Patent ID: 8096374

Claim:
A vehicle, comprising: a chassis; a platform suspended from the chassis; a platform displacement mechanism configured to move the platform, relative to the chassis, between a first position and a second position; a variable drive unit mounted to the platform and comprising an input member movable, relative to a housing of the drive unit, between a first position and a second position; a control lever attached to the chassis and operatively connected to the drive unit, the control lever configured to vary a position of the input member relative to the housing, the control lever movable incrementally between a first position corresponding to the first position of the input member, and a second position corresponding to the second position of the input member; and a control linkage system comprising: a pivot link pivotally attached to the chassis at a chassis pivot; a control link comprising: a first end connected to the pivot link; and a second end connected to the control lever; and a drive link comprising: a first end pivotally connected to the pivot link at a first drive link pivot; and a second end pivotally connected to the input member at a second drive link pivot; wherein the linkage system is configured to maintain, as the platform is moved between the first and second positions, both the position of the input member relative to the drive unit, and a position of the control link relative to the chassis.