Patent Number: 6,310,449

Title: Device having a variable-speed motor

Abstract: In a device (1) having a variable-speed motor (2), a single switchingdevice (9) has been provided for influencing the speed of the motor andfor generating turn-off voltage transients (SP) on a coil terminal (3b) ofthe motor. The turn-off voltage transients can be applied to a voltageboosting circuit (14) for generating a d.c. control voltage required fordriving a control electrode of the single switching device. This d.c.control voltage is supplied to the control electrode of the switchingdevice with the aid of a control pulse generator (10). The d.c. controlvoltage reaches a higher value than the d.c. supply voltage (V) applied tothe device (1). Preferably, the device includes a starting circuit (20),by which a minimum d.c. control voltage, required for the controlelectrode of the single switching device, can be generated for the firsttime in order to drive the single switching device into its conductivestate.

Inventors: Dorfer; Roland (Keutschach, AT)

Assignee:

International Classification:

Expiration Date: 10/32013