Allis-chalmers Corporation

Benonie C Ehrhardt

Dean A Matthews

Walter A Pivarunas

An improved structural arrangement for mechanically and hydraulically interconnecting a cluster of three hydraulic cylinders of the hydraulic jacks associated with the load carriage elevating and mast structure elevating functions of a forklift truck. The clustered cylinders include a centrally located 'secondary' cylinder and two oppositely disposed 'primary' cylinders symmetrically positioned contiguous to the centrally located secondary cylinder. Each cylinder has a corresponding attachment block rigidly secured thereto, each attachment block being provided with a hydraulic passage therethrough which communicates with an aligned hydraulic passage through the wall of its corresponding cylinder. An interconnecting block having an internal hydraulic manifold and outlet ports which are adapted to be aligned with the hydraulic passages of the respective attachment blocks and corresponding hydraulic passages through the walls of the respective cylinders, and thus to hydraulically communicate with the interior of the respective cylinders, is adapted to be bolted to the attachment blocks of the respective cylinders. An important feature of the construction is the 'shear ledge' construction for supporting the structural load on the interconnecting block to relieve the shear load on the bolts which secure the interconnecting block to the attachment blocks of the respective hydraulic cylinders. In accordance with this shear ledge construction the interconnecting block is provided with a welded plate defining an overhanging shoulder which seats on the upper surface of the attachment block of the centrally located secondary cylinder, and the attachment blocks of the oppositely disposed primary cylinders are recessed to define oppositely disposed shoulders which seat on the upper surface of the interconnecting block.

Mechanical and hydraulic interconnection for clustered hydraulic

A triple section mast for a lift truck is disclosed in which a single pulley carries two hydraulic supply hoses in one on top of the other relationship thereby minimizing lateral space occupied by the hoses and maximizing the visibility through the mast. The three-stage mast utilizes one single acting hydraulic lift jack extending between the intermediate and inner mast sections and a pair of short single acting hydraulic jacks mounted on the inner mast section with pistons supporting pulleys about which carriage support chains are trained and connected to the carriage on the inner mast section. A hose pulley is supported on each short jack piston in oblique relation to the chain pulley so that the two hoses trained over each hose pulley pass downwardly to the carriage on the laterally inner sides of the chains and pass downwardly at the rear of the short jacks on the laterally outer sides of the carriage support chains where they are connected to two manifolds mounted on the inner mast section. Two pairs of hoses are connected to the manifolds on the inner mast section and are trained one on top of the other around pulleys on the bottom of the intermediate mast section and thence upwardly to a pair of manifolds near the top of the outer mast section. The hose pulleys at the bottom of the intermediate mast section are mounted on a pair of stub axles which also support a pair of load pulleys carrying chains extending between the inner mast section and the outer mast section.

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Park Forest, IL, United States of America

Benonie C Ehrhardt