Control valve

A control valve includes a first conduit having a first inlet and a first outlet and defining a first passage; a second conduit having a second inlet and a second outlet and defining a second passage, the second conduit extending into the first passage such that the second inlet is located within the first passage; and a valve plate disposed pivotably within the first passage, the valve plate defining a valve plate surface. Pivoting of the valve plate within the first passage varies flow from the first inlet to the first outlet and the valve plate is pivotal between a first position and a second position such that in the first position the valve plate substantially prevents fluid communication between the first passage and the second passage and such that in the second position the valve plate permits fluid communication between the first passage and the second passage.

TECHNICAL FIELD OF INVENTION

The present invention relates to a control valve; more particularly to a control valve which controls flow through a first fluid passage and a second fluid passage; and even more particularly to such a control valve where the second fluid passage extends into the first fluid passage and a valve plate is pivotal within the first fluid passage to control flow through the first fluid passage and the second fluid passage.

BACKGROUND OF INVENTION

A fluid stream from a fluid source may need to be divided and sent to first and second fluid destinations in variable proportions. In one example, a stream of air to be supplied to combustion chambers of an internal combustion engine may be divided in order to achieve a desired temperature of the air being supplied to the combustion chambers. More specifically, a first portion of the stream of air may be passed through a heating or cooling device prior to entering the combustion chambers while a second portion of the stream of air may be passed directly to the combustion chambers. A control valve is used to vary the proportions of the first and the second portions of the stream of air. The combination of the first and second portions of the stream of air, downstream of the heating or cooling device, results in air of a desired temperature that is conducive of desired combustion by the internal combustion engine. In another example, exhaust gases produced by the combustion process of an internal combustion engine may be recirculated back to the combustion chambers in order to achieve desired operating characteristics of the internal combustion engine. The exhaust gases as produced by the internal combustion engine may be too high in temperature to be satisfactory to be communicated directly to the combustion chambers. Consequently, a heat exchanger may be provided to cool the exhaust gases prior to being communicated to the combustion chambers. The exhaust gases may be divided into a first portion which passes through the heat exchanger and a second portion which bypasses the heat exchanger. A control valve is used to vary the proportions of the first and the second portions of the exhaust gases. After passing through the heat exchanger, the first portion is combined with the second portion, the combination of which results in a temperature of the exhaust gases that is conducive of desired combustion by the internal combustion engine. Other examples exist of dividing a flow stream with a control valve that varies the proportions between the first and second portions of the flow stream. In many cases, there may be a high dynamic flow range, i.e. there is a significant difference in the minimum and maximum flow of the flow stream that needs to be divided; and consequently, it may be difficult for a control valve to accommodate the dynamic flow range without inducing parasitic losses. United States Patent Application Publication No. US 2009/0007978 A1 to Alston et al. and U.S. Pat. No. 6,484,703 to Bailey illustrate examples of known valves for dividing a flow stream; however, the valves can be large and difficult to package in addition to experiencing the shortcomings already mentioned.

What is needed is a control valve which minimizes or eliminates one or more of the shortcomings as set forth above.

SUMMARY OF THE INVENTION

Briefly described, a control valve is provided which includes a first fluid conduit having a first fluid conduit inlet and a first fluid conduit outlet, the first fluid conduit defining a first fluid passage from the first fluid conduit inlet to the first fluid conduit outlet; a second fluid conduit having a second fluid conduit inlet and a second fluid conduit outlet, the second fluid conduit extending into the first fluid passage such that the second fluid conduit inlet is located within the first fluid passage, and the second fluid conduit defining a second fluid passage extending from the second fluid conduit inlet to the second fluid conduit outlet; and a valve plate disposed pivotably within the first fluid passage between the first fluid conduit inlet and the first fluid conduit outlet, the valve plate defining a valve plate surface. Pivoting of the valve plate within the first fluid passage varies flow from the first fluid conduit inlet to the first fluid conduit outlet and the valve plate is pivotal between a first position and a second position such that in the first position the valve plate surface covers the second fluid conduit inlet, thereby substantially preventing fluid communication between the first fluid passage and the second fluid passage and such that in the second position the valve plate surface does not cover the second fluid conduit inlet, thereby permitting fluid communication between the first fluid passage and the second fluid passage. The control valve described herein accommodates a high dynamic range of flow and is easily adapted to achieve flow characteristics through the first fluid passage and the second fluid passage by modifying the geometry of the second fluid conduit inlet and the sizes and shapes of the first fluid passage and the second fluid passage.

DETAILED DESCRIPTION OF INVENTION

In accordance with a preferred embodiment of the present invention and referring toFIGS. 1-3, a control valve10is shown which controls flow of a fluid between a fluid source12and a first fluid destination14and also between fluid source12and a second fluid destination16. Control valve10generally includes a first fluid conduit18, a second fluid conduit20, and a valve plate22which interacts with first fluid conduit18and second fluid conduit20in order to control flow of the fluid between fluid source12and first fluid destination14and also between fluid source12and second fluid destination16. The elements of control valve10will be described in greater detail in the paragraphs that follow.

First fluid conduit18includes a first fluid conduit inlet24which introduces fluid into control valve10and a first fluid conduit outlet26which discharges fluid from control valve10. First fluid conduit inlet24is configured to receive fluid from fluid source12while first fluid conduit outlet26is configured to discharge fluid to first fluid destination14. First fluid conduit18defines a first fluid passage28extending therethrough along a first fluid passage axis30from first fluid conduit inlet24to first fluid conduit outlet26. As illustrated herein, first fluid passage28may be circular in radial cross-sectional shape, however, it should now be understood that first fluid passage28may be any radial cross-sectional shape and remain within the spirit of the invention.

Second fluid conduit20extends into first fluid passage28and includes a second fluid conduit inlet32such that second fluid conduit inlet32is located within first fluid passage28and such that second fluid conduit inlet32introduces fluid into second fluid conduit20. Second fluid conduit20also includes a second fluid conduit outlet34which discharges fluid from second fluid conduit20. Second fluid conduit inlet32is configured to receive fluid from first fluid passage28while second fluid conduit outlet34is configured to discharge fluid to second fluid destination16. Second fluid conduit20defines a second fluid passage36extending therethrough along a second fluid passage axis38from second fluid conduit inlet32to second fluid conduit outlet34. It should be noted that second fluid passage36is located at least partially within first fluid passage28by virtue of second fluid conduit20extending into first fluid passage28. As illustrated herein, second fluid passage36may be circular in radial cross-sectional shape, however, it should now be understood that second fluid passage36may be any radial cross-sectional shape and remain within the spirit of the invention. Also as illustrated herein, second fluid conduit inlet32is oblique to second fluid passage axis38and second fluid passage axis38is oblique to first fluid passage axis30, however, it should be noted that it is not essential for second fluid passage axis38to be oblique to first fluid passage axis30and it is also not essential for second fluid conduit inlet32to be oblique to second fluid passage axis38.

Valve plate22is what is commonly referred to as a butterfly valve and is pivotably disposed within first fluid passage28between first fluid conduit inlet24and first fluid conduit outlet26. Valve plate22includes a valve shaft40which extends along a valve shaft axis42which may be substantially perpendicular to first fluid passage axis30. Valve shaft axis42may preferably pass through first fluid passage axis30which results in the force of the fluid within first fluid passage28acting on valve plate22to be balanced, thereby minimizing the tendency for the fluid to apply a net torque to valve plate22that would tend to rotate valve plate22about valve shaft axis42. Valve shaft40pivots together with valve plate22such that opposing ends of valve shaft40extend through the wall of first fluid conduit18. In this way, valve shaft40and valve plate22are supported by first fluid conduit18at opposing ends of valve shaft40. Valve shaft40, and consequently valve plate22, is pivoted about valve shaft axis42by an actuator44which is connected to valve shaft40through linkage46. Alternatively, actuator44may directly rotate valve shaft40, thereby eliminating the need for linkage46.

Valve plate22has a first valve plate surface22aand an opposing second valve plate surface22bsuch that first valve plate surface22amay be substantially parallel to second valve plate surface22b. Valve plate22defines a valve plate outer perimeter48which closely matches a first fluid conduit inner perimeter50of first fluid conduit18when valve plate22is in a closed position which substantially prevents fluid communication between first fluid conduit inlet24and first fluid conduit outlet26as shown inFIG. 2. It should be understood that some leakage past valve plate22within acceptable limits may be permitted while remaining within the scope of substantially preventing fluid communication between first fluid conduit inlet24and first fluid conduit outlet26as used herein. As shown inFIG. 2, valve plate22may be oblique to first fluid passage axis30when valve plate22is positioned to prevent fluid communication between first fluid conduit inlet24and first fluid conduit outlet26, consequently, valve plate outer perimeter48may be elliptical in shape in order to match first fluid conduit inner perimeter50. Also as shown inFIG. 2, first fluid conduit18acts as a first stop which limits the extent to which valve plate22is permitted to pivot in a first direction, which as shown inFIG. 2may be counterclockwise. Alternatively, valve plate22may be substantially perpendicular to first fluid passage axis30when valve plate22is positioned to prevent fluid communication between first fluid conduit inlet24and first fluid conduit outlet26, consequently, valve plate outer perimeter48would be circular in shape if first fluid conduit inner perimeter50is circular in shape. However, it should now be understood that the shape of valve plate outer perimeter48is dependent upon the shape of first fluid conduit inner perimeter50and the angle at which valve plate22is relative to first fluid passage axis30when valve plate22is positioned to prevent fluid communication between first fluid conduit inlet24and first fluid conduit outlet26. As valve plate22is rotated clockwise from the position shown inFIG. 2, the area of first fluid passage28that is available to flow fluid increases until valve plate22is in a full open position as shown inFIG. 3where valve plate22is coincident with first fluid passage axis30. In this way, pivoting of valve plate22varies flow from first fluid conduit inlet24to first fluid conduit outlet26.

In addition to valve plate22varying flow from first fluid conduit inlet24to first fluid conduit outlet26, valve plate22also varies flow from second fluid conduit inlet32to second fluid conduit outlet34. As can be seen inFIG. 2, valve plate22does not restrict flow from first fluid passage28to second fluid passage36when valve plate22is positioned to prevent flow from first fluid conduit inlet24to first fluid conduit outlet26. However, as valve plate22is rotated clockwise, valve plate22moves toward second fluid conduit inlet32, thereby allowing a portion of flow from fluid source12to pass to first fluid destination14and also restricting flow from first fluid passage28to second fluid passage36at some positions of valve plate22. When valve plate22has rotated sufficiently far clockwise, first valve plate surface22acomes into contact with second fluid conduit inlet32, thereby covering second fluid conduit inlet32and substantially preventing fluid communication between first fluid passage28and second fluid passage36. It should be understood that some leakage past valve plate22within acceptable limits may be permitted while remaining within the scope of substantially preventing fluid communication between first fluid passage28and second fluid passage36as used herein. In this way, second fluid conduit20acts as a second stop which limits the extent to which valve plate22is permitted to pivot in a second direction, which as shown inFIG. 3may be clockwise, and is opposite in direction from the direction in which first fluid conduit18acts as a stop. As can be seen best inFIG. 3, second fluid conduit inlet32is substantially parallel to first fluid passage axis30and is positioned within first fluid passage28to allow first valve plate surface22ato seal against second fluid conduit inlet32when valve plate22is positioned to provide minimum restriction to flow through first fluid passage28.

In an alternative embodiment as shown inFIGS. 4-6, a control valve110is shown which controls flow of a fluid between a fluid source112and a first fluid destination114and also between fluid source112and a second fluid destination116. Control valve110generally includes a first fluid conduit118, a second fluid conduit120, and a valve plate122which interacts with first fluid conduit118and second fluid conduit120in order to control flow of the fluid between fluid source112and first fluid destination114and also between fluid source112and second fluid destination116. The elements of control valve110will be described in greater detail in the paragraphs that follow.

First fluid conduit118includes a first fluid conduit inlet124which introduces fluid into control valve110and a first fluid conduit outlet126which discharges fluid from control valve110. First fluid conduit inlet124is configured to receive fluid from fluid source112while first fluid conduit outlet126is configured to discharge fluid to first fluid destination114. First fluid conduit118defines a first fluid passage128extending therethrough along a first fluid passage axis130from first fluid conduit inlet124to first fluid conduit outlet126. As illustrated herein, first fluid passage128may be circular in radial cross-sectional shape, however, it should now be understood that first fluid passage128may be any radial cross-sectional shape and remain within the spirit of the invention.

Second fluid conduit120extends into first fluid passage128and includes a second fluid conduit inlet132such that second fluid conduit inlet132is located within first fluid passage128and such that second fluid conduit inlet132introduces fluid into second fluid conduit120. Second fluid conduit120also includes a second fluid conduit outlet134which discharges fluid from second fluid conduit120. Second fluid conduit inlet132is configured to receive fluid from first fluid passage128while second fluid conduit outlet134is configured to discharge fluid to second fluid destination116. Second fluid conduit120defines a second fluid passage136extending therethrough along a second fluid passage axis138from second fluid conduit inlet132to second fluid conduit outlet134. It should be noted that second fluid passage136is located at least partially within first fluid passage128by virtue of second fluid conduit120extending into first fluid passage128. As illustrated herein, second fluid passage136may be circular in radial cross-sectional shape, however, it should now be understood that second fluid passage136may be any radial cross-sectional shape and remain within the spirit of the invention. Also as illustrated herein second fluid conduit inlet132is oblique to second fluid passage axis138.

Valve plate122is what is commonly referred to as a butterfly valve and is pivotably disposed within first fluid passage128. Valve plate122includes a valve shaft140which extends along a valve shaft axis142which may be substantially perpendicular to first fluid passage axis130. Valve shaft axis142may preferably pass through first fluid passage axis130which results in the force of the fluid within first fluid passage128acting on valve plate122to be balanced, thereby minimizing the tendency for the fluid to apply a net torque to valve plate122that would tend to rotate valve plate122about valve shaft axis142. Valve shaft140pivots together with valve plate122such that opposing ends of first fluid conduit118extend through the wall of first fluid conduit118. In this way, valve shaft140is supported by first fluid conduit118at opposing ends of valve shaft140. Valve shaft140, and consequently valve plate122, is pivoted about valve shaft axis142by an actuator (not show) as describe previously relative to control valve10.

Valve plate122has a first valve plate surface122aand an opposing second valve plate surface122bsuch that first valve plate surface122amay be substantially parallel to second valve plate surface122b. Valve plate122defines a valve plate outer perimeter148which closely matches a first fluid conduit inner perimeter150of first fluid conduit118when valve plate122is in a closed position which substantially prevents fluid communication between first fluid conduit inlet124and first fluid conduit outlet126as shown inFIGS. 4 and 6. It should be understood that some leakage past valve plate122within acceptable limits may be permitted while remaining within the scope of substantially preventing fluid communication between first fluid conduit inlet124and first fluid conduit outlet126as used herein. As shown inFIGS. 4 and 6, valve plate122may be oblique to first fluid passage axis130when valve plate122is positioned to prevent fluid communication between first fluid conduit inlet124and first fluid conduit outlet126, consequently, valve plate outer perimeter148may be elliptical in shape in order to match first fluid conduit inner perimeter150. However, it should now be understood that the shape of valve plate outer perimeter148is dependent upon the shape of first fluid conduit inner perimeter150and the angle at which valve plate122is relative to first fluid passage axis130when valve plate122is positioned to prevent fluid communication between first fluid conduit inlet124and first fluid conduit outlet126. Also as shown inFIGS. 4 and 6, first fluid conduit118acts as a first stop which limits the extent to which valve plate122is permitted to pivot in a first direction, which as shown inFIG. 4may be counterclockwise. As valve plate122is rotated clockwise from the position shown inFIG. 4, the area of first fluid passage128that is available to flow fluid increases until valve plate122is in a full open position as shown inFIG. 5where valve plate122is coincident with first fluid passage axis130. In this way, pivoting of valve plate122varies flow from first fluid conduit inlet124to first fluid conduit outlet126.

In addition to valve plate122varying flow from first fluid conduit inlet124to first fluid conduit outlet126, valve plate122also varies flow from second fluid conduit inlet132to second fluid conduit outlet134. As can be seen inFIG. 4, valve plate122does not restrict flow from first fluid passage128to second fluid passage136when valve plate122is positioned to prevent flow from first fluid conduit inlet124to first fluid conduit outlet126. However, as valve plate122is rotated clockwise, valve plate122moves toward second fluid conduit inlet132, thereby allowing a portion of flow from fluid source112to pass to first fluid destination114and also restricting flow from first fluid passage128to second fluid passage136at some positions of valve plate122. When valve plate122has rotated sufficiently far clockwise, first valve plate surface122acomes into contact with second fluid conduit inlet132, thereby covering second fluid conduit inlet132and substantially preventing fluid communication between first fluid passage128and second fluid passage136. When valve plate122has rotated sufficiently far to prevent fluid communication between first fluid passage128and second fluid passage136, valve plate122has also rotated sufficiently far to allow valve plate outer perimeter148to again engage first fluid conduit inner perimeter150, thereby substantially preventing fluid communication between first fluid conduit inlet124and first fluid conduit outlet126as shown inFIG. 6. In this way, first fluid conduit118and second fluid conduit120act together as a second stop which limits the extent to which valve plate122is permitted to pivot in a second direction, which as shown inFIG. 6may be clockwise, and is opposite in direction from the direction in which first fluid conduit118acts alone as a stop. As described herein, control valve110allows for first fluid passage128and second fluid passage136to be simultaneously blocked by valve plate122, unlike control valve10which allows only one of first fluid passage28and second fluid passage36to be blocked at a time.

Control valve10and control valve110accommodate a high dynamic range of flow from fluid source12and fluid source112respectively. Furthermore, second fluid conduit inlet32and second fluid conduit inlet132can be easily modified by changing the position or angle thereof within first fluid passage28and first fluid passage128respectively in order to achieve desired flow characteristics of control valve10and control valve110. Other aspects of control valve10and control valve110can also be easily modified, for example, the size and shape of first fluid passage28, first fluid passage128, second fluid passage36, and second fluid passage136in order to achieve desired flow characteristics of control valve10and control valve110.

While this invention has been described in terms of preferred embodiments thereof, it is not intended to be so limited, but rather only to the extent set forth in the claims that follow.