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US4730581A Expired / Lapsed US ⏱️ 0.0 years remaining

Hollow cam shaft

Assignee: Nippon Piston Ring Co Ltd
•
Filing: 1986-06-04
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Granted: 1988-03-15
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Expires: 2006-06-04
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Abstract

Abstract A hollow cam shaft for use in an internal combustion engine is disclosed. The cam shaft includes a steel pipe, a journal portion and a cam portion. The journal portion is provided at a part of the outer peripheral surface of the steel pipe and having an outer diameter smaller than that of the steel pipe. A cam lobe is assembled on the other portion of the outer peripheral surface of the steel pipe. The journal portion is formed by cutting the part of the outer peripheral surface of the steel pipe by a uniform axial length and radial depth.

Inventors

  • 👤 Yoshiaki Fujita
  • 👤 Tatsumi Yunokawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:05
CPC Classifications
F; F16; F16H; F16H53/00; F16H53/02; F16H53/025; F01; F01L; F01L1/00; F01L1/02; F01L1/04; F01L1/047; F01L2001/0475

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 92 words
A hollow cam shaft comprising: a steel pipe having an outer peripheral surface, defining an outer diameter of said steel pipe, a journal portion formed by cutting a portion of said outer peripheral surface, said journal portion having a uniform axial length and uniform radial depth and having an outer diameter smaller than said outer diameter of the steel pipe, an annular groove formed at each axial end of said journal portion, a cam portion assembled to a portion of said outer peripheral surface of the steel pipe adjacent said journal portion.
Claim 2
Dependent Claim 92 words
A hollow cam shaft comprising: a steel pipe having an outer peripheral surface, defining an outer diameter of said steel pipe, a journal portion formed by cutting a portion of said outer peripheral surface, said journal portion having a uniform axial length and uniform radial depth and having an outer diameter smaller than said outer diameter of the steel pipe, an annular groove formed at each axial end of said journal portion, a cam portion assembled to a portion of said outer peripheral surface of the steel pipe adjacent said journal portion.
Claim 3
Dependent Claim 13 words
The hollow cam shaft of claim 1, wherein said journal portion is carburized.
Claim 4
Dependent Claim 13 words
The hollow cam shaft of claim 1, wherein said journal portion is quenched.
Claim 5
Dependent Claim 17 words
The hollow cam shaft of claim 1, wherein said cam portion is formed of a sintered alloy.
Claim 6
Dependent Claim 72 words
The hollow cam shaft of claim 1, wherein said steel pipe includes at least one axial groove having a radial depth, and wherein said cam portion includes a bore having an internal axial projection extending radially inward from said bore for engaging said axial groove during assembly of said cam portion with said steel pipe, the radial depth of said journal portion being greater than the radial depth of said axial groove.

References Cited (Backward Citations)

DE153622C Cited
US2397511A Cited
US3477417A Cited
US4265388A Cited
GB2050207A Cited
US4395980A Cited
EP0119112A1 Cited
GB2152858A Cited
EP0170378A1 Cited
US4592314A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-03-15 1991-09-14 1992-03-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-03-15 1995-09-14 1996-03-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-03-15 1999-09-14 2000-03-15 $7700.00 Window Closed / Lapsed

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