Patent Application
20100314908
The present invention relates to a cab frame structure for vehicles such as large agricultural tractors, and more specifically to a beltline member for a cab frame structure which is capable of providing roll-over protective (ROP).
A cab frame structure is shown in U.S. Pat. No. 6,543,840, issued in April 2003 to Collier et al. However, it appears that this cab frame structure does not include a ROPs sufficient beltline or beltline level support member between the rear corner posts, since the patent does not show any gusseting between a beltline level support member and the rear corner posts.
Large agricultural tractors have cab frames which are designed to perform as roll-over protective structures or ROPS. In such structures the beltline area requires a lot of support between the rear corner posts due to the significant loads being transferred from the upper portion of the cab frame to the cab mounting structure. The cab frame must meet force, energy, and zone of clearance constraints. The beltline support has proven to be crucial when meeting these specifications and has required additional bracing and gussets to achieve the desired stiffness and support. Some previous production designs have required as many as seven to eight beltline parts to meet design requirements. It is desired to have a simpler yet robust beltline support design.
Accordingly, an object of this invention is to provide a simple yet robust beltline support for a ROPs cab frame.
A further object of the invention is to provide such a ROPs beltline support which creates more room in the cab interior.
These and other objects are achieved by the present invention, wherein a beltline support member is formed by two separate parts which are welded together. The support member includes a central portion, a left end fixed to the left rear corner post and a right end fixed to the right rear corner post. The central portion is curved or offset to the rear to allow for more room in the interior of the cab. The offset allows the seat to mover farther rearward, between the rear corner posts, thus creating a larger space for the operator.
The first part includes a midportion, a left flange portion and a right flange portion. The midportion has a C-shaped cross sectional shape. The midportion of the first part has a wider upper side, a back plate and a narrower lower side. The second part includes an elongated midportion and left and right flanges which are attached to the front side of the rear corner posts. The midportion has a first edge which engages an inner surface of the first part, and has a side surface which engages an edge of the first part.
Referring to
Each of the rear corner posts 16 and 18 are formed from a tube which is bent or curved to define lower portions 20a and 20b, slanted transition portions 22a and 22b and upper portions 24a and 24b. Lower portions 20a and 20b are positioned at the rear of the cab inwards of the rear wheel fenders 30a and 30b. The slanted transition portions 22a and 22b are between the lower portions 20a and 20b and the upper portions 24a and 24b.
Transition portions 22a and 22b are joined together by a beltline or waist level member 32. Beltline member 32 includes a ROPS-capable rear beltline member 34 and a front beltline member 36 which are welded together, and which are welded to the respective transition portions. Rear beltline member 34 includes a central portion 38, a left flange 40 and a right flange 42. As best seen in
Front beltline member 36 includes a central portion 50, a left flange 52 and a right flange 54. As best seen in
As best seen in
The flanges 40, 42, 52 and 54 form gussets between the rear corner posts and the beltline member parts 32 and 36. The result is a two-piece, rear, ROPS-capable beltline support for an agricultural tractor cab. This support provides sufficient structural support to the beltline region of the cab frame that is needed for ROPS certification, while at the same time significantly reducing the overall part count to achieve this functionality. The beltline member also includes a rearward offset between the cab rear corner posts. This rearward offset increases the amount of room available to the operator inside of the cab.
While the present invention has been described in conjunction with a specific embodiment, it is understood that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, this invention is intended to embrace all such alternatives, modifications and variations which fall within the spirit and scope of the appended claims.
