Abstract: Apparatus for towing and hoisting vehicles to be serviced is described. Concepts and techniques for enabling effective capability under varied conditions of terrain and footing are discussed. Specific apparatus described combines an extendable boom which is rotatable about a center post and lateral stabilizers on the truck afterbody. Top and bottom rollers on the base tube of the boom guide the outreach arm of the boom to a retracted position around a hydraulic actuator within the base tube. Side mounted actuators rotate the boom about the center post.

Abstract: An upright including upper and lower end portions is provided and support structure is carried by the lower end portion of the upright for support of the latter from one end of a vehicle. A boom including base and free end portions has its base end portion pivotally supported from the upper end portion of the upright for oscillation relative thereto about a horizontal axis extending transversely of the upright and the boom, and motor structure is operably connected between the upright and the base end portion of the boom for oscillating the boom relative to the upright. The support structure on a first disclosed form of the invention is operative to utilize the boom mounting structure of a backhoe for support of the upright from a backhoe vehicle in lieu of the backhoe boom and the support structure on a second form of the invention includes a hitch frame for removably supporting the upright from the three-point hitch of a tractor.

Abstract: A telescopic boom is pivotally mounted on a frame of a vehicle and comprises telescopically disposed first, second, third and fourth sections. A double-acting cylinder has a rod thereof connected to the first section and a housing thereof connected to the second section. A first pulley is rotatably mounted on a forward end of the cylinder housing and a second pulley, having a larger diameter than the first pulley, is rotatably mounted on a rearward end of the cylinder housing. A first end of a cable is secured to the first section and is sequentially entrained over the first pulley, secured to the third section, entrained over the second pulley and has a second end thereof secured to a forward end of the first section. Thus, extension of the cylinder will function to extend the second section relative to the first section and simultaneously extend the third section at twice the linear speed as that of the second section.

Abstract: An articulated boom crane, constructed to allow convenient conversion to straight boom crane operation, and having a secondary boom that has adjustably extensible members supporting a boom tip assembly and that can be selectively coupled to a main boom either in an articulated crane configuration or in a straight boom crane configuration. In the disclosed embodiments, this selective coupling is effected by means of sets of attachment plates fixed to the secondary boom which allow either end portion of the boom to be attached to a pair of side plates pivotally connected to the main boom. Centering posts on the secondary boom aid in aligning the side plates and attachment plates, and tapered pins are engaged through holes in the plates, to provide their secure coupling. When the crane is in the straight boom configuration, stop plates on the side plate prevent movement of the secondary boom with respect to the main boom as a result of load forces.