Patent US4347786A successfully refreshed from Google Patents.
US4347786A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impact printer hammer flight time and velocity sensing means
Assignee: International Business Machines Corp
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Filing: 1979-10-01
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Granted: 1982-09-07
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Expires: 1999-10-01
Abstract
Abstract In an impact printer including a print wheel having a plurality of selectable character type bearing elements for respectively printing a plurality of characters, said print wheel being rotatable for selectively positioning selected type elements in successive print positions, impact means impellable against the selected elements to drive said elements against the printing medium and means for impelling the impact means against said selected type element, the present invention provides the improvement comprising means for sensing the flight time of the impelled impact means until impact by sensing variations in velocity of said impact means and means responsive to said sensed flight time for controlling the impelling means to vary the flight time. In accordance with another aspect of the present apparatus, means are provided for detecting the coincident engagement of the impact means with a type element by also sensing the velocity of the impact means after the impact means has reached a predetermined coincident engagement position.
Inventors
- 👤 Robert H. Sweat, Jr.
- 👤 William J. Thornhill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:49
CPC Classifications
B; B41; B41J; B41J1/00; B41J1/22; B41J1/24; B41J9/00; B41J9/44; B41J9/46; B41J9/48
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
102 words
In an impact printer including a print wheel having a plurality of selectable character type bearing elements for respectively printing a plurality of characters, said print wheel being rotatable for selectively positioning selected type elements at successive print positions, impact means impellable against said selected elements to drive said elements against a printing medium and means for impelling said impact means against said selected type element, the improvement comprising: means for detecting the coincident engagement of said impact means with a type element by sensing the velocity of said impact means after said impact means has reached a predetermined coincident engagement position.
Claim 2
Dependent Claim
102 words
In an impact printer including a print wheel having a plurality of selectable character type bearing elements for respectively printing a plurality of characters, said print wheel being rotatable for selectively positioning selected type elements at successive print positions, impact means impellable against said selected elements to drive said elements against a printing medium and means for impelling said impact means against said selected type element, the improvement comprising: means for detecting the coincident engagement of said impact means with a type element by sensing the velocity of said impact means after said impact means has reached a predetermined coincident engagement position.
Claim 3
Dependent Claim
15 words
The impact printer of claim 1 wherein said impact means comprises a print hammer missile.
Claim 4
Dependent Claim
46 words
The impact printer of claim 2 wherein each of said type elements includes a member adapted to receive and center said missile with respect to the type element and said missile includes a member adapted to register with said receiving member to effect said coincident engagement.
Claim 5
Dependent Claim
16 words
The impact printer of claim 3 wherein said registered members comprise a registered projection and notch.
Claim 6
Dependent Claim
21 words
The impact printer of claim 3 wherein said sensing means comprises magnetic transducer means positioned along the path of said missile.
Claim 7
Dependent Claim
26 words
The impact printer of claims 1 or 3 further including means for preventing further rotation of said print wheel upon a detected failure in coincident engagement.
Claim 8
Dependent Claim
62 words
The impact printer of claim 1 wherein said means for sensing the velocity of said impact means also senses velocity changes in said impact means, and further including means responsive to said sensed velocity changes for determining the flight time of said impelled impact means, and means responsive to said flight time determination for controlling impelling means to vary said flight time.
Claim 9
Dependent Claim
15 words
The impact printer of claim 7 wherein said impact means comprises a print hammer missile.
Claim 10
Dependent Claim
47 words
The impact printer of claim 8 wherein each of said type elements include a member adapted to receive and center said missile with respect to the type element and said missile further includes a member adapted to register with said receiving member to effect said coincident engagement.
Claim 11
Dependent Claim
21 words
The impact printer of claim 9 wherein said sensing means comprises magnetic transducer means positioned along the path of said missile.
References Cited (Backward Citations)
US3490010A
Cited
US3574326A
Cited
US3740615A
Cited
US3858509A
Cited
US3840105A
Cited
FR2244627A1
Cited
US3988664A
Cited
US4173927A
Cited
US4147438A
Cited
US4035781A
Cited
US4103766A
Cited
US4103617A
Cited
US4192230A
Cited
GB2008285B
Cited
US4189246A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-06 | 1986-03-08 | 1986-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-06 | 1990-03-08 | 1990-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-06 | 1994-03-08 | 1994-09-07 | $7700.00 | Window Closed / Lapsed |