Motor driving system and circuit therefor

• US 4,031,448 A
• Filed: 02/11/1976
• Issued: 06/21/1977
• Est. Priority Date: 09/26/1975
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Adachi, Yoshio
• Primary Examiner(s): Dobeck, B.
• Application Number:
  US05/657,235
• Time in Patent Office: 496 Days
• Field of Search: 318/696, 318/685, 318/138, 318/341
• US Class Current: 318/696
• CPC Class Codes: G04C 3/14 incorporating a stepping motor G04C3/02 - G04C3/12 take precedence generating timing pulses G04F5/00, G04G3/00; setting G04G5/00; synchronisation G04G7/00; generating commutating pulses in masterclocks G04C13/0463, G04C13/02; slave clocks actuated intermittently by electromechanical step advancing mechanisms G04C13/10; control circuits for stepping motors in general H02P8/00
• CPC Class Codes: G04G 3/02 Circuits for deriving low frequency timing pulses from pulses of higher frequency pulse frequency dividers in general H03K23/00 - H03K29/00
• CPC Class Codes: G04G 5/02 by temporarily changing the number of pulses per unit time, e.g. quick-feed method
• CPC Class Codes: G04G 99/00 Subject matter not provided for in other groups of this subclass
• CPC Class Codes: H02P 8/34 Monitoring operation H02P8/36 takes precedence

Abstract

A system for driving a bipolar stepping motor by a pair of pulse driving currents wherein an output level of a control circuit is selected depending on one of the pulse drive currents applied just prior to the stoppage of the motor by a reset signal, switching of a set of signal transmitting paths for connecting between a reference signal generating circuit and a motor drive circuit is selected depending on an output level of the control circuit, that one of a pair of reference signals produced by the reference signal generating circuit during the operation of the motor which first appears after the release of the stop causes production of the other of the pulse drive currents by the selected path, and a predetermined time period after the release of the stop the pulse drive current of opposite polarity to that of the pulse drive current being applied to the motor which is just about to stop is applied to the motor to positively re-start the operation of the motor at a predetermined time.

Claims

1. A motor driving system comprising:

a reference signal generating circuit for generating a pair of reference signals of different phase from each other;

a motor driving circuit responsive to said pair of reference signals for producing a pair of motor driving signals for causing drive currents of opposite polarity to each other to be alternately fed to a motor;

a signal transmission path switching circuit connected between said reference signal generating circuit and said motor driving circuit for switching the paths which transmit said reference signals to said motor driving circuit;

a control circuit for receiving said motor driving signals at an input thereof and supplying an output thereof as a control signal to said signal transmission path switching circuit, and

a reset circuit connected to said reference signal generating circuit and said control circuit for generating a reset signal which deactuates said reference signal generating circuit and causes said control circuit to produce and maintain an output signal corresponding to the status of the motor driving signals,

whereby the signal transmission path corresponding to the status of the motor driving signal at the time of the reset is selected and the reference signal is transmitted to the motor driving circuit through the selected signal transmission path at the release of the reset.

2. A motor driving system according to claim 1, wherein said system is constructed in the form of a complementary MOS integrated circuit.

3. A motor driving system comprising:

a reference signal generating circuit for producing one of a pair of reference signals of different phase from each other in preference to the other when it is set and thereafter producing said pair of reference signals alternately;

a motor driving circuit responsive to said pair of reference signals to alternately produce a pair of motor driving signals of different phase from each other;

a signal transmission path switching circuit connected between said reference signal generating circuit and said motor driving circuit for switching the paths which transmit said reference signals to said motor driving circuit;

a control circuit for receiving said motor driving signals at an input thereof and supplying an output thereof as a control signal to said signal transmission path switching circuit, and

a reset circuit connected to said reference signal generating circuit and said control circuit for generating a reset signal which deactuates said reference signal generating circuit and causes said control circuit to produce and maintain an output signal corresponding to the motor driving signal applied to said control circuit;

said signal transmission switching circuit being controlled by said maintained signal to select the signal transmission path which allows to transmit said preference reference signal to the motor driving signal which is different from that motor driving signal which has been applied to the control circuit at the time of the reset,

whereby the motor driving signal which is different from that motor driving signal which was present immediately before the reset is produced in preference at the time of the release of the reset.

4. A motor driving system according to claim 3, wherein said motor driving signals actuate a motor for an electronic watch.

5. A motor driving system according to claim 3, wherein said system is constructed in the form of a complementary MOS integrated circuit.

6. A motor driving system according to claim 5, wherein said motor driving signals actuate a motor for an electronic watch.

7. A motor driving circuit comprising:

an oscillator for generating a square wave signal having a given frequency;

a frequency divider connected to said oscillator and including a plurality of cascade-connected flip-flops;

a shaping circuit including a set of gate circuits each receiving desired ones of the outputs of said flip-flops, said set of gate circuits producing a set of reference signals of different phase from each other each having a desired period and pulse width;

a signal transmission path switching circuit including a set of electronic switching circuits having their input terminals connected to the outputs of said gate circuits and having control terminals;

a motor driving circuit connected to the output terminals of said electronic switching circuits and including a set of buffers for producing a set of motor driving signals of different phase from each other;

a control circuit including a latch circuit and transfer gates and receiving said set of motor driving signals at an input thereof and supplying an output thereof to the control terminals of said electronic switching circuits, and

a reset circuit including a switch and connected to said flip-flops and said transfer gates for producing a reset signal which deactuates said flip-flops and renders said transfer gates conductive,

whereby the control signal corresponding to that motor driving signal which has been applied immediately before the reset is supplied to the electronic switching circuits, and the motor driving signal which is different from that motor driving signal which was present immediately before the reset is produced in preference at the time of the release of the reset.

8. A motor driving circuit according to claim 7, wherein said motor signals actuate a motor for an electronic watch.

9. A motor driving circuit according to claim 7, wherein said shaping circuit further includes means for changing over those outputs of the flip-flops which are applied to the gate circuits and determine the pulse widths of the reference signals, whereby the pulse widths of the reference signals can be selected.

10. A motor driving circuit according to claim 7, wherein said reset circuit further includes a gate circuit having its input terminals connected to said reset switch and the output terminals of said shaping circuit, whereby the resetting during the presence of the reference signal is prevented.

11. A motor driving circuit according to claim 7, wherein a portion of the frequency divider, the shaping circuit, the signal transmission path switching circuit, the motor driving circuit and the control circuit are constructed by complementary MOSFET inverters, respectively.

12. A motor driving circuit according to claim 9, wherein a portion of the oscillator, the frequency divider, the shaping circuit, the signal transmission path switching circuit, the motor driving circuit and the control circuit are constructed by complementary MOSFET inverters, respectively.

13. A motor driving circuit according to claim 10, wherein the circuit components used in a portion of the oscillator, the frequency divider, the shaping circuit, the signal transmission path switching circuit, the motor driving circuit, the control circuit and the gate circuit of the reset circuit are constructed by complementary MOSFET inverters, respectively.

14. A motor driving circuit according to claim 7, wherein a portion of the oscillator, the frequency divider, the shaping circuit, the signal transmission path switching circuit, the motor driving circuit and the control circuit are constructed in a complementary MOS integrated circuit structure.

15. A motor driving circuit according to claim 9, wherein a portion of the oscillator, the frequency divider, the shaping circuit, the signal transmission path switching circuit, the motor driving circuit and the control circuit are constructed in a complementary MOS integrated circuit structure.

16. A motor driving circuit according to claim 10, wherein a portion of the oscillator, the frequency divider, the shaping circuit, the signal transmission path switching circuit, the motor driving circuit, the control circuit and the gate circuits of the reset circuit are constructed in a complementary MOS integrated circuit structure.

17. A motor driving circuit according to claim 16, wherein the motor driving currents actuate a motor for an electronic watch.