JP2001263229A - Motor-driven compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor-driven compressor capable of reducing size and weight and easily securing an arranging space when used for an air conditioner of a passenger car. SOLUTION: A housing chamber 6 is constituted of an area surrounded by a cylinder block 2 and a front housing 3, and a compression mechanism 7 and an electric motor 8 for driving the compression mechanism 7 are arranged in the housing chamber 6. A rotor 14 of the electric motor 8 is constituted by laminating a large number of silicon steel plates 15, and both ends are provided with end plates 16 for fixing the silicon steel plates 15 to a driving shaft 9. A lug plate 17 integrally rotatably fixed to the driving shaft 9 is integrally formed with one end plate 16. A swash plate 18 is supported by the driving shaft 9 so as to be slidable and tiltable in the axial direction, and can slide and tilt to the driving shaft 9 via the lug plate 17 and a hinge mechanism 19, and can integrally rotate with the driving shaft 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric compressor used for a vehicle air conditioner, for example.

[0002]

2. Description of the Related Art Conventionally, a compressor used in an air conditioner for a vehicle generally uses an engine as a drive source.
However, in recent years, an electric vehicle driven by a battery instead of an engine has been put into practical use. In this case, the compressor is driven by a motor.

[0003] An electric compressor is known as a compressor incorporated in a refrigerant circuit of a heat exchange device such as a vehicle air conditioner. Conventionally, an electric compressor is disclosed in, for example, Japanese Patent Application Laid-Open No. 5-187.
As in the compressor disclosed in Japanese Patent Publication No. 356, an electric motor and a refrigerant compression mechanism driven by the motor are housed in a case. The refrigerant compression mechanism includes a piston housed in a reciprocating manner in a cylinder bore in the compressor, and a swash plate provided in a swash plate chamber defined in the compressor to convert the rotational motion of the motor into a reciprocating motion of the piston. Is done.

[0004]

In the conventional electric compressor, the housing for the electric motor and the housing for the compression mechanism are separated by a wall, and the output shaft of the electric motor also serves as the drive shaft of the compression mechanism. For this purpose, it extends through the partition wall to the accommodation room of the compression mechanism. Therefore, the compression mechanism and the electric motor are arranged at a considerable distance in the axial direction of the drive shaft, and the entire compressor is large. For vehicles, especially passenger cars,
It is desirable that the space required for disposing the compressor be as small as possible.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to reduce the length and reduce the size and weight of the apparatus, and to provide an arrangement for use in an air conditioner of a passenger car or the like. An object of the present invention is to provide an electric compressor in which space can be easily secured.

[0006]

According to one aspect of the present invention, there is provided an electric compressor having an electric motor and a compression mechanism in a housing. The shaft and the drive shaft of the compression mechanism are formed by a single shaft, and the chamber for the electric motor and the chamber for the compression mechanism are united without providing a partition wall between the two chambers. Therefore, according to the present invention, the electric motor and the compression mechanism can be arranged in the accommodation room of the housing as close to each other as possible, and the electric compressor can be reduced in size and weight.

According to a second aspect of the present invention, in the first aspect of the invention, the rotor of the electric motor includes a laminated iron core, and a rotating portion of the compression mechanism is used to fix the laminated plate to the shaft. ing. Therefore, according to the present invention, the rotating part of the compression mechanism is arranged close to the rotor of the electric motor, and a part of the rotating part functions to prevent the laminated plate constituting the rotor from moving with respect to the shaft. As a result, the number of parts for fixing the rotor can be reduced.

According to a third aspect of the present invention, in the second aspect of the present invention, the rotor has one rotor end integrally formed with the rotating portion. Therefore, in the present invention, the number of parts is further reduced.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the compression mechanism is configured to be integrally rotatable with the shaft by a connection guide mechanism as the compression mechanism. A cam plate that is operatively connected to the shaft so as to be tiltable with sliding movement in the axial direction and converts the rotation of the shaft into reciprocating motion of a piston, and controls a pressure in a chamber in which the cam plate is housed. A variable displacement compression mechanism for controlling the tilt angle of the cam plate to change the stroke amount of the piston.

Therefore, in the present invention, even if the rotation speed of the shaft driven by the electric motor is constant, the stroke amount of the piston is changed according to the inclination angle of the cam plate, and the discharge capacity is changed. Further, by changing the rotation speed of the shaft by the electric motor, the amount of movement of the piston per unit time, that is, the discharge amount is changed, and the discharge capacity can be changed over a wide range together with the operation of the variable displacement compression mechanism.

According to a fifth aspect of the present invention, in the first aspect of the present invention, a swash plate supported at a constant inclination angle with respect to the shaft is used as the compression mechanism. A fixed displacement swash plate type compression mechanism for converting the rotation of the shaft into a reciprocating motion of a fixed stroke of a piston housed reciprocally in a cylinder bore via the shaft.

Therefore, in the present invention, the stroke amount of the piston is kept constant, and the displacement per unit time is changed by changing the rotation speed of the shaft.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention embodied in a variable displacement electric compressor will be described below with reference to FIG.

As shown in FIG. 1, a compressor 1 includes a cylinder block 2, a front housing 3 joined to a front end thereof, and a rear joint joined to a rear end of the cylinder block 2 via a valve forming body 4. And a housing 5. The housings 3, 5 and the cylinder block 2 are joined and fixed to each other by a plurality of through bolts (not shown).

An accommodation chamber 6 is defined by a region surrounded by the cylinder block 2 and the front housing 3.
A compression mechanism 7 and an electric motor (hereinafter, simply referred to as a motor) 8 for driving the compression mechanism 7 are provided in the accommodation chamber 6. A drive shaft 9 in which an output shaft of a motor 8 and a drive shaft of a compression mechanism are integrated is rotatably supported between the front housing 3 and the cylinder block 2 via a radial bearing 10. The drive shaft 9 has a front end abutting on the thrust bearing 11 and a rear end urged forward by a spring 12 disposed in a housing recess formed in the center of the cylinder block 2.

The electric motor 8 has a stator 13 fixed to the front housing 3 and a rotor 14 fixed on the drive shaft 9 so as to be integrally rotatable. Rotor 1
Numeral 4 is provided with a laminated iron core on which a large number of silicon steel plates 15 as laminated plates are laminated. In order to prevent the silicon steel plate 15 from moving in the axial direction of the drive shaft 9, end plates (at both ends of the laminated iron core) are provided. A rotor end 16 is provided. The end plate 16 is formed of a non-magnetic material such as aluminum, stainless steel, and brass.

The drive shaft 9 has a rotary support (lug plate) 17, a swash plate 18 as a cam plate, and a hinge mechanism 19 as a connection guide mechanism interposed between the lag plate 17 and the swash plate 18. Is provided. The lug plate 17 is formed integrally with one end plate 16. That is, the rotor 14 has one rotor end integrally formed with the rotating part of the compression mechanism. The other end plate 16 is fixed to the drive shaft 9 by a retaining ring (not shown).

The swash plate 18 is supported on the drive shaft 9 so as to be slidable and tiltable in the axial direction. The swash plate 18 can slide and tilt with respect to the drive shaft 9 and can rotate integrally with the drive shaft 9 by the lug plate 17 and the hinge mechanism 19.

The cylinder block 2 is formed with a plurality of cylinder bores 2a (only one is shown) so as to surround the drive shaft 9 at equal angular intervals. Each cylinder bore 2a extends parallel to the drive shaft 9, and each cylinder bore 2a
A single-headed piston 20 is reciprocally housed in a. The front end of each piston 20 is moored to the outer periphery of the swash plate 18 via a pair of shoes 21. In each cylinder bore 2a, a compression chamber 22 whose volume changes according to the reciprocating motion of the piston 20 is defined between the piston end face and the valve body 4.

In the rear housing 5, a suction chamber 23 and a substantially annular discharge chamber 24 surrounding the suction chamber 23 are formed separately. A suction port 25 and a discharge port 26 are formed in the valve forming body 4 for each compression chamber 22, and a suction valve 25 a and a discharge valve 26 a are formed corresponding to these ports 25 and 26.

In the cylinder block 2, the valve body 4, and the rear housing 5, an air supply passage 27 that communicates the storage chamber 6 with the discharge chamber 24, a communication between the storage chamber 6 and the suction chamber 23, and an orifice in the middle. And a bleed passage 28 provided. A control valve 29 is provided in the middle of the air supply passage 27. This control valve 29 is disclosed in, for example, Japanese Patent Application Laid-Open No. 6-12328.
A diaphragm configured to be similar to the control valve disclosed in Japanese Patent Publication No. 1 and detecting the suction pressure to be displaced, and a valve mechanism (neither shown) for controlling the opening degree of the air supply passage 27 by the displacement of the diaphragm. It has.

In the control valve 29, when the pressure in the suction chamber 23 becomes lower than a predetermined pressure, the air supply passage 27 is opened, and when the pressure is higher than the predetermined pressure, the air supply passage 27 is kept closed. Compressor 1
Is variably adjusted by controlling the pressure in the storage chamber 6 by the control valve 29.

Next, the operation of the compressor configured as described above will be described. With the rotation of the drive shaft 9 by the electric motor 8, the swash plate 18 rotates together with the drive shaft 9, and the rotational motion of the swash plate 18 is converted to the reciprocating motion of each piston 20 via the shoe 21. With the continuation of the driving, the suction, compression, and discharge of the refrigerant are sequentially repeated in the compression chamber 22. The refrigerant supplied from the external refrigerant circuit to the suction chamber 23 is sucked into the compression chamber 22 through the suction port 25, is compressed by the movement of the piston 20, and is discharged to the discharge chamber 24 through the discharge port 26. Is done. The refrigerant discharged into the discharge chamber 24 is sent out from the discharge holes to the external refrigerant circuit.

When the pressure in the suction chamber 23 is small, the opening degree of the control valve 29 is increased, and the accommodation chamber pressure Pc is induced to be higher, so that the inclination angle of the swash plate 18 (the plane perpendicular to the drive shaft 9 and the swash plate 18 Angle between the piston 20 and each piston 20
And the discharge capacity decreases. Further, when the pressure in the suction chamber 23 is large, the valve opening is reduced and the accommodation chamber pressure Pc is induced to be lower, the inclination angle of the swash plate 18 is increased, the stroke of each piston 20 is increased, and the discharge capacity is increased. I do.

While the drive shaft 9 is rotating, the rotor 14 receives a thrust force from the lug plate 17 due to the compression reaction force of the piston. Since the movement of the end plate 16 on the front housing 3 side with respect to the drive shaft 9 is restricted by the retaining ring, even when the drive shaft 9 is rotated at a high speed, the silicon steel plate 15 is held between the end plate 16 and the lug plate 17. In this state, it is fixedly held at a predetermined position.

This embodiment has the following effects. (1) Since the electric motor 8 and the compression mechanism 7 are accommodated in one accommodation room 6 having no partition wall between them, the electric motor 8 and the compression mechanism 7 can be arranged as close as possible. The compressor 1 can be reduced in size, and also can be reduced in weight.

(2) Since the lug plate 17 is used for fixing the silicon steel plate 15 constituting the laminated iron core of the rotor 14 to the drive shaft 9, the axial length of the compressor 1 as a whole is shorter. it can.

(3) Since one rotor end 16 of the rotor 14 is formed integrally with the lug plate 17,
The number of parts is reduced, and the assembling work is facilitated. (4) Since the compression mechanism 7 is of a variable capacity type, the refrigerant gas per unit time can be wide-ranging over a wide range by a combination of the rotation speed control of the drive shaft 9 by the electric motor 8 and the capacity changing operation of the compression mechanism 7. Can be arbitrarily controlled, and the discharge capacity can be changed efficiently.

(Second Embodiment) Next, a second embodiment will be described with reference to FIG. This embodiment is characterized in that a fixed displacement swash plate type compression mechanism for converting the rotation of the shaft into a reciprocating motion of a fixed stroke of the piston is provided through a swash plate supported at a constant inclination angle with respect to the shaft. It is very different from the form. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

One end plate of the rotor 14 has a cam member 30 fixed to the drive shaft 9 so as to be integrally rotatable.
And are integrally formed. The cam member 30 has a support surface 30a.
And a spindle 30b. The support surface 30a intersects the axis of the drive shaft 9 at a predetermined angle, and a support shaft portion 30b is formed perpendicular to the support surface 30a.
A ring-shaped swash plate 33 is rotatably supported on the cam member 30 in a state where a thrust bearing 31 is interposed between the cam member 30 and the support surface 30a, and a radial bearing 32 is interposed between the cam member 30 and the support shaft portion 30b. I have. In this embodiment, the discharge chamber 24 is disposed inside, and the suction chamber 23 is formed in a substantially annular shape so as to surround the discharge chamber 24.

In this compressor, the cam member 30 rotates integrally with the drive shaft 9 with the rotation of the drive shaft 9 by the electric motor 8. When the swash plate 33 that contacts the support surface 30a via the thrust bearing 31 swings, the rotational movement of the cam member 30 causes a constant stroke corresponding to the inclination angle of the support surface 30a with respect to the axis of the drive shaft 9. Is converted into a reciprocating linear motion of the piston 20 at With the continuation of the driving, the suction, compression, and discharge of the refrigerant are sequentially repeated in the compression chamber 22.

Therefore, this embodiment has the following effect in addition to the effect (1) of the above embodiment. (5) Since the cam member 30 is used for fixing the silicon steel plate 15 to the drive shaft 9, the axial length of the compressor 1 as a whole can be reduced.

(6) Since one rotor end 16 of the rotor 14 is formed integrally with the cam member 30, the number of parts is reduced, and the assembling work is facilitated. (7) The configuration of the compression mechanism 7 is simplified as compared with the case of the variable capacity type.

(8) Since the swash plate 33 reciprocates the piston 20 only by swinging without rotating integrally with the drive shaft 9, the swash plate 33 and the shoe 21 are inclined more than the swash plate 33 rotates integrally with the drive shaft 9. The frictional resistance with the plate is reduced, and noise and vibration are also reduced.

(9) Since the swash plate 33 is rotatably supported by the cam member 30 via a rolling bearing, frictional resistance between the cam member 30 and the swash plate 33 is reduced, and mechanical loss is reduced. Reduced.

The embodiment is not limited to the above, and may be configured as follows, for example. Instead of integrally forming the lug plate 17 or the cam member 30 with the one end plate 16, the lug plate 17 or the cam member 30 may be fixed to the drive shaft 9 in a state of contact with the end plate 16. Also in this case, the lug plate 17 or the cam member 3
0 can be used for fixing the silicon steel plate 15. In addition, a material other than a non-magnetic material can be used for the lug plate 17 or the cam member 30.

The lug plate 17 or the cam member 3
A thrust bearing may be interposed between the front plate 3 and the end plate 16 disposed on the opposite side of the thrust bearing. In this case, the lug plate 1 is
The front housing 3 can bear a compression reaction force acting on the cam member 7 or the cam member 30 in a wide area. The durability of the thrust bearing is improved and the rotation of the drive shaft 9 is performed smoothly as compared with a configuration in which the compression reaction force is supported by a small thrust bearing that supports the drive shaft 9.

The diameter of the front housing 3 is made larger than the diameter of the cylinder block 2, and the coil end is positioned at the front end of the piston moving range so as to avoid interference between the coil end of the stator 13 and the piston 20. The stator 13 may be arranged so as to overlap on the outer peripheral side. In this case, the overall length of the compressor can be further reduced.

A wobble-type compression mechanism in which the swash plate does not rotate integrally with the drive shaft 9 but swings with the rotation of the drive shaft 9 may be employed as the variable capacity compression mechanism.

The cam member 30 may be formed integrally with the drive shaft 9. The swash plate may be configured to rotate integrally with the drive shaft 9 by a swash plate compressor in which the stroke of the piston 20 is constant.

The rotation of the drive shaft 9 is controlled by the rotation of the swash plate 18, the swing of the swash plate 33, and the piston 2 through the shoe 21.
The present invention is not limited to a compressor having a compression mechanism that converts the motion into a reciprocating linear motion of 0, but may be applied to a vane compressor or the like.

As the control valve 29, a so-called external control valve whose opening can be adjusted by an external electric signal may be used. ○ The compressor is not limited to a single-stage type, but a low-pressure compression chamber that draws in and compresses refrigerant gas from an external refrigerant circuit, and a high-pressure compressor that draws in and compresses intermediate-pressure refrigerant gas that has been compressed at least once. And a multi-stage compressor having a compression chamber.

The compressor is not limited to a vehicle air conditioner, but may be applied to a compressor used in another refrigerant circuit. ○ Not limited to the compressor using the single-headed piston 20,
The present invention may be applied to a compressor using a double-headed piston.

The refrigerant of the compressor 1 is not limited to Freon,
Other refrigerants such as O ₂ (carbon dioxide) may be used. The electric motor 8 is not limited to a type in which the rotor 14 is surrounded by the stator 13, that is, a type in which the rotor 14 and the stator 13 face each other in the radial direction of the drive shaft 9 of the electric motor 8. (Axial type) arranged so as to face the surface. In this case, the axial length of the electric motor is
As a result, the axial length of the electric compressor can be further reduced.

Next, technical ideas other than those described in the claims, which can be understood from the above embodiment, will be described below together with their effects. (1) In the invention according to claim 5, a support surface intersecting the shaft at a predetermined angle with an axis of the shaft,
A support shaft formed perpendicular to the support surface, and the swash plate is positioned relative to the support shaft via a rolling bearing with a thrust bearing interposed between the support surface and the swash plate. It is rotatably supported. In this case, the frictional resistance between the support shaft and the support surface and the swash plate is reduced, and the mechanical loss is reduced even when the compression ratio is high.

(2) The thrust bearing according to any one of claims 4, 5 and (1), wherein the thrust bearing is provided between the housing and a surface of the rotor opposite to the surface facing the rotating portion. Is interposed. In this case, the housing can bear the compression reaction force of the piston over a wide area, and the durability of the thrust bearing is improved compared to a configuration in which the compression reaction force is supported by a small thrust bearing that supports the shaft. Is performed smoothly.

[0047]

As described in detail above, according to the first to fifth aspects of the present invention, it is possible to reduce the size and weight of the electric compressor, and to use the compressor in an air conditioner of a passenger car or the like. The arrangement space can be easily secured.

[Brief description of the drawings]

FIG. 1 is a sectional view of a compressor according to a first embodiment.

FIG. 2 is a sectional view of a compressor according to a second embodiment.

[Explanation of symbols]

2 ... Cylinder block that constitutes a housing, 3 ... Front housing, 5 ... Rear housing, 2
a ... Cylinder bore, 6 ... Accommodation chamber, 7 ... Compression mechanism, 8 ... Electric motor, 9 ... Drive shaft shaft, 14 ... Rotor, 15 ...
Silicon steel plate as laminate, 16 ... end plate, 1
7 ... Lug plate as rotating part, 18 ... Swash plate as cam plate, 20 ... Piston, 30 ... Cam member as rotating part, 33 ... Swash plate.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H076 AA06 BB38 CC07 CC20 CC46 CC47 CC83 5H607 AA12 BB01 BB14 CC03 DD03 DD16 EE50 FF07 GG01 GG02 GG08

Claims (5)

[Claims] 1. An electric compressor comprising an electric motor and a compression mechanism in a housing, wherein an output shaft of the electric motor and a drive shaft of the compression mechanism are formed by a single shaft. An electric compressor in which a chamber for accommodating a motor and a chamber for accommodating the compression mechanism are united without providing a partition wall between both chambers. 2. The electric compressor according to claim 1, wherein the rotor of the electric motor includes a laminated iron core, and a rotating part of the compression mechanism is used to fix the laminated plate to the shaft. 3. The electric compressor according to claim 2, wherein one end of the rotor for fixing the laminated plate is integrally formed with the rotating portion. 4. The compression mechanism is operably connected to the shaft by a connection guide mechanism so as to be integrally rotatable with the shaft and to be tiltable with respect to the shaft while being slid in the axial direction of the shaft. A cam plate for converting the reciprocating motion of the piston is provided, and a variable displacement compression mechanism for changing the stroke amount of the piston by controlling the tilt angle of the cam plate by controlling the pressure in the chamber containing the cam plate is provided. The electric compressor according to any one of claims 1 to 3. 5. A compression mechanism wherein a rotation of the shaft is reciprocated by a fixed stroke of a piston reciprocally housed in a cylinder bore via a swash plate supported at a constant inclination angle with respect to the shaft. The electric compressor according to any one of claims 1 to 3, further comprising a fixed displacement swash plate type compression mechanism that performs conversion.