Navistar International Transportation Corporation

Riley A Thomas, Iii

Brian P Marshall

Eric T Swenson

Ronald L Blanchard

An electronic circuit for providing a momentary switch closure function output in response to operation of a control-request switch input to a closed condition and maintenance of the control-request switch input in closed condition for an amount of time greater than the time of the momentary switch closure function output. One use of the invention is as a single switch PTO enabler in conjunction with an electronically controlled internal combustion engine to provide a required momentary switch closure input to the engine electronic control for enabling the engine speed to change to a demanded speed.

Single switch PTO enabler

Multiple control-request switches are operatively coupled by an electronic interlock circuit with an electronic engine control that controls an engine that powers a heavy duty automotive vehicle. The vehicle is also equipped with one or more devices, such as an air-compressor or hydraulic pump, that are powered from the engine via a power take-off. The control-request switches request control of this equipment from various stations via control of an operational function of the engine, such as control of engine speed. The interlock circuit functions to allow only a first-to-be-actuated of the control-request switches to acquire control so that subsequent actuation of any other switch causes the control to go to a default mode to avoid conflicting control of the engine and equipment powered through a power take-off.

Growing community of inventors

Oakbrook Terrace, IL, United States of America

Riley A Thomas, Iii