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Enhanced Air Cooling System for Hydraulic Fluids

IP.com Disclosure Number: IPCOM000053047D
Original Publication Date: 1981-Aug-01
Included in the Prior Art Database: 2005-Feb-12
Document File: 2 page(s) / 80K

Publishing Venue

IBM

Related People

Gupta, OR: AUTHOR [+2]

Abstract

When hydraulic fluid is controlled at an optimum operating temperature, the hydraulic system is characteristically more reliable, repeatable, etc. Hydraulic oil systems generally run at relatively high temperatures, i.e., over 100 degrees F, in order to reduce viscous losses (pressure drop). In general, hydraulic systems also tend to minimize flow rates by operating at high pressures.

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Enhanced Air Cooling System for Hydraulic Fluids

When hydraulic fluid is controlled at an optimum operating temperature, the hydraulic system is characteristically more reliable, repeatable, etc. Hydraulic oil systems generally run at relatively high temperatures, i.e., over 100 degrees F, in order to reduce viscous losses (pressure drop). In general, hydraulic systems also tend to minimize flow rates by operating at high pressures.

When the design criteria is to cool hydraulic oil via forced air, and the air and hydraulic supply/return temperatures are close, or in other words, a small differential exists, then the normal recourse is to go to water cooling or to increase the fin area of an air-cooled heat exchanger beyond what is practical.

The following arrangement describes a means for air cooling hydraulic oil when small temperature differences between oil and air exist. Referring to Figs. 1 and 2, the arrangement shows a partition for the exchangers using a hinge- spring-loaded flapper 10. During normal operation, with enough delta t (temperature differential) to provide cooling, the fan 12 pressure forces the flapper 10 open, and the entire fin area 14 is utilized for cooling by the fan. As the ambient air temperature increases such that the delta t diminishes, the thermal control 16 will sense the oil temperature rise and allow compressed air to enter via the solenoid 18, thereby closing the flapper 10. This arrangement causes the following to occur: a) A...