Gravity-assisted fluid pump

Abstract

A gravity-assisted fluid pump includes a fluid reservoir, a piston, a valve element, a piston operator, and a valve operator. The piston is movably disposed within the fluid reservoir and is movable between an uppermost position and a lowermost position. The valve element is movable between a closed position and an open position. The piston operator moves the piston between the uppermost position and the lowermost position. The valve operator selectively moves the valve element between the closed position and an open position.

1 . A fluid pump, comprising:
 a fluid reservoir including an inner surface that defines a fluid volume for receiving a fluid;   a piston movably disposed within the fluid reservoir against the inner surface and dividing the fluid volume into an upper variable fluid volume and a lower variable fluid volume, the piston movable between an uppermost position and a lowermost position and including an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides;   a valve element movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume;   a piston operator coupled to the piston, the piston operator responsive to an input force to move the piston to the uppermost position and the lowermost position; and   a valve operator coupled to the valve element and operable to selectively move the valve element to the closed position and an open position.   
   
   
       2 . The pump of  claim 1 , further comprising:
 a piston actuator coupled to the piston operator and operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position.   
   
   
       3 . The pump of  claim 2 , wherein:
 the piston operator comprises a rod coupled to the piston upper surface and extending upwardly therefrom to an upper end; and   the piston actuator is coupled to the rod upper end.   
   
   
       4 . The pump of  claim 3 , further comprising:
 a support bearing assembly surrounding, and providing lateral support for, the rod.   
   
   
       5 . The pump of  claim 3 , wherein:
 the rod is hollow; and   the valve operator comprises a shaft extending through the rod and having a lower end coupled to the valve element.   
   
   
       6 . The pump of  claim 1 , further comprising:
 a valve actuator coupled to the valve operator and operable to selectively supply an actuation force thereto that moves the valve element to the closed position and an open position.   
   
   
       7 . The pump of  claim 1 , further comprising:
 a discharge conduit having an inlet and an outlet, the discharge conduit inlet in fluid communication with the lower variable fluid volume, the discharge conduit outlet disposed at a position above the upper variable fluid volume.   
   
   
       8 . The pump of  claim 7 , further comprising:
 a check valve disposed within the discharge conduit between the discharge conduit inlet and outlet.   
   
   
       9 . The pump of  claim 1 , wherein the fluid reservoir includes a fluid inlet adapted to receive fluid from a fluid source. 
   
   
       10 . The pump of  claim 1 , wherein the upper variable fluid volume is larger than the lower variable fluid volume, regardless of the position of the piston. 
   
   
       11 . A fluid pump system, comprising:
 a fluid reservoir including an inner surface that defines a fluid volume for receiving a fluid;   a piston movably disposed within the fluid reservoir against the inner surface and dividing the fluid volume into an upper variable fluid volume and a lower variable fluid volume, the piston movable between an uppermost position and a lowermost position and including an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides;   a valve element movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume;   a piston operator coupled to the piston, the piston operator responsive to an input force to move the piston to the uppermost position and the lowermost position;   a valve operator coupled to the valve element and operable to selectively move the valve element to the closed position and an open position;   a piston actuator coupled to the piston operator and operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position;   a valve actuator adapted to receive actuator control signals and operable, in response thereto, to selectively supply an actuation force to the valve operator to move the valve element to the closed position and an open position; and   a valve actuator control operable to supply the actuator control signals to the valve actuator, the valve actuator control configured to supply actuator control signals that cause the valve element to be moved to (i) the open position when the piston is in the lowermost position and (ii) the closed position when the piston is in the uppermost position.   
   
   
       12 . The pump of  claim 11 , wherein:
 the piston operator comprises a rod coupled to the piston upper surface and extending upwardly therefrom to an upper end; and   the piston actuator is coupled to the rod upper end.   
   
   
       13 . The pump of  claim 12 , further comprising:
 a support bearing assembly surrounding, and providing lateral support for, the rod.   
   
   
       14 . The pump of  claim 12 , wherein:
 the rod is hollow; and   the valve operator comprises a shaft extending through the rod and having a lower end coupled to the valve element.   
   
   
       15 . The pump of  claim 11 , further comprising:
 a discharge conduit having an inlet and an outlet, the discharge conduit inlet in fluid communication with the lower variable fluid volume, the discharge conduit outlet disposed at a position above the upper variable fluid volume.   
   
   
       16 . The pump of  claim 7 , further comprising:
 a check valve disposed within the discharge conduit between the discharge conduit inlet and outlet.   
   
   
       17 . The pump of  claim 1 , wherein the fluid reservoir includes a fluid inlet adapted to receive fluid from a fluid source. 
   
   
       18 . The pump of  claim 1 , wherein the upper variable fluid volume is larger than the lower variable fluid volume, regardless of the position of the piston. 
   
   
       19 . A fluid pump, comprising:
 a fluid reservoir including a fluid inlet, a fluid outlet, and an inner surface that defines a fluid volume for receiving fluid;   a piston movably disposed within the fluid reservoir against the inner surface and dividing the fluid volume into an upper variable fluid volume and a lower variable fluid volume, the piston movable between an uppermost position and a lowermost position and including an upper side exposed to the upper variable fluid volume, a lower side exposed to the lower variable fluid volume, and an aperture extending between the upper and lower sides;   a valve element movable between a closed position, in which the valve element seals the aperture to thereby fluidly isolate the upper variable fluid volume from the lower variable fluid volume, and an open position, in which the valve element does not seal the aperture to thereby fluidly communicate the upper variable fluid volume with the lower variable fluid volume;   a piston rod coupled to the piston upper surface and extending upwardly therefrom to an upper end, the piston rod responsive to an input force to move the piston to the uppermost position and the lowermost position;   a valve operator coupled to the valve element;   a piston actuator coupled to the piston rod and operable to selectively supply the input force thereto that moves the piston to the uppermost position and the lowermost position;   a valve actuator coupled to the valve operator and operable to selectively supply an actuation force thereto that moves the valve element to the closed position and an open position; and   a discharge conduit having an inlet and an outlet, the discharge conduit inlet in fluid communication with the lower variable fluid volume via the fluid reservoir fluid outlet, the discharge conduit outlet disposed at a position above the upper variable fluid volume.   
   
   
       20 . The pump of  claim 19 , further comprising:
 a check valve disposed within the discharge conduit between the discharge conduit inlet and outlet.