US3872738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Machine tool
Assignee: Landis Tool Co
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Filing: 1973-09-24
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Granted: 1975-03-25
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Expires: 1993-09-24
Abstract
Abstract A machine tool comprising a machine element including a feed screw, means for displacing the machine element including a first stepping motor including a drive shaft, a second stepping motor including a drive shaft, means for interconnecting the drive shafts and the feed screw having means for rotating the feed screw in a first direction at a rate directly related to the combined rates of rotation of the drive shafts when the drive shafts rotate in a first direction, and means for rotating the feed screw in the first direction at a rate directly related to the difference between the rates of rotation of the drive shafts when one of the drive shafts is rotated in the first direction at a first rate and the second of the drive shafts is rotated in a second reverse direction at a second rate less than the first rate, means for selectively rotating the first and second stepping motors in the first direction to advance the machine element at a first rate, and means for selectively rotating the first stepping motor in the first direction at the first rate and for selectively rotating the second stepping motor in the second direction at the second rate to advance the machine element at a second slower feed rate.
Inventors
- 👤 Ralph E Price
- 👤 Robert E Bricker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:22
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/23; G05B19/238; B; B23; B23Q; B23Q5/00; B23Q5/22; B23Q5/34; B23Q5/38; B23Q5/46; B23Q5/48; B23Q5/50; F; F16; F16H; F16H37/00; F16H2700/00; F16H2700/02; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18568; Y10T74/18576; Y10T74/18624; Y10T74/19; Y10T74/19535
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
227 words
A machine tool comprising a machine element including a feed screw, means for displacing said machine element including first stepping motor means including a drive shaft, second stepping motor means including a drive shaft, means for interconnecting said drive shafts and said feed screw having means for rotating said feed screw in a first direction at a rate directly related to the combined rates of rotation of said drive shafts when said drive shafts rotate in a first direction, and means for rotating said feed screw in said first direction at a rate directly related to the difference between the rates of rotation of said drive shafts when one of said drive shafts is rotated in said first direction at a first rate and the second of said drive shafts is rotated in a second reverse direction at a second rate less than said first rate, means for selectively and conjointly rotating said first and second stepping motor means in said first direction to advance said machine element at a first speed, and means for selectively rotating said first stepping motor means in said first direction at said first rate and for selectively rotating said second stepping motor means in said second direction at said second rate, said first and second rates being selected so that said machine element will be advanced at a second slower speed.
Claim 2
Dependent Claim
227 words
A machine tool comprising a machine element including a feed screw, means for displacing said machine element including first stepping motor means including a drive shaft, second stepping motor means including a drive shaft, means for interconnecting said drive shafts and said feed screw having means for rotating said feed screw in a first direction at a rate directly related to the combined rates of rotation of said drive shafts when said drive shafts rotate in a first direction, and means for rotating said feed screw in said first direction at a rate directly related to the difference between the rates of rotation of said drive shafts when one of said drive shafts is rotated in said first direction at a first rate and the second of said drive shafts is rotated in a second reverse direction at a second rate less than said first rate, means for selectively and conjointly rotating said first and second stepping motor means in said first direction to advance said machine element at a first speed, and means for selectively rotating said first stepping motor means in said first direction at said first rate and for selectively rotating said second stepping motor means in said second direction at said second rate, said first and second rates being selected so that said machine element will be advanced at a second slower speed.
Claim 3
Dependent Claim
203 words
A machine tool according to claim 1, wherein said interconnecting means further includes means for rotating said feed screw in a second direction at a rate directly related to the combined rates of rotation of said drive shafts when said drive shafts rotate in said second direction, and means for rotating said feed screw in said second direction at a rate directly related to the difference between the rates of rotation of said drive shafts when one of said drive shafts is rotated in said second direction at a third rate and the other one of said drive shafts is rotated in said first direction at a fourth raTe less than said third rate, further comprising means for selectively and conjointly rotating said first and second stepping motor means in said second direction to retract said machine element at a third speed, and means for selectively rotating said one stepping motor means in said second direction at said third rate and for selectively rotating said other stepping motor means in said first direction at said fourth rate, said third and fourth rates being selected so that said machine element will be retracted at a fourth speed which is less than said third speed.
Claim 4
Dependent Claim
23 words
A machine tool according to claim 2 wherein said first speed equals said third speed and said second speed equals said fourth speed.
References Cited (Backward Citations)
US3241389A
Cited
US3731547A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |