Patent Application
20080053536
The following detailed description of the invention is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description of the invention.
The support bar 124 extends radially across and axially along the valve body 112 separating the flow channels 142, 144. Preferably, the support bar 124 and valve body 112 are configured to maximize the inlet cross sectional flow area relative to the upstream face 136. In one embodiment, the inlet cross sectional flow area comprises at least 75% of the area of the valve body upstream face 136. Maximization of the inlet cross sectional flow area allows the valve 110 to respond to pressure changes that are less than about 1 psi. In one embodiment, the inlet cross sectional flow area is further maximized by including a tapered upstream edge 146 along a radial length of the support bar 124. The upstream edge 146 may be v-shaped or beveled. Additionally, the upstream edge 146 may or may not be substantially flush with the valve body upstream face 136.
The valve body 112 also includes a valve seat 148 located on its downstream face 140. As will be discussed later, the valve seat 148 is configured to provide a surface with which the flappers 118, 120 selectively contact to seal and unseal the valve 110. The two stop supports 126, 128 extend axially from the valve body 112 and are generally spaced equally apart from one another. Preferably, the stop supports 126, 128 each have an axial length that is less than about 50% of the radius of the valve body 112. The stop supports 126, 128 include two pairs of mount holes 150, 152 for mounting the shaft 114 and stop mechanism 116, respectively.
As alluded to above, the flappers 118, 120 are rotationally mounted to the valve body 112, preferably via the shaft 114 and selectively seal and unseal the flow channels 142, 144. Preferably, the flappers 118, 120 are configured such that a minimal amount of air leaks across the valve 110 when the flow channels 142, 144 are sealed. In this regard, the magnitude of force that is needed to cause the flappers 118, 120 to seal the valve seat 148 is preferably minimized. In one embodiment, contact pressure between the flappers 118, 120 and valve seat 148 is increased by minimizing contact area therebetween. For example, the flappers 118, 120 and valve seat 148 may be configured such that the contact area between the flapper 118, 120 and valve body 112 is reduced by 50% as compared to prior art configurations, thereby doubling the contact pressure and improving valve sealing.
Each flapper 118, 120 preferably includes one or more protrusions that extend from downstream faces 155, 157 thereof and that are configured to contact the stop mechanism 116. In one exemplary embodiment depicted in
In some embodiments, the flappers 118, 120 may be biased toward the closed position and may each be coupled to one or more torsion springs (not shown). The torsion springs supply a predetermined torsional force that urges the flappers 118, 120 toward the closed position to thereby seal the flow channels 142, 144. When the differential pressure magnitude exceeds a predetermined value and overcomes the torsional force, the flappers 118, 120 move to an open position to unseal the flow channels 142, 144. Preferably, the predetermined value is a pressure that can be withstood by the inlet duct 104 and the outlet duct 106 without compromising their structural integrity and that can be detected by the valve 110.
A split flapper check valve has now been provided that can detect pressure differentials that may be lower than about 1 psi. In addition, the split flapper check valve is lightweight and relatively inexpensive to implement. Moreover, the valve is easily implemented into existing systems.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt to a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.
