WO2018139314A1

WO2018139314A1 - Refrigeration device

Info

Publication number: WO2018139314A1
Application number: PCT/JP2018/001218
Authority: WO
Inventors: 熊倉　英二; 古庄　和宏
Original assignee: ダイキン工業株式会社
Priority date: 2017-01-30
Filing date: 2018-01-17
Publication date: 2018-08-02
Also published as: JP2018123974A

Abstract

A refrigerant in a refrigerant circuit (11) includes a hydrofluorocarbon having the characteristic of causing disproportionation reactions. A compressor mechanism (40) has provided therein: a blade (51) integrally coupled to pistons (44, 44a, 44b, 77) and partitioning cylinder chambers (45, 45a, 45b, 81, and 82) into a low pressure chamber (L) and a high pressure chamber (H); and a pair of bushes (52) that are pivotably held in a pair of bush grooves (53) formed in cylinders (2, 42a, 42b, 75) and hold the blade (51) so as to be capable of moving forward and backwards.

Description

Refrigeration equipment

The present invention relates to a refrigeration apparatus including a compressor.

Conventionally, a refrigeration apparatus having a refrigerant circuit connected to a compressor and performing a refrigeration cycle is known and widely used in air conditioners and the like.

As a compressor connected to a refrigeration circuit, Patent Document 1 discloses a rotary compressor. In this compressor, as shown in FIG. 13, an annular piston 103 is arranged in a cylinder chamber 102 inside a cylinder 101. The piston 103 is fitted in a crankshaft 104 that is rotationally driven by an electric motor. The cylinder 101 is formed with a vane groove 106 that accommodates the vertically long vane 105. The vane 105 is urged toward the piston 103 by a spring (not shown), for example, and the tip of the vane 105 is always in sliding contact with the outer peripheral surface of the piston 103. The vane 105 divides the cylinder chamber 102 into a low pressure chamber 108 that communicates with the suction port 107 and a high pressure chamber 109 that communicates with a discharge port (not shown). When the piston 103 rotates eccentrically in the cylinder chamber 102, the refrigerant sucked into the low pressure chamber 108 is compressed in the high pressure chamber 109 and discharged from the discharge port.

Japanese Patent Laying-Open No. 2015-169089

By the way, when the refrigerant | coolant applied to the compressor mentioned above has the property which raise | generates disproportionation reaction, there existed a possibility that this refrigerant | coolant might raise | generate disproportionation reaction inside a compression mechanism. Here, the disproportionation reaction is a chemical reaction in which the same kind of molecules react with each other to give different products.

Specifically, in the rotary compressor described above, as shown in FIG. 13, the tip of the vane is always pressed against the outer peripheral surface of the piston so as to partition the low pressure chamber and the high pressure chamber. For this reason, the temperature of the sliding portion at the tip of the vane (for example, the portion indicated by point a in FIG. 13) may increase, and the temperature of the refrigerant in the vicinity may increase.

Also, the vane is pressed in the direction of the white arrow in FIG. 13 due to the differential pressure between the low pressure chamber and the high pressure chamber. For this reason, since the vane is inclined with respect to the advancing / retreating direction, a contact portion (for example, a portion indicated by point b in FIG. 13) between the side surface of the vane and the edge of the insertion opening of the vane groove, or the rear end of the vane. One-side contact occurs at the contact portion between the corner portion and the inner wall of the vane groove (the portion indicated by point c in FIG. 13). As a result, there is a possibility that the temperature of these contact portions increases and the temperature of the refrigerant in the vicinity thereof increases.

Due to such local temperature increase, if the refrigerant temperature becomes higher than a predetermined temperature (temperature at which disproportionation reaction occurs), this refrigerant may cause disproportionation reaction. It was.

The present invention has been made paying attention to such a problem, and its purpose is to prevent the refrigerant from causing a disproportionation reaction inside the compression mechanism.

1st invention is a refrigeration apparatus provided with the refrigerant circuit (11) to which the compressor (30) which compresses a refrigerant | coolant is connected, Comprising: The said refrigerant | coolant has the property which raise | generates a disproportionation reaction The compressor (30) includes an electric motor (32) and a compression mechanism (40) driven by the electric motor (32), and the compression mechanism (40) includes a cylinder chamber (45 , 45a, 45b, 81, 82) formed with a cylinder (42, 42a, 42b, 75) and a piston (44, 44a, 44b) accommodated in the cylinder chamber (45, 45a, 45b, 81, 82) , 77) and the piston (44, 44a, 44b, 77) are integrally connected, and the cylinder chamber (45, 45a, 45b, 81, 82) is connected to the low pressure chamber (L) and the high pressure chamber (H). A pair of blades (51) for partitioning and a pair of bush grooves (53) formed in the cylinders (42, 42a, 42b, 75) so as to be able to swing and hold the blades (51) so as to be able to advance and retract. With bush (52) The piston (44, 44a, 44b, 77) and the cylinder (42, 42a, 42b, 75) are configured to be relatively eccentrically rotated.

In the first invention, the blade (51) that divides the cylinder chamber (45, 45a, 45b, 81, 82) into the low pressure chamber (L) and the high pressure chamber (H) includes the piston (44, 44a, 44b, 77). It is connected integrally with. For this reason, there is no sliding contact portion between the tip of the vane and the piston as in the rotary compressor. Therefore, it is possible to reliably avoid an increase in the temperature of the refrigerant at the tip of the blade (51).

Since the differential pressure between the low pressure chamber (L) and the high pressure chamber (H) acts on the blade (51), the blade (51) tends to tilt with respect to the advancing / retreating direction of the blade (51). However, even if the blade (51) is tilted, the pair of bushes (52) holding the blade (51) swings inside the bush groove (53). That is, the pair of bushes (52) tilts integrally with the blade (51). For this reason, it can also avoid that a braid | blade (51) and a bush (52) contact locally. Accordingly, unlike the rotary compressor, the temperature of the refrigerant does not increase due to the contact of the vanes.

As described above, in the case of the conventional compressor, the temperature of the refrigerant may be extremely high in the portions corresponding to the points a, b, and c in FIG. Then, the temperature of the refrigerant does not become extremely high. Therefore, even when a fluorinated hydrocarbon having the property of causing a disproportionation reaction is used as the refrigerant of the refrigeration apparatus, the disproportionation reaction can be prevented from occurring inside the compression mechanism.

In a second aspect based on the first aspect, the compression mechanism (40) includes the cylinder (42a, 42b), the piston (44a, 44b), the blade (51), and the bush (52), respectively. It has a plurality of compression sections (61, 62), and is configured to compress the refrigerant in parallel by the plurality of compression sections (61, 62).

In the second invention, since the refrigerant is compressed in parallel by the plurality of compression sections (61.62), the rotational speed of the drive shaft can be reduced as compared with the case where the refrigerant is compressed by only one compression section. As a result, in the compression mechanism, heat generation at the sliding part between the piston and cylinder and the sliding part between the bush and blade can be reduced, and the temperature rise of the refrigerant at each compression part (61, 62) is suppressed. it can.

In a third aspect based on the first aspect, the compression mechanism (40) includes the cylinder (42a, 42b), the piston (44a, 44b), the blade (51), and the bush (52), respectively. A plurality of compression sections (61, 62), and the plurality of compression sections (61, 62) are connected in series.

In the third invention, the refrigerant is compressed in multiple stages in the plurality of compression sections (61, 62). For this reason, compared with the case where a refrigerant | coolant is compressed with one compression part, the differential pressure | voltage (difference of suction pressure and discharge pressure) of the refrigerant | coolant in each compression part (61,62) becomes small. If it does in this way, in each compression part (61,62), since the differential pressure | voltage of a low pressure chamber (L) and a high pressure chamber (H) becomes small, the sliding resistance resulting from a differential pressure | voltage can be reduced. As a result, it is possible to suppress the temperature rise of the refrigerant in each compression section (61, 62).

According to a fourth invention, in any one of the first to third inventions, the compression mechanism (40) includes the cylinder (42) having a non-circular inner peripheral surface and a non-circular outer peripheral surface. And a non-circular piston type in which the piston (44) rotates eccentrically.

In the fourth invention, the compression mechanism (40) is configured as a so-called non-circular piston type. In the non-circular piston type, the volume change rate during one rotation of the compression chamber (high pressure chamber (H)) can be optimized according to the outer peripheral surface shape of the piston (44). Thereby, in the non-circular piston type compression mechanism (40), the timing of the discharge stroke can be advanced, and the period of the discharge stroke can be lengthened. In this way, since over-compression in the discharge stroke can be suppressed, the high-low differential pressure (pressure difference between the high-pressure chamber (H) and the low-pressure chamber (L)) associated with over-compression is reduced. The sliding resistance in the compression mechanism (40) due to the pressure can be further reduced. As a result, a local temperature rise at the sliding portion due to overcompression can be avoided, and the refrigerant can be more effectively suppressed from causing a disproportionation reaction.

The fifth invention is characterized in that, in any one of the first to fourth inventions, the refrigerant is a refrigerant containing HFO-1123.

In the fifth invention, a refrigerant containing HFO-1123 is used as the refrigerant. Since HFO-1123 is easily decomposed by OH radicals in the atmosphere, it has little influence on the ozone layer or global warming. Further, by using a refrigerant containing HFO-1123, the performance of the refrigeration cycle of the refrigeration apparatus is also improved.

According to the present invention, a local temperature rise inside the compression mechanism can be suppressed as in a rotary compressor, so that a refrigeration cycle can be performed while preventing a disproportionation reaction of the refrigerant.

FIG. 1 is a schematic configuration diagram of a refrigeration apparatus according to an embodiment. FIG. 2 is a longitudinal sectional view of the compressor according to the embodiment. FIG. 3 is a cross-sectional view showing the inside of the compression mechanism according to the embodiment. 4A and 4B are cross-sectional views showing the inside of the compression mechanism according to the embodiment. FIG. 4A shows a state where the rotation angle is 0 ° (360 °), and FIG. 4B shows a rotation angle of 90 °. 4C shows a state where the rotation angle is 180 °, and FIG. 4D shows a state where the rotation angle is 270 °. FIG. 5 is an enlarged longitudinal sectional view of a main part of the compressor according to the first modification. FIG. 6 is an enlarged longitudinal sectional view of a main part of the compressor according to the second modification. FIG. 7 is a cross-sectional view showing the inside of the compression mechanism according to the third modification. FIG. 8 is a graph showing the relationship between the compression chamber volume and the rotation angle in the compression mechanism (non-circular piston type) according to Modification 3 and the comparative example (circular piston type). FIG. 9 is an enlarged longitudinal sectional view of a main part of a compressor according to the fourth modification. FIG. 10 is a cross-sectional view showing the inside of the compression mechanism according to the fourth modification. FIG. 11 is an enlarged vertical cross-sectional view of a main part of a compressor according to the fifth modification. FIG. 12 is a cross-sectional view showing the inside of the compression mechanism according to the fifth modification. FIG. 13 is a cross-sectional view showing the inside of a conventional compression mechanism.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its application, or its use.

<Overall configuration of refrigeration equipment>
The refrigeration apparatus according to the embodiment is an air conditioner (10) that performs indoor cooling and heating. As shown in FIG. 1, the air conditioner (10) includes a refrigerant circuit (11) filled with a refrigerant. In the refrigerant circuit (11), the refrigerant circulates to perform a vapor compression refrigeration cycle. As this refrigerant, a refrigerant containing a fluorinated hydrocarbon having a property of causing a disproportionation reaction is used (details will be described later).

The air conditioner (10) includes an outdoor unit (12) and an indoor unit (13). There may be two or more indoor units (13) instead of one.

The refrigerant circuit (11) includes a compressor (30), an outdoor heat exchanger (16) (heat source heat exchanger), an expansion valve (17), and an indoor heat exchanger (18) (utilizing heat exchanger). And a four-way selector valve (19). The compressor (30), the outdoor heat exchanger (16), and the four-way switching valve (19) are accommodated in the outdoor unit (12). The indoor heat exchanger (18) and the expansion valve (17) are accommodated in the indoor unit (13).

In the outdoor unit (12), an outdoor fan (20) is installed in the vicinity of the outdoor heat exchanger (16). In the outdoor heat exchanger (16), the outdoor air conveyed by the outdoor fan (20) and the refrigerant exchange heat. In the indoor unit (13), an indoor fan (21) is installed in the vicinity of the indoor heat exchanger (18). In the indoor heat exchanger (18), the indoor air conveyed by the indoor fan (21) and the refrigerant exchange heat.

The four-way selector valve (19) has first to fourth ports (P1 to P4). The first port (P1) is connected to the discharge pipe (22) of the compressor (30), the second port (P2) is connected to the suction pipe (23) of the compressor (30), and the third port (P3) is outdoor. It connects with the gas end of the heat exchanger (16), and the fourth port (P4) connects with the gas end of the indoor heat exchanger (18). The four-way selector valve (19) switches between a first state (state indicated by a solid line in FIG. 1) and a second state (state indicated by a broken line in FIG. 1). In the first state, the first port (P1) and the fourth port (P4) communicate with each other, and the second port (P2) and the third port (P3) communicate with each other. Therefore, when the compressor (30) is operated when the four-way selector valve (19) is in the first state, the indoor heat exchanger (18) becomes a condenser (heat radiator), and the outdoor heat exchanger (16) A refrigeration cycle (heating cycle) serving as an evaporator is performed. In the second state, the first port (P1) and the third port (P3) communicate with each other, and the second port (P2) and the fourth port (P4) communicate with each other. Therefore, when the compressor (30) is operated when the four-way switching valve (19) is in the second state, the outdoor heat exchanger (16) becomes a condenser (radiator) and the indoor heat exchanger (18) A refrigeration cycle (cooling cycle) serving as an evaporator is performed.

<Overall configuration of compressor>
As shown in FIG. 2, the compressor (30) includes a vertically long cylindrical sealed casing (31). A suction pipe (23) is fixed through the lower portion of the casing (31). A discharge pipe (22) passes through and is fixed to the top (upper end plate) of the casing (31). Oil (refrigeration machine oil) for lubricating each sliding part of the compressor (30) is stored at the bottom of the casing (31). Inside the casing (31), an internal space (S) filled with the refrigerant (discharged refrigerant or high-pressure refrigerant) discharged from the compression mechanism (40) is formed. That is, the compressor (30) of the present embodiment is configured as a so-called high-pressure dome type in which the internal pressure of the internal space (S) of the casing (31) is substantially equal to the pressure of the high-pressure refrigerant.

In the internal space (S) of the casing (31), an electric motor (32), a drive shaft (35), and a compression mechanism (40) are provided in order from top to bottom.

The electric motor (32) has a stator (33) and a rotor (34). The stator (33) is fixed to the inner peripheral surface of the body portion of the casing (31). The rotor (34) penetrates the interior of the stator (33) in the vertical direction. A drive shaft (35) is fixed inside the shaft center of the rotor (34). When the electric motor (32) is energized, the drive shaft (35) is rotationally driven together with the rotor (34).

The drive shaft (35) is located on the axial center of the trunk of the casing (31). The drive shaft (35) is rotatably supported by each bearing of the compression mechanism (40). The drive shaft (35) has a main shaft (36) coaxial with the electric motor (32), and a crank shaft (37) eccentric from the main shaft (36). The outer diameter of the crankshaft (37) is larger than the outer diameter of the main shaft (36). An oil pump (38) that pumps up oil accumulated at the bottom of the casing (31) is provided below the drive shaft (35). The oil pumped up by the oil pump (38) is supplied to each sliding portion of the bearing and the compression mechanism (40) through a flow path (not shown) inside the drive shaft (35).

The compression mechanism (40) is arranged below the electric motor (32). The compression mechanism (40) has a front head (41), a cylinder (42), a rear head (43), and a piston (44). The cylinder (42) is formed in a flat cylindrical shape. The opening at the upper end of the cylinder (42) is closed by the front head (41), and the opening at the lower end of the cylinder (42) is closed by the rear head (43). Thereby, a cylindrical cylinder chamber (45) is defined inside the cylinder (42).

An annular piston (44) is accommodated in the cylinder chamber (45). The piston (44) is fitted into the crankshaft (37). Therefore, when the drive shaft (35) is rotationally driven by the electric motor (32), the piston (44) rotates eccentrically in the cylinder chamber (45).

In the cylinder (42), a suction port (46) communicating with the cylinder chamber (45) (strictly, the low pressure chamber (L)) penetrates in the radial direction. A suction pipe (23) is connected to the suction port (46). The front head (41) is formed with a discharge port (47) communicating with the cylinder chamber (strictly speaking, the high pressure chamber (H)). The discharge port (47) is provided with a discharge valve (not shown) such as a reed valve.

A muffler (48) covering the front head (41) is attached to the upper part of the compression mechanism (40). A muffler space (49) communicating with the discharge port (47) is formed inside the muffler (48). In the muffler space (49), noise caused by refrigerant discharge pulsation is reduced.

<Internal structure of compression mechanism>
The compression mechanism (40) is configured as a swinging piston type having a blade (51) and a bush (52). As shown in FIGS. 2 and 3, the cylinder (42) is formed with a bush groove (53) and a back pressure chamber (54). The bush groove (53) is formed at a position adjacent to the cylinder chamber (45) and communicates with the cylinder chamber (45). The bush groove (53) forms a cylindrical space having a substantially circular cross section. The back pressure chamber (54) is located radially outward of the bush groove (53) in the cylinder (42). The back pressure chamber (54) forms a columnar space having a substantially circular cross section.

The back pressure chamber (54) has an end on the cylinder chamber (45) side communicating with the bush groove (53). The back pressure chamber (54) is an atmosphere of a high pressure corresponding to the pressure of the internal space (S) of the casing (31) (that is, the pressure of the refrigerant discharged from the compression mechanism (40)). The oil pumped up by the oil pump (38) is supplied to the back pressure chamber (54). The oil in the back pressure chamber (54) is used to lubricate the sliding part between the inner peripheral surface of the bush groove (53) and the bush (52) and the sliding part of the bush (52) and blade (51). Is done.

The pair of bushes (52) has a substantially cross-sectional or semicircular cross section. The pair of bushes (52) is swingably held inside the bush groove (53). The pair of bushes (52) includes an arc portion (52a) facing the bush groove (53) and a flat portion (52b) facing the blade (51). The pair of bushes (52) swings so that the arc portion (52a) is in sliding contact with the bush groove (53) with the center of the bush groove (53) as an axis.

The pair of bushes (52) are arranged in the bush grooves (53) so that the flat portions (52b) face each other. Thereby, a blade groove (55) is formed between the flat portions (52b) of the pair of bushes (52). The blade groove (55) has a substantially rectangular cross section, and the blade (51) is held therein so as to be able to advance and retreat in the radial direction.

The blade (51) is formed in a rectangular parallelepiped shape or a plate shape extending radially outward. The base end (radially inner end) of the blade (51) is integrally connected to the outer peripheral surface of the piston (44). Here, the piston (44) and the blade (51) may be integrally molded with the same member, or another member may be fixed integrally. The tip (radially outer end) of the blade (51) is located in the back pressure chamber (54). The blade (51) partitions the cylinder chamber (45) into a low pressure chamber (L) and a high pressure chamber (H). The low pressure chamber (L) is a space on the right side of the blade (51) in FIG. 2 and communicates with the suction port (46). The high pressure chamber (H) is a space on the left side of the blade (51) in FIG. 2 and communicates with the discharge port (47).

-Compressor operation-
When the electric motor (32) is energized and the drive shaft (35) is driven to rotate, the piston (44) performs an eccentric motion (strictly, a swinging motion) in the cylinder chamber (45).

As shown in FIG. 4, in the compression mechanism (40), the outer peripheral surface of the piston (44) is in line contact with the inner peripheral surface of the cylinder chamber (45) through the oil film to form a seal portion. When the piston (44) swings, the seal portion between the piston (44) and the cylinder (42) is displaced along the inner peripheral surface of the cylinder chamber (45), and the low pressure chamber (L) The volume of the high pressure chamber (H) changes. At this time, the blade (51) advances and retreats in the blade groove (55) according to the rotation angle of the piston (44). At the same time, the pair of bushes (52) swings with the blade (51) about the axis of the bush groove (53). Note that the “rotation angle” here refers to the position where the piston (44) is closest to the bush groove (53) (so-called top dead center) as a reference 0 °, and the direction of rotation of the drive shaft (35) (the timepiece of FIG. 4). The angle is expressed in the direction of rotation).

When the volume of the low pressure chamber (L) gradually increases with the swinging motion of the piston (44), the low pressure refrigerant is sucked into the low pressure chamber (L) through the suction pipe (23) and the suction port (46). . Next, when the low pressure chamber (L) is blocked from the suction port (46), the blocked space constitutes the high pressure chamber (H). Next, as the volume of the high pressure chamber (H) gradually decreases, the internal pressure of the high pressure chamber (H) increases. When the internal pressure of the high pressure chamber (H) becomes larger than the pressure of the internal space (S), the discharge stroke is performed. That is, in the discharge stroke, the discharge valve of the discharge port (47) is opened, and the refrigerant in the high pressure chamber (H) flows out of the compression mechanism (40) through the discharge port (47). The refrigerant discharged from the discharge port (47) flows out to the internal space (S) through the muffler space (49). The refrigerant in the internal space (S) flows around the electric motor (32), then flows out of the discharge pipe (22), and is sent to the refrigerant circuit (11).

-About refrigerant-
The refrigerant charged in the refrigerant circuit (11) includes a single refrigerant composed of a fluorinated hydrocarbon having the property of causing a disproportionation reaction, or a fluorinated hydrocarbon having a property of causing a disproportionation reaction, and the others. A mixed refrigerant comprising at least one kind of refrigerant can be used.

Fluorohydrocarbons having the property of causing a disproportionation reaction include hydrofluoroolefins that have a carbon-carbon double bond that has little impact on the ozone layer and global warming and is easily decomposed by OH radicals ( HFO) can be used. Specifically, as such an HFO refrigerant, it is preferable to use trifluoroethylene (HFO-1123) having excellent performance as described in JP-A-2015-7257 and JP-A-2016-28119. . As HFO refrigerants other than HFO-1123, 3,3,3-trifluoropropene (HFO-1243zf), 1,3,3,3-tetrafluoro described in JP-A No. 04-110388 Propene (HFO-1234ze), 2-fluoropropene (HFO-1261yf), 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,1,2-trifluoropropene (HFO-1243yc), special 1,2,3,3,3-pentafluoropropene (HFO-1225ye), trans-1,3,3,3-tetrafluoropropene (HFO-1234ze (E) described in Table 2006-512426 )), Cis-1,3,3,3-tetrafluoropropene (HFO-1234ze (Z)), As long as it has a property of causing disproportionation reaction it is applicable to the present invention. Further, as the fluorinated hydrocarbon having the property of causing a disproportionation reaction, an acetylene-based fluorinated hydrocarbon having a carbon-carbon triple bond may be used.

In the case of using a mixed refrigerant containing a fluorinated hydrocarbon having the property of causing a disproportionation reaction, it is preferable that the above-mentioned HFO-1123 is included. For example, a mixed refrigerant composed of HFO-1123 and HFC-32 can be used. The composition ratio of the mixed refrigerant is preferably, for example, HFO-1123: HFC-32 = 40: 60 (unit: wt%). A mixed refrigerant composed of HFO-1123, HFC-32, and HFO-1234yf can also be used. The composition ratio of the mixed refrigerant is preferably, for example, HFO-1123: HFC-32: HFO-1234yf = 40: 44: 16 (unit: wt%). Furthermore, AMOLEA X series (registered trademark: manufactured by Asahi Glass Co., Ltd.) and AMOLEA Y series (registered trademark: manufactured by Asahi Glass Co., Ltd.) can also be used as the mixed refrigerant.

Also, as other refrigerants included in the mixed refrigerant, vaporization and liquefaction together with HFO-1123 such as hydrocarbon (HC), hydrofluorocarbon (HFC), hydrochlorofluoroolefin (HCFO), chlorofluoroolefin (CFO), etc. Other materials may be used.

HFC is a component that improves performance and has little impact on the ozone layer and global warming. It is preferable to use HFC having 5 or less carbon atoms. Specifically, as HFC, difluoromethane (HFC-32), difluoroethane (HFC-152a), trifluoroethane (HFC-143), tetrafluoroethane (HFC-134), pentafluoroethane (HFC-125), Pentafluoropropane (HFC-245ca), hexafluoropropane (HFC-236fa), heptafluoropropane (HFC-227ea), pentafluorobutane (HFC-365), heptafluorocyclopentane (HFCP), and the like can be used. Of these, difluoromethane (HFC-32), 1,1-difluoroethane (HFC-152a), 1,1,2,2-tetrafluoroethane are less affected by both the ozone layer and global warming. Particular preference is given to using (HFC-134), 1,1,1,2-tetrafluoroethane (HFC-134a) and pentafluoroethane (HFC-125). These HFCs may be used alone or in combination of two or more.

HCFO is a compound that has a carbon-carbon double bond, has a high proportion of halogen in the molecule, and has reduced combustibility. HCFO includes 1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd), 1-chloro-2,2-difluoroethylene (HCFO-1122), 1,2-dichlorofluoroethylene (HCFO). -1121), 1-chloro-2-fluoroethylene (HCFO-1131), 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd) can be used. Among them, HCFO-1224yd having particularly excellent performance is preferable, and HCFO-1233zd is preferable because it has excellent high critical temperature, durability, and coefficient of performance. HCFOs other than HCFO-1224yd may be used alone or in combination of two or more.

-Effects of the embodiment-
In the above embodiment, by using a refrigerant such as HFO-1123, the influence on the ozone layer and the influence of global warming can be suppressed. On the other hand, when a refrigerant containing a fluorinated hydrocarbon having such a disproportionation reaction is applied to a conventional compressor (see FIG. 12), it corresponds to points a, b, and c. There was a possibility that this refrigerant would cause a disproportionation reaction due to a local temperature rise in the portion where the heat treatment occurred.

In contrast, in this embodiment, the blade (51) that partitions the cylinder chamber (45) into the low pressure chamber (L) and the high pressure chamber (H) is integrally connected to the piston (44). For this reason, there is no sliding contact portion between the tip of the vane and the piston as in the rotary compressor. Therefore, it is possible to reliably avoid an increase in the temperature of the refrigerant at the tip of the blade (51).

As described above, the compression mechanism (40) of the present embodiment does not cause a local temperature increase at each sliding portion, unlike the portions of points a, b, and c of the conventional example. As a result, even when a refrigerant containing fluorocarbon hydrogen having the property of causing a disproportionation reaction is used, it is possible to prevent the disproportionation reaction from being caused inside the compression mechanism (40).

-Modification of the embodiment-
The compressor (30) of the above embodiment may be configured as the following modifications.

<Modification 1>
As illustrated in FIG. 5, the compression mechanism (40) of the first modification includes a plurality of compression units (61, 62). In this example, the first compression part (61) is provided near the lower part of the compression mechanism (40), and the second compression part (62) is provided near the upper part. A compression mechanism (40) is comprised so that a refrigerant | coolant may be compressed by each compression part (61, 62), respectively. In the compression mechanism (40) of the first modification, the refrigerant is compressed in parallel by the compression units (61, 62).

The compression mechanism (40) has a first cylinder (42a), a middle plate (50), a second cylinder (42b), a first piston (44a), and a second piston (44b). The drive shaft (35) of the compressor (30) is provided with a first crankshaft (37a) and a second crankshaft (37b). A first cylinder chamber (45a) is formed inside the first cylinder (42a), and a second cylinder chamber (45b) is formed inside the second cylinder (42b). A first crankshaft (37a) is fitted into the first piston (44a), and a second crankshaft (37b) is fitted into the second piston (44b).

The first compression part (61) corresponds to the first cylinder (42a) and the first piston (44a), and the second compression part (62) corresponds to the second cylinder (42b) and the second piston (44b). To do. Each compression section (61, 62) is provided with a back pressure chamber (54), a bush groove (53), a pair of bushes (52), and a blade (51), respectively, in the same manner as in the above embodiment (FIG. 4). It is done.

The first cylinder (42a) is formed with a first suction port (46a) communicating with the low pressure chamber (L) of the first cylinder chamber (45a). A first suction pipe (23a) is connected to the first suction port (46a). The second cylinder (42b) is formed with a second suction port (46b) communicating with the low pressure chamber (L) of the second cylinder chamber (45b). A second suction pipe (23b) is connected to the second suction port (46b).

The first discharge port (47a) communicating with the high pressure chamber (H) of the first cylinder chamber (45a) is formed in the rear head (43). The first discharge port (47a) communicates with the first muffler space (49a) of the first muffler (48a) that covers the rear head (43).

The second discharge port (47b) communicating with the high pressure chamber (H) of the second cylinder chamber (45b) is formed in the front head (41). The second discharge port (47b) communicates with the second muffler space (49b) of the second muffler (48b) that covers the front head (41).

When the drive shaft (35) is driven to rotate, the first piston (44a) and the second piston (44b) rotate eccentrically. In the first compression section (61), the low-pressure refrigerant sucked into the first cylinder chamber (45a) through the first suction pipe (23a) and the first suction port (46a) is compressed to a high pressure. The compressed refrigerant flows out into the internal space (S) through the first discharge port (47a) and the first muffler space (49a). At the same time, in the second compression section (62), the refrigerant sucked into the second cylinder chamber (45b) through the second suction pipe (23b) and the second suction port (46b) is compressed to a high pressure. The compressed refrigerant flows out to the internal space (S) through the second discharge port (47). The refrigerant joined in the internal space (S) flows around the electric motor (32), then flows out of the discharge pipe (22), and is sent to the refrigerant circuit (11).

Also in the modified example 1, the blades (51) of the compression portions (61, 62) are integrally connected to the pistons (44a, 44b), and the blades (51) are respectively connected to the pair of bushes (52). It is held so that it can move forward and backward. Thereby, like a prior art example, it can avoid that a local temperature rise is caused by a sliding part, and it can prevent that a refrigerant causes disproportionation reaction.

Also, in the first modification, the refrigerant is compressed in parallel by the plurality of compression units (61, 62), so that the rotational speed of the drive shaft (35) can be reduced. Therefore, in each compression part (61,62), the temperature rise in each sliding part accompanying rotation of a drive shaft (35) can be suppressed, and the disproportionation reaction of a refrigerant | coolant can be prevented more reliably.

<Modification 2>
Similar to the first modification, the compression mechanism (40) of the second modification has a plurality of compression sections (61, 62). In Modification 2, a plurality of compression units (61, 62) are connected in series. Specifically, the compression mechanism (40) includes a low-stage-side first compression section (61) and a high-stage-side second compression section (62), and is configured to perform two-stage compression. The

As shown in FIG. 6, a first relay pipe (63) communicating with the high pressure chamber (H) of the first cylinder chamber (45a) is connected to the first cylinder (42a). A second relay pipe (64) communicating with the low pressure chamber (L) of the first cylinder chamber (45a) is connected to the second cylinder (42b). The first relay pipe (63) and the second relay pipe (64) communicate with each other.

When the drive shaft (35) is driven to rotate, the first piston (44a) and the second piston (44b) rotate eccentrically. In the first compression section (61), the low-pressure refrigerant sucked into the first cylinder chamber (45a) via the suction pipe (23) and the suction port (46) is compressed to an intermediate pressure between the low pressure and the high pressure. The The refrigerant compressed to the intermediate pressure is sucked into the second cylinder chamber (45b) through the first relay pipe (63) and the second relay pipe (64). The refrigerant compressed to a high pressure in the second cylinder chamber (45b) flows out into the internal space (S) through the discharge port (47) and the muffler space (49). The refrigerant joined in the internal space (S) flows around the electric motor (32), then flows out of the discharge pipe (22), and is sent to the refrigerant circuit (11).

Also in the modified example 2, the blades (51) of the compression portions (61, 62) are integrally connected to the pistons (44a, 44b), respectively, and the blades (51) are respectively connected to the pair of bushes (52). It is held so that it can move forward and backward. Thereby, like a prior art example, it can avoid that a local temperature rise is caused by a sliding part, and it can prevent that a refrigerant causes disproportionation reaction.

In the second modification, the refrigerant is compressed in two stages in the two compression sections (61, 62). For this reason, compared with the case where a refrigerant | coolant is compressed with one compression part, the differential pressure | voltage (difference of suction pressure and discharge pressure) of the refrigerant | coolant in each compression part (61,62) becomes small. If it does in this way, in each compression part (61,62), since the differential pressure | voltage of a low pressure chamber (L) and a high pressure chamber (H) becomes small, the sliding resistance resulting from a differential pressure | voltage can be reduced. As a result, it is possible to suppress the temperature rise of the refrigerant in each compression section (61, 62).

<Modification 3>
The compressor (30) of Modification 3 is different from the compression mechanism (40) of Modification 1 in the shapes of the piston (44) and the cylinder (42). As shown in FIG. 7, the compression mechanism (40) of the third modification is configured as a so-called non-circular piston type. That is, in the compression mechanism (40) of the above-described embodiment, the cross-sectional shape of the inner peripheral surface of the cylinder (42) and the outer peripheral surface of the piston (44) is configured to be a perfect circle. On the other hand, in the modification 3, the cross-sectional shape of the inner peripheral surface of a cylinder (42) and the outer peripheral surface of a piston (44) is formed in non-circular shape (substantially egg shape).

Specifically, on the outer peripheral surface of the piston (44) of the present embodiment, a bulging surface (56) in which substantially half of the suction side (right side in FIG. 7) bulges radially outward across the blade (51). And approximately half of the discharge side (left side in FIG. 7) sandwiching the blade (51) forms a true circular arc surface (57) having a true arc shape. On the other hand, the inner peripheral surface shape of the cylinder (42) is formed in a non-circular shape corresponding to the outer peripheral surface shape of the piston (44). That is, the inner peripheral surface shape of the cylinder (42) is formed in a non-circular shape based on an envelope outside the outer peripheral surface of the piston (44) that performs the swinging motion. Specifically, the shape of the inner peripheral surface of the cylinder (42) is such that the right portion in FIG. 7 bulges radially outward and the left portion in FIG. 7 is formed in a true arc shape.

Also in the third modification, the blade (51) is integrally connected to the piston (44), and the blade (51) is held between the pair of bushes (52) so as to advance and retreat. Thereby, like a prior art example, it can avoid that a local temperature rise is caused by a sliding part, and it can prevent that a refrigerant causes disproportionation reaction.

Further, in the non-circular piston type compression mechanism (40) according to the modified example 3, the volume change rate during one rotation of the compression chamber (high pressure chamber (H)) is optimized according to the outer peripheral surface shape of the piston (44). it can. Due to the outer peripheral surface shape of the piston (44) shown in FIG. 7, the volume of the compression chamber can be quickly reduced as compared with a method in which the outer peripheral surface shape of the piston is a perfect circle (circular piston type) (see FIG. 8). Thereby, in the modification 3, the rotation angle near the discharge stroke becomes smaller than that of the circular piston type. As a result, in the modified example 3, compared with the circular piston type, the start timing of the discharge stroke becomes earlier, and the period of the discharge stroke can be lengthened. In this way, since over-compression in the discharge stroke can be suppressed, the high-low differential pressure (pressure difference between the high-pressure chamber (H) and the low-pressure chamber (L)) associated with over-compression is reduced. The sliding resistance due to pressure can be further reduced. As described above, in Modification 3, it is possible to avoid a local temperature increase at the sliding portion due to overcompression, and it is possible to more effectively suppress the refrigerant from causing a disproportionation reaction.

In the non-circular piston type compression mechanism (40), for example, the outer peripheral surface shape of the piston (44) may be an elliptical shape in which both the discharge side and the suction side are bulged.

<Modification 4>
The compressor (30) of Modification 4 differs from the above embodiment in the configuration of the compression mechanism (40). As shown in FIGS. 9 and 10, the compression mechanism (40) includes a fixed member (71) fixed to the casing (31) and a movable member (72) connected to the crankshaft (37) of the drive shaft (35). ).

The fixing member (71) has a fixed side end plate portion (73), an outer edge portion (74), and an intermediate cylinder (75) (cylinder). The fixed side end plate portion (73) is formed in a flat disk shape. The outer edge portion (74) is formed in a substantially cylindrical shape that protrudes downward in the axial direction from the outer peripheral edge portion of the fixed-side end plate portion (73). The intermediate cylinder (75) protrudes downward in the axial direction from between the axial center portion and the outer peripheral end portion of the fixed-side end plate portion (73). The intermediate cylinder (75) is formed in an annular shape (shaped in a cross section C) that is coaxial with the axis of the drive shaft (35) and is partially cut away.

A bush groove (53) similar to that of the embodiment is formed in the cut portion of the intermediate cylinder (75). A pair of bushes (52) is held in the bush groove (53) so as to be swingable. A blade groove (55) for holding the blade (51) is formed between the pair of bushes (52).

The movable member (72) has a movable side end plate portion (76), an inner piston (77) (piston), and an outer piston (78). The movable side end plate portion (76) is formed in a disc shape into which the crankshaft (37) is fitted. The inner piston (77) projects upward in the axial direction from the inner peripheral edge of the movable side end plate (76). The inner piston (77) is formed in a cylindrical shape into which the crankshaft (37) is fitted. The outer piston (78) protrudes upward in the axial direction from the outer peripheral edge portion of the movable side end plate portion (76). In the compression mechanism (40), an inner cylinder chamber (81) is formed between the inner piston (77) and the intermediate cylinder (75), and an outer cylinder chamber (81) is formed between the intermediate cylinder (75) and the outer piston (78). 82) is formed.

The blade (51) of Modification 4 is provided on the movable member (72). The blade (51) is integrally connected to the outer peripheral surface of the inner piston (77) and the inner peripheral surface of the outer piston (78). The blade (51) is held in the bush groove (53) so as to be able to advance and retreat. The inner cylinder chamber (81) and the outer cylinder chamber (82) are partitioned into a high pressure chamber (H) and a low pressure chamber (L) by a blade (51), respectively.

As shown in FIG. 10, the fixing member (71) is formed with a suction port (46) communicating with the low pressure chamber (L) of each cylinder chamber (45). The fixing member (71) is formed with two discharge ports (47) communicating with the high pressure chambers (H) of the cylinder chambers (45).

In the compression mechanism (40) of Modification 4, the inner piston (77) and the outer piston (78) rotate eccentrically with the rotation of the drive shaft (35). When the volume of the low pressure chamber (L) of the inner cylinder chamber (81) gradually increases with the eccentric rotation of the inner piston (77), the low pressure refrigerant flows through the suction port (46) into the low pressure chamber (81) of the inner cylinder chamber (81). Inhaled to L). When the inner piston (77) further eccentrically rotates, the low pressure chamber (L) of the inner cylinder chamber (81) becomes the high pressure chamber (H), and the refrigerant in the high pressure chamber (H) is discharged from the discharge port (47). At the same time, when the volume of the low pressure chamber (L) of the outer cylinder chamber (82) gradually increases with the eccentric rotation of the outer piston (78), the low pressure refrigerant passes through the suction port (46) and the low pressure of the outer cylinder chamber (82). It is inhaled into the room (L). When the outer piston (78) further eccentrically rotates, the low pressure chamber (L) of the outer cylinder chamber (82) becomes the high pressure chamber (H), and the refrigerant in the high pressure chamber (H) is discharged from the discharge port (47).

Also in the modified example 4, the blade (51) is integrally connected to the inner piston (77) and the outer piston (78), and the blade (51) can be moved back and forth between the pair of bushes (52). Retained. Thereby, like a prior art example, it can avoid that a local temperature rise is caused by a sliding part, and it can prevent that a refrigerant causes disproportionation reaction.

<Modification 5>
The compressor (30) of Modification 5 has a compression mechanism (40) similar to that of Modification 4.

As shown in FIGS. 11 and 12, the fixing member (71) of Modification 5 has a fixed side end plate portion (73), an inner piston (77) (piston), and an outer piston (78). The outer piston (78) is formed in an annular shape that protrudes downward in the axial direction from the outer peripheral edge portion of the fixed-side end plate portion (73). The inner piston (77) is formed in an annular shape that protrudes downward in the axial direction from between the shaft center portion and the outer peripheral end portion of the fixed-side end plate portion (73). The outer piston (78) and the inner piston (77) are coaxial with the axis of the drive shaft (35).

The movable member (72) of the modified example 5 has a movable side end plate portion (76), a boss portion (79), and an intermediate cylinder (75) (cylinder). The boss portion (79) protrudes upward in the axial direction from the inner peripheral edge portion of the movable side end plate portion (76). The boss portion (79) is formed in a cylindrical shape into which the crankshaft (37) is fitted. The intermediate cylinder (75) protrudes upward in the axial direction from the outer peripheral portion of the movable side end plate portion (76). In the compression mechanism (40), an inner cylinder chamber (81) is formed between the inner piston (77) and the intermediate cylinder (75), and an outer cylinder chamber (81) is formed between the intermediate cylinder (75) and the outer piston (78). 82) is formed.

The blade (51) of the modified example 5 is provided on the fixing member (71). The blade (51) is integrally connected to the outer peripheral surface of the inner piston (77) and the inner peripheral surface of the outer piston (78). The blade (51) is held in the bush groove (53) so as to be able to advance and retreat. The inner cylinder chamber (81) and the outer cylinder chamber (82) are partitioned into a high pressure chamber (H) and a low pressure chamber (L) by a blade (51), respectively.

As shown in FIG. 12, the fixing member (71) is formed with a suction port (46) communicating with the low pressure chamber (L) of each cylinder chamber (45). The fixing member (71) is formed with two discharge ports (47) communicating with the high pressure chambers (H) of the cylinder chambers (45).

In the compression mechanism (40) of Modification 5, the intermediate cylinder (75) rotates eccentrically with the rotation of the drive shaft (35). When the volume of the low pressure chamber (L) of the inner cylinder chamber (81) gradually increases with the eccentric rotation of the intermediate cylinder (75), the low pressure refrigerant passes through the suction port (46) to the low pressure chamber (81) of the inner cylinder chamber (81). Inhaled to L). When the intermediate cylinder (75) further rotates eccentrically, the low pressure chamber (L) of the inner cylinder chamber (81) becomes the high pressure chamber (H), and the refrigerant in the high pressure chamber (H) is discharged from the discharge port (47). At the same time, when the volume of the low pressure chamber (L) of the outer cylinder chamber (82) gradually increases with the eccentric rotation of the intermediate cylinder (75), the low pressure refrigerant passes through the suction port (46) and the low pressure of the outer cylinder chamber (82). It is inhaled into the room (L). When the intermediate cylinder (75) further rotates eccentrically, the low pressure chamber (L) of the outer cylinder chamber (82) becomes the high pressure chamber (H), and the refrigerant in the high pressure chamber (H) is discharged from the discharge port (47).

Also in the modified example 5, the blade (51) is integrally connected to the inner piston (77) and the outer piston (78), and the blade (51) can be moved back and forth between the pair of bushes (52). Retained. Thereby, like a prior art example, it can avoid that a local temperature rise is caused by a sliding part, and it can prevent that a refrigerant causes disproportionation reaction.

<< Other Embodiments >>
About the said embodiment and each modification, it is good also as following structures.

The refrigeration apparatus of the above embodiment is an air conditioner (10) that performs indoor cooling and heating. However, the refrigeration apparatus may be any apparatus as long as it has a refrigerant circuit and performs a refrigeration cycle. For example, you may employ | adopt the freezing apparatus of this invention for the freezing apparatus for refrigeration and freezer which cools the inside of a store | warehouse | chamber, a chiller unit, a water heater, etc.

The configuration of the compression mechanism according to the above embodiment and each modification may be combined as appropriate.

As described above, the present invention is useful for a refrigeration apparatus.

10 Air conditioning equipment (refrigeration equipment)
11 Refrigerant circuit 30 Compressor 32 Electric motor 40 Compression mechanism 42 Cylinder 42a First cylinder (cylinder)
42b Second cylinder (cylinder)
44 piston 44a first piston (piston)
44b Second piston (piston)
45 Cylinder chamber 45a First cylinder chamber (cylinder chamber)
45b Second cylinder chamber (cylinder chamber)
51 Blade 52 Bush 53 Bush Groove 61 First Compression Section (Compression Section)
62 2nd compression part (compression part)
75 Intermediate cylinder (cylinder)
77 Inner piston (piston)
H High pressure chamber L Low pressure chamber

Claims

A refrigeration apparatus comprising a refrigerant circuit (11) to which a compressor (30) for compressing refrigerant is connected,
The refrigerant is a refrigerant containing a fluorinated hydrocarbon having a property of causing a disproportionation reaction,
The compressor (30) includes an electric motor (32) and a compression mechanism (40) driven by the electric motor (32).
The compression mechanism (40)
The cylinder (42,42a, 42b, 75) in which the cylinder chamber (45,45a, 45b, 81,82) is formed, and the piston (44) accommodated in the cylinder chamber (45,45a, 45b, 81,82) , 44a, 44b, 77)
A blade (51) which is integrally connected to the piston (44,44a, 44b, 77) and partitions the cylinder chamber (45,45a, 45b, 81,82) into a low pressure chamber (L) and a high pressure chamber (H) When,
A pair of bushes (52) that are swingably held in a pair of bush grooves (53) formed in the cylinder (42, 42a, 42b, 75) and that hold the blade (51) forward and backward. Have
A refrigeration apparatus, wherein the piston (44, 44a, 44b, 77) and the cylinder (42, 42a, 42b, 75) are configured to rotate relatively eccentrically.
In claim 1,
The compression mechanism (40) has a plurality of compression parts (61, 62) each having the cylinder (42a, 42b), the piston (44a, 44b), the blade (51), and the bush (52). And a refrigeration apparatus configured to compress the refrigerant in parallel by the plurality of compression units (61, 62).
In claim 1,
The compression mechanism (40) has a plurality of compression parts (61, 62) each having the cylinder (42a, 42b), the piston (44a, 44b), the blade (51), and the bush (52). A refrigeration apparatus comprising the plurality of compression units (61, 62) connected in series.
In any one of Claims 1 thru | or 3,
The compression mechanism (40) includes the cylinder (42) having a non-circular inner peripheral surface and the piston (44) having a non-circular outer peripheral surface, and the piston (44) rotates eccentrically. A refrigeration apparatus comprising a non-circular piston type.
In any one of Claims 1 thru | or 4,
The refrigeration apparatus, wherein the refrigerant is a refrigerant containing HFO-1123.