Fluid control system

Claim 2

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed; fluid recirculation means for spraying washing fluid into said chamber to remove particles from articles contained therein; large mesh first stage filter means for removing large particles from said fluid; fine mesh second stage filter means for removing relatively fine particles from the large mesh filtered fluid; auxiliary spray means associated with said fine mesh filter means for removing filtered particles from said fine mesh filter means; a first fluid egress from said chamber for withdrawing fine mesh filtered fluid from said chamber; a second fluid egress from sAid chamber for withdrawing large mesh filtered fluid from said chamber; first pump means having an inlet communicating with said first fluid egress and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable in first and second directions for supplying fine mesh filtered fluid to said fluid recirculation means and said auxiliary spray means; second pump means communicating with said second fluid egress and an external drain and operable in one of said directions for removing large mesh filtered fluid from said chamber and pumping it toward said external drain; reversible drive means drivingly connected to said first and second pump means; and means controlling said drive means for effecting common rotation of said first and second pump means selectively in said first and second directions.

Claim 3

In a dishwashing apparatus as defined in claim 1 wherein said first and second egresses are in the form of first and second fluid conduits independently and separately connected to said lower portion of the washing chamber.

Claim 4

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed and having a sump in a lower portion thereof; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; large mesh filter means for removing relatively large particles from the washing fluid; fine mesh filter means for removing relatively fine particles from the washing fluid; auxiliary spray means for effecting cleaning of said fine mesh filter means; a first fluid conduit for receiving fine mesh filtered fluid from said sump; a second fluid conduit for receiving large mesh filtered fluid from said sump; first pump means having an inlet communicating with said first fluid conduit and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable in first and second directions for supplying fine mesh filtered fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid conduit and an outlet communicating with a drain conduit and operable in said second direction for maintaining a sufficiently large positive head at said second pump outlet for pumping large mesh fluid from said sump and through said drain conduit toward an external drain; housing means defining pump cavities for said first and second pump means, said second pump means being operable in said first direction for maintaining a positive head at the outlet thereof below a predetermined height in said drain conduit for preventing flow of fluid through said drain conduit and preventing suction of fluid from said drain conduit; reversible drive means attached to said housing means and including a shaft member drivingly connecting said first and second pump means for common rotation thereof; and means controlling said drive means for selectively rotating said first and second pump means in said first and second directions.

Claim 5

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed and having a sump in a lower portion thereof; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; large mesh filter means for removing relatively large particles from the washing fluid; fine mesh filter means for removing relatively fine particles from the washing fluid; auxiliary spray means for effecting cleaning of said fine mesh filter means; a first fluid conduit for receiving fine mesh filtered fluid from said sump; a second fluid conduit for receiving large mesh filtered fluid from said sump; first pump means having an inlet communicating with said first fluid conduit and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable in first and second directions for supplying fine mesh filtered fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid conduit and an outlet communicating with a drain conduit and operable in said second direction for maintaining a sufficiently large positive head at said second pump outlet for pumping large mesh fluid from said sump and through said drain conduit toward an external drain; housing means defining pump cavities for said first and second pump means, said second pump means being operable in said first direction for maintaining a positive head at the outlet thereof below a predetermined height in said drain conduit for preventing flow of fluid through said drain conduit and preventing suction of fluid from said drain conduit; reversible drive means attached to said housing means and including a shaft member drivingly connecting said first and second pump means for common rotation thereof; and means controlling said drive means for selectively rotating said first and second pump means in said first and second directions.

Claim 6

In a dishwashing apparatus as defined in claim 3 wherein said filter means is disposed in said sump for filtering said washing fluids and wherein said auxiliary spray means is disposed within said filter means for backwashing filtered particles from said filter means during rotation of said first pump means in said first and second directions.

Claim 7

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; a first fluid egress from a lower portion of said chamber for conducting washing fluid from said chamber; fine mesh filter means for removing relatively fine particles from the washing fluid passing through said first fluid egress; auxiliary spray means associated with said fine mesh filter means for removing filtered particles from said fine mesh filter meanS; a second egress from a lower portion of said chamber for conducting washing fluid by-passing said fine mesh filter means; large mesh filter means for removing large particles from the fluid passing through said second fluid egress; first pump means having an inlet communicating with said first fluid egress and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable in first and second directions for supplying fine mesh filtered fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid egress and an outlet communicating with a drain conduit and operable in one of said directions for removing large mesh filtered fluid from said chamber and pumping it through said drain conduit toward an external drain; reversible drive means drivingly connected to said first and second pump means; and means controlling said drive means for effecting common rotation of said first and second pump means selectively in said first and second directions.

Claim 8

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; a first fluid egress from a lower portion of said chamber for conducting washing fluid from said chamber; fine mesh filter means for removing relatively fine particles from the washing fluid passing through said first fluid egress; auxiliary spray means associated with said fine mesh filter means for removing filtered particles from said fine mesh filter meanS; a second egress from a lower portion of said chamber for conducting washing fluid by-passing said fine mesh filter means; large mesh filter means for removing large particles from the fluid passing through said second fluid egress; first pump means having an inlet communicating with said first fluid egress and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable in first and second directions for supplying fine mesh filtered fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid egress and an outlet communicating with a drain conduit and operable in one of said directions for removing large mesh filtered fluid from said chamber and pumping it through said drain conduit toward an external drain; reversible drive means drivingly connected to said first and second pump means; and means controlling said drive means for effecting common rotation of said first and second pump means selectively in said first and second directions.

Claim 9

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed and having a sump in a lower portion thereof; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; fine mesh filter means in said sump for removing relatively fine particles from said washing fluid; auxiliary spray means associated with said fine mesh filter means for removing filtered particles therefrom; a first fluid conduit connected to a first portion of said sump for receiving fine mesh filtered fluid; a second fluid conduit connected to a second portion of said sump spaced from said fine mesh filter means for receiving washing fluid and particles therein by-passing said fine mesh filter means; first pump means having an inlet communicating with said first fluid conduit and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable in first and second directions for supplying fine mesh filtered fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid conduit and an outlet communicating with a drain conduit including a portion raised above the outlet of said second pump means and operable in said first direction for maintaining a positive head at said second pump outlet of less than the height of said raised portion for substantially preventing fluid flow through said drain conduit and operable in said second direction for maintaining a positive head at said second pump outlet greater than the height of said raised portion for pumping washing fluid and particles therein from said sump through said drain conduit toward said external drain; reversible motor means operable for effecting common rotation of said first and second pump means; and means controlling said motor means for selectively rotating said first and second pump means in said first and second directions.

Claim 10

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed and having a sump in a lower portion thereof; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; fine mesh filter means in said sump for removing relatively fine particles from said washing fluid; auxiliary spray means associated with said fine mesh filter means for removing filtered particles therefrom; a first fluid conduit connected to a first portion of said sump for receiving fine mesh filtered fluid; a second fluid conduit connected to a second portion of said sump spaced from said fine mesh filter means for receiving washing fluid and particles therein by-passing said fine mesh filter means; first pump means having an inlet communicating with said first fluid conduit and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable in first and second directions for supplying fine mesh filtered fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid conduit and an outlet communicating with a drain conduit including a portion raised above the outlet of said second pump means and operable in said first direction for maintaining a positive head at said second pump outlet of less than the height of said raised portion for substantially preventing fluid flow through said drain conduit and operable in said second direction for maintaining a positive head at said second pump outlet greater than the height of said raised portion for pumping washing fluid and particles therein from said sump through said drain conduit toward said external drain; reversible motor means operable for effecting common rotation of said first and second pump means; and means controlling said motor means for selectively rotating said first and second pump means in said first and second directions.

Claim 11

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed and having a sump in a lower portion thereof; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; large mesh first stage filter means for removing relatively large particles from said fluid; fine mesh second stage filter means in said sump for removing relatively fine particles from the large mesh filtered fluid; auxiliary spray means associated with said fine mesh filter means for removing the filtered particles therefrom; a first fluid conduit connected to a first portion of said sump for receiving fine mesh filtered washing fluid; a second fluid conduit connected to a second portion of said sump spaced from said fine mesh filter means for receiving large mesh filtered fluid and relatively fine particles therein bypassing said fine mesh filter means; first pump means having an inlet communicating with said first fluid conduit and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable for supplying fine mesh filtered washing fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid conduit and an outlet communicating with a drain conduit, said second pump means being operable in said first direction for maintaining a positive head at said second pump outlet below a predetermined height in said drain conduit for substantially preventing fluid flow through and suction from said drain conduit and operable in said second direction for maintaining a positive head at said second pump outlet greater than said predetermined height for pumping large mesh filtered fluid and fine particles therein from said sump and through said drain conduit toward said external drain; housing means defining first and second pump cavities for said first and second pump means; means within said housing means separating said first and second pump cavities while permitting flow of a relatively small quantity of fine mesh filtered fluid from said first pump cavity into said second pump cavity in said first direction of rotation; reversible motor means operable for effecting common rotation of said first and second pump means; and means controlling said motor means for selectively rotating said first and second pump means in said first and second directions.

Claim 12

In a dishwashing apparatus, the combination comprising: a washing chamber for receiving articles to be washed and having a sump in a lower portion thereof; fluid recirculation means for spraying washing fluid into said chamber to remove particles from the articles contained therein; large mesh first stage filter means for removing relatively large particles from said fluid; fine mesh second stage filter means in said sump for removing relatively fine particles from the large mesh filtered fluid; auxiliary spray means associated with said fine mesh filter means for removing the filtered particles therefrom; a first fluid conduit connected to a first portion of said sump for receiving fine mesh filtered washing fluid; a second fluid conduit connected to a second portion of said sump spaced from said fine mesh filter means for receiving large mesh filtered fluid and relatively fine particles therein bypassing said fine mesh filter means; first pump means having an inlet communicating with said first fluid conduit and an outlet communicating with said fluid recirculation means and said auxiliary spray means and operable for supplying fine mesh filtered washing fluid to said fluid recirculation means and said auxiliary spray means; second pump means having an inlet communicating with said second fluid conduit and an outlet communicating with a drain conduit, said second pump means being operable in said first direction for maintaining a positive head at said second pump outlet below a predetermined height in said drain conduit for substantially preventing fluid flow through and suction from said drain conduit and operable in said second direction for maintaining a positive head at said second pump outlet greater than said predetermined height for pumping large mesh filtered fluid and fine particles therein from said sump and through said drain conduit toward said external drain; housing means defining first and second pump cavities for said first and second pump means; means within said housing means separating said first and second pump cavities while permitting flow of a relatively small quantity of fine mesh filtered fluid from said first pump cavity into said second pump cavity in said first direction of rotation; reversible motor means operable for effecting common rotation of said first and second pump means; and means controlling said motor means for selectively rotating said first and second pump means in said first and second directions.