Vehicle steering and speed control
View Patent ↗A control system for a lawnmower includes a handlebar connected to the lawmnower for controlling direction and speed of travel of the lawmower based on a position of the handlebar relative to the lawnmower. The control system is connected to a drive system of the lawnmower such that changing the elevation of the handlebar adjusts operation of a number of wheel drive units and turning of the handlebar relative to the lawnmower adjusts operation of one wheel drive unit relative to another wheel drive unit.
1. A steering assembly for a utility vehicle having a first drive configured to move a first drive wheel and a second drive configured to move a second drive wheel located opposite the first drive wheel, comprising:
(A) a steering handle which is movable laterally relative to a frame of the vehicle to steer the vehicle in a turn direction and which is movable in a vertical direction to vary the speed of the vehicle; and
(B) a speed limiter variably positioned relative to the steering handle and selectively engageable by the steering handle, wherein movement of the speed limiter varies a maximum vertical movement of the steering handle relating to the frame and limits a maximum speed of the vehicle.
2. The steering assembly of claim 1 , wherein lateral movement of the steering handle along the speed limiter automatically slows a speed of one of the first drive and the second drive when the vehicle is maneuvering a turn.
3. The steering assembly of claim 2 , wherein the distance between the speed limiter and the steering handle determines a destroke rate of one of the first drive and second drive during a turning operation.
4. The steering assembly of claim 1 , further comprising a speed control lever assembly for adjusting a distance between the speed limiter and the steering handle.
5. The steering assembly of claim 1 , further comprising a calibration body constructed to tune operation of the first drive and a second drive with respect to a position of the steering handle relative to the speed limiter.
6. The steering assembly of claim 1 , wherein the speed limiter comprises a generally curvilinear body having a first end and a second end that are pivotally connected to generally opposite lateral sides of the vehicle.
7. The steering assembly of claim 1 , wherein the utility vehicle is a lawnmower.
8. A vehicle, comprising:
(A) a frame;
(B) a first drive configured to operate a first drive wheel;
(C) a second drive configured to operate a second drive wheel and located opposite the first drive wheel; and
(D) a steering control assembly having a steering handle operatively connected to the first and second drives by a steering rod and a plurality of drive rods that extend at least a majority of distance between the steering handle and the first and second drives, wherein lateral movement of the steering handle relative to the frame rotates the drive rods about the steering rod and steers the vehicle in a turn direction, and wherein movement in the steering handle in a vertical direction translates the steering rod and each of the drive rods in a fore or aft direction relative to the frame and controls forward and rearward movement of the vehicle.
9. The vehicle of claim 8 , further comprising a speed limiter control connected to the frame and constructed to define a range of vertical motion of the steering handle.
10. The vehicle of claim 9 , wherein the speed limiter control comprises a reference bar configured to limit movement of the steering handle based on a position of the speed limiter control.
11. The vehicle of claim 10 , wherein the reference bar moves away from the steering handle as the speed limiter control position is altered to increase operational speed of the mower.
12. The vehicle of claim 10 , wherein a maximum distance between a side of the reference bar and a corresponding side of the steering handle reduces a destroke of one of the first and second drives and a resultant deceleration during a turn.
13. The vehicle of claim 12 , wherein the destroke is proportional to the movement of the steering handle from a neutral position and the position of the speed limiter control.
14. The vehicle of claim 8 , wherein the vehicle is a lawnmower.
15. A method of controlling movement of a utility vehicle, comprising the steps of:
(A) moving a steering handle in a vertical direction to drive a vehicle in one of a forward and rearward direction of travel;
(B) moving the steering handle in a lateral direction from a central position relative to a frame of the vehicle to cause the vehicle to turn; and
(C) moving a reference bar to adjust a maximum range of motion of the steering handle and limit a maximum speed of travel of the vehicle.
16. The method of claim 15 , wherein the vehicle moves in a direction generally opposite the lateral direction of the steering handle.
17. The method of claim 15 , further comprising adjusting the position of a speed limiter to provide another maximum range of steering handle motion that is different than the first maximum range of motion.
18. The method of claim 15 , wherein the maximum range of motion of the steering handle is adjusted by adjusting a position of the reference bar relative to an at-rest position of the steering handle.
19. The method of claim 15 , wherein moving the steering handle in a lateral direction slows operation of a drive unit positioned on a side of the vehicle opposite the lateral direction.
20. The method of claim 19 , wherein the drive unit is hydraulic based and is slowed by destroking the drive unit relative to the operation of a drive unit attached to an opposite side of the vehicle.
21. The method of claim 15 , wherein the vehicle is at least one of a lawnmower, a utility cart, and a power buggy.
22. A lawnmower, comprising:
(A) a frame having a cutter deck mounted thereon;
(B) a first drive configured to operate a first drive wheel;
(C) a second drive configured to operate a second drive wheel located opposite the first drive wheel;
(D) a steering control assembly having a steering handle operatively connected to the first and second drives, wherein rotation of the steering handle about a generally vertical axis steers the vehicle in a turn direction, and wherein pivotal movement of the steering handle about a generally horizontal axis from a neutral position thereof increases forward movement of the vehicle; and
(E) a speed limiter control including a reference bar that is connected to the frame and that interacts with the steering handle upon pivotal motion of the steering handle into the reference bar to define a maximum range of pivotal motion of the steering handle, the reference bar being movable relative to the frame and to the steering handle to increase or decrease the maximum range of pivotal motion of the steering handle and, thereby, increase or decrease a maximum operational speed of the mower.
23. The vehicle of claim 22 , wherein the reference bar and steering handle are shaped such that, at any given position of the reference bar, when the steering handle is pivoted into contact with the reference bar and is rotated to increase a turning angle of the lawnmower, the handle pivots toward its neutral position to increase a destroke of one of the first and second drives and decelerate the lawnmower.
24. The vehicle of claim 23 , wherein the destroke and resultant lawnmower deceleration are proportional to the rotational movement of the steering handle from a neutral position.
25. The vehicle of claim 24 , wherein the destroke and resultant lawnmower deceleration increases with an increase in an at-rest spacing between the handle and the reference bar and a resultant increase in range of maximum pivotal motion of the steering handle.