Extendible axle member for the rear of an agricultural harvester

An extendible axle member (146, 148) for an agricultural harvester (100), the harvester having a chassis (107) supported on two driven front wheels (120) and two driven and steerable rear wheels (124), the rear wheels (124) being supported on a rear axle assembly (128) that includes a central axle member (136) supported to pivot about a horizontal and longitudinally extending axis (138), the central axle member (136) including left side and right side outer axle members (142, 144), the extendible axle member (146, 148) comprising:

• an elongate telescopic portion (400) having a longitudinal axis parallel to the longitudinal extent of the elongate telescopic portion (400), the elongate telescopic portion (400) further having a plurality of bearing surfaces (252, 254, 334, 336), the elongate telescopic portion (400) having a first end and a second end, wherein the first end is configured to be slidably received inside a first open end (410) of the left or right side outer axle member (142, 144) and to be telescopically supported on bearing surfaces (248, 250, 322, 324) disposed inside the left or right side outer axle member (142, 144);
• a C-frame (402), comprising a vertical member (404) to which the elongate telescopic portion (400) is fixed, the vertical member (404) having an upper end and a bottom end, a first horizontal member (406) fixed to and extending horizontally from the upper end, and a second horizontal member (408) fixed to and extending horizontally from the bottom end, the two horizontal members (406, 408) defining upper and lower steering knuckle mounts (178, 176),
• wherein the C-frame (402) and the elongate telescopic portion (400) are formed integral with each other and abut each other;
• and
• wherein the elongate telescopic portion is generally rectangular in shape, the rectangle being defined by a vertically oriented front wall, a vertically oriented rear wall, a horizontally oriented top wall and a horizontally oriented bottom wall, and wherein each of the plurality of bearing surfaces is disposed at respective corners of the elongate telescopic portion and said each of the plurality of bearing surfaces is spaced apart from the other bearing surfaces of the plurality of bearing surfaces, and further wherein diagonally opposed bearing surfaces of said plurality of bearing surfaces are disposed with respect to each other such that lines of action of the forces acting on said diagonally opposed surfaces are offset from each other.