US 5,701,738 A · Mechanical disconnect for variable speed hydrostatic transmission

Abstract

A mechanical disconnection mechanism for a hydrostatic transmission. The output shaft of the hydrostatic transmission is divided into a drive portion and a driven portion, with both the drive portion and the driven portion being provided with external splines or gears. To connect the drive portion to the driven portion, a splined sleeve is positioned to engage the splines of both the driven portion and the drive portion such that rotation of the drive portion rotates the driven portion. To disconnect the drive portion from the driven portion, the splined sleeve is positioned to engage only one of the drive portion and the driven portion. In the disconnected position, the implement may be manually pushed without reverse driving the hydraulic unit of the transmission to thereby allow for relatively easy movement. A brake is mounted about the driven portion of the output shaft to enable the vehicle to be stopped regardless of the position of the splined sleeve.

Claims18

Dependent claims

A hydrostatic transmission for use in lawn and garden implements, comprising:

a hydraulic unit including a pump, a motor, and a hydraulic passage communicating hydraulic fluid between said pump and said motor;
an output shaft coupled to said hydraulic unit, said output shaft having a drive portion and a driven portion, said driven portion being independent of said drive portion;
a shaft brake operably connected to said driven portion, which when engaged stops rotation of said driven portion;
and
a selectively engageable disconnection mechanism adjacent said output shaft, said disconnection mechanism connecting said drive portion to said driven portion when engaged, and disconnecting said drive portion from said driven portion when disengaged, said driven portion being rotatable without resistance from said hydraulic unit when said disconnection mechanism is disengaged.

2 more elements

A hydrostatic transaxle for use in lawn and garden implements, comprising:

a hydraulic unit including a pump, a motor, and a hydraulic passage communicating hydraulic fluid between said pump and said motor;
an output shaft coupled to said hydraulic unit, said output shaft having a drive portion and a driven portion, said driven portion being independent of said drive portion;
a pair of axles for propelling a vehicle, said driven portion being coupled to said axles through a differential mechanism and a gear train including a succession of gears such that rotation of said driven portion causes rotation of said axles;
a shaft brake operably connected to said driven portion and disposed ahead of said differential, which when engaged stops rotation of said driven portion and said gear train;
and
a selectively engageable disconnection mechanism ahead of said brake and adjacent said output shaft, said disconnection mechanism connecting said drive portion to said driven portion when engaged, and disconnecting said drive portion from said driven portion when disengaged, said axles, gear train and said driven portion rotating independently of said drive portion and said hydraulic unit when said disconnection mechanism is disengaged.

3 more elements

A hydrostatic transaxle for use in lawn and garden implements, comprising:

a hydraulic unit including a pump, a motor, and a hydraulic passage communicating hydraulic fluid between said pump and said motor;
an output shaft coupled to said hydraulic unit,
a transfer shaft operably coupled between said output shaft and a differential, said transfer shaft having a drive portion and a driven portion, said driven portion being independent of said drive portion;
and
a shaft brake operably connected to said driven portion, which when engaged stops rotation of said driven portion;
and
a selectively engageable disconnection mechanism adjacent said transfer shaft, said disconnection mechanism connecting said drive portion to said driven portion when engaged, and disconnecting said drive portion from said driven portion when disengaged, said driven portion being rotatable without resistance from said hydraulic unit when said disconnection mechanism is disengaged.

4 more elements

Dependencies are inferred from the claim text.

Mechanical disconnect for variable speed hydrostatic transmission

Life of this patent

Mechanical disconnect for variable speed hydrostatic transmission

Life of this patent

Abstract

Claims18