WO2022175472A1

WO2022175472A1 - Pump with multipart electronic housing

Info

Publication number: WO2022175472A1
Application number: PCT/EP2022/054118
Authority: WO
Inventors: David KRILL
Original assignee: KSB SE & Co. KGaA
Priority date: 2021-02-22
Filing date: 2022-02-18
Publication date: 2022-08-25
Also published as: EP4295049A1

Abstract

The invention relates to a pump, in particular a heating circulation pump, comprising at least one electronic housing for the pump electronics. The electronic housing is composed of at least two housing parts, and at least one seal element is inserted into the connecting gap between the at least two housing parts in order to seal the connecting gap between the housing parts from the surroundings. The invention is characterized in that at least one housing part has a skirt which protrudes beyond at least one section of the connecting gap and covers the connecting gap at least outwardly in some sections.

Description

description

Pump with multi-part electronics housing

The invention relates to a pump, in particular a centrifugal pump, with at least one electronics housing for the pump electronics, the electronics housing being composed of at least two housing parts and at least one sealing element being inserted in the connecting gap of the at least two housing parts in order to seal the connecting gap of the housing parts from the environment .

Such a centrifugal pump can be designed as a heating circulating pump. Modern heating circulating pumps are equipped with control logic for energy-efficient pump operation. In addition to a control module and any operating and display elements, this also includes a frequency converter for speed control of the pump drive. The electronics required for this are housed in an electronics housing that is attached to the circumference and/or the front of the pump motor.

During pump operation, the electronic components generate heat that has to be dissipated from the electronics housing to protect the components. A separate heat sink in the electronics housing ensures sufficient heat dissipation. For this reason, the electronics housing can also be designed in several parts, with part of the housing being formed by the metallic heat sink on which a plastic housing cover is placed. In general, such an electronic housing can also be composed of any desired housing parts. Since pumps, in particular centrifugal pumps or heating circulating pumps, are used to convey fluids, the electronics must be sealed off from the environment in order to prevent fluids from penetrating into the interior of the housing. For this reason, at least splash water protection according to IP44 is required for heating circulating pumps.

The problem is the interface between the housing parts and the resulting connection gap between the housing parts. One way to seal this gap is to use a simple sealing cord that is inserted into the gap between the housing parts. However, this requires a minimum available area in the contact area of the housing parts to support the sealing cord, which is associated with a certain minimum thickness of the housing wall. With this solution, an additional component in the form of the sealing cord must also be properly placed in the gap between the housing parts during the assembly process.

A simpler solution is therefore being sought to limit the number of components needed to assemble the pump. Furthermore, the solution is intended to place less stringent requirements on the geometry of the housing parts. All in all, a simple, inexpensive and safe solution should be found for Mondays.

This problem is solved by a pump according to the features of claim 1 . Advantageous refinements of the invention are the subject matter of the dependent claims.

According to the invention, it is proposed to form at least one housing part with an apron which protrudes beyond at least a section of the connecting gap of the two housing parts after the housing parts have been joined together. The apron covers the gap on the outside of the electronics housing and thus serves as a kind of protective shield for the connection gap against external influences such as spray water. This additional protective measure makes it possible to construct the sealing element used in the connecting gap in a simpler way. The pump can preferably be designed as a centrifugal pump, particularly preferably as a heating circulation pump.

The apron is preferably formed by a side wall of the at least one housing part that protrudes beyond the connecting gap and at the same time overlaps the adjacent side wall of the other housing part. The connecting gap is formed by an edge formed on the inside of the side wall, in particular a peripheral edge, which lies opposite an opposite edge of the other housing part during assembly.

According to an advantageous embodiment, it can be provided that the at least one sealing element consists of or comprises a compressible sealing material. The sealing element is applied to an edge of at least one housing part that forms the connecting gap. When assembling the housing parts, the sealing element is compressed by a compression edge of the other housing part. The compression edge is preferably part of the housing part having the skirt and the sealing element is applied to the other housing part.

An essential point of the invention is that the sealing element is applied to its sealing seat before the final assembly of the electronics housing. This reduces the number of components to be assembled during the assembly process. Ideally, the sealing element is already applied during the manufacture of the at least one housing part.

It makes sense for the sealing element to be applied around the entire edge of the housing part in order to seal off the connection gap over the entire housing circumference. The edge of the housing part can be provided with a groove, which serves as a sealing seat for fixing the sealing element.

If the sealing element is applied to the edge all the way around the housing circumference, this preferably also applies to the shaping of the compression edge. The compression edge can be in the form of a lip running around the inside of the side wall of the housing part.

It can be particularly advantageous if the housing wall of the at least one housing part that forms the connecting gap has a bevel. In the installed position of the pump, the incline of the housing wall on the outside of the electronics housing is inclined to the horizontal. The slope is oriented in such a way that there is a gradient away from the connecting gap when the pump is installed. As a result, a quantity of liquid that has accumulated in the region or in the vicinity of the connecting gap is diverted or carried away due to the force of weight.

Such a bevel can be a draft bevel of the housing part, as is often required in the production of castings.

According to a possible advantageous embodiment, the sealing element can be a foam seal. Such a seal can preferably be applied as a pasty mass to the edge of one housing part before the housing parts are joined together, in particular injected into the seat of the seal, preferably the groove. This process of applying the mass can expediently already take place during the manufacture of the housing part. Such a seal is also known as a FIPGH seal (formed-in-place-foam-gasket).

As an alternative to the form of seal described above, it is also conceivable to form the sealing element from at least two components. Such a two-component seal comprises, for example, at least one elastic element that achieves the desired sealing effect through compression. In particular, it is provided that the elastic component lies at least partially in the area of the connecting gap in order to achieve the desired sealing of the gap.

The at least one second component can instead consist of a non-elastic material or at least a significantly less elastic material. This component, hereinafter referred to as the rigid or rigid component, is adjacent to the elastic Component and serves to stabilize the elastic component, preferably to stabilize the shape and / or position of the elastic component, especially during the assembly process of the pump, ie before or during the assembly of the housing parts.

The rigid component can be designed as a stabilizing frame which is applied to an edge of at least one housing part that forms the connecting gap. The elastic component can be placed directly on top of the rigid component.

It is conceivable that a surface of the rigid component is provided with one or more depressions, in particular openings, ideally bores, for receiving the elastic component. The elastic component has corresponding elevations and/or projections which engage in the depressions or penetrate the openings when the components are assembled. As a result, an additional positional fixation of the elastic component on the rigid component is achieved.

The sealing element, preferably the elastic component, particularly preferably a molded sealing lip of the elastic component, is compressed in the radial direction by the apron when the housing parts are put together. In the radial direction means that the sealing element is compressed from the outer circumference of the housing in the direction of the interior of the housing, i.e. transversely to the direction in which the two housing parts are joined. The compressed lip of the resilient component preferably lies between an outer perimeter of the heat sink and the inner wall of the skirt. In this case, a sealing effect is already achieved in the skirt area, i.e. between the outer surface of one housing part and the inner surface of the skirt of the other housing part.

The radial thickness of the seal, in particular of the sealing lip, can be compressed by 50% to 80%, in particular by 60% to 70%. In particular, can also be provided that the ratio between gap thickness and seal thickness in Be rich between 0.5 to 0.85, preferably between 0.6 and 0.75.

The elastic component can be a thermoplastic elastomer (TPE), in particular a thermoplastic polyurethane (TPU). The rigid component can be or comprise a stable polymer, in particular PA6.

The at least two housing parts can consist of identical or different materials. It is conceivable that a first housing part is made of plastic while the other housing part is made of metal, in particular aluminum. In one embodiment, the at least one housing part, in particular the housing part made of metal, preferably aluminum, can be a heat sink for dissipating the heat loss produced by the electronics from the electronics housing. In particular, the heat sink forms part of the electronics housing wall. The other part of the housing can be a plastic cover that is placed on the heat sink. The sealing element is preferably applied to an edge of the heat sink, while the plastic housing part is equipped with the skirt and in particular the compression edge.

In an advantageous embodiment of the pump, at least one first electronic circuit board of the pump can be installed in the heat sink, ie it can be stored there. The side walls of the heat sink completely encircle the circumference of the electronics board. This electronics board can be the main board, which is equipped, for example, with the necessary power electronics for pump control. At least one second electronic circuit board can be placed on the first electronic circuit board with a defined spacing. The perimeter of the second electronics board is completely surrounded by the side walls of the assembled plastic cover. As a result, the connection gap is located in an area of the housing parts that is at a level between the two electronic circuit boards. The second electronic circuit board includes, for example, necessary components for realizing an operating interface of the pump. Further advantages and properties of the invention are to be explained below with reference to an exemplary embodiment illustrated in the figures. Show it:

Figure 1: a perspective side view of the pump according to the invention in the form of a circulation pump,

Fig. 2a: a plan view of the front side of the pump

Fig. 2b: a sectional view along the section axis A-A from Figure 2a through the electronics housing with a first embodiment of the sealing element,

FIG. 3: a detailed view of the area of the contact point between the plastic and heat sink housing marked as D in FIG. 2 with an integrated FIPFG seal,

Fig. 4: a view of the housing edge of a housing part of the pump according to

Figures 1, 2a with an alternative embodiment of the sealing element,

Fig. 5: a sectional view of the housing edge of the pump according to Figure 4 and

Fig. 6: a further sectional view of the pump according to Figures 4, 5 with together quantity set housing.

FIG. 1 shows a perspective side view of the pump according to the invention, which in the exemplary embodiment is designed as a circulation pump by way of example. This consists of a hydraulic part, not shown here, and the Antriebsaggre gat, which consists of the electric motor 3 for driving the pump, and an electronics housing 2. The electronics housing 2 is composed of a plastic housing part 4 and a heat sink 5 made of aluminum, with the heat sink 5 forming the bottom of the electronics housing 2 by means of which the electronics housing 2 is mounted axially on the motor 3 . The electronics housing 2 also extends in the radial direction of the electric motor 3. The local area of the heat sink 5 is designed with a large number of cooling fins 6. The electronics housing 2 must be protected against the ingress of water. In particular, splash protection according to IP44 is required for heating pumps. Critical is the interface between the heat sink 5 and the plastic housing part 4 of the electronics housing 2, which must be sealed from the outside by special measures. This is where the solution according to the invention comes in, which is to be explained below with the aid of sectional illustrations along the section axis AA.

FIG. 2a shows the electronics housing 2 from a rear view of the pump. Figure 2b is a sectional view along the cutting axis A-A and provides an insight into the inside of the electronics housing 2. Figure 3 shows a detail D of the gap between the housing parts 4, 5. The electronics main circuit board 7 of the heating pump is installed in the aluminum heat sink 5 , whose side walls 5a surrounded the board 7 itself closed ge. A second electronic circuit board 8 is installed within the housing 4 Kunststoffge and placed on the main circuit board 7 at a distance. The resulting connection gap between the plastic and aluminum housing 4, 5 must be sealed against splashing water.

For this purpose, a FIPFG seal 10 (formed-in-place-foam-gasket) is applied to the edge 5b of the side wall 5a of the aluminum heat sink 5, which is thus part of the heat sink assembly 5. No additional assembly step is required in pump production. In particular, the seal 10 is already injected during the manufacture of the aluminum cooling body 5 in a circumferential groove 5c along the edge 5b as a seal seat in the form of a pasty mass. The seal 10 thus runs on the edge 5b over the entire, defined by the side walls 5a of the heat sink 5 To catch.

About the heat sink, the plastic housing 4 is set, which has a wall 5 a of the heat sink 5 overlapping apron 9, the sides. At the level of the foam seal 10 there is a lip 11 on the inner wall of the skirt 9 which runs around the inner circumference of the plastic housing 4 and which presses into the foam seal 10 when the housing parts 4, 5 are assembled. That impressive lip 11 produces the compression of the sealing foam 10 required to seal the gap.

Since only a slight compression of the sealing foam 10 is produced by the lip 11, the sealing point must also be protected against splashing water, which is achieved by the apron 9 of the plastic housing 4. The main part of the splashing water is already kept from the seal 10 by the apron 9 . A defined installation position of the pump and the necessary draft angles of the heat sink in the area of the side walls 5a result in a slope of the side walls relative to the horizontal, as a result of which the water is guided away from the sealing point 10. Splash water that nevertheless reaches the foam seal 10 is then prevented from penetrating into the housing 2 by the compressed foam seal 10 .

The main advantage of the invention is that no additional sealing components have to be installed during the assembly process of the pump or the electronics housing 2 since the foam seal 10 is already part of the heat sink 5 . It is also possible to manufacture the plastic housing 4 with a reduced wall thickness, which means that the manufacturing costs of the pump can be reduced.

FIGS. 4 to 6 show the pump according to the invention with an alternative embodiment of the sealing element (100).

FIG. 4 shows a plan view of the open side of the heat sink 5 on which the plastic housing 4 is placed. In contrast to the embodiment of Figu ren 2b, 3, the edge 5b of the side wall of the heat sink has no groove, but is instead provided with a shoulder 5d. In the exemplary embodiment shown in FIGS. 4-6, a two-component seal 100 is applied to the peripheral edge 5b of the side wall 5a of the aluminum body 5. The seal 100 consists of an elastic component 110 which is or comprises a thermoplastic elastomer (TPE). In particular, a thermoplastic polyurethane (TPU) is used. A dimensionally stable material is used for the second component 120, for example a is or comprises a stable polymer. In particular, the component 120 can consist of PA6.

The elastic component 110 is thereby when the housing parts 4,

5 compressed to thereby achieve the required sealing effect to seal the gap between the housing parts. The rigid component 120 instead serves as a stabilizing frame for receiving the elastic component during assembly of the electronics housing 2, whereby the elastic component 110 can be stabilized both in its shape and in its position on the edge 5b of the heat sink 5 during the assembly process. It can be seen in FIG. 4 that both the elastic component 110 and the rigid component 120 run over the entire peripheral edge 5b of the heat sink 5.

FIG. 5 shows a sectional view of the heat sink 5 shown in FIG. 4 with the applied two-component seal 100. The side wall 5a of the heat sink 5 can be seen here, on the upper edge 5b of which the elastic component 110 is placed circumferentially. It can also be seen that the edge 5b includes a stepped shoulder 5d, which is completely occupied by the elastic component 110. FIG. In the area of the heel, the elastic component 110 also includes a radially outwardly directed sealing lip 111, which is pressed and compressed in the radial direction against the rear wall of the step 5d by the skirt of the housing part 4 when the housing parts 4, 5 are joined together. This can be seen in FIG. 6, which shows a corresponding sectional view with the housing part 4 fitted.

In the figures 5, 6 can also be seen that the rigid sealing component

120 several, preferably evenly spaced openings over the circumference

121 has. Corresponding projections 112 of the elastic sealing component 110 engage in these openings 121 and thereby ensure improved position stabilization. It can also be seen in FIGS. 5, 6 that the elastic sealing component 110 does not completely cover the upper side of the rigid sealing component 120, but only protrudes up to half of the component 120 in the radial direction. Instead, the elastic sealing component 110 protrudes beyond the radially outward ßenliegend edge of the component 120 and runs angled in the direction of the Stu fenabsatzes 5d of the heat sink 5. As a result, the radially outer part of the rigid component 120 is surrounded by the elastic component 110.

Claims

Claims Pump with multi-part electronics housing

1. Pump, preferably a centrifugal pump, particularly preferably a heating circulating pump, with at least one electronics housing (2) for the pump electronics (7, 8), where the electronics housing (2) is composed of at least two housing parts (4, 5) and in the connecting gap the at least two housing parts (4, 5) at least one sealing element (10, 100) is used to seal the connection gap of the housing parts (4, 5) from the environment, characterized in that at least one housing part (4) has at least one section apron (9) protruding from the connecting gap and covering the connecting gap at least in sections on the outside.

2. Pump according to Claim 1, characterized in that the at least one sealing element (10) consists of or comprises a compressible sealing material and is applied to an edge (5b) forming the connecting gap of at least one housing part (5), the sealing element (10) is compressed when assembling the housing parts (4, 5) by a compression edge (11) of the other housing part (4).

3. Pump according to Claim 2, characterized in that the sealing element (10) is applied circumferentially over the entire edge (5b) of the housing part (5), the edge (5b) of the housing part (5) preferably having a groove (5c) is provided as a sealing seat, in which the sealing element (10) is introduced.

4. Pump according to one of the preceding claims 2 or 3, characterized in that the compression edge (11) over the entire circumference of the side wall of the other housing part (4) is formed, in particular in the form of a circumferential lip (11).

5. Pump according to one of the preceding claims, characterized in that the housing wall (5a) having the edge (5b) has a bevel which, in the installed position of the pump, has a gradient relative to the horizontal away from the connection gap in order to prevent weight-related detachment or to convey away a quantity of liquid which has accumulated around the region of the connecting gap.

6. Pump according to claim 5, characterized in that the bevel is a draft angle of the housing part (5) produced by casting.

7. Pump according to one of the preceding claims 2 to 6, characterized in that the at least one sealing element (10) is a foam seal, which is preferably applied as a pasty mass to the edge (5b) of one housing part (5) before the housing parts are joined together (4, 5), ideally during the manufacture of the housing part (5), was applied.

8. Pump according to claim 1, characterized in that the at least one sealing element (100) is a 2-component sealing element, in particular consisting of an elastic component (110) and a rigid component (120).

9. Pump according to claim 8, characterized in that the rigid component (120) forms a stabilizing frame on a the connection gap forming edge (5b) of at least one housing part (5), in particular on a stepped shoulder formed there, wherein the elastic component (110) is accommodated by the rigid component (120) and its shape and/or position is stabilized.

10. Pump according to one of claims 8 or 9, characterized in that the sealing element (100), in particular a molded lip (111) of the elastic's component (110), is compressed in the radial direction by the skirt (9), in particular a Compression of the lip thickness of the elastic component (110) is provided by 50% to 80%, in particular by 60% to 70%.

11. Pump according to claim 10, characterized in that the compressed lip (111) of the elastic component (110) between an outer circumference of the heat sink (5), in particular the step-like shoulder (5d), and the inner wall of the skirt (9 ) lies.

12. Pump according to one of claims 8 to 11, characterized in that the elastic component (110) is a thermoplastic elastomer (TPE), in particular a thermoplastic polyurethane (TPU), and/or the rigid component (120) is a stable polymer , in particular PA6.

13. Pump according to one of the preceding claims, characterized in that the housing parts (4, 5) consist of different types of material, for example metal and plastic.

14. Pump according to one of the preceding claims, characterized in that one housing part is a heat sink (5) made of metal and the other housing part is a plastic cover (4).

15. Pump according to claim 14, characterized in that at least a first

Electronic circuit board (7) of the pump, in particular the main circuit board of the pump, in the heat sink (5) is installed and the side walls (5a) of the heat sink (5) surround the electronic circuit board (7) closed, preferably at least one second electronic circuit board (8) is placed on the first electronic circuit board (7), and the circumference of the second electronic circuit board (8) is completely surrounded by the side walls of the assembled plastic cover (4), and the connection gap of the housing parts (4, 5) at a level between the two Elektronikplati nen (7, 8) is.