U.S. patent application number 13/001161 was filed with the patent office on 2011-06-16 for electric compressor.
This patent application is currently assigned to SANDEN CORPORATION. Invention is credited to Eiji Kobayashi, Tadashi Kuribara, Kazumi Ohsato, Masanori Taguchi.
Application Number | 20110142695 13/001161 |
Document ID | / |
Family ID | 41465931 |
Filed Date | 2011-06-16 |
United States Patent
Application |
20110142695 |
Kind Code |
A1 |
Taguchi; Masanori ; et
al. |
June 16, 2011 |
ELECTRIC COMPRESSOR
Abstract
The present invention provides an electric compressor in which a
lead wire on the motor driving circuit side can be electrically
connected positively to a sealed terminal. Because the sealed
terminal is formed from a terminal body which is made of a metal
having electrical conductivity and whose end is provided with a
male threaded portion, and a joining nut made of a metal having
electrical conductivity and which is different from the material
for the terminal body, and is threadably mounted on the male
threaded portion of the terminal body, it is possible to positively
join the joining nut of a different material to the terminal body
and to positively join the lead wire of the same material as the
joining nut to the joining nut by welding, whereby it becomes
possible to electrically connect a lead wire on the driving circuit
housing chamber side positively to the sealed terminal.
Inventors: |
Taguchi; Masanori;
(Isesaki-shi, JP) ; Ohsato; Kazumi; (Isesaki-shi,
JP) ; Kobayashi; Eiji; (Isesaki-shi, JP) ;
Kuribara; Tadashi; (Isesaki-shi, JP) |
Assignee: |
SANDEN CORPORATION
Isesaki-shi
JP
|
Family ID: |
41465931 |
Appl. No.: |
13/001161 |
Filed: |
June 26, 2009 |
PCT Filed: |
June 26, 2009 |
PCT NO: |
PCT/JP2009/061749 |
371 Date: |
February 15, 2011 |
Current U.S.
Class: |
417/410.1 |
Current CPC
Class: |
F04B 39/14 20130101;
F04C 23/008 20130101; F04C 2240/803 20130101 |
Class at
Publication: |
417/410.1 |
International
Class: |
F04B 35/04 20060101
F04B035/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 2, 2008 |
JP |
2008-173462 |
Claims
1. An electric compressor comprising: a compression section for
compressing a cooling medium; a motor for driving the compression
section; a motor driving circuit for driving the motor; and a
sealed terminal which is provided in a partition wall for
partitioning a space between the motor and the motor driving
circuit and is intended for electrically connecting a lead wire on
the motor side and a lead wire on the motor driving circuit side,
wherein the sealed terminal has a terminal body which is made of a
metal having electrical conductivity and whose end is provided with
a male threaded portion, and a joining member made of a metal
having electrical conductivity and which is different from the
material for the terminal body, the joining member being provided
so as to be capable of being screwed to the male threaded portion
of the terminal body.
2. The electric compressor according to claim 1, wherein the
terminal body is made of a ferrous metal and the joining member is
made of a cuprous metal.
3. The electric compressor according to claim 1 or 2, wherein the
length along which the joining member fits over the male threaded
portion of the terminal body is not less than 0.4 times the
diameter of the male threaded portion.
4. The electric compressor according to claim 2, wherein the length
along which the joining member fits over the male threaded portion
of the terminal body is not less than 0.4 times the diameter of the
male threaded portion.
Description
TECHNICAL FIELD
[0001] The present invention relates to an electric compressor
provided with a motor for driving a compression section, a motor
driving circuit for driving the motor, and a sealed terminal for
electrically connecting the motor and the motor driving
circuit.
BACKGROUND ART
[0002] As an electric compressor of this kind, there has hitherto
been known an electric compressor which is provided with a
compression section for compressing a cooling medium, a motor for
driving the compression section, a motor driving circuit for
driving the motor, and a sealed terminal which is provided in a
partition wall for partitioning a space between the motor and the
motor driving circuit and is intended for electrically connecting a
lead wire on the motor side and a lead wire on the motor driving
circuit side (refer to Patent Document 1, for example).
PRIOR ART DOCUMENT
Patent Document
[0003] Patent Document 1: Japanese Patent Publication No.
11-324920
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
[0004] In conventional electric compressor, in connecting a lead
wire on the motor driving circuit side to a sealed terminal, the
lead wire is welded to the sealed terminal or connecting is
performed by using a connector. However, because the sealed
terminal is made of a ferrous metal and the lead wire on the motor
driving circuit side is made of a cuprous metal, in welding the
lead wire on the motor driving circuit side to the sealed terminal,
welding becomes difficult because these have different melting
points. Also, in connecting the lead wire on the motor driving
circuit side to the sealed terminal by using a connector, the
connection is accomplished only by the elastic force of the metal
material for the connector. Therefore, the area of contact between
the sealed terminal and the lead wire is small and hence this
connection method is not suitable for the application of a large
current.
[0005] The object of the present invention is to provide an
electric compressor in which a lead wire on the motor driving
circuit side can be electrically connected positively to a sealed
terminal.
Means for Solving the Problem
[0006] In order to achieve the above object, the present invention
provides an electric compressor which includes: a compression
section for compressing a cooling medium, a motor for driving the
compression section, a motor driving circuit for driving the motor,
a sealed terminal which is provided in a partition wall for
partitioning a space between the motor and the motor driving
circuit and is intended for electrically connecting a lead wire on
the motor side and a lead wire on the motor driving circuit side.
In this electric compressor, the sealed terminal has a terminal
body which is made of a metal having electrical conductivity and
whose end is provided with a male threaded portion, and a joining
member made of a metal having electrical conductivity and which is
different from the material for the terminal body. The joining
member is provided so as to be capable of being screwed to the male
threaded portion of the terminal body.
[0007] As a result of this, the joining member is screwed to the
male threaded portion of the terminal body and, therefore, it
becomes possible to positively join the joining member made of a
different material to the terminal body.
Effects of the Invention
[0008] According to the present invention, because it is possible
to positively join the joining member of a different material to
the terminal body and to positively join the lead material of the
same material as the joining member to the joining nut by welding,
it becomes possible to electrically connect a lead wire on the
motor driving circuit side positively to the sealed terminal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a side sectional view of an electric compressor in
an embodiment of the present invention.
[0010] FIG. 2 is a sectional view of a sealed terminal.
[0011] FIG. 3 is an exploded perspective view of the sealed
terminal.
[0012] FIG. 4 is a sectional view showing another example of a
sealed terminal.
PREFERRED EMBODIMENT OF THE INVENTION
[0013] FIGS. 1 to 3 show an embodiment of the present
invention.
[0014] The electric compressor of the present invention is a
scroll-type electric compressor which is provided with a housing 10
formed in cylindrical shape, a compression section 20 for
compressing a cooling medium, a motor 30 for driving the
compression section 20, and a driving circuit section 40 as a motor
driving circuit for performing the operation control of the motor
30, and for example, HFC-134a and carbon dioxide are used as a
cooling medium.
[0015] The housing 10 is composed of a first housing 11 in which
the compression section 20 is housed, a second housing 12 in which
the motor 30 is housed, and a third housing 13 in which the driving
circuit section 40 is housed.
[0016] The first housing 11 is such that one end surface thereof is
closed and the other end surface thereof is joined to one end
surface of the second housing 12. A cooling medium discharge port,
which is not shown, is provided on a peripheral surface of the
first housing 11 on the side of the one end surface.
[0017] The second housing 12 is such that one end surface thereof
is joined to the first housing 11 and the other end surface thereof
is joined to one end surface of the third housing 13.
[0018] The first housing 11 and the second housing 12 are joined
together by a bolt 14 via a center plate 25, which will be
described later, for rotatably supporting the side of one end of a
driving shaft, which will be described later, for driving the
compression section 20.
[0019] The third housing 13 is such that the side of one end
surface thereof is joined to the second housing 12 and the side of
the other end surface thereof is closed by a closing plate 15 so as
to be openable. A cooling medium suction port is provided on a
peripheral surface of the third housing 13 on the side of one end
surface thereof. Furthermore, the third housing 13 is such that the
interior thereof is partitioned by a partition wall 13a into the
side of one end surface including the cooling medium suction port
and the side of the other end surface, and the third housing 13 is
provided with a driving circuit housing chamber 13b for housing the
driving circuit section 40 and a cooling medium suction chamber 13c
in communication with the motor 30 side.
[0020] The compression section 20 has a fixed scroll member 21
fixed to the side of one end of the first housing 11 and a turning
scroll member 22 provided on the side of the other end of the first
housing 11 so as to be rotatable with respect to the fixed scroll
member 21.
[0021] The fixed scroll member 21 is formed from a member in the
shape of a disk provided so as to divide the interior of the first
housing 11, and a convoluted body 21a is provided on a surface on
the turning scroll member 22 side. In the radially middle part of
the fixed scroll member 21, there is provided a cooling medium
discharge hole 21b for discharging a cooling medium compressed in
the compression section 20. A cooling medium discharge chamber 11a
is provided between one end surface in the first housing 11 and the
fixed scroll member 21 so that a cooling medium discharged from the
cooling medium discharge port flows into the cooling medium
discharge chamber 11a.
[0022] The turning scroll member 22 is such that a convoluted body
22a is provided on the surface thereof on the fixed scroll member
21 side, and to the surface on the opposite side, there is
connected, via a driving bush 24, the side of one end of a driving
shaft 23 for transmitting the torque of the motor 30.
[0023] The driving shaft 23 is provided so as to extend along the
central axis of the second housing 12. The driving shaft 23 is
provided in such a manner that a connection 23a to the driving bush
24 is eccentric from the rotation center of the driving shaft 23.
Also, the driving shaft 23 is such that the side of one end thereof
is rotatably supported by a center plate 25 provided between the
compression section 20 and the motor 30 via a ball bearing 26 and
the side of the other end thereof is rotatably supported via a
bearing 12a (a ball bearing 27) provided on the side of the other
end surface of the second housing 12. That is, the driving shaft 23
is rotated by the motor 30 and is adapted to cause the turning
scroll member 22 to rotate on a prescribed circular orbit.
[0024] The center plate 25 is provided so as to divide the space on
the compression section 20 side and the space on the motor 30 side
in the housing 10, and there is provided a communication hole for
providing communication between the space on the compression
section 20 side and the space on the motor 30 side. Also, the
center plate 25 is provided with a flanged portion 25a extending in
the circumferential direction of an outer circumferential surface
so that the flanged portion 25a becomes sandwiched between the
first housing 11 and the second housing 12.
[0025] Between the turning scroll member 22 and the center plate
25, there are provided a rotating position regulating mechanism 28
consisting of pins which are each fixed to the turning scroll
member 22 and the center plate 25 in order to regulate the rotating
position of turning scroll member 22, and a connecting member for
connecting the pins together.
[0026] The motor 30 is composed of a three-phase induction motor
and the like and has a rotor 31 formed from a permanent magnet
fixed to the driving shaft 23, and a stator 32 which is provided so
as to surround the rotor 31 and is fixed in the second housing
12.
[0027] The driving circuit section 40 is composed of an inverter
circuit 41 having, on a substrate, power semiconductor elements 41a
as a plurality of heat generating parts, a power circuit part 42,
such as a smoothing capacitor and a noise filter, a control section
43 of a microcomputer configuration, and the like. The driving
circuit section 40 is housed in the driving circuit housing chamber
13b and is fixed in the driving circuit housing chamber 13b by use
of a molded resin 44.
[0028] This motor compressor is provided with three sealed
terminals 50 provided in the partition wall 13a positioned below
the cooling medium suction chamber 13c and intended for supplying
the electrical power from the inverter circuit 41 to the winding of
the stator 32.
[0029] Each of the sealed terminals 50 is composed of a terminal
body 51 inserted into a through hole 13d provided in the partition
wall 13a, a fixing nut 52 for fixing the terminal body 51 to the
partition wall 13a, a first insulating member 53 to be interposed
on the second housing 12 side of the partition wall 13a, a second
insulating member 54 to be interposed between the fixing nut 52 and
the partition wall 13a, a joining nut 55 which is connectably
provided to an end portion of the terminal body 51 on the driving
circuit housing chamber 13b side and to which a lead wire 45 on the
driving circuit housing chamber 13b side is joined by welding, and
an insulating cover 56 for covering the terminal body 51 from the
second housing 12 side. The lead wire 45 on the driving circuit
housing chamber 13b side is formed from a cuprous material.
[0030] The terminal body 51 is made of a ferrous metal and is such
that an end portion thereof on the second housing 12 side is
provided with a flange 51a and an end portion thereof on the
driving circuit housing chamber 13b side is provided with a male
threaded portion 51b and it is ensured that the lead wire 33 on the
motor 30 side is connected to the end portion on the second housing
12 side. The terminal body 51 is attached to the partition wall 13a
by screwing the fixing nut 52 to the male threaded portion 51b,
with the first insulating member 53 interposed on the second
housing 12 side of the partition wall 13a and the second insulating
member 54 interposed on the driving circuit housing chamber 13b
side of the partition wall 13a.
[0031] The first insulating member 53 and the second insulating
member 54 are each formed from a member having insulating
properties, such as ceramics and resins. The first insulating
member 53 are provided with three holes 53a, through each of which
three terminal bodies 51 are inserted, and one first insulating
member 53 is interposed for the three terminal bodies 51. The
second insulating member 54 is provided with a hole 54a through
which the terminal body 51 is inserted, and one second insulating
member 54 is interposed for one terminal body 51.
[0032] The joining nut 55 is made of a cuprous metal and is formed
in the shape of a cap nut which is such that the side of one end
thereof is closed. The joining nut 55 is provided with a weld 55a
so as to protrude from the side of one end and it is ensured that
the lead wire 45 on the driving circuit housing chamber 13b side is
jointed to the weld 55a by welding. The joining nut 55 is provided
in such a manner that the length along which the joining nut 55
fits over the male threaded portion 51b of the terminal body 51 is
at least not less than 0.4 times the diameter of the male threaded
portion 51b.
[0033] The insulating cover 56 is made of a material having
elasticity and insulating properties, such as rubber. The
insulating cover 56 is formed so as to cover the whole area of one
end surface of the first insulating member 53, and end portions of
the three terminal bodies 51 are covered. The insulating cover 56
are provided with three holes 56a, through each of which three lead
wires 33 on the motor 30 side are inserted.
[0034] In the electric compressor configured as described above,
the driving shaft 23 is rotated by passing a current to the motor
30, whereby in the compression section 20 the turning scroll member
22 performs a rotating motion with respect to the fixed scroll
member 21. As a result of this, a cooling medium which flows into
the housing 10 from the cooling medium suction port cools each of
power semiconductor elements 41a of the inverter circuit 41 of the
driving circuit section 40 via the partition wall 13a of the
cooling medium suction chamber 13c and cools the motor 30 by
flowing through the interior of the second housing 12. The cooling
medium which has flown through the interior of the second housing
12 flows between the turning scroll member 22 and the center plate
25 via the communication hole of the center plate 25, cools the
rotating position regulating mechanism 50 and then flows into the
compression section 20. The cooling medium compressed in the
compression section 20 flows from the cooling medium discharge hole
21b into the cooling medium discharge chamber 11a and is discharged
from the cooling medium discharge port.
[0035] In each of the sealed terminals 50, in performing the work
to connect the lead wire 45 on the driving circuit housing chamber
13b side, the joining nut 55 is screwed to the male threaded
portion 51b, with the terminal body 51 attached to the partition
wall 13a, and the lead wire 45 is joined to the weld 55a of the
joining nut 55 by welding.
[0036] As described earlier, according to the electric compressor
of this embodiment, the sealed terminal 50 has a terminal body 51
which is made of a metal having electrical conductivity and whose
end is provided with a male threaded portion 51b, and a joining nut
55 made of a metal having electrical conductivity and which is
different from the material for the terminal body 51, and is
threadably mounted on the male threaded portion 51b of the terminal
body 51. As a result of this, it is possible to positively join the
joining nut 55 of a different material to the terminal body 51 and
to positively join the lead wire 45 of the same material as the
joining nut 55 to the joining nut 55 by welding, and hence it
becomes possible to electrically connect a lead wire 45 on the
driving circuit housing chamber 13b side positively to the sealed
terminal 50.
[0037] Because the above-described terminal body 51 is made of a
ferrous metal and the joining nut 55 is made of a cuprous metal, it
is possible to easily weld the lead wire 45 made of a cuprous metal
to the joining nut 55 and it becomes possible to positively connect
the lead wire 45 made of a cuprous metal to the terminal body 51
made of a ferrous metal.
[0038] Because the length along which the joining nut 55 fits over
the male threaded portion 51b of the terminal body 51 is not less
than 0.4 times the diameter of the male threaded portion 51b, it is
possible to positively attach the joining nut 55 to the terminal
body 51 and it is possible to ensure a contact area of not less
than a prescribed contact area between the terminal body and the
joining nut 55. This enables the strength of the sealed terminal 50
to be increased and the electric resistance thereof to be
reduced.
[0039] In the above-described embodiment, a description was given
of the weld 55a which is formed on the joining nut 55 so as to
protrude from the side of one end and to which the lead wire 45 on
the driving circuit housing chamber 13b is joined by welding.
However, as shown in FIG. 4, the lead wire 45 may be joined
directly to the side of one end of the joining nut 55 by welding
without the provision of the weld 55a in the joining nut 55.
DESCRIPTION OF SYMBOLS
[0040] 13a: Partition wall 20: Compression section 30: Motor [0041]
33: Lead wire 40: Driving circuit section 45: Lead wire [0042] 50:
Sealed terminal 51: Terminal body [0043] 51b: Male threaded portion
55: Joining nut
* * * * *