A rotary table combining hydrostatic flat bearing and rotary table bearing

Abstract

This invention relates to a rotary worktable combining a hydrostatic plane bearing and a rotary table bearing, comprising a housing and an annular worktable connected to the upper end of the housing. The worktable has an annular groove around its central hole. A motor is connected to the lower end of the housing, and the motor's spindle passes through the middle of the housing and the worktable, rotatably engaging with both. A support turntable, rotatably engaging with the annular groove of the worktable, is fixedly connected to the upper end of the spindle. An oil outlet hole is formed inside the annular groove of the worktable, and an oil inlet hole is formed at the bottom of the annular groove. An annular oil passage is formed inside the upper end of the housing, and an oil inlet channel with its outlet end connected to the annular oil passage is formed inside the side wall of the housing. Several vertical through grooves are distributed at intervals on the inner circumferential wall of the housing, and nozzles communicating with the oil outlet hole are provided at the upper ends of the vertical through grooves. This invention provides good lubrication, effectively ensuring a tight connection between the bearing and the worktable, reducing the coefficient of friction between the worktable and the housing, and improving the precision of the worktable's rotation.

Description

Technical Field

[0001] This invention relates to the field of rotary table technology, and in particular to a rotary table that combines a hydrostatic flat bearing and a turntable bearing. Background Technology

[0002] A rotary table combining hydrostatic flat bearings and rotary table bearings is used in precision and ultra-precision machine tools. The rotary table uses three types of bearings: rotary table bearings, hydrostatic bearings, and air bearings. These are mechanisms used to support and guide the rotation of workpieces. The working principle of hydrostatic bearings is the same as that of hydrostatic guideways. Lubricating oil with a certain pressure is introduced into the oil cavity on the surface of the hydrostatic support block through a throttle device, which forms a load-bearing oil film, so that the bearing support surfaces are in a state of pure liquid friction.

[0003] The static pressure plate provides back pressure through the lower floating porous throttling device, and the two together support the floating turntable, which can effectively improve the axial rotation accuracy of the turntable. However, the positioning mandrel still achieves radial limitation by contacting the inner wall of the connecting mandrel with its outer wall. During long-term use, there is still a slight radial wobble, which affects the rotation accuracy of the turntable. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a rotary worktable that combines a hydrostatic flat bearing and a rotary table bearing, which has good lubrication effect, reduces the friction coefficient between the worktable and the housing, and improves the precision of the worktable rotation.

[0005] This invention is achieved using the following scheme: a rotary worktable combining a hydrostatic plane bearing and a rotary table bearing, comprising a housing and an annular worktable connected to the upper end of the housing. The worktable has an annular groove around its central hole. A motor is connected to the lower end of the housing. The main shaft of the motor passes through the middle of the housing and the worktable and rotates with both. A support turntable that rotates with the annular groove of the worktable is fixedly connected to the upper end of the main shaft. An oil outlet hole is provided inside the annular groove of the worktable, and an oil inlet hole is provided at the bottom of the annular groove. An annular oil passage is provided inside the upper end of the housing. An oil inlet channel with an oil outlet end connected to the annular oil passage is provided inside the side wall of the housing. Several vertical through grooves are distributed at intervals on the inner peripheral wall of the housing. A nozzle connected to the oil outlet hole is provided at the upper end of each vertical through groove.

[0006] Furthermore, the oil inlet end of the oil inlet channel is connected to a refueling pipe, and a filter is connected to the refueling pipe.

[0007] Furthermore, the upper end face of the casing is provided with a first connecting hole corresponding to and communicating with the nozzle and a second connecting hole communicating with the annular oil passage. The second connecting hole is connected with the oil inlet hole, and the oil outlet hole is connected with the first connecting hole through the oil outlet channel on the worktable.

[0008] Furthermore, the lower end of the vertical through groove is provided with a return port, and an oil collecting ring is fixedly connected to the outer side of the lower end of the casing. An oil return concentrator is opened on the inner side of the oil collecting ring. The return port is connected to the oil return concentrator through several connecting grooves inside the lower end of the casing. A concentrated oil outlet is opened on the side of the oil collecting ring and is connected to the oil return concentrator.

[0009] Furthermore, a floating turntable is fixedly connected to the upper end of the supporting turntable.

[0010] Furthermore, an annular cover plate is provided on the upper side of the worktable, and a first sealing ring is provided between the support turntable and the cover plate, with the outer side of the first sealing ring tightly attached to the annular groove periphery of the worktable; a second sealing ring is provided on the inner side of the lower end of the housing, with the inner side of the second sealing ring tightly attached to the outer side of the spindle.

[0011] Compared with the prior art, the present invention has the following beneficial effects: The rotary worktable of the present invention, which combines hydrostatic plane bearing and rotary table bearing, has good lubrication effect, which can effectively make the bearing of the worktable tightly connected with the worktable, reduce the friction coefficient between the worktable and the outer shell, and improve the precision of the rotation of the worktable. This solves the problem that the positioning mandrel still achieves radial limit by contacting the inner wall of the connecting mandrel through its outer wall, and there is still a slight radial wobble during long-term use, which affects the rotation accuracy of the rotary table.

[0012] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through specific embodiments and related drawings. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0014] Figure 2 This is a schematic diagram of the floating turntable structure according to an embodiment of the present invention;

[0015] Figure 3 This is a schematic diagram of the motor structure according to an embodiment of the present invention;

[0016] Figure 4 This is a schematic diagram of the cross-sectional structure of the casing according to an embodiment of the present invention;

[0017] Figure 5 This is a schematic diagram of the second connecting hole structure according to an embodiment of the present invention;

[0018] Figure 6 This is a schematic diagram of the nozzle location in an embodiment of the present invention;

[0019] The following are the labels in the diagram: 1. Housing; 2. Worktable; 3. Motor; 4. Spindle; 5. Support turntable; 6. First sealing ring; 7. Floating turntable; 8. Oil outlet; 9. Oil inlet; 10. Second sealing ring; 11. Oil inlet channel; 12. Filter; 13. Oil filling pipe; 14. Nozzle; 15. First connecting hole; 16. Return port; 17. Return oil collection groove; 18. Oil collection ring; 19. Centralized oil outlet; 20. Baffle plate; 21. Second connecting hole; 22. Annular oil passage. Detailed Implementation

[0020] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0021] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0022] like Figures 1-6 As shown, a rotary worktable combining a hydrostatic plane bearing and a rotary table bearing includes a housing 1 and an annular worktable 2 connected to the upper end of the housing. The upper end of the housing 1 is a hollow cylinder, and the lower end of the housing 1 is a flat annular body. An annular groove is formed around the central hole of the worktable 2. A motor 3 is connected to the lower end of the housing. The main shaft 4 of the motor 3 passes through the middle of the housing and the worktable and rotates with both. A support turntable 5 is fixedly connected to the upper end of the main shaft 4 and rotates with the annular groove of the worktable 2. An oil outlet hole 8 is formed inside the annular groove of the worktable 2, and an oil inlet hole 9 is formed at the bottom of the annular groove. An annular oil passage 22 is formed inside the upper end of the housing 1. An oil inlet channel 11 with an oil outlet end connected to the annular oil passage is formed inside the side wall of the housing 1. Several vertical through grooves are distributed at intervals on the inner peripheral wall of the housing. A nozzle 14 connected to the oil outlet hole is formed at the upper end of the vertical through groove. The lubricating oil passes through the oil inlet channel 11, the annular oil passage 22, the oil inlet hole 9, the oil outlet hole 8, the nozzle 14 and the vertical through groove in sequence. The lubricating oil enters the worktable through the oil inlet hole 9 and enters the housing 1 through the nozzle, thereby achieving lubrication of the spindle and the support turntable 5.

[0023] In this embodiment, the oil inlet end of the oil inlet channel 11 is connected to a filling pipe 13, and a filter 12 is connected to the filling pipe 13 to filter the lubricating oil entering the casing 1.

[0024] In this embodiment, the upper end face of the housing 1 is provided with a first connecting hole 15 corresponding to and communicating with the nozzle 14 and a second connecting hole 21 communicating with the annular oil passage 22. The second connecting hole 21 is connected with the oil inlet hole 9. The lubricating oil in the annular oil passage 22 enters the oil inlet hole 9 through the second connecting hole 21. The oil outlet hole 8 is connected to the first connecting hole 15 through the oil outlet channel (not shown in the figure) on the worktable 2. The upper end of the oil outlet channel is connected to the oil outlet hole 8. It first extends downward from the side of the worktable, then extends from the bottom of the worktable to the middle, and then penetrates the bottom surface of the worktable to communicate with the first connecting hole 15. Therefore, the nozzle 14 is connected to the oil outlet hole 8 through the first connecting hole 15 and the oil outlet channel.

[0025] In this embodiment, a return port 16 is provided at the lower end of the vertical through groove, and an oil collecting ring 18 is fixedly connected to the outer side of the lower end of the casing 1. An oil return concentrator 17 is provided on the inner side of the oil collecting ring 18. The return port 16 is connected to the oil return concentrator 17 through several connecting grooves (not shown in the figure) inside the lower end of the casing 1. The connecting grooves are arranged radially, and the number of connecting grooves is the same as that of the return port 16 and they are connected one by one. A concentrated oil outlet 19 is provided on the side of the oil collecting ring 18 and is connected to the oil return concentrator 17. This facilitates the flow of lubricating oil through the casing 1 and the worktable 2 from the oil return concentrator 17 and the concentrated oil outlet 19. The concentrated oil outlet 19 and the oil filling pipe 13 can be connected to external equipment to realize the circulation of lubricating oil.

[0026] In this embodiment, a floating turntable 7 is fixedly connected to the upper end of the supporting turntable 5.

[0027] In this embodiment, an annular cover plate is provided on the upper side of the worktable 2, and a first sealing ring 6 is provided between the support turntable 5 and the cover plate. The outer side of the first sealing ring 6 is in close contact with the annular groove periphery of the worktable 2, which has the effect of sealing between the worktable 2 and the support turntable 5 to prevent impurities from entering the interior of the worktable 2. A second sealing ring 10 is provided on the inner side of the lower end of the housing, and the inner side of the second sealing ring 10 is in close contact with the outer side of the spindle 4, which has the effect of sealing between the housing 1 and the spindle 4 to prevent lubricating oil from flowing out. A partition 20 is formed between two adjacent vertical through grooves, and the partition 20 is in contact with the outer side of the spindle 4.

[0028] Working process: During use, the device is powered by an external power source. When the motor 3 drives the support turntable 5 to rotate via the main shaft 4, oil is supplied to the inside of the housing 1 through the oil filling pipe 13. The lubricating oil enters the filter 12 from the inside of the oil filling pipe 13. The filter 12 filters the lubricating oil entering the housing 1. The lubricating oil then enters the oil inlet channel 11 on the inner side of the housing 1 from the filter 12. From the oil inlet channel 11, it enters the annular oil passage 22. The lubricating oil then enters the worktable from the annular oil passage 22 through the second connecting hole 21 and the oil inlet hole 9, thereby reducing the friction between the support turntable 5 and the worktable 2. Then, the lubricating oil flows from the inside of the worktable 2 through the oil outlet hole 8, the oil outlet channel, and the first connecting hole 15 to the nozzle 14. It is then sprayed from the nozzle 14 into the vertical through groove inside the housing, which lubricates the main shaft 4, the housing 1, and the partition 20. Finally, the lubricating oil flows into the return oil collection tank 17 through the return port 16 and then flows out from the collection oil outlet 19.

[0029] During use, the hydrostatic rotary table of this invention pressurizes the oil inlet channel with lubricating oil through the oil filling pipe, allowing the lubricating oil to enter the worktable and the outer shell sequentially. Simultaneously, the lubricated oil flows back from the inside of the shell to the oil collection ring, and then flows out from the centralized oil outlet 19. This effectively ensures a tight connection between the bearings and the worktable, reduces the coefficient of friction between the worktable and the outer shell, and improves the precision of the worktable's rotation. This solves the problem that the positioning mandrel still achieves radial limiting through its outer wall contacting the inner wall of the connecting mandrel, and that even after long-term use, there is still slight radial wobble, affecting the rotational accuracy of the rotary table.

[0030] Unless otherwise stated, if any of the technical solutions disclosed in this invention specify a numerical range, then the disclosed numerical range is a preferred numerical range. Anyone skilled in the art should understand that the preferred numerical range is merely one among many feasible numerical values ​​that has a more obvious or representative technical effect. Because there are many numerical values, it is impossible to list them all. Therefore, this invention discloses only some numerical values ​​to illustrate the technical solutions of this invention. Furthermore, the numerical values ​​listed above should not constitute a limitation on the scope of protection of this invention.

[0031] If this invention discloses or relates to mutually fixedly connected components or structural parts, then, unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured in one piece using a casting process) (except where it is obviously impossible to use an integral molding process).

[0032] In addition, unless otherwise stated, the terms used in any of the technical solutions disclosed in this invention to indicate positional relationships or shapes include states or shapes that are similar to, close to, or approximate with those states or shapes.

[0033] Any component provided by this invention can be assembled from multiple individual components or can be a single component manufactured by a one-piece molding process.

[0034] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A rotary worktable combining a hydrostatic flat bearing and a rotary table bearing, characterized in that: The device includes a housing and an annular worktable connected to the upper end of the housing. The worktable has an annular groove around its central hole. A motor is connected to the lower end of the housing. The motor's spindle passes through the housing and the worktable and rotates with both. A support turntable, rotating with the annular groove of the worktable, is fixedly connected to the upper end of the spindle. An oil outlet is provided inside the annular groove of the worktable, and an oil inlet is provided at the bottom of the groove. An annular oil passage is provided inside the upper end of the housing. An oil inlet channel, with its outlet end connected to the annular oil passage, is provided inside the side wall of the housing. Several vertical through slots are distributed at intervals on the inner circumferential wall of the housing. The upper end of the groove is provided with a nozzle that communicates with the oil outlet; the upper end face of the casing is provided with a first connecting hole that communicates with the nozzle and a second connecting hole that communicates with the annular oil passage. The second connecting hole is connected with the oil inlet. The oil outlet is connected with the first connecting hole through the oil outlet channel on the worktable. The lower end of the vertical groove is provided with a return port. An oil collecting ring is fixedly connected to the outer side of the lower end of the casing. An oil return collection groove is provided on the inner side of the oil collecting ring. The return port is connected to the oil return collection groove through several connecting grooves inside the lower end of the casing. A centralized oil outlet is provided on the side of the oil collecting ring that communicates with the oil return collection groove.

2. The rotary table combining a hydrostatic plane bearing and a rotary table bearing according to claim 1, characterized in that: The oil inlet channel is connected to an oil filling pipe, and a filter is connected to the oil filling pipe.

3. The rotary worktable combining a hydrostatic plane bearing and a rotary table bearing according to claim 1, characterized in that: The upper end of the support turntable is fixedly connected to a floating turntable.

4. The rotary table combining a hydrostatic plane bearing and a rotary table bearing according to claim 1, characterized in that: An annular cover plate is provided on the upper side of the worktable, and a first sealing ring is provided between the support turntable and the cover plate. The outer side of the first sealing ring is in close contact with the annular groove periphery of the worktable. A second sealing ring is provided on the inner side of the lower end of the housing, and the inner side of the second sealing ring is in close contact with the outer side of the spindle.

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