JPH05277610A - Method for finishing tooth surface of gear - Google Patents

Abstract

PURPOSE:To provide the method for finishing the shape by pressing the roller while rotating in order to improve the precision of shape roughly machined to the approximate shape with the roller having the tooth shape of gear. CONSTITUTION:After positioning the center line of the dedendum of a gear 3 to be machined after roughly machined and the center line of a roller having the tooth shape of the above gear to the same center line, the axis of the gear 3 to be machined and the axis of the roller 2 are synchronously rotated at the position preparing for being brought in contact with.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to smooth machining of tooth surfaces of gears used in automobiles and the like and improvement of tooth profile accuracy.

[0002]

2. Description of the Related Art In conventional gear machining, a roughing machine such as a hobbing machine is used for rough machining, and gears related to automobile transmissions have high accuracy in terms of tooth surface in terms of noise, friction heat and durability. Problems have been raised, and in the current state of the art, in the gear rolling method, improvement in accuracy due to swelling is awaited. The solution was to perform secondary finishing using an expensive shaping cutter, and to maintain the accuracy by taking a means of tooth grinding when necessary, but the cost of cutting tools is high and the cost is high. there were.

[0003]

As a method for smoothing the tooth flanks of gears and satisfying the requirements for accuracy, a shaping finishing method has been generally used after rough machining with a hobbing machine as described above. The cutter is expensive to manufacture, and the conventional finish rolling method gradually squeezes it by meshing to raise it, so even if the die is manufactured to a regular involute curve, the tooth profile of the gear will not be the correct involute curve. Also, the involute curve changes and the tooth profile changes due to the change in the crushing allowance. The present invention has been proposed in order to solve the above problems, because it does not utilize the meshing of the die and the gear as in the finish rolling method, the present invention is that the tooth-shaped roller is directly applied to the gear. Since the ball is crushed by hitting, there is no change in the involute curve due to the change in the crushing allowance, and the roller can be manufactured in any tooth profile. The present invention has been made in order to provide stable accuracy because there is no variation in accuracy because the roller is easy to manufacture and the tooth profile of the gear does not change even if the crushing allowance changes.

[0004]

In order to solve the above-mentioned problems, in the gear tooth surface finishing method of the present invention, a base body for forming a tooth profile of a gear to be machined after rough machining which is held in advance, A finishing roller holder and a gear to be machined after rough machining are provided by providing a rotating body through a pin that supports a roller having an arbitrary tooth profile on the outer circumferential edge of a finishing roller holder that has rotation when forming a tooth profile. And a synchronous rotation of the finishing roller holder and an arbitrary feed in the direction of the tooth trace are started.

[0005]

Because of the above measures, in order to use the present invention, the finishing roller holder is temporarily stopped at the position closest to the gear to be machined after rough machining. Although not shown, operate the gear positioning device to align the center line of the tooth profile roller of any shape with the center line of the bottom of the gear to be aligned on the concentric line, and then move it to the position where the roller and the gear to be processed come into contact with each other. Clamp the gear to be processed. After rotating the finishing roller holder, start feeding in the direction of the tooth trace with any cut.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings. FIGS. 1 and 2 clearly show the basic principle of a tooth surface finishing method for gears according to the present invention, and FIG. FIG. 2 is a front view illustrating a preferred embodiment of FIG. 2, and FIG. 2 is a plan view illustrating an enlargement of a partly cutaway main part. According to the invention,
Although the base body for finishing the rough-worked work gear 3 is not shown, the rough-worked work gear 3 is set on the arbor 4 and the main body on which the finishing roller holder 1 is mounted is closest to the work gear 3. Stop at the position once. Next, although not shown, the gear positioning device is operated, and the roller 2 having the tooth profile shown in FIG. 2 is rotatably provided via the pin 5, and the tooth profile center line of the roller 2 having this tooth profile is After aligning the center line of the bottom of the rough-processed gear 3 with the concentric line, the roller 2 having a tooth profile is moved until it comes into contact with the rough-processed gear 3, and the gear is clamped. When the shaft of the finishing roller holder 1 makes one revolution, the shaft of the gear 3 to be rough-processed makes one tooth rotation, and the shaft and the shaft are synchronously rotated. When the feed of the roller is started, the processed gear 3 after the rough machining has the tooth profile of the roller 2 crushed by the roller 2 having the tooth profile, and the tooth profile of the roller 2 having the tooth profile is roughly machined. 3 is transferred to the surface of the tooth surface. Since the tooth profile accuracy is determined by the tooth profile accuracy of the roller 2, there is no need to increase the tooth profile accuracy for rough cutting because it is not affected by the crushing allowance. Regarding the pitch accuracy, in our trial processing, JIS2 class measurement results were obtained.

Although the center of the roller 2 and the center of the rough-processed gear 3 are concentric with each other, a finishing method of changing the pressure angle of the gear 3 by shifting the center of the roller is used. It is possible to shift the synchronization of the rotation of the finishing roller holder 1 and the rotation of the gear 3 to be processed while starting the feed, so that it is possible to beat the tooth traces, so that it is possible to process to a bias tooth profile. is there. Further, not only the spur gear but also the finishing processing method of the helical gear is possible, and the present invention is not limited to the gears and can be applied to the finishing processing method of different shapes (for example, sprockets).

[0008]

As described above, according to the present invention, since the roller structure which has never existed in the prior art is adopted, the tooth profile accuracy is not varied due to the meshing state of the gears and the rise of the teeth as in the case of the round die and the rack die. It is obvious that it is excellent in obtaining a stable tooth profile that satisfies the above condition, and the process such as a conventional die and a shaping cutter such as a correction trial is expensive, but the finishing method developed by the present invention. Since the roller manufacturing cost is low and the tooth profile of the gear is used as it is, the roller product cost can be reduced and stable gear accuracy can be obtained.

[Brief description of drawings]

FIG. 1 is a front view showing a preferred embodiment of the present invention.

FIG. 2 is a plan view showing an enlargement of a partly cutaway main part of the present invention.

[Explanation of symbols]

 1 Finishing roller holder 2 Roller with tooth profile 3 Worked gear after rough machining 4 Arbor 5 pin

Claims (1)

[Claims] 1. A base body for forming a tooth profile of a gear to be machined (3) which has been held in advance and a finishing roller holder (1) having a rotation for forming the tooth profile in the outer diameter direction. A rotary body is provided via a pin (5) supporting a roller (2) having a tooth profile of any desired tooth profile, and the finishing roller holder (1) and the gear to be machined (3) after rough machining are synchronously rotated. A method for finishing a tooth surface of a gear, which is characterized in that the feeding is started in the tooth trace direction.