Method for manufacturing hypoid gear

Patent metadata

Field	Value
Publication number	US-12017292-B2
Application number	US-202017594105-A
Country	US
Kind code	B2
Filing date	Mar 16, 2020
Priority date	Apr 4, 2019
Publication date	Jun 25, 2024
Grant date	Jun 25, 2024

Abstract

A method for manufacturing a hypoid gear includes: a tooth cutting step of machining a shape of a tooth of the hypoid gear; a surface treatment step of forming a third intermediary gear provided with a hardened layer on a surface of the tooth; a lapping step of machining the third intermediary gear using an abrasive particle having a diameter of 14 μm or less to form a fourth intermediary gear; and a shot peening step of spraying a particle having a diameter of 160 μm or less onto the fourth intermediary gear.

First claim

The invention claimed is:

1. A method for manufacturing a hypoid gear, the method comprising:
a tooth cutting step of machining a shape of a tooth of the hypoid gear;
a surface treatment step of forming a first intermediary body provided with a hardened layer on a surface of the tooth;
a lapping step of machining the first intermediary body using an abrasive particle having a diameter of 14 μm or less to form a second intermediary body; and
a shot peening step of spraying a particle having a diameter of 160 μm or less onto the second intermediary body.

2. The method for manufacturing the hypoid gear according to claim 1 , wherein the surface treatment step includes at least one of a heat treatment step and a shot peening step of spraying a particle having a predetermined diameter.

3. The method for manufacturing the hypoid gear according to claim 2 , wherein in the lapping step, given that a diameter of the abrasive particle is R (μm) and a rotational speed of a drive pinion is N (rpm), the following relational expression is satisfied:
33,000≤R×N≤50,000.

4. The method for manufacturing the hypoid gear according to claim 3 , wherein the diameter of the abrasive particle is 14 μm, and the rotational speed of the drive pinion is 2,400 rpm.

5. The method for manufacturing the hypoid gear according to claim 4 , wherein the hypoid gear after the shot peening step has a surface roughness of 0.8 μm or less.

6. The method for manufacturing the hypoid gear according to claim 5 , wherein the hypoid gear is a pinion gear or a ring gear in a differential.

7. The method for manufacturing the hypoid gear according to claim 4 , wherein the hypoid gear is a pinion gear or a ring gear in a differential.

8. The method for manufacturing the hypoid gear according to claim 3 , wherein the hypoid gear after the shot peening step has a surface roughness of 0.8 μm or less.

9. The method for manufacturing the hypoid gear according to claim 3 , wherein the hypoid gear is a pinion gear or a ring gear in a differential.

10. The method for manufacturing the hypoid gear according to claim 2 , wherein the hypoid gear after the shot peening step has a surface roughness of 0.8 μm or less.

11. The method for manufacturing the hypoid gear according to claim 2 , wherein the hypoid gear is a pinion gear or a ring gear in a differential.

12. The method for manufacturing the hypoid gear according to claim 1 , wherein in the lapping step, if a diameter of the abrasive particle is R (μm) and a rotational speed of a drive pinion is N (rpm), the following relational expression is satisfied:
33,000≤R×N≤50,000.

13. The method for manufacturing the hypoid gear according to claim 12 , wherein the diameter of the abrasive particle is 14 μm, and the rotational speed of the drive pinion is 2,400 rpm.

14. The method for manufacturing the hypoid gear according to claim 12 , wherein the hypoid gear after the shot peening step has a surface roughness of 0.8 μm or less.

15. The method for manufacturing the hypoid gear according to claim 12 , wherein the hypoid gear is a pinion gear or a ring gear in a differential.

16. The method for manufacturing the hypoid gear according to claim 1 , wherein the hypoid gear after the shot peening step has a surface roughness of 0.8 μm or less.

17. The method for manufacturing the hypoid gear according to claim 16 , wherein the hypoid gear is a pinion gear or a ring gear in a differential.

18. The method for manufacturing the hypoid gear according to claim 1 , wherein the hypoid gear is a pinion gear or a ring gear in a differential.

19. The hypoid gear of claim 1 , wherein the first intermediary body and the second intermediary body are gear pairs of intermediary bodies of the pinion gear of a rear differential unit and the intermediary bodies of the ring gear of the rear differential unit respectively.

Assignees

• Mazda Motor

Inventors

• Noguchi Yoshihito
• Takatsu Ryo
• Ueda Isamu
• BANDOU Takeo
• Oka Nobuyuki

Classifications

• B24C11/00

  Selection of abrasive materials {or additives} for abrasive blasts (polishing compositions C09G) · CPC title

• B24C1/10 Primary

  for compacting surfaces, e.g. shot-peening (for deforming sheet metal, tubes or profiles B21D31/06; as a metallurgical treatment C21D7/00, C22F1/00) · CPC title

• B24B37/02

  designed for working surfaces of revolution · CPC title

• B23P15/14

  gear parts, e.g. gear wheels · CPC title

• B23F19/02

  Lapping gear teeth · CPC title