Pump with quick discharge function

Abstract

A pump includes a chamber defined by a piston movable in a body comprising an intake opening able to communicate with the chamber and a first non-return member authorizing passage of fluid from the opening toward the chamber, and prohibiting the passage from the chamber toward the opening. An expulsion opening is between the chamber and a duct, and a second non-return member authorizes passage of fluid from the chamber toward the duct, and prohibits passage from the duct toward the chamber. The body includes a discharge opening communicating with the duct and able to communicate with the opening, and a third non-return member movable between an open position, in which the duct communicates with the opening, and a closed position prohibiting the passage of fluid between the duct and the opening. The pump includes a member to move the third non-return member.

1 . A pump including a hollow body and a piston housed in the hollow body movably in a longitudinal direction, the piston defining, with the hollow body, a compression chamber with a variable volume depending on a position of the piston in the longitudinal direction, the hollow body including:
 an intake opening designed to communicate with a fluid source and able to communicate with the compression chamber;   a first non-return member arranged between the intake opening and the compression chamber to allow the passage of fluid from the intake opening to the compression chamber, and to prohibit the passage of fluid from the compression chamber to the intake chamber;   an expulsion opening emerging in the compression chamber and communicating with an expulsion duct;   a second non-return member arranged between the compression chamber and the expulsion duct to allow the passage of fluid from compression chamber to the expulsion duct, and to prohibit the passage of fluid from the expulsion duct to the compression chamber; and wherein:   the hollow body includes a discharge opening communicating with the expulsion duct and able to communicate with the intake opening, and a third non-return member movable between an open position, in which the expulsion duct communicates with the intake opening, and a closed position prohibiting the passage of fluid between the expulsion duct and the intake opening, and   the pump includes displacement elements for moving the third non-return member.   
     
     
         2 . The pump according to  claim 1 , wherein the displacement elements include:
 a ferromagnetic element movable between a first position, in which the third non-return member is in the open position, and a second position, in which the third non-return member is in the closed position,   a first elastic member biasing the ferromagnetic element toward its first position, and   an electric coil, surrounding the ferromagnetic element and electrically connected to a power supplier able to apply an adjustable current, wherein a position of the ferromagnetic element depends on voltage of the current.   
     
     
         3 . The pump according to  claim 2 , wherein:
 the third non-return member includes a non-return gate biased in the closed position by a third elastic member, and the displacement elements include an actuating element secured to the piston and designed to cooperate with the non-return gate to move the non-return gate into the open position by pushing the non-return gate against the biasing of the third elastic member, and when the piston is in a predetermined discharge position,   said ferromagnetic element is formed by a rod secured to the piston.   
     
     
         4 . The pump according to  claim 3 , wherein the piston is movable, in the longitudinal direction, between:
 a first extreme position, in which the actuating element cooperates with the non-return gate, and in which the volume of the compression chamber is maximal,   a second extreme position, in which the volume of the compression chamber is minimal, and   at least one intermediate position, in which the actuating element is kept at a distance from the non-return gate.   
     
     
         5 . The pump according to  claim 2 , wherein the third non-return member includes a non-return gate, said ferromagnetic element being formed by the non-return gate. 
     
     
         6 . The pump according to  claim 1 , wherein the piston includes a rod made from a ferromagnetic material and extending in the longitudinal direction, the pump including an electric coil surrounding the rod of the piston and electrically connected to a power supplier able to apply a variable electric current, wherein a position of the piston depends on voltage of the electric current. 
     
     
         7 . The pump according to  claim 1 , wherein the intake opening includes a filter. 
     
     
         8 . The pump according to  claim 1 , including a variable volume fluid reservoir forming the fluid source. 
     
     
         9 . The pump according to  claim 1 , wherein the fluid is gas, in particular air. 
     
     
         10 . An assembly of a pump and a pressure-sensitive controllable element controlled by the pump, wherein the pump includes a hollow body and a piston housed in the hollow body movably in a longitudinal direction, the piston defining, with the hollow body, a compression chamber with a variable volume depending on a position of the piston in the longitudinal direction, the hollow body including:
 an intake opening designed to communicate with a fluid source and able to communicate with the compression chamber;   a first non-return member arranged between the intake opening and the compression chamber to allow the passage of fluid from the intake opening to the compression chamber, and to prohibit the passage of fluid from the compression chamber to the intake chamber;   an expulsion opening emerging in the compression chamber and communicating with an expulsion duct;   a second non-return member arranged between the compression chamber and the expulsion duct to allow the passage of fluid from compression chamber to the expulsion duct, and to prohibit the passage of fluid from the expulsion duct to the compression chamber; and wherein:   the hollow body includes a discharge opening communicating with the expulsion duct and able to communicate with the intake opening, and a third non-return member movable between an open position, in which the expulsion duct communicates with the intake opening, and a closed position prohibiting the passage of fluid between the expulsion duct and the intake opening, and   the pump includes displacement elements for moving the third non-return member, and wherein the controllable element is connected to the expulsion duct of the pump.   
     
     
         11 . The assembly according to  claim 10 , wherein the controllable element includes a movable membrane of an expansion vessel equipping a Rankine system, said Rankine system comprising:
 an evaporator,   a steam machine arranged downstream from the evaporator,   a condenser arranged downstream from the steam machine,   a pumping device arranged downstream from the condenser, and   the expansion vessel being arranged between the condenser and the pumping device, the expansion vessel including:
 an enclosure, 
 said movable membrane, mounted movably in the enclosure and separating the enclosure into a first part communicating with the condenser and the pumping device, and a second part communicating with the expulsion duct of the pump. 
   
     
     
         12 . The assembly according to  claim 10 , wherein the controllable element is a valve actuator, in particular for a motor vehicle exhaust device.