KR102175796B1 - Electric water pump apparatus provided with improved assembly structure between stator and housing - Google Patents

Abstract

According to the present invention, an electric water pump apparatus with an improved assembly structure of a stator and a housing includes: a cylindrical housing with an open upper side; a stator including a core slid and combined with the housing and in which a plurality of soft-magnetic metal plates are stacked, and a printed circuit board placed in a lower part of the core and electrically connected with coils wound on the core; a stator cover placed in an upper part of the stator and combined with the housing so as to seal the open upper part of the housing; an impeller installed in the stator cover to be rotatable and rotated together with a rotator rotated by an electromagnetic interaction with the stator; and an impeller cover combined with the stator cover, covering and sealing an upper part of the impeller and including an inlet and an outlet for fluids. The electric water pump apparatus includes: a plurality of fixing pillar protrusions protruding from the inner wall of the housing toward the outer circumference surface of the core, elongated from an upper part of the housing in a direction in which the stator is assembled, thereby keeping in close contact with the outer circumference surface of the core by being permanently deformed while being worn out during a procedure in which the protrusions are assembled by the outer circumference surface of the core; and a pillar type placement part placed between the fixing pillar protrusions, and formed to be extended upward from the bottom of the inner wall of the housing, thereby supporting a specific part of the stator. Therefore, the present invention is capable of improving the durability, performance and quality of the electric water pump.

Description

Electric water pump apparatus provided with improved assembly structure between stator and housing}

The present invention relates to a water pump operated by electricity, and more particularly, to a water pump device used to circulate water for cooling a drive motor or an air conditioner in, for example, a hybrid vehicle or an electric vehicle.

In general, a water pump used in an internal combustion engine vehicle is employed to circulate coolant to prevent the engine block from being overheated by heat generated by the explosion stroke of the engine. In general, a water pump of an internal combustion engine vehicle has a mechanical water pump structure that circulates coolant by rotating an impeller of the water pump using the rotational force of the engine.

Meanwhile, the water pump may also be employed for cooling a turbocharger added to an internal combustion engine.

However, in recent years, there is a tendency that more and more vehicles employing electric motors as a driving source of automobiles. An electric motor used as a driving source of a vehicle, an inverter, or a battery supplying electric energy to the electric motor or inverter inevitably generates high heat during an operation process, and thus a cooling device is necessary. As eco-friendly vehicles that are replacing internal combustion engines, the demand for water pumps is also increasing for driving motors, inverters, or batteries used in electric vehicles (EV) and hybrid vehicles (HEVs). In eco-friendly vehicles, most of the water pumps are electric water pumps operated by electricity. Typically, an electric water pump used for cooling an internal combustion engine is a large capacity water pump of 150W or more. On the other hand, electric water pumps used for cooling electric vehicle batteries, drive motors, inverters, etc. are small-capacity water pumps of about 30 to 60W. On the other hand, a water pump used for circulation of water used as a heating refrigerant for an electric vehicle is about 20W.

The electric water pump includes a housing, a stator received in a sealed form in the housing, and an impeller rotated by a rotator rotated by an electromagnetic interaction with the stator.

An example of an electric water pump having such a structure is disclosed in Korean Patent Application Publication No. 2019-0033980.

However, in the conventional electric water pump, the material of the housing is made of aluminum alloy so that the stator accommodated in the housing is prevented from vibrating or moving with respect to the housing due to vibration generated when the impeller rotates. Because the vibration resistance of aluminum alloy is relatively good, it is due to the tendency to adopt aluminum material for parts where vibration occurs. However, the aluminum housing is difficult to process and has a high processing cost. In addition, there is a problem in that it is difficult to completely fix the stator to the aluminum housing in the process of assembling the stator to the aluminum housing. In particular, since the cross-sectional area of the printed circuit board coupled to the core of the stator is larger than the cross-sectional area of the core, there is a problem that the core is relatively moved by vibration inside the housing because a gap is inevitable between the core and the housing. When the core moves inside the housing, the magnetic force generated by the stator becomes uneven, resulting in deterioration of the performance of the electric water pump and deterioration of durability.

An object of the present invention was devised to solve the above-described problems, and by improving the assembly structure of the stator and the housing, the core constituting the stator maintains a state that is firmly assembled with the housing, thereby improving durability and performance quality. It is to provide an electric water pump device.

In order to achieve the above object, an electric water pump apparatus having an improved assembly structure of a stator and a housing according to an exemplary embodiment of the present invention includes: a cylinder-shaped housing with an upper side open;

A stator including a core on which a plurality of soft magnetic metal plates are stacked and a printed circuit board electrically connected to a coil wound on the core and disposed under the core, which is slidably coupled to the housing; And

A stator cover disposed on the stator and coupled to the housing to seal the open upper portion of the housing;

An impeller that is rotatably installed on the stator cover and rotates integrally with a rotator rotated by electromagnetic interaction with the stator; And

In the electric water pump comprising; an impeller cover coupled to the stator cover, covering and sealing an upper portion of the impeller, and having an inlet and an outlet for fluid,

It protrudes from the inner wall of the housing toward the outer circumferential surface of the core, and is formed to extend long in the direction in which the stator is assembled from the upper end of the housing, so that the stator is worn by the outer circumferential surface of the core during assembly to the housing. While being permanently deformed, a plurality of fixed pillar protrusions maintaining a state in close contact with the outer peripheral surface of the core are provided,

It is characterized in that it is disposed between the fixed pillar protrusions, is disposed to extend upward from the lower end of the inner wall of the housing, and has a columnar seating portion for supporting a specific portion of the stator.

A guide rail extending downward from the upper end of the housing and protruding from the inner wall of the housing toward the stator is provided,

It is preferable that the stator is provided with a sliding groove that is coupled to the guide rail and slides.

It is preferable that the housing is made of a synthetic resin material.

It is preferable that the cross-section of the fixed pillar protrusion is configured to have a smaller width toward the protruding end.

It is preferable that the cross section of the fixed pillar protrusion is made in the shape of ▷.

The electric water pump device having an improved assembly structure of a stator and a housing according to the present invention wears the fixed columnar projections as the outer peripheral surface of the core of the stator is combined with the fixed columnar projections provided in the housing in the combination structure of the housing and the stator. By forming a structure in which the fixed columnar protrusion and the outer circumferential surface of the stator are completely in close contact with each other so that permanent deformation occurs, the stator does not cause relative vibration to the housing, thereby improving the durability and performance quality of the electric water pump. Provides a lethal effect.

In addition, as in a preferred embodiment of the present invention, when the material of the housing is made of synthetic resin, it is easier to process, improves assembly properties, and significantly reduces manufacturing cost compared to the conventional aluminum housing.

In addition, as in a preferred embodiment of the present invention, when a columnar seating portion is provided in the housing, it is possible to more reliably prevent the vertical flow of the stator, thereby providing an effect of further increasing durability.

In addition, as in a preferred embodiment of the present invention, when a guide rail is provided in the housing and a sliding groove part that is slidably coupled to the guide rail is provided in the stator, the stator and the housing are prevented from being mis-assembled, thereby improving assembly performance. do.

1 is a perspective view of an electric water pump according to a preferred embodiment of the present invention.
2 is an exploded perspective view of the electric water pump shown in FIG. 1.
3 is a view showing in detail the internal structure of the housing shown in FIG. 1.
4 is a diagram showing the structure of a stator.
5 is a cross-sectional view taken along the line V-V shown in FIG. 1.
6 is a longitudinal cross-sectional view showing a structure in which the columnar seating portion supports the stator.
7 is a sectional view taken along the line VII-VII shown in FIG. 1.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a perspective view of an electric water pump according to a preferred embodiment of the present invention. 2 is an exploded perspective view of the electric water pump shown in FIG. 1. 3 is a view showing in detail the internal structure of the housing shown in FIG. 1. 4 is a diagram showing the structure of a stator. 5 is a cross-sectional view taken along the line V-V shown in FIG. 1. 6 is a longitudinal cross-sectional view showing a structure in which the columnar seating portion supports the stator. 7 is a sectional view taken along the line VII-VII shown in FIG. 1.

1 to 7, the electric water pump device 10 (hereinafter referred to as "electric water pump device") having an improved assembly structure of the stator and the housing according to the present invention is used in a range of about 15W to 60W Suitable for medium or small capacity electric water pumps.

The electric water pump device 10 includes a housing 20, a stator 30, a stator cover 40, a rotator 50, an impeller 60, and an impeller cover 70.

The housing 20 is a cylindrical structure with an open upper side. A connector portion 29 for supplying electricity to a stator 30 to be described later is provided on a lower surface of the housing 20. A cooling hole 28 is provided on the lower surface of the housing 20 so as to exchange heat generated from the stator 30 with external air. A membrane is coupled to the cooling hole 28. The membrane is a member having pores of a size that allows air particles to pass through and water particles to pass through. The material of the membrane may be a material such as so-called Gore-Tex.

A flange portion 25 to which a stator cover 40 to be described later is coupled is provided on an upper portion of the housing 20. The flange portion 25 is provided with a plurality of coupling holes. Through the coupling hole, the stator cover 40 may be firmly coupled through the housing 20 and the screw 46. The flange portion 25 is provided with a first sealing groove 27 in which the first sealing ring 81 is accommodated. The first sealing ring 81 is a ring-shaped member and may be made of a material such as rubber or silicone resin. The first sealing ring 81 is adopted to improve sealing properties with the stator cover 40 sealing the upper portion of the housing 20. The inside of the housing 20 may be completely watertight by the first sealing ring 81.

The stator 30 is slidingly coupled to the housing 20. More specifically, the stator 30 includes a core 32, a coil 34, and a printed circuit board 36.

The core 32 is composed of a number of soft magnetic metal plates laminated and bonded. The core 32 may be made of, for example, a low-carbon steel that can be easily magnetized. A space in which the rotator 50 can be disposed is provided in the center of the core 32. An insulating member is coupled to the upper and lower portions of the core 32. The outer peripheral surface of the core 32 is configured in a circular shape. The inner side of the core 32 forms an uneven structure including a plurality of teeth.

The coil 34 is wound around the uneven structure of the core 32. The surface of the coil 34 is covered with insulation. A plurality of coils 34 are wound. One end of the coil 34 is electrically connected to a printed circuit board 36 to be described later.

The printed circuit board 36 is disposed under the core 32. The printed circuit board 36 is fixed to the core 32. The printed circuit board 36 is electrically connected to the coil 34 wound around the core 32. The printed circuit board 36 controls the electricity supplied from the outside through the connector portion 29 provided in the housing 20 and transmits it to the coil 34. The outer diameter of the printed circuit board 36 is larger than the outer diameter of the core 32.

The stator cover 40 is disposed on the stator 30. The stator cover 40 is coupled to the housing 20 to seal the open upper portion of the housing 20. The stator cover 40 is fixed to the flange portion 25 of the housing 20 by a plurality of screws 46 via the first sealing ring 81. A rotator accommodating part 42 is provided in the center of the stator cover 40. The rotator accommodating portion 42 is formed to protrude downward from the center of the stator cover 40. The rotator accommodating portion 42 constitutes a cylindrical groove portion structure with an open upper side. A rotator 50 including a central shaft 43 and a permanent magnet is installed in the rotator receiving part 42. The rotator receiving part 42 serves to arrange a physically separated space while the rotator 50 and the stator 30 interact electromagnetically. Since water does not flow into the stator 30 by the rotator accommodating portion 42, the stator 30 in electrical contact is completely spatially separated from the rotator 50. Accordingly, the stator 30 is prevented from being damaged by moisture.

An impeller 60 that rotates integrally with the rotator 50 is installed on the stator cover 40. The rotator 50 and the impeller 60 are rotatably installed on the stator cover 40. The impeller 60 is provided with a plurality of pressure blades to pressurize water. A second sealing groove 76 is provided in the upper flange of the stator cover 40. The second sealing groove portion 76 is a concave groove portion opened upward and extends in a ring shape. The second sealing ring 82 is accommodated in the first sealing groove 27. The structure of the second sealing ring 82 may be the same or similar to the first sealing ring 81 described above.

The impeller cover 70 is coupled to the stator cover 40. The impeller cover 70 is a structure that covers and seals the upper portion of the impeller 60. The impeller cover 70 is provided with an inlet 72 and an outlet 74 through which liquid fluid such as water enters and exits. The inlet 72 and the outlet 74 may be disposed in a direction perpendicular to each other in space. The impeller cover 70 and the stator 30 are coupled to be watertight through the second sealing ring 82.

In this embodiment, the housing 20, the stator cover 40, and the impeller cover 70 are integrally fixed by a screw 46.

The inner circumferential surface of the housing 20 is provided with a fixed column protrusion 22, a columnar seating portion 24, and a guide rail 26.

The fixed pillar protrusion 22 protrudes from the inner wall of the housing 20 toward the outer peripheral surface of the core 32. The fixed pillar protrusion 22 is formed to extend long in a direction in which the stator 30 is assembled from an upper end of the housing 20. The fixed column protrusion 22 is permanently deformed while being worn by friction with the outer circumferential surface of the core 32 while the stator 30 is assembled to the housing 20. The upper end of the fixed pillar protrusion 22 has a tapered longitudinal sectional structure to facilitate entry when assembling the stator 30 to be described later.

The fixed pillar protrusion 22 maintains a state in close contact with the outer peripheral surface of the core 32. The cross-section of the fixed pillar protrusion 22 is configured to gradually decrease in width from the inner surface of the housing 20 to the outer surface of the core 32 in the state before being permanently deformed. For example, it is preferable that the cross section of the fixed pillar protrusion 22 forms a ▷-shaped structure. When the protruding end of the fixed column protrusion 22 is formed sharply in cross section, it is easily worn when combined with the outer circumferential surface of the core 32 to improve assembly. A plurality of fixed pillar protrusions 22 are provided in a form spaced apart along the circumferential direction of the inner peripheral surface of the housing 20. The fixed pillar protrusion 22 completely prevents flow in the radial direction of the housing 20 in a state in which the stator 30 is assembled to the housing 20. Accordingly, the stator 30 is prevented from flowing in the radial direction of the housing 20 with respect to the housing 20, thereby preventing the distribution of magnetic force from unexpectedly changing when the stator 30 is operated, thereby preventing the electric water pump device 10. Quality performance can be improved.

A plurality of columnar seating portions 24 are provided in a form spaced apart from each other in the circumferential direction of the inner side of the housing 20. The columnar seating portion 24 is disposed between the fixed column protrusions 22. The columnar seating portion 24 is formed to extend upward from the lower end of the inner wall of the housing 20. The upper end of the columnar seating portion 24 is disposed to support a specified portion of the stator 30. The columnar mounting portion 24 is provided with a groove for evacuation of the columnar mounting portion 24 in the printed circuit board 36 so as to avoid interference between the columnar mounting portion 24 and the printed circuit board 36.

The guide rail 26 is formed on the inner wall of the housing 20. The guide rail 26 extends downward from the upper end of the housing 20. The guide rail 26 is a structure protruding from the inner wall of the housing 20 toward the stator 30. The guide rail 26 may have, for example, a square column shape. The guide rail 26 is formed at a portion that does not interfere with the fixed pillar protrusion 22.

The stator 30 is provided with a sliding groove 38 coupled to the guide rail 26 and sliding. The guide rail 26 and the sliding groove 38 serve to guide the correct assembly position of the stator 30 in a process in which the housing 20 and the stator 30 are mutually assembled. Accordingly, the guide rail 26 and the sliding groove 38 provide an effect of preventing misassembly of the stator 30.

It is preferable that the housing 20 is made of a synthetic resin material. When the housing 20 is made of a synthetic resin material, the fixed column protrusion 22 integrally formed with the housing 20 is easily worn when combined with the core 32 to cause permanent deformation, so assembling is good. There is an advantage. As in the prior art, when the housing 20 is made of an aluminum material, the fixed column protrusion 22 is not easily worn when combined with the core 32, so assembly is difficult.

Hereinafter, the effect of the electric water pump device 10 including the above-described components will be described in detail by taking a process of assembling the stator 30 to the housing 20 as an example.

First, the stator 30 assumes that the core 32, the coil 34, and the printed circuit board 36 are pre-assembled. The stator 30 is brought close to the housing 20 from above the housing 20. The stator 30 is brought close to the housing 20 so that the guide rail 26 and the sliding groove 38 are coupled to each other. As the guide rail 26 and the sliding groove 38 are coupled, the stator 30 starts to be coupled to the inside of the housing 20. In this process, the printed circuit board 36 has an escape groove structure so as not to interfere with the fixed column protrusion 22 and the guide rail 26, and thus the housing 20 without interference with the housing 20 ). The outer circumferential surface of the core 32 interferes with the fixed pillar protrusion 22. At this time, the operator applies force to the stator 30 to forcefully push the stator 30 into the housing 20. In this process, the outer circumferential surface of the core 32 is rubbed against the fixed column protrusion 22, and the tip of the fixed column protrusion 22 is worn to cause permanent deformation. As this operation continues, the stator 30 is increasingly accommodated into the housing 20. The stator 30 is pressed until the stator 30 approaches the columnar seating portion 24. As the stator 30 approaches the columnar seating portion 24, the upper flange of the stator 30 is supported in contact with the flange portion of the housing 20.

Now, the stator cover 40 is coupled to the housing 20. The rotator 50 and the impeller 60 are installed on the stator cover 40. The stator cover 40 may be coupled to the housing 20 while the rotator 50 and the impeller 60 are installed on the stator cover 40. The impeller cover 70 is temporarily assembled to the stator cover 40. In that state, a plurality of screws 46 are screwed to the housing 20 by passing through the stator cover 40 from the impeller cover 70. In this process, the first sealing ring 81 and the second sealing ring 82 are pressed to realize a sealing effect, and the housing 20, the stator cover 40, and the impeller cover 70 are mutually firmly assembled. As a result, the electric water pump device 10 is assembled. As the first sealing ring 81 is pressed by the screw 46, the stator cover 40 is in close contact with the flange portion 25 of the housing 20, and at the same time, the columnar seating portion 24 is the stator. (30) will endorse a specific part.

As described above, in the electric water pump according to the present invention, since the fixed column protrusion prevents the flow in the radial direction of the stator, and the column-shaped seating portion and the stator cover cooperate to prevent the flow of the stator in the vertical direction, the flow of the stator with respect to the housing As this does not occur, the distribution of magnetic force generated in the stator is maintained constant, providing an effect of realizing stable water pump performance. In addition, compared to the conventional structure, since the stator is firmly assembled in the housing, the durability of the water pump is significantly improved. In addition, when the housing is made of a synthetic resin material, permanent deformation of the protrusions of the fixed pillars easily occurs, thereby providing an effect of improving assembly.

In the above, the present invention has been described in detail with reference to preferred embodiments, but the present invention is not limited to the above embodiment, and various modifications are possible by those of ordinary skill in the art within the technical spirit of the present invention. Is obvious.

10: electric water pump device
20: housing
22: fixed column projection
24: column type seating part
25: flange portion
26: guide rail
27: first sealing groove
28: cooling hole
29: connector part
30: stator
32: core
34: coil
36: printed circuit board
38: sliding groove
40: stator cover
42: rotator receiving part
43: central axis
46: screw
50: rotator
60: impeller
70: impeller cover
72: inlet
74: outlet
76: second sealing groove
81: first sealing ring
82: second sealing ring

Claims (5)

A cylinder-shaped housing whose upper side is open;
A stator including a core on which a plurality of soft magnetic metal plates are stacked and a printed circuit board electrically connected to a coil wound on the core and disposed under the core, which is slidably coupled to the housing; And
A stator cover disposed on the stator and coupled to the housing to seal the open upper portion of the housing;
An impeller that is rotatably installed on the stator cover and rotates integrally with a rotator rotated by electromagnetic interaction with the stator; And
In the electric water pump comprising; an impeller cover coupled to the stator cover, covering and sealing an upper portion of the impeller, and having an inlet and an outlet for fluid,
It protrudes from the inner wall of the housing toward the outer circumferential surface of the core, and is formed to extend long in the direction in which the stator is assembled from the upper end of the housing, so that the stator is worn by the outer circumferential surface of the core during assembly to the housing. While being permanently deformed, a plurality of fixed pillar protrusions maintaining a state in close contact with the outer peripheral surface of the core are provided,
It is disposed between the fixed pillar protrusions, is formed to extend upward from the lower end of the inner wall of the housing, and has a columnar seating portion for supporting a specific portion of the stator,
The housing is made of a synthetic resin material,
The electric water pump apparatus having an improved assembly structure of the stator and the housing, wherein the printed circuit board is provided with an evacuation groove so as to avoid interference with the printed circuit board. The method of claim 1,
A guide rail extending downward from the upper end of the housing and protruding from the inner wall of the housing toward the stator is provided,
The electric water pump device having an improved assembly structure of the stator and the housing, wherein the stator is provided with a sliding groove that is coupled to the guide rail and slides. delete The method of claim 1,
The electric water pump device having an improved assembly structure of the stator and the housing, characterized in that the cross-section of the fixed pillar protrusion is configured to decrease in width toward the protruding end. The method of claim 4,
The electric water pump device having an improved assembly structure of the stator and the housing, characterized in that the cross section of the fixed pillar protrusion has a ▷ shape.

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