CN210756420U

CN210756420U - Locking rotary table

Info

Publication number: CN210756420U
Application number: CN201921225686.9U
Authority: CN
Inventors: 林绿高
Original assignee: Zhejiang Chr Intelligent Equipment Co ltd
Current assignee: Zhejiang Chr Intelligent Equipment Co ltd
Priority date: 2019-07-31
Filing date: 2019-07-31
Publication date: 2020-06-16
Anticipated expiration: 2029-07-31

Abstract

The utility model relates to a locking revolving stage, include: the base is provided with a rotary table which can rotate relative to the base; the central shaft is assembled in the base and is vertically arranged relative to the rotary table, and the first end of the central shaft is connected with the rotary table and drives the rotary table to rotate; the worm wheel and worm pair transmission mechanism comprises a worm wheel and at least one worm, wherein the worm wheel is connected to the central shaft and can drive the central shaft to rotate, the worm is in driving connection with the worm wheel, and the corresponding worm is rotatably connected to the base; the first driving device is in driving connection with the corresponding worm and drives the worm to rotate; the worm is provided with a pair of first and second worms respectively, the first and second worms are arranged in parallel and are respectively and correspondingly positioned on two sides of the worm wheel, and the first and second worms are in driving connection with the worm wheel; the first driving device is in driving connection with the two worms and drives the two worms to synchronously rotate. The locking rotary table can effectively eliminate the back clearance between the worm and the gear to perform accurate indexing.

Description

Locking rotary table

Technical Field

The utility model relates to a machine tool machining technical field especially relates to a locking revolving stage.

Background

At present, the numerical control indexing rotary table used by various machine tools mainly plays a role in indexing in the angle direction. In the linkage working state, the rotating part does not need to be locked and fixed. However, after indexing, especially during milling or broaching, locking is required because the clearance of the transmission mechanism is large, or the driving motor of the transmission mechanism is not enough to overcome the counter force of milling, and the workpiece is easily scrapped when the workpiece is machined without locking. If broaching machining is carried out on the mortises of the turbine disc, the requirements on the indexing rotary table are as follows: not only needs to be accurately indexed, but also needs to be capable of bearing large-tonnage broaching force on the periphery of the rotary table.

In order to solve the technical problem, the application numbers are as follows: CN201220474787.1 (No. CN202877898U) discloses a multifunctional precision workbench for machining center, which is provided with a brake ring and is controlled by oil pressure, when braking is required, the brake ring is expanded and tightly fitted with an index plate on the whole circumferential surface by pressurizing hydraulic oil in the brake ring, so as to lock the index plate, and the workbench has strong locking force and can bear heavy cutting, thereby realizing precise rotary indexing.

However, the above patent has certain disadvantages that firstly, the rotary indexing process of the indexing disc of the table is transmitted by the worm and gear pair, but in actual use, the indexing precision of the turntable is reduced due to the inevitable transmission gap between the worm and gear, and the indexing requirement of a precise workpiece is difficult to meet; in addition, when a workpiece fixed on the turntable is subjected to cutting, particularly broaching, the turntable itself generates large vibration, and when the workpiece acts on the worm wheel or the worm, a gap between the worm wheel and the worm is increased, so that back clearance adjustment needs to be performed for many times, and the machining efficiency is low. How to provide a locking turntable capable of effectively eliminating backlash and performing accurate indexing becomes a technical problem to be solved urgently by the technical personnel in the technical field.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that to prior art's current situation, provide a can effectively eliminate the back clearance between the worm gear and the worm and carry out the locking revolving stage of accurate graduation.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: a locking turret comprising:

the base is provided with a rotary table which can rotate relative to the base;

the central shaft is assembled in the base and is vertically arranged relative to the rotary table, and the first end of the central shaft is connected with the rotary table and drives the rotary table to rotate;

the worm wheel and worm pair transmission mechanism comprises a worm wheel and at least one worm, wherein the worm wheel is connected to the central shaft and can drive the central shaft to rotate, the worm is in driving connection with the worm wheel, and the corresponding worm is in rotating connection with the base;

the first driving device is in driving connection with the corresponding worm and drives the worm to rotate;

the worm is provided with a pair of first and second worms respectively, the first and second worms are arranged in parallel and are respectively and correspondingly positioned on two sides of the worm wheel, and the first and second worms are in driving connection with the worm wheel;

the first driving device is in driving connection with the two worms and drives the two worms to synchronously rotate.

In order to drive the two worm wheels positioned on the two sides of the worm wheel to synchronously rotate, the first driving device comprises a servo motor and a reduction gearbox connected with an output shaft of the servo motor, and an output end of the reduction gearbox is in driving connection with the two worms through a gear transmission assembly;

the gear transmission assembly includes:

the driving gear is connected with an output shaft of the reduction box;

the first driven gear is connected to the first worm and is directly meshed with the driving gear;

the second driven gear is connected to the second worm and is spaced from the first driven gear by a certain distance;

and the transition gear is arranged between the driving gear and the second driven gear and is simultaneously meshed with the driving gear and the second driven gear.

In order to conveniently assemble the two worm gears on the base, a first through groove and a second through groove which are communicated from front to back are formed in the base, and a front bearing assembly and a rear bearing assembly are arranged in the first through groove and the second through groove;

the first worm is correspondingly arranged in the first through groove, and the front end and the rear end of the first worm are respectively matched on the front bearing assembly and the rear bearing assembly in the first through groove in a rotating manner;

the second worm is correspondingly arranged in the second through groove, and the front end and the rear end of the second worm are respectively in running fit with the front bearing assembly and the rear bearing assembly in the second through groove.

As an improvement, the central shaft is provided with a step excircle with a narrow lower part and a wide upper part, and the worm wheel can be sleeved on the step excircle from bottom to top and is fixed with the central shaft through a screw. The structure arrangement greatly facilitates the assembly of the worm wheel and ensures the stability of the worm wheel and worm transmission.

In order to enable the central shaft to flexibly rotate relative to the base, a cylindrical sinking groove is formed in the top surface of the base, the central shaft is vertically placed in the sinking groove, a rotary table bearing is further arranged between the central shaft and the inner peripheral wall of the sinking groove of the base, and the rotary table bearing is connected to the upper section of the central shaft in a sleeved mode and is used for bearing the bottom of the rotary table. The adopted rotary table bearing has high axial and radial bearing capacity, and the stable rotation of the rotary table is ensured.

In order to control the rotary table to perform indexing more accurately, the lower end of the central shaft is also provided with an angle encoder.

In order to radially lock the rotary table, the hydraulic expansion assembly is arranged between the base and the rotary table and comprises an expansion sleeve which can be stretched and deformed in the radial direction, the expansion sleeve is connected to the base and upwards and outwards exposes out of the upper surface of the base, a first annular groove is correspondingly arranged on the bottom surface of the rotary table, and the exposed part of the expansion sleeve, which exposes out of the upper surface of the base, is accommodated in the first annular groove. The hydraulic expansion assembly is convenient to assemble and disassemble, and can radially hold the rotary table tightly.

In order to convey external hydraulic oil into the expansion sleeve, a hydraulic flow passage for inputting the external hydraulic oil into the expansion sleeve is arranged on the base, and the hydraulic flow passage penetrates from the outer wall surface of the base to the arrangement position of the expansion sleeve above the base; and an oil pipe joint for connecting with an external oil pipe is arranged at the liquid inlet of the hydraulic flow channel.

In order to axially lock the rotary table and further improve the firmness of the rotary table during locking so as to ensure that the periphery of the rotary table can bear larger broaching force, the rotary table axial locking mechanism also comprises an axial locking mechanism arranged on the base, and the axial locking mechanism comprises a plurality of groups of oil cylinder pull rod assemblies capable of axially locking the rotary table; each group of oil cylinder pull rod assemblies respectively comprise an oil cylinder, a pull rod connected with the output end of the oil cylinder and a pressing block arranged at the end part of the pull rod, the oil cylinder is fixed on the base and drives the pull rod to reciprocate vertically, and the pressing block can move downwards and is pressed on the rotary table.

In order to ensure that the stress of the rotary table is more uniform when the rotary table is locked in the axial direction, four groups of oil cylinder pull rod assemblies are respectively and uniformly arranged on the outer side of the rotary table; and a second annular groove for the pressing block to extend inwards is formed in the peripheral wall of the rotary table. The second annular groove provides corresponding pressing points for pressing blocks of all groups of oil cylinder pull rod assemblies, and the rotation of the rotary table is facilitated, namely when the rotary table needs to be rotationally indexed, the pressing blocks only need to move upwards in the vertical direction and are separated from the lower wall surface of the second annular groove.

Compared with the prior art, the utility model has the advantages that: the locking turntable of the utility model is provided with a worm-gear and worm-gear pair transmission mechanism, which comprises two worms respectively arranged at two sides of a worm wheel, and the two worms can synchronously act on the worm wheel under the driving of the first driving device, thereby having good anti-backlash effect and leading the turntable to have higher repeated positioning precision; on the other hand, the two worms are synchronously driven on the two sides of the worm wheel, so that the stress of the worm wheel is more uniform, a larger gap between the worm and the worm wheel is avoided when the rotary table vibrates due to the bearing of larger broaching force, and the stability of the rotary table in the using process is improved.

Drawings

Fig. 1 is a schematic view of a top view angle structure of a locking turntable according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a front view angle of the locking turntable according to the embodiment of the present invention;

FIG. 3 is a cross-sectional view taken at A-A of FIG. 1;

fig. 4 is a sectional view taken at B-B in fig. 3.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

Referring to fig. 1 to 4, the locking turntable includes a base 10, a central shaft 20, a turntable 60, a turntable bearing 17, a worm and worm gear pair transmission mechanism, a gear transmission assembly, a servo motor 41, and an angle encoder 22, where the base 10 is a square base, a sunken groove 14 opened downward is formed in a middle position of a top of the base 10, the central shaft 20 is vertically disposed in the sunken groove 14, the turntable 60 is disposed above the base 10 and is coaxial with the central shaft 20, specifically, the turntable bearing 17 is disposed between the central shaft 20 and an inner peripheral wall of the sunken groove 14 of the base 10, and an upper portion of the turntable bearing 17 is supported on a bottom surface of the turntable 60, so that the turntable 60 is driven by the central shaft 20 to stably rotate relative to the base 10. The upper plane of the turntable 60 is a working surface to which a workpiece to be machined (e.g., a turbine disk) is connected through a corresponding workpiece holder, and the base 10 itself has a mounting surface to which other equipment can be connected.

Referring to fig. 4, the worm-and-wheel pair transmission mechanism includes a worm wheel 31 and two worms, which are a first worm 321 and a second worm 322, respectively. The worm wheel 31 is sleeved on the middle part of the central shaft 20 and fixed by a screw, specifically, the middle part of the central shaft 20 is provided with a step excircle 21 with a narrow lower part and a wide upper part, and the worm wheel 31 is sleeved on the step excircle 21 from bottom to top. The two worms are symmetrically arranged on two sides of the worm wheel 31 and are arranged in parallel, and more specifically, the base 10 is provided with two through grooves which are through from front to back, the two worms are correspondingly arranged in the two through grooves, the two through grooves are respectively positioned on the left side and the right side of the sunk groove and are communicated with the sunk groove 14 in the middle area, so that the worms and the worm wheel 31 are in transmission fit at the communicated position. In order to detect the rotation angle of the turntable 60 so as to control the turntable 60 to be indexed more precisely, the lower end portion of the central shaft 20 is sleeved with an angle encoder 22.

Referring to fig. 3 and 4, the two through slots are respectively a first through slot 11 and a second through slot 12, a front bearing assembly 131 and a rear bearing assembly 132 are respectively disposed at front and rear two slot openings of the first through slot 11 and the second through slot 12, specifically, the first worm 321 is correspondingly disposed in the first through slot 11, and front and rear ends of the first worm are respectively rotationally fitted on the front bearing assembly 131 and the rear bearing assembly 132 in the first through slot 11, and the second worm 322 is correspondingly disposed in the second through slot 12, and front and rear ends of the second worm are respectively rotationally fitted on the front bearing assembly 131 and the rear bearing assembly 132 in the second through slot 12. The front bearing assembly 131 and the rear bearing assembly 132 each include a bearing piece and a corresponding interference fit structure for fixing the bearing piece on the base 10, which is prior art and will not be described in detail.

Referring to fig. 4, a servo motor 41 is disposed at a front position of the base 10, and an output shaft thereof drives two worm screws (a first worm screw 321 and a second worm screw 322) to rotate synchronously through a gear transmission assembly. Since the two worms are respectively arranged at two sides of the worm wheel 31, in order to make the two worms drive the worm wheel 31 to rotate in the same rotating direction, the rotating directions of the two worms are opposite, and in order to achieve the purpose, the gear transmission assembly comprises a driving gear 51, a transition gear 54, and a first driven gear 52 and a second driven gear 52, wherein, an output shaft of the servo motor 41 is connected with the driving gear 51 through a reduction box 42 and drives the driving gear 51 to rotate, the two driven gears are respectively arranged at the front end positions of the two worms, specifically, the first driven gear 52 is connected with the first worm 321 and directly meshed with the driving gear 51, the second driven gear 52 is connected with the second worm 322 and is spaced from the first driven gear 52, the transition gear 54 is arranged between the driving gear 51 and the second driven gear 52 and is simultaneously meshed with the driving gear 51 and the second driven gear 52, specifically, the transition gear 54 is fixed to the base 10 by a gear shaft.

Referring to fig. 2 and 3, the locking turret in this embodiment further has a dual locking function, and specifically includes a hydraulic expansion assembly that performs expansion locking on the turret 60 in a radial direction, and an axial locking mechanism that performs press locking on the turret 60 in an axial direction of the turret 60, where the hydraulic expansion assembly is disposed between a bottom surface of the turret 60 and a top surface of the base 10, performs expansion locking in the radial direction of the turret 60, and the axial locking mechanism is fixed on the base 10 and located outside the turret 60, and performs axial locking on the turret 60 by pressing down.

Referring to fig. 3, the hydraulic expansion assembly includes an expansion sleeve 70 capable of extending and retracting in a radial direction, specifically, the expansion sleeve 70 is fixed on the base 10 by screws and exposed out of the upper surface of the base 10, and is disposed coaxially with the central shaft 20, the base 10 is provided with a plurality of hydraulic flow passages 15 for external hydraulic oil to enter the expansion sleeve 70, specifically, in this embodiment, the hydraulic flow passages 15 are provided with a plurality of (only two are shown in fig. 3) and are respectively and uniformly spaced along the base 10, the hydraulic flow passages 15 penetrate from the outer wall surface of the base 10 to the expansion sleeve 70 placement position above the base 10, and are provided with a liquid inlet and a liquid outlet, the liquid inlet is provided with an oil pipe joint 16 for connecting with an external oil pipe, and the liquid outlet is communicated with an inlet of the expansion sleeve 70. The bottom of the turntable 60 is correspondingly provided with a first annular groove 61 for accommodating the expansion sleeve 70, and the opening of the first annular groove 61 faces the expansion sleeve 70 downwards, so that when the turntable 60 is assembled on the base 10, the expansion sleeve 70 can just extend into the first annular groove 61. When hydraulic oil is introduced into the expansion sleeve 70, the expansion sleeve 70 can expand and deform in the radial direction and press the inner side wall and the outer side wall of the first annular groove 61 of the turntable 60, so that the turntable 60 is locked; after hydraulic oil is not introduced, the expansion sleeve 70 contracts, and a corresponding gap is reserved between the expansion sleeve and the inner and outer side walls of the first annular groove 61, so that the rotary table 60 can rotate freely.

The axial locking mechanism comprises a plurality of groups of oil cylinder pull rod assemblies 80 connected to the base 10, each oil cylinder pull rod assembly 80 is uniformly arranged along the periphery of the rotary table 60 and specifically comprises an oil cylinder 81, a pull rod 82 and a pressing block 83 arranged at the end part of the pull rod 82, the output end of the oil cylinder 81 is connected with the pull rod 82, and the pull rod 82 is driven to drive the pressing block 83 to reciprocate up and down. The outer peripheral wall of the turntable 60 is correspondingly provided with a second annular groove 62 recessed inwards, and the opening of the second annular groove 62 faces outwards, so that the pressing block 83 on the pull rod 82 extends into the second annular groove 62 to press the turntable 60 downwards.

The locking turntable in the embodiment has a worm-and-gear pair transmission mechanism, which comprises two worms respectively arranged on two sides of the worm wheel 31, and the two worms can synchronously act on the worm wheel 31 under the driving of the first driving device, so that the locking turntable has a good anti-backlash effect, and the turntable 60 has high repeated positioning precision; and, two worms carry out synchronous drive in worm wheel 31 both sides, this makes worm wheel 31's atress more even, when having avoided revolving stage 60 to bear great broaching force and vibrate, produce great clearance between worm and the worm wheel 31, improved the stability of revolving stage 60 in the use. In addition, the locking state has a double locking function, on one hand, the turntable 60 is tightly held by the hydraulic expansion assembly fixed on the base 10 to realize the locking of the turntable 60 in the radial direction, and on the other hand, the turntable 60 is locked in the axial direction by applying a vertical pulling force to the turntable 60 by the oil cylinder pull rod assembly 80. The locking rotary table with the double locking function can bear heavy cutting force of 20 tons on the periphery, and is particularly suitable for broaching heavy workpieces (such as turbine discs).

In order to more conveniently understand the technical solution of the present embodiment, in the present embodiment, the position of the turntable 60 is "up", and correspondingly, the position of the base 10 is "down"; the "front-back direction" is the same as the direction of the axis of the worm, wherein the position of the servo motor 41 is "front", and correspondingly, the position deviating from the servo motor 41 is "back"; the first worm 321 is located at the position "right", and correspondingly, the second worm 322 is located at the position "left".

Claims

1. A locking turret comprising:

a base (10) on which a turntable (60) capable of rotating relative to the base (10) is provided;

the central shaft (20) is assembled in the base (10) and is vertically arranged relative to the base (10), and the first end of the central shaft (20) is connected with the rotary table (60) and drives the rotary table (60) to rotate;

the worm-gear pair transmission mechanism comprises a worm wheel (31) which is connected to the central shaft (20) and can drive the central shaft (20) to rotate and at least one worm which is in driving connection with the worm wheel (31), and the corresponding worm is rotationally connected to the base (10);

the method is characterized in that: the pair of worms is respectively a first worm (321) and a second worm (322), the first worm (321) and the second worm (322) are arranged in parallel and are respectively and correspondingly positioned on two sides of the worm wheel (31), and the first worm (321) and the second worm (322) are in driving connection with the worm wheel (31);

2. The locking turret of claim 1, wherein: the first driving device comprises a servo motor (41) and a reduction gearbox (42) connected with an output shaft of the servo motor (41), and an output end of the reduction gearbox (42) is in driving connection with the two worms through a gear transmission assembly;

the gear transmission assembly includes:

a drive gear (51) connected to an output shaft of the reduction gearbox (42);

a first driven gear (52) connected to the first worm (321) and directly engaged with the driving gear (51);

a second driven gear (523) connected to the second worm (322) and spaced apart from the first driven gear (52);

and a transition gear (54) which is arranged between the driving gear (51) and the second driven gear (523) and is meshed with the driving gear (51) and the second driven gear (523) simultaneously.

3. The locking turret according to claim 2, wherein: a first through groove (11) and a second through groove (12) which are communicated from front to back are formed in the base (10), and a front bearing assembly (131) and a rear bearing assembly (132) are arranged in each of the first through groove (11) and the second through groove (12);

the first worm (321) is correspondingly arranged in the first through groove (11), and the front end and the rear end of the first worm are respectively and rotatably matched on a front bearing assembly (131) and a rear bearing assembly (132) in the first through groove (11);

the second worm (322) is correspondingly arranged in the second through groove (12), and the front end and the rear end of the second worm are respectively in running fit with the front bearing assembly (131) and the rear bearing assembly (132) in the second through groove (12).

4. The locking turret of claim 1, wherein: the central shaft (20) is provided with a step excircle (21) with a narrow lower part and a wide upper part, and the worm wheel (31) can be sleeved on the step excircle (21) from bottom to top and is fixed with the central shaft (20) through a screw.

5. The locking turret of claim 1, wherein:

be equipped with cylindrical heavy groove (14) on the top surface of base (10), center pin (20) are vertical places in this heavy groove (14), center pin (20) with still be equipped with revolving stage bearing (17) between heavy groove (14) internal perisporium of base (10), this revolving stage bearing (17) cover is established and is connected the upper segment position of center pin (20), the top butt of revolving stage bearing (17) is in the bottom of revolving stage (60).

6. The locking turret of claim 1, wherein: the central shaft (20) is further provided with an angle encoder (22) at a second end remote from the turntable.

7. Locking turret according to any of claims 1-6, wherein: still including locating base (10) with hydraulic pressure tight subassembly that expands between revolving stage (60), this hydraulic pressure tight subassembly that expands is including can radially carrying out the tight cover (70) that expands of flexible deformation, should expand tight cover (70) and connect on base (10) and upwards expose the upper surface of this base (10), correspond on the bottom surface of revolving stage (60) and be equipped with first annular groove (61), the partial holding that exposes of the upper surface that expands tight cover (70) and expose base (10) is in this first annular groove (61).

8. The locking turret of claim 7, wherein: a hydraulic flow passage (15) for inputting external hydraulic oil into the expansion sleeve (70) is arranged on the base (10), and the hydraulic flow passage (15) penetrates from the outer wall surface of the base (10) to the arrangement position of the expansion sleeve (70) above the base (10);

and an oil pipe joint (16) used for being connected with an external oil pipe is arranged at the liquid inlet position of the hydraulic flow passage (15).

9. The locking turret of claim 7, wherein: the axial locking mechanism is arranged on the base (10) and comprises a plurality of groups of oil cylinder pull rod assemblies (80) capable of axially locking the rotary table (60);

each group of oil cylinder pull rod assemblies (80) comprises an oil cylinder (81), a pull rod (82) connected with the output end of the oil cylinder (81) and a pressing block (83) arranged at the end part of the pull rod (82), wherein the oil cylinder (81) is fixed on the base (10) and drives the pull rod (82) to reciprocate vertically, and the pressing block (83) can move downwards and is pressed on the rotary table (60).

10. The locking turret of claim 9, wherein: four groups of oil cylinder pull rod assemblies (80) are uniformly arranged on the outer side of the rotary table (60) respectively;

and a second annular groove (62) which can allow the pressing block (83) to extend inwards is formed in the outer peripheral wall of the rotary table (60).