Safety device and construction machine

Abstract

A safety device includes a contour sensor which acquires contour data representing a contour of a landform around a hydraulic excavator; a determination part which determines, based on the contour data, whether the landform satisfies an execution criterion of executing a turning-over prevention control for preventing the hydraulic excavator from being turned over to a slope extending in a specific direction therearound; and a lowering control part which lowers a leading end of a working device to the slope when the determination part determines that the execution criterion is satisfied.

1 . A safety device for ensuring a safety of a construction machine including a machine body and a working device attached to the machine body, the safety device comprising:
 an acquisition part which acquires contour data representing a contour of a landform around the construction machine;   a determination part which determines, based on the contour data, whether the landform satisfies an execution criterion of executing a turning-over prevention control for preventing the construction machine from being turned over to a slope extending in a specific direction around the construction machine; and   a lowering control part which lowers a leading end of the working device to the slope when the determination part determines that the execution criterion is satisfied.   
     
     
         2 . The safety device according to  claim 1 , wherein
 the determination part calculates, based on the contour data, an inclination angle of the slope to a ground surface on which the construction machine stands, and determines that the execution criterion is satisfied when the inclination angle is larger than a threshold.   
     
     
         3 . The safety device according to  claim 1 , wherein
 the determination part calculates, based on the contour data, an inclination angle of the slope to a ground surface on which the construction machine stands, determines whether the construction machine is in an unstable state, and determines that the execution criterion is satisfied when the inclination angle is larger than a threshold and determining that the construction machine is in the unstable state.   
     
     
         4 . The safety device according to  claim 3 , wherein
 the determination part acquires an acceleration rate of the construction machine, and determines that the construction machine is in the unstable state when the acquired acceleration rate is higher than a threshold.   
     
     
         5 . The safety device according to  claim 1 , wherein
 the lowering control part lowers the leading end of the working device to the slope along a route having a shortest distance between the leading end of the working device and the slope.   
     
     
         6 . The safety device according to  claim 1 , wherein
 the lowering control part lowers the leading end of the working device to a target position which makes a distance between a position of the leading end of the working device and a specific position of the slope be within a predetermined range.   
     
     
         7 . The safety device according to  claim 6 , wherein
 the target position is at a position where the leading end of the working device is below the surface of the slope.   
     
     
         8 . The safety device according to  claim 6 , wherein
 when the determination part determines that the execution criterion is satisfied, the lowering control part lowers the leading end of the working device to the slope while hindering a manipulation of an operator, and allows the manipulation of the operator after finishing the lowering of the leading end of the working device to the target position.   
     
     
         9 . A construction machine comprising:
 the safety device according to  claim 1 ;   a machine body; and   a working device attached to the machine body.