U.S. patent application number 13/979377 was filed with the patent office on 2014-01-09 for electrical motor vehicle coolant pump.
This patent application is currently assigned to PIERBURG PUMP TECHNOLOGY GMBH. The applicant listed for this patent is Thomas Joachim Gibat, Witold Joschko. Invention is credited to Thomas Joachim Gibat, Witold Joschko.
Application Number | 20140010684 13/979377 |
Document ID | / |
Family ID | 44140682 |
Filed Date | 2014-01-09 |
United States Patent
Application |
20140010684 |
Kind Code |
A1 |
Joschko; Witold ; et
al. |
January 9, 2014 |
ELECTRICAL MOTOR VEHICLE COOLANT PUMP
Abstract
An electric coolant pump for a motor vehicle includes a wet
section in which is arranged an impeller and a permanently
magnetized motor rotor of an electronically commutated
electromotor, a dry section in which is arranged an electric
circuit board comprising a plurality of power semiconductors which
each comprise a cooling lug, and a partition wall lying in a
traverse plane. The partition wall is arranged to separate the wet
section and the dry section. The plurality of power semiconductors
are each arranged on a proximal side of the electric circuit board
facing the partition wall. Each cooling lug is arranged on a
cooling lug conductor strip. On a side of the partition wall facing
the electric circuit board, the partition wall comprises a heat
conductor which is configured to be electrically non-conductive.
The heat conductor is arranged to rest directly on a respective
cooling lug conductor strip.
Inventors: |
Joschko; Witold; (Kempen,
DE) ; Gibat; Thomas Joachim; (Krefeld, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Joschko; Witold
Gibat; Thomas Joachim |
Kempen
Krefeld |
|
DE
DE |
|
|
Assignee: |
PIERBURG PUMP TECHNOLOGY
GMBH
Neuss
DE
|
Family ID: |
44140682 |
Appl. No.: |
13/979377 |
Filed: |
July 27, 2011 |
PCT Filed: |
July 27, 2011 |
PCT NO: |
PCT/EP11/62864 |
371 Date: |
September 27, 2013 |
Current U.S.
Class: |
417/410.1 |
Current CPC
Class: |
H05K 7/209 20130101;
F04D 13/0686 20130101; F04B 17/03 20130101; F04D 29/5813
20130101 |
Class at
Publication: |
417/410.1 |
International
Class: |
F04B 17/03 20060101
F04B017/03 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 13, 2011 |
EP |
11150865.1 |
Claims
1-5. (canceled)
6. An electric coolant pump for a motor vehicle, the electric
coolant pump comprising: a wet section in which is arranged an
impeller and a permanently magnetized motor rotor of an
electronically commutated electromotor; a dry section in which is
arranged an electric circuit board comprising a plurality of power
semiconductors which each comprise a cooling lug; and a partition
wall lying in a traverse plane, the partition wall being arranged
to separate the wet section and the dry section, wherein, the
plurality of power semiconductors are each arranged on a proximal
side of the electric circuit board facing the partition wall, each
cooling lug is arranged on a cooling lug conductor strip, and on a
side of the partition wall facing the electric circuit board, the
partition wall comprises a heat conductor which is configured to be
electrically non-conductive, the heat conductor being arranged to
rest directly on a respective cooling lug conductor strip.
7. The electric coolant pump as recited in claim 6, wherein, on the
side of the partition wall facing the circuit board, the partition
wall further comprises a recess for each of the plurality of power
semiconductors, into which recess a respective power semiconductor
is arranged to extend axially.
8. The electric coolant pump as recited in claim 6, wherein the
cooling lug conductor strip comprises a cooling lug conductor strip
surface area and the cooling lug comprises a cooling lug surface
area, wherein the cooling lug conductor strip surface area is at
least twice the size of the cooling lug surface area.
9. The electric coolant pump as recited in claim 8, wherein the
cooling lug conductor strip surface area is at least three times
the size of the cooling lug surface area.
10. The electric coolant pump as recited in claim 8, wherein the
cooling lug conductor strip surface area is at least five times the
size of the cooling lug surface area.
11. The electric coolant pump as recited in claim 6, wherein the
electronically commutated electromotor comprises a separating can
which is configured to separate the wet section from the dry
section.
12. The electric coolant pump as recited in claim 6, wherein the
electric circuit board further comprises electric controls
configured to drive the plurality of power semiconductors, the
electric controls being arranged on a side of the circuit board
averted from the partition wall.
Description
CROSS REFERENCE TO PRIOR APPLICATIONS
[0001] This application is a U.S. National Phase application under
35 U.S.C. .sctn.371 of International Application No.
PCT/EP2011/062864, filed on Jul. 27, 2011 and which claims benefit
to European Patent Application No. 11150865.1, filed on Jan. 13,
2011. The International Application was published in German on Jul.
19, 2012 as WO 2012/095192 A1 under PCT Article 21(2).
FIELD
[0002] The present invention relates to an electric motor vehicle
coolant pump for supplying coolant to an internal combustion
engine, wherein the brushless electromotor is commutated
electronically.
BACKGROUND
[0003] An electric motor vehicle coolant pump having a brushless,
electronically commutated electromotor as the drive motor,
comprises control electronics and power semiconductors that can
generate heat during operation. A coolant pump runs practically all
the time, albeit at different speeds, during the operation of a
motor vehicle internal combustion engine to be supplied with
coolant. Under adverse conditions, for example, when the internal
combustion engine is under full load, at low motor vehicle speed,
and at high outside temperatures, the coolant pump must run under
full load for extended periods. The significant thermal losses of
the power semiconductors have to here be dissipated in a reliable
manner to avoid the destruction of the power semiconductors.
[0004] DE 10 2007 054 060 describes an electric motor vehicle
coolant pump with a brushless separating can electromotor, wherein
the cooling lugs of the power semiconductors are in direct contact
with the partition wall that separates the wet area from the dry
area of the coolant pump. This may enable good heat dissipation
from the power semiconductor; however, the cooling lug is not
electrically connected directly with a conductor on the circuit
board.
SUMMARY
[0005] An aspect of the present invention is to provide an electric
motor vehicle coolant pump having an electronically commutated
electromotor, wherein the power semiconductors are well cooled, and
the cooling lugs of the power semiconductors are contacted directly
with a conductor strip on the circuit board.
[0006] In an embodiment, the present invention provides an electric
coolant pump for a motor vehicle which includes a wet section in
which is arranged an impeller and a permanently magnetized motor
rotor of an electronically commutated electromotor, a dry section
in which is arranged an electric circuit board comprising a
plurality of power semiconductors which each comprise a cooling
lug, and a partition wall lying in a traverse plane. The partition
wall is arranged to separate the wet section and the dry section.
The plurality of power semiconductors are each arranged on a
proximal side of the electric circuit board facing the partition
wall. Each cooling lug is arranged on a cooling lug conductor
strip. On a side of the partition wall facing the electric circuit
board, the partition wall comprises a heat conductor which is
configured to be electrically non-conductive. The heat conductor is
arranged to rest directly on a respective cooling lug conductor
strip.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention is described in greater detail below
on the basis of embodiments and of the drawings in which:
[0008] FIG. 1 shows a schematic longitudinal section of a motor
vehicle coolant pump having a partition wall and a circuit board
with power semiconductors;
[0009] FIG. 2 shows an enlarged illustration of the partition wall
and the circuit board of FIG. 1; and
[0010] FIG. 3 shows a top plan view on the proximal side of the
circuit board of the FIGS. 1 and 2.
DETAILED DESCRIPTION
[0011] The coolant pump includes a wet section in which an impeller
and a permanently magnetically, i.e., continuously, excited motor
rotor of the electronically commutated electric motor are arranged.
The coolant pump further has a dry section in which, among others,
an electric circuit board is arranged which supports a plurality of
power semiconductors with a respective cooling lug for each. The
power semiconductors serve to directly drive the stator-side motor
coils.
[0012] The wet section and the dry section are separated by an
electrically conductive partition wall lying in a transverse plane.
The partition wall can, for example, be made of an electrically
conductive material, but can also be made of electrically
non-conductive material, for example, a plastics material. A
circuit board is arranged so as to lie in a transversal plane
adjacent to the partition wall, wherein the power semiconductors
are situated on the proximal side of the circuit board. The
electric terminals of the power semiconductors, including the
cooling lugs, which each also represent an electric terminal, are
soldered to corresponding conductor strips on the circuit
board.
[0013] Each of the cooling lugs of the power semiconductors is
arranged on a respective individual conductor strip and is soldered
thereto, i.e., the cooling lugs are electrically separated from
each other. The conductor strips connected with the cooling lugs
rest on the partition wall with their portions protruding beyond
the surface of the respective cooling lug, wherein an electrically
non-conductive heat conducting means is provided between the
partition wall and the conductor strips, which electrically
insulates the conductor strips from the partition wall, but
conducts heat well. A heat conducting film, a heat conducting paste
or a heat conducting adhesive are particularly suited as heat
conducting means.
[0014] The conductor strip onto which the cooling lug is soldered
must thus have a larger surface area than the cooling lug itself
and/or than the area of the cooling lug connected with the
conductor strip. Only the portion of the respective conductor strip
extending beyond the cooling lug rests on the electrically
non-conductive heat conducting means which in turn rests
immediately on the partition wall. The wet section is provided on
the side of the partition wall opposite the circuit board, which is
the reason why the coolant circulating there can dissipate large
heat quantities from the partition wall.
[0015] The heat flow of waste heat from the power semiconductor
thus flows from its cooling lug via the conductor strip, onto which
the cooling lug is soldered, and the electrically non-conductive
heat conducting means to the partition wall, from where the heat is
dissipated by the coolant. In this manner, an effective cooling of
the power semiconductors is possible, while the cooling lugs of the
power semiconductors are each still electrically connected or
soldered to an individual conductor strip of the circuit board.
[0016] On the side facing the circuit board, the partition wall
can, for example, comprise a respective semiconductor recess for
each semiconductor into which the semiconductor extends axially.
The semiconductor recesses are necessary so that the base area of
the partition wall can rest directly on the conductor strip with
interposition of the heat conducting means. On the side of the
circuit board facing the partition wall, only the power
semiconductors are arranged and no other electronic components are
provided. The entire control electronics for driving the power
semiconductors can, for example, be arranged on the distal side of
the circuit board, for example, the side averted from the partition
wall. Corresponding through-holes are provided to make an electric
connection between the proximal and the distal side, which
through-holes, however, exclusively establish the electric contact
and are not suited for heat transport.
[0017] In an embodiment of the present invention, the electromotor
can, for example, comprise a separating can separating the wet
section from a dry section in which, among others, the stator-side
motor coils are arranged. The dry section, in which the motor coils
are situated, may be separated from the dry section, in which the
circuit board is located. The partition wall, lying in a transverse
plane, is part of the separating can so that the partition wall is
flown to and cooled directly by the coolant.
[0018] In an embodiment of the present invention, the surface area
of the conductor strip can, for example, be at least twice, for
example, at least three times, for example, at least five times,
the size of the surface area of the respective cooling lug by which
the same is fixed or soldered to the conductor strip. The larger
the surface area of the power semiconductors is, the larger is the
surface area for the dissipation of heat from the conductor strip
and/or the larger the contact surface between the conductor strip
and the heat conducting means or the partition wall can be.
[0019] The following is a detailed description of an embodiment of
the present invention with reference to the drawing.
[0020] FIG. 1 is a schematic longitudinal section of an electrical
motor vehicle coolant pump 10 that pumps a liquid coolant in a
coolant circuit serving to cool an internal combustion engine (not
illustrated). The coolant pump 10 comprises an electric brushless
drive motor 15 which is commutated electronically.
[0021] The coolant pump 10 has a multi-part housing 11 divided
internally by a separating can 17 into a wet section 60 and a dry
section 62. The separating can 17 is formed by a non-magnetic
plastic sleeve jacket 19 of L-shaped cross section and an
electrically conductive metal partition wall 24 which lies in a
transverse plane.
[0022] The rotor located in the wet section 60 comprises a dual
bearing shaft 12, a magnetically permanently excited motor rotor 16
and a pump rotor 14 pumping coolant from an axial coolant inlet 18
to a radial coolant outlet 20. In the dry section 62, a plurality
of stator coils 22 are arranged radially outside the motor rotor 16
and the cylindrical part of the sleeve jacket 19 and on the same
axial position, the stator coils 22 being situated on the proximal
side of the partition wall 24.
[0023] On the distal side of the partition wall 24, an electric
circuit board 28, including all the electronics for driving the
stator coils 22, is provided in a circuit board chamber 51. The
circuit board 28 lies in a transverse plane and is mounted on both
sides, wherein, on the distal side of the circuit board plate 40, a
plurality of control electronics elements 36 forming the control
electronics 36 is soldered onto conductor strips, and wherein, on
the proximal side of the circuit board 28, only a plurality of
identical power semiconductors 30, 30' are arranged which are
driven by the control electronics 36 through corresponding
through-holes 64. The power semiconductors 30, 30' may be MOSFET
transistors.
[0024] As can be seen in particular in FIG. 2, the power
semiconductors 30, 30' are mounted horizontally on the circuit
board 28, with each power semiconductor 30, 30' having a cooling
lug 34 whose surface area is larger than the corresponding surface
area of the semiconductor body 32. Each cooling lug 34, 34' is an
electric terminal of the power semiconductor and is respectively
soldered with its entire surface onto a large-surface conductor
strip 42, 42' by means of solder 35.
[0025] The proximal side 41 of the circuit board 28 is covered with
an electrically non-conductive heat conducting means 44 in the form
of a heat conducting film which has corresponding openings 45, 45'
only in the regions of the power semiconductors 30, 30'. The heat
conducting means 44 rests on the distal side 80 of the partition
wall 24 in a heat conductive manner, which partition wall 24 has
corresponding recesses 50, 50' in the region of the power
semiconductors 30, 30' and of the corresponding openings 45, 45' in
the heat conducting means 44, respectively, into which recesses 50,
50' the respective semiconductor bodies 32, 32' extend. The
recesses 50, 50' are not continuous in the axial direction so that
the partition wall 24 is completely liquid-tight.
[0026] In order to provide a good heat conduction or dissipation,
the surface area of the conductor strips 42, 42' respectively is at
least 4 to 5 times the surface area of the cooling lug 34, 34' of
the respective power semiconductor 30, 30'. As can be seen in FIG.
3, also the other terminals of the power semiconductor are soldered
to corresponding conductor strips 43.sub.1 and 43.sub.2.
[0027] The circuit board chamber 51 is closed with a cover 26.
[0028] The present invention is not limited to embodiments
described herein; reference should be had to the appended
claims.
* * * * *