The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 03, 1989
Filed:
Jan. 27, 1987
Charles D Orth, Cedarburg, WI (US);
Richard C Barthel, Harwood Heights, IL (US);
Peter J Malone, Rosemont, IL (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A refrigeration control system for cooling a vehicle passenger compartment having a compressor/pump for circulating refrigerant between an evaporator located for cooling the compartment air and a condenser located for ambient heat exchange. An expansion valve controls refrigerant flow from the condenser to the evaporator; and, a first thermistor senses directly the temperature of the refrigerant on the high pressure inlet side of the valve and a second thermistor senses refrigerant flow temperature on the low pressure discharge side of the valve. A microprocessor compares the first thermistor output with predetermined first upper and lower values and effects opening and closing of the compressor clutch switch for high pressure cut-off; and, a fan switch is opened and closed for energization and de-energization of a condenser cooling fan. The output of the second thermistor is compared with a second set of upper and lower limit values for responding to normal service duty cycling of the clutch; and, the microprocessor is effective upon sensing a predetermined temperature after an elapsed time interval to open the clutch switch in the event of low or insufficient refrigerant charge.