JPH0417933A - Indexing method in gear form rolling device - Google Patents

Abstract

PURPOSE:To prevent a pitch from deviating in time of initial indexing for forming a gear by pushing a form rolling die to a form rolling billet to form a groove, then, fixing the distance between the form rolling billet and the form rolling die and forming the groove for progressive indexing on the outer periphery of the form rolling billet. CONSTITUTION:A die holder 3f is pushed by a hydraulic cylinder 3c into a place to form a tooth form, but on the way to that place or when the form rolling die 3a strikes at a form rolling machine 3b to obtain a groove 1c, the die holder strikes at a wedge-shaped stopper 3e and is stopped and at the same time the form rolling billet or the form rolling die 3a is rotated to form the groove 1c uniformly on the outer periphery of the form rolling billet 3b. Then, the hydraulic cylinder 3d is actuated to release the wedge-shaped stopper 3e. This release advances the stop die holder to form the tooth form and gives a nice tooth form.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a method for cutting a gear rolling device.

(Prior Art) When a gear is formed using a gear rolling device, a tooth profile is formed by rotating and pushing one of a rolling die or a circular rolling material.

In the basic diagram of rolling forming shown in Fig. 5, rolling die 5
When the rolling material 5a and the rolling material 5b are gradually pushed in, grooves 50 corresponding to the number of teeth are gradually formed on the outer periphery of the rolling material, and a tooth profile is formed in which the grooves 50 become the root portions of the teeth.

(Problem to be Solved by the Invention) However, since the tooth profile rolling method described above is a forming method in which one of the rolling die or the rolling material is gradually pushed in while rotating, the pushing speed is fast (as a result, the rolling die 5a The center-to-axis distance with the rolling material 5b changes greatly between the initial stage and the final stage of forming, and therefore the pitch of the grooves changes, causing misalignment because the groove cannot be cut properly at the initial stage of rolling.

Furthermore, even if the cutting is successful, the pitch of the groove changes, resulting in an unbalance in volume between each tooth profile.

As a result, as shown in Fig. 6, the underfill that occurs at the tip of the tooth profile 6a becomes large, the dimensional accuracy of the gear deteriorates, and the load applied to the rolling die becomes excessively variable, making it more likely to break. There is a problem.

The technical object of the present invention is to provide a cutting method for a gear rolling device that does not cause pitch deviation during initial cutting when forming gears using a gear rolling device and has good dimensional accuracy of the gear after forming. .

[Structure of the invention]

(Means to solve the problem) The technical measures taken to solve the problem are as follows. In other words, in the dividing method of a gear rolling device that rolls gears, when the number of teeth is divided equally between the rolling material and the rolling die, the number of teeth is 0.3 without rotating the rolling material and the rolling die. ~0
．． 5 mm deep (push to fix the distance between the axes of the rolling material and the rolling die, then rotate the rolling material or the rolling die to form a groove on the outer periphery of the rolling material in the same way as above) This is a method of dividing the amount.

(Function) A rolling die is pushed into the rolling material by 0.3 to 0.5 mm to form a groove, and then the distance between the rolling material and the rolling die is fixed, and the rolling die is sequentially cut. By forming the grooves on the outer periphery of the rolled material, the distance between the shafts is fixed, allowing for correct cutting, the depth of the grooves is also constant, there is no pitch deviation, and there is no volume imbalance. .

If uniform grooves are formed in this way and then the tooth profile is formed using a gear forming device with the distance between the shafts set free, a correct tooth profile can be formed.

(Example) Examples will be described below.

In this embodiment, the purpose is to perform cutting with high accuracy at the initial stage of rolling, and as shown in Fig. 1, the rolling die 1a is not rotated on the rolling material 1b, and a fixed amount of 0.3 to 0.5 mm is cut into the rolling material 1b. is pushed in to form a full 10, and then the rolling material 6 or the rolling die 1a is rolled to form grooves at a uniform pitch on the outer periphery of the rolling material, and then the rolling die is further pushed in to form a tooth profile. This provides a good tooth profile with no groove pitch deviation or pitch difference.

FIG. 2 shows a basic example of this embodiment, in which the die holder 21 is advanced by a hydraulic cylinder 2C using a hydraulic mechanism, and when the rolling die 2a has formed the groove 1c in the rolling material 2b, a center block is attached. The pulp 2d is operated, the die holder 2f is stopped, and at the same time the rolling material or the rolling die is rotated, and after the groove 1c has been uniformly formed on the outer periphery of the rolling material, the valve 2d with center block is operated and the die is rotated. The tooth profile is obtained by moving the holder 2f forward.

However, with this device, when the rolling die hits the rolled material,
Or, when forming the grooves on the outer periphery, there may be variations in the load, and the die holder 2f may be returned and the grooves 1c may not be formed uniformly.

Therefore, in order to solve the above-mentioned problems, the cutting mechanism of the rolling device is shown in FIGS. 3 and 4.

In FIG. 3, the die holder 3f is pushed by the hydraulic cylinder 30 to the point where the tooth profile is to be formed, but in the middle of this, that is, at the point where the rolling die 3a hits the rolling machine 3b and obtains the groove IC, When the die holder 3f hits the wedge-shaped stopper 3e, the rolling material 3b or the rolling die 3a is simultaneously rotated to uniformly form the grooves 1c on the outer periphery of the rolling material. Next, the hydraulic cylinder 3d is operated to release the wedge-shaped stopper 3e. Dice holder 3f, which had stopped due to this release,
moves forward to form a tooth profile and obtain a good tooth profile.

In addition, in Fig. 4, the die holder 4f is connected to a hydraulic cylinder 4d.
The rolling die 4a is pushed into the rolling material 4b to the point where the groove 10 is formed, and at the same time the rolling material or the rolling die is rotated to uniformly form the groove 1c on the outer periphery of the rolling material. is a stopper. Thereafter, the die holder 4f is pushed in by the hydraulic cylinder 4c until a predetermined tooth profile is obtained, thereby obtaining a good tooth profile.

(Effects of the Invention) The present invention has the following effects. That is, (1) the dimensional accuracy of the gear, especially the pitch error due to pitch deviation at the time of initial cutting, is improved.

(2) Changes in the load applied to the rolling die are uniform, improving the life of the rolling die.

(3) There is no volume imbalance between tooth profiles due to pitch deviation during initial cutting, and rolling defects, especially underfill variations, can be eliminated.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a basic example of this embodiment, Fig. 2 is an explanatory diagram of this embodiment, Figs. 3 and 4 are explanatory diagrams of other embodiments, and Fig. 5 is an explanatory diagram of a conventional example. , FIG. 6 is an external view of the tooth profile when implemented in a conventional example. la, 5a-rolling die, lb, 5b...rolling material,
lc, ld... split groove.

Claims (1)

[Claims] In the dividing method of a gear rolling device that rolls and forms gears, when the number of teeth is divided equally between the rolling material and the rolling die, the rolling die is pushed into the rolling material by a certain amount without rotating, and the The distance between the axes of the rolling material and the rolling die is fixed, and then the rolling material or the rolling die is rotated to form a groove on the outer periphery of the rolling material in the same manner as described above to divide the tooth profile. How to cut gears using gear rolling equipment.