WO2023079667A1

WO2023079667A1 - Scroll compressor and refrigeration cycle device provided with scroll compressor

Info

Publication number: WO2023079667A1
Application number: PCT/JP2021/040687
Authority: WO
Inventors: 航佐々野; 浩平達脇
Original assignee: 三菱電機株式会社
Priority date: 2021-11-05
Filing date: 2021-11-05
Publication date: 2023-05-11

Abstract

This scroll compressor includes a suction pipe that sucks refrigerant into a shell, the intake pipe has a plurality of branch pipes, and each of the plurality of branch pipes is connected to the shell so as to communicate with the interior of the shell. Some of the plurality of branch pipes are in communication with a refrigerant intake space which is on the outer peripheral side of a first spiral projection and a second spiral projection, and which takes in refrigerant before the refrigerant is taken into a compression chamber.

Description

Scroll compressor and refrigeration cycle device provided with this scroll compressor

The present disclosure relates to a scroll compressor used for refrigeration or air conditioning applications, and a refrigeration cycle device provided with this scroll compressor.

A scroll compressor has an orbiting scroll supported on the upper surface of a frame fixed inside a shell, and a fixed scroll is provided facing the orbiting scroll. The frame extends in the axial direction of the shell and has a cylindrical peripheral wall located on the outer peripheral side of the spiral teeth of the fixed scroll. A rotating shaft is attached to the orbiting scroll, and the rotating shaft is rotated by an electric motor arranged below the frame, thereby causing the orbiting scroll to perform an orbiting motion with respect to the fixed scroll, thereby separating the orbiting scroll and the fixed scroll. Refrigerant is compressed in a compression chamber formed by

A suction pipe that draws refrigerant into the shell is connected to the shell. The intake pipe is connected to the shell at a position below the frame to cool the motor with the intake refrigerant. On the outer peripheral surface of the peripheral wall of the frame, a suction port cut in a rectangular shape when viewed in the axial direction of the rotating shaft is cut in the axial direction of the rotating shaft in order to guide the refrigerant sucked into the shell below the frame to the compression chamber. is formed through the Refrigerant sucked into the shell from the suction pipe is taken into the compression chamber through the suction port and compressed in the compression chamber.

The scroll compressor with the above configuration can increase the compression efficiency by increasing the capacity of the compression chamber. For this reason, conventionally, there is a scroll compressor in which the peripheral wall of the frame is eliminated to increase the size of the orbiting scroll and expand the capacity of the compression chamber (see, for example, Patent Document 1).

WO2018/163233

However, the size of the oscillating base plate of the oscillating scroll must be such that it fits inside the intake port so as not to block the intake port provided on the frame during the oscillating motion. For this reason, the scroll compressor of Patent Document 1 cannot sufficiently expand the capacity of the compression chamber. In addition, in the scroll compressor of Patent Document 1, when trying to reduce the pressure loss (hereinafter referred to as suction pressure loss) from when the refrigerant is sucked into the shell until it is taken into the compression chamber, the opening of the suction port is increased. There is a need. In order to increase the opening of the suction port, the opening of the suction port must be expanded inward in the radial direction of the rotating shaft. Can not. In other words, in Patent Document 1, there is a problem that it is difficult to achieve both a reduction in suction pressure loss and an increase in capacity.

The present disclosure has been made in order to solve the above-described problems, and is a scroll compressor capable of achieving both reduction in suction pressure loss and increase in capacity, and a refrigeration system equipped with the scroll compressor. An object of the present invention is to provide a cycle device.

A scroll compressor according to the present disclosure includes a fixed scroll having a shell, an intake pipe for sucking refrigerant into the shell, a fixed base plate provided with a first spiral projection, and a first spiral projection engaged with the first spiral projection. 2. An oscillating scroll having an oscillating base plate provided with spiral projections and forming a compression chamber for compressing the refrigerant between the oscillating scroll and the fixed scroll; an electric motor driving the oscillating scroll; a frame that is fixed and supports the orbiting scroll on the side opposite to the compression chamber with respect to the orbiting scroll, and the refrigerant sucked into the shell from the suction pipe is introduced through the suction port formed in the frame. A scroll compressor in which refrigerant is drawn into a compression chamber and compressed after being taken into a refrigerant intake space on the outer peripheral side of a first spiral projection and a second spiral projection, wherein the suction pipe has a plurality of branch pipes. , each of the plurality of branch pipes is connected to the shell so as to communicate with the interior of the shell, and some of the plurality of branch pipes communicate with the refrigerant intake space.

A refrigeration cycle device according to the present disclosure includes the scroll compressor, the condenser, the decompression device, and the evaporator, and includes a refrigerant circuit in which refrigerant circulates.

In the scroll compressor according to the present disclosure, the suction pipe has a plurality of branch pipes, and some of the plurality of branch pipes communicate with the refrigerant intake space, so that the refrigerant is drawn into the shell. A portion of the refrigerant is taken directly into the refrigerant take-in space without passing through the intake port of the frame, and then taken into the compression chamber. Therefore, in the scroll compressor, all the refrigerant sucked into the shell is sucked into the space on the opposite side of the frame from the orbiting scroll, and the suction pressure loss is reduced compared to the configuration in which the refrigerant passes through the suction port. be able to. In this way, the scroll compressor can reduce the suction pressure loss without increasing the size of the suction port. Therefore, the scroll compressor can expand the capacity of the compression chamber. In other words, the scroll compressor and the refrigeration cycle device provided with this scroll compressor can achieve both a reduction in suction pressure loss and an increase in capacity.

1 is a front view showing an appearance of a scroll compressor according to Embodiment 1; FIG. 1 is a schematic longitudinal sectional view showing an internal structure of a scroll compressor according to Embodiment 1; FIG. 1 is a schematic perspective view showing an exploded main part of a scroll compressor according to Embodiment 1; FIG. FIG. 2 is a diagram showing a refrigerant suction path of the scroll compressor according to Embodiment 1; FIG. FIG. 7 is a diagram showing a refrigerant suction path of a scroll compressor according to Embodiment 2; FIG. 7 is a diagram showing a refrigerant circuit of a refrigeration cycle device according to Embodiment 3;

Embodiments will be described below based on the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will be omitted or simplified as appropriate.

Embodiment 1.
1 is a front view showing the appearance of a scroll compressor according to Embodiment 1. FIG. 2 is a schematic longitudinal sectional view showing the internal structure of the scroll compressor according to Embodiment 1. FIG. FIG. 3 is a schematic perspective view showing an exploded main part of the scroll compressor according to Embodiment 1. FIG. The scroll compressor according to Embodiment 1 is one of the components of a refrigerant circuit used in, for example, a refrigerator, a freezer, an air conditioner, a refrigerating device, a water heater, or the like.

The scroll compressor 100 draws in the refrigerant circulating in the refrigerant circuit, compresses it, and discharges it in a state of high temperature and high pressure. As shown in FIGS. 1 and 2, the scroll compressor 100 includes a shell 1 forming an outer shell, a frame 2, a compression mechanism section 3 having a fixed scroll 4 and an orbiting scroll 5, an electric motor 6, and a compression mechanism. and a rotary shaft 7 that connects the portion 3 and the electric motor 6 .

As shown in FIG. 1, the shell 1 is a conductive member such as metal, and is formed in a cylindrical shape having a closed space. Inside the shell 1, a frame 2, a compression mechanism section 3, an electric motor 6, and a rotating shaft 7 are accommodated. Inside the shell 1 , the compression mechanism 3 is arranged above the frame 2 and the electric motor 6 is arranged below the frame 2 . The scroll compressor 100 is a so-called low-pressure shell type in which a low-pressure refrigerant gas is once taken into the shell 1 and then compressed. Although FIG. 1 and FIG. 2 show a so-called vertical type scroll compressor that is used with the rotating shaft 7 in the direction of gravity, it may be a horizontal type scroll compressor.

The shell 1 has a cylindrical main shell 1a, a substantially hemispherical upper shell 1b that closes the upper opening of the main shell 1a, and a substantially hemispherical lower shell 1c that closes the lower opening of the main shell 1a. The upper shell 1b and the lower shell 1c are fixed to the main shell 1a by welding or the like. The shell 1 is supported by a fixed base 1d fixed to the lower shell 1c.

As shown in FIG. 3, the inner wall surface of the main shell 1a includes a large-diameter first inner wall surface 10a formed at the upper end, a second inner wall surface 10b formed below the first inner wall surface 10a, and a second inner wall surface 10b. and a third inner wall surface 10c formed below the second inner wall surface 10b. The first inner wall surface 10a, the second inner wall surface 10b, and the third inner wall surface 10c are configured such that the inner diameters thereof decrease in this order. A first step portion 11 a formed by the lower end of the first inner wall surface 10 a and the upper end of the second inner wall surface 10 b functions as a positioning portion for the fixed scroll 4 . A second step portion 11 b formed by the lower end of the second inner wall surface 10 b and the upper end of the third inner wall surface 10 c functions as a positioning portion for the frame 2 .

A suction pipe 13 for sucking refrigerant into the shell 1 is connected to the main shell 1a, as shown in FIGS. The intake pipe 13 has a plurality of branch pipes, here a main branch pipe 13a and a sub-branch pipe 13b. The main branch pipe 13a and the sub-branch pipe 13b are connected to the main shell 1a so as to communicate with the inside of the shell 1 respectively. The main branch pipe 13a and the sub-branch pipe 13b are connected by brazing or the like while being partially inserted into a hole formed in the side wall of the main shell 1a.

The main branch pipe 13a communicates with the low-pressure space 16b below the frame 2 inside the shell 1, in other words, the space on the opposite side of the frame 2 from the orbiting scroll 5. The sub-branch pipe 13b communicates with a refrigerant intake space 37, which will be described later. The main branch pipe 13a and the sub-branch pipe 13b are connected to the main shell 1a in the same phase, but it is not limited to this. The pipe diameter of the main branch pipe 13a and the pipe diameter of the sub-branch pipe 13b may be the same or different. Since the main branch pipe 13a is the suction pipe that mainly draws the refrigerant into the shell 1, if the pipe diameter of the main branch pipe 13a and the sub-branch pipe 13b are different, the pipe diameter of the main branch pipe 13a > It is desirable to satisfy the pipe diameter of the sub-branch pipe 13b.

Further, the main shell 1a is provided with a power supply section 19 for supplying power to the scroll compressor 100 as shown in FIGS. The power supply unit 19 includes a cover 19a, power supply terminals 19b, and wiring 19c. The power supply terminal 19b is a metal member, one end of which is arranged so as to be surrounded by the cover 19a, and the other end of which is arranged inside the main shell 1a. The wiring 19 c has one end connected to the power supply terminal 19 b and the other end connected to the electric motor 6 .

A discharge pipe 14 for discharging the compressed refrigerant from the shell 1 is connected to the upper shell 1b. The discharge pipe 14 is partially inserted into a hole formed in the upper portion of the upper shell 1b and connected by brazing or the like. Further, an oil reservoir 18 for storing lubricating oil is provided in the inner bottom portion of the shell 1 .

The frame 2, as shown in FIGS. 2 and 3, is a cylindrical metal frame that tapers downward in stages, and supports the orbiting scroll 5 so that it can oscillate. The outer peripheral surface of the frame 2 is fixed to the inner wall surface of the main shell 1a by, for example, shrink fitting. An annular flat surface 20 is formed on the upper surface of the frame 2 as shown in FIG. A ring-shaped thrust plate 25 made of a steel plate material such as valve steel is provided on the flat surface 20 . The thrust plate 25 functions as a thrust sliding surface of the frame 2 and supports the thrust load of the compression mechanism section 3 . The thrust plate 25 is formed to have an outer diameter slightly smaller than the inner diameter of the first inner wall surface 10a of the main shell 1a.

Further, as shown in FIG. 3 , the inside of the cylinder of the frame 2 is composed of a housing portion 21 and a main bearing portion 22 that supports the rotating shaft 7 . The housing portion 21 is provided on the upper side of the frame 2 . The main bearing portion 22 is provided on the lower side of the frame 2 .

As shown in FIG. 3, the accommodating portion 21 is formed so that the inner diameter gradually decreases downward. The accommodation portion 21 has an Oldham accommodation portion 21a at a stepped portion located on the flat surface 20 side, and a bush accommodation portion 21b at a stepped portion located on the main bearing portion 22 side. A pair of first Oldham grooves 21c are provided in the Oldham housing portion 21a and a portion of the flat surface 20 so as to face each other with the shaft hole interposed therebetween. The first Oldham groove 21c is a key groove into which a first key portion 54b of an Oldham ring 54, which will be described later, is fitted.

Further, in the frame 2, as shown in FIG. 2, an oil return pipe 24 is inserted into and fixed to an oil return hole 23 formed through the inside and outside of the frame 2. As shown in FIG. The oil return hole 23 communicates with the bush accommodating portion 21b. The oil return pipe 24 is provided to return the lubricating oil accumulated in the housing portion 21 to the oil reservoir 18 provided in the lower shell 1c. In addition, the number of the oil return hole 23 and the oil return pipe 24 is not limited to one, and a plurality of them may be provided.

As shown in FIGS. 1 and 2, the outer peripheral portion of the frame 2 is provided with a suction port 26, which is a communication passage for communicating the low-pressure space 16b and a refrigerant intake space 37, which will be described later. It is provided so as to pass through the rotating shaft 7 in the axial direction. As shown in FIG. 3, the suction port 26 is formed in an elongated shape along the circumferential direction of the inner wall surface of the main shell 1a. Refrigerant sucked into the shell 1 from the main branch pipe 13a passes through the suction port 26, is taken into the refrigerant take-in space 37, and is taken into the later-described compression chamber 30. As shown in FIG. Refrigerant sucked from the sub-branch pipe 13 b is directly taken into the refrigerant take-in space 37 and then taken into the compression chamber 30 .

In FIG. 3, the connection port 13ba of the sub-branch pipe 13b with the main shell 1a and the suction port 26 are in a positional relationship of about 45° when viewed in the axial direction about the rotation shaft 7. , a positional relationship of about 180° is preferred. In other words, the sub-branch pipe 13b is preferably connected to a side surface of the shell 1 facing the intake port 26 across the rotating shaft 7 when viewed in the axial direction of the rotating shaft 7 of the electric motor 6 . This is because the refrigerant intake ports to the plurality of compression chambers 30 configured by meshing the first spiral projection portion 4b and the second spiral projection portion 5b of the compression mechanism portion 3 are arranged around the rotating shaft 7. This is because there are two at positions of about 180° when viewed in the axial direction at an angle of about 180°. Since the connection port 13ba and the suction port 26 have a positional relationship of about 180° when viewed in the axial direction, the scroll compressor 100 balances the refrigerant intake amount of each compression chamber 30 from each refrigerant intake port. be able to.

When the sub-branch pipe 13b is connected to the side surface of the shell 1 facing the intake port 26 across the rotating shaft 7 when viewed in the axial direction of the rotating shaft 7 of the electric motor 6, the main branch pipe 13a is also connected to the sub-branch pipe. It is provided at a position that satisfies the same positional relationship as 13b. Also, although FIG. 2 shows an example of one suction port 26, there may be two, a main port and a sub port. In this case, the sub-branch pipe 13b and the main branch pipe 13a are preferably connected to the side surface of the shell 1 with reference to the intake port on the main side. That is, the sub-branch pipe 13b and the main branch pipe 13a are connected to the side surface of the shell 1 that faces the main intake port across the rotating shaft 7 when viewed in the axial direction of the rotating shaft 7 of the electric motor 6. is desirable.

The compression mechanism section 3 is driven by the electric motor 6 and has a function of compressing the refrigerant sucked from the main branch pipe 13a and the sub-branch pipe 13b. The compression mechanism section 3 includes a fixed scroll 4 and an orbiting scroll 5 . As shown in FIGS. 2 and 3, the fixed scroll 4 has a disk-shaped fixed base plate 4a and a first spiral protrusion 4b provided on the lower surface of the fixed base plate 4a. The oscillating scroll 5 has a disk-shaped oscillating base plate 5a and a second spiral projection 5b provided on the upper surface of the oscillating base plate 5a and meshing with the first spiral projection 4b. The orbiting scroll 5 is installed eccentrically with respect to the fixed scroll 4 .

The first spiral protrusion 4b of the fixed scroll 4 and the second spiral protrusion 5b of the orbiting scroll 5 are engaged with each other to form a compression chamber 30 for compressing the refrigerant. The compression chambers 30 are composed of a plurality of compression chambers whose volumes decrease from the radially outer side to the inner side of the scroll as the orbiting scroll 5 swings. The compression chamber 30 is sealed by a tip seal 41 and a rocking base plate 5a provided at the tip of the first spiral projection 4b and a tip seal 52 and a fixed bed plate 4a provided at the tip of the second spiral projection 5b. It is A coolant intake space 37 is formed between the inner wall surface of the shell 1 and the outer peripheral side of the first spiral protrusion 4b and the second spiral protrusion 5b.

The fixed scroll 4 is made of metal such as cast iron. The fixed scroll 4 is fixed to the first inner wall surface 10a by shrink fitting or the like while the outer peripheral surface of the fixed base plate 4a is supported by the first step portion 11a of the main shell 1a. Here, FIG. 2 shows an example of a so-called frame outer wall-less structure in which the frame 2 does not have a peripheral wall and the fixed scroll 4 is fixed to the inner wall surface of the shell 1, but it is not limited to this. do not have. The scroll compressor 100 may be a type of scroll compressor in which the frame 2 has a peripheral wall and the fixed scroll 4 is fixed to the peripheral wall of the frame 2 .

A discharge port 40 for discharging compressed high-temperature and high-pressure refrigerant is formed in the center of the fixed base plate 4a. A discharge chamber 15 having a discharge hole 15 a communicating with a discharge port 40 is provided on the upper surface of the fixed scroll 4 . The discharge chamber 15 is provided with a discharge valve 17 that opens and closes the discharge hole 15a according to the pressure of the refrigerant. The discharge valve 17 opens the discharge hole 15a when the refrigerant in the compression chamber 30 communicating with the discharge port 40 reaches a predetermined pressure. The compressed high-temperature, high-pressure refrigerant is discharged from the discharge port 40 into the high-pressure space 16 a above the fixed scroll 4 , passes through the discharge pipe 14 , and is discharged to the outside of the shell 1 . A groove is formed at the tip of the first spiral projection 4b, and a tip seal 41 made of hard plastic, for example, is provided in this groove.

The orbiting scroll 5 is made of metal such as aluminum. As shown in FIGS. 2 and 3, the orbiting scroll 5 revolves around the fixed scroll 4 without rotating due to an Oldham ring 54 for preventing rotation. The surface of the rocking base plate 5a on which the second spiral projection 5b is not formed (lower surface in the illustrated example) acts as a rocking scroll thrust bearing surface. A hollow cylindrical boss portion 51 is provided at the center of the orbiting scroll thrust bearing surface. A swing bearing is provided on the inner peripheral surface of the boss portion 51 . The swing bearing rotatably supports a slider 80 of the bush 8, which will be described later. The rocking bearing is a so-called journal bearing. The swing bearing is provided so that its central axis is parallel to the central axis of the rotating shaft 7 . As the eccentric shaft portion 71 of the rotating shaft 7 inserted into the boss portion 51 rotates, the orbiting scroll 5 revolves on the thrust sliding surface of the frame 2 .

A groove is formed at the tip of the second spiral projection 5b, and a chip seal 52 made of hard plastic, for example, is provided in the groove. The orbiting scroll thrust bearing surface is provided with a pair of second Oldham grooves 53 formed to face each other with the boss portion 51 interposed therebetween as shown in FIG. The second Oldham groove 53 is an oblong key groove into which a second key portion 54c of an Oldham ring 54, which will be described later, is fitted. The pair of second Oldham grooves 53 are arranged such that the line connecting the pair of second Oldham grooves 53 is perpendicular to the line connecting the pair of first Oldham grooves 21c.

The Oldham ring 54 includes a ring portion 54a, a first key portion 54b, and a second key portion 54c, as shown in FIG. The ring portion 54 a has an annular shape and is arranged in the Oldham housing portion 21 a of the frame 2 . The first key portion 54b is provided on the lower surface of the ring portion 54a. The first key portions 54b are composed of a pair and are accommodated in the pair of first Oldham grooves 21c of the frame 2, respectively. The second key portion 54c is provided on the upper surface of the ring portion 54a. The second key portions 54c are formed in pairs and are accommodated in the pair of second Oldham grooves 53 of the orbiting scroll 5, respectively. By aligning the second Oldham groove 53 of the orbiting scroll 5 with the second key portion 54c of the Oldham ring 54, the rotational position of the second spiral protrusion 5b of the orbiting scroll 5 is determined. That is, the Oldham's ring 54 positions the orbiting scroll 5 with respect to the frame 2 and determines the phase of the second spiral projection 5b with respect to the frame 2 .

Refrigerants can be used, for example, halogenated hydrocarbons with double carbon bonds in their composition, halogenated hydrocarbons without double carbon bonds, natural refrigerants, or mixtures containing them. Halogenated hydrocarbons having carbon double bonds include HFO refrigerants such as R1234yf ( _CF3CF = _CH2 ), R1234ze ( _CF3CH =CHF) or R1233zd ( _CF3CH =CHCl). Halogenated hydrocarbons without carbon double bonds include R32 ( _CH3F2 ₎ , R41 ( _CH3F ), R125 ( _C2HF3 ), _R134a ₍ _CH2FCF2 ), R143a ( _CF3CH ₃ ), HFC refrigerants such as R410A (R32/R125) or R407C (R32/R125/R134a). R32 ( _{difluoromethane} ) represented by _CH2F2 , R41, etc. are exemplified as mixed refrigerants. Natural _refrigerants include ammonia ( _NH3 ), carbon dioxide ( _CO2 ), propane ( _C3H8 ), propylene ₍ _C3H6 ), butane ( _C4H10 ) or isobutane ( _CH3 ), and the like _. . Desirably, the refrigerant has zero ozone depletion potential and low GWP.

The electric motor 6, as shown in FIG. 2, drives the compression mechanism section 3 connected via the rotating shaft 7. The electric motor 6 includes an annular stator 6a fixedly supported on the inner wall surface of the shell 1 by shrink fitting or the like, and a rotor 6b rotatably mounted facing the inner surface of the stator 6a. The stator 6a has, for example, an iron core formed by laminating a plurality of electromagnetic steel sheets, and windings are wound through an insulating layer. formed. The rotor 6b has a structure in which a permanent magnet is built in an iron core formed by laminating a plurality of electromagnetic steel sheets, and has a through hole penetrating vertically in the center.

　The rotating shaft 7 is a rod-shaped member made of metal, as shown in FIG. The rotating shaft 7 includes a main shaft portion 70 and an eccentric shaft portion 71 . The main shaft portion 70 is a shaft that constitutes the main portion of the rotating shaft 7, and is arranged so that its central axis coincides with the central axis of the main shell 1a. The main shaft portion 70 is inserted into a central through hole of the rotor 6b and fixed to the rotor 6b by shrink fitting or the like. Further, the balancer 12 eccentric with respect to the main shaft portion 70 is also fixed to the main shaft portion 70 by shrink fitting or the like. The balancer 12 rotates together with the main shaft portion 70 to cancel the imbalance with other parts. The rotating shaft 7 is freely rotatable by a main bearing 22 provided in the center of the frame 2 and a sub-bearing 90 provided in the center of a sub-frame 9 fixed to the lower part of the shell 1 by welding or the like. supported by

The eccentric shaft portion 71 is provided at the upper end portion of the main shaft portion 70 so that its central axis is eccentric with respect to the central axis of the main shaft portion 70 . The eccentric shaft portion 71 is connected to the orbiting scroll 5 through a slider 80 of a bushing 8 (to be described later), which is a metal member such as iron, and is rotatably supported by a boss portion 51 of the orbiting scroll 5 . The rotating shaft 7 rotates with the rotation of the rotor 6b, and the eccentric shaft portion 71 causes the orbiting scroll 5 to perform a revolving motion, which is an oscillating motion. Further, inside the main shaft portion 70 and the eccentric shaft portion 71, an oil passage hole 72 is provided so as to penetrate vertically along the axial direction.

The bushing 8 includes a slider 80 and a balance weight 81, as shown in FIGS. The slider 80 is a tubular member having a flange, and is rotatably inserted into the boss portion 51 . An eccentric shaft portion 71 is inserted inside the slider 80 . That is, the slider 80 is inserted between the orbiting scroll 5 and the eccentric shaft portion 71 . The slider 80 allows the swing radius of the swing scroll 5 to be variable and supports the swing scroll 5 to revolve.

The balance weight 81 is provided to offset the centrifugal force of the orbiting scroll 5 generated by the revolution orbiting motion. The balance weight 81 has an annular shape and has a substantially C-shaped weight portion 81 a on the side opposite to the direction of the centrifugal force acting on the orbiting scroll 5 . In the scroll compressor 100, the balance weight 81 can reduce the pressure of the second spiral protrusion 5b against the first spiral protrusion 4b. The balance weight 81 is fixed to the collar of the slider 80 by shrink fitting or the like, for example.

The subframe 9 is a metal frame. The sub-frame 9 is provided with a sub-bearing portion 90 and an oil pump 91 as shown in FIG. The sub-bearing portion 90 is a ball bearing provided in the center of the sub-frame 9 . The oil pump 91 is a pump for sucking up lubricating oil stored in the oil sump 18 of the shell 1 and is provided below the sub-bearing portion 90 .

The lubricating oil is stored in the oil reservoir 18 as shown in FIG. The lubricating oil is sucked up by the oil pump 91, passes through the oil passage hole 72 of the rotating shaft 7, and is used to reduce wear between mechanically contacting parts such as the compression mechanism 3, adjust the temperature of the sliding parts, and improve sealing performance. make improvements. As the lubricating oil, an oil that has excellent lubricating properties, electrical insulation properties, stability, refrigerant solubility, low-temperature fluidity, etc., and an appropriate viscosity is suitable. Lubricating oils can be, for example, naphthenic, polyol ester (POE), polyvinyl ether (PVE) or polyalkylene glycol (PAG) oils.

Next, the operation of the scroll compressor 100 will be described. When the power supply terminal 19b of the power supply unit 19 is energized, torque is generated between the stator 6a and the rotor 6b, and the rotary shaft 7 rotates accordingly. Rotation of the rotating shaft 7 is transmitted to the orbiting scroll 5 via the eccentric shaft portion 71 and the bushing 8 . The orbiting scroll 5 , to which the rotational driving force is transmitted, is restrained from rotating by the Oldham ring 54 and performs eccentric orbital motion with respect to the fixed scroll 4 . At that time, the other surface of the orbiting scroll 5 slides on the thrust plate 25 .

As the orbiting scroll 5 swings, the refrigerant sucked into the shell 1 from the suction pipe 13 is taken into the compression chamber 30 . The flow of the refrigerant from each of the main branch pipe 13a and the sub-branch pipe 13b that constitute the suction pipe 13 will be explained again. The refrigerant taken into the compression chamber 30 is reduced in volume and compressed while moving from the outside to the inside in the radial direction of the scroll as the orbiting scroll 5 eccentrically revolves. During the eccentric orbital operation of the orbiting scroll 5, the orbiting scroll 5 moves in the radial direction together with the bush 8 due to its own centrifugal force, and the side wall surfaces of the second spiral projection 5b and the first spiral projection 4b come into close contact with each other. . The compressed refrigerant flows from the discharge port 40 of the fixed scroll 4 to the discharge hole 15 a of the discharge chamber 15 and is discharged outside the shell 1 against the discharge valve 17 .

The refrigerant discharged from the scroll compressor 100 is separated into refrigerant and oil by an oil separator in the refrigerant circuit. The refrigerant circulates through the refrigerant circuit as it is and is sucked into the scroll compressor 100 again. The separated oil does not circulate in the refrigerant circuit and is returned to a pipe 133 (described later) of the scroll compressor 100 (see FIG. 4 described later).

By the way, in order to reduce the suction pressure loss in the conventional scroll compressor, it is necessary to expand the suction port provided in the frame radially inwardly of the rotating shaft. The plate must be made small, and a large capacity cannot be achieved.

On the other hand, in the scroll compressor 100 of Embodiment 1, in addition to the main branch pipe 13a, the sub-branch pipe 13b communicating with the refrigerant intake space 37 is connected to the shell 1, so that the suction pressure loss It is possible to achieve both a reduction in power consumption and an increase in capacity. This point will be described below.

FIG. 4 is a diagram showing a refrigerant intake path of the scroll compressor according to Embodiment 1. FIG. An inlet end 132a of a three-pronged pipe 132 is connected to an outlet end 133a of the pipe 133 constituting the refrigerant circuit on the side of the scroll compressor 100 by, for example, brazing. The suction pipe 13 is connected to two outlet ends 132b and 132c of the three-pronged pipe 132 via connecting

pipes

131a and 131b. Specifically, the main branch pipe 13a is connected to the outlet end 132b of the three-pronged pipe 132 via a connecting pipe 131a, and the sub-branch pipe 13b is connected to the outlet end 132c of the three-pronged pipe 132 via a connecting pipe 131b. It is connected. The main branch pipe 13a and the sub-branch pipe 13b are connected to the three-way pipe 132 by brazing or the like.

Refrigerant sucked into the scroll compressor 100 from the refrigerant circuit passes through a pipe 133 and is branched into two paths by a three-way pipe 132, and is sucked into the shell 1 from each of the main branch pipe 13a and the sub-branch pipe 13b. . The pipe 133 may be a straight pipe or a curved pipe depending on the orientation of the downstream end of the pipe of the refrigerant circuit to which the pipe 133 is connected. Specifically, when the downstream end of the pipe of the refrigerant circuit faces downward and is positioned above the inlet end 132a of the three-pronged pipe 132, the pipe 133 becomes a straight pipe as indicated by the solid line in FIG. On the other hand, when the downstream end of the pipe of the refrigerant circuit is oriented horizontally, the pipe 133 becomes a curved pipe as indicated by the dotted line in FIG.

The refrigerant sucked into the low-pressure space 16b inside the shell from the main branch pipe 13a cools the stator 6a and the rotor 6b, which are the parts of the electric motor, and is drawn into the refrigerant intake space 37 through the intake port 26 of the frame 2. After that, it is taken into the compression chamber 30 . Refrigerant sucked into the shell from the other sub-branch pipe 13 b is taken directly into the refrigerant take-in space 37 without going through the suction port 26 and then taken into the compression chamber 30 . Here, the refrigerant that has entered the low-pressure space 16b inside the shell from the main branch pipe 13a passes through the suction port 26 before being taken into the compression chamber 30, thereby causing suction pressure loss. On the other hand, the refrigerant sucked into the shell from the sub-branch pipe 13b is directly taken into the refrigerant take-in space 37 without going through the suction port 26, and then taken into the compression chamber 30, thereby reducing the suction pressure loss. can.

As described above, the scroll compressor 100 takes part of the refrigerant sucked into the shell 1 from the suction pipe 13 directly into the refrigerant intake space 37 from the sub-branch pipe 13b. As a result, the scroll compressor 100 can reduce the suction pressure loss compared to the case where all the refrigerant sucked into the shell 1 is taken into the refrigerant take-in space 37 via the main branch pipe 13 a and the suction port 26 . Therefore, the scroll compressor 100 cools the motor parts by the refrigerant sucked into the low-pressure space 16b from the main branch pipe 13a as in the conventional art, while increasing the suction pressure without extending the opening of the suction port 26 radially inward. Loss can be reduced.

In this way, the scroll compressor 100 can reduce the suction pressure loss without enlarging the suction port 26, and as a result, it is not necessary to reduce the size of the rocking bed plate 5a. Therefore, the scroll compressor 100 can expand the capacity of the compression chamber 30 . That is, the scroll compressor 100 can achieve both a reduction in suction pressure loss and an increase in capacity.

Also, when the scroll compressor 100 rotates at a high speed, the refrigerant containing oil drawn into the low-pressure space 16b from the main branch pipe 13a is drawn up by the rotating rotor 6b and the balancer 12. As a result, the amount of oil taken into the compression chamber 30 together with the refrigerant increases, which tends to increase the oil discharge. However, in the scroll compressor 100, part of the refrigerant from the refrigerant circuit is branched to the sub-branch pipe 13b to reduce the amount of refrigerant sucked from the main branch pipe 13a into the low-pressure space 16b. can be expected to be reduced.

Although the downstream of the pipe 133 is branched into two here, it may be branched into three or more. In a configuration in which the downstream of the pipe 133 branches into three or more, some of the plurality of branch pipes are connected to the shell 1 so as to communicate with the refrigerant intake space 37, and the rest of the plurality of branch pipes is connected to the shell 1 so as to communicate with the low-pressure space 16b.

As described above, the scroll compressor 100 of the first embodiment includes the shell 1, the suction pipe 13 for sucking the refrigerant into the shell 1, and the fixed base plate 4a provided with the first spiral protrusion 4b. and a rocking bed plate 5a provided with a second spiral protrusion 5b that meshes with the first spiral protrusion 4b. A swing scroll 5 is provided. The scroll compressor 100 further includes an electric motor 6 that drives the orbiting scroll 5, and a frame that is fixed to the inner wall surface of the shell 1 and supports the orbiting scroll 5 on the opposite side of the orbiting scroll 5 from the compression chamber 30. 2 and a. The scroll compressor 100 passes the refrigerant sucked into the shell 1 from the suction pipe 13 through the suction port 26 formed in the frame 2 to the outer peripheral side of the first spiral projection 4b and the second spiral projection 5b. After being taken into the refrigerant take-in space 37, it is taken into the compression chamber 30 and compressed. The intake pipe 13 has a plurality of branch pipes, and each of the plurality of branch pipes is connected to the shell 1 so as to communicate with the inside of the shell 1 . A sub-branch pipe 13 b that is a part of the plurality of branch pipes communicates with the refrigerant intake space 37 .

With the above configuration, the scroll compressor 100 can achieve both a reduction in suction pressure loss and an increase in capacity.

Also, the electric motor 6 is arranged in a space on the opposite side of the frame 2 to the orbiting scroll 5 inside the shell 1, and in that space is the main branch pipe which is the remaining branch pipe of the plurality of branch pipes. The branch pipe 13a is in communication.

With the above configuration, the scroll compressor 100 can cool the parts that make up the electric motor 6 with the refrigerant sucked into the shell 1 from the main branch pipe 13a.

Further, the scroll compressor 100 satisfies the relationship of pipe diameter of the main branch pipe 13a>pipe diameter of the sub-branch pipe 13b.

With the above configuration, the scroll compressor 100 can suck refrigerant mainly from the main branch pipe 13a.

Also, the main branch pipe 13a and the sub-branch pipe 13b are connected to a side surface of the shell 1 facing the intake port 26 across the rotation shaft 7 when viewed in the axial direction of the rotation shaft 7 of the electric motor 6 .

With the above configuration, the scroll compressor 100 can balance the refrigerant intake amount from each refrigerant intake port to each compression chamber 30 .

Embodiment 2.
Embodiment 2 is a configuration in which scroll compressor 100 according to Embodiment 1 is further provided with flow rate control valve 134 . Other configurations are the same as or equivalent to those of the first embodiment. Hereinafter, the second embodiment will be described with a focus on the configuration different from the first embodiment, and the configurations not described in the second embodiment are the same as those in the first embodiment.

FIG. 5 is a diagram showing a refrigerant intake path of a scroll compressor according to Embodiment 2. FIG. Embodiment 2 differs from Embodiment 1 in that it further includes a flow control valve 134 that regulates the flow rate of refrigerant in sub-branch pipe 13b. The flow regulating valve 134 is composed of, for example, an electronic expansion valve. The flow control valve 134 is provided on the pipe 1310b. The pipe 1310b has a connection port 13ba (see FIG. 3) with the shell 1 of the sub-branch pipe 13b, and a branch port that is upstream of the connection port 13ba and branches the refrigerant from the refrigerant circuit toward the sub-branch pipe 13b. 132d and a pipe connecting the . The branch port 132 d is located inside the three-way pipe 132 .

The pipe 1310b specifically includes a sub-branch pipe 13b, a connecting pipe 131b, and a pipe portion downstream of the branch port 132d in the three-pronged pipe 132. Although FIG. 5 shows a configuration in which the flow rate adjustment valve 134 is provided in the connecting pipe 131b, it may be provided in the sub-branch pipe 13b, or in the three-pronged pipe 132, a pipe portion downstream of the branch port 132d. may be provided in In short, the flow regulating valve 134 may be provided in the pipe 1310b connecting the connection port 13ba and the branch port 132d as described above.

The flow control valve 134 is controlled by a control device (not shown). Control of the flow regulating valve 134 is divided into the following two types depending on the purpose.

(1) Purpose of Cooling Electric Motor 6 When the scroll compressor 100 rotates at a low speed, the amount of refrigerant circulating in the refrigerant circuit decreases, so the amount of refrigerant sucked into the shell 1 decreases. As the amount of refrigerant drawn into the shell 1 decreases, if a portion of the refrigerant is drawn into the shell 1 through the sub-branch pipe 13b, the amount of refrigerant flowing into the low-pressure space 16b from the main branch pipe 13a is reduced. It becomes impossible to sufficiently cool the electric motor parts. In other words, there is a possibility of insufficient cooling of the motor components at low rotational speeds.

Therefore, when the flow control valve 134 is controlled for the purpose of cooling the electric motor 6, the flow control valve 134 is closed when the rotation speed of the electric motor 6 is lower than the preset first rotation speed. When the flow control valve 134 is closed, the scroll compressor 100 sucks all the refrigerant from the refrigerant circuit into the low-pressure space 16b from the main branch pipe 13a without branching, and uses it for cooling the motor parts. As a result, the scroll compressor 100 can suppress insufficient cooling of the electric motor parts at low rotational speeds, and can sufficiently cool the electric motor parts.

(2) The purpose of adjusting the amount of oil in the scroll compressor 100 so that the amount of oil in the scroll compressor 100 does not decrease When the rotation speed of the electric motor 6 increases from low rotation speed to high rotation speed, the amount of refrigerant circulating in the refrigerant circuit increases. Refrigerant sucked into the inside of 1 also increases. As the amount of refrigerant sucked into the shell 1 increases, the amount of oil that rises due to hoisting increases. Therefore, when the number of revolutions of the electric motor 6 increases from the low number of revolutions to the high number of revolutions, the opening degree of the flow control valve 134 is gradually increased. Specifically, when the rotation speed increases to a rotation speed higher than the preset second rotation speed, the opening degree of the flow control valve 134 is gradually increased. It should be noted that "gradually" includes stepwise, linear and quadratic forms. Here, linearly functional refers to a mode in which the amount of increase in the degree of opening is constant from the start to the end of change in the degree of opening. The quadratic function refers to a form in which the amount of increase in the opening degree increases from the start to the end of the change in the opening degree.

In this way, as the rotational speed of the electric motor 6 increases, the degree of opening of the flow control valve 134 is gradually increased, so that the amount of refrigerant sucked into the refrigerant intake space 37 from the sub-branch pipe 13b gradually increases. . As a result, the amount of refrigerant sucked from the main branch pipe 13a into the low-pressure space 16b is gradually reduced, and the scroll compressor 100 can suppress oil rise. As a result, the scroll compressor 100 can suppress a decrease in the amount of oil inside.

Although the flow control valve 134 is controlled based on the rotation speed of the electric motor 6, it may be controlled based on the suction pressure of the refrigerant. Specifically, when the suction pressure increases, the flow rate of the refrigerant increases and more oil is swirled up. , the degree of opening is gradually increased. Further, the flow control valve 134 may be controlled based on both the rotation speed of the electric motor 6 and the suction pressure of the refrigerant. In other words, the flow control valve 134 is controlled based on one or both of the rotational speed of the electric motor 6 and the suction pressure of the refrigerant.

The scroll compressor 100 of Embodiment 2 can obtain the same effect as that of Embodiment 1, and the flow control valve 134 is provided in the pipe 1310b between the connection port 13ba and the branch port 132d. effect is obtained. That is, the scroll compressor 100 is controlled by the flow control valve 134 to suppress insufficient cooling of the motor parts at low rotational speeds and reduce the oil inside the scroll compressor 100 when the rotational speed is increased from low to high. It is possible to suppress the reduction of the amount.

Embodiment 3.
The third embodiment relates to a refrigeration cycle apparatus including the scroll compressor 100 of the second embodiment.

6 is a diagram showing a refrigerant circuit of a refrigeration cycle apparatus according to Embodiment 3. FIG.
Refrigeration cycle device 105 includes scroll compressor 100 of Embodiment 2, condenser 101, expansion valve 102 as a decompression device, and evaporator 103, and includes refrigerant circuit 104 in which refrigerant circulates. there is The gas refrigerant discharged from the scroll compressor 100 flows into the condenser 101, exchanges heat with the air passing through the condenser 101, and flows out as a high-pressure liquid refrigerant. The high-pressure liquid refrigerant that has flowed out of the condenser 101 is decompressed by the expansion valve 102 to become a low-pressure gas-liquid two-phase refrigerant and flows into the evaporator 103 . The low-pressure gas-liquid two-phase refrigerant that has flowed into the evaporator 103 exchanges heat with the air passing through the evaporator 103 to become a low-pressure gas refrigerant, and is supplied to the scroll compressor 100 again via the main branch pipe 13a and the sub-branch pipe 13b. inhaled.

The refrigeration cycle device 105 further includes a control device 106 that controls the refrigerant circuit 104 . The control device 106 is composed of a microprocessor unit and includes a CPU, RAM, ROM, etc. Control programs and the like are stored in the ROM. Controller 106 is not limited to a microprocessor unit. For example, controller 106 may be configured with something that can be updated, such as firmware. Also, the control device 106 may be a program module that is executed by a command from a CPU (not shown) or the like.

When the refrigeration cycle device 105 is an air conditioner that air-conditions the room, the control device 106 controls the rotation speed of the electric motor 6 according to the temperature difference between the room temperature and the set temperature. Specifically, the control device 106 performs control to increase the rotational speed of the electric motor 6 as the temperature difference increases, in other words, as the load on the scroll compressor 100 increases. Further, as described in the second embodiment, the control device 106 performs control to close the flow control valve 134 when the rotational speed of the electric motor 6 is lower than the preset first rotational speed. Further, the control device 106 performs control to gradually increase the opening degree of the flow control valve 134 when increasing the rotational speed of the electric motor 6 above the preset second rotational speed.

With the above-described control, the refrigeration cycle device 105 can sufficiently cool the electric motor parts as described above, and can suppress a decrease in the amount of oil inside the scroll compressor 100, thereby improving the reliability of the scroll compressor 100. can improve sexuality.

Here, the configuration in which the refrigeration cycle device 105 includes the scroll compressor 100 of the second embodiment is shown, but it may be configured to include the scroll compressor 100 of the first embodiment. Refrigerating cycle device 105 is included in scroll compressor 100 of the first or second embodiment, so that both reduction in suction pressure loss and increase in capacity can be achieved. Moreover, the refrigeration cycle device 105 including the scroll compressor 100 of Embodiment 2 can further improve the reliability of the scroll compressor 100 .

1 shell, 1a main shell, 1b upper shell, 1c lower shell, 1d fixed base, 2 frame, 3 compression mechanism, 4 fixed scroll, 4a fixed base plate, 4b first spiral projection, 5 oscillating scroll, 5a oscillating base plate, 5b second spiral projection, 6 electric motor, 6a stator, 6b rotor, 7 rotating shaft, 8 bushing, 9 subframe, 10a first inner wall surface, 10b second inner wall surface, 10c third inner wall surface, 11a third 1 step portion, 11b second step portion, 12 balancer, 13 suction pipe, 13a main branch pipe, 13b sub-branch pipe, 13ba connection port, 14 discharge pipe, 15 discharge chamber, 15a discharge hole, 16a high pressure space, 16b low pressure space , 17 discharge valve, 18 oil sump, 19 power supply part, 19a cover, 19b power supply terminal, 19c wiring, 20 flat surface, 21 accommodation part, 21a Oldham accommodation part, 21b bush accommodation part, 21c first Oldham groove, 22 main bearing part, 23 oil return hole, 24 oil return pipe, 25 thrust plate, 26 suction port, 30 compression chamber, 37 refrigerant intake space, 40 discharge port, 41 tip seal, 51 boss, 52 tip seal, 53 second Oldham groove , 54 Oldham ring, 54a ring portion, 54b first key portion, 54c second key portion, 70 main shaft portion, 71 eccentric shaft portion, 72 oil passage hole, 80 slider, 81 balance weight, 81a weight portion, 90 auxiliary bearing portion , 91 oil pump, 100 scroll compressor, 101 condenser, 102 expansion valve, 103 evaporator, 104 refrigerant circuit, 105 refrigeration cycle device, 106 control device, 131a connecting pipe, 131b connecting pipe, 132 three-pronged pipe, 132a inlet End, 132b outlet end, 132c outlet end, 132d branch port, 133 pipe, 133a outlet end, 134 flow control valve, 1310b pipe.

Claims

A shell, a suction pipe for sucking refrigerant into the shell, a fixed scroll having a fixed base plate provided with a first spiral projection, and a second spiral projection meshing with the first spiral projection are provided. an oscillating scroll forming a compression chamber for compressing a refrigerant between itself and the fixed scroll; an electric motor for driving the oscillating scroll; a frame supporting the orbiting scroll on a side opposite to the compression chamber with respect to the orbiting scroll, the refrigerant sucked into the shell from the suction pipe being introduced into an intake port formed in the frame; A scroll compressor in which refrigerant is taken into a refrigerant intake space on the outer peripheral side of the first spiral protrusion and the second spiral protrusion via a refrigerant intake space, and then taken into the compression chamber and compressed,
The suction pipe has a plurality of branch pipes, each of the plurality of branch pipes is connected to the shell so as to communicate with the inside of the shell, and some of the plurality of branch pipes are branch pipes. is in communication with the refrigerant intake space.
The electric motor is arranged in a space inside the shell on the opposite side of the frame from the orbiting scroll, and the remaining branch pipes of the plurality of branch pipes communicate with the space. A scroll compressor according to claim 1.
connecting a connection port of the part of the branch pipe with the shell, and a branch port upstream of the connection port that branches the refrigerant from the refrigerant circuit toward the part of the branch pipe; 3. The scroll compressor according to claim 1, wherein a flow control valve is provided in the piping including said part of the branch pipes.
The scroll compressor according to any one of claims 1 to 3, which satisfies the relationship of the diameter of the remaining branch pipe among the plurality of branch pipes>the diameter of the part of the branch pipes.
5. The plurality of branch pipes are connected to a side surface of the shell facing the intake port across the rotation shaft when viewed in the axial direction of the rotation shaft of the electric motor. or the scroll compressor according to claim 1.
The scroll compressor according to any one of claims 1 to 5, wherein the fixed scroll is fixed to the inner wall surface of the shell.
A refrigeration cycle apparatus comprising the scroll compressor according to any one of claims 1 to 6, a condenser, a decompression device, and an evaporator, and comprising a refrigerant circuit in which refrigerant circulates.
A control device that controls the refrigerant circuit,
8. The refrigeration cycle apparatus according to claim 7, wherein said control device controls said flow control valve based on one or both of the number of revolutions of said electric motor and the suction pressure of said refrigerant.
A control device that controls the refrigerant circuit,
The control device performs control to increase the rotation speed of the electric motor as the load on the scroll compressor increases, and when the rotation speed of the electric motor is lower than a preset first rotation speed, 8. The refrigeration cycle apparatus according to claim 7, wherein said flow control valve is closed.
A control device that controls the refrigerant circuit,
The control device performs control to increase the rotation speed of the electric motor as the load on the scroll compressor increases. 8. The refrigeration cycle apparatus according to claim 7, wherein the opening degree of said flow control valve is gradually increased.