Numerical control rotary table

Abstract

The present application relates to the field of numerical control machine tool, specifically to a numerical control rotary table, which is composed of a box body, a table top, a worm wheel, a worm shaft, a movable gear plate, a fixed gear plate, a shaft, a piston, an outer spline sleeve and an inner spline ring. The table top is installed on the shaft and can move axially together with the shaft and the piston. When the table top moves axially upward, the movable gear plate and the fixed gear plate disengage, and the table top rotates under the drive of the gear, the worm wheel, the worm shaft, the outer spline sleeve and the inner spline ring. When the table top moves axially downward, the movable gear plate and the fixed gear plate engage, thereby ensuring the indexing accuracy of the rotary table.

Description

Technical Field

[0001] This invention relates to the field of CNC machine tools, specifically a CNC rotary table. Background Technology

[0002] This invention patent provides a CNC rotary table structure, which is used on machine tools such as machining centers and grinding machines. By using this CNC rotary table on the basis of the X, Y, and Z axes of the machine tool, the indexing function of the fourth axis can be realized.

[0003] Currently, there are two main types of transmission technology for CNC rotary tables: mechanical CNC rotary tables and torque motor direct-drive rotary tables.

[0004] The patented high-speed CNC rotary table with a fourth-axis torque motor (ZL201510245411.1) provides a high-speed CNC rotary table with a fourth-axis torque motor. It features high precision, high speed, fast response, good dynamic stiffness, small backlash, and continuous indexing capability, providing a fourth rotary axis for machining centers to achieve four-axis linkage. It can perform milling and mill-turn machining on complex surfaces. To measure and provide feedback on the rotary table's rotation angle, the high-speed CNC rotary table also includes an angle encoder. Furthermore, to ensure good positioning and maintain the rotary table at the required angle, the high-speed CNC rotary table also includes an end-face contact disc brake structure. This structure is suitable for light to medium loads and high-speed linkage machining conditions; however, the angle encoder is expensive. Its applicability is limited in heavy-load, indexing-only machining applications requiring high indexing accuracy.

[0005] Patent ZL201410274991.2 provides a rapid compensation device for the backlash of a dual-lead worm gear pair, which accurately sets the compensation amount and efficiently implements compensation to improve the accuracy and accuracy retention of CNC rotary tables. However, due to the sliding friction of the worm gear pair, wear will still increase the meshing clearance of the worm gear pair after a period of use, thus seriously affecting the accuracy of the CNC rotary table. While the patent provides a method for accurately setting the compensation amount and efficiently implementing compensation, it does not solve the problem of needing to perform periodic compensation.

[0006] A face gear is a precision connector that connects two components together, providing both centering and torque transmission without separation during operation. Face gears are primarily used in high-precision intermittent positioning and high-speed, high-torque transmission applications. Examples include intermittent positioning in machine tools, robot joints, and medical devices; centrifugal compressor rotors and impellers; gas turbine discs; aero-turbine engines; high-power engines; high-power gearboxes; propeller turbine blades in marine propulsion systems; and hollow shafts in high-speed locomotive bogies. They feature a large meshing area, long service life, high precision, good self-centering, and the ability to transmit large torques. They also simplify complex overall structures by dividing them into smaller, more streamlined components, facilitating design, manufacturing, and installation. Face gears are made of high-hardness, wear-resistant chromium-molybdenum alloy steel (SCM415H) that has undergone rigorous heat treatment, achieving a hardness of HRC58°, resulting in excellent wear resistance and a long service life. Face gears offer high positioning accuracy and repeatability, ensuring a positioning accuracy of ±2.5 seconds and a repeatability of ±1 second. The end face gear plate is ultra-precise and self-centering, with precise meshing. Through the meshing of convex and concave teeth, it can achieve precise automatic centering and has excellent interchangeability. Summary of the Invention

[0007] The purpose of this invention is to provide a CNC rotary table, and the specific technical solution is as follows:

[0008] A CNC rotary table includes: a housing, a table surface, a worm gear, a worm shaft, a movable gear plate, a fixed gear plate, a shaft, a piston, an external spline sleeve, and an internal spline ring. The specific structure is as follows:

[0009] The enclosure has a square structure with a square mounting flange on the bottom surface and an annular sealing flange on the top surface. The enclosure has a vertical inner hole with its axis perpendicular to the bottom surface from top to bottom, and a horizontal inner hole with its axis parallel to the bottom surface from left to right. The vertical inner hole has the following surfaces: a first inner hole surface, a first inner hole end face, a second inner hole surface, a second inner hole end face, a third inner hole surface, a third inner hole end face, a fourth outer circular surface, a fourth outer circular end face, a fifth inner hole surface, a sixth inner hole end face, and a seventh inner hole end face.

[0010] The outer circular surface of the fixed gear plate mates with the first inner hole surface of the housing and is fixed to the end face of the first inner hole of the housing by screws. The small outer circular surface of the first flange cover mates with the second inner hole surface of the housing and is fixed to the end face of the first inner hole of the housing by screws. The inner circular surface of the cross roller bearing mates with the fourth outer circular surface of the housing. The gasket is fixed to the end face of the third inner hole of the housing by screws, and the inner ring of the cross roller bearing is pre-tightened between the fourth outer circular surface of the housing and the gasket. The small outer circular surface of the second flange cover mates with the fifth inner hole surface of the housing and is fixed to the end face of the sixth inner hole of the housing by screws. The third flange cover is fixed to the end face of the seventh inner hole of the housing by screws.

[0011] The piston has a hollow stepped shaft structure. The large outer circle of the piston is installed in the cavity formed by the small end face of the first flange cover, the second inner hole face of the housing, and the end face of the second inner hole of the housing. The upper oil cavity is formed by the upper surface of the large outer circle of the piston, the second inner hole face of the housing, and the small end face of the first flange cover. The lower oil cavity is formed by the lower surface of the large outer circle of the piston, the second inner hole face of the housing, and the end face of the second inner hole of the housing. The upper and lower oil cavities are respectively connected to the hydraulic pipeline. When the lower oil cavity is supplied with oil, the piston moves upward. When the upper oil cavity is supplied with oil, the piston moves downward. An upper thrust roller bearing is installed on the upper end face of the piston, and a lower thrust roller bearing is installed on the lower end face of the piston. A needle roller bearing groove is opened on the upper end face of the piston, and an upper needle roller bearing is installed in the groove. A lower needle roller bearing groove is opened on the lower end face of the piston, and a lower needle roller bearing is installed in the groove.

[0012] The shaft has a hollow stepped shaft structure. The small outer diameter of the shaft is supported on the upper and lower needle roller bearings, and the lower end face of the large outer diameter of the shaft is supported on the upper thrust roller bearing. An external spline sleeve is fixed to the lower end face of the small outer diameter of the shaft by screws. There is a grinding pad between the upper end face of the external spline sleeve and the lower thrust roller bearing. The shaft can move up and down with the piston and can rotate relative to the piston.

[0013] The worktable has a recessed structure and is fixed to the upper end face of the shaft with screws. A movable gear plate is fixed to the stop of the worktable with screws. The movable gear plate meshes with the fixed gear plate installed on the housing. The outer circle of the movable gear plate and the outer edge of the worktable are inserted into the annular sealing flange of the housing. The worktable can move axially together with the shaft and piston. The worktable can rotate relative to the piston and housing together with the shaft. When the worktable moves axially upward, the movable gear plate and the fixed gear plate disengage. When the worktable moves axially downward, the movable gear plate and the fixed gear plate mesh. A radial T-slot is opened on the worktable.

[0014] The inner bore of the worm gear mates with the outer ring of the crossed roller bearing. The flange ring is fixed to the upper end face of the worm gear with screws, and the inner spline ring is fixed to the lower end face of the worm gear with screws. There is a grinding pad between the inner spline ring and the outer ring of the crossed roller bearing. The inner spline ring and the outer spline sleeve mesh with each other. When the outer spline sleeve moves upward axially together with the shaft and piston, the inner spline ring and the outer spline sleeve mesh with each other. When the outer spline sleeve moves downward axially together with the shaft and piston, the inner spline ring and the outer spline sleeve disengage.

[0015] The worm shaft is installed in a horizontal inner hole with its axis parallel to the bottom surface of the housing. The stepped end is supported on the housing by an angular contact bearing and a transition ring, while the cylindrical end is supported on the housing by a needle roller bearing. The axis of the worm shaft is parallel to the bottom surface of the housing and perpendicular to the worm wheel axis. The worm and worm wheel mesh for transmission. A large gear is installed at the tail of the cylindrical end through a shrink sleeve. The servo motor is installed on the side of the housing through a transition plate. A protective cover is installed on the side of the housing, and the protective cover and the side of the housing enclose the servo motor in a closed cavity. A small gear is installed on the output shaft of the servo motor through a shrink sleeve, and the small gear and the large gear mesh with each other.

[0016] Preferably, the side of the housing has a zero-position side hole, a rotation side hole, a locking side hole, and two oil holes. A zero-position switch is installed on the zero-position side hole, a rotation switch is installed on the rotation side hole, and a locking switch is installed on the locking side hole. The two oil holes are connected to the upper oil chamber and the lower oil chamber respectively, and a connector is installed on the side of the housing. A vernier is installed on the top surface of the housing, and an oil window is provided on the front of the housing. There are oil filling holes, worm gear cavity oil drain holes, and gear cavity oil drain holes on the front of the housing, which are plugged with plugs.

[0017] Preferably, a sensing ring is fixed to the lower end face of the outer spline sleeve by screws. The sensing ring moves up and down with the piston and shaft, generating sensing signals with the indexing switch and locking switch.

[0018] Preferably, a threaded block is installed on the flange ring, and the threaded block rotates together with the flange ring and the worm gear, generating an induction signal with the zero-position switch.

[0019] The advantages and beneficial effects of this invention are:

[0020] 1. This invention provides a CNC rotary table, which is composed of a housing, a worktable surface, a worm gear, a worm shaft, a moving gear plate, a fixed gear plate, a shaft, a piston, an external spline sleeve, and an internal spline ring. This rotary table is used on machine tools such as machining centers and grinding machines. Based on the X, Y, and Z axes, the CNC rotary table can realize the indexing function of the fourth axis.

[0021] 2. The present invention provides a CNC rotary table, wherein the output shaft of the servo motor drives the small gear to rotate through the expansion sleeve, the small gear and the large gear mesh with each other, and drives the worm shaft to rotate through the expansion sleeve installed on the tail end of the cylindrical end of the worm shaft, the worm on the worm shaft meshes with the worm wheel to drive the worm wheel to rotate, and the worm wheel drives the shaft to rotate through the inner spline ring and the outer spline sleeve, thereby driving the indexing rotation of the worktable surface;

[0022] 3. The present invention provides a CNC rotary table, wherein the table surface is fixed to the upper end face of the shaft by screws, and a movable gear plate is fixed to the stop of the table surface by screws. The movable gear plate meshes with the fixed gear plate installed on the housing to ensure the positioning accuracy of the rotary table.

[0023] 4. The present invention provides a CNC rotary table in which the piston, shaft, and outer spline sleeve move downward, the outer spline sleeve and inner spline ring disengage, the moving gear plate and the fixed gear plate mesh, and the shaft and outer spline sleeve can rotate circumferentially to compensate for the error that the worm wheel cannot reverse to drive the worm during positioning.

[0024] 5. This invention provides a CNC rotary table. An external spline sleeve and a sensing ring mounted on the external spline sleeve move up and down with the piston and shaft. The sensing ring generates sensing signals with a locking switch and a position switch to determine the locked and unlocked states of the worktable. During the rotation of the external spline sleeve, when a threaded block mounted on the retaining ring approaches a zero-position switch, the threaded block senses the zero-position switch and generates a sensing signal to determine the zero-point position of the worktable. The angular relationships of other positions relative to the zero-point position are read by a vernier mounted on the top surface of the housing. Attached Figure Description

[0025] Figure 1 This is an axonometric view of the present invention;

[0026] Figure 2 This is a side cross-sectional view of the present invention;

[0027] Figure 3 This is a side sectional view of the housing of the present invention;

[0028] Figure 4 This is a top cross-sectional view of the present invention;

[0029] Figure 5 The side view of the present invention without the protective cover;

[0030] Figure 6 This is a frontal cross-sectional view of the present invention.

[0031] In the diagram, 1. Workbench surface; 1.1 Workbench surface stop; 1.2 Outer edge of workbench surface; 1.3 T-slot; 2. Housing; 2.1 Bottom surface of housing; 2.2 Mounting flange; 2.3 Top surface of housing; 2.4 Annular sealing flange; 2.5 First inner hole surface of housing; 2.6 End face of first inner hole of housing; 2.7 Second inner hole surface of housing; 2.8 End face of second inner hole of housing; 2.9 Third inner hole surface of housing; 2.10 End face of third inner hole of housing; 2.11 Fourth outer circular surface of housing; 2.12 End face of fourth outer circular surface of housing; 2.13 Fifth inner hole surface of housing; 2.14 End face of sixth inner hole of housing; 2.15 Front of housing; 2.16 End face of seventh inner hole of housing; 2.17 Side of housing; 2.18 Zero-position side hole; 2. 19. Indexing side hole; 2.20. Locking side hole; 2.21. Oil hole; 2.22. Oil filling hole; 2.23. Worm gear cavity drain hole; 2.24. Gear cavity drain hole; 2.25. Vertical inner hole; 2.26. Horizontal inner hole; 3. Protective cover; 4. Fixed gear plate; 4.1. Outer cylindrical surface of fixed gear plate; 5. Screw; 6. First flange cover; 6.1. Small outer cylindrical surface of first flange cover; 7. Screw; 8. Crossed roller bearing; 8.1. Inner cylindrical surface of crossed roller bearing; 8.2. Inner ring of crossed roller bearing; 8.3. Outer ring of crossed roller bearing; 9. Gasket; 10. Screw; 11. Second flange cover; 11.1. Small outer cylindrical surface of second flange cover; 11.2. Small end face of first flange cover; 12. Screw; 13. Third flange cover; 14. Screw; 15. Piston; 15. 15.1 Piston's large outer diameter; 15.2 Upper surface of piston's large outer diameter; 15.3 Lower surface of piston's large outer diameter; 15.4 Upper oil chamber; 15.5 Lower oil chamber; 15.6 Upper end face of piston; 15.7 Lower end face of piston; 15.8 Upper needle roller bearing groove; 15.9 Lower needle roller bearing groove; 16 Upper thrust roller bearing; 17 Lower thrust roller bearing; 18 Upper needle roller bearing; 19 Lower needle roller bearing; 20 Shaft; 20.1 Small outer diameter surface of shaft; 20.2 Lower end face of shaft's large outer diameter; 20.3 Lower end face of shaft's small outer diameter; 20.4 Upper end face of shaft; 21 Screw; 22 External spline sleeve; 22.1 Upper end face of external spline sleeve; 22.2 Lower end face of external spline sleeve; 23 Grinding pad; 24 Screw; 25 Moving gear plate; 25 1. Outer cylindrical surface of the moving gear disc; 26. Worm gear; 26.1 Inner bore surface of the worm gear; 26.2 Upper end face of the worm gear; 26.3 Lower end face of the worm gear; 27. Side flange ring; 28. Screw; 29. ​​Inner spline ring; 30. Grinding pad; 31. Worm shaft; 31.1 Stepped end; 31.2 Cylindrical end; 31.3 Tail end of the cylindrical end; 31.4 Worm; 32. Angular contact bearing; 33. Transition ring; 34. Needle roller bearing; 35. Expansion sleeve; 36. Large gear; 37. Servo motor; 37.1 Output shaft; 38. Transition plate; 39. Expansion sleeve; 40. Small gear; 41. Zero position switch; 42. Indexing switch; 43. Locking switch; 44. Connector; 45. Vernier; 46. Oil window; 47. Plug; 48. Sensing ring; 49. Screw; 50. Threaded block; 51. Screw. Detailed Implementation

[0032] like Figure 1-6 As shown, this invention patent provides a CNC rotary table, mainly comprising: a housing 2, a worktable surface 1, a worm gear 26, a worm shaft 31, a moving gear disc 25, a fixed gear disc 4, a shaft 20, a piston 15, an external spline sleeve 22, and an internal spline ring 29. The specific structure is as follows:

[0033] The housing 2 has a square structure. The bottom surface 2.1 of the housing has a square mounting flange 2.2, and the top surface 2.3 of the housing has an annular sealing flange 2.4. The housing 2 has a vertical inner hole 2.25 with its axis perpendicular to the bottom surface 2.1 from top to bottom. The housing 2 has a horizontal inner hole 2.26 with its axis parallel to the bottom surface 2.1 from left to right. The vertical inner hole 2.25 has the following surfaces: first inner hole surface 2.5, first inner hole end face 2.6, second inner hole surface 2.7, second inner hole end face 2.8, third inner hole surface 2.9, third inner hole end face 2.10, fourth outer circular surface 2.11, fourth outer circular end face 2.12, fifth inner hole surface 2.13, sixth inner hole end face 2.14, and seventh inner hole end face 2.16.

[0034] The outer circular surface 4.1 of the fixed gear plate mates with the first inner bore surface 2.5 of the housing and is fixed to the first inner bore end face 2.6 of the housing by screws 5. The small outer circular surface 6.1 of the first flange cover 6 mates with the second inner bore surface 2.7 of the housing and is fixed to the first inner bore end face 2.6 of the housing by screws 7. The inner circular surface 8.1 of the crossed roller bearing 8 mates with the fourth outer circular surface 2.11 of the housing. The gasket 9 is fixed to the third inner bore end face 2.10 of the housing by screws 10, and the inner ring 8.2 of the crossed roller bearing is pre-tightened between the fourth outer circular end face 2.12 of the housing and the gasket 9. The small outer circular surface 11.1 of the second flange cover 11 mates with the fifth inner bore surface 2.13 of the housing and is fixed to the sixth inner bore end face 2.14 of the housing by screws 12. The third flange cover 13 is fixed to the seventh inner bore end face 2.16 of the housing by screws 14.

[0035] Piston 15 has a hollow stepped shaft structure. Piston 15 is installed into the third inner bore surface 2.9 of the housing. The large outer diameter 15.1 of the piston is installed in the cavity formed by the small end face 11.2 of the first flange cover, the second inner bore surface 2.7 of the housing, and the second inner bore end face 2.8 of the housing. The upper oil cavity 15.4 is formed by the upper outer diameter 15.1 of the piston, the second inner bore surface 2.7 of the housing, and the small end face 11.2 of the first flange cover. The lower oil cavity 15.5 is formed by the lower outer diameter 15.3 of the piston, the second inner bore surface 2.7 of the housing, and the second inner bore end face 2.8 of the housing. 15.4 and the lower oil chamber 15.5 are respectively connected to the hydraulic pipeline. When the lower oil chamber 15.5 supplies oil, the piston 15 moves upward. When the upper oil chamber 15.4 supplies oil, the piston 15 moves downward. An upper thrust roller bearing 16 is installed on the upper end face 15.6 of the piston, and a lower thrust roller bearing 17 is installed on the lower end face 15.7 of the piston. A needle roller bearing groove 15.8 is opened on the upper end face 15.6 of the piston, and an upper needle roller bearing 18 is installed in the groove. A lower needle roller bearing groove 15.9 is opened on the lower end face 15.7 of the piston, and a lower needle roller bearing 19 is installed in the groove.

[0036] Shaft 20 has a hollow stepped shaft structure. The small outer diameter 20.1 of the shaft is supported on the upper needle roller bearing 18 and the lower needle roller bearing 19. The large outer diameter lower end face 20.2 of the shaft is supported on the upper thrust roller bearing 16. An external spline sleeve 22 is fixed on the small outer diameter lower end face 20.3 of the shaft by screws 21. There is a grinding pad 23 between the upper end face 22.1 of the external spline sleeve and the lower thrust roller bearing 17. Shaft 20 can move up and down together with piston 15, and shaft 20 can rotate relative to piston 15.

[0037] The worktable 1 has a recessed structure. The worktable 1 is fixed to the upper end face 20.4 of the shaft by screws 24. A movable gear 25 is fixed to the worktable stop 1.1 by screws 51. The movable gear 25 meshes with the fixed gear 4 installed on the housing 2. The outer circular surface 25.1 of the movable gear 25 is inserted into the annular sealing flange 2.4 of the housing between the outer edge 1.2 of the worktable 20 and the outer circular surface 25.1 of the movable gear 25. The worktable 1 can move axially together with the shaft 20 and the piston 15. The worktable 1 can rotate relative to the piston 15 and the housing 2 together with the shaft 20. When the worktable 1 moves axially upward, the movable gear 25 and the fixed gear 4 disengage. When the worktable 1 moves axially downward, the movable gear 25 and the fixed gear 4 mesh. A radial T-shaped groove 1.3 is opened on the worktable 1.

[0038] The inner bore surface 26.1 of the worm gear mates with the outer ring 8.3 of the crossed roller bearing. The flange ring 27 is fixed to the upper end face 26.2 of the worm gear by screws 28. The inner spline ring 29 is fixed to the lower end face 26.3 of the worm gear by screws 28. There is a grinding pad 30 between the inner spline ring 29 and the outer ring 8.3 of the crossed roller bearing. The inner spline ring 29 and the outer spline sleeve 22 mesh with each other. When the outer spline sleeve 22 moves upward axially together with the shaft 20 and the piston 15, the inner spline ring 29 and the outer spline sleeve 22 mesh with each other. When the outer spline sleeve 22 moves downward axially together with the shaft 20 and the piston 15, the inner spline ring 29 and the outer spline sleeve 22 disengage.

[0039] The worm shaft 31 is installed in a horizontal inner hole 2.26 with its axis parallel to the bottom surface 2.1 of the housing. The stepped end 31.1 is supported on the housing 2 by an angular contact bearing 32 and a transition ring 33, and the cylindrical end 31.2 is supported on the housing 2 by a needle roller bearing 34. The axis of the worm shaft 31 is parallel to the bottom surface 2.1 of the housing and perpendicular to the axis of the worm wheel 26. The worm 31.4 and the worm wheel 26 mesh and drive each other. The tail end 31.3 of the cylindrical end is fitted with a large gear 36 through a shrink sleeve 35. The servo motor 37 is mounted on the side 2.17 of the housing through a transition plate 38. A protective cover 3 is installed on the side 2.17 of the housing. The protective cover 3 and the side 2.17 of the housing enclose the servo motor 37 in a closed cavity. The output shaft 37.1 of the servo motor 37 is fitted with a small gear 40 through a shrink sleeve 39. The small gear 40 and the large gear 36 mesh with each other.

[0040] The side 2.17 of housing 2 has a zero-position side hole 2.18, a rotation side hole 2.19, a locking side hole 2.20, and two oil holes 2.21. A zero-position switch 41 is installed on the zero-position side hole 2.18, a rotation switch 42 is installed on the rotation side hole 2.19, and a locking switch 43 is installed on the locking side hole 2.20. The two oil holes 2.21 are connected to the upper oil chamber 15.4 and the lower oil chamber 15.5 respectively, and a connector 44 is installed on the side 2.17 of housing 2. A vernier 45 is installed on the top surface 2.3 of housing 2. An oil window 46 is provided on the front 2.15 of housing 2. The front 2.15 of housing 2 has an oil filling hole 2.22, a worm gear cavity oil drain hole 2.23, and a gear cavity oil drain hole 2.24, which are blocked with a plug 47.

[0041] The lower end face 22.2 of the outer spline sleeve is fixed with a sensing ring 48 by screws 49. The sensing ring 48 moves up and down with the piston 15 and the shaft 20, generating sensing signals with the indexing switch 42 and the locking switch 43.

[0042] A threaded block 50 is installed on the flange ring 27. The threaded block 50 rotates together with the flange ring 27 and the worm gear 26, generating a sensing signal with the zero-position switch 41.

[0043] When oil is supplied to the upper oil chamber 15.4, the piston 15 and shaft 20 move downward, causing the worktable 1 and the moving gear plate 25 mounted on the worktable 1 to move downward. The moving gear plate 25 and the fixed gear plate 4 mesh. At the same time, the outer spline sleeve 22 and the sensing ring 48 mounted on the outer spline sleeve 22 move downward with the piston 15 and shaft 20. The sensing ring 48 generates a sensing signal with the locking switch 43, locking the worktable 1.

[0044] When oil is flowing through the oil chamber 15.5, the piston 15 and shaft 20 move upward, causing the worktable 1 and the moving gear plate 25 mounted on the worktable 1 to move upward. The moving gear plate 25 and the fixed gear plate 4 disengage. At the same time, the outer spline sleeve 22 and the sensing ring 48 mounted on the outer spline sleeve 22 move upward with the piston 15 and shaft 20. The sensing ring 48 generates a sensing signal with the indexing switch 42, and the worktable 1 is disengaged and locked. When the worktable 1 is in the disengaged locking state, the output shaft 37.1 of the servo motor 37 drives the pinion 40 to rotate via the expansion sleeve 39. The pinion 40 and the large gear 36 mesh with each other, and drive the worm shaft 31 to rotate via the expansion sleeve 35 installed on the tail end 31.3 of the cylindrical end of the worm shaft 31. The worm 31.4 on the worm shaft 31 meshes with the worm wheel 26, driving the worm wheel 26 to rotate. The worm wheel 26 drives the shaft 20 to rotate via the inner spline ring 29 and the outer spline sleeve 22, thus causing the worktable 1 to rotate in an indexing manner. During the rotation of the outer spline sleeve 22, when the threaded block 50 installed on the retaining ring 27 approaches the zero-position switch 41, the threaded block 50 senses the zero-position switch 41 and generates a sensing signal to determine the zero point position of the worktable 1. The angular relationship of other positions relative to the zero point position is read by the vernier 45 installed on the top surface 2.3 of the housing.

[0045] When oil is supplied to the upper oil chamber 15.4, the piston 15, shaft 20, and outer spline sleeve 22 move downwards. The outer spline sleeve 22 and inner spline ring 29 disengage, and the moving gear plate 25 and fixed gear plate 4 engage. The shaft 20 and outer spline sleeve 22 can rotate circumferentially to compensate for the error that the worm wheel cannot reverse to drive the worm during positioning. When oil is supplied to the lower oil chamber 15.5, the piston 15, shaft 20, and outer spline sleeve 22 move upwards. The outer spline sleeve 22 and inner spline ring 29 engage, and the moving gear plate 25 and fixed gear plate 4 disengage from the positioning state. The outer spline sleeve 22 and inner spline ring 29 engage for transmission.

[0046] Lubricating oil is injected through the oil filling hole 2.22 on the housing, and the amount of oil injected is read through the oil window 46 on the housing 2. The lubricating oil used in the worm gear cavity is discharged through the worm gear cavity drain hole 2.23, and the lubricating oil used in the gear cavity is discharged through the gear cavity drain hole 2.24. When the worktable is working normally, the oil filling hole 2.22, the worm gear cavity drain hole 2.23, and the gear cavity drain hole 2.24 are blocked with plug 47.

Claims

1. A CNC rotary table, characterized in that, The rotary table includes: a housing, a worktable surface, a worm gear, a worm shaft, a moving gear disc, a fixed gear disc, a shaft, a piston, an external spline sleeve, and an internal spline ring. The specific structure is as follows: The enclosure has a square structure with a square mounting flange on the bottom surface and an annular sealing flange on the top surface. The enclosure has a vertical inner hole with its axis perpendicular to the bottom surface from top to bottom, and a horizontal inner hole with its axis parallel to the bottom surface from left to right. The vertical inner hole has the following surfaces: a first inner hole surface, a first inner hole end face, a second inner hole surface, a second inner hole end face, a third inner hole surface, a third inner hole end face, a fourth outer circular surface, a fourth outer circular end face, a fifth inner hole surface, a sixth inner hole end face, and a seventh inner hole end face. The outer circular surface of the fixed gear plate mates with the first inner hole surface of the housing and is fixed to the end face of the first inner hole of the housing by screws. The small outer circular surface of the first flange cover mates with the second inner hole surface of the housing and is fixed to the end face of the first inner hole of the housing by screws. The inner circular surface of the cross roller bearing mates with the fourth outer circular surface of the housing. The gasket is fixed to the end face of the third inner hole of the housing by screws, and the inner ring of the cross roller bearing is pre-tightened between the fourth outer circular surface of the housing and the gasket. The small outer circular surface of the second flange cover mates with the fifth inner hole surface of the housing and is fixed to the end face of the sixth inner hole of the housing by screws. The third flange cover is fixed to the end face of the seventh inner hole of the housing by screws. The piston has a hollow stepped shaft structure. The large outer circle of the piston is installed in the cavity formed by the small end face of the first flange cover, the second inner hole face of the housing, and the end face of the second inner hole of the housing. The upper oil cavity is formed by the upper surface of the large outer circle of the piston, the second inner hole face of the housing, and the small end face of the first flange cover. The lower oil cavity is formed by the lower surface of the large outer circle of the piston, the second inner hole face of the housing, and the end face of the second inner hole of the housing. The upper and lower oil cavities are respectively connected to the hydraulic pipeline. When the lower oil cavity is supplied with oil, the piston moves upward. When the upper oil cavity is supplied with oil, the piston moves downward. An upper thrust roller bearing is installed on the upper end face of the piston, and a lower thrust roller bearing is installed on the lower end face of the piston. A needle roller bearing groove is opened on the upper end face of the piston, and an upper needle roller bearing is installed in the groove. A lower needle roller bearing groove is opened on the lower end face of the piston, and a lower needle roller bearing is installed in the groove. The shaft has a hollow stepped shaft structure. The small outer diameter of the shaft is supported on the upper and lower needle roller bearings, and the lower end face of the large outer diameter of the shaft is supported on the upper thrust roller bearing. An external spline sleeve is fixed to the lower end face of the small outer diameter of the shaft by screws. There is a grinding pad between the upper end face of the external spline sleeve and the lower thrust roller bearing. The shaft can move up and down with the piston and can rotate relative to the piston. The worktable has a recessed structure and is fixed to the upper end face of the shaft with screws. A movable gear plate is fixed to the stop of the worktable with screws. The movable gear plate meshes with the fixed gear plate installed on the housing. The outer circle of the movable gear plate and the outer edge of the worktable are inserted into the annular sealing flange of the housing. The worktable can move axially together with the shaft and piston. The worktable can rotate relative to the piston and housing together with the shaft. When the worktable moves axially upward, the movable gear plate and the fixed gear plate disengage. When the worktable moves axially downward, the movable gear plate and the fixed gear plate mesh. A radial T-slot is opened on the worktable. The inner bore of the worm gear mates with the outer ring of the crossed roller bearing. The flange ring is fixed to the upper end face of the worm gear with screws, and the inner spline ring is fixed to the lower end face of the worm gear with screws. There is a grinding pad between the inner spline ring and the outer ring of the crossed roller bearing. The inner spline ring and the outer spline sleeve mesh with each other. When oil is supplied to the upper oil chamber, the piston, shaft, and outer spline sleeve move downwards, the outer spline sleeve and the inner spline ring disengage, the moving gear plate and the fixed gear plate mesh, and the shaft and the outer spline sleeve can rotate circumferentially to compensate for the error that the worm gear cannot reverse to drive the worm during positioning. When oil is supplied to the lower oil chamber, the piston, shaft, and outer spline sleeve move upwards, the outer spline sleeve and the inner spline ring mesh, the moving gear plate and the fixed gear plate disengage, and the outer spline sleeve and the inner spline ring mesh for transmission. The worm shaft is installed in a horizontal inner hole with its axis parallel to the bottom surface of the housing. The stepped end is supported on the housing by an angular contact bearing and a transition ring, while the cylindrical end is supported on the housing by a needle roller bearing. The axis of the worm shaft is parallel to the bottom surface of the housing and perpendicular to the worm wheel axis. The worm and worm wheel mesh for transmission. A large gear is installed at the tail of the cylindrical end through a shrink sleeve. The servo motor is installed on the side of the housing through a transition plate. A protective cover is installed on the side of the housing, and the protective cover and the side of the housing enclose the servo motor in a closed cavity. A small gear is installed on the output shaft of the servo motor through a shrink sleeve, and the small gear and the large gear mesh with each other.

2. A CNC rotary table according to claim 1, characterized in that, The side of the housing has a zero-position side hole, a rotation side hole, a locking side hole, and two oil holes. A zero-position switch is installed on the zero-position side hole, a rotation switch is installed on the rotation side hole, and a locking switch is installed on the locking side hole. The two oil holes are connected to the upper oil chamber and the lower oil chamber respectively, and connectors are installed on the side of the housing. A vernier is installed on the top surface of the housing, and an oil window is provided on the front of the housing. There are oil filling holes, worm gear cavity oil drain holes, and gear cavity oil drain holes on the front of the housing, which are all plugged.

3. A CNC rotary table according to claim 1, characterized in that, A sensing ring is fixed to the lower end face of the external spline sleeve by screws. The sensing ring moves up and down with the piston and shaft, generating sensing signals with the indexing switch and locking switch.

4. A CNC rotary table according to claim 1, characterized in that, A threaded block is installed on the flange ring. The threaded block rotates together with the flange ring and the worm gear, generating an inductive signal with the zero-position switch.

Images