Abstract:
An annular dual-flow check valve for controlling the flow through concentric channels that have a common outlet, comprising: an outer body and an inner body that define the concentric channels, which include an outer channel and an inner channel formed therein; a spring activated annular poppet that resides in the outer channel and has a range of motion in the axial direction; and an opening through the inner body that connects the outer channel to the inner channel; wherein: the axial movement of the annular poppet is regulated by the pressure of the flow upstream of the annular poppet in the outer channel; and the axial range of motion of the annular poppet includes at least two axial positions: a closed position where the annular poppet substantially covers the opening and a open position where at least a portion of the opening is not covered by the annular poppet.

Description:
BACKGROUND OF THE INVENTION 
     This present application relates generally to apparatus, methods and/or systems pertaining to controlling flow through concentric hollow passages. More specifically, but not by way of limitation, the present application relates to apparatus, methods and/or systems pertaining to an annular style check valve that passively controls two independent supply flow streams to a common outlet flow stream. 
     In certain industrial applications, there is a need for controlling the flow of supply lines that are configured in a concentric arrangement and that have a common outlet. While certain conventional systems may be configured to functional perform this tasks, they are bulky, inefficient, expensive and/or require active control. As a result, there remains a need for improved apparatus, methods and/or systems relating to the more efficient and cost effective control of the flows through concentrically arranged supply lines. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The present application thus describes an annular dual-flow check valve for controlling the flow through concentric channels that have a common outlet, comprising: an outer body and an inner body that define the concentric channels, which include an outer channel and an inner channel formed therein; a spring activated annular poppet that resides in the outer channel and has a range of motion in the axial direction; and an opening through the inner body that connects the outer channel to the inner channel; wherein: the axial movement of the annular poppet is regulated by the pressure of the flow upstream of the annular poppet in the outer channel; and the axial range of motion of the annular poppet includes at least two axial positions: a closed position where the annular poppet substantially covers the opening and a open position where at least a portion of the opening is not covered by the annular poppet. 
     The present application further describes an annular dual-flow check valve for controlling the flow through concentric channels that have a common outlet, comprising: an outer body and an inner body that define the concentric channels, which include an outer channel and an inner channel formed therein; a spring activated annular poppet that resides in the outer channel and has a range of motion in the axial direction; and an opening through the inner body that connects the outer channel to the inner channel; wherein: the axial movement of the annular poppet is regulated by the extent to which the pressure of the flow upstream of the annular poppet in the outer channel depresses the spring by pushing on the annular poppet; the axial range of motion of the annular poppet includes at least two axial positions: a closed position where the annular poppet substantially covers the opening and a open position where at least a portion of the opening is not covered by the annular poppet; and the spring and annular poppet are configured such that: when the level of pressure of the flow upstream of the annular poppet is below a first predetermine pressure level, the annular poppet resides in the closed position; and when the level of pressure of the flow upstream of the annular poppet is above a second predetermine pressure level, the annular poppet resides in the open position. 
     These and other features of the present application will become apparent upon review of the following detailed description of the preferred embodiments when taken in conjunction with the drawings and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other objects and advantages of this invention will be more completely understood and appreciated by careful study of the following more detailed description of exemplary embodiments of the invention taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a cross-section of a annular dual-flow check valve in accordance with an exemplary embodiment of the present application; and 
         FIG. 2  is another cross-sectional view of the annular dual-flow check valve of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the figures,  FIG. 1  illustrates a section view of an annular dual-flow check valve  10  according to an exemplary embodiment of the present invention. As illustrated, the annular dual-flow check valve  10  may include an outer body  12  and an inner body  14  that define concentric flow channels, an outer channel  16  and an inner channel  18 . The annular dual-flow check valve  10  further may include an assembly end-cap or end-cap  20 , a spring  22 , and an annular check poppet or annular poppet  24 , which will be discussed in more detail below. 
     The outer body  12  generally forms a hollow chamber that is substantially cylindrical in shape and which forms the outer boundary of the outer channel  16 . The inner wall of the outer body  12  may have grooves  26  or steps  28  formed therein, which, as discussed in more detail below, may be used to secure or fix the axial position of other components within the outer body  12 , though, as one of ordinary skill in the art will appreciate, other conventional methods or mechanical connections may also be used. The upstream end of the outer body  12  may be formed with a connecting means, such as, for example, a threaded outer surface  30 , which may be used to connect the outer body  12  to another pipe. Other means of attachment also may be used. Note that, given the depiction of the annular dual-flow check valve  10  in  FIG. 1 , the flow through it, in operation, will move in a general left to right direction. The relative positioning of components may be described with an “upstream” or “downstream” designation. Accordingly, components on the left side may be referred to as being on the “upstream” side while components on the right side may be referred to as being on the “downstream” side. It will be appreciated that this description relates to the direction of flow through the annular dual-flow check valve  10 . In addition, the annular dual-flow check valve  10  may be used to channel flows of gases or liquids, or a combination of a flow of liquids and a flow of gas. 
     The inner body  14  generally forms a hollow chamber that is cylindrical in shape. The outer surface of the inner body  14  generally forms the inner boundary of the outer channel  16  and the inner surface of the inner body  14  generally forms the outer boundary of the inner channel  18 . The inner body  14  is sized and configured such that it may be inserted within the outer body  12 . (Note that the preferred embodiment of  FIG. 1  is described as comprising an assembly of separate parts. This is exemplary only. As one of ordinary skill in the art will appreciate, the outer body  12  could be constructed such that it is integral to the inner body  14  and/or to some of the other parts described.) Generally, moving from the upstream end to the downstream end, the inner body  14  may include an inlet  32 , a flange  34 , a mid-body  36 , and an outlet  38 , all of which have the inner channel  18  defined therethrough. (Note that the description of these several parts of the inner body  14  is done for the convenience of clear description and not intended to be limiting in any way.) The inlet  32  generally forms the inlet to the inner channel  18  that extends through the inner body  14 , and comprises a relatively thin sleeve or wall that defines a hollow cylindrical passageway. The inlet  32  may extend upstream a desired distance and, as shown, may terminate with a connecting means, such as, for example, an outer threaded surface  39 , which may be used to connect to another pipe or hollow passageway. 
     The flange  34  extends radially outward from the inner body  14  and makes a connection with the outer body  14  that substantially secures or fixes the axial position of the inner body  14  within the outer body  12 . For example, as shown, the flange  34  may have a diameter that is greater than the diameter at a narrow point or circumferential step  28  formed in the inner wall of the outer body  12 . Thereby, the step  28  may restrict the axial movement of the flange  34  (and thus the inner body  14 ) in one axial direction (as shown, the step restricts the movement of the flange  34  in the downstream direction). A groove  26  may be positioned just upstream of the upstream end of the flange  34 , and an insert  40  then may be used to engage the groove  26  and narrow the diameter of the outer channel  16 , similar in function to the step  28 . Thereby, as illustrated, the groove  26 /insert  40  assembly may restrict movement of the flange  34  (and thus the inner body  14 ) in the upstream direction. That is, the insert  40  may extend radially inward such that it prevents the flange  34  from moving upstream. As one of ordinary skill in the art will appreciate, other mechanical connections or configurations may be used to restrict the axial movement of the flange  34 /inner body  14 . Within the flange  34 , several flange channels  42  may be formed. The flange channels  42  may provide an axially oriented channel or opening through the flange  34  such that the flow through the outer channel  16  may pass through the flange  34 , i.e., the flange  34  does not block the flow through the outer channel  16 . The flange channels  42  may be sized and configured depending on desired performance. 
     The mid-body  36  of the inner body  14  generally may extend axially from the flange  34  in a downstream direction. The mid-body  36  may include a relatively thin sleeve or wall that defines a hollow cylindrical passageway. Within the mid-body  36 , multiple passageways or apertures may be formed through the sleeve or wall that defines the inner channel  18 . As shown in  FIG. 1 , these passageways or apertures may comprise slots  44  in certain preferred embodiments. In general, the slots  44  form openings between the outer channel  16  and the inner channel  18  such that the outer channel  16  is in fluid communication with the inner channel  18 . As illustrated in the embodiment of  FIG. 1 , the slots  44  may be axially oriented elongated openings. As stated, openings of other shapes also may be used, such as, for example, multiple circular apertures or holes. As explained in more detail below, the axial location of the slots  44  generally will coincide with the axial location of the annular poppet  24  and its range of motion. 
     The outlet  38  generally forms the outlet of the inner channel  18  that extends through the inner body  14 . The outlet  38  generally extends downstream a desired distance from the mid-body  36  and, as shown, may terminate after a relatively short distance with a connecting means, such as, for example, a threaded outer surface  46 . The threaded outer surface  46  of the outlet  38  may be used to connect the inner body  14  to a pipe or other fitting so that the inner channel  18  continues downstream. 
     The end-cap  20  may be formed at the downstream end of the outer body  12 . The end-cap  20  generally provides a stationary or fixed surface against which on end of the spring  22  may rest and, to fulfill this function, may be of several different designs, sizes and configurations. As shown, the end-cap  20  is circular in shape with a middle hole or passage through which the inner body may pass. The end-cap  20  may be held in place by a groove  26 /insert  40  assembly, though other mechanical connections may be used to secure the axial position of the end-cap  20 . 
     As described, one end of the spring  22  may rest against the end-cap  20 . The other end of the spring  2  may rest against the annular poppet  24 . The spring  22  may be a conventional spring or equivalent mechanical device that generally circumscribes the inner body  14 . As shown, the annular poppet  24  is a dough-nut shaped piece that is generally free to move axially against the spring  22  as the pressure of the flow through the outer channel  16  dictates. Further, the annular poppet  24  generally provides a solid piece that extends between the inner surface of the outer body  12  and the outer surface of the inner body  14 . The inner body  14  and the inner channel  18  may extend through the hollow opening in the center of the annular poppet  24 . The annular poppet  24  also may have several poppet grooves  48  cut into its inner and outer surfaces where guides  50  and/or o-rings  52  may be located. The guides  50  may be comprised of teflon or other suitable material and, as one of ordinary skill in the art will appreciate, may operate to assist the movement of the annular poppet  24 . The o-rings  52  be made of any suitable material, and, as one of ordinary skill in the art will appreciate, may function to seal the annular poppet  24  such that axial flow around the poppet  24  is substantially prevented. 
     The end-cap  20 , the spring  22 , and the annular poppet  24  may be configured within the outer body  12  and around the inner body  14  such that: 1) when the spring  22  is not compressed, the poppet  24  resides in an axial position that covers the slots  44  (thus preventing flow from the outer channel  16  to the inner channel  14  through the slots  44 ); and 2) when the spring is compressed, the poppet  24  resides downstream of the slots  44  such that one or more of the slots  44  are uncovered (thus allowing flow from the outer channel  16  to the inner channel  14  through the slots  44 ). A drain  54  may be located upstream of the end-cap  20 . The drain  54  may comprise an aperture or hole through the outer body  12  that provides an outlet for any fluids or gases that enter the outer channel  16  downstream of the poppet  24 . 
     The annular dual-flow check valve  10  assembly that is described above is configured such that it may be constructed and assembled in a cost-effective and efficient matter. For example, the end-cap  20  may be inserted into the outer body  12  through the upstream end and slid downstream until its axial movement is checked by a groove  26 /insert  40  assembly that is positioned near the downstream end of the outer body  14 . The spring  22  may then be inserted into the outer body  16  until it rests against the end-cap  20 . Then, the annular poppet  24  may be inserted into the outer body  16  until it rests against the spring  22 . The inner body  14  then may be inserted until the flange  34  rests against the step  28 . The flange  34  then may be bracketed between the step  28  and another groove  26 /insert  40  assembly positioned upstream of it, thereby securing the axial position of the inner body  14  within the outer body  12 . This generally completes the assembly of the annular dual-flow check valve  10  in accordance with an exemplary embodiment of the present invention. As one of ordinary skill there will appreciate, the specifics of the several mechanical connections may be varied without departing from the general design that allows such a convenient assembly. 
     In use, the annular dual-flow check valve  10  may operate as follows. As illustrated in  FIG. 1 , the pressure of the flow into the outer channel  18  may be insufficient to move the annular poppet  24  against the spring  22 , i.e., the flow may be insufficient to depress the spring  22 . In this case, the annular poppet  24  resides in a “closed position.” In the closed position, the annular poppet  24  may reside in substantially the same axial position as the slots  44 , thereby covering the slots  44 . Flow through the inner channel  18  may take place, but flow from the outer channel  16  to the inner channel  18  and from the inner channel  18  to the outer channel  16  is substantially blocked by the annular poppet  24 . As one of ordinary skill in the art will appreciate, such flow may be more completely blocked by the poppet  24  with the usage of the o-rings  52  that are positioned on either side of the slots  44 , i.e., the upstream side and the downstream side of the slot  44 . It will be appreciated that some flow may occur from the inner channel  18  through the slots  44  and provide pressure against the poppet  24 . However, the pressure of the flow through the slot  44  and against the poppet  24  is not oriented in a direction that engages or moves the poppet  24  against the spring  22 . Thus, the poppet  24  remains in a position to cover the slots  44  and prevents or substantially prevents flow from the inner channel  18  to the outer channel  16 . Again, the usage of the o-rings  52  may more completely block any such flow. 
     Alternatively, as illustrated in  FIG. 2 , a pressurized flow into the outer channel  16  may apply sufficient pressure against the annular poppet  24  such that the poppet  24  depresses the spring  22  and, thereby, moves axially in a downstream direction. When the annular poppet  24  has moved in the downstream direction such that the slots  44  are at least partially uncovered, the poppet  24  may be described as residing in an “open position.” In the open position, the gas or liquid from the outer channel  16  may flow into the inner channel  18  via the slots  44 . An upstream valve (not shown) in the inner channel  18  may stop the flow to the inlet  32  of the inner body  14 . In this case, the flow from the outer channel  16  through the slots  44  becomes substantially the entire flow through the inner body  14 . If the flow to the inlet  32  of the inner body  14  is maintained while the poppet  24  resides in the open position, the flow through the inner channel  18  and the outer channel  16  may be mixed. In certain cases, this type of operation may be advantageous. 
     As stated, the slots  44  may be configured differently for optimum operation. As illustrated, the slots  44  generally comprise axially oriented elongated openings. In a preferred embodiment, the slots  44  may be angled in a downstream direction from their opening in the outer surface of the inner body  14 . In a preferred embodiment, the axis of the slot  44  and the axis of the inner channel  18  may form an angle of between 30° and 60°. Among other advantages, this configuration may allow for enhanced and more efficient flow from the outer channel  16  to the inner channel  18 . Upstream of the slot  44 , as illustrated, the diameter of the outer surface of the inner body  14  may gradually narrow until the upstream end of the slots  44  is reached. Thus, the slots  44  may reside in a section that has a reduced diameter as the general diameter of the inner body  14 . This gradual narrowing that occurs upstream of the slots  44  may provide for more efficient flow into the slots  44  from the outer channel  16 . In addition, the gradual narrowing may allow the o-rings  52  to be incrementally or gradually loaded when the poppet  24  moves to the open position, which generally will prevent the o-rings  52  from being displaced by an immediate loading of the pressurized flow from the outer channel  16  that would occur otherwise. Downstream of the slots  44 , as illustrated, the diameter of the outer surface of the inner body  14  may gradually broaden until the general diameter of the inner body  14  is obtained. 
     From the above description of preferred embodiments of the invention, those skilled in the art will perceive improvements, changes and modifications. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims. Further, it should be apparent that the foregoing relates only to the described embodiments of the present application and that numerous changes and modifications may be made herein without departing from the spirit and scope of the application as defined by the following claims and the equivalents thereof.