A high-precision horizontal rotary table

Abstract

This utility model discloses a high-precision horizontal rotary table, relating to the field of precision machining equipment technology, comprising: a housing, a spindle core, a front bearing assembly, a rear bearing assembly, a sleeve, a worktable, a brake, a motor rotor-stator assembly, and an angle encoder; the spindle core is fixed to the housing via the front and rear bearing assemblies, the front bearing assembly having a transition fit with the spindle core and being fixed by end face screws, the outer ring of the front bearing assembly having a transition fit with the housing and being fixed by end face screws; the rear bearing assembly having a transition fit with the spindle core, and the bearing sleeve having a clearance fit with the housing; the worktable is fixed to the front end face of the spindle core, the brake is fixedly mounted on the housing, the output end of the motor rotor-stator assembly is connected to the spindle core, and the angle encoder is mounted on the sleeve; in the technical solution provided by this utility model, by using cylindrical roller rotary table bearings or thrust angular contact ball rotary table bearings in the front bearing assembly and having a transition fit with the spindle core and housing, the axial load-bearing capacity is significantly improved.

Description

Technical Field

[0001] This utility model relates to the field of precision machining equipment technology, and in particular to a high-precision horizontal rotary table. Background Technology

[0002] High-precision horizontal rotary tables are key equipment in the fields of precision machining and measurement. Their core function is to achieve high-precision angular positioning and stable torque output around a rotation axis. In existing technologies, rotary tables mostly employ a belt-driven transmission structure, using a belt to rotate the spindle. While this structure has advantages such as simplicity and low cost, it suffers from the following significant drawbacks:

[0003] Belt drives are prone to transmission errors due to elastic deformation or slippage, making it difficult to meet the micron-level angular positioning requirements; belts are prone to vibration during high-speed rotation, requiring the sacrifice of speed to maintain rigidity, resulting in a decline in the overall performance of the turntable; traditional mechanical brakes rely on friction plates for clamping, which has problems such as braking lag, heat generation and deformation, and cannot achieve rapid locking; in addition, the bearing assembly undergoes thermal expansion due to temperature rise, causing axial movement of the main shaft, affecting long-term operating accuracy. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a high-precision horizontal rotary table to solve the problems in the background art.

[0005] In view of this, the present invention provides a high-precision horizontal rotary table, comprising:

[0006] Housing, spindle core, front bearing assembly, rear bearing assembly, sleeve, worktable, holding brake, motor rotor-stator assembly and angle encoder;

[0007] The main spindle core is fixed to the housing via a front bearing assembly and a rear bearing assembly. The front bearing assembly is transitionally fitted to the main spindle core and fixed by end face screws. The outer ring of the front bearing assembly is transitionally fitted to the housing and fixed by end face screws. The rear bearing assembly is transitionally fitted to the main spindle core, and the bearing sleeve is clearance fitted to the housing.

[0008] The worktable is fixed to the front end face of the spindle core, the brake is fixedly installed on the housing, the output end of the motor rotor-stator assembly is connected to the spindle core, and the angle encoder is installed on the sleeve.

[0009] Optionally, the brake includes a thin spring plate, a brake base, and an oil chamber. The thin spring plate is installed between the brake base and the end face of the housing, and the oil chamber is located between the thin spring plate and the brake base and has sealing rings at both ends.

[0010] The oil chamber has a ring-shaped structure and is coaxially arranged with the main shaft core. The oil chamber is connected to an external pressure oil source through a hydraulic pipeline.

[0011] Optionally, the motor rotor-stator assembly includes a rotor that is interference-fitted with the main shaft core and a stator installed in the inner bore of the sleeve.

[0012] Optionally, the angle encoder includes a circular grating disk and a reading head;

[0013] The circular grating disk is fixed to the rear end of the main spindle core and rotates with the main spindle core to achieve angle measurement;

[0014] The reading head is mounted on a sleeve, which is fixed to the housing by threads or screws.

[0015] The reading head is indirectly connected to the housing via a sleeve to form a fixed measurement reference.

[0016] Optionally, the angle encoder may be a circular grating encoder or a magnetic grating encoder.

[0017] Optionally, the sleeve and the housing are fixed by a threaded connection or by locking screws.

[0018] Optionally, the motor rotor-stator assembly adopts a permanent magnet synchronous motor structure.

[0019] As can be seen from the above technical solutions, the embodiments of this utility model have the following advantages:

[0020] 1. This utility model discloses a high-precision horizontal rotary table. By adopting cylindrical roller rotary table bearings or thrust angular contact ball rotary table bearings in the front bearing assembly and transition fit with the main spindle core and housing, the axial load-bearing capacity is significantly improved. The rear bearing assembly is clearance fit with the main spindle core. With the thread adjustment function of the sleeve, the axial deformation caused by thermal expansion can be dynamically compensated to ensure the coaxiality of the main spindle core under high temperature conditions.

[0021] 2. This utility model adopts a permanent magnet synchronous motor direct drive structure for the motor rotor-stator assembly, with the rotor directly interference-fitted to the main shaft core, eliminating transmission chain errors and ensuring accuracy at high speeds.

[0022] 3. In this utility model, the brake base does not move, and the oil pressure causes the spring brake plate to deform and grip the main shaft.

[0023] These features and advantages of the present invention will be disclosed in detail in the following specific embodiments and accompanying drawings. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings:

[0025] Figure 1 This is a schematic cross-sectional view of the present invention.

[0026] Figure 2 This is a schematic diagram of the structure of this utility model;

[0027] Figure 3 This is a schematic diagram of the structure of the holding brake of this utility model.

[0028] Explanation of reference numerals in the attached drawings: 1. Housing; 2. Main spindle core; 3. Front bearing assembly; 4. Rear bearing assembly; 5. Sleeve; 6. Worktable; 7. Brake; 71. Thin spring sheet; 72. Brake base; 8. Motor rotor-stator assembly; 9. Angle encoder. Detailed Implementation

[0029] The technical solutions of the present utility model will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of the present utility model and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present utility model.

[0030] A high-precision horizontal rotary table according to an embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0031] Example

[0032] For easier understanding, please refer to Figures 1 to 3 An embodiment of a high-precision horizontal rotary table provided by this utility model includes:

[0033] 1. Housing; 2. Main spindle core; 3. Front bearing assembly; 4. Rear bearing assembly; 5. Sleeve; 6. Worktable; 7. Brake; 8. Motor rotor-stator assembly; and 9. Angle encoder.

[0034] The main spindle core 2 is fixed to the housing 1 by the front bearing assembly 3 and the rear bearing assembly 4. The front bearing assembly 3 is transitionally fitted with the main spindle core 2 and fixed by end face screws. The outer ring of the front bearing assembly 3 is transitionally fitted with the housing 1 and fixed by end face screws. The rear bearing assembly 4 is transitionally fitted with the main spindle core 2, and the bearing sleeve 5 is clearance fitted with the housing 1.

[0035] The worktable 6 is fixed to the front end face of the spindle core 2, the brake 7 is fixedly installed on the housing 1, the output end of the motor rotor-stator assembly 8 is connected to the spindle core 2, and the angle encoder 9 is installed on the sleeve 5.

[0036] It should be noted that the spindle core 2 is coaxially mounted within the housing 1 via the front bearing assembly 3 and the rear bearing assembly 4. The front bearing assembly 3 uses a cylindrical roller rotary table bearing or a thrust angular contact ball rotary table bearing, with its inner ring transition-fitted to the spindle core 2 and its outer ring transition-fitted to the bearing bore of the housing 1. The rear bearing assembly 4 uses a single-row cylindrical roller bearing, with its inner ring clearance-fitted to the spindle core 2 and its outer ring press-fitted into the rear end bore of the housing 1 via a sleeve 5. The worktable 6 is bolted to the front flange of the spindle core 2.

[0037] The holding brake 7 is fixed to the front end of the housing 1 by bolts, and its annular oil chamber is connected to an external pressure oil source through a hydraulic pipeline.

[0038] The angle encoder 9 adopts a circular grating encoder. The circular grating disk is fixed to the main shaft core 2 by screws, and the sleeve 5 is fixed to the housing 1 by screws to ensure that the reading head and the housing 1 form a fixed measurement reference.

[0039] In some embodiments, the brake 7 includes a thin spring plate 71, a brake base 72 and an oil chamber. The thin spring plate 71 is installed between the brake base 72 and the end face of the housing 1. The oil chamber is disposed between the thin spring plate 71 and the brake base 72 and is provided with sealing rings at both ends.

[0040] The oil chamber has a ring structure and is coaxially arranged with the main spindle core 2. The oil chamber is connected to an external pressure oil source through a hydraulic pipeline.

[0041] It should be noted that the holding brake 7 further includes:

[0042] The thin spring sheet 71 is made of spring steel with a thickness of 0.8mm and is fixed between the brake base 72 and the end face of the housing 1 by screws.

[0043] The annular oil chamber is formed by a thin spring plate 71 and a brake base 72, and has two fluororubber sealing rings embedded inside. The oil chamber is connected to an external hydraulic station through radial oil holes.

[0044] In some embodiments, the motor rotor-stator assembly 8 includes a rotor that is interference-fitted with the main shaft core 2 and a stator installed in the inner hole of the sleeve 5.

[0045] It should be noted that the motor rotor-stator assembly 8 adopts a permanent magnet synchronous motor structure: the rotor is directly fitted into the middle of the main shaft core 2 through an interference fit, and the stator is installed in the inner hole of the sleeve 5 through an transition fit. The gap between the stator and rotor is controlled at 0.2-0.5mm.

[0046] In some embodiments, the angle encoder 9 includes a circular grating disk and a reading head;

[0047] The circular grating disk is fixed to the rear end of the main spindle core 2 and rotates with the main spindle core 2 to achieve angle measurement;

[0048] The reading head is mounted on the sleeve 5, and the sleeve 5 is fixed to the housing 1 by threads or screws;

[0049] The reading head is indirectly connected to the housing 1 via the sleeve 5 to form a fixed measurement reference.

[0050] It should be noted that the angle encoder 9 is a circular grating encoder or a magnetic grating encoder with a grating pitch of 30 micrometers and a reading head resolution of 26 bits. During installation, the gap between the reading head and the grating disk is finely adjusted using the adjusting screw on the side of the sleeve 5, and the measurement reference is calibrated using a laser interferometer.

[0051] In some embodiments, the sleeve 5 is connected to the housing 1 by a threaded connection or a locking screw. The outer wall of the sleeve 5 is threaded and connected to the inner hole of the housing 1 by a threaded connection. The axial position is fixed by a locking nut to achieve the preload adjustment of the rear bearing assembly 4.

[0052] Working principle: The front bearing assembly 3 is heated to 120℃ and then pressed onto the front end of the spindle core 2. After cooling, a transition fit is formed. The sleeve 5 is screwed into the threaded hole at the rear end of the housing 1. The radial runout of the rear bearing assembly 4 is adjusted using a dial indicator and then locked. After the worktable 6 is installed, the end face runout is detected using the three-point support method. If the runout exceeds the tolerance, the flange surface of the spindle core 2 is ground to correct it.

[0053] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A high precision horizontal rotary table, characterized by: include: Housing (1), spindle core (2), front bearing assembly (3), rear bearing assembly (4), sleeve (5), worktable (6), brake (7), motor rotor-stator assembly (8), and angle encoder (9); The main spindle core (2) is fixed to the housing (1) by the front bearing assembly (3) and the rear bearing assembly (4). The front bearing assembly (3) is transitionally fitted with the main spindle core (2) and fixed by end face screws. The outer ring of the front bearing assembly (3) is transitionally fitted with the housing (1) and fixed by end face screws. The rear bearing assembly (4) is transitionally fitted with the main spindle core (2), and the bearing sleeve (5) is clearance fitted with the housing (1). The worktable (6) is fixed to the front end face of the spindle core (2), the brake (7) is fixedly installed on the housing (1), the output end of the motor rotor-stator assembly (8) is connected to the spindle core (2), and the angle encoder (9) is installed on the sleeve (5).

2. A high precision horizontal rotary table according to claim 1, characterized in that: The brake (7) includes a thin spring plate (71), a brake base (72) and an oil chamber. The thin spring plate (71) is installed between the brake base (72) and the end face of the housing (1). The oil chamber is located between the thin spring plate (71) and the brake base (72) and has sealing rings at both ends. The oil chamber has a ring structure and is coaxially arranged with the main shaft core (2). The oil chamber is connected to an external pressure oil source through a hydraulic pipeline.

3. A high precision horizontal rotary table according to claim 1, characterized in that: The motor rotor-stator assembly (8) includes a rotor that is interference-fitted with the main shaft core (2) and a stator installed in the inner hole of the sleeve (5).

4. A high-precision horizontal rotary table according to claim 1, characterized in that: The angle encoder (9) includes a circular grating disk and a reading head; The circular grating disk is fixed to the rear end of the main spindle (2) and rotates with the main spindle (2) to achieve angle measurement; The reading head is mounted on the sleeve (5), and the sleeve (5) is fixed to the housing (1) by threads or screws; The reading head is indirectly connected to the housing (1) through the sleeve (5) to form a fixed measurement reference.

5. A high-precision horizontal rotary table according to claim 1, characterized in that: The angle encoder (9) is a circular grating encoder or a magnetic grating encoder.

6. A high-precision horizontal rotary table according to claim 1, characterized in that: The sleeve (5) and the housing (1) are connected by threads or fixed with locking screws.

7. A high-precision horizontal rotary table according to claim 1, characterized in that: The motor rotor-stator assembly (8) adopts a permanent magnet synchronous motor structure.

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