Power and free conveyor track section
United States Patent Khondker {45} Apr. 29, 1975 [54] POWER AND FREE CONVEYOR TRACK \.876.904 9/1932 Francis |O4/94 SECTION i.92i,109 8/l933 webb et 10..... i04/95 2.875.703 3/1959 Bishop et al. I04/89 X [75] Inventor: Azlzul H. Khondker. Detroit` Mich. 3.217.658 11/1965 Dehne 104/111 x [73] Assignee: American Chain &amp; Cable Company,  
  Inc. New Yorky N Y. Prmutr)l bxmnmer-Lloyd L. King Assistant Brandner-Andres Kashnikow [22] Fled Maf- 26 |973 Attorney, Agent, or Firm-Barnes, Kisselle, Raisch &amp; [21] Appl. No.; 345,095 Choate [52] U.S. Cl. 104/94; l04/I l l; iO4/l55 [57] ABSTRACT [51] Int. Cl E01b 25/22 A Pwef and fr Conveyor ack Cnsfmo com* [5s] Field ofsearch 104/89, 91,94, 95. |06. Pfising spaced POW@r and f&#39;ee &#34;ack Sections and I04/107` 109, lll; 23S/164; 10S/154, 155 yokes extending between the track sections. Each yoke has a T-shaped cross section including a base [56] References Cited portion welded to the tracks and a transversely ex- UNITED STATES PATENTS tending portion extending from the base portion. 1,509,474 9/1924 Guilt&#34; 23S/|64 l1 Claims 8 Drawing Figures POWER AND FREE CONVEYOR TRACK SECTION This invention relates to power and free conveyors and particularly to power and free conveyor track sections.  
 BACKGROUND OF THE INVENTION In power and free conveyors. spaced tracks define power or conveyor tracks and free or carrier tracks along which the conveyor and carriers are moved. respectively. It has been common to provide longitudinally spaced yokes between the tracks for supporting one track with respect to the other.  
  A major problem with respect to such track constructions is that closely spaced vertical hangers and lateral bracings are used to provide the desired stability&#39;. Various devices have been suggested for giving further stability. For example, in U.S. Pat. No. 3.2l7,658, there is shown a construction wherein a T-section rail cap is provided on the upper or power track extending along the track. Although this may increase horizontal hanger span, lateral stability&#39; is still a factor and for heavy concentrated loads. a rail cap of excessive depth is necessary. In such cases. the rail cap functions as a deep beam of which the web and the compression flange are highly susceptible to lateral buckling. In addition, such a deep beam occupies considerable space thereby limiting head room.  
  Among the objects of the invention are to provide a power and free conveyor track section which overcomes the difficulties of the prior art; which results in a construction wherein the span between hangers may be increased; which provides greater lateral stability; which is economical and has substantial strength without limiting head room.  
 SUMMARY OF THE INVENTION In accordance with the invention. the power and free conveyor track construction comprises spaced power and free track sections and yokes extending between the track sections. Each yoke has a cross section including a base portion welded to the tracks and a transversely extending portion extending from the base portion.  
 DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a power and free conveyor system embodying the invention.  
  FIG. 2 is a fragmentary sectional view on an enlarged scale taken along the line 2-2 in FIG. l.  
  FIG. 3 is a fragmentary exploded side elevational view on an enlarged scale of a portion of the system shown in FIG. l.  
  FIG. 4 is a fragmentary side elevational view on an enlarged scale of the portion shown in FIG. 3.  
  FIG. 5 is a fragmentary side elevational view of a modified form.  
  FIG. 6 is a sectional view taken along the line 6-6 in FIG. 5.  
  FIGA 7 is a view similar to FIG. 4 showing a modified form of the invention.  
  FIG. 8 is a view similar to FIG. 7 showing a further modified form of the invention.  
 DESCRIPTION Referring to the drawings, the power and free conveyor track construction comprises a power track l0 comprising an l-beam along which wheel trolleys l l of a conveyor l2 are moved and a free or carrier track I3 comprising inwardly spaced channels 14 on which wheel carriers C are supported so that the pusher l5 on a conveyor 12 engages a pusher dog 16 on the carriers C in accordance with well-known constructions. Carriers C comprise one or more trolleys for supporting a load bar L.  
  U-shaped yokes 17 are provided at longitudinally spaced points between the track sections l0, 13, and at certain points. the yokes 17 are supported by bolts on vertical support members 18 fixed on the superstructure of the building.  
  Each power track I0 comprises a top horizontal flange 19 and bottom horizontal flange 20 connected by a vertical web 21. Each free track channel 14 comprises a base 22 and inwardly&#39; extending horizontal flanges 23, 24.  
  Each yoke 17 has a T-cross section including a base portion 25 extending longitudinally of the tracks and a transverse portion 26 extending outwardly&#39; and transversely ofthe base portion and the tracks. The yokes 17 may be made in one piece or from several pieces welded together. Thus, the base portion 25 may cornprise one metal piece and the transverse portion may comprise another metal piece welded to the base portion 25.  
  The base portion 25 of each yoke 17 is welded to the top flange 19 of the track l0 as at 27. The base portion of each yoke 17 is also welded to the bases 22 of the channels 14 as at 28.  
  Adjacent track sections are connected to one another in a suitable manner. As shown in FIGS. 3 and 4, adjacent tracks 10 and adjacent tracks I3 are brought into abutment within a yoke 17 on one track section and plates 29. 30, 3l are welded to the horizontal flanges of the tracks (FIG. 4).  
  ln the modified form shown in FIGS. 5 and 6, the tracks l2&#39;` I3&#39; extend beyond the yokes nearest the end of each track section and abut outside the yokes. Plates 32, 33, 34 and 35 are welded to the horizontal flanges of the tracks and plates 35u are welded to the webs 14 of track 13&#39; to form the joint.  
  In each of the forms described` in use. the cross section of the yoke and the manner in which it is welded to the tracks strengthen the track section. The con struction provides a resistance to rotation in both lon gitudinal and lateral directions thereby reducing the vertical deflection of the track and the consequent moments and stresses in the conveyor track structure. The resultant track produces the advantages of a long span track.  
  It has been found that, in use. the reinforcing members substantially strengthen the track section by stiffening the ends and there is a considerable reduction in the deflection, shear and flexural stresses in all the members.  
  The power and free track construction embodying the invention results in carrying proportionate flexural and shear loads, based on relative flexural and rigidity moduli, to its fullest stress capacity. Accordingly. the design is most economical in the use of steel in the superstructure hanger steel. floor supports, if used. and the conveyor proper. In addition to increasing the flexural and shear rigidities in the vertical and longitudinal directions, respectively, added strength is achieved in the lateral direction. This furnishes increased lateral 3 stability and eliminates the necessity&#39; of closely spaced lateral bracing as heretofore required. Since there are no portions which project outwardly from the conveyor proper, head room is not adversely&#39; affected In the form of the invention shown in FIG. 7. the tracks l0. 14 are supported by&#39; a yoke 40 made of two sections 4l. each of which has a base portion 42 welded to the tracks l` 14 and a transverse portion 43. Adjacent transverse portions are fastened together by bolts 44. Welds 45 also connect portions 43.  
  In the form of the invention shown in FIG. 8, the tracks l0. I4 are supported by a yoke 50 having a U- shaped cross section including base portion 5l welded to the tracks l0. I4 and transverse portions S2.  
 l claim:  
  l. ln a power and free conveyor track section. the combination comprising a power track along which a conveyor is adapted to be moved.  
 a free track for supporting carrier beneath the con vey&#39;or.  
 longitudinally spaced yokes extending between said tracks.  
 each said yoke having a cross section that includes a base portion extending longitudinally and a transverse portion extending transversely&#39; outwardly&#39; from the basc portion,  
 said base portion having free edges.  
 said power track comprising a horizontal portion engaged by said base portion of said yoke to which said base portion of said yoke structure is welded along said free edges.  
 said free track including a vertical portion to which the base portion is welded along its free edges.  
 2. The combination set forth in claim l wherein said cross section of said yoke comprises a T-section.  
  3. The combination set forth in claim l wherein said cross section of said yoke comprises a U-section.  
  4. The combination set forth in claim l wherein said yoke comprises two angle sections connected to form a T`section.  
  5. The combination set forth in claim l wherein said power track section comprises an I cross section and said free track section comprises inwardly facing spaced channels.  
  6. ln a power and free conveyor track section. the combination comprising a power track comprising an I cross section along which a conveyor is adapted to be moved.  
 said track comprising vertically&#39; spaced top and bottom flanges connected by a vertical web.  
 a free track comprising inwardly&#39; facing channels for supporting carriers beneath the conveyor.  
 each said channel comprising a base and inwardly extending flanges` longitudinally spaced U-shaped yokes extending between said tracks` each said yoke having a T cross section comprising a base portion extending longitudinally&#39; and engaging substantiallyl the entire width of said top flange of said power track and engaging substantially the entire width of said base of said free track.  
 said base portion having free edges.  
 said base portion being welded along said free edges to said top flange of said power track and said base of said free track.  
  7. The combination set forth in claim 6 wherein said yoke portions are integrally&#39; formed.  
  8. In a power and free convey&#39;or track section, the combination comprising a plurality of track sections, each track section comprising a power track comprising an l cross section along which a conveyor is adapted to be moved.  
 said track comprising vertically&#39; spaced top and bottom flanges connected by a vertical web` a free track comprising inwardly&#39; facing channels for supporting carriers beneath the conveyor.  
 each said channel comprising a base and inwardly extending flanges.  
 longitudinally&#39; spaced U-shaped yokes extending between said tracks.  
 each said yoke having a T cross section comprising a base portion extending longitudinally and engaging substantially the entire width of said top flange of said power track and engaging substantially the entire width of said base of said free track.  
 said base portion having free edges.  
 said base portion being welded along said free edges to said top flange of said power track and said base of said free track,  
 and means joining said track sections.  
  9. The combination set forth in claim 8 wherein the power tracks and free tracks of adjacent track sections abut, said means joining said track sections comprising plates welded to and extending between the tracks.  
  l0. The combination set forth in claim 9 wherein said tracks abut within a yoke.  
  ll. The combination set forth in claim 9 wherein said tracks extend beyond a yoke and abut exteriorly&#39; of a yoke.