JPS60242913A - Machining method for resin coated gear - Google Patents

Abstract

PURPOSE:To machine a gear having no dispersion of the thickness of its coating film by meshing a shaving cutter combined with a phasing gear based upon a reference given by the specified tooth surface corresponding to a part of the gear to be machined which has not yet been coated with resin. CONSTITUTION:A gear 7 to be machined having tooth surface 8 coated with resin film of uneven thickness is set in such a way that it is meshed with a cutter (not shown in the drawing). When cutting is made in the direction of Y axis until a tooth surface 10 not relating to the thickness of the coating film because of having not yet been coated meshed with the tooth surface 5 of a phasing gear 2, the coating tooth surface 9 of the gear 7 to be machined is cut while being slided in the direction of Z axis due to the rotary cutting motion of the tooth surface 2 of a shaving cutter 1 with the result that the accurate tooth surfaces coated uniformly with films of h5 in thickness can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to finishing processing of the tooth surface of a gear whose tooth surface is coated with a resin, using a shaving cutter that can make the coating film uniform and the tooth surface precision high. It is about the method.

Conventional technology Conventionally, in order to improve the various performances of gears by ensuring the thickness of the resin coating film, finishing of the tooth surfaces of resin-coated gears after coating has been done using a cutter such as a hob or a gear shaver. The tooth profile has been modified,
A method of ensuring the precision of the coated tooth surface is to further perform finishing processing such as shaving processing as necessary. Figure 6 shows a conventional tooth surface finishing method, in which the blade surface (D) of a shaving cutter (N) fixed to the axis fB) is attached to the tooth surface (C) of a resin-coated gear to be machined (C). This indicates that the trout is processed in a normal meshing state by shaving processing, and even if it is processed to match the phase of the tooth profile (I) before being coated with resin by hobbing or gear shaver, it is actually It was a difficult task to precisely match the phase of the tooth profile (group) because of the difference in the thickness of the resin coat film (FL (G). Therefore, in the end, the result was that the tooth profile was machined after the resin coat tooth surface. The relationship between the film thickness (hl) of the advancing surface (F') in the advancing direction where the tooth surface is rotary cut and the film thickness (h2) of the retreating surface (G') on the opposite side is hl.
〉h2, the difference will be large), even if the above-mentioned hob or gear shaver processing is further performed using the shaving cutter shown in Fig. 6, the conventional method will not remove the resin. Machining follows the tooth surfaces with different coating thicknesses, and the advancing surface of the tooth profile (
The F′) side and the retreating surface (σ) side are machined to the same machining allowance, and the difference between the film thickness (h+) and film thickness (h2) is not resolved.
Although the precision of the tooth surface is improved by shaving, it is impossible to correct the thickness of the resin coating film on the tooth surface, and there is a drawback that variations in film thickness cannot be reduced.

Purpose of the Invention In view of the drawbacks of the processing method using the conventional apparatus described above, the present invention provides a method to finish the tooth surface of a gear coated with a resin so that there is no difference in the thickness of the resin coating film when a shaving cutter or the like is engaged with the tooth surface. In other words, a phasing gear is combined with a shaving cutter to prevent the difference between the film thickness on the forward side being cut and the film thickness on the opposite side, the retreating side. The shaving cutter can be engaged with the predetermined tooth surface of the part that is not covered.By ensuring a uniform coating film thickness with no variation, the gear's wear resistance, rolling fatigue resistance, and working life are improved. 2. It is an object of the present invention to provide a method for processing a resin-coated gear that can improve the amount of elastic deformation and the noise prevention effect of the gear.

Structure of the Invention As described in the claims, the present invention comprises making the pitch circle and number of teeth of a shaving cutter and a phasing gear equal, and combining the two on the same axis to form a cutter. After applying a resin coat to the tooth surface of the gear, leaving an unattached portion around the entire circumference of the gear to be machined, which is part of the tooth width.

11. Engaging the positioning gear with the unattached portion;
By cutting the resin coated film with the cutter, the variation in film thickness between the forward and backward surfaces can be reduced and a uniform tooth surface can be ensured.

Embodiments Below, embodiments of the present invention will be explained with reference to FIGS. 1 to 4. FIG. 1 shows a first embodiment of a processing method using a resin-coated gear and a cutter according to the present invention, in which a shaving cutter 1 and a phasing gear 2 are fixed to a cutter shaft 3. are the same pitch circle (P), have the same number of teeth, and as shown in Fig. 2, the tooth surface 4 of the shaving cutter 1 is The cutter 6 is formed such that the tooth profile of the cutter 6 and the tooth profile of the tooth surface 5 of the phasing gear 2 are combined in a symmetrical phase relationship so that both rotate in the same direction.

As shown by the chain lines in FIGS. 3 and 2, the gear 7 to be machined is coated with a soft resin. The coated tooth surface 1o exists, and the coated tooth surface 9 and the uncoated tooth surface 10 are formed to have the same pinch circle (0), and as shown in FIG.
The shaving tooth surfaces 9 are set so that they are engaged and shaving is performed.

As shown in FIG. 4, a coating film is formed on the rough-machined tooth surface 11 in the pre-process of the shaving process.
As shown in FIG. 1, the workpiece gear 7 having resin-coated tooth surfaces 8 with different film thicknesses (h3) and (h4) is set to mesh with the cutter 6, and the thickness of the coated film is The coated tooth is cut by cutting in the direction of the arrow (Y) shown in FIG. 1 until the uncoated tooth surface 1o, which is not related to The coated tooth surface 9 of the processed gear 7 is cut while being slid in the direction of the arrow (Z) as the gear rotates.
The film thickness (h3) on the advancing surface 12 and the film thickness (h4) on the receding surface 13 side of the tooth profile shown in FIG. Surface accuracy can be improved.

FIG. 5 shows a second embodiment of the gear 14, which has a different coating shape and is coated with a soft resin.
Having an uncoated tooth surface 16 around the entire circumference in the center of the tooth width,
The other parts including both ends are formed to be coated tooth surfaces 15, in which case the phasing gear 2 shown in FIG. 1 is installed in the center of the shaving cutter 1, It is set to mesh with another cutter (not shown), and the shaving process is performed using the same structure and method as in the first embodiment.

Effects of the Invention The present invention has the above-described configuration 1, and in finishing the tooth surface of a gear coated with a soft resin, the phasing gear of a shaving cutter and the unattached portion of the resin coated gear are treated. Because the resin-coated tooth surface is shaved for meshing with the tooth surface, it has the effect of ensuring an even film thickness without any variation in the resin-coat film thickness. Specifically, a thin, uniform coating film is effective for gear wear resistance and rolling fatigue life, and a thick, uniform coating film can be expected to have a large elastic deformation, which can be expected to have a noise prevention effect. It is effective because it allows the coating film thickness to be adjusted to these usage conditions without variation.
As mentioned above, this has the effect of improving the performance of the gear in many ways, such as the wear resistance of the gear and the prevention of noise.

[Brief explanation of drawings]

Fig. 1 is a side view showing an aspect of the processing method according to the configuration of the first embodiment of the present invention, and Fig. 2 is an enlarged schematic diagram showing the phase and meshing of the tooth flanks of the embodiment shown in Fig. 1. Figure 3 is a schematic partial view of the tooth surface of the gear to be machined shown in Figure 1;
The figure is a partial schematic enlarged view of the side surface of the coated tooth shown in FIG. 3, FIG. 5 is a partial schematic partial view of the coated tooth surface showing the second embodiment, and FIG. 6 is a conventional machining method using a cutter. FIG. 7 is a partially schematic enlarged view of the side surface of the coated tooth shown in FIG. 6. 1: Shaving cutter, 2: Phasing gear, 3: Shaft, 6: Cutter, 7: Gear to be machined, 9: Resin coated tooth surface, 10: Unattached part, P. Pitch circle, h5: film thickness. Patent Applicant Toyota Motor Corporation Agent Osamu Ichikawa Yoshido Tatsuya Endo Figure 1 Figure 4 Figure 5 Figure 7

Claims (1)

[Claims] The pitch circle and number of teeth of the shaving cutter and the phasing gear are made equal, and the above two are combined to form a cutter, and a part of the tooth width of the shaving cutter and the phasing gear are placed on the same axis, and a cutter is formed on the tooth surface of the to-be-processed gear, and a part of the tooth width is applied to the entire circumference of the to-be-processed gear. Processing of a resin-coated gear, characterized in that after applying a resin coat to the unattached portion, the positioning gear is engaged with the unattached portion and the resin coat film is cut by the cutter. Method.