DE102023207408A1 - Fluid pump, motor vehicle, manufacturing method for such a fluid pump and use of such a fluid pump in a heat transport medium circuit - Google Patents

Abstract

A fluid pump (2) is proposed, in particular for a motor vehicle, which has a pump stage (10), an electric motor (4) for driving the pump stage (10) and an electronic assembly with a printed circuit board (24) with electronic components (26) arranged thereon.
The electronic assembly and a stator (6) of the electric motor (4) are enclosed by a plastic housing (20) of the fluid pump (2) and are arranged and spaced apart from one another by the plastic housing (20) in such a way that the electronic assembly and/or the stator (6) are thermally connected in regions directly and/or indirectly via the plastic housing (20) and without an air gap to a fluid chamber (22) of the plastic housing, via which a fluid that can be conveyed via the pump stage (10) circulates.
Furthermore, a vehicle with such a fluid pump, a manufacturing method for such a fluid pump and a use of such a fluid pump in a heat transport medium circuit are proposed.

Description

The invention relates to a fluid pump, in particular for a motor vehicle, a motor vehicle with such a fluid pump, a manufacturing method for such a fluid pump and a use of such a fluid pump in a heat transport medium circuit or a heat transport medium circuit system, in particular of a motor vehicle.

In particular, in the case of cooling water pumps used in motor vehicles, electrical circuit boards of such cooling water pumps can be exposed to high thermal loads from the environment and/or from waste heat from electrical components arranged on the circuit board, so that the performance and/or service life of such circuit boards can be impaired in the case of purely convective cooling by ambient air.

The object of the present invention is to provide an improved fluid pump. A further object of the present invention is to simplify a fluid pump.

This object is achieved by a fluid pump with the features of claim 1. Claims 8, 9 and 15 protect a motor vehicle with such a fluid pump or a method for producing such a fluid pump or a use of such a fluid pump in a heat transport medium circuit. The subclaims relate to advantageous further developments.

A fluid pump is proposed, in particular for a motor vehicle, which has a pump stage, an electric motor for driving the pump stage and an electronic assembly - for controlling the electric motor - with a printed circuit board with electronic components arranged on it.

The electronic assembly and a stator of the electric motor are enclosed or surrounded by a plastic housing of the fluid pump and arranged in relation to one another in such a way that the electronic assembly and/or the stator are thermally connected in regions directly and/or indirectly via the plastic housing - or a plastic housing section - and thereby free of an air gap - or free of an air gap - to a fluid space of the plastic housing, via which a fluid that can be conveyed via the pump stage circulates.

The proposed fluid pump advantageously makes it possible to save on components in the form of a can or canister, in the form of at least one sealing ring and in the form of fastening elements in the form of screws, which are known to separate an electronic assembly and a stator of the type described above from a cooling medium in the form of a fluid. By eliminating the can or canister, which is known to separate a dry area of the stator from a wet area of a rotor of the electric motor, a previously known air gap between the stator and the can or canister is also eliminated.

And as a result of the direct and/or air-gap-free indirect thermal connection of the stator to this fluid, the electric motor can be cooled and thus operated more efficiently.

In one embodiment, the fluid pump conveys a cooling liquid, such as a water-based cooling liquid mixture or, in the simplest case, just water, or is intended for this purpose, in particular designed or used for this purpose. It can therefore in particular be an (electric) cooling water pump.

In one embodiment, a plastic partition is formed between the circuit board and the fluid chamber, which separates the circuit board and thus the electronic assembly - the electric motor or the fluid pump - from the fluid chamber at least partially and in another embodiment even completely. This partition can be designed or formed to be only a few millimeters or even just a few tenths of a millimeter thick, at least in sections.

In addition or as an alternative to this, in a further embodiment, a plastic partition wall is formed between the stator and the fluid space, which separates the stator from the fluid space at least partially and in a further embodiment even completely. This partition wall can also - analogous to what was previously stated - be designed or formed to be only a few millimeters or even just a few tenths of a millimeter thick, at least in sections.

It is proposed to arrange the electronic components on a side of the circuit board facing away from the fluid space. This allows the circuit board to be thermally connected to the fluid space of the plastic housing directly or indirectly via the plastic partition wall, which is formed with thin walls in sections, at least in sections. The plastic partition wall can be formed at least in sections with the smallest possible wall thickness on the side of the circuit board facing the fluid space in the With a view to achieving the best possible thermal connection, this plastic partition wall - as already mentioned - can be designed or formed to be only a few millimetres or even just a few tenths of a millimetre thick, at least in sections.

In a further embodiment, it is proposed that the plastic housing - for example made of a thermosetting material - is also molded onto or formed at least in sections onto a pump stage housing or pump stage housing part made of a plastic - for example made of a thermoplastic material. Such a material bond or such a material bond makes it possible to save on further sealing and/or connecting components - for example in the form of sealing rings and screws etc. - which are known to serve to fluidically separate a stator of the type described above from a pump stage housing of the type described above and thereby seal the stator against a pumpable fluid and/or connect the stator to the pump stage housing.

Furthermore, a motor vehicle or vehicle with at least one fluid pump of the type described above is proposed.

A method for producing a fluid pump of the type described above is also proposed, in which, in order to form a plastic housing of the fluid pump, an arrangement of at least one stator of an electric motor - for driving a pump stage - and an electronic assembly - for controlling the electric motor - with a circuit board with electronic components arranged on it is overmolded with a plastic in such a way that the stator and the electronic assembly are fixed to one another in such a way that the electronic assembly and / or the stator are thermally connected in regions directly and / or indirectly via the plastic housing - or a plastic housing section - and thereby without an air gap - or free of an air gap - to a fluid space of the plastic housing, which is formed during the plastic overmold, via which a fluid that can be conveyed via the pump stage circulates.

It is proposed that a plastic partition be formed between the circuit board and the fluid space, which separates the electronic assembly from the fluid space at least partially and, in another embodiment, even completely. This partition can be designed or formed to be only a few millimeters or even just a few tenths of a millimeter thick, at least in sections.

In addition or as an alternative to this, it is proposed that a plastic partition wall be formed between the stator and the fluid space, which separates the stator from the fluid space at least partially and, in another embodiment, even completely. This partition wall can also be designed or formed to be only a few millimeters or even just a few tenths of a millimeter thick, at least in sections.

It is also proposed that the electronic components be arranged on a side of the circuit board facing away from the fluid space. Reference is made here to the advantages in this regard already described above.

It is further proposed that the plastic housing is also molded onto a pump stage housing at least in sections. Reference is made here to the advantages in this regard already described above.

It is further proposed to use a fluid pump of the type described above in a heat transport medium circuit, in particular of a motor vehicle.

• 1: eine Fluidpumpe mit einer vorgeschlagenen Kunststoffgehäuseausführung.

Further advantages and features emerge from the subclaims and the embodiments. The only schematically shows:

• 1 : a fluid pump with a proposed plastic housing design.

The proposed fluid pump design or fluid pump 2 is shown in an axial section and has a plastic housing 20 made of, for example, an injection-molded or cast thermosetting plastic or material, for example in the form of an epoxy resin, which encloses or encompasses an electronic assembly with a circuit board 24 with electronic components 26 arranged on it and a socket 28 for electrically contacting the circuit board 24. While the circuit board 24 and the electronic components 26 arranged on it are completely enclosed by the plastic housing 20, a plastic element or plastic section of the socket 28 is only partially or sectionally enclosed by the plastic housing 20, so that the plastic element of the socket 28 and the pins of the socket 28 enclosed by this plastic element extend out of the plastic housing 20 in a longitudinal extension of the fluid pump 2.

The electronic components 26 arranged on the circuit board 24 are arranged on a side of the circuit board 24 facing away from a fluid chamber 22 of the fluid pump 2, so that a partition wall TW formed in sections with thin walls, which is arranged on a side facing the fluid chamber 22, facing side of the circuit board 24 is formed or molded at least in sections, can be as small as possible in terms of its wall thickness. This improves at least in sections the thermal connection of the circuit board 24 to the fluid chamber 22, through which a fluid that can be conveyed via a hydraulic unit or pump stage 10 circulates. The side of the partition TW facing the fluid chamber 22 can be formed or molded plane-parallel to the side of the circuit board 24 facing the fluid chamber 22.

With a corresponding design of the circuit board 24, the side of the circuit board 24 facing the fluid chamber 22 can be free of the plastic of the plastic housing 20 at least in sections or regions, so that the circuit board 24 can also be thermally connected or coupled directly to the fluid chamber 20 and thus to the conveyable or conveyed fluid in sections or regions. In such a design of the plastic housing 20, the 1 The partition wall TW shown is omitted or at least partially omitted, so that the circuit board 24 could be or be thermally connected or coupled in sections or regions directly or indirectly and/or indirectly or indirectly to the fluid chamber 20 and thus to the conveyable or conveyed fluid.

The plastic housing 20 further encloses or comprises a stator 6 of an electric motor 4 for driving the hydraulic unit or pump stage 10 in the form of, for example, a radial pump stage, which can be designed in the form of a centrifugal pump stage, the pump (impeller) wheel 12 of which is coupled to a rotor 8 of the electric motor 4 via a rotor shaft 16. A bearing 18 is arranged between the rotor 8 and the pump (impeller) wheel 12, via which the rotor shaft 16 is supported against a radial pump stage housing 14.

The electronic assembly is arranged in a region of one end of the plastic housing 20 and is enclosed or surrounded by this plastic housing 20, whereby this end of the plastic housing 20 faces away from the pump stage housing 14. The electronic assembly and the stator 6 are electrically contacted with each other, even if this is not the case in the 1 is not shown, but at the same time are at least partially or completely spaced apart from one another by the plastic housing 20 such that a sufficient fluid space 22 is or can be formed between the rotor 8 or the arrangement comprising the rotor 8 and the rotor shaft 16 and the section of the plastic housing 20 comprising the electronic assembly, through which the pumpable or pumped fluid can circulate to cool the circuit board 24 and the stator 6.

In the embodiment shown, the stator 6 is thermally connected or coupled directly to the fluid chamber 22 and thus to the fluid that can be conveyed or is being conveyed. This means that the stator 6 - unlike the circuit board 24 shown - is free of the plastic of the plastic housing 20 at least in sections or regions on a side facing the fluid chamber 22 and can thus be brought into direct connection with the fluid that can be conveyed or is being circulated.

Alternatively, the stator 6 - analogous to what was previously stated for the circuit board 24 - can also be designed on its side facing the fluid chamber 22 with a thin-walled plastic partition wall - not shown here - at least in sections or regions, which connects or couples the stator 6 indirectly or indirectly to the fluid chamber 22.

Furthermore, it is proposed that the plastic housing 20 be integrally connected to the hydraulic unit 10 at least in sections or regions, or that it be molded onto or removed from the radial pump stage housing 14, which is made up of several parts, at least in sections or regions. This advantageously makes it possible to save on additional or separate components in the form of fastening elements, for example in the form of screws, and sealing elements, for example in the form of sealing rings.

The thermosetting plastic housing 20 can be injection-molded with, for example, a first thermoplastic plastic housing part of the radial pump stage housing 14. And this first thermoplastic plastic housing part of the radial pump stage housing 14 can be integrally connected to a second thermoplastic plastic housing part of the radial pump stage housing 14, for example by means of a welded connection, so that further additional or separate components in the form of fastening elements, for example in the form of screws, and sealing elements, for example in the form of sealing rings, can advantageously be saved.

Alternatively, the plastic housing 20 can also be screwed to the radial pump stage housing 14, for example.

In the embodiment shown, the circuit board 24 is aligned transversely or essentially orthogonally or at right angles to the rotor shaft 16 or to the rotor shaft axis or to the longitudinal extension of the fluid pump 2. However, transversely can also be understood as meaning that the circuit board 24 is aligned against can be arranged inclined above the rotor shaft 16 or the rotor shaft axis or the longitudinal extension of the fluid pump 2.

The proposed design of the plastic housing 20 thus enables a good thermal connection of the circuit board 24 and the stator 6 to the fluid chamber 22 and thus to a coolant circuit (run) in which the fluid pump 2 pumps a water-based coolant, for example. The plastic housing 20 at least largely or completely encloses the circuit board 24 and/or the stator 6. The circuit board 24 and the stator 6 are thus cooled both by the coolant circuit (run) and convectively by the environment.

In order to form the plastic housing 20 - in one embodiment - a plastic, for example in the form of the aforementioned epoxy resin, is encapsulated or injected within a device for receiving the electronic assembly and the stator 6.

In order to form the plastic housing 20 - in a further embodiment - a plastic, for example in the form of the said epoxy resin, is encapsulated or injected within a device for receiving the electronic assembly, the stator 6 and the radial pump stage housing or radial pump stage housing part 14, wherein the plastic is molded onto the radial pump stage housing or radial pump stage housing part 14 at least in some areas.

This proposed design of the plastic housing 20 simplifies the fluid pump 2 in comparison to fluid pumps which, as such, are known to have not only a can or a can, but also sealing elements in the form of sealing rings and fastening elements, for example in the form of screws, in order to connect an actuator in the form of the electric motor 4 and a hydraulic unit in the form of the pump stage 10 to one another to form a fluid pump of the type described here.

This also simplifies the assembly of such a fluid pump 2. And it also simplifies the manufacture of such a fluid pump 2 in comparison to previous or known fluid pumps of this type.

And by eliminating the previously common metal can or metal can, the eddy current losses of the electric motor that occur with such components are also eliminated. This reduces the electric motor's power consumption as well as unwanted heat generation by the electric motor.

By eliminating the can or the split tube, the space required for the electric motor is also reduced. The previously known air gap between the stator and the can or the split tube is also eliminated. This also reduces the space required for the electric motor. This allows the electric motor to be operated even more efficiently.

Although exemplary embodiments are explained in the preceding description, it should be noted that a large number of modifications are possible. It should also be noted that the exemplary embodiments are merely examples that are not intended to limit the scope of protection, applications and structure in any way. Rather, the preceding description provides the person skilled in the art with a guide for implementing at least one exemplary embodiment, whereby various changes, in particular with regard to the function and arrangement of the components described, can be made without departing from the scope of protection as it results from the claims and combinations of features equivalent to these.

Claims (15)

Fluid pump (2), in particular for a motor vehicle, which has a pump stage (10), an electric motor (4) for driving the pump stage (10) and an electronic assembly with a circuit board (24) with electronic components (26) arranged on it, wherein the electronic assembly and a stator (6) of the electric motor (4) are enclosed by a plastic housing (20) of the fluid pump (2) and are arranged and spaced apart from one another by the plastic housing (20) in such a way that the electronic assembly and/or the stator (6) are thermally connected in regions directly and/or indirectly via the plastic housing (20) and without an air gap to a fluid chamber (22) of the plastic housing, via which a fluid that can be conveyed via the pump stage (10) circulates. Fluid pump (2) after claim 1 , wherein a plastic partition wall (TW) is formed between the circuit board (24) and the fluid space (22), which at least partially separates the electronic assembly from the fluid space (22). Fluid pump (2) after claim 1 or 2 , wherein a plastic partition wall is formed between the stator (6) and the fluid space (20), which at least partially separates the stator (6) from the fluid space (22). Fluid pump (2) according to one of the preceding claims, wherein the electronic components (26) are arranged on a side of the circuit board (24) facing away from the fluid chamber (22). Fluid pump (2) according to one of the preceding claims, wherein the plastic housing (20) is also formed at least in sections on a pump stage housing (14). Fluid pump (2) according to one of the preceding claims, wherein the circuit board (24) is aligned substantially at right angles to a rotor shaft (16) of the electric motor (4). Fluid pump (2) according to one of the preceding claims, wherein the plastic housing (20) is injection-molded. Motor vehicle with at least one fluid pump according to one of the preceding Claims 1 until 7 . Method for producing a fluid pump (2) according to one of the preceding Claims 1 until 7 , in which, in order to form a plastic housing (20) of the fluid pump (2), an arrangement of at least one stator (6) of an electric motor (4) for driving a pump stage (10) and an electronic assembly with a printed circuit board (24) with electronic components (26) arranged on it is overmolded with a plastic in such a way, wherein the stator (6) and the electronic assembly are fixed to one another and spaced apart from one another in such a way that the electronic assembly and/or the stator (6) are thermally connected in regions directly and/or indirectly via the plastic housing (20) and without an air gap to a fluid chamber (22) of the plastic housing (20), which is formed during the plastic overmold, via which a fluid that can be conveyed via the pump stage (10) circulates. manufacturing process according to claim 9 , wherein a plastic partition wall (TW) is formed between the circuit board (24) and the fluid space (22), which at least partially separates the electronic assembly from the fluid space (22). manufacturing process according to claim 9 or 10 , wherein a plastic partition wall is formed between the stator (6) and the fluid space (22), which at least partially separates the stator (6) from the fluid space (22). Manufacturing process according to one of the preceding Claims 9 until 11 , wherein the electronic components (26) are arranged on a side of the circuit board (24) facing away from the fluid space (22). Manufacturing process according to one of the preceding Claims 9 until 12 , wherein the plastic housing (20) is additionally molded at least partially onto a pump stage housing (14). Manufacturing process according to one of the preceding Claims 9 until 13 , wherein the circuit board (22) is aligned substantially at right angles to a rotor shaft (16) of the electric motor (4). Use of a fluid pump according to one of the preceding Claims 1 until 7 in a heat transport circuit, in particular of a motor vehicle.

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