Global Patent Index - EP 0281616 A4

EP 0281616 A4 19890126 - SERVO-SYSTEM.

Title (en)

SERVO-SYSTEM.

Title (de)

SERVOSYSTEM.

Title (fr)

SYSTEME D'ASSERVISSEMENT.

Publication

EP 0281616 A4 19890126 (EN)

Application

EP 87906239 A 19870817

Priority

US 90409686 A 19860904

Abstract (en)

[origin: WO8801763A1] A device for determining the rotational speed of an object (10) adapted to rotate about a predetermined rotation axis (12). The device is particularly useful as a servo control for motors, such as motors having optical tachometers, tone wheels and for brushless DC motors in which the commutation Hall sensors (16) are being used in lieu of a tachometer. Sensor and other positional errors are substantially eliminated by sensing the time intervals between at least two rotational positions of the rotor through a full rotation of the rotor, and averaging the time intervals of each time measurement between succeeding rotor positions over the prior revolution of the rotor. The average is compared to a preset value representative of the desired speed, and the current applied to the servo control circuit is adjusted, if necessary, in order to increase or decrease the speed of the rotor to the desired speed.

IPC 1-7

G05B 5/00; H02K 27/20; H02P 5/00

IPC 8 full level

G01P 11/00 (2006.01); H02P 6/06 (2006.01); H02P 6/16 (2006.01)

CPC (source: EP)

G01P 11/00 (2013.01); H02P 6/06 (2013.01); H02P 6/17 (2016.02)

Citation (search report)

Designated contracting state (EPC)

DE FR GB IT

DOCDB simple family (publication)

WO 8801763 A1 19880310; EP 0281616 A1 19880914; EP 0281616 A4 19890126; JP H01500877 A 19890323

DOCDB simple family (application)

US 8702071 W 19870817; EP 87906239 A 19870817; JP 50565687 A 19870817