Patent Application
20180274551
None.
This application is directed to forced induction devices and, in particular, forced induction devices of varied capacities.
A forced induction device, such as a turbocharger, provides compressed air to an internal combustion engine. The forced induction device typically includes a compressor wheel that is rotated within a compressor housing to draw ambient air in and expel compressed air out. The compressor housing generally includes a volute that functions as an outlet, an inlet extending axially from the volute, and a cavity surrounded by the volute and in fluidic communication between the inlet and the volute. As the compressor wheel is rotated within the cavity, ambient air is drawn in axially through the inlet at an inducer end of the compressor wheel, and is expelled out radially through the volute at an exducer end of the compressor wheel.
The compressor wheel may be characterized by the diameters of the of the inducer end (i.e., the inducer diameter (DI)) and the exducer end (i.e., exducer diameter (DE)), as well as by trim, which is a ratio of the areas of the inducer end and the exducer end. More particularly, trim is the ratio of the square of the inducer diameter to the exducer diameter times 100 (i.e., DÎ2/DÊ2×100). For example, a compressor wheel having an inducer diameter of 60 mm and an exducer diameter of 80 mm has a trim of 56.3 (i.e., 60̂2/80̂2×100).
The capacity (e.g., flow capacity or flow rate) of the compressor wheel is impacted by the inducer diameter. For compressor wheels that are otherwise the same (i.e., having a common exducer diameter), those with higher inducer diameter (and, thereby, higher trim) will generally have higher capacity than those with lower inducer diameters (and, thereby, lower trim). For example, the example compressor wheel described above would have higher capacity if it had a larger inducer diameter (e.g., 63 mm, or 62 trim) or lower capacity if it had a smaller inducer diameter (e.g., 58 mm, or 52.6 trim).
Thus, to achieve different capacities, a line of compressor wheels may have a common exducer diameter, while having different inducer diameters. The different compressor wheels of the line may be identified by their different trims.
However, to produce forced induction devices with different capacities, different tooling and/or additional machining operations are required to form the compressor wheels with different trim, and further tooling and/or additional machining operations may also be required to form compressor housings that physically accommodate compressor wheels with different trims. This additional tooling expense may be particularly high for compressor wheels formed of composite materials (e.g., by injection molding) by requiring different molds for each trim of the compressor wheels.
One aspect of the disclosed embodiments is directed to a forced induction device that includes a compressor wheel, a housing, and an intake insert. The compressor wheel has an inducer diameter and an exducer diameter. The housing includes a housing cover member having a central portion and a housing intake portion extending from the central portion. The central portion defines a compressor cavity in which the compressor wheel rotates and having a cavity inlet diameter larger than the inducer diameter. The intake insert defines a conduit extending therethrough from a proximal end to a distal end of the intake insert. The proximal end is received by the housing intake portion with the conduit in fluidic communication with the compressor cavity. At the proximal end, the conduit the conduit has a proximal inner diameter that is less than cavity inlet diameter and the inducer diameter, and the distal end is configured to connect to a coupling portion of an air source.
The forced induction device may further include an electric motor that rotates the compressor wheel. The proximal end of the intake insert may extend radially from the proximal inner diameter to a proximal outer diameter of the intake insert, such that material of the proximal end spans across the cavity inlet diameter and the inducer diameter. The housing cover member may form a shoulder extending radially outward from the compressor cavity to the housing intake portion, and the proximal end of the intake insert may engage the shoulder. At the distal end of the intake insert, the conduit may have a distal inner diameter that is larger than the proximal inner diameter, the cavity inlet diameter, and the inducer diameter. The intake insert may include a proximal portion terminating at the proximal end and a distal portion terminating at the distal end with the proximal portion being received by a female recess defined by the housing intake portion, and the distal portion protruding from the housing intake portion to be coupled to an air source. The compressor wheel may be formed of a composite material.
According to another aspect, a method is provided for producing forced induction devices of different capacities. The method includes providing for a first forced induction device a first compressor wheel of a common compressor wheel design, a first compressor housing cover member of a common cover member design, and a first intake insert of a first intake insert design having a first restriction feature for restricting flow through the first intake insert. The method also includes assembling the first forced induction device by assembling the first compressor wheel, the first compressor housing cover member, and the first intake insert together. The method also includes providing for a second forced induction device a second compressor wheel of the common compressor wheel design, a second compressor housing cover member of the common cover member design, and a second intake insert of a second intake insert design that differently restricts flow than does the first intake insert. The method also includes assembling the second forced induction device by assembling the second compressor wheel, the second compressor housing cover member, and the second intake insert together. The first forced induction device has a different capacity than the second forced induction device.
According to another aspect, a forced induction device includes a compressor wheel, a compressor housing, and an intake insert. The compressor wheel has an inducer diameter. The compressor housing has an intake. The compressor wheel is rotatable within the housing. The intake insert defines a conduit with a minimum diameter that is less than the inducer diameter to restrict air flow to the compressor wheel. A design of the intake insert is selected from among multiple different intake insert designs that differ each other by having different minimum inner diameters. The intake insert is permanently coupled to the intake of the compressor, and is connectable to an air source.
The description herein makes reference to the accompanying drawings, wherein like reference numerals refer to like parts throughout several views, and wherein:
Disclosed herein are forced induction devices and methods of producing forced induction devices having different capacities (e.g., effective trim), while using common wheel and housing designs. For example, a forced induction device includes an intake insert (e.g., insert or intake coupling), which functions to restrict air flow into the forced induction device, for example, by having a smaller inner diameter than an inducer diameter of the compressor wheel. Further, a method is provided for producing forced induction devices with different capacities, which include compressor wheels and compressor housings of common designs, includes selecting different inserts that reduce the inlets sizes of the different forced induction devices to achieve the different capacities.
Referring now to
The drive source 12 is coupled to the compressor wheel 20 with a shaft 22. The drive source 12 is preferably an electric motor (depicted schematically in
The compressor wheel 20 is configured to draw air into the forced induction device 10 from an air source 80 (e.g., at ambient pressure), compress the air, and expel the air from the forced induction device 10 at an elevated pressure. The compressor wheel 20 is a unitary component formed of a composite material (e.g., fiber-filled polymer, such as glass-filled nylon) and may be formed with a molding or other suitable process (e.g., injection molding or insert molding).
As shown in
As shown in
The housing cover 42 generally includes a central portion 44 (e.g., compressor cavity, inner, or interior portion), a housing intake portion 46 (e.g., intake, annular, extension, or coupling portion) extending axially from the central portion 44, and a volute portion 48 (e.g., outer, exterior, or outlet portion) surrounding the central portion 44. The housing cover 42 is formed as a unitary component or member (e.g., via a metal casting operation), such that the central portion 44, the housing intake portion 46, and the volute portion 48 are formed integrally with each other. Alternatively, the housing cover 42 comprise multiple members.
The central portion 44 of the housing cover 42 defines a compressor cavity 44a in which the compressor wheel 20 rotates. The central portion 44 has an inner periphery 44b (e.g., shroud) shaped with an inner profile (e.g., inner or cavity profile or curvature) that is complementary to the outer profiles of the blades 26. These complementary profiles allow the compressor wheel 20 to rotate within the compressor cavity 44a with the blades 26 passing in close proximity to the inner periphery 44b of the central portion 44. Furthermore, the inner periphery 44b may be sized relative to the blades 26 to allow for increased radial growth of the compressor wheel 20 that may result from the compressor wheel 20 being formed from composite materials that are generally less stiff and may further decrease in stiffness at operating temperatures as compared to metal compressor wheels.
The inner periphery 44b of the central portion 44 defines an inlet (e.g., cavity inlet) to the compressor cavity 44a. The cavity inlet may be considered the axial end of the compressor cavity 44a, for example, where the inner periphery 44b terminates to form a shoulder 46e (discussed below). The cavity inlet has a diameter DCI (e.g., cavity inlet diameter) that is slightly larger than the inducer diameter (DI) of the compressor wheel 20, which allows for receipt and rotation of the compressor wheel 20 within the compressor cavity 44a.
The housing intake portion 46 of the housing cover 42 is an annular portion that extends axially from the central portion 44 and terminates at an axial end 46a thereof (e.g., housing intake portion end or face), which may be substantially planar. The housing intake portion 46 receives and is coupled to the intake insert 60 (e.g., in a permanent manner). The housing intake portion 46 protrudes from the central portion 44 and/or the volute portion 48 a short but sufficient distance to receive and couple to the intake insert 60. For example, the housing intake portion 46 may have an axial length (e.g., measured from the shoulder 46e) that is less than two times (e.g., less than one time) the inducer diameter (DI) and/or the cavity inlet diameter (DCI).
The housing intake portion 46 has an inner periphery 46b that is substantially concentric with the compressor cavity 44a and the cavity inlet. The inner periphery 46b defines a female recess 46c for receipt of the intake insert 60 therein. The inner periphery 46b of the housing intake portion 46 has an inner diameter (DII) (e.g., intake inner diameter) that at its minimum is greater than the cavity inlet diameter (DCI). The inner periphery 46b of the housing intake portion 46 may vary in diameter moving axially away from the central portion 44 of the housing cover 42, which may create one or more circumferential cavities 46d (labeled in
The housing cover 42 forms the shoulder 46e (e.g., shoulder surface) that extends radially outward from the inner periphery 44b of the central portion 44 to the inner periphery 46b of the housing intake portion 46. The shoulder 46e may, as shown, extend perpendicular to the axis of the compressor wheel 20 to provide a flat surface (e.g., planar surface), or may extend radially outward in another manner (e.g., curved or straight) to provide a differently shaped surface.
Referring to
The intake insert 60 is a generally tubular member that is received by and coupled to the housing intake portion 46 of the housing cover 42. The intake insert 60 may, for example, be a unitary member formed of a suitable material (e.g., rigid polymer or metal) according to a suitable method (e.g., injection molding, casting, machining, etc.), which defines a conduit 68 (described in further detail below). The intake insert 60 extends between a proximal end 62a (e.g., outlet end) and a distal end 64a (e.g., inlet end) thereof. When connected to the compressor housing 40, the intake insert 60 extends in an axial direction away from the compressor housing 40 (as shown in
The intake insert 60 includes the proximal portion 62 (referenced above) (e.g., outlet, received/receivable, or inserted/insertable portion) and a distal portion 64 (e.g., inlet, air intake, protruding, or extending portion). The proximal portion 62 is a male portion received within the housing intake portion 46 of the housing cover 42 and terminates at the proximal end 62a of the intake insert 60. The proximal portion 62 includes the outer periphery 62b (referenced above) having an outer diameter (DPO) (e.g., proximal outer diameter) that facilitates receipt of the intake insert 60 into the female recess 46c of the housing intake portion 46 of the housing cover 42. The proximal outer diameter (DPO) may, for example, provide an interference fit between the intake insert 60 and the housing intake portion 46 of the housing cover 42 (e.g., the proximal outer diameter (DPO) being slightly smaller than the minimum of the intake inner diameter (DII) of the female recess 46c of the housing intake portion 46). The proximal outer diameter (DPO) of the proximal portion 62 may be substantially constant over the proximal portion 62.
When the intake insert 60 is inserted into the female recess 46c of the housing intake portion 46 of the compressor housing 40, the proximal end 62a may directly abut the shoulder 46e of the compressor housing 40 (as shown), may abut or compress another member interposed therebetween (e.g., seal or gasket), or may be spaced apart therefrom.
The distal portion 64 of the intake insert 60 extends from the proximal portion 62 until terminating at the distal end 64a of the intake insert 60. The distal portion 64 is a male portion configured to be received by the coupling portion of the air source 80. The distal portion 64 has an outer periphery 64b with an outer diameter (DDO) (e.g., distal outer diameter) that facilitates receipt of the intake insert 60 into the coupling portion of the air source 80. The distal outer diameter (DDO) may, for example, provide an interference fit between the intake insert 60 and the coupling portion of the air source 80. The distal outer diameter (DDO) of the distal portion 64 is greater than the intake inner diameter (DII) at various locations of the housing intake portion 46 and may be may be substantially constant (as shown). The distal portion 64 may additionally include one or more circumferential protrusions 64c (e.g., barbs, or flanges) that extend radially outward from the outer periphery 64b adjacent the distal end 64a, which facilitate coupling (e.g., preventing removal) from the coupling portion (e.g., an elastomeric tubular member or segment) of the air source 80.
The intake insert 60 may additionally include a circumferential flange 66 that is positioned at an intermediate axial location (e.g., between the proximal portion 62 and the distal portion 64). The circumferential flange 66 protrudes radially outward of the outer periphery 62b of the proximal portion 62 and may also protrude radially outward of the outer periphery 64b of the distal portion 64.
With the distal portion 64 functioning as a male member to be received within the coupling portion of the air source 80, as opposed to functioning as a female recess that receives the coupling portion, the coupling portion of the air source 80 does not further restrict air flow over the flow restriction provided by the intake insert 60 as described below. Alternatively, the intake insert 60 may function as a female recess, while an inner diameter of the coupling portion of the air source is greater than or equal to a minimum inner diameter of a conduit 68 formed by the intake insert 60 as described below.
When the intake insert 60 is inserted into the female recess 46c of the housing intake portion 46 of the compressor housing 40, the circumferential flange 66 may directly abut the axial end 46a of the housing intake portion 46 of the compressor housing 40, may abut or compress another member interposed therebetween (e.g., seal or gasket), or may be spaced apart therefrom (as shown). Thus, axial insertion of the intake insert 60 into the female recess 46c may be limited by direct or indirect engagement of the proximal end 62a of the intake insert 60 with the shoulder 46e of the compressor housing 40 and/or of the circumferential flange 66 with the axial end 46a of the housing intake portion 46 of the compressor housing 40.
The intake insert 60 additionally defines the conduit 68 (e.g., bore) that extends therethrough from the proximal end 62a to the distal end 64a. The intake insert 60 has an inner periphery 68a that defines the conduit 68. At the proximal end 62a, the inner periphery 68a has an inner diameter (DPI) (e.g. proximal inner diameter) that is less than the cavity inlet diameter (DCI) and may also be less than the inducer diameter (DI) of the compressor wheel 20 (as shown in
Because the proximal outer diameter (DPO) is greater than and the proximal inner diameter (DPI), which is in turn less than the cavity inlet diameter (DCI) and the inducer diameter (DI), material forming the proximal end 62a (e.g., a wall or wall thickness) spans radially across the inner periphery 44b of the central portion 44 of the compressor housing 40 (e.g., where the inner periphery 44b intersects the shoulder 46e). The wall of the proximal end 62a also spans radially across radially outer ends of the blades 26 at the inducer end 20a of the compressor wheel 20.
With the proximal inner diameter (DPI) of the conduit 68 being less than the cavity inlet diameter (DCI) and the inducer diameter (DI), the proximal inner diameter (DPI) functions as a flow restriction feature that restricts air flow through the conduit 68 of the intake insert 60 into the compressor wheel 20. Provision of a flow restriction feature has a similar effect to reducing the inducer diameter (DI) or trim of the compressor wheel 20. For example, the proximal inner diameter (DPI) may be between approximately 0% (e.g., no flow restriction) and 30% (e.g., high flow restriction) less than that cavity inlet diameter (DCI) and/or the inducer diameter (DI). Thus, by reducing the proximal inner diameter (DPI) of the conduit 68, the capacity (e.g., flow capacity or flow rate) of the forced induction device 10 may be reduced without modification of the compressor wheel 20 or the compressor housing 40 and without the expense of different tooling or machining of compressor wheels and housing of different shapes. That is, different forced induction devices may have different capacities while still using a compressor wheel of a common compressor wheel design and a housing cover 42 of a common housing cover design (e.g., housing design, cover member design, or similar). Alternative to different minimum inner diameters of the conduit 68 (e.g., different proximal inner diameters (DPI)), different levels of flow restriction may be provided by other features (e.g., different shapes of or physical features in the conduit 68).
The intake insert 60 used for a particular application may be selected from various different designs of intake inserts (e.g., intake insert designs). The various different intake insert designs may differ based on how restrictive they are of air flow to the compressor wheel 20. For example, the different designs may range from being non-restrictive to highly restrictive, which may be due to having different minimum inner diameters (e.g., different proximal inner diameters (DPI)) of the conduit 68. The various different intake insert designs (and resultant intake inserts formed thereby) may otherwise be the same (e.g., differing by only the different restriction features).
As shown in
At the distal end 64a, the inner periphery 68a of the conduit 68 has an inner diameter (DDI) (e.g., distal inner diameter) that is greater than (as shown) or equal to the proximal inner diameter (DPI). As a result, the inner diameter of the inner periphery 68a may decrease moving from the distal end 64a to the proximal end 62a. The inner diameter of the inner periphery 681a may reduce at a constant angle over a portion of the intake insert 60 (as shown) (e.g., terminating at the proximal end 62a as shown). The diameter of the inner periphery 68a may be constant over another portion of the intake insert 60 (e.g., terminating at the distal end 64a).
By having the distal inner diameter (DDI) be greater than (or the same as) the proximal inner diameter (DPI), the distal inner diameter (DDI) does not further restrict flow through the conduit 68 of the intake insert 60 over the restriction otherwise caused by the smaller or equally-sized proximal inner diameter (DPI). The distal inner diameter (DDI) may also be greater than (or the same as) the cavity inlet diameter (DCI) of the central portion 44 of the housing cover 42 and the inducer diameter (DI) of the compressor wheel 20, such that distal inner diameter (DDI) of the conduit 68 does not further restrict flow to the compressor wheel 20 over restriction otherwise caused by the cavity inlet diameter (DCI) and the inducer diameter (DI).
As shown in
In a second step 720, a first intake insert is provided with a first intake insert design having a first flow restriction feature that restricts air flow through the first intake insert. For further details of the intake insert, refer to the discussion above of the intake inserts 60, 160, and 260.
In a third step 730, the first forced induction device is assembled by assembling the first compressor wheel, the first compressor housing member, and the first intake insert to each other. During assembly, the first intake insert may be connected (e.g., permanently) to the housing member before the housing member the first compressor wheel is assembled thereto.
In a fourth step 740, the first through third steps are repeated for a second compressor wheel having a second compressor wheel of the common compressor wheel design, a second compressor housing member of the common compressor housing member design, and a second intake insert of a second intake insert design. The second intake insert design differently restricts flow through the second intake insert than the first intake insert design of the first intake insert. For example, the second intake insert design may include no flow restriction feature, such that the second intake insert is less restrictive to air flow therethrough than the first intake insert. Alternatively, the second intake insert design may include a second restriction feature that is more restrictive that the first restriction feature (e.g., a smaller proximal inner diameter (DPI)).
In a fifth step 750, instead of or in addition to the fourth step 740, the first through third steps are repeated for a third compressor wheel having a third compressor wheel of the first compressor wheel design, a third compressor housing of the first compressor housing design, and a third intake insert of a third intake insert design. The third intake insert design differently restricts flow through the third intake insert than the first and second intake insert designs of the first and second intake inserts. For example, the third intake insert design may include no flow restriction feature, such that the third intake insert is less restrictive to air flow therethrough than the first intake insert. Alternatively, the third intake insert design may include a third restriction feature that is more restrictive to air flow through the third intake insert than the first restriction feature and the second restriction feature (e.g., a smaller proximal inner diameter (DPI)).
In a sixth step 760 any of the first, second, or third forced induction devices, respectively, may be connected to an air source via the first, second, or third intake insert coupling thereof.
It is to be understood that the present disclosure is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.
