EP3472470B1 - Electric fluid pump for a motor vehicle - Google Patents

Description

The invention relates to an electric fluid pump for a motor vehicle with a housing assembly that defines at least one pump chamber and one motor chamber, the pump chamber having a pump rotor chamber for a pump unit with a pump rotor, and a drive motor with a motor stator with a motor coil arrangement and a motor rotor located in the engine chamber is provided, wherein the pump chamber and the motor chamber have a common front wall, wherein the motor rotor is connected in a torque-proof manner to a rotor shaft which is guided through the common front wall and on which the pump rotor is arranged in a torque-proof manner, and a motor controller is provided for controlling the drive motor, wherein the common end wall is designed as a mounting wall part on which at least the engine control is arranged in a heat-conducting manner.

A fluid pump for a motor vehicle is used to pump a fluid in a fluid circuit. It is known, for example, to pump a liquid heat carrier, always referred to below as a coolant, into a heating or coolant circuit. The coolant circuit does not necessarily have to be a main stream of the circuit, but can also form a side stream. Essentially, however, engine units are to be cooled in the operating state by such a coolant circuit. Electrically driven coolant pumps have been developed in particular in order to adapt the pump performance of such a coolant pump to the respective operating state of the motor vehicle engine. An electronically commutated drive motor drives a pump unit. The problem with such electronically commutated drive motors is basically the cooling of the drive motor and the motor controller for driving the motor coil arrangement has a plurality of line semiconductors which can heat up considerably during operation and must be cooled accordingly in order to prevent their destruction. In this case, the motor coil arrangement is a heat source that should be thermally shielded or cooled as well as possible in relation to the motor control. It is therefore known from the prior art to use the coolant to be pumped in order to flow through the engine compartment in order in this way to cool an engine control space in which the engine control is provided. An example of an electric coolant pump constructed in this way can be found in EP 2 796 722 A1 .

A major disadvantage of this known pump concept is the relatively large amount of space that this pump requires and the complicated fluid routing for cooling. With regard to simplified cooling is from the prior art according to DE 199 43 862 A1 a generic electric fluid pump is known. In addition, it is also from the DE 199 43 577 A1 known to arrange an electronic module in thermally conductive contact with the rotor space in a receiving space. From the DE 101 03 209 A1 it is also known to provide a one-piece motor housing together with a receiving space for electronic components.

Against the background of an ever smaller amount of installation space available, it is no longer possible or difficult to accommodate and assemble such a pump at desired assembly locations. It should be clear that these disadvantages can also occur with electrically operated oil pumps and, for example, with compressors and fans.

It is therefore the object of the present invention to avoid the disadvantages mentioned above in a simple and inexpensive manner.

This object is achieved in that the drive motor is an asymmetrically permanently excited drive motor, the motor stator and/or the motor coil arrangement being arranged on the mounting wall part and the motor coil arrangement arranged on the motor stator being provided on a side facing away from the motor controller in relation to the rotor shaft is. With such a design, a closed engine control room is no longer required and additional space is made possible for the engine control in the engine compartment, as a result of which a considerable reduction in length and thus a saving in installation space is achieved. In addition, a saving in components can be realized. In addition, the liquid flow for cooling the drive motor and the motor control is significantly simplified. A particularly space-saving drive motor is provided in that it is designed as a 1-phase, asymmetrical drive motor.

In a particularly advantageous embodiment, the motor controller is arranged on the mounting wall part via a large-area plate element, in particular a circuit board, made of a heat-conducting material. In this way, an optimal heat transfer from the motor controller to the mounting wall part cooled by the cooling fluid can be ensured.

In a particularly advantageous manner, a cover element is fastened to the mounting wall part as part of the motor housing, and a closed motor housing is thus formed. However, it is also possible to arrange the engine compartment openly in the motor vehicle. If a cover element is present, the motor stator and/or the motor coil arrangement can be arranged on the cover element, which can offer advantages during assembly.

It is also advantageous for heat dissipation if the motor stator and/or the motor coil arrangement is arranged on the assembly part via a heat-conducting means, such as a gap pad or a casting agent. Furthermore, the rotor shaft can be mounted in the mounting wall part via bearing means.

The mounting wall part advantageously has at least one shoulder element which runs axially parallel to the rotor shaft and on which the motor stator is fastened by means of fastening means. This ensures a particularly compact arrangement, with the rotor shaft and thus the motor rotor being coaxial with the motor stator in a simple manner.

Advantageously, a bearing element is provided for a containment shell, on which the containment shell is supported in a sealing manner, so that a motor rotor space is created as a space that carries coolant. A pot end element can be provided in a sealing manner on the can and/or the motor stator. Here, however, the pot end element can also be an integral part of the split pot. Further bearing means for the rotor shaft can then be provided in the pot-end element.

In a particularly advantageous way, a non-contact sensor, in particular a Hall sensor, is provided in the area of the motor rotor, in particular in the area of the outside of the containment shell or integrated into it.

• Figur 1 eine geschnittene Seitenansicht einer erfindungsgemäßen Fluidpumpe,
• Figur 2 eine geschnittene Endansicht der elektrischen Fluidpumpe aus Figur 1, und
• Figur 3 eine perspektivische Ansicht eines Motorraumes eines Montagewandteils der erfindungsgemäßen Fluidpumpe.

The invention is explained in more detail below with reference to a drawing, which shows:

• figure 1 a sectional side view of a fluid pump according to the invention,
• figure 2 Figure 12 shows a sectional end view of the electric fluid pump figure 1 , and
• figure 3 a perspective view of a motor compartment of a mounting wall part of the fluid pump according to the invention.

figure 1 shows a sectional side view of an electric fluid pump 2 according to the invention, which is designed as a coolant pump, for a motor vehicle not shown in detail. It should be clear that the invention is not limited to such a coolant pump. Rather, all electric pumps and blowers fall within the scope of the invention. The electric coolant pump 2 has a housing assembly 4 which defines a pump chamber 6 for a pump assembly 7 and a motor chamber 8 . The pump chamber 6 has a pump rotor chamber 10 in a known manner, in which a pump rotor 12 is provided and is formed by a pump housing 13 in the present exemplary embodiment. Furthermore, the pump housing 13 has, in a known manner, an inlet 14 and an in figure 2 outlet 16 shown. The pump chamber 6 and the motor chamber 8 are delimited by a common end wall 18 . In the present exemplary embodiment, a cover element 20 is also provided, which is fastened to the common end wall 18 and thus forms a motor housing 22 with a closed motor compartment 8 in which a drive motor 24 and a motor controller 26 are provided. However, it is also conceivable to omit the cover element and thus form an open engine compartment 8 .

The drive motor 24 is designed as an asymmetrically permanently excited drive motor, with a motor coil arrangement 30 arranged on a motor stator 28 being based on one Rotor shaft 32 is provided on the side facing away from the motor controller 26 . In a known manner, a motor rotor 34 is arranged on the rotor shaft 32 in a rotationally fixed manner. The pump rotor 12 is likewise fastened in a rotationally fixed manner on the rotor shaft 32 . The motor stator 28 is designed here in a known manner as a laminated core.

According to the invention, it is now provided that the common end wall is designed as a mounting wall part, on which the motor controller 26 and the motor stator 28 are arranged in the present exemplary embodiment. The motor coil arrangement 30 bears against the mounting wall part 18 via a casting agent 36 and can thus be cooled in a simple manner. The motor controller 26 , on the other hand, is provided on a large-area circuit board 38 , which in turn is fastened to the mounting wall part 18 . Due to the large-area thin circuit board 38 there is an optimal heat transfer from the engine control 26 to the mounting wall part 18 cooled by the cooling fluid.

The mounting wall part 18 also has a bearing element 40 on the inside of which a containment shell 42 with an integrated pot end element 44 is supported in a sealed manner via sealing means 46 . A motor rotor space 48 that is delimited in this way can therefore be flowed through by cooling fluid.

The motor stator 28 designed as a stator assembly is arranged on shoulder elements 58 running parallel to the axis via screws 60 on the mounting wall part 18 (see figure 3 ).

The rotor shaft 32 extending through the mounting wall part 18 is mounted in the pot end element 42 and in the mounting wall part 18 via suitable bearing means 50 , 52 . In figure 2 only schematically and in figure 3 shown in more detail is a non-contact sensor 54 designed as a Hall sensor, which in a known manner indicates a rotational position of the drive motor 24 is monitored and integrated into the can 42 in the area of a pole gap of the motor stator 28 .

figure 2 now shows the electric fluid pump 2 in a sectional end view figure 1 . Motor stator 28, which is designed as a stator core and has openings 56 through which the in figure 3 Screws 60 shown can be guided to attach the stator core 28 to the cylindrical shoulder elements 58 of the mounting wall part 18. As can be clearly seen here, the motor stator 28 has a rectangular stator geometry, which makes it possible to reduce sheet metal production costs. Furthermore, the arrangement according to the invention enables the electronics to be simplified and a simpler processor to be used by using the Hall sensor 54 .

Claims (11)

1. Electric fluid pump for a motor vehicle, comprising a housing composite (4), which defines at least a pump space (6) and a motor space (8), wherein the pump space (6) has a pump rotor space (10) for a pump unit (7) having a pump rotor (12) and wherein a drive motor (24) having a motor stator (28) having a motor coil assembly and a motor rotor is provided in the motor space (8), wherein the pump space (6) and the motor space (8) have a common end wall (18), wherein the motor rotor (34) is connected to a rotor shaft (32) for conjoint rotation, which rotor shaft is fed through the common end wall (18) and on which rotor shaft the pump rotor (12) is arranged for conjoint rotation, and wherein a motor controller (26) is provided for controlling the drive motor (24), wherein the common end wall (18) is designed as a mounting wall part, on which at least the motor controller (26) is arranged in a thermally conductive manner, characterized in that the drive motor (24) is an asymmetric permanently excited drive motor, wherein the motor stator (28) and/or the motor coil assembly (30) are provided at the mounting wall part (18), and wherein the motor coil assembly (30) arranged on the motor stator (28) is provided on a side which, in relation to the rotor shaft (32), is opposite the motor controller (26).
2. Electric fluid pump of claim 1, characterized in that the motor control (26) is arranged on the mounting wall part (18) via a large-surface plate element (38), in particular a circuit board, of a thermally conductive material.
3. Electric fluid pump of one of the preceding claims, characterized in that a cover element (20) is fastened on the mounting wall part (1) as a part of the motor housing (8).
4. Electric fluid pump of claim 3, characterized in that the motor stator (28) and/or the motor coil arrangement (30) are arranged on the cover element (20).
5. Electric fluid pump of one of the preceding claims, characterized in that the motor stator (28) and/or the motor coil arrangement (30) are arranged on the mounting wall part (18) by a thermally conductive (36), such as e.g. a gap pad or a potting material.
6. Electric fluid pump of one of the preceding claims, characterized in that the rotor shaft (32) is supported in the mounting wall part (18) via bearing means (50).
7. Electric fluid pump of one of the preceding claims, characterized in that the mounting wall part (18) comprises at least one shoulder element (58) extending axially parallel to the rotor shaft (32), on which element the motor stator (28) is fastened via fastening means.
8. Electric fluid pump of one of the preceding claims, characterized in that a bearing member (40) for a can (42) is provided on which the can (42) is supported in a sealing manner.
9. Electric fluid pump of claim 8, characterized in that a pot end element (44) is provided in a sealing manner on the can (42) and/or the motor stator (26).
10. Electric fluid pump of claim 9, characterized in that further bearing means (50) for the rotor shaft (32) are provided in the pot end element (44).
11. Electric fluid pump of one of the preceding claims, characterized in that a contactless sensor (54), in particular a Hall sensor, is provided in the region of the motor rotor, in particular in the region of the outer side of the can (42) or is integrated in the same.

Images