U.S. patent application number 13/128140 was filed with the patent office on 2011-09-01 for inverter-integrated electric compressor.
This patent application is currently assigned to Sanden Corporation. Invention is credited to Tadashi Kuribara, Kazumi Ohsato, Atsushi Saito, Makoto Shibuya.
Application Number | 20110211981 13/128140 |
Document ID | / |
Family ID | 42152737 |
Filed Date | 2011-09-01 |
United States Patent
Application |
20110211981 |
Kind Code |
A1 |
Saito; Atsushi ; et
al. |
September 1, 2011 |
Inverter-Integrated Electric Compressor
Abstract
Provided is an inverter-integrated electric compressor excellent
in joining strength and joining reliability at electrical joint. An
inverter-integrated electric compressor wherein a motor is
incorporated and a motor drive circuit including the inverter is
surrounded by a compressor housing, characterized in that a bus bar
joint section at which bus bars are electrically joined together is
provided in the motor drive circuit, and a tip of at least one of
the bus bars, the tip being located at the bus bar joint section,
is split into small joining sections.
Inventors: |
Saito; Atsushi; (Gunma,
JP) ; Shibuya; Makoto; (Gunma, JP) ; Ohsato;
Kazumi; (Gunma, JP) ; Kuribara; Tadashi;
(Gunma, JP) |
Assignee: |
Sanden Corporation
Gunma
JP
|
Family ID: |
42152737 |
Appl. No.: |
13/128140 |
Filed: |
November 6, 2009 |
PCT Filed: |
November 6, 2009 |
PCT NO: |
PCT/JP2009/005924 |
371 Date: |
May 6, 2011 |
Current U.S.
Class: |
417/410.1 |
Current CPC
Class: |
F04C 23/02 20130101;
F04C 29/0085 20130101; F04C 2240/30 20130101; F04C 23/008 20130101;
F04C 18/0215 20130101; F04C 2240/403 20130101; F04C 2270/07
20130101; F04C 2240/40 20130101; F04C 2240/808 20130101; F04C
2240/803 20130101; F04B 39/121 20130101; F04C 2270/10 20130101 |
Class at
Publication: |
417/410.1 |
International
Class: |
F04B 17/03 20060101
F04B017/03 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 6, 2008 |
JP |
2008285823 |
Claims
1. An inverter-integrated electric compressor, wherein a motor is
incorporated and a motor drive circuit including an inverter is
provided in a housing space surrounded by a compressor housing,
wherein a bus bar joint section at which bus bars are joined
together to connect electrically is provided in said motor drive
circuit, and that a tip, which is located at said bus bar joint
section, of at least one of said bus bars is split into small
joining sections.
2. The inverter-integrated electric compressor according to claim
1, wherein said tips of both bus bars are provided with small
joining sections.
3. The inverter-integrated electric compressor according to claim
1, wherein at least one of said bus bars is provided as standing up
from a board of said motor drive circuit.
4. The inverter-integrated electric compressor according to claim
1, wherein at least one of said bus bars is provided on an IPM.
5. The inverter-integrated electric compressor according to claim
1, wherein said joining is performed by a TIG welding.
6. The inverter-integrated electric compressor according to claim
1, wherein the compressor is a compressor used for automotive air
conditioning systems.
7. The inverter-integrated electric compressor according to claim
6, wherein said compressor is mounted to an automotive engine.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to an inverter-integrated
electric compressor in which a motor drive circuit including an
inverter is mounted in a compressor, and specifically relates to an
inverter-integrated electric compressor which is designed to
improve the working efficiency for mounting an electronic component
such as IPM, which is weak to thermal stress, in the motor drive
circuit.
BACKGROUND ART OF THE INVENTION
[0002] As disclosed in Patent document 1, known is a structure of
an inverter-integrated electric compressor in which a motor drive
circuit including an inverter is mounted in a compressor, where the
motor drive circuit is coated with insulative resin coating
material, and where the motor drive circuit, lead wires and
connection terminals are provided in a closed space surrounded by a
metal wall. In the motor drive circuit of the compressor, used are
electronic components, such as IPM (Intelligent Power Module)
having an inverter function and being weak to heat.
[0003] In addition, known is a joint structure body which consists
of joined members configuring an electric circuit, wherein a joint
has a plurality of joining spots, as shown in Patent document 2.
Such a joining structure body is provided with a plurality of
joining spots at a joint section, so that the joint section is
ensured to have sufficient strength.
PRIOR ART DOCUMENTS
Patent documents
[0004] Patent document 1: JP2008-202564-A [0005] Patent document 2:
JP2004-185953-A
SUMMARY OF THE INVENTION
Problems to be solved by the Invention
[0006] In the inverter-integrated electric compressor which is
disclosed in Patent document 1, terminals such as a bus bar can be
used at an electrical joint. In such a case, the terminals can be
connected to each other with bolts or screws, and alternatively can
be connected to each other by welding. However in a case where
components have to be mounted in a predetermined space, the welding
may be the only method applicable.
[0007] However, because an inverter-integrated electric compressor
requires electric current greater than general compressors, when
the contact resistance at the joint section is comparatively high,
heat generation from the joint section might adversely affect
various devices. In addition, when a compressor is mounted to an
automotive engine as being used in an air conditioning system for
vehicles, the joint section is required to have joining strength
and joining reliability enough to endure a severe condition of high
temperature in an engine room.
[0008] Therefore, being focused on the above described problems, an
object of the present invention is to provide an
inverter-integrated electric compressor, which is excellent in
joining strength and joining reliability at the electrical
joint.
Means for Solving the Problems
[0009] To achieve the above described object, an
inverter-integrated electric compressor according to the present
invention is an inverter-integrated electric compressor, wherein a
motor is incorporated and a motor drive circuit including an
inverter is provided in a housing space surrounded by a compressor
housing, characterized in that a bus bar joint section at which bus
bars are joined together to connect electrically is provided in the
motor drive circuit, and a tip, which is located at the bus bar
joint section, of at least one of the bus bars is split into small
joining sections.
[0010] Because the tip, which is located at the bus bar joint
section connecting the bus bars electrically, of at least one of
the bus bars is split into small joining sections in the
inverter-integrated electric compressor according to the present
invention, each other's bus bar can be joined at a plurality of
spots, so that the connection strength and the connection
reliability can be ensured. In addition, because they can contact
with a large contact area, contact resistance at the joint section
can be reduced. Further, in employing a joint method such as
welding which requires to be heated, thermal stress to electronic
components can be reduced in the present invention more than in a
conventional method where the total area of welded spots are
concentrated to one spot. In the present invention, welding is
performed as dispersed to a plurality of welded spots, so that
energy (Voltage.times.Current.times.Weld time, for example) applied
in the weld time can be suppressed. Furthermore, because welded
spots are dispersed and therefore each welded area is
segmentalized, a welding machine and a clamping jig which are used
in welding can be downsized, so that the productivity of
compressors is improved.
[0011] In the present invention, it is possible that the tips of
both bus bars are provided with small joining sections. Because the
tips of both bus bars are provided with similar small joining
sections, relative positioning between bus bars can be easily
performed. In a case where the bus bar of the inverter-integrated
electric compressor of the present invention is welded by a TIG
welding, if the tips of both bus bars are provided with small
joining sections, the arc for the TIG welding can be accurately
jetted toward the spot to be welded, so that the connection
reliability at the welded spot is ensured.
[0012] Because the motor drive circuit board is often provided with
a lot of electronic components which are weak to thermal stress,
the present invention makes it possible to effectively achieve
reducing thermal load in a case where at least one of the bus bars
is connected to a board of the motor drive circuit. As well,
because IPM is weak to thermal stress, the present invention makes
it possible to effectively achieve reducing thermal load in a case
where at least one of bus bars is provided on an IPM. Furthermore,
it is preferable that at least one of the bus bars is provided as
standing up from the board of the motor drive circuit. Thus the bus
bar is provided as standing up from the board, so as to make it
easy to perform relative positioning with the bus bar provided in a
member, such as a case member, which houses the motor drive
circuit.
[0013] The inverter-integrated electric compressor according to the
present invention is applicable to all types of compressors
substantially, and specifically, is suitably used as a compressor
for automotive air conditioning systems which are often installed
in a narrow space and are sensitive to thermal stress. In addition,
when the compressor is mounted to an automotive engine, the joint
section can be given joining strength and joining reliability
enough to endure a severe condition of high temperature in an
engine room.
Effect according to the Invention
[0014] In the inverter-integrated electric compressor according to
the present invention, the tip of at least one of the bus bars is
split into small joining sections at the bus bar joint section, so
that the connection strength and the connection reliability can be
improved. Further, because the joint section can contact with a
large contact area, contact resistance is reduced so as to suppress
heat generation even when great electric current flows into the
joint section under operation of the compressor. Furthermore,
because the tips of both bus bars are segmentalized into small
joining sections, relative positioning between the bus bars can be
easily performed and the productivity of the compressor can be
improved.
BRIEF EXPLANATION OF THE DRAWINGS
[0015] FIG. 1 is a schematic longitudinal sectional view, showing a
basic configuration of an inverter-integrated electric compressor
according to an embodiment of the present invention.
[0016] FIG. 2 is a configuration diagram which shows like an
electric circuit an air conditioning control mechanism including
the compressor in FIG. 1.
[0017] FIG. 3 is a perspective view showing a connection state
between a case member, which houses motor drive circuit 21 shown in
FIG. 1, and IPM 25 shown in FIG. 1.
[0018] FIG. 4 is a partial enlarged perspective view, showing
enlarged joint sections of bus bars 60, 70 shown in FIG. 3.
EMBODIMENTS FOR CARRYING OUT THE INVENTION
[0019] Hereinafter, desirable embodiments will be explained as
referring to figures.
[0020] FIG. 1 shows a scroll-type electric compressor for
automotive air conditioning systems, as a basic configuration of
inverter-integrated electric compressor 1 according to an
embodiment of the present invention. In FIG. 1, symbol 2 implies a
compression mechanism consisting of fixed scroll 3 and movable
scroll 4. Movable scroll 4 is swung relative to fixed scroll 3
while its rotation is prevented with ball coupling 5. Motor 7 is
incorporated in compressor housing (center housing) 6, and main
shaft 8 (rotation shaft) is driven to rotate by built-in motor 7.
The rotational movement of main shaft 8 is converted into the
orbital swinging movement of movable scroll 4, through eccentric
pin 9 and eccentric bush 10 which is rotatably engaged therewith.
In this embodiment, compressor housing (front housing) 12 is
provided with suction port 11 for sucking refrigerant as fluid to
be compressed. Sucked refrigerant is led to compression mechanism 2
through a placement part of motor 7. The refrigerant which has been
compressed with compression mechanism 2 is delivered to an external
circuit, through discharge hole 13, discharge chamber 14 and
discharge port 16 which is provided in compressor housing (rear
housing) 15.
[0021] Motor drive circuit 21 for motor 7 is provided in compressor
housing 12 (front housing). In more detail, motor drive circuit 21
is provided at the external side of partition wall 22 which is
formed in compressor housing 12 against the side of refrigerant
suction passageway. Motor drive circuit 21 supplies electricity
through seal terminal 23 (an output terminal of motor drive circuit
21), which is attached thereto by penetrating partition wall 22,
and lead wire 24 to motor 7, while the refrigerant suction
passageway side and the side of motor drive circuit 21 are sealed
in the placement part of motor 7. Because motor drive circuit 21 is
provided at the external side of partition wall 22, at least one
part of electric components including motor drive circuit 21 can be
cooled with sucked refrigerant by heat exchange.
[0022] Motor drive circuit 21 includes IPM (Intelligent Power
Module) 25 having inverter function and control circuit 26, and
electric components such as capacitor 27 are provided either
integrally with it or separately from it. Motor drive circuit 21 is
connected to an external power supply (not shown) through connector
28 as an input terminal. The aperture side to the outside of
compressor housing 12, which mounts these electric components
including motor drive circuit 21, is covered as sealed with lid
member 29, and these electric components are protected by lid
member 29.
[0023] The above-described configuration can be shown like an
electric circuit, as in FIG. 2. As shown in FIG. 2, electric
compressor 1 is provided with motor drive circuit 21. Output
electric power is supplied from motor drive circuit 21, through
seal terminal 23 and lead wire 24, to each motor wire wrap 41 of
built-in motor 7, so that motor 7 is driven to rotate and
compression is performed by compression mechanism 2. Motor drive
circuit 21 has high voltage circuit 30 for motor drive and low
voltage circuit 45 for control with motor control circuit 44 to
control each power element 43 (switching element) of inverter 42 in
high voltage circuit 30 for motor drive and low voltage circuit 45
for control is comprised in control circuit 26. The electric power
is supplied from external power supply 46 (e.g. battery) through
connector 47 for high voltage into high voltage circuit 30 for
motor drive, and then supplied through noise filter 37 and
capacitor 27 for smoothing to inverter 42. Direct current, which is
input from external power supply 46, is converted into
pseudo-triphase current by inverter 42, and then supplied to motor
7. For example, low voltage electric power is supplied to motor
control circuit 44 through connector 49 for control signal from air
conditioning control device 48 of a vehicle. In FIG. 2, connector
49 for control signal and connector 47 for high voltage are
illustrated at positions apart from each other, but actually, are
mounted in the same connector 28 shown in FIG. 1. Shield plate 31,
which is fixed to control circuit 26, is interposed between high
voltage circuit 30 for motor drive and control circuit 26 with low
voltage circuit 45 for control, and it covers over high voltage
circuit 30 for motor drive as much as possible so as to block the
effect of noise on the side of low voltage circuit 45 for control
from high voltage circuit 30 for motor drive.
[0024] FIG. 3 is a perspective view, showing a state where
electronic components, such as IPM 25, are connected to case member
58 which houses motor drive circuit 21 of the compressor shown in
FIG. 1. Bus bar 60 as an electrical connection terminal provided on
an end face of case member 58 is connected electrically by TIG
welding to bus bar 70 provided in IPM 25. In addition, a part of
case member 58 is perforated along bus bar 80, so as to form
component affixing hole 59. A coil component (not shown) for noise
removal of motor drive circuit 21 is inserted into component
affixing hole 59, and is electrically connected to bus bar 90,
which is provided in the coil component, by TIG welding. Bus bars
80, 90 are welded on small joining sections 81, 91 each having
three split tips. Besides, capacitor 27 and a board of motor drive
circuit 21 can be exemplified as various electronic components to
be inserted in component affixing hole 59.
[0025] FIG. 4 is a partial enlarged perspective view, showing
enlarged joint sections of bus bars 60, 70 shown in FIG. 3. In
order to facilitate visualization, case member 58 and IPM 25 in
FIG. 3 have not been illustrated. Bus bars 60, 70 are welded on
small joining sections 61, 71, which are formed by dividing tips of
bus bar 60 and bus bar 70. Because the tips of bus bar are divided
into small joining sections, the arc for the TIG welding can be
accurately jetted toward the spot to be welded, and both high
connection strength and connection as well as low contact
resistance can be performed.
INDUSTRIAL APPLICATIONS OF THE INVENTION
[0026] The inverter-integrated electric compressor according to the
present invention is applicable to all types of compressors
substantially, and specifically suitably used as a compressor for
an automotive air conditioning system which is mounted in a narrow
space and is sensitive to thermal stress.
EXPLANATION OF SYMBOLS
[0027] 1: inverter-integrated electric compressor [0028] 2:
compression mechanism [0029] 3: fixed scroll [0030] 4: movable
scroll [0031] 5: ball coupling [0032] 6: compressor housing (center
housing) [0033] 7: motor [0034] 8: main shaft [0035] 9: eccentric
pin [0036] 10: eccentric bush [0037] 11: suction port [0038] 12:
compressor housing (front housing) [0039] 13: discharge hole [0040]
14: discharges chamber [0041] 15: compressor housing (rear housing)
[0042] 16: discharge port [0043] 21: motor drive circuit [0044] 22:
partition wall [0045] 23: seal terminal [0046] 24: lead wire [0047]
25: IPM [0048] 26: control circuit [0049] 27: capacitor [0050] 28:
connector [0051] 29: lid member [0052] 30: high voltage circuit for
motor drive [0053] 31: shield plate [0054] 37: noise filter [0055]
41: motor wire wrap [0056] 42: inverter [0057] 43: power element
[0058] 44: motor control circuit [0059] 45: low voltage circuit for
control [0060] 46: external power supply [0061] 47: connector for
high voltage [0062] 48: air conditioning system [0063] 49:
connector for control signal [0064] 58: case member [0065] 59:
component affixing hole [0066] 60, 70, 80, 90: bus bar [0067] 61,
71, 81, 91: small joining section
* * * * *