Static pressure spindle unit end face run-out measuring equipment and measuring method
Through the end face jump measurement equipment of the static pressure spindle unit, the jump error of the end face bearing is measured using liquid plastic channels and displacement sensors, and through scraping or grinding adjustment, the problem of insufficient assembly accuracy of the static pressure spindle unit is solved, achieving higher assembly and working accuracy.
Patent Information
- Application Number
- CN202411305283.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2024-12-20
AI Technical Summary
The existing static spindle units are difficult to achieve ultra-precision level (HP1 or HP0) accuracy during assembly, mainly due to the insufficient accuracy of the front bearings of static pressure, rear bearings and body shell components, especially the end-side static pressure annular oil chamber. The planetary and verticality errors are large, which affects the assembly accuracy.
Provided is a static pressure spindle unit end face jump measuring equipment, including a centering device, a measuring device and a support device, which measures and adjusts the jump error of the end face bearing through a liquid plastic channel and a displacement sensor measuring mechanism, and reduces it by scraping or grinding methods. Error, improve assembly accuracy.
By accurately measuring and adjusting the jumping error of the end face bearing, the assembly accuracy and working accuracy of the static pressure spindle unit are improved, and manufacturing costs are reduced.
Smart Images
Figure CN119164340A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of hydrostatic spindle units, and in particular to a hydrostatic spindle unit end face runout measuring device and a measuring method. Background Art
[0002] The hydrostatic spindle unit is a spindle unit that uses liquid hydrostatic bearings as support. The hydrostatic spindle unit is generally radially supported by a hydrostatic front bearing and a hydrostatic rear bearing, and a thrust bearing is formed by an end bearing. According to the different settings of the end bearing, the hydrostatic spindle unit can be roughly divided into two structures. The first hydrostatic spindle unit structure is to open a hydrostatic annular oil chamber on both side end faces of the hydrostatic front bearing or the hydrostatic rear bearing, and then use the spindle shoulder and the thrust ring sleeved on the spindle to abut against both sides of the bearing where the hydrostatic annular oil chamber is opened to form an end bearing by the hydrostatic annular oil chambers on both sides. The adjustment of the oil film thickness of the end bearing is achieved by moving the position of the thrust ring along the axis of the spindle from the inside of the hydrostatic spindle unit body shell. The second hydrostatic spindle unit structure is to select a bearing from the hydrostatic front bearing and the hydrostatic rear bearing, set a first annular hydrostatic oil chamber on the outer end face of the bearing, and then set a bearing cover part, open a second annular hydrostatic oil chamber on one end face of the bearing cover, and use the shaft ring set on the main shaft to install the first annular hydrostatic oil chamber and the second annular hydrostatic oil chamber on both sides of the shaft ring to form a thrust structure of the end face bearing. The hydrostatic front bearing, hydrostatic rear bearing and body shell of this type of hydrostatic spindle unit structure can be assembled into a component, as shown in the attached Figure 1 As shown in the figure, the housing 101, the front static pressure bearing 102 and the rear static pressure bearing 103 can be assembled into an assembly, a shaft collar 110 is arranged on the main shaft 105, a first annular static pressure oil chamber 111 and a second annular static pressure oil chamber 112 are respectively arranged on the front static pressure bearing 102 and the bearing cover 104, the first annular static pressure oil chamber 111 and the second annular static pressure oil chamber 112 are arranged relative to the two sides of the shaft collar 110, and the distance between the first annular static pressure oil chamber 111 and the second annular static pressure oil chamber 112 is adjusted by the thickness of the spacer 106 arranged outside the shaft collar 110, at this time, the front static pressure bearing 102 and the bearing cover 104 form an end bearing, and the front bearing static pressure acting cylinder 107 and the rear bearing static pressure acting cylinder 108 of the front static pressure bearing 102 and the rear static pressure bearing 103 form a radial bearing.
[0003] According to the standard JB / T 11767-2014 "Hydrostatic, Hydrostatic and Dynamic Bearing Spindle Unit", the accuracy level of hydrostatic spindle units is divided into five levels: ordinary level (HP4), precision level (HP3), high precision level (HP2), ultra-precision level (HP1) and ultra-high precision level (HP0). The higher the accuracy level, the higher the machining accuracy requirements for each part during the assembly process, and the corresponding requirements for the measuring tools are also put forward. In the first hydrostatic spindle unit structure, it is necessary to move the thrust ring from the inside of the spindle unit body shell along the spindle axis to adjust the oil film thickness. When it is found that the assembly accuracy of the spindle unit is caused by the hydrostatic bearing with two end surface hydrostatic annular oil chambers, it is generally necessary to remove the bearing from the body shell and adjust its machining accuracy. Since the bearing and the body shell need to be re-installed and positioned, its assembly accuracy is affected; if the ultra-precision level (HP1) or ultra-high precision level (HP0) is to be achieved, the machining accuracy of the bearing, body shell and thrust ring and other parts needs to be set to a particularly high level, which is obviously not conducive to reducing the manufacturing cost of the hydrostatic spindle unit. The bearing cover of the second type of hydrostatic spindle unit structure is a separate part, and its processing accuracy is easy to ensure. There are many methods to improve the assembly accuracy. The remaining problem is how to improve the accuracy of the assembly formed by the hydrostatic front bearing, the hydrostatic rear bearing and the body shell; the hydrostatic front bearing, the hydrostatic rear bearing and the body shell are assembled into an assembly after their respective processing is completed. The inner hole formed by the hydrostatic front bearing and the hydrostatic rear bearing can be ground to improve the coaxiality of the inner holes of the two bearings. At this time, to improve the accuracy of the hydrostatic spindle unit bearing assembly, it is necessary to improve the flatness of the bearing end face with the end face hydrostatic annular oil cavity and the verticality of the bearing hole adjacent to it. At this time, it is necessary to measure the runout error of the bearing end face surface with the end face hydrostatic annular oil cavity, so as to adopt scraping, grinding and other methods to reduce the flatness and verticality errors, and finally improve the assembly accuracy of the entire hydrostatic spindle unit.
[0004] In order to improve the working accuracy of the second hydrostatic spindle unit, it is necessary to provide a measuring instrument for measuring the assembly of the hydrostatic front bearing, the hydrostatic rear bearing and the body shell according to its structure during the assembly process, and use the measuring instrument to reduce the flatness and verticality errors of the bearing end face. Summary of the invention
[0005] The purpose of the present invention is to address the gaps in the prior art and to provide a hydrostatic spindle unit end face runout measurement device and method. According to the size and position of the total runout error, the total runout error of the hydrostatic action surface of the end face bearing is reduced by scraping or grinding, thereby ultimately improving the assembly accuracy of the hydrostatic spindle unit.
[0006] To achieve the above-mentioned purpose, the present invention provides a hydrostatic spindle unit end face runout measurement equipment, including a centering device, a measuring device and a supporting device, wherein the supporting device is arranged at the lower part of the hydrostatic spindle unit, the centering device is installed at the top of the supporting device, and is movably connected to the inner hole of the bearing assembly arranged on the inner side of the hydrostatic spindle unit, so as to form a circumferential positioning for the bearing assembly of the hydrostatic spindle unit in the radial direction; the measuring device is rotatably connected to the top of the centering device, so as to realize the measurement of the runout error of the hydrostatic action surface of the end face bearing of the bearing assembly of the hydrostatic spindle unit.
[0007] Furthermore, the centering device includes: a centering shaft, a first thin-walled sleeve and a second thin-walled sleeve, wherein the first thin-walled sleeve and the second thin-walled sleeve are respectively sleeved on the lower end and the upper end of the centering shaft; a first liquid plastic channel is provided between the centering shaft and the first thin-walled sleeve, and a second liquid plastic channel is provided between the centering shaft and the second thin-walled sleeve; a first liquid plastic input channel and a first liquid plastic output channel leading to the first liquid plastic channel are provided on the lower end surface of the centering shaft, and a first pressure screw and a first pressure screw are placed in the first liquid plastic input channel from the outside to the inside. A first sliding column, a first plug is provided on the opening of the first liquid plastic output channel; a second liquid plastic input channel and a second liquid plastic output channel leading to the second liquid plastic channel are provided on the upper end surface of the centering shaft, a second pressure screw and a second sliding column are placed in the second liquid plastic input channel from the outside to the inside, and a second plug is provided on the opening of the second liquid plastic output channel; the first liquid plastic channel between the first thin-walled sleeve and the centering shaft is filled with liquid plastic; the second liquid plastic channel between the second thin-walled sleeve and the centering shaft is filled with liquid plastic.
[0008] Furthermore, a handle is provided below the first pressurizing screw and above the second pressurizing screw.
[0009] Furthermore, the measuring device includes: a composite bearing, a first spacer, a slewing bracket, a second spacer, a locking nut, a bearing sleeve, a pressure cover and a displacement sensor measuring mechanism, a shoulder is arranged at the upper end of the centering shaft, the first spacer, the inner ring of the composite bearing and the second spacer are sequentially mounted on the centering shaft from bottom to top, and the uppermost end is locked downward by the locking nut so that the lower end surface of the first spacer is against the shoulder end surface of the centering shaft; a slewing bracket is arranged outside the outer ring of the composite bearing, a bearing sleeve and a pressure cover are sequentially installed above the slewing bracket, and the pressure cover and the slewing bracket are connected by screws to realize axial positioning of the composite bearing; a displacement sensor measuring mechanism is installed on the outer side wall of the slewing bracket, and a displacement sensor is arranged inside the displacement sensor measuring mechanism.
[0010] Furthermore, the displacement sensor measuring mechanism includes a guide rail crossbeam, an upper plate, a lower plate, a first upper bearing support assembly, a second upper bearing support assembly, a first bearing support assembly in the vertical direction, a second bearing support assembly in the vertical direction, a third bearing support assembly in the vertical direction, a fourth bearing support assembly in the vertical direction, a first lower bearing support assembly and a second lower bearing support assembly; the guide rail crossbeam is arranged on the outside of the slewing bracket, and its guide rail direction is perpendicular to the slewing centerline OO of the composite bearing; the first upper bearing support assembly and the second upper bearing support assembly are installed on the upper plate one inside and one outside; the first lower bearing support assembly and the second lower bearing support assembly are installed on the lower plate one inside and one outside; a sensor bracket is provided on one side of the lower plate; the second bearing support assembly in the vertical direction, the third bearing support assembly in the vertical direction and the first bearing support assembly in the vertical direction and the fourth bearing support assembly in the vertical direction are respectively arranged on both sides of the guide rail crossbeam one inside and one outside; the first bearing support assembly in the vertical direction, the second bearing support assembly in the vertical direction, the third bearing support assembly in the vertical direction and the fourth bearing support assembly in the vertical direction are respectively connected to the upper plate and the lower plate at both ends, and springs are provided inside.
[0011] Furthermore, the measuring device also includes a worm wheel, a worm, a box seat and a motor. The worm wheel is arranged between the bearing sleeve and the pressure cover above the rotating support. The box seat is installed on the upper end surface of the body shell of the hydrostatic spindle unit. The worm is supported in the side wall hole of the box seat by a rolling bearing. One end of the worm is externally provided with a motor and is fixedly connected to the output shaft of the motor, and the worm is meshed with the worm wheel.
[0012] Furthermore, the displacement sensor measuring mechanism also includes a clamping mechanism and a positioning device, two positioning devices are provided on one side of the upper plate, and a clamping mechanism is provided on the other side of the upper plate.
[0013] Furthermore, the support device includes a shaft support seat and a body shell support seat, the shaft support seat is installed on the body shell support seat; the shaft support seat is arranged below the centering shaft, and the body shell support seat is arranged below the body shell of the hydrostatic spindle unit.
[0014] A method for measuring end face runout of a hydrostatic spindle unit comprises the following steps:
[0015] S1: The hydrostatic front bearing, the hydrostatic rear bearing and the body shell of the hydrostatic spindle unit are assembled into an assembly;
[0016] S2: grinding the static pressure acting cylinder of the front static pressure front bearing and the static pressure acting cylinder of the rear static pressure rear bearing in step S1 by a grinding rod to improve the coaxiality of the two holes of the static pressure acting cylinder of the front bearing and the static pressure acting cylinder of the rear bearing;
[0017] S3: Place the assembly completed in step S2 in the vertical direction so that the end face of the static pressure front bearing faces upward, place a support device under the body shell, and adjust the support device so that the assembly is placed stably;
[0018] S4: Place the centering device of the end face runout measurement equipment into the hydrostatic front bearing and the hydrostatic rear bearing of the hydrostatic spindle unit from top to bottom, and adjust the shaft support seat of the support device at the lower end of the centering device to form a stable support for the centering device;
[0019] S5: Rotate the first pressure screw and the second pressure screw of the centering device respectively, so that the liquid plastic in the first liquid plastic channel and the second liquid plastic channel forces the first thin-walled sleeve and the second thin-walled sleeve to expand radially and respectively abut against the static pressure action cylinder surface of the rear bearing and the static pressure action cylinder surface of the front bearing, so that the centering device is fixedly connected with the static pressure front bearing and the static pressure rear bearing, thereby realizing radial circumferential positioning of the static pressure front bearing and the static pressure rear bearing;
[0020] S6: Install the measuring device and adjust the distance between the displacement sensor and the static pressure action surface of the end face bearing so that the displacement sensor can sense the distance signal between the displacement sensor and the static pressure action surface of the end face bearing;
[0021] S7: Manually rotate the slewing bracket of the measuring device to make the guide rail crossbeam rotate around the slewing center line OO of the composite bearing, and record the displacement signal measured by the displacement sensor at each rotation of the slewing bracket;
[0022] S8: changing the radial position of the guide rail motion mechanism where the upper plate of the displacement sensor measuring mechanism of the measuring device is located on the guide rail crossbeam relative to the composite bearing, and recording the displacement signal of the displacement sensor according to step S7; after multiple cycles, the measurement is completed, and the end face runout measurement equipment is taken out from the hydrostatic spindle unit;
[0023] S9: using a data analysis system to process the displacement signals measured in steps S7 and S8 to obtain the end face total runout error of the static pressure action surface of the end face bearing;
[0024] S10: according to the total runout error of the end surface of the end bearing static pressure action surface in step S9, reducing the total runout error by scraping or grinding;
[0025] S11: Measure the total runout error of the end face of the static pressure action surface of the end face bearing again according to steps S7 to S9. If the total runout error of the end face does not meet the assembly accuracy requirement, implement step S10 until the accuracy requirement is met.
[0026] Further, step S7 is replaced by: S7': driven by the motor, under the transmission action of the worm wheel and the worm, the slewing bracket rotates, so that the guide rail beam rotates around the composite bearing rotation center line OO, and the displacement signal measured by the displacement sensor at each rotation of the slewing bracket is recorded.
[0027] The beneficial effects of the present invention are:
[0028] The present invention squeezes the liquid plastic in the centering shaft of the centering device so that the first thin-walled sleeve and the second thin-walled sleeve arranged outside the centering shaft expand radially. After the first thin-walled sleeve and the second thin-walled sleeve expand radially, they abut against the radial hydrostatic bearing action surfaces of the hydrostatic rear bearing and the hydrostatic front bearing. Under the action of a certain pressure, the liquid plastic fixes the first thin-walled sleeve and the second thin-walled sleeve to the hydrostatic rear bearing and the hydrostatic front bearing, thereby forming a circumferential positioning for the hydrostatic spindle unit bearing assembly in the radial direction. Then, a slewing bracket arranged outside the composite bearing in the measuring device is used, and the rotation of the slewing bracket drives the displacement sensor measuring mechanism on the guide rail crossbeam to rotate, and the displacement sensor arranged in the displacement sensor measuring mechanism is used to measure the runout error of the hydrostatic action surface of the end face bearing. During the assembly process, the position with larger error is found out according to the total runout error data obtained by measurement. The total runout error of the static pressure action surface of the end bearing can be reduced by scraping or grinding, so that the accuracy of the bearing assembly of the static pressure spindle unit is improved, and finally the assembly accuracy of the entire static pressure spindle unit is improved to improve the working accuracy of the static pressure spindle unit. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 This is the second type of static pressure spindle unit structure that the present invention is mainly aimed at;
[0030] Figure 2 It is a main cross-sectional view of a static pressure spindle unit end face runout measurement device of the present invention;
[0031] Figure 3 It is a right view of a hydrostatic spindle unit end face runout measurement device of the present invention;
[0032] Figure 4 It is a partial three-dimensional first view of a static pressure spindle unit end face runout measurement device of the present invention;
[0033] Figure 5 The present invention is a partial stereoscopic second view of a hydrostatic spindle unit end face runout measurement device.
[0034] Among them, in the figure:
[0035] 1-Hydrostatic spindle unit; 101-housing; 102-Hydrostatic front bearing; 103-Hydrostatic rear bearing; 104-bearing cover; 105-spindle; 106-spacer; 107-Hydrostatic cylinder of front bearing; 108-Hydrostatic cylinder of rear bearing; 109-Hydrostatic surface of end bearing; 110-shaft ring; 111-first annular hydrostatic oil chamber; 112-second annular hydrostatic oil chamber; 2-centering device ;201-centering shaft;202-first pressure screw;203-first screw plug;204-first slide column;205-first thin-walled sleeve;206-first liquid plastic channel;210-second thin-walled sleeve;211-second liquid plastic channel;213-second screw plug;214-second pressure screw;215-second slide column;3-measuring device;301-first spacer;302-swivel bracket; 303-composite bearing; 304-bearing sleeve; 305-worm gear; 306-pressure cover; 307-second spacer sleeve; 308-locking nut; 309-worm; 310-box seat; 311-guide rail beam; 312-motor; 313-first bearing support assembly in vertical direction; 314-upper plate; 315-first upper bearing support assembly; 316-second bearing support assembly in vertical direction; 317-sensor bracket; 318-lower plate; 319-second upper bearing support assembly; 320-clamping mechanism; 321-third bearing support assembly in vertical direction; 322-fourth bearing support assembly in vertical direction; 323-positioning device; 324-first lower bearing support assembly; 325-second lower bearing support assembly; 326-displacement sensor; 4-support device; 401-shaft support seat; 402-shell support seat. DETAILED DESCRIPTION
[0036] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0037] 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 sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. 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 comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0038] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.
[0039] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.
[0040] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0041] like Figure 1-5 As shown, the present invention provides a hydrostatic spindle unit end face runout measurement equipment, comprising a centering device 2, a measuring device 3 and a supporting device 4, wherein the supporting device 4 is arranged at the lower part of the hydrostatic spindle unit 1, the centering device 2 is installed at the top end of the supporting device 4, and is movably connected to the two bearing inner holes of the bearing assembly arranged on the inner side of the hydrostatic spindle unit 1, so as to form a circumferential positioning for the bearing assembly of the hydrostatic spindle unit 1 in the radial direction; the measuring device 3 is rotatably connected to the top end of the centering device 2, so as to realize the measurement of the runout error of the hydrostatic action surface 109 of the end face bearing of the bearing assembly of the hydrostatic spindle unit 1.
[0042] The centering device 2 includes: a centering shaft 201, a first thin-walled sleeve 205 and a second thin-walled sleeve 210, wherein the first thin-walled sleeve 205 and the second thin-walled sleeve 210 are respectively sleeved on the lower end and the upper end of the centering shaft 201; the positions of the first thin-walled sleeve 205 and the second thin-walled sleeve 210 on the centering shaft 201 are adjusted according to the positions of the hydrostatic front bearing 102 and the hydrostatic rear bearing 103 in the hydrostatic spindle unit 1, so that the outer cylindrical surfaces of the first thin-walled sleeve 205 and the second thin-walled sleeve 210 are adapted to the rear bearing hydrostatic action cylinder 108 and the front bearing hydrostatic action cylinder 107 of the hydrostatic rear bearing 103 and the hydrostatic front bearing 102. A first liquid plastic channel 206 is provided between the centering shaft 201 and the first thin-walled sleeve 205, and a second liquid plastic channel 211 is provided between the centering shaft 201 and the second thin-walled sleeve 210; a first liquid plastic input channel and a first liquid plastic output channel leading to the first liquid plastic channel 206 are provided on the lower end surface of the centering shaft 201, a first pressurizing screw 202 and a first sliding column 204 are placed in the first liquid plastic input channel from the outside to the inside, and a first screw plug 203 is provided on the opening of the first liquid plastic output channel; the first liquid plastic channel 206 between the first thin-walled sleeve 205 and the centering shaft 201 is filled with liquid plastic; when the first pressurizing screw 202 is rotated to enter the first liquid plastic input channel, the first pressurizing screw 202 pushes the first sliding column 204 to move upward, so that the first sliding column 204 forces the liquid plastic in the first liquid plastic channel 206 to push the first thin wall of the middle section of the first thin-walled sleeve 205 to expand radially. A second liquid plastic input channel and a second liquid plastic output channel leading to the second liquid plastic channel 211 are provided on the upper end surface of the centering shaft 201. A second pressure screw 214 and a second slide column 215 are placed in the second liquid plastic input channel from the outside to the inside, and a second plug 213 is provided on the opening of the second liquid plastic output channel; the second liquid plastic channel 211 between the second thin-walled sleeve 210 and the centering shaft 201 is filled with liquid plastic; when the second pressure screw 214 is rotated to enter the second liquid plastic input channel, the second pressure screw 214 pushes the second slide column 215 to move downward, so that the second slide column 215 forces the liquid plastic in the second liquid plastic channel 211 to push the second thin wall of the middle section of the second thin-walled sleeve 210 to expand radially. By squeezing the liquid plastic in the centering shaft 201 of the centering device 2, the first thin-walled sleeve 205 and the second thin-walled sleeve 210 arranged outside the centering shaft 201 are radially expanded. After the first thin-walled sleeve 205 and the second thin-walled sleeve 210 are radially expanded, they abut against the rear bearing static pressure action cylinder 108 of the static pressure rear bearing 103 and the front bearing static pressure action cylinder 107 of the static pressure front bearing 102. Under the action of a certain pressure of the liquid plastic, the first thin-walled sleeve 205 and the second thin-walled sleeve 210 are fixedly connected with the static pressure rear bearing 103 and the static pressure front bearing 102, forming a circumferential positioning for the bearing assembly of the static pressure spindle unit 1 in the radial direction.
[0043] To further optimize the technical solution, handles are provided below the first pressure screw 202 and above the second pressure screw 214 to facilitate screwing the first pressure screw 202 and the second pressure screw 214 in and out, thus saving effort.
[0044] The measuring device 3 comprises: a composite bearing 303, a first spacer 301, a slewing bracket 302, a second spacer 307, a locking nut 308, a bearing sleeve 304, a pressure cover 306 and a displacement sensor measuring mechanism. A shoulder is arranged at the upper end of the centering shaft 201. The first spacer 301, the inner ring of the composite bearing 303 and the second spacer 307 are sequentially arranged on the centering shaft 201 from bottom to top. The upper end is locked downward by the locking nut 308 to realize the first spacer. The lower end face of the sleeve 301 abuts against the shoulder end face of the centering shaft 201; a slewing bracket 302 is arranged on the outer ring of the composite bearing 303, a bearing sleeve 304 and a pressure cover 306 are sequentially installed above the slewing bracket 302, and the pressure cover 306 and the slewing bracket 302 are connected by screws to realize the axial positioning of the composite bearing 303; a displacement sensor measuring mechanism is installed on the outer wall of the slewing bracket 302, and a displacement sensor 326 is arranged inside the displacement sensor measuring mechanism. The slewing bracket 302 can rotate around the rotation center line OO of the composite bearing 303 through the composite bearing 303, so that the displacement sensor 326 on the displacement sensor measuring mechanism also rotates, so as to realize the measurement of the runout error of the end face bearing static pressure action surface 109 of the static pressure front bearing 102 of the static pressure spindle unit 1. The composite bearing 303 can withstand radial loads and axial loads. The displacement sensor 326 is preferably a non-contact displacement sensor.
[0045] The displacement sensor measuring mechanism includes a guide rail beam 311, an upper plate 314, a lower plate 318, a first upper bearing support assembly 315, a second upper bearing support assembly 319, a first vertical bearing support assembly 313, a second vertical bearing support assembly 316, a third vertical bearing support assembly 321, a fourth vertical bearing support assembly 322, a first lower bearing support assembly 324 and a second lower bearing support assembly 325; the guide rail beam 311 is arranged on the outside of the slewing bracket 302, and its guide rail direction is perpendicular to the slewing centerline OO of the composite bearing 303; the upper The first upper bearing support assembly 315 and the second upper bearing support assembly 319 are installed inside and outside the plate 314; the first lower bearing support assembly 324 and the second lower bearing support assembly 325 are installed inside and outside the lower plate 318; a sensor bracket 317 is provided on one side of the lower plate 318; the second vertical bearing support assembly 316, the third vertical bearing support assembly 321 and the first vertical bearing support assembly 313 and the fourth vertical bearing support assembly 322 are respectively provided on both sides of the guide rail crossbeam 311, inside and outside; the first vertical bearing support assembly 313, the vertical direction The second bearing support assembly 316, the third vertical bearing support assembly 321 and the fourth vertical bearing support assembly 322 are detachably connected to the upper plate 314 and the lower plate 318 at both ends, and springs are arranged inside. The spring force can be adjusted by nuts arranged on the upper ends of the first vertical bearing support assembly 313, the second vertical bearing support assembly 316, the third vertical bearing support assembly 321 and the fourth vertical bearing support assembly 322, so as to realize the first upper bearing support assembly 315, the second upper bearing support assembly 319, the third vertical bearing support assembly 321 and the fourth vertical bearing support assembly 322 installed on the upper plate 314 and the lower plate 318. The pressing force between the lower bearing support assembly 324 and the second lower bearing support assembly 325 and the upper and lower surfaces of the guide rail beam 311 is finally formed by the first vertical bearing support assembly 313, the second vertical bearing support assembly 316, the third vertical bearing support assembly 321, the fourth vertical bearing support assembly 322, the first upper bearing support assembly 315, the second upper bearing support assembly 319, the first lower bearing support assembly 324, the second lower bearing support assembly 325 and the upper plate 314 and the lower plate 318 surrounding the guide rail beam 311 to form a guide rail motion mechanism of the displacement sensor measurement mechanism. By adjusting the radial position of the guide rail motion mechanism along the guide rail beam 311 relative to the composite bearing 303, the displacement sensor 326 can measure the runout error at different radii of the end face bearing static pressure action surface 109 of the static pressure front bearing 102 of the static pressure spindle unit 1 to obtain the total runout error.
[0046] In another embodiment, the measuring device 3 also includes a worm gear 305, a worm 309, a box seat 310 and a motor 312. The worm gear 305 is arranged between the bearing sleeve 304 and the pressure cover 306 above the rotating support 302. The box seat 310 is installed on the upper end surface of the body shell 101 of the hydrostatic spindle unit 1. The worm 309 is supported in the side wall hole of the box seat 310 by a rolling bearing. One end of the worm 309 is externally provided with a motor 312 and is fixedly connected to the output shaft of the motor 312, and the worm 309 is meshed with the worm gear 305. Under the driving action of the motor 312, the slewing bracket 302 and the guide rail beam 311 can be driven to slew around the slewing center line OO of the composite bearing 303 through the meshing transmission of the worm wheel 305 and the worm 309. At this time, the slewing center line OO is also the slewing center line of the hydrostatic spindle unit 1. The displacement sensor 326 on the guide rail beam 311 can measure the runout error of the end face bearing hydrostatic action surface 109 of the hydrostatic front bearing 102 of the hydrostatic spindle unit 1. By adjusting the radial position of the guide rail motion mechanism along the guide rail beam 311 relative to the composite bearing 303, the displacement sensor 326 can measure the runout error of the end face bearing hydrostatic action surface 109 of the hydrostatic front bearing 102 of the hydrostatic spindle unit 1 at different radii to obtain the total runout error.
[0047] In another embodiment, the displacement sensor measuring mechanism further includes a clamping mechanism 320 and a positioning device 323, two positioning devices 323 are provided on one side of the upper plate 314, and a clamping mechanism 320 is provided on the other side of the upper plate 314. After changing the radial position of the guide rail motion mechanism where the upper plate 314 and the lower plate 318 are located along the guide rail crossbeam 311 relative to the composite bearing 303, the upper plate 314 and the lower plate 318 are fixedly connected to the guide rail crossbeam 311 through the clamping mechanism 320 and the positioning device 323, so that the radial position of the displacement sensor 326 relative to the rotation centerline OO of the hydrostatic spindle unit 1 can be changed, and a radial displacement sensor is provided on the guide rail crossbeam 311 to record the change of displacement. Each time the radial position of the displacement sensor 326 is changed, the displacement data measured by the displacement sensor 326 is recorded, so that the total runout error of the hydrostatic action surface 109 of the end bearing of the hydrostatic front bearing 102 is measured by the displacement sensor 326 and the radial displacement sensor.
[0048] The support device includes a shaft support seat 401 and a body shell support seat 402, the shaft support seat 401 is installed on the body shell support seat 402; the shaft support seat 401 is arranged below the centering shaft 201, and the body shell support seat 402 is arranged below the body shell 101 of the hydrostatic spindle unit 1.
[0049] The present invention also provides a method for measuring the end face runout of a hydrostatic spindle unit, comprising the following steps:
[0050] S1: The hydrostatic front bearing 102, the hydrostatic rear bearing 103 and the body shell 101 of the hydrostatic spindle unit 1 are assembled into an assembly;
[0051] S2: grinding the front bearing static pressure action cylinder 107 of the static pressure front bearing 102 and the rear bearing static pressure action cylinder 108 of the static pressure rear bearing 103 in step S1 by a grinding rod to improve the coaxiality of the two holes of the front bearing static pressure action cylinder 107 and the rear bearing static pressure action cylinder 108;
[0052] S3: Place the assembly completed in step S2 in the vertical direction so that the end bearing static pressure action surface 109 of the static pressure front bearing 102 faces upward, place the support device 4 below the body shell 101, and adjust the support device 4 so that the assembly is placed stably;
[0053] S4: Place the centering device 2 of the end face runout measurement equipment into the hydrostatic front bearing 102 and the hydrostatic rear bearing 103 of the hydrostatic spindle unit 1 from top to bottom, and adjust the shaft support seat 401 of the support device 4 at the lower end of the centering device 2 to form a stable support for the centering device 2;
[0054] S5: Rotate the first pressurizing screw 202 and the second pressurizing screw 214 of the centering device 2 respectively, so that the liquid plastic in the first liquid plastic channel 206 and the second liquid plastic channel 211 forces the first thin-walled sleeve 205 and the second thin-walled sleeve 210 to expand radially and abut against the static pressure acting cylinder 108 of the rear bearing and the static pressure acting cylinder 107 of the front bearing respectively, so that the centering device 2 is fixedly connected with the static pressure front bearing 102 and the static pressure rear bearing 103, thereby realizing radial circumferential positioning of the static pressure front bearing 102 and the static pressure rear bearing 103;
[0055] S6: Install the measuring device 3, and adjust the distance between the displacement sensor 326 and the static pressure action surface 109 of the end bearing, so that the displacement sensor 326 can sense the distance signal between the displacement sensor 326 and the static pressure action surface 109 of the end bearing;
[0056] S7: Manually rotate the swivel bracket 302 of the measuring device 3 to make the guide rail crossbeam 311 rotate around the swivel center line OO of the composite bearing 303, and record the displacement signal measured by the displacement sensor 326 at each rotation of the swivel bracket 302;
[0057] S8: changing the radial position of the guide rail motion mechanism where the upper plate 314 of the displacement sensor measuring mechanism of the measuring device 3 is located on the guide rail crossbeam 311 relative to the composite bearing 303, and recording the displacement signal of the displacement sensor 326 according to step S7; after multiple cycles, the measurement is completed, and the end face runout measurement equipment is taken out from the hydrostatic spindle unit 1;
[0058] S9: using a data analysis system to process the displacement signals measured in steps S7 and S8 to obtain the end face total runout error of the static pressure action surface 109 of the end face bearing;
[0059] S10: according to the total runout error of the end surface of the end bearing static pressure action surface 109 in step S9, reducing the total runout error by scraping or grinding;
[0060] S11: Measure the end face total runout error of the end face bearing static pressure action surface 109 again according to steps S7 to S9. If the end face total runout error does not meet the assembly accuracy requirement, implement step S10 until the accuracy requirement is met.
[0061] To further optimize the technical solution, step S7 is replaced by: S7': driven by the motor 312, under the transmission action of the worm wheel 305 and the worm 309, the swivel bracket 302 rotates, so that the guide rail beam 311 rotates around the rotation center line OO of the composite bearing 303, and the displacement signal measured by the displacement sensor 326 at each rotation of the swivel bracket 302 is recorded.
[0062] The present invention squeezes the liquid plastic in the centering shaft of the centering device so that the first thin-walled sleeve and the second thin-walled sleeve arranged outside the centering shaft expand radially. After the first thin-walled sleeve and the second thin-walled sleeve expand radially, they abut against the radial static pressure bearing action surfaces of the static pressure rear bearing and the static pressure front bearing. Under the action of a certain pressure, the liquid plastic fixes the first thin-walled sleeve and the second thin-walled sleeve to the static pressure rear bearing and the static pressure front bearing, thereby positioning the bearing assembly of the static pressure spindle unit in the radial direction. Then, a rotating bracket arranged outside the composite bearing in the measuring device is used, and the rotation of the rotating bracket drives the displacement sensor measuring mechanism on the guide rail crossbeam to rotate, and the runout error of the static pressure action surface of the end face bearing is measured by the internal displacement sensor. During the assembly process, the position with larger error is found out according to the total runout error data obtained by measurement. The total runout error of the static pressure action surface of the end bearing can be reduced by scraping or grinding, so that the accuracy of the bearing assembly of the static pressure spindle unit is improved, and finally the assembly accuracy of the entire static pressure spindle unit is improved to improve the working accuracy of the static pressure spindle unit.
[0063] Figure 1In the figure, the hydrostatic front bearing 102 and the hydrostatic rear bearing 103 are named according to the position of the tool installed on the hydrostatic spindle unit 1. The tool is installed at the front end, and the end bearing is also set at the front end. It is necessary to measure the runout error of the end bearing hydrostatic action surface 109 of the hydrostatic front bearing 102 with the first pressure annular hydrostatic oil chamber 111. If the tool is installed at the front end and the end bearing is set at the rear end, the first pressure annular hydrostatic oil chamber 111 is set on the hydrostatic rear bearing 103, and its end bearing hydrostatic action surface 109 is also on the hydrostatic rear bearing 103. When the end face runout measurement equipment of the present invention is used to measure the runout error, it is necessary to turn the hydrostatic rear bearing 103 upward relative to the hydrostatic front bearing 102. The other structural descriptions and measurement methods are the same as above. Other applicable occasions will not be repeated.
[0064] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.
Claims
1. A hydrostatic spindle unit end face runout measurement device, characterized in that: The invention comprises a centering device (2), a measuring device (3) and a supporting device (4), wherein the supporting device (4) is arranged at the lower part of the hydrostatic spindle unit (1), the centering device (2) is installed at the top end of the supporting device (4), and is movably connected to the inner hole of the bearing assembly arranged on the inner side of the hydrostatic spindle unit (1), and is used to form a circumferential positioning for the bearing assembly of the hydrostatic spindle unit (1) in the radial direction; the measuring device (3) is rotatably connected to the top end of the centering device (2), and is used to realize the measurement of the runout error of the hydrostatic action surface (109) of the end face bearing of the bearing assembly of the hydrostatic spindle unit (1).
2. The hydrostatic spindle unit end face runout measuring device according to claim 1, characterized in that: The centering device (2) comprises: a centering shaft (201), a first thin-walled sleeve (205) and a second thin-walled sleeve (210), wherein the first thin-walled sleeve (205) and the second thin-walled sleeve (210) are respectively sleeved on the lower end and the upper end of the centering shaft (201); a first liquid plastic channel (206) is provided between the centering shaft (201) and the first thin-walled sleeve (205), and a second liquid plastic channel (211) is provided between the centering shaft (201) and the second thin-walled sleeve (210); a first liquid plastic input channel and a first liquid plastic output channel leading to the first liquid plastic channel (206) are provided on the lower end surface of the centering shaft (201), and a first pressure screw (211) is placed in the first liquid plastic input channel from the outside to the inside. 02) and a first slide column (204), a first screw plug (203) is provided on the opening of the first liquid plastic output channel; a second liquid plastic input channel and a second liquid plastic output channel leading to a second liquid plastic channel (211) are provided on the upper end surface of the centering shaft (201), a second pressure screw (214) and a second slide column (215) are placed in the second liquid plastic input channel from the outside to the inside, and a second screw plug (213) is provided on the opening of the second liquid plastic output channel; the first liquid plastic channel (206) between the first thin-walled sleeve (205) and the centering shaft (201) is filled with liquid plastic; the second liquid plastic channel (211) between the second thin-walled sleeve (210) and the centering shaft (201) is filled with liquid plastic.
3. The hydrostatic spindle unit end face runout measuring device according to claim 2, characterized in that: A handle is provided below the first pressurizing screw (202) and above the second pressurizing screw (214).
4. A hydrostatic spindle unit end face runout measuring device as claimed in claim 2 or 3, characterized in that: The measuring device (3) comprises: a composite bearing (303), a first spacer (301), a slewing support (302), a second spacer (307), a locking nut (308), a bearing sleeve (304), a pressure cover (306) and a displacement sensor measuring mechanism. A shaft shoulder is arranged at the upper end of the centering shaft (201). The first spacer (301), the inner ring of the composite bearing (303) and the second spacer (307) are sequentially arranged on the centering shaft (201) from bottom to top. The upper end is locked downward by the locking nut (308) to achieve the first displacement sensor measuring mechanism. The lower end face of a spacer sleeve (301) abuts against the shoulder end face of the centering shaft (201); a rotating bracket (302) is arranged outside the outer ring of the composite bearing (303); a bearing sleeve (304) and a pressure cover (306) are sequentially installed above the rotating bracket (302); the pressure cover (306) and the rotating bracket (302) are connected by screws to achieve axial positioning of the composite bearing (303); a displacement sensor measuring mechanism is installed on the outer wall of the rotating bracket (302), and a displacement sensor (326) is arranged inside the displacement sensor measuring mechanism.
5. The hydrostatic spindle unit end face runout measuring device according to claim 4, characterized in that: The displacement sensor measuring mechanism comprises a guide rail beam (311), an upper plate (314), a lower plate (318), a first upper bearing support assembly (315), a second upper bearing support assembly (319), a first vertical bearing support assembly (313), a second vertical bearing support assembly (316), a third vertical bearing support assembly (321), a fourth vertical bearing support assembly (322), a first lower bearing support assembly (324) and a second lower bearing support assembly (325); the guide rail beam (311) is arranged on the outer side of the slewing bracket (302), and the guide rail direction thereof is perpendicular to the slewing center line OO of the composite bearing (303); the first upper bearing support assembly (315) and the second upper bearing support assembly (319) are installed one inside and one outside the upper plate (314) ; The first lower bearing support assembly (324) and the second lower bearing support assembly (325) are installed inside and outside the lower plate (318); a sensor bracket (317) is provided on one side of the lower plate (318); the second vertical bearing support assembly (316), the third vertical bearing support assembly (321) and the first vertical bearing support assembly (313), and the fourth vertical bearing support assembly (322) are respectively provided inside and outside the two sides of the guide rail crossbeam (311); the first vertical bearing support assembly (313), the second vertical bearing support assembly (316), the third vertical bearing support assembly (321) and the fourth vertical bearing support assembly (322) are respectively connected to the upper plate (314) and the lower plate (318) at both ends, and springs are provided inside.
6. A hydrostatic spindle unit end face runout measuring device as claimed in claim 5, characterized in that: The measuring device (3) further comprises a worm wheel (305), a worm (309), a box seat (310) and a motor (312); the worm wheel (305) is arranged between a bearing sleeve (304) and a pressure cover (306) above a slewing support (302); the box seat (310) is mounted on the upper end surface of a body shell (101) of a hydrostatic spindle unit (1); the worm (309) is supported in a side wall hole of the box seat (310) by a rolling bearing; one end of the worm (309) is externally provided with a motor (312) and is fixedly connected to an output shaft of the motor (312); and the worm (309) is meshed with the worm wheel (305).
7. A hydrostatic spindle unit end face runout measuring device as claimed in claim 6, characterized in that: The displacement sensor measuring mechanism also includes a clamping mechanism (320) and a positioning device (323); two positioning devices (323) are provided on one side of the upper plate (314), and a clamping mechanism (320) is provided on the other side of the upper plate (314).
8. The hydrostatic spindle unit end face runout measuring device according to claim 7, characterized in that: The support device comprises a shaft support seat (401) and a body shell support seat (402), wherein the shaft support seat (401) is mounted on the body shell support seat (402); the shaft support seat (401) is arranged below the centering shaft (201), and the body shell support seat (402) is arranged below the body shell (101) of the static pressure spindle unit (1).
9. A method for measuring the end face runout of a static pressure spindle unit, characterized in that: The steps include: S1: The hydrostatic front bearing (102), the hydrostatic rear bearing (103) and the body shell (101) of the hydrostatic spindle unit (1) are assembled into an assembly; S2: grinding the front bearing static pressure action cylinder (107) of the static pressure front bearing (102) and the rear bearing static pressure action cylinder (108) of the static pressure rear bearing (103) in step S1 by a grinding rod, thereby improving the coaxiality of the two holes of the front bearing static pressure action cylinder (107) and the rear bearing static pressure action cylinder (108); S3: placing the assembly completed in step S2 in the vertical direction so that the end bearing static pressure action surface (109) of the static pressure front bearing (102) faces upward, placing a support device (4) below the body shell (101), and adjusting the support device (4) so that the assembly is placed stably; S4: placing the centering device (2) of the end face runout measurement equipment from top to bottom into the hydrostatic front bearing (102) and the hydrostatic rear bearing (103) of the hydrostatic spindle unit (1), and adjusting the shaft support seat (401) of the support device (4) at the lower end of the centering device (2) to form a stable support for the centering device (2); S5: Rotate the first pressure screw (202) and the second pressure screw (214) of the centering device (2) respectively, so that the liquid plastic in the first liquid plastic channel (206) and the second liquid plastic channel (211) forces the first thin-walled sleeve (205) and the second thin-walled sleeve (210) to expand radially and respectively abut against the static pressure action cylinder (108) of the rear bearing and the static pressure action cylinder (107) of the front bearing, so that the centering device (2) forms a fixed connection with the static pressure front bearing (102) and the static pressure rear bearing (103), thereby achieving radial circumferential positioning of the static pressure front bearing (102) and the static pressure rear bearing (103); S6: installing the measuring device (3) and adjusting the distance between the displacement sensor (326) and the static pressure action surface (109) of the end bearing, so that the displacement sensor (326) can sense a distance signal between the displacement sensor (326) and the static pressure action surface (109) of the end bearing; S7: Manually rotate the swivel bracket (302) of the measuring device (3) to make the guide rail crossbeam (311) rotate around the swivel center line OO of the composite bearing (303), and record the displacement signal measured by the displacement sensor (326) at each rotation of the swivel bracket (302); S8: changing the radial position of the guide rail motion mechanism where the upper plate (314) of the displacement sensor measuring mechanism of the measuring device (3) is located on the guide rail crossbeam (311) relative to the composite bearing (303), and recording the displacement signal of the displacement sensor (326) according to step S7; after multiple cycles, the measurement is completed, and the end face runout measurement equipment is taken out from the hydrostatic spindle unit (1); S9: using a data analysis system to process the displacement signals measured in steps S7 and S8 to obtain the end face total runout error of the static pressure action surface (109) of the end face bearing; S10: according to the total runout error of the end surface of the end bearing static pressure action surface (109) in step S9, reducing the total runout error by scraping or grinding; S11: Measure the end face total runout error of the end face bearing static pressure action surface (109) again according to steps S7 to S9. If the end face total runout error does not meet the assembly accuracy requirement, implement step S10 until the accuracy requirement is met.
10. A method for measuring end face runout of a hydrostatic spindle unit according to claim 9, characterized in that: Step S7 is replaced by: S7': driven by the motor (312), under the transmission action of the worm wheel (305) and the worm (309), the slewing bracket (302) rotates, so that the guide rail crossbeam (311) rotates around the rotation center line OO of the composite bearing (303), and the displacement signal measured by the displacement sensor (326) at each rotation of the slewing bracket (302) is recorded.