Information
-
Patent Grant
-
6619933
-
Patent Number
6,619,933
-
Date Filed
Monday, August 27, 200123 years ago
-
Date Issued
Tuesday, September 16, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Walberg; Teresa
- Patel; Vinod D.
Agents
-
CPC
-
US Classifications
Field of Search
US
- 417 4101
- 417 366
- 062 505
-
International Classifications
-
-
Disclaimer
Terminal disclaimer Term Extension
179
Abstract
A motor-driven compressor is formed integrally with a compressor device for compressing refrigerant and a motor for driving the compressor device. The motor-driven compressor includes a drive circuit. The drive circuit controls the driving of the motor. The drive circuit is provided on an exterior surface wall of a refrigerant suction passages and the drive circuit is coated by or buried within an insulating resin material. In such motor-driven compressors, the drive circuit may be sufficiently cooled without using additional cooling equipment. As a result, providing additional cooling equipment with the drive circuit in the motor-driven compressors is no longer necessary.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to motor-driven compressors formed integrally with a compressor device for compressing refrigerant and a motor for driving the compressor device, and more particularly, to motor-driven compressors that are suitable for use in air conditioning systems for vehicles.
2. Description of Related Art
Motor-driven compressors are driven by power supply, for example, an external power source, such as a battery. Motor-driven compressors formed integrally with a compression portion and a motor for compressing refrigerant are known in the art. In such known compressors, a drive circuit for controlling the driving of the motor is separated from the compression portion and the motor, and an inverter is supplied to the motor for converting power supplied from a power source into a suitable current for the motor. Such an inverter generally comprises a plurality of switching elements. The switching elements may generate a significant amount of heat caused by, for example, electrical loss in the switching elements. Therefore, an air-cooled or a water-cooled type inverter has been used in such known motor driven compressors. In the air-cooled type inverter, a radiator or a fan is employed. In the water-cooled type inverter, a water cooling radiator and water circulating pipes are employed. Such additional equipment increases cost of manufacturing the automotive air-conditioning system.
SUMMARY OF THE INVENTION
A need has arisen to provide motor-driven compressors with drive circuits that do not require additional cooling equipment, such as radiators and fans.
In an embodiment of this invention, a motor-driven compressor is formed integrally with a compressor device for compressing refrigerant and a motor for driving the compressor device. The motor-driven compressor comprises a drive circuit. The drive circuit controls the driving of the motor. The drive circuit is provided on an exterior surface wall of a refrigerant suction passage, and the drive circuit is coated by or buried within an insulating resin material.
Objects, features, and advantages of embodiments of this invention will be apparent to persons of ordinary skill in the art from the following detailed description of the invention and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be more readily understood with reference to the following drawings.
FIG. 1
is a longitudinal, cross-sectional view of a motor-driven compressor, according to an embodiment of the present invention.
FIG. 2
is a longitudinal, cross-sectional view of a motor-driven compressor, according to another embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to
FIG. 1
, a motor-driven compressor according to an embodiment of the present invention is shown. A motor-driven compressor
10
has a discharge housing
51
, an intermediate housing
52
, and a suction housing
1
. These housings
51
,
52
, and
1
are made from a metal material including aluminum. Discharge housing
51
and intermediate housing
52
are connected by a plurality of bolts
53
a.
Intermediate housing
52
and suction housing
1
are connected by a plurality of bolts
53
b.
Discharge housing
51
has a discharge port
67
at its axial end portion. A fixed scroll member
60
and an orbital scroll member
70
are provided in discharge housing
51
, so that both scroll members
60
and
70
form a refrigerant compression area
75
.
Fixed scroll member
60
includes an end plate
61
, a spiral element
62
provided on one surface of end plate
61
, and a securing portion
63
formed on the other surface of end plate
61
. Securing portion
63
is fixed to an inner surface of the side wall of discharge housing
51
by a plurality of bolts
64
. A discharge hole
65
is formed through a center of end plate
61
. Orbital scroll member
70
has an end plate
71
, a spiral element
72
provided on one surface of end plate
70
, and a cylindrical boss portion
73
projecting from the other surface of end plate
71
. A rotation prevention mechanism
68
comprises a plurality of balls, each of which travels in a pair of rolling ball grooves formed in opposing ring-shaped races and is provided between the surface of end plate
71
and the axial end surface of intermediate housing
52
. Rotation prevention mechanism
68
prevents the rotation of orbital scroll member
70
, but allows an orbital motion of scroll member
70
at a predetermined orbital radius with respect to the center of fixed scroll member
60
. A suction chamber
69
is formed outside of scroll members
60
and
70
. Compression area
75
is defined between fixed scroll member
60
and orbiting scroll member
70
. Alternatively, an Oldham coupling may be used as the rotation prevention mechanism.
A drive shaft
55
is disposed in intermediate housing
52
and suction housing
1
. Drive shaft
55
has a smaller diameter portion
55
a
at one end portion and a larger diameter portion
55
e
at the other end portion. Suction housing
1
has a partition wall
1
b
extending axially at its middle portion. Partition wall
1
b
extends across the width of suction housing
1
. A cylindrical projecting portion
1
a
is provided on one surface of partition wall
1
b
to extend toward the side of compression area
75
. Smaller diameter portion
55
a
is rotatably supported by projection portion
1
a
via a bearing
56
. Larger diameter portion
55
e
is rotatably supported by intermediate housing
52
via a bearing
57
. An eccentric pin
55
c
projects from an end surface of larger diameter portion
55
e
in a direction along the axis of drive shaft
55
. Eccentric pin
55
c
is inserted into an eccentric bushing
58
, which is rotatably supported by boss portion
73
of orbital scroll member
70
via a bearing
59
.
A motor
80
, such as a three-phase direct current motor, is disposed in intermediate housing
52
and suction housing
1
. Motor
80
has a stator
81
, a coil
82
, and a rotor
83
. Stator
81
is fixed on the inner surface of intermediate housing
52
and suction housing
1
. Coil
82
is provided around stator
81
. Rotor
83
is fixed on drive shaft
55
.
A plurality of sealed terminals
84
are provided on the upper or left portion of partition wall
1
b
in suction housing
1
. The right side and the left side of partition wall
1
b,
as depicted in
FIG. 1
, are separated from each other by partition wall
1
b
and a terminal plate
1
c.
A refrigerant suction port
8
is provided through the outer surface of suction housing
1
at a position between intermediate housing
52
and partition wall
1
b.
The opening of suction housing
1
, which is located at an end opposite to the side of intermediate housing
52
, is closed by a lid
6
. Lid
6
is fixed to the axial end of suction housing
1
via a plurality of fasteners, such as bolts
9
. Lid
6
may be formed from the same material as used for suction housing
1
, such as aluminum or an aluminum alloy, or, alternatively, may be formed from other materials, such as iron or other magnetic materials. Lid
6
preferably is made from a material capable of shielding against electromagnetic radiation.
An enclosure
4
a
is provided on the exterior surface of partition wall
1
b
within suction housing
1
. A drive circuit
4
includes an inverter
2
and control circuit
3
. Drive circuit
4
for controlling the driving of motor
80
is located within enclosure
4
a.
Output terminals
5
of inverter
2
are attached to enclosure
4
a.
Enclosure
4
a
is fixed on the surface of partition wall
1
b.
Output terminals
5
are coupled to sealed terminals
84
via a plurality of terminal lead wires
5
a.
Sealed terminals
84
are coupled to motor
80
via a plurality of motor lead wires
84
a.
Enclosure
4
a
is filled with an insulating resin material
100
, such as an epoxy resin. A capacitor
11
is provided on the outer surface of the boundary portion between intermediate housing
52
and suction housing
1
. Capacitor
11
is attached to this outer surface via an attachment
12
and a fixing pin
12
a.
Capacitor
11
may be provided at a position near the compressor body. A connector
7
is provided on the wall of suction housing
1
on the opposite side of partition wall
1
b
i.e., on the right side of partition wall
1
b
in FIG.
1
. Connecter
7
is connected to drive circuit
4
from connector terminals
7
′ via output terminals
5
through connector lead wires
7
a.
Connector
7
is coupled to an external power source (not shown), such as a battery mounted on the vehicle, through capacitor
11
.
In motor-driven compressor
10
, when motor
80
is driven by current, such as three-phase current provided from inverter
2
, drive shaft
55
is rotated, and orbiting scroll member
70
, which is supported by cccentric pin
55
c,
is driven in an orbital motion by the rotation of drive shaft
55
. The compressor device comprises scroll members
60
and
70
. When orbiting scroll member
70
is driven in an orbital motion, compression areas
75
, which are defined between spiral element
62
of fixed scroll member
60
and spiral element
72
of orbiting scroll member
70
, move from the outer or peripheral portions of the spiral elements to the center portion of the spiral elements. Refrigerant gas, which enters into suction chamber
69
from an external fluid circuit (not shown) through suction port
8
, flows into one of compression areas
75
through an interior space of suction housing
1
, motor
80
, and an interior space of intermediate housing
52
. When compression areas
75
move from the outer portions of the spiral elements, the volume of compression areas
75
is reduced, and refrigerant gas in compression areas
75
is compressed. Compressed refrigerant gas confined within compression areas
75
moves through discharge hole
65
formed in end plate
61
. Finally, the compressed refrigerant gas is discharged into an external refrigerant circuit (not shown) through discharge port
67
.
In motor-driven compressor
10
, because drive circuit
4
is provided on the exterior surface of partition wall
1
b
in suction housing
1
, heat generated by inverter
2
of drive circuit
4
is absorbed by lower temperature refrigerant gas through partition wall
1
b.
Thus, drive circuit
4
may remain sufficiently cooled without using additional cooling equipment. Moreover, because drive circuit
4
is coated by or buried within insulating resin material
100
, if drive circuit
4
is cooled by lower temperature refrigerant gas through partition wall
1
b,
condensation at a surface of drive circuit
4
may be reduced or eliminated. Therefore, the risk of a dielectric breakdown or a malfunction of drive circuit
4
due to the formation of condensation may be reduced or eliminated, and the risk of an electrical shock may be reduced or eliminated. In addition, because drive circuit
4
is buried within enclosure
4
a
by insulating resin material
100
, if the vibration of compression area
75
or the vibration of an engine of the vehicle mounting motor-driven compressor
10
reaches drive circuit
4
, electrical components soldered on a printed-circuit board of drive circuit
4
may not be exfoliated from the printed-circuit board. Consequently, damage to electrical components on the printed-circuit board caused by the vibration may be reduced or eliminated. As a result, drive circuit
4
may not be damaged by the vibration.
Drive circuit
4
, output terminals
5
of inverter
2
, terminal lead wires
5
a,
sealed terminals
84
, connector lead wires
7
a,
and terminals
7
′ of connecter
7
are provided within a closed area surrounded by a metallic wall. Therefore, the damage of these parts due to contact with foreign objects may be reduced or eliminated. Moreover, because electromagnetic noise radiating from terminal lead wires
5
a
is blocked within the closed area surrounded by the metallic wall, malfunction of electrical parts or devices mounted on the vehicles due to electromagnetic noise may be reduced or eliminated.
Referring to
FIG. 2
, a motor-driven compressor of another embodiment of the present invention is shown. As shown in
FIG. 2
, a closed area between an interior side of lid
6
and an outer side of partition wall
1
b
is filled with an insulating resin material
100
′, such as an epoxy resin. Therefore, output terminals
5
of inverter
2
, terminal lead wires
5
a,
sealed terminals
84
, connector lead wires
7
a,
and terminals of connecter
7
are covered with insulating, resin material
100
′. As a result, the occurrence of an improper connection between terminals and lead wires, or the occurrence of dielectric breakdown due to wear between each of the lead wires that may result from the vibration of compression area
75
or the vibration of the engine of the vehicle mounting motor-driven compressor
10
may be reduced or eliminated.
As described above, in a motor-driven compressor with respect to embodiments of the present invention, because drive circuit
4
is provided on the exterior surface of partition wall
1
b
in suction housing
1
, heat generated by inverter
2
of drive circuit
4
is absorbed by lower temperature refrigerant gas through partition wall
1
b.
Therefore, in this embodiment of the present invention, providing additional cooling equipment with drive circuit
4
in the motor-driven compressor is no longer necessary. Moreover, because drive circuit
4
is covered by insulating resin material
100
, if drive circuit
4
is cooled by lower temperature refrigerant gas through partition wall
1
b,
the formation of condensation at a surface of drive circuit
4
may be reduced or eliminated. Therefore, the risk of a dielectric breakdown or a malfunction of drive circuit
4
due to the formation of condensation may be reduced or eliminated, and the risk of an electrical shock may be reduced or eliminated.
Although the present invention has been described in connection with preferred embodiments, the invention is not limited thereto. It will be understood by those skilled in the art that variations and modifications may be made within the scope and spirit of this invention, as defined by the following claims.
Claims
- 1. A motor-driven compressor formed integrally with a compressor device for compressing refrigerant and a motor for driving said compressor device, said motor-driven compressor comprising:a drive circuit for controlling the driving of said motor, said drive circuit provided on an exterior surface wall of a refrigerant suction passage, and said drive circuit coated by an insulating resin material.
- 2. The motor driven compressor of claim 1, further comprising:a plurality of connector lead wires and a plurality of connecting terminals, which connect between said drive circuit and an external circuit, wherein said connector lead wires and said connecting terminals are buried within said insulating resin material, which fills an area surrounding said connector lead wires and said connecting terminals.
- 3. The motor-driven compressor of claim 2, further comprising:a plurality of motor lead wires and a plurality of sealed terminals, which connect between said drive circuit and said motor, wherein said connector lead wires and said connecting terminals connect between said drive circuit and an external circuit, said motor lead wires and said sealed terminals connect between said drive circuit and said motor are provided within a closed space surrounded by a metallic wall.
- 4. A motor-driven compressor formed integrally with a compressor device for compressing refrigerant and a motor for driving said compressor device, said motor-driven compressor comprising:a drive circuit for controlling the driving of said motor, said drive circuit provided on an exterior surface wall of a refrigerant suction passage, and said drive circuit buried within said insulating resin material, which fill in an area surrounding said drive circuit.
- 5. The motor-driven compressor of claim 4, further comprising:a plurality of connector lead wires and a plurality of connecting terminals, which connect between said drive circuit and an external circuit, wherein said connector lead wires and said connecting terminals are buried within said insulating resin material, which fills in an area surrounding said connector lead wires and said connecting terminals.
- 6. The motor-driven compressor of claim 5, further comprising:a plurality of motor lead wires and a plurality of sealed terminals, which are connected between said drive circuit and said motor, wherein said connector lead wires and said connecting terminals connect between said drive circuit and an external circuit said motor lead wires and said sealed terminals connect between said drive circuit and said motor are provided within a closed space surrounded by a metallic wall.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2000-258289 |
Aug 2000 |
JP |
|
US Referenced Citations (15)