Cab supporting structure

Abstract

To provide a cab supporting structure capable of supplying a protection function with a simple configuration by using an attenuation mechanism commonly used for a controlled vehicle for protecting the cab or an operator from high impact force acting on the cab while absorbing vibration and shock on the cab in a normal condition when a construction machine falls down. The cab supporting structure is provided with an attenuation mechanism elastically supporting a cab against a vehicle frame. A regulation member, only when certain displacement is generated in the cab in the extension direction of the attenuation mechanism, regulating this displacement is provided separately from this attenuation mechanism. The regulation member regulates the displacement of the cab before a stroke end of the attenuation mechanism. Upon arranging an operation machine on the vehicle frame, the regulation member is provided at least at the opposite side of the operation machine.

1 . A cab supporting structure supporting a cab against a vehicle frame via an attenuation mechanism, 
 wherein a regulation member, only when certain displacement is generated in the cab in the extension direction of the attenuation mechanism, regulating this displacement is provided separately from this attenuation mechanism.    
     
     
         2 . The cab supporting structure according to  claim 1 , 
 wherein said regulation member has a cab side member attached to the cab side, and this cab side member is in a non-interferential relation with said vehicle frame side in a normal condition.    
     
     
         3 . The cab supporting structure according to  claim 1  or  claim 2 , 
 wherein said regulation member regulates displacement of the cab before a stroke end of said attenuation mechanism.  
 
     
     
         4 . The cab supporting structure according to  claim 1  or  2 , 
 wherein said regulation member is arranged between a column of the cab and the vehicle frame.  
 
     
     
         5 . The cab supporting structure according to  claim 1  or  2 , 
 wherein said regulation member is provided at least at the opposite side of an operation machine when the operation machine is arranged on said vehicle frame.  
 
     
     
         6 . The cab supporting structure according to  claim 1  or  2 , 
 wherein, when rigidity of said cab is set to be larger at the rear side than at the front side, said regulation member is provided at least at the rear side of the cab.