Roller extension slide

Abstract

A roller extension slide including first and second track beams, a center beam of box section with wheels projecting through clearance openings of lateral webs engaging track surfaces of the track beams; guide flanges of the center beam engaging guide slots of the track beams for maintaining the track beams closely spaced; and the travel slot formed in each track beam. Center wheel axle extensions engage opposite ends of travel slots in the track beams for limiting the travel between retracted and extended positions of the track beams, with track beam wheel engagement spacing being at least 80% of the track length the first position and at least 40% in the second position, an extension distance being at least 80% percent of the track length, the first position being with the apparatus substantially contained within the track length. Also disclosed is a table incorporating a pair of the extension slides.

1 . A roller extension apparatus comprising:
 (a) elongate first and second track beams, each track beam having parallel-spaced facing track surfaces;   (b) an elongate center beam;   (c) a longitudinally spaced plurality of wheels rotatably mounted on the center beam for rolling engagement with the track surfaces of the first and second track beams; and   (d) means for maintaining the parallel spaced relation of the track beams,   wherein each of the track beams has track beam wheel engagement at a spacing of not less than 60 percent of a track length of that track beam in a first relative longitudinal position of the track beams and not less than 30 percent of the track length in a second position of the track beams, an extension distance between the first and second positions being not less than 80 percent of the track length.   
   
   
       2 . The apparatus of  claim 1 , further comprising means for limiting travel of the rolling engagement between the relative longitudinal first and second positions of the track beams. 
   
   
       3 . The apparatus of  claim 2 , wherein the means for limiting travel comprises a longitudinal travel slot being formed in each track beam, and respective wheel axle extensions projecting from the center beam engaging opposite ends of the travel slots. 
   
   
       4 . The apparatus of  claim 1 , wherein the track beams and the center beam are of equal length, the first relative position being with the apparatus substantially contained within the track length. 
   
   
       5 . The apparatus of  claim 1 , wherein the means for maintaining the parallel spaced relation of the track beams comprises:
 (a) each track beam having a longitudinal guide slot formed therein; and   (b) the center beam having a plurality of guide flanges for slidably engaging the guide slots of corresponding track beams.   
   
   
       6 . The apparatus of  claim 5 , wherein each of the guide flanges is one of an oppositely facing pair of flange portions, and the guide slot of each track member is one of a facing pair of guide slots. 
   
   
       7 . The apparatus of  claim 6 , wherein the guide flanges engage the guide slots at locations spaced apart on each track beam not less than half of the corresponding track length. 
   
   
       8 . The apparatus of  claim 6 , wherein the center beam comprises a main portion having a pair of parallel-spaced side webs connected by parallel-spaced lateral webs, the wheels being mounted between the side webs and projecting through clearance openings formed in the lateral webs, the oppositely extending guide flanges being coplanar extensions of the side webs. 
   
   
       9 . The apparatus of  claim 1 , wherein each track beam comprises a main portion of generally C-shaped cross-section including a pair of parallel-spaced track flanges forming the track surfaces, and a connecting web. 
   
   
       10 . The apparatus of  claim 9 , each track beam further comprising a mounting flange extending from the connecting web opposite one of the track flanges in generally coplanar relation thereto. 
   
   
       11 . The apparatus of  claim 1 , further comprising a longitudinally spaced plurality of axles mounted to the center beam, each axle supporting an independently rotatable pair of the wheels, each of the wheels being located between the track surfaces of a corresponding one of the track beams. 
   
   
       12 . The apparatus of  claim 11 , wherein the axles are mounted proximate opposite ends thereof to the center beam. 
   
   
       13 . The apparatus of  claim 1 , wherein at least some of the wheels comprise an outer resilient member for cushioned contact with the track surfaces of the track beam. 
   
   
       14 . The apparatus of  claim 13 , wherein the outer resilient member is a rubber )-ring. 
   
   
       15 . A table comprising the apparatus of  claim 1  in combination with a first panel member being mounted to the first track beam and a second panel member mounted to the second track beam in coplanar relation to the first article, the articles being in edgewise proximity in the first relative position of the track beams and being spaced apart in the second relative position of the track beams. 
   
   
       16 . The apparatus of  claim 15 , comprising a parallel spaced pair of the apparatus of  claim 1  correspondingly connected between the first and second panel members. 
   
   
       17 . A roller extension apparatus comprising:
 (a) elongate first and second track beams, each track beam having parallel-spaced facing track surfaces and comprising a main portion of generally C-shaped cross-section including a pair of parallel-spaced track flanges forming the track surfaces, and a connecting web;   (b) an elongate center beam comprising a pair of parallel-spaced side webs connected by parallel-spaced lateral webs;   (c) a longitudinally spaced plurality of wheels rotatably mounted between the side webs and projecting through clearance openings formed in the lateral webs of the center beam for rolling engagement with the track surfaces of the first and second track beams;   (d) means for maintaining the track beams in a predetermined parallel-spaced relation during the rolling engagement, comprising:
 (i) each track beam having a longitudinal guide slot formed therein; and 
 (ii) the center beam having a plurality of guide flanges for slidably engaging the guide slots of corresponding track beams; and 
   (e) means for limiting travel of the rolling engagement between the relative longitudinal first and second positions of the track beams, comprising a longitudinal travel slot being formed in each track beam, and respective wheel axle extensions projecting from the center beam engaging opposite ends of the travel slots,
 wherein each of the track beams has track beam engagement at a spacing of not less than 80 percent of a track length of that track beam in a first relative longitudinal position of the track beams and not less than 40 percent of the track length in a second position of the track beams, an extension distance between the first and second positions being not less than 80 percent of the track length, and 
 wherein the track beams and the center beam are of equal length, the first relative position being with the apparatus substantially contained within the track length. 
   
   
   
       18 . The apparatus of  claim 17 , wherein each of the guide flanges is one of an oppositely facing pair of flange portions, and the guide slot of each track member is one of a facing pair of guide slots, and the oppositely extending guide flanges are coplanar extensions of the side webs of the center beam.