U.S. patent application number 13/532033 was filed with the patent office on 2013-01-03 for motor-driven compressor.
This patent application is currently assigned to KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. Invention is credited to Hiroshi Fukasaku, Tatsuya Horiba, Hiroshi Kobayashi, Minoru Mera, Shinichi Okuyama.
Application Number | 20130004345 13/532033 |
Document ID | / |
Family ID | 46419899 |
Filed Date | 2013-01-03 |
United States Patent
Application |
20130004345 |
Kind Code |
A1 |
Horiba; Tatsuya ; et
al. |
January 3, 2013 |
MOTOR-DRIVEN COMPRESSOR
Abstract
A securing means for an insulating member that is advantageous
in improving the efficiency of assembly of a motor-driven
compressor is provided. Phase wires extending from an end face of a
stator core, which is closer to a compression mechanism, are bound
to form a phase wire bundle. The distal ends of the phase wires are
electrically connected together, so that a wire connecting portion
is formed at the distal end of the phase wire bundle. The wire
connecting portion, which serves as a neutral point, is coated with
an insulating tube made of insulating plastic. The distal end of
the insulating tube is sealed. A receiving hole is formed in the
cluster block. The insulating tube is fitted in the receiving hole
and secured to the cluster block by contacting an inner surface of
the receiving hole.
Inventors: |
Horiba; Tatsuya;
(Kariya-shi, JP) ; Okuyama; Shinichi; (Kariya-shi,
JP) ; Kobayashi; Hiroshi; (Kariya-shi, JP) ;
Mera; Minoru; (Kariya-shi, JP) ; Fukasaku;
Hiroshi; (Kariya-shi, JP) |
Assignee: |
KABUSHIKI KAISHA TOYOTA
JIDOSHOKKI
Kariya-shi
JP
|
Family ID: |
46419899 |
Appl. No.: |
13/532033 |
Filed: |
June 25, 2012 |
Current U.S.
Class: |
417/411 |
Current CPC
Class: |
F04C 2240/803 20130101;
H02K 7/14 20130101; H02K 3/50 20130101; H02K 5/225 20130101; F04C
29/0085 20130101; F04C 29/047 20130101; F01C 21/007 20130101; F04C
18/0215 20130101; F04C 23/008 20130101; F04C 2240/40 20130101 |
Class at
Publication: |
417/411 |
International
Class: |
F04B 17/03 20060101
F04B017/03; F04B 49/00 20060101 F04B049/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 28, 2011 |
JP |
2011-143211 |
Claims
1. A motor-driven compressor comprising: an electric motor having a
stator; a compression mechanism that is driven by the electric
motor to compress refrigerant; an outer shell for accommodating
therein the electric motor and the compression mechanism; a cluster
block located inside the outer shell; a phase wire bundle that is
formed by binding a plurality of phase wires extending from a
plurality of phase coils, which form the stator; and a wire
connecting portion serving as a neutral point, at which the phase
wires of the phase wire bundle are connected together, wherein the
phase wire bundle and the wire connecting portion are coated with
an insulating member, and the insulating member is secured to the
cluster block by a securing means.
2. The motor-driven compressor according to claim 1, wherein the
securing means is defined by a receiving hole formed in the cluster
block, the insulating member is fitted in the receiving hole, and
the insulating member contacts an inner surface of the receiving
hole.
3. The motor-driven compressor according to claim 2, wherein the
receiving hole has a tapering portion, the diameter of which
decreases from an entrance of the receiving hole in the direction
of depth, and a widening portion, the diameter of which increases
from the tapering portion in the direction of depth.
4. The motor-driven compressor according to claim 2, wherein the
receiving hole is formed as a through hole that extends through the
cluster block.
5. The motor-driven compressor according to claim 2, wherein the
cluster block includes connectors connected to lead wires extending
from the phase coils, and the receiving hole and the connectors are
arranged in parallel.
6. The motor-driven compressor according to claim 1, wherein the
securing means is a hook that extends from the cluster block, and
the insulating member is hooked to the hook.
7. The motor-driven compressor according to claim 1, wherein the
stator has opposite end faces, and the compression mechanism, the
electric motor, and a drive control section for the electric motor
are arranged in that order in series, and the phase wires extend
from one of the end faces of the stator that is closer to the
compression mechanism.
8. A motor-driven compressor comprising: an electric motor having a
stator; a compression mechanism that is driven by the electric
motor to compress refrigerant; an outer shell for accommodating
therein the electric motor and the compression mechanism; a cluster
block located inside the outer shell; a phase wire bundle that is
formed by binding a plurality of phase wires extending from a
plurality of phase coils, which form the stator; and a wire
connecting portion serving as a neutral point, at which the phase
wires of the phase wire bundle are connected together, wherein the
phase wire bundle and the wire connecting portion are coated with
an insulating member, and the insulating member is secured to the
cluster block by a retainer.
9. The motor-driven compressor according to claim 8, wherein the
retainer is defined by a receiving hole formed in the cluster
block, the insulating member is fitted in the receiving hole, and
the insulating member contacts an inner surface of the receiving
hole.
10. The motor-driven compressor according to claim 9, wherein the
receiving hole has a tapering portion, the diameter of which
decreases from an entrance of the receiving hole in the direction
of depth, and a widening portion, the diameter of which increases
from the tapering portion in the direction of depth.
11. The motor-driven compressor according to claim 9, wherein the
receiving hole is formed as a through hole that extends through the
cluster block.
12. The motor-driven compressor according to claim 9, wherein the
cluster block includes connectors connected to lead wires extending
from the phase coils, and the receiving hole and the connectors are
arranged in parallel.
13. The motor-driven compressor according to claim 8, wherein the
retainer is a hook that extends from the cluster block, and the
insulating member is hooked to the hook.
14. The motor-driven compressor according to claim 8, wherein the
stator has opposite end faces, and the compression mechanism, the
electric motor, and a drive control section for the electric motor
are arranged in that order in series, and the phase wires extend
from one of the end faces of the stator that is closer to the
compression mechanism.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of Japanese Patent
Application No. 2011-143211 filed Jun. 28, 2011.
BACKGROUND
[0002] The present invention relates to a motor-driven compressor
that includes a phase wire bundle formed by binding phase wires
extending from phase coils and a wire connecting portion. The wire
connecting portion serves as a neutral point, at which the phase
wires of the phase wire bundle are connected together.
[0003] Japanese Laid-Open Utility Model Publication No. 5-38368
discloses a motor-driven compressor in which lead wires extending
from the phase coils are separately connected to connecting
terminals in a cluster block. Phase wires, which form a neutral
point, are bound together to form a phase wire bundle, and the
distal ends of the wires in the phase wire bundle are collectively
coupled to a non-connecting terminal (wire connecting portion).
[0004] If located inward of the stator, a neutral point hinders
installation of other members that are to be arranged inward of the
stator. In this regard, Japanese Laid-Open Utility Model
Publication No. 5-38368 uses binding threads to tie down the
neutral point to the coil ends so that the neural point does not
sway.
[0005] In this type of motor-driven compressor, only gaseous
refrigerant (refrigerant gas) circulates within the compressor
during normal operation. However, when the operation is stopped and
refrigerant gas remaining in the housing is cooled, liquefied
refrigerant (liquid refrigerant) may remain in the housing.
[0006] If the wire connecting portion at the neutral point is
immersed in the liquid refrigerant remaining in the housing, the
wire connecting portion and the housing are conducted to each other
via the liquid refrigerant. If the motor-driven compressor starts
operating in this state, the current through the wire connecting
portion is likely to leak to the housing via the liquid
refrigerant.
[0007] In this regard, Japanese Laid-Open Patent Publication No.
2005-278289 discloses a rotating electric machine in which a
neutral point terminal is formed such that the distal ends of wires
at the neutral points do not protrude from a metal sleeve, and the
neutral point terminal is covered with an insulating cap. This
prevents short circuit between the coils and the distal ends of the
wires at the neutral point in the rotating electric machine.
However, if the neutral point terminal (wire connecting portion),
which is a neutral point, is covered with an insulating cap, liquid
refrigerant may enter the insulating cap, and the neutral point
terminal may be immersed in the liquid refrigerant. This results in
insufficient insulation resistance between the neutral point
terminal and the housing. Therefore, to prevent the neutral point
terminal from being immersed in liquid refrigerant, the insulating
cap may be elongated to ensure the insulation distance to the wire
connecting portion.
[0008] If the binding method disclosed in Japanese Laid-Open
Utility Model Publication No. 5-38368 is employed, the binding
process is troublesome and thus lowers efficiency of assembly of a
motor-driven compressor. Particularly, when an elongated insulating
cap is used to prevent liquid refrigerant from entering the
insulating cap, the insulating cap needs to be bound to the coil
end. This further lowers the assembly efficiency.
SUMMARY
[0009] Accordingly, it is an objective of the present invention to
provide a securing means for an insulating member that is
advantageous in improving the efficiency of assembly of a
motor-driven compressor.
[0010] One aspect of the present invention is a motor-driven
compressor comprising: an electric motor having a stator; a
compression mechanism that is driven by the electric motor to
compress refrigerant; an outer shell for accommodating therein the
electric motor and the compression mechanism; a cluster block
located inside the outer shell; a phase wire bundle that is formed
by binding a plurality of phase wires extending from a plurality of
phase coils, which form the stator; and a wire connecting portion
serving as a neutral point, at which the phase wires of the phase
wire bundle are connected together, wherein the phase wire bundle
and the wire connecting portion are coated with an insulating
member, and the insulating member is secured to the cluster block
by a securing means.
[0011] Other aspects and advantages of the invention will become
apparent from the following description, taken in conjunction with
the accompanying drawings, illustrating by way of example the
principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention, together with objects and advantages thereof,
may best be understood by reference to the following description of
the presently preferred embodiments together with the accompanying
drawings in which:
[0013] FIG. 1 is a cross-sectional side view illustrating a
motor-driven compressor according to a first embodiment;
[0014] FIG. 2 is a cross-sectional view taken along line 2-2 of
FIG. 1;
[0015] FIG. 3 is a partial enlarged plan view illustrating the
motor-driven compressor according the first embodiment;
[0016] FIG. 4 is a partial enlarged plan view illustrating a
motor-driven compressor according a second embodiment;
[0017] FIG. 5a is a partial enlarged plan view illustrating a
motor-driven compressor according a third embodiment; and
[0018] FIG. 5b is a partial cross-sectional view illustrating a
motor-driven compressor according a third embodiment.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0019] A first embodiment of the present invention will now be
described with reference to FIGS. 1 to 3.
[0020] A motor-driven compressor 10 shown in FIG. 1 is a scroll
type motor-driven compressor, which includes a compression
mechanism P, which draws in and discharges refrigerant, an electric
motor M, and an inverter 28, which is a drive control section for
the electric motor M. The compression mechanism P, the electric
motor M, and the inverter 28 are arranged in series in that order
from the front of the motor-driven compressor 10 (the left side as
viewed in FIG. 1) to the rear (the right side as viewed in FIG.
1).
[0021] An outer shell 11 of the motor-driven compressor 10 is
formed by a motor housing 12 and a front housing 13 coupled to the
front end of the motor housing 12. The electric motor M is located
in the motor housing 12. The electric motor M includes a rotor 14,
a stator 15 and a rotary shaft 33. The rotor 14 is fixed to the
rotary shaft 33, and the stator 15 is securely fitted to the inner
circumferential surface of the motor housing 12. The compression
mechanism P includes a movable scroll 16 and a fixed scroll 17. The
movable scroll 16 is accommodated between the fixed scroll 17 and a
support block 34, which is fixed to the motor housing 12. The
movable scroll 16 is caused to orbit by rotation of the rotary
shaft 33. A compression chamber 18 is defined between the movable
scroll 16 and the fixed scroll 17. As the movable scroll 16 orbits,
the volume of the compression chamber 18 is changed so that
refrigerant is drawn in and discharged.
[0022] The motor housing 12 has an inlet port 121 connected to an
external refrigerant circuit 19. Refrigerant (gas) is drawn into
the motor housing 12 from the external refrigerant circuit 19 via
the inlet port 121. Orbiting motion (suction motion) of the movable
scroll 16 causes refrigerant guided into the motor housing 12 to be
drawn into the compression chambers 18 through passages (not shown)
between the inner circumferential surface of the motor housing 12
and the outer circumferential surface of the stator 15. The
refrigerant gas in the compression chambers 18 is compressed by
orbiting motion of the movable scroll 16 (discharge operation), and
is discharged into a discharge chamber 22 in the front housing 13
through a discharge port 171 while flexing a discharge valve 21.
Refrigerant that has entered the discharge chamber 22 flows out to
the external refrigerant circuit 19 through a delivery port 131
formed in the front housing 13, and is recirculated to the motor
housing 12.
[0023] As shown in FIG. 2, the stator 15 of the electric motor M
includes an annular stator core 23, and an U-phase coil 24U, a
V-phase coil 24V and a W-phase coil 24W, which are wound about the
stator core 23.
[0024] FIG. 1 shows a front coil end 241 and a rear coil end 242.
The coil end 241 protrudes from a front end face 231 of the stator
core 23, and the coil end 242 protrudes from a rear end face 232 of
the stator core 23.
[0025] The rotor 14 of the electric motor M includes a rotor core
25 and permanent magnets 26, which are embedded in the rotor core
25. A shaft hole 251 extends through a center of the rotor core 25,
and the rotary shaft 33 is inserted into and fixed to the shaft
hole 251.
[0026] A cover 27 is secured to the rear end face of the motor
housing 12 (the right end face as viewed in FIG. 1). The inverter
28, which is a drive control section, is located in the cover 27.
An insertion hole 29 is formed in the rear end face of the motor
housing 12, which is covered with the cover 27. A holding member 30
is fitted in and fixed to the insertion hole 29.
[0027] As shown in FIG. 3, a plurality of conductive pins 31U, 31V,
31W are passed through and held by the holding member 30. Outer
ends of the conductive pins 31U, 31V, 31W, which are protruding
outside from the outer shell 11 (the motor housing 12), are
connected to the inverter 28 [see FIG. 1] via non-illustrated
conductive wires.
[0028] As shown in FIG. 2, a cluster block 32 made of insulating
plastic is secured to an outer circumferential surface 230 of the
stator core 23. The cluster block 32 has a recess 320, which has a
shape corresponding to the outer circumferential surface 230 of the
stator core 23. The cluster block 32 is attached to the
circumferential surface 230 of the stator core 23 by a
non-illustrated attaching means. In this state, the recess 320
contacts the arcuate outer circumferential surface of the stator
core 23.
[0029] As shown in FIG. 3, the cluster block 32 accommodates a
U-phase connector 321U, a V-phase connector 321V, and a W-phase
connector 321W, which are arranged in parallel with each other. The
conductive pins 31U, 31V, 31W are connected to the connectors 321U,
321V, 321W, respectively.
[0030] As shown in FIG. 2, a lead wire 240U, which is continuous
with the U-phase coil 24U, extends from the front coil end 241 of
the stator core 23, and is then connected to the U-phase connector
321U. A lead wire 240V, which is continuous with the V-phase coil
24V, extends from the coil end 241, and is then connected to the
V-phase connector 321V. A lead wire 240W, which is continuous with
the W-phase coil 24W, extends from the coil end 241, and is then
connected to the W-phase connector 321W. The lead wires 240U, 240V,
240W are all coated with a non-illustrated insulating tube.
[0031] As shown in FIG. 3, the lead wire 240U and the conductive
pin 31U are electrically connected to each other through the
U-phase connector 321U. The lead wire 240V and the conductive pin
31V are electrically connected to each other through the V-phase
connector 321V. The lead wire 240W and the conductive pin 31W are
electrically connected to each other through the W-phase connector
321W.
[0032] When the inverter 28 shown in FIG. 1 supplies electricity to
the coils 24U, 24V, 24W via the conductive pins 31U, 31V, 31W, the
connectors 321U, 321V, 321W, and the lead wires 240U, 240V, 240W,
the rotor 14 and the rotary shaft 33 rotate integrally inside the
stator core 23 (inward of the inner circumferential surface 233 of
the stator core 23).
[0033] As shown in FIG. 2, a phase wire 35U extending from the
U-phase coil 24U, a phase wire 35V extending from the V-phase coil
24V, and a phase wire 35W extending from the W-phase coil 24W are
bound to form a phase wire bundle 36. The phase wires 35U, 35V, 35W
extend from the coil end 241 on the end face 231 of the stator core
23, which is closer to the compression mechanism P.
[0034] As illustrated in FIG. 3, the distal ends of the phase wires
35U, 35V, 35W, which form the phase wire bundle 36, are
electrically connected together, so that a wire connecting portion
361 is formed at the distal end of the phase wire bundle 36. The
wire connecting portion 361, which serves as a neutral point, is
coated with an insulating tube 37 made of insulating plastic. The
distal end of the insulating tube 37 is sealed.
[0035] As shown in FIG. 3, the cluster block 32 has a receiving
hole 38, which serves as a securing means, or a retainer. The
receiving hole 38 is parallel with the connectors 321U, 321V, 321W.
The insulating tube 37, which functions as an insulating member, is
fitted in the receiving hole 38. More specifically, the insulating
tube 37 is inserted from an entrance 381 of the receiving hole 38
that is located on an end face 322 of the cluster block 32 facing
the compression mechanism P. The insulating tube 37 is secured to
the cluster block 32 by contacting an inner surface 382 of the
receiving hole 38.
[0036] Operation of the first embodiment will now be described.
[0037] The insulating tube 37 is fitted in the receiving hole 38 to
reach the farthest point possible from the entrance 381 of the
receiving hole 38. Accordingly, the phase wires 35U, 35V, 35W are
extended without sagging. This prevents the phase wires 35U, 35V,
35W from being displaced to positions inward of the stator core 23.
Since the phase wires 35U, 35V, 35W extend from the coil end 241,
the lead wires 240U, 240V, 240W are not moved to positions inward
of the stator core 23.
[0038] Since the insulating tube 37 is fitted in and held by the
receiving hole 38, the insulating tube 37 is unlikely to be
detached from the phase wire bundle 36.
[0039] The first embodiment has the advantages described below.
[0040] (1) With the insulating tube 37 fitted in the receiving hole
38, the phase wire bundle 36 is prevented from swaying. That is,
the phase wire bundle 36 is prevented from being moved to a
position inward of the stator core 23 without using a binding
thread. Thus, installation of members that are to be arranged in
the stator core 23, such as the rotor core 25 and the support block
34, is not hindered.
[0041] (2) The insulating tube 37 is secured to the cluster block
32 simply by fitting the insulating tube 37 in the receiving hole
38. Such fitting operation is easy, which improves the efficiency
of assembly of the motor-driven compressor 10. Since the inner
surface 382 of the receiving hole 38 contacts the insulating tube
37, the insulating tube 37 is not easily detached from the
receiving hole 38. In other words, the insulating tube 37 is
reliably secured to the cluster block 32.
[0042] (3) The receiving hole 38 can be easily formed in the
cluster block 32, which is made of insulating plastic. Accordingly,
the structure for securing the insulating tube 37 to the cluster
block 32 is simplified.
[0043] (4) Since the receiving hole 38 is a through hole, the phase
wire bundle 36 can be extended as much as possible so that the
phase wire bundle 36 is reliably prevented from sagging.
[0044] (5) Since the compression mechanism P, the electric motor M,
and the inverter 28 are arranged in that order in series, the phase
wires 35U, 35V, 35W and the lead wires 240U, 240V, 240W extend from
the end face 231 of the stator core 23, which is closer to the
compression mechanism P. Therefore, no electrical wire connecting
needs to be performed in the narrow clearance between the electric
motor M and the inverter 28 (in the example of FIG. 1, the
clearance between the end face 232 and the rear end face of the
motor housing 12). That is, since the compression mechanism P, the
electric motor M, and the inverter 28 are arranged in that order in
series, wire connecting can be easily performed. This improves the
efficiency of assembly of the motor-driven compressor 10.
[0045] The present invention, in which the insulating tube 37 is
secured to the cluster block 32, is particularly suitable for the
motor-driven compressor 10, which has components arranged in series
and improves the assembly efficiency.
[0046] (6) The phase wire bundle 36 and the wire connecting portion
361 are coated with the insulating tube 37. Therefore, even if
liquid refrigerant is pooled in the motor-driven compressor 10, the
wire connecting portion 361 is prevented from being immersed in the
liquid refrigerant.
[0047] A second embodiment will now be described with reference to
FIG. 4. The same reference numerals are given to those components
that are the same as the corresponding components of the first
embodiment, and detailed explanations are omitted.
[0048] An inner surface 382 of a receiving hole 38A, which serves
as a securing means, or a retainer, has a tapering portion 39 and a
widening portion 40. The tapering portion 39 has a diameter that
decreases from the entrance 381 in the direction of depth (from the
side corresponding to the coil end 241 toward the coil end 242).
The widening portion 40 has a diameter that increases in the
direction of depth.
[0049] The boundary between the tapering portion 39 and the
widening portion 40 is a smallest diameter portion 391 of the
tapering portion 39. The insulating tube 37 is compressed in an
area including the smallest diameter portion 391. Such a
compressing structure further reliably prevents the insulating tube
37 from coming out of the receiving hole 38A. That is, the
insulating tube 37 is further reliably secured to the cluster block
32.
[0050] Since the insulating tube 37 is compressed in an area
including the smallest diameter portion 391 of the tapering portion
39, liquid refrigerant is reliably prevented from entering the
insulating tube 37.
[0051] A third embodiment will now be described with reference to
FIGS. 5(a) and 5(b). The same reference numerals are given to those
components that are the same as the corresponding components of the
first embodiment, and detailed explanations are omitted.
[0052] A hook 41 serving as a securing means, or a retainer,
extends from a side surface 323 of the cluster block 32. The hook
41 is formed integrally with the cluster block 32. The insulating
tube 37 is hooked to and fastened by the hook 41.
[0053] The insulating tube 37 is secured to the cluster block 32
simply by being hooked to the hook 41. Such hooking operation is
easy, which improves the efficiency of assembly of the motor-driven
compressor 10. Also, the hook 41 is easily formed in the cluster
block 32, which is made of insulating plastic. Accordingly, the
structure for hooking the insulating tube 37 to the hook 41 is
simplified.
[0054] Since the insulating tube 37 is fastened by the hook 41,
liquid refrigerant is reliably prevented from entering the
insulating tube 37.
[0055] The above illustrated embodiments may be modified as
follows.
[0056] In the first and second embodiments, the insulating tube 37
may be fixed in the receiving hole 38, 38A using adhesive.
[0057] In the first and second embodiments, the insulating tube 37
may be fixed in the receiving hole 38, 38A through ultrasonic
welding.
[0058] The insulating member may be formed by winding an insulating
tape around the phase wire bundle 36.
[0059] The receiving hole does not need to be a through hole.
[0060] The inverter 28 (the drive control section) may be located
on the outer circumference of the electric motor M.
* * * * *