US 5,896,887 AGranted

Pinch tube tank level control valve with snap-action shutoff

AssigneeGeorge S. Cole & Associates, Incorporated

InventorHarry W. Edwards

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Abstract

A liquid level control apparatus for a flush tank includes an upstanding fill tube integral at its upper end with a valve housing carrying a flexible resilient pinch tube valve member and a pivoting actuator engageable with the pinch tube for opening and closing the valve. The valve housing is fixed to a head member defining a conduit which communicates with a downwardly extending tube parallel to the fill tube. A float has cylindrical portions respectively receiving the fill tube and the downwardly extending tube therethrough so that the float can slide upwardly and downwardly along the tubes as the water level in the tank varies. The actuator is pivotally connected to a linkage which extends outwardly through an aperture in the float and is pivotally connected to the float externally thereof. In one embodiment the aperture defines cam surfaces which engage the linkage to operate the actuator. In another embodiment the float carries a control mechanism including a cam slot engageable with a cam follower roller on the linkage for arresting upward movement of the float until the tank is full to provide a snap-action shutoff of the valve.

Claims13

Dependent claims

A liquid level control apparatus for a flush tank containing liquid varying between highest and lowest levels and including a fill tube communicating with the tank and with a source of liquid under pressure, said apparatus comprising:

a valve mechanism communicating with the fill tube and operable between open and closed conditions relative to the fill tube,
a float disposed in the liquid in the tank for movement in response to changes in the liquid level in the tank, and
an actuator linkage coupled to said valve mechanism and to said float for actuating said valve mechanism between its open and closed conditions in response to movement of the float,
said linkage including a control mechanism having a first arresting portion integral with the float and a second arresting portion coupled to the valve mechanism for effecting movement of said valve mechanism,
said control mechanism being responsive to rising of the float to a predetermined stop level intermediate the highest and lowest levels for moving to a stop condition with said second arresting portion engaging said first arresting portion for mechanically arresting further upward movement of the float irrespective of continued rise of the liquid level in the tank,
said control mechanism, when in the stop condition, being responsive to a predetermined buoyancy force exerted on the arrested float when the liquid has risen substantially to the highest level for shifting to a release condition by disengagement of the second arresting portion from the first arresting portion for releasing the float and permitting the arrested float and the linkage to move suddenly to actuate the valve mechanism to its closed condition.

3 more elements

A liquid level control apparatus for a flush tank containing liquid varying between highest and lowest levels and including an upstanding fill tube disposed in the tank and communicating with a source of liquid under pressure, said apparatus comprising:

a valve mechanism communicating with the fill tube and operable between open and closed conditions relative to the fill tube,
a float disposed in the liquid in the tank for movement in response to changes in the liquid level in the tank having a peripheral wall defining a hollow interior space and having a cylindrical portion receiving the fill tube coaxially therethrough for movement relative to the fill tube in response to changes in the liquid level in the tank, and
an actuator linkage coupled to said valve mechanism and connected to said float externally thereof,
said peripheral wall of said float having an aperture therein through which said actuator linkage extends,
said linkage including a control mechanism having a first arresting portion integral with the float and a second arresting portion coupled to the valve mechanism for effecting movement of said valve mechanism,
said control mechanism being responsive to rising of the float to a predetermined stop level intermediate the highest and lowest levels for moving to a stop condition with said second arresting portion engaging said first arresting portion for mechanically arresting further upward movement of the float irrespective of continued rise of the liquid level in the tank,
said control mechanism, when in the stop condition, being responsive to a predetermined buoyancy force exerted on the arrested float when the liquid has risen substantially to the highest level for shifting to a release condition by disengagement of the second arresting portion from the first arresting portion for releasing the float and permitting the arrested float and the linkage to move suddenly to actuate the valve mechanism to its closed condition.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/074,815Filed 8 May 1998 · continuation in part
Priority: 19 Jun 1997
Granted: 27 Apr 1999
Term ends: Not estimatedThe source records don’t support an estimate.

Classification13 codes

E03D 1/32
Valves for high or low level cisterns; Their arrangement ; Flushing mechanisms in the cistern, optionally with provisions for a pre-or a post-…:…
F16K 7/063
By means of a screw-spindle, cam, or other mechanical means: lever clamps
F16K 31/18
Actuated by fluid: actuated by a float
Y10T 137/7387
Quick acting: over center mechanism