Patent US4817628A successfully refreshed from Google Patents.
Patent US4011071A successfully refreshed from Google Patents.
US4011071A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making glass shaving instrument
Assignee: American Optical Corp
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Filing: 1975-07-10
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Granted: 1977-03-08
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Expires: 1995-07-10
Abstract
Abstract A glass blade is produced from a preform of insoluble glass having a sharp edge encased in soluble glass. The encased preform is heated and drawn to the reduced cross-sectional size desired of the glass blade, cut transversely to length and leached for removal of the soluble glass and exposure of its sharp edge.
Inventors
- 👤 Walter P. Siegmund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:51
CPC Classifications
C; C03; C03B; C03B23/00; C03B23/02; C03B23/037; B; B26; B26B; B26B21/00; B26B21/54; B26B21/58; C03B23/04; C03B23/047; C03B23/20; C03B23/203; Y; Y10; Y10S; Y10S76/00; Y10S76/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
254 words
The method of making a cutting instrument of glass having at least one sharp edge comprising the steps of: grinding and polishing a first flat surface on a slab of soluble glass; grinding and polishing a second flat surface on a slab of insoluble glass; assembling said slabs with one of said first and second flat surfaces placed against the other; heating the assembly of said slabs to a temperature sufficient to interfacially fuse said first and second surfaces together; cutting from said assembly at an acute angle across the fused interface of said first and second surfaces a preform, the plane of one side of said preform intersecting said second flat surface of said interface at an acute angle and producing a sharp edge therealong; grinding and polishing said plane of one side of said preform to an optical flat to render said edge of maximum acuteness; fusing a second slab of soluble glass to said ground and polished side of said preform to protectively encase said acute edge of said preform; heating and drawing at least a portion of the fused unit of said preform and second slab of soluble glass in a direction substantially parallel to the direction of extension of said encased edge thereof and into a section of reduced cross-sectional size; removing said section; leaching away from said section all remaining soluble glass; and at any preselected stage of the method following said step of heating and drawing, cutting said section transaxially to a length desired of said instrument.
Claim 2
Independent Claim
254 words
The method of making a cutting instrument of glass having at least one sharp edge comprising the steps of: grinding and polishing a first flat surface on a slab of soluble glass; grinding and polishing a second flat surface on a slab of insoluble glass; assembling said slabs with one of said first and second flat surfaces placed against the other; heating the assembly of said slabs to a temperature sufficient to interfacially fuse said first and second surfaces together; cutting from said assembly at an acute angle across the fused interface of said first and second surfaces a preform, the plane of one side of said preform intersecting said second flat surface of said interface at an acute angle and producing a sharp edge therealong; grinding and polishing said plane of one side of said preform to an optical flat to render said edge of maximum acuteness; fusing a second slab of soluble glass to said ground and polished side of said preform to protectively encase said acute edge of said preform; heating and drawing at least a portion of the fused unit of said preform and second slab of soluble glass in a direction substantially parallel to the direction of extension of said encased edge thereof and into a section of reduced cross-sectional size; removing said section; leaching away from said section all remaining soluble glass; and at any preselected stage of the method following said step of heating and drawing, cutting said section transaxially to a length desired of said instrument.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-07 | 1980-09-06 | 1981-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-07 | 1984-09-06 | 1985-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-07 | 1988-09-06 | 1989-03-08 | $7700.00 | Window Closed / Lapsed |