Patent US4775945A successfully refreshed from Google Patents.
US4775945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Print head motor control system with automatic drive parameter calculations
Assignee: International Business Machines Corp
•
Filing: 1985-12-11
•
Granted: 1988-10-04
•
Expires: 2005-12-11
Abstract
Abstract A print head motor control system for a printer having a bidirectionally movable print head employs a microcomputer to automatically calculate print head motor parameters which are utilized to generate a motor drive voltage value for any desired print head speed. Upon powering-up of the printer, the print head is driven until contact with the left sideframe is made. A full pass from left to right is then made checking for obstructions. The print head motor is driven at a first default drive voltage value, which is assumed to drive the print head at a first preselected velocity while the first actual print head velocity is measured. The printhead motor is then driven at a second default drive voltage value, which is assumed to drive the print head at a second preselected velocity while the second actual print head velocity is measured. The first default value, first actual print head velocity, second default value and second actual print head velocity are then used to derive a voltage vs. velocity constant and a frictional value which are used to calculate the appropriate drive voltage value for any given desired print head velocity.
Inventors
- 👤 Barry R. Cavill
- 👤 Raymond A. Schulz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:14
CPC Classifications
B; B41; B41J; B41J19/00; B41J19/18; B41J19/20; B41J19/202; G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/23; G05B19/231; G05B19/232; G05B2219/00; G05B2219/30; G05B2219/42; G05B2219/42155; G05B2219/42237
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
126 words
A method of determining print head motor parameters in a print head motor control system for a printer having a bidirectionally movable print head comprising the steps of: driving said print head motor at a first preselected drive value; measuring the velocity of the print head as driven by said first preselected drive value; driving said print head motor at a second preselected drive value; measuring the velocity of the print head as driven by said second preselected drive value; determining a drive value vs. velocity constant according to the relationship of said print head velocities to said first and second preselected drive values; subsequently selecting drive values for printer operation according to said constant; and applying drive values so selected to said print head motor.
Claim 2
Independent Claim
126 words
A method of determining print head motor parameters in a print head motor control system for a printer having a bidirectionally movable print head comprising the steps of: driving said print head motor at a first preselected drive value; measuring the velocity of the print head as driven by said first preselected drive value; driving said print head motor at a second preselected drive value; measuring the velocity of the print head as driven by said second preselected drive value; determining a drive value vs. velocity constant according to the relationship of said print head velocities to said first and second preselected drive values; subsequently selecting drive values for printer operation according to said constant; and applying drive values so selected to said print head motor.
Claim 3
Dependent Claim
79 words
The method according to claim 1, wherein said step of determining a drive value vs. velocity constant includes: calculating said drive value vs. velocity constant (K) utilizing the equation ##EQU5## where V 1 =said first preselected drive value; V 2 =said second preselected drive value; Vel 1 =said measured velocity of the print head as driven by said first preselected drive value; and Vel 2 =said measured velocity of the printhead as driven by said second preselected drive value.
Claim 4
Dependent Claim
18 words
The method according to claim 1, further comprising the steps of: determining a frictional value for said motor.
Claim 5
Dependent Claim
56 words
The method according to claim 2, wherein said step of determining a drive value for a desired print head velocity includes: calculating said drive value for a desired print head velocity utilizing the equation V.sub.d =(K×VEL.sub.d)+V.sub.f where V d =drive value; K=said drive value vs. velocity constant; VEL d =said desired velocity V f =frictional value.
Claim 6
Dependent Claim
79 words
The method according to claim 3, wherein said step of determining a drive value vs. velocity constant includes: calculating said drive value vs. velocity constant (K) utilizing the equation ##EQU6## where V 1 =said first preselected drive value; V 2 =said second preselected drive value; Vel 1 =said measured velocity of the print head as driven by said first preselected drive value; and Vel 2 =said measured velocity of the printhead as driven by said second preselected drive value.
Claim 7
Dependent Claim
57 words
The method according to claim 4, wherein said step of determining a drive value for a desired print head velocity includes: calculating said drive value for a desired print head velocity utilizing the equation V.sub.d =(K×VEL.sub.d)+V.sub.f where V d =drive value; K=said drive value vs. velocity constant; VEL d =said desired velocity V f =said frictional value.
Claim 8
Dependent Claim
81 words
The method according to claim 5, wherein said step of determining said frictional value (V f ) includes: calculating said frictional value (V f ) utilizing the equation V.sub.f =V.sub.N -(K×A.sub.N) where V N =any preselected drive value which falls on the line defined by the points (Vel 1 ,V 1 ) and (Vel 2 ,V 2 ); K=said drive value vs. velocity-constant; and A N =the assumed print head velocity when driven with said preselected drive value V N .
Claim 9
Dependent Claim
57 words
The method according to claim 7, wherein said step of determining a drive value for a desired print head velocity includes: calculating said drive value for a desired print head velocity utilizing the equation V.sub.d =(K×VEL.sub.d)+V.sub.f where V d =drive value; K=said drive value vs. velocity constant; VEL d =said desired velocity V f =said frictional value.
Claim 10
Dependent Claim
204 words
A print head motor control system for bidirectionally moving said print head across a record medium, comprising: motor means having a rotatable shaft, coupled to said print head, for moving said print head as said shaft rotates; means for generating measured print head velocity information; processor means, connected to said means for generating measured print head velocity information, for generating a motor drive voltage control signal and determining desired print head velocity information; control circuit means, connected to said processor means and said motor means, for applying a motor drive voltage to said motor means, said motor drive voltage being controlled by the drive value of said motor drive voltage control signal, whereby the velocity of said print head is controlled; said processor including means for determining said measured print head velocity when said motor drive voltage is controlled by a first preselected drive value, determining said measured print head velocity when said motor drive voltage is controlled by a second preselected drive value and deriving a drive value vs. velocity constant according to said velocity values and said measured velocities; said processor means further including selection means for subsequently selecting drive values of the motor drive voltage control signal respective of said constant.
Claim 11
Dependent Claim
204 words
A print head motor control system for bidirectionally moving said print head across a record medium, comprising: motor means having a rotatable shaft, coupled to said print head, for moving said print head as said shaft rotates; means for generating measured print head velocity information; processor means, connected to said means for generating measured print head velocity information, for generating a motor drive voltage control signal and determining desired print head velocity information; control circuit means, connected to said processor means and said motor means, for applying a motor drive voltage to said motor means, said motor drive voltage being controlled by the drive value of said motor drive voltage control signal, whereby the velocity of said print head is controlled; said processor including means for determining said measured print head velocity when said motor drive voltage is controlled by a first preselected drive value, determining said measured print head velocity when said motor drive voltage is controlled by a second preselected drive value and deriving a drive value vs. velocity constant according to said velocity values and said measured velocities; said processor means further including selection means for subsequently selecting drive values of the motor drive voltage control signal respective of said constant.
Claim 12
Dependent Claim
72 words
The system, according to claim 9, wherein: said processor means determines said drive value vs. velocity constant (K) utilizing the equation ##EQU7## where V 1 =said first preselected drive value; V 2 =said second preselected drive value; Vel 1 =said measured velocity of the print head as driven by said first preselected drive value; and Vel 2 =said measured velocity of the print head as driven by said second preselected drive value.
Claim 13
Dependent Claim
46 words
The system, according to claim 10, wherein: said processor means determines said drive value for said desired print head velocity utilizing the equation V.sub.d =(K×VEL.sub.d)+V.sub.f where V d =drive value; K=said drive value vs. velocity constant; VEL d =said desired velocity V f =said frictional value.
Claim 14
Dependent Claim
35 words
The system according to claim 9, wherein: said processor means includes means for determining a frictional value for said motor and said selection means selects drive values respective of said constant and said frictional value.
Claim 15
Dependent Claim
46 words
The system, according to claim 12, wherein: said processor means determines said drive value for said desired print head velocity utilizing the equation V.sub.d =(K×VEL.sub.d)+V.sub.f where V d =drive value; K=said drive value vs. velocity constant; VEL d =said desired velocity V f =said frictional value.
Claim 16
Dependent Claim
72 words
The system according to claim 12, wherein: said processor means determines said drive value vs. velocity constant (K) utilizing the equation ##EQU8## where V 1 =said first preselected drive value; V 2 =said second preselected drive value; Vel 1 =said measured velocity of the print head as driven by said first preselected drive value; and Vel 2 =said measured velocity of the print head as driven by said second preselected drive value.
Claim 17
Dependent Claim
73 words
The system, according to claim 14, wherein: said processor means determines said frictional value (V f ) utilizing the equation V.sub.f =V.sub.N =(K×A.sub.N) where V N =any preselected drive value which falls on the line defined by the points (Vel 1 ,V 1 ) and (Vel 2 ,V 2 ); K=said drive value vs. velocity-constant; and A N =the assumed print head velocity when driven with said preselected drive value V N .
Claim 18
Dependent Claim
46 words
The system, according to claim 14, wherein: said processor means determines said drive value for said desired print head velocity utilizing the equation V.sub.d =(K×VEL.sub.d)+V.sub.f where V d =drive value; K=said drive value vs. velocity constant; VEL d =said desired velocity V f =said frictional value.
References Cited (Backward Citations)
US4287461A
Cited
US4554497A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-04 | 1992-04-04 | 1992-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-04 | 1996-04-04 | 1996-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-04 | 2000-04-04 | 2000-10-04 | $7700.00 | Window Closed / Lapsed |