Tensioning mechanism for feeder conveyor positioned within feeder housing

#The structure disclosed in this patent application is similar to that disclosed in copending patent application of Roger D. Hanaway and Larry R. James for Feeder Idler Drum Shaft with Removable Extensions Ser. No. 283,975, filed July 16, 1981.

#This invention relates to a tensioning mechanism for the idler roller of a feeder chain of an agricultural harvester.

#Harvester endless belt conveyors with floating idler rollers having belt tensioning mechanisms using compression springs disposed outside the conveyor housing side walls are show in U.S. Pat. Nos. 3,854,572; 3,804,231; and 2,302,656. U.S. Pat. Nos. 3,521,433 and 3,537,243 each show a pair of arms within an endless belt conveyor housing for supporting a conveyor idler roller for limited vertical swinging movement about a transverse horizontal axis. In these last-mentioned patents, the tensioning of the endless belt conveyor is effected in part by screw adjusters on the outside of the conveyor housing which are connected to pivot pins for the arms, which pivot pins extend through longitudinal slots in the side walls of the conveyor housing. Compression spring-type tensioning mechanisms for harvester conveyor idlers positioned on the laterally inner sides of the conveyor side walls are shown in U.S. Pat. No. 1,634,187 and 2,612,988.

#The invention is illustrated in the drawings in which:

#FIG. 1 is a side view of an agricultural combine;

#FIG. 2 is an enlarged side view of a portion of the feeder conveyor with parts broken to show parts of a tensioning mechanism;

#Referring to FIG. 1, the combine 11 incorporating the present invention includes a main frame 12 on which an engine 13 is mounted for powering the combine and driving a pair of front wheels 14, 15 through a drive train (not shown). The rear of the main frame 12 is supported by a pair of rear steerable wheels 16, 17. A detachable crop header 21 is releasably secured to a feeder housing 22 as by a hook joint 23 and the rear end of the feeder housing is pivotally mounted to the main frame 12 on a transverse pivot axis 24. The crop material entering the header 21 is conveyed by oppositely flighted sections of a transverse auger 26 to a central portion thereof where retractable fingers 27 move the material rearwardly to a feeder conveyor 28 within the feeder housing 22. A second or rear endless belt conveyor 29 accepts material from the front feeder conveyor 28 and feeds it rearwardly to an axial flow combine processor 31 mounted on a transverse axis 32 within a processing chamber 33 at the rear of a grain tank 34. An operator's enclosure or station 36 is mounted at the front of the grain tank 34 in a position overlying the feeder housing 22. The header 21 is raised and lowered about transverse axis 24 by a pair of laterally spaced hydraulic actuators 38, only one of which is shown, disposed between the combine main frame 12 and the feeder housing 22.

#Referring to FIGS. 1, 2 and 3, the feeder housing 22 includes a pair of laterally spaced side walls 41, 42 and top and bottom walls 43, 44. Mounted within the feeder housing 22 are an upper drive shaft 46 rotating on pivot axis 24 and a lower floating idler or idler drum 47. The upper drive shaft 46 is driven by the engine 13 through a drive train, not shown. The endless belt feeder conveyor 28 is of the chain belt-type and includes conveyor chains 51, 52 carried by the shaft 46 and the drum 47. A series of transverse slats 53 are attached to the chains 51, 52 which move in the direction of arrow 54 to convey crop material. The idler drum 47 is floatingly mounted relative the side walls 41, 42 of the feeder housing 22 by a pair of shaft supporting tensioning mechanisms 56, 57 which are opposite images of one another. The idler drum 47 is rotatably mounted on a transverse axis 58 by a nonrotating shaft 59. The drum is rotatably supported by a pair of anti-friction bearings 61, 62 on the laterally opposite ends of a main or central shaft portion 63. The central portion 63 of the shaft 59 also carries a pair of retainers 73 for the idler drum support bearings 61, 62.

#The central shaft portion 63 terminates at its opposite ends within the lateral space between the side walls 41, 42 of the feeder housing 22 and within the lateral spacing of a pair of tensioning support arms 66, 67 of the tensioning mechanism 56, 57. A pair of axial extensions 68, 69 are mounted on laterally opposite ends of the central portion 63 of the shaft 59 by cap screws 71. As shown in FIGS. 3 and 5, the inboard parts 74, 75 of the extensions 68, 69 extend through openings 76, 77 in the free ends of the support arms 66, 67 and outboard parts 78, 79 of the arms 66, 67 are in vertically confronting abuttable relation to upper and lower stops 81, 82 adjustably positioned on the outboard sides of the side walls 41, 42 of the feeder housing 22. The shaft extensions 68, 69 at their inboard ends extend through aligned openings in a pair of dust shields 83, 84 interposed between the arms 66, 67 and the side walls 41, 42 of the feeder housing. The dust shields 83, 84 are in covering relation to a pair of relatively large openings 86, 87 in the side walls 41, 42. The openings 86, 87 permit the ends 68, 69 of the idler shaft 59 to move vertically in response to movement of the forward end of the conveyor 28 as varying loads are encountered and also permits the idler shaft to move longitudinally under the influence of the tensioning mechanisms 56, 57 as for instance when wear occurs in the feeder chains 51, 52.