U.S. patent application number 12/442493 was filed with the patent office on 2010-03-25 for electric compressor.
This patent application is currently assigned to Calsonic Kansei Corporation. Invention is credited to Yutaka Satou, Masaki Watanabe, Toshiharu Watanabe.
Application Number | 20100074773 12/442493 |
Document ID | / |
Family ID | 39709975 |
Filed Date | 2010-03-25 |
United States Patent
Application |
20100074773 |
Kind Code |
A1 |
Watanabe; Toshiharu ; et
al. |
March 25, 2010 |
ELECTRIC COMPRESSOR
Abstract
A lubricating oil reservoir provided at the bottom of a housing
is placed under the compression mechanism or electric motor in the
vicinity of the mounting bracket provided on the lower outside of a
middle case. The lubricating oil reservoir can be provided
efficiently using dead space formed under the compression mechanism
in the housing, and the rigidity of the mounting bracket can secure
the strength of the lubricating oil reservoir.
Inventors: |
Watanabe; Toshiharu;
(Tochigi, JP) ; Satou; Yutaka; (Saitama, JP)
; Watanabe; Masaki; (Tochigi, JP) |
Correspondence
Address: |
FOLEY AND LARDNER LLP;SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
Calsonic Kansei Corporation
|
Family ID: |
39709975 |
Appl. No.: |
12/442493 |
Filed: |
February 15, 2008 |
PCT Filed: |
February 15, 2008 |
PCT NO: |
PCT/JP2008/052513 |
371 Date: |
March 22, 2009 |
Current U.S.
Class: |
417/410.3 ;
417/410.1 |
Current CPC
Class: |
F01C 21/10 20130101;
F04C 23/00 20130101; F04C 2240/808 20130101; F04C 23/008 20130101;
F04C 18/3441 20130101; F04C 2240/803 20130101; F04C 29/028
20130101 |
Class at
Publication: |
417/410.3 ;
417/410.1 |
International
Class: |
F04C 29/02 20060101
F04C029/02; F04B 39/02 20060101 F04B039/02 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 20, 2007 |
JP |
2007 039778 |
Jul 12, 2007 |
JP |
2007 183105 |
Claims
1. An electric compressor comprising: a housing accommodating at
least a compression mechanism and an electric motor driving the
compression mechanism; and a mounting bracket protruded at least at
lower outside of the housing, wherein a lubricating oil reservoir
provided at the bottom of the housing is placed under the
compression mechanism or electric motor in the vicinity of the
mounting bracket.
2. The electric compressor according to claim 1, further
comprising: a discharge port opened in the housing, through which
fluid compressed by the compression mechanism is discharged to the
outside of the housing; a pressure introduction path allowing the
discharge port and lubricating oil reservoir to communicate with
each other; and a lubricating oil feeding path allowing the
lubricating oil reservoir and a sliding portion of the compression
mechanism to communicate with each other.
Description
TECHNICAL FIELD
[0001] The present invention relates to an electric compressor
integrally including a compression mechanism and an electric
motor.
BACKGROUND ART
[0002] In one of conventionally known electric compressors, a
compression mechanism and an electric motor driving the same are
accommodated in a housing, at the bottom of which a reservoir of
lubricating oil for lubrication of required lubrication portions of
the compression mechanism is provided.
[0003] Patent Literature 1 discloses a transverse-mounted electric
compressor. In such a structure, for example, part of the housing
accommodating the electric motor is extended axially outward, and
the lubricating oil reservoir is provided for the extended part.
The lubricating oil within the reservoir is supplied to the
required lubrication portions of the compression mechanism, and the
lubricating oil is returned to the lubricating oil reservoir.
[0004] However, in such a conventional electric compressor, the
lubricating oil reservoir is provided for the axially extended part
of the housing. The housing is inevitably elongated in the axial
direction, thus resulting in an increase in size of the electric
compressor.
[0005] The lubricating oil reservoir is provided at the portion of
the housing just extended. Accordingly, it is necessary to employ a
reinforcing structure, such as increasing wall thickness of the
housing or providing a reinforcement rib, in order to reinforce the
lubricating oil reservoir, thus causing an increase in weight.
[0006] An object of the present invention is to provide an electric
compressor in which the lubricating oil reservoir can be reinforced
using an existing constituent member while the housing is prevented
from being elongated in the axial direction.
Patent Literature 1: Japanese Patent Laid-open Publication No.
6-2684
DISCLOSURE OF THE INVENTION
[0007] In the present invention, an electric compressor includes: a
housing accommodating at least a compression mechanism and an
electric motor driving the compression mechanism; and a mounting
bracket protruded at least at lower outside of the housing, in
which a lubricating oil reservoir provided at the bottom of the
housing is placed under the compression mechanism or electric motor
in the vicinity of the mounting bracket.
[0008] Moreover, in the present invention, the electric compressor
further includes: a discharge port opened in the housing, through
which fluid compressed by the compression mechanism is discharged
to the outside of the housing; a pressure introduction path
allowing the discharge port and lubricating oil reservoir to
communicate with each other; and a lubricating oil feeding path
allowing the lubricating oil reservoir and a sliding portion of the
compression mechanism to communicate with each other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of a whole electric compressor
according to a first embodiment of the present invention.
[0010] FIG. 2 is a longitudinal section view of the electric
compressor according to the first embodiment of the present
invention.
[0011] FIG. 3 is a longitudinal section view of an electric
compressor according to a second embodiment of the present
invention.
[0012] FIG. 4 is a cross section view taken along a line IV-IV of
FIG. 3.
[0013] FIG. 5 is a rear view of the electric compressor according
to the second embodiment of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0014] Hereinafter, a description is given of preferred embodiments
of the present invention in detail with reference to the drawings.
The embodiments are examples of an electric compressor applied to a
refrigeration cycle of an air conditioner of a vehicle. In this
case, fluid compressed by the electric compressor is a refrigerant
of the refrigeration cycle.
First Embodiment
[0015] FIG. 1 is a perspective view of a whole electric compressor
according to a first embodiment of the present invention, and FIG.
2 is a longitudinal section view of the electric compressor.
[0016] In an electric compressor 10 according to this embodiment,
as shown in FIGS. 1 and 2, a rear case 12, a middle case 13, and a
front case 14, which are separated in the axial direction (in the
horizontal direction of FIG. 2), are joined to each other to
constitute a housing 11. As shown in FIG. 2, the middle case 13
accommodates a compression mechanism 20; the rear case 12
accommodates an electric motor 30; and the front case 14
accommodates a motor drive circuit 40 controlling energization of
the electric motor 30.
[0017] As shown in FIG. 1, refrigerant introduced into the housing
11 through an introduction port 15 formed in the middle case 13 is
compressed by the compression mechanism 20 and is then discharged
through a discharge port 16 formed in the rear case 12.
[0018] The compression mechanism 20 is configured as a rotary type
with vanes. The compression mechanism 20 schematically includes a
cylinder block 22, a compressor rotor 23, a plurality of vanes 24,
and inlet and outlet side blocks 25 and 26. The cylinder block 22
includes a cylinder chamber 21 formed in a non-circular shape with
a smooth inner circumference as shown in FIG. 2. The compressor
rotor 23 is rotatably accommodated in the cylinder chamber 21. The
vanes 24 are provided on the outer circumference of the compressor
rotor 23 so as to be freely retracted and extended and are arranged
circumferentially at predetermined intervals. The tips of the vanes
24 slide on the inner circumferential surface of the cylinder
chamber 21. The inlet and outlet side blocks 25 and 26 are arranged
on the both sides of the cylinder block 22 in the axial direction
and close both axial ends of the cylinder chamber 21. The
compressor rotor 23 slides on the inlet and outlet side blocks 25
and 26.
[0019] In the inlet side block 25 on the left side of FIG. 2, an
inlet port (not shown) is formed so that the refrigerant introduced
from the introduction port 15 is introduced into the cylinder
chamber 21 through the inlet port. In outer peripheral part of the
cylinder block 22 or the right outlet side block 26, an outlet port
(not shown) is formed, through which the compressed refrigerant in
the cylinder chamber 21 is discharged.
[0020] Accordingly, in the compression mechanism 20, the compressor
rotor 23 is rotated with a drive shaft 31 of the electric motor 30
to change the circumferential volume of the cylinder chamber 21
while retracting and advancing the vanes 24. The refrigerant at low
pressure which is sucked into the cylinder 21 through the inlet
port is compressed, and the compressed refrigerant at high pressure
is discharged through the outlet port.
[0021] The refrigerant at high pressure discharged from the outlet
port passes through a channel between the inner circumference of
the middle case 13 and the compression mechanism 20 and then passes
through the rear case 12 accommodating the electric motor 30 to be
discharged from the discharge port 16. At this time, the
refrigerant passing through the rear case 12 cools part of the
electric motor 30 generating heat.
[0022] The electric motor 30 includes a cylindrical stator 32
pressed into and fixed to the inner circumference of the rear case
12 and a rotor 33 rotatably accommodated in the stator 32. A
plurality of coil portions provided on the stator 32
circumferentially at constant intervals are energized to excite the
stator 32, thus rotating the rotor 33.
[0023] In the center of the rotor 33, the drive shaft 31 is
inserted and engaged so as not to move relative to the rotor 33 in
a rotating direction. An end (the left end in the drawing) of the
drive shaft 31 is coupled with an end (the right end in the
drawing) of the compressor rotor 23 of the compression mechanism 20
with a non-circular fitting portion 31S. The rotation of the drive
shaft 31 is thus transmitted to the compressor rotor 23.
[0024] In the middle case 13 side of the front case 14, as shown in
FIG. 2, a partition wall 14W is provided. The other end of the
front case 14 is opened. The open end is closed by an end plate 14E
after the motor drive circuit 40 is accommodated in the front case
14 from the open side.
[0025] The motor drive circuit 40 is provided with a substrate 41.
On the substrate 41, an inverter including electronic parts such as
a switching device switching on and off of a circuit (for example,
a MOS-FET, an IGBT, or the like) is mounted.
[0026] The motor drive circuit 40 and the coil portions provided
for the stator 32 of the electric motor 30 are electrically
connected through a harness 44. In the middle of the harness 44, a
hermetic terminal 45 is provided. The connection terminal 45 is
located within an upper space portion 11U formed by projecting
upper part of the middle and front cases 13 and 14.
[0027] On the outside of the housing 11, mounting brackets 17 are
partially protruded, with which the electric compressor 10 is
mounted in an engine room, for example, on a cylinder block of the
engine or the like.
[0028] The mounting brackets 17 are protruded at total three places
on the upper and lower outside of the middle case 13 (see FIGS. 1
and 2) and an end of the rear case 12 (see FIG. 2). Each of the
mounting brackets 17 is integrally protruded on the outer
circumference of the middle or rear case 13 or 12 in a rib shape.
In each mounting bracket 17, a mounting hole 17a is formed, through
which a mounting bolt (not shown) is inserted so as to penetrate
perpendicular to the axial direction of the housing 11.
[0029] In this embodiment, a lubricating oil reservoir 50 provided
at the bottom of the housing 11 is placed under the compression
mechanism 20 in the vicinity of the mounting bracket 17 (the
mounting bracket 17 provided at the lower outside of the middle
case 13).
[0030] As shown in FIG. 2, at the bottom of the front case 14, a
lower space portion 11L for accommodating an electronic part 43 of
the motor drive circuit 40 is projected so as to have a width W2
slightly smaller than a horizontal width W1 of the attachment
bracket 17. The lubricating oil reservoir 50 is formed between the
lower space portion 11L and the mounting bracket 17 so that bottom
part of the middle case 13 is projected to have a width W1 equal to
the mounting bracket 17.
[0031] At the bottom of the lubricating oil reservoir 50, an
opening 51 is formed which is air-tightly closed detachably with a
plug 52.
[0032] On the other hand, in the compression mechanism 20, a
rotation shaft 27 of the compressor rotor 23 is rotatably supported
through sliding bearings 28F and 28R which are respectively formed
in the side blocks 25 and 26 on both sides thereof in the axial
direction. An oil path 29 (a lubricating oil feeding path) allowing
the sliding bearing 28R (in the right side in the drawing) and the
bottom of the lubricating oil reservoir 50 to communicate with each
other is formed. The lubricating oil within the lubricating oil
reservoir 50 is sucked into the sliding bearing 28R along with
rotation of the compressor rotor 23.
[0033] According to the electric compressor 10 of this embodiment,
the lubricating oil reservoir 50 provided at the bottom of the
housing 11 is placed under the compression mechanism 20.
Accordingly, the lubricating oil reservoir 50 can be provided by
effectively using dead space within the housing 11 formed under the
compression mechanism 20. The lubricating oil reservoir 50 can be
thus provided without extending the housing 11 in the axial
direction. It is therefore possible to prevent the housing 11 from
being elongated in the axial direction and prevent the electric
compressor 10 from increasing in size.
[0034] Moreover, the lubricating oil reservoir 50 is placed in the
vicinity of the mounting bracket 17 protruded on the lower outside
of the housing 11. Accordingly, the rigidity of the existing
mounting bracket 17 can secure the strength of the lubricating oil
reservoir 50. It is therefore possible to prevent the electric
compressor 10 from increasing in weight.
Second Embodiment
[0035] FIG. 3 is a longitudinal section view of an electric
compressor according to the second embodiment of the present
invention; FIG. 4 is a cross-section view along a line IV-IV of
FIG. 3; and FIG. 5 is a rear view of the electric compressor
according to this embodiment. An electric compressor 10A according
to this embodiment includes the same constituent elements as those
of the electric compressor 10 according to the first embodiment.
Hereinafter, the same constituent elements are given the same
reference numerals, and the redundant description is omitted.
[0036] The electric compressor 10A according to this embodiment
differs from the first embodiment (see FIG. 2) in that two mounting
brackets 17 and 17 are provided on the lower outside of the housing
11 so as to be separated from each other in the axial
direction.
[0037] More specifically, one of the mounting brackets 17 and 17 is
protruded on the lower outside of the rear case 12, and the other
mounting bracket 17 is protruded on the lower outside of the middle
case 13.
[0038] In this embodiment, a lubricating oil reservoir 50A is
provided across the rear and middle cases 12 and 13 between the two
mounting brackets 17 and 17.
[0039] In this embodiment, the lubricating oil reservoir 50A is
provided under the electric motor 30.
[0040] The lubricating oil reservoir 50A communicates through a
pressure introduction path 61 with a discharge port 16A opened in
the upper part of the rear end of the rear case 12. This pressure
introduction path 61 penetrates through inside of the outer wall of
the rear case 12.
[0041] More specifically, the pressure introduction path 61
includes a vertical path 61a extending downward from the discharge
port 16A opened in the upper part of the rear end of the rear case
12 and a horizontal path 61b extending from the bottom end of the
vertical path 61a in the axial direction and communicating with the
lubricating oil reservoir 50A.
[0042] As shown in FIG. 3, a lubricating oil introduction path 63
extended downward and opened to the outside of the housing 11 is
branched from the middle of the pressure introduction path 61. The
opening of the lubricating oil introduction path 63 is plugged with
a cap 64.
[0043] An oil path 62 (lubricating oil feeding path) which allows
the front end (the left end in FIG. 3) of the lubricating oil
reservoir 50A and a sliding portion (a bearing hole) of the
compression mechanism 20 to communicate with each other penetrates
through inside of the middle case 13 and side block 26 in this
embodiment.
[0044] According to the electric compressor 10A of this embodiment,
the lubricating oil reservoir 50A is provided between the mounting
brackets 17 and 17 protruded on the lower outside of the housing
11, thus achieving an efficient use of dead space. Accordingly, the
lubricating oil reservoir 50A can be provided without extending the
housing 11 in the axial direction. It is therefore possible to
prevent the housing 11 from being elongated in the axial direction
and prevent the electric compressor 10A from increasing in
size.
[0045] Moreover, the pressure of the discharge port 16A acts on oil
within the lubricating oil reservoir 50A through the pressure
introduction path 61, which feeds the lubricating oil to the
sliding portion of the compression mechanism 20. Accordingly, it is
unnecessary to provide a pump for feeding lubricating oil, thus
reducing the number of components.
[0046] The pressure introduction path 61 allows the discharge port
16A and lubricating oil reservoir 50A to communicate with each
other not through internal space of the rear case 12. Accordingly,
the pressure introduction path 61 can be used as an oil filling
path. When filling oil into the lubricating oil reservoir 50A
through the discharge port 16A, oil does not adhere to any
component arranged in the internal space of the rear case 12 (the
electric motor 30 in this example), whereby the oil can be filled
in the lubricating oil reservoir 50A more reliably.
[0047] In this embodiment, the pressure introduction path 61
allowing the discharge port 16A and lubricating oil reservoir 50A
to communicate with each other is formed to be downwardly inclined.
Accordingly, the oil separated from the refrigerant at the
discharge port 16A is naturally fed by gravity to the lubricating
oil reservoir 50A through the pressure introduction path 61. It is
more effective that the discharge port 16 is provided with an oil
separator.
[0048] In FIG. 3, the harness 44 from the connection terminal 45 is
partially shown, and some of the constituent parts within the front
case are omitted.
[0049] Hereinabove, the description is given of the preferred
embodiments of the present invention. However, the present
invention is not limited to the aforementioned embodiments and can
be variously modified. For example, the present invention is not
limited to the electric compressor used for a refrigeration cycle
of the air conditioner, and the fluid treated in the electric
compressor is not limited to the refrigerant. Moreover, the
compressor may be an eccentric roller type rotary compressor or may
be other than the rotary compressors.
INDUSTRIAL APPLICABILITY
[0050] The present invention is available for electric
compressors.
* * * * *