Patent US3919936A successfully refreshed from Google Patents.
US3919936A
Expired / Lapsed
US
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High speed line printing apparatus
Assignee: SILOICON VALLEY BANK
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Filing: 1974-01-23
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Granted: 1975-11-18
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Expires: 1994-01-23
Abstract
Abstract A high speed line printer includes a print-receiving medium, a continuously moving type carrier, a ribbon positioned between the print-receiving medium and the type carrier, and a bank of hammer units having individually fired but simultaneously retracted hammers positioned adjacent the print-receiving medium. Each hammer is magnetically retracted and held against the force of a flat spring armature. Upon release of a hammer, the stored mechanical energy of the spring causes the hammer to be driven to a printing impact and a damper prevents subsequent printing impacts due to hammer oscillation. Each hammer unit comprises a pole piece with a convex pole face and a hammer which includes the flat spring armature secured at one end to the pole piece and an impact element mounted on the outer surface of the armature at the other, free end thereof. The damper has a low mass body which includes energy absorbing material and is spring biased to a normal position in contact with the impact element. The utilization of multiple impacts between the damper and hammer permits the damper mass to be reduced so as to reduce the total movable mass, thereby decreasing hammer flight time and increasing efficiency. An interposer is operable to prevent the printing of an unwanted line by inhibiting the flight of the hammers in the event of an error condition such as a power failure.
Inventors
- 👤 Gordon Brent Barrus
- 👤 Leo Joseph Emenaker
- 👤 Raymond Franklin Melissa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:26
CPC Classifications
B; B41; B41J; B41J9/00; B41J9/26; B41J9/36; B41J29/00; B41J29/54; B41J29/58; B41J9/02; B41J9/10; B41J9/42
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
388 words
In a high speed line printing apparatus for printing on a print-receiving medium such as a paper form, said apparatus including a print mechanism comprising hammer means selectively operable during print cycles in timed relation with a movable character carrier to make printing impact with said paper form and means for advancing said paper form in a feed direction incrementally past said print mechanism, said hammer means having a printing impact position and a retracted position away from said printing impact position, said paper form being advanced between successive timed print cycles, the character carrier being of the type which moves transverse to the feed direction of the paper form, the combination comprising: means for tensioning and clamping the paper form including: i. a bar extending substantially the entire width of said paper form and positioned to ride in contact with said form; ii. a resilient backstop disposed opposite said bar; iii. means coupled to said bar for continuously biasing said paper form against said resilient backstop to maintain said paper form under tension during advancement thereof; and iv. means responsive to said timed print cycles for displacing said bar toward said backstop to firmly clamp said paper form between said bar and said backstop during each of said timed print cycles; said print mechanism being disposed between said advancing means and said tensioning and clamping means along the feed direction of said paper form; means for sensing at least one error condition requiring inhibition of said hammer means to prevent said hammer means from reaching said printing impact position, said sensing means producing a signal indicative of the presence of said error condition; an interposer member integral with said bar, said interposer member having an inhibiting position in which said member is disposed to engage said hammer means and prevent said hammer means from reaching said printing impact position and a noninhibiting position in which said hammer means is free to move to said printing impact position, said member being biased to said non-inhibiting position by said biasing means, the mass of said interposer and bar being substantially greater than the movable mass of said hammer means; and means coupled to said error sensing means and connected to said interposer member and bar for displacing said member to said inhibiting position in response to said error-indicating signal.
Claim 2
Dependent Claim
388 words
In a high speed line printing apparatus for printing on a print-receiving medium such as a paper form, said apparatus including a print mechanism comprising hammer means selectively operable during print cycles in timed relation with a movable character carrier to make printing impact with said paper form and means for advancing said paper form in a feed direction incrementally past said print mechanism, said hammer means having a printing impact position and a retracted position away from said printing impact position, said paper form being advanced between successive timed print cycles, the character carrier being of the type which moves transverse to the feed direction of the paper form, the combination comprising: means for tensioning and clamping the paper form including: i. a bar extending substantially the entire width of said paper form and positioned to ride in contact with said form; ii. a resilient backstop disposed opposite said bar; iii. means coupled to said bar for continuously biasing said paper form against said resilient backstop to maintain said paper form under tension during advancement thereof; and iv. means responsive to said timed print cycles for displacing said bar toward said backstop to firmly clamp said paper form between said bar and said backstop during each of said timed print cycles; said print mechanism being disposed between said advancing means and said tensioning and clamping means along the feed direction of said paper form; means for sensing at least one error condition requiring inhibition of said hammer means to prevent said hammer means from reaching said printing impact position, said sensing means producing a signal indicative of the presence of said error condition; an interposer member integral with said bar, said interposer member having an inhibiting position in which said member is disposed to engage said hammer means and prevent said hammer means from reaching said printing impact position and a noninhibiting position in which said hammer means is free to move to said printing impact position, said member being biased to said non-inhibiting position by said biasing means, the mass of said interposer and bar being substantially greater than the movable mass of said hammer means; and means coupled to said error sensing means and connected to said interposer member and bar for displacing said member to said inhibiting position in response to said error-indicating signal.
Claim 3
Dependent Claim
373 words
In a high speed line printing apparatus for printIng on a print-receiving medium such as a paper form having a given width, said apparatus including a movable character carrier, a print mechanism comprising a bank of hammer means, and means for incrementally advancing said paper form in a feed direction passing between said movable character carrier and said print mechanism, said hammer means having a printing impact position and a retracted position away from said printing impact position and being selectively operable during print cycles in timed relation with said character carrier to make printing impact with said paper form along a print line transverse to said feed direction, said paper form being advanced between successive print cycles, the combination comprising: a resilient backing member extending across the width of said paper form on the side opposite said print line and parallel thererto; an interposer and clamp assembly disposed adjacent the print line, said assembly including: e. a paper form clamp bar extending across the with of said paper form in confronting relationship with said resilient backing member; ii. an interposer plate secured to said clamp bar and having a surface extending along said bank of hammer means and immediately adjacent thereto; and iii. means for supporting said assembly for movement toward and away from said paper form, said supporting means biasing said assembly toward a first operative position in which said clamp bar is adapted to lightly press said paper form against said resilient backing member to tension said paper form during advancement thereof; means for generating a clamp signal during the portion of each print cycle that printing impact takes place; actuator means responsive to said clamp signal and connected to said assembly for moving said assembly to a second operative position in which said clamp bar firmly clamps said paper form against said resilient backing member during said portion of said print cycle; and means for generating a hammer means inhibit signal, said actuating means being coupled to said inhibit signal generating means to be responsive thereto to move said asssembly to a third operative position in which said interposer plate surface is disposed to engage said hammer means to prevent said hammer means from reaching said printing impact position.
Claim 4
Dependent Claim
373 words
In a high speed line printing apparatus for printIng on a print-receiving medium such as a paper form having a given width, said apparatus including a movable character carrier, a print mechanism comprising a bank of hammer means, and means for incrementally advancing said paper form in a feed direction passing between said movable character carrier and said print mechanism, said hammer means having a printing impact position and a retracted position away from said printing impact position and being selectively operable during print cycles in timed relation with said character carrier to make printing impact with said paper form along a print line transverse to said feed direction, said paper form being advanced between successive print cycles, the combination comprising: a resilient backing member extending across the width of said paper form on the side opposite said print line and parallel thererto; an interposer and clamp assembly disposed adjacent the print line, said assembly including: e. a paper form clamp bar extending across the with of said paper form in confronting relationship with said resilient backing member; ii. an interposer plate secured to said clamp bar and having a surface extending along said bank of hammer means and immediately adjacent thereto; and iii. means for supporting said assembly for movement toward and away from said paper form, said supporting means biasing said assembly toward a first operative position in which said clamp bar is adapted to lightly press said paper form against said resilient backing member to tension said paper form during advancement thereof; means for generating a clamp signal during the portion of each print cycle that printing impact takes place; actuator means responsive to said clamp signal and connected to said assembly for moving said assembly to a second operative position in which said clamp bar firmly clamps said paper form against said resilient backing member during said portion of said print cycle; and means for generating a hammer means inhibit signal, said actuating means being coupled to said inhibit signal generating means to be responsive thereto to move said asssembly to a third operative position in which said interposer plate surface is disposed to engage said hammer means to prevent said hammer means from reaching said printing impact position.
Claim 5
Dependent Claim
90 words
The combination, as defined in claim 2, in which said means for generating said hammer means inhibit signal includes: normally open switch means connected to said actuator means; means for sensing at least one error condition requiring inhibition of said hammer means, said sensing means being coupled to control said switching means; and energy storage means coupled to said switch means, the presence of said error condition closing said switch means to connect said energy storage means to said actuator means to move said assembly to said third operative position.
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) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |