US 5,493,191 A · B-type actuator with time out

Abstract

An improved actuator (10) wherein movement of an external potentiometer (R.sub.x) to drive a bi-directional motor (50) and move an attached member starts a timer (68). When a predetermined time period has elapsed, the actuator cuts power to the drivers (U1) of the motor, thereby putting the system into a "sleep" mode in which a minimum amount of current is drawn. If the external potentiometer was moved so as to cause an end of travel position of the member and the motor stalls, the actuator maintains this stall condition only until expiration of the predefined time period at which time the sleep mode is initiated. This sleep mode is thereafter maintained until power is reset or until the position of the external control potentiometer is changed. The time-out period is set to allow for full movement of the vane as well as to compensate for any uncertainty as to whether an end of travel position has been reached.

Claims15

Dependent claims

An actuator circuit for driving an electric motor to control the position of an output shaft of the motor in response to a signal from an external device indicative of a desired position of the output shaft, said actuator comprising:

a power supply;
a circuit for detecting a difference between a desired position of the output shaft and the actual position of the output shaft;
a motor driving circuit electrically coupled to said detecting circuit and to said electric motor;
a timer circuit electrically coupled to said detecting circuit and to said driving circuit;
and
switch means connected between said power supply and said driving circuit, said switch responsive to said detection circuit to facilitate the supply of power to said driving circuit, said switch responsive to said timer circuit for interrupting the supply of power to said driving circuit.

3 more elements

An actuator circuit for driving a bi-directional electric motor to control the rotational position of an output shaft of said motor in response to a signal from a potentiometer indicative of the desired position of said output shaft, said shaft being rotatable to a plurality of positions between a pair of opposing end of travel positions, said actuator circuit comprising:

a power supply;
a circuit for detecting a difference between a desired position of said output shaft and the actual position of said shaft, said circuit for detecting including a feedback signal generation means for generating a signal indicative of the actual position of said output shaft;
a motor driving circuit electrically coupled to said detecting circuit and to said electric motor;
a timer circuit electrically coupled to said detecting circuit and to said driving circuit;
switch means electrically coupled to said power supply and said driving circuit, said switch means responsive to said detection circuit to facilitate the supply of power to said driving circuit, said switch responsive to said timer circuit for interrupting the supply of power to said driving circuit when one of said end of travel positions has been reached and a predetermined time period expires.

2 more elements

Dependencies are inferred from the claim text.

B-type actuator with time out

Life of this patent

B-type actuator with time out

Life of this patent

Abstract

Claims15