JP2014040815A - Rotary compressor - Google Patents

Abstract

A rotary compressor capable of maintaining a good sliding state of a roller while securing an injection amount of a refrigerant having an intermediate pressure.
A rotary compressor includes a crankshaft, a cylinder, a rear head, a front head, and a piston including a roller and a blade. The rear head 60 is formed with an injection flow path 61a through which intermediate pressure refrigerant from the outside flows into the compression chamber S1. The first end surface 81a of the roller 80 includes a first wide surface 81a1 having a partially increased radial width. The outlet opening 61a1 of the injection flow path 61a is blocked by the first wide surface 81a1 when the revolution angle of the roller 80 is within a predetermined range. The second end surface 82a of the roller 80 includes a second wide surface 82a1. The second wide surface 82a1 is at the same position as the first wide surface 81a1 in plan view.
[Selection] Figure 2

Description

  The present invention relates to a rotary compressor, and more particularly to a rotary compressor into which an intermediate pressure refrigerant is introduced from the outside.

  Conventionally, in a refrigerant circuit of a refrigeration apparatus, an intermediate-pressure refrigerant may be injected into a compression chamber of a compressor. For example, in the refrigerant circuit of an air conditioner disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 11-13664), a gas-liquid separator located between an outdoor heat exchanger and an indoor heat exchanger is changed to a compressor. The injection tube extends toward the end. Then, an injection operation is performed in a predetermined operation state, and an intermediate-pressure refrigerant is injected (introduced) into the compression chamber through an injection hole of the rear head attached to the lower end surface of the cylinder of the compressor.

  In the rotary compressor disclosed in Patent Document 1 above, the lower end of the roller body is arranged so that the injection hole having a large cross-sectional area in order to ensure the injection amount does not communicate with the high-pressure space inside the roller. A seal plate portion protruding inward from the inner surface of the portion is provided. The lower surface of the seal plate portion and the lower surface of the roller main body are continuous, and even when a part of the injection hole is located inside the inner peripheral surface of the roller main body, the injection hole is formed between the roller main body and the seal plate portion. It is blocked by both lower surfaces.

  However, if the seal plate portion is provided at one end portion of the roller body in this way, the weight balance with the other end portion of the roller body is lost. Since the weight of the seal plate portion is small, it is normal that the problem does not occur so much, but the inventor of the present application uses both ends of the roller when using a refrigerant whose operating temperature is higher than the conventional one. It has been found that a small difference in weight worsens the sliding state between the roller and the front head, and worsens the supply state of lubricating oil from the oil supply path inside the shaft to each sliding surface of the roller.

  The subject of this invention is providing the rotary compressor which can maintain the sliding state of a roller favorable, ensuring the injection amount of the refrigerant | coolant of intermediate pressure.

  The rotary compressor according to the first aspect of the present invention is a compressor that sucks in a low-pressure refrigerant, compresses the pressure to increase the pressure of the refrigerant, and discharges the high-pressure refrigerant. The rotary compressor includes a rotating shaft, a cylinder, a first cylinder head, a second cylinder head, a roller that revolves as the shaft rotates, and a blade. The cylinder has an open first end, and also opens a second end opposite to the first end. The first cylinder head closes the opening at the first end of the cylinder. The second cylinder head closes the opening at the second end of the cylinder. The roller is disposed in the internal space of the cylinder, and an annular first end surface thereof is in contact with the first cylinder head. An annular second end surface opposite to the first end surface of the roller is in contact with the second cylinder head. The blade partitions the inner space of the cylinder together with the outer peripheral surface of the roller, and forms a compression chamber whose volume changes according to the revolution of the roller. Further, the first cylinder head is formed with an injection flow path for flowing an intermediate-pressure refrigerant introduced from the outside into the compression chamber. The annular first end surface of the roller includes a first wide surface having a partially increased radial width. The outlet opening of the injection flow path is blocked by the first wide surface of the first end surface of the roller when the revolution angle of the roller is within a predetermined range. The annular second end surface of the roller includes a second wide surface. The second wide surface is a portion of the second end surface where the radial width is partially increased, and is located at the same position as the first wide surface of the first end surface when viewed in the rotational axis direction of the shaft.

  Here, since the first end surface of the roller includes the first wide surface, even when the outlet opening of the injection flow path is enlarged or the outlet opening is relatively moved closer to the rotation shaft side of the shaft, the first wide surface is also provided. The surface blocks the outlet opening, and the outlet opening is prevented from communicating with the high-pressure space inside the first end surface of the roller. In addition, the second wide surface of the second end surface is disposed at the same plane position as the first wide surface of the annular first end surface of the roller when viewed in the rotational axis direction of the shaft. That is, a first wide surface having a partially large radial width is formed on the first end surface of the roller, and a similar second wide surface is formed on the second end surface of the roller opposite to the first end surface. doing. For this reason, the weight balance along the rotation axis of the shaft between the first end face side portion and the second end face side portion of the roller is improved. Thereby, the rotation balance during the operation of the compressor is improved, and the sliding state of the roller can be kept good while securing the injection amount of the intermediate pressure refrigerant by the injection flow path.

  The rotary compressor which concerns on the 2nd viewpoint of this invention is a rotary compressor which concerns on a 1st viewpoint, Comprising: As for a roller, the 1st end part in which the 1st end surface is formed, and the 2nd end surface are formed. A second end portion and a central portion located between the first end portion and the second end portion; The central part has a cylindrical shape. The first end portion and the second end portion each have a main body portion and a protruding portion. The main body portion has a cylindrical shape, and the outer diameter thereof is the same as the outer diameter of the central portion. The protruding portion protrudes inward from the main body portion. Moreover, the internal diameter of the main-body part of a 1st end part and a 2nd end part is larger than the internal diameter of a center part. The inner surfaces of the projecting portions of the first end portion and the second end portion overlap with the inner peripheral surface of the central portion or are located on the outer side of the inner peripheral surface of the central portion when viewed in the rotational axis direction of the shaft. The protruding portion of the first end portion and a part of the main body portion of the first end portion located outside the protruding portion form a first wide surface. Moreover, the protrusion part of a 2nd end part and a part of main-body part of the 2nd end part located in the outward of a protrusion part form the 2nd wide surface.

  Here, the roller has a first end, a second end, and a central portion, and is formed such that the inner diameter of the main body portion of the first end portion and the second end portion is larger than the inner diameter of the central portion. Yes. And the inner surface of the protrusion part of a 1st end part and a 2nd end part overlaps with the internal peripheral surface of a center part, or is located outside the internal peripheral surface of a center part. That is, the first end portion and the second end portion do not include a portion protruding inward from the inner peripheral surface of the central portion, and it is easy to pass the shaft through the roller. For this reason, the assembly man-hour at the time of assembling the rotary compressor which a roller revolves by rotation of a shaft can be reduced, and manufacturing cost can be suppressed.

  A rotary compressor according to a third aspect of the present invention is the rotary compressor according to the first aspect or the second aspect, wherein the outlet opening of the injection flow path is the first end face of the roller as viewed in the rotational axis direction of the shaft. A predetermined seal dimension is ensured between the outlet opening of the injection flow path and the inner edge of the first end surface of the roller at the revolution angle of the roller approaching the inner edge.

  Here, even when the outlet opening of the injection flow channel is closest to the inner edge of the first end surface of the roller, a predetermined seal dimension is secured between the outlet opening of the injection flow channel and the inner edge of the first end surface of the roller. Therefore, there is almost no communication between the outlet opening of the injection flow path and the high-pressure space inside the first end surface of the roller.

  In the rotary compressor according to the fourth aspect of the present invention, in the rotary compressor according to any one of the first aspect to the third aspect, the roller and the blade are integral.

  Here, since the roller and the blade are integrated, there is no friction between the two members and gas leakage from the gap, and the operation efficiency and durability are improved.

  In the rotary compressor according to the first aspect of the present invention, the first wide surface is formed on the first end surface of the roller, and the same second wide surface is formed on the second end surface opposite to the first end surface. Therefore, the rotation balance of the roller during the operation of the compressor is improved, and the sliding state of the roller can be kept good while securing the injection amount of the intermediate pressure refrigerant by the injection flow path.

  In the rotary compressor according to the second aspect of the present invention, the number of assembling steps can be reduced and the manufacturing cost can be suppressed.

  In the rotary compressor according to the third aspect of the present invention, there is almost no communication between the outlet opening of the injection flow path and the high-pressure space inside the first end face of the roller.

  In the rotary compressor according to the fourth aspect of the present invention, the operation efficiency and durability are improved.

The longitudinal cross-sectional view of the rotary compressor which concerns on one Embodiment of this invention. The longitudinal cross-sectional schematic diagram of a compression mechanism. The figure which looked at the cylinder and the piston from the lower part. The figure which looked at the piston which consists of a roller and a blade from the downward direction. The injection flow path when the piston roller is positioned at the revolution angle at which the high-pressure refrigerant is discharged from the compression chamber to the muffler chamber through the front head discharge hole and the low-pressure refrigerant is sucked into the compression chamber from the suction hole of the cylinder. The figure which shows the relative position of an exit opening and the 1st wide surface of the 1st end surface of a roller. The relative relationship between the outlet opening of the injection flow path and the first wide surface of the first end surface of the roller when the roller of the piston is positioned at the revolution angle immediately before the suction of the low-pressure refrigerant from the suction hole of the cylinder to the compression chamber ends The figure which shows a position. When the piston roller is positioned at the revolution angle at which the low-pressure refrigerant in the compression chamber starts to be compressed and the injection of the intermediate-pressure refrigerant from the injection flow channel begins, the first wide opening at the outlet of the injection flow channel and the first end surface of the roller The figure which shows a relative position with a surface. When the piston roller is positioned at the revolution angle at which the refrigerant is compressed in the compression chamber and the intermediate pressure refrigerant is injected from the injection flow path, the first wide end of the first opening of the roller and the outlet opening of the injection flow path The figure which shows a relative position with a surface. When the piston roller is positioned at the revolution angle at which the injection of the high-pressure refrigerant from the compression chamber to the muffler chamber through the front head discharge hole is finished, The figure which shows the relative position of an exit opening and the 1st wide surface of the 1st end surface of a roller.

(1) Overall Configuration As shown in FIG. 1, the rotary compressor 10 is a one-cylinder rotary compressor, and includes a casing 11, a drive mechanism 20 and a compression mechanism 30 disposed in the casing 11. ing. In the rotary compressor 10, the compression mechanism 30 is disposed below the drive mechanism 20 in the casing 11.

  The rotary compressor 10 is a device used for compressing R32 refrigerant in a refrigeration apparatus such as an air conditioner or a heat pump type hot water heater. The rotary compressor 10 sucks the refrigerant from the accumulator 95 of the refrigeration apparatus, compresses it, and compresses it at high temperature and high pressure. The refrigerant having been discharged is discharged from the discharge pipe 25 toward the gas cooler of the refrigeration apparatus.

  Further, the rotary compressor 10 has a function of receiving an intermediate-pressure refrigerant supplied from an injection circuit of a refrigeration apparatus into a compression chamber S1 (described later) of the compression mechanism 30.

(2) Detailed Configuration (2-1) Drive Mechanism The drive mechanism 20 is housed in the upper part of the internal space of the casing 11 and drives the compression mechanism 30. The drive mechanism 20 includes a motor 21 serving as a drive source and a crankshaft 22 that is a drive shaft attached to the motor 21.

  The motor 21 is a motor for rotating the crankshaft 22, and mainly includes a rotor 23 and a stator 24. The rotor 23 has a crankshaft 22 inserted in its internal space, and rotates together with the crankshaft 22. The rotor 23 is composed of laminated electromagnetic steel plates and a magnet embedded in the rotor body. The stator 24 is disposed outside the rotor 23 in the radial direction via a predetermined space. The stator 24 includes laminated electromagnetic steel plates and a coil wound around the stator body. The motor 21 rotates the rotor 23 together with the crankshaft 22 by electromagnetic force generated in the stator 24 by passing an electric current through the coil.

  The crankshaft 22 is inserted into the rotor 23 and rotates around the rotation axis CA shown in FIG. Further, as shown in FIGS. 2 and 3, the crank pin 22 a that is an eccentric portion of the crankshaft 22 is inserted into a roller 80 (described later) of the piston 31 of the compression mechanism 30, and the rotational force from the rotor 23. Is fitted to the roller 80 in a state where it can be transmitted. The crankshaft 22 rotates according to the rotation of the rotor 23, rotates the crankpin 22a eccentrically, and revolves the roller 80 of the piston 31 of the compression mechanism 30. That is, the crankshaft 22 has a function of transmitting the driving force of the motor 21 to the compression mechanism 30.

  As shown by a dotted line in FIG. 2, an oil flow path is formed in the crankshaft 22 to guide the oil accumulated in the lower part of the internal space of the casing 11 upward.

(2-2) Compression Mechanism The compression mechanism 30 is accommodated on the lower side in the casing 11. The compression mechanism 30 compresses the refrigerant sucked from the accumulator 95 through the suction pipe 96. The compression mechanism 30 is a rotary type compression mechanism, and mainly includes a front head 40, a cylinder 50, a piston 31, and a rear head 60. Further, the refrigerant compressed in the compression chamber S1 of the compression mechanism 30 passes through the muffler space S2 surrounded by the front head 40 and the muffler 70 from the front head discharge hole 41a formed in the front head 40, and then the motor 21 It is discharged into the space where the lower end of the discharge pipe 25 is located.

(2-2-1) Cylinder The cylinder 50 is a metal casting member. The cylinder 50 includes a cylindrical center part 50a, a first extension part 50b extending from the center part 50a toward the accumulator 95, and a second extension part 50c extending from the center part 50a to the opposite side of the first extension part 50b. Have. The first outer extension 50b is formed with a suction hole 51 for sucking low-pressure refrigerant in the refrigeration cycle. A cylindrical space inside the inner peripheral surface 50a1 of the central portion 50a serves as a cylinder chamber 52 into which the refrigerant sucked from the suction hole 51 flows. The suction hole 51 extends from the cylinder chamber 52 toward the outer peripheral surface of the first outer extending portion 50b, and is opened on the outer peripheral surface of the first outer extending portion 50b. Into the suction hole 51, the distal end portion of the suction pipe 96 extending from the accumulator 95 is inserted. The cylinder chamber 52 accommodates a piston 31 and the like for compressing the refrigerant flowing into the cylinder chamber 52.

  The cylinder chamber 52 formed by the cylindrical central portion 50a of the cylinder 50 has a first end that is a lower end thereof and a second end that is an upper end thereof. The first end, which is the lower end of the central portion 50a, is closed by a rear head 60 described later. The second end, which is the upper end of the central portion 50a, is closed by the front head 40 described later.

  Further, the cylinder 50 is formed with a blade swing space 53 in which a bush 35 and a blade 90 described later are disposed. The blade swing space 53 is formed across the central portion 50a and the first outer extension portion 50b, and the blade 90 of the piston 31 is supported by the cylinder 50 via the bush 35 so as to be swingable. The blade swing space 53 is formed so as to extend from the cylinder chamber 52 toward the outer peripheral side in the vicinity of the suction hole 51 in a plan view.

(2-2-2) Front Head As shown in FIGS. 1 and 2, the front head 40 includes a front head disk portion 41 that closes the opening of the second end that is the upper end of the cylinder 50, and the front head disk. A front head boss portion 42 extending upward from the periphery of the front head opening at the center of the portion 41. The front head boss portion 42 has a cylindrical shape and functions as a bearing for the crankshaft 22.

  The front head disc portion 41 is formed with a front head discharge hole 41a at a planar position shown in FIG. The refrigerant compressed in the compression chamber S1 whose volume changes in the cylinder chamber 52 of the cylinder 50 is intermittently discharged from the front head discharge hole 41a. The front head disc portion 41 is provided with a discharge valve that opens and closes the outlet of the front head discharge hole 41a. This discharge valve opens due to a pressure difference when the pressure in the compression chamber S1 becomes higher than the pressure in the muffler space S2, and discharges the refrigerant from the front head discharge hole 41a to the muffler space S2.

(2-2-3) Muffler The muffler 70 is attached to the upper surface of the peripheral part of the front head disk part 41 of the front head 40, as shown in FIG. The muffler 70 forms a muffler space S2 together with the upper surface of the front head disc portion 41 and the outer peripheral surface of the front head boss portion 42 to reduce noise associated with refrigerant discharge. As described above, the muffler space S2 and the compression chamber S1 communicate with each other through the front head discharge hole 41a when the discharge valve is open.

  Further, the muffler 70 is formed with a central muffler opening through which the front head boss portion 42 penetrates, and a muffler discharge hole through which a refrigerant flows from the muffler space S2 to the accommodation space of the motor 21 above.

  The muffler space S2, the accommodation space for the motor 21, the space above the motor 21 where the discharge pipe 25 is located, the space where the lubricating oil is accumulated below the compression mechanism 30, and the like are all connected, and the high pressure is equal. A space is formed.

(2-2-4) Rear Head The rear head 60 is a rear head disk portion 61 that closes the opening of the first end, which is the lower end of the cylinder 50, and a bearing that extends downward from the peripheral edge portion of the central opening of the rear head disk portion 61. Rear head boss part 62. The front head disc portion 41, the rear head disc portion 61, and the central portion 50a of the cylinder 50 form a cylinder chamber 52 as shown in FIG. The front head boss portion 42 and the rear head boss portion 62 are cylindrical boss portions and support the crankshaft 22.

  An injection flow path 61 a is formed in the rear head disc portion 61. The injection flow path 61a is connected to an injection hole (not shown) opened in the casing 11, and is connected to a refrigerant pipe of an injection circuit of the refrigeration apparatus. The injection flow path 61 a extends horizontally from the injection hole of the casing 11 toward the rotation axis CA of the crankshaft 22, bends upward in the middle, and opens on the upper surface of the rear head disc portion 61. The outlet opening 61a1 of the injection flow path 61a opens at a planar position indicated by a two-dot chain line in FIG. That is, the outlet opening 61a1 of the injection flow path 61a opens to the cylinder chamber 52 inside the inner peripheral surface 50a1 of the central portion 50a of the cylinder 50. This injection flow path 61a allows intermediate pressure refrigerant introduced from the outside of the rotary compressor 10 to enter the compression chamber S1 whose volume changes in the cylinder chamber 52 when the revolution angle of the roller 80 of the piston 31 is within a certain range. Play a role. Accordingly, when the revolution angle of the roller 80 of the piston 31 is in a predetermined range other than the above-described fixed range, the roller 31 is blocked by the first wide surface 81a1 (described later).

(2-2-5) Piston The piston 31 is disposed in the cylinder chamber 52 and is attached to a crank pin 22 a that is an eccentric portion of the crankshaft 22. As shown in FIGS. 2 to 4, the piston 31 is a member in which a roller 80 and a blade 90 are integrated. The blade 90 of the piston 31 is disposed in the blade swing space 53 formed in the cylinder 50 and is supported by the cylinder 50 via the bush 35 so as to be swingable as described above. Further, the blade 90 is slidable with the bush 35, and swings and repeats the movement away from the crankshaft 22 or approaching the crankshaft 22 during operation.

  The roller 80 includes a first end portion 81 on which a first end surface 81a that is a roller lower end surface is formed, a second end portion 82 on which a second end surface 82a that is a roller upper end surface is formed, and the first ends thereof. The center part 83 is located between the part 81 and the second end part 82. As shown in FIG. 4, the central portion 83 is a cylindrical portion having an inner diameter D2 and an outer diameter D1. The first end portion 81 includes a cylindrical first main body portion 81b having an inner diameter D3 and an outer diameter D1, and a first protrusion portion 81c that protrudes inward from the first main body portion 81b. The outer diameter D1 of the first main body portion 81b is the same as the outer diameter D1 of the central portion 83. Further, the inner diameter D3 of the first main body portion 81b is larger than the inner diameter D2 of the central portion 83. The second end portion 82 includes a cylindrical second main body portion 82b having an inner diameter D3 and an outer diameter D1, and a second protruding portion 82c protruding inward from the second main body portion 82b. The outer diameter D1 of the second main body portion 82b is the same as the outer diameter D1 of the central portion 83, like the outer diameter D1 of the first main body portion 81b. The inner diameter D3 of the second main body portion 82b is the same as the inner diameter D3 of the first main body portion 81b, and is larger than the inner diameter D2 of the central portion 83. The inner surface 81c1 of the first projecting portion 81c and the inner surface 82c1 of the second projecting portion 82c substantially overlap the inner peripheral surface 83a1 of the central portion 83 when viewed in the direction of the rotation axis of the crankshaft 22. Specifically, the inner surface 81c1 of the first projecting portion 81c and the inner surface 82c1 of the second projecting portion 82c are located slightly outside the inner peripheral surface 83a1 of the central portion 83 in plan view. As described above, since the inner diameter D3 of the first main body portion 81b and the second main body portion 82b is larger than the inner diameter D2 of the central portion 83 except for the first protruding portion 81c and the second protruding portion 82c, the first A first step surface 83a2 is formed at the height position of the boundary between the end portion 81 and the center portion 83, and a second step surface 83a3 is formed at the height position of the boundary between the second end portion 82 and the center portion 83. (See FIGS. 2 and 4).

  An annular first end surface 81 a of the first end portion 81 of the roller 80 is in contact with the upper surface of the rear head disc portion 61 and slides with the upper surface of the rear head disc portion 61. The first end surface 81a of the roller 80 includes a first wide surface 81a1 having a partially increased radial width. The first protruding portion 81c of the first end portion 81 and a part of the first main body portion 81b of the first end portion 81 located on the outer side thereof form a first wide surface 81a1 (see FIG. 4). ).

  An annular second end surface 82 a of the second end portion 82 of the roller 80 is in contact with the lower surface of the front head disc portion 41 and slides with the lower surface of the front head disc portion 41. The second end surface 82a of the roller 80 includes a second wide surface 82a1 having a partially increased radial width. The second wide surface 82a1 is located at the same position as the first wide surface 81a1 when the crankshaft 22 is viewed in the rotational axis direction. The second projecting portion 82c of the second end portion 82 and a part of the second main body portion 82b of the second end portion 82 located on the outer side thereof form a second wide surface 82a1.

  As shown in FIGS. 2 and 3, the roller 80 and the blade 90 of the piston 31 form a compression chamber S <b> 1 that partitions the cylinder chamber 52 and whose volume changes as the piston 31 revolves. The compression chamber S1 is a space surrounded by the inner peripheral surface 50a1 of the central portion 50a of the cylinder 50, the upper surface of the rear head disc portion 61, the lower surface of the front head disc portion 41, and the piston 31. As shown in FIGS. 3 and 5 to 9, the volume of the compression chamber S <b> 1 changes according to the revolution of the piston 31, and the low-pressure refrigerant sucked from the suction hole 51 is compressed to become a high-pressure refrigerant. 41a is discharged into the muffler space S2.

When the rotation angle of the piston 31 shown in FIGS. 3 and 4 is viewed in the rotational axis direction of the crankshaft 22, the outlet opening 61a1 of the injection flow path 61a opened on the upper surface of the rear head disc portion 61 is It is closest to the inner edge 81d of the first end surface 81a, which is the lower end surface of the roller 80. At this revolution angle, a predetermined seal dimension t0 ′ is secured between the outlet opening 61a1 of the injection flow path 61a and the inner edge 81d of the first end surface 81a of the roller 80. At this revolution angle, the center of the outlet opening 61a1 of the injection flow passage 61a is located at the inside of the outer edge of the first end surface 81a of the roller 80 by a dimension l, and the diameter of the first protrusion 81c of the first end surface 81a. The width t in the direction is
Formula: t = 1 + (D / 2) + t0 ′
It becomes the dimension expressed by. D is the diameter of the outlet opening 61a1. The radial width t0 of the first end surface 81a excluding the first wide surface 81a1 is:
Formula: t0 = (D1-D3) / 2
It is the dimension represented by.

(3) Operation In the rotary compressor 10, the refrigerant compressed in the compression chamber S1 whose volume is changed by the movement of the piston 31 of the compression mechanism 30 revolving by the eccentric rotation of the crank pin 22a is transferred from the compression chamber S1 to the front head discharge hole. It is guided to the muffler space S2 through 41a. The refrigerant introduced into the muffler space S2 is discharged from the muffler discharge hole of the muffler 70 to a space above the muffler space S2. The refrigerant discharged to the outside of the muffler space S2 passes through the space between the rotor 23 and the stator 24 of the motor 21, cools the motor 21, and then is discharged from the discharge pipe 25 to the high-pressure refrigerant pipe of the refrigeration apparatus. Is done.

  Next, the compression of the refrigerant in the compression chamber S1 will be described in detail.

  While the piston 31 gradually moves from the revolution angle shown in FIG. 8 to the revolution angle shown in FIGS. 9, 3, and 5, low-pressure refrigerant is sucked into the compression chamber S1 from the suction hole 51. The compression chamber S1 facing the suction hole 51 gradually increases in volume when the refrigerant is sucked. When the piston 31 moves from the revolution angle shown in FIG. 6 to the revolution angle shown in FIG. 7, the communication state between the compression chamber S1 and the suction hole 51 is canceled, and refrigerant compression in the compression chamber S1 starts. When the piston 31 has the revolution angle shown in FIG. 8, a medium-pressure refrigerant is injected from the outlet opening 61a1 of the injection flow passage 61a into the compression chamber S1. Thereafter, when the piston 31 reaches the revolution angle shown in FIG. 9, the volume of the compression chamber S1 that is in communication with the front head discharge hole 41a becomes considerably small, and the pressure of the refrigerant also becomes high. 9, the first wide surface 81a1 of the first end surface 81a of the roller 80 of the piston 31 blocks the outlet opening 61a1 of the injection flow path 61a of the rear head disc portion 61, and the intermediate pressure is reduced. The refrigerant is not injected into the compression chamber S1. Thereafter, when the piston 31 has the revolution angle shown in FIGS. 3 and 5, the high-pressure refrigerant pushes the discharge valve from the front head discharge hole 41a and is discharged into the muffler space S2.

(4) Features (4-1)
In the rotary compressor 10 according to the present embodiment, as shown in FIG. 2, the space inside the roller 80 of the piston 31 is such that the space between the inner peripheral surface 83a1 of the roller 80 and the crank pin 22a is the sliding portion of the compression mechanism 30. A high-pressure space is provided in which lubricating oil is supplied to each sliding portion from an oil passage in the crankshaft 22. If this high pressure space communicates with the injection flow path 61a, intermediate pressure injection may be hindered, or high pressure oil may flow backward and flow into the refrigerant piping of the refrigeration apparatus.

  However, in the rotary compressor 10, since the first end surface 81a of the roller 80 of the piston 31 includes the first wide surface 81a1, the diameter D of the outlet opening 61a1 of the injection flow path 61a is increased and the outlet opening 61a1 is cranked. Regardless of the configuration approaching the shaft 22 side, the outlet opening 61a1 is reliably closed by the first wide surface 81a1 (see FIGS. 3 to 6).

  Thereby, it is suppressed that the injection flow path 61a of the rear head 60 communicating with the injection circuit through which the intermediate pressure refrigerant of the refrigeration apparatus flows communicates with the high-pressure space inside the roller 80 of the piston 31.

  In addition, the second wide surface 82a1 of the second end surface 82a is disposed at the same position as the first wide surface 81a1 of the annular first end surface 81a of the roller 80 when viewed from the rotation axis direction of the crankshaft 22. That is, the first wide end surface 81a1 having a partly large radial width is formed on the first end surface 81a of the roller 80, and the second end surface 82a of the roller 80 opposite to the first end surface 81a is similar. A second wide surface 82a1 is formed. Therefore, the weight balance between the first end portion 81 on the first end surface 81a side of the roller 80 and the second end portion 82 on the second end surface 82a side is improved. As a result, the rotational balance during operation of the rotary compressor 10 is improved, and the sliding state of the roller 80 of the piston 31 can be kept good while ensuring the injection amount of the intermediate pressure refrigerant by the injection flow path 61a. ing.

(4-2)
In the rotary compressor 10, the roller 80 of the piston 31 has a first end portion 81, a second end portion 82, and a central portion 83, and the main body portions 81 b and 82 b of the first end portion 81 and the second end portion 82. The roller 80 is formed so that the inner diameter D3 is larger than the inner diameter D2 of the central portion 83. The inner surfaces 81c1 and 82c1 of the projecting portions 81c and 82c of the first end portion 81 and the second end portion 82 substantially overlap the inner peripheral surface 83a1 of the center portion 83 when viewed in the direction of the rotation axis of the crankshaft 22. Specifically, the inner surface 81c1 of the first projecting portion 81c and the inner surface 82c1 of the second projecting portion 82c are located slightly outside the inner peripheral surface 83a1 of the central portion 83 in plan view.

  That is, the first end portion 81 and the second end portion 82 do not include a portion projecting inward from the inner peripheral surface 83a1 of the central portion 83, and the crank pin 22a of the crankshaft 22 can be passed through the roller 80. Easy. For this reason, the assembly man-hour at the time of assembling the rotary compressor 10 in which the piston 31 revolves by the eccentric rotation of the crank pin 22a is reduced, and the manufacturing cost is also reduced.

(4-3)
As shown in FIG. 4, in the rotary compressor 10, even when the outlet opening 61a1 of the injection flow path 61a is closest to the inner edge 81d of the first end surface 81a of the roller 80, the outlet opening 61a1 and the inner edge 81d of the roller 80 are Since a predetermined seal dimension t0 ′ is ensured during the period, there is almost no communication between the outlet opening 61a1 of the injection flow path 61a and the high-pressure space inside the roller 80.

  The predetermined seal dimension t0 'is a dimension determined based on set values such as the refrigerant pressure of the refrigeration apparatus supplied to the injection flow path 61a and the pressure of the space inside the roller 80.

(4-4)
The rotary compressor 10 does not combine the roller 80 and the blade 90 as separate members but uses a piston 31 in which these are integrated. For this reason, when it is set as a separate member, both the friction and the gas leakage from a clearance are lost, and the driving efficiency and durability are improved.

(4-5)
In the rotary compressor 10, the roller 80 of the piston 31 includes a first end portion 81, a second end portion 82, and a central portion 83, and the first excluding the first projecting portion 81 c and the second projecting portion 82 c. The end portion 81 and the second end portion 82 are molded by scraping the inner peripheral portion. As described above, since the upper and lower end portions 81 and 82 are partially scraped, the sliding loss between the roller 80 of the piston 31, the rear head 60 and the front head 40 is reduced. Further, by cutting part of the upper and lower end portions 81 and 82, the lubricating oil from the oil flow path of the crankshaft 22 enters the space, and the necessary lubricating oil is reliably secured in the compression mechanism 30. ing.

(5) Modification (5-1) Modification A
In the above embodiment, the injection flow path 61a is formed not in the front head 40 but in the rear head disc portion 61 of the rear head 60. Instead, an intermediate pressure refrigerant is provided in the front head disc portion 41 of the front head 40. It is also possible to form an injection flow path for supplying the liquid.

(5-2) Modification B
In the above-described embodiment, the present invention is applied to the one-cylinder rotary compressor 10, but the present invention can also be applied to a two-cylinder rotary compressor. In this case, a middle head is provided in addition to the front head and the rear head, but the injection flow path may be formed in any head.

DESCRIPTION OF SYMBOLS 10 Rotary compressor 22 Crankshaft 30 Compression mechanism 31 Piston 40 Front head (2nd cylinder head)
50 cylinders 60 rear head (first cylinder head)
61a Injection channel 61a1 Outlet opening of injection channel 80 Roller 81 First end 81a First end surface 81a1 First wide surface 81b First body portion 81c First protrusion 81c1 Inner surface of first protrusion 81d Inner edge of first end surface 82 2nd end part 82a 2nd end surface 82a1 2nd wide surface 82b 2nd main-body part 82c 2nd protrusion part 82c1 Inner surface of the 2nd protrusion part 83 Central part 83a1 Inner peripheral surface of the center part 90 Blade S1 Compression chamber D Injection flow path The diameter of the outlet opening D1 The outer diameter of the first body portion, the second body portion, and the center portion D2 The inner diameter of the center portion D3 The inner diameter of the first body portion and the second body portion t0 ′ Predetermined seal size

Japanese Patent Laid-Open No. 11-13664

Claims (4)

A rotary compressor (10) for sucking and compressing a low-pressure refrigerant to increase the pressure of the refrigerant and discharging the high-pressure refrigerant,
A rotating shaft (22);
A cylinder (50) having an open first end and a second end opposite the first end;
A first cylinder head (60) for closing the opening at the first end of the cylinder;
A second cylinder head (40) for closing the opening at the second end of the cylinder;
The inside of the cylinder has an annular first end surface (81a) in contact with the first cylinder head, and an annular second end surface (82a) opposite to the first end surface in contact with the second cylinder head. A roller (80) disposed in space and revolved by rotation of the shaft;
A blade (90) that partitions the internal space of the cylinder together with the outer peripheral surface (80a) of the roller and forms a compression chamber (S1) whose volume changes in accordance with the revolution of the roller;
With
The first cylinder head is formed with an injection flow path (61a) for flowing an intermediate-pressure refrigerant introduced from the outside into the compression chamber,
The annular first end surface (81a) of the roller includes a first wide surface (81a1) having a partially increased radial width,
The outlet opening (61a1) of the injection flow path is blocked by the first wide surface (81a1) of the first end surface of the roller when the revolution angle of the roller is within a predetermined range,
The annular second end surface (82a) of the roller has a partially larger radial width at the same position as the first wide surface (81a1) of the first end surface in the rotational axis direction of the shaft. A second wide surface (82a1) that is
Rotary compressor. The roller (80) includes a first end (81) where the first end surface (81a) is formed, a second end (82) where the second end surface (82a) is formed, A central portion (83) located between the first end and the second end,
The central portion (83) has a cylindrical shape,
The first end portion (81) and the second end portion (82) are respectively cylindrical main body portions (81b, 82b) having the same outer diameter (D1) as the central portion, and inward from the main body portion. Projecting portions (81c, 82c) projecting,
The inner diameter (D3) of the main body is larger than the inner diameter (D2) of the central portion,
The inner surface (81c1) of the protruding portion overlaps with the inner peripheral surface (83a1) of the central portion when viewed in the rotation axis direction of the shaft, or is positioned outside the inner peripheral surface of the central portion,
A part of the first end portion (81) and the projecting portion (81c) and the body portion (81b) located outside the projecting portion form the first wide surface (81a1). ,
The protruding portion (82c) of the second end portion (82) and a part of the main body portion (82b) located outside the protruding portion form the second wide surface (82a1). ,
The rotary compressor according to claim 1. The injection flow when the outlet opening (61a1) of the injection flow path is closest to the inner edge (81d) of the first end surface (81a) of the roller as viewed in the rotational axis direction of the shaft. A predetermined seal dimension (t0 ′) is secured between the outlet opening (61a1) of the road and the inner edge (81d) of the first end surface of the roller.
The rotary compressor according to claim 1 or 2. The roller (80) and the blade (90) are integral.
The rotary compressor in any one of Claim 1 to 3.