HOUSING DEVICE FOR A FLUID PUMP

Abstract

The present invention relates to a housing device (10) for an electric fluid pump, in particular a cooling pump or oil pump, comprising a pump (20) having a pump housing (150), comprising an electric motor (30) having a motor housing (90) and comprising an electronics module (40) having an ECU housing (50, 60) with a housing. The latter consists of a housing body cover and a housing body lower part (60), and a printed circuit board (170) arranged therein. The printed circuit board (170) has an electrical circuit arrangement (220) on one side and is arranged on the housing body lower part (60) using a sealing adhesive (180). At least one opening (190) through which oil can pass is provided in the housing body lower part (60), and the housing body cover (50) and the housing body lower part (60) are sealingly fitted to each other.

Description

[0001] Description

[0002] Housing device for a fluid pump

[0003] The present invention relates to a housing device for an electric fluid pump. It shows design and connection concepts for such an electric fluid pump.

[0004] Electric fluid pumps, especially oil pumps with brushless DC (BLDC) motors and integrated control units, especially for use in the automotive sector for cooling, lubrication, and actuation, must dissipate the heat lost from the control units to keep the control unit temperature below component-specific critical values. Typically, the control unit's circuit board is attached to a heat sink with good heat transfer properties, such as aluminum, which dissipates the heat to the ambient air or to the oil pumped by the pump. Furthermore, the circuit board is sealed and sealed to separate the electronic components from the oil, which could otherwise chemically attack and damage them.

[0005] The problems with state-of-the-art PCB cooling are the relatively high costs of aluminum heat sinks, thermal pastes, and reliable sealing to separate the fluid (including oil) from the electronic components. Solutions using plastic heat sinks typically have limitations regarding heat dissipation values ​​and restrict the use of pumps. A further difficulty is that the heat source is typically not evenly distributed on the PCB. There are several specific hot spots (i.e., transistors, controllers, power traces) on the PCB that must be connected to heat sinks to dissipate the heat over an increased surface area. Furthermore, there is a conflict between creating an electrical connection between the control unit and the motor phases and a cost-effective design with a small number of parts and seals and inexpensive assembly of the pump.In general, it is also preferable to reduce the size of the pump and its weight for cost and space reasons.

[0006] It is therefore an object of the present invention to eliminate the above-mentioned disadvantages and to provide a compromise between the amount of parts required, parts costs and the cooling capabilities of the pump control units.

[0007] According to the invention, this object is achieved by a housing device for an electric fluid pump according to claim 1, in which the housing device has a printed circuit board, which printed circuit board has SMT components on one side, wherein the printed circuit board is arranged on the housing body lower part using a sealing adhesive, wherein at least one opening is provided in the housing body lower part through which fluid or oil can pass, and wherein the housing body cover and the housing body lower part are installed with one another in a fluid-tight manner. The printed circuit board is fastened to the housing body lower part and at the same time is sealed off from the wet space to prevent oil from entering. Fluid or oil can reach the underside of the printed circuit board through the at least one opening. This enables direct cooling of the printed circuit board by the fluid.The prerequisite for cooling is the presence of fluid in the motor compartment, which is achieved by appropriately managing the pump's leakage flow. The housing cover and housing base are thus tightly sealed against environmental influences. The goal is to use the same sealing compound to seal the individual housing components, as well as the circuit board seal against the oil and wet areas, and to apply them in a single process step.

[0008] In one embodiment, the circuit board has contact elements on the side facing away from the housing cover for contact with contact elements emanating from the electric motor, which extend through the at least one opening therein. Since the electrical contact elements are designed as SMT contacts, they do not require a through-hole on the circuit board. Since the circuit board is made of epoxy material and no through-holes are required, the circuit board can function as a separating and sealing layer against fluid / oil or the wet space.

[0009] It is advantageous if the circuit board can be connected via an electrical connecting element.

[0010] In a further embodiment, the housing body cover is a

[0011] The ECU housing upper part and the housing body lower part form an ECU housing lower part. An advantageous embodiment provides that the ECU housing lower part is arranged on the motor housing of the electric motor and forms the housing upper part of the motor housing.

[0012] One possible arrangement is to mount the pump housing on the side of the engine housing facing away from the ECU housing base.

[0013] It is advantageous if the ECU housing base, the motor housing and the pump housing are screwed together.

[0014] According to the invention, seals are provided between the adjacent housing parts. This eliminates the need for a geometrically complex seal or one consisting of multiple parts.

[0015] In one embodiment, the housing body cover is an ECU housing upper part and the housing body lower part is a housing upper part of the motor housing of the electric motor.

[0016] Preferably, a pump is arranged in the pump housing on the side of the engine housing facing away from the ECU housing top.

[0017] In one embodiment, the ECU housing body upper part, the motor housing and the pump housing are sealingly connected to one another.

[0018] According to the invention, the housing body cover can be an ECU housing upper part and the housing body lower part can be an upper housing part of a pump housing.

[0019] In a further embodiment, an electric motor is arranged on the side of the pump housing facing away from the ECU housing upper part.

[0020] Preferably, the ECU housing upper section, the pump housing, and the motor housing are sealed together. They are thus sealed against environmental influences.

[0021] Preferably, the ECU housing base, the motor housing and the pump housing are screwed together.

[0022] Particularly preferably, the housing device is made of plastic. The invention will now be described in more detail with reference to the accompanying figures. In the figures:

[0023] Figure 1 is a sectional view of a first embodiment of the housing device according to the invention;

[0024] Figure 2 is a sectional view of a second embodiment of the housing device according to the invention; and

[0025] Figure 3 is a sectional view of a third embodiment of the housing device according to the invention.

[0026] Corresponding parts are provided with the same reference numerals in all figures.

[0027] Figure 1 shows an embodiment of a housing device 10 according to the invention, such as is used for an electric oil pump. The housing device 10 comprises a pump 20, a motor 30, and an electronic control unit (ECU) 40.

[0028] In this embodiment, the housing device 10 further comprises a housing body cover 50, which simultaneously represents the ECU housing upper part 50, and a housing body lower part 60, which simultaneously represents the ECU housing lower part 60. The ECU housing upper part 50 and the ECU housing lower part 60 are assembled together by means of a seal 70 and are screwed as the housing upper part 80 onto a motor housing 90 of the electric motor 30 by means of a sealing element 100.

[0029] The electric motor 30 comprises a shaft 110, a rotor 120, and a stator 130, here a brushless DC motor with the motor housing 90, and is constructed in a known manner. On the side facing away from the ECU housing 50, 60, the pump 20 is arranged on the motor housing 90 of the electric motor 30 with a pump housing 150. The shaft 110 of the motor 30 and the pump 20 are integral and extends from the pump housing 150 into the motor housing 90. The pump housing 150, the motor housing 90, and the ECU housing lower part 60 are connected to one another by means of a screw connection 160, with sealing means 100, 160 being provided between the pump housing 150 and the motor housing 90, and between the motor housing 90 and the ECU housing lower part 60.

[0030] In Figure 1, a printed circuit board 170 is further arranged inside the ECU housing 50, 60 and is bonded to the ECU housing lower part 60 using a sealing adhesive 180, e.g., epoxy adhesive. The ECU housing lower part 60 has openings 190 through which cooling media (typically the fluid pumped by the pump 20) can pass and cool heat sources through direct contact of the fluid, e.g., oil, with the printed circuit board 170 in the region of the openings 190. The design of the pump 20 ensures a certain amount of oil exchange of the oil that comes into contact with the hot spots (i.e., transistors, controllers, power conductors) of the printed circuit board 170, in order to also transfer heat through oil movement. The leakage oil internal to the pump is preferably used to ensure oil exchange in the required cooling volumes.

[0031] The circuit board 170 is electrically connectable by means of a connecting pin 200, which extends through the ECU housing lower part 60 in the direction out of the housing lower part 60 into a connection area 210.

[0032] Circuit assemblies 220, SMT components such as MOSFETs, are arranged on the side of the circuit board 170 facing away from the motor housing 90. Although not shown here, it is also possible to mount the components on the side of the circuit board 170 that is bonded to the ECU housing base 60 by creating pockets in the housing to accommodate the electronic components. These circuit assemblies 220, which are designed as SMT components, do not require through-holes on the circuit board 170. Since the circuit board 170 is made of epoxy material and no through-holes are required, it can function as a separating or sealing plane with respect to the oil or wet chamber.

[0033] On the side of the circuit board 170 facing the motor housing 90, SMT male pins 230 are mounted, which are in contact with SMT female pins 240 extending from the stator 130 of the motor 30 for electrical contact with the motor 30. The SMT male pins 230 can also extend from the stator 130 for electrical contact with SMT female pins 240 arranged on the circuit board 170. In both cases, the motor phases are connected through the openings 190 formed in the ECU housing base 60. The motor phase contacts are typically contacts that can be connected to the circuit board 170 without any special assembly force support, or even without any.

[0034] Figure 2 shows a second embodiment of the housing device 10 according to the invention, wherein only the extent to which the housing devices 10 differ is discussed.

[0035] In this embodiment, the housing device 10 comprises a housing body cover 250, which represents an ECU housing 250 that is completely open on the side facing the motor housing 90. The ECU housing 250 is arranged on the adjacent motor housing 90, namely, screwed, wherein the ECU housing 250 and the motor housing 90 are tightly installed by means of a seal 260.

[0036] The electric motor 30 accommodated in the motor housing 90 corresponds to that shown in Figure 1, to the description of which reference is made. The pump 20 with the pump housing 150 is connected to the motor housing 90 in the same way as in the embodiment shown in Figure 1.

[0037] The embodiment according to Figure 2 differs from that in Figure 1 in that the circuit board 170 is also arranged inside the ECU housing 250, but is glued to the upper housing section 270 of the motor housing 90 using sealing adhesive 180. Openings 280 are provided in the upper housing section 270 of the motor housing 90, through which the cooling medium can reach the rear side of the circuit board 170, and the necessary cooling of the circuit board is achieved through the oil exchange.

[0038] From the circuit board 170, the connecting pin 200 extends through the ECU housing 250 to the terminal area 210 for the electrical connection.

[0039] Just as in the embodiment in Figure 1, circuit arrangements 220 are provided on the side of the circuit board 170 facing away from the motor housing 90. Reference is made to the description therein.

[0040] The motor phase contacts 230, 240 are also designed corresponding to those in Figure 1. Figure 3 shows a housing device 10 in which the arrangement of pump 20 with pump housing 150, electric motor 30 with motor housing 90, and electric control unit 40 with ECU housing 250 differs from the arrangement of the same in Figures 1 and 2.

[0041] The housing device 10 of this embodiment comprises the housing body cover 250, which also forms the ECU housing 250 here. The ECU housing 250 is completely open on the side facing the pump housing 150. Adjacent to the ECU housing 250 is the pump housing 150 with the pump 20, to which the ECU housing 250 is attached by means of a screw connection. On the side facing away from the ECU housing 250 is the motor housing 90 with the electric motor 30. The ECU housing, the pump housing 150, and the motor housing 90 are assembled together via screws 290. Seals 260, 300 are arranged between the ECU housing 250 and the pump housing 150 and between the pump housing 150 and the motor housing 90 in order to seal the interior of the housing device in a fluid-tight manner and to seal it off from the outside to the wet space.

[0042] The circuit board 170 is bonded to the upper housing area 310 of the pump housing 150 with a sealing adhesive 160. Openings 320 are formed in the upper housing area 310 of the pump housing 150, through which cooling medium can flow from the interior of the pump housing 150 to the rear of the circuit board 170, and this oil exchange cools the circuit board 170. The heat from the circuit board 170 is thus dissipated close to the point where it is generated. This allows for very small cooling surfaces with good heat dissipation. Due to this direct cooling of the circuit board 170, the housing material is no longer the primary determining factor for circuit board cooling. Thus, more cost-effective materials, such as plastic, can be used for the housing material, and the size of the pump can be reduced.

[0043] In this embodiment, circuit arrangements 220, SMT components, e.g., MOSFETs, are also arranged on the side of the circuit board 170 facing away from the pump housing 150, namely on the side not bonded to the pump housing 150. Here, too, it is possible, as in the embodiment of Figure 1, to provide the components on the side of the circuit board 170 bonded to the pump housing 150. On the side of the circuit board 170 facing the pump housing 150, SMT female pins 240 are mounted, which are in contact with SMT male pins 230 for electrical contact with the motor 30. The SMT male pins 230 extend from the stator 130 of the motor 30 through the pump 20 through the openings in the upper housing region 310 of the pump housing 150 and contact the SMT female pins 240 provided on the circuit board 170 in the region of the openings 320.This design also reduces the number of parts and sealing requirements for the housing assembly due to the low mating forces of the motor phase contacts. It also offers good assembly.

[0044] Housing devices of the type described above can be used, for example, in automotive hydraulic systems, electric drives for electric and hybrid vehicles, automatic transmissions, commercial vehicles, oil production systems, in nautical applications, battery cooling systems and lubrication systems.

[0045] List of reference symbols

[0046] 10 Housing device

[0047] 20 pump

[0048] 30 engine

[0049] 40 Electrical control unit, ECU

[0050] 50 ECU housing upper part

[0051] 60 ECU housing base

[0052] 70 Seal

[0053] 80 Housing cover

[0054] 90 engine housing

[0055] 100 sealing element

[0056] 110 Wave

[0057] 120 rotor

[0058] 130 Stator

[0059] 140 pump

[0060] 150 pump housings

[0061] 160 sealants

[0062] 170 circuit board

[0063] 180 sealing adhesive

[0064] 190 openings

[0065] 200 connecting pins

[0066] 210 connection area

[0067] 220 circuit arrangement

[0068] 230 SMT male pins

[0069] 240 STM female pins

[0070] 250 housing body cover

[0071] 260 Seal

[0072] 270 Upper housing area of ​​the motor housing 90

[0073] 280 openings in the engine housing 90

[0074] 290 screw connection

[0075] 300 sealing element

[0076] 310 Upper housing area of ​​the pump housing 150

[0077] 320 openings

Claims

Patent claims 1. Housing device (10) for a fluid pump, in particular a cooling pump or oil pump, comprising a pump (20) with a pump housing (150), an electric motor (30) with a motor housing (90), and an electronic module (40) with an ECU housing (50, 60), with a housing consisting of a housing body cover (50) and a housing body lower part (60, 90, 150), a printed circuit board (170) arranged therein, which printed circuit board (170) has an electrical circuit arrangement (220) on one side, wherein the printed circuit board (170) is arranged on the housing body lower part (60) with a sealant (180), wherein at least one opening (190) is provided in the housing body lower part (60) through which oil can pass and reach the printed circuit board (170), and wherein the housing body cover (50) and the housing body lower part (60, 90, 150) are sealed are built together.

2. Housing device (10) according to claim 1, wherein the circuit board (170) has contact elements (230, 240) on the side facing away from the housing body cover (50) for contact with contact elements (240, 230) extending from the electric motor (30) through the at least one opening (190) therein.

3. Housing device (10) according to one of claims 1 or 2, wherein the circuit board (170) can be connected via an electrical connecting element (200).

4. Housing device according to one of claims 1 to 3, wherein the housing body cover (50) is an ECU housing upper part (50) and the housing body lower part is an ECU housing lower part (60).

5. Housing device (10) according to claim 4, wherein the lower part of the ECU housing (60) is arranged on the motor housing (90) of the electric motor (30) and forms the upper part of the motor housing (90).

6. Housing device (10) according to claim 5, wherein the pump housing (150) is arranged on the side of the motor housing (90) facing away from the lower part of the ECU housing (60).

7. Housing device (10) according to claim 6, wherein the ECU housing lower part (60), the motor housing (90) and the pump housing (150) are screwed together.

8. Housing device (10) according to claim 7, wherein seals (70, 100, 160) are provided between the respective housing parts (60, 90, 150) arranged one another.

9. Housing device (10) according to one of claims 1 to 3, wherein the housing body cover is an ECU housing upper part (250) and the housing body lower part is a housing upper part of the motor housing (90) of the electric motor (30).

10. Housing device (10) according to claim 9, wherein the pump (20) is arranged in the pump housing (150) on the side of the motor housing (90) facing away from the ECU housing top (250).

11. Housing device (10) according to claim 10, wherein the ECU housing top (250), the motor housing (90) and the pump housing (150) are sealedly connected to each other.

12. Housing device (10) according to one of claims 1 to 3, wherein the housing body cover is an ECU housing top part (250) and the housing body bottom part (310) is a housing top part of a pump housing (150).

13. Housing device (10) according to claim 12, wherein an electric motor (30) is arranged on the side of the pump housing (150) facing away from the ECU housing top (250).

14. Housing device (10) according to claim 13, wherein the ECU housing body upper part (250), the pump housing (150) and the motor housing (90) are sealedly connected to each other.

15. Housing device (10) according to one of claims 1 to 14, wherein the housing body is made of plastic.