公开(公告)号：US3644793A

公开(公告)日：1972-02-22

申请号：US3644793D

申请日：1970-05-01

Applicant: CUTLER HAMMER INC

Inventor： ILK RONALD J

IPC: H03K17/725 ,  H01H47/18

CPC classification number: H03K17/725 ,  Y10T307/957

Abstract: An AC interval timer for controlling any AC load such as the lamp of an infrared heating device, motor, solenoid valve or the like. The timing system is supplied through a rectifier from the same AC source that supplies the load and provides a timed ''''on'''' cycle after momentary operation of an activating switch. Features include a pulse input that causes latching of the load ''''on'''' and prevents false triggering, a timing circuit that incorporates temperature compensation and good power supply stability characteristics, and a reset clamp to insure accurate repeatability and recycling.

公开(公告)号：US3586947A

公开(公告)日：1971-06-22

申请号：US3586947D

申请日：1969-04-09

Applicant: CUTLER HAMMER INC

Inventor： ILK RONALD J ,  RUTCHIK WALTER L

IPC: H02P25/14 ,  H02P5/16

CPC classification number: H02P25/145 ,  Y10S388/918 ,  Y10S388/93

Abstract: A full-wave adjustable motor speed control system with feedback for automatic regulation of the speed of an AC motor such as a series or universal motor. A bidirectional thyristor triode in series with the motor armature winding is controlled by a firing circuit operated by a ramp and pedestal voltage. The ramp may be set at a fixed value whereas the pedestal is adjusted for desired speed and regulated by a feedback signal. This feedback signal is developed in an amplifying feedback circuit that is adjusted to eliminate unwanted characteristics and to provide a true speed signal proportional to motor counter EMF.