US4248555A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drill assembly
Assignee: Showa Machine Ind Co Ltd
•
Filing: 1979-08-09
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Granted: 1981-02-03
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Expires: 1999-08-09
Abstract
Abstract A drill assembly has two inserts clamped in the respective radial recesses formed in the body. One insert has a straight edge and the other insert has a notched edge. The arrangement is such that the notched edge of the other insert is disposed slightly above the straight edge of one insert.
Inventors
- 👤 Masanori Satou
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:55
CPC Classifications
B; B23; B23B; B23B51/00; B23B2251/00; B23B2251/48; B23B2251/60; B23B2251/603; B23B2260/00; B23B2260/088; Y; Y10; Y10T; Y10T408/00; Y10T408/86; Y10T408/89; Y10T408/905; Y10T408/906; Y10T408/9065
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
113 words
A drill assembly comprising: a body being formed in the center thereof with a center hole axially extending, with two angular cuts for chip ejection, and in the upper surface thereof with two recesses extending radially, a center drill mounted in said center hole, a first insert having a straight cutting edge, a second insert having a notched cutting edge formed with a plurality of notches, said first and second inserts being adapted to be clamped in said recesses in such positions that the notched edge of said second insert will be disposed above the straight edge of said first insert, and means for clamping said first and second inserts in said recesses.
Claim 2
Dependent Claim
113 words
A drill assembly comprising: a body being formed in the center thereof with a center hole axially extending, with two angular cuts for chip ejection, and in the upper surface thereof with two recesses extending radially, a center drill mounted in said center hole, a first insert having a straight cutting edge, a second insert having a notched cutting edge formed with a plurality of notches, said first and second inserts being adapted to be clamped in said recesses in such positions that the notched edge of said second insert will be disposed above the straight edge of said first insert, and means for clamping said first and second inserts in said recesses.
Claim 3
Dependent Claim
32 words
A drill assembly as claimed in claim 1, wherein the ratio of the notched portion of the cutting edge of said second insert to the straight portion thereof is about 50 percent.
Claim 4
Dependent Claim
18 words
A drill assembly as claimed in claim 1, wherein one of said recesses is shallower than the other.
Claim 5
Dependent Claim
20 words
A drill assembly as claimed in claim 1, wherein said second insert having a larger height than said first insert.
Claim 6
Dependent Claim
38 words
A drill assembly as claimed in claim 1, wherein said center drill has an axial groove in which the inner end of said second insert engages to prevent said center drill from turning with respect to said body.
Claim 7
Dependent Claim
28 words
A drill assembly as claimed in claim 1 further comprising a spring disposed at bottom of said center hole so that said center drill will project therefrom accordingly.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-03 | 1984-08-04 | 1985-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-03 | 1988-08-04 | 1989-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-03 | 1992-08-04 | 1993-02-03 | $7700.00 | Window Closed / Lapsed |