High-precision direct-drive static pressure supporting structure of numerical control rotary table

Abstract

The invention discloses a numerical control rotary table high-precision direct-drive static pressure supporting structure which comprises a base, a band-type brake mechanism, a torque motor, a motor connecting piece, a workbench, a bearing fixing piece and a static pressure bearing. The band-type brake mechanism is vertically mounted in the middle of the mounting cavity; a stator of the torque motor is fixedly connected with the base; the motor connecting pieces are located in the mounting cavity and distributed on the periphery of the band-type brake mechanism at intervals. The motor connecting pieces are fixedly connected with a rotor of the torque motor. The workbench is fixedly connected with the motor connecting piece and extends out of the mounting cavity; the bearing fixing pieces are located in the mounting cavity and distributed on the periphery of the motor connecting piece at intervals, and the bearing fixing pieces are fixedly connected with the base; the hydrostatic bearing is installed on the bearing fixing piece and located between the working table and the motor connecting piece, so that working oil films are formed in the gap between the hydrostatic bearing and the working table and the gap between the hydrostatic bearing and the motor connecting piece after oil is fed, and the rotation precision is improved.

Description

Technical Field

[0001] The invention relates to the technical field of machine tool functional components, and more specifically to a high-precision direct-drive static pressure support structure for a numerically controlled turntable. Background Art

[0002] The CNC rotary table is one of the key functional components of the machining center machine tool. It provides the rotary axis for the machine tool and bears the weight of the workpiece. The positioning accuracy and rotation dynamic accuracy of the rotary table directly affect the machining accuracy of the workpiece, especially for high-precision machine tools. However, the accuracy of the existing rotary table needs to be improved and cannot meet the needs of high-end machine tools.

[0003] Therefore, providing a high-precision direct-drive hydrostatic support structure for a CNC turntable is an issue that needs to be urgently addressed by those skilled in the art. Summary of the invention

[0004] In view of this, the present invention provides a high-precision direct-drive hydrostatic support structure for a CNC turntable to improve the rotation accuracy.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A high-precision direct-drive hydrostatic support structure for a numerically controlled turntable, comprising a base, a brake mechanism, a torque motor, a motor connector, a workbench, a bearing fixing member and a hydrostatic bearing, wherein the base has a vertically through-going mounting cavity; the brake mechanism is vertically installed in the middle of the mounting cavity; the torque motor is located in the mounting cavity and its stator is fixedly connected to the base; the motor connector is located in the mounting cavity and is spaced apart at the periphery of the brake mechanism, and the motor connector is fixedly connected to the rotor of the torque motor; the workbench is fixedly connected to the motor connector and extends out of the mounting cavity; the bearing fixing member is located in the mounting cavity and is spaced apart at the periphery of the motor connector, and the bearing fixing member is fixedly connected to the base; the hydrostatic bearing is installed on the bearing fixing member and is located between the workbench and the motor connector, so that a working oil film is formed in the gap between the hydrostatic bearing and the workbench and in the gap between the hydrostatic bearing and the motor connector after oil is filled.

[0007] By adopting the above technical solution, the beneficial effects of the present invention are:

[0008] The working oil film bears the working load to form a stable static pressure oil film support, thus ensuring the high rigidity and high rotation accuracy of the turntable.

[0009] Furthermore, it also includes an oil pan, which is located in the installation cavity and is spaced apart around the motor connector, and is located below the bearing fixing member. The oil pan is fixedly connected to the base, thereby forming a first oil pool between the oil pan and the bearing fixing member; the base has a second oil pool leading to the outside; the gap between the hydrostatic bearing and the motor connector forms a first oil return channel, the gap between the hydrostatic bearing and the workbench forms a second oil return channel, and the first oil return channel is connected to the second oil return channel; the first oil return channel is connected to the first oil pool, the second oil return channel is connected to the second oil pool, and the first oil pool is connected to the second oil pool through the oil hole opened on the base, thereby forming an oil unloading circuit.

[0010] The beneficial effect of adopting the above further technical solution is to realize a zero-pressure hydraulic oil drain circuit and ensure smooth reflux of the hydraulic oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0012] Figure 1 The accompanying drawing is a schematic diagram of the overall structure of a high-precision direct-drive static pressure support structure for a CNC turntable provided by the present invention;

[0013] Figure 2 The accompanying drawing is a front view of a high-precision direct-drive static pressure support structure for a CNC turntable provided by the present invention;

[0014] Figure 3 The attached picture is Figure 2 Middle AA section view;

[0015] Figure 4 The attached picture is Figure 3 Schematic diagram of the enlarged structure of part A. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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.

[0017] like Figure 1-4As shown, an embodiment of the present invention discloses a high-precision direct-drive hydrostatic support structure for a numerically controlled turntable, comprising a base 1, a brake mechanism 2, a torque motor 3, a motor connector 4, a workbench 5, a bearing fixing member 6 and a hydrostatic bearing 7, wherein the base 1 has a vertically through-going mounting cavity; the brake mechanism 2 is vertically mounted in the middle of the mounting cavity; the torque motor 3 is located in the mounting cavity and its stator is fixedly connected to the base 1; the motor connector 4 is located in the mounting cavity and is spaced apart from the periphery of the brake mechanism 2, and the motor connector 4 is fixedly connected to the rotor of the torque motor 3; the workbench 5 is fixedly connected to the motor connector 4 and extends out of the mounting cavity; the bearing fixing member 6 is located in the mounting cavity and is spaced apart from the periphery of the motor connector 4, and the bearing fixing member 6 is fixedly connected to the base 1; the hydrostatic bearing 7 is mounted on the bearing fixing member 6 and is located between the workbench 5 and the motor connector 4, so that a working oil film is formed in the gap between the hydrostatic bearing 7 and the workbench 5 and in the gap between the hydrostatic bearing 7 and the motor connector 4 after oil is supplied, so as to bear the working load. The present invention adopts closed adaptive internal feedback throttling control liquid hydrostatic bearing technology to realize automatic adjustment of hydraulic oil film gap and automatic feedback of oil film pressure (the gap between the top end of the hydrostatic bearing 7 and the bottom end of the worktable 5, and the gap between the bottom end of the hydrostatic bearing 7 and the top end of the motor connector 4 form an axial oil film, the gap between the side wall of the hydrostatic bearing 7 and the side wall of the worktable 5 forms a radial oil film, and there are several groups of oil chambers in the circumferential direction of the hydrostatic bearing 7, and a throttling device is provided between each group of corresponding oil chambers. Under the action of the throttling device, the radial oil film pressure is automatically adjusted with the change of external load. Similarly, the axial oil film pressure is automatically adjusted with the change of external load), forming a stable hydrostatic oil film support, thereby ensuring the high rigidity and high rotation accuracy of the turntable.

[0018] Specifically, it also includes an oil pan 8, which is located in the installation cavity and is spaced apart around the motor connector 4, and is located below the bearing fixing member 6. The oil pan 8 is fixedly connected to the base 1, thereby forming a first oil pool 9 between the oil pan 8 and the bearing fixing member 6; the base 1 has a second oil pool leading to the outside; the gap between the hydrostatic bearing 7 and the motor connector 4 forms a first oil return channel, and the gap between the hydrostatic bearing 7 and the workbench 5 forms a second oil return channel, and the first oil return channel is connected to the second oil return channel; the first oil return channel is connected to the first oil pool 9, and the second oil return channel is connected to the second oil pool, and the first oil pool 9 is connected to the second oil pool through the oil hole opened on the base 1, thereby forming an oil unloading circuit, thereby realizing an oil leakage circuit of zero-pressure hydraulic oil, and ensuring smooth reflux of hydraulic oil.

[0019] Specifically, the brake mechanism 2 expands its elastic sleeve to lock the motor connector 4 (the brake mechanism 2 is composed of an elastic sleeve and a fixing part. After the pressure oil is passed through, the elastic sleeve expands and contacts the motor connector 4, and the motor connector 4 is locked by friction force), thereby ensuring the stability and reliability of the turntable positioning processing.

[0020] Specifically, the fixed connection method in this embodiment is bolt connection.

[0021] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0022] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high-precision direct-drive static pressure support structure for a CNC turntable, characterized in that: It includes a base, a brake mechanism, a torque motor, a motor connecting part, a workbench, a bearing fixing part and a hydrostatic bearing, wherein the base has a vertically through-mounting cavity; the brake mechanism is vertically installed in the middle of the mounting cavity; the torque motor is located in the mounting cavity and its stator is fixedly connected to the base; the motor connecting part is located in the mounting cavity and is spaced apart from the periphery of the brake mechanism, and the motor connecting part is fixedly connected to the rotor of the torque motor; the workbench is fixedly connected to the motor connecting part and extends out of the mounting cavity; the bearing fixing part is located in the mounting cavity and is spaced apart from the periphery of the motor connecting part, and the bearing fixing part is fixedly connected to the base; the hydrostatic bearing is installed on the bearing fixing part and is located between the workbench and the motor connecting part, so that a working oil film is formed in the gap between the hydrostatic bearing and the workbench and in the gap between the hydrostatic bearing and the motor connecting part after oil is filled.

2. The high-precision direct-drive static pressure support structure for a CNC turntable according to claim 1, characterized in that: It also includes an oil pan, which is located in the installation cavity and is spaced apart around the motor connector, and is located below the bearing fixing member. The oil pan is fixedly connected to the base, thereby forming a first oil pool between the oil pan and the bearing fixing member; the base has a second oil pool leading to the outside; the gap between the hydrostatic bearing and the motor connector forms a first oil return channel, the gap between the hydrostatic bearing and the workbench forms a second oil return channel, and the first oil return channel is connected to the second oil return channel; the first oil return channel is connected to the first oil pool, the second oil return channel is connected to the second oil pool, and the first oil pool is connected to the second oil pool through the oil hole opened on the base, thereby forming an oil unloading circuit.

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