Load release height control system for excavators

Abstract

An excavator includes a dipper assembly configured to receive a dipper load, the dipper assembly having an actuated position for emptying the dipper load, a sensor assembly configured to monitor one or more operating conditions of the excavator, and a control module. The control module is configured to receive signals from the sensor assembly, determine a height of the dipper assembly relative to a surface, and inhibit movement of the dipper assembly to the actuated position.

What is claimed is: 
     
         1 . An excavator, comprising:
 a dipper assembly configured to receive a dipper load, the dipper assembly having an actuated position for emptying the dipper load;   a sensor assembly configured to monitor one or more operating conditions of the excavator; and   a control module configured to:
 receive signals from the sensor assembly; 
 determine a height of the dipper assembly relative to a surface; and 
 inhibit movement of the dipper assembly to the actuated position. 
   
     
     
         2 . The excavator of  claim 1 , wherein the control module is programmed to prevent movement of the dipper assembly to the actuated position when the height of the dipper assembly relative to the surface is greater than a dipper height limit. 
     
     
         3 . The excavator of  claim 2 , wherein the one or more operating conditions of the excavator comprise the height of the dipper assembly relative to the surface. 
     
     
         4 . The excavator of  claim 3 , wherein the control module is programmed to calculate the dipper height limit at least in part from the signals received from the sensor assembly. 
     
     
         5 . The excavator of  claim 2 , wherein the sensor assembly is configured to monitor a weight of the dipper load, and the control module is programmed to calculate the dipper height limit at least partly based on the weight of the dipper load. 
     
     
         6 . The excavator of  claim 1 , wherein the control module is programmed to calculate the height of the dipper assembly relative to the surface based at least in part on the signals received from the sensor assembly. 
     
     
         7 . The excavator of  claim 2 , wherein the control module is configured to provide a warning to an operator of the excavator when the height of the dipper assembly relative to the surface is greater than the dipper height limit. 
     
     
         8 . The excavator of  claim 2 , wherein the control module is configured to control the dipper assembly, the control module being programmed to automatically lower the height of the dipper assembly to a position below the dipper height limit before allowing the dipper assembly to move to the actuated position. 
     
     
         9 . The excavator of  claim 1 , wherein the sensor assembly comprises a laser sensor configured to measure a distance relative to the dipper assembly. 
     
     
         10 . The excavator of  claim 1 , wherein the sensor assembly comprises a laser scanner configured to build a three-dimensional map of an area surrounding the dipper assembly. 
     
     
         11 . The excavator of  claim 1 , wherein the sensor assembly comprises an infrared sensor configured to measure a distance relative to the dipper assembly. 
     
     
         12 . A mining shovel, comprising:
 a dipper configured to receive a dipper load, the dipper having an open dipper bottom;   a dipper door coupled to the dipper, the dipper door having a first position for covering the open dipper bottom and a second position for emptying the dipper load;   a sensor assembly configured to monitor a height of the dipper relative to a surface; and   a control module configured to receive signals from the sensor assembly, and to control the movement of the dipper door between the first and second positions.   
     
     
         13 . The mining shovel of  claim 12 , wherein the control module is programmed to prevent movement of the dipper door from the first position to the second position when the height of the dipper relative to the surface is greater than a dipper height limit. 
     
     
         14 . The mining shovel of  claim 13 , wherein the sensor assembly is configured to monitor one or more operating conditions of the mining shovel. 
     
     
         15 . The mining shovel of  claim 14 , wherein the control module is programmed to calculate the dipper height limit at least in part from the signals received from the sensor assembly. 
     
     
         16 . The mining shovel of  claim 13 , wherein the control module is configured to slow movement of the dipper door from the first position to the second position when the height of the dipper relative to the surface is greater than the dipper height limit. 
     
     
         17 . The mining shovel of  claim 13 , wherein the control module is configured to control the dipper, the control module being programmed to automatically lower the height of the dipper to a position below the dipper height limit before allowing the dipper door to move to the second position. 
     
     
         18 . A control system for a dipper assembly having an actuated position for emptying a dipper load, the control system comprising:
 a sensor assembly configured to:
 monitor a height of the dipper assembly relative to a surface; and 
 monitor a weight of the dipper load; 
   a control module configured to:
 receive signals from the sensor assembly; 
 calculate a dipper height limit based on the signals; and 
 inhibit movement of the dipper assembly to the actuated position when the dipper assembly is above the dipper height limit. 
   
     
     
         19 . The control system of  claim 18 , wherein the control module is configured to create a response when the height of the dipper assembly relative to the surface is greater than the dipper height limit. 
     
     
         20 . The control system of  claim 18 , wherein the control module is configured to control the dipper assembly, the control module being programmed to automatically lower the height of the dipper assembly to a position below the dipper height limit before allowing the dipper assembly to move to the actuated position.