Three wheel drive vehicle

A vehicle comprising:

• a frame having a first portion and a second portion, first wheels operatively connected to the first portion of the frame, fluid operated first motors, one of said first motors being drivably connected to one first wheel, the other of said first motors being drivably connected to the other first wheel, second wheel means operatively connected to the second portion of the frame, a fluid operated second motor drivably connected to the second wheel means, a pump assembly having a first pump for supplying fluid under pressure to the first motors, and a second pump for supplying fluid under pressure to the second motors, whereby said first motors and second motors concurrently operate to drive the first wheel means and the second wheel means, means for operating said pump assembly, said frame includes first and second beams longitudinally located generally along opposite sides of the vehicle, said pump assembly having a driven shaft, said means for operating said pump assembly being an internal combustion engine having a drive shaft, power transmitting means operably connecting said drive shaft with said driven shaft whereby said engine powers said pump assembly, sub-frame means mounted on the first and second beams, means connecting the pump assembly and engine to said sub-frame means locating said pump assembly and engine transversely of said first and second beams, and means releasably mounting the sub-frame means on the first and second beams whereby the pump assembly, engine, and sub-frame means can be removed as a unit from the frame.

A land vehicle comprising:

• a frame, a first wheel means and second wheel means connected to the frame to support the frame on the ground, first drive means operably connected to the first wheel means to rotate said first wheel means, said first drive means having fluid operated first motor means, second drive means operably connected to the second wheel means, said second drive means having fluid operated second motor means, first pump means for supplying fluid under pressure to a first fluid circuit connected to the first motor means, second pump means for supplying fluid under pressure to a second fluid circuit connected to the second motor means, means for concurrently operating the first and second pump means whereby said first and second pump means supplies fluid under pressure to the first and second fluid circuits thereby operating said first and second motors to drive the first and second wheel means, said first and second pump means each having control means operable to vary the rate of flow of fluid discharged by the first and second pump means, means connected to the control means of one of the pump means operable to actuate the control means of said one of the pump means, means operable in response to a difference in the pressure of the fluid in the first and second fluid circuits to actuate the control means of other pump means to alter the rate of flow of fluid discharged bythe other pump means to substantially balance the pressure of the fluid in the first and second fluid circuits thereby maintaining the torque and speed input to the first and second drive wheel means substantially constant, and means having fluid flow restricting means interconnecting the first fluid circuit with the second fluid circuit whereby fluid under high pressure in one fluid circuit flows to the other fluid circuit increasing the pressure of the fluid therein, said means operable in response to a difference in the pressure of the fluid in the first and second fluid circuits to actuate the control means of the other pump means to alter the rate of flow of fluid discharged by the other pump means includes a piston and cylinder assembly connected to the control means of both pump means, and shuttle valve means connected to said first and second fluid circuits in parallel with said means having fluid flow restricting means to receive fluid under pressure therefrom and direct fluid to the piston and cylinder assembly, said shuttle valve means operable in response to a difference in fluid pressure in the first and second fluid circuits to selectively expand and contract the piston and cylinder assembly thereby operating the control means of the other pump means to alter the fluid flow rate of the other pump means in a manner to balance the pressure of the fluid in the first and second fluid circuits thereby maintaining the torque and speed input to the front and rear drive wheel means substantially constant.

A land vehicle comprising:

• a frame, first wheel mans and second wheel means connected to the frame to support the frame on the ground, first drive means operably connected to the first wheel means to rotate said first wheel means, said first drive means having fluid operated first motor means, second drive means operably connected to the second wheel means, said second drive means having fluid operated second motor means, first pump means for supplying fluid under pressure to a first fluid circuit connected to the first motor means, second pump means for supplying a fluid under pressure to a second fluid circuit connected to the second motor means, means for concurrently operating the first and second pump means whereby said first and second pump means supplies fluid under pressure to the first and second fluid circuits thereby operating said first and second motors to drive the first and second wheel means, said first and second pump means each having control means operable to vary the rate of flow of fluid discharged by the first and second pump means, means connected to the control means of one of the pump means operable to actuate the control means of said one of the pump means, means operable in response to a difference in the pressure of the fluid in the first and second fluid circuits to actuate the control means of other pump means to alter the rate of flow of fluid discharged by the other pump means to substantially balance the pressure of the fluid in the first and second fluid circuits thereby maintaining the torque and speed input to the first and second drive wheel means substantially constant, and means having fluid flow restricting means interconnecting the first fluid circuit with the second fluid circuit whereby fluid under high pressure in one fluid circuit flows to the other fluid circuit increasing the pressure of the fluid therein, said means operable to actuate the control means of the other pump means includes a piston and cylinder unit operably connected to the control means of both of said pump means, and shuttle vavle means connecting the unit with said first and second fluid circuits in parallel with said means having fluid flow restricting means, said shuttle valve means being operable in response to a difference in fluid pressure of the first and second fluid circuits to supply fluid to said unit to control the fluid output of the other pump means in a manner to substantially balance the fluid pressure in the first and second fluid circuits.