JP2000130362A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mitigate a thrust force applied on a thrust bearing. SOLUTION: A first and second magnets 121 and 122 are buried to generate a repulsive force in an end plate part 114b between the end plate part 114b of a turning scroll 114 and a middle housing 107. Thus, since a thrust force applied on the turning scroll 114 is received by the repulsive force between the two magnets 121 and 122, the thrust force applied on a thrust bearing part is mitigated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor, and is effective when applied to a compressor for a supercritical refrigeration cycle in which a refrigerant pressure on a high pressure side (radiator side) is higher than a critical pressure of the refrigerant.

[0002]

2. Description of the Related Art As a compressor for a refrigeration cycle, in a scroll type compressor described in Japanese Patent Application Laid-Open No. 9-310687, a thrust receiving portion (sliding member) of a front housing slidably comes in contact with an end plate portion of an orbiting scroll. In addition to receiving a thrust force at the moving surface), a discharge pressure is guided between the orbiting scroll and the front housing to reduce the thrust force acting on the thrust receiving portion (sliding surface).

[0003] Here, the thrust force refers to a force (thrust force) in a direction orthogonal to the turning direction of the orbiting scroll, of the compression reaction force acting on the orbiting scroll.

[0004]

In the supercritical refrigeration cycle, the discharge pressure is about 10 times or more higher than that of a refrigeration cycle using chlorofluorocarbon as a refrigerant (hereinafter, this refrigeration cycle is referred to as a chlorofluorocarbon cycle). The pressure difference between the pressure and the suction pressure is as large as about 5 to 8 times the CFC cycle. Therefore, if the compressor described in the above publication is directly applied to a compressor for a supercritical refrigeration cycle, the following problems may occur.

That is, like a scroll compressor,
Fixed part fixed to the housing (fixed scroll)
In a compressor that expands and contracts the volume of the working chamber by revolving a revolving part (revolving scroll) with respect to
In order to effectively implement the invention described in the above-mentioned publication, in order to effectively carry out the discharge pressure, a space (hereinafter, this space is referred to as a back pressure space) between the orbiting scroll and the front housing from which the discharge pressure is introduced, is taken from the suction side of the compressor. It is necessary to prevent a refrigerant having a discharge pressure from leaking toward the suction chamber side (hereinafter, this refrigerant is referred to as a discharge pressure refrigerant).

However, in addition to the swirling of the swirling part, in the supercritical refrigeration cycle, as described above, since the pressure difference between the discharge pressure and the suction pressure is large, the discharge pressure from the back pressure space to the suction chamber side is increased. It is difficult to seal so that the refrigerant does not leak. Therefore, if the invention described in the above publication is applied to a compressor for a supercritical refrigeration cycle as it is, the discharge pressure refrigerant leaks to the suction chamber side, and the thrust force acting on the thrust receiving portion (sliding surface) is reduced. There is a possibility that a problem may occur that the pressure cannot be sufficiently reduced and the efficiency (performance) of the compressor is reduced.

As is apparent from the above description, the above problem occurs when the differential pressure between the discharge pressure and the suction pressure is large, and therefore occurs only in the compressor for the supercritical refrigeration cycle. This is not a problem but a problem that can occur in all compressors used in a state where the differential pressure between the discharge pressure and the suction pressure is large. In view of the above, it is an object of the present invention to reduce a thrust force acting on a thrust receiving portion without lowering the efficiency of a compressor.

[0008]

The present invention uses the following technical means to achieve the above object. According to the first aspect of the present invention, of the compression reaction force acting on the turning portion (114), the thrust receiving portion (120) that receives a thrust force orthogonal to the turning direction of the turning portion (114) is connected to the turning portion (11).
4) a first magnet (121) that is disposed at a portion facing the housing (107) and exerts a magnetic force, and is disposed at a portion corresponding to the first magnet (121) in the housing (107); The thrust receiving portion (120) is configured to have the second magnet (122) that exerts a repulsive force on the first magnet (121).
As described in the above publication, the repulsive force between 2) receives a thrust force acting on the turning portion (114).
The thrust force acting on the swirling portion (114) can be received without sealing so that the discharge pressure refrigerant does not leak from the back pressure space to the suction side. Therefore, the thrust force acting on the thrust receiving portion can be reduced without lowering the efficiency of the compressor.

Further, since the thrust force acting on the turning portion (114) can be reduced (reduced), the turning portion (1) can be reduced.
The efficiency of the compressor can be improved by reducing the sliding loss (friction loss) of 14), and the turning portion (114)
Alternatively, the durability (reliability) of the compressor can be improved by suppressing wear of the housing (107). According to the second aspect of the present invention, the thrust receiving portion (120) which receives a thrust force orthogonal to the turning direction of the orbiting scroll (114) out of the compression reaction force acting on the orbiting scroll (114).
Is the housing (10) of the orbiting scroll (114).
7) a first magnet (121) which is disposed at a portion facing the first magnet and exerts a magnetic force, and a first magnet (121) which is disposed at a portion of the housing (107) corresponding to the first magnet (121). The second to apply repulsion to
It is characterized by having a magnet (122).

As a result, the thrust force acting on the thrust receiving portion can be reduced without lowering the efficiency of the compressor, as in the first aspect of the invention.
The durability (reliability) of the compressor can be improved.
Incidentally, the reference numerals in parentheses of the above means are examples showing the correspondence with specific means described in the embodiments described later.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In this embodiment, a compressor according to the present invention is applied to a supercritical refrigeration cycle.
1 is a schematic diagram of a supercritical refrigeration cycle. In FIG. 1, 100
Is a compressor that sucks a refrigerant (carbon dioxide) and compresses the sucked refrigerant to a pressure higher than the critical pressure of the refrigerant.
Is a radiator that performs heat exchange between outdoor air and a refrigerant.
A decompressor 300 decompresses the refrigerant flowing out of the radiator 200. A decompressor 400 evaporates a liquid-phase refrigerant out of the refrigerant in a gas-liquid two-phase state by the decompressor 300 to cool air blown into the room. It is an evaporator.

The pressure reducer 300 is disclosed in Japanese Patent Application No. 8-339.
Since this is the same as the pressure control valve described in the '62 application, detailed description of the pressure reducer 300 is omitted in this specification. Reference numeral 500 denotes an accumulator (gas-liquid separation unit) that separates the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant and causes the gas-phase refrigerant to flow toward the suction side of the compressor 100. This is an internal heat exchanger that exchanges heat between the refrigerant flowing out of the radiator 200 and the refrigerant flowing out of the radiator 200.

Next, the compressor 100 according to the present embodiment will be described. FIG. 2 shows an axial cross section of the compressor 100 according to the present embodiment. The compressor 100 includes a scroll-type compression mechanism Cp for sucking and compressing a refrigerant, and an electric motor (the present invention) for driving the scroll-type compression mechanism. In the embodiment,
And a DC brushless motor (Mo).

Here, an outline of the electric motor Mo will be described. 101 is a front housing (motor housing) 101 and 102 is a front housing 101
And a stator core (yoke) 102 made of a magnetic material such as a silicon steel plate. 103 is the stator core 1
02, a winding (coil) 103, and a stator coil 104 is composed of the winding 103, the stator core 102, and the like.

Reference numeral 105 denotes a rotor 105 which rotates within the stator 104. The rotor 105 includes a plurality of permanent magnets 106 and a shaft 109 rotatably supported by a front housing 101 and a middle housing 107 via bearings 108. And so on. Note that 11
Reference numeral 0 denotes terminals for supplying electric power to the stator 104 (winding 103), and these terminals 110 are connected to a motor drive circuit (not shown).

Next, the scroll type compression mechanism Cp will be described. Reference numeral 111 denotes a shell (fixed portion) which is fixed to the middle housing 107 and forms a space together with the middle housing 107. The spiral housing 111 has a spiral shape projecting toward the middle housing 111 on the middle housing 111 side. A tooth portion 112 is formed.

The middle housing 107 and the shell 1
The orbiting scroll (orbiting portion) 114 in which a spiral tooth portion 113 forming the working chamber V is formed in contact with the tooth portion 112 of the shell 111 is disposed between the rotary scroll 11 and the rotary scroll 11. 114 is a shell (fixed scroll) 1
By swirling with respect to 11, the volume of the working chamber V is enlarged or reduced, and the refrigerant (fluid) is sucked and compressed.

The orbiting scroll 114 has a boss 114a formed substantially at the center of the orbiting scroll 114 and a crank 109a formed at one end (right side in the drawing) of the shaft 109.
They are connected via a shell type (type having no inner ring) needle roller bearing (needle bearing) 115. Since the crank portion 109a is formed at a position eccentric to the radially outward side from the rotation center of the shaft 109,
When the shaft 109 rotates, the orbiting scroll 114
Rotates (rotates) around the shaft 109.

Incidentally, reference numeral 116 denotes the orbiting scroll 114.
Is slidably connected to the crank portion 109a to form a driven crank mechanism for increasing the contact surface pressure between the two tooth portions 112 and 113.
Reference numeral 16 designates a small displacement of the orbiting scroll 114 with respect to the crank portion 109a by the force in the orbiting direction of the compression reaction force acting on the orbiting scroll 114, and
13 is increased.

Incidentally, reference numeral 120 denotes the orbiting scroll 11.
4 of the compression reaction force acting in the direction orthogonal to the turning direction of the orbiting scroll 114 (the direction parallel to the longitudinal direction of the shaft 109) (hereinafter, this force is referred to as thrust force).
And a thrust receiving portion (thrust bearing) for supporting the orbiting scroll 114 so as to be able to turn.

The thrust receiving portion 120 is formed in the middle housing 1 of the end plate portion 114b of the orbiting scroll 114.
A plurality of permanent magnets embedded and fixed at a portion facing 07 (hereinafter, this permanent magnet is referred to as a first magnet) 12
1 and a plurality of permanent magnets buried and fixed in a portion of the middle housing 107 corresponding to the first magnet 121 to apply a repulsive force to the first magnet 121 (hereinafter, this permanent magnet is referred to as a second magnet). ) 122.

The first magnet 121 is disposed circumferentially around the crank portion 109a as shown in FIG. 3, and the second magnet 122 is disposed around the axis of the shaft 109 as shown in FIG. Are arranged circumferentially. Also, even if the orbiting scroll 114 is turned, the first magnet 121 surely faces the second magnet 122.
The diameter of the first magnet 121 is the same as that of the second magnet 12.
2 is smaller than the diameter.

In FIG. 2, reference numeral 132 denotes a rotation preventing pin for preventing the orbiting scroll 114 from rotating (rotating) around the crank portion 109a when the orbiting scroll 114 turns. Pin 132
Are slidably in contact with the inner walls of four ring portions 114c (see FIG. 3) formed radially outward of the orbiting scroll 114. Therefore, when the shaft 109 rotates, the orbiting scroll 114 orbits (revolves) around the rotation center of the shaft 109 without rotating (rotating) around the crank portion 109a.

Reference numeral 133 denotes a rear housing which constitutes a discharge chamber 134 for smoothing the refrigerant discharged from the working chamber V together with the shell 111.
Is fixed to the middle housing 107 with bolts 140 together with the shell 111. Reference numeral 135 denotes a discharge port for connecting the discharge chamber 134 to the working chamber V located substantially at the center of the shuttle (fixed scroll).
A reed valve-like discharge valve (not shown) for preventing the refrigerant discharged to the working chamber V from flowing back to the working chamber V, and a stopper 136 for regulating the maximum opening of the discharge valve are provided.

Next, features of the compressor 100 according to the present embodiment will be described. In the present embodiment, the first magnet 121 and the middle housing 1 embedded in the orbiting scroll 114
Since the repulsive force is generated between the second magnet 122 and the second magnet 122, the thrust receiving portion 120 is moved by the repulsive force between the two magnets 121 and 122.
14 is subjected to a thrust force.

Therefore, as described in the above publication, the orbiting scroll 114 is not sealed so that the discharge pressure refrigerant does not leak from the back pressure space Bv (see FIG. 2) to the suction side of the compression mechanism Cp. Since the acting thrust force can be received, the thrust force acting on the thrust receiving portion can be reduced without lowering the efficiency of the compressor 100.

Since the thrust force acting on the orbiting scroll 114 can be reduced (reduced), the sliding loss (friction loss) of the orbiting scroll 114 (end plate portion 114b) is reduced, and the efficiency of the compressor 100 is reduced. And the orbiting scroll 114 (end plate 114
c) Or, the durability (reliability) of the compressor 100 can be improved by suppressing wear of the middle housing 107.

In the above-mentioned embodiment, the electric motor Mo and the scroll type compression mechanism Cp are integrated hermetic electric compressors.
An open-type compressor in which the compressor o and the like and the compression mechanism Cp are separate bodies may be used. Further, in the above embodiment, the compressor according to the present invention is applied to a supercritical refrigeration cycle using carbon dioxide as a refrigerant, but the present invention is not limited to this.
For example, the present invention can be applied not only to a heat pump cycle and a refrigeration cycle using a refrigerant used in a supercritical region such as ethylene, ethane, or nitrogen oxide, but also to a cycle using HFC134a (CFC) as a refrigerant.

Further, in the above-described embodiment, the pin-ring type rotation preventing mechanism including the rotation preventing pin 132 and the ring portion 114c is used. However, another rotation preventing mechanism may be used. Further, in the above-described embodiment, the two magnets 121 and 122 are permanent magnets. However, other magnets such as electromagnets may be used.

Furthermore, in the above-described embodiment, the diameter of the first magnet 121 is smaller than the diameter of the second magnet 122.
The diameter of 21 may be larger than the diameter of second magnet 122.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a supercritical refrigeration cycle.

FIG. 2 is a cross-sectional view of the compressor according to the embodiment.

FIG. 3 is a front view of the orbiting scroll as viewed from an end plate portion side.

FIG. 4 is a front view of the middle housing as viewed from the orbiting scroll side.

[Explanation of symbols]

107: middle housing (fixed portion), 114: orbiting scroll (orbiting portion), 120: thrust receiving portion, 121
... a first magnet, 122 ... a second magnet.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masafumi Nakajima 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation (72) Inventor Takeshi Takei 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Denso Corporation (72) Inventor Kazuhide Uchida 14 Iwatani, Shimowasukamachi, Nishio City, Aichi Prefecture Inside (72) Inventor Sadahisa Onimaru 14 Iwatani, Shimowasukamachi, Nishio City, Aichi Prefecture Japan Auto Parts General Co., Ltd. Within the research institute (72) Inventor Kimura Narihide 14 Iwatani, Shimowakaku-cho, Nishio-shi, Aichi F-term in Japan Auto Parts Research Laboratory (reference) 3H039 AA04 AA12 BB00 BB04 BB28 CC08 CC21 CC33

Claims (4)

[Claims] 1. A compressor for sucking and compressing a fluid, comprising: a housing (107); a fixed portion (111) fixed to the housing (107); and a fluid sucked together with the fixed portion (111). A swivel part (114) that constitutes a working chamber (V) to be compressed and swivels with respect to the fixed part (111) to increase or decrease the volume of the working chamber (V); A thrust force orthogonal to the turning direction of the turning portion (114) of the compression reaction force acting on the thrust portion, and a thrust receiving portion (120) for rotatably supporting the turning portion (114); The receiving part (120) is provided with the turning part (11).
4) A first magnet (121) that is disposed at a portion facing the housing (107) and exerts a magnetic force, and is disposed at a portion of the housing (107) corresponding to the first magnet (121). A compressor provided with a second magnet (122) for providing a repulsive force to the first magnet (121). 2. A compressor for suctioning and compressing a fluid, comprising: a housing (107); a fixed scroll (111) fixed to the housing (107) and having a spiral tooth (112); The fixed scroll (11) includes a spiral-shaped tooth (113) that constitutes a working chamber (V) that comes into contact with a tooth (112) of the fixed scroll (111) to suck and compress a fluid.
1) orbiting scroll (114) for expanding or reducing the volume of the working chamber (V) by orbiting; and of the compression reaction force acting on the orbiting scroll (114), While receiving a thrust force orthogonal to the turning direction, the turning scroll (1
Thrust receiving portion (120) for supporting pivotably 14)
The thrust receiving portion (120) is disposed at a portion of the orbiting scroll (114) facing the housing (107), and a first magnet (12) that exerts a magnetic force.
1) and a second portion, which is disposed in a portion of the housing (107) corresponding to the first magnet (121) and applies a repulsive force to the first magnet (121).
A compressor comprising a magnet (122). 3. The compressor (100) according to claim 1, wherein the refrigerant is sucked and compressed, and the refrigerant discharged from the compressor (100) is cooled, and the internal pressure is equal to or higher than the critical pressure of the refrigerant. A radiator (200), a decompressor (300) for decompressing the refrigerant flowing out of the radiator (200), and an evaporator (400) for evaporating the refrigerant flowing from the decompressor (300). A supercritical refrigeration cycle having 4. The supercritical refrigeration cycle according to claim 3, wherein carbon dioxide is used as the refrigerant.