Variable wheel base vehicle

Abstract

A variable wheel base vehicle includes a vehicle body having front end rear ends supporting body members one of which is capable of displacement relative to the other. Drive motors mounted to the vehicle body are linked to the body members. A carriage assembly including drive wheels provide support for the vehicle body. An extension assembly responsive to the drive motor is connected to at least one of the body members. Upon actuation of the drive motor, the extension assembly enables one body member to displace relative to the other body member to enable extension and retraction of the vehicle wheel base. Each body member includes at least one wheel of the carriage assembly and, as a result of displacement of one body member relative to the other body member, the displaced body member provides increased counterbalance in the vehicle.

1. A mobile vehicle for lifting a load, comprising:
 a vehicle body including front and rear wheel assemblies each including at least a pair of wheels supporting respective front and rear vehicle body parts; 
 an implement attached to the vehicle body for lifting said load; 
 a drive motor and controlling hydraulic pump mounted on the vehicle to said rear vehicle body part such that a substantial portion of the vehicle weight is carried by the rear vehicle body part of the vehicle; 
 an independent extension and retraction assembly responsive to actuation of the drive motor and mounted within said vehicle body; 
 a controller for actuating the extension and retraction assembly responsive to an input from an operator of the vehicle; 
 wherein the extension and retraction assembly allows the vehicle to move between a retracted state in which the extension and retraction assembly is fully retracted and the body parts are in opposition and where a wheel base distance is at a minimum for the vehicle and an extended state in which the extension and retraction assembly is fully extended so that the body parts are at least partially separated and the wheel base is set at a maximum for the vehicle; wherein, when the vehicle is extended, one wheel assembly supporting one of said body parts is displaced relative to the other wheel assembly supporting the other body part, the drive motor providing counterbalance for said load and resistance against overturning under said load,;  
 wherein at least one wheel of one or both said front wheel assemblies assembly includes at least one an independent hydraulic wheel motor and 
 wherein a hydraulic network is provided comprising a plurality of hydraulic hoses and one or more associated hose guides in which said hoses travel to accommodate displacement of the body parts between a said controlling pump mounted on one of the front and rear body parts part and said at least one wheel motor displace to accommodate displacement of the body parts of said front wheel assembly. 
 
     
     
       2. A vehicle according to  claim 1  wherein the front and rear body parts each receive a member of said extension assembly such that actuation of the extension assembly causes displacement of the rear body part of the vehicle relative to the front body part. 
     
     
       3. A vehicle according to  claim 2  wherein the front and rear wheel assemblies support the respective front and rear body parts and wherein the drive motor is mounted on the rear body part and moves with said rear body part. 
     
     
       4. A vehicle according to  claim 3  wherein the extension assembly comprises a hydraulically operated telescopic member having a fixed member fixed to the front body part and a movable member fixed to the rear body part. 
     
     
       5. A vehicle according to  claim 1  further comprising said controlling pump being a hydraulic pump driven by the drive motor and being linked to the extension assembly via hydraulic hoses in communication with at least one control valve. 
     
     
       6. A vehicle according to  claim 5  wherein the hydraulic hoses between said hydraulic pump and control valve move to accommodate displacement of said rear body part. 
     
     
       7. A vehicle according to  claim 6  wherein two fixed hydraulic hoses link the control valve to the telescopic member forming the extension and retraction assembly. 
     
     
       8. A vehicle according to  claim 7  wherein the telescopic member includes therein a hydraulic cylinder which extends and retracts to facilitate extension and retraction of said extension assembly. 
     
     
       9. A vehicle according to  claim 8  wherein each body part includes two independently driven wheels. 
     
     
       10. The vehicle of  claim 1 , wherein said extension and retraction assembly is mounted entirely within, without protruding upwardly from, the vehicle body. 
     
     
       11. A vehicle for lifting loads, comprising:
 a vehicle body comprising front and rear body parts; carriage means for said vehicle body comprising front and rear wheel assemblies, each including at least a pair of wheels; 
 a drive motor mounted on the vehicle to said rear body part such that a substantial portion of the weight of said drive motor is carried by said rear body part of said vehicle; 
 a load lifting implement attached to said body for lifting said loads; 
 an extension and retraction assembly responsive to the drive motor and fitted within the body of the vehicle thereby allowing the vehicle to move responsive to an input from an operator of the vehicle between a retracted state in which a wheel base of the vehicle is at a minimum and the extension and retraction assembly is fully retracted, and an extended state where the wheel base distance is at a maximum and the extension and retraction assembly is fully extended; 
 wherein said extension and retraction assembly further comprises a pair of spaced generally parallel telescoping members mounted within the vehicle body connected to extend and retract said wheel base; 
 wherein in said extended state the rear wheel assembly is rearwardly displaced relative to the front wheel assembly, wherein the extension and retraction assembly causes the vehicle body to part into front and rear body parts each of which are connected to the extension and retraction assembly and which are supported by the front and rear wheel assemblies respectively; 
 wherein the drive motor moves with the rear body thereby providing counter balance against vehicle instability, wherein each wheel includes a wheel motor and hydraulic hoses between a controlling hydraulic pump located on one of said front and rear body parts and at least one pair of wheel motors moves to accommodate displacement of the moveable body parts. 
 
     
     
       12. A vehicle according to  claim 11  wherein the hydraulic pump is driven by the drive motor and is linked to the extension assembly via hydraulic hoses which join the pump to control a valve. 
     
     
       13. A vehicle according to  claim 12  where the hydraulic hoses between the pump and control valve move to accommodate displacement of said rear body relative to the front body part. 
     
     
       14. The vehicle of  claim 11 , wherein said extension and retraction assembly is mounted entirely within, without protruding upwardly from, the vehicle body. 
     
     
       15. A skid steer vehicle according to  claim 14  wherein the front and rear parts body together form the vehicle body each of which body parts are attached to a member of said extension assembly such that actuation of the extension assembly causes longitudinal displacement of the rear part relative to the front body part. 
     
     
       16. A skid steer vehicle according to  claim 15  wherein the extension assembly includes at least one telescopic member having one member fixed to the front body part and a moveable member fixed to the rear body part,
 wherein the telescopic member is hydraulically operated. 
 
     
     
       17. The vehicle of  claim 11 , wherein said vehicle is a skid steer vehicle. 
     
     
       18. A mobile vehicle for lifting a load, comprising:
 a vehicle body including front and rear vehicle body parts each including and supported by a separate wheel assembly, each wheel assembly including at least a pair of wheels, each of said wheels being coupled to a wheel motor;   an implement attached to the vehicle body for lifting said load;   an extension and retraction assembly coupled to said front and rear vehicle body parts and mounted within said vehicle body;   wherein, when the vehicle is extended, one wheel assembly supporting one of said body parts is displaced relative to the other body part;   a controller in communication with at least one control valve for actuating the extension and retraction assembly in response to an input from an operator of the vehicle;   a drive motor mounted on the rear vehicle body part of the vehicle body and coupled to a plurality of hydraulic pumps, the drive motor and pumps being positioned such that a substantial portion of their combined weight is carried by the rear vehicle body part, the weight of said drive motor and said plurality of pumps providing counterbalance for said load and resistance against overturning of the vehicle under said load;   a network of hoses linked to said at least one control valve for carrying hydraulic fluid between at least one of said pumps and said extension and retraction assembly such that said extension and retraction assembly is responsive to actuation of said controller thereby causing the drive motor and said at least one of said pumps to displace the wheel assemblies supporting said front and rear vehicle body parts with respect to each other and move said front and rear vehicle body parts between a retracted state in which the extension and retraction assembly is fully retracted and the body parts are in opposition and where a wheel base distance is at a minimum for the vehicle and an extended state in which the extension and retraction assembly is fully extended so that the body parts are at least partially separated and the wheel base is set at a maximum for the vehicle;   a network comprising a plurality of hydraulic hoses for carrying hydraulic fluid between at least one of said pumps and each of said wheel motors to provide drive for the wheels, said network of hoses carrying hydraulic fluid between said pumps and each of said wheel motors of said front wheel assembly being long enough to undergo displacement upon actuation of the extension and retraction assembly to accommodate the maximum and minimum wheel base of the vehicle and associated hose guides in which said hoses travel are provided.   
     
     
       19. A mobile vehicle for lifting a load, comprising:
 a vehicle body including front and rear body parts respectively supported by front and rear wheel assemblies each assembly including at least a pair of wheels for support;   an implement attached to the front body part of the vehicle body for lifting said load;   a drive motor and controlling hydraulic pump mounted on said rear vehicle body part of the vehicle such that a substantial portion of the combined weight of said drive motor and controlling pump is carried by the rear vehicle body part of the vehicle;   wherein at least one wheel of one or both said wheel assemblies includes at least one wheel motor and wherein hydraulic hoses between said controlling pump mounted on said rear body part and said at least one wheel motor displace to accommodate displacement of the body parts;   an extension and retraction assembly, including at least one telescopically deployed member mounted within the vehicle body, responsive to actuation of the drive motor and mounted within said vehicle body;   a controller for actuating the extension and retraction assembly responsive to an input from an operator of the vehicle;   wherein the extension and retraction assembly allows the vehicle to move between a retracted state in which the extension and retraction assembly is fully retracted and the body parts are in opposition and where a wheel base distance is at a minimum for the vehicle and an extended state in which the extension and retraction assembly is fully extended so that the body parts are at least partially separated and the wheel base is set at a maximum for the vehicle;   wherein, when the vehicle is extended, one wheel assembly supporting one of said body parts is displaced relative to the other wheel assembly supporting the other body part, the drive motor providing counterbalance for said load and resistance against overturning under said load;   wherein a hydraulic network is provided comprising a plurality of hydraulic hoses and one or more associated hose guides in which said hoses travel to accommodate displacement of the body parts between said controlling pump mounted on the rear body part and said at least one wheel motor of said front wheel assembly.   
     
     
       20. A mobile vehicle for lifting a load, comprising:
 a vehicle body including a front wheel assembly each including at least a pair of wheels supporting respective front and rear vehicle body parts and a rear assembly including at least a pair of wheels supporting the rear vehicle body parts;   an implement comprising a fork lift arm or other mountable device attached to the vehicle body for lifting said load;   a drive motor and controlling pump mounted on said rear vehicle body part of the vehicle such that a substantial portion of the combined weight of said drive motor and controlling pump is carried by said rear vehicle body part and wherein the motor and controlling pump act as a counter balance weight to said load when said load is lifted by the implement;   wherein at least one wheel of one or both said wheel assemblies includes at least one wheel motor and wherein hydraulic hoses between said controlling pump mounted on said rear body part and said at least one wheel motor displace to accommodate displacement of the body parts;   an extension and retraction assembly responsive to actuation of the drive motor and mounted within said vehicle body;   a controller for actuating the extension and retraction assembly responsive to an input from an operator of the vehicle;   wherein the extension and retraction assembly allows the vehicle to move between a retracted state in which the extension and retraction assembly is fully retracted and the body parts are in opposition and where a wheel base distance is at a minimum for the vehicle and an extended state in which the extension and retraction assembly is fully extended so that the body parts are at least partially separated and the wheel base is set at a maximum for the vehicle;   wherein, when the vehicle is extended, one wheel assembly supporting one of said body parts is displaced relative to the other wheel assembly supporting the other body part, the drive motor providing counterbalance for said load and resistance against overturning under said load;   wherein a hydraulic network is provided comprising a plurality of hydraulic hoses and one or more associated hose guides in which said hoses travel to accommodate displacement of the body parts between said controlling pump mounted on the rear body part and said at least one wheel motor of said front wheel assembly.   
     
     
       21. A vehicle according to claim 1 wherein at least one of the hydraulic hoses of the extension and retract assembly travels in a fabricated channel. 
     
     
       22. A vehicle according to claim 21 wherein the fabricated channels guide the hoses during extension and retraction by facilitating easy unrolling and rolling of the hoses. 
     
     
       23. A vehicle according to claim 1 wherein the implement comprises a fork lift. 
     
     
       24. A vehicle according to claim 1 wherein the implement comprises a lift arm and bucket arrangement. 
     
     
       25. A vehicle according to claim 1 wherein the extension and retraction assembly further comprises a telescoping member mounted within the vehicle body and further comprising symmetrically located assemblies generally parallel to said extension and retraction assembly to overcome rotational instability. 
     
     
       26. A vehicle according to claim 1 wherein an amount of extension is variable based on loading.