Accession Number:

ADD005150

Title:

Fan Drive System.

Descriptive Note:

Patent,

Corporate Author:

DEPARTMENT OF THE ARMY WASHINGTON D C

Personal Author(s):

Report Date:

1977-12-13

Pagination or Media Count:

5.0

Abstract:

A variable speed fan drive mechanism for an engine coolant system controlled by temperature and fan speed signals. The mechanism includes a hydrostatic pump-motor unit hydrostatic transmission powered by the engine, for transmitting power to the fan. Mechanical signals related to coolant temperature and fan speed are supplied to a comparator mechanism that delivers a mechanical output control signal. The output control signal is magnified and applied as a control force to vary the displacement of the pump in the hydrostatic unit. The comparator mechanisms has the effect of negating engine speed as a control force. Thus, high engine speeds that would tend to produce unduly large hydraulic flows through the pump-motor circuit are reflected in high fan speed signals fed into the comparator mechanism, which produces a corrected output signal that appropriately reduces pump dislacement to thus reduce the fan speed to low energy consumption levels. Author

Subject Categories:

  • Air Conditioning, Heating, Lighting and Ventilating

Distribution Statement:

APPROVED FOR PUBLIC RELEASE