Gardner-denver Company

Richard L Ertel

Robert A Litteken

Stephen A Thompson

Soren E Edstrom

Robert A Brink

A portable air compressor unit includes a sound attenuating enclosure formed to have a first compartment through which cooling air flows before passing through side-by-side mounted heat exchangers for engine coolant and compressor injection liquid. Engine and compressor inlet air filters are disposed in the first compartment. An engine driven fan draws cooling air from the first compartment into a second compartment containing the engine and compressor. An engine inlet air silencer and exhaust gas muffler are also disposed in the second compartment. Heated cooling air is discharged from the second compartment into three side-by-side ducts at the end of the enclosure opposite the first compartment. Exhaust openings in the end and side walls of the enclosure provide for final exit of the cooling air from the enclosure above the level at which cooling air enters the first compartment.

Enclosed compressor unit

A positive displacement rotary compressor is in circuit with a closable chamber disposed upstream of the compressor gas inlet and including a conduit operable to be placed in communication with the compressor discharge conduit. A control circuit is operable to sense compressor discharge pressure and at a predetermined pressure condition sequentially operate valves to shut off compressor inlet flow thereby evacuating the chamber and then placing the compressor discharge port in communication with the chamber. The compressor thereby runs unloaded or at idle at a greatly reduced inlet and discharge pressure. The operation of unloading the compressor may be controlled by sensing the chamber vacuum or by the use of time delay devices.

Growing community of inventors

Quincy, IL, United States of America

Richard L Ertel