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US4139313A Expired / Lapsed US ⏱️ 0.0 years remaining

Writing element for use in ball point pen

Assignee: Sailor Pen Co Ltd
•
Filing: 1976-12-03
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Granted: 1979-02-13
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Expires: 1996-12-03
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Abstract

Abstract Disclosed is a writing element for use in a ball point pen comprising a ball seat member which supports a ball on a ball seat disposed at its tip end and an outer sleeve which is fitted over the ball seat member to keep the ball on the ball seat. Said outer sleeve is slidably fitted to the ball seat member so as to be frictionally engaged with the ball seat member to be slid rearwardly by the extent to which the ball seat has been worn due to the writing pressure acting on the sleeve.

Inventors

  • 👤 Jiro Hori

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 14:50
CPC Classifications
B; B43; B43K; B43K7/00; B43K7/10; B43K7/105; B43K7/01

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 100 words
A writing element for use in a ball point pen having a body member comprising a ball seat member fixed relative to said body member and having a ball seat on its tip-end, a ball rotatably supported on the ball seat, and an outer sleeve means surrounding said ball and having holding means keeping the ball on the ball seat of the ball seat member, the outer sleeve means being frictionally slidable relative to said body member so that writing pressure enables the outer sleeve means to move backward by the extent to which the ball seat has been abraded.
Claim 2
Dependent Claim 100 words
A writing element for use in a ball point pen having a body member comprising a ball seat member fixed relative to said body member and having a ball seat on its tip-end, a ball rotatably supported on the ball seat, and an outer sleeve means surrounding said ball and having holding means keeping the ball on the ball seat of the ball seat member, the outer sleeve means being frictionally slidable relative to said body member so that writing pressure enables the outer sleeve means to move backward by the extent to which the ball seat has been abraded.
Claim 3
Dependent Claim 29 words
A writing element according to claim 1, wherein at least one part of said ball seat member has a cross section inscribed to that of said outer sleeve means.
Claim 4
Dependent Claim 33 words
A writing element according to claim 2, wherein said one part of said ball seat member has a substantially polygonal cross section and said outer sleeve means has a substantially circular cross section.
Claim 5
Dependent Claim 29 words
A writing element according to claim 2, wherein said ball seat member has a substantially elliptical cross section and said outer sleeve means has a substantially circular cross section.
Claim 6
Dependent Claim 17 words
A writing element according to claim 2, wherein said ball seat member is made of elastic material.
Claim 7
Dependent Claim 27 words
A writing element according to claim 1, wherein at least one part of said outer sleeve means has a cross section circumscribed to the ball seat member.
Claim 8
Dependent Claim 33 words
A writing element according to claim 6, wherein said one part of the outer sleeve means has a substantially polygonal cross section and the ball seat member has a substantially circular cross section.
Claim 9
Dependent Claim 41 words
A writing element according to claim 7, wherein said one part of the outer sleeve means has a smaller cross section than that of the ball and is located at a position spaced by a specified distance rearwardly from the ball.
Claim 10
Dependent Claim 46 words
A writing element according to claim 1, which further comprises a holding casing slidably fitted over the outer circumference of the outer sleeve means and fixed to the ball seat member at a specified distance taken rearwardly from the rear end of the outer sleeve means.
Claim 11
Dependent Claim 22 words
A writing element according to claim 1, wherein the outer sleeve means has a capillary groove for inducting ink to the ball.
Claim 12
Dependent Claim 22 words
A writing element according to claim 1, wherein the ball seat member has a capillary groove for inducting ink to the ball.
Claim 13
Dependent Claim 20 words
A writing element according to claim 1, which further comprises an ink feed provided integrally with the ball seat member.

References Cited (Backward Citations)

FR1002407A Cited
CH340427A Cited
GB1134034A Cited
US3945735A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-02-12 1982-08-14 1983-02-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-02-12 1986-08-14 1987-02-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-02-12 1990-08-14 1991-02-13 $7700.00 Window Closed / Lapsed

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