Apparatus for acquiring dump truck duty cycle data

An apparatus for use in combination with a dump truck having a frame, an elevatable dump body on the frame and a hydraulic hoist therefor, an engine having a throttle, a retarder, and a transmission having a reverse gear, to acquire as duty cycle data a measurement of the use of system components such as the drive train usage, retarder usage, reverse gear and dump cycle usage, from said truck comprising:

• ground speed sensing means associated with said truck and having an output signal;
• a plurality of sensing switches associated respectively with said engine throttle, retarder, and transmission reverse gear and producing separate output signals in the full throttle, retarder-on, and reverse-gear-on positions respectively and no signal in the part throttle, no retarder, and forward positions respectively;
• a hoist pressure switch for sensing pressure in said hydraulic hoist corresponding to a loaded dump body;
• a body position switch closed when said dump body is elevated from said frame;
• a one-shot timer switch, having an actuating circuit containing said body position switch and said hoist pressure switch in series such that said one shot-timer is activated only when a loaded dump body is raised from said frame;
• a microcomputer having an inner for receiving said ground speed signal, and inputs for each of said engine throttle, retarder, transmission and one-shot timer switches, said microcomputer being programmed to measure the time interval that said ground speed signal is within each of a plurality of finite increments corresponding to the speed range of said truck, said microcomputer further having a plurality of data memories and internal switching means responsive to the presence or absence of a signal from any of said engine, retarder, and transmission switches, and from said one-shot timer for selectively recording said time interval in each of said finite increments in a specific one of said data memories depending on a signal produced by a combination of said switches whereby each of said memories contains a histogram containing the total elapsed time of each speed increment for a given mode of operation of said truck.