Charging apparatus for a combustion engine

Abstract

A charging apparatus (20) for a combustion engine, having a compressor (1) which has a compressor housing (2) in which a compressor wheel (3) is arranged, the compressor wheel being mounted on one end (4) of a rotor shaft (5), and which has a compressor housing rear wall (6); and having an electric motor (7) which has a stator winding (12) which surrounds a magnet (11), which is arranged on the rotor shaft (5), on the outside. The stator winding (12) is an iron-free stator winding, and the electric motor (7) is a brushless DC motor.

Claims

1. A charging apparatus (20) for a combustion engine, comprising: a compressor (1) which has a compressor housing (2) in which a compressor wheel (3) is arranged, said compressor wheel being mounted on one end (4) of a rotor shaft (5), and which compressor housing (2) has a compressor housing rear wall (6) which is adjacent to a compressor wheel rear side (36); and a brushless electric motor (7) which has a rotor including a magnet arranged on the outside of a shaft (8), a stator including a stator winding (12), which surrounds the magnet (11), the stator winding (12) having axial ends having an outer circumference (31) having a diameter, the stator winding (12) having a recess (19) between the axial ends, the recess having an outer surface having a diameter smaller than the outer diameter of the axial ends, wherein the stator winding is self-supporting, and an annular laminated core (18) having a cylindrical inner surface (37), the annular laminated core (18) arranged in the recess (19) of the stator winding (12), the cylindrical inner surface (37) in direct contact with the outer surface of the stator winding recess (19), the outer circumferential surface (32) of the annular laminated core (18) projecting radially beyond the outer circumferential surface (31) of the axial ends of the stator winding (12), and a stator housing (13) which surrounds the stator winding (12) on the outside, wherein: a first bearing (16) is supported in a recess of the compressor housing rear wall (6) and a second bearing (17) is supported in a bearing section of the stator housing (13), the magnet (11) is arranged on the rotor shaft (5) between the first bearing (16) and the second bearing (17), a power electronics circuit (9) arranged between the compressor housing rear wall (6) and the electric motor (7), and the compressor housing rear wall (6) of the compressor housing (2) has a cooling jacket (10).

2. The charging apparatus as claimed in claim 1, comprising a dirt-protection cover (14) arranged on the compressor housing rear wall (6).

3. The charging apparatus as claimed in claim 1, wherein winding taps (34, 35) are provided on an end surface (33) of the stator winding (12).

4. The charging apparatus as claimed in claim 1, wherein the combustion engine is an internal combustion engine.

5. The charging apparatus as claimed in claim 1, wherein the stator winding 12 is in the form of an iron-free winding.

6. A charging apparatus (20) connected to supply compressed air to a fuel cell, comprising a charging apparatus comprising a compressor (1) which has a compressor housing (2) in which a compressor wheel (3) is arranged, said compressor wheel being mounted on one end (4) of a rotor shaft (5), and which compressor housing (2) has a compressor housing rear wall (6) which is adjacent to a compressor wheel rear side (36); and a brushless electric motor (7) which has a rotor including a magnet arranged on the outside of a shaft (8), and a stator including a stator winding (12), which surrounds the magnet (11), the stator winding (12) having axial ends having an outer circumference (31) having a diameter, the stator winding (12) having a recess (19) between the axial ends, the recess having an outer surface having a diameter smaller than the outer diameter of the axial ends, wherein the stator winding is self-supporting, and an annular laminated core (18) having a cylindrical inner surface (37), the annular laminated core (18) arranged in the recess (19) of the stator winding (12), the cylindrical inner surface (37) in direct contact with the outer surface of the stator winding recess (19), the outer circumferential surface (32) of the annular laminated core (18) projecting radially beyond the outer circumferential surface (31) of the axial ends of the stator winding (12); a stator housing (13) which surrounds the stator winding (12) on the outside, wherein: a first bearing (16) is supported in a recess of the compressor housing rear wall (6) and a second bearing (17) is supported in a bearing section of the stator housing (13), the magnet (11) is arranged on the rotor shaft (5) between the first bearing (16) and the second bearing (17), a power electronics circuit (9) arranged between the compressor housing rear wall (6) and the electric motor (7), and the compressor housing rear wall (6) of the compressor housing (2) has a cooling jacket (10) between the compressor wheel and power electronics circuit (9); a fuel cell; and means for connecting the fuel cell to the charging apparatus.

Description

BRIEF DESCRIPTION OF ME SEVERAL VIEWS OF THE DRAWINGS

(1) Further details, advantages and features of the present invention can be gathered from the following description of exemplary embodiments with reference to the drawing, in which:

(2) FIG. 1 is a schematically slightly simplified sectional illustration through a first embodiment of a charging apparatus according to the invention;

(3) FIG. 2 is a perspective illustration of a stator winding according to the invention;

(4) FIG. 3 is a perspective illustration of the stator winding according to FIG. 2 in a sectioned state; and

(5) FIG. 4 is a basic diagram of a combustion engine with a charging apparatus according to the invention, and

(6) FIG. 5 is a schematic diagram of a fuel cell provided with a charging apparatus according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

(7) FIG. 1 shows an embodiment of a charging apparatus 20 comprising an electrically driven compressor 1. The compressor 1 has a compressor housing 2 in which a compressor wheel 3 is arranged. The compressor wheel 3 is mounted on one end 4 of a rotor shaft 5.

(8) As is also illustrated in FIG. 1, the compressor housing 2 has a compressor housing rear wall 6 which is in the form of a compressor housing cover in the illustrated exemplary embodiment.

(9) In this case, the compressor housing rear wall 6 is provided with a cooling jacket 10, preferably for cooling water. As illustrated in FIG. 1, the compressor housing rear wall 6 is arranged behind the compressor wheel and is fixed to the compressor housing 2 and closes said compressor housing in this way.

(10) The compressor 1 also has an electric motor 7. The electric motor 7 comprises a shaft 8 which is connected to a rotor shaft 5. In the illustrated embodiment, the shaft 8 and the rotor shaft 5 are designed as an integral component, as is shown in detail in FIG. 1. In this case, the shaft 8 is in the form of a shaft stub which has a smaller outside diameter than the rotor shaft 5 and on which a bearing 16 is arranged. The end 4 of the rotor shaft 5 is likewise of reduced diameter in relation to the rotor shaft 5 and is fitted with a second bearing 17. As shown in FIG. 1, the bearing 17 is supported against a bearing section of a stator housing 13, whereas the bearing 16 is supported, by way of its outer ring, in a recess of the compressor housing rear wall 6.

(11) A magnet 11 is also provided on the rotor shaft 5, said magnet interacting with a stator winding 12 which surrounds said magnet on the outside.

(12) The embodiment of the compressor 1 according to FIG. 1 also has a dirt-protection cover 14 which is mounted on the stator housing 13 or on the compressor housing rear wall 6 and in which electronics components 15 of a power electronics circuit or electronics printed circuit board 9 are arranged.

(13) As illustrated in FIG. 1, the power electronics circuit 9 is arranged between the compressor housing rear wall 6 and the electric motor 7 or the dirt-protection cover 14. To this end, the power electronics circuit 9 can be firmly clamped, for example, between the dirt-protection cover 14 and the compressor housing rear wall 6, or else mounted, for example fixedly adhesively bonded, on one of the two parts.

(14) This arrangement results in the advantage that the power electronics circuit 9 is arranged adjacent to the cooling jacket 10, this considerably improving the cooling effect of said cooling jacket with respect to the power electronics circuit 9. The power electronics circuit 9 can comprise all of the required components for fulfilling the function of an electronic commutator. Said power electronics circuit is, in particular, a control circuit comprising transistors or so-called MOSFETs. The power electronics circuit 9 can also comprise sensors, in particular Hall sensors. The electronic components 15 comprise, in particular, a capacitor, amongst others.

(15) A thermally conductive paste can be provided between the power electronics circuit 9 and the cooling jacket 10 or the compressor housing rear wall 6 in which the cooling jacket 10 is arranged.

(16) The compressor housing rear wall 6 could also be formed by an end wall of the stator housing 13, in which end wall the bearing 17 would then be arranged. In this embodiment, the stator housing 13 likewise has an inner cooling arrangement and therefore a cooling jacket 10, wherein, in this embodiment too, the power electronics circuit 9 is arranged between the compressor housing rear wall 6 and the electric motor 7 or its stator housing 13, and therefore enjoys the same advantages of a compact construction and improved cooling of the components.

(17) The stator winding 12 according to the invention is illustrated in detail in FIGS. 2 and 3.

(18) The stator winding 12 is in the form of an iron-free winding which is self-supporting and, in the case of the example, forms a hollow cylinder. A laminated core 18 is arranged on the stator winding 12, to which end the stator winding 12 has a recess 19, into which the laminated core 18 is inserted, in the particularly preferred embodiment which is illustrated in FIG. 3. As can be gathered from looking at FIGS. 2 and 3 together, the outer circumferential surface 32 of the laminated core 18 projects radially beyond the outer circumferential surface 31 of the stator winding 12 in this case.

(19) FIGS. 2 and 3 also show that two winding taps 34 and 35 are provided on an end surface 33 of the stator winding 12. The charging apparatus 20 which was explained above with reference to FIGS. 1 to 3 is suitable, in particular, for combustion engines, such as internal combustion engines as shown in FIG. 4, or fuel cells as shown in FIG. 5.

(20) FIG. 4 is a schematically highly simplified illustration of a combustion engine 21, for example in the form of a (diesel or petrol) internal combustion engine. The combustion engine 21 has an intake line 22 in which the compressor 1 of the charging apparatus 20 is arranged, said compressor being driven by the electric motor 7. A charge air cooler 23, followed by a throttle 24, can be arranged downstream of the compressor 1 in the intake line 22. The compressed air, which is symbolized by the arrow CA, from the compressor 1 is supplied to an intake manifold 25, and the cylinders of the combustion engine 21 are supplied with the compressed air from said intake manifold.

(21) The exhaust gas EG is supplied to an exhaust gas line 27 via an exhaust gas manifold 26.

(22) In the particularly preferred embodiment which is illustrated in FIG. 4, the internal combustion engine 21 is also provided with an exhaust gas return line 28 in which an exhaust gas cooler 29 and a valve 23 are arranged. However, said exhaust gas return line 28, together with its components 29 and 30, is not mandatory, but rather constitutes merely a particularly preferred embodiment.

(23) In addition to the above written description of the invention, reference is hereby explicitly made, for additional disclosure thereof, to the diagrammatic illustration of the invention in FIGS. 1 to 4.

LIST OF REFERENCE SYMBOLS

(24) 1 Compressor 2 Compressor housing 3 Compressor wheel 4 End 5 Rotor shaft 6 Compressor housing rear wall 7 Electric motor, in particular a brushless DC motor 8 Shaft 9 Power electronics circuit/electronics printed circuit board 10 Cooling jacket 11 Magnet 12 Stator winding 13 Stator housing 14 Dirt-protection cover 15 Electronics components 16, 17 Bearings 18 Laminated core 19 Recess 20 Charging apparatus 21 Combustion engine 22 Intake line 23 Charge air cooler 24 Throttle 25 Intake manifold 26 Exhaust gas manifold 27 Exhaust gas line 28 Exhaust gas return line 29 Exhaust gas cooler 30 Valve 31, 32 Outer circumferential surface 33 End surface 34, 35 Winding taps 36 Compressor wheel rear side 37 Inner surface CA Compressed air EG Exhaust gas