Patents Assigned to Lull Engineering Company, Inc.
  • Patent number: 4683802
    Abstract: A load self-leveling system for a vehicle utilizing hydraulic cylinders to operate a telescopic lifting boom and a material handling carriage. The system includes a pair of fluid flow dividers interposed between the source of hydraulic fluid under pressure and the hydraulic cylinders operating the boom and carriage. The flow dividers are structured to direct a greater flow of hydraulic fluid to the boom cylinder and a lesser flow to the carriage cylinder, the precise numeric proportions of flow division being engineered to best suit a particular vehicle, combined with the specific componentry of that vehicle. In addition to the flow dividers, the system includes reversible flow piloted check valves, override control including override relief valves to allow independent adjustments, and matched cylinder area ratios. A compact assembly housing various of the components comprising the system is disclosed.
    Type: Grant
    Filed: March 15, 1984
    Date of Patent: August 4, 1987
    Assignee: Lull Engineering Company, Inc.
    Inventors: James A. Prokop, David C. Truehart
  • Patent number: 4336720
    Abstract: A sensing system for a load carrying vehicle having a hydraulically controlled load carrier which is subjected to cantilever loading such that tipping of the vehicle may occur. The vehicle includes a load bearing frame and an axle supporting that frame. The frame is mounted through a sub-frame assembly so as to be separable to a limited degree from the axle. The initiation of this separation signals the dangerous load condition. A load sensing device disposed between the axle and the sub-frame assembly detects the initiation of separation of the sub-frame from the axle. The sensor functions as a mechanically actuated relief valve in the hydraulic system by which cantilever loading is accomplished. Flow of hydraulic fluid from the sensing device functions to prevent further extension of the load which could induce tipping. Details of the sub-frame assembly and sensing device are disclosed.
    Type: Grant
    Filed: August 22, 1980
    Date of Patent: June 29, 1982
    Assignee: Lull Engineering Company, Inc.
    Inventor: James A. Prokop
  • Patent number: 4147263
    Abstract: A versatile mobile high lift loader characterized by an extendible telescopic boom carried by a longitudinally extendible transfer carriage. The transfer carriage travels on stepped fore and aft longitudinal transfer rails for greater operator visibility. The transfer rails are stepped laterally to provide for maximum width of the operator compartment and to permit the use of dual front wheels. The transfer carriage and boom extension travel on cam roller non-friction bearings for cycling demands of the fork lift transferring boom. The transfer rails include readily replaceable hardened wear surfaces on a unitized frame. The loader includes modular drive train fabrication for less expensive manufacturing cost and easier servicing. It is provided with drive line disc brakes and locking differential for easy servicing, non-power assist and positive braking with and without load. The telescoping boom includes a novel hose reel assembly for transfer of internal hosing within the boom.
    Type: Grant
    Filed: January 6, 1977
    Date of Patent: April 3, 1979
    Assignee: Lull Engineering Company, Inc.
    Inventors: Sherman B. Frederick, Ernst A. Dahlquist