Link for an excavating chain and associated excavating chain

Abstract

A link for an excavating chain for a ballast excavating device below a railroad track, the link comprising a body extending longitudinally between a front end and a rear end and being crossed by at least one front through-hole and a rear through-hole configured to receive hinge means with an adjacent link of the chain, the front and rear through-holes extending along axes parallel to each other and contained in a reference plane of the body, the link further comprising, on an inner side of the body with respect to the reference plane opposite to the outer side, a concave guide surface extending over an envelope having an axis generator parallel to the axes of the link joints, the guide surface being configured to at least locally match a curvature of a return member of the excavating device.

1 . A link for an excavating chain intended to travel on a travel path having an excavating portion for a ballast excavating device below a railroad track, the link comprising; a body extending longitudinally between a front end and a rear end and being crossed by at least one front through-hole and a rear through-hole configured to receive hinge means with an adjacent link of the chain, the front and rear through-holes extending along axes parallel to each other and contained in a reference plane of the body, the link being characterized in that the body has, on an inner side of the body with respect to the reference plane, opposite to the outer side, a concave guide surface extending over an envelope having an axis generator parallel to the axes of the link, the guide surface being configured to match a curvature of a return member of the excavating device. 
     
     
         2 . The chain link of  claim 1 , wherein the guide surface extends along a guiding curve having at least partially the shape of an elliptical arc. 
     
     
         3 . The link for an excavating chain of  claim 1 , wherein the distance separating two front and rear longitudinal ends of the guide surface is greater than the distance separating the front and rear through-holes, and preferably greater than the center distance between the front and rear through-holes. 
     
     
         4 . The link for an excavating chain of  claim 1 , wherein the front and rear ends of the body each have a curved convex portion free of edges. 
     
     
         5 . The link for an excavating chain of  claim 1 , wherein the link comprises a projecting part extending from an outer side of the body with respect to the reference plane. 
     
     
         6 . The link for an excavating chain of  claim 1 , wherein the projecting part comprises a scoop for transporting ballast. 
     
     
         7 . The link for an excavating chain of  claim 6 , wherein the scoop has a stop surface configured to receive a counter-stop of an adjacent rear link of the chain so as to limit a relative rotation between the link of chain and the rear adjacent link around the axis of the rear through-hole. 
     
     
         8 . The link for an excavating chain of  claim 1 , wherein at least one of the through-holes configured to receive hinge means with an adjacent link of the chain has a flat surface so as to block an axis of the hinge means in rotation. 
     
     
         9 . The link for an excavating chain of  claim 5 , characterized in that the link has fingers born by the scoop and projecting outward from the outer side of the reference plane in the extension of the scoop, and fingers oriented along an axis inclined with respect to the reference plane, with an inclination preferably between 65° and 80°, preferably between 70 and 75°. 
     
     
         10 . The link for an excavating chain of  claim 9 , wherein the fingers are all located above a plane perpendicular to the parallel axes of the front and rear through-holes and tangent to a lower end of said scoop. 
     
     
         11 . The link for an excavating chain of  claim 1 , wherein the projecting part comprises a counter-stop configured to come into abutment against a stop surface of a scoop of a front adjacent link to limit relative rotation between the link of chain and the front adjacent link around the axis of the front through-hole. 
     
     
         12 . The link for an excavating of  claim 1 , wherein the body is in one piece, produced by foundry, with or without machining of the front and rear through-holes or the guide surface. 
     
     
         13 . An excavating chain having an excavating portion for a ballast excavating device below a railroad track, the excavating chain comprising a succession of links of chain. 
     
     
         14 . The excavating chain of  claim 13 , wherein the links of chain comprise links of the type comprising a projecting part, comprising a scoop comprising a counter-stop, or links of the type without a projecting part. 
     
     
         15 . A device for excavating or clearing ballast comprising an excavating chain, the excavating chain being guided on its travel path at least by bevel return members, the body having on an inner side of the body with respect to the reference plane, opposite to the outer side, a concave guide surface extending over an envelope having an axis generator parallel to the axes of the link, the guide surface matching, at least locally, a curvature of at least one of the return members of the excavating device. 
     
     
         16 . The chain link of  claim 2 , wherein the guide surface extends along a guiding curve having at least partially the shape of a circular arc. 
     
     
         17 . The link for an excavating chain of  claim 4 , wherein the distance separating two front and rear longitudinal ends of the guide surface is greater than the distance separating the front and rear through-holes, and greater than the center distance between the front and rear through-holes. 
     
     
         18 . The link for an excavating chain of  claim 11 , wherein the link fingers are oriented along an axis inclined with respect to the reference plane, with an inclination between 70° and 75°.