CN106337814A - Compressor and refrigeration cycle device - Google Patents

Abstract

The compressor and refrigeration cycle device of the present invention are provided with a compression mechanism and a discharge valve. The discharge valve is configured to include: a fixed portion fixed to the compression mechanism; a front end portion that freely opens and closes a discharge port (73) for discharging refrigerant compressed in a space (72) of the compression mechanism; and a middle portion that connects the fixed portion and the front end portion and, together with the front end portion, freely opens and closes the discharge port (73). The width (a) of the opening area of the discharge port (73) at a position of the compression mechanism opposite to the middle portion of the discharge valve is smaller than the width (b) of the opening area of the discharge port (73) at a position of the compression mechanism opposite to the front end of the discharge valve.

Description

Compressor and refrigeration cycle device

technical field

The invention relates to a compressor and a refrigeration cycle device.

Background technique

The hermetic rotary compressor includes an airtight container, a compression mechanism housed in a lower portion of the airtight container, and a motor housed in an upper portion of the airtight container to drive the compression mechanism. The compression mechanism includes a cylindrical cylinder, bearings closing the upper and lower ends of the cylinder, and an annular piston housed in the cylinder. The bearing supports the crankshaft that transmits the torque of the electric motor to the compression mechanism. A discharge port for discharging compressed gas is provided on the bearing. The piston is fitted to the eccentric portion of the crankshaft.

Conventionally, there is a hermetic rotary compressor in which a discharge port of a bearing is elliptical (for example, refer to Patent Document 1).

Patent Document 1: Japanese Patent Laid-Open No. 2012-140908

In the hermetic rotary compressor, since the crankshaft rotates synchronously with the rotation of the rotor of the electric motor, the piston rotates eccentrically to change the volume of the compression chamber in the cylinder. As the volume of the compression chamber changes, the refrigerant is sucked into the compression chamber and compressed. The compressed refrigerant is discharged from the discharge port of the bearing. The discharged refrigerant passes through the upper part of the airtight container, and is discharged to the outside of the airtight container as a high-pressure refrigerant.

In such a hermetic rotary compressor, it is desirable that the discharge port of the bearing is arranged so as to satisfy the following conditions.

Condition 1: The discharge port does not interfere with a plurality of bolts for fastening the cylinder block and bearings and holes into which the plurality of bolts are inserted.

Condition 2: When the compression chamber is formed in the cylinder, the space inside the inner circumference of the piston is not connected to the discharge port.

Condition 3: The area of the discharge port becomes the optimum area.

If the condition 1 is not satisfied, the cylinder block and the bearing are fastened with only a part of the bolts, and the reliability of the compression mechanism decreases.

When condition 2 is not satisfied, the high-pressure refrigerant passes inside the piston and flows into the low-pressure space, causing compression loss.

In the case where condition 3 is not satisfied, the flow path resistance at the discharge port increases, causing overcompression. As a result, the workload of the compression action increases, and the performance of the compression mechanism decreases.

Hermetic rotary compressors tend to flatten the cylinder and increase the eccentricity of the piston in order to maintain the reliability of the compression mechanism, increase the efficiency of the compression mechanism, and increase the capacity in a small-diameter hermetic container. In order to flatten the cylinder or increase the eccentricity of the piston to satisfy condition 3, it is necessary to enlarge the discharge port. However, if the discharge port is enlarged while the discharge port is circular or elliptical, the sealing length between the discharge port and the piston will decrease, making it difficult to satisfy condition 2. As a result, the effectiveness of hermetic rotary compressors is reduced. If the center of the discharge port is moved outward, the sealing length between the discharge port and the piston can be ensured, but it is difficult to satisfy condition 1. As a result, the reliability of the hermetic rotary compressor decreases. In addition, "the sealing length between the discharge port and the piston" means the distance between the discharge port and the inner periphery of the piston.

In addition, when the flow rate of the refrigerant increases due to the increase in capacity, the possibility of damage to the discharge valve, which is a valve attached to the discharge port, increases. Specifically, when the discharge valve is raised, stress is concentrated on a part of the discharge valve, or when the discharge valve is seated, impact stress is increased, and the discharge valve may be damaged. As a result, the reliability of the hermetic rotary compressor decreases.

Contents of the invention

An object of the present invention is to increase the capacity of the compressor while maintaining the reliability and effectiveness of the compressor.

A compressor according to one aspect of the present invention includes:

a compression mechanism formed with a space for compressing refrigerant, and a discharge port for discharging refrigerant compressed in the space; and

A discharge valve comprising a fixed portion, a front end portion fixed to the compression mechanism, and a middle portion, the front end portion closing the discharge port freely, and the middle portion closing the discharge port. The fixing part is connected to the front end, and together with the front end, closes the discharge port openably and closably,

A width of an opening area of the discharge port at a position opposing the intermediate portion of the compression mechanism is smaller than an opening area of the discharge port at a position opposing the front end of the compression mechanism. width.

In one example, an opening area of the discharge port at a position of the compression mechanism facing the intermediate portion gradually narrows toward a position of the compression mechanism facing the fixing portion.

In one example, the opening area of the discharge port has a shape in which two circles having different diameters are connected by two lines having tangent points on both sides of the two circles.

In one example, the compression mechanism includes: a ring-shaped piston forming the space at a position outside the outer circumference of the piston, and the piston rotates eccentrically; Ratio, the space is divided into a low-pressure suction chamber and a high-pressure compression chamber, and a part of the opening area of the discharge port has a shape that is curved to form the suction chamber integrally with the piston in the space. Concentric circular arc shape with inner circumference in the rotated position.

In one example, the opening area of the discharge port has a shape in which two circles with different diameters are connected by two lines having tangent points on both sides of the two circles, and the two circles One of the lines is a circular arc concentric with the inner circumference of the piston when the entire space becomes the rotation position of the suction chamber.

In one example, the compression mechanism further includes: a cylinder forming the space inside the inner periphery of the cylinder; a bearing forming the discharge port and a circular fastening hole, and The fastener inserted into the fastening hole is fixed to the cylinder to support the rotation shaft of the piston, and the other part of the opening area of the discharge port is bent so as to be concentric with the circumference of the fastening hole. arc-like shape.

In one example, the opening area of the discharge port has a shape in which two circles with different diameters are connected by two lines having tangent points on both sides of the two circles, and the two circles One of the lines is an arc concentric with the inner circumference of the piston when the space as a whole becomes the rotation position of the suction chamber, and the other of the two lines is concentric with the circumference of the fastening hole. arc.

A refrigeration cycle apparatus according to an aspect of the present invention includes a refrigerant circuit connected to the compressor according to any one of the above, and circulates the refrigerant.

In the present invention, since the discharge port formed in the compression mechanism has such a size that it is closed not only by the front end portion of the discharge valve but also by the middle portion of the discharge valve, the capacity of the compressor can be increased. The discharge port is closed by the middle portion of the discharge valve, and the concentration of stress on a part of the discharge valve and the increase of impact stress when the discharge valve is seated can be suppressed, so that the discharge valve is less likely to be damaged. Therefore, the reliability of the compressor can be maintained. In addition, since the width of the opening area of the discharge port is reduced at the position closed by the middle portion of the discharge valve, the sealing length of the discharge port and the piston can be ensured. The effectiveness of the compressor can thus also be maintained.

Description of drawings

FIG. 1 is a circuit diagram of a refrigeration cycle apparatus according to Embodiment 1. FIG.

FIG. 2 is a circuit diagram of a refrigeration cycle apparatus according to Embodiment 1. FIG.

Fig. 3 is a longitudinal sectional view of the compressor according to the first embodiment.

FIG. 4 is a plan view of a discharge valve of the compressor according to Embodiment 1. FIG.

FIG. 5 is a partial cross-sectional view of the compressor according to Embodiment 1. FIG.

6 is an A-A sectional view of the compressor according to Embodiment 1. FIG.

FIG. 7 is a partial cross-sectional view of a compressor according to Embodiment 2. FIG.

Explanation of reference numerals: 10...refrigeration cycle device; 11...refrigerant circuit; 12...compressor; 13...four-way valve; 14...first heat exchanger; 15...expansion mechanism; 16...second heat exchanger; 17 …control device; 20…airtight container; 21…suction pipe; 22…discharge pipe; 23…suction muffler; 24…terminal; 30…compression mechanism; 31…cylinder; 32…piston; 33…blade; 34…main bearing ;35...Auxiliary bearing; 36...Exhaust muffler; 37...Fastener; 40...Motor; 41...Stator; 42...Rotor; 43...Stator core; 44...Coil; 46...Rotor core; 50...Crankshaft; 51...Eccentric Shaft part; 52...Main shaft part; 53...Counter shaft part; 60...Discharge valve; 61...Fixed part; 62...Middle part; 63...Front part; 64...Through hole; ...space; 73...discharge port; 74...surrounding wall; 75...inner periphery; 76...cylinder chamber; 77...blade groove; 78...inner periphery; 79...outer periphery; 81...fastening hole; 82...valve groove; 83 ...shallow groove; 84...deep groove.

detailed description

Embodiments of the present invention will be described below using the drawings. In addition, in each figure, the same code|symbol is attached|subjected to the same or corresponding part. In the description of the embodiments, the description of the same or corresponding parts is appropriately omitted or simplified. In addition, in the description of the embodiment, the arrangement, orientation, etc. of "upper", "lower", "left", "right", "front", "rear", "front", "back", etc. are for convenience of description. , is only marked in the above manner, and does not limit the arrangement, direction, etc. of devices, appliances, components, etc. The materials, shapes, sizes, etc. of the structures of devices, appliances, and components can be appropriately changed within the scope of the present invention.

Embodiment 1

The configuration of the apparatus and equipment of this embodiment, the operation of the equipment of this embodiment, and the effect of this embodiment will be described in order.

Structure Description

1 and 2, the structure of the refrigeration cycle apparatus 10 which is an apparatus of this embodiment is demonstrated.

Fig. 1 shows the refrigerant circuit 11 during cooling operation. FIG. 2 shows the refrigerant circuit 11 during heating operation.

The refrigeration cycle device 10 is an air conditioner in this embodiment, but may be a device other than an air conditioner such as a refrigerator or a heat pump cycle device.

The refrigeration cycle device 10 includes a refrigerant circuit 11 through which a refrigerant circulates.

Connected to the refrigerant circuit 11 are: a compressor 12, a four-way valve 13, a first heat exchanger 14 as an outdoor heat exchanger, an expansion mechanism 15 as an expansion valve, and a second heat exchanger as an indoor heat exchanger. 16. The compressor 12 compresses the refrigerant. The four-way valve 13 switches the direction in which the refrigerant flows during cooling operation and heating operation. During the cooling operation, the first heat exchanger 14 operates as a condenser to dissipate heat from the refrigerant compressed by the compressor 12 . During the heating operation, the first heat exchanger 14 operates as an evaporator, and heats the refrigerant by exchanging heat between outdoor air and the refrigerant expanded by the expansion mechanism 15 . The expansion mechanism 15 expands the refrigerant that has dissipated heat from the condenser. During the heating operation, the second heat exchanger 16 operates as a condenser to dissipate heat from the refrigerant compressed by the compressor 12 . During cooling operation, the second heat exchanger 16 operates as an evaporator, and heats the refrigerant by exchanging heat between the indoor air and the refrigerant expanded by the expansion mechanism 15 .

The refrigeration cycle device 10 further includes a control device 17 .

The control device 17 is specifically a microcomputer. In FIGS. 1 and 2 , only the control device 17 is shown connected to the compressor 12 , but the control device 17 is connected not only to the compressor 12 but also to various elements connected to the refrigerant circuit 11 . The control device 17 monitors or controls the state of each element.

As the refrigerant circulating in the refrigerant circuit 11, any refrigerant such as R32 refrigerant, R290 (propane) refrigerant, R407C refrigerant, R410A refrigerant, R744 (CO 2 ) refrigerant, or R1234yf refrigerant can be used.

Referring to FIG. 3, the structure of the compressor 12 which is an apparatus of this embodiment is demonstrated.

FIG. 3 shows a longitudinal section of the compressor 12 . In addition, in FIG. 3, the hatching which shows a cross-section is abbreviate|omitted.

The compressor 12 is a two-cylinder rotary compressor in this embodiment, but may be a single-cylinder rotary compressor, a three-cylinder or more rotary compressor, or a scroll compressor.

The compressor 12 includes an airtight container 20 , a compression mechanism 30 , a motor 40 , a crankshaft 50 , and a discharge valve 60 .

A suction pipe 21 for sucking in the refrigerant and a discharge pipe 22 for discharging the refrigerant are attached to the airtight container 20 .

The compression mechanism 30 is accommodated inside the airtight container 20 . Specifically, the compression mechanism 30 is provided at the inner lower portion of the airtight container 20 . Compression mechanism 30 is driven by electric motor 40 . The compression mechanism 30 compresses the refrigerant sucked into the suction pipe 21 .

The motor 40 is also accommodated inside the airtight container 20 . Specifically, the motor 40 is provided on the inner upper portion of the airtight container 20 . The electric motor 40 is a concentrated winding motor in this embodiment, but may be a distributed winding motor.

Refrigerator oil for lubricating each sliding part of the compression mechanism 30 is stored in the bottom of the airtight container 20 . Refrigerator oil is sucked up by an oil pump provided below the crankshaft 50 as the crankshaft 50 rotates, and supplied to each sliding portion of the compression mechanism 30 . As the refrigerating machine oil, synthetic oils such as POE (polyol ester), PVE (polyvinyl ether), AB (alkylbenzene) and the like are used.

Hereinafter, the motor 40 will be described in detail.

The motor 40 is a brushless DC (Direct·Current) motor in this embodiment, but may be a motor other than a brushless DC motor such as an induction motor.

The motor 40 includes a cylindrical stator 41 and a cylindrical rotor 42 .

The stator 41 contacts and is fixed to the inner peripheral surface of the airtight container 20 . The rotor 42 is provided inside the stator 41 with a gap of about 0.3 to 1.0 mm.

The stator 41 includes a stator core 43 and a coil 44 . The stator core 43 is produced by punching out a plurality of electromagnetic steel sheets with a thickness of 0.1 to 1.5 mm mainly composed of iron into a certain shape, stacking them in the axial direction, and fixing them by riveting or welding. The coil 44 is wound around the stator core 43 in a concentrated winding manner via an insulating member. The coil 44 is configured to include a core wire and at least one film covering the core wire. In this embodiment, the material of the core wire is copper. The material of the film is AI (amide imide)/EI (ester imide). The material of the insulating part is PET (polyethylene terephthalate). In addition, the material of the core wire may be aluminum. The material of the insulating part can also be PBT (polybutylene terephthalate), FEP (tetrafluoroethylene-hexafluoropropylene copolymer), PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), PTFE (polytetrafluoroethylene), LCP (liquid crystal polymer), PPS (polyphenylene sulfide), or phenolic resin. One end of a lead wire (not shown) is connected to the coil 44 .

The rotor 42 includes a rotor core 46 and permanent magnets (not shown). The rotor core 46 is the same as the stator core 43, and is produced by punching a plurality of electromagnetic steel plates with iron as the main component and a thickness of 0.1 to 1.5 mm into a certain shape, stacking them in the axial direction, and riveting or welding Wait for it to be fixed. The permanent magnets are inserted into a plurality of insertion holes formed in the rotor core 46 . The permanent magnets form the magnetic poles. Ferrite magnets or rare earth magnets are used as permanent magnets.

Although not shown, a shaft hole is formed at the center of the rotor core 46 in plan view, and the main shaft portion 52 of the crankshaft 50 is shrink-fitted or press-fitted. A plurality of through holes penetrating in the axial direction are formed around the shaft hole of the rotor core 46 . Each of the through holes serves as one of passages for the gas refrigerant released from the discharge muffler 36 to the space in the airtight container 20 .

Although not shown, when the motor 40 is configured as an induction motor, conductors made of aluminum, copper, or the like are filled or inserted into the plurality of slots formed in the rotor core 46 . Then form a cage coil in which both ends of the conductor are short-circuited with end rings.

A terminal 24 connected to an external power source such as an inverter device is attached to the top of the airtight container 20 . Terminal 24 is specifically a glass terminal. In this embodiment, the terminal 24 is fixed to the airtight container 20 by welding. The other end of the lead wire described above is connected to the terminal 24 . The terminal 24 is thereby electrically connected to the coil 44 of the motor 40 .

On the top of the airtight container 20 is installed a discharge pipe 22 which is open at both ends in the axial direction. The gas refrigerant discharged from the compression mechanism 30 is discharged from the space in the airtight container 20 to the external refrigerant circuit 11 through the discharge pipe 22 .

Hereinafter, the discharge valve 60 will be described in detail with reference to FIG. 4 .

The discharge valve 60 is configured to include a fixed portion 61 , a middle portion 62 , and a front end portion 63 . In this embodiment, the discharge valve 60 is integrally formed of a long plate member, one end in the longitudinal direction is the fixed portion 61 , the central portion in the longitudinal direction is the middle portion 62 , and the other end in the longitudinal direction is the front end. Section 63.

The fixing portion 61 is fixed to the compression mechanism 30 . In the present embodiment, the fixing portion 61 is provided with a through hole 64 , and the fixing portion 61 is fixed to the compression mechanism 30 by a fixing member such as a screw inserted into the through hole 64 .

The middle part 62 connects the fixed part 61 and the front end part 63 . In this embodiment, the width x of the intermediate portion 62 is smaller than the width w of the fixed portion 61 .

The front end portion 63 has a neck portion 65 that is a portion connected to the middle portion 62 . In the present embodiment, the dimension in the width direction of the front end portion 63 gradually increases from the side connected to the intermediate portion 62 toward the opposite side, and gradually decreases from the middle. The portion where the dimension in the width direction gradually decreases is semicircular in plan view. The length of the diameter of this portion is equal to the maximum value of the dimension in the width direction of the front end portion 63 , that is, the width y of the front end portion 63 .

Hereinafter, the compression mechanism 30 will be described in detail with reference to FIGS. 5 and 6 in addition to FIG. 3 .

FIG. 5 shows a cross-section of a portion of compressor 12 . In addition, in FIG. 5, the hatching which shows a cross section is abbreviate|omitted. In addition, for convenience of description, the fastener 37 and the discharge valve 60 are omitted in FIG. 5 , and only a part of the compression mechanism 30 and the crankshaft 50 are shown. FIG. 6 shows a cut surface when the compression mechanism 30 is cut along the line A-A shown in FIG. 5 . In addition, in FIG. 6 , except for a part, the hatching indicating the cross section is omitted. Also in FIG. 6 , the crankshaft 50 is omitted.

The compression mechanism 30 is formed with: a suction port 71 for sucking gas refrigerant from the refrigerant circuit 11; a space 72 for compressing the refrigerant sucked in from the suction port 71; The refrigerant compressed in the space 72 is discharged to the refrigerant circuit 11 .

The compression mechanism 30 has a cylinder 31 , a piston 32 , a vane 33 , a main bearing 34 , and a sub bearing 35 . In the present embodiment, since the compressor 12 is a two-cylinder rotary compressor, the cylinder 31 , the piston 32 , and the vane 33 are respectively provided one at the upper part and one at the lower part.

The inner periphery 75 of the cylinder 31 is circular in plan view. A cylinder chamber 76 which is a circular space in plan view is formed inside the cylinder 31 . Both axial ends of the cylinder body 31 are open.

The cylinder 31 is provided with a vane groove 77 which is connected to the cylinder chamber 76 and extends in the radial direction. Although not shown, a back pressure chamber which is a circular space in a plan view connected to the vane groove 77 is formed outside the vane groove 77 .

The piston 32 is annular. Therefore, the inner circumference 78 and the outer circumference 79 of the piston 32 are circular in plan view. Piston 32 rotates eccentrically within cylinder chamber 76 . The piston 32 is slidably fitted to an eccentric shaft portion 51 of a crankshaft 50 serving as a rotation axis of the piston 32 .

The blade 33 is in the shape of a plate with a rounded tip. The vane 33 is disposed in the vane groove 77 of the cylinder 31 . The vane 33 is always pressed against the piston 32 by a vane spring provided in the back pressure chamber. Since the inside of the airtight container 20 is under high pressure, when the operation of the compressor 12 starts, the surface of the blade 33 on the side of the back pressure chamber, that is, the back surface of the blade acts on the pressure difference between the pressure in the airtight container 20 and the pressure in the cylinder chamber 76. force generated. Therefore, the main purpose of using the vane spring is to press the vane 33 against the piston 32 when the compressor 12 is started in which there is no pressure difference between the airtight container 20 and the cylinder chamber 76 .

The main bearing 34 has an inverted T shape when viewed from the side. The main bearing 34 is slidably fitted in the main shaft portion 52 which is a portion above the eccentric shaft portion 51 of the crankshaft 50 . The main bearing 34 closes the upper side of the cylinder chamber 76 and the vane groove 77 of the cylinder 31 .

The sub-bearing 35 is T-shaped when viewed from the side. The sub bearing 35 is slidably fitted in the sub shaft portion 53 which is a portion of the crankshaft 50 lower than the eccentric shaft portion 51 . The sub-bearing 35 closes the cylinder chamber 76 of the cylinder 31 and the lower side of the vane groove 77 .

In addition, although the main bearing 34 side structure is shown in FIG. 5 and FIG. 6, the sub bearing 35 side also has the same structure.

The suction port 71 is connected to the cylinder chamber 76 from the outer peripheral surface of the cylinder 31 . The space 72 for compressing the refrigerant is formed inside the inner circumference 75 of the cylinder 31 and outside the outer circumference 79 of the piston 32 . That is, the space 72 for compressing refrigerant is formed between the inner circumference 75 of the cylinder 31 and the outer circumference 79 of the piston 32 . The vane 33 divides the space 72 into a low-pressure suction chamber and a high-pressure compression chamber at a ratio corresponding to the rotational position of the piston 32 .

The discharge port 73 is formed in two bearings of the main bearing 34 and the sub bearing 35 . The discharge port 73 is formed on the side where the suction port 71 is located and the opposite side across the center line of the vane 33 at each bearing. That is, the discharge port 73 is formed at a position connected to the compression chamber when the space 72 of the compression mechanism 30 is divided into a suction chamber and a compression chamber by the vane 33 .

A circular fastening hole 81 is also formed in each bearing. Each bearing is fixed to the cylinder block 31 via a fastener 37 inserted into the fastening hole 81 , and supports the crankshaft 50 which is the rotation axis of the piston 32 . The main bearing 34 is specifically fixed to the upper cylinder block 31 . The sub bearing 35 is specifically fixed to the lower cylinder block 31 . The fastener 37 is a combination of a bolt and a nut in this embodiment. The number of fastening holes 81 may be appropriately adjusted, but each bearing requires a plurality of fastening holes 81 .

A valve groove 82 is also formed in each bearing. The valve groove 82 is configured to include a shallow groove portion 83 and a deep groove portion 84 . The fixing portion 61 of the discharge valve 60 is housed and fixed in the shallow groove portion 83 . A discharge port 73 is provided at the bottom of the deep groove portion 84 . The middle portion 62 and the front end portion 63 of the discharge valve 60 are housed in the deep groove portion 84 . The front end portion 63 closes the discharge port 73 in an openable and closable manner. The intermediate portion 62 closes the discharge port 73 in an openable and closable manner together with the front end portion 63 . The intermediate portion 62 and the front end portion 63 are in contact with the end surface of the peripheral wall portion 74 of the discharge port 73 when the discharge port 73 is closed. The thickness of the peripheral wall portion 74 of the discharge port 73 is constant. The height of the peripheral wall portion 74 of the discharge port 73 is equal to the difference in depth between the shallow groove portion 83 and the deep groove portion 84 . That is, the end surface of the peripheral wall portion 74 of the discharge port 73 is at the same position as the bottom surface of the deep groove portion 84 in the height direction of the peripheral wall portion 74 . In addition, the intermediate portion 62 may be arranged across the shallow groove portion 83 and the deep groove portion 84 .

A discharge muffler 36 is mounted on the outer side of each bearing. The high-temperature and high-pressure gas refrigerant discharged through the discharge valve 60 temporarily enters the discharge muffler 36 and is released from the discharge muffler 36 into the space in the airtight container 20 . In addition, the discharge valve 60 and the discharge muffler 36 may be provided only in either one of the main bearing 34 and the sub bearing 35 .

In this embodiment, the cylinder block 31 , the main bearing 34 and the auxiliary bearing 35 are made of sintered steel, but they may also be gray cast iron or carbon steel. The material of the piston 32 is alloy steel containing chromium or the like. The blade 33 is made of high-speed tool steel.

A suction muffler 23 is provided beside the airtight container 20 . The suction muffler 23 sucks low-pressure gas refrigerant from the refrigerant circuit 11 . The suction muffler 23 suppresses the direct entry of liquid refrigerant into the cylinder chamber 76 of the cylinder 31 in the event of return of the liquid refrigerant. The suction muffler 23 is connected to the suction port 71 via the suction pipe 21 . The main body of the suction muffler 23 is fixed to the side surface of the airtight container 20 by welding or the like.

Hereinafter, the discharge port 73 formed in the compression mechanism 30 will be described in detail.

In the present embodiment, the discharge port 73 has such a size that it is closed not only by the front end portion 63 of the discharge valve 60 but also by the middle portion 62 of the discharge valve 60 . Therefore, it is possible to increase the capacity of the compressor 12 .

Assuming that the discharge port 73 is closed only by the front end portion 63, when the discharge valve 60 rises, due to the difference in rigidity between the middle portion 62 and the front end portion 63, stress concentrates on the neck of the front end portion 63, which may damage the discharge valve 60. However, in the present embodiment, since the discharge port 73 is also closed by the intermediate portion 62, such stress concentration is suppressed, and the discharge valve 60 is hardly damaged. Therefore, the reliability of the compressor 12 can be maintained.

Assuming that in the state where the discharge port 73 is circular or elliptical, the discharge port 73 is also increased to the extent that it is closed by the middle part 62, then not only the sealing length f between the discharge port and the piston 32 is reduced, but also the sealing length f in the cylinder 31 is reduced. When forming the compression chamber, it is possible to connect the space inside the inner periphery 78 of the piston 32 to the discharge port 73 . However, in this embodiment, the width a of the opening region of the discharge port 73 at the position facing the intermediate portion 62 of the compression mechanism 30 is smaller than the width a of the discharge port 73 at the position facing the front end portion 63 of the compression mechanism 30 . The width b of the opening area. Therefore, the sealing length f between the discharge port 73 and the piston 32 can be ensured. The effectiveness of the compressor 12 can thus also be maintained. In addition, the width a is smaller than the width x of the middle part 62 . The width b is smaller than the width y of the front end portion 63 .

In particular, in this embodiment, the opening area of the discharge port 73 at the position facing the intermediate portion 62 of the compression mechanism 30 gradually narrows toward the position facing the fixed portion 61 of the compression mechanism 30 . Therefore, the sealing length f between the discharge port 73 and the piston 32 can be ensured, and the discharge port 73 can be enlarged. When the cylinder 31 is flattened, the thickness of the piston 32 becomes thin. However, according to the present embodiment, the area of the opening region of the discharge port 73 can be optimized while avoiding structural constraints.

Specifically, the opening area of the discharge port 73 has a shape in which two circles having different diameters are connected by two lines having tangent points on both sides of the two circles. The larger circle of these two circles is located at a position facing the front end portion 63 of the compression mechanism 30 , and the smaller circle is located at a position opposing the middle portion 62 of the compression mechanism 30 .

In the present embodiment, a part of the opening area of the discharge port 73 has a shape that is curved in an arc shape that is concentric with the inner circumference 78 when the piston 32 is in the rotational position where the space 72 of the compression mechanism 30 as a whole becomes the suction chamber. shape. That is, one of the two lines is an arc concentric with the inner periphery 78 of the piston 32 when the piston 32 is in a rotational position where the entire space 72 of the compression mechanism 30 becomes the suction chamber. In addition, as shown in FIG. 5 , when the piston 32 is at a rotational position where the entire space 72 of the compression mechanism 30 serves as a suction chamber, the entire vane 33 is accommodated in the vane groove 77 .

In the present embodiment, another part of the opening area of the discharge port 73 has an arc shape concentric with the circumference of the fastening hole 81 . That is, the other of the above-mentioned two lines is an arc concentric with the circumference of the fastening hole 81 .

In the two bearings of the main bearing 34 and the sub bearing 35, the fastening hole 81 must be arranged outside the inner circumference 75 of the cylinder 31 and avoid the suction port 71, the vane groove 77, and the valve groove including the discharge port 73. 82 positions. And it is necessary to ensure that each bearing and the cylinder body 31 are connected by the fastening of the main bearing 34 and the cylinder body 31 on the top, the fastening of the upper cylinder body 31 and the lower cylinder body 31, and the fastening of the lower cylinder body 31 and the auxiliary bearing 35. of tightness. Therefore, the fastening holes 81 are preferably arranged at equal intervals. In addition, the farther the fastening position is from the inner periphery 75 of the cylinder 31 , the more it is necessary to enlarge the outer diameter of the bearing and increase the thickness of the flange of the bearing, thereby increasing the manufacturing cost. Therefore, the fastening hole 81 is preferably provided as close as possible to the inner periphery 75 of the cylinder 31 .

In this embodiment, even if the fastening hole 81 is arranged so as to satisfy all the above-mentioned requirements, the sealing length f with the piston 32 can be ensured without interfering with the fastening hole 81, and it is possible to provide an opening area in each bearing. The area is the discharge port 73 having an optimum area. That is, the discharge port 73 can be arranged so as to satisfy all of the above-mentioned condition 1, condition 2, and condition 3.

Specifically, as shown in FIG. 5 , the discharge port 73 can be arranged between the circumference of one fastening hole 81 and the inner circumference 78 of the piston 32 when the entire space 72 of the compression mechanism 30 is in the rotation position of the suction chamber. One side of the opening area of the discharge port 73 is kept at a certain interval from the circumference of the adjacent fastening hole 81 and is curved along the circumference of the adjacent fastening hole 81 . The other side of the opening area is kept at a constant distance from the inner circumference 78 of the piston 32 when the entire space 72 of the compression mechanism 30 becomes the suction chamber, and is curved along the inner circumference 78 of the piston 32 . Therefore, even if the fastening hole 81 is provided in the vicinity of the inner periphery 75 of the cylinder 31, the interference between the discharge port 73 and the fastening hole 81 can be avoided, so that the sealing length f between the discharge port 73 and the piston 32 can be ensured, and the discharge port can be sufficiently obtained. 73 opening area.

As shown in FIG. 6, with respect to the inner diameter D of the cylinder 31, the inner diameter d of the piston 32, and the eccentricity e, the amount g of the discharge port 73 acting on the inner side of the inner circumference 75 of the cylinder 31 needs to satisfy g≤ The condition of D/2-(e+d/2). This condition is a condition for securing the sealing length f between the discharge port 73 and the piston 32 . Satisfying this condition prevents the high-pressure refrigerant from flowing into the low-pressure space inside the inner periphery 78 of the piston 32 .

Action Description

Referring to FIG. 3 , the operation of the compressor 12 as a device of the present embodiment will be described. The operation of the compressor 12 corresponds to the refrigerant compression method of this embodiment.

Electric power is supplied from the terminal 24 to the stator 41 of the motor 40 via lead wires. As a result, current flows through the coil 44 of the stator 41 to generate magnetic flux from the coil 44 . The rotor 42 of the motor 40 is rotated by the magnetic flux generated from the coil 44 and the magnetic flux generated from the permanent magnet of the rotor 42 . As the rotor 42 rotates, the crankshaft 50 fixed to the rotor 42 rotates. As the crankshaft 50 rotates, the piston 32 of the compression mechanism 30 rotates eccentrically in the cylinder chamber 76 of the cylinder 31 of the compression mechanism 30 . The space 72 between the cylinder 31 and the piston 32 is divided into a suction chamber and a compression chamber by the vane 33 of the compression mechanism 30 . As the crankshaft 50 rotates, the volume of the suction chamber and the volume of the compression chamber change. In the suction chamber, since the volume gradually expands, low-pressure gas refrigerant is sucked in from the suction muffler 23 . In the compression chamber, the gas refrigerant in it is compressed due to the gradual reduction in volume. The compressed high-pressure and high-temperature gas refrigerant is discharged from the discharge muffler 36 to the space in the airtight container 20 . The discharged gas refrigerant further passes through the motor 40 and is discharged to the outside of the airtight container 20 from the discharge pipe 22 at the top of the airtight container 20 . The refrigerant discharged into the airtight container 20 passes through the refrigerant circuit 11 and returns to the suction muffler 23 again.

Although not shown, when the compressor 12 is configured as a swing type rotary compressor, the vane 33 and the piston 32 are integrally provided. When the crankshaft 50 is driven, the vane 33 moves in and out along the receiving groove rotatably attached to the support body of the piston 32 . The vane 33 advances and retreats in the radial direction while swinging as the piston 32 rotates, and divides the inside of the cylinder chamber 76 into a compression chamber and a suction chamber. The support body is composed of two columnar members with a semicircular cross-section. The support body is rotatably fitted in a circular holding hole formed between the suction port 71 and the discharge port 73 of the cylinder 31 .

Effect description

In this embodiment, since the discharge port 73 formed in the compression mechanism 30 is formed in such a size that it is closed not only by the front end portion 63 of the discharge valve 60 but also by the middle portion 62 of the discharge valve 60 , the compressor 12 can be realized. large capacity. The discharge port 73 is closed by the middle portion 62 of the discharge valve 60 , and the concentration of stress on the neck 65 of the discharge valve 60 and the increase of impact stress when the discharge valve 60 is seated can be suppressed, so that the discharge valve 60 is hardly damaged. Therefore, the reliability of the compressor 12 can be maintained. And since the width of the opening area of the discharge port 73 is reduced at the position closed by the intermediate portion 62 of the discharge valve 60 , the sealing length f between the discharge port 73 and the piston 32 can be ensured. The effectiveness of the compressor 12 can thus also be maintained.

In the present embodiment, the discharge port 73 having a shape connecting two circles is formed to extend toward the fixed portion 61 of the discharge valve 60 . Therefore, the area of the discharge valve 60 subjected to the pressure of the discharged refrigerant increases on the fixed portion 61 side compared to the circular discharge port. Therefore, the discharge valve 60 can be raised smoothly, and stress concentration on the neck portion 65 due to the rigidity difference between the intermediate portion 62 and the front end portion 63 of the discharge valve 60 can be reduced. In addition, the circumference of the discharge port 73 is longer than that of a circular discharge port. Therefore, when the discharge valve 60 is seated, the contact area of the discharge valve 60 with the peripheral wall portion 74 of the discharge port 73 is increased, and the impact stress can also be reduced.

In the present embodiment, the entire discharge port 73 extends along the inner circumference 75 of the cylinder 31 to a position corresponding to the middle portion 62 of the discharge valve 60 . Therefore, even in the compression mechanism 30 housed in the airtight container 20 with a small diameter, the cylinder 31 is flattened, and the eccentricity of the piston 32 is increased, the area of the discharge port 73 can be easily ensured. The performance of the compressor 12 is thus improved.

Other composition

The opening area formed in the discharge port 73 of the compression mechanism 30 may also have a shape in which, instead of two circles having different diameters, an arbitrary first figure and a second figure other than a circle are used for both the first figure and the second figure. A shape formed by joining two lines at a tangent point. The size of the first graphic is set to be different from the size of the second graphic. The first figure and the second figure may be polygons or other shapes. The shape of the discharge valve 60 is appropriately changed in accordance with the shape of the discharge port 73 so that the discharge port 73 can be closed.

Embodiment 2

Regarding this embodiment, differences from Embodiment 1 will be mainly described.

The compression mechanism 30 will be described in detail with reference to FIG. 7 .

FIG. 7 corresponds to FIG. 5 .

As in Embodiment 1, the opening region formed in the discharge port 73 of the compression mechanism 30 has a shape in which two circles with different diameters are connected by two lines having tangent points on both sides of the two circles. Of these two circles, the larger circle is at a position facing the front end portion 63 of the compression mechanism 30 , and the smaller circle is at a position facing the middle portion 62 of the compression mechanism 30 .

In this embodiment, the above two lines are tangents of the above two circles.

In this embodiment, as shown in FIG. 7 , the discharge port 73 can also be arranged on the circumference of one fastening hole 81 , and the inner circumference 78 when the space 72 of the compression mechanism 30 with the piston 32 as a whole becomes the rotation position of the suction chamber. between. One side of the opening area of the discharge port 73 extends linearly away from the circumference of the adjacent fastening hole 81 . The other side of the opening area extends linearly away from the inner periphery 78 of the piston 32 when the entire space 72 of the compression mechanism 30 is in the rotational position of the suction chamber. Therefore, even if the fastening hole 81 is provided near the inner periphery 75 of the cylinder 31, the discharge port 73 can be avoided from interfering with the fastening hole 81, and the sealing length f with the piston 32 can be ensured. However, it is also possible to obtain a sufficient opening area of the discharge port 73 .

The embodiments of the present invention have been described above, but some of the above-described embodiments may be implemented in combination. Alternatively, any one or several of the foregoing implementation manners may also be partially implemented. Specifically, only any one of the parts described as "parts" in the description of the above-mentioned embodiment may be used, or an arbitrary combination of several parts may be used. In addition, this invention is not limited to the said embodiment, Various changes are possible as needed.

Claims (8)

1. A compressor, characterized in that, possesses: a compression mechanism formed with a space for compressing refrigerant, and a discharge port for discharging refrigerant compressed in the space; and A discharge valve comprising a fixed portion, a front end portion fixed to the compression mechanism, and a middle portion, the front end portion closing the discharge port freely, and the middle portion closing the discharge port. The fixing part is connected to the front end, and together with the front end, closes the discharge port openably and closably, A width of an opening area of the discharge port at a position opposing the intermediate portion of the compression mechanism is smaller than an opening area of the discharge port at a position opposing the front end of the compression mechanism. width. 2. The compressor of claim 1, wherein: An opening area of the discharge port at a position of the compression mechanism facing the intermediate portion gradually narrows toward a position of the compression mechanism facing the fixing portion. 3. The compressor of claim 1, wherein: The opening area of the discharge port has a shape in which two circles having different diameters are connected by two lines having tangent points on both sides of the two circles. 4. The compressor of claim 1, wherein: The compression mechanism includes: a ring-shaped piston forming the space at a position outside the outer circumference of the piston, and the piston rotates eccentrically; The space is divided into a low-pressure suction chamber and a high-pressure compression chamber, A part of the opening area of the discharge port has a shape curved concentrically with the inner circumference of the piston when the piston is at a rotational position where the entire space becomes the suction chamber. 5. The compressor of claim 4, wherein: The opening area of the discharge port has a shape in which two circles having different diameters are connected by two lines having tangent points on both sides of the two circles, one of the two lines is An arc concentric with the inner periphery of the piston when the entire space is at a rotational position of the suction chamber. 6. The compressor of claim 4, wherein: The compression mechanism further includes: a cylinder forming the space on the inner side of the inner circumference of the cylinder; a bearing forming the discharge port and a circular fastening hole and inserted into the fastening Fasteners with fixed holes are fixed to the cylinder to support the rotation shaft of the piston, Another part of the opening area of the discharge port has an arc shape concentric with the circumference of the fastening hole. 7. The compressor of claim 6, wherein: The opening area of the discharge port has a shape in which two circles having different diameters are connected by two lines having tangent points on both sides of the two circles, one of the two lines is The other of the two lines is a circular arc concentric with the circumference of the fastening hole. 8. A refrigeration cycle device, characterized in that, A refrigerant circuit is provided, and the refrigerant circuit is connected to the compressor according to any one of claims 1 to 7, and the refrigerant is circulated.