US3628644A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically driven-type element
Assignee: International Business Machines Corp
•
Filing: 1969-12-22
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Granted: 1971-12-21
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Expires: 1989-12-22
Abstract
Abstract The impact time of an electrically driven-type element is directly sensed and employed to control a direct printer function, such as the impact drive itself or an ancillary printer function such as letter feed or data input control. Actual sensing of the impact point is preferably accomplished by observing the impact-force-induced polarity change of back EMF of a DC motor employed to drive the type element. Back EMF is also employed to control impact drive velocity.
Inventors
- 👤 Walter O Cralle Jr
- 👤 Henry W Simpson
- 👤 Barry C Kockler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:33
CPC Classifications
B; B41; B41J; B41J7/00; B41J7/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
98 words
A printer having a type-bearing member, a platen member, and means mounting one of said members for relative movement into mutual impact cooperation with the other of said members, wherein the improvement comprises: a direct-current electric motor for driving said one member into said impact cooperation with said other member, said electric motor generating back EMF, and circuit means for selectively delivering impact driving current to said electric motor and comprising means responsive to a change in polarity of said back EMF induced by said impact cooperation for reversing the direction of current delivered to said electric motor.
Claim 2
Dependent Claim
98 words
A printer having a type-bearing member, a platen member, and means mounting one of said members for relative movement into mutual impact cooperation with the other of said members, wherein the improvement comprises: a direct-current electric motor for driving said one member into said impact cooperation with said other member, said electric motor generating back EMF, and circuit means for selectively delivering impact driving current to said electric motor and comprising means responsive to a change in polarity of said back EMF induced by said impact cooperation for reversing the direction of current delivered to said electric motor.
Claim 3
Dependent Claim
98 words
A printer having a type-bearing member, a platen member, and means mounting one of said members for relative movement into mutual impact cooperation with the other of said members, wherein the improvement comprises: a direct-current electric motor for driving said one member into said impact cooperation with said other member, said electric motor generating back EMF, and circuit means for selectively delivering impact driving current to said electric motor and comprising means responsive to a change in polarity of said back EMF induced by said impact cooperation for terminating delivery of said impact driving current to said motor.
Claim 4
Dependent Claim
98 words
A printer having a type-bearing member, a platen member, and means mounting one of said members for relative movement into mutual impact cooperation with the other of said members, wherein the improvement comprises: a direct-current electric motor for driving said one member into said impact cooperation with said other member, said electric motor generating back EMF, and circuit means for selectively delivering impact driving current to said electric motor and comprising means responsive to a change in polarity of said back EMF induced by said impact cooperation for terminating delivery of said impact driving current to said motor.
Claim 5
Dependent Claim
38 words
A printer as defined in claim 2 wherein: said means for delivering current to said motor comprises control means respoNsive to back EMF produced by said motor for controlling the velocity at which said one member is driven.
Claim 6
Dependent Claim
90 words
A printer having a type-bearing member, a platen member, and means mounting one of said members for relative movement into mutual impact cooperation with the other of said members, wherein, the improvement comprises: an electric motor for driving said one member into said impact cooperation with said other member, means directly responsive to force generated by said impact cooperation for generating a control signal indicative of the instant of said impact cooperation, and printer operation control means for initiating a subsequent printer function in response to said impact-instant-indicative control signal.
Claim 7
Dependent Claim
90 words
A printer having a type-bearing member, a platen member, and means mounting one of said members for relative movement into mutual impact cooperation with the other of said members, wherein, the improvement comprises: an electric motor for driving said one member into said impact cooperation with said other member, means directly responsive to force generated by said impact cooperation for generating a control signal indicative of the instant of said impact cooperation, and printer operation control means for initiating a subsequent printer function in response to said impact-instant-indicative control signal.
Claim 8
Dependent Claim
25 words
A printer as defined in claim 4 wherein said printer operation control means comprises means for reversing the direction of current delivered to said motor.
Claim 9
Dependent Claim
42 words
A printer as defined in claim 4 wherein said force responsive means comprises electronic circuit means for sensing a change in back EMF produced by said electric motor and electronically emitting said control signal upon occurrence of said change in back EMF.
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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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |