1, characterized in that: The preload assembly also includes: A base (8), the base (8) being arranged in the shaft sleeve (2), and a first flange (801) being arranged in a cavity of the base (8); A portion of the threaded sleeve (4) extends into the base (8), and a second flange (401) is provided at one end of the threaded sleeve (4) away from the preload sleeve (3). The first end of the elastic member (5) is connected to the first flange (801), and the second end of the elastic member (5) is connected to the second flange (401).

4. The preload assembly of the electric spindle according to claim 3, characterized in that: The cavity of the base (8) is arranged to penetrate along the axial direction of the shaft sleeve (2).

5. The preload assembly of the electric spindle according to claim 3, characterized in that: The outer wall of the threaded sleeve (4) is slidably connected to the first flange (801).

6. The preload assembly of the electric spindle according to claim 1, characterized in that: The preload assembly also includes: An inner rod (9), the inner rod (9) being arranged in the threaded sleeve (4); A clamping block (901), wherein the clamping block (901) is arranged at one end of the inner rod (9) close to the first mounting cavity, the inner rod (9) abuts against the preload sleeve (3) through the clamping block (901), and the radial dimension of the clamping block (901) is greater than the inner diameter of the threaded sleeve (4).

7. An electric spindle, comprising a preload assembly, characterized in that: The pre-tightening assembly is the pre-tightening assembly according to any one of claims 1 to 6.

8. A preload test device for an electric spindle, the preload test device being used to test the electric spindle as claimed in claim 7, characterized in that: The preload test device comprises: A support seat (15), wherein the support seat (15) has a bearing surface for placing the electric spindle; A sensor (19), the sensor (19) being used to be mounted on an end cover (12) of the electric spindle, and the sensor (19) being used to sense an acceleration signal of the electric spindle; A control module, the control module is used to be electrically connected to the electric spindle, and the control module is used to control the rotation of the electric spindle; A monitoring module is connected to the sensor (19) signal, and the monitoring module is used to receive the acceleration signal and couple the acceleration signal to generate a waveform diagram.

9. The preload test device according to claim 8, characterized in that: The preload test device also includes: A support frame (16), the support frame (16) is connected to the support seat (15), and the support frame (16) is arranged above the bearing surface; A fastener (17), wherein the fastener (17) is movably connected to the support frame (16), a limiting space is formed between the fastener (17) and the bearing surface, and the fastener (17) is adjusted to move relative to the support frame (16) to change the distance between the fastener (17) and the bearing surface.

10. The preload test device according to claim 9, characterized in that: A protection pad (18) is provided at one end of the fastener (17) close to the bearing surface, and the protection pad (18) is used to abut against the electric spindle.

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