Abstract: A mobile lift device having a load moving device capable of engaging a load is provided. The mobile lift device includes one or more systems for stabilizing the mobile lift device during operation of the load moving device. According to one exemplary embodiment, the mobile lift device is a heavy duty wrecker having a rotatable boom assembly. The heavy duty wrecker comprises a monitoring system for stabilizing the wrecker during operation of the boom assembly. The monitoring system comprises a plurality of sensors and a monitoring circuit coupled to the sensors to generate a force signal representative of at least one force being applied to the wrecker based upon the transmitted signals.

Abstract: A mobile lift device having a load moving device capable of engaging a load is provided. The mobile lift device includes one or more systems for stabilizing the mobile lift device during operation of the load moving device. According to one exemplary embodiment, the mobile lift device is a heavy duty wrecker having a rotatable boom assembly. The heavy duty wrecker comprises a monitoring system for stabilizing the wrecker during operation of the boom assembly. The monitoring system comprises a plurality of sensors and a monitoring circuit coupled to the sensors to generate a force signal representative of at least one force being applied to the wrecker based upon the transmitted signals.

Abstract: A mobile lift device having a load moving device capable of engaging a load is provided. The mobile lift device includes one or more systems for stabilizing the mobile lift device during operation of the load moving device. According to one exemplary embodiment, the mobile lift device is a heavy duty wrecker having a rotatable boom assembly. The heavy duty wrecker comprises a monitoring system for stabilizing the wrecker during operation of the boom assembly. The monitoring system comprises a plurality of sensors and a monitoring circuit coupled to the sensors to generate a force signal representative of at least one force being applied to the wrecker based upon the transmitted signals.

Abstract: A mobile lift device having a load moving device capable of engaging a load is provided. The mobile lift device includes one or more systems for stabilizing the mobile lift device during operation of the load moving device. According to one exemplary embodiment, the mobile lift device is a heavy duty wrecker having a rotatable boom assembly. The heavy duty wrecker comprises a monitoring system for stabilizing the wrecker during operation of the boom assembly. The monitoring system comprises a plurality of sensors and a monitoring circuit coupled to the sensors to generate a force signal representative of at least one force being applied to the wrecker based upon the transmitted signals.

Abstract: To resist side deflection and buckling of the top and side plates in larger size multi-section telescopic crane booms, top plate lateral supports for the movable boom sections in the fully extended and fully retracted critical zones are provided to supplement the action of bottom lateral wear pads. The top plate lateral supports include adjustable spring bars on the sides and forward ends of the boom sections and coacting cam pads on the top plates of the boom sections at their forward ends and in the socketing zones when the boom sections are fully extended.

Abstract: The pivot shaft for the boom of a large mobile construction crane is located near the upper side of the boom base section and its opposite ends are journaled in heavy bearings mounted on vertical side supports rising from a boom turntable. To lock the boom to the boom pivot shaft for unison rotation in the pivot shaft bearings, a single locking pin is received through registering openings in the pivot shaft and a surrounding hub or pillow block fixed to the boom structure within the confines of an internal box support. A screw-threaded extension on the locking pin engages a nut on the exterior of the boom base section, the nut being floatingly constrained by fixed guide tracks which prevent nut rotation with the threaded locking pin while allowing limited lateral and angular adjustment of the locking pin.

Abstract: A pair of safety stop blocks are welded to opposite sides of the fly section of a construction crane boom. The stop blocks have slide passages to receive the branches of a boom extension or load cable which is looped around an arcuate saddle near the base of the fly section. A pair of stop buttons are swaged to the extension cable branches between the saddle and the two stop blocks and are normally spaced somewhat from the stop blocks to allow the cable to seek an equal loading position around the saddle. The stop blocks carry cable retainer elements near the tops of the slide passages to prevent the escape of the cable therefrom. Should the extension cable fail in any region thereof under load, at least one swaged stop button will be engaged by a stop block of the boom fly section to positively arrest its retractive movement before any damage can occur.

Abstract: A means to maintain the upper wear pads in a multisection telescopic crane boom in contact with the side plates of the circumscribing boom section to reduce the transverse bending moment on the top plate of the boom section, thus reducing the stress thereon, and allowing the use of a thinner top plate so as to provide a lighter and less costly boom structure.