Closed loop pulse modulated viscous fan control
US4828088A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 1987 |
| Grant date | May 9, 1989 |
| Priority date | — |
| Expiry date | May 18, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01P7/042
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A viscous fan clutch (10) is typically employed in a fan drive mechanism within in a truck or or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (100) defined by complementary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving member (158) within the clutch to control the torque transmission therethrough and thus the speed of the output shaft (and fan 34) thereof. Fan speed is regulated as a function of a sensed temperature of the host engine by a control circuit (176) which senses fan speed and coolant fluid temperature and generates a speed error signal as a function of temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.