Shaft and manufacturing method thereof

• US 20040063506A1
• Filed: 09/30/2003
• Published: 04/01/2004
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: Toyoda Koki Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyoda Koki Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yamato, Hiroki, Ohwaki, Tomonori, Ichikawa, Kazuyuki
• Granted Patent: US 7,052,402 B2
• Time in Patent Office: Days
• US Class Current: 464/182
• CPC Class Codes: F16C 2240/70 Diameters; Radii
• CPC Class Codes: F16C 2361/41 Couplings
• CPC Class Codes: F16C 3/02 Shafts; Axles
• CPC Class Codes: F16D 1/06 for attachment of a member on a shaft or on a shaft-end attachment of marine propellers on shafts B63H23/34
• CPC Class Codes: F16D 1/072 involving plastic deformation plastic welding F16D1/068
• CPC Class Codes: F16D 1/0858 due to the elasticity of the hub (including shrink fits)
• CPC Class Codes: F16D 1/10 Quick-acting couplings in which the parts are connected by simply bringing them together axially
• CPC Class Codes: F16D 2001/103 the torque is transmitted via splined connections
• CPC Class Codes: F16D 3/2055 having three pins, i.e. true tripod joints
• CPC Class Codes: Y10T 403/7035 Specific angle or shape of rib, key, groove, or shoulder

Abstract

A shaft has a shank with a splined portion and a large diameter portion formed in an outer peripheral surface of the shank, the large diameter portion having a diameter that is larger than a diameter of an external periphery of the splined portion. A tapered portion is provided at a side surface of the large diameter portion on the splined portion side. This tapered portion stops a fitting member that is fitted onto the splined portion. In addition, a cut back portion formed at an end portion of the splined portion at the large diameter portion side and the tapered portion are interposed by and continuously connected by a first curved portion, a flat portion and a second curved portion.

Claims

1. A shaft having a shank with a splined portion that is spline engaged with a fitting member, and with an external diameter portion that is formed with a distance of separation from the splined portion, both the splined portion and the external diameter portion being formed in an outer peripheral surface of the shank, comprising:

any one of a curved portion, a plurality of curved portions, and a plurality of curved portions and at least one straight portion, that extend continuously so as to connect a cut back portion formed at an end portion of a groove portion of the splined portion and the external diameter portion.

2. The shaft according to claim 1, further comprising:

a large diameter portion which has a diameter that is larger than a diameter of an external periphery of the splined portion and which is formed at an end portion of the external diameter portion at the splined portion side; and

a tapered portion which stops the fitting member and which is provided at a side surface of the large diameter portion at the splined portion side.

3. The shaft according to claim 2, wherein an end portion at the external diameter portion side of the curved portion is formed so as to be further from a shaft axis of the shank than the cut back portion.

4. The shaft according to claim 1, wherein two of the curved portion are provided.

5. The shaft according to claim 2, wherein two of the curved portion are provided.

6. The shaft according to claim 3, wherein two of the curved portion are provided.

7. The shaft according to claim 1, wherein two of the straight portion are provided.

8. The shaft according to claim 2, wherein two of the straight portion are provided.

9. The shaft according to claim 3, wherein two of the straight portion are provided.

10. A manufacturing method for manufacturing the shaft as in claim 1, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

11. A manufacturing method for manufacturing the shaft as in claim 2, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

12. A manufacturing method for manufacturing the shaft as in claim 3, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

13. A manufacturing method for manufacturing the shaft as in claim 4, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

14. A manufacturing method for manufacturing the shaft as in claim 5, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

15. A manufacturing method for manufacturing the shaft as in claim 6, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

16. A manufacturing method for manufacturing the shaft as in claim 7, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

17. A manufacturing method for manufacturing the shaft as in claim 8, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

18. A manufacturing method for manufacturing the shaft as in claim 9, comprising the steps of:

forming the splined portion with a predetermined shape by cold forging, machining and component rolling;

forming the curved portion by component rolling; and

conducting quenching.

19. The manufacturing method for the shaft according to claim 10, further comprising the step of:

conducting shot peening of the shaft.