KR20160109739A

KR20160109739A - Method for manufacturing gear of cyclo speed reducer

Info

Publication number: KR20160109739A
Application number: KR1020150034727A
Authority: KR
Inventors: 이지열; 최진웅; 주남식
Original assignee: 이지열; 주남식; 최진웅
Priority date: 2015-03-13
Filing date: 2015-03-13
Publication date: 2016-09-21

Abstract

A method for machining a gear of a cyclo speed reducers according to the present invention machines the gear of the cyclo speed reducer on a cutting machine (30), and includes the steps of: (a) fixing a raw material (RM) on a rotation table (31) concentrically; (b) maintaining a rotary tool post (32) of the cutting machine (30) and the table (31) eccentrically, and installing a machining tool at each of multiple spindles (33) on a circumference; and (c) machining an external gear (10) or an internal gear (20) having N tooth forms while maintaining a rotation speed of the table and the tool post differentially. Therefore, in mass-producing the gear for the speed reducer having a cycloid tooth form, the method of the present invention has the effect of promoting productivity improvement by shortening machining time since an external tooth form and an internal tooth form are generated rapidly on the basis of a number of spindles.

Description

[0001] The present invention relates to a gear cutting method for a cyclic speed reducer,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to gear processing of a speed reducer, and more particularly, to a gear processing method of a cycle reducer for mass production of a gear for a speed reducer having a cycloid tooth profile.

Cyclo speed reducers can be made compact and lightweight based on the ciclloid tooth profile, while maintaining a large reduction ratio and high durability and cushioning, they are used in various industrial machinery, measuring instruments and watches. However, it is relatively difficult to process a toothed gear of a cycloid gear mounted on a cog speed reducer. In particular, in the case of an eccentric differential speed reducer, it is difficult to expect a high productivity because high accuracy is required.

Korean Patent Registration No. 0841748 (Prior Art 1) and Korean Patent Registration No. 0754995 (Prior Art 2) are known as prior art documents related thereto.

The prior art document 1 includes a grinding machine in which a grinding blade is formed in a predetermined shape; A dressing device fixed to one side of the table to form a grinding blade of the grinding machine in a predetermined shape; A machining gear mounting portion provided on the other side of the dressing device so as to be able to reciprocate and process a cyclic gear by a polishing blade; . Accordingly, it is expected that the precise tooth surface machining process of the roughly machined cycloid gears can be performed collectively, thereby improving productivity, workability, and precision workability.

The prior art document 2 includes a step of forming a disk having a toothed gear having a toothed gear on its outer circumferential surface by primary machining to form a toothed gear, A step of cutting the non-polished portion in which the contact pressure of the first-processed toothed gear is not generated by an undercut to form a groove; And a step of grinding the to-be-polished portion of the contact portion except for the recessed portion and the abraded portion of the both-side contact portion. As a result, it is possible to obtain an economical effect by improving workability and productivity, while maintaining the performance of the planetary gear reducer.

However, the above-mentioned prior art discloses a general method such as a hobbing machine in gear cutting, and grinding is more important than cutting, thereby imposing limitations on achieving high productivity in a manufacturing field in which mass production of a cycle gear reducer must be mass-produced.

1. Korean Registered Patent No. 0841748 entitled "Cycloid Gear Processing Apparatus" (Open date: March 14, 2007) 2. Korean Registered Patent No. 0754995 entitled "Gear Shaft and Processing Method of Planetary Gear Reducer with Cycloid Tooth" (Published on Feb. 23, 2007)

In order to solve the above-mentioned problems, it is an object of the present invention to provide a gear cutting method of a cycle gear reducer which reduces a machining time of a circumferential tooth profile and an inward gear tooth profile on the basis of a plurality of spindles in mass production of gears for a speed reducer having a cycloid tooth profile. Method.

In order to achieve the above object, the present invention provides a method of machining a gear of a cycle reducer on a cutting machine, the method comprising: (a) concentrating a raw material concentrically on a rotary table; (b) eccentrically holding the table and the rotary tool bar of the cutting machine, and mounting a machining tool on each of a plurality of circumferential spindles; And (c) machining the external gear or the internal gear having N teeth while keeping the rotation speed of the table and the tool stand differentially.

In the detailed construction of the present invention, the step (b) is characterized in that the roughing tool and the finishing tool are provided coaxially with the spindle processing tool and the teeth are dimensioned by a continuous process.

As a first embodiment of the present invention. The step (c) is characterized in that when the external gear of the speed reducer is machined, N + 1 spindles are used to revolve the machining tool to the (N-1) / N rotation state of the tool table per rotation of the table.

As a second embodiment of the present invention. The step (c) is characterized in that when the internal gear of the speed reducer is machined, N-1 spindles are used to turn the machining tool to the (N + 1) / N rotation state of the tool table per one rotation of the table.

As a modification of the present invention, as a subsequent step of the step (c), the grinding is performed by using a tool holder which fixes the raw material to the table by eccentricity and rotates concentrically with the table.

As described above, according to the present invention, mass production of a gear for a speed reducer having a cicloid toothed type can quickly produce a circumscribed tooth profile and an inboard tooth profile based on a plurality of spindles, thereby improving the productivity by shortening the machining time.

Fig. 1 is an exemplary diagram of a machining method according to the present invention performed by a cutting machine
Fig. 2 is a schematic diagram showing the machining progress of the first embodiment according to the present invention. Fig.
Fig. 3 is a schematic view showing the machining concept of the second embodiment according to the present invention
4 is a schematic diagram showing a main process of the processing method according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention proposes a method of machining a gear of a cycle reducer on a cutting machine (30). The cycle reducer uses a cycloid gear as an eccentric differential type speed reducer, and achieves a high reduction ratio and quiet drive in a compact structure. The gear according to the present invention is directed to an external gear 10 and an internal gear 20 for a cycloconverter, but is not limited thereto. The universal cycle reducer has the main components as a housing with a fixed pin, an eccentric input shaft, an eccentric bearing, a cycloid disk, and an output shaft with a roller pin. In Fig. 1, the cutting machine 30 exemplifies the table 31, the tool rest 32, and the machining tool, but may be associated with components (not shown) for NC machining in addition.

Step (a) according to the present invention proceeds to a process of concentrating the raw material RM concentrically on the rotary table 31. 2 shows a state in which the raw material RM of the external gear 10 is mounted on the table 31 and a state in which the teeth are completed on the outer peripheral surface of the raw material RM. 3 shows a state in which the raw material RM of the internal gear 20 is mounted on a table and a state in which the teeth are completed on the inner peripheral surface of the raw material RM. 2 and 3, C1 represents the rotation center of the table 31 and C2 represents the rotation center of the tool rest 32. [

On the other hand, the tooth profile is broadly related to the number of teeth of the gear, and consequently includes one mountain and one goal. However, each bone can be named as a tooth for convenience in understanding the processing state.

The step (b) according to the present invention is a process of holding the table 31 and the rotary tool bar 32 of the cutting machine 30 with eccentricity and mounting the respective processing tools on the plurality of circumferential spindles 33 It goes through. The rotation center C2 of the eccentric tool rest 32 is eccentric with respect to the rotation center C1 of the table 31 in Figs. The spindle 33, which is disposed at regular intervals on the circumference of the tool rest 32, processes the raw material RM while simultaneously performing the rotational motion and the revolving motion. The machining tool provided on the spindle 33 may be divided into a roughing application and a finishing application.

The step (c) according to the present invention is a process for machining the external gear 10 or the internal gear 20 having N teeth and keeping the rotational speeds of the table 31 and the tool rest 32 differently It goes through. 2, the external gear 10 having 10 teeth is machined on the outer circumferential surface, and the internal gear 20 having 10 teeth on the inner circumferential surface is machined according to Fig. However, the number of spindles 33 in the processing of the external gear 10 and the internal gear 20 is set different from the number of teeth, and the rotational speed is also different. The spindle 33 rotates at the same speed and rotates the raw material RM to perform cutting of the tooth profile.

The step (b) of the present invention is characterized in that the roughing tool 35 and the finishing tool 36 are provided coaxially with the spindle 33 and the teeth are dimensioned by a continuous process do. With the roughing tool 35 on the lower side of each spindle 33 coaxially with the belt 46 on the upper side. According to this method, it is advantageous to improve the productivity by excluding the time for replacing the processing tool.

As a first embodiment of the present invention. (N-1) / N rotations of the tool rest 32 per revolution of the table 31 using N + 1 spindles 33 when processing the external gear 10 of the speed reducer The machining tool is caused to revolve. As shown in Fig. 2, the external gear 10 having 10 tooth profiles is machined on the tool rest 32 on which 11 spindles 33 are mounted. That is, the spindle 33 of the tool rest 32 eccentrically moves from the table 31 and performs idle motion at a speed slightly lower than the rotation speed of the raw material RM. The spindle 33 proceeds to the path of the outer cycloid curve and the cutting is performed.

Referring to FIG. 4, it can be understood that when the raw material RM of the table 31 is observed in a stationary state, the spindle 33 carries out the cutting operation while reversely rotating at a relatively low speed of (N-1) / N ratio. The machining tool of the spindle 33 extending from S1 to S11 is cut while sequentially sprouting the teeth from the marks T1 to T10. Of course, the rotational speed of the table 31 is determined according to the situation of the field, and accordingly the rotational speed of the tool rest 32 is also determined.

As a second embodiment of the present invention. (N + 1) / N rotations of the tool rest 32 per revolution of the table 31 using N-1 spindles 33 when the internal gear 20 of the speed reducer is machined The machining tool is caused to revolve. As shown in Fig. 3, the internal gear 20 having 10 tooth profiles is machined on the tool rest 32 on which the nine spindles 33 are mounted. That is, the spindle 33 of the tool rest 32 eccentrically moves from the table 31 and performs idle motion at a speed slightly higher than the rotation speed of the raw material RM. The spindle 33 proceeds to the path of the inner cycloid curve and the cutting is performed.

Based on the same principle as described above with reference to Fig. 4, the machining tool of the spindle 33, which extends from S1 to S9, carries out cutting while sequentially orbiting the teeth from the marks T1 to T10. However, when the raw material RM is observed in a stationary state, there is a difference that the spindle 33 rotates at a relatively high speed of (N + 1) / N ratio.

In any of the cases of the present invention, the number of cutting operations can be greatly reduced as compared with the use of the conventional one processing tool.

As a modification of the present invention, as a subsequent step of the step (c), grinding is carried out by using a tool rest 32 which is eccentrically fixed to the table 31 with the raw material RM and rotated concentrically with the table 31 . In the actual cycle reducer, the cycloid disk performs eccentric motion about the rotation axis between the input shaft and the output shaft. The eccentric motion of the tool rest 32 is eliminated and the eccentric movement of the raw material RM fixed to the table 31 is caused to perform grinding. Grinding is a kind of superficial process that ensures the surface roughness required for final products.

As described above, according to the present invention, it is possible to reduce the error of the cycloid curve by giving similar conditions to the actual drive of the speed reducer in any machining of roughing, finishing and grinding, and it is possible to reduce errors in the quality And productivity can be expected.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. It is therefore intended that such variations and modifications fall within the scope of the appended claims.

10: external gear 20: internal gear
30: Cutter 31: Table
32: tool stand 33: spindle
35: Roughing tool 36: Finishing tool
RM: Raw material C1, C2: Center of rotation

Claims

A method of machining a gear of a cycle reducer on a cutting machine (30), comprising:
(a) concentrating the raw material RM concentrically on the rotary table 31;
(b) eccentrically holding the table (31) and the rotary tool base (32) of the cutting machine (30) and mounting a machining tool on each of a plurality of circumferential spindles (33); And
(c) machining the external gear (10) or the internal gear (20) having N teeth while maintaining the rotation speeds of the table (31) and the tool rest (32) Of the gear of the cycle reducer.

The method according to claim 1,
Wherein the step (b) comprises setting the roughing tool (35) and the finishing tool (36) coaxially with the machining tool of the spindle (33) and adjusting the size of the teeth by a continuous process .

The method according to claim 1,
(N-1) / N rotations of the tool rest 32 per revolution of the table 31 using N + 1 spindles 33 when processing the external gear 10 of the speed reducer And the machining tool is revolved in a state that the machining tool is rotated.

The method according to claim 1,
(N + 1) / N rotations of the tool rest 32 per revolution of the table 31 using N-1 spindles 33 when the internal gear 20 of the speed reducer is machined And the machining tool is revolved in a state that the machining tool is rotated.

The method according to claim 1,
Wherein the grinding is performed by using a tool base (32) which is eccentrically fixed to the table (31) and rotates concentrically with the table (31) as a subsequent step of the step (c) Of the gear.