US 5,765,672 A · Overheating protection device for rotational control apparatus

Abstract

A device (10) is disclosed for intercepting the input of a system (23) of an internal combustion engine (12) normally provided to a solenoid valve (22) for actuating a fan clutch (20) when rotation of a fan (16) is desired. The input is received by terminals (42, 43) and is conditioned and passed on to a timer (96) and a controller (97). A vacuum switch (24) senses whether the fan (16) is rotating and provides a second input to the controller (97). In the event that an input is provided by the system (23) and the time delay signal has been provided by the timer (96) and also in the event that an input is provided by the system (23), the time delay has expired, and the second input is provided by the vacuum switch (24), the controller (97) provides an actuation output to terminals (71, 73) connected to the solenoid valve (22) by use of actuation provisions (98) to actuate the fan clutch (20). After the time delay signal is no longer provided by the timer (96), the actuation output is interrupted to the fan clutch (20) if one or both of the first and second inputs are interrupted. Thus, device (10) interrupts the actuation of the fan clutch (20) in the event that the fan (16) is unable to rotate for any reason and thereby provides overheating protection for the fan clutch (20).

Claims34

Dependent claims

Device for interrupting the engagement of a rotational control apparatus having a rotatable output in the event that the output is not free to rotate comprising, in combination:

input terminals for receiving a first input indicating that engagement of the rotational control apparatus is desired to rotate the output;
a controller;
a timer for providing a time delay signal to the controller until a delay time has expired;
means for conditioning the first input received by the input terminals and for passing the conditioned input to the timer and simultaneously to the controller;
means for sensing the rotation of the output of the rotational control apparatus and providing a second input to the controller;
and means for providing an actuation output to the rotational control apparatus for engaging the rotational control apparatus in the event that the first input is received and the time delay signal has been provided to the controller and in the event that the first input is received, the time delay has expired, and the second input has been provided to the controller.

3 more elements

Method for interrupting the engagement of a rotational control apparatus having a rotatable output in the event that the output is not free to rotate comprising the steps of:

receiving a first input indicating that engagement of the rotational control apparatus is desired to rotate the output;
providing a controller;
providing a timer for providing a time delay signal to the controller until a delay time has expired;
conditioning the received first input and passing the conditioned input to the timer and simultaneously to the controller;
sensing the rotation of the output of the rotational control apparatus and providing a second input to the controller;
and providing an actuation output to the rotational control apparatus for engaging the rotational control apparatus in the event that the first input is received and the time delay signal has been provided to the controller and in the event that the first input is received, the time delay has expired and the second input has been provided to the controller.

3 more elements

Dependencies are inferred from the claim text.

Overheating protection device for rotational control apparatus

Life of this patent

Overheating protection device for rotational control apparatus

Life of this patent

Abstract

Claims34