Excavator

Abstract

Described is an excavator comprising an articulated boom and a balancing mechanism at least partially assisting a movement of the boom from a lower position to an upper position by applying a pulling force on said boom.

1 . An evacuator comprising
 an articulated boom;   a balancing mechanism at least partially assisting a movement of the articulated boom from a lower position to an upper position by applying a pulling force on the articulated boom.   
     
     
         2 . The evacuator according to  claim 1 , wherein the balancing mechanism comprises a balancing member configured and arranged for generating an assisting force and a force transfer mechanism indirectly and force-transmittingly coupling the balancing member with the articulated boom. 
     
     
         3 . The evacuator according to  claim 2 , wherein the force transfer mechanism comprises a flexible link, the flexible link being a wire rope or chain. 
     
     
         4 . The evacuator according to  claim 3 , wherein the balancing member is coupled to the flexible link at a coupling portion of the flexible link, so that a direction of a force generated by the balancing member is aligned or parallel with an extension direction of the flexible link in the coupling portion. 
     
     
         5 . The evacuator according to  claim 3 , wherein the force transfer mechanism comprises a transmission. 
     
     
         6 . The evacuator according to  claim 5 , wherein the transmission comprises a cone-shaped pulley and wherein the flexible link is guided around the cone-shaped pulley in an axially offset manner. 
     
     
         7 . The evacuator according to  claim 3 , wherein the force transfer mechanism comprises a coupling device for transferring a force from the flexible link to the articulated boom such that an assisting moment assisting the movement of the articulated boom is generated on the articulated boom. 
     
     
         8 . The evacuator according to  claim 7 , wherein the coupling device is structured such that a force introduced into the coupling device by the flexible link is transferred to the articulated boom at a fixed ratio independent from the position of the articulated boom. 
     
     
         9 . The evacuator according to  claim 7 , wherein the coupling device is structured such that a force introduced into the coupling device by the flexible link is transferred to the articulated boom with a varying ratio, the varying ratio changing according to the position of the articulated boom. 
     
     
         10 . The evacuator according to  claim 7 , wherein
 the coupling device comprises a force transfer device fixedly coupled to the articulated boom such that the force transfer device and the articulated boom are integrally movable,   the force transfer device comprising a peripheral surface configured and arranged for guiding the flexible link at a predetermined distance from a hinge portion at which the articulated boom is articulated, and wherein   the flexible link is coupled to the force transfer device such that a portion of the flexible link contacts a predetermined section of the peripheral surface when the articulated boom is in a lower position.   
     
     
         11 . The evacuator according to  claim 10 , wherein the peripheral surface is at least partially curved and at least partially comprises the shape of a circular arc. 
     
     
         12 . The evacuator according to  claim 11 , wherein a center axis of the force transfer device is aligned with a rotational axis of the articulated boom in the hinge portion. 
     
     
         13 . The evacuator according to  claim 2 , wherein the balancing member is a counter weight. 
     
     
         14 . The evacuator according to  claim 2 , wherein the balancing member is a pressure cylinder. 
     
     
         15 . The evacuator according to  claim 2 , wherein the force transfer mechanism comprises rigid links. 
     
     
         16 . The evacuator according to  claim 4 , wherein the force transfer mechanism comprises a transmission. 
     
     
         17 . The evacuator according to  claim 4 , wherein the force transfer mechanism comprises a coupling device for transferring a force from the flexible link to the articulated boom such that an assisting moment assisting the movement of the articulated boom is generated on the articulated boom. 
     
     
         18 . The evacuator according to  claim 8 , wherein the coupling device comprises a force transfer device fixedly coupled to the articulated boom such that the force transfer device and the articulated boom are integrally movable, the force transfer device comprising a peripheral surface configured and arranged for guiding the flexible link at a predetermined distance from a hinge portion at which the articulated boom is articulated, and wherein the flexible link is coupled to the force transfer device such that a portion of the flexible link contacts a predetermined section of the peripheral surface when the articulated boom is in a lower position. 
     
     
         19 . An evacuator comprising;
 an articulated boom;   a balancing mechanism at least partially assisting a movement of the articulated boom from a lower position to an upper position by applying a pulling force on the articulated boom; and   wherein the force transfer mechanism comprises a transmission; and   wherein the transmission comprises a cone-shaped pulley and wherein the flexible link is guided around the cone-shaped pulley in an axially offset manner.   
     
     
         20 . An evacuator comprising;
 an articulated boom;   a balancing mechanism at least partially assisting a movement of the articulated boom from a lower position to an upper position by applying a pulling force on the articulated boom; and   wherein the coupling device is structured such that a force introduced into the coupling device by the flexible link is transferred to the articulated boom with a varying ratio, the varying ratio changing according to the position of the articulated boom.