Patent EP0161624A2 successfully refreshed from Google Patents.
EP0161624A2
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EP
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Method of producing a camshaft
Assignee: Toyota Motor Corp
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Filing: 1985-05-07
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Granted: —
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Expires: 2005-05-07
Abstract
Abstract A method of producing a cast iron camshaft (1) comprising the steps of applying a high-density energy source, such as a TIG arc (3), a laser beam, and an electron beam over the entire sliding surface of a cam (2) to melt the surface portion and cooling the cam by dissipating the localized heat through the camshaft itself so as to form a double structure hardened layer (7) consisting of a chilled layer (8) having a large amount of cementite and a hardened layer (9) of martensite. This method omits the preheating of the camshaft prior to the high-density energy irradiation.
Inventors
- 👤 Akiyoshi Morita
- 👤 Hideo Nonoyama
- 👤 Toshiharu Fukuizumi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 06:51
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/30; C21D5/00; F; F16; F16H; F16H53/00; F16H53/02; Y; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2101
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
103 words
A method of producing a camshaft (1) of cast iron comprising applying a high-density energy source, such as a TIG arc, a laser beam, and an electron beam on the whole circumferential sliding surface of a cam (2) of the camshaft (1) to melt the surface portion, and cooling the cam by dissipating localized heat through the camshaft itself to form a double structure hardened layer (7) consisting of chilled layer (8) which is melted and cooled and has a large amount of cementite and a hardened layer (9) which is heated above austenizing point and then cooled to form a martensite layer.
Claim 2
Independent Claim
103 words
A method of producing a camshaft (1) of cast iron comprising applying a high-density energy source, such as a TIG arc, a laser beam, and an electron beam on the whole circumferential sliding surface of a cam (2) of the camshaft (1) to melt the surface portion, and cooling the cam by dissipating localized heat through the camshaft itself to form a double structure hardened layer (7) consisting of chilled layer (8) which is melted and cooled and has a large amount of cementite and a hardened layer (9) which is heated above austenizing point and then cooled to form a martensite layer.
Claim 3
Dependent Claim
35 words
A method according to claim 1, wherein said chilled layer (8) has a thickness of from 0.3 to 1.5 mm and said hardened layer (9) has a thickness of from 0.3 to 2.0 mm .
Claim 4
Dependent Claim
43 words
A method according to claim 1 further comprising, before said applying step, drilling said camshaft (1) to form a longitudinal oil bore (5) along the axis of said camshaft and a radial oil hole (6) at the base circular portion of said cam.
Claim 5
Dependent Claim
36 words
A method according to claim 1, wherein the width (b 2 ) of said hardened layer (9) at the surface is made larger than a contacting width (a) of a cam follower, such as a rocker-arm.
References Cited (Backward Citations)
No citation records indexed.
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