Systems and methods for steering vehicles
View Patent ↗In one embodiment, a vehicle comprises a body, a steerable drive wheel attached to the body, and a load platform connected to the body that is movable between a lowered position and a lifted position. A load wheel is connected to the load platform and an intermediate load wheel is connected to the vehicle and positioned between the drive wheel and the load wheel. The load wheel is configured to facilitate moving the load platform between the lowered position and the lifted position and the intermediate load wheel is configured to cooperate with the load wheel to facilitate moving the load platform between the lowered position and the lifted position. The intermediate load wheel is also configured to form a pivot about which the vehicle turns throughout a range of motion of the load platform between and including the lowered position and the lifted position.
1. A vehicle comprising:
a body;
a drive wheel attached to the body, wherein the drive wheel is configured to steer the vehicle;
a load platform connected to the body, wherein the load platform is configured to move between a fully lowered position and a fully lifted position;
a load wheel connected to the load platform, wherein the load wheel is configured to facilitate moving the load platform between the fully lowered position and the fully lifted position; and
an intermediate load wheel connected to the vehicle, wherein the intermediate load wheel is positioned between the drive wheel and the load wheel, the intermediate load wheel is configured to cooperate with the load wheel to facilitate moving the load platform between the fully lowered position and the fully lifted position, and the intermediate load wheel is configured to form a pivot about which the vehicle turns throughout a range of motion of the load platform between and including the fully lowered position and the fully lifted position.
2. A vehicle according to claim 1 , wherein the load wheel is further configured to swivel throughout a range of motion of the load platform between and including the fully lowered position and the fully lifted position.
3. A vehicle according to claim 1 , further comprising:
a swivel wheel located proximate to the load wheel, wherein the swivel wheel is configured to contact the ground when the load platform is at the fully lowered position; and
wherein the load wheel is further configured to disengage the ground when the load platform is at the fully lowered position.
4. A vehicle comprising:
a body;
a drive wheel attached to the body, wherein the drive wheel is configured to steer the vehicle;
a load platform connected to the body, wherein the load platform is configured to move between a lowered position and a lifted position;
a load wheel connected to the load platform, wherein the load wheel is configured to facilitate moving the load platform between the lowered position and the lifted position;
an intermediate load wheel connected to the vehicle, wherein the intermediate load wheel is positioned between the drive wheel and the load wheel, the intermediate load wheel is configured to cooperate with the load wheel to facilitate moving the load platform between the lowered position and the lifted position, and the intermediate load wheel is configured to form a pivot about which the vehicle turns throughout a range of motion of the load platform between and including the lowered position and the lifted position; and
a mechanical linkage connected to the load wheel and the intermediate load wheel, wherein the mechanical linkage is configured to cause the load wheel and the intermediate load wheel to simultaneously move towards and away from the load platform when the load platform is moved between the lowered position and the lifted position, respectively.
5. A vehicle according to claim 1 , further comprising a motor operatively connected to the drive wheel and configured to apply motive power to the drive wheel to move the vehicle.
6. A vehicle according to claim 1 , further comprising:
a pivot joint, wherein the pivot joint is configured to permit an end of the load platform that is distal from the body to move above and below the pivot joint; and
a mechanical stop associated with the pivot joint, wherein the mechanical stop is configured to limit a range of pivoting motion of the load platform.
7. A vehicle according to claim 6 , wherein the pivot joint is interposed between portions of the load platform.
8. A vehicle comprising:
a body;
a drive wheel attached to the body, wherein the drive wheel is configured to steer the vehicle;
a load platform connected to the body, wherein the load platform is configured to move between a lowered position and a lifted position;
a load wheel connected to the load platform, wherein the load wheel is configured to facilitate moving the load platform between the lowered position and the lifted position;
an intermediate load wheel connected to the vehicle, wherein the intermediate load wheel is positioned between the drive wheel and the load wheel, the intermediate load wheel is configured to cooperate with the load wheel to facilitate moving the load platform between the lowered position and the lifted position, and the intermediate load wheel is configured to form a pivot about which the vehicle turns throughout a range of motion of the load platform between and including the lowered position and the lifted position; and
a first portion of a vehicle weight and a load weight is carried by the load wheel and the intermediate load wheel, a second portion of the vehicle weight and the load weight is carried by the drive wheel, and a majority of the first portion of the vehicle weight and the load weight is borne by the intermediate load wheel for an entire range of motion of the load platform.
9. A method of vehicle operation comprising:
in response to receiving a command to lower a load platform of a vehicle, lowering the load platform to a fully lowered position at least partially via a load wheel and an intermediate load wheel positioned between the load wheel and a drive wheel;
in response to receiving a steering command, turning the drive wheel and pivoting the vehicle about a pivot defined by the intermediate load wheel with the load platform at the fully lowered position;
in response to receiving a command to lift a load platform of the vehicle, lifting the load platform at least partially via the load wheel and the intermediate load wheel positioned between the load wheel and the drive wheel; and
in response to receiving a steering command, turning the drive wheel and pivoting the vehicle about the pivot with the load platform at a lifted position.
10. A vehicle comprising:
a body;
a drive means for steering the vehicle connected to the body;
a load platform connected to the body, wherein the load platform is configured to move between a fully lowered position and a lifted position; and
a load lifting means for moving the load platform between a lowered position and a lifted position, wherein the load lifting means includes turning means for providing a pivot about which the vehicle turns throughout a range of motion of the load platform between and including the fully lowered position and the lifted position.
11. A vehicle according to claim 1 , wherein the intermediate load wheel is connected to the load platform.
12. A vehicle according to claim 3 , further comprising an alignment feature connected to the load platform, wherein the alignment feature is configured to engage the load wheel as the load platform is lowered.
13. A vehicle according to claim 11 , wherein the load platform comprises a pair of forks.
14. A vehicle comprising:
a body;
a drive wheel attached to the body, wherein the drive wheel is configured to steer the vehicle;
a load platform connected to the body, wherein the load platform is configured to move between a lowered position and a lifted position;
a load wheel connected to the load platform, wherein the load wheel is configured to facilitate moving the load platform between the lowered position and the lifted position; and
an intermediate load wheel connected to the vehicle, wherein the intermediate load wheel is positioned between the drive wheel and the load wheel, the intermediate load wheel is configured to continuously contact the ground throughout a full range of motion of the load platform, and the intermediate load wheel is configured to form a pivot about which the vehicle turns throughout the full range of motion of the load platform.