BATTERY RUN D-C MOTOR SPEED CONTROL, CHARGING AND STEERING SYSTEMS

• US 3,736,480 A
• Filed: 02/11/1972
• Issued: 05/29/1973
• Est. Priority Date: 02/11/1972
• Status: Expired due to Term

• Current Assignee: Joo C. Lee
• Original Assignee: Joo C. Lee
• Inventors: Lee, Joo C.
• Primary Examiner(s): Miller, J. D.
• Assistant Examiner(s): Huberfeld, H.
• Application Number:
  US05/225,565
• Time in Patent Office: 473 Days
• Field of Search: 318/51,105,106,107,108,109,139,339,341 320/48,57,59,60 321/2
• US Class Current: 318/51
• CPC Class Codes: B63H 23/24 electric dynamo-electric machines H02K
• CPC Class Codes: H02M 3/3385 with automatic control of output voltage or current H02M3/33561 takes precedence

Abstract

A first system for energizing a d-c motor includes a switching network for passing energy to and from a battery, and to the d-c motor. The battery can energize the motor over the switching network, and the battery can be recharged over a first channel supplied with a-c energy which is rectified and passed through the switching network to the battery. A second channel provides power control to regulate the level of d-c energy to the motor and thus control motor speed, and also provide an indication of the battery power available. A third channel energizes an r-f oscillator over the switching network from the battery. The a-c voltage from the r-f oscillator is rectified, filtered and applied to an alternate d-c motor. Another system includes a pair of d-c motor groups, with two separate channels for energizing each motor group simultaneously or independently. This provides a steering function in addition to the optional battery charging speed control arrangements already described.

Claims

1. A system for regulating energization of a d-c motor from a battery and also regulating charging of the battery, comprising:

a switching network, coupled to the battery and to the motor, having a plurality of switches for regulating energy transfer to and from the battery and to the motor;

a first channel, coupled between an input line for receiving a-c energy and the switching network, includg an input rectifier coupled to the input line, an oscillator coupled to the input rectifier for providing a-c energy, and an output rectifier connected to receive the a-c energy over a transformer and pass d-c energy to the switching network, thus providing d-c energy for charging the battery; and

a second channel, connected to receive d-c energy at a constant level from the switching network and to pass d-c energy at a variable power level over the switching network to the motor, thus controlling motor speed.

2. An energization system as claimed in claim 1, and in which said second channel includes a driver amplifier and a power amplifier coupled in series to provide the variable power level d-c energy, a first sensing means connected between the switching network and the driver amplifier to provide a first control signal when d-c energy is being supplied to the driver amplifier, a second sensing means coupled to the output side of the driver amplifier for providing a second control signal when the driver is passing energy to the power amplifier, and indicating means coupled both to the first sensing means and to the second sensing means, for providing a normal indication only when both said first and second control signals are present.

3. An energization system as claimed in claim 1, in which said first channel includes a voltage regulator coupled in series between the input rectifier and the oscillator, a feedback winding on said transformer, and means for passing a feedback signal from the feedback winding to the voltage regulator, to provide effective regulation of the battery charging level notwithstanding changes in load and losses in the oscillator circuit.

4. An energization system as claimed in claim 1, and further comprising a third channel, connected between the switching network and a second d-c motor for energizing the second motor from the battery, including means coupled to the switching network for providing an a-c signal from energy supplied by the battery, additional windings on said transformer, a converter connected to receive a-c energy over said additional windings from the means for production the a-c signals, and a filter, coupled between the converter and the second motor, for reducing the a-c ripple in the d-c voltage passed to the motor.

5. A system for regulating energization of a d-c motor from a battery, and also regulating charging of the battery, comprising:

a switching network, coupled to the battery and to the motor, including a plurality of switches for regulating the motor drive and battery charging functions;

a first channel connected between an input line for receiving a-c energy and the switching network, including an input rectifier stage coupled to the a-c input line, an oscillator connected to operate and provide a-c energy upon energization by the input rectifier, a transformer having primary and secondary windings, with the primary winding coupled to the oscillator, an output rectifier coupled between the secondary winding and the switching network to pass d-c energy to the switching network when a-c energy is supplied to the input line; and

a second channel for both controlling the amount of d-c power supplied to drive the motor or battery and to provide an indication such power is actually being supplied, comprising an input line coupled to the switching network for receiving a d-c voltage at a constant level, a driver amplifier stage and a power amplifier stage, both coupled to the input line for receiving constant level d-c energy, and an output line coupled between the power amplifier and the switching network to return d-c energy at a level determined by the operation of the driver amplifier stage, thus to afford regulation of the amount of energy for charging the battery and for driving the motor.

6. An energization system as claimed in claim 5, in which the first channed further includes a voltage regulator coupled between the input rectifier and the oscillator to afford regulation of the energy supplied to the oscillator, a feedback winding on said transformer, and means for passing a feedback signal from the feedback winding to the voltage regulator, thus affording regulation which is a function of the load imposed over the transformer and is virtually independent of the losses in the oscillator circuit.

7. An energization system as claimed in claim 5, and further comprising a third channel, connected between said switching network and a second d-c motor, comprising additional primary and secondary windings on said transformer, a second oscillator coupled between the switching network and said additional primary winding to receive d-c energy from the battery and pass a-c energy to the additional secondary windings, a converter coupled to the additional secondary winding for providing d-c energy, and a filter coupled between the converter and the second motor, thus providing energization of the second motor from the same battery.

8. An energization system as claimed in claim 5, and in which said second channel comprises a resistor coupled between said input line and a reference line, a first transistor having its emitter-base circuit coupled to opposite ends of said resistor, to provide current flow through the emitter-collector path of the first transistor when current is supplied over the resistor to the driver amplifier stage, and indicator means coupled to said first transistor for providing an operating signal when current is flowing over the first resistor to energize the driver amplifier.

9. A system as claimed in claim 8, and further comprising a Zener diode in said second channel, coupled between said reference line and ground, so that the operating signal is provided only when the energization to the driver amplifier is at a voltage level at least equal to the voltage drop across said Zener diode.

10. An energization system as claimed in claim 8, and further comprising a second transistor having its base coupled through a diode to the output line from the driver amplifier stage, and its emitter-collector path coupled in series with said indicator means and said first transistor, so that the operating signal from the indicator is provided only when energy is being supplied to the driver amplifier and the driver amplifier is also passing energy over its output line to the power amplifier stage.

11. An energization system as claimed in claim 10, in which the indicator means is a lamp, further comprising a photocell positioned to produce an output signal responsive to the incident light from said lamp, and a meter coupled to said photocell to provide an indication of the illumination level of the photocell, thus providing an indication of the operating level of the driver amplifier stage.

12. An energization system as claimed in claim 11, and further comprising an alarm, connected for energization when the operating indication on said meter drops below a predetermined minimum level.

13. A system for regulating energization of a pair of d-c motor groups from a battery and also for regulating charging of the battery, comprising:

a switching network, coupled to the battery and to both motor groups, having a plurality of switches for regulating energy transfer to and from the battery and to the motor groups;

a first channel, connected to receive d-c energy from a pair of input d-c lines and to pass output a-c energy to the switching network, including a first switching circuit connected to provide a pulse signal, and a first power amplifier circuit connected to amplify the pulse signal for passage through the switching network, thus energizing one of the two motor groups; and

a second channel, connected to receive d-c energy over the two input d-c lines and to pass output a-c energy to the switching netowork, including a second switching circuit connected to provide a pulse signal when energized by the d-c voltage, and a second power amplifier circuit connected to amplify the pulse signal for passage through the switching network to energize the second of the two motor groups, thus providing drive for both motor groups in the system.

14. An energization system as claimed in claim 13, and further comprising a left-right steering switch connected in said switching network, including a movable contact coupled to one of the d-c input conductors, and a pair of fixed contacts each of which is coupled to a different conductor for energizing one of the two motor groups, so that closure of the left-right switch in one position energizes one of the motor groups at full level and in the other position energizes the other of the motor group at its full level, to provide a steering function.

15. An energization system as claimed in claim 13, and further comprising a bypass switch connected in said switching network, effective when closed to shunt both the first and second channels to pass full d-c energization from the input conductors directly to the motor groups for full speed operation.

16. An energization system as claimed in claim 13, and further comprising frequency adjusting means in the switching circuit of each channel, operable to adjust the frequency of the pulses provided to the power amplifier, a duty cycle adjust means in each switching circuit, operable to regulate the portion of each pulse actually passed to the power amplifier, and means for intercoupling the duty cycle adjust and frequency adjusting means so that at the lower end of the duty cycle adjust range, the frequency of the pulses is gradually increased to obviate intermittent actuation of the d-c motors.

17. An energization system as claimed in claim 13, and further comprising a third channel, connected to receive a-c energy over an input line and provide d-c energy over a rectifier circuit, and a charge-run switch in said switching network, operable in one position to pass d-c energy from the battery to the first and second channels and in the second position to pass energy from the rectifier circuit to the battery, thus affording a charge function in the system.

18. A system for regulating energization of a d-c motor from a battery and also regulating charging of the battery, comprising:

a switching network, coupled to the battery and to the motor, having a plurality of switches for regulating energy transfer to and from the battery and to the motor;

a first channel, coupled between an input line for receiving a-c energy and the switching network, including an input rectifier coupled to the input line, an oscillator coupled to the input rectifier for providing a-c energy, and an output rectifier connected to receive the a-c energy over a transformer and pass d-c energy to the switching network, thus providing d-c energy for charging the battery; and

a second channel, including a rheostat connected to the switching network, for passing d-c energy at a variable power level, depending upon the setting of the rheostat, to the motor or to the battery.