Caterpillar Tractor Co.

Towmotor Corporation

Walter M Shaffer

Lloyd K Heinold

John T Crawford

Victor V Virostek

James R Doyle

A power train with an auxiliary creeper drive system is disclosed which includes an engine, a primary transmission having an output shaft selectively driven by the engine, an auxiliary transmission selectively driven by the engine and operatively associated with the output shaft for driving the output shaft at a creeping rate of speed, and a clutch control arrangement for automatically disconnecting the engine from driving engagement with the output shaft when the auxiliary transmission is drivingly coupled thereto. Such auxiliary creeper drive system is particularly adaptable to the transmission of a fork lift truck.

Power train with an auxiliary creeper drive system

An ultra-narrow aisle lift truck vehicle has a body including discrete front and rear portions connected by a pair of elongated stabilizing and support members. The stabilizing and support members are movable vertically in tracks on the body portions so that they provide both structural support and integrity between the front and rear portions as well as being selectively movable into and out of a ground engaging position to perform a stabilizing function. A pair of vertical masts mounted on the front and rear portions support a vertically movable carriage assembly. The carriage assembly includes a carriage having a pair of horizontally directed forks thereon which may extend into laterally adjacent opposite sides of the vehicle and return to a position within the body and between the lateral sides thereof. The carriage is mounted on an extension pantograph and is turnable about a vertical axis by means of a motor to accommodate such lateral positioning.

Side loading ultra-narrow aisle lift truck

A power train with an auxiliary creeper drive system is disclosed which includes an engine, a primary transmission having an output shaft selectively driven by the engine an auxiliary transmission selectively driven by the engine, and operatively associated with the output shaft for driving the output shaft at a creeping rate of speed, and a clutch control arrangement for automatically disconnecting the engine from driving engagement with the output shaft when the auxiliary transmission is drivingly coupled thereto. Such auxiliary creeper drive system is particularly adaptable to the transmission of a fork lift truck.

An improved pressure sensitive valving arrangement is provided for a power steering unit for a lift truck, and in particular for a battery powered lift truck. To the conventional implement valve is added an accumulator charging means which includes an additional valve, herein called a 'blocking or control valve', which additional valve is downstream from the implement valve and which additional valve, when actuated, blocks the flow of fluid through the implement valve to thereby build up pressure for charging an accumulator. The blocking valve includes a blocking spool which operates against a pressure-actuated pilot plunger such that when the pressure in the accumulator reaches or exceeds a predetermined amount, the pilot plunger shifts the blocking spool to permit the fluid to again flow through the implement valve. The blocking spool is actuated by a force acting on a control member associated with the lift or tilt levers, or may be actuated independently by a mechanism responsive to reduced pressure in the accumulator. The pressure-responsive mechanism shifts the blocking spool to a blocking position to charge the accumulator whether or not one of the lift or tilt implement actuators has been in use and has been returned to its neutral position.

Pressure sensitive charging means for a steering system

An improved valving arrangement and actuator is provided for a power steering unit for a lift truck, and in particular for a battery powered lift truck. To the conventional implement valve is added an accumulator charging means which includes an additional valve, herein called a 'blocking valve,' which additional valve is downstream from the implement valve and which additional valve, when actuated, blocks the flow of fluid through the implement valve to thereby build up pressure for charging an accumulator. The blocking valve includes a blocking spool which operates against a pressure-actuated pilot plunger such that when the pressure in the accumulator reaches or exceeds a predetermined amount, the pilot plunger shifts the blocking spool to permit the fluid to again flow through the implement valve. The blocking spool is actuated by a force acting on a control member associated with the lift or tilt levers when said force is sufficient to overcome the retaining force provided by the reduced pressure in the accumulator acting on said pilot plunger.

Blocking valve for power steering for lift trucks

A mechanical guidance mechanism is associated with each steerable wheel of a vehicle such as a fork lift truck. The guidance mechanism has a roller guidance member positioned to contact the guide surface laterally adjacent the vehicle. The roller is rotatably mounted on a slidable C-shaped channel member which is slidably disposed over a square bar. The square bar is rigidly, pivotally affixed to the vehicle. The other free end of the bar is pivotally fixed to the first lever at one end, which first lever has a fixed axis about which it pivots substantially midway between one end and an elongated slot on the other end. A second lever having a fixed pivot substantially midway between the ends thereof has a pin rigidly fixed to a first end which traverses the slot in the first lever. The other end of said second lever has a spring rigidly mounted thereon which is mechanically linked to a third lever pivotally fixed to the vehicle intermediate the ends thereof and having a free end thereof fixed to a wheel king pin so as to transmit turning motion to a wheel. A control valve is provided for rendering the hydraulic power system normally controlling the turning motion of the wheel into an inoperative condition whereby the mechanical guidance mechanism fully controls the turning of the wheel. Thus, the mechanical guidance mechanism provides for automatic guided steering of the vehicle in narrow aisle environments which is easily converted to operator control by means of a control valve when the vehicle is taken from a narrow aisle environment.

Self-contained steering guidance means

A drive system for a vehicle includes a fluid pump which drives a fluid motor which in turn drives a variable speed transmission of the type including an input toroidal disc, an output toroidal disc, and wheel means rollingly connecting the input and output discs, with the output disc being used to drive the vehicle.

Vehicle drive

A lift truck vehicle suitable for use in ultra narrow aisle applications includes a pair of combined side frame and outrigger members interconnecting front and rear body portions of the vehicle. The combined side frame and outrigger members provide both structural integrity to the vehicle body as well as serve to stabilize the vehicle when loading and unloading loads on opposite sides of the vehicle. The combined side frame and outrigger members are generally elongated and have a pair of flanges at opposite ends thereof including shafts thereon rotatively journaled into the front and rear body portions. A linear motor interconnecting corresponding flanges of the combination side frame and outrigger members provides motive power for rotating members from their roading or travelling position away from contact with the ground support surface into their stabilizing position in contact with the ground support surface. When contacting the ground support surface, the side frame and outrigger members are conveniently low in profile so that the vehicle carriage and forks may be lowered to handle loads on common type pallets at floor level.

Outrigger and frame support member

A load handling vehicle is provided which comprises a generally elongated body having a pair of traversable masts thereon for side loading and unloading long and heavy loads. The masts are provided with articulating booms suspended from a horizontal spreader for grasping cargo containers by twist locks on their extremities. Means are provided for traversing the masts to the side of the body so that the load may be deposited thereon for travel. The body is equipped with motive power means for propelling the vehicle. Wheels at the four corners of the vehicle provide support and means for moving the vehicle sideways to the longitudinal direction of travel for picking up and depositing loads. Segments in the form of telescoping track members of the vehicle body can be extended so as to provide greater lateral stability when picking up and depositing loads. Enhanced operator visibility is provided by means of a pantograph mounted cab which is movable to various positions suited for the roading, loading and unloading modes of operation of the vehicle.

Heavy lift side loader truck

An attachment for use on a fork lift truck includes a base portion, and stabilizer bars movable relative thereto, laterally of the truck. The attachment also includes a platform movable relative to the base means laterally of the truck, and actuating means, including pulley and cable means, are utilized to initially move the stabilizer bars laterally of the truck, for engagement with a storage rack for stabilizing the fork lift truck. The platform is then shifted laterally to shift the load thereon. When this operation is completed, the platform is initially retracted, with the stabilizer bars in their outward or extended positions, and then the stabilizer bars themselves are retracted.

Side handling attachment

A hydraulic system for an electrically powered lift truck or the like supplies pressurized fluid for powering implements and for powering a hydraulic power steering system which is provided with hydraulic accumulator means for accumulating a supply of pressurized fluid for providing fluid for steering the vehicle for a predetermined period of time. A pressure-responsive charging valve is provided for maintaining a minimum amount of pressure in the accumulator and includes control means responsive to system pressure for activation and deactivation of an electric motor for powering a pump for the system.

Growing community of inventors

Peoria, IL, United States of America

Walter M Shaffer