Hydrostatic transmission with internal fluid expansion chamber

A hydrostatic and gear transmission comprising a housing structure defining a hydrostatic chamber and a gear chamber, an interior bulkhead wall formed in said housing structure between respective hydrostatic and gear chambers and where said bulkhead wall is provided with a corridor;

• a hydrostatic transmission disposed in said hydrostatic chamber and said hydrostatic chamber substantially full to capacity with hydrostatic fluid;
• a gear train disposed in said gear chamber and said gear chamber holding lubricating fluid for said gear train;
• a mechanical differential disposed in said gear chamber;
• a pair of axle shafts rotatably supported in said housing structure and extending outwardly from said housing structure, said axle shafts drivingly connected to said mechanical differential and said mechanical differential drivingly connected to said gear train;
• a duct disposed in said housing structure and said duct fluidly interconnecting said hydrostatic chamber and said gear chamber wherein said gear chamber acts as an overflow receiver for volume changes of said hydrostatic fluid in said hydrostatic chamber, said duct comprising:
• first and second openings at respective ends of said duct and where said first opening is in said hydrostatic chamber and where said second opening is in said gear chamber;
• said duct further comprising at least three distinctly shaped portions,
• a first portion disposed exclusively in said hydrostatic chamber and decending downwardly from the first opening,
• a second portion disposed in said gear chamber and accending upwardly,
• a third portion disposed in said gear chamber and decending downwardly towards the second opening,
• and wherein the first and second portions meet at a first joint and where said first joint extends through said corridor, second and third portions meeting at a second joint and where said second joint resides above said first joint.

A hydrostatic and gear transmission comprising a housing structure defining a hydrostatic chamber and a gear chamber;

• an interior bulkhead wall formed in said housing structure between respective hydrostatic and gear chambers and where said bulkhead wall is provided with a corridor;
• a hydrostatic transmission disposed in said hydrostatic chamber and said hydrostatic chamber substantially full to capacity with hydrostatic fluid;
• a gear train disposed in said gear chamber and said gear chamber holding lubricating fluid for said gear train;
• a duct disposed in said housing structure and said duct fluidly interconnecting said hydrostatic chamber and said gear chamber wherein said gear chamber acts as an overflow receiver for volume changes of said hydrostatic fluid in said hydrostatic chamber, said duct comprising:
• first and second openings at respective ends of said duct and where said first opening is in said hydrostatic chamber and where said second opening is in said gear chamber, said duct extending through said corridor;
• and further comprising means for the removal of metal particles of contamination in said gear chamber from entering said hydrostatic chamber, said means disposed near said second opening.

A hydrostatic transmission comprising a housing structure defining a hydrostatic chamber and a fluid overflow receiver chamber;

• an interior bulkhead wall formed in said housing structure between respective hydrostatic and fluid overflow receiver chambers and where said bulkhead wall is provided with a corridor;
• a hydrostatic transmission disposed in said hydrostatic chamber and said hydrostatic chamber substantially full to capacity with hydrostatic fluid;
• a duct disposed in said housing structure and said duct fluidly interconnecting said hydrostatic chamber and said fluid overflow receiver chamber wherein said fluid overflow receiver chamber acts as an overflow receiver for volume changes of said hydrostatic fluid in said hydrostatic chamber, said duct comprising:
• first and second openings at respective ends of said duct and where said first opening resides in said hydrostatic chamber and where said second opening resides in said fluid overflow receiver chamber;
• said duct further comprising at least three distinctly shaped portions,
• a first portion disposed exclusively in said hydrostatic chamber and decending downwardly from the first opening,
• a second portion disposed in said fluid overflow receiver chamber and accending upwardly,
• a third portion disposed in said fluid overflow receiver chamber and decending downwardly towards the second opening,
• and wherein the first and second portions meet at a first joint and where said first joint extends through said corridor, second and third portions meeting at a second joint and where said second joint resides above said first joint.