Viscous fan drive control with integrated speed sensor
US4874072A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 1987 |
| Grant date | Oct 17, 1989 |
| Priority date | — |
| Expiry date | Nov 10, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16D35/024
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A viscous fan clutch (10) is typically employed in a fan drive mechanism within a truck 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 (106) defined by complimentary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving element (196) within the clutch to control the torque transmission there through and thus the speed of the output shaft and fan (34) thereof. Fan speed is regulated by variable current signal applied to a coil (174) within assembly (30) to selectively variably frictionally engage valve element assembly (196) with a grounded thrust surface or reaction member (190) to effect limited displacement of a valve element (198) in response thereto. A fan speed feedback signal is generated by teeth (164) passing in close proximity to a magnetic pick-up (166) is integrated within tether housing (122) and output to control circuit (222) via a conducting path (173 or 183).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.