JP2009150304A - Hermetic compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hermetic compressor constructed to suppress the flow of high-pressure operating fluid in a storage space into a suction chamber via a clearance between the upper end face of a roller and a front head and one between the lower end face of the roller and a rear head. <P>SOLUTION: In a region on the side of a suction part where there is a great difference between pressure in a sealed container and pressure in a cylinder chamber, the width of a seal face 210 of the roller 20 for a rotary piston 10 is greater than in a region on the side of a discharge part. This suppresses the flow of the high-pressure operating fluid in the storage space of the sealed container into the suction chamber via the clearance between the upper end face of the roller 20 and the front head and the one between the lower end face of the roller 20 and the rear head. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hermetic compressor, and more particularly to an improvement in the structure of a hermetic compressor.

<Overall configuration of hermetic compressor>
With reference to FIG. 16 and FIG. 17, the whole structure of a rotary compressor is demonstrated as an example of a hermetic compressor. 16 is a longitudinal sectional view showing the overall configuration of the rotary compressor, and FIG. 17 is a sectional view taken along line XVII-XVII in FIG. The rotary compressor has a casing 1, and the casing 1 is hermetically sealed by closing an upper end opening of a cylindrical intermediate cylinder 2 by an upper lid 3 and closing a lower end opening by a lower lid 4. It is configured in a sealed structure. A suction pipe 5 for introducing a working fluid as a refrigerant into the casing 1 is connected to the lower end side of the intermediate cylinder 2, and a discharge pipe for discharging the high-pressure working fluid compressed in the casing 1 to the outside is connected to the upper lid 3. 6 is connected.

  A compression element 7 for sucking and compressing gas is disposed on the lower end side of the casing 1 in correspondence with the suction pipe 5, and a drive element 8 for operating the compression element 7 is disposed almost above the entire interior space. It is arranged to occupy. In the internal space defined by the lower lid 4 at the lower end portion of the casing 1, an oil reservoir 9 for storing the lubricating oil O is formed, and in other spaces, a storage space 10 for storing the compressed gas is formed. .

<Compression element 7>
The compression element 7 has a cylinder 12 having a cylinder chamber 11 having a circular cross-sectional shape, and a front head 13 having a boss-like bearing portion 13a at the center on both the upper and lower surfaces of the cylinder 12 and a boss at the center. The cylinder head 11 is hermetically sealed by fastening a plurality of bolts 15 to the rear head 14 having a cylindrical bearing portion 14a.

  The peripheral edge of the cylinder 12 is fixed to the inner wall surface of the intermediate cylinder 2 of the casing 1 and is supported in the casing 1 in a horizontal state. The muffler member 16 is fixed to the front head 13 so as to provide an annular gap around the bearing portion 13 a of the front head 13 with the muffler member 16.

  A suction pipe 120 is provided in the cylinder 12, and the suction pipe 5 and the cylinder chamber 11 communicate with each other by inserting the suction pipe 5 into the suction pipe 120. A discharge port 12b is formed on the side of the suction pipe 120 of the cylinder 12, and the discharge port 12b communicates with a recess 12c formed on the back side thereof. The recess 12c is a through hole formed in the front head 13. It communicates with the storage space 10 (not shown). As a result, the cylinder chamber 11 communicates with the storage space 10.

  A leaf spring-like discharge valve 17 is disposed in the recess 12c so as to be supported by a pin 18 so that the discharge port 12b can be opened and closed, and prevents the compressed gas discharged into the storage space 10 from flowing back into the cylinder chamber 11.

  A rotating piston 19 is disposed in the cylinder chamber 11 of the cylinder 12. The rotary piston 19 includes an annular roller 20 having a circular insertion hole 20a, and a rectangular plate-like blade 21 integrally projecting radially outward on the side wall of the roller 20. The roller 20 is eccentrically arranged in the cylinder chamber 11 by a crankshaft 26 described later.

  A blade sliding groove 12d extending outward in the cylinder radial direction is provided between the suction pipe 120 of the cylinder 12 and the discharge port 12b, and a cylindrical shape (as a whole) is formed at an intermediate portion of the blade sliding groove 12d. The planar shape is a shape in which the upper and lower end portions of a substantially perfect circle shape are cut off), and a bush hole 12e that bulges outward from both sides of the blade sliding groove 12d is formed. In this bush hole 12e, two substantially semi-cylindrical block-shaped blade bushes 22 that constitute a rotation clamping body are disposed so as to be rotatable around a rotation center Q. The blade 21 of the rotary piston 19 is sandwiched so as to be slidable in the cylinder radial direction from both sides by the blade bush 22 while being inserted into the blade sliding groove 12d. It swings around Q.

<Drive element 8>
The drive element 8 includes an electric motor including a stator 24 and a rotor 25, and the stator 24 is fixedly supported on the inner wall surface of the intermediate cylinder 2 of the casing 1. The rotor 25 is arranged concentrically inside the stator 24 with a predetermined gap in the circumferential direction. The upper half portion of the crankshaft 26 is rotatably integrated around the shaft center P inside the rotor 25, and the lower half portion of the crankshaft 26 is rotatable to both bearing portions 13a and 14a of the front head 13 and the rear head 14. It is inserted and supported.

  An oil passage 26 a extending in the axial direction is formed in the crankshaft 26, and a centrifugal oil pump 27 is attached to the lower end of the crankshaft 26. The oil pump 27 is constantly immersed in the lubricating oil O of the oil reservoir 9, sucks the lubricating oil O into the oil passage 26 a according to the rotation of the crankshaft 26, and supplies it to the sliding portions of the compression element 7 and the driving element 8. It is like that.

  An eccentric shaft portion 26 b is provided near the lower end of the crankshaft 26. The eccentric shaft portion 26b is positioned in the cylinder chamber 11 and is inserted into the insertion hole 20a of the roller 20 of the rotary piston 19 so as to rotate together. Accordingly, the roller 20 rotates eccentrically in the cylinder chamber 11 by the rotation of the crankshaft 26 around the axis P. The cylinder chamber 11 is divided into a suction chamber 11a and a compression chamber 11b by a blade 21.

  The volumes of the suction chamber 11a and the compression chamber 11b gradually change due to the eccentric rotational movement of the roller 20, and when the roller 20 is at the top dead center position that simultaneously closes the suction port 120 and the discharge port 12b, When the entire cylinder chamber 11 becomes the suction chamber 11a and the roller 20 is at the position of the bottom dead center 180 ° opposite to the cylinder chamber 11, the volume of the suction chamber 11a and the compression chamber 11b is equalized with the blade 21 as a boundary. It has become.

  The thus configured rotary compressor is used, for example, to compress refrigerant gas in a refrigerant circuit of an air conditioner. In this case, the refrigerant gas is sucked into the suction chamber 11a of the cylinder chamber 11 through the suction pipe 5 from the evaporator. The sucked refrigerant gas is compressed in the compression chamber 11b as the roller 20 rotates eccentrically. The refrigerant gas in a high pressure state is discharged from the discharge port 12b to the storage space 10 through a gap between the bearing portion 13a of the front head 13 and the muffler member 16, and further discharged to the condenser through the discharge pipe 6. The

  During this time, in the compression chamber 11b, the refrigerant gas is compressed in a mixed gas state in which the lubricating oil O is mixed. Therefore, the lubricating oil O is scattered in the mist state in the storage space 10, and the lubricating oil O in the mist state is It is separated from the refrigerant gas and collected in the oil sump 9. Examples of the rotary compressor having such a configuration include those described in Patent Documents 1 to 4 below.

  Here, with reference to FIG. 18, the pressure relationship of the working fluid in the compression element 7 is demonstrated. 18 is a cross-sectional view corresponding to the arrow XVII-XVII in FIG. 16, and is a schematic diagram in which the cross-sectional structure shown in FIG. 17 is simplified. In the state shown in FIG. 18, the rotary piston 19 (roller 20) is located at the bottom dead center, and the working fluid is sucked into the suction chamber 11a of the cylinder chamber 11 from the suction pipe 5 and compressed in the compression chamber 11b. The fluid is discharged from the discharge port 12b to the storage space 10. In this state, the suction chamber 11a is in a low pressure state, the storage space 10 and the inner side of the roller 20 are in a high pressure state, and the compression chamber 11b is in a high pressure state.

  Therefore, since the compression chamber 11b, the storage space 10, and the roller 20 are all in a high pressure state, the differential pressure in each region is small. On the other hand, since the suction chamber 11a is in a low pressure state, the differential pressure between the suction chamber 11a and the storage space 10 and between the suction chamber 11a and the inside of the roller 20 is large.

  Further, since the rotary piston 19 in the compression element 7 is rotating, there is a slight gap between the upper end surface of the roller 20 and the front head 13 and between the lower end surface of the roller 20 and the rear head 14. Is required. However, as described above, the differential pressure between the suction chamber 11a and the storage space 10 and between the suction chamber 11a and the inside of the roller 20 is large, and the width of the seal surface of the roller 20 of the rotary piston 19 is as follows. Since it is provided uniformly, the working fluid in a high-pressure state may flow into the suction chamber 11a through the gap in a region where the differential pressure is large, and the performance of the rotary compressor 1 may be reduced.

  In the state shown in FIG. 19, when the rotary piston 19 (roller 20) is located at the top dead center and the roller 20 simultaneously closes the suction port 120 and the discharge port 12b, the working fluid has an intermediate pressure. However, since the pressure of the working fluid in the storage space 10 is smaller, there is a concern that the working fluid in a high-pressure state flows into the cylinder chamber 11 through the gap.

Such a flow of the working fluid into the cylinder chamber 11 is considered to be in a higher pressure state than the conventional working fluid when using a CO ₂ refrigerant that has been attracting attention as a new working refrigerant in recent years. Therefore, there is a concern that the above-described high-pressure working fluid is likely to flow into the cylinder chamber 11.
JP 2006-37927 A JP-A-10-122171 Japanese Patent Laid-Open No. 10-122172 JP 60-128990 A

  The problem to be solved by the present invention is that the high-pressure working fluid in the storage space of the sealed container is sucked through the gap between the upper end surface of the roller and the front head and between the lower end surface of the roller and the rear head. There exists a possibility that it may flow into the chamber and reduce the performance of the hermetic compressor. Accordingly, the present invention has been made to solve the above-described problem, and the working fluid in a high-pressure state in the storage space is between the upper end surface of the roller and the front head and between the lower end surface of the roller and the rear head. Another object of the present invention is to provide a hermetic compressor having a structure capable of suppressing the flow into the suction chamber through the gap.

  In the hermetic compressor according to the present invention, the inner side of the hermetic container is inserted into the eccentric shaft portion of the crankshaft and disposed in the cylinder chamber, and is brought into the suction side by an annular rotary piston that revolves in the cylinder chamber. A hermetic compressor that houses a compression element that compresses sucked working fluid and discharges it to the discharge side, and a drive element that eccentrically rotates the rotary piston, and has the following configuration.

  The compression element includes the cylinder chamber in which the rotating piston is eccentrically rotated by having a cylinder, a front head that sandwiches the cylinder from one side, and a rear head that sandwiches the cylinder from the other side. A radial direction defined between an inner diameter and an outer diameter of a roller of the rotary piston facing the front head and the rear head in a region where the difference between the internal pressure of the sealed container and the internal pressure of the cylinder chamber is large. The width of the seal surface is set larger than the width of the seal surface in a region where the difference between the internal pressure of the sealed container and the internal pressure of the cylinder chamber is small.

  According to the hermetic compressor based on this invention, in the region where the difference between the internal pressure of the hermetic container and the internal pressure of the cylinder chamber is large, the width of the seal surface of the roller of the rotary piston becomes larger than that of the other regions. By providing as described above, the high-pressure working fluid in the storage space of the sealed container flows into the suction chamber through the gap between the upper end surface of the roller and the front head and between the lower end surface of the roller and the rear head. It is possible to suppress the decrease in the capacity of the hermetic compressor.

  Embodiments of a hermetic compressor based on the present invention will be described below with reference to the drawings. In addition, the case where this invention is applied to the rotary compressor shown in the said background art is demonstrated as an example of the hermetic compressor in this Embodiment. Since the basic configuration of the rotary compressor is the same as the structure of the rotary compressor described with reference to FIGS. 16 and 17, in the following description, the same reference numerals are used for the same or corresponding parts. In addition, the overlapping description will not be repeated, and only the characteristic components of the present invention will be described in detail below. In the description of each embodiment, a schematic diagram similar to that shown in FIG. 18 is used from the viewpoint of more clearly showing the features of the invention.

(Embodiment 1)
With reference to FIG. 1 to FIG. 3, characteristic portions of the rotary compressor in the first embodiment will be described. FIG. 1 is a cross-sectional view showing a compression element 7A employed in the rotary compressor in the first embodiment, and is a cross-sectional view corresponding to a cross section taken along line XVII-XVII in FIG. 2 is a plan view showing the shape of the rotary piston 19 employed in the rotary compressor according to Embodiment 1, and FIG. 3 is a cross-sectional view taken along the line III-III in FIG.

  In the compression element 7A of the rotary compressor in the present embodiment, the roller of the rotary piston 19 that faces the front head 13 and the rear head 14 in a region where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is large. The width of the sealing surface 210 in the radial direction defined between the inner diameter (L2) and the outer diameter (L1) of the stepped portion provided at the upper and lower end portions of the cylinder 20 depends on the internal pressure of the hermetic container 1 and the cylinder chamber 11. It is provided larger than the width of the seal surface 210 in a region where the difference from the internal pressure is small.

  Specifically, as shown in FIGS. 2 and 3, the center P11 of the outer diameter (L1) of the roller 20 is located on the imaginary line V1 where the blade 21 extends, and the upper and lower ends of the roller 20 of the rotary piston 19 The position of the center P21 of the inner diameter (L2) of the stepped portion provided in the discharge portion is a region where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is small when viewed from the position of the outer diameter center P11. It is shifted to the side.

  The center P11 of the outer diameter (L1) of the roller 20 and the center P12 of the insertion hole 20a of the roller 20 are at the same position. Thereby, the width of the seal surface 210 in the radial direction defined between the outer diameter (L1) of the roller 20 of the rotary piston 19 and the inner diameter (L2) of the stepped portion is set closer to the suction portion side than to the discharge portion side. Will be bigger.

  As described above, according to the rotary compressor in the present embodiment, the sealing surface 210 of the roller 20 of the rotary piston 19 is provided on the suction portion side where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is large. Is set to be larger than the region on the discharge unit side, so that the high-pressure working fluid in the storage space 10 of the sealed container 1 is transferred between the upper end surface of the roller 20 and the front head 13 and the roller 20. It is possible to suppress the flow into the suction chamber 11a through the gap between the lower end surface of the rear head 14 and the rear head 14, and it is possible to reduce the reduction in the capacity of the rotary compressor.

  In FIG. 2, the width of the seal surface 210 of the roller 20 of the rotary piston 19 is set to be larger on the suction portion side than on the region on the discharge portion side. Although the case where the contour of the inner diameter (L2) is circular is shown, the present invention is not limited to this configuration. As shown in FIGS. 4 to 7, the stepped portion has a polygonal seal surface 220. It is also possible to employ a seal surface 230 having a combination of a circular arc and a straight line in the stepped portion, a seal surface 240 having two types of arcs having different curvatures, and a seal surface 250 having a substantially elliptical shape.

(Embodiment 2)
Next, characteristic parts of the rotary compressor according to the second embodiment will be described with reference to FIGS. FIG. 8 is a cross-sectional view showing a compression element 7B employed in the rotary compressor in the second embodiment, and is a cross-sectional view corresponding to a cross section taken along line XVII-XVII in FIG. FIG. 9 is a plan view showing the shape of the rotary piston 19 employed in the rotary compressor in the second embodiment, and FIG. 10 is a cross-sectional view taken along line XX in FIG.

  In the compression element 7B of the rotary compressor in the present embodiment, the roller of the rotary piston 19 that faces the front head 13 and the rear head 14 in a region where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is large. The width of the seal surface in the radial direction defined between the inner diameter and the outer diameter of 20 is larger than the width of the seal surface in the region where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is small. In addition, when the center P12 of the insertion hole 20a of the roller 20 of the rotary piston 19 is viewed from the position of the center P11 of the outer diameter L1 of the roller 20, the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is small. It is shifted to the side.

  Specifically, as shown in FIGS. 9 and 10, the center P11 of the outer diameter (L1) of the roller 20 is located on the virtual line V1 where the blade 21 extends, and the center P12 of the insertion hole 20a of the roller 20 is located. However, it is shifted to the discharge part side, which is a region where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is small.

  As described above, according to the rotary compressor in the present embodiment, the seal surface 260 of the roller 20 of the rotary piston 19 is provided on the suction portion side where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is large. Is set to be larger than the region on the discharge unit side, so that the high-pressure working fluid in the storage space 10 of the sealed container 1 is transferred between the upper end surface of the roller 20 and the front head 13 and the roller 20. It is possible to suppress the flow into the suction chamber 11a through the gap between the lower end surface of the rear head 14 and the rear head 14, and it is possible to reduce the reduction in the capacity of the rotary compressor.

(Embodiment 3)
With reference to FIGS. 11 to 13, characteristic portions of the rotary compressor in the third embodiment will be described. FIG. 11 is a longitudinal sectional view showing a sectional structure of a compression element of the rotary compressor in the third embodiment, and FIG. 12 is a first-stage first employed in the rotary compressor in the third embodiment. FIG. 13 is a plan view showing the shape of a rotary piston 19U, and FIG. 13 is a plan view showing the shape of a second-stage second rotary piston 19D employed in the rotary compressor in the third embodiment.

  In the compression element 7C of the rotary compressor in the present embodiment, along the axial direction of the crankshaft 26, the first cylinder chamber 11A disposed on the front head 13 side and the second cylinder disposed on the rear head 14 side. A two-stage compression configuration having the chamber 11B is employed. Further, the area of the seal surface of the first rotary piston 19U accommodated in the first cylinder chamber 11A is provided larger than the area of the seal surface of the second rotary piston 19D accommodated in the second cylinder chamber 11B.

  Specifically, FIG. 12 shows a plan view of the first rotary piston 19U, and FIG. 13 shows a plan view of the second rotary piston 19D. The basic configuration of the first rotary piston 19U and the second rotary piston 19D in the present embodiment is the same as that of the rotary piston 19 shown in the first embodiment, and the upper and lower ends of the rollers 20 of the rotary pistons 19U and 19D. The widths of the radial seal surfaces 270 and 280 defined between the inner diameter (L2) and the outer diameter (L1) of the stepped portion provided in the section are the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11. Are provided to be larger than the width of the seal surfaces 270 and 280 in the region where the difference between them is small.

  Further, when the areas of the seal surface 270 and the seal surface 280 are compared, the inner diameter (L2) of the seal surface 280 is larger than the inner diameter (L2) of the seal surface 270, so that the first rotary piston 19U. The area of the sealing surface is larger than the area of the sealing surface of the second rotary piston 19D.

  As described above, according to the rotary compressor employing the two-stage compression, the differential pressure generated in the first stage (upper stage) compression element is larger than the differential pressure generated in the second stage (lower stage) compression element. It is known. Therefore, by providing the area of the sealing surface of the first rotating piston 19U larger than the area of the sealing surface of the second rotating piston 19D, the working fluid in the high-pressure state in the storage space 10 of the sealed container 1 can be efficiently transferred to the suction chamber. It is possible to suppress the flow into 11a, and it is possible to reduce the reduction in the capacity of the rotary compressor.

  The structure shown in FIGS. 4 to 7 described in the first embodiment can be adopted as the shape of the sealing surface of the first rotating piston 19U and the shape of the sealing surface of the second rotating piston 19D. In addition, it is possible to adopt the structure shown in FIGS. 9 and 10 described in the second embodiment.

(Embodiment 4)
In each of the above embodiments, the inner diameter and the outer diameter of the roller 20 of the rotary piston 19 facing the front head 13 and the rear head 14 in a region where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is large. As viewed from the blade 21, the width of the seal surface in the radial direction defined between them is larger than the width of the seal surface in the region where the difference between the internal pressure of the sealed container 1 and the internal pressure of the cylinder chamber 11 is small. A configuration is adopted in which the width of the radial seal surface is larger on the suction portion side than on the discharge portion side. This is effective when “internal pressure in the vicinity of the suction portion <internal pressure in the sealed container 1≈internal pressure in the vicinity of the discharge portion” is established. This is because the differential pressure in the vicinity of the discharge part is small and the working fluid flows into the suction chamber 11a little, but the differential pressure in the vicinity of the suction part is large and the working fluid flows into the suction chamber 11a.

  On the other hand, in the rotary compressor, there may be a case where “internal pressure in the vicinity of the suction portion <internal pressure in the sealed container 1 <internal pressure in the vicinity of the discharge portion” is established. In such a case, the width of the sealing surface in the radial direction when viewed from the blade 21, as shown in the sealing surfaces 290a and 290b shown in FIGS. 14 and 15, rather than the structure shown in the first to third embodiments. However, it is also possible to adopt a configuration in which the side closer to the blade 21 is larger than the opposite side across the insertion hole 20a of the roller 20. This is because, when “internal pressure near the suction portion <internal pressure of the sealed container 1 <internal pressure near the discharge portion” is established, the differential pressure is large at both the vicinity of the discharge portion and the vicinity of the suction portion. This is because it is considered that the flow into the suction chamber 11a increases, and it is more effective to increase the width of the seal surface at both the vicinity of the discharge portion and the vicinity of the suction portion.

  The shape of the seal surface shown in FIG. 14 is based on the same idea as the shape of the seal surface in FIG. 2 except that the shift direction is different. In addition, the shape of the seal surface in FIG. Although based on the same idea as the shape of the seal surface in FIG. 5, the structure shown in FIGS. 4, 6, and 7 described in Embodiment 1 is not limited to these shapes, but the displacement direction is different. It is also possible to employ the structure shown in FIGS. 9 and 10 described in the second embodiment.

The configuration in each of the above embodiments is particularly advantageous when a CO ₂ refrigerant is used as a working refrigerant that has attracted attention in recent years. This is because the CO ₂ refrigerant is likely to be in a higher pressure state than the conventional working fluid, and the above-described high-pressure working fluid is likely to flow into the cylinder chamber 11.

  In each of the above embodiments, the case where the present invention is applied to a rotary compressor is described. However, the structure based on the present invention includes not only a rotary compressor but also other similar compression element structures. It can be widely used for hermetic compressors.

  Therefore, the above-described embodiment disclosed herein is illustrative in all respects and is not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing which shows the compression element employ | adopted as the rotary compressor in Embodiment 1 based on this invention. It is a top view which shows the shape of the rotation piston employ | adopted for the rotary compressor in Embodiment 1 based on this invention. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. It is a top view which shows the shape of the other seal surface of the roller of the rotation piston employ | adopted for the rotary compressor in Embodiment 1 based on this invention. It is a top view which shows the shape of the other seal surface of the roller of the rotation piston employ | adopted for the rotary compressor in Embodiment 1 based on this invention. It is a top view which shows the shape of the other seal surface of the roller of the rotation piston employ | adopted for the rotary compressor in Embodiment 1 based on this invention. It is a top view which shows the shape of the other seal surface of the roller of the rotation piston employ | adopted for the rotary compressor in Embodiment 1 based on this invention. It is sectional drawing which shows the compression element employ | adopted as the rotary compressor in Embodiment 2 based on this invention. It is a top view which shows the shape of the rotation piston employ | adopted as the rotary compressor in Embodiment 2 based on this invention. FIG. 10 is a cross-sectional view taken along line XX in FIG. 9. It is a longitudinal cross-sectional view which shows the cross-section of the compression element of the rotary compressor in Embodiment 3 based on this invention. It is a top view which shows the shape of the rotation piston of the 1st step | paragraph employ | adopted as the rotary compressor in Embodiment 3 based on this invention. It is a top view which shows the shape of the 2nd rotation piston employ | adopted as the rotary compressor in Embodiment 3 based on this invention. It is a top view which shows the shape of the sealing surface of the roller of the rotary piston employ | adopted as the rotary compressor in Embodiment 4 based on this invention. It is another top view which shows the shape of the seal surface of the roller of the rotary piston employ | adopted as the rotary compressor in Embodiment 4 based on this invention. It is a longitudinal cross-sectional view which shows the whole structure of the rotary compressor in background art. FIG. 17 is a cross-sectional view taken along line XVII-XVII in FIG. 16. It is a 1st cross-sectional schematic diagram for demonstrating the pressure relationship of the working fluid in a compression element. It is a 2nd cross-sectional schematic diagram for demonstrating the pressure relationship of the working fluid in a compression element.

Explanation of symbols

  1 casing, 2 intermediate cylinder, 3 upper lid, 4 lower lid, 5 suction pipe, 6 discharge pipe, 7, 7A, 7B, 7C compression element, 8 drive element, 9 oil reservoir, 10 storage space, 11 cylinder chamber, 11A First cylinder chamber, 11B Second cylinder chamber, 11a Suction chamber, 11b Compression chamber, 12 Cylinder, 12b Discharge port, 12c Recess, 12d Blade sliding groove, 12e Bush hole, 13 Front head, 13a Bearing portion, 14 Rear head , 14a bearing part, 15 bolt, 16 muffler member, 17 discharge valve, 18 pin, 19 rotary piston, 19U first rotary piston, 19D second rotary piston, 20 roller, 20a insertion hole, 21 blade, 22 blade bush, 24 Stator, 25 Rotor, 26 Crankshaft, 26a Oil passage, 26b Eccentric shaft 27 Oil pump, 120 Suction pipe, 210 Seal surface, 220, 230, 240, 250, 260, 270, 280, 290a, 209b Seal surface, O Lubricating oil, P shaft center, P11, P12, P21, Center, Q Center of rotation, V1 imaginary line.

Claims (4)

An annular rotary piston that is inserted into the eccentric shaft portion (26b) of the crankshaft (26) and disposed in the cylinder chamber (11) inside the hermetic container (1) and revolves in the cylinder chamber (11). A hermetic type housing a compression element (7) that compresses the working fluid sucked into the suction side by (20) and discharges it to the discharge side, and a drive element (8) that rotates the rotating piston (20) eccentrically. A compressor,
The compression element (7) includes a cylinder (12), a front head (13) that sandwiches the cylinder (12) from one side, and a rear head (14) that sandwiches the cylinder (12) from the other side. Including the cylinder chamber (11a) in which the rotary piston (20) rotates eccentrically,
The rotor of the rotary piston (19) facing the front head (13) and the rear head (14) in a region where the difference between the internal pressure of the sealed container (1) and the internal pressure of the cylinder chamber (11) is large. The width of the radial seal surface defined between the inner diameter and the outer diameter of (20) is a region where the difference between the internal pressure of the sealed container (1) and the internal pressure of the cylinder chamber (11) is small. A hermetic compressor provided larger than the width of the sealing surface.   When the center (P21) of the insertion hole (20a) of the rotary piston (20) is viewed from the center (P11) of the outer diameter (L1), the internal pressure of the sealed container (1) and the cylinder chamber (11) The hermetic compressor according to claim 1, wherein the hermetic compressor is arranged so as to be shifted toward a region where the difference from the internal pressure is small. The hermetic compressor is disposed along the axial direction of the crankshaft (26) on the first cylinder chamber (11A) disposed on the front head (13) side and on the rear head (14) side. Has a second cylinder chamber (11B),
The area of the sealing surface of the rotor (20) of the first rotating piston (19U) accommodated in the first cylinder chamber (11A) is the second rotating piston (19D) accommodated in the second cylinder chamber (11B). The hermetic compressor according to claim 1, wherein the hermetic compressor is provided to be larger than an area of a sealing surface of the rotor (20).   The hermetic compressor according to any one of claims 1 to 3, wherein the working fluid used in the hermetic compressor is carbon dioxide.

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