JP2012154235A - Rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary compressor that reduces power loss to be caused by a change in compression volume during capacity adjustment by controlling compression of refrigerant gas before the intake of the refrigerant gas is cut off.SOLUTION: The rotary compressor includes a cylinder 5, a shaft 4 having an eccentric part, a piston 9 which is fitted to an eccentric part of the shaft 4 and revolves in a cylinder chamber 6, a vane 11 which partitions the cylinder chamber 6 into an intake chamber 12 with an opened intake port 17 and a compression chamber 13, and a vane groove 10 which is formed in the cylinder 5 and includes the reciprocating vane 11. A tip of the vane 11 is rockably fitted and connected to the piston 9. A refrigerant gas releasing means for moving the suction cut-off position of refrigerant gas to be sucked from the intake port 17 to the compression chamber 13 side is provided to control the compression of the refrigerant gas. Thus, the power loss caused by the change in the compression volume during the capacity adjustment can be reduced thereby.

Description

  The present invention relates to a rotary compressor that can be incorporated into a refrigerator and an air conditioner.

  In general, this type of rotary compressor has a predetermined compression capacity depending on the model. To increase or decrease the capacity, a cylinder with the same size is combined with a piston with a different eccentric amount and a piston with a different outer diameter. The ability is adjusted. However, in this case, the cylinders can be shared, but the types of shafts and pistons increase, so the management of parts becomes complicated, and it is necessary to change the manufacturing assembly line, which increases costs. It was.

  Therefore, conventionally, as described in Japanese Patent Application Laid-Open No. 58-70089, one of a cylinder, a main bearing, and a sub-bearing is connected to a bypass that communicates the compression chamber and the suction chamber in the refrigerant gas compression stroke. A method is known in which a groove is provided and the capacity is adjusted by changing the length of the groove. As shown in FIGS. 6 and 7, this capacity adjustment method includes a sealed container 1 in which an electric motor unit and a compression mechanism unit driven by the electric motor unit are housed. The compression mechanism unit includes a cylinder 5 and the cylinder. 5, a main bearing 7 and a sub-bearing 8 which are fastened to both end surfaces to form a cylinder chamber 6, a shaft 4 provided with an eccentric portion between the main bearing 7 and the sub-bearing 8, and an eccentric portion of the shaft 4. It is composed of a piston 9 that revolves in the cylinder chamber 6 and a vane 11 that reciprocates in a vane groove 10 formed in the radial direction of the cylinder 5, and the tip of the vane 11 is the outer periphery of the piston 9. In a rotary compressor configured to form a suction chamber 12 and a compression chamber 13 partitioned by a vane 11 in a cylinder chamber 6 in contact with a surface, a cylinder 5, a main bearing 7 and a sub-compression To one of receiving 8, is provided with a suction closed-away position of the refrigerant gas sucked from the suction port 17, the bypass channel X of the refrigerant gas is moved to the compression chamber 13 side. Thus, when the contact point 201 where the outer peripheral surface of the piston 9 revolving in the cylinder chamber 6 with the rotation of the shaft 4 comes into contact with the inner peripheral surface of the cylinder 5 is located in the bypass groove X, the suction chamber 12 is compressed. The chamber 13 is in a communicating state, the refrigerant gas sucked from the suction port 17 is not closed, and after passing through the bypass groove X, the suction of the refrigerant gas is closed and the compression chamber 13 becomes a sealed space. Is compressed by the volume change to become high temperature and high pressure, and is discharged from the compression chamber 13 through the discharge port 18 and the discharge muffler chamber 19 into the sealed container 1. Therefore, by changing the length of the bypass groove for the refrigerant gas provided in one of the cylinder, the main bearing, and the sub-bearing, the closing position of the refrigerant gas sucked from the suction port can be arbitrarily set to the compression chamber side. The capacity is adjusted by changing the compression volume.

JP 58-70089 A

However, in the rotary compressor shown in FIGS. 6 and 7, the oil in the oil reservoir at the bottom of the sealed container is sucked by the oil pump provided in the shaft 4 and compressed through the hollow hole provided in the shaft 4. Since the sliding surface in the mechanism portion is lubricated and lubricated, the piston is rotated with the rotation of the shaft 4 due to the viscosity of the oil present in the sliding surface between the eccentric portion of the shaft 4 and the inner peripheral surface of the piston 9. 9 rotates in the rotation direction of the shaft 4, and therefore, when the bypass groove X is located at the contact point 201 and the suction chamber 12 and the compression chamber 13 communicate with each other, the suction chamber is formed on the outer peripheral surface and the end surface of the piston 9. The viscous flow of the refrigerant gas from 12 to the compression chamber 13 is induced to inhibit the flow of the refrigerant gas passing through the bypass groove X, and the refrigerant gas is pressurized before the contact point 201 passes through the bypass groove X. There is a problem to start. That is, the refrigerant gas in the compression chamber 13 that started compression before the suction of the refrigerant gas is completely closed passes through the bypass groove X and leaks to the suction chamber 12 side, so that a relatively large power loss has occurred.

  Further, in the vicinity of the suction port 17 provided in the cylinder 5, fastening bolts for fastening the main bearing 7 and the sub-bearing 8 are located on both end faces of the cylinder 5, so that a bypass provided on the inner peripheral surface of the cylinder 5. The depth of the groove X is limited, and even when the bypass groove X is provided in the main bearing 7 and the sub-bearing 8, if the end plates of the main bearing 7 and the sub-bearing 8 are thickened, the material cost increases, so the cylinder The depth of the bypass groove X is also limited within a range in which the deformation in the chamber 6 is allowed.

  The present invention solves the problems of the prior art, and reduces the viscous flow of refrigerant gas from the suction chamber to the compression chamber induced on the outer peripheral surface and end surface of the piston before the refrigerant gas suction is completely closed. An object of the present invention is to provide a rotary compressor that suppresses the compression of refrigerant gas and has a small power loss that occurs when adjusting the capacity by changing the compression volume.

  In order to solve the problems of the prior art, a rotary compressor according to the present invention includes a cylinder, a main bearing and a sub-bearing that are fastened to both end surfaces of the cylinder to form a cylinder chamber, and a main bearing and a sub-bearing. A shaft provided with an eccentric portion therebetween, a piston fitted into the eccentric portion of the shaft and revolving within the cylinder chamber, a vane dividing the cylinder chamber into a suction chamber having a suction port and a compression chamber, and a cylinder are formed. The vane has a vane groove in which the vane reciprocates, and the tip end portion of the vane is swingably fitted and connected to the piston. The suction gas closing position of the refrigerant gas sucked from the suction port is set to the compression chamber side. It is characterized in that a means for escaping the refrigerant gas to be moved is provided.

  According to the above, the viscous flow of the refrigerant gas from the suction chamber to the compression chamber induced by the outer peripheral surface and the end surface of the piston is reduced, and the compression of the refrigerant gas before the refrigerant gas suction is completely closed is suppressed. Therefore, it is possible to provide a rotary compressor with a small power loss that occurs when adjusting the capacity by changing the compression volume.

The longitudinal cross-sectional view which shows the rotary compressor in Example 1 of this invention 1 is a cross-sectional view showing a compression mechanism portion of a rotary compressor in Embodiment 1 of the present invention. The expanded perspective view which shows the cylinder of the rotary compressor in Example 1 of this invention. (A)-(D) The schematic diagram for demonstrating operation | movement of the rotary compressor in Example 1 of this invention. The expansion perspective view which shows the cylinder of the rotary compressor in Example 2 of this invention. Longitudinal sectional view showing a conventional rotary compressor Cross-sectional view showing a compression mechanism of a conventional rotary compressor

A first invention includes a cylinder, a main bearing and a sub-bearing that are fastened to both end surfaces of the cylinder to form a cylinder chamber, a shaft having an eccentric portion between the main bearing and the sub-bearing, and an eccentric portion of the shaft And a piston that revolves in the cylinder chamber, a vane that divides the cylinder chamber into a suction chamber in which a suction port opens and a compression chamber, and a vane groove that is formed in the cylinder and reciprocally moves the vane. In a rotary compressor configured such that the tip portion is slidably fitted and connected to a piston, a refrigerant gas escape means for moving the suction closed position of the refrigerant gas sucked from the suction port to the compression chamber side is provided. It is provided. As a result, since the tip end of the vane is slidably fitted and connected to the piston, the rotation of the piston that revolves in the cylinder chamber as the shaft rotates can be limited by the vane. Therefore, the refrigerant gas escape means for moving the suction closed position of the refrigerant gas sucked from the suction port to the compression chamber side is located at a contact point where the outer peripheral surface of the piston is in contact with the inner peripheral surface of the cylinder. Reducing the viscous flow of refrigerant gas from the suction chamber to the compression chamber induced on the outer peripheral surface and end surface of the piston when the chamber and the compression chamber are in communication, before the refrigerant gas suction is completely closed, By suppressing the compression of the refrigerant gas, it is possible to reduce power loss that occurs during capacity adjustment due to a change in the compression volume.

  According to a second aspect of the invention, in the rotary compressor of the first aspect of the invention, as the escape means, a notch extending in the rotational direction of the shaft is provided on the inner peripheral surface of the cylinder so as to communicate with the suction port. is there. Therefore, end milling and T-slots are applied to the inner peripheral surface of the cylinder with relatively low hardness and good workability without adding processing to the piston that requires high hardness due to severe sliding with the tip of the vane. The effect of 1st invention can be acquired by providing a notch by cutter processing.

  According to a third aspect of the invention, in the rotary compressor of the second aspect of the invention, the notch provided as the escape means is open to the end surfaces of the main bearing and the sub-bearing over the entire thickness direction of the cylinder. It is what. As a result, the suction port can be opened in the notch regardless of the location in the thickness direction of the cylinder, the main bearing, or the sub-bearing.

  According to a fourth aspect of the invention, in the rotary compressor of the second aspect of the invention, the notch provided as the escape means is limited to only an intermediate portion in the thickness direction of the cylinder, and is provided at end faces of the main bearing and the sub-bearing. On the other hand, it is blocked. As a result, a predetermined thickness can be secured on the end surface of the cylinder in the thickness direction, so that the machining resistance can be made substantially uniform over the entire inner peripheral surface during precision machining of the inner peripheral surface of the cylinder. A roundness can be secured. Therefore, since the gap formed between the outer peripheral surface of the piston that revolves in the cylinder chamber and the inner peripheral surface of the cylinder can be reduced, leakage of refrigerant gas that has started compression from the compression chamber to the suction chamber is reduced. The effects of the second invention can be obtained without reducing the volumetric efficiency.

  In the fifth aspect of the invention, in particular, in the rotary compressor according to any one of the second to fourth aspects of the invention, the end of the notch provided as the escape means is the cylinder at the time when the vane is most housed in the vane groove. Of the intersections between the inner peripheral surface and the vane thickness direction center line, a point closer to the vane is used as a base point, and is configured within a range of 90 degrees in the rotation direction of the shaft. As a result, when the outer peripheral surface of the piston faces the notch provided on the inner peripheral surface of the cylinder, the piston always rotates in the direction opposite to the rotation of the shaft, so that the suction from the compression chamber induced on the outer peripheral surface of the piston. By promoting the flow of the refrigerant gas passing through the notch using the viscous flow of the refrigerant gas to the chamber, the power loss can be reduced more effectively.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of a single-stage compression rotary compressor 100 having one compression mechanism 101 as an embodiment of the rotary compressor of the present invention, and FIG. 2 is a transverse sectional view of the compression mechanism 101. ing.

A rotary compressor 100 shown in FIG. 1 is arranged in a cylindrical hermetic container 1, an electric motor unit 102 disposed on the upper side inside the hermetic container 1, and a lower side of the electric motor unit 102. And the bottom of the closed container 1 is used as an oil reservoir.

  The electric motor unit 102 includes a stator 2 that is annularly attached along the inner peripheral surface on the inner upper side of the sealed container 1, and a rotor 3 that is inserted with a slight gap inside the stator 2. The rotor 3 is fixed to the shaft 4 in the vertical direction at the center.

  As shown in FIGS. 1 and 2, the compression mechanism unit 101 includes a cylinder 5, a main bearing 7 and a sub-bearing 8 that are fastened to both end surfaces of the cylinder 5 to form a cylinder chamber 6, and the main bearing 7. A piston 9 fitted to an eccentric portion of the shaft 4 positioned between the auxiliary bearing 8 and a vane 11 reciprocating in a vane groove 10 formed in the radial direction of the cylinder 5 is provided. The suction chamber 12 and the compression chamber 13 partitioned by the vane 11 are formed in the cylinder chamber 6 by swinging and connecting to a fitting portion formed on the piston 9 in a circular arc shape. .

  The cylinder 5 of the rotary compressor according to this embodiment configured as described above will be described with reference to FIG. FIG. 3 is an enlarged perspective view showing the cylinder 5 of the rotary compressor according to the first embodiment of the present invention. As shown in FIG. 3, the inner peripheral surface of the cylinder 5 is provided with a notch Y that communicates with the suction port 17 and extends in the rotational direction of the shaft 4. And open to the end face of the secondary bearing 8. Further, the end portion of the notch Y is the intersection of the inner peripheral surface of the cylinder 5 and the center line in the thickness direction of the vane 11 when the vane 11 is most accommodated in the vane groove 10, which is closer to the vane 11. As a base point, it is configured within a range of up to 90 degrees in the rotation direction of the shaft 4. The reason for providing this angle range will be described with reference to FIG.

  FIG. 4 is a schematic diagram illustrating the operation of the rotary compressor according to the first embodiment of the present invention. As shown in FIG. 4, the positional relationship between the piston 9 and the vane 11 when the piston 9 is revolved by 90 degrees is shown in the order of FIGS. 4 (A), (B), (C), (D). Yes. 4A, 4B, 4C, and 4D, refrigerant gas is sucked from a suction port 17 provided in the cylinder 5, and the outer peripheral surface of the piston 9 that revolves in the cylinder chamber 6 is While the contact point 201 in contact with the inner peripheral surface of the cylinder 5 is located in the notch Y, the suctioned refrigerant gas is not closed while the suction chamber 12 and the compression chamber 13 are in communication with each other. After the passage, the suction of the refrigerant gas is closed and the compression chamber 13 becomes a sealed space, and the refrigerant gas is compressed by the volume change due to the revolving motion of the piston 9 and the reciprocating motion of the vane 11 to become high temperature and high pressure. ) Is discharged into the sealed container 1 from the compression chamber 13 through a discharge port 18 and a discharge muffler chamber 19 (not shown). That is, by moving the suction closed position of the refrigerant gas sucked from the suction port 17 to the compression chamber 13 side by the notch Y provided on the inner peripheral surface of the cylinder 5, the compression volume at the suction closed position is increased. Change and adjust your abilities.

During the revolution movement of the piston 9 from the state of FIG. 4A to the state of FIG. 4C, the tip end portion of the vane 11 is slidably fitted and connected to the piston 9. 4 returns to the same angular position as in FIG. 4 (A) in the state of FIG. 4 (C) while swinging in the cylinder chamber 6 around the tip of the vane 11. Therefore, during the revolution movement of the piston 9, the rotation angle of the piston 9 becomes smaller than that of the prior art rotary compressor in which the piston 9 rotates in the rotation direction of the shaft 4, and the peripheral speed on the outer peripheral surface of the piston 9 is reduced. Therefore, the flow of the refrigerant gas induced on the outer peripheral surface of the piston 9 can be reduced. In particular, during the revolution movement of the piston 9 from the state of FIG. 4A to the state of FIG. 4B, the piston 9 rotates in the opposite direction to the rotation of the shaft 4 as the shaft 4 rotates. A viscous flow of refrigerant gas from the compression chamber 13 to the suction chamber 12 is induced on the outer peripheral surface of the piston 9. Therefore, since this viscous flow can be utilized, the refrigerant gas is compressed before the suction of the refrigerant gas is closed by promoting the flow of the refrigerant gas passing through the notch Y provided on the inner peripheral surface of the cylinder 5. Since the power loss can be reduced more effectively by suppressing, the end portion of the notch Y is formed in this angular range.

  With the above configuration, in this embodiment, the tip of the vane 11 is slidably fitted and connected to the piston 9, and the notch Y provided on the inner peripheral surface of the cylinder 5 is the entire thickness direction of the cylinder 5. The end of the notch Y is open to the end surfaces of the main bearing 7 and the sub-bearing 8, and the end of the notch Y and the inner peripheral surface of the cylinder 5 when the vane 11 is most accommodated in the vane groove 10 Of the intersections with the center line in the thickness direction, the compression chamber is induced on the outer peripheral surface of the piston 9 because it is configured within a range of up to 90 degrees in the rotation direction of the shaft 4 with the one closer to the vane 11 as the base point. Before the suction of the refrigerant gas is closed, the viscous flow of the refrigerant gas from the suction chamber 13 to the suction chamber 12 is utilized to promote the flow of the refrigerant gas passing through the notch Y provided on the inner peripheral surface of the cylinder 5. Suppresses refrigerant gas compression Te, the power loss occurring at the time of capacity adjustment by variation of compression volume it is possible to provide a small rotary compressor.

(Embodiment 2)
Next, FIG. 5 shows another embodiment of the present invention. As shown in FIG. 5, the inner peripheral surface of the cylinder 5 is provided with a notch Y that communicates with the suction port 17 and extends in the rotational direction of the shaft 4, and is limited to only the middle portion in the thickness direction of the cylinder 5. The end surfaces of the main bearing 7 and the sub-bearing 8 are closed, and a predetermined thickness can be secured on the end surface in the thickness direction of the cylinder 5, so that the machining resistance is reduced when the inner peripheral surface of the cylinder 5 is precisely machined. It can be made substantially uniform over the entire circumference, and the roundness of the inner circumferential surface of the cylinder 5 can be secured. Accordingly, the gap formed between the outer peripheral surface of the piston 9 that revolves in the cylinder chamber 6 and the inner peripheral surface of the cylinder 5 can be reduced, so that the compressed refrigerant gas from the compression chamber 13 to the suction chamber 12 can be compressed. The same effects as those of the first embodiment can be obtained without reducing leakage to the volume and lowering the volumetric efficiency.

  As described above, since the rotary compressor according to the present invention can reduce power loss, it can be applied to a hot water compressor and an air compression application.

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Stator 3 Rotor 4 Shaft 5 Cylinder 6 Cylinder chamber 7 Main bearing 8 Sub bearing 9 Piston 10 Vane groove 11 Vane 12 Suction chamber 13 Compression chamber 17 Suction port 18 Discharge port 19 Discharge muffler chamber 100 Rotary compressor 101 Compression Mechanism part 102 Electric motor part 201 Contact point X Bypass groove Y Notch

Claims (5)

A cylinder,
A main bearing and a sub-bearing fastened to both end faces of the cylinder to form a cylinder chamber, a shaft provided with an eccentric portion between the main bearing and the sub-bearing, and fitted to the eccentric portion of the shaft; A piston that revolves in the cylinder chamber; a vane that divides the cylinder chamber into a suction chamber in which a suction port opens; and a compression chamber; and a vane groove that is formed in the cylinder and reciprocates in the vane. It is a rotary compressor configured by fitting and connecting a tip portion with the piston in a swingable manner,
A rotary compressor having a refrigerant gas escape means for moving a refrigerant gas suction closed position from the suction port to the compression chamber side. 2. The rotary compressor according to claim 1, wherein as the escape means, a notch that communicates with the suction port and extends in a rotation direction of the shaft is provided on an inner peripheral surface of the cylinder. 3. The rotary compressor according to claim 2, wherein the notch provided as the escape means extends over the entire thickness direction of the cylinder and is open to the end surfaces of the main bearing and the auxiliary bearing. . The notch provided as the escape means is limited to only an intermediate portion in the thickness direction of the cylinder, and is closed with respect to end faces of the main bearing and the sub-bearing. Rotary compressor. The end portion of the notch provided as the escape means is close to the vane at the intersection of the inner peripheral surface of the cylinder and the center line in the thickness direction of the vane when the vane is most housed in the vane groove. The rotary compressor according to any one of claims 2 to 4, wherein the rotary compressor is configured within a range of up to 90 degrees in a rotation direction of the shaft with the direction as a base point.

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