Abstract: A dust seal is disposed in a rotational control apparatus for sealing a pressurized chamber, such as a pressure chamber in a pneumatic on/off fan clutch. The dust seal is an annular elastomeric member disposed between first and second members rotating about a first axis. The seal is for sealing against ingress of foreign matter into a pressure chamber that is formed between the first and second members, wherein the first member has an annular extension and the second member has a radially extending surface. The seal comprises a center base section having a first side and a second side, a radially inner upright section and a radially outer upright section. The radially inner upright section extends generally perpendicularly from the first side of the center base section and the radially outer upright section extends from the first side of the center base section at an acute angle relative to the center base section.

Abstract: A dust seal is disposed in a rotational control apparatus for sealing a pressurized chamber, such as a pressure chamber in a pneumatic on/off fan clutch. The dust seal is an annular elastomeric member disposed between first and second members rotating about a first axis. The seal is for sealing against ingress of foreign matter into a pressure chamber that is formed between the first and second members, wherein the first member has an annular extension and the second member has a radially extending surface. The seal comprises a center base section having a first side and a second side, a radially inner upright section and a radially outer upright section. The radially inner upright section extends generally perpendicularly from the first side of the center base section and the radially outer upright section extends from the first side of the center base section at an acute angle relative to the center base section.

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).