Abstract:
A snap action toggle valve actuator assembly for use in a fluid holding tank. Movement of a float or other movable actuating element causes pivotal movement of pivot arm, which compresses a spring. When the float element reaches a predetermined level, the spring causes a downward movement in linkage attached to the rear of a valve actuating lever and an upward movement of a valve rod secured to the other end of the valve actuating lever and vice versa.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a valve actuator assembly used to control the flow of steam, compressed air or other fluids under pressure. It relates particularly to a snap action toggle float valve assembly used to control a pressure powered steam condensate pump. 
     Float valve assemblies have been used for many years to operate either an inlet or an outlet valve in a fluid holding tank. The operating valve is either opened or closed in response to a rise of the fluid to a predetermined level in the fluid holding tank. One well known example of a float valve assembly is used to control the flow of water to refill a toilet tank. 
     Most float valve assemblies are designed to open or close the valve gradually as the level of the fluid in the fluid holding tank raises or lowers. Such a float valve assembly not only slows down the filling or discharge of the fluid in the fluid holding tank bu often causes premature wear to the valve or the valve seat due to the relatively long interval of fluid flow through the valve. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of this invention to provide a valve actuator assembly that provides a quick, positive movement of the valve when the level of the fluid in the fluid holding tank reaches a predetermined level. 
     It is a further object of this invention to provide a valve actuator assembly that is able to operate easily and reliably in a fluid holding tank subject to high pressures and temperatures. 
     It is a still further object of this invention to provide a valve actuator assembly that is easily manufactured and can be adapted to many types of equipment that are controlled by float valves. 
     These and other objects of this invention will become apparent from the accompanying specification, drawings and claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an elevational view, partly in section, of a preferred embodiment of the float valve assembly of this invention where the fluid control valve is in an open position to allow the flow of fluid through the valve. 
     FIG. 2 is an elevational view, partly in section, of a preferred embodiment of the float valve assembly of this invention where the fluid control valve is in a closed position to prevent the flow of fluid through the valve. 
     FIG. 3 is a partial end view to illustrate a portion of the float valve assembly of a preferred embodiment of this invention. 
     FIG. 4 is a schematic diagram to illustrate the relationship and interaction of the components of the valve actuator assembly of this invention where the fluid control valve is in an open position. 
     FIG. 5 is a schematic diagram to illustrate the relationship and interaction of the components of the valve actuator assembly of this invention where the fluid control valve is in a closed position. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     Illustrated in FIGS. 1 and 2, is a preferred embodiment of the valve actuator assembly 1 of this invention used in connection with a float and fluid holding tank 2. As shown in FIGS. 1, 2, and 3, support means 3 in the form of an elongated arm having a pair or spaced, substantially parallel sides 4 is secured to the underside of the top of the tank 2 so that the support means 3 is rigidly suspended from a wall of tank 2 and extends downwardly towards the bottom of the tank. The valve actuator assembly could also be mounted in other arrangements in order to fit other pieces of valve operated equipment. 
     As shown in FIGS. 1 and 2, a float element 5 is secured to the end of a float arm 6 which is pivotally connected to a lower bearing pin 7 which extends between both sides 4 of the support means 3. A substantially U-shaped yoke member 8 having a base 9 and spaced and substantially parallel sides is pivotally connected to an upper bearing pin 10 which extends between both sides 4 of the support means 3 which is more clearly shown in the end view illustrated by FIG. 3. 
     A valve actuating lever 11 is also positioned between the sides 4 or the support means 3 and is pivotally connected to the upper bearing pin 10 also. One end of the valve actuating lever 11 is attached to a valve rod 12 used to open and close the valve 13. A pivot arm 14 is pivotally connected to the sides of the U-shaped yoke member 8 by a pivot arm bearing pin 15 extending through the sides of the U-shaped yoke member 8 adjacent to the base 9. 
     A first spring retainer 16 is pivotally connected one end of the pivot arm 14 and a link 17 or pair of spaced parallel link elements is pivotally connected to the other end of the pivot arm 14 and to one end of the valve actuating lever 11. A compression spring 18 is mounted between the first spring retainer 16 and a second spring retainer 19 secured to the U-shaped yoke member 8. The second spring retainer 19 is preferably adjustable to adjust the compressive force on the compression spring 18. 
     As shown in FIGS. 1 and 2, a toggle actuation arm 20 has one end thereof pivotally connected to the float arm 6 between the float element 5 and the lower bearing pin 7, and the other end of the toggle actuation arm 20 is connected to the pivot arm bearing pin 15 on the U-shaped yoke member 8. 
     FIG. 1 illustrates the float valve assembly of this invention in a fluid holding tank 2, such as may be incorporated with a pump, where the level of the fluid in the tank is low and the float element 5 is in a down position. In this example, when the float element 5 is in a down position the valve 13 is open. 
     FIG. 2 illustrates the float valve assembly of this invention in a fluid holding tank 2, such as may be incorporated with a pump, where the level of the fluid in the tank is high and the float element 5 is in an up position. In this example, when the float element 5 is in a an up position the valve 13 is closed. 
     The pivoted connections between the various components of the valve actuator assembly of this invention provide a smooth, trouble free operation even under severe conditions and high tank pressures and temperatures. The valve actuator assembly of this invention provides for a quick, snap action to the valve actuating lever 11 and to the valve rod 12 itself and produces a quick, positive opening or closing of the valve 13 itself. 
     This quick, positive snap action is the result of the interaction of the various components of the valve actuator assembly 1 that can be further illustrated by FIGS. 4 and 5. 
     FIG. 4 is a schematic diagram to illustrate the valve actuator assembly 1 shown in FIG. 1 where the float element 5 is down and the valve 13 is open. Element AB is the valve actuating lever 11, element BC is the link or links 17, element CE is the pivot arm 14, and element AD is the U-shaped yoke member 8. The compression spring 18 and its end retainers 16 and 19 are shown as element EF. As the float 5 rises it produces an upward movement in the toggle arm 20 and the U-shaped yoke member 8 and causes the pivot arm 14 to compress the spring 18. Further upward movement will cause the link or links 17 (Element BC) to become axially aligned with the valve actuating lever 11 (Element AB). Any further upward movement of the U-shaped yoke member 8 by toggle arm 20 allows the compression spring 18 (Element EF) to expand and thereby force the back end of the valve actuating lever 11 and the link or links 17 downwardly as shown in FIG. 5 causing an upward movement in the valve rod 12 and a closing of the valve 13. It will also be apparent to one skilled in this art that the valve actuator assembly of this invention will operate equally well in a reverse direction such as when the float Element J moves from an up position to a down position, and can be used to operate a plurality of valves instead of the single valve shown in the preferred embodiment. 
     While I have illustrated one preferred embodiment of this invention it is understood that the valve actuator assembly of this invention can be adapted to a number of different situations where a quick, positive snap movement of the valve is needed or required.