Patent Application
20130195607
The technical field generally relates to inlet designs for pump assemblies.
Pump assemblies having impellers are sometimes designed with an inlet passage that feeds fluid to the impeller. One example of such a pump assembly is a secondary air pump assembly that supplies secondary or intake air to an automotive exhaust system during warm-up of an automotive internal combustion engine, or at other times.
One embodiment includes an air pump assembly that may include an impeller, a housing, and a diverter. The impeller may have an axial face and a circumferential periphery. The housing may surround the impeller. The housing may form a part or more of a primary passage for air flow during use of the air pump assembly. The primary passage may be open to the impeller at the axial face of the impeller. The housing may have an inlet passage that may communicate with the primary passage. The inlet passage may have a longitudinal axis that may be arranged generally non-orthogonally with respect to an axis of rotation of the impeller. The diverter may be located partially or more within the inlet passage. The diverter may have a surface that may confront the axial face of the impeller, may confront the circumferential periphery of the impeller, or may confront both the axial face and the circumferential periphery. When the air pump assembly is in use, the diverter may inhibit generation of turbulent flow between incoming air flow and the impeller where the surface confronts the impeller.
One embodiment includes a method. The method may include providing an air pump assembly that may comprise an impeller and a housing. The impeller may have numerous vanes and an axial face. The vanes may have a circumferential periphery. The housing may form a part or more of a primary passage. The primary passage may be open to the vanes at the axial face. The housing may have an inlet passage that may communicate with the primary passage. The inlet passage may have a longitudinal axis that may be arranged generally axially with respect to the impeller. The method may also include diverting a portion or more of incoming air flow through the inlet passage away from the axial face of the impeller, away from the circumferential periphery of the vanes, or away from both the axial face and circumferential periphery.
One embodiment includes an air pump assembly that may include an impeller, a motor, a housing, and a diverter. The impeller may have numerous vanes, a first axial face, and a second axial face. The vanes may have a circumferential periphery. The motor may be connected to the impeller in order to rotate the impeller during use of the air pump assembly. The housing may surround the impeller. The housing may form a part or more of a first primary passage and a part or more of a second primary passage. The first primary passage may be open to the vanes at the first axial face, and the second primary passage may be open to the vanes at the second axial face. The housing may have an inlet passage that may communicate with the first and second primary passages. The inlet passage may have a longitudinal axis that may be arranged generally axially with respect to the impeller. The diverter may have a surface that may confront a portion or more of the axial extent of the circumferential periphery of the vanes via a radial space, may confront a portion or more of the radial extent of the vanes via an axial space, or may confront both the circumferential periphery and the vanes.
Other illustrative embodiments 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 illustrative embodiments of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
Illustrative embodiments of the present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:
The following description of the embodiment(s) is merely illustrative in nature and is in no way intended to limit the invention, its application, or its uses.
The figures illustrate several embodiments of an inlet design for a pump assembly that may improve fluid-flow efficiencies in the pump assembly compared to known inlet designs, meaning that the inlet designs disclosed herein may produce greater volumetric flow rate for a given power input. The overall size of the pump assembly may therefore be reduced if suitable and desirable for a particular application, while maintaining the same fluid-flow performance of the larger pump assembly with the known inlet design. Of course, the overall size of the pump assembly with the inlet designs disclosed herein need not be reduced, in which case the pump assembly would simply exhibit improved fluid-flow efficiencies and improved performance. The improvements may result in part from a reduction in turbulence of incoming fluid-flow, as will be described in greater detail below.
Referring to
The pump assembly 10 may be of the regenerative pump type. Referring to
Referring in particular to
The motor 14 may be located outside of the housing 16 and may be mounted to the housing, and may be connected to the impeller 12 in order to provide rotational drive thereto via its spinning shaft. The motor 14 is shown schematically in
The housing 16 may provide structural support for components of the pump assembly 10. The housing 16 may have different designs and constructions, including that shown in
Furthermore, and as mentioned, the housing 16 may partly define fluid-flow passages of the pump assembly 10. Still referring to
In this illustrated embodiment of the pump assembly 10, the inlet passage 40 may include a first inlet passage 52 and a second inlet passage 54. The first and second inlet passages 52, 54 may be defined in part by the diverter 18. The first inlet passage 52 may communicate with the first primary passage 44, and the second inlet passage 54 may communicate with the second primary passage 46. The first inlet passage 52 may direct incoming fluid-flow generally toward the first axial face 28 of the impeller 12 at the location of the vanes 22, and generally toward the first primary passage 44; and the second inlet passage 54 may direct incoming fluid-flow generally toward the second axial face 30 of the impeller at the location of the vanes and generally toward the second primary passage 46. Referring in particular to
The first and second primary passages 44, 46 may carry fluid-flow through the pump assembly 10 as the fluid-flow travels from the inlet passage 40 and to the outlet passage 42. Referring to
The diverter 18 may be a structure that may be used to veer, obstruct, or both veer and obstruct fluid-flow traveling through the inlet passage 40. In the case of an air pump assembly, air flow may principally make its way into the spaces located between neighboring individual vanes 22 via the first and second primary passages 44, 46 at the first and second axial faces 28, 30 of the impeller 12. It has been found that turbulent flow may be generated by initial impingement between incoming fluid-flow and the terminal ends 24 of the rotating vanes 22, and between incoming fluid-flow and the axial faces 28, 30 of the rotating impeller 12 at the location of the vanes. The turbulent flow may spread beyond the immediate region of initial impingement, and may interfere with and impede fluid-flow traveling in the first inlet passage 52 entering the first primary passage 44, may interfere with and impede fluid-flow in the second inlet passage 54 traveling axially past the impeller 12, may interfere with or impede fluid-flow traveling in the second inlet passage entering the second primary passage 46, or a combination thereof. The diverter 18 may therefore veer fluid-flow away from impingement with the vanes 22 and/or axial faces 28, 30, may be an obstruction to impingement, or both, to thereby limit or altogether eliminate turbulent flow otherwise generated thereat. Fluid-flow may then travel through the inlet passage 40 and into the first and second primary passages 44, 46 with greater ease, yielding improved fluid-flow efficiencies by as much as approximately eleven percent over some known inlet designs without diverters; fluid-flow improvements greater than eleven percent may also be possible.
The diverter 18 may have different designs and constructions, including that shown by a first embodiment in
Referring to
Further, the diverter 18 may have an inner or confrontation surface 82, and may have an outer surface 84 located at an opposite radial side of the diverter. The outer surface 84 may directly face bypassing fluid-flow F in the second inlet passage 54. The confrontation surface 82, on the other hand, may directly confront the terminal ends 24 of the vanes 22 and the circumferential periphery 26 via a radial space. The radial space may have a radial length B that may be maintained at a constant value along its axial extent between the first and second axial ends 78, 80, and may be maintained at a constant value along its circumferential extent between the first and second circumferential ends 74, 76 in which case the confrontation surface. may have a bowed and curved profile that follows the profile of the circumferential periphery 26. In another embodiment, for example, the confrontation surface 82 may be generally planar in which case the radial length B has a greater value at the first and second circumferential ends 74, 76 than at a circumferential centerpoint between the first and second circumferential ends. The radial length B may have a value that may be less than a radial thickness value of the diverter 18, and, in one example, the radial length B may be approximately 0.6 mm or 1.0 mm; in other examples, other values for the radial length B are possible including values less than 0.6 mm, greater than 1.0 mm, or between 0.6 mm and 1.0 mm. As shown best in
In use, fluid-flow F is drawn into the inlet passage 40 via the rotating impeller 12. A portion of the incoming fluid-flow F may be drawn into the first inlet passage 52 and may enter the first primary passage 44, and a portion of the incoming fluid-flow F may be drawn into the second inlet passage 54 and may enter the second primary passage 46. Also, a portion of the incoming fluid-flow F may pass through the opening 72 between the first and second inlet passages 52, 54. In the second inlet passage 54, bypassing fluid-flow F opposes the outer surface 84 of the diverter 18 as the fluid-flow makes its way to the second primary passage 46. Because the diverter 18—and in particular the confrontation surface 82—may obstruct impingement between the bypassing fluid-flow F in the second inlet passage 54 and the terminal ends 24 of the vanes 22, turbulent flow may be limited or altogether eliminated. The fluid-flow may therefore be substantially free to travel past the impeller 12 toward the closed bottom 56 substantially unimpeded by turbulent flow that would otherwise be generated without use of the diverter 18.
The second diverter 88 may be attached to or may extend from the cover piece 34—the attachment or extension is shown best in
Other embodiments—some of which have already been mentioned—that have not been described or shown are possible. For example, in any one of the first, second, third, or fourth embodiments, a third diverter could be provided. The third diverter could be located adjacent the second entrance of the second primary passage, could be arranged generally radially, and could generally directly confront and oppose the second axial face of the impeller to thereby limit or altogether eliminate generation of turbulent flow thereat. In another example, the diverter in any one of the embodiments could be attached to or could extend from the body piece instead or in addition to the cover piece.
The following is a description of select illustrative embodiments within the scope of the invention. The invention is not, however, limited to this description; and each embodiment and components, elements, and steps within each embodiment may be used alone or in combination with any of the other embodiments and components, elements, and steps within the other embodiments.
Embodiment one may include an air pump assembly. The air pump assembly may comprise an impeller, a housing, and a diverter. The impeller may have an axial face and a circumferential periphery. The housing may surround the impeller, and may form a part or more of a primary passage. The primary passage may be open to the impeller at the axial face. The housing may have an inlet passage that may communicate with the primary passage. The inlet passage may have a longitudinal axis that may be arranged generally non-orthogonally with respect to an axis of rotation of the impeller. The diverter may be located partially or more within the inlet passage. The diverter may have a surface that may confront the axial face of the impeller, may confront the circumferential periphery of the impeller, or may confront both the axial face and the circumferential periphery. During use of the air pump assembly, the diverter may inhibit generation of turbulent flow between incoming fluid-flow and the impeller where the surface confronts the impeller.
Embodiment two, which may be combined with embodiment one, further describes that the air pump assembly may include a motor connected to the impeller to rotate the impeller about the axis of rotation during use of the air pump assembly.
Embodiment three, which may be combined with any one of embodiments one and two, further describes that the axial face may include a first axial face and a second axial face. The primary passage may include a first primary passage and a second primary passage. The first primary passage may be open to the impeller at the first axial face, and the second primary passage may be open to the impeller at the second axial face. The inlet passage may communicate with the first and second primary passages.
Embodiment four, which may be combined with any one of embodiments one, two, and three, further describes that the housing may include a body piece and a cover piece that are attached together.
Embodiment five, which may be combined with any one of embodiments one, two, three, and four, further describes that the diverter may be arranged generally axially with respect to the impeller, and that the surface may confront the circumferential periphery of the impeller and may confront substantially the full axial extent of the circumferential periphery.
Embodiment six, which may be combined with any one of embodiments one, two, three, four, and five, further describes that the axial face may include a first axial face and a second axial face. The primary passage may include a first primary passage and a second primary passage. The first primary passage may be open to the impeller at the first axial face, and the second primary passage may be open to the impeller at the second axial face. The inlet passage may include a first inlet passage and a second inlet passage. The first inlet passage may communicate with the first primary passage and the second inlet passage may communicate with the second primary passage. The first and second inlet passages may be defined in part by the diverter. The diverter may extend upstream beyond the first axial face with respect to incoming fluid-flow. A portion or more of turbulence which may be generated between incoming fluid-flow in the first inlet passage and the first axial face may be obstructed by way of the diverter and may not substantially impede incoming fluid-flow in the second inlet passage.
Embodiment seven, which may be combined with any one of embodiments one, two, three, four, five, and six, further describes that the diverter may include a first diverter and a second diverter, and that the surface of the diverter may include a first surface of the first diverter and a second surface of the second diverter. The first surface may confront a portion or more of the circumferential periphery of the impeller, and the second surface may confront a portion or more of the first axial face of the impeller.
Embodiment eight, which may be combined with any one of embodiments one, two, three, four, five, six, and seven, further describes that the impeller may have numerous vanes. The diverter may be arranged generally radially with respect to the impeller. The surface may confront a portion or more of the radial extent of the vanes.
Embodiment nine may include a method. The method may comprise providing an air pump assembly that may comprise an impeller and a housing. The housing may surround the impeller: The impeller may have numerous vanes and an axial face. The vanes may have a circumferential periphery. The housing may form a part or more of a primary passage, and the primary passage may be open to the vanes at the axial face. The housing may have an inlet passage that may communicate with the primary passage. The inlet passage may have a longitudinal axis that may be arranged generally axially with respect to the impeller. The method may further comprise diverting a portion or more of incoming fluid-flow traveling through the inlet passage away from the axial face of the impeller, away from the circumferential periphery of the vanes, or away from both the axial face and the circumferential periphery.
Embodiment ten, which may be combined with embodiment nine, further describes diverting a portion or more of incoming fluid-flow by way of a diverter that may be located partially or more within the inlet passage. The diverter may have a surface that may confront a portion or more of the axial extent of the circumferential periphery of the vanes.
Embodiment eleven, which may be combined with any one of embodiments nine and ten, further describes diverting a portion or more of incoming fluid-flow by way of a diverter that may be located partially or more within the inlet passage. The axial face may include a first axial face and a second axial face. The primary passage may include a first primary passage and a second primary passage. The first primary passage may be open to the impeller at the first axial face, and the second primary passage may be open to the impeller at the second axial face. The inlet passage may include a first inlet passage and a second inlet passage. The first inlet passage may communicate with the first primary passage and the second inlet passage may communicate with the second primary passage. The first and second inlet passages may be defined in part by the diverter. The diverter may extend upstream beyond the first axial face with respect to incoming fluid-flow. A portion or more of turbulence that may be generated between incoming fluid-flow in the first inlet passage and the first axial face may be obstructed by way of the diverter and may not substantially impede incoming fluid-flow in the second inlet passage.
Embodiment twelve, which may be combined with any one of embodiments nine, ten, and eleven, further describes diverting a portion or more of incoming fluid-flow by way of a diverter. The diverter may be located partially or more within the inlet passage. The diverter may have a surface that may confront a portion or more of the radial extent of the vanes at the axial face of the impeller.
Embodiment thirteen, which may be combined with any one of embodiments nine, ten, eleven, and twelve, further describes diverting a portion or more of incoming fluid-flow by way of a first diverter and a second diverter. The first diverter may be located partially or more within the inlet passage, and the second diverter may be located partially, or more within the inlet passage. The first diverter may have a first surface that may confront a portion or more of the axial extent of the circumferential periphery of the vanes, and the second diverter may have a second surface that may confront a portion or more of the radial extent of the vanes at the axial face of the impeller.
Embodiment fourteen, which may be combined with any of the previous embodiments one through thirteen, may include an air pump assembly. The air pump assembly may comprise an impeller, a motor, a housing, and a diverter. The impeller may have numerous vanes, a first axial face, and a second axial face. The vanes may have a circumferential periphery. The motor may be connected to the impeller in order to rotate the impeller when the air pump assembly is in use. The housing may surround the impeller. The housing may form a part or more of a first primary passage. The first primary passage may be open to the vanes at the first axial face. The housing may form a part or more of a second primary passage. The second primary passage may be open to the vanes at the second axial face. The housing may have an inlet passage that may communicate with the first and second primary passages. The inlet passage may have a longitudinal axis that may be arranged generally axially with respect to the impeller. The diverter may have a surface that may confront a portion or more of the axial extent of the circumferential periphery of the vanes by way of a radial space, may confront a portion or more of the radial extent of the vanes by way of an axial space, or may confront both.
The above description of embodiments of the invention is merely illustrative in nature and, thus, variations thereof are not to be regarded as a departure from the spirit and scope of the invention.
