Oil-cooled motor stator cooling structure and motor thereof

Abstract

The utility model discloses an oil cooling motor stator cooling structure and motor, including motor casing and setting in the stator of motor casing, the stator includes stator core and winding, the motor casing is opened with oil inlet hole and internal oil circuit, the internal oil circuit is configured as the cooling oil that enters from the oil inlet hole is divided into first branch, second branch and third branch: first branch is guided to the space formed between the motor casing inner wall and the stator core outer surface, second branch and third branch are guided to the axial both ends of stator core respectively, and cooling oil is sprayed to the end of winding through the oil injection hole of several that sets up in the end of motor casing. By canceling independent oil shower ring, on the motor casing integrated design can shunt cooling oil to the internal oil channel of three branchs, and directly setting up the oil injection hole of many circles at the both ends of casing, has the effect that the structure is simplified, cost reduction and cooling performance promotion.

Description

Technical Field

[0001] This utility model relates to the technical field of heat dissipation and cooling structure for oil-cooled motors, specifically to a stator cooling structure for an oil-cooled motor and the motor thereof. Background Technology

[0002] In existing technologies, a common solution for winding cooling is to install a dedicated oil-drenching ring component inside the motor housing. Cooling oil enters the stator axial oil groove through the outer casing oil channels and flows to the oil-drenching rings at both ends of the stator, where it is sprayed onto the winding ends through oil holes. However, this solution has several drawbacks: First, the oil-drenching ring typically only has a single loop of oil holes, resulting in limited spray coverage and oil distribution uniformity, making it difficult to handle the concentrated heat generated by high-loss-density windings and prone to localized overheating. Second, as a separate component, the oil-drenching ring increases the motor's material cost, manufacturing complexity, and assembly steps.

[0003] To address the issues of oil guidance and utilization efficiency, existing technologies have proposed an improved solution. For example, Chinese invention patent CN101777816B discloses a motor oil cooling structure with a guide step. This solution uses a specific guide step (such as a cylindrical or V-shaped step) between the oil outlet and the winding to guide the cooling oil flowing from the oil passage more accurately onto the winding coil, thus preventing oil from flowing down the inner wall of the housing due to surface tension. While this solution improves the accuracy of oil guidance, it does not overcome the increased structural complexity and cost caused by relying on additional components (the guide step). The guide step itself is a component that needs to be manufactured and installed separately, which also increases process complexity and manufacturing costs.

[0004] It is evident that existing oil-cooled motor structures, whether employing the basic oil-drenching ring scheme or the improved scheme with added guide steps, fail to adequately balance multiple requirements such as cooling uniformity, structural simplicity, and low manufacturing cost. Utility Model Content

[0005] The technical problem to be solved by this invention is how to achieve uniform and efficient cooling of the stator core and winding ends without introducing additional complex components.

[0006] In a first aspect, to solve the above-mentioned technical problems, this utility model provides an oil-cooled motor stator cooling structure, including a motor housing and a stator disposed within the motor housing. The stator includes a stator core and windings. The motor housing has an oil inlet and an internal oil passage. The internal oil passage is configured to divide the cooling oil entering from the oil inlet into a first branch, a second branch, and a third branch. The first branch is guided to the space formed between the inner wall of the motor housing and the outer surface of the stator core; The second and third branches are respectively guided to the two ends of the stator core, and cool oil is sprayed onto the ends of the windings through a plurality of oil spray holes opened at the end of the motor housing.

[0007] Furthermore, the second branch and the third branch enter the welding end and the crown end respectively through the oil passage inside the motor housing and are sprayed onto the end of the winding through the oil injection hole.

[0008] Furthermore, the oil injection holes are evenly spaced along the circumference of the motor housing.

[0009] Furthermore, the oil injection holes are arranged in two rings at an axial distance at the end of the motor housing, and the two rings of oil injection holes are evenly staggered in the circumferential direction.

[0010] Furthermore, the outer surface of the stator core is provided with a plurality of axially extending oil grooves.

[0011] Furthermore, the cross-sectional shape of the oil groove is serrated or arc-shaped.

[0012] Furthermore, the oil inlet hole is located at the middle position of the end of the motor housing.

[0013] A second aspect of this utility model provides an electric motor, including the aforementioned oil-cooled motor stator cooling structure.

[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention eliminates the independent oil spray ring and integrates an internal oil passage on the motor housing that can divert cooling oil to three branches. Multiple oil spray holes are directly set at both ends of the housing, achieving the effects of simplified structure, reduced cost, and improved cooling performance. Attached Figure Description

[0015] Figure 1 This is a schematic axial cross-sectional view of the motor disclosed in an embodiment of the present utility model; Figure 2 This is a schematic diagram of the radial cross-section of the stator core disclosed in an embodiment of the present utility model.

[0016] In the picture: 10. Motor housing; 11. Oil inlet; 12. First branch; 13. Second branch; 14. Third branch; 15. Oil injection hole; 21. Stator core; 22. Welded end; 23. Crown end; 24. Oil groove. Detailed Implementation

[0017] To make the technical solutions and effects of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0018] The present invention aims to provide a cooling structure for the stator of an oil-cooled motor, which achieves uniform and efficient cooling of the stator core and winding ends without introducing additional complex components.

[0019] like Figure 1-2 As shown, the motor includes a motor housing 10 and a stator disposed within the motor housing 10. The stator includes a stator core 21 and a winding. The two ends of the winding are a welded end 22 and a crown end 23. The welded end 22 is the end of the winding coil and is connected to other conductive components (such as leads, busbars, commutators, or slip rings) through a welding process. It is the key node for the winding to achieve electrical conduction.

[0020] In this design, the motor housing 10 has an oil inlet 11 and an internal oil passage. The internal oil passage is configured to divide the cooling oil entering from the oil inlet 11 into a first branch 12, a second branch 13, and a third branch 14, wherein: The first branch 12 is guided to the space formed between the inner wall of the motor housing 10 and the outer surface of the stator core 21 for cooling the stator core 21.

[0021] The second branch 13 and the third branch 14 are respectively guided to the two axial ends of the stator core 21, and the cooling oil is sprayed onto the ends of the windings through a plurality of oil spray holes 15 opened at the ends of the motor housing 10. Specifically, the second branch 13 and the third branch 14 enter the welding end 22 and the crown end 23 through the oil passage inside the motor housing 10, respectively, and are sprayed onto the ends of the windings through the oil spray holes 15 for cooling the ends of the windings.

[0022] In this scheme, the cooling oil of the first branch 12 can be connected to the initial part of the oil pipelines of the second branch 13 and the third branch 14 through the oil hole.

[0023] In a further embodiment, the oil inlet 11 is located at the middle of the end of the motor housing 10. The oil injection holes 15 are evenly spaced along the circumference of the motor housing 10.

[0024] In a specific example, two rings of oil injection holes 15 are axially spaced at the end of the motor housing 10, and the two rings of oil injection holes 15 are evenly staggered in the circumferential direction to form a more uniform oil film coverage.

[0025] In a further embodiment, the outer surface of the stator core 21 is provided with multiple axially extending oil grooves 24. The cross-sectional shape of the oil grooves 24 is serrated or arc-shaped to increase the heat exchange area between the stator core 21 and the cooling oil.

[0026] During operation, cooling oil enters the oil circuit system integrated inside the motor housing 10 through the oil inlet 11. This oil circuit system efficiently distributes the cooling oil to three independent cooling branches, achieving coordinated and precise cooling of the stator.

[0027] Cooling of the first branch 12 pairs of stator cores 21: The first branch 12 guides a portion of the cooling oil directly to the annular space between the inner wall of the motor housing 10 and the outer surface of the stator core 21. The oil flows in this space and comes into direct contact with the outer surface of the stator core 21.

[0028] Cooling of the winding ends by the second branch 13 and the third branch 14: The second branch 13 and the third branch 14 guide the cooling oil to the two axial ends of the stator, namely the weld end 22 and the crown end 23, respectively. Under pressure, the oil is sprayed out from multiple rows of oil spray holes 15 opened on the housing areas at both ends. The sprayed oil droplets or oil jets directly and evenly cover the surfaces of the winding ends at both ends, efficiently absorbing and carrying away the main heat generated by the windings through direct contact and flow.

[0029] In this solution, the entire stator cooling structure does not require any separate oil spray ring parts or guide steps. The internal oil passages that can be integrated into the motor housing can distribute the cooling oil to three branches, and multiple oil spray holes are directly set at both ends of the housing, which has the effects of simplified structure, reduced cost and improved cooling performance.

[0030] In addition, this utility model also provides an electric motor, which includes the above-mentioned oil-cooled motor stator cooling structure.

[0031] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A cooling structure for an oil-cooled motor stator, comprising a motor housing (10) and a stator disposed within the motor housing (10), the stator comprising a stator core (21) and windings, characterized in that, The motor housing (10) has an oil inlet (11) and an internal oil passage. The internal oil passage is configured to divide the cooling oil entering from the oil inlet (11) into a first branch (12), a second branch (13), and a third branch (14). The first branch (12) is guided to the space formed between the inner wall of the motor housing (10) and the outer surface of the stator core (21); The second branch (13) and the third branch (14) are respectively guided to the two ends of the stator core (21), and the cooling oil is sprayed to the end of the winding through a plurality of oil spray holes (15) opened at the end of the motor housing (10).

2. The oil-cooled motor stator cooling structure according to claim 1, characterized in that, The second branch (13) and the third branch (14) enter the welding end (22) and crown end (23) respectively through the oil passage inside the motor housing (10) and are sprayed onto the end of the winding through the oil injection hole (15).

3. The oil-cooled motor stator cooling structure according to claim 1, characterized in that, The oil injection holes (15) are evenly spaced along the circumference of the motor housing (10).

4. The oil-cooled motor stator cooling structure according to claim 1, characterized in that, The oil injection holes (15) are arranged in two rings at an axial interval at the end of the motor housing (10), and the two rings of oil injection holes (15) are evenly staggered in the circumferential direction.

5. The oil-cooled motor stator cooling structure according to claim 1, characterized in that, The outer surface of the stator core (21) is provided with a plurality of axially extending oil grooves (24).

6. The oil-cooled motor stator cooling structure according to claim 5, characterized in that, The cross-sectional shape of the oil tank (24) is serrated or arc-shaped.

7. The oil-cooled motor stator cooling structure according to claim 1, characterized in that, The oil inlet (11) is located at the middle position of the end of the motor housing (10).

8. An electric motor, characterized in that, Includes the oil-cooled motor stator cooling structure as described in any one of claims 1-7.

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