Eccentric Radial Piston Pump and Eccentric Radial Piston Motor

Abstract

In an eccentric radial piston pump, a rib 12 protruded in a radial direction is formed on an inner peripheral surface of an end portion on a discharge side of an eccentric cam ring 3 over a prescribed range. In an eccentric radial piston motor, a rib 12 protruded in a radial direction is formed on an inner peripheral surface of an end portion on a high pressure side of an eccentric cam ring 3 over a prescribed range. By the rib 12 formed in the radial direction, a rigidity of the eccentric cam ring 3 can be improved, and the eccentric cam ring can be prevented from being deformed by a thrust from the piston. Thus, the rigidity of the eccentric cam ring can be increased without increasing the thickness of the eccentric cam ring, and further the eccentric radial piston pump and the eccentric radial piston motor in which outside dimensions in the radial direction are reduced can be provided.

1 . An eccentric radial piston pump in which a displacement volume of pressure oil is changed in accordance with an eccentric amount of an eccentric cam ring, wherein
 the eccentric cam ring is slidably disposed between a pair of guiding surfaces which are opposingly disposed inside a casing of the eccentric radial piston pump, and   a rib protruded in a radial direction is disposed on an inner peripheral surface of an end portion on a discharge side of the eccentric cam ring over a prescribed range.   
   
   
       2 . The eccentric radial piston pump according to  claim 1 , wherein the rib is disposed covering an entire inner periphery of the inner peripheral surface of the end portion. 
   
   
       3 . The eccentric radial piston pump according to  claim 1  or  2 , wherein a thickness of the eccentric cam ring is approximately equal to that of the rib. 
   
   
       4 . The eccentric radial piston pump according to  claim 1  or  2 , wherein a rotation stop engaging member being used when the eccentric cam ring is made eccentric and/or an engaging member engaging an operative mechanism which imparts the eccentric amount to the eccentric cam ring is/are provided on an outer side surface of the rib which is parallel to an eccentric direction of the eccentric cam ring. 
   
   
       5 . The eccentric radial piston pump according to  claim 3 , wherein a rotation stop engaging member being used when the eccentric cam ring is made eccentric and/or an engaging member engaging an operative mechanism which imparts the eccentric amount to the eccentric cam ring is/are provided on an outer side surface of the rib which is parallel to an eccentric direction of the eccentric cam ring. 
   
   
       6 . An eccentric radial piston motor in which a displacement volume of pressure oil is changed in accordance with an eccentric amount of an eccentric cam ring, wherein
 the eccentric cam ring is slidably disposed between a pair of guiding surfaces which are opposingly disposed inside a casing of the eccentric radial piston motor, and   a rib protruded in a radial direction is provided on an inner peripheral surface of an end portion on a high-pressure side of the eccentric cam ring over a prescribed range.   
   
   
       7 . The eccentric radial piston motor according to  claim 6 , wherein the rib is disposed covering an entire inner periphery of the inner peripheral surface of the end portion. 
   
   
       8 . The eccentric radial piston motor according to  claim 6  or  7 , wherein a thickness of the eccentric cam ring is approximately equal to that of the rib. 
   
   
       9 . The eccentric radial piston motor according to  claim 6  or  7 , wherein a rotation stop engaging member being used when the eccentric cam ring is made eccentric and/or an engaging member engaging an operative mechanism which imparts the eccentric amount to the eccentric cam ring is/are provided on an outer side surface of the rib which is parallel to an eccentric direction of the eccentric cam ring. 
   
   
       10 . The eccentric radial piston motor according to  claim 8 , wherein a rotation stop engaging member being used when the eccentric cam ring is made eccentric and/or an engaging member engaging an operative mechanism which imparts the eccentric amount to the eccentric cam ring is/are provided on an outer side surface of the rib which is parallel to an eccentric direction of the eccentric cam ring.