Hydromechanical transmission

Claim 2

A hydromechanical transmission, comprising: an input shaft; an axial piston hydraulic pump assembly associated with said shaft to be driven thereby; a movable swashplate operatively associated with said pump for selectively varying the displacement thereof; an axial piston hydraulic motor assembly coaxial with said pump; a floating valve plate disposed between and engaging said pump and said motor; a sun gear carried by one of said pump and said motor; a ring gear carried by the other of said pump and motor; a rotatable output carrier coaxial with said pump; and at least one planet gear carried by said carrier and meshed with both said sun and ring gears.

Claim 3

A hydromechanical transmission, comprising: an input shaft; an axial piston hydraulic pump assembly secured to said shaft for rotation therewith; a movable swashplate operatively associated with said pump for selectively varying the displacement thereof; an axial piston hydraulic motor assembly coaxial with said pump and remote from said swashplate; a valve plate disposed between and engaging said pump and said motor; a sun gear carried by said motor; a ring gear carried by said pump remote from said swashplate; a rotatable output carrier coaxial with said shaft and surrounding said motor; at least one planet gear carried by said carrier and meshed with both said sun and ring gears.

Claim 4

A hydromechanical transmission, comprising: an input shaft; an axial piston hydraulic pump assembly secured to said shaft for rotation therewith; a movable swashplate operatively associated with said pump for selectively varying the displacement thereof; an axial piston hydraulic motor assembly coaxial with said pump and remote from said swashplate; a valve plate disposed between and engaging said pump and said motor; a sun gear carried by said motor; a ring gear carried by said pump remote from said swashplate; a rotatable output carrier coaxial with said shaft and surrounding said motor; at least one planet gear carried by said carrier and meshed with both said sun and ring gears.

Claim 5

The hydromechanical transmission of claim 2 wherein said output carrier includes an interior bore receiving said motor, said motor being journalled for rotation within said bore.

Claim 6

A hydromechanical transmission, comprising: an axial piston hydraulic pump assembly; a pivotal swashplate operatively associated with said pump for selectively varying the displacement thereof; means for relatively rotating said pump and said swashplate about a predetermined axis; an axial piston hydraulic motor assembly coaxial with said pump axis and journalled for rotation relative to said pump about said axis; a floating valve plate disposed between said pump and said motor to establish a hydraulic fluid flow path therebetween, said valve plate including a stem extending through one of said pump and said motor; a conduit in said stem and adapted to be connected to a source of hydraulic fluid; a sun gear carried by one of said pump and said motor; a ring gear carried by the other of said pump and motor; a rotatable output carrier coaxial with said motor; and at least one planet gear carried by said carrier and meshed with both said sun and ring gears.

Claim 7

A hydromechanical transmission, comprising: an axial piston hydraulic pump assembly; a pivotal swashplate operatively associated with said pump for selectively varying the displacement thereof; means for relatively rotating said pump and said swashplate about a predetermined axis; an axial piston hydraulic motor assembly coaxial with said pump axis and journalled for rotation relative to said pump about said axis; a floating valve plate disposed between said pump and said motor to establish a hydraulic fluid flow path therebetween, said valve plate including a stem extending through one of said pump and said motor; a conduit in said stem and adapted to be connected to a source of hydraulic fluid; a sun gear carried by one of said pump and said motor; a ring gear carried by the other of said pump and motor; a rotatable output carrier coaxial with said motor; and at least one planet gear carried by said carrier and meshed with both said sun and ring gears.

Claim 8

The hydromechanical transmission of claim 4 wherein said ring gear is defined by a bell-shaped housing secured to said other of said pump and said motor and opening toward said one of said pump and said motor.

Claim 9

The hydromechanical transmission of claim 5 wherein said output carrier comprises a tubular structure internally journalling said one of said motor and said pump and including exterior, peripheral drive means adapted to be engaged with an element to be driven.

Claim 10

A hydromechanical transmission, comprising: an input shaft; an axial piston hydraulic pump assembly associated with said shaft to be driven thereby; a movable swashplate operatively associated with said pump for selectively varying the displacement thereof; an axial piston hydraulic motor assembly coaxial with said pump; interconnecting valve means disposed between said pump and said motor; a sun gear carried by one of said pump and said motor; a ring gear carried by the other of said pump and motor; a rotatable output carrier coaxial with said pump; at least one planet gear carried by said carrier and meshed with both said sun and ring gears; said gears being coplanar and lying in a plane located between said pump and motor assemblies.

Claim 11

A hydromechanical transmission, comprising: an input shaft; an axial piston hydraulic pump assembly associated with said shaft to be driven thereby; a movable swashplate operatively associated with said pump for selectively varying the displacement thereof; an axial piston hydraulic motor assembly coaxial with said pump; interconnecting valve means disposed between said pump and said motor; a sun gear carried by one of said pump and said motor; a ring gear carried by the other of said pump and motor; a rotatable output carrier coaxial with said pump; at least one planet gear carried by said carrier and meshed with both said sun and ring gears; said gears being coplanar and lying in a plane located between said pump and motor assemblies.

Claim 12

A hydromechanical transmission as defined in claim 7 wherein said valve means includes a floating valve plate, and each of said pump and motor assemblies includes a rotatable block with a series of chambers and a piston reciprocable in each chamber with said pistons being positioned within said chambers throughout the reciprocation thereof.