Patent ID: 6341479
Filing Date: 2002-01-29
Classification: A01D

Abstract:
A lawn mower comprising:a mower deck supporting an engine and having a pair of rear drive wheels mounted thereto; a handle bar assembly attached to and extending rearwardly and upwardly from the mower deck for controlling operation of the mower; an independent brake assembly mounted to each rear drive wheel for selectively braking the rear drive wheels, each brake assembly is coupled to a brake control lever attached to the handle bar assembly for individually actuating each brake assembly; a hydrostatic drive system coupled between the engine and the rear drive wheels for powering the rear drive wheels, wherein the hydrostatic drive system includes a variable hydraulic pump coupled to a fixed displacement hydraulic motor which is coupled to a differential transmission for driving the rear drive wheels; and a linkage mechanism coupled to the brake assemblies and the hydrostatic drive system for releasing hydraulic pressure from the hydrostatic drive system after actuation of at least one of the brake assemblies by the brake control levers to slow rotation of the drive wheels, wherein the linkage mechanism includes a dump valve actuating mechanism coupled to a hydraulic dump valve connected to the hydraulic pump which is actuated by the brake control levers to slow rotation of the rear drive wheels by releasing hydraulic pressure in the hydraulic pump coupled to the hydraulic motor and differential transmission for improved steering and control of the mower.