CN216882986U - Indexing mechanism and machine tool special for machining cambered surface cam - Google Patents

Indexing mechanism and machine tool special for machining cambered surface cam Download PDF

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Publication number
CN216882986U
CN216882986U CN202123364488.0U CN202123364488U CN216882986U CN 216882986 U CN216882986 U CN 216882986U CN 202123364488 U CN202123364488 U CN 202123364488U CN 216882986 U CN216882986 U CN 216882986U
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worm
moving table
indexing mechanism
indexing
workpiece
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CN202123364488.0U
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李体仁
张萌
杨立军
梁金生
刘言松
李海涛
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Shaanxi University of Science and Technology
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Shaanxi University of Science and Technology
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Abstract

The utility model provides an indexing mechanism and a machine tool special for processing a cambered surface cam, wherein the indexing mechanism is a worm and gear indexing mechanism, a worm wheel disc is fixed on a base and is still, a worm and the outer edge of a worm wheel are meshed with each other, the input end of the worm is used for indexing motion output, a positioning central shaft is arranged on the central axis of the worm wheel, an auxiliary fan-shaped guide rail is additionally arranged on the worm wheel, and a main shaft is enabled to surround the fan-shaped guide rail by taking the positioning central shaft as a fixed point to realize high-precision indexing. The utility model directly pushes the main shaft to realize indexing swing by the torque generated by the rotation of the worm, and has the advantages of compact equipment structure, small volume, stable output, no creeping and torsional vibration phenomena and capability of realizing the minimum center distance between the machine tool main shaft rotating coordinate and the workpiece rotating coordinate. The machine tool equipment has the remarkable effects of compact structure, high machining precision, large machining range and high rigidity of the main shaft.

Description

Indexing mechanism and machine tool special for machining cambered surface cam
Technical Field
The utility model belongs to the technical field of machine tools, and particularly relates to a special indexing mechanism for machining a cambered surface cam and a cambered surface cam machining tool.
Background
The cambered indexing cam mechanism is a high-precision indexing mechanism and is widely used for realizing efficient and accurate intermittent indexing motion and stepping motion on various automatic machines and automatic production lines. The indexing mechanism has higher requirements on the machining precision and the geometric precision of the cambered surface indexing cam. However, in the worm and gear indexing device used for the traditional arc cam machining machine tool, a worm gear cannot drive a worm to reversely transmit, and cannot be applied to mechanical equipment with large required output torque and high motion precision, so that the machined arc cam has low precision, short service life and is only applicable to low-speed occasions, and the indexing requirements of fast beat and high precision of production cannot be met.
The research and development of the arc cam processing equipment in China is unsatisfactory mainly because on one hand, the advanced arc cam processing equipment is monopolized abroad and the numerical control system of the equipment is forbidden to be opened domestically; on the other hand, the existing machine tool in China has insufficient layout rigidity, small dynamic processing range, low processing precision and larger error of processing the cam, so that the processing capability of the high-precision cambered surface cam in China can not meet the requirement of the domestic market far.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, the present invention provides an indexing mechanism dedicated to machining a cam with a curved surface, which solves the above-mentioned problems in the prior art.
In order to achieve the above objects and other related objects, the present invention provides the following technical solutions:
the utility model provides a dedicated indexing mechanism of processing cambered surface cam, is including the worm wheel of fixing at the lathe base, and the worm wheel central axis direction is provided with the location center pin, and the outer edge of worm wheel top surface is provided with the fan-shaped guide rail that is used for placing the headstock, and the worm wheel side is provided with the worm wheel seat, and the worm setting is in the worm wheel seat and with worm wheel outer fringe intermeshing, and the worm is rotated through the worm servo motor drive worm that sets up in the worm wheel seat outside.
The worm servo motor adopts a 5120-wire encoder.
A machine tool using a special indexing mechanism for processing a cambered surface cam is based on the special indexing mechanism for processing the cambered surface cam;
the machine tool comprises a machine tool body, a base, a three-axis sliding table and a rotary workbench, wherein the three-axis sliding table is arranged above the machine tool body, the base and the rotary workbench are arranged on one side of the machine tool body, and the rotary workbench is arranged above the base;
the three-axis sliding table consists of a first moving table, a second moving table, a third moving table, a workpiece rotary indexing shaft and a tip tailstock, wherein the third moving table is arranged above the machine body, the first moving table is arranged above the third moving table, the first moving table and the third moving table form a cross sliding table, the second moving table is arranged above the first moving table, and the side wall of the second moving table is also provided with the workpiece rotary indexing shaft and the tip tailstock; the first mobile station is used for adjusting the horizontal position of a workpiece to be processed; the second moving table is used for adjusting the height of the workpiece to be machined and clamping and rotary feeding the workpiece to be machined; the third moving table is used for adjusting the auxiliary feeding W direction feeding of the workpiece.
The rotary worktable comprises a tool electric spindle, a dividing mechanism special for machining the cambered surface cam, a fourth movable table and a servo motor, wherein the fourth movable table is arranged above the dividing mechanism, one end of the fourth movable table is connected with the positioning central shaft, the other end of the fourth movable table is fixedly connected with a worm seat, the tool electric spindle is arranged on the fourth movable table, a tool is arranged on the tool electric spindle and rotates around the axis of the spindle, and the fourth movable table is driven by the servo motor to control the tool to realize the functions of circular feeding and tool feeding and retracting in the machining process and is jointly used for adjusting the front and back positions between the machining tool and a workpiece to be machined together with the third movable table.
And a z-axis lead screw is arranged on the fourth moving platform, a main shaft mounting seat is arranged on the z-axis lead screw, and the tool electric main shaft is arranged on the main shaft mounting seat.
The first mobile station, the second mobile station, the third mobile station and the fourth mobile station are respectively arranged on corresponding adaptive sliding rails.
The three-jaw chuck and the tip tailstock are positioned on the same horizontal central axis.
And a rocking handle is arranged on one side of the third mobile station.
Compared with the prior art, the utility model has the following advantages:
the utility model adopts the innovative worm and gear indexing mechanism, solves the output problem of large torque of the rotary coordinate of the machine tool main shaft, and effectively solves the problem of space interference between two vertically staggered shafts, so that the machine tool equipment has compact structure and stable output motion without creeping and torsional vibration.
The novel worm and gear indexing mechanism adopted by the utility model has the characteristics of convenient gap adjustment, no influence of abrasion on machining precision and capability of comprehensively ensuring high-precision positioning of the rotary table.
According to the utility model, the spindle box swings on the fan-shaped guide rail around the positioning central shaft, the loss of each transmission part is reduced by applying a lever principle, the rigidity of the spindle is increased, so that the precise indexing of the spindle is realized, and the machining precision of the cambered surface indexing cam is greatly improved.
The utility model adopts the positioning central shaft to increase the rigidity of the main shaft. A positioning central shaft is arranged on the central axis of the worm gear, and a fan-shaped guide rail is additionally arranged above the worm gear to serve as an auxiliary support of the spindle box. The main shaft swings on the fan-shaped track by taking the positioning central shaft as a fixed point, so that the rigidity of the main shaft is increased, the loss of each transmission part is reduced, and the machining precision of the cambered surface indexing cam is improved.
The horizontal machining center adopted by the utility model can realize the machining of the internal-meshing arc-surface cam with the center distance smaller than 25mm by adjusting the feeding machining positions of the three-axis sliding table and the fourth moving table, simultaneously reduces the bearing load of the worm and gear indexing mechanism, reduces the abrasion and the shaking of the machine tool in the machining process, improves the rigidity of the machine tool, occupies small area, saves the investment cost in the actual production and improves the economic efficiency.
Drawings
The utility model is described in further detail below with reference to specific embodiments and with reference to the following drawings.
Fig. 1 is a schematic structural diagram of a worm and gear indexing mechanism provided by the utility model.
Fig. 2 is a schematic view of the position of the positioning central axis provided by the present invention.
Fig. 3 is a schematic view of a first perspective structure of a machine tool using the mechanism of the present invention.
Fig. 4 is a schematic structural diagram of a second perspective view of a machine tool using the mechanism of the utility model.
Wherein the reference numerals are specified as follows: the automatic numerical control lathe comprises a lathe bed (1), a third moving table (2), a rocking handle (3), a first moving table (4), a Y-axis servo motor (5), a second moving table (6), a workpiece rotary indexing shaft (7), a tip tailstock (8), a base (9), a worm and gear indexing mechanism (10), a sector sliding rail (11), a fourth moving table (12), a Z-axis sliding block (13), a main shaft mounting seat (14), a cutter electric main shaft (15), a positioning central shaft (16), a worm (17), a Z-axis servo motor (18), a worm servo motor (19), a worm seat (20), an X-axis servo motor (21), an X-axis screw rod (22), a Y-axis lifting screw rod (23), a three-jaw chuck (24), a Z-axis screw rod (25) and a Y-axis sliding rail (26).
Detailed Description
As shown in figures 1 and 2, the utility model discloses a special indexing mechanism for processing a cambered surface cam, which comprises a worm wheel fixed on a machine tool base 9, wherein a positioning central shaft 16 is arranged in the central axis direction of the worm wheel, a fan-shaped guide rail 11 for placing a spindle box is arranged on the outer edge of the top surface of the worm wheel, a worm wheel seat 20 is arranged on the side surface of the worm wheel, a worm 17 is arranged in the worm wheel seat 20 and is meshed with the outer edge of the worm wheel, the worm 17 is driven to rotate by a worm servo motor 19 arranged on the outer side of the worm wheel seat 20, and a servo motor 18 arranged on the inner side of the worm wheel seat 20 is connected with a fourth moving table 12.
The innovative indexing mechanism 10 of the indexing mechanism overturns the traditional worm gear transmission mode, a worm wheel disc is fixed on a base 9 and is stationary, a worm 17 is driven to rotate through a worm servo motor 19, and torque generated by rotation of the worm 17 directly pushes a spindle mounting seat 14 on a fourth mobile station 12 to realize rotary swing through a worm seat 20 so as to realize swing of a spindle in the B direction.
The worm wheel shaft in the indexing mechanism does not bear torque, so that the diameter of the worm wheel shaft can be greatly reduced on the premise that the mechanism realizes larger output torque, the problem of space interference of two vertically staggered shafts in a transmission device is solved, the equipment is compact in structure, small in size and light in weight, and the indexing mechanism has the characteristics of stable output and no creeping and torsional vibration.
The worm servo motor 19 adopts a 5120-wire encoder, the subdivision minimum precision of one rotation of the servo motor is 360 degrees/5120 =0.07 degrees, and the precision of the dividing device can reach 0.07 degrees/50 =0.0014 degrees by adopting a worm and gear dividing mechanism with the reduction ratio of 1/50. The high indexing and positioning accuracy can be achieved, and the compensation and adjustment of the meshing clearance can be realized by adjusting the axial position of the worm 17, so that the machining accuracy is not influenced by abrasion, and the high-accuracy positioning characteristic of the rotary table is comprehensively ensured.
Referring to fig. 3 and 4, a machine tool adopting the indexing mechanism is disclosed, and the machine tool comprises a machine tool body 1, a base 9, a three-axis sliding table and a rotary worktable, wherein the three-axis sliding table is arranged above the machine tool body 1, the base 9 is arranged on one side of the machine tool body 1, and the rotary worktable is arranged above the base 9;
the three-axis sliding table is composed of a first moving table 4, a second moving table 6, a third moving table 2, a workpiece rotary indexing shaft 7 and a top tailstock 8, wherein the third moving table 2 is arranged above the machine body 1, the first moving table 4 is arranged above the third moving table 2, the first moving table and the third moving table form a cross sliding table, the second moving table 6 is arranged on the first moving table 4, the side wall of the second moving table 6 is further provided with the workpiece rotary indexing shaft 7 and the top tailstock 8, a three-jaw chuck 24 is arranged on the workpiece rotary indexing shaft 7, and the top tailstock 8 is matched to clamp a workpiece to be machined and meanwhile the workpiece rotary indexing shaft 7 drives the workpiece to swing an A shaft. The first moving table 4 is used for adjusting the x-direction feeding of the workpiece to be processed; the second moving table 6 is used for adjusting Y-direction feeding of the workpiece to be processed and realizing clamping and rotary feeding of the workpiece to be processed; the third mobile station 2 controls a workpiece to be processed to assist W direction feeding, an X-axis servo motor 20 is arranged on the lower side of the first mobile station 4, a Y-axis servo motor 5 is arranged on one side of the second mobile station 6, and a rocking handle 3 is arranged on one side of the third mobile station 2.
The rotary worktable comprises a tool electric spindle 15, the special indexing mechanism 10 for machining the arc cam, namely a worm and gear indexing mechanism 10, a fourth moving table 12 and a servo motor, wherein the fourth moving table 12 is arranged above the indexing mechanism 10, one end of the fourth moving table is connected with a positioning central shaft 16, the other end of the fourth moving table is fixedly connected with a worm seat 20, the tool electric spindle 15 is arranged on the fourth moving table 12, a tool is arranged on the tool electric spindle 15 and rotates around the axis of the spindle, and the fourth moving table 12 is driven by the servo motor 18 to control the tool to realize the functions of circular feeding and tool advancing and retreating in the machining process and is used for adjusting the front and back positions between the machining tool and a workpiece to be machined together with the third moving table 2.
Two Z-axis guide rails are arranged on the fourth mobile station 12, a main shaft mounting seat 14 is fixedly mounted on four sliding blocks 13 of the Z-axis guide rails, and a Z-axis lead screw 25 is fixed on the main shaft mounting seat 14; when the servo motor 18 is started, the z-axis lead screw 25 drives the spindle mounting base 14 to realize the functions of circular feeding and tool feeding and retracting in the machining process and is used together with the third moving table 2 for adjusting the front and rear positions between the machining tool and the workpiece to be machined. An electric spindle 15 is arranged on the fourth mobile station 12, and a cutter is arranged at the output end of the electric spindle 15 and can rotate around the axis of the spindle.
In the worm and gear indexing mechanism 10, a worm wheel is fixed on a base 9 through a fixing screw and is stationary, a positioning central shaft 16 is arranged in the direction of the central axis of the worm wheel, an auxiliary fan-shaped guide rail 11 is additionally arranged on the worm wheel to increase the rigidity of a machine tool, a worm seat 20 is fixed on the lower side of a fourth mobile station 12, a worm 17 is arranged in the worm seat 20, the outer edges of the worm wheel are meshed with each other, the worm 17 is driven to rotate by controlling a servo motor 19, and the worm rotates to enable generated torque to directly push the fourth mobile station 12 to swing at high precision on the fan-shaped rail 11 by taking the positioning central shaft 16 as a fixed point through the worm seat 20. The axial position of the worm 17 is adjusted to eliminate backlash.
In this embodiment, the three-jaw chuck 21 and the tip tailstock 8 are located on the same horizontal central axis.
Through the technical scheme, after the three-jaw chuck 21 clamps the workpiece, the workpiece is kept stable on the horizontal central axis through the abutting action of the positioning seat 8 at the tail part.
In this embodiment, the machining tool is one of a milling cutter and a sharpening cutter, and a suitable tool can be selected according to a machining process required by a workpiece to be machined.
In this embodiment, the first mobile station 4, the second mobile station 6, the third mobile station 2, and the fourth mobile station 12 are all mounted on corresponding adaptive slide rails.
When the utility model is used, the control is carried out by matching with a numerical control machine tool control system in the prior art, and the utility model can be realized by The following functions:
feeding in the X direction: the servo motor 20 drives the X-axis screw rod 21 to rotate, so that the workpiece runs along the X-axis guide rail;
feeding in the Y direction: the servo motor 5 drives the lifting screw rod 23 to rotate, so that the workpiece runs along the Y-axis guide rail;
auxiliary W-direction feeding: the whole workpiece can be controlled to run along the W-axis guide rail by rotating the rocking handle 3;
feeding in the Z direction: the servo motor 18 drives the Z-axis screw rod 25 to rotate, and the Z-axis screw rod is connected with the spindle box mounting seat 14, so that the spindle runs along the Z-axis guide rail;
when the A shaft runs: the workpiece rotating indexing shaft 7 drives the workpiece to rotate;
when the B axis runs: the servo motor 19 drives the worm 17 to rotate, and the worm drives the spindle box to swing around the positioning central shaft 16 on the fan-shaped track 11 to realize high-precision indexing of the machine tool.
The using method of the utility model is as follows:
firstly, a workpiece is arranged on a workpiece rotary indexing shaft by using a three-jaw chuck 21 and a tip tailstock 8, and then a three-shaft sliding table is adjusted to move the workpiece to a proper position. And the workpiece is driven by the workpiece rotating indexing shaft 7 to rotate on the A axis. And meanwhile, the fourth moving platform 12 is adjusted to feed the cutter along the Z direction, so that the center point of the cam pair of the product to be processed is overlapped with the processing point of the processing cutter of the spindle motor. The servo motor 19 drives the worm and gear indexing mechanism to perform indexing action, so that the cutter swings along the B axis, and the X/Z/A/B four-axis linkage of the machine tool can be realized. After the machining is started, only the feeding of the fourth moving stage 12 of the circular tool is required.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and equivalent alternatives or modifications according to the technical solution of the present invention and the inventive concept thereof should be covered by the scope of the present invention.

Claims (7)

1. The utility model provides a dedicated indexing mechanism of processing cambered surface cam which characterized in that:
the worm gear comprises a worm gear fixed on a machine tool base (9), a positioning central shaft (16) is arranged in the direction of the central axis of the worm gear, a fan-shaped guide rail (11) used for placing a spindle box is arranged on the outer edge of the top surface of the worm gear, a worm seat (20) is arranged on the side surface of the worm gear, a worm (17) is arranged in the worm seat (20) and meshed with the outer edge of the worm gear, and the worm (17) is driven to rotate by a worm servo motor (19) arranged on the outer side of the worm seat (20).
2. The indexing mechanism special for machining the arc cam according to claim 1, wherein:
the worm servo motor (19) adopts a 5120-wire encoder.
3. The utility model provides an use lathe of dedicated indexing mechanism of processing cambered surface cam which characterized in that:
the indexing mechanism specially used for machining the globoidal cam according to claim 1,
the machine tool comprises a machine body (1), a base (9), a three-axis sliding table and a rotary working table, wherein the three-axis sliding table is arranged above the machine body (1), the base (9) and the rotary working table are arranged on one side of the machine body (1), and the rotary working table is arranged above the base (9);
the three-axis sliding table consists of a first moving table (4), a second moving table (6), a third moving table (2), a workpiece rotary indexing shaft (7) and a tip tailstock (8), wherein the third moving table (2) is arranged above the machine body (1), the first moving table (4) is arranged above the third moving table (2), the first moving table and the third moving table form a cross sliding table, the second moving table (6) is arranged above the first moving table (4), the workpiece rotary indexing shaft (7) and the tip tailstock (8) are further arranged on the side wall of the second moving table (6), and a three-jaw chuck (24) is arranged on the workpiece rotary indexing shaft (7); the first mobile station (4) is used for adjusting the horizontal position of a workpiece to be processed; the second moving table (6) is used for adjusting the height of the workpiece to be machined and clamping and rotary feeding the workpiece to be machined; the third moving table (2) is used for adjusting the auxiliary feeding direction W of the workpiece;
the rotary working table comprises a tool electric spindle (15), an indexing mechanism (10) special for machining the arc cam according to the claims, a fourth moving table (12) and a servo motor, wherein the fourth moving table (12) is arranged above the indexing mechanism (10), one end of the fourth moving table is connected with a positioning central shaft (16), the other end of the fourth moving table is fixedly connected with a worm seat (20), the tool electric spindle (15) is arranged on the fourth moving table (12), a tool is arranged on the tool electric spindle (15) and rotates around the axis of the spindle, and the fourth moving table (12) controls the tool to realize the functions of circular feeding and tool advancing and retreating in the machining process under the driving of the servo motor (18) and is used for adjusting the front and back positions between the machining tool and a workpiece to be machined together with the third moving table (2).
4. A machine tool using an indexing mechanism dedicated to arc cam machining according to claim 3, wherein:
a z-axis screw rod (25) is arranged on the fourth moving platform (12), a main shaft mounting seat (14) is arranged on the z-axis screw rod (25), and the tool electric main shaft (15) is arranged on the main shaft mounting seat (14).
5. A machine tool using an indexing mechanism dedicated to arc cam machining according to claim 3, wherein:
the first mobile station, the second mobile station, the third mobile station and the fourth mobile station are respectively arranged on corresponding adaptive sliding rails.
6. A machine tool using an indexing mechanism dedicated to arc cam machining according to claim 3, wherein:
the three-jaw chuck and the tip tailstock are positioned on the same horizontal central axis.
7. A machine tool using an indexing mechanism dedicated to arc cam machining according to claim 3, wherein:
and a rocking handle (3) is arranged on one side of the third mobile station (2).
CN202123364488.0U 2021-12-30 2021-12-30 Indexing mechanism and machine tool special for machining cambered surface cam Active CN216882986U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202123364488.0U CN216882986U (en) 2021-12-30 2021-12-30 Indexing mechanism and machine tool special for machining cambered surface cam

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202123364488.0U CN216882986U (en) 2021-12-30 2021-12-30 Indexing mechanism and machine tool special for machining cambered surface cam

Publications (1)

Publication Number Publication Date
CN216882986U true CN216882986U (en) 2022-07-05

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ID=82208277

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202123364488.0U Active CN216882986U (en) 2021-12-30 2021-12-30 Indexing mechanism and machine tool special for machining cambered surface cam

Country Status (1)

Country Link
CN (1) CN216882986U (en)

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