SOLID STATE POWER CONTROLLER FOR DC PERMANENT MAGNET AND SHUNT FIELD WINDING MOTORS SUPPLIED FROM AN AC SOURCE

• US 3,639,822 A
• Filed: 05/11/1970
• Issued: 02/01/1972
• Est. Priority Date: 05/11/1970
• Status: Expired due to Term

• Current Assignee: Harry W. Brown, Lawrence J. Ryczek, Walter L. Rutchik
• Original Assignee: Harry W. Brown, Lawrence J. Ryczek, Walter L. Rutchik
• Inventors: Ryczek, Lawrence J., Brown, Harry W., Rutchik, Walter L.
• Primary Examiner(s): Lynch, T. E.
• Assistant Examiner(s): Hickey, Robert J.
• Application Number:
  US05/036,124
• Time in Patent Office: 631 Days
• Field of Search: 318/345,331 323/22SC,24,25,22,36
• US Class Current: 388/830
• CPC Class Codes: H02P 25/10 Commutator motors, e.g. repulsion motors
• CPC Class Codes: H02P 7/293 using phase control H02P7/295 takes precedence
• CPC Class Codes: Y10S 388/919 Triggered by resistor or capacitor
• CPC Class Codes: Y10S 388/937 Hand tool

Abstract

A solid state switching circuit and power controller for permanent magnet and shunt field winding motors used in portable power tools and the like. The power controller employs a bidirectional thyristor triode and trigger diode for varying the current supplied to the motor armature, and a full-wave rectifier bridge to establish unidirectional current flow through the motor armature on opposite half cycles of the AC power supply. A resistor across the AC terminals of the rectifier bridge enhances control action under light loads.

Claims

1. In a controller for connecting the armature of a DC permanent magnet or shunt-type motor to a source of alternating voltage supply and varying the current supplied thereto, in combination:

an actuating lever, switch means responsive to a given amount of initial movement of said actuating lever to connect the controller to a source of alternating voltage supply, current control means including a controllable bidirectional semiconductor device and a control network responsive to additional movement of said actuating lever to control the flow of current through said semiconductor device during opposite half-cycles of connected alternating voltage supply in accordance with the amount of additional movement of said actuating lever, a full wave rectifier bridge connected in circuit with said semiconductor device and with the armature of a permanent magnet motor to insure current flow through such armature always in the same direction during opposite half-cycles of the alternating voltage supply, and a resistor connected across the AC input terminals of said rectifier bridge.