WO2024256211A1

WO2024256211A1 - Pump device

Info

Publication number: WO2024256211A1
Application number: PCT/EP2024/065280
Authority: WO
Inventors: Koorosh BORDBAR
Original assignee: Grundfos Holdings AS
Current assignee: Grundfos Holdings AS
Priority date: 2023-06-14
Filing date: 2024-06-04
Publication date: 2024-12-19
Anticipated expiration: 2025-12-14
Also published as: CN121336048A; EP4728199A1

Abstract

The invention refers to a pump device comprising at least a first housing part (4) and a second housing part (6) with a sealing means arranged between the first (4)and the second housing part (6), wherein the sealing means comprises a sealing ring (8) having a rigid support element ( 10) and an elastic sealing layer ( 12) covering the support element (10) on at least one surface section, which at least one surface section is in contact with the first (4) and the second housing part (6).

Description

[01 ] The invention refers to a pump device comprising at least a first housing part and a second housing part.

[02] Pump devices usually comprise a pump, an electric drive motor and an electronics housing containing control electronics and/or electrical connections of the pump device. A pump device may comprise further housing parts. Regardless of possible shaft seals, usually sealing elements are arranged between the different housing parts to in particularseal the interior spaces containing electric or electronic components towards the environment. For example it is known to have a sealing between an electronics housing and the motor housing. The sealing may be an elastic sealing ring. Alternatively, it is known to have elastic sealing elements directly integrated into a plastic housing structure, for example by two component injection molding. Such integration of sealing elements into the plastic structure of the housing requires expensive tools and molding machines.

[03] In view of this, it is the object of the invention to provide a pump device offering a secure sealing between two housing parts, which is easy to assemble.

[04] This object is achieved by a pump device having the features defined in claim 1 . Preferred embodiments are defined in the subclaims, the following description and the accompanying drawings. [05] The pump device according to the invention comprises at least a first housing part and a second housing part with a sealing means arranged between the first and the second housing part. These housing parts preferably each define a separate interior space housing different electrical and/or electronic components. The sealing means is configured to act between the two fixed housing parts only, i.e. it is a sealing means being free of shaft-feedthroughs. This means, the sealing means is without any shaft sealing functionality. The sealing means preferably is arranged to seal the interior of the two housing parts towards the surroundings. For example, the interior of the housing parts may be sealed towards the outside to avoid water or moisture entering the interior of the housing parts. As mentioned above, the two housing parts may define separate interior spaces for containing electrical or electronic components with an interface region between these two housing parts. In the interface region between the two housing parts there may be provided openings, for example for electric connections between electric or electronic components arranged inside the two housing parts, i.e. preferably inside the separate interior spaces defined by the two housing parts.

[06] According to the invention the sealing means comprises a sealing ring having a rigid support element and an elastic sealing layer covering the support element on at least one surface section. This at least one surface section is in contact with the first and the second housing part. The elastic sealing layer seals a contact region between the two housing parts. The sealing layer is in contact with both housing parts and providing a ring-shaped structure with a closed surface between both housing parts such that the gap or contact region between both housing parts is completely closed by the elastic sealing layer. Thus, the elastic sealing layer provides the actual sealing functionality of the sealing means. The support element ensures a form stability of the sealing ring simplifying the assembling of the sealing means with a first housing part and/or the second housing part. Preferably the rigid support element is ring-shaped to provide a desired shape or form of the sealing ring corresponding to the contact surfaces of the at least one first housing part and the at least one second housing part. The combination of a rigid support element and an elastic sealing layer allows to provide a separate sealing means not being integrated into one of the housing parts. This allows the use of same sealing ring for different housing parts. The rigid support element provides a form stability of the entire sealing ring which is beneficial during the assembling process. The assembling process is simplified. Furthermore, the rigid structure helps to ensure the correct positioning of the sealing ring on the two housing parts ensuring the desired sealing properties.

[07] Preferably the support element is of circular shape. By this, it defines a rigid sealing ring structure of circular shape. Nevertheless, the shape may be different, depending on the shape of the housing parts to be sealed.

[08] According to a preferred embodiment the support elements is made from plastic, preferably by injection molding. The plastic may be a thermoplastic material providing sufficient stiffness to ensure the form stability of the support element. Injection molding allows a cheap mass production of the support element.

[09] The elastic sealing layer in a possible embodiment is made from an elastomeric material, preferably rubber or a thermoplastic elastomeric material. Preferably the sealing layer is produced by injection molding. Injection molding allows a cost-effective mass production of the sealing layer having a complex shape, i.e. a shape differing from a simple o-ring design. Preferably the sealing layer has a shape of a closed ring as explained above to completely seal a gap between the first and the second housing part in the contact region of the two housing parts. The support element and the sealing layer may be produced separately and connected afterwards, for example by a form-fit, a force-fit and/or a material-fit. The material-fit may be a welding or for example a gluing connection.

[10] In a further possible embodiment, the support element and the sealing layer may be produced by a two-component injection molding process. This means, the sealing layer and the support element may be connected via an injection molding process forming an integral part comprising the support element and the elastic sealing layer. By the injection molding the sealing layer is connected firmly and durably to the support element.

[1 1 ] The sealing layer preferably is arranged on at least one axial surface of the support element and preferably on two opposite axial surfaces of the support element. The at least one axial surface of the support element preferable is an axial surface facing one of the housing parts, i.e. the at least one first housing part or the at least one second housing part. Thus, the sealing layer is arranged between the axial surface of the support element and a surface of the housing part such that the sealing layer may be pressed against a sealing surface of the housing part by the support element. The support element ensures the secure contact of the sealing layer at one of the housing parts. In a further possible embodiment the sealing layer may be in contact with two axial ends or axial surfaces of the support element, the two axial surfaces facing the two housing parts. In such an arrangement the sealing layer may provide a sealing contact in axial direction with both of the housing parts.

[12] In a further possible embodiment, the sealing layer is arranged on at least one circumferential surface of the support element connecting the two axial surfaces or two axial surfaces of the support element or two axial ends of the support element, respectively. This arrangement may provide a closed sealing surface between the first housing part and the second housing port. Furthermore, this arrangement may provide a sealing surface on the circumferential surface allowing a sealing in a radial direction. The sealing layer on the circumferential surface may come into contact with a corresponding circumferential sealing surface on one of the housing parts. Preferably the sealing layer is arranged on an inner circumferential surface of a ring-shaped support element. Such a sealing layer on the inner circumferential surface may come into contact with a sealing surface on an outer circumference of one of the housing parts. For example, the first or the second housing part may engage the inner circumference of the sealing ring coming into contact with a sealing layer on the inner circumference of the support element.

[13] In a special embodiment the sealing ring has a sealing layer providing at least one sealing surface on an axial end side and at least one sealing surface on a circumferential surface, for example the inner circumferential surface. This allows to seal against one of the housing parts in axial direction whereas the seal is in contact with the other housing part in a radial direction.

[14] In a further possible embodiment, the sealing ring is connected to one of the first or the second housing part by a force-fit and/or a formfit. This allows to preassemble the sealing ring on one of the housing parts prior to assembling the two housing parts. For example, there may be provided engagement hooks or protrusions on one of the housing parts to fix or encompass the sealing ring, in particular the support element of the sealing ring.

[15] In a further possible embodiment, the first housing part may be an electronics housing comprising for example control electronics of the pump device. Thus, the control electronics can be arranged inside a first interior space defined by the first housing part. The second housing part may be a motor housing to which the electronics housing is attached. The second housing port thereby preferably defines a second interior space containing an electric motor. Between both the electronics housing and the motor housing there may extend electrical connections connecting the motor and the control electronics. For these connections there may be openings in the first and the second housing parts, opening towards the interior spaces defined by the two housing parts.. The gap between the first and the second housing part or contact region between the first and the second housing part, respectively, is sealed by the sealing means or sealing ring as described before. Nevertheless, the sealing means may be arranged between other housing parts of a pump device in similar manner.

[16] In the following, the invention is described byway of example with reference to the accompanying drawings. In these:

Figure 1 schematically shows a pump device,

Figure 2 schematically shows an exploded view of a second housing part and a sealing ring,

Figure 3 shows a schematic cross section of the second housing part with the attached sealing ring,

Figure 4 shows an enlarged view of detail IV in figure 3, and

Figure 5 shows a detail of a cross section of a first housing part and a second housing part with a sealing ring arranged therebetween.

[17] The pump device according to this example comprises a pump housing 2 with an attached motor housing 4 containing an electric drive motor. The motor housing 4 defines a first interior space containing the electric drive motor. Furthermore, the pump device comprises an electronics housing 6 which is attached to the motor housing 4. In this example the electronics housing 6 is attached to the axial end side of the motor housing 4. The electronics housing 6 defines an interior space for electronic components. The electronics housing 6 may contain control electronics of the pump device. The motor housing 4 forms a first housing part, whereas the electronics housing 6 forms a second housing part with a sealing means arranged therebetween. The sealing means is free of shaft-feedthroughs and only acting between the fixed housing parts.

[18] The sealing means comprises a sealing ring 8. In this example the sealing ring 8 is of circular shape. However, depending on the shape of the housings the sealing ring 8 may be of different shape, too.

[19] The sealing ring 8 comprises a rigid support element 10 with an elastic sealing layer 12 attached to the support element 10 or partly covering the support element, respectively. In this example the sealing layer 12 is arranged on the inner circumference of the ring-shaped support element 10 and partly covering one axial end side of the support element 10. Furthermore, the support element 10 comprises a plurality of openings 14 extending in radial direction through the support element 10. The sealing layer 10 engages into these openings 14, which are distributed over the entire circumference of the support element 10. Furthermore, the sealing layer 12 on the inner circumference of the support element 10 forms a circular collar 16 facing the electronics housing 6 and coming into sealing contact with a ring-shaped sealing surface 18 on the electronics housing 6. The sealing surface 18 protrudes from an inner surface of a receptacle 20 on the electronics housing 6 into which the sealing ring 8 is inserted. On the axial end side of the receptacle 20 there are arranged hooks 22 extending in a radial direction from the inner wall of the receptacle 20. The hooks 22 engage with the axial end side of the sealing ring 8 when inserted into the receptacle 20. Thus, the hooks 22 provide a snap fit for fixing the sealing ring 8 in the receptacle 20.

[20] Figure 4 shows the sealing ring 8 inserted into the receptacle 20 of the electronics housing 6, i.e. inserted into the second housing part. As can be seen, the collar or shoulder 16 of the sealing layer 12 is in sealing contact with the sealing surface 18 on the electronics housing 6. Thus, there is a sealing in axial direction between the sealing ring 8 and the electronics housing 6. On the opposite axial end of the sealing ring 8 the elastic sealing layer partly extends along the axial end side or surface of the support element 10. However, the radial outer portion of the axial end surface is not covered by the sealing layer 12. In this radial outer portion the hooks or engagement hooks 22 are in contact with the sealing ring 8 to fix the sealing ring 8 inside the receptacle 20. Furthermore, in figure 4 it can be seen that the sealing layer 12 extends into the openings 14 provided in the support element 10, i.e. extend through the openings 14 in radial direction.

[21 ] Preferably the elastic sealing layer 12 is made from an elastomeric material attached to the support element 10 by a two-component injection molding process. The support element 10 may be formed from a thermoplastic material, preferably by injection molding, too. As can be seen in figure 4 the sealing ring 8 is fixed in the receptacle 20 in axial direction between the sealing surface 18 and the hooks 22. The elastic sealing layer is dimensioned such that there is a press fit between the hooks 22 and the sealing surface 18 ensuring a secure sealing contact between the shoulder or collar 16 and the sealing surface 18. There is a pressure in axial direction provided by elastic deformation of the sealing layer, i.e. the part of the sealing layer 12 protruding on the inner circumference of the support element 10 and forming the collar or shoulder 16. [22] On the inner circumference the sealing layer 12 has a ring-shaped projection 24 forming a ring-shaped sealing projection coming into contact with the first housing part, i.e. the motor housing 4 as shown in figure 5. To achieve a pressure in radial direction the sealing projection 24 has a dimension such that it is elastically deformed when coming into contact with the outer circumferential wall of the motor housing 4.

[23] As can be seen in figure 5 there is a sealing contact in radial direction between the sealing layer 12 and the motor housing 4 by contact of the projection 24, whereas there is a sealing contact in axial direction between the collar 16 and the sealing surface 18 of the electronics housing 6.

List of reference numerals

2 pump housing

4 motor housing

6 electronics housing 8 sealing ring

10 support element

12 sealing layer

14 openings

16 collar, shoulder 18 sealing surface

20 receptacle

22 hooks

24 projection

Claims

1 . Pump device comprising at least a first housing part (4) and a second housing part (6) with a sealing means arranged between the first (4) and the second housing part (6), characterized in that the sealing means comprises a sealing ring (8) having a rigid support element (10) and an elastic sealing layer (12) covering the support element (10) on at least one surface section, which at least one surface section is in contact with the first (4) and the second housing part (6).

2. Pump device according to claim 1 , characterized in that the support element (10) is ring-shaped and preferably circular.

3. Pump device according to claim 1 or 2, characterized in that the support element (10) is made from plastic, preferably by injection molding.

4. Pump device according to one of the preceding claims, characterized in that the elastic sealing layer (12) is made from an elastomeric material, preferably by injection molding.

5. Pump device according to one of the preceding claims, characterized in that the support element (10) and the sealing layer (12) are produced separately and connected by a form-fit, a force-fit and/or a material-fit.

6. Pump device according to one of the preceding claims, characterized in that the support element (10) and the sealing layer ( 12) a produced by a two-component injection molding process.

7. Pump device according to one of the preceding claims, characterized in that the sealing layer (12) is arranged on at least one axial surface of the support element ( 10) and preferably on two opposite axial surfaces of the support element (10).

8. Pump device according to one of the preceding claims, characterized in that the sealing layer (12) is arranged on at least one circumferential surface of the support element (10) connecting two axial surfaces of the support element (10), preferably an inner circumferential surface of a ring-shaped support element (10).

9. Pump device according to one of the preceding claims, characterized in that the sealing ring (8) is connected to one of the first (4) or second housing part (6) by a force-fit and/or a form-fit.

10. Pump device according to one of the preceding claims, characterized in that the first housing part (4) is an electronics housing (6) and the second housing part (6) is a motor housing (4).