DATA ENTRY DEVICE

• US 3,815,127 A
• Filed: 03/20/1973
• Issued: 06/04/1974
• Est. Priority Date: 03/20/1973
• Status: Expired due to Term

• Current Assignee: Eugene G. Blumke, Kenneth N. Bergan
• Original Assignee: Eugene G. Blumke, Kenneth N. Bergan
• Inventors: Blumke, Eugene G., Bergan, Kenneth N.
• Primary Examiner(s): Habecker, Thomas B.
• Application Number:
  US05/343,074
• Time in Patent Office: 441 Days
• Field of Search: 340/365S,365C
• US Class Current: 341/5
• CPC Class Codes: H03K 17/98 having a plurality of control members, e.g. keyboard

Abstract

A data entry device comprises a plurality of pairs of sensors connected to a like plurality of bridge arrangements so that actuation of one of said pair of sensors unbalances the respective bridge in one state and actuation of the other of said pair of sensors unbalances the respective bridge in an opposite state. Scanner means is provided to sequentially scan the bridges to provide signals whose amplitudes are representative of the state of balance or unbalance of the respective bridges and whose phase is representative of the sense of unbalance. A level detector is provided to sense the amplitude of signals from the scanner to provide an output signal indicative of the unbalanced bridge, and a phase detector is provided to sense the phase of signals to provide an output signal representative of the state of unbalance.

Claims

1. A data entry device comprising a plurality of pairs of sensors;

input circuit means connected to each of said pairs of sensors, said input circuit means having a plurality of outputs, each output being associated with one pair of sensors, said input circuit means being responsive to the actuation of a sensor to provide a first signal at the output associated with the pair of sensors containing the actuated sensor, said first signal having a characteristic representative of the actuated one of the respective pair of sensors;

level detector means;

scanner means connected between said input circuit means and said level detector means for sequentially scanning said plurality of outputs of said input circuit means to provide said first signals to said level detector means;

said level detector means being responsive to said first signal for detecting the pair of sensors containing the actuated sensor;

output means responsive to operation of said level detector means and said scanner means for providing a first output signal representative of the pair of sensors containing the operated sensor; and

characteristic detector means responsive to the said characteristic of said first signal for providing a second output signal representative of the actuated sensor of said pair of sensors.

2. A data entry device according to claim 1 wherein said input circuit means includes a plurality electric bridge means, a first of each pair of sensors being connected to one leg of a respective bridge means and operable to unbalance the respective bridge means in a first sense and a second of each pair of sensors being connected to a second leg of the respective bridge means and operable to unbalance the respective bridge means in a second sense different from said first sense, said scanner means being operable to sequentially scan said bridge means to provide sequential first signals, said first signals having an amplitude representative of the unbalance or balance of a respective bridge means and a phase representative of the sense of unbalance.

3. A data entry device according to claim 2 further including inhibit means responsive to said level detector means for inhibiting operation of said scanner means when said level detector means detects a signal amplitude representative of an unbalanced bridge means, said scanner means including counter means providing a count signal indicative of the bridge means being scanned, said output means being responsive to said count signal and to operation of said level detector means to provide said first output signal.

4. A data entry device according to claim 2 further including signal producing means for producing signals at a predetermined frequency, bridge drive means connected to said signal producing means for supplying drivE signals having said predetermined frequency to each of said bridge means.

5. A data entry device according to claim 4 further including inhibit means responsive to said level detector means for inhibiting operation of said scanner means when said level detector means detects a signal amplitude representative of an unbalanced bridge means, said scanner means including counter means providing a count signal indicative of the bridge means being scanned, said output means being responsive to said count signal and to operation of said level detector means to provide said first output signal.

6. A data entry device according to claim 5 wherein said level detector means includes first comparator means for comparing the amplitude of said first signals to a reference signal amplitude, integrator means connected to the output of said first comparator means for integrating the signal from said first comparator, second comparator means for comparing the amplitude of signals from said integrator means to a reference signal amplitude, and first AND gate means responsive to outputs from said first and second comparator means to actuate said inhibit means.

7. A data entry device according to claim 6 wherein said characteristic detector means is a phase detector means and includes second AND gate means responsive to the output of said first comparator means and to the output of said producing means for determining the phase of said input signal.

8. A data entry device according to claim 7 wherein said phase detector means further includes second integrator means for integrating signals passed by said second AND gate means, third comparative means for passing integrated signals from said second integrator means having a predetermined amplitude, and third AND gate means operable to pass signals upon a coincidence of occurrence of signals from said third comparator means and said first AND gate means.

9. A data entry device according to claim 8 wherein said output means includes binary decoder means responsive to said count signal and to the output from said third AND gate means to provide said first output signal indicative of the actuated sensor.

10. A data entry device according to claim 1 further including inhibit means responsive to said level detector means for inhibiting operation of said scanner means when said level detector means detects a signal representative of actuation of one of a pair of sensors, said scanner means including counter means providing a count signal indicative of the input circuit means being scanned, said output means being responsive to said count signal and to operation of said level detector means to provide said first output signal.

11. A data entry device according to claim 10 wherein said level detector means includes first comparator means for comparing the amplitude of said first signals to a reference signal amplitude, integrator means connected to the output of said first comparator means for integrating the signal from said first comparator, second comparator means for comparing the amplitude of signals from said integrator means to a reference signal amplitude, and AND gate means responsive to outputs from said first and second comparator means to actuate said inhibit means.

12. A data entry device according to claim 1 wherein said characteristic detector means is a phase detector means responsive to the phase of said signals.

13. A data entry device according to claim 12 wherein said phase detector means includes first AND gate means responsive to the output of said level detector means and to output of said signal producing means for comparing the phase of said first signal.

14. A data entry device according to claim 13 wherein said phase detector means further includes integrator means for integrating signals passed by said first AND gate means, comparator means for passing integrated signals from said integrator means having a predetermined amplitude, and second AND gate means operable to pass signals upOn a coincidence of operation of said level detector means and said comparator means.

15. A data entry device according to claim 14 wherein said output means includes binary decoder means responsive to a count signal from said scanner means and to the output from said second AND gate means to provide an output signal indicative of the actuated sensor.