Drain pump for a dishwasher
By employing a double-layer sealing ring structure and a tension connection method in the dishwasher drain pump, the problems of sealing ring aging and deformation displacement are solved, achieving a drain pump design with high sealing performance and long-term reliability.
Patent Information
- Application Number
- CN202522214096.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-20
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2035-10-20
AI Technical Summary
The sealing rings of existing dishwasher drain pumps are prone to aging and failure, resulting in reduced sealing performance. Furthermore, the tightening connection method causes deformation and displacement of the sealing rings, affecting their service life and reliability.
It adopts a double-layer sealing ring structure, with the integrated molded boss and annular step of the gland providing positioning and support. Combined with the irregular design of the annular groove and the tightening connection method, it avoids the deformation and displacement of the sealing ring caused by circumferential friction, thus ensuring the sealing performance.
Significantly reduces the risk of leakage, extends the service life of the sealing ring, and improves the long-term reliability and sealing performance of the drainage pump.
Smart Images
Figure CN224679708U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of drain pump technology, and in particular to a drain pump for a dishwasher. Background Technology
[0002] The dishwasher's drain pump is the core power component of the dishwasher's drainage system. Its main function is to quickly and thoroughly drain the wastewater from the dishwasher's washing chamber after the dishes have been washed and rinsed, through a pre-designed drain pipe. The operational stability of this component directly determines the dishwasher's drainage efficiency and reliability, and is one of the key components ensuring the normal operation of the dishwasher's overall functions.
[0003] A dishwasher's drain pump typically consists of a pump body, pump cover, drive structure, and impeller. The drive structure is located within the pump body and drives the impeller to rotate. The impeller is located within the impeller cavity formed by the pump body and pump cover. The pump cover has an inlet and an outlet. Inside the pump body, the core structure driving the impeller's rotation is the motor assembly, which generally includes a drive motor, a motor shaft, and a linkage structure. When the drive motor is energized, it generates rotational power, which is transmitted to the impeller through the motor shaft, causing the impeller to rotate at high speed. During rotation, the impeller blades exert centrifugal force on the wastewater, giving the wastewater kinetic energy and forcing it along the internal flow channels to the drain pipe, ultimately achieving wastewater discharge.
[0004] In the existing structural design of dishwasher drain pumps, the connection between the pump body and the pump cover is usually sealed with a single-layer sealing ring to prevent sewage leakage from the impeller cavity to the outside. However, this sealing method and the corresponding connection structure have significant defects. First, the single-layer sealing ring is prone to aging and failure. Because dishwasher drain pumps operate in a humid environment for extended periods, and the sewage may contain corrosive substances such as detergent residue, the single-layer sealing ring is highly susceptible to memory aging under continuous chemical erosion and physical wear. This leads to a gradual loss of elasticity and a significant decrease in sealing performance, ultimately causing leakage. Second, existing pump bodies and pump covers mostly use a screw-on connection method. During the tightening process, significant friction is generated between the pump cover and the sealing ring. This friction causes irregular deformation and displacement of the single-layer sealing ring between the pump body and the pump cover connection surface. This prevents the sealing ring from maintaining a uniform and tight fit with the connection surface, resulting not only in localized sealing failure and sewage leakage, but also further accelerating the aging rate of the sealing ring due to uneven stress, severely affecting the service life and normal performance of the drain pump. Summary of the Invention
[0005] In view of the shortcomings of the prior art, the technical problem to be solved by this patent application is how to provide a drain pump for a dishwasher that can provide double-layer sealing, stable connection and high sealing performance.
[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0007] A drain pump for a dishwasher includes a pump body and a pump cover. The pump body has a stator, the pump body has a rotor, and the rotor has a drive impeller. The drive impeller includes an impeller seat fixedly connected to the rotor and impeller blades fixedly mounted on the impeller seat. A pressure cover is fixedly mounted on the upper end of the pump body, the impeller seat is located above the pressure cover, the rotor passes through the pressure cover and is connected to the pressure cover via a sealed bearing, the pump body and the pump cover form an impeller cavity, the drive impeller is located within the impeller cavity, and the pump cover has an inlet and a outlet. The pump body is characterized in that...
[0008] The pressure cap has an integrally formed boss located below the impeller seat. The boss has two annular steps circumferentially arranged, and a sealing ring is placed on each annular step. The pump cover has an annular groove opposite the two annular steps, and the sealing ring is located in the annular groove. The pump cover is fixedly connected to the pressure cap.
[0009] In the above technical solution, the boss, integrally formed by the pressure cap, is located below the impeller seat, providing an installation carrier for the two sealing rings. Two annular steps circumferentially positioned on the boss provide precise circumferential positioning and support for the two sealing rings, allowing them to be stably placed on the step surface, avoiding the problem of arbitrary placement of sealing rings in traditional non-positioning structures. With two sealing rings, even if one layer of sealing rings shows slight aging due to long-term use, the other layer can still maintain its sealing effect, significantly reducing the risk of leakage. The annular groove on the pump cover, directly opposite the annular steps, forms a step-groove mating structure. When the sealing ring is compressed, the groove wall limits the sealing ring, providing circumferential constraint from the pump cover side. Combined with the supporting effect of the annular steps, the sealing ring is securely clamped. During the compression process, the pump cover has no circumferential sliding space relative to the pressure cap, completely avoiding the deformation and displacement problems caused by circumferential friction of the sealing ring in traditional tightening connections, ensuring the long-term reliable operation of the drainage pump.
[0010] When the stator is energized, it generates an alternating magnetic field, causing the rotor inside the pump body to produce a rotational torque under the action of the magnetic force. This torque, in turn, drives the impeller seat, which is fixedly connected to the rotor, to rotate synchronously. The impeller seat then directly transmits the rotational power to the impeller blades fixed on it, driving the entire impeller to rotate at high speed within the impeller cavity formed by the pump body and pump cover. The rotor passes through the gland and is connected by a sealed bearing, ensuring smooth rotor rotation and preventing sewage leakage from the impeller cavity into the stator and rotor areas inside the pump body. The gland and pump cover are sealed together by two sealing rings, further isolating the impeller cavity from the external environment and preventing sewage leakage from corroding the stator, rotor, and other electrical components.
[0011] Furthermore, the annular groove is composed of an upper flat annular surface, an inclined annular surface, and a side vertical annular surface connected in sequence, and the upper flat annular surface, the inclined annular surface, and the side vertical annular surface are in contact with the sealing ring.
[0012] Furthermore, both the vertical and lower annular surfaces of the annular step are provided with arc-shaped grooves, and the sealing ring contacts the arc-shaped grooves.
[0013] Furthermore, the pump cover is fixedly mounted downwards with several internally threaded cylinders, and the pressure cover is provided with through holes that allow the internally threaded cylinders to pass through. The tension bolt is threadedly connected to the internally threaded cylinders, and the end of the tension bolt abuts against the pressure cover.
[0014] Furthermore, it also includes a pressure ring, which is provided with an internal thread. An external threaded cylinder that can be threadedly connected to the pressure ring is fixedly installed on the pressure cover. The pump cover is provided with several notches at circumferential intervals, and a protrusion is formed between adjacent notches. The pressure ring is provided with a clearance opening opposite the protrusion.
[0015] Furthermore, the pressure ring is provided with a threaded hole, and a clamping bolt is connected in the threaded hole.
[0016] Furthermore, the outer side of the pressure ring is provided with a number of spaced-apart paddles.
[0017] In summary, the drain pump of this dishwasher has the advantages of providing a double seal, stable connection, and high sealing performance. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the drain pump of a dishwasher according to the present invention.
[0019] Figure 2 for Figure 1 A schematic diagram of the split structure.
[0020] Figure 3 for Figure 1 A schematic diagram of the dishwasher's drain pump without the pump cover and pressure ring.
[0021] Figure 4 This is a schematic diagram of the pump cover.
[0022] Figure 5 This is a schematic diagram of the pressure ring structure.
[0023] Figure 6 for Figure 3 A schematic diagram of the bottom structure.
[0024] Figure 7 This is a sectional view of the pump cover, boss, and gland.
[0025] Figure 8 for Figure 7 The front view.
[0026] Figure 9 for Figure 8 A magnified structural diagram of point A in the middle.
[0027] Figure 10 for Figure 8 A schematic diagram of the structure without the pump cover.
[0028] Figure 11 for Figure 10 A magnified structural diagram at point B in the middle. Detailed Implementation
[0029] The present invention will now be described in further detail with reference to the accompanying drawings. In the description of the present invention, it should be understood that directional terms such as "upper," "lower," "top," and "bottom" indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are used only for the convenience of describing the present invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of the present invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.
[0030] like Figure 1-11 As shown, a drain pump for a dishwasher includes a pump body 1 and a pump cover 2. The pump body 1 has a stator, and the pump body contains a rotor. The rotor has a drive impeller, which includes an impeller seat 3 fixedly connected to the rotor and impeller blades 4 fixedly mounted on the impeller seat. A pressure cover 5 is fixedly mounted on the upper end of the pump body. The impeller seat is located above the pressure cover. The rotor passes through the pressure cover and is connected to the pressure cover via a sealed bearing. The pump body and the pump cover form an impeller cavity, and the drive impeller is located within the impeller cavity. The pump cover has an inlet and a outlet. The pump body is characterized by...
[0031] The pressure cap has an integrally formed boss 6, which is located below the impeller seat. The boss has two annular steps 7 arranged around its circumference, and a sealing ring 8 is placed on each annular step. The pump cover has an annular groove 9 opposite the two annular steps, and the sealing ring is located in the annular groove. The pump cover is fixedly connected to the pressure cap.
[0032] In the above technical solution, the boss, integrally formed by the pressure cap, is located below the impeller seat, providing an installation carrier for the two sealing rings. Two annular steps circumferentially positioned on the boss provide precise circumferential positioning and support for the two sealing rings, allowing them to be stably placed on the step surface, avoiding the problem of arbitrary placement of sealing rings in traditional non-positioning structures. With two sealing rings, even if one layer of sealing rings shows slight aging due to long-term use, the other layer can still maintain its sealing effect, significantly reducing the risk of leakage. The annular groove on the pump cover, directly opposite the annular steps, forms a step-groove mating structure. When the sealing ring is compressed, the groove wall limits the sealing ring, providing circumferential constraint from the pump cover side. Combined with the supporting effect of the annular steps, the sealing ring is securely clamped. During the compression process, the pump cover has no circumferential sliding space relative to the pressure cap, completely avoiding the deformation and displacement problems caused by circumferential friction of the sealing ring in traditional tightening connections, ensuring the long-term reliable operation of the drainage pump.
[0033] When the stator is energized, it generates an alternating magnetic field, causing the rotor inside the pump body to produce a rotational torque under the action of the magnetic force. This torque, in turn, drives the impeller seat, which is fixedly connected to the rotor, to rotate synchronously. The impeller seat then directly transmits the rotational power to the impeller blades fixed on it, driving the entire impeller to rotate at high speed within the impeller cavity formed by the pump body and pump cover. The rotor passes through the gland and is connected by a sealed bearing, ensuring smooth rotor rotation and preventing sewage leakage from the impeller cavity into the stator and rotor areas inside the pump body. The gland and pump cover are sealed together by two sealing rings, further isolating the impeller cavity from the external environment and preventing sewage leakage from corroding the stator, rotor, and other electrical components.
[0034] In practice, the annular groove is composed of an upper flat annular surface 10, an inclined annular surface 11, and a side vertical annular surface 12 connected in sequence, and the upper flat annular surface, the inclined annular surface, and the side vertical annular surface are in contact with the sealing ring.
[0035] In this way, the annular groove is configured with an upper flat annular surface, an inclined annular surface, and a side vertical annular surface. The sealing ring contacts three surfaces. The inclined annular surface causes the sealing ring to generate a radial expansion force when subjected to axial compression, prompting the sealing ring to fit tightly against the inclined annular surface, the side vertical annular surface, and the annular step surface, respectively. The upper flat annular surface limits excessive axial deformation of the sealing ring, preventing it from losing elasticity due to excessive compression. The irregular structure of the annular groove guides the direction of deformation of the sealing ring under stress, enabling the sealing ring to form a comprehensive and tight contact with the sealing surface, further improving the sealing performance. At the same time, it avoids accelerated local aging of the sealing ring caused by excessive compression in one direction, extending the service life of the sealing ring.
[0036] In implementation, both the vertical annular surface 13 and the lower annular surface 14 of the annular step are provided with arc-shaped grooves 15, and the sealing ring contacts the arc-shaped grooves. The arc-shaped grooves provide curved surface support for the sealing ring. When the sealing ring is compressed, the arc-shaped grooves can accommodate its local deformation, making the stress distribution of the sealing ring more uniform and avoiding local wear or aging caused by stress concentration in traditional planar contact. At the same time, the contact area between the arc-shaped surface and the sealing ring is larger, and the reliability of the sealing contact is higher.
[0037] In implementation, several internally threaded cylinders 16 are fixedly installed downwards on the pump cover. The gland has through holes 17 that allow the internally threaded cylinders to pass through. The tension bolt 18 is threadedly connected to the internally threaded cylinders, and the end of the tension bolt abuts against the gland. The internally threaded cylinders at the lower end of the pump cover are inserted into the through holes. The tension bolt, through its threaded engagement with the internally threaded cylinders, generates an axial tension force on the pump cover and the gland, ensuring that the two fit evenly along the axial direction. The sealing ring only bears the axial pressure force, avoiding the sealing ring from bearing circumferential friction force, thus preventing the sealing ring from deforming or shifting at the source. At the same time, the tension force is controllable and evenly distributed, ensuring that the sealing ring and the sealing surface fit tightly and are subjected to consistent force, significantly reducing the risk of leakage.
[0038] In practice, it also includes a pressure ring 19, which is provided with an internal thread. An external threaded cylinder 20 that can be threadedly connected to the pressure ring is fixedly installed on the pressure cover. The pump cover is provided with a number of notches 21 at intervals around the circumference, and a protrusion 22 is formed between adjacent notches. The pressure ring is provided with a relief opening 23 facing the protrusion.
[0039] In this way, the pressure ring, through its threaded connection with the external threaded cylinder, generates an axial clamping force on the protrusion of the pump cover, ensuring a uniform circumferential fit between the pump cover and the pressure cap. The internal threaded cylinder is located below the protrusion. During installation, the position of the pressure ring is adjusted so that the protrusion of the pump cover aligns with the clearance opening and the internal threaded cylinder aligns with the through hole. The internal threaded cylinder is then inserted into the through hole, bringing the protrusion into contact with the pressure cap. Afterward, rotating the pressure ring achieves tightening. Throughout this process, the sealing ring primarily bears the axial clamping force, preventing it from bearing circumferential friction, thus preventing deformation and displacement, and ensuring a good sealing effect.
[0040] In practice, the pressure ring is provided with a threaded hole 24, and a clamping bolt 25 is connected in the threaded hole.
[0041] In this way, the clamping bolt can generate additional axial preload on the pressure ring, making up for any gaps that may exist in the threaded fit. This makes the clamping force of the pressure ring on the pump cover more sufficient and controllable, further enhancing the stability of the connection and preventing seal failure caused by loose threads during long-term use.
[0042] In practice, the outer side of the pressure ring is provided with several spaced-apart levers 26. The operator can easily apply rotational force through the levers, reducing the difficulty of installing or removing the pressure ring.
[0043] In summary, the drain pump of this dishwasher uses two sealing rings for double-layer sealing, combined with the irregular design of the annular groove to improve the sealing effect. At the same time, when the pump cover and the pressure cap are connected, a tension connection method is used, so the pump cover will not rotate relative to the sealing ring, avoiding the sealing ring from bearing the circumferential friction force of the pump cover, extending its service life, and the connection between the pump cover and the pressure cap is reliable and stable.
[0044] Finally, it should be noted that those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims and their equivalents, this utility model also intends to include these modifications and variations.
Claims
1. A drain pump for a dishwasher, comprising a pump body (1) and a pump cover (2), wherein a stator is provided on the pump body (1), a rotor is provided inside the pump body (1), a drive impeller is provided on the rotor, the drive impeller includes an impeller seat (3) fixedly connected to the rotor and an impeller blade (4) fixedly mounted on the impeller seat (3), a pressure cover (5) is fixedly mounted on the upper end of the pump body (1), the impeller seat (3) is located above the pressure cover (5), the rotor passes through the pressure cover (5) and is connected to the pressure cover (5) through a sealed bearing, the pump body (1) and the pump cover (2) form an impeller cavity, the drive impeller is located inside the impeller cavity, and the pump cover (2) is provided with an inlet and a outlet; characterized in that, The pressure cap (5) has an integrally formed boss (6) located below the impeller seat (3). The boss (6) has two annular steps (7) arranged around its circumference, and a sealing ring (8) is placed on each of the annular steps (7). The pump cover (2) has an annular groove (9) opposite the two annular steps (7), and the sealing ring (8) is located in the annular groove (9). The pump cover (2) is fixedly connected to the pressure cap (5).
2. The drain pump for a dishwasher according to claim 1, characterized in that, The annular groove (9) is composed of an upper flat annular surface (10), an inclined annular surface (11) and a side vertical annular surface (12) connected in sequence. The upper flat annular surface (10), the inclined annular surface (11) and the side vertical annular surface (12) are in contact with the sealing ring (8).
3. The drain pump for a dishwasher according to claim 1, characterized in that, The vertical ring surface (13) and the lower ring surface (14) of the annular step (7) are both provided with arc-shaped grooves (15), and the sealing ring (8) is in contact with the arc-shaped grooves (15).
4. The drain pump for a dishwasher according to claim 1, characterized in that, The pump cover (2) is fixedly mounted with several internally threaded cylinders (16) downwards. The pressure cover (5) is provided with a through hole (17) that allows the internally threaded cylinders (16) to pass through. The tension bolt (18) is threadedly connected to the internally threaded cylinders (16) and the end of the tension bolt (18) abuts against the pressure cover (5).
5. The drain pump for a dishwasher according to claim 1, characterized in that, It also includes a pressure ring (19), which is provided with an internal thread. An external threaded cylinder (20) that can be threadedly connected to the pressure ring (19) is fixedly installed on the pressure cover (5). The pump cover (2) is provided with a number of notches (21) spaced apart in the circumference. A protrusion (22) is formed between adjacent notches (21). The pressure ring (19) is provided with a relief opening (23) facing the protrusion (22).
6. A drain pump for a dishwasher according to claim 5, characterized in that, The pressure ring (19) is provided with a threaded hole (24), and a clamping bolt (25) is connected in the threaded hole (24).
7. A drain pump for a dishwasher according to claim 5, characterized in that, The outer side of the pressure ring (19) is provided with a number of spaced-apart paddles (26).