Speed control for brushless repulsion motor

• US 6,049,187 A
• Filed: 01/04/1999
• Issued: 04/11/2000
• Est. Priority Date: 03/26/1993
• Status: Expired due to Fees

• Current Assignee: Dynamotors Incorporated
• Original Assignee: Dynamotors Incorporated
• Inventors: Haner, Lambert
• Primary Examiner(s): Ro, Bentsu
• Application Number:
  US09/223,981
• Time in Patent Office: 463 Days
• Field of Search: 318/138, 318/254, 318/430, 318/439, 318/700, 318/720, 318/721, 318/723, 318/724, 318/725, 318/726
• US Class Current: 318/725
• CPC Class Codes: H02K 29/10 using light effect devices
• CPC Class Codes: H02K 37/00 Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors
• CPC Class Codes: H02P 1/24 for starting an individual ac commutator motor starting of ac/dc commutator motors H02P1/18
• CPC Class Codes: H02P 25/102 Repulsion motors
• CPC Class Codes: H02P 6/00 Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor vector control H02P21/00

Abstract

An armature mounted armature speed control system for a brushless repulsion motor of the type including a series of coil switches on the armature for shorting a succession of armature coils and detectors on the armature for operating each of the switches when the armature coil shorted by a switch is at a selected rotational position, the system comprising: a ring counter with sequentially energized output lines for receiving signals in sequence at a rate controlled by the reference frequency of count pules at the input of the counter, means for operating the switches in sequence by the counter created signals to control the speed of the armature at a set point and a selector switch shiftable upon receipt of a shift signal between a first condition with the signals from said counter operating the coil switches and a second condition with the detectors operating the coil switches.

Claims

1. An armature mounted armature speed control system for a brushless repulsion motor of the type including a series of coil switches on said armature for shorting a succession of armature coils and detectors on said armature for operating each of said switches when the armature coil shorted by said switch is at a selected rotational position, said system comprising:

a ring counter with sequentially energized output lines for receiving signals in sequence at a rate controlled by the reference frequency of count pules at the input of said counter, means for operating said switches in sequence by said counter created signals to control the speed of said armature at a set point determined by said reference frequency, and a selector switch shiftable upon receipt of a shift signal between a first condition with said signals from said counter operating said coil switches and a second condition with said detectors operating said coil switches.

2. A speed control system as defined in claim 1 including means for adjusting the frequency of said count pulses at the input of said ring counter to change the speed of said armature.

3. A speed control system as defined in claim 2 including means for sensing a decrease of the speed of said armature to shift said selector switch from said first condition to said second condition.

4. A speed control system as defined in claim 3 wherein said sensing means is an up/down counter with the up count input operated by said count pulses and the down count input operated by pulses at a detected frequency proportional to the actual speed of said armature and a spill over gate to create said shift signal when said up count exceed said down count by a selected number.

5. A speed control system as defined in claim 4 wherein said spillover gate includes means for inhibiting said up/down counter when said shift signal is created.

6. A speed control system as defined in claim 2 wherein said reference frequency is created by a voltage controlled oscillator.

7. A speed control system as defined in claim 6 wherein said oscillator is in a fixed position and a transmission mechanism including a fixed element and a rotating element on said armature transmits said count pulses to said armature.

8. A speed control system as defined in claim 1 including means for sensing a decrease of the speed of said armature to shift said selector switch from said first condition to said second condition.

9. A speed control system as defined in claim 8 wherein said sensing means is an up/down counter with the up count input operated by said count pulses and the down count input operated by pulses at a detected frequency proportional to the actual speed of said armature and a spill over gate to create said shift signal when said up count exceed said down count by a selected number.

10. A speed control system as defined in claim 9 wherein said spillover gate includes means for inhibiting said up/down counter when said shift signal is created.

11. A speed control system as defined in claim 8 wherein said reference frequency is created by a voltage controlled oscillator.

12. A speed control system as defined in claim 11 wherein said oscillator is in a fixed position and a transmission mechanism including a fixed element and a rotating element on said armature transmits said count pulses to said armature.

13. A speed control system as defined in claim 1 wherein said reference frequency is created by a voltage controlled oscillator.

14. A speed control system as defined in claim 13 wherein said oscillator is in a fixed position and a transmission mechanism including a fixed element and a rotating element on said armature transmits said count pulses to said armature.

15. A method of operating a brushless repulsion motor of the type including a series of coil switches on the armature for shorting a succession of armature coils and detectors on said armature for operating each of said switches when the armature coil shorted by said switch is at a selected rotational position, said method comprises the steps of:

(a) maintaining a set armature speed by deactivating said detectors and operating said switches in sequence at a set frequency;

(b) sensing when said armature speed is reduced by reaching maximum torque; and

,

(c) then operating said switches by closing said switches when the respective coils are in said selected rotational position by activating said detectors and deactivating said set frequency operation of said switches.

16. The method as defined in claim 15 including the step of adjusting said set frequency.