EP2422117A1

EP2422117A1 - Valve with offset bore

Info

Publication number: EP2422117A1
Application number: EP10767645A
Authority: EP
Inventors: Oswald Baasch; Jon A. Bigley; Steven Tedder
Original assignee: International Engine Intellectual Property Co LLC
Current assignee: International Engine Intellectual Property Co LLC
Priority date: 2009-04-20
Filing date: 2010-04-20
Publication date: 2012-02-29
Also published as: EP2422117A4; BRPI1016246A2; WO2010123910A1; JP2012524228A; CN102439337A

Abstract

A valve has a valve body having an inlet bore, an outlet bore in fluid communication with the inlet bore, and an offset formed between the inlet bore and the outlet bore. A valve plate is rotatably coupled with the valve body at a juncture of the inlet bore and the outlet bore. At least a portion of the valve plate forms a seal with the offset. A method of making a valve includes providing a valve body; providing a first bore in a first side of the valve body; and providing a second bore in a second side of the valve body that is in fluid communication with the first bore. The method further includes providing an offset between the first bore and the second bore and providing a valve plate at the juncture of the first bore and the second bore to selectively control fluid flow therebetween.

Description

VALVE WITH OFFSET BORE

BACKGROUND

[0001] Throttle plate type valves are meant to meter the fluids in a fluid supply system, such as an internal combustion engine. The throttle valve may meter fluids ranging from gaseous to liquid or a mixture of both. A typical throttle valve has a butterfly valve that has a throttle plate that meters low pressure or high pressure fluids.

SUMMARY

[0002] A valve is described. In at least one embodiment, a valve has a valve body having an inlet bore, an outlet bore in fluid communication with the inlet bore, and an offset formed between the inlet bore and the outlet bore. A valve plate is rotatably coupled with the valve body at a juncture of the inlet bore and the outlet bore. At least a portion of the valve plate forms a seal with the offset.

[0003] In another embodiment, a method of making a valve is provided. The method includes providing a valve body; providing a first bore in a first side of the valve body; and providing a second bore in a second side of the valve body that is in fluid communication with the first bore. The method further includes providing an offset between the first bore and the second bore and providing a valve plate at the juncture of the first bore and the second bore to selectively control fluid flow therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] In order to facilitate a fuller understanding of the exemplary embodiments, reference is now made to the appended drawings. These drawings should not be construed as limiting but are intended to be exemplary only.

[0005] FIG. 1 is an illustration of a prior art throttle valve with a circumferential seal. [0006] FIG. 2 is an illustration of a prior art throttle valve with a circumferential seal.

[0007] FIG. 3 is an illustration of a prior art throttle valve with an angular seal.

[0008] FIG. 4 is an illustration of a prior art throttle valve with an angular seal.

[0009] FIG. 5 is an illustration of a valve, in accordance with an exemplary embodiment described herein.

[0010] FIG. 6 is a sectional view of a valve body, in accordance with an exemplary embodiment described herein.

[0011] FIG. 7 is a perspective view of a valve, in accordance with an exemplary embodiment described herein.

[0012] FIG. 8 is an illustration of a valve, in accordance with an exemplary embodiment described herein.

[0013] FIG. 9 is a perspective view of a plate assembly, in accordance with an exemplary embodiment described herein.

[0014] FIG. 10 is a sectional view of a valve body, in accordance with an exemplary embodiment described herein.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0015] The following description is intended to convey a thorough understanding of the embodiments by providing a number of specific embodiments and details involving a valve such as a throttle valve. It is understood, however, that the invention is not limited to these specific embodiments and details, which are exemplary only. It is further understood that one possessing ordinary skill in the art, in light of known devices, systems, and methods, will appreciate the use of the invention for its intended purposes and benefits in any number of alternative embodiments. [0016] A few conventional throttle plate seal designs have been used to control valve leakage in a throttle valve when the valve is in a closed position. Referring to FIGS. 1 and 2, a first design is one having a circumferential seal between the throttle plate 100a and the bore 200a, typically with a minimal clearance between the throttle plate 100a and inner surface of the bore 200a. An elastomeric seal 300a may optionally be provided between the throttle plate 100a and the surface of the bore 200a. The circumferential seal, particularly a metal to metal seal, requires very tight manufacturing tolerances to reduce the binding potential due to thermal expansion and/or tolerance stack-up. Elastomeric seals may provide an improved seal, but some elastomers have fluid and thermal compatibility issues.

[0017] Referring to FIGS. 3 and 4, a second conventional throttle valve design is one having an angular contact seal between the throttle plate 100b and the inner surface of bore 200b. An elastomeric seal 300b may optionally provided between the throttle plate 100b and the bore 200b. The angular seal, particularly a metal to metal seal, reduces the angle of rotation of the plate causing a poor metering function.

[0018] In comparison to the conventional throttle valves, the valves of the various exemplary embodiments may provide improved sealing and leakage. Generally speaking, the valves of the various exemplary embodiments generally have a body, a central bore through the body providing a fluid inlet and a fluid outlet, and a plate assembly within the central bore to selectively meter fluid flow. The central bore has a first bore portion that is offset from a second bore portion, whereby the plate forms a face seal with offset portions of the first bore portion and/or second bore portion.

[0019] In addition to improved leakage performance, the exemplary valves may increase the dimensional tolerances, possibly making the valve less sensitive to sticktion caused by contamination and or condensates from exhaust gases. The valves of the exemplary embodiments also may be manufactured at a lower cost, and may require a less complex machining process for the plate. While the exemplary embodiments herein may be described in reference to a throttle valve, it will be understood that the valve may be used to control fluid flow in any suitable application.

[0020] Referring to FIGS. 5, 6, and 7, an exemplary throttle valve 500 has a body 510.

The body 510 may be made of any suitable material, such as, for example, aluminum, cast iron, stainless steel, plastic, etc. The body 510 may be a unitary body, or may be formed of a plurality of parts otherwise joined together.

[0021] In an exemplary embodiment, at least one central bore 600 is provided through the body 510, providing a fluid inlet 520 and fluid outlet 530 in the body 510. While the various embodiments may be described herein with reference to a single central bore 600, it will be appreciated that the body 510 may have multiple bores, either in series or parallel. For example, referring to FIG. 7, in an exemplary embodiment a body 510 may have two central bores 600, in parallel.

[0022] In the various exemplary embodiment, the central bore 600 has a first bore portion

610 and a second bore portion 620 that are in selective fluid communication with each other. The first bore portion 610 may be on the fluid inlet side or the fluid outlet side of the body 510, and has a first centerline 612 extending generally in a first direction, and has a first inner surface 614 that generally defines its inner periphery. The second bore portion 620 may be on the fluid inlet side or the fluid outlet side of the body 510 (opposite the first bore portion 610), and has a second centerline 622 extending generally in a second direction, and has a second inner surface 624 that generally defines its inner periphery. First bore portion 610 and second bore portion 620 meet at intersection 630, providing an orifice 632 therebetween.

[0023] In exemplary embodiments, the first bore portion 610 and the second bore portion

620 may be offset from each other. As used herein "offset" may refer to an offset of the first centerline 612 from second centerline 622, and/or an offset of at least a portion of first inner surface 614 from second inner surface 624. The offset of the first and second bore portions provides a face seal surface at the intersection 630 of the two offset bore portions. For example, referring to FIG. 6, an exemplary central bore 600 has a first bore portion 610 and a second bore portion 620 that are offset about their respective centerlines 612, 622, and their respective inner surfaces 614, 624, providing a first face seal surface 616 and a second face seal surface 626 at the intersection of the two offset bore portions.

[0024] In exemplary embodiments, the offset distance of the two bores can range from about 0.001 inch to the total diameter of the shaft. Limiting the offset distance to the diameter of the shaft may simplify machining and assembly of the throttle plate assembly 700 and body 510. Where the offset distance is larger than the diameter of the shaft, the throttle valve 500 may have a two-piece throttle plate 710 and/or two-piece body 510, and may involve complex bore machining and cause excessive fluid turbulence. In a preferred embodiment, the offset may be approximately 0.124 inch.

[0025] In an exemplary embodiments, the first bore portion 610 may be the same size as second bore portion 620. In other embodiments, first bore portion 610 and second bore portion 620 may have different sizes. For example, referring to FIG. 10, a body 510 may have a first bore portion 610 that has a first diameter, and a second bore portion 620 that has a second diameter that is smaller than that of the first bore portion 610. In exemplary embodiments in which the first bore portion 610 and second bore portion 620 have different sizes, the bores may be offset so that a portion of the inner surface 614 of the first bore portion 610 is aligned with a portion of the inner surface 624 of the second bore portion 620, and the opposite portion of the respective inner surfaces 614, 624 are offset, providing a first face seal surface 616. [0026] In various exemplary embodiments, the first bore portion 610 and second bore portion 620 may have any suitable cross-sectional shape. For example, the first bore portion 610 and/or second bore portion 620 may have a cross-section that is circular, oval, polygonal, heart, kidney, egg shape or any shape suitable for providing a predetermined fluid flow through the central bore 600.

[0027] In exemplary embodiments, throttle plate assembly 700 is rotatably coupled with the body 510 so that the throttle plate 710 is located at about the intersection 630 between first bore portion 610 and second bore portion 620. Referring to FIG. 9, an exemplary throttle plate assembly 700 may have a throttle plate 710 and a shaft 720. The shaft 720 may be integral with the throttle plate 710, or the two parts may be separately formed and otherwise joined together. For example, the shaft 720 may have a slot (not shown) through which throttle plate 710 may be inserted and fastened to the shaft 720. In an exemplary embodiment, the shaft 720 may be inserted into the body 510 so that it extends in a direction that is generally perpendicular to one or both of the first bore centerline 612 and second bore centerline 622. For example, body 510 may have a shaft bore 540 extending therethrough that is configured to receive the shaft 720 of the throttle plate assembly 700. The shaft bore 540 may extend through the outer surface of the body 510, so that it is accessible from the exterior of the body 510.

[0028] In exemplary embodiments, throttle plate 710 may have any suitable shape that enables it to rotate within the central bore 600, and provide a seal with portions of the central bore 600, as described herein. The throttle plate assembly 700, or any portion thereof, may be made of any suitable material, such as, for example, aluminum, cast iron, stainless steel, plastic, etc. The throttle plate 710 may have various other contours or devices, as necessary or desired, to provide structural or fluid flow characteristics. For example, the throttle plate 710 may have apertures to provide a calibrated leak when the throttle plate 710 is in a closed position. [0029] In various embodiments, the shaft 720 is seated in the body 510 , so that the throttle plate 710 may rotate about the axis of the shaft 720 between an open position and a closed position (substantially no fluid flow). In the closed position, the throttle plate 710 forms a face seal with the first face seal portion 616 and second face seal portion 626. For example, referring to FIG. 5, throttle plate 710 may have a first cheek 712 and a second cheek 714 that contact first face seal portion 616 and second face seal portion 626, respectively, when the throttle plate is in the closed position. As the throttle plate 710 rotates toward its open position, first cheek 712 pivots toward the centerline of the first bore portion 610, and the second cheek pivots toward the centerline of the second bore portion 620.

[0030] In some embodiments, the throttle plate 710 may form a face seal on one side, and a circumferential seal on the other side, such as where first bore 610 and second bore 610 have at least a portion of their inner surfaces aligned (e.g., the embodiment of FIG. 10). [0031] In various embodiments, the shaft 720 of the throttle plate assembly 700 may be disposed at about the centerline of the throttle plate 710. In other embodiments, the shaft 720 may be offset from the centerline of the throttle plate 710. In various embodiments, the shaft 720 may be coupled with the body 510 so that it is disposed at about the centerline of the orifice 632 between the two bores. It is believed that when the shaft 720 is centered with respect to the orifice 632, the pressure is generally balanced about the shaft 720. In other embodiments, the shaft 720 may be offset with respect to the orifice 632. It is believed that an off-center shaft 720 may generate off-center forces that may selectively bias the throttle plate toward an open or closed position.

[0032] In various embodiments, the throttle plate 710 may have a flat shape, or it may have a concave or convex shape. For example, the first cheek 712 and second cheek 714 may form a U-shape or a V-shape about the shaft 720. In exemplary embodiments, the throttle plate 710 may have a symmetrical shape, or it may have an asymmetrical shape. In exemplary embodiments, the throttle plate 710 may have a circular, oval, polygonal, heart, kidney, egg shape or any shape suitable for providing a seal with the first bore portion 610 and/or second bore portion 620. In certain exemplary embodiments, the throttle plate 710 may have a rhomboidal shape. It is believed that a throttle plate 710 having a rhomboidal shape may improve the robustness of the throttle plate 710, and also may improve the fluid flow around the shaft.

[0033] In exemplary embodiments, actuation of the valve 500 may be accomplished by any suitable means. For example, an exemplary valve may be actuated manually, pneumatically, hydraulically or electrically and directly coupled, magnetically coupled or driven via levers and pushrods, etc. Exemplary valves and actuators are described in U.S. Patent Nos. 7,591,245, and 7,658,177 (both entitled "Air Valve and Method of Use"), the disclosures of which are incorporated herein by reference in their entirety.

[0034] The valve 500 of the exemplary embodiments, having an offset bore configuration may provide improved leakage over the conventional circumferential valve and the angular contact valve. In many embodiments, the fluid leakage about the shaft 720 is so low that no additional sealing about the shaft 720 is necessary. In some embodiments, additional shaft sealing means such as labyrinth seals, spring energized axial seals, radial sealing rings (piston rings) may be used to further reduce the lateral leakage, such as, for example, in high temperature applications. In some embodiments, particularly for applications below 300⁰C, spring or elastomeric energized Teflon® based shaft seals can be used to reduce the lateral leakage by the shaft.

[0035] In various exemplary embodiments one or more of the bore 600 and the throttle plate assembly 700 may be machined to optimize the dynamic fluid flow through the valve 500 as the throttle plate 710 rotates. For example, referring to FIG. 8, the first bore 610 and/or the second bore 620 may have at least one contoured surface adjacent the edge of the throttle plate. As the throttle plate 720 initially rotates from its closed position toward its open position, such as for about the initial 20 degrees of rotation, the gap between the edge of the throttle plate 720 and the inner surface 614 or 624 of the bore remains substantially constant or changes only slightly, limiting the flow around the plate. In an exemplary embodiment, the contour may be configured to have a circular profile, which may provide no flow or constant flow for a certain range of rotation of the throttle plate 710. In another exemplary embodiment, the contour may be configured to have a parabolic profile, to provide accurate flow modulation over a certain range of rotation of the throttle plate 710.

[0036] In exemplary embodiments, a method of manufacturing a throttle valve 500 having offset bores may be provided. According to the method, the throttle valve 500 may be manufactured by providing a body 510, providing a first bore portion 610 in a first side 512 of the body 510, and providing a second bore portion 620 in a second side 514 of the body 510. The second bore 620 is configured so that it terminates adjacent an end of the first bore 610, so that it is in fluid communication with the first bore 610. The first bore 610 and the second bore 620 are offset from each other.

[0037] In an exemplary embodiment, body 510 may be provided by any suitable means.

For example, body 510 may include one or more cast parts and the central bore 600, and/or other parts may be "cast in" to the body 510, such as by using a lost foam casting process, a lost core investment casting process, a salt core casting process, or the like. In other embodiments, body 510 may be molded, and the offset bore portions 610 and 620 and other parts may be molded into the body, such as by injection molding or the like. In other exemplary embodiments, the offset bore portions 610 and 620 may be formed in the body 510 using any commonly known manufacturing method. For example, the bores may be formed by machining and removing billets, etc. One having ordinary skill in the art would understand the various methods of forming the offset bores in the valve body 510. In some embodiments, multiple bores may be provided in the body 510, either in parallel or series.

[0038] According to the exemplary methods, the throttle plate assembly 700 may be rotatably coupled with the body 510 using any suitable means. For example, the throttle plate assembly 700, or any part thereof, may be inserted into the valve through one of the bores 610 or 620. Shaft 720 may be inserted into one or more shaft bores 540 in the body 510, either from the bore side or from the exterior of the body 500, providing an axis of rotation for the throttle plate 710. In exemplary embodiments, the valve 500 may be coupled with any suitable actuator means capable of rotating the throttle plate assembly 700 between an open and closed position. [0039] In the preceding specification, various embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments implemented, without departing from the broader scope of the exemplary embodiments as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense.

Claims

What is claimed is:

1. A valve comprising: a valve body having an inlet bore, an outlet bore in fluid communication with the inlet bore, and an offset formed between the inlet bore and the outlet bore; and a valve plate rotatably coupled with the valve body at a juncture of the inlet bore and the outlet bore; wherein at least a portion of the valve plate forms a seal with the offset.

2. The valve of claim 1, wherein the inlet bore and the outlet bore have approximately the same diameter.

3. The valve of claim 1, wherein the inlet bore and the outlet bore have different diameters.

4. The valve of claim 1, wherein at least one of the inlet bore and the outlet bore have a cylindrical cross-section.

5. The valve of claim 1, further comprising a shaft coupled with the valve plate, providing an axis of rotation.

6. The valve of claim 5, wherein the shaft is integral with the valve plate.

7. The valve of claim 5, wherein the shaft is disposed at about the center of the valve plate.

8. The valve of claim 5, wherein the shaft is offset from the center of the valve plate.

9. The valve of claim 1, wherein the valve plate forms a face seal with the offset.

10. The valve of claim 1, wherein the valve plate forms a circumferential seal with a surface of one of the inlet bore and the outlet bore.

11. The valve of claim 1 , wherein the valve plate rotates between an open position and a closed position.

12. The valve of claim 5, wherein the offset is from about 0.001 inches to about a diameter of the shaft.

13. The valve of claim 1, wherein the inlet bore and the outlet bore have the same central axis.

14. The valve of claim 1, wherein a portion of the inlet bore or the outlet bore has a contoured surface adjacent an edge of the valve plate, whereby as the valve plate rotates from a closed position toward an open position, a substantially constant distance is maintained between a distal edge of the valve plate and the contoured surface.

15. A method of making a valve comprising: providing a valve body; providing a first bore in a first side of the valve body; providing a second bore in a second side of the valve body and in selective fluid communication with the first bore; providing an offset between the first bore and the second bore; and providing a valve plate at the juncture of the first bore and the second bore to selectively control fluid flow therebetween; wherein at least a portion of the valve plate forms a seal with the offset.

16. The method of claim 15, further comprising: providing a second offset between the first bore and the second bore.

17. The method of claim 15, wherein the inlet bore and the outlet bore have approximately the same diameter.

18. The method of claim 15, wherein the inlet bore and the outlet bore have different diameters.

19. The method of claim 15, wherein at least one of the inlet bore and the outlet bore have a cylindrical cross-section.

20. The method of claim 15, wherein the first bore and the second bore have the same central axis.

21. The method of claim 15, further comprising: providing a shaft coupled with the valve plate forming an axis of rotation.

22. The method of claim 21, wherein the shaft is integral with the valve plate.

23. The method of claim 21, wherein the shaft is disposed at about the center of the valve plate.

24. The method of claim 21, wherein the shaft is offset from the center of the valve plate.

25. The method of claim 15, wherein the valve plate forms a face seal with the offset.

26. The method of claim 15, wherein the valve plate forms a circumferential seal with a surface of one of the inlet for and the outlet bore.

27. The method of claim 15, wherein the valve plate rotates between an open position and a closed position.

28. The method of claim 21, wherein the offset is from about 0.001 inches to about a diameter of the shaft.

29. The method of claim 15, wherein a portion of the first bore or the second bore has a contoured surface adjacent an edge of the valve plate, whereby as the valve plate rotates from a closed position toward an open position, a substantially constant distance is maintained between a distal edge of the valve plate and the contoured surface.

30. A method of using a valve, comprising: providing a valve body; providing a first bore in a first side of the valve body; providing a second bore in a second side of the valve body and in selective fluid communication with the first bore; providing an offset between the first bore and the second bore; providing a valve plate at a juncture of the first bore and the second bore, wherein at least a portion of the valve plate forms a seal with the offset; and selectively controlling fluid flow between the first bore and the second bore by rotating the valve plate.