In-line circulation balanced bore structure electronic water pump

Abstract

The utility model discloses a kind of electronic water pumps with internal circulation balance hole structure, belong to fluid machinery technical field.The water pump includes volute, impeller, casing, bearing seat and motor assembly.The core improvement is that: balance hole is opened in the back cover plate of impeller and is communicated with import low pressure area, and the mouth ring stop is set in the front end of casing, and the mouth ring stop and the mouth ring of the back of impeller form the tiny gap of rotation cooperation, to form low pressure area below the mouth ring of the back of impeller, and jointly act with high pressure area above the mouth ring, effectively offset the axial force generated by impeller rotation, reduce bearing load and wear.The utility model also forms closed internal circulation flow channel by casing, shield sleeve and bearing seat, and designs multiple cooling circuits, respectively to motor rotor, control module and bearing carry out high-efficiency heat dissipation.The utility model structure is simple and compact, axial force balance effect is good, operating noise is low, reliability is high, applicable to automobile cooling system and various miniaturization water circulation scene.

Description

Technical Field

[0001] This utility model belongs to the field of electronic water pump technology, and relates to an electronic water pump with an internal circulation balance hole structure. Background Technology

[0002] During operation, the impeller of an electric water pump generates axial force due to the pressure difference between the front and rear cover plates. This axial force acts directly on the bearings of the drive motor, leading to accelerated bearing wear, increased operating noise, and a significant reduction in the pump's lifespan over time. There are two main traditional methods to address this axial force: 1. It adopts a double-suction impeller structure, which offsets the axial force through symmetrical design. However, this structure increases the size and weight of the impeller, making it unsuitable for miniaturized electric water pumps.

[0003] 2. Additional components such as balance discs and balance drums are added to balance the axial force through an external flow path. However, such structures are complex and require precise control of the fitting clearance, which not only increases the production difficulty but also increases the maintenance cost of the water pump. Furthermore, they are prone to clogging by impurities, leading to balancing failure. Summary of the Invention

[0004] This invention addresses the aforementioned problems by providing an electronic water pump with an internal circulation balance hole structure. This electronic water pump achieves axial balance through a simple hole design, balancing structural simplification and effective balancing. According to the technical solution of this utility model: an electronic water pump with an internal circulation balance hole structure includes a volute, an impeller, a housing, a bearing seat, a shaft, a motor rotor, and a motor stator. A connector is fixed to the outside of the bearing seat, and the connector is fixedly connected to the controller cover. The motor stator is fixed to the housing, and the motor rotor is mounted on the shaft and rotates synchronously with the shaft. Its features are: The front end of the housing is connected to the volute, and the rear end is connected to the bearing seat. A shielding sleeve is fixedly installed inside the housing, which separates the motor stator from the motor rotor. The rear cover plate of the impeller has several balance holes, which are connected to the low-pressure area of ​​the impeller inlet. The front end of the housing is provided with a front bearing cover. One end of the shaft is rotatably supported on the bearing seat, and the other end is rotatably supported on the front bearing cover. The impeller is mounted on the shaft. The outer end face of the front bearing cover is provided with a mouth ring stop. The mouth ring stop cooperates with the mouth ring on the back of the impeller to form a rotary sealing gap, so as to form a low-pressure area below the mouth ring, thereby counteracting the axial force generated when the impeller rotates.

[0005] As a further improvement of this utility model, one end of the shielding sleeve is sealed to the bearing seat, and the other end is sealed to the inner hole stop of the housing.

[0006] As a further improvement of this utility model, a return hole is provided on the housing to guide the high-pressure fluid from the impeller outlet to the flow channel between the shield sleeve and the motor rotor, forming a first flushing circuit for cooling the motor rotor.

[0007] As a further improvement of this utility model, the first flushing circuit flows to the control module side through the flow groove of the bearing housing, and then flows back to the impeller inlet through the shaft hole in the shaft; The control module is installed between the bearing housing and the controller cover.

[0008] As a further improvement of this utility model, the high-pressure fluid at the impeller outlet flows back to the impeller inlet through the gap between the inlet ring and the stop of the inlet ring, and through the balance hole, forming a second flushing circuit for axial force balance.

[0009] As a further improvement of this utility model, the front bearing cover is provided with a front bearing cover return hole. The high-pressure fluid flows through the flow hole of the thrust plate and the front bearing clearance, flows into the low-pressure area below the inlet ring, and then flows back to the impeller inlet through the balance hole, forming a third flushing circuit for cooling the front bearing. The thrust disc is mounted on the shaft.

[0010] As a further improvement of this utility model, the diameter and number of the balancing holes are optimized to reduce the volume loss from the high-pressure area to the low-pressure area.

[0011] The technical advantages of this utility model are as follows: This utility model has a good balancing effect. The balancing hole and the design of the mouth ring at the rear cover plate make the high-pressure area on both sides of the impeller similar, which cancels the axial force, reduces the load on the bearing, reduces wear, and reduces operating noise.

[0012] The structure is simplified, eliminating the need for additional components such as balance discs and balance drums. Axial force balance can be achieved simply by using the balance holes on the impeller in conjunction with the ring design at the rear cover plate, which simplifies the overall structure of the water pump and reduces the difficulty of production and assembly.

[0013] The integrated design incorporates stator support components and sliding bearings, separates high and low pressure zones on the impeller back, and forms a seal with the shielding sleeve. It also controls volumetric losses caused by backflow from the high-pressure zone into the balance hole. Its compact structure and small size allow it to be adapted to various sizes of miniaturized electric water pumps, making it suitable for applications such as automotive cooling systems, household appliance water circulation systems, and small industrial circulation systems.

[0014] The efficiency loss is small. By optimizing the diameter and number of balancing holes and the design of the mouth ring, the volume loss from the high-pressure area to the low-pressure area is reduced. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model.

[0016] Figure 2 This is a schematic diagram of the first flushing circuit structure of this utility model.

[0017] Figure 3 This is a schematic diagram of the second flushing circuit structure of this utility model.

[0018] Figure 4 This is a schematic diagram of the third flushing circuit structure of this utility model.

[0019] Figure 5 This is a schematic diagram of the impeller structure.

[0020] Figure 6 for Figure 5 Top view. Detailed Implementation

[0021] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0023] Figure 1-6 The components include a volute 1, impeller 2, balance hole 2-1, mouth ring 2-2, shielding sleeve 3, motor rotor 4, housing 5, front bearing cover 5-1, mouth ring stop 5-11, return hole 5-12, bearing seat 6, first bearing shell 7, thrust plate 8, motor stator 9, second bearing shell 10, shaft 11, control module 12, etc.

[0024] like Figure 1-6 As shown, this utility model is an electronic water pump with an internal circulation balance hole structure, including a volute 1, an impeller 2, a housing 5, a bearing seat 6, a shaft 11, a motor rotor 4, and a motor stator 9. The motor stator 9 is fixed inside the housing 5, and the motor rotor 4 is mounted on the shaft 11 and rotates synchronously with the shaft. A connector is provided on the outside of the bearing seat 6 for fixed connection with the controller cover. A control module 12 can be installed inside the controller cover to realize the operation control of the water pump.

[0025] The housing 5 serves as the main structural support component, with its front end connected to the volute 1 and its rear end connected to the bearing housing 6. A shielding sleeve 3 is installed inside the housing 5. One end of the shielding sleeve 3 is sealed to the inner bore stop of the housing 5, and the other end is sealed to the bearing housing 6, thereby completely isolating the motor stator 9 from the motor rotor 4 located in the wet cavity, preventing the working medium from entering the stator windings and ensuring electrical safety.

[0026] Impeller 2 is mounted at the front end of shaft 11 and located inside volute 1. Multiple balancing holes 2-1 are circumferentially formed on the rear cover plate of impeller 2. These balancing holes 2-1 connect a specific area on the back of impeller 2 with the low-pressure area at the impeller inlet.

[0027] A front bearing cover 5-1 is provided at the front end of the housing 5. One end of the shaft 11 is supported on the bearing seat 6 by the second bearing bush 10, and the other end is supported on the front bearing cover 5-1 by the first bearing bush 7. A stop ring 5-11 is provided on the side of the front bearing cover 5-1 facing the impeller 2. The stop ring 5-11 and the stop ring 2-2 provided on the back of the impeller 2 form a precise rotary seal gap. This gap ensures the free rotation of the impeller and also throttles the fluid, thereby forming a low-pressure zone below the stop ring 2-2 with a pressure similar to that of the impeller inlet, and a high-pressure zone above the stop ring 2-2 and on the side of the impeller front cover plate. Through the pressure action area of ​​the high and low pressure zones on the front and rear cover plates of the impeller, axial forces in opposite directions are generated and cancel each other out, significantly reducing the axial load acting on the thrust disc 8 and the first bearing bush 7, and achieving internal circulation balance of axial force.

[0028] To further optimize pump performance and achieve multi-functional integration, this utility model incorporates a three-way internal circulation flushing circuit within the housing 5: like Figure 1 , 2 As shown, the first flushing circuit (motor and control module cooling circuit): A return flow hole 5-12 is provided on the housing 5 to guide a portion of the high-pressure fluid from the impeller 2 outlet to the annular flow channel between the shielding sleeve 3 and the motor rotor 4, directly flushing the surface of the motor rotor 4 for cooling. Subsequently, the fluid flows through the flow groove provided on the bearing housing 6 to cool the control module 12 installed behind the bearing housing 6, and finally flows back to the low-pressure area at the impeller 2 inlet through the shaft hole inside the shaft 11 or the bearing clearance, completing the circulation.

[0029] like Figure 1 , 3 As shown, the second flushing circuit (axial force balancing main circuit): another portion of the high-pressure fluid at the outlet of impeller 2 enters the high-pressure zone above the inlet ring on the back of the impeller through the tiny gap between the inlet ring 2-2 and the inlet ring stop 5-11, and then flows back quickly to the low-pressure zone at the impeller inlet directly through the balance hole 2-1 on the impeller back cover plate. This circuit is the main path for generating dynamic pressure balance and counteracting axial force.

[0030] like Figure 1 , 4 As shown, the third flushing circuit (front bearing cooling and auxiliary balancing circuit): The front bearing cover 5-1 is provided with a front bearing cover return hole (not separately marked in the figure, it can be regarded as part of the return hole 5-12 or set independently). A portion of the high-pressure fluid flows through this hole through the flow hole of the thrust disk 8 mounted on the shaft 11, and enters the lubrication gap between the first bearing shell 7 and the shaft 11 to lubricate and cool the front bearing. Afterwards, the fluid enters the low-pressure zone below the inlet ring 2-2, and finally returns to the impeller inlet through the balancing hole 2-1. This circuit, while cooling the front bearing, also helps to enhance the axial force balancing effect.

[0031] In this invention, the diameter, number, and distribution of the balance holes 2-1 are optimized to ensure effective axial force balance while minimizing fluid leakage (volume loss) from the high-pressure zone to the low-pressure zone, thereby maintaining the pump's operating efficiency. The small gap between the inlet ring 2-2 and the inlet ring stop forms a rotational fit, preventing large-scale influx of high-pressure water into the low-pressure zone and also effectively reducing volume loss.

[0032] In addition, the housing 5, shielding sleeve 3 and bearing seat 6 are connected by a stop and fasteners, and a sealing ring is set on the mating surface to form a closed internal circulation channel, ensuring that the working medium (such as coolant) circulates in the pump without leakage.

[0033] This utility model integrates axial force balancing, motor cooling, bearing lubrication, and control module heat dissipation through the above structure. It has a compact structure, good balancing effect, and reliable operation, and is especially suitable for miniaturized application scenarios such as automotive cooling systems and home appliance water circulation systems where space and reliability requirements are high.

[0034] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although this utility model has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model.

Claims

1. An electronic water pump with an internal circulation balance hole structure, comprising a volute (1), an impeller (2), a housing (5), a bearing seat (6), a shaft (11), a motor rotor (4), and a motor stator (9), wherein a connector is fixed to the outside of the bearing seat (6), the connector is fixedly connected to a controller cover, the motor stator (9) is fixed to the housing (5), and the motor rotor (4) is mounted on the shaft (11) and rotates synchronously with the shaft (11), characterized in that: The front end of the housing (5) is connected to the volute (1), and the rear end is connected to the bearing seat (6). A shielding sleeve (3) is fixedly installed inside the housing (5), and the shielding sleeve (3) separates the motor stator (9) from the motor rotor (4). The impeller (2) has several balance holes (2-1) on its rear cover plate, and the balance holes (2-1) are connected to the low-pressure area at the inlet of the impeller (2). The front end of the housing (5) is provided with a front bearing cover (5-1). One end of the shaft (11) is rotatably supported on the bearing seat (6), and the other end is rotatably supported on the front bearing cover (5-1). The impeller (2) is installed on the shaft (11). The outer end face of the front bearing cover (5-1) is provided with a mouth ring stop (5-11). The mouth ring stop (5-11) and the mouth ring (2-2) on the back of the impeller (2) cooperate to form a rotary sealing gap, so as to form a low pressure area below the mouth ring (2-2), thereby offsetting the axial force generated when the impeller rotates.

2. The electronic water pump with an internal circulation balance hole structure as described in claim 1, characterized in that: One end of the shielding sleeve (3) is sealed to the bearing seat (6), and the other end is sealed to the inner hole stop of the housing (5).

3. The electronic water pump with an internal circulation balance hole structure as described in claim 1, characterized in that: The housing (5) has a return hole (5-12) for guiding the high-pressure fluid from the outlet of the impeller (2) to the flow channel between the shield sleeve (3) and the motor rotor (4) to form a first flushing circuit for cooling the motor rotor (4).

4. The electronic water pump with an internal circulation balance hole structure as described in claim 3, characterized in that: The first flushing circuit flows through the flow groove of the bearing housing (6) to the control module (12) side, and then flows back to the impeller (2) inlet through the shaft hole in the shaft (11); The control module (12) is installed between the bearing housing (6) and the controller cover.

5. The electronic water pump with an internal circulation balance hole structure as described in claim 1, characterized in that: The high-pressure fluid at the outlet of the impeller (2) flows back to the impeller inlet through the gap between the mouth ring (2-2) and the mouth ring stop (5-11), forming a second flushing circuit for axial force balance.

6. The electronic water pump with an internal circulation balance hole structure as described in claim 1, characterized in that: The front bearing cover (5-1) is provided with a front bearing cover return hole (5-12). The high-pressure fluid flows through the flow hole of the thrust plate (8) and the front bearing clearance, flows into the low-pressure area below the inlet ring (2-2), and then flows back to the impeller inlet through the balance hole (2-1), forming a third flushing circuit for cooling the front bearing. The thrust disk (8) is mounted on the shaft (11).

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