Bidirectional pump with diaphragm operated valve for dishwasher
First Claim
1. a liquid control structure for controlling delivery of liquid from a supply selectively to either of first and second points of use, said structure comprising:
- a first conduit having a first outlet adapted to be disposed in communication with a first point of use;
a second conduit having a second outlet adapted to be disposed in communication with a second point of use;
means for delivering liquid selectively to either of said first and second conduits,said second conduit having an associated port through which liquid from the delivering means flows in moving toward said second point of use and a flat sealing edge around the port;
stopper means responsive to a differential in the pressure of liquid respectively in the first and second conduits to be disposed (a) in a first position for preventing delivery of liquid through the second conduit to said second outlet and (b) in a second position for permitting delivery of liquid through the second conduit to said second outlet,said stopper means comprising a collapsible diaphragm having a wall with substantially flat, oppositely facing surfaces with one of said oppositely facing surfaces directly exposed to liquid directed by the liquid delivering means through the first conduit and the other of said oppositely facing surfaces directly exposed to liquid directed by the liquid delivering means through the second conduit and urged sealingly against the edge around the second conduit port with the stopper means in its first position,said diaphragm in said first position being extended and in said second position being collapsed;
a rigid forming member with a flat surface;
means mounting the forming member to the diaphragm so that the flat surface of the forming member is facially engaged with the one of the oppositely facing surfaces on the wall of the diaphragm; and
means normally biasing the flat surface of the forming member against the diaphragm wall and in turn the other of the oppositely facing diaphragm wall surfaces sealingly against the edge around the second conduit port toward the first position of said stopper means,whereby with the liquid pressure in the first conduit in conjunction with the biasing means develops a force on the one of the oppositely facing wall surfaces to urge the diahragm into said first, extended position, and with the liquid pressure in the second conduit a predetermined amount greater than the liquid pressure in the first conduit the liquid in the second conduit develops a force on the other of the oppositely facing wall surfaces to overcome the force developed by the biasing means and urge the diaphragm into said second, collapsed position.
1 Assignment
0 Petitions
Accused Products
Abstract
A bidirectional pump has a chamber in communication both with a drain conduit and a conduit for delivering washing liquid into a wash chamber. The drain conduit has a port communicating between the pump chamber and a drain outlet. An opening communicates between the delivery and drain conduits and is selectively sealed by a deformable diaphragm. With the pump rotating in a first direction and the liquid being delivered principally through the delivery conduit by the pump, a pressure differential is established across the diaphragm thereby urging a portion of the diaphragm sealingly against the port to prevent delivery of washing liquid through the drain conduit as during a rinsing cycle of the dishwasher. Reverse rotation of the pump reverses the pressure balance to urge the sealing portion of the diaphragm away from the drain port, thereby permitting flow through the drain conduit for suitable disposal of the used washing liquid.
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Citations
15 Claims
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1. a liquid control structure for controlling delivery of liquid from a supply selectively to either of first and second points of use, said structure comprising:
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a first conduit having a first outlet adapted to be disposed in communication with a first point of use; a second conduit having a second outlet adapted to be disposed in communication with a second point of use; means for delivering liquid selectively to either of said first and second conduits, said second conduit having an associated port through which liquid from the delivering means flows in moving toward said second point of use and a flat sealing edge around the port; stopper means responsive to a differential in the pressure of liquid respectively in the first and second conduits to be disposed (a) in a first position for preventing delivery of liquid through the second conduit to said second outlet and (b) in a second position for permitting delivery of liquid through the second conduit to said second outlet, said stopper means comprising a collapsible diaphragm having a wall with substantially flat, oppositely facing surfaces with one of said oppositely facing surfaces directly exposed to liquid directed by the liquid delivering means through the first conduit and the other of said oppositely facing surfaces directly exposed to liquid directed by the liquid delivering means through the second conduit and urged sealingly against the edge around the second conduit port with the stopper means in its first position, said diaphragm in said first position being extended and in said second position being collapsed; a rigid forming member with a flat surface; means mounting the forming member to the diaphragm so that the flat surface of the forming member is facially engaged with the one of the oppositely facing surfaces on the wall of the diaphragm; and means normally biasing the flat surface of the forming member against the diaphragm wall and in turn the other of the oppositely facing diaphragm wall surfaces sealingly against the edge around the second conduit port toward the first position of said stopper means, whereby with the liquid pressure in the first conduit in conjunction with the biasing means develops a force on the one of the oppositely facing wall surfaces to urge the diahragm into said first, extended position, and with the liquid pressure in the second conduit a predetermined amount greater than the liquid pressure in the first conduit the liquid in the second conduit develops a force on the other of the oppositely facing wall surfaces to overcome the force developed by the biasing means and urge the diaphragm into said second, collapsed position. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A bidirectional pump for delivering washing liquid into a wash chamber of a dishwashing apparatus, said pump comprising:
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a housing defining an impeller chamber; means for introducing liquid from a supply into said impeller chamber; an impeller in said impeller chamber; a liquid delivery conduit communicating between the impeller chamber and the wash chamber; a drain conduit communicating between the impeller chamber and a drain outlet; means for selectively rotating the impeller in opposite directions, said impeller directing liquid in said impeller chamber principally into the delivery conduit when rotated in a first direction and directing liquid in said impeller chamber principally into the drain conduit when rotated oppositely to the first direction; means for sensing a pressure differential between the delivery and drain conduits and movable (a) to a first position to prevent flow of liquid through the drain conduit to the drain outlet and (b) to a second position wherein liquid can flow through the drain conduit to the drain outlet, said sensing means comprising a collapsible cup-shaped diaphragm with an annular body and a bottom wall having one surface thereon exposed to liquid in the liquid delivery conduit and an oppositely facing surface thereon exposed to liquid in the drain conduit, said diaphragm collapsing with the liquid pressure on the oppositely facing bottom wall surface greater than the pressure on the one bottom wall surface; a rigid forming member with a flat surface; means mounting the forming member to the diaphragm so that the flat surface of the forming member is facially engaged with the one of the oppositely facing surfaces on the wall of the diaphragm; and biasing means for urging said forming member against said diaphragm bottom wall, whereby with the liquid pressure in the first conduit in conjunction with the biasing means develops a force on the one of the oppositely facing wall surfaces to urge the diaphragm into said first, extended position, and with the liquid pressure in the second conduit a predetermined amount greater than the liquid pressure in the first conduit the liquid in the second conduit develops a force on the other of the oppositely facing wall surfaces to overcome the force developed by the biasing means and urge the diaphragm into said second, collapsed position. - View Dependent Claims (11, 12, 13, 14, 15)
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Specification