WO2014209870A1

WO2014209870A1 - Supercharger for a combustion engine

Info

Publication number: WO2014209870A1
Application number: PCT/US2014/043631
Authority: WO
Inventors: Robert Keefover
Original assignee: Borgwarner Inc.
Priority date: 2013-06-28
Filing date: 2014-06-23
Publication date: 2014-12-31
Also published as: GB201601095D0; GB2531212B; GB2531212A

Abstract

The invention describes a supercharger (20) for a combustion engine (21) comprising an electric driven radial compressor (1) having a compressor housing (2) within which a compressor wheel (3) is disposed that is fixed to one end (4) of a rotor shaft (5), and that comprises a backplate (6) disposed adjacent to the back (32) of the compressor wheel (3) and fixed to the compressor housing (2); a brushless electric motor (7) that is fixed to the compressor housing (2); a power electronics circuit board (9), wherein the power electronics circuit board (9) is placed on the backplate (6).

Description

SUPERCHARGER FOR A COMBUSTION ENGINE

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and all benefits of U.S. Provisional Application No.

61/840,663, filed on June 28, 2013, and entitled "Supercharger For A Combustion Engine."

BACKGROUND

1. Field of the Invention

The invention concerns a supercharger for a combustion that includes an electric motor fixed to the compressor housing.

2. Description of Related Art

A supercharger includes electronic components that are placed at an axial end of the compressor or on a flat surface at the stator housing. It is, therefore, an object underlying the present invention to provide an electric driven radially compressor that enables a compact configuration.

SUMMARY

In some aspects, a supercharger for a combustion engine includes an electric driven radial compressor having a compressor housing. A compressor wheel is disposed within the compressor housing and is fixed to one end of a rotor shaft. The compressor housing includes a backplate disposed adjacent to the back of the compressor wheel and fixed to the compressor housing. The supercharger also includes a brushless electric motor that is fixed to the compressor housing; and a power electronics circuit board. In the supercharger, the power electronics circuit board is placed on the backplate. By placing the power electronics circuit board on the backplate of the compressor housing it is achieved that the compressor according to the present invention can be reduced in size compared to known designs.

The supercharger may include one or more of the following features. The backplate comprises a cooling jacket. A magnet is disposed on the rotor shaft. A stator surrounds the magnet. A stator housing surrounds the stator. A dirt protection cover is disposed at the backplate. Electronic components are disposed within the dirt protection cover. The power electronics circuit board is disposed coaxially to the rotor shaft. The backplate comprises a recess the depth and inner contour of which corresponds to the thickness and outer contour of the power electronics circuit board. The electric motor is a brushless DC motor. The combustion engine is an internal combustion engine or a fuel cell. The power electronics circuit board has a circular outer contour that is provided with a recess for intake and outlet conduits of the cooling jacket.

In one embodiment, the power electronics circuit board can be disposed in a recess of the backplate the depth and inner contour of which is adapted to the thickness and outer contour of the circuit board.

Moreover, alternatively it is also possible that the electronics circuit board can be completely integrated into the backplate, e.g. by a molding process.

Moreover, in another embodiment, the power electronics circuit board can be disposed close to a cooling jacket of the backplate so that the power electronics circuit board can effectively be cooled during operation.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details, features and advantages of the present invention can be gathered from the following description of the drawings in which:

Fig. 1 is a somewhat simplified cross section of a first embodiment of the supercharger according to the present invention,

Fig. 2 is a perspective view onto the backplate of the compressor housing with an electric motor of the compressor removed for a better depiction of the disposition of a power electronics circuit board in a backplate of the compressor housing,

Fig. 3 is a somewhat simplified cross section view according to claim 1 of a second embodiment of the supercharger according to the present invention, and

Fig. 4 is a simplified schematic view of a combustion engine, preferably an internal combustion engine as a fuel or diesel engine, being equipped with the supercharger according to the first or second embodiment. DETAILED DESCRIPTION

Referring to Figs. 1 and 2, the supercharger 20 includes a compressor 1. The compressor 1 has a compressor housing 2 within which the compressor wheel 3 is disposed. The compressor wheel 3 is fixed on one end 4 of a rotor shaft 5. Moreover, the compressor housing 2 comprises a backplate 6 disposed along the back 32 of the compressor wheel 3. The compressor 1 also includes an electric motor 7 having a motor shaft 8 that is connected to the rotor shaft 5. The motor shaft 8 and the rotor shaft 5 are advantageously formed as a unitary component or may also constitute separate components that are suitably fixed to one another. The electric motor 7 includes a stator housing 13 within which the shaft arrangement of the rotor shaft 5 and motor shaft 8 is journaled by means of bearings 16 and 17. The rotor shaft 5 is provided with a magnet 11 that is surrounded by an outer stator coil 12. Moreover, the electric motor 7 comprises a power electronics circuit board 9 that is integrated in the backplate 6 of the compressor housing 5. As can be gathered from Figs. 1 and 2, the backplate 6 comprises a recess 18 into which the circuit board 9 can be disposed so that a flush arrangement can be achieved. For this purpose the recess 18 has a depth D (see Fig. 1) and an inner contour 12 (see Fig. 2) that corresponds to the thickness of the circuit board 9 and the outer contour thereof. In addition, the power electronics circuit board 9 may be disposed coaxially with the rotor shaft 5. As an alternative to the embodiment shown in Figs. 1 and 2, it may also be possible to fully integrate the circuit board 9 within the backplate 6.

As can be seen from Fig. 1, the backplate 6 comprises a cooling jacket 10 that is disposed in close proximity to circuit board 9 so that its cooling during operation can be enhanced. For example, the cooling jacket 10 may include fluid passageways through which cooling fluid may be passed.

Moreover, the embodiment of Fig. 1 comprises a dirt protection cover 14 which surrounds at least a portion of the power electronics circuit board 9, and within which further electronic components 15 of the circuit board 9 can be located. The dirt protection cover 14 serves the purpose of protecting the circuit board 9 and the electronic components 15 from being polluted.

Referring to Fig. 3, a second embodiment of the supercharger 20 includes features common to the first embodiment described above with respect to Figs. 1 and 2, and the features that correspond to the first embodiment have been identified with the same reference numerals. The second embodiment according to Fig. 3 differs from the first embodiment by the disposition of the electronic circuit board 9 on a rear surface 31 of the backplate 6, rather than within the backplate 6. As can be seen from Fig. 3, the disposition of the electronic circuit board 9 according to Fig. 3 provides a small clearance 19 between the circuit board 9 and the rear surface 31 of the backplate 6.

As another possible alternative it is to be mentioned that the circuit board 9 could also be directly placed on the rear surface 31 of the backplate 6. In this case, the circuit board 9 could be fixed to the back surface 31 e. g. by an appropriate adhesive.

Both embodiments according to Figs. 1 and 3 show that the backplate 6 is disposed behind the compressor wheel 3 thereby closing the compressor housing 2. The backplate 6 can be fixed to the compressor housing 2 by suitable fixing means as e. g. a screw arrangement.

The circuit board 9 of both the first and the second embodiment according to Figs. 1 and 3, respectively, may comprise all necessary electronic features to fulfill the function of a commutator, for example including a suitable control circuit with power transistors or power MOSFETs as well as sensors, in particular hall sensors. In addition, or alternatively, the circuit board 9 may comprise all necessary electronic features for complete power electronics for driving an electric motor, for example a brushless DC motor.

The electronic components 15 may include, for example, a capacitor. Referring to Figure 4, a combustion engine 21 is equipped with a supercharger 20 according to either the first or the second embodiment. The combustion engine 21 may take the form of an internal combustion engine as e. g. a diesel or a fuel engine. The combustion engine 21 includes an intake conduit 22 in which the compressor 1 of supercharger 20 is disposed and is driven by electric motor 7.

Downstream of the compressor 21, there may be disposed a charged air cooler 23. Downstream of the cooler 23, there may be disposed a throttle 24 in conduit 22. The conduit 22 guides the compressed air represented by arrow CA to an intake manifold 25 of the combustion engine 21. As can be seen from Fig. 4, the combustion engine 21 furthermore comprises an exhaust gas manifold 26 that guides exhaust gas represented by arrow EG into an exhaust gas conduit 27. The embodiment shown in Fig. 4, moreover, comprises an exhaust gas recirculation (EGR) line 28 within which an EGR cooler 29 and an EGR valve 30 are disposed. Such an EGR line 28 is, however, not mandatory but constitutes an optional equipment of engine 21.

So, upon driving the electric motor 7, the compressor 1 compresses fresh air flowing into the compressor from intake conduit 22 and supplies compressed air CA through cooler 28 and the throttle 24 to the intake manifold 25 of the combustion engine 21. In addition to the written disclosure of the invention, reference is explicitly made to Figs. 1 and 4 for the purpose of completing the disclosure of the present invention.

Aspects described herein can be embodied in other forms and combinations without departing from the spirit or essential attributes thereof. Thus, it will of course be understood that embodiments are not limited to the specific details described herein, which are given by way of example only, and that various modifications and alterations are possible within the scope of the following claims.

List of reference signs

1 compressor

2 compressor housing

3 compressor wheel

4 end

5 rotor shaft

6 backplate

7 electric motor

8 shaft

9 power electronics circuit board

10 cooling jacket

11 magnet

12 stator coil

13 stator housing

14 dirt protection cover

15 electronic components

16, 17 bearings

18 recess

19 clearance

20 supercharger

21 combustion engine

22 intake conduit

23 charged air cooler

24 throttle

25 intake manifold

26 exhaust gas manifold

27 exhaust gas conduit

28 EGR line

29 EGR cooler

30 EGR valve

31 rear surface

32 back of compressor wheel 3

33 outer contour recess

intake and outlet conduits

Claims

What is claimed is:

1. A supercharger (20) for a combustion engine (21) comprising:

an electrically-driven radial compressor (1) having a compressor housing (2) within which a compressor wheel (3) is disposed that is fixed to one end (4) of a rotor shaft (5), and

that comprises a backplate (6) disposed adjacent to a back (32) of the compressor wheel (3) and fixed to the compressor housing (2);

a brushless electric motor (7)

that is fixed to the compressor housing (2); and

- a power electronics circuit board (9),

wherein the power electronics circuit board (9) is placed on the backplate (6).

2. The supercharger (20) according to claim 1, wherein the backplate (6) comprises a cooling jacket (10).

3. The supercharger (20) according to claim 1 or 2, wherein a magnet (11) is disposed on the rotor shaft (5).

4. The supercharger (20) according to claim 3, wherein a stator (12) surrounds the magnet (11).

5. The supercharger (20) according to claim 3 or 4, wherein a stator housing (13) surrounds the stator (12).

6. The supercharger (20) according to one of claims 1 to 5, wherein a dirt protection cover (14) is disposed at the backplate (6).

7. The supercharger (20) according to claim 6, wherein electronic components (15) are disposed within the dirt protection cover (14).

8. The supercharger (20) according to one of claims 1 to 7, wherein the power electronics circuit board (9) is disposed coaxially with the rotor shaft (5).

9. The supercharger (20) according to one of claims 1 to 8, wherein the backplate (6) comprises a recess (18) the depth (D) and inner contour of which corresponds to the thickness and outer contour of the power electronics circuit board (9).

10. The supercharger (20) according to one of claims 1 to 9, wherein the electric motor (7) is a brushless DC motor.

11. The supercharger (20) according to one of claims 1 to 10, wherein the combustion engine is an internal combustion engine or a fuel cell.

12. The supercharger (20) according to one of claims 2 to 11 wherein the power electronics circuit board (9) has a circular outer contour (33) that is provided with a recess (34) for intake and outlet conduits (35, 36) of the cooling jacket (10).