Hydrostatic Axial Piston Machine Utilizing A Bent-Axis Construction

Abstract

A hydrostatic axial piston machine ( 1 ) with a bent-axis construction has a drive shaft ( 4 ) with a drive flange ( 3 ) rotatable around an axis of rotation (R t ). A cylinder drum ( 7 ) has an axis of rotation (R z ). The cylinder drum ( 7 ) has a plurality of piston bores ( 8 ) located concentric to the axis of rotation (R z ) of the cylinder drum ( 7 ) and a longitudinally displaceable piston ( 10 ) is located in each bore ( 8 ). A driving device drives the cylinder drum ( 7 ). The drive shaft ( 4 ) is a hollow shaft. A torque bar ( 31 ) runs through the hollow shaft from a drive flange side end of the axial piston machine ( 1 ) to a cylinder drum side end of the axial piston machine ( 1 ) to transmit torque from the drive flange side end of the axial piston machine ( 1 ) to a cylinder drum side end of the axial piston machine ( 1 ).

The invention claimed is: 
     
         1 . A hydrostatic axial piston machine with a bent-axis construction, comprising:
 a drive shaft having an axis of rotation and provided with a drive flange;   a cylinder drum having an axis of rotation;   a plurality of piston bores located in the cylinder drum and concentric to the axis of rotation of the cylinder drum;   a longitudinally displaceable piston located in each piston bore;   a driving device to drive the cylinder drum and   wherein the drive shaft comprises a hollow shaft, and wherein a torque bar extends through the hollow shaft for the transfer of a torque from a drive flange side end of the axial piston machine to a cylinder drum side end of the axial piston machine.   
     
     
         2 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the torque bar has no mechanical operative connection to the drive shaft. 
     
     
         3 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the drive shaft includes torque transmission means on the drive flange side end for transmission of torque. 
     
     
         4 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the cylinder drum includes a longitudinal recess located concentric to the axis of rotation of the cylinder drum, by means of which at least one of the torque bar and the drive shaft with the drive flange extend through the cylinder drum. 
     
     
         5 . The hydrostatic axial piston machine as recited in  claim 4 , wherein the drive shaft includes additional torque transmission means for transfer of torque on the cylinder drum side end. 
     
     
         6 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the drive shaft is cantilever-mounted in a housing of the axial piston machine. 
     
     
         7 . The hydrostatic axial piston machine as recited in  claim 4 , wherein the drive shaft is mounted in a housing of the axial piston machine on both sides of the cylinder drum. 
     
     
         8 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the driving device for the drive of the cylinder drum includes connecting rods, each of which is located at least partly in the piston, and each of which is connected in an articulated manner with the piston and with the drive flange by a ball-and-socket joint. 
     
     
         9 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the driving device for the drive of the cylinder drum includes the pistons, which are displaceable longitudinally in the piston bores of the cylinder drum, and wherein the pistons are tapered or spherical and are provided with a tapered or spherical generated surface. 
     
     
         10 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the driving device for the cylinder drum includes a driving joint located between the cylinder drum and the drive shaft or the drive flange. 
     
     
         11 . The hydrostatic axial piston machine as recited in  claim 10 , wherein the driving joint is a constant velocity joint. 
     
     
         12 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the drive flange is one piece with the drive shaft. 
     
     
         13 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the drive flange and the drive shaft are separate parts, with the drive flange connected torque-tight with the drive shaft. 
     
     
         14 . The hydrostatic axial piston machine as recited in  claim 1 , wherein a spherical guide for mounting the cylinder drum is formed by a sphere and a spherical cap and is located between the drive shaft and the cylinder drum. 
     
     
         15 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the axial piston machine is a constant displacement machine with a constant displacement volume. 
     
     
         16 . The hydrostatic axial piston machine as recited in  claim 1 , wherein the axial piston machine is a variable displacement machine with a variable displacement volume, wherein the inclination of the axis of rotation of the cylinder drum is variable with respect to the axis of rotation of the drive shaft. 
     
     
         17 . A power split transmission, comprising:
 A hydrostatic axial piston machine, wherein the axial piston machine comprises:   a drive shaft having an axis of rotation and provided with   a drive flange;   a cylinder drum having an axis of rotation;   a plurality of piston bores located in the cylinder drum and concentric to the axis of rotation of the cylinder drum;   a longitudinally displaceable piston located in each piston bore;   a driving device to drive the cylinder drum and   wherein the drive shaft comprises a hollow shaft, and wherein a torque bar extends through the hollow shaft to transmit a torque from a drive flange side end of the axial piston machine to a cylinder drum side end of the axial piston machine.