CN112701854A - Oil cooling stator structure - Google Patents

Abstract

The invention discloses an oil-cooled stator structure, which is characterized by comprising: a motor shell, a rear end cover and a stator; the stator comprises a stator end coil and a stator iron core; the end parts of the rear end cover and the motor shell are provided with circumferential oil grooves, cooling oil enters the oil grooves from the electrically-driven rear end cover and is led into the electrically-driven upper part along the oil grooves; an axial stator oil distributing passage is arranged on the outer circumference of the motor shell close to the upper part and is communicated with the oil groove; and the stator oil distribution passage is provided with oil spraying holes corresponding to the cooling parts, and cooling oil falls from the oil spraying holes to directionally cool a coil at the end part of the stator and the stator core. The oil of the electric drive rear end cover is introduced into the stator oil distribution passage above the electric drive, and the oil spraying holes corresponding to the cooling parts realize the directional cooling of the coil at the end part of the stator and the stator core, so that the problem of uneven cooling of the stator is solved.

Description

Oil cooling stator structure

Technical Field

The invention belongs to the technical field of oil cooling, and relates to an oil cooling stator structure.

Background

Along with the popularization of new energy automobiles, the market continuously improves the performance requirements of electric automobile power systems, the volume and the power density required by electric drive systems are higher and higher, namely the power system structure is required to be compact and light as much as possible, so that the market is a three-in-one product structure integrated by three units, namely a main push motor, a speed reducer and a controller. The traditional water cooling scheme cannot directly cool a heat source and has thermal resistance. There is a temperature gradient from the motor windings to the water cooled cabinet. The windings cannot be cooled directly, resulting in temperature build-up and formation of local hot spots. A direct cooling heat source is required to improve cooling efficiency. The oil has no influence on the magnetic circuit of the motor due to the characteristic of non-magnetic and non-conductive property, and the speed reducer has a large amount of lubricating and cooling oil, so that the oil is selected as an internal direct cooling medium, and the development trend of a new energy electric drive system is formed.

The cooling oil in the related designs at present usually falls directly to the stator end and the winding for cooling, which easily causes uneven cooling of the stator.

Disclosure of Invention

The invention aims to: an oil-cooled stator structure capable of directional cooling is provided.

The technical scheme of the invention is as follows: an oil-cooled stator structure comprising: a motor shell, a rear end cover and a stator;

the stator comprises a stator end coil and a stator iron core;

the end parts of the rear end cover and the motor shell are provided with circumferential oil grooves, cooling oil enters the oil grooves from the electrically-driven rear end cover and is led into the electrically-driven upper part along the oil grooves;

an axial stator oil distributing passage is arranged on the outer circumference of the motor shell close to the upper part and is communicated with the oil groove; and the stator oil distribution passage is internally provided with oil spraying holes corresponding to the cooling parts, and cooling oil falls down from the oil spraying holes to directionally cool a coil at the end part of the stator and the stator core.

The further technical scheme is as follows: the stator core is fixed in the motor shell through a long bolt, and a gap is reserved between the stator core and the motor shell.

The further technical scheme is as follows: the motor shell and the upper part of the bearing of the rear end cover are provided with oil blocking rib structures which are used for blocking cooling oil of the stator oil distribution passage, and the cooling oil is accumulated and falls to cool the bearing.

The further technical scheme is as follows: the stator oil distribution passage is sealed through an aluminum plate by adopting a welding process.

The further technical scheme is as follows: the welding process includes at least friction stir welding.

The further technical scheme is as follows: and the oil groove on the rear end cover is sealed by a metal sealing gasket or a sealing ring.

The invention has the advantages that:

the oil of the electric drive rear end cover is introduced into the stator oil distribution passage above the electric drive, and the oil spraying holes corresponding to the cooling parts realize the directional cooling of the coil at the end part of the stator and the stator core, so that the problem of uneven cooling of the stator is solved.

Drawings

The invention is further described with reference to the following figures and examples:

FIG. 1 is a schematic diagram of an electric drive with an oil-cooled stator structure as provided herein;

FIG. 2 is a cross-sectional view of an electric drive with an oil-cooled stator structure as provided herein;

FIG. 3 is a cross-section A-A of FIG. 2;

FIG. 4 is a schematic view of a rear end cover of an oil-cooled stator structure provided herein;

fig. 5 is a schematic view of a motor housing of an oil-cooled stator structure provided herein.

Wherein: 1. a motor housing; 11. an oil sump; 12. the stator is divided into oil ducts; 13. an oil spraying hole; 14. a long bolt; 2. a rear end cap; 21. an axial bore; 3. a stator; 31. a stator end coil; 32. a stator core; 4. an oil blocking rib structure; 5. a front bearing; 6. a rear bearing; 7. an aluminum plate.

Detailed Description

Example (b): the present application provides an oil-cooled stator structure, with reference to fig. 1 to 5 in combination, the oil-cooled stator structure comprising:motor casing 1,rear end cap 2,stator 3. Thestator 3 includes a statorend portion coil 31 and astator core 32.

Referring to fig. 1 to 3, therear end cover 2 and the end of themotor housing 1 are provided withcircumferential oil grooves 11, and cooling oil enters theoil grooves 11 from the electrically drivenrear end cover 2 and is introduced into the electrically driven upper side along theoil grooves 11; an axial statoroil distributing passage 12 is arranged on the outer circumference of themotor shell 1 close to the upper part, and the statoroil distributing passage 12 is communicated with theoil groove 11; the statoroil distribution passage 12 is provided withoil spraying holes 13 corresponding to cooling parts, and cooling oil falls from theoil spraying holes 13 to directionally cool the statorend portion coil 31 and thestator iron core 32.

Illustratively, referring to fig. 4 in combination, a main oil passage is introduced below themotor housing 1, and enters theoil sump 11 through anaxial bore 21 of therear end cover 2.

Referring to fig. 5 in combination, at least onestator oil sub-passage 12 is disposed near the upper portion of the outer circumference of themotor housing 1, and a plurality of parallelstator oil sub-passages 12 may be designed according to practical applications, for example, twostator oil sub-passages 12 are provided in the drawing. In each statoroil distribution passage 12, a plurality ofoil spraying holes 13 are provided as needed for cooling portions, and the positions of theoil spraying holes 13 correspond to the statorend portion coil 31 and thestator core 32, respectively, for example.

Alternatively, thestator core 32 is fixed in themotor housing 1 by thelong bolt 14, and a gap is left between the stator core and themotor housing 1, so that cooling of oil is facilitated.

The upper parts of the bearings of themotor shell 1 and therear end cover 2 are provided with oil blockingrib structures 4 for blocking cooling oil of the statoroil distribution passage 12, and the cooling oil is accumulated and falls to cool the bearings. The cooling oil liquid of whereabouts can not only cool off the bearing, but also can play lubricated effect to the bearing. Illustratively, the oil falling from the oil retainingrib structure 4 at the front end of themotor housing 1 cools and lubricates the front bearing 5, and the oil falling from the oil retainingrib structure 4 at the rear end of themotor housing 1 cools and lubricates therear bearing 6.

The statoroil distribution passage 12 is sealed by thealuminum plate 7 by a welding process. Optionally, the welding process comprises at least friction stir welding. In practical application, thealuminum plate 7 may be welded in other manners. After the statoroil distribution channel 12 is processed on the outer circumference of themotor shell 1, the outer surface is welded and sealed through thealuminum plate 7, the manufacturing difficulty of the statoroil distribution channel 12 is simplified, and meanwhile, the sealing performance of an oil path in themotor shell 1 is guaranteed.

Optionally, theoil groove 11 on therear end cover 2 is sealed by a metal sealing gasket or a sealing ring. Illustratively, theoil grooves 11 with corresponding positions and shapes are arranged on therear end cover 2 and themotor casing 1, and after therear end cover 2 and themotor casing 1 are sealed by a metal sealing gasket or a sealing ring, a circumferential oil guiding channel is formed between therear end cover 2 and themotor casing 1.

The oil-cooled stator structure utilizes the structural design of themotor shell 1 and therear end cover 2 to shunt an oil way, so that the cooling of the stator is ensured, an additional oil distributing structure, a copper pipe, an oil pipe and the like are not needed, and the integration level of oil-cooled drive is improved.

To sum up, the oil-cooled stator structure that this application provided introduces the stator branch oil duct of electric drive top through the fluid with electric drive rear end cap, through drenching the oilhole that corresponds to the cooling part, realizes the directional cooling to stator tip solenoid and stator core, has solved the inhomogeneous problem of stator cooling.

The terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying a number of the indicated technical features. Thus, a defined feature of "first", "second", may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

The above-mentioned serial numbers of the embodiments of the present application are merely for description and do not represent the merits of the embodiments.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (6)

1. An oil-cooled stator structure, comprising: a motor shell, a rear end cover and a stator;

the stator comprises a stator end coil and a stator iron core;

the end parts of the rear end cover and the motor shell are provided with circumferential oil grooves, cooling oil enters the oil grooves from the electrically-driven rear end cover and is led into the electrically-driven upper part along the oil grooves;

an axial stator oil distributing passage is arranged on the outer circumference of the motor shell close to the upper part and is communicated with the oil groove; and the stator oil distribution passage is internally provided with oil spraying holes corresponding to the cooling parts, and cooling oil falls down from the oil spraying holes to directionally cool a coil at the end part of the stator and the stator core.

2. The oil-cooled stator structure of claim 1, wherein the stator core is fixed in the motor housing by a long bolt with a gap therebetween.

3. The oil-cooled stator structure of claim 2, wherein the motor housing and the upper part of the bearing of the rear end cover are provided with oil blocking ribs for blocking the cooling oil in the stator oil distribution passage, and the cooling oil is accumulated and falls to cool the bearing.

4. The oil-cooled stator structure of claim 3, wherein the stator oil galleries are sealed by an aluminum plate using a welding process.

5. The oil cooled stator structure of claim 4, wherein the welding process comprises at least friction stir welding.

6. An oil-cooled stator structure according to any one of claims 1 to 5, characterized in that the oil groove in the rear end cover is sealed with a metal gasket or a sealing ring.

Images