Abstract: A steering system for a tracked machine having dual power paths to opposed planetary differential gear sets for providing conventional differential steering and a second method of steering where the speed of one track is reduced while keeping the other track at its initial speed. The steering system includes primary and secondary drive inputs into the opposed planetary gear sets. The planetary gear sets combine the rotations from the primary and secondary drive inputs in a first steering mode for increasing the speed of one track while reducing the speed of the other track by an equal amount. A second mode of steering is also possible where the speed of one track is reduced while keeping the other track at its initial speed for larger turning radii. The primary drive input includes a variable displacement fluid pump and a variable displacement motor connected to the planetary gear sets by means of a drive shaft for driving the tracks of the machine.

Abstract: A locking member is disclosed that is selectively operable to secure the loader boom arms in a raised position for service or repair. The locking member is pivotally connected to a boom arm for movement to an operative position between the boom arm and its respective lift cylinder where it is restrained in compression between the boom arm and lift cylinder to latch the boom arm in a raised position against collapsing movement. The locking member includes a pair of spaced apart, parallel, and aligned mounting plates, each being generally in the form of a right triangle and a generally U-shaped yoke fixed between the mounting plates and extending along opposed corresponding sides of the mounting plates for a part of their length.

Abstract: A linkage arrangement is disclosed for connecting a dozer blade and pushbeams which reduces blade roll-back during lifting thereby making it substantially more difficult for dirt and the like to cling to the blade. The linkage arrangement includes a pair of leveling link assemblies which are mounted to the pushbeams on opposite sides of the tractor frame. An adjustable strut is connected between one of the leveling link assemblies and the upper edge of the blade, and a tilt cylinder is connected between the upper edge of the blade and the opposed leveling link assembly. As the blade is raised, the adjustable strut and corresponding leveling link assembly automatically force the blade into a relatively vertical attitude thereby reducing blade roll-back. Actuation of the tilt cylinder permits the blade to be tilted while the blade is being kept at the vertical attitude established by the leveling link assembly and adjustable strut.

Abstract: The blade of an earthworking vehicle is mounted to pushbeams by pivotal L-shaped hinge body connections permitting pivotal movement of the blade about a transverse horizontal axis in the body of the blade. The hinge connections are retained on the forward end of each pushbeam. The connections have a hinge pin leg disposed parallel to the plane of the blade, in the body of the blade, and another leg secured to the forward end of the pushbeam. In the preferred embodiment, the longitudinal axis of the hinge pin leg is disposed inside the body of the blade, between the face and rear wall, thereby reducing the torsional load on the blade and stabilizing the blade. More open space is provided between the tracks and the rear of the blade which reduces the possibility of debris build-up.

Abstract: A method and apparatus are disclosed for mechanically steering vehicles such as crawler tractors and the like or skid steer tractors, which include a pair of independently operable power sources. The apparatus includes a pair of independent first linkage systems interconnected between a single operator control lever and each respective power source to achieve equivalent power outputs from the sources upon movement of the lever. A pair of independent second linkage systems are interconnected between respective links in the first linkage system and respective throttling means. In the method, each throttling means may be operated independently of the other to achieve unequal power outputs from the two sources by virtue of the independent first and second linkage systems.

Abstract: A linkage system for pivotally supporting a boom on a vehicle body with a material handling unit pivoted on the outer end of the boom through a unit fluid ram is disclosed herein. The linkage system consists of an arm that is supported for pivotal movement on the vehicle body with the boom pivoted on the arm at a spaced location. Linkage means interconnect the arm and the boom and the unit fluid ram is pivotally connected to the linkage means. The boom and body have cooperating guide means that guides the movement of the arm between first and second positions so that the moment arm is at a minimum when the boom extends generally parallel to the terrain.