Piston pump for a high-pressure cleaning appliance

Abstract

A piston pump for a high-pressure cleaning appliance is provided, including a plurality of pump chambers, into each of which one piston which is movable back and forth plunges, and which are each in flow connection via a suction valve with a suction inlet and via a pressure valve with a pressure outlet, the suction valve including a suction valve closing member which is sealingly positionable on a suction valve seat, and the pressure valve including a pressure valve closing member which is sealingly positionable on a pressure valve seat, the pressure valve seat and the suction valve seat being at different radial distances from a longitudinal pump axis. To increase piston pump mechanical stability without increasing material thickness, the pressure valve seat can be arranged, in relation to the longitudinal pump axis, offset from the suction valve seat in the circumferential direction of the piston pump.

1 . A piston pump for a high-pressure cleaning appliance, comprising a plurality of pump chambers, into each of which one piston which is movable back and forth plunges, and which are each in flow connection via a suction valve with a suction inlet and via a pressure valve with a pressure outlet, the suction valve comprising a suction valve closing member which is sealingly positionable on a suction valve seat, and the pressure valve comprising a pressure valve closing member which is sealingly positionable on a pressure valve seat, the pressure valve seat and the suction valve seat being at different radial distances from a longitudinal pump axis, and the pressure valve seat being arranged, in relation to the longitudinal pump axis, offset from the suction valve seat in the circumferential direction of the piston pump. 
     
     
         2 . The piston pump in accordance with  claim 1 , wherein the pressure valve seat is arranged, in relation to the longitudinal pump axis, offset at an angle of 10° to 40° from the suction valve seat. 
     
     
         3 . The piston pump in accordance with  claim 1 , wherein the pressure valve seat is arranged, in relation to the longitudinal pump axis, at the same level as the suction valve seat in the axial direction. 
     
     
         4 . The piston pump in accordance with  claim 1 , wherein the piston pump comprises three suction valve seats arranged so as to be uniformly distributed about the longitudinal pump axis and three pressure valve seats arranged so as to be uniformly distributed about the longitudinal pump axis. 
     
     
         5 . The piston pump in accordance with  claim 1 , wherein the piston pump comprises a pump block and a pump head, the pump head comprising the suction inlet and the pressure outlet, and the pump block comprising the pump chambers and accommodating the suction valves and the pressure valves, and the pump head being fitted on a triangular rim of the pump block, the suction valves, in a plan view of the pump block, being arranged in the corner areas of the rim, and the pressure valves, in a plan view of the pump block, being surrounded by a cylindrical inside wall within the rim. 
     
     
         6 . The piston pump in accordance with  claim 1 , wherein the suction valves each comprise a suction valve passage which is closable by the suction valve closing member, and a suction valve closing spring which acts upon the suction valve closing member with a spring force in the direction of the suction valve passage, the suction valve closing spring being positioned at an axial distance from the suction valve passage. 
     
     
         7 . The piston pump in accordance with  claim 6 , wherein the suction valve closing spring is arranged in a suction valve chamber which is in flow connection with a pump chamber via the suction valve passage, a retaining arm, on which the suction valve closing spring is supported, projecting into the suction valve chamber at an axial distance from the suction valve passage. 
     
     
         8 . The piston pump in accordance with  claim 7 , wherein the retaining arm forms a guide for the suction valve closing member. 
     
     
         9 . The piston pump in accordance with  claim 7 , wherein the retaining arm comprises a through-opening through which the suction valve closing member passes. 
     
     
         10 . The piston pump in accordance with  claim 9 , wherein the suction valve closing spring is clamped on the side of the retaining arm that faces away from the suction valve passage between the retaining arm and the suction valve closing member.