Patent Description:
Some vehicles include a turbocharger, supercharger and/or other devices for boosting the performance of an internal combustion engine. More specifically, these devices can increase the engine's efficiency and power output by forcing extra air into the combustion chamber of the engine.

In some cases, the vehicle may include an electrically driven compressor, or e-charger, for these purposes. However, conventional e-chargers can be bulky, cost prohibitive, and/or may present other issues.

Thus, it is desirable to provide an e-charger that is more compact than conventional e-chargers. Also, it is desirable to provide an e-charger that provides cost savings compared to conventional e-chargers. Other desirable features and characteristics of the present disclosure will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background discussion.

Documents cited during prosecution include <CIT>; <CIT>; <CIT>; and <CIT>.

Aspects and embodiments of the invention are defined in the appended claims. According to a first aspect, there is provided an electrically driven compressor assembly that includes a shaft and a compressor wheel that is supported on the shaft. The compressor assembly also includes an electric motor with a stator and a rotor. The electric motor is configured to rotate the shaft and the compressor wheel. The compressor assembly additionally includes a housing assembly configured to house the stator, the rotor, and at least part of the shaft. The housing assembly includes a first member and a second member, the second member being radially overlapped and received within an open first end of the first member of the housing assembly. The compressor assembly additionally includes a bearing configured to support rotation of the shaft relative to the second member of the housing assembly relative to the second member of the housing assembly about an axis of rotation. Moreover, the compressor assembly includes a dampener disposed between the first member and the second member of the housing assembly. The dampener is configured to elastically deform to provide dampening of a force transferred between the first member and the second member of the housing assembly.

According to a second aspect, there is provided a method of manufacturing an electrically driven compressor assembly. The method includes providing a first member and a second member of a housing assembly. The method also includes supporting, with a bearing, a shaft on the second member for rotation relative to the second member. A compressor wheel is supported on the shaft. The method further includes housing an electric motor within the housing assembly, with the second member being radially overlapped and received within an open first end of the first member of the housing assembly. The electric motor is configured to rotate the shaft and the compressor wheel. Moreover, the method includes attaching the first member and the second member together with a dampener between the first member and the second member. The dampener is configured to elastically deform to provide dampening of a force transferred between the first member and the second member of the housing assembly.

The present disclosure will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:.

The following detailed description is merely exemplary in nature and is not intended to limit the present disclosure or the application and uses of the present disclosure. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.

Broadly, example embodiments disclosed herein include a damping system of an electrically powered compressor (i.e., an e-charger). One or more dampeners may be provided for damping forces translating through the e-charger and/or supporting structure(s).

In particular, the dampener may be resiliently deformable. The dampener may also include one or more surface features, shapes, dimensions, materials, and/or other elements that provide improved dampening. Additionally, the dampener may be incorporated within the damping system in ways that improve its damping function. For example, the dampener may be disposed between different members of a housing assembly, and the dampener may be supported by these members to provide effective damping of the forces transferring through the housing assembly. Furthermore, the damping system may allow certain types of bearings to be incorporated in the e-charger for added benefit. Moreover, the damping system may provide manufacturing efficiencies due to one or more features of the present disclosure. Additional details of the present disclosure will be discussed below.

<FIG> is a schematic view of an example e-charger <NUM> of the present disclosure. Generally, the e-charger <NUM> may include an e-charger housing assembly <NUM> and a shaft <NUM>. The shaft <NUM> is configured to rotate within the e-charger housing assembly <NUM> about an axis <NUM> of rotation. A compressor wheel <NUM> may be mounted on the shaft <NUM>. The e-charger <NUM> may also include an electric motor <NUM> that is configured to rotate the shaft <NUM> and compressor wheel <NUM>. Accordingly, the compressor wheel <NUM> may receive an inlet air flow <NUM> and output a pressurized air stream <NUM> to a downstream component.

In some embodiments, the e-charger <NUM> may be provided within a vehicle. Additionally, in some embodiments, the e-charger <NUM> may be incorporated in a vehicle that includes a turbocharger <NUM>.

The turbocharger <NUM> may be conventional and may include a turbocharger housing <NUM> and a rotor <NUM>. The rotor <NUM> is configured to rotate within the turbocharger housing <NUM> about an axis of rotor rotation <NUM>.

The turbocharger <NUM> includes a turbine section <NUM> configured to circumferentially receive a high-pressure and high-temperature exhaust gas stream <NUM> from an engine (e.g., from an exhaust manifold <NUM> of an internal combustion engine <NUM> or other type of engine). A turbine wheel <NUM> (and thus the rotor <NUM>) is driven in rotation around the axis of rotor rotation <NUM> by the high-pressure and high-temperature exhaust gas stream <NUM>, which becomes a lower-pressure and lower-temperature exhaust gas stream <NUM> that is released into a downstream exhaust pipe <NUM>.

The turbocharger <NUM> also includes a compressor section <NUM> with a compressor wheel <NUM> that is driven in rotation by the exhaust-gas driven turbine wheel <NUM>. The compressor wheel <NUM> is configured to compress received input air <NUM> into a pressurized air stream <NUM>. Due to the compression process, the pressurized air stream <NUM> is characterized by an increased temperature, over that of the input air <NUM>.

The air stream <NUM> may be channeled through an air cooler <NUM> (i.e., an intercooler), such as a convectively cooled charge air cooler. The air cooler <NUM> may be configured to dissipate heat from the air stream <NUM>, increasing its density. The resulting cooled and pressurized air stream <NUM> is channeled into an intake manifold <NUM> of the internal combustion engine <NUM>, or alternatively, into a subsequent-stage, in-series compressor. The operation of the system may be controlled by an ECU <NUM> (engine control unit) that connects to the remainder of the system via communication connections <NUM>.

As represented schematically in <FIG>, the e-charger <NUM> may be disposed upstream of the turbocharger <NUM>. For example, the air stream <NUM> output from the e-charger <NUM> may mix with the exhaust gas stream <NUM> and/or otherwise provide air input to the turbine section <NUM> to turn the turbine wheel <NUM> and, thus, rotate the compressor wheel <NUM> of the turbocharger <NUM>. However, it will be appreciated that the e-charger <NUM> may be incorporated differently within the vehicle without departing from the scope of the present disclosure. For example, the e-charger <NUM> may be disposed downstream of the turbocharger <NUM> in some embodiments. In both cases, the e-charger <NUM> may feed air to the engine <NUM>. The e-charger <NUM> may reduce transient time and turbo lag. The e-charger <NUM> may also provide benefits, such as reduced emissions, improved fuel efficiency, etc. Also, the size of the turbocharger <NUM> may be reduced due to the inclusion of the e-charger <NUM>.

Also, it will be appreciated that the e-charger <NUM> may be incorporated in a system that does not include a turbocharger <NUM>. For example, in additional embodiments, the e-charger <NUM> may be configured to feed air to a fuel cell of a vehicle.

In addition, it will be appreciated that the term "e-charger" as used herein is to be interpreted broadly, for example, to include devices with an electrically driven compressor wheel regardless of where the e-charger is incorporated, the type of system in which the e-charger is incorporated, etc. It will also be appreciated that the e-charger of the present disclosure may also be referred to as an electrically driven compressor assembly. Also, the e-charger of the present disclosure may be configured as an electric supercharger, as a hybrid turbocharger, as an e-boost device, or other related component.

Referring now to <FIG> and <FIG>, the e-charger <NUM> will be discussed in greater detail according to example embodiments. As mentioned above, the e-charger <NUM> may generally include the housing assembly <NUM>, the shaft <NUM>, the compressor wheel <NUM>, and the electric motor <NUM>.

The shaft <NUM> may be substantially cylindrical and may include a first end <NUM>, a second end <NUM>, and an intermediate segment <NUM> extending between the first and second ends <NUM>, <NUM>. The compressor wheel <NUM> may be fixed to the shaft <NUM> and supported thereon adjacent the first end <NUM>. The compressor wheel <NUM> may include a plurality of radiallyextending blades <NUM>.

The electric motor <NUM> may include a rotor <NUM>. The rotor <NUM> may be fixed to the intermediate segment <NUM> of the shaft <NUM>. Accordingly, the rotor <NUM> and the shaft <NUM> may rotate as a unit about the axis <NUM> of rotation. The electric motor <NUM> may also include a stator <NUM> as shown in <FIG>. (The stator <NUM> is hidden in <FIG> to better illustrate other components. ) The stator <NUM> may be cylindrical and hollow such that the intermediate segment <NUM> of the shaft <NUM> and the rotor <NUM> are received within the stator <NUM>.

The electric motor <NUM> may further include an electric module <NUM>. The electric module <NUM> may include electrical equipment, such as a converter, circuitry, a controller for the electric motor <NUM>, and/or other components. Thus, during operation, the electric module <NUM> may control the electric motor <NUM> such that the shaft <NUM> and the rotor <NUM> rotate about the axis <NUM> of rotation relative to the stator <NUM> in order to drivingly rotate the compressor wheel <NUM>.

The housing assembly <NUM> may include a number of components that are assembled together to at least partially house, surround, enclose, and/or encapsulate the compressor wheel <NUM>, the shaft <NUM>, and the electric motor <NUM>. The housing assembly <NUM> may be configured to provide certain advantages with regards to manufacturability and/or other factors as will be discussed in detail below.

As shown in <FIG>, the housing assembly <NUM> may generally include a compressor section <NUM>, which houses the compressor wheel <NUM>. The housing assembly <NUM> may also generally include an e-module section <NUM>, which houses the electric module <NUM>. Also, the housing assembly <NUM> may generally include a motor section <NUM>, which houses the electric motor <NUM>.

The compressor section <NUM> of the housing assembly <NUM> may include a volute member <NUM>. The volute member <NUM> may include an inlet <NUM> that may be directed along the axis <NUM>. The volute member <NUM> may also include an outlet (not shown) which provides air along the air stream <NUM> (<FIG>). The volute member <NUM> may further include an interior surface <NUM> with a volute shape extending circumferentially about the axis <NUM>. During operation of the e-charger <NUM>, the interior surface <NUM> may cooperate with the blades <NUM> of the compressor wheel <NUM> to compress air along the air stream <NUM>. The volute member <NUM> may be fixed on one end of the motor section <NUM> of the housing assembly <NUM>. Accordingly, the volute member <NUM> and the end of the motor section <NUM> may cooperate to house the compressor wheel <NUM> and the first end <NUM> of the shaft <NUM>.

As shown in <FIG>, the e-module section <NUM> may be fixed on an opposite end of the motor section <NUM>. The e-module section <NUM> may include a shell <NUM> and an end cap <NUM>. The shell <NUM> may be cylindrical and hollow with a first end <NUM> and a second end <NUM>. The first end <NUM> may be fixed to the motor section <NUM>. The end cap <NUM> may be disc-shaped and may be fixed to the second end <NUM> of the shell <NUM> to close off the second end <NUM>. Accordingly, the shell <NUM>, the end cap <NUM>, and the end of the motor section <NUM> may cooperate to substantially encapsulate the electric module <NUM>.

The motor section <NUM> of the housing assembly <NUM> may include an outer shell member <NUM>, a first member <NUM>, a second member <NUM>, and a third member <NUM>. In some embodiments, the outer shell member <NUM> may cooperate with the volute member <NUM> and the e-module section <NUM> to define the exterior of the e-charger <NUM>. Also, in some embodiments, the first member <NUM> may be referred to as a "stator housing" because it substantially surrounds the stator <NUM>. Furthermore, the second member <NUM> and the third member <NUM> may be referred to as "bearing plates" or "end caps". In some embodiments, the first member <NUM>, the second member <NUM>, and the third member <NUM> may cooperate to substantially encapsulate the rotor <NUM> and the stator <NUM>.

In some embodiments, the outer shell member <NUM> may be generally cylindrical and may be hollow so as to encircle the axis <NUM> in the circumferential direction. The outer shell member <NUM> may include a first end <NUM> and a second end <NUM>. The first end <NUM> may be fixed to the volute member <NUM>. For example, as shown in <FIG>, the volute member <NUM> may radially overlap the outer diameter surface of the first end <NUM> of the outer shell member <NUM>. The second end <NUM> of the outer shell member <NUM> may be fixed to the e-module section <NUM>. For example, the shell <NUM> of the e-module section <NUM> may radially overlap the outer diameter surface of the second end <NUM> of the outer shell member <NUM>.

The first member <NUM> of the housing assembly <NUM> may also be generally cylindrical and may be hollow. Accordingly, the first member <NUM> may encircle the axis <NUM> in the circumferential direction and may extend longitudinally along the axis <NUM>. The first member <NUM> may include a first end <NUM>, a second end <NUM>, and an intermediate portion <NUM> that extends along the axis <NUM> between the first and second ends <NUM>, <NUM>.

As shown in <FIG> and <FIG>, the first end <NUM> of the first member <NUM> may be an annular flange that projects in a longitudinal direction along the axis <NUM> from a front vertical face <NUM> of the intermediate portion <NUM>. The first end <NUM> may include an inner diameter surface <NUM>, which faces radially inward, and an outer diameter surface <NUM>, which faces radially outward.

As shown in <FIG>, the second end <NUM> of the first member <NUM> may be an annular flange that projects from a rear vertical face <NUM> of the intermediate portion <NUM>. The second end <NUM> may include an inner diameter surface <NUM>, which faces radially inward, and an outer diameter surface <NUM>, which faces radially outward.

The second member <NUM> of the housing assembly <NUM> may be generally disc-shaped. As shown in <FIG>, the second member <NUM> may include a central opening <NUM> that is substantially centered on the axis <NUM>. The second member <NUM> may also include an outer face <NUM> that faces the compressor wheel <NUM> and an inner face <NUM> that faces the electric motor <NUM>. Moreover, as shown in <FIG> and <FIG>, the second member <NUM> may include a first outer portion <NUM> that is supported against the volute member <NUM> and the outer shell member <NUM>. In some embodiments, the housing assembly <NUM> may also include a ring <NUM> that is disposed between the first outer portion <NUM> and the outer shell member <NUM>. The second member <NUM> may further include a second outer portion <NUM> that is disposed adjacent the first end <NUM> of the first member <NUM> of the housing assembly <NUM> and the front vertical face <NUM> of the first member <NUM> of the housing assembly <NUM>. The second outer portion <NUM> is radially overlapped and received within the open first end <NUM> of the first member <NUM> of the housing assembly <NUM>. Accordingly, the second member <NUM> may allow passage of the first end <NUM> of the shaft <NUM> from the motor section <NUM> to the compressor section <NUM> of the housing assembly <NUM>. The second member <NUM> may also support the shaft <NUM> for rotation within the housing assembly <NUM> as will be discussed in detail below. Moreover, the second member <NUM> may act as a barrier between the compressor wheel <NUM> and the electric motor <NUM>.

The third member <NUM> of the housing assembly <NUM> may be generally disc-shaped. The third member <NUM> may include a central opening <NUM> that is substantially centered on the axis <NUM>. The third member <NUM> may also include an outer face <NUM> that faces the electric module <NUM> and an inner face <NUM> that faces the electric motor <NUM>. Moreover, the third member <NUM> may include a first outer portion <NUM> that is supported against the outer shell member <NUM>. In some embodiments, the housing assembly may also include a ring <NUM> that is disposed between the first outer portion <NUM> and the outer shell member <NUM>. Additionally, the third member <NUM> may include a second outer portion <NUM> that is disposed adjacent the second end <NUM> of the first member <NUM> of the housing assembly <NUM>. In some embodiments, the second outer portion <NUM> may be radially overlapped and received within the open second end <NUM> of the first member <NUM> of the housing assembly <NUM>. The third member <NUM> may also support the shaft <NUM> for rotation within the housing assembly <NUM> as will be discussed in detail below. Moreover, the third member <NUM> may act as a barrier between the electric motor <NUM> and the electric module <NUM>.

As mentioned, the housing assembly <NUM> may support the shaft <NUM> and the rotor <NUM> for rotation about the axis <NUM>. For example, as shown in <FIG>, the e-charger <NUM> may include a first bearing <NUM> and a second bearing <NUM>. The first bearing <NUM> may be disposed in the central opening <NUM> of the second member <NUM> and may include an outer race that is fixed to the second member <NUM>, an inner race that is fixed to the intermediate segment <NUM> of the shaft <NUM>, and a plurality of ball bearings disposed between the inner and outer races. The second bearing <NUM> may be similar, except it may be disposed in the central opening <NUM> of the third member <NUM>, with its outer race fixed to the third member <NUM> and its inner race fixed to the intermediate segment <NUM> of the shaft <NUM>.

In some embodiments, the first bearing <NUM> and/or the second bearing <NUM> may be greasepack ball bearings. These bearings may provide cost savings in some embodiments. Also, these types of bearings can be packaged within relatively compact spaces within the e-charger.

Furthermore, the e-charger <NUM> may include at least one coolant flowpath therethrough. For example, as shown in <FIG>, the e-charger <NUM> may include a port <NUM>, a front groove <NUM>, and a rear groove <NUM>. The port <NUM> may extend through the outer shell member <NUM> and allow coolant flow into or out of the e-charger <NUM>. The front groove <NUM> may extend radially into the second member <NUM>, separating the first and second outer portions <NUM>, <NUM> of the second member <NUM>. The rear groove <NUM> may extend radially into the third member <NUM>, separating the first and second outer portions <NUM>, <NUM>. Accordingly, coolant may flow between the port <NUM>, the front groove <NUM>, and the rear groove <NUM> to provide a cooling effect for the e-charger <NUM>.

Additionally, the e-charger <NUM> may include a number of seals, such as O-rings <NUM>. The O-rings <NUM> may be conventional and may be provided between different members of the housing assembly <NUM> to prevent leakage of the coolant, to prevent intrusion of foreign materials, and/or to otherwise provide a seal between different members of the e-charger <NUM>.

As shown in <FIG>, <FIG>, and <FIG>, the e-charger <NUM> may also include a damping system <NUM>. The damping system <NUM> may include a first dampener <NUM> and a second dampener <NUM> in some embodiments. The first dampener <NUM> and the second dampener <NUM> may be substantially similar to each other except as noted below.

The first dampener <NUM> may be substantially annular. As shown in <FIG>, the first dampener <NUM> may be a unitary (i.e., one-piece) member that extends annularly and continuously about the axis <NUM> of rotation As shown in <FIG> and <FIG>, the first dampener <NUM> may include an inner radial surface <NUM> and an outer radial surface <NUM>. The first dampener <NUM> may further include an outer edge <NUM> and an inner edge <NUM>.

In some embodiments, the inner radial surface <NUM> and/or the outer radial surface <NUM> may be uneven. For example, the inner radial surface <NUM> and the outer radial surface <NUM> may be wavy, bumpy, and/or corrugated in some embodiments. As such, the inner radial surface <NUM> may have alternating peaks and troughs as shown in <FIG>. The outer radial surface <NUM> may similarly include alternating peaks and troughs. The peaks and troughs of the inner radial surface <NUM> may be inverse to those of the peaks and troughs of the outer radial surface <NUM>. Also, in some embodiments, a thickness of the dampener <NUM> (measured between the inner radial surface <NUM> and the outer radial surface <NUM>) may be substantially constant and continuous in the circumferential direction about the axis <NUM>.

The first dampener <NUM> may be made out of a metallic material in some embodiments. Also, the first dampener <NUM> may be resilient and flexible. As such, the dampener <NUM> may elastically deform (e.g., between a neutral first position shown in the Figures and a second deformed position). In some embodiments, the inner radial surface <NUM> and/or the outer radial surface <NUM> may deform when the first dampener <NUM> is subjected to sufficient force. For example, the waves, bumps, and/or corrugations may elastically deflect when the first dampener <NUM> is under a sufficient load.

The first dampener <NUM> may be disposed between the first member <NUM> and the second member <NUM> of the housing assembly <NUM>. More specifically, as shown in <FIG>, portions of the inner radial surface <NUM> of the first dampener <NUM> may abut against an opposing outer diameter surface <NUM> of the second outer portion <NUM> of the second member <NUM>. Also, portions of the outer radial surface <NUM> may abut against the opposing inner diameter surface <NUM> of the first end <NUM> of the first member <NUM>. Furthermore, as shown in <FIG>, the outer edge <NUM> may abut against an opposing shoulder <NUM> of the second outer portion <NUM>. Additionally, the inner edge <NUM> may abut against the opposing front vertical face <NUM> of the first member <NUM> of the housing assembly <NUM>.

Accordingly, the first dampener <NUM> may provide dampening of forces (e.g., vibrational and other forces) that transfer between the first member <NUM> and the second member <NUM> of the housing assembly <NUM>. The first dampener <NUM> may resiliently deflect in order to dampen and reduce these forces. Also, in some embodiments, the first dampener <NUM> may provide dampening to forces that are directed radially and/or axially with respect to the axis <NUM>.

The second dampener <NUM> may be substantially similar to the first dampener <NUM> except that the second dampener <NUM> may be disposed between the first member <NUM> and the third member <NUM>. Specifically, as shown in <FIG>, the second dampener <NUM> may abut radially against the second outer portion <NUM> of the third member <NUM> and the second end <NUM> of the first member <NUM>. Also, the second dampener <NUM> may abut axially against the first member <NUM> and the third member <NUM>. Accordingly, the second dampener <NUM> may provide dampening to radial and/or axial forces that transfer between the first member <NUM> and the third member <NUM>.

Accordingly, the damping system <NUM> of the present disclosure may reduce radial and axial loads of the e-charger <NUM>. The damping system <NUM> may also increase the operating life of the e-charger, for example, because loading on the bearings <NUM>, <NUM> may be reduced. Also, since the loads are reduced, the bearings <NUM>, <NUM> included in the e-charger <NUM> may be relatively cost-effective and compact bearings, such as greasepack ball bearings. Furthermore, the dampeners <NUM>, <NUM> may compensate for any bearing misalignment. Also, the dampeners <NUM>, <NUM> may decrease vibration of the stator <NUM>. The temperature of the damping system <NUM> may be controlled, for example, by the coolant flowing within the nearby coolant grooves <NUM>, <NUM>. In addition, the damping system <NUM> may allow the e-charger <NUM> to be more compact than conventional e-chargers. Moreover, the damping system <NUM> may provide increased manufacturing efficiency. For example, the dampeners <NUM>, <NUM> may be relatively simple to assemble within the housing assembly <NUM>. Thus, the e-charger <NUM> may be manufactured and assembled in an efficient manner.

Claim 1:
An electrically driven compressor assembly (<NUM>) comprising:
a shaft (<NUM>);
a compressor wheel (<NUM>) that is supported on the shaft (<NUM>);
an electric motor (<NUM>) with a stator (<NUM>) and a rotor (<NUM>), the electric motor (<NUM>) configured to rotate the shaft (<NUM>) and the compressor wheel (<NUM>);
a housing assembly (<NUM>) configured to house the stator (<NUM>), the rotor (<NUM>), and at least part of the shaft (<NUM>), the housing assembly (<NUM>) including a first member (<NUM>) and a second member (<NUM>), the second member (<NUM>) being radially overlapped and received within an open first end (<NUM>) of the first member (<NUM>) of the housing assembly (<NUM>);
a bearing (<NUM>) configured to support rotation of the shaft (<NUM>) relative to the second member (<NUM>) of the housing assembly (<NUM>) about an axis of rotation (<NUM>); characterized in that
a dampener (<NUM>) is disposed between the first member (<NUM>) and the second member (<NUM>) of the housing assembly (<NUM>), the dampener (<NUM>) configured to elastically deform to provide dampening of a force transferred between the first member (<NUM>) and the second member (<NUM>) of the housing assembly (<NUM>).