The field to which the disclosure generally relates includes turbocharged internal combustion engines and more particularly, to flow control mechanisms.
In vehicles with turbocharged internal combustion engines, exhaust gases may be used to drive a turbine that is connected to, and drives a compressor. The compressor may be driven to compress combustion air into the engine's intake manifold. Internal combustion engines may also include an exhaust gas recirculation valve to admit exhaust gases into the intake manifold.
A number of variations may include product including a housing with an exhaust gas port, an inlet passage, and an outlet passage joined to the inlet passage by a valve chamber containing a plurality of vanes. The vanes may be arranged to: substantially close flow through the valve chamber; and induce swirl between the inlet passage and the outlet passage in both a first direction and a second direction. When the vanes substantially close flow through the valve chamber, flow from the exhaust gas port to the outlet port may be induced.
A number of other variations may include a mechanism for influencing flow that may have an inlet port, an outlet port, and a flow passage between the inlet port and the outlet port. A valve chamber may be positioned in the flow passage. An exhaust gas port may be configured to admit a flow of exhaust gas and may open into the flow passage between the valve chamber and the outlet port. The mechanism may include a set of vanes that may be arranged to: induce swirl between the inlet port and the outlet port in both a first direction and a second direction; and close off flow from the inlet port thereby inducing flow from the exhaust gas port to the outlet port.
A number of other variations may include a mechanism for effecting swirl and for throttling flow. The mechanism may include an inlet port, an outlet port, and a flow passage between the inlet port and the outlet port. A valve chamber may be in the flow passage. An exhaust gas port may be configured to admit a flow of exhaust gas into the flow passage and may open to the flow passage between the valve chamber and the outlet port. A set of vanes may be positioned in the valve chamber. Each vane in the set of vanes may include a leading edge, a trailing edge, and a maximum thickness that is located closer to the leading edge than to the trailing edge. The set of vanes may be configured to rotate to effect swirl and throttle flow. The set of vanes may also be configured to rotate effectively closing off flow from the inlet port to enhance flow from the exhaust gas port to the outlet port.
Other illustrative variations within the scope of the invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while disclosing variations within the scope of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
Select examples of variations within the scope of the invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
The following description of the variations is merely illustrative in nature and is in no way intended to limit the scope of the invention, its application, or uses.
Referring to
As can be seen in
Outlet housing section 38 may include a seal flange 42, an outlet flange 44 and an actuator flange 46. Seal flange 42 may be a generally cylindrical shaped section with an outwardly facing annular groove 48. The groove 48 may carry an annular seal 50 that engages the seal flange 32 of inlet housing section 26 to provide a seal for the chamber 40. Outlet flange 44 may be generally cylindrical in shape and may be adapted to receive a gas duct 52 to convey gas flow out of the swirl type LP-EGR throttle mechanism. Gas duct 52 may include an exhaust gas inlet port (not shown). Actuator flange 46 may be adapted to engage actuation ring 34 so that the inlet housing section 26 and actuation ring 34 define inlet passage 20. Outlet housing section 38 including actuator flange 46 defines an outlet passage 54. In addition, actuation ring 34 and outlet housing section 38, including actuator flange 46, define a chamber 56 that is shaped to closely fit with a set of vanes 24 (shown in an open position), to minimize gaps. The assembly may be carried in only two housing sections. Optionally the assembly may be attached directly to a compressor housing or integrated with a compressor housing.
When the vanes 24 are closed (as shown in
Through this mechanism, the vanes may be driven through a variety of positions one of which may be to close the flow path through the swirl type LP-EGR throttle mechanism. At this closed position the vane elements are perpendicular to the flow path at 90 degrees. Closing the flow path maximizes the draw of low pressure EGR gas downstream from the swirl type LP-EGR throttle mechanism. Another position may be to position the vanes such as to open the flow path through the swirl type LP-EGR throttle mechanism so that the vane elements are parallel to the flow path at 0 degrees. In addition, the driven end 120 may be rotated in one direction to move the vanes 95-99 to open the flow path providing a number of positions between 0 and 90 degrees of rotation that induces swirl in a first direction that may be in the same direction of rotation as a compressor wheel that may be downstream in the flow path. The driven end 120 may be rotated in a second direction to move the vanes 95-99 to open the flow path providing a number of positions between 0 and −90 degrees of rotation that induces swirl in a second direction that may be in the opposite direction of rotation as a compressor wheel that may be downstream in the flow path.
The vane design may be a one piece solution were the vane 95-99, shaft 101-105, lever arm 107-111, and joint 114-118, which may be achieved through injection molding or joined during assembly. In particular joining by 2k injection molding for plastics may be used by molding the vanes 95-99/shafts 101-105 into the joint 114-118 or bearing ring 80. To optimize mechanical and chemical properties different types of plastics may be paired. A material with higher grade and wear resistance may be used where needed and lower cost materials may be used for the balance of the component parts. Through 2k injection molding and use of a bearing ring or individual bearings, the vane shafts may be molded into the bearing openings. This may simplify the assembly process. Shrinkage of the shafts may be set to create the desired clearance between a shaft and its bore. Furthermore, wear and friction behavior may be optimized by using different materials. While molding the shaft into its bore, the vane elements and the levers or levers with joints may be molded to the shaft at the same time.
Referring to
The performance of the swirl type LP-EGR throttle mechanism can be measured by the quality of the swirl flow profile at the outlet, and the pressure losses generated. For small closing angles, the performance characteristics of the vane elements may preferably be such that the swirl angles match the vane angles with minimized pressure losses.
While changing the direction of flow between the leading edge of the vanes and the outlet during rotation of the vanes, a natural pressure gradient may be created between the vanes. This may result in sub-flow running through the gap between vane contour and inner housing contour, from the pressure side of one vane to the suction side of the other vane. Minimized gap flow may be achieved through an approximately spherical housing contour and a vane contour which follows the housing contour. This results in a gap that has a consistent width, independent from the angle orientation of the vanes. The vane contour may be created by rotating a radius around the center axis, leading to an equal gap width around the vane.
A valve housing 210 for a swirl type low pressure-EGR throttle mechanism 212 may be formed integrally with a compressor housing 214, or may be connected directly to a compressor housing 214 as shown in
Referring to
The following description of variants is only illustrative of components, elements, acts, products and methods considered to be within the scope of the invention and is not in any way intended to limit such scope by what is specifically disclosed or not expressly set forth. Components, elements, acts, products and methods may be combined and rearranged other than as expressly described herein and still are considered to be within the scope of the invention.
Variation 1 may include product including a housing with an exhaust gas port, an inlet passage, and an outlet passage joined to the inlet passage by a valve chamber containing a plurality of vanes. The vanes may be arranged to: substantially close flow through the valve chamber; and induce swirl between the inlet passage and the outlet passage in both a first direction and a second direction. When the vanes substantially close flow through the valve chamber, flow from the exhaust gas port to the outlet port may be induced.
Variation 2 may include a product according to variation 1 wherein at least part of the valve chamber may be defined by an actuation ring that may be rotatable to effect rotation of the vanes.
Variation 3 may include a product according to variation 1 or 2 wherein only one of the plurality of vanes may include a shaft that extends out of the housing and that may be configured to be rotatably driven.
Variation 4 may include a product according to variation 1 wherein the plurality of vanes includes a first vane and a set of other vanes. The first vane may include a shaft that extends out of the housing and that may be configured to be rotatably driven. An actuation ring may be configured to rotate in response to rotation of the first vane causing the set of other vanes to rotate in unison with the first vane
Variation 5 may include a product according to any of variations 1-4 wherein the plurality of vanes may be located in an upstream position relative to an exhaust gas recirculation port.
Variation 6 may include a product according to any of variations 1 through 5 wherein each of the plurality of vanes includes a vane element that has an airfoil like cross section.
Variation 7 may include a product according to any of variations 1 through 6 wherein the vanes substantially close flow between the inlet passage and the outlet passage without overlapping
Variation 8 may include a product according to any of variations 1 through 7 wherein each vane includes a shaft and a lever arm extending from the shaft
Variation 9 may include a product according to variation 8 wherein the actuation ring includes first and second radially extending arms coinciding with each lever arm.
Variation 10 may include a product according to variation 9 wherein each lever arm includes a ball joint positioned between the first and second radially extending arms.
Variation 11 may include a product according to any of variations 1-10 wherein the inlet passage may have a first effective diameter D1, the valve chamber may have a second effective diameter D2, and the outlet passage may have a third effective diameter D3. The ratio D2/D1 may preferably be between 1.01 and 1.04.
Variation 12 may include a product according to variation 11 wherein the ratio D2/D3 may preferably be between 1.25 and 1.5.
Variation 13 may include a mechanism for influencing flow. The mechanism may include an inlet port, an outlet port, and a flow passage between the inlet port and the outlet port. A valve chamber may be positioned in the flow passage. An exhaust gas port may be configured to admit a flow of exhaust gas into the flow passage and may open to the flow passage between the valve chamber and the outlet port. A set of vanes may be included wherein the set of vanes may be arranged to: induce swirl between the inlet port and the outlet port in both a first direction and a second direction; and close off flow from the inlet port thereby inducing flow from the exhaust gas port to the outlet port.
Variation 14 may include a mechanism according to variation 13 wherein the set of vanes may be positioned in a valve chamber. At least part of the valve chamber may be defined by an actuation ring that may be rotatable and configured to effect rotation of the vanes.
Variation 15 may include a mechanism according to variation 13 wherein each vane in the set of vanes may include a lever arm. An actuation ring may include a first and second radially extending arm corresponding to each lever arm. Each lever arm may extend between its corresponding first and second radially extending arms.
Variation 16 may include a mechanism according to variation 13 or 15 and may include a bearing that is annular shaped, is positioned around the set of vanes, and includes a set of openings. Each vane in the set of vanes may include an arm that extends through a corresponding opening in the bearing
Variation 17 may include a mechanism according to claim 16 wherein a slot may correspond to each vane in the set of vanes and may intersect each opening in the set of openings. Each vane in the set of vanes may include a lever arm extending through its corresponding slot.
Variation 18 may include a method according to variation 15 wherein the actuation ring may include a pair of arms that extend from the actuation ring and that may be configured to effect rotation of the vanes.
Variation 19 may include a method according to variation 18 wherein each vane in the set of vanes may include a lever arm that extends between one of the pairs of arms.
Variation 20 may include a mechanism for effecting swirl and for throttling flow. The mechanism may include an inlet port, an outlet port, and a flow passage between the inlet port and the outlet port. A valve chamber may be positioned in the flow passage. An exhaust gas port may be configured to admit a flow of exhaust gas into the flow passage. The exhaust gas port may open to the flow passage between the valve chamber and the outlet port. A set of vanes may be positioned in the valve chamber. Each vane in the set of vanes may include a leading edge, a trailing edge, and a maximum thickness that is located closer to the leading edge than to the trailing edge. The set of vanes may be configured to rotate to effect swirl and throttle flow. The set of vanes may also be configured to rotate closing off flow from the inlet port enhancing flow from the exhaust gas port to the outlet port.
Variation 21 may include a mechanism according to variation 13 wherein each vane may include a vane element, an extending shaft, a lever arm on the shaft, and a bearing joint on the shaft. The vane element, shaft, lever arm and bearing joint may be formed together by injection molding.
Variation 22 may include a mechanism according to variation 21 wherein the vane element, shaft, lever arm and bearing joint are formed as one piece comprised of at least two different materials.
Variation 23 may include a mechanism according to variation 21 wherein each shaft is formed in place in a bearing opening in the mechanism.
Variation 24 may include a mechanism according to variation 21 wherein each vane is molded on a respective shaft when the respective shaft is molded.
Variation 25 may include a mechanism according to variation 21 wherein each lever is molded on a respective shaft when the respective shaft is molded.
Variation 26 may include a mechanism according to variation 21 wherein a bearing is molded on each lever when the respective lever is molded.
Variation 27 may include a mechanism according to variation 13 wherein the valve chamber is spherical like in shape and includes an internal surface with a base sphere defined by the internal surface, the base sphere having a diameter, wherein the internal surface deviates from the diameter no more than plus or minus 15 percent.
Variation 28 may include a mechanism according to variation 13 wherein the mechanism is contained in a housing comprising no more than two separable sections.
Variation 29 may include a mechanism according to variation 28 wherein the exhaust gas port is defined by the two separable sections.
Variation 30 may include a mechanism according to variation 13 wherein the inlet port and at least part of the valve chamber may be formed in a first housing. The first housing may be connected directly to a second housing, and the second housing may be configured to house a compressor.
Variation 31 may include a mechanism according to variation 30 wherein the valve chamber is defined by the first housing and the second housing.
Variation 32 may include a mechanism according to variation 30 wherein the exhaust gas port is formed in the second housing.
Variation 33 may include a mechanism according to variation 30 with a bearing ring supporting the set of vanes and wherein the valve chamber may be defined by the first housing, the bearing ring, and the second housing
Variation 34 may include a mechanism according to variation 30 wherein the set of vanes is supported by the first housing.
The above description of select variations within the scope of the invention is merely illustrative in nature and, thus, variations or variants thereof are not to be regarded as a departure from the spirit and scope of the invention.