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US4591876A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermal printer

Assignee: Canon Inc
•
Filing: 1982-09-27
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Granted: 1986-05-27
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Expires: 2002-09-27
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Abstract

Abstract A thermal transfer printer includes a thermal head having plural heat generating elements, a thermal head driver connected to a character generator for controlling the thermal head by supplying drive currents to the heat generating elements of the thermal head in response to print information, and control circuit for controlling the drive currents from the thermal head driver in response to the ambient temperature. Therefore, the thermal transfer printer is capable of constantly providing an optimum transfer density regardless of the ambient temperature, thus ensuring a satisfactory print quality.

Inventors

  • 👤 Mineo Nozaki
  • 👤 Osamu Asakura
  • 👤 Masasumi Nagashima
  • 👤 Yoshio Uchikata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 15:50
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/315; B41J2/32; B41J2/35; B41J2/355; B41J2/36; B41J2/365

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 163 words
A thermal printer comprising: a thermal head of one of at least two types having a plurality of heater elements and respective different operating characteristics, said thermal head being removably mountable to the printer; driver means operable in response to a print signal for driving said heater elements; detection means for detecting the type of said thermal head mounted to the printer; and control means for controlling the heating of a first type of said thermal head in dependence on a first ambient temperature vs. power characteristic curve when said detection means detects that said first type of thermal head is mounted to the printer and for controlling the heating of a second type of said thermal head in dependence on a second ambient temperature vs. power characteristic curve when said detection means detects that said second type of thermal head is mounted to the printer so that said first and second types of thermal head print with substantially the same print density.
Claim 2
Dependent Claim 163 words
A thermal printer comprising: a thermal head of one of at least two types having a plurality of heater elements and respective different operating characteristics, said thermal head being removably mountable to the printer; driver means operable in response to a print signal for driving said heater elements; detection means for detecting the type of said thermal head mounted to the printer; and control means for controlling the heating of a first type of said thermal head in dependence on a first ambient temperature vs. power characteristic curve when said detection means detects that said first type of thermal head is mounted to the printer and for controlling the heating of a second type of said thermal head in dependence on a second ambient temperature vs. power characteristic curve when said detection means detects that said second type of thermal head is mounted to the printer so that said first and second types of thermal head print with substantially the same print density.
Claim 3
Dependent Claim 17 words
A thermal printer according to claim 1, wherein said control means includes a plurality of temperature sensors.
Claim 4
Dependent Claim 28 words
A thermal printer according to claim 2, wherein said detection means includes switch means operable in response to the type of said thermal head mounted to the printer.
Claim 5
Dependent Claim 27 words
A thermal printer according to claim 3, wherein said control means includes means for selecting among said temperature sensors depending on the operation of said switch means.
Claim 6
Dependent Claim 24 words
A thermal printer according to claim 1, further comprising an ink ribbon having an ink layer melted by heat generated by said thermal head.
Claim 7
Dependent Claim 178 words
A thermal printer comprising: first thermal head means of a first type having a plurality of heater elements and being removably mountable to the printer; second thermal head means of a second type having a plurality of heater elements and being removably mountable to the printer; driver means operable in response to a print signal for driving said first and second thermal head means; detection means for detecting which of said first or second thermal head means is mounted to the printer; first control means for controlling the heating of said first thermal head means in dependence on a first ambient temperature vs. power characteristic curve when said detection means detects that said first thermal head means is mounted; and second control means for controlling the heating of said second thermal head means in dependence on a second ambient temperature vs. power characteristic curve when said detection means detects that said second thermal head means is mounted so that said second thermal head means can print with substantially the same print density as said first thermal head means.
Claim 8
Dependent Claim 178 words
A thermal printer comprising: first thermal head means of a first type having a plurality of heater elements and being removably mountable to the printer; second thermal head means of a second type having a plurality of heater elements and being removably mountable to the printer; driver means operable in response to a print signal for driving said first and second thermal head means; detection means for detecting which of said first or second thermal head means is mounted to the printer; first control means for controlling the heating of said first thermal head means in dependence on a first ambient temperature vs. power characteristic curve when said detection means detects that said first thermal head means is mounted; and second control means for controlling the heating of said second thermal head means in dependence on a second ambient temperature vs. power characteristic curve when said detection means detects that said second thermal head means is mounted so that said second thermal head means can print with substantially the same print density as said first thermal head means.
Claim 9
Dependent Claim 17 words
A thermal printer according to claim 6, wherein said first control means includes a first temperature sensor.
Claim 10
Dependent Claim 17 words
A thermal printer according to claim 6, wherein said second control means includes a second temperature sensor.
Claim 11
Dependent Claim 29 words
A thermal printer according to claim 6, wherein said detection means includes switching means operable in response to mounting said first and second thermal head means on the printer.
Claim 12
Dependent Claim 28 words
A thermal printer according to claim 6, further comprising an ink ribbon having an ink layer melted by heat generated by said thermal head mounted to the printer.
Claim 13
Dependent Claim 106 words
A thermal printer comprising: thermal head means for printing characters in a first character size and a second character size different from the first character size; switch means for changing between the first and second character sizes; and control means responsive to said switch means for controlling the heating of said thermal head means in dependence on a first ambient temperature vs. power characteristic curve for the first character size and in dependence on a second ambient temperature vs. power characteristic curve for the second character size so that substantially the same print density can be obtained with either of the first and second character size.
Claim 14
Dependent Claim 106 words
A thermal printer comprising: thermal head means for printing characters in a first character size and a second character size different from the first character size; switch means for changing between the first and second character sizes; and control means responsive to said switch means for controlling the heating of said thermal head means in dependence on a first ambient temperature vs. power characteristic curve for the first character size and in dependence on a second ambient temperature vs. power characteristic curve for the second character size so that substantially the same print density can be obtained with either of the first and second character size.
Claim 15
Dependent Claim 25 words
A thermal printer according to claim 11, further comprising an ink ribbon having an ink layer melted by heat generated by said thermal head means.

References Cited (Backward Citations)

DE2928304A1 Cited
US4396923A Cited
US4350448A Cited
US4370666A Cited
US4411540A Cited
US4399749A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-05-26 1989-11-25 1990-05-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-05-26 1993-11-25 1994-05-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-05-26 1997-11-25 1998-05-27 $7700.00 Window Closed / Lapsed

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