System for coupling a piston for a hydraulic pump motor

Abstract

A system ( 300 ) for coupling a piston for a hydraulic pump motor is provided for a hydraulic pump motor which includes a central rotor ( 3 ) of a pump motor which houses a hydraulic cylinder ( 14 ) inside of which a hydraulic piston ( 13 ) moves in translation and can push a tappet ( 18 ) guided by a hydraulic piston guided in translation by a tappet guide ( 19 ), the system ( 300 ) including a connection shaft ( 301 ) integral by a first end of the tappet ( 18 ) guided by a hydraulic piston and traversing the hydraulic piston ( 13 ) in the direction of its length via an orifice ( 307 ) of the connection shaft whereas a retention spring ( 304 ) is supported on the connection shaft ( 301 ) in the vicinity of a second end for maintaining this piston ( 13 ) in contact with the tappet ( 18 ) guided by the hydraulic piston.

1 . A system ( 300 ) for coupling a piston for a hydraulic pump motor provided for a hydraulic pump motor ( 1 ) which comprises a pump motor housing ( 2 ) in which a central rotor ( 3 ) of a pump motor is housed and which latter houses at least one hydraulic cylinder ( 14 ) inside of which a hydraulic piston ( 13 ) can move in translation and can push a tappet ( 18 ) guided by a hydraulic piston or can be pushed by the latter, which tappet ( 18 ) is guided in translation by a tappet guide ( 19 ) arranged in the central rotor ( 3 ) of the pump motor whereas a tangential arm ( 22 ) has a first end articulated in the central rotor ( 3 ) of the pump motor and has a second end which comprises a support face of the tangential arm ( 23 ) on the tappet which can exercise a force on a line of action of the tappet on the tangential arm ( 21 ) which comprises a crossbar of force ( 83 ) integral with the tappet ( 18 ) guided by the hydraulic piston, which tangential arm ( 22 ) furthermore comprises antifriction means ( 196 ) on its face located opposite the support face of the tangential arm ( 23 ) on the tappet, which means ( 196 ) is supported on the internal surface of a cylindrical casing of a peripheral rotor ( 32 ) which can rotate in a stator ( 65 ) of the peripheral rotor integral with the housing of the pump motor ( 2 ), which central rotor ( 3 ) of the pump motor is entirely or partially housed inside this peripheral rotor ( 29 ), wherein the system ( 300 ) comprises:
 At least one connection shaft ( 301 ) comprising a first end ( 302 ) integral with the tappet ( 18 ) guided by a hydraulic piston, which shaft ( 301 ) is positioned in the prolongation of this tappet ( 18 ) and traverses all or part of the hydraulic piston ( 13 ) in the direction of its length via an orifice ( 307 ) of the connection shaft;   At least one retention spring ( 304 ) which is directly or indirectly supported on the one hand on the connection shaft ( 301 ) in the vicinity of a second end ( 303 ) which comprises this shaft ( 301 ) and on the other hand on the hydraulic piston ( 13 ) in such a manner that this spring ( 304 ) tends to keep this piston ( 13 ) in contact with the tappet ( 18 ) guided by the hydraulic piston in the prolongation in which this piston ( 13 ) is positioned.   
     
     
         2 . The system for coupling a piston according to  claim 1 , wherein the support face of the arm tangential to the tappet ( 23 ) is kept in contact with the action line of the tappet on the tangential arm ( 21 ) by a tappet placement spring ( 305 ) which is directly or indirectly supported on the one hand on the tangential arm ( 22 ) and on the other hand on the tappet ( 18 ) guided by the hydraulic piston. 
     
     
         3 . The system for coupling a piston according to  claim 2 , wherein the tappet placing spring ( 305 ) is constituted by at least one steel blade ( 306 ) whose one end is integral with the tangential arm ( 22 ) and whose other end is supported on the force traverse ( 83 ) for placing it against the support face of the tangential arm on the tappet ( 23 ). 
     
     
         4 . The system for coupling a piston according to  claim 1 , wherein the hydraulic piston ( 13 ) comprises—on the side of the tappet ( 18 ) guided by the hydraulic piston—a ball joint ( 17 ) for supporting the tappet on the hydraulic piston from which the orifice ( 307 ) of the connection shaft begins, which ball joint ( 17 ) cooperates with a ball joint ( 20 ) for supporting the hydraulic piston on the tappet and arranged on the tappet ( 18 ) guided by the hydraulic piston, and that the connection shaft ( 301 ) exits from this ball joint ( 20 ). 
     
     
         5 . The system for coupling a piston according to  claim 4 , wherein the connection shaft ( 301 ) is housed in the orifice ( 307 ) of the connection shaft with a play sufficient for allowing an oil to pass which lubricates the tappet support ball joint ( 17 ) on the hydraulic piston at the level of the contact which the latter forms with the support ball joint ( 20 ) of the hydraulic piston on the tappet.