Patent US4074950A successfully refreshed from Google Patents.
US4074950A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Locking thread forming tap
Assignee: Individual
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Filing: 1976-10-04
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Granted: 1978-02-21
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Expires: 1996-10-04
Abstract
Abstract A thread forming tap comprising a shank section, a body section extending longitudinally from the shank section, a helical thread formed on the body section and having radially outwardly converging flank portions which define an inclined ramp arranged at a preselected angle to the axis of the tap and adapted to form a complementary inclined locking ramp on the thread to be formed by the tap.
Inventors
- 👤 Horace D. Holmes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:29
CPC Classifications
B; B23; B23G; B23G5/00; B23G5/02; B23G5/06; Y; Y10; Y10T; Y10T408/00; Y10T408/89; Y10T408/904; Y10T408/9046; Y10T408/90467
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
127 words
In a thread forming tap, a shank section, a body section extending longitudinally from the shank section having axially disposed grooves therein, a helical thread on the body section having dissimilar angularly disposed flanks extending from a pilot portion to a final thread-cutting portion representing the final configuration of the thread to be formed by said tap, one said flank in said final thread cutting portion lying at an angle relative to the longitudinal axis of the tap which is substantially greater than 35°, the opposing flank facing the shank section in said final thread-cutting portion forming a ramp of substantially less slope than that of said first flank and being arranged at an angle of approximately 25° - 35° relative to the axis of said tap.
Claim 2
Dependent Claim
127 words
In a thread forming tap, a shank section, a body section extending longitudinally from the shank section having axially disposed grooves therein, a helical thread on the body section having dissimilar angularly disposed flanks extending from a pilot portion to a final thread-cutting portion representing the final configuration of the thread to be formed by said tap, one said flank in said final thread cutting portion lying at an angle relative to the longitudinal axis of the tap which is substantially greater than 35°, the opposing flank facing the shank section in said final thread-cutting portion forming a ramp of substantially less slope than that of said first flank and being arranged at an angle of approximately 25° - 35° relative to the axis of said tap.
Claim 3
Dependent Claim
17 words
The invention as set forth in claim 1, wherein the slope of said ramp is approximately 30°.
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) | 1981-02-20 | 1981-08-22 | 1982-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-20 | 1985-08-22 | 1986-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-20 | 1989-08-22 | 1990-02-21 | $7700.00 | Window Closed / Lapsed |