Quick Touch Clam Control for Mining Shovel

Abstract

An improved clam control mechanism for a mining shovel may offer reduced operator fatigue during excavation operations involving the simultaneous and repetitive manipulation of joysticks and switches. The control mechanism may be configured for the loading and unloading of a shovel having a clam rotatable above the shovel, and may include at least two joysticks adapted for a variety of tasks including fore and aft movements, and angular rotation of the shovel. At least one switch may be adapted for moving the clam automatically between fully open and fully closed positions, such that when the switch is briefly pressed a first way, the clam automatically fully opens, and when a switch is briefly pressed a second way, the clam automatically fully closes. On the other hand, if the switch is briefly pressed during either automatic opening or closing of the clam, any movement of the clam may be immediately halted.

What is claimed is: 
     
         1 . A work machine including a shovel adapted for excavating material, the work machine comprising:
 a main body affixed to and adapted to swivel about a movable base, the main body including an operator cab and a boom moveably secured to the main body, and wherein one end of the boom is vertically movable relative to the main body;   the main body further including a stick, wherein one end of the stick is aftwardly and rearwardly movably attached to the other end of the boom, and wherein the shovel is vertically rotatably secured to the stick at an opposite end of the stick;   the main body further including a movable clam secured to the shovel, the clam being positioned above the shovel and adapted to swivel between open and closed positions over the shovel;   a control system configured for loading and unloading the shovel, the control system including a plurality of joysticks, each configured for predetermined directional movements, each movement adapted for cyclic positioning of the shovel;   the control system further configured for moving the clam automatically between fully open and fully closed positions, the control system including at least one switch adapted to be briefly pressed a first way to cause the clam to automatically and fully open, and to be briefly pressed a second way to cause the clam to automatically and fully close;   wherein if the switch is briefly pressed either way at any time during either automatic opening or closing of the clam, operation of the clam is immediately halted.   
     
     
         2 . The work machine of  claim 1 , further comprising a separate apparatus for changing speeds of any automatic clam movements between open and closed clam positions. 
     
     
         3 . The work machine of  claim 1 , further comprising a first directional joystick movement adapted for angularly positioning the main body relative to the moveable base, and a second directional joystick movement adapted for raising and lowering the boom. 
     
     
         4 . The work machine of  claim 3 , further comprising a third directional joystick movement adapted for controlling forward and aft movements of the stick, and a fourth directional joystick movement adapted for controlling vertically oriented, angular rotation of the shovel. 
     
     
         5 . The work machine of  claim 3 , wherein the first and second directional joystick movements are configured to be carried out by a first joystick. 
     
     
         6 . The work machine of  claim 4 , wherein the third and fourth directional joystick movements are configured to be carried out by a second joystick. 
     
     
         7 . The work machine of  claim 1 , further comprising at least one hydraulic cylinder actuator configured for moving the clam relative to the shovel, and wherein the actuator includes a ramp-down feature. 
     
     
         8 . The work machine of  claim 7 , wherein the ramp-down feature includes at least one proximity sensor. 
     
     
         9 . The work machine of  claim 1 , wherein the at least one switch is a two-way rocker switch configured for opening and closing the clam. 
     
     
         10 . A control system for a machine having a main body and a base including tracks, the main body being adapted to swivel horizontally and angularly relative to the base, the main body including an operator cab and a boom vertically movable relative to the main body; the main body further including a stick movably attached to the boom at a first end of the boom, and having a shovel vertically rotatably secured to the stick at a second end of the boom; the main body further including a movable clam secured to the shovel, the clam being positioned above the shovel, the clam adapted to swivel between open and closed positions over the shovel;
 wherein the control system is configured for loading and unloading the shovel, the control system including a plurality of joysticks, each configured for predetermined directional movements, each movement adapted for cyclic positioning of the shovel, the control system further including at least one switch adapted for moving the clam automatically between fully open and fully closed positions, such that when a switch is briefly pressed a first way, the clam automatically fully opens, and when a switch is briefly pressed a second way, the clam automatically fully closes;   wherein if the switch is briefly pressed either way at any time during either automatic opening or closing of the clam, operation of the clam is immediately halted.   
     
     
         11 . The control system of  claim 10 , further comprising a separate apparatus for changing speeds of any automatic clam movements between open and closed clam positions. 
     
     
         12 . The control system of  claim 10 , further comprising a first directional joystick movement adapted for angularly positioning the main body relative to the moveable base, and a second directional joystick movement adapted for raising and lowering the boom. 
     
     
         13 . The control system of  claim 12 , further comprising a third directional joystick movement adapted for controlling forward and aft movements of the stick, and a fourth directional joystick movement adapted for controlling vertically oriented, angular rotation of the shovel. 
     
     
         14 . The control system of  claim 12 , wherein the first and second directional joystick movements are configured to be carried out by a first joystick. 
     
     
         15 . The control system of  claim 13 , wherein the third and fourth directional joystick movements are configured to be carried out by a second joystick. 
     
     
         16 . The control system of  claim 10 , further comprising at least one hydraulic cylinder actuator configured for moving the clam relative to the shovel, and wherein the actuator includes a ramp-down feature. 
     
     
         17 . The control system of  claim 16 , wherein the ramp-down feature includes at least one proximity sensor. 
     
     
         18 . The control system of  claim 10 , wherein the at least one switch is a two-way rocker switch configured for opening and closing the clam. 
     
     
         19 . A method for providing a quick touch clam control for a work machine having a shovel clam, comprising:
 providing a CPU, a plurality of joysticks, and a plurality of switches, and configuring the CPU to interface with the joysticks and switches through respective joystick and clam switch bus interfaces;   providing a system of signals to be generated from the joysticks in accordance with directional joystick movements, and having the signals read by the CPU through the joystick bus interface;   providing a system of signals to be generated from the switches in accordance with selective switch movements, and having the signals correspondingly read by the CPU through the switch bus interface;   configuring the switches to control a shovel clam;   
       wherein the shovel clam may be either automatically fully opened or fully closed by briefly touching an open or a close switch, respectively. 
     
     
         20 . The method of  claim 19 , wherein if the switch is briefly pressed at any time during either automatic opening or closing of the clam, operation of the clam is immediately halted.