Conveyance with electronic control for left and right motors

• US 5,012,165 A
• Filed: 02/21/1990
• Issued: 04/30/1991
• Est. Priority Date: 11/04/1986
• Status: Expired due to Fees

• Current Assignee: John L. Lautzenhiser, Lloyd L. Lautzenhiser
• Original Assignee: John L. Lautzenhiser, Lloyd L. Lautzenhiser
• Inventors: Lautzenhiser, Lloyd L., Lautzenhiser, John L.
• Primary Examiner(s): Shoop, Jr., William M.
• Assistant Examiner(s): Wysocki, A. Jonathan
• Application Number:
  US07/482,461
• Time in Patent Office: 433 Days
• Field of Search: 318/52, 318/56, 318/57, 318/67, 318/68, 318/69, 318/87, 318/53, 318/58, 318/269, 318/272, 318/61, 318/64, 318/259, 318/99, 318/257, 318/55, 318/260, 318/365, 318/369, 318/375, 180/6.3, 180/6.48, 180/19.1, 180/19.3, 180/60, 180/65.1, 180/142, 180/143, 180/79.1
• US Class Current: 318/53
• CPC Class Codes: A61G 2203/14 Joysticks
• CPC Class Codes: A61G 5/045 Rear wheel drive
• CPC Class Codes: A61G 5/1018 on the running surface
• CPC Class Codes: A61G 5/1032 engaging an element of the drive or transmission, e.g. drive belt, electrodynamic brake
• CPC Class Codes: A61G 5/1054 Large wheels, e.g. higher than the seat portion
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B60L 7/00 Electrodynamic brake systems for vehicles in general
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A conveyance (10) is provided with automatic limiting (223) of the rate of change in power supplied to first (26a or 232a) and second (26b) motors, whether the motors are electrical or hydraulic; and dynamic braking of electric motors (26a and 26b) is achieved by shorting a motor winding (150a) during a portion (233a) of an interval (217a) between power pulses (207a) of a pulse-width-modulated driving voltage (209a).

Claims

1. A conveyance (10) having first (12a) and second (12b) propulsion elements, and having first (26a or 232a) and second (26b, etc.) motors that are operatively connected to said first and second propulsion elements, the improvement which comprises:

motor control means (332a, 334a, or 336a), being connected to said first and second motors and to a source (60) of power, for separately and variably supplying power to said first and second motors;

manual control means (352), being operatively connected to said motor control means, for selectively and variably controlling said motor control means; and

change limiting means (223), being operatively connected to said motor control means, for limiting the rate of change in differences in power supplied to said first and second motors, while permitting larger rates of change in power supplied to said motors when rates of changes in power supplied to said first and second motors are generally equal.

2. A conveyance (10) as claimed in claim 1 in which said change limiting means comprises means (224) for adjusting said limiting of said rate of change in differences in power.

3. A conveyance (10) as claimed in claim 1 in which said connection of said manual control means (352) to said motor control means (332a, 334a, or 336a) comprises first (98a) and second (98b) control signal conductors;

said manual control means (352) includes means (76a and 76b) for producing first and second control signals in respective ones of said first and second control signal conductors; and

said means for limiting the rate of change in differences in power supplied to said motors (26a, 232a, 26b, etc.) includes means (224) for limiting the rate of change in the difference in said control signals.

4. A conveyance (10) as claimed in claim 1 in which said connection of said manual control means (352) to said motor control means (332a, 334a, or 336a) comprises first (98a) and second (98b) control signal conductors;

said manual control means (352) includes means (76a and 76b) for producing first and second control signals in respective ones of said first and second control signal conductors; and

said change limiting means (223) includes means, comprising a capacitor (222), for limiting the rate of change in the difference of said control signals.

5. A conveyance (10) as claimed in claim 1 in which said connection of said manual control means (352) to said motor control means (332a, 334a, or 336a) comprises first (98a) and second (98b) control signal conductors;

said manual control means includes means (76a and 76b) for producing first and second control signals in respective ones of said first and second control signal conductors; and

said change limiting means (223) includes means, comprising a capacitor (222), for comprising means (224) for limiting current flow into said capacitor, for limiting the rate of change in the difference of said control signals.

6. A conveyance (10) as claimed in claim 1 in which said connection of said manual control means (352) to said motor control means (332a, 334a, or 336a) comprises first (98a) and second (98b) control signal conductors;

said manual control means includes means (76a and 76b) for producing first and second control signals in respective ones of said first (98a) and second (98b) control signal conductors; and

said change limiting means (223) includes means, comprising a capacitor (222), and comprising adjustable means (224) for selectively limiting current flow into said capacitor, for adjustably limiting the rate of change in the difference of said control signals.

7. A conveyance (10) as claimed in claim 1 in which said first and second motors comprise a fluid motor (232a);

said source of power comprises a source (338a) of fluid power; and

said supplying of power to said motors comprises supplying fluid power to said fluid motor.

8. A conveyance (10) as claimed in claim 1 in which said first and second motors comprise first (26a) and second (26b) electric motors;

said source of power comprises a source (60) of electrical power; and

said supplying of power to said motors comprises supplying electrical power to said electric motors.

9. A conveyance (10) as claimed in claim 1 in which said first and second motors comprise first (26a) and second (26b) electric motors;

said source of power comprises a source (60) of electrical power; and

said supplying of power to said motors comprises supplying pulses (207a) of electrical power supplied to said electric motors that are interspersed with intervals (217a) of no power.

10. A conveyance (10) as claimed in claim 1 in which said first (26a) and second (26b) motors comprise first (26a) and second (26b) electric motors;

said source of power comprises a source (60) of electrical power;

said supplying of power to said motors comprises supplying pulses (207a) of electrical power supplied to said electric motors that are interspersed with intervals (217a) of no power; and

said conveyance comprises means (72) for pulse-width modulating said pulses.

11. A conveyance (10) as claimed in claim 1 in which said first and second motors comprise electric motors (26a and 26b);

and

said conveyance includes means for dynamically braking one of said motors as a function of a reduction in said power supplied to said one motor when said power to said one motor is selectively reduced.

12. A conveyance (10) as claimed in claim 1, in which said first and second motors comprise electric motors (26a, and 26b);

said motor control means comprises means for dynamically braking said motors; and

said motor control means comprises means for varying said dynamic braking inversely with respect to said variable supplying of said power.

13. A conveyance (10) as claimed in claim 1 in which said first and second motors comprise electric motors (26a, and 26b);

said supplying of power to said motors comprises means (332a) for supplying pulses (207a) of electrical power to said electric motors that are interspersed with intervals (217a) of no power;

said motor control means comprises means for modulating the width (211a) of said pulses to one of said motors in accordance with selective positioning of said manual control means; and

said conveyance includes means (354a or 356a) for dynamically braking said one electric motor as a function of reduction in said width of said pulses to said one motor.

14. A method for controlling power that is supplied to first (26a and 232a) and second (26b) motors that are drivingly connected to propulsion elements (12a and 12b) of a conveyance (10), which method comprises:

(a) manually and variably controlling (76a) said supplying of power to said first and second motors;

(b) automatically limiting (223) the rate of change in the difference in said power supplied to said first and second motors; and

(c) permitting larger rates of changes in said power supplied to said first and second motors when the rates of changes in power supplied to said first and second motors are generally equal.

15. A method as claimed in claim 14 in which said method further comprises adjusting said limiting of said rate of change in the difference in said power.

16. A method as claimed in claim 14 in which said manually and variably controlling of said supplying of power comprises manually and variably controlling first and second control signals;

said automatic limiting step comprises automatically limiting the rate of change in the difference in said control signals; and

said permitting step comprises permitting larger rates of change in said rate of change in the difference in said control signals when said rates of change of said control signals are generally equal.

17. A method as claimed in claim 14 in which said manually and variably controlling of said supplying of power comprises manually and variably controlling first and second control signals;

said automatic limiting step comprises automatically limiting the rate of change in the difference in said control signals; and

said step of automatically limiting comprises charging a capacitor (222).

18. A method as claimed in claim 14 in which said manually and variably controlling of said supplying of power comprises manually and variably controlling first and second control signals;

said automatic limiting step comprises automatically limiting the rate of change in the difference in said control signals;

said step of automatically limiting comprises charging a capacitor (222); and

said method further comprises adjustably limiting the rate of said charging of said capacitor.

19. A method as claimed in claim 14 in which said method further comprises dynamically braking one of said motors as a function of a reduction in said power supplied to said one motor.

20. A method as claimed in claim 14 in which said step of supplying power to said motors (26a and 26b) comprises supplying pulses (207a) of electrical power to said motors, and pulse-width modulating (72) the width (211a) of said pulses;

and

said method further comprises dynamically braking one of said motors as a function of reduction in said width of said pulses to said one motor.

21. A method as claimed in claim 14 in which said step of supplying power to said motors (26a and 26b) comprises supplying pulses (207a) of electrical power to said motors, and pulse-width modulating said pulses;

said controlling step comprises reducing the width (211a) of said pulses supplied to one of said motors, and simultaneously increasing the width (211a) of said pulses supplied to the other of said motors; and

said method further comprises dynamically braking both of said motors, and varying said dynamic braking of said motors inversely to said reductions and increases in said width of said pulses.