Ultra-precision hydrostatic bearing turntable

Abstract

The present application relates to a kind of rotary table structures for machine tool processing.The purpose is to provide a kind of ultra-precision hydrostatic bearing rotary table with high rotation accuracy, high stiffness, simple structure, smooth operation, large applicable speed range.The ultra-precision hydrostatic bearing rotary table of the present application includes rotary table base body, the inner circle of rotary table base body is equipped with copper bushing, the upper and lower surfaces of rotary table base body are each equipped with one copper ring, copper bushing and copper ring are fixedly connected with rotary table base body, copper bushing and copper ring constitute copper bushing assembly, the inside of base body is provided with shaft core, shaft core is fixedly connected with end cover, the adjacent surface of shaft core and copper bushing, end cover and copper ring is all gap fit, and ultra-precision water is filled between copper bushing assembly and shaft core and end cover.

Description

Technical Field

[0001] This invention relates to the field of machine tool technology, and in particular to an ultra-precision hydrostatic bearing rotary table. Background Technology

[0002] In applications such as scientific research and precision measurement in high-end manufacturing, high-precision rotary tables are frequently used. Through rotation and in conjunction with appropriate machining equipment, they enable the control of workpiece machining. Bearing rotary tables, in particular, can achieve circumferential feed motion in machining, indexing and changing the workpiece's surface. Used in conjunction with automatic tool changers, they allow multiple processes to be completed on several sides of a workpiece in a single setup, significantly improving work efficiency. They are an indispensable basic functional component of many precision CNC machine tools.

[0003] Bearing rotary tables are widely used in precision and ultra-precision CNC machine tools, such as lathes, grinding machines, four-axis machine tools, and five-axis machine tools with rotary axes. The precision of the bearing rotary table determines the accuracy level of the machine tool. For precision and ultra-precision CNC machine tools with rotary axes, the bearing rotary table is required to have high rotational accuracy, high rigidity, large load-bearing capacity, smooth operation, a wide applicable speed range, and long service life. The bearing rotary table is an important component of ultra-precision machining technology and can improve the overall accuracy of precision and ultra-precision CNC machine tools.

[0004] Existing bearing turntables generally use rolling bearings for support, which limits their rotational accuracy. During operation, friction between the rolling elements and the bearing raceways easily generates vibration and causes wear, leading to a decrease in accuracy after a period of use. While existing hydrostatic turntables offer higher rotational accuracy, their structural components are complex to manufacture, making it difficult to guarantee component precision. Most of these turntables lack braking devices, and after indexing, stable positioning accuracy cannot be guaranteed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an ultra-precision hydrostatic bearing turntable with high rotational accuracy, high rigidity, stable operation and a wide applicable speed range.

[0006] This invention relates to an ultra-precision hydrostatic bearing turntable, comprising a turntable base, a copper sleeve installed on the inner circle of the turntable base, and a copper ring installed on each of the upper and lower surfaces of the turntable base. The copper sleeve and the copper ring are fixedly connected to the turntable base, forming a copper sleeve assembly. A shaft core is provided inside the base, and the shaft core is fixedly connected to an end cover. The surfaces adjacent to the shaft core and the copper sleeve, and the end cover and the copper ring, are all clearance fits. Ultra-precision water is filled between the copper sleeve assembly, the shaft core, and the end cover.

[0007] The present invention relates to an ultra-precision hydrostatic bearing turntable, wherein a copper sleeve assembly consisting of two copper rings and a copper sleeve forms a C-shaped structure with an outward opening around the inner edge of the turntable base.

[0008] The present invention relates to an ultra-precision hydrostatic bearing turntable, wherein the upper and lower sides of the shaft core are respectively fixedly connected to an end cap to form an I-shaped structure.

[0009] The present invention relates to an ultra-precision hydrostatic bearing turntable, wherein a water inlet pipe connector is provided on one side of the turntable base, the water inlet pipe connector is connected to a water inlet channel opened inside the turntable base, and the other end of the water inlet channel is connected to the gap between the shaft core and the copper sleeve, and between the end cover and the copper ring.

[0010] The present invention relates to an ultra-precision hydrostatic bearing turntable, wherein a return water pipe joint is provided on one side of the turntable base, the return water pipe joint is connected to a return water channel opened inside the turntable base, and the other end of the return water channel is connected to the gap between the shaft core and the copper sleeve, and between the end cover and the copper ring.

[0011] The present invention relates to an ultra-precision hydrostatic bearing turntable, wherein an air inlet pipe connector is provided on one side of the turntable base, the air inlet pipe connector is connected to an air inlet channel opened inside the turntable base, and the other end of the air inlet channel is connected between the end cover and the copper ring.

[0012] The present invention relates to an ultra-precision hydrostatic bearing turntable, wherein a sealing ring is provided between the copper ring and the lower end cover.

[0013] The difference between the ultra-precision hydrostatic bearing turntable of the present invention and the prior art is that the ultra-precision hydrostatic bearing turntable of the present invention has copper rings and copper sleeves installed on the turntable. The compressed water that has been precisely filtered is throttled through them, thereby supporting the rotation of the main shaft component.

[0014] The ultra-precision hydrostatic bearing turntable of this invention adopts a hydraulic bearing support structure. The turntable shaft core assembly and the copper sleeve assembly cooperate with each other. The shaft core is wrapped inside the copper sleeve to ensure high precision of the turntable surface rotation, as well as high load-bearing capacity and stable operation.

[0015] The ultra-precision hydrostatic bearing turntable of this invention adopts a pneumatic seal, which uses compressed air to seal the gap between the end cover and the copper ring, and embeds a sealing ring in the lower end cover to make it difficult for the hydraulic medium to flow out, thus ensuring the seal of the turntable.

[0016] The ultra-precision hydrostatic bearing turntable of the present invention will be further described below with reference to the accompanying drawings. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the ultra-precision hydrostatic bearing turntable of the present invention;

[0018] Figure 2 This is a top view of the ultra-precision hydrostatic bearing turntable of the present invention;

[0019] Figure 3 This is a schematic diagram of the water inlet structure of the ultra-precision hydrostatic bearing turntable of the present invention;

[0020] Figure 4 This is a schematic diagram of the water return structure of the ultra-precision hydrostatic bearing turntable of the present invention;

[0021] Figure 5 This is a schematic diagram of the pneumatic sealing structure of the ultra-precision hydrostatic bearing turntable of the present invention;

[0022] Figure 6 This is a schematic diagram of the main shaft in the ultra-precision hydrostatic bearing rotary table of the present invention;

[0023] Figure 7 This is an exploded structural diagram of the ultra-precision hydrostatic bearing turntable of the present invention;

[0024] The markings in the diagram are as follows: 1-Turntable base; 2-Copper ring; 3-Copper sleeve; 4-Shaft core; 5-End cover; 6-Sealing ring; 7-Water inlet pipe connector; 8-Water return pipe connector; 9-Air inlet pipe connector. Detailed Implementation

[0025] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the invention.

[0026] like Figures 1-5 As shown, the ultra-precision hydrostatic bearing turntable of the present invention includes a turntable base 1, a shaft core 4 and an end cover 5. The end cover 5 is located on the upper and lower sides of the turntable base 1, and the shaft core 4 is located inside the turntable base 1.

[0027] A copper sleeve 3 is installed on the inner circle of the turntable base 1, and the copper sleeve 3 is fixedly assembled with the base. A copper ring 2 is installed on the upper and lower surfaces of the turntable base 1, and the copper ring 2 is also fixedly connected to the turntable base 1. The copper sleeve assembly consisting of two copper rings 2 and a copper sleeve 3 forms a C-shaped structure with an outward opening around the inner circle edge of the turntable base 1.

[0028] The shaft core 4 is located inside the turntable base 1. The upper and lower sides of the shaft core 4 are fixedly connected to an end cap 5 by bolts, forming an I-shaped structure. The shaft core 4 can rotate synchronously with the end cap 5. The surfaces adjacent to the shaft core 4 and the copper sleeve 3, and the surfaces adjacent to the end cap 5 and the copper ring 2, are all clearance fits.

[0029] like Figure 3 As shown, a water inlet pipe connector 7 is provided on one side of the turntable base 1. The water inlet pipe connector 7 is connected to a water inlet channel opened inside the turntable base 1. The other end of the water inlet channel is connected to the gap between the shaft core 4 and the copper sleeve 3, and between the end cover 5 and the copper ring 2. The water inlet pipe connector 7 is connected to a water source to introduce ultra-precision water into the turntable base 1.

[0030] like Figure 4As shown, a return water pipe connector 8 is provided on one side of the turntable base 1. The return water pipe connector 8 communicates with a return water channel opened inside the turntable base 1. The other end of the return water channel is connected to the gap between the shaft core 4 and the copper sleeve 3, and between the end cover 5 and the copper ring 2. Ultra-precision water enters the gap inside the turntable through the water inlet channel and then exits through the water return channel, filling the gap between the copper sleeve assembly, the shaft core 4, and the end cover 5 with ultra-precision water, thus providing support for the rotation of the spindle components.

[0031] like Figure 5 As shown, an air inlet pipe connector 9 is provided on one side of the turntable base 1. The air inlet pipe connector 9 communicates with the air inlet channel opened inside the turntable base 1. The other end of the air inlet channel is connected to the groove between the end cover 5 and the surface of the copper ring 2, using compressed air to seal the gap between the end cover 5 and the copper ring 2. The groove on the surface of the copper ring 2 is not connected to the water channel.

[0032] A sealing ring 6 is provided on the upper surface of the lower end cover 5. The sealing ring 6 is located between the copper ring 2 and the lower end cover 5, making it difficult for the hydraulic medium to flow out and ensuring the sealing of the turntable.

[0033] The rotor mounting shaft is installed in the shaft core 4 and is driven by a torque motor, which can provide high torque to the turntable. A circular grating is set on the rotor mounting shaft, which, together with the circular grating reading head, can realize precise closed-loop control of the turntable rotation angle. It is easy to use and can be widely applied to various precision and ultra-precision CNC machine tools with rotary axes, such as lathes, grinding machines, four-axis machine tools, five-axis machine tools, and other equipment.

[0034] The present invention relates to an ultra-precision hydrostatic bearing turntable, on which copper rings 2 and copper sleeves 3 are installed. Compressed water that has undergone precision filtration is throttled through them, thereby supporting the rotation of the main shaft component.

[0035] The ultra-precision hydrostatic bearing turntable of this invention adopts a hydraulic bearing support structure. The turntable shaft core 4 assembly cooperates with the copper sleeve 3 assembly. The shaft core 4 is wrapped inside the copper sleeve 3 to ensure high precision of the turntable table surface rotation, as well as high load-bearing capacity and stable operation.

[0036] The ultra-precision hydrostatic bearing turntable of this invention adopts a pneumatic seal, which uses compressed air to seal the gap between the end cover 5 and the copper ring 2, and embeds a sealing ring 6 in the lower end cover 5 to make it difficult for the hydraulic medium to flow out, thus ensuring the seal of the turntable.

[0037] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A high-precision hydrostatic bearing turntable, characterized in that: The system includes a turntable base, with a copper sleeve installed on the inner circle of the turntable base. A copper ring is installed on each of the upper and lower surfaces of the turntable base. Both the copper sleeve and the copper ring are fixedly connected to the turntable base, forming a copper sleeve assembly. A shaft core is provided inside the base, and the shaft core is fixedly connected to the end cover. The surfaces adjacent to the shaft core and the copper sleeve, and the end cover and the copper ring, are all clearance fits. Ultra-precision water is filled between the copper sleeve assembly, the shaft core, and the end cover. A rotor mounting shaft is installed in the shaft core, and a circular grating is provided on the rotor mounting shaft. An air intake pipe connector is provided on one side of the turntable base, and the air intake pipe connector communicates with the air intake channel opened inside the turntable base. The other end of the air intake channel is connected between the end cover and the copper ring. The other end of the air intake channel is connected between the end cap and the groove on the surface of the copper ring, using compressed air to seal the gap between the end cap and the copper ring; the groove on the surface of the copper ring is not connected to the water passage. The copper sleeve assembly, consisting of two copper rings and a copper sleeve, forms a C-shaped structure with an outward opening around the inner edge of the turntable base. The upper and lower sides of the shaft are respectively fixedly connected to an end cap to form an I-shaped structure; A water inlet pipe connector is provided on one side of the turntable base. The water inlet pipe connector is connected to the water inlet channel opened inside the turntable base. The other end of the water inlet channel is connected to the gap between the shaft core and the copper sleeve, and between the end cover and the copper ring. A return water pipe joint is provided on one side of the turntable base. The return water pipe joint is connected to the return water channel opened inside the turntable base. The other end of the return water channel is connected to the gap between the shaft core and the copper sleeve, and between the end cover and the copper ring. A sealing ring is provided between the copper ring and the lower end cover to prevent the hydraulic medium from flowing out and to ensure the sealing of the turntable.

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