Bearing static pressure rotary table

Abstract

The utility model provides a bearing static pressure rotary table, and belongs to the technical field of machinery. The problem that an existing rotary table is not stable in work is solved. The bearing static pressure rotary table comprises a cylindrical machine base and a workbench horizontally arranged above the machine base, a motor is fixed in the lower end of the machine base, the upper end of a main shaft of the motor is fixedly connected with the workbench, the upper side of the machine base and the lower side of the workbench are fixedly connected with an outer ring and an inner ring respectively, and a static pressure sleeve is arranged between the outer ring and the inner ring. An annular upper hydraulic groove is formed between the top wall of the static pressure sleeve and the workbench, an annular lower hydraulic groove is formed between the inner wall of the static pressure sleeve and the inner ring, and a first oil inlet channel and a second oil inlet channel which enable the upper hydraulic groove and the lower hydraulic groove to be communicated with the outside respectively are formed between the static pressure sleeve and the outer ring. An upper rolling bearing is arranged between the positioning ring and the upper end of the spindle, and the inner ring and the outer ring of the upper rolling bearing are fixedly connected with the spindle and the positioning ring respectively. The bearing static pressure rotary table is stable in operation.

Description

Technical Field

[0001] This utility model belongs to the field of mechanical technology and relates to a hydrostatic turntable, particularly a bearing hydrostatic turntable. Background Technology

[0002] A hydrostatic rotary table is a rotary worktable component used in vertical lathes. The worktable plane is placed horizontally and can rotate continuously and smoothly at a uniform speed.

[0003] An existing hydrostatic rotary table, such as the combined hydrostatic rotary table previously proposed by the applicant (application number: 202323035113.9), includes a vertically arranged main shaft and a cylindrical outer shell sleeved around the main shaft. A circular sleeve is provided between the main shaft and the outer shell, and the circular sleeve is sleeved on the main shaft and supports the main shaft upwards. The top wall and inner side wall of the circular sleeve form annular oil grooves with the outer wall of the main shaft. An annular oil guide cavity is formed between the upper outer wall of the circular sleeve, the main shaft, and the outer shell. An annular oil return cavity is formed between the bottom wall of the circular sleeve, the main shaft, and the outer shell. An oil inlet hole and an oil return hole communicating with the oil return cavity are provided on the side wall of the outer shell. An oil inlet channel communicating with the annular oil groove and an oil return channel communicating with the oil guide cavity and the oil return cavity are formed inside the circular sleeve. The circular sleeve is characterized in that the outer edge of the bottom surface of the circular sleeve is annular and presses against the inner wall of the outer shell, and the support surface is offset from the position of the oil return cavity. The lower end of the main shaft is rotatably supported on the outer shell by a bearing.

[0004] In the aforementioned rotary table, the side and top walls of the sleeve are all clearance-fitted with the main shaft, and there are several extremely narrow gaps along the circumference of the sleeve. During operation, hydraulic oil is injected into the gaps to suspend and support the main shaft. However, when the hydraulic oil pressure is insufficient, the sleeve and the main shaft may seize up, affecting the operation of the rotary table. Utility Model Content

[0005] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a bearing hydrostatic rotary table with stable operation.

[0006] The objective of this utility model can be achieved through the following technical solution: A bearing hydrostatic turntable includes a cylindrical base and a worktable horizontally arranged above the base. A motor is fixed inside the lower end of the base, and the upper end of the motor's main shaft is fixed to the worktable. An outer ring and an inner ring are fixed to the upper side of the base and the lower side of the worktable, respectively. A hydrostatic sleeve is provided between the outer ring and the inner ring. An annular upper hydraulic groove is formed between the top wall of the hydrostatic sleeve and the worktable. An annular lower hydraulic groove is formed between the inner wall of the hydrostatic sleeve and the inner ring. An oil inlet channel one and an oil inlet channel two are formed between the hydrostatic sleeve and the outer ring, respectively connecting the upper hydraulic groove and the lower hydraulic groove to the outside. The feature is that a positioning ring coaxial with the base is formed on the top wall of the base. The positioning ring is located between the inner ring and the main shaft. An upper rolling bearing is provided between the positioning ring and the upper end of the main shaft, and the inner ring and outer ring of the upper rolling bearing are fixed to the main shaft and the positioning ring, respectively.

[0007] During use, hydraulic oil enters the upper hydraulic groove and the lower hydraulic groove through oil inlet channel one and oil inlet channel two respectively, so that an oil film is formed between the hydrostatic sleeve and the worktable and the inner ring, realizing the suspension operation of the worktable and improving working stability and accuracy.

[0008] A bearing is installed between the upper end of the spindle and the positioning ring of the machine base to provide rigid support for the worktable. This ensures that there is always a clearance between the hydrostatic sleeve and the worktable and inner ring, thereby preventing contact seizure due to insufficient hydraulic supply and ensuring that the hydrostatic turntable maintains stable operation.

[0009] In the aforementioned bearing hydrostatic turntable, the inner wall of the base has a horizontally arranged annular surface, and the outer wall of the upper end of the main shaft is formed with an annular limiting seat. The top wall of the inner ring and the bottom wall of the outer ring of the upper rolling bearing press against the limiting seat and the annular surface, respectively, to stabilize the limiting bearing in the axial direction and further improve the stability of the turntable operation.

[0010] In the aforementioned bearing hydrostatic rotary table, a retaining ring is horizontally positioned between the locating ring and the worktable. The retaining ring is sleeved around the main shaft and fixed to the top wall of the locating ring. A raised ring is formed on the bottom wall of the retaining ring, pressing against the top wall of the outer ring. The raised ring further enhances the axial positioning effect of the bearing, thereby further improving the stability of the rotary table's operation.

[0011] In the aforementioned bearing hydrostatic rotary table, the upper end of the retaining ring forms a seal with the worktable via an oil seal, and the lower end of the retaining ring forms a seal with the positioning ring. This design effectively prevents hydraulic oil leakage towards the spindle, ensuring stable operation of the rotary table.

[0012] The retaining ring serves both as an axial limiter for the upper rolling bearing and as a means to prevent hydraulic oil leakage. In this application, the retaining ring has a dual function, simplifying the structure and facilitating assembly.

[0013] In the aforementioned bearing hydrostatic turntable, the lower end of the retaining ring forms a seal with the positioning ring through a sealing ring.

[0014] Compared with existing technologies, this bearing hydrostatic rotary table has the following advantages:

[0015] 1. A bearing is installed between the upper end of the spindle and the positioning ring of the machine base to provide rigid support for the worktable, ensuring that there is always a clearance between the hydrostatic sleeve and the worktable and the inner ring, thereby preventing contact seizure due to insufficient hydraulic supply and ensuring that the hydrostatic turntable maintains stable operation.

[0016] 2. The retaining ring is used both for axial positioning of the upper rolling bearing and for preventing hydraulic oil leakage. In this application, the retaining ring has a dual function, which simplifies the structure and facilitates assembly. Attached Figure Description

[0017] Figure 1 This is a side view of the bearing hydrostatic turntable.

[0018] Figure 2 This is a cross-sectional schematic diagram of a bearing hydrostatic turntable.

[0019] Figure 3 yes Figure 2 Enlarged diagram of point A in the middle.

[0020] Figure 4 yes Figure 2 Sectional view at point AA.

[0021] In the diagram, 1. Machine base; 1a. Positioning ring; 1b. Annular surface; 2. Worktable; 3. Motor; 3a. Spindle; 3b. Limit seat; 4. Lower rolling bearing; 5. Outer ring; 5a. Oil inlet hole one; 5b. Oil inlet hole two; 6. Inner ring; 7. Hydrostatic sleeve; 7a. Annular groove one; 7b. Oil guide hole one; 7c. Annular groove two; 7d. Oil guide hole two; 8. Upper hydraulic groove; 9. Lower hydraulic groove; 10. Oil return chamber; 11. Upper rolling bearing; 12. Retaining ring; 12a. Convex ring; 13. Oil seal one; 14. Sealing ring one. Detailed Implementation

[0022] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0023] like Figure 1 and Figure 2 As shown, this bearing hydrostatic turntable includes a cylindrical base 1 and a worktable 2 horizontally arranged above the base 1, and the base 1 and the worktable 2 are coaxially arranged.

[0024] in,

[0025] A motor 3 is fixed inside the lower end of the base 1. Specifically, the motor 3 includes a housing and a spindle 3a vertically mounted inside the housing, with the housing, spindle 3a, and base 1 coaxially arranged. The lower end of the housing extends out of the base 1 and is fixed to the base 1 by screws. The upper end of the spindle 3a extends out of the housing and is fixed to the worktable 2. In the actual product, the lower end of the spindle 3a is rotatably connected to the housing via a lower rolling bearing 4.

[0026] like Figures 2 to 4As shown, an outer ring 5 and an inner ring 6 are fixedly connected to the upper side of the machine base 1 and the lower side of the worktable 2, respectively. The outer ring 5, inner ring 6, and machine base 1 are coaxially arranged, with the inner ring 6 located inside the outer ring 5. A hydrostatic sleeve 7 is provided between the inner ring 6 and the outer ring 5, and the hydrostatic sleeve 7 is coaxial with the outer ring 5 and the two are fixedly connected. Among them, an annular upper hydraulic groove 8 is formed between the top wall of the hydrostatic sleeve 7 and the worktable 2, and an annular lower hydraulic groove 9 is formed between the inner wall of the hydrostatic sleeve 7 and the inner ring 6. Both the upper hydraulic groove 8 and the lower hydraulic groove 9 are coaxially arranged with the machine base 1. In the actual product, the upper hydraulic groove 8 and the lower hydraulic groove 9 are both composed of a ring of circumferentially continuously alternating wide and narrow grooves. The narrow grooves are extremely narrow to provide relatively stable axial and radial support for the worktable 2.

[0027] A hydrostatic sleeve 7 and an outer ring 5 form an upper hydraulic groove 8 and a lower hydraulic groove 9 that connect to external oil inlet channels one and two, respectively. Specifically, as... Figure 3 and Figure 4 As shown, the first oil inlet channel includes an oil inlet hole 5a penetrating the outer ring 5, an annular groove 7a formed on the outer wall of the hydrostatic sleeve 7, and a ring of guide holes 7b formed inside the side wall of the hydrostatic sleeve 7. The annular groove 7a is coaxially arranged with the hydrostatic sleeve 7. The number of wide grooves in the upper hydraulic groove 8 is the same as the number of guide holes 7b, and both ends of the guide holes 7b are connected to the annular groove 7a and the corresponding wide groove, respectively. The oil inlet hole 5a is connected to the aforementioned annular groove 7a. The second oil inlet channel includes an oil inlet hole 2 5b penetrating the outer ring 5, an annular groove 2 7c formed on the outer wall of the hydrostatic sleeve 7, and a ring of guide holes 2 7d formed inside the side wall of the hydrostatic sleeve 7. The annular groove 2 7c is coaxially arranged with the hydrostatic sleeve 7, and one end of the oil inlet hole 2 5b is connected to the annular groove 2 7c. The number of wide grooves in the lower hydraulic groove 9 is the same as the number of guide holes 2 7d, and both ends of the guide holes 2 7d are connected to the annular groove 2 7c and the corresponding wide groove, respectively. In the actual product, a return oil cavity 10 is formed between the lower end of the hydrostatic sleeve 7 and the base 1, the lower hydraulic groove 9 is located above the return oil cavity 10, and the outer ring 5 is also provided with a return oil hole that connects to the return oil cavity 10.

[0028] To further explain, an O-ring is provided between the hydrostatic sleeve 7 and the outer ring 5 to form a seal between them. There are three O-rings, which are distributed along the axial direction of the outer ring 5. The aforementioned annular groove 7a and annular groove 7c are both located between two of the O-rings.

[0029] like Figure 2 and Figure 3As shown, a positioning ring 1a, coaxial with the machine base 1, is formed on the top wall of the machine base 1. The positioning ring 1a is located between the inner ring 6 and the main shaft 3a. An upper rolling bearing 11 is provided between the positioning ring 1a and the upper end of the main shaft 3a. The upper rolling bearing 11 is an existing product, including an inner ring and an outer ring, and the inner ring and outer ring of the upper rolling bearing 11 are respectively fixed to the main shaft 3a and the positioning ring 1a. Preferably, the inner ring and outer ring of the upper rolling bearing 11 are fixed to the main shaft 3a and the positioning ring 1a respectively by an interference fit.

[0030] During use, hydraulic oil enters the upper hydraulic groove 8 and the lower hydraulic groove 9 through the first and second oil inlet channels respectively, so that an oil film is formed between the hydrostatic sleeve 7, the worktable 2 and the inner ring 6, realizing the suspension operation of the worktable 2 and improving working stability and accuracy.

[0031] A bearing is installed between the upper end of the spindle 3a and the positioning ring 1a of the base 1 to provide rigid support for the worktable 2, ensuring that there is always a fit clearance between the hydrostatic sleeve 7 and the worktable 2 and the inner ring 6, thereby preventing contact seizure due to insufficient hydraulic supply and ensuring that the hydrostatic turntable maintains stable operation.

[0032] To further explain, the inner wall of the base 1 has a horizontally arranged annular surface 1b, and the annular surface 1b is coaxial with the base 1. An annular limiting seat 3b is formed on the outer wall of the upper end of the main shaft 3a. The limiting seat 3b is coaxial with the main shaft 3a, and the top wall of the inner ring and the bottom wall of the outer ring of the upper rolling bearing 11 press against the limiting seat 3b and the annular surface 1b respectively, so as to stabilize the limiting bearing in the axial direction and further improve the stability of the turntable operation.

[0033] To prevent hydraulic oil leakage, such as Figure 2 and Figure 3 As shown, the top wall of the outer ring 5 is sealed to the worktable 2 via oil seal 2; the bottom wall of the outer ring 5 is sealed to the machine base 1 via sealing ring 2; and the top wall of the inner ring 6 is sealed to the worktable 2 via sealing ring 3. Further, there is a gap between the bottom wall of the inner ring 6 and the machine base 1. A retaining ring 12 is horizontally positioned between the positioning ring 1a and the worktable 2. The retaining ring 12 is fitted over the spindle 3a and fixed to the top wall of the positioning ring 1a. The upper end of the retaining ring 12 is sealed to the worktable 2 via oil seal 13, and the lower end of the retaining ring 12 is sealed to the positioning ring 1a. This design effectively prevents hydraulic oil leakage towards the spindle 3a, ensuring stable operation of the turntable. Preferably, the lower end of the retaining ring 12 is sealed to the positioning ring 1a via sealing ring 14.

[0034] To further explain, a convex ring 12a is formed on the bottom wall of the retaining ring 12. The convex ring 12a is coaxially arranged with the retaining ring 12 and presses against the top wall of the outer ring. The convex ring 12a can further enhance the axial positioning effect of the bearing, thereby further enhancing the stability of the turntable operation.

[0035] The retaining ring 12 serves both as an axial limit for the upper rolling bearing 11 and as a means to prevent hydraulic oil leakage. In this application, the retaining ring 12 has a dual function, which simplifies the structure and facilitates assembly.

[0036] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A bearing hydrostatic rotary table, comprising a cylindrical base (1) and a worktable (2) horizontally disposed above the base (1), wherein a motor (3) is fixedly disposed at the lower end of the base (1), and the upper end of the main shaft (3a) of the motor (3) is fixedly connected to the worktable (2), an outer ring (5) and an inner ring (6) are respectively fixedly connected to the upper side of the base (1) and the lower side of the worktable (2), a hydrostatic sleeve (7) is provided between the outer ring (5) and the inner ring (6), an annular upper hydraulic groove (8) is formed between the top wall of the hydrostatic sleeve (7) and the worktable (2), an annular lower hydraulic groove (9) is formed between the inner wall of the hydrostatic sleeve (7) and the inner ring (6), and an oil inlet channel one and an oil inlet channel two are formed between the hydrostatic sleeve (7) and the outer ring (5) to connect the upper hydraulic groove (8) and the lower hydraulic groove (9) to the outside, respectively, characterized in that, A positioning ring (1a) coaxial with the machine base (1) is formed on the top wall of the machine base (1). The positioning ring (1a) is located between the inner ring (6) and the main shaft (3a). An upper rolling bearing (11) is provided between the positioning ring (1a) and the upper end of the main shaft (3a). The inner ring and outer ring of the upper rolling bearing (11) are respectively fixed to the main shaft (3a) and the positioning ring (1a).

2. The bearing hydrostatic rotary table according to claim 1, characterized in that, The aforementioned base (1) has a horizontally arranged annular surface (1b) on its inner wall, and a ring-shaped limiting seat (3b) is formed on the upper outer wall of the main shaft (3a), and the inner top wall and outer bottom wall of the upper rolling bearing (11) press against the limiting seat (3b) and the annular surface (1b) respectively.

3. The bearing hydrostatic rotary table according to claim 2, characterized in that, A retaining ring (12) is horizontally provided between the positioning ring (1a) and the worktable (2). The retaining ring (12) is sleeved outside the spindle (3a). The retaining ring (12) is fixed on the top wall of the positioning ring (1a). A protruding ring (12a) is formed on the bottom wall of the retaining ring (12), and the protruding ring (12a) presses against the top wall of the outer ring.

4. The bearing hydrostatic rotary table according to claim 3, characterized in that, The upper end of the retaining ring (12) forms a seal with the worktable (2) through the oil seal (13), and the lower end of the retaining ring (12) forms a seal with the positioning ring (1a).

5. The bearing hydrostatic rotary table according to claim 4, characterized in that, The lower end of the retaining ring (12) forms a seal with the positioning ring (1a) through the sealing ring (14).

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