阅读说明：本技术 包含冷却装置的铁路电动马达以及相关联的铁路车辆 (Railway electric motor comprising a cooling device and associated railway vehicle ) 是由 安德里-马米·兰德里亚 菲利普·迪布瓦 于 2019-07-26 设计创作，主要内容包括：本发明涉及一种电动马达(22),其包含转子(32)、定子(34)、冷却装置(36)和框架(30),所述框架(30)包含冷却孔(50、52),所述冷却装置(36)包含冷却元件(60、62),所述冷却元件(60、62)包含紧固到所述转子(32)的紧固壁(64、66)和冷却壁(74、76),所述冷却壁(74、76)包含能够与穿过所述冷却孔(50、52)的气流接触的内表面(74A、76A)和在所述定子(34)对面的外表面(74B、76B)。根据本发明,所述内表面(74A、76A)和所述外表面(74B、76B)是总体上平滑的并且没有突出元件。(The invention relates to an electric motor (22) comprising a rotor (32), a stator (34), a cooling device (36) and a frame (30), the frame (30) comprising cooling holes (50, 52), the cooling device (36) comprising a cooling element (60, 62), the cooling element (60, 62) comprising a fastening wall (64, 66) fastened to the rotor (32) and a cooling wall (74, 76), the cooling wall (74, 76) comprising an inner surface (74A, 76A) capable of being in contact with an air flow passing through the cooling holes (50, 52) and an outer surface (74B, 76B) opposite the stator (34). According to the invention, the inner surface (74A, 76A) and the outer surface (74B, 76B) are generally smooth and free of protruding elements.)

1. An electric motor (22) comprising a rotor (32), a stator (34), a cooling device (36) and a frame (30),

the frame (30) defining an inner space (E1) for receiving the rotor (32), the stator (34) and the cooling device (36), the frame (30) comprising at least one cooling hole (50, 52) connecting the inner space (E1) to an outer space (E2) of the frame (30),

the rotor (32) comprising two opposite ends (32A, 32B) along the axis of rotation (R) of the rotor (32),

the cooling device (36) comprises at least one cooling element (60, 62) positioned at one of the ends (32A, 32B) of the rotor (32), each cooling element (60, 62) comprising a fastening wall (64, 66) fastened to the rotor (32) and a cooling wall (74, 76), the fastening wall (64, 66) being rotationally fixed with the rotor (32), the cooling wall (74, 76) extending along the rotation axis (R) of the rotor (32) from the fastening wall (64, 66) to a free end (70, 72) of the cooling element (60, 62), the cooling wall (74, 76) defining an inner volume around which it surrounds and comprising an inner surface (74A, 76A) and an outer surface (74B, 76B), the inner surface (74A, 76A) being opposite and capable of passing through the cooling hole (50, 52), 52) Opposite the stator (34) and opposite the inner surface (74A, 76A), the inner and outer surfaces extending from the fastening wall (64, 66) to the free end (70, 72),

characterized in that said inner surface (74A, 76A) and said outer surface (74B, 76B) are generally smooth and free of protruding elements.

2. The electric motor according to claim 1, wherein each cooling hole (50, 52) is arranged such that, for each cooling hole (50, 52), air passing through the inner space (E1) via the cooling hole (50, 52) during the rotation of the rotor (32) exits through the same cooling hole (50, 52).

3. The electric motor according to claim 1 or 2, wherein the inner (74A, 76A) and outer (74B, 76B) surfaces are generally smooth adjustment surfaces without protruding elements, and advantageously in the form of a conical or cylindrical body extending along the rotation axis (R) of the rotor (32).

4. The electric motor according to any one of the preceding claims, wherein each cooling hole (50, 52) opens in the inner space (E1) near the inner surface (74A, 76A) of one or more cooling walls (74, 76) and at a distance of less than 5mm measured along the central axis of the cooling hole (50, 52).

5. The electric motor according to any one of the preceding claims, wherein the cooling arrangement (36) comprises two cooling elements (60, 62), each being positioned at one respective end (32A, 32B) of the rotor (32), and wherein the frame (30) comprises at least one respective cooling hole (50, 52) for each cooling element (60, 62).

6. The electric motor according to any of the preceding claims, wherein the electric motor (22) is configured to reach a nominal speed of more than 5000 rpm, preferably about 6000 rpm.

7. An electric motor according to any preceding claim, wherein each cooling hole (50, 52) has a cross-section in a direction perpendicular to an axis through the hole of 12.56cm ²And 3.14cm ²Preferably 27cm ²And 78cm ²The surface area in between.

8. The electric motor according to any one of the preceding claims, wherein each cooling wall (74, 76) divides the internal space (E1) into a primary space (80A, 82A) and a secondary space (80B, 82B), the primary space (80A, 82A) for receiving outside air, being connected ventilably to a plurality or one of the cooling holes (50, 52), and the air contained by the primary space (80A, 82A) being in contact with the internal surface (74A, 76A), the air contained by the secondary space (80B, 82B) being in contact with the external surface (74B, 76B) and the stator (34).

9. Electric motor according to any one of the preceding claims, wherein each free extremity (70, 72) is positioned opposite a respective lateral wall (40, 42) of the frame (30), the lateral walls (40, 42) being provided with an inner portion (77, 78) extending along the rotation axis (R) of the rotor (32) and surrounding the free extremity (70, 72), the radial distance between the free extremity (70, 72) and the inner portion (77, 78) being less than 5mm, preferably less than 1 mm.

10. A rail vehicle (10) comprising at least one electric motor (22), characterized in that the or each electric motor (22) is an electric motor according to any one of the preceding claims.

Technical Field

The present invention relates to an electric motor comprising a cooling device and a rail vehicle comprising such an electric motor.

Background

In the field of electric motors, in particular for railway vehicles, it is known to use cooling devices that circulate an external fluid (for example air) outside the motor, in order to cool the rotor and/or the stator of the motor.

In particular, known from document JP5801127B2 is an electric motor provided with a cooling device comprising cooling elements positioned on each side of the rotor and capable of rotating simultaneously with the rotor. Each cooling element is capable of circulating an air flow from an external air inlet aperture towards an air outlet aperture when it is rotating, by passing through an air passage in contact with the cooling element. However, this motor has a complex structure, is noisy when it is running and the rotor is rotating, and is not optimized in terms of efficiency, with mechanical losses being significant.

Disclosure of Invention

The present invention aims to solve these drawbacks by proposing an electric motor with a simplified structure, in which noise and mechanical losses are minimized while ensuring cooling of the motor.

To this end, the invention relates to an electric motor comprising a rotor, a stator, a cooling device and a frame,

the frame defining an interior space for receiving the rotor, the stator and the cooling device, the frame including at least one cooling hole connecting the interior space to an exterior space of the frame,

the rotor comprises two opposite ends along the rotational axis of the rotor,

the cooling device comprising at least one cooling element positioned at one of the ends of the rotor, each cooling element comprising a fastening wall fastened to the rotor and a cooling wall rotationally fixed with the rotor, the cooling wall extending along the rotational axis of the rotor from the fastening wall to a free end of the cooling element, the cooling wall defining an inner volume around which it surrounds and comprising an inner surface opposite a plurality or one of the cooling holes and contactable with an air flow passing through the cooling hole and an outer surface opposite the inner surface opposite the stator, the inner and outer surfaces extending from the fastening wall to the free end,

wherein the inner surface and the outer surface are generally smooth and free of protruding elements.

Thanks to the invention, the structure of the electric motor is simplified and noise and mechanical losses are minimized, since each cooling element has a simplified structure and no protruding elements at its cooling walls. The structure of the inner and outer surfaces of each stave cooler, which is a generally smooth surface, allows for a simplified construction of the cooling device and can limit mechanical losses due to friction and noise caused by such friction.

According to particular embodiments, the invention has one or more of the following features, considered alone or according to any technically possible combination:

-each cooling hole is arranged such that, for each cooling hole, air passing through the inner space via the cooling hole during the rotation of the rotor exits through the same cooling hole;

-said inner and outer surfaces are generally smooth adjustment surfaces without protruding elements, and advantageously in the form of a conical or cylindrical body (trunk) extending along the rotation axis of the rotor;

-each cooling hole opens in the inner space near the inner surface of one or more cooling walls at a distance measured along the central axis of the cooling hole of less than 5 mm;

-the cooling device comprises two cooling elements, each being positioned at one of the respective ends of the rotor, and wherein the frame comprises at least one respective cooling hole for each cooling element;

-the electric motor is configured to reach a nominal speed greater than 5000 rpm, preferably about 6000 rpm;

each ofThe cooling holes have a cross-section in a direction perpendicular to an axis passing through the holes of 12.56cm ²And 3.14cm ²Preferably 27cm ²And 78cm ²Surface area in between;

-each cooling wall divides the inner space into a primary space for receiving outside air, which is connected in an air-permeable manner to one or more cooling holes and which contains air in contact with the inner surface, and a secondary space which contains air in contact with the outer surface and the stator;

-each free extremity is positioned opposite a respective side wall of the frame, the side wall being provided with an inner portion extending along the rotation axis of the rotor and surrounding the free extremity, the radial distance between the free extremity and the inner portion being less than 5mm, preferably less than 1 mm.

The invention also relates to a rail vehicle comprising at least one electric motor, wherein the or each electric motor is as described above.

Drawings

The invention will be better understood on reading the following description, provided by way of example only and made with reference to the accompanying drawings, in which:

figure 1 is a partially schematic illustration of a railway vehicle comprising two bogies each equipped with an electric motor according to one embodiment of the invention;

figure 2 is a cross-sectional view in a first plane of a portion of the electric motor of figure 1, said first plane being defined by a first direction X-X ' corresponding to the axis of rotation of the rotor of the motor and by a second direction Y-Y ' perpendicular to the first direction X-X '; and

fig. 3 is a side view along the first direction X-X' of the electric motor of fig. 1.

Detailed Description

Fig. 1 shows a rail vehicle 10 which contains a plurality of cars and in particular at least two cars 12, 14 which can be seen in fig. 1.

In fig. 1, the car 12 is a lead car and the car 14 is a trailer.

The car 12 is carried by a first dedicated bogie 16 and a second bogie 18, the second bogie 18 carrying both the car 12 and the car 14.

In the example of fig. 1, each bogie 16, 18 contains two axles 20 and an electric motor 22 capable of rotating one or both axles 20 of the bogie 16, 18.

In a variant, not all bogies are motorized, and only some bogies 16, 18 of the rail vehicle 10 contain electric motors 22.

In fig. 2, for reasons of simplicity, only one half of the electric motor 22 is shown, the other half being substantially symmetrical to the half shown with respect to the direction X-X'.

The electric motor 22 is configured to reach a nominal speed greater than 5000 rpm, preferably about 6000 rpm.

Nominal speed refers to the normal operating speed of the rail vehicle 10 as it travels between two stations at cruising speed.

The electric motor 22 includes a frame 30 or housing of the motor 22 defining an interior space E1, as well as a rotor 32, a stator 34, and a cooling device 36 housed in the interior space E1.

The frame 30 comprises two opposite side walls 40, 42 extending generally perpendicular to the direction X-X 'corresponding to the rotation axis R of the rotor 32, and two opposite longitudinal walls, only one longitudinal wall 44 being shown in fig. 2, extending generally parallel to the axis X-X'. Only the side wall 40 is visible in fig. 3.

The side walls 40, 42 and the longitudinal wall 44 define an interior space E1.

As illustrated by fig. 2 and 3, each side wall 40, 42 contains a cooling hole 50, 52 connecting the inner space E1 to the outer space E2 of the frame 30. Preferably, each lateral wall 40, 42 contains at least two cooling holes 50, 52, said holes 50, 52 being advantageously positioned symmetrically along the rotation axis R.

In the example illustrated by fig. 2 and 3, each sidewall 40, 42 contains eight cooling holes 50, 52, the holes 50, 52 being symmetrically positioned along the rotational axis R of the rotor 32.

The rotor 32 is mounted for rotation on a rotary shaft 54 and is mounted for rotation relative to the stator 34 about a rotational axis R.

The rotor 32 defines two opposite ends 32A, 32B along the rotational axis R of the rotor 32.

The stator 34 surrounds the rotor 32 parallel to the rotation axis R inside the frame 30 and is coaxial with the rotor 32. In general, the rotor 32 and the stator 34 make it possible to convert electrical energy into mechanical energy which is delivered by the shaft 54 of the rotor 32 and intended to drive the axle 20.

The cooling device 36 includes at least one cooling element 60 positioned at one of the ends 32A, 32B of the rotor 32.

Advantageously, and as shown in fig. 2, the cooling device comprises two cooling elements 60, 62, each positioned at one of the respective ends 32A, 32B of the rotor 32.

Also advantageously, the number of cooling holes 50, 52 is a multiple of the number of cooling elements 60, 62, and the frame 30 in particular contains two cooling holes 50, 52 which may or may not be symmetrically positioned along the rotation axis R for each cooling element 60, 62.

In a variant, the frame 30 comprises at least one respective cooling hole 50, 52 for each cooling element 60, 62.

Each cooling element 60, 62 comprises a fastening wall 64, 66 fastened to the rotor 32 and in particular for fastening to the corresponding end 32A, 32B of the rotor 32.

Each fastening wall 64, 66 is rotationally fixed to the rotor 32 and extends in a radial direction with respect to the rotation axis R.

Each fastening wall 64, 66 comprises, along a radial direction with respect to the rotation axis R of the rotor 32, a radial extremity 68, 69, said radial extremity 68, 69 being flush with respect to the rotor 32 along said radial direction. The radial extremities 68, 69 are positioned opposite the stator 34 and in the vicinity of the stator 34, i.e. for example at a distance of less than 5mm, preferably less than 1mm, measured in the radial direction. Each cooling element 60, 62 also includes a free end 70, 72 located opposite the rotor 32 along the rotational axis R of the rotor 32.

Each cooling element 60, 62 further comprises a cooling wall 74, 76 extending along the rotation axis R of the rotor 32 from the fastening wall 64, 66 up to the free end 70, 72 of the cooling element.

Each free end 70, 72 is positioned opposite one of the side walls 40, 42 of the frame. Each side wall 40, 42 is provided with an inner portion 77, 78 extending along the rotation axis R of the rotor 32 and surrounding the respective free end 70, 72, the inner portions 77, 78 being advantageously cylindrical. The inner portions encircle the respective free ends generally parallel to the axis of rotation R of the rotor 32. The radial distance between each free end 70, 72 on the respective inner portion 77, 78 is less than 5mm, preferably 1 mm.

Each stave 74, 76 defines an internal volume around which it surrounds. Each stave surrounds the internal volume it defines while being generally centered on the rotational axis R of the rotor 32.

Defining the internal volume refers to the fact that the cooling walls 74, 76 are closed on themselves and have, for example, a conical or cylindrical body shape.

Each cooling wall 74, 76 comprises an inner surface 74A, 76A opposite a plurality or one of the cooling holes 50, 52 and in particular opposite each cooling hole 50, 52 with which the cooling element to which it belongs is associated. Each cooling wall 74, 76 is capable of being in contact with the airflow through each cooling hole 50, 52 with which it belongs to the cooling element associated.

Each stave 74, 76 also comprises an outer surface 74B, 76B opposite the inner surface 74A, 76A opposite the stator 34.

The inner surfaces 74A, 76A and the outer surfaces 74B, 76B extend from the fastening walls 64, 66 to the free ends 70, 72.

Each cooling wall 74, 76 divides the inner space E1 into a respective main space 80A, 82A and a respective secondary space 80B, 82B, said respective main space 80A, 82A being intended to receive outside air, being connected in a ventilated manner to the or one of the cooling holes 50, 52.

The air contained in each primary space 80A, 82A is in contact with the corresponding inner surface 74A, 76A, and the air contained in each secondary space 80B, 82B is in contact with the corresponding outer surface 74B, 76B and the stator 34.

In other words, each stave generally isolates the air present in the primary spaces 80A, 82A from the air present in the secondary spaces 80B, 82B.

Each cooling hole 50, 52 is arranged such that, for each cooling hole 50, 52, during rotation of the rotor 32, air passing through the inner space E1, and in particular the corresponding main space 80A, 82A, via said cooling hole 50, 52, exits through the same cooling hole 50, 52.

More generally, the cooling walls 74, 76 and cooling holes 50, 52 are arranged and sized to provide the aforementioned operation.

For this purpose, each cooling hole 50, 52 opens in a corresponding main space 80A, 82A in the vicinity of the inner space E1 and in particular of the inner surface 74A, 76A of the cooling wall of the cooling element with which it is associated. The distance between the outlet of a cooling hole 50, 52 and the inner surface of the cooling wall of the cooling element with which it is associated, measured along the central axis of each cooling hole 50, 52, is for example less than 5 mm.

The diameter of each cooling hole 50, 52 is between 20mm and 100mm, preferably between 30mm and 50 mm.

In a variant, the cooling holes 50, 52 are not circular, but rather are oval or bean-shaped. The surface area of the cross-section of each cooling hole 50, 52 in a direction perpendicular to the axis through the hole is, for example, 12.56cm ²And 3.14cm ²Preferably at 27cm ²And 78cm ²In the meantime.

The inner surfaces 74A, 76A and outer surfaces 74B, 76B are generally smooth and free of projecting elements, and advantageously are generally smooth adjustment surfaces free of projecting elements.

"adjustment service" refers to a surface in which every point a line passes through the surface, called a generatrix (generatrix), is contained.

A smooth surface without protruding elements refers to a surface without irregularities or discontinuities.

Like the cooling walls 74, 76, the inner surfaces 74A, 76A and the outer surfaces 74B, 76B are advantageously in the form of conical or cylindrical bodies extending along the rotational axis R of the rotor 32.

Advantageously, and as shown in fig. 2, each cooling wall 74, 76 and therefore each inner surface 74A, 76A and each outer surface 74B, 76B is conical body-shaped, with a small base positioned on the side of the rotor 32 and a large base positioned opposite the rotor along the rotation axis R of the rotor. Each cooling wall 74, 76 is then inclined with respect to the rotation axis R and forms an angle with the rotation axis of between 20 ° and 70 °, preferably between 25 ° and 55 °.

The operation of the motor 22, and in particular the cooling of the motor 22, will now be described with reference to fig. 2.

When the rail vehicle 10 is in motion and the electric motors 22 are operating, the rotor 32 of each motor 22 rotates to cause the axles 20 of the trucks 16, 18 to be in motion. In each electric motor 22, the rotor 32 and stator 34 then release heat, which can affect the performance of the electric motor 22 when too much heat is available.

However, due to the cooling device 36 fixed to the rotor 32, when the rotor 32 rotates, the air in the inner space E1 is cooled, and the rotor 32 and the stator 34 are thus cooled.

More specifically, the cooling elements 74, 76 rotate and the cooling walls 74, 76 rotate accordingly, which causes circulation of air. The air circulation is done through the cooling holes 50, 52 from the outer space E2 towards the inner space E1 and in particular towards the main spaces 80A, 82A, and then from the inner space E1 and in particular the main spaces 80A, 82A towards the outer space E2. Both cooling holes 50, 52 are used as air inlet ducts into the interior space E1 and in particular the main spaces 80A, 82A and air outlet ducts from the interior space E1 and in particular the main spaces 80A, 82A.

The air circulation thus makes it possible to cool the air in the interior space E1 and in particular in the primary spaces 80A, 82A and thus to cool each cooling wall 74, 76 and thus to cool the air in each secondary space 80B, 82B by heat transfer. Thus, the heating of the rotor 32 and stator 34 is maintained within a thermal range that allows for optimal operation of the electric motor 22.

The normal rotation speed of the motor makes it possible to optimize the air circulation and therefore the heat exchange before cooling the inner space E1.

Furthermore, the fact that the outer surfaces 74B, 76B and the inner surfaces 74A, 76A are of conical shape and smooth in body makes it possible to optimize the dimensions and therefore the heat exchange while limiting the noise caused by the cooling device 36 and the mechanical losses associated with the rotation of the cooling device 36.

Furthermore, the invention has the advantage of being simple in construction and inexpensive to implement. In practice, the structure of the cooling device 36 is relatively simple.

The embodiments and alternatives considered above can be combined with each other to create new embodiments of the invention.