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:
Mar. 14, 2000
Filed:
Mar. 24, 1998
Dipchand V Nishar, Columbus, IN (US);
Thomas A Dollmeyer, Columbus, IN (US);
Christopher R Nelson, Columbus, IN (US);
Cummins Engine Company, Inc., Columbus, IN (US);
Abstract
A system and method for air compressor control wherein the air compressor is loaded only when engine activities require it to be loaded or when free engine power is available to operate the compressor. An air compressor system is an engine-driven, piston-type compressor which operates in a loaded and an unloaded mode and provides air to a vehicle's air powered devices, such as service brakes, air suspension, windshield wipers, etc. The operating mode of the compressor is controlled by a pressure activated air governor which applies an air signal when pressure in a reservoir reaches a set level that activates a cap valve on an unloader stopping the air compressor. When the air pressure in the reservoir drops below a lower set pressure or when energy is 'free,' such as during downhill operations, the air governor exhausts the air signal allowing the air compressor to resume operation. Additionally, when the reservoir is of a pressure between the two set pressures and is in an unloaded state it will be maintained in that state for a set period of time to prevent rapid cycling of the air compressor. Further, when the reservoir is of a pressure between the two set pressures and is in a loaded state the air compressor will be unloaded after a set time interval that is based on a compressor head metal temperature to maintain threshold temperatures of the compressor head metal within a suitable range. Additionally, the compressor head is evaluated such that whenever the compressor head temperature exceeds a predetermined threshold temperature the air compressor is placed in an unloaded state until the compressor head temperature drops below the predetermined threshold temperature. The system is further capable of recording data indicative of compressor operation for detecting leaks in the air system and vehicle operator characteristics.