US3575107A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Underspeed and undervoltage protection for printer
Assignee: Genicom Corp
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Filing: 1969-06-02
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Granted: 1971-04-13
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Expires: 1989-06-02
Abstract
Abstract An underspeed and undervoltage protection system for an electromechanical printer. The printer includes a plurality of moving characters actuated by stationary print hammers. The speed of the moving characters is continuously monitored along with the input voltage to the printer system. A synchronizing signal is provided which indicates when the characters are positioned to permit application of buss voltage which is the source of energization of the print hammers. When the speed of the characters and the input voltage reach predetermined minimum values, power is applied to a power buss for energizing the print hammers, the application of power being delayed until the synchronizing signal indicates that the print hammers are not in position to be energized. Similarly, if the speed of the characters or the input voltage subsequently falls below the predetermined minimum values, the hammer power buss is synchronously deenergized so as to prevent damage to the printer mechanism.
Inventors
- 👤 Earle B Mcdowell
- 👤 Clifford M Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:49
CPC Classifications
G; G06; G06K; G06K15/00; G06K15/02; G06K15/08
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
174 words
A protection system for a printer having a plurality of movable characters and a plurality of electrically energizable hammers for engaging the characters comprising: a. indication means for indicating the speed of said characters; b. a speed reference generator for generating a speed reference signal indicative of the minimum permissible speed of said characters; c. speed detecting means operatively connected to said indication means and said speed reference generator for generating a signal when the speed of said characters is less than said speed reference; d. undervoltage detecting means for indicating when the input voltage to said printer is below a predetermined value; e. synchronizing means for generating an output signal indicating when the hammers are permitted to be energized; and f. deenergization means operatively connected to said speed detecting means, said undervoltage detecting means and said synchronizing means so as to synchronously deenergize the hammers at a time determined by the absence of an output from said synchronizing means in response to an output from said speed detecting means or said undervoltage means.
Claim 2
Dependent Claim
174 words
A protection system for a printer having a plurality of movable characters and a plurality of electrically energizable hammers for engaging the characters comprising: a. indication means for indicating the speed of said characters; b. a speed reference generator for generating a speed reference signal indicative of the minimum permissible speed of said characters; c. speed detecting means operatively connected to said indication means and said speed reference generator for generating a signal when the speed of said characters is less than said speed reference; d. undervoltage detecting means for indicating when the input voltage to said printer is below a predetermined value; e. synchronizing means for generating an output signal indicating when the hammers are permitted to be energized; and f. deenergization means operatively connected to said speed detecting means, said undervoltage detecting means and said synchronizing means so as to synchronously deenergize the hammers at a time determined by the absence of an output from said synchronizing means in response to an output from said speed detecting means or said undervoltage means.
Claim 3
Dependent Claim
30 words
The protection system recited in claim 1 further comprising a hammer power buss for selectively energizing the hammers and wherein said deenergization means operates to deenergize said hammer power buss.
Claim 4
Dependent Claim
99 words
The protection system recited in claim 1 wherein said speed detecting means comprises a bistable device operatively connected to said indication means to assume a first state upon receipt of an input from said indication means and wherein said speed reference generator comprises time delay means operatively connected to said indication means to begin a timing cycle in response to receipt of said input from said indication means, the output of said time delay means being operatively connected to said bistable device so as to change the state of said bistable device at the end of said timing cycle.
Claim 5
Dependent Claim
22 words
The protection system recited in claim 1 wherein said undervoltage detecting means comprises a Zener diode operatively connected to said input voltage.
Claim 6
Dependent Claim
42 words
The protection system recited in claim 1 further comprising a second time delay circuit connected between said input voltage and said undervoltage detecting means so as to desensitize said undervoltage detecting means from the effects of temporary variations in said input voltage.
Claim 7
Dependent Claim
21 words
The protection system recited in claim 1 wherein said synchronizing means comprises means for indicating the position of the movable characters.
Claim 8
Dependent Claim
193 words
A protection system for a printer having a plurality of characters on a moving belt and a plurality of electrically energizable hammers for mechanically engaging the characters so as to print the characters comprising: a. synchronizing means for generating a plurality of time-spaced pulses indicative of the position of the moving characters; b. speed detecting means operatively connected to saId synchronizing means for indicating when the time between said pulses is greater than a predetermined fixed time so as to generate an output signal indicating an underspeed condition; c. undervoltage detecting means for indicating when the input voltage to said printer is below a predetermined value; d. a power buss for selectively energizing said hammers; and e. hammer buss control means operatively connected to said synchronizing means, said speed detecting means and said undervoltage detecting means for energizing said power buss synchronous with said synchronizing means in the absence of outputs from said speed detecting means and said undervoltage means, said hammer buss control means being further operative to deenergize said power buss synchronous with said synchronizing means in response to an output from said speed detecting means or said undervoltage detecting means.
Claim 9
Dependent Claim
193 words
A protection system for a printer having a plurality of characters on a moving belt and a plurality of electrically energizable hammers for mechanically engaging the characters so as to print the characters comprising: a. synchronizing means for generating a plurality of time-spaced pulses indicative of the position of the moving characters; b. speed detecting means operatively connected to saId synchronizing means for indicating when the time between said pulses is greater than a predetermined fixed time so as to generate an output signal indicating an underspeed condition; c. undervoltage detecting means for indicating when the input voltage to said printer is below a predetermined value; d. a power buss for selectively energizing said hammers; and e. hammer buss control means operatively connected to said synchronizing means, said speed detecting means and said undervoltage detecting means for energizing said power buss synchronous with said synchronizing means in the absence of outputs from said speed detecting means and said undervoltage means, said hammer buss control means being further operative to deenergize said power buss synchronous with said synchronizing means in response to an output from said speed detecting means or said undervoltage detecting means.
Claim 10
Dependent Claim
27 words
The belt printer protection system recited in claim 7 wherein said synchronizing means comprises a photocell detector for sensing the position of the characters on the belt.
Claim 11
Dependent Claim
93 words
The system recited in claim 7 wherein said detecting means comprises a time delay means, a bistable element, said time delay responsive to receipt of normal voltage and normal speed conditions to produce a given time delayed signal, said element responsive to the simultaneous occurrence of a pulse from said synchronizing means and said time delay signal to set, means for removing said time delayed signal in response to an underspeed or undervoltage condition, said element responsive to removal of said time delayed signal and the absence of said synchronizing pulse to reset.
Claim 12
Dependent Claim
42 words
The belt printer control system recited in claim 7 wherein said undervoltage detecting means includes a Zener diode having a breakdown voltage corresponding to a predetermined minimum voltage and time delay means operatively connected between said input voltage and said Zener diode.
Claim 13
Independent Claim
87 words
A method of protecting a printer having a plurality of movable characters and a plurality of electrically energizable hammers for engaging the characters comprising: a. indicating the speed of the moving characters; b. comparing the indicated speed of the characters with a predetermined lower speed limit; c. comparing the input voltage to the printer with a predetermined reference; d. deenergizing the print hammers at a time when the print hammers are not permitted to be energized if either the speed or voltage is below the predetermined limits.
Claim 14
Independent Claim
87 words
A method of protecting a printer having a plurality of movable characters and a plurality of electrically energizable hammers for engaging the characters comprising: a. indicating the speed of the moving characters; b. comparing the indicated speed of the characters with a predetermined lower speed limit; c. comparing the input voltage to the printer with a predetermined reference; d. deenergizing the print hammers at a time when the print hammers are not permitted to be energized if either the speed or voltage is below the predetermined limits.
Claim 15
Dependent Claim
38 words
The method of protecting a printer recited in claim 11 wherein the step of comparing the speed of the characters comprises comparing the time spacing of pulses indicating the speed of the characters with a fixed time delay.
Claim 16
Dependent Claim
63 words
The method of protecting a printer recited in claim 11 wherein the step of deenergizing the print hammers comprising generating a signal indicating when the print hammers are permitted to be energized and then delaying the deenergization of the print hammers until the first time the generated signal is absent following an indication that the speed or voltage is below the predetermined limits.
Claim 17
Dependent Claim
84 words
A protection system for a printer having a plurality of movable characters and a plurality of recurrently, selectively electrically energizable hammers for engaging the characters comprising: a. means for providing a first signal only when the speed of said characters is different from a desired speed; b. means normally providing a second signal only when selected hammers are to be energized; and c. means responsive to said first signal and the absence of a second signal to prevent a subsequent recurrent energization of hammers.
Claim 18
Dependent Claim
84 words
A protection system for a printer having a plurality of movable characters and a plurality of recurrently, selectively electrically energizable hammers for engaging the characters comprising: a. means for providing a first signal only when the speed of said characters is different from a desired speed; b. means normally providing a second signal only when selected hammers are to be energized; and c. means responsive to said first signal and the absence of a second signal to prevent a subsequent recurrent energization of hammers.
Claim 19
Dependent Claim
111 words
A protection system for a printer having a plurality of movable characters and a plurality of recurrently, selectively, electrically energizable hammers for engaging the characters comprising: a. means for providing a first signal only when the speed of said characters is different from a desired speed; b. means for providing a second signal only when the input voltage to said printer is different from a desired value; c. means normally providing a third signal only when selected hammers are to be energized; and d. means responsive to at least one of said first and second signals and the absence of a third signal to prevent a subsequent recurrent energization of hammers.
Claim 20
Dependent Claim
111 words
A protection system for a printer having a plurality of movable characters and a plurality of recurrently, selectively, electrically energizable hammers for engaging the characters comprising: a. means for providing a first signal only when the speed of said characters is different from a desired speed; b. means for providing a second signal only when the input voltage to said printer is different from a desired value; c. means normally providing a third signal only when selected hammers are to be energized; and d. means responsive to at least one of said first and second signals and the absence of a third signal to prevent a subsequent recurrent energization of hammers.
Claim 21
Dependent Claim
121 words
A protection system for a printer having a plurality of characters on a moving belt and a plurality of recurrently, selectively electrically energizable hammers for mechanically engaging the characters so as to print the characters comprising: a. synchronizing means for generating a plurality of time-spaced pulses whose time occurrence is indicative of the position of the moving characters; b. means for providing a first signal only when the time between said pulses is different from a desired time to indicate an undesirable speed condition; c. means normally providing a second signal only when selected hammers are to be energized; d. means responsive to said first signal and the absence of a second signal to prevent a subsequent recurrent energization of hammers.
Claim 22
Dependent Claim
121 words
A protection system for a printer having a plurality of characters on a moving belt and a plurality of recurrently, selectively electrically energizable hammers for mechanically engaging the characters so as to print the characters comprising: a. synchronizing means for generating a plurality of time-spaced pulses whose time occurrence is indicative of the position of the moving characters; b. means for providing a first signal only when the time between said pulses is different from a desired time to indicate an undesirable speed condition; c. means normally providing a second signal only when selected hammers are to be energized; d. means responsive to said first signal and the absence of a second signal to prevent a subsequent recurrent energization of hammers.
Claim 23
Dependent Claim
93 words
The belt printer protection system recited in claim 16 wherein the source of said first signal comprises a bistable device operatively connected to said synchronizing means to assume a first state in response to a pulse from said synchronizing means, time delay means operatively connected to said synchronizing means to begin a timing cycle in response to a pulse from said synchronizing means, the output of said delay means being operatively connected to said bistable device so as to change the state of said bistable device at the end of said timing cycle.
Claim 24
Dependent Claim
89 words
A protection system for a printer having a plurality of movable characters and a plurality of recurrently, selectively, electrically energizable printing elements for cooperating with the characters to effect printing: a. means for providing a first signal only when the speed of said characters is different from a desired speed; b. means normally providing a second signal only when selected printing elements are to be energized; and c. means responsive to said first signal and the absence of a second signal to prevent a subsequent energization of printing elements.
Claim 25
Dependent Claim
89 words
A protection system for a printer having a plurality of movable characters and a plurality of recurrently, selectively, electrically energizable printing elements for cooperating with the characters to effect printing: a. means for providing a first signal only when the speed of said characters is different from a desired speed; b. means normally providing a second signal only when selected printing elements are to be energized; and c. means responsive to said first signal and the absence of a second signal to prevent a subsequent energization of printing elements.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-12 | 1974-10-12 | 1975-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-12 | 1978-10-12 | 1979-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-12 | 1982-10-12 | 1983-04-13 | $7700.00 | Window Closed / Lapsed |