JP2004301090A - Electric compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric compressor preventing generation of mixed liquid whose electric insulation characteristic is lowered by mixing a plurality of kinds of lubricating oil with liquid refrigerant within a motor housing during normal operation of a compressor to prevent electric leak of a stator coil of an electric motor. <P>SOLUTION: In a housing 11, a back pressure chamber 41 is partitioned to be defined between the movable scroll member 28 and a shaft support member 15 disposed to a housing 11 on a back face side of a base plate 28a of a movable scroll member 28. The back pressure chamber 41 communicates with a first oil reservoir 39 disposed in a discharge chamber 35, through a pressure oil supply passage 42. The back pressure chamber 41 communicates with a second oil reservoir 53 partitioned to be formed on an outer peripheral side of the discharge chamber 35, through a lubrication passage 54 having a control valve 55. The second oil reservoir 53 communicates with an intake chamber 33 formed on an outer peripheral side of scroll walls through an oil return passage formed to a base plate 24a of a fixed scroll member 24. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric compressor used for a vehicle air conditioner, for example.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in an electric scroll compressor used for a vehicle air conditioner, a fixed scroll member including a substrate and a spiral wall fixed in a housing, and a movable scroll including a substrate and a spiral wall meshed with the spiral wall of the fixed scroll member. And a scroll member. When the electric motor accommodated in the housing is operated and the movable scroll member is turned, the compression chamber formed between the two spiral walls is moved to the center side of the spiral wall while reducing the volume, and the refrigerant gas Is performed.
[0003]
In order to improve the hermeticity of the compression chamber, the electric scroll compressor lubricates a turning drive mechanism for turning the movable scroll member and resists a thrust direction compression reaction force acting on the movable scroll member. A back pressure chamber is formed on the back side of the substrate of the movable scroll member so as to cover the orbiting drive mechanism, and lubricating oil corresponding to the discharge pressure stored at the bottom of the discharge chamber is guided to the back pressure chamber; Is biased toward a fixed scroll member. (For example, see Patent Document 1)
In the above-described electric scroll compressor, the lubricating oil provided for lubrication of the orbiting drive mechanism and the back pressure application in the back pressure chamber is dropped by its own weight into the motor housing chamber through an oil extraction passage having a throttle, After being temporarily stored in a storage section formed at the bottom of the motor accommodating chamber, it is transferred through a transfer path to the suction section side of a compression mechanism constituted by fixed and movable scroll members.
[0004]
[Patent Document 1]
JP-A-2002-95369
[0005]
[Problems to be solved by the invention]
However, it has been found that the following problems occur when the conventional electric scroll compressor is used for a vehicle air conditioner. In the conventional product, a lubricating oil reservoir is formed at the bottom of the motor housing chamber, so that a mixed liquid of lubricating oil and liquid refrigerant is stored in the lubricating oil reservoir such as when a large amount of liquid refrigerant returns from the refrigeration circuit. There is a case where the motor stays and the coil of the motor is immersed in the mixed solution. When an electric compressor is used, a lubricating oil (in general, POE: polyol ester is used) that can ensure sufficient insulation even when mixed with a liquid refrigerant is used. Although there is no problem, in the case of vehicle air conditioners, lubricating oil for the belt drive compressor during maintenance and inspection (PAG: a lubricating oil called polyalkylene glycol, which extremely deteriorates insulation when mixed with liquid refrigerant) May be mixed in, and if the connection portion of the motor or the stator coil is immersed in such a mixed solution having reduced insulation, electric leakage may occur.
[0006]
By the way, the discharge chamber of the electric scroll compressor is filled with high-pressure discharge refrigerant gas, but it is desirable to increase the volume from the viewpoint of reducing discharge pulsation. However, when the volume of the discharge chamber is increased, the high pressure of the discharged refrigerant gas acts on the substrate of the fixed scroll member, and the substrate is deformed. Due to this deformation, the sealing performance of the sliding surface between the end surface of the spiral portion of the fixed scroll member and the substrate of the movable scroll member is reduced, and the compression efficiency is reduced. In order to prevent this, a low-pressure gas region into which the suction refrigerant gas enters is defined by the partition wall outside the discharge chamber. However, conventionally, this low-pressure gas region has not been used for other purposes.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems in the conventional technology, and to mix a plurality of types of lubricating oils and a liquid refrigerant in a motor accommodating chamber during normal operation of a compressor to reduce the electrical insulation characteristics of the mixed liquid. Is not generated, it is possible to prevent defects of the stator coil of the electric motor that orbits the movable scroll member and leakage caused by the mixed liquid beforehand, and to effectively use the low-pressure gas area, which was conventionally an empty space. Another object of the present invention is to provide an electric compressor that can be used for a motor.
[0008]
[Means for Solving the Problems]
To achieve the above object, the invention according to claim 1 accommodates an electric motor in a housing, accommodates a compression mechanism operated by the electric motor to compress gas, and accommodates the electric motor. A first oil storage chamber provided in a discharge chamber, a second oil storage chamber partitioned around the discharge chamber, and a first oil storage chamber. A connection passage connecting the storage chamber and the second oil storage chamber, a flow restricting means provided in the connection passage, and an oil return passage communicating the second oil storage chamber with the suction chamber of the compressor. The gist is that the bottom of the motor accommodating chamber and the suction chamber of the compressor are connected by a fluid passage.
[0009]
According to a second aspect of the present invention, in the first aspect, the motor accommodating chamber is a gas suction passage, and the gas is guided from the bottom of the motor housing chamber to the suction chamber by the fluid passage. I do.
[0010]
According to a third aspect of the present invention, in the first or second aspect, the compressor comprises a fixed scroll member comprising a substrate and a spiral wall fixed to the housing, and the substrate and the spiral wall meshed with the spiral wall of the fixed scroll member. The movable scroll member is turned by the electric motor to move the compression chamber formed between the spiral walls to the center of the spiral wall while reducing the volume, thereby compressing the gas. The point is that the scroll format is used.
[0011]
According to a fourth aspect of the present invention, in the third aspect, a back pressure chamber is defined and formed between the movable scroll member and a fixed wall provided in a housing on the back side of the substrate of the movable scroll member. The pressure chamber and the first oil storage chamber provided in the discharge chamber are communicated via a pressure oil supply passage as a connection passage requiring a throttle, and the back pressure chamber and the second oil storage chamber are throttled or adjusted. The gist is that the second oil storage chamber and the suction chamber formed on the outer peripheral sides of the spiral walls are communicated with each other through an oil return passage, which is communicated via an oil extraction passage provided with a valve.
[0012]
(Action)
According to the first aspect of the present invention, the lubricating oil flows from the first oil storage chamber into the second oil storage chamber partitioned and formed in the motor storage chamber through the connection passage and the flow rate restricting means, and the oil return passage from the second oil storage chamber. Through to the suction chamber. On the other hand, since the bottom of the motor storage chamber and the suction chamber of the compressor are communicated by the fluid passage, the liquid refrigerant does not stay at the bottom of the motor storage chamber during the normal operation of the electric compressor. Therefore, even when lubricating oil having low insulation is mixed with lubricating oil having high insulating properties for electric use, a plurality of types of lubricating oil and liquid refrigerant are mixed at the bottom of the motor accommodating chamber, resulting in a mixture having reduced electrical insulation characteristics. No liquid is generated, and it is possible to reliably prevent electric leakage caused by the mixed liquid. Further, the necessary and sufficient lubricating oil can be stored in the first oil storage chamber and the second oil storage chamber, and the lubricating oil is reliably supplied to the suction chamber, and poor lubrication is eliminated to reduce the sliding surface of the compression mechanism. Lubrication can be performed properly.
[0013]
In particular, according to the first aspect of the present invention, the low-pressure gas region of the refrigerant gas, which is an empty space defined around the discharge chamber, can be effectively used as the second oil storage chamber.
[0014]
According to a second aspect of the present invention, in addition to the function of the first aspect, gas is sucked from the refrigeration circuit into the bottom of the motor housing chamber, and the gas is guided to the suction chamber through the fluid passage. Therefore, even if the liquid refrigerant returns from the refrigeration circuit into the motor housing during the normal operation of the electric compressor, the liquid refrigerant is sucked into the suction chamber of the compression mechanism without staying in the housing, thereby preventing the above-described leakage. .
[0015]
According to the third aspect of the present invention, in the scroll-type electric compressor, it is possible to reliably prevent the electric leakage caused by the above-mentioned liquid mixture.
According to a fourth aspect of the present invention, in addition to the effect of the third aspect of the present invention, lubricating oil is introduced from the first oil storage chamber into the back pressure chamber via the pressure oil supply passage during normal operation. The pressure in the back pressure chamber is increased, the movable scroll member is pressed toward the fixed scroll member, and the seals on the sliding surfaces of both scroll members are held. The lubricating oil in the back pressure chamber is supplied to the second oil storage chamber by a throttle or a control valve provided in the oil extraction passage. The lubricating oil stored in the second oil storage chamber is returned to the suction chamber by the oil return passage, and is used for lubrication of the sliding surface of the compression mechanism.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment in which the present invention is embodied in an electric scroll compressor used in a vehicle air conditioner will be described in detail with reference to the drawings.
[0017]
As shown in FIG. 1, a housing 11 of the electric scroll compressor is configured by joining and fixing a first housing component 12 and a second housing component 13 made of an aluminum alloy die-cast casting with bolts. The first housing component 12 includes a large-diameter tubular portion 12a, a small-diameter tubular portion 12b integrally formed at the left end of the large-diameter tubular portion 12a, and a bottom portion 12c integrally formed at the left-end portion of the small-diameter tubular portion 12b. This forms a bottomed horizontal cylinder. The second housing component 13 is formed in a closed horizontal cylindrical shape. Inside the housing 11, a closed space 14 surrounded by the two housing components 12, 13 is formed.
[0018]
At the center of the inner wall surface of the bottom portion 12c of the first housing component 12, a cylindrical shaft support portion 12d is integrally provided to protrude. On the opening end side of the large-diameter cylindrical portion 12a of the first housing component 12, a shaft support member 15 as a fixed wall having a through hole 15a formed in the center portion is fitted and fixed. A rotating shaft 16 is housed in the first housing component 12, and a left end portion thereof is rotatably supported by the bearing portion 12d via a bearing 17. The right end of the rotating shaft 16 is rotatably supported via a bearing 18 in an insertion hole 15 a of the shaft support member 15. A seal member 19 for sealing the rotary shaft 16 is interposed between the shaft support member 15 and the rotary shaft 16. Therefore, in the closed space 14, the motor housing chamber 20 is partitioned on the left side in the drawing with the shaft support member 15 as a partition.
[0019]
In the motor accommodating chamber 20, a stator 21 having a coil 21a is provided on the inner peripheral surface of the small-diameter cylindrical portion 12b of the first housing component 12. A rotor 22 is fixed to the rotating shaft 16 in the motor accommodating chamber 20 so as to be located on the inner peripheral side of the stator 21. The electric motor 23 is constituted by the small-diameter cylindrical portion 12b, the shaft support member 15, the rotating shaft 16, the stator 21, the rotor 22, and the like. By supplying power to the coil 21a of the stator 21, the rotating shaft 16 and the rotor 22 are integrally rotated.
[0020]
A fixed scroll member 24 is accommodated and arranged in the first housing component 12 at the opening end side of the large-diameter cylindrical portion 12a. The fixed scroll member 24 has a cylindrical outer peripheral wall 24b integrally formed laterally on the outer peripheral side of a disk-shaped substrate 24a, and an inner peripheral side of the outer peripheral wall 24b on the front surface (left side in FIG. 1) of the substrate 24a. Is integrally formed with a fixed spiral wall 24c (see FIG. 2). The fixed scroll member 24 is joined to a flange portion 15b integrally formed on the outer periphery of the shaft support member 15 with the distal end surface of the outer peripheral wall 24b (see FIG. 4). Accordingly, the enclosed space 14 is surrounded by the substrate 24 a of the fixed scroll member 24, the outer peripheral wall 24 b, and the shaft support member 15, and the rotation shaft 16 is sealed by the seal member 19, so that the shaft support member 15 and A scroll housing chamber 25 is defined between the fixed scroll members 24.
[0021]
An eccentric shaft 26 is provided on the distal end surface of the rotary shaft 16 at a position eccentric from the axis L of the rotary shaft 16 so as to be located in the scroll accommodating chamber 25. A bush 27 is externally fitted and fixed to the eccentric shaft 26. A movable scroll member 28 accommodated in the scroll accommodation chamber 25 is rotatably supported by the bush 27 via a bearing 29 so as to face the fixed scroll member 24. The movable scroll member 28 includes a disk-shaped substrate 28a and a movable scroll wall 28b integrally formed on the front surface (the right side in FIG. 1) of the substrate 28a. An annular ridge 28c, which is annular when viewed from the thrust direction, is integrally provided on the outer peripheral edge of the substrate 28a toward the flange 15b (see FIG. 4). The surface of the movable scroll member 28 is plated with nickel phosphorus (Ni-P).
[0022]
The fixed scroll member 24 and the movable scroll member 28 are meshed with each other via scroll walls 24c and 28b in the scroll accommodating chamber 25, and the leading end surfaces of the scroll walls 24c and 28b are formed on the other scroll members 24 and 28. It is in contact with the substrates 24a and 28a. Therefore, the substrate 24a and the fixed spiral wall 24c of the fixed scroll member 24 and the substrate 28a and the movable spiral wall 28b of the movable scroll member 28 define the compression chamber 30 in the scroll storage chamber 25.
[0023]
A rotation preventing mechanism 31 is provided between the substrate 28a of the movable scroll member 28 and the shaft support member 15 facing the substrate 28a. The rotation preventing mechanism 31 is provided with a plurality of annular holes 28d provided on the outer peripheral portion of the back surface of the substrate 28a in the movable scroll member 28 and a plurality (only one is shown in the drawing) of the flange portion 15b of the shaft support member 15. And a pin 32 loosely fitted in each of the annular holes 28d.
[0024]
In the scroll housing chamber 25, a suction chamber 33 is defined between the outer peripheral wall 24b of the fixed scroll member 24 and the outermost peripheral part of the movable scroll wall 28b of the movable scroll member 28. In the fixed scroll member 24, on the lower side of the outer peripheral surface of the outer peripheral wall 24b, as shown in FIG. On the lower inner peripheral surface of the large-diameter cylindrical portion 12a of the first housing component 12, two concave portions 12e are formed symmetrically to correspond to the two concave portions 24d. The gap between the inner peripheral surface of the concave portion 12e and the outer peripheral surface of the flange portion 15b of the shaft support member 15 and the concave portion 24d of the outer peripheral wall 24b form the lower space (bottom portion) of the motor housing chamber 20 and the suction chamber 33. The suction passage 34 is formed as a fluid passage communicating with the suction passage.
[0025]
A suction port 12f is formed in the outer periphery of the left end of the large-diameter cylindrical portion 12a of the first housing component 12 so as to communicate the motor housing chamber 20 with the outside. An external pipe connected to an evaporator of an external refrigerant circuit (not shown) is connected to the inlet 12f. Accordingly, low-pressure refrigerant gas is introduced from the external refrigerant circuit into the suction chamber 33 through the suction port 12f, the motor housing chamber 20 having a function as a suction passage, and the suction passage 34. Although not shown, a plurality of grooves are formed in the outer peripheral surface of the stator 21 in the thrust direction, and serve as passages for the refrigerant gas.
[0026]
A discharge chamber 35 is defined between the second housing component 13 and the fixed scroll member 24. A discharge hole 24e is formed at the center of the substrate 24a of the fixed scroll member 24, and the center compression chamber 30 and the discharge chamber 35 are connected through the discharge hole 24e. In the discharge chamber 35, the fixed scroll member 24 is provided with a discharge valve 37 composed of a reed valve for opening and closing the discharge hole 24e. The opening of the discharge valve 37 is regulated by a retainer 38 fixedly arranged on the fixed scroll member 24. A discharge port 13 a communicating with the discharge chamber 35 is formed in the second housing component 13. An external pipe connected to a condenser of an external refrigerant circuit (not shown) is connected to the discharge port 13a. An oil separator 36 for separating lubricating oil contained in high-pressure refrigerant gas is attached to the discharge port 13a. Therefore, the high-pressure refrigerant gas in the discharge chamber 35 is led to the external refrigerant circuit via the discharge port 13a in a state where the lubricating oil is separated by the oil separator 36. At the bottom of the discharge chamber 35, a first oil storage chamber 39 for storing the lubricating oil separated by the oil separator 36 is formed.
[0027]
Therefore, when the rotary shaft 16 is rotated by the electric motor 23, the movable scroll member 28 is turned around the axis of the fixed scroll member 24 (the axis L of the rotary shaft 16) via the eccentric shaft 26. At this time, the orbiting scroll member 28 is prevented from rotating by the rotation preventing mechanism 31 and only the turning movement is allowed. By the orbital movement of the movable scroll member 28, the compression chamber 30 is moved from the outer peripheral side of the scroll walls 24c and 28b of the scroll members 24 and 28 to the center side while reducing the volume, so that the compression chamber 30 is moved from the suction chamber 33 to the compression chamber. The compression of the low-pressure refrigerant gas taken in 30 is performed. The compressed high-pressure refrigerant gas is discharged from the discharge hole 24e to the discharge chamber 35 via the discharge valve 37.
[0028]
As shown in FIGS. 1 and 4, a back pressure chamber 41 is defined in the scroll housing chamber 25 on the rear side of the substrate 28 a of the movable scroll member 28. The back pressure chamber 41 and the first oil storage chamber 39 below the discharge chamber 35 as a discharge pressure area are communicated via a pressure oil supply passage 42 as a connection passage having a throttle 42a as a flow restricting means in the middle. I have. Accordingly, the movable scroll member 28 is urged toward the fixed scroll member 24 by the high-pressure lubricating oil containing a small amount of the refrigerant gas supplied from the first oil storage chamber 39 at the bottom of the discharge chamber 35 to the back pressure chamber 41. Will be done.
[0029]
As shown in FIGS. 1, 3, and 4, a metal such as SK material is provided between the flange portion 15 b of the shaft support member 15 and the outer peripheral wall 24 b of the fixed scroll member 24 in the scroll storage chamber 25. A donut plate-shaped elastic body 51 made of a material is provided. The outer periphery of the elastic body 51 is fixed in the scroll storage chamber 25 by being clamped at a joint portion between the flange portion 15b of the shaft support member 15 and the outer peripheral wall 24b of the fixed scroll member 24.
[0030]
As shown in FIG. 5, an arc-shaped long hole 51a is formed through the outer periphery of the elastic body 51. The space surrounded by the long hole 51a, the joint surface 15c of the flange portion 15b of the shaft support member 15, and the distal end surface of the outer peripheral wall 24b of the fixed scroll member 24 is the first oil storage chamber 39, the back pressure chamber 41, And a part (throttle 42a) of the pressure oil supply passage 42 that connects The lower end of the elongated hole 51a is communicated with the first oil storage chamber 39 by an oil passage 24f provided in an outer peripheral wall 24b of the fixed scroll member 24. The upper end of the elongated hole 51a communicates with the back pressure chamber 41 by an annular groove 15d and a linear groove 15e formed on the joint surface 15c of the shaft support member 15. The oil pressure passage 42 is formed by the oil passage 24f, the long hole 51a, the grooves 15d, 15e, and the like.
[0031]
As shown in FIG. 4, the elastic body 51 is interposed in a state of being elastically deformed by the annular ridge 28c of the movable scroll member 28. Accordingly, the sealing of the contact surface between the elastic body 51 and the annular ridge 28c is maintained by the elastic force of the elastic body 51, and the movable scroll member 28 is pressed against the fixed scroll member 24 by the elastic force.
[0032]
As shown in FIGS. 1 and 3, a closed wall 24g is formed integrally with the rear surface of the substrate 24a of the fixed scroll member 24, and the second housing component 13 is formed corresponding to the partitioned wall 24g. Is also integrally formed with the partition wall 13b. As shown in FIG. 3, a housing groove m is formed in the distal end surface of the partition wall 24g, and a seal ring 52 for sealing with the distal end surface of the partition wall 13b is fitted in the groove m. As shown in FIGS. 1 and 3, the discharge chamber 35 is formed inside the two partition walls 24 g and 13 b, and the outer peripheral surfaces of the two partition walls 24 g and 13 b and the inner peripheral surface of the second housing structure 13 are formed. A second oil storage chamber 53 is defined between the two. The second oil storage chamber 53 and the back pressure chamber 41 communicate with each other through an oil extraction passage 54 provided on the flange portion 15b of the shaft support member 15 and the outer peripheral wall 24b of the fixed scroll member 24. As shown in FIG. 5, the oil extraction passage 54 has a concave portion 15f formed by cutting out the joint surface 15c of the shaft support member 15 so as to communicate with the groove 15d, and a concave portion 15f on the outer periphery of the elastic body 51 corresponding to the concave portion 15f. The hole 51b is formed by the penetrated hole 51b and the passage 24h penetrating through the outer peripheral wall 24b of the fixed scroll member 24 corresponding to the hole 51b. A plurality of pin holes 51 c through which the pins 32 of the rotation preventing mechanism 31 are inserted are formed in the inner peripheral portion of the elastic body 51.
[0033]
In the middle of the oil extraction passage 54 (passage 24h) on the outer peripheral wall 24b of the fixed scroll member 24, the oil extraction passage 54 is formed in accordance with the difference between the pressure in the back pressure chamber 41 and the pressure in the second oil storage chamber 53. A control valve 55 for adjusting the opening is provided. The control valve 55 is constituted by a ball valve 56 and a coil spring 57, and is operated so as to keep the difference between the pressure in the back pressure chamber 41 and the pressure in the second oil storage chamber 53 constant. Therefore, in the normal operation state of the electric scroll compressor, the pressure of the back pressure chamber 41, that is, the urging force of the movable scroll member 28 based on the pressure of the back pressure chamber 41 is kept substantially constant by the operation of the control valve 55. It becomes. The lubricating oil in the back pressure chamber 41 is stored in the second oil storage chamber 53 through the oil extraction passage 54 and the control valve 55.
[0034]
As shown in FIG. 3, an oil return passage 24i is formed in the substrate 24a of the fixed scroll member 24 so as to communicate the bottom of the second oil storage chamber 53 with the suction chamber 33. The gas separated from the lubricating oil stored in the second oil storage chamber 53 is supplied to the suction chamber 33 on the substrate 24a so that the upper part of the second oil storage chamber 53 and the upper space of the suction chamber 33 communicate with each other. A gas return passage 24j for guiding is formed through. Therefore, the lubricating oil stored in the second oil storage chamber 53 is guided into the suction chamber 33 through the oil return passage 24i by the suction action based on the orbital movement of the movable scroll member 28, and is transferred to the compression chamber 30 together with the refrigerant gas. It is taken in and lubricates the sliding surface of the compression mechanism. The refrigerant gas separated from the lubricating oil in the upper part of the second oil storage chamber 53 is guided to the suction chamber 33 from the gas return passage 24j.
[0035]
FIG. 3 shows a state in which the second housing component 13 has been removed from the opening end surface of the large-diameter cylindrical portion 12a of the first housing component 12. As shown in FIG. 3, the substrate 24 a is formed with a concave portion 24 d that forms the suction passage 34, so that the outer joint of the second housing component 13 is formed so as to partition the concave portion 24 d and the second oil storage chamber 53. The shape of the surface is set. A gasket 58 for partitioning is interposed between the outer joint surface and the open end surface of the large-diameter cylindrical portion 12a of the first housing component 12, as shown by a two-dot chain line in FIG.
[0036]
As shown in FIG. 1, an accommodating concave portion 61 capable of accommodating a predetermined amount of lubricating oil or liquid refrigerant below the coil 21a is formed at the bottom of the large-diameter cylindrical portion 12a of the first housing structure 12 so as to bulge downward. Have been.
[0037]
The present embodiment having the above configuration has the following effects.
(1) In the embodiment, the discharge chamber 35 is formed so as to be positioned between the second housing component 13 and the substrate 24a of the fixed scroll member 24, and the second oil storage chamber is provided outside the discharge chamber 35. 53 were sectioned. Further, the lubricating oil is temporarily stored in the second oil storage chamber 53 from the back pressure chamber 41 through the oil extraction passage 54 and the control valve 55. Therefore, lubricating oil can be supplied from the second oil storage chamber 53 to the suction chamber 33 through the oil return passage 24i, and the lubrication of the sliding surface of the compression mechanism can be ensured without poor lubrication.
[0038]
(2) In the above-described embodiment, the low-pressure gas area, which was conventionally a vacant space, can be used as the second oil storage chamber 53, and there is no need for a dedicated component constituting the second oil storage chamber 53, thereby reducing the manufacturing cost. Can be reduced. The second oil storage chamber 53 is provided to reduce the volume of the discharge chamber 35 to reduce the discharge pressure acting on the substrate of the fixed scroll member, and to prevent deformation of the substrate. Only the suction refrigerant gas stayed.
[0039]
(3) In the embodiment, the lubricating oil is stored in the second oil storage chamber 53. For this reason, the lubricating oil derived from the back pressure chamber 41 is not stored at the bottom of the motor housing chamber 20, and even if the electric scroll compressor is of a type that introduces refrigerant gas into the motor housing chamber 20, The two or more kinds of lubricating oils and the liquid refrigerant described in the above paragraph are not mixed to form a mixed liquid with reduced electrical insulation. Accordingly, it is possible to prevent the leakage due to the mixed liquid caused by the defect of the coil 21a of the electric motor 23.
[0040]
Further, since the lubricating oil is stored in the second oil storage chamber 53, the lubricating oil is stably supplied to the suction chamber 33, the poor lubrication state is eliminated, and the lubrication of the sliding surface of the compression mechanism is properly performed. Can be done.
[0041]
(4) In the above-described embodiment, the motor storage chamber 20 functions as a refrigerant gas suction passage, and the refrigerant gas is sucked into the suction chamber 33 from the bottom of the motor storage chamber 20. For this reason, it is possible to prevent the lubricating oil or the liquid refrigerant that is stagnation at the bottom of the motor accommodating chamber 20 from moving to the suction chamber 33 together with the refrigerant gas and stagnate in the normal operation state. Electric leakage of the coil 21a of the electric motor 23 due to the liquid can be prevented.
[0042]
(5) In the above-described embodiment, the large-diameter tube portion 12a is formed in front of the small-diameter tube portion 12b that forms the motor housing chamber 20, and the housing recess 61 that can store lubricating oil is formed below the large-diameter tube portion 12a. did. For this reason, even if lubricating oil and liquid refrigerant are stored to some extent in the motor housing chamber 20 due to the physical characteristics of the air conditioner due to the temporary shutdown of the compressor, the coil 21a may be immersed in the mixed liquid. Therefore, the problem of electric leakage of the coil 21a when the compressor is restarted can be eliminated.
[0043]
(6) Since the surface of the movable scroll member 28 is plated with nickel-phosphorus (Ni-P), for example, the high-speed operation of the compressor is continued, and the fixed scroll member 24 when the lubricating oil becomes insufficient is used. The durability of the sliding surface of the movable scroll member 28 can be improved.
[0044]
(7) The movable scroll member 28 is urged toward the fixed scroll member 24 by the high-pressure refrigerant gas supplied to the back pressure chamber 41. That is, the movable scroll member 28 is urged toward the fixed scroll member 24 not only by the urging force based on the elastic deformation of the elastic body 51 but also by the urging force based on the pressure of the back pressure chamber 41. Therefore, for example, in the normal operation state of the electric scroll compressor, it is possible to surely oppose the thrust direction compression reaction force acting on the movable scroll member 28, and as in the present embodiment, each of the spiral walls 24c, 28b Even if a seal member (for example, a chip seal) is not provided on the distal end surface, the hermeticity of the compression chamber 30 can be reliably maintained.
[0045]
The present invention can be implemented in the following modes without departing from the spirit of the present invention.
The shape of the partition walls 24g, 13b shown in FIG. 3 as viewed from the thrust direction may be changed to, for example, a circle, an ellipse, a square, or an arbitrary shape.
[0046]
In the above embodiment, the gas return passage 24j may be omitted.
In the above embodiment, the arrangement position of the oil extraction passage 54 may be changed from the intermediate height position of the second oil storage chamber 53 to the upper end or the lower part.
[0047]
In the above-described embodiment, the suction passage 34 that connects the motor housing chamber 20 and the suction chamber 33 may be changed to the upper part of the large-diameter cylindrical portion 12a and the outer peripheral wall 24b, or may be formed on both upper and lower sides. .
[0048]
In the above-described embodiment, the electric motor 23 is disposed horizontally in the horizontal direction. However, the electric motor 23 may be disposed horizontally in the vertical direction at an inclination angle of, for example, 10 ° with respect to the horizontal line.
[0049]
In the above embodiment, the suction port 12f formed in the first housing component 12 is eliminated, and the suction port is provided in the outer peripheral portion of the large-diameter cylindrical portion 12a and the outer peripheral wall 24b of the fixed scroll member 24, and the refrigerant flows into the suction chamber 33. Gas may be introduced.
[0050]
In the above embodiment, a throttle having a smaller passage area than the throttle 42a may be used instead of the control valve 55 provided in the oil extraction passage 54.
-The accommodation recess 61 may be omitted.
[0051]
In the above embodiment, the electric scroll compressor is embodied, but an electric compressor such as an electric swash plate compressor, an electric vane compressor, an electric piston compressor, or both an electric motor and an engine used in a vehicle. The present invention may be embodied in various types of compressors of a so-called hybrid type as a driving source.
[0052]
The technical idea that can be grasped from the embodiment will be described.
(1) The electric compressor according to any one of claims 1 to 4, wherein a surface of the movable scroll member is plated with nickel and phosphorus.
[0053]
(2) The substrate of the movable scroll member according to any one of claims 1 to 4, wherein the substrate of the movable scroll member is urged in a thrust direction by an elastic body having a donut plate shape in the scroll accommodating chamber. An electric compressor that seals the back pressure chamber with an annular ridge formed on the back surface of the electric compressor.
[0054]
【The invention's effect】
According to the present invention having the above configuration, even when the liquid refrigerant returns from the refrigeration circuit into the motor housing during the normal operation of the electric compressor, it is sucked into the suction chamber of the compression mechanism without staying in the motor housing. Therefore, even when lubricating oil having low insulation is mixed with lubricating oil having high insulating properties for electric power, a mixture of a plurality of types of lubricating oils and liquid refrigerant is mixed to generate a mixed liquid having reduced electric insulation characteristics. Therefore, the leakage caused by the mixed solution can be reliably prevented. In addition, necessary and sufficient lubricating oil can be stored in the first oil storage chamber and the second oil storage chamber, and reliability can be secured.
[0055]
In particular, in the present invention, the low-pressure gas region, which was conventionally a free space, can be effectively used.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view in which an electric compressor of the present invention is embodied in an electric scroll compressor.
FIG. 2 is a cross-sectional view of a compression mechanism of the electric scroll compressor.
FIG. 3 is a cross-sectional view passing through a discharge chamber of the electric scroll compressor.
FIG. 4 is an enlarged longitudinal sectional view showing the vicinity of a back pressure chamber and an elastic body.
FIG. 5 is an exploded perspective view of a shaft support member, an elastic body, and a fixed scroll member.
DESCRIPTION OF REFERENCE NUMERALS 11 housing, 12c bottom, 20 motor housing, 23 electric motor, 24 fixed scroll member, 24a, 28a substrate, 24c, 28b spiral wall, 24h, 24i, 24j passage , 28 movable scroll member, 30 compression chamber, 33 suction chamber, 34 suction passage as fluid passage, 35 discharge chamber, 39 first oil storage chamber, 41 back pressure chamber, 42 connection passage Pressure oil supply passage, 42a ... throttle as flow rate limiting means, 53 ... second oil storage chamber, 54 ... oil extraction passage, 55 ... regulating valve.

Claims (4)

An electric compressor which accommodates an electric motor in a housing, accommodates a compression mechanism operated by the electric motor to compress gas, and has a motor accommodation chamber accommodating the electric motor in a suction atmosphere. ,
A first oil storage chamber provided in the discharge chamber;
A second oil storage chamber partitioned around the discharge chamber;
A connection passage connecting the first oil storage chamber and the second oil storage chamber,
Flow rate limiting means provided in the connection passage;
An oil return passage communicating the second oil storage chamber with a suction chamber of the compressor;
An electric compressor, wherein a bottom of the motor accommodating chamber and a suction chamber of the compressor are communicated by a fluid passage. 2. The electric compressor according to claim 1, wherein the motor housing is a gas suction passage, and the fluid guides the gas from a bottom of the motor housing to the suction chamber. 3. The compressor according to claim 1 or 2, further comprising: a fixed scroll member comprising a substrate and a spiral wall, wherein the compressor is fixed to the housing; and a movable scroll member comprising the substrate and the spiral wall meshed with the spiral wall of the fixed scroll member, The movable scroll member is turned by the electric motor, and a compression chamber formed between the two spiral walls is moved to a center side of the spiral wall while reducing the volume, thereby performing a scroll type in which gas is compressed. And electric compressor. 4. The back pressure chamber according to claim 3, wherein a back pressure chamber is defined between the movable scroll member and a fixed wall provided in the housing on the back side of the substrate of the movable scroll member, and is provided in the back pressure chamber and the discharge chamber. The first oil storage chamber communicates with the first oil storage chamber via a pressure oil supply passage as a connection path requiring a throttle, and the back pressure chamber and the second oil storage chamber are connected to an oil extraction passage having a throttle or a control valve. An electric compressor, wherein the second oil storage chamber and the suction chamber formed on the outer peripheral sides of the spiral walls are communicated by an oil return passage.

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