US4488159A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pen switching mechanism in drum plotters
Assignee: Alps Alpine Co Ltd
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Filing: 1983-04-29
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Granted: 1984-12-11
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Expires: 2003-04-29
Abstract
Abstract A drum plotter has a pen carriage movable back and forth across a sheet of print paper on a platen which is rotatable about its own axis in opposite directions. The pen carriage supports thereon a pen holder unit rotatable for bringing one of pens with differently colored inks into a writing position. The pen in the writing position is pushed by a hammer toward the platen for writing desired characters, figures or the like on the sheet of print paper. The pen holder unit is rotatably actuatable by a ratchet wheel engaged by a pawl member driven intermittently by a cam mounted on a shaft supporting the pen carriage and drivable by a solenoid-operated mechanism.
Inventors
- 👤 Mitsugu Fujiwara
- 👤 Tomio Aso
- 👤 Koshiro Kurokawa
- 👤 Hideo Obara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:29
CPC Classifications
G; G01; G01D; G01D15/00; G01D15/16; B; B41; B41J; B41J2/00; B41J2/485; B41J2/49
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
182 words
A pen switching mechanism in a drum printer, comprising: (a) a platen rotatable about its own axis in one and opposite directions; (b) a shaft extending parallel to said platen; (c) a pen carriage movably mounted on said shaft in confronting relation to said platen, said pen carriage being movable along said shaft in axial directions of said platen; (d) a pen holder unit mounted on said pen carriage and supporting a plurality of pens for rotatable movement to bring one of said pens at a time into a writing position; (e) a hammer operatively mounted on said pen carriage for selectively pressing the pen in said writing position toward said platen; (f) a ratchet wheel rotatably mounted on said pen carriage for rotation with said pen holder; (g) a pawl member movably mounted on said pen carriage and operatively engaging teeth of said ratchet wheel for rotating the latter; and (h) a mechanism coupled with said shaft for angularly moving the latter about its own axis, and having a cam held in engagement with said pawl member for actuating the latter.
Claim 2
Dependent Claim
182 words
A pen switching mechanism in a drum printer, comprising: (a) a platen rotatable about its own axis in one and opposite directions; (b) a shaft extending parallel to said platen; (c) a pen carriage movably mounted on said shaft in confronting relation to said platen, said pen carriage being movable along said shaft in axial directions of said platen; (d) a pen holder unit mounted on said pen carriage and supporting a plurality of pens for rotatable movement to bring one of said pens at a time into a writing position; (e) a hammer operatively mounted on said pen carriage for selectively pressing the pen in said writing position toward said platen; (f) a ratchet wheel rotatably mounted on said pen carriage for rotation with said pen holder; (g) a pawl member movably mounted on said pen carriage and operatively engaging teeth of said ratchet wheel for rotating the latter; and (h) a mechanism coupled with said shaft for angularly moving the latter about its own axis, and having a cam held in engagement with said pawl member for actuating the latter.
Claim 3
Dependent Claim
26 words
A pen switching mechanism according to claim 1, including means on said pen carriage for driving said hammer to press the pen in said writing position.
Claim 4
Dependent Claim
15 words
A pen switching mechanism according to claim 2, wherein said means comprises a solenoid-operated mechanism.
Claim 5
Dependent Claim
21 words
A pen switching mechanism according to claim 1, wherein said pens have tip ends tilted downwardly for abutment against said platen.
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) | 1987-12-11 | 1988-06-11 | 1988-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-11 | 1992-06-11 | 1992-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-11 | 1996-06-11 | 1996-12-11 | $7700.00 | Window Closed / Lapsed |