Patent ID: 8498787
Filing Date: 2013-07-30
Classification: E02F

Abstract:
1. A monitor system for an electric cable shovel, said electric cable shovel having a shovel body mounted for rotation on a base, a boom extending upward from said shovel body and connected at its lower end to said body, a pulley mounted on the upper end of the boom, a dipper bucket suspended from the boom by a dipper cable extending over the pulley, a winch mounted on the shovel body and secured to the dipper cable, said winch including a winch drum and an electric motor for winding and unwinding said dipper cable on said winch drum so as to raise and lower said dipper bucket, a dipper arm secured to said dipper bucket and supported by an arm mechanism for moving said arm toward and away from said body of the shovel, comprising: an inclinometer mounted on said dipper arm for providing an output indicative of the inclination of said dipper arm, a current sensor for sensing the level of the electrical current supplied to said electric motor, and a monitor circuit for determining when the current sensor provides an indication of a current level in excess of a digging current threshold level for a period of time in excess of a predetermined period, and during such period of time said inclinometer indicates that said inclination of said dipper arm is below a digging threshold inclination, said monitor providing an output indicating that said shovel has completed a digging operation, filling the dipper bucket with material.