Pin assembly for track roller bogie of track-type drive system

Abstract

A track roller bogie is pivotally supported by a pin assembly, in which a spacer for receiving a thrust load is abolished and the thrust load is supported by outer rings of the pin assembly themselves. It makes possible to assemble a pin assembly easier and to elongate a service life of the track bogie.

1 . A pin assembly for a track roller bogie of a track-type drive system, comprising: 
 a pin having a lubricant charging hole and a lubricant delivering hole delivering the lubricant from the lubricant charging hole to an outer peripheral portion in an inner portion thereof;    a first ring having a contact surface with said pin in one end so as to be firmly attached to the pin and having an outer diameter D 1 ;    a second ring brought into contact with another end side of said first ring in an axial direction of the pin so as to be rotatably pivoted to the pin and having an outer diameter D 2 ; and    a third ring brought into contact with another end side of said second ring in an axial direction of the pin so as to be firmly attached to the pin and having an outer diameter D 3 ,    wherein a part of a ring end surface contacted among said first, second and third rings has an annular recess portion, and said annular recess portion consists of a sealing means between rings for sealing therebetween, and said outer diameters D 1 , D 2  and D 3  have a relation D 1 <D 2 <D 3 .    
   
   
       2 . A track-type drive system comprising: 
 a track roller bogie having a track frame, an idler, a sprocket, a carrier roller and a track roller and pivoted to said track frame; and    a crawler belt wound around them,    wherein the track roller bogie is pivoted to the track frame by the pin assembly as claimed in  claim 1 .    
   
   
       3 . A track-type drive system comprising: 
 a track roller bogie having a track frame, an idler, a sprocket, a carrier roller and a track roller and pivoted to said track frame; and    a crawler belt wound around them,    wherein said track roller bogie is constituted by a first bogie link pivoted to the track frame, and a second bogie link pivoted to said first bogie link and to which the track roller is mounted, and    wherein said second bogie link is pivoted to said first bogie link by the pin assembly as claimed in  claim 1 .    
   
   
       4 . The pin assembly according to  claim 1 , wherein the slide portion among said first ring, said second ring and said third ring is constituted by a slide contact surface with which each of the rings is directly contacted, and a seal surface of said sealing means in correspondence to each of the slide contact surfaces, and said slide contact surface and the seal surface form a substantially one flat plane in a radial direction.  
   
   
       5 . A track-type drive system comprising: 
 a track roller bogie having a track frame, an idler, a sprocket, a carrier roller and a track roller and pivoted to said track frame; and    a crawler belt wound around them,    wherein the track roller bogie is pivoted to the track frame by the pin assembly as claimed in  claim 4 .    
   
   
       6 . A track-type drive system comprising: 
 a track roller bogie having a track frame, an idler, a sprocket, a carrier roller and a track roller and pivoted to said track frame; and    a crawler belt wound around them,    wherein said track roller bogie is constituted by a first bogie link pivoted to the track frame, and a second bogie link pivoted to said first bogie link and to which the track roller is mounted, and    wherein said second bogie link is pivoted to said first bogie link by the pin assembly as claimed in  claim 4.