Off-highway machines, such as large wheel loaders and large mining trucks, are used to transfer material from one place to another. The material is carried in a load-body, or manipulated and/or carried by an implement of the machine. Depending on the particular functions performed by the machine and a desire for improved visibility for the operator over the work area and the material being moved, an operator station of the machine may be located at a height that is substantially elevated above the work surface over which the machine will travel and operate. In some cases, the sheer size of the machines necessitates the operator stations being located high above the work surface.
The elevated operator stations require the machines to be equipped with combinations of stairways, walkways and ladders allowing the operators and maintenance workers to climb up to and climb down from the operator stations. Due to safety concerns, the machines are further equipped with guardrails on the outboard sides of the stairways and walkways to prevent operators of the machines and maintenance workers from falling off the machines. Some known guardrail configurations for machines use an all-tube construction where vertical posts and horizontal rails are made from hollow closed-channel circular tubes. At locations of the guardrails where the vertical posts and horizontal rails intersect, one or both of the intersecting components may be modified or formed so that the components can mate and be connected to each other, typically with welds. In alternative configurations, the horizontal rails may be cut to length to be connected between adjacent vertical posts. In some implementations, guardrails are mounted to outward sides of the walkways or stairways, with mounting brackets being used to attach the lower ends of the vertical posts to the outward side. In other implementations, it may be desirable to mount components to the guardrails, such as hinges and locks for gates, and lights to illuminate the walkways or stairways. Typically, additional mounting brackets are necessary for connecting the components to the vertical posts or the horizontal rails.
USPTO Backgrounds
USPTO Backgrounds