Personal loader

Abstract

A three or four wheeled miniature personal loader device driven by an engine or motor and provided with a powered drive unit having a simplified hydrostatic differential which allows the device to turn quickly within its own wheel base. The personal loader is provided with a front pair of drive wheels and a pair of rear steerable wheels or a single rear steerable wheel. The loader may be provided with the rear wheel or wheels being directly steered via known steering linkages and power assist steering mechanisms or in the alternative either a single or pair of castor type wheels which are not directly steered but are indirectly steerable by the operators manual maneuvering of the loader. The engine is also connected a hydraulic pump for providing appropriate regulation of a hydraulic system operating the hydraulically controlled loader mechanisms. An operator walking or standing behind the machine and within reach of the control handle may control the vehicle speed and steering as well as the hydraulic system mechanism manipulation via a series of manual controls on a control handle.

Wherefore, I/we claim:  
     
         1 . A personal loader for assisting an operator in materials handling tasks comprising: 
 a frame supported by at least three wheels, at least one of the wheels being a powered drive wheel and at least one of said other wheels being a steerable wheel;    an engine supported on the frame for driving a hydraulic pump and the at least one powered drive wheel;    a hydraulic control regulating the hydraulic pump actuation of at least a first hydraulic circuit powering a vertically moveable primary accessory control means and a second hydraulic circuit providing angular rotational capability to a secondary accessory control means; and    a control handle for steering the loader, the control handle having manual actuatable inputs for operation of the hydraulic control and the at least one powered drive wheel.    
     
     
         2 . The personal loader as set forth in  claim 1  wherein the at least one powered drive wheel is a pair of fixed position drive wheels, each of the pair of drive wheels being driven by an associated first and second wheel motor which may be one of individually braked and driven relative to the other wheel motor.  
     
     
         3 . The personal loader as set forth in  claim 1  wherein the at least one powered drive wheel is a pair of fixed position drive wheels connected to the engine via a hydrostatic differential transmission and the at least one steerable wheel is a castor which is freely rotatable about a horizontal axis to facilitate conventional circumferential ground surface engagement and also freely rotatable about a vertical axis about which the at least one steerable wheel vertically rotates relative to the fixed position drive wheels.  
     
     
         4 . The personal loader as set forth in  claim 3  further comprising an accessory attachment mechanism supported and manipulated by the primary accessory control means and the secondary accessory control means, the accessory attachment mechanism being capable of coupling with a variety of different accessories for performing different material handling tasks.  
     
     
         5 . The personal loader as set forth in  claim 3  wherein the at least one steerable wheel comprises a first and second steerable rear wheels.  
     
     
         6 . The personal loader as set forth in  claim 1  wherein the control handle is directly connected to the at least one steerable wheel by a steering linkage.  
     
     
         7 . The personal loader as set forth in  claim 4  wherein the pair of drive wheels are front wheels and the at least one steerable wheel is a rear wheel and the center of mass of the loader is horizontally located between the pair of front drive wheels and the at least one rear steerable wheel.  
     
     
         8 . The personal loader as set forth in  claim 7  wherein the primary accessory control means is a pair of front loader arms each having a first end attached to the frame at a main pivot point and a second free ends supporting the accessory attachment mechanism.  
     
     
         9 . The personal loader as set forth in  claim 8  wherein the secondary accessory control means is a mechanical linkage substantially supported at the free end of each front loader arm providing angular rotation to the accessory attachment mechanism.  
     
     
         10 . The personal loader as set forth in  claim 8  wherein the main pivot point for the pair of front loader arms is located horizontally between the front drive wheels and the at least one rear steerable wheel.  
     
     
         11 . The personal loader as set forth in  claim 10  wherein any load applied to the accessory attachment mechanism is horizontally maintained forward of the front drive wheels to establish a fulcrum point defined by a rotational axis of the front drive wheels between the applied load and the center of mass of the loader about the front drive wheels.  
     
     
         12 . The personal loader as set forth in  claim 11  wherein the control handle is provided with at least a manual throttle for drive control over the front drive wheels and separate manual control devices for regulating the first hydraulic and the second hydraulic.  
     
     
         13 . The personal loader as set forth in  claim 12  wherein the hydraulic control regulates the hydraulic pump actuating an auxiliary hydraulic for powering an accessory drive motor of a loader accessory.  
     
     
         14 . The personal loader as set forth in  claim 13  wherein the control handle is further provided with an auxiliary hydraulic control device providing the operator with manual control over the accessory drive motor.  
     
     
         15 . The personal loader as set forth in  claim 14  wherein the hydraulic control regulates the hydraulic pump actuating a self leveling function for maintaining a secondary pivot axis defined by the free ends of the loader arms substantially level with respect to a horizon line.  
     
     
         16 . A manually steerable loader having a hydraulic system for controlling a loader mechanism provided with a universal attachment device for coupling with a plurality of different accessories for assisting an operator in a multitude of different materials handling tasks, the manually steerable loader comprising: 
 a frame supported by a pair of powered drive wheels and at least one steerable wheel;    an engine supported on the frame for driving a hydraulic pump and the pair of powered drive wheels;    a hydraulic control regulating the hydraulic pump actuation of a first hydraulic circuit powering a vertically moveable primary accessory control means and a second hydraulic circuit providing angular rotational capability to a secondary accessory control means;    a control handle having manual actuatable inputs for providing hydraulic control of the hydraulic pump actuation of the first hydraulic and the second hydraulic and control over the steerable wheel and the powered drive wheel; and    wherein said first hydraulic circuit regulates vertical lifting and lowering capability of a pair of loader arms pivotably attached to the frame, said second hydraulic circuit angularly regulates an accessory attachment mechanism supported by the loader arms.    
     
     
         17 . The personal loader as set forth in  claim 16  wherein the pair of powered drive wheels is a pair of fixed position drive wheels and the at least one steerable wheel is a castor which is freely rotatable about a horizontal axis to facilitate conventional circumferential ground surface engagement and also freely rotatable about a vertical axis about which the at least one steerable wheel vertically rotates relative to the fixed position drive wheels.  
     
     
         18 . The personal loader as set forth in  claim 17  wherein the control handle is immovably fixed to the frame of the loader and the operator turns the loader in a desired direction by manually maneuvering the loader frame about a wheel base defined by the pair of drive wheels and relative vertical angulation of the at least one castor wheel relative to the pair of drive wheels.  
     
     
         19 . The personal loader as set forth in  claim 18  wherein the drive wheels are provided as the front wheels of the loader.  
     
     
         20 . A method of controlling a personal loader mechanism provided with a universal attachment device for coupling with a plurality of different accessories for assisting an operator in a multitude of different materials handling tasks, the manually steerable loader comprising the steps of: 
 supporting a frame with a pair of powered drive wheels and at least one steerable wheel;    providing an engine supported on the frame for driving a hydraulic pump and the pair of powered drive wheels;    regulating the hydraulic pump actuation of a first hydraulic circuit powering a vertically moveable primary accessory control means and a second hydraulic circuit providing angular rotational capability to a secondary accessory control means;    using a control handle having manual actuatable inputs for regulating the hydraulic pump actuation of the first hydraulic circuit and the second hydraulic circuit and control over the steerable wheel and the powered drive wheel; and    regulating a vertical lifting and lowering capability of a pair of loader arms pivotably attached to the frame by said first hydraulic circuit and angularly regulating an accessory attachment mechanism supported by the loader arms by said second hydraulic circuit.