KR20090012865A - Two stage rotary compressor - Google Patents

Abstract

A 2-stage rotary compressor is provided to prevent coupling deformation between a lower bearing and a lower cover and keep a sealed state between the lower bearing and the lower cover. A first bolt(B1) couples a lower bearing(161), a low pressure cylinder(121), a central plate(140), a high pressure cylinder(131) and an upper bearing(162) from the bottom in sequence. A lower cover(171) and the lower bearing, which form an intermediate pressure chamber, are coupled by a second bolt(B2) together with a gasket(G) for preventing the deformation of the lower cover and the lower bearing while keeping a sealed state therebetween.

Description

Rotary two stage compressor {TWO STAGE ROTARY COMPRESSOR}

1 is a view showing an example of a conventional rotary twin compressor.

Figure 2 is a schematic diagram showing an example of a cycle comprising a rotary two-stage compressor according to the present invention.

3 is a view showing an example of a rotary two-stage compressor according to the present invention.

4 is a view showing an example of a low pressure compression assembly of a rotary two-stage compressor according to the present invention.

5 and 6 are a part of the rotary two-stage compressor according to the present invention is shown from above and below.

7 is a view showing a part of the rotary two-stage compressor according to the present invention cut away.

8 is a view showing an example of a rotary shaft of a rotary two-stage compressor according to the present invention.

9 is a view showing an example of the internal flow path of the rotary two-stage compressor according to the present invention.

10 is a view showing an intermediate pressure chamber installation structure of a rotary two-stage compressor according to the present invention.

<Explanation of symbols on main parts of the drawings>

100: rotary compressor 110: electric motor

120: low pressure compression assembly 130: high pressure compression assembly

140: intermediate plate 151: inlet pipe

152: outflow pipe 153: injection pipe

180: inner euro

The present invention relates to a rotary compressor having an internal flow path inside the sealed container in order to communicate the compression spaces provided in the sealed container, and in particular, a rotary type that can prevent refrigerant leakage in the intermediate pressure chamber provided between the compressed spaces. A two stage compressor.

In general, a compressor is a mechanical device that increases pressure by receiving power from a power generator such as an electric motor or a turbine to compress air, refrigerant, or various other working gases. It is widely used throughout.

These compressors can be classified into reciprocating compressors for compressing refrigerant while linearly reciprocating inside the cylinders by forming a compression space in which the working gas is absorbed and discharged between the piston and the cylinder. Rotary compressor that compresses the refrigerant while the roller is eccentrically rotated along the inner wall of the cylinder to form a compression space in which the working gas is sucked and discharged between the roller and the cylinder which are eccentrically rotated. And a scroll compressor for compressing the refrigerant while the turning scroll is rotated along the fixed scroll to form a compressed space in which the working gas is sucked and discharged between the orbiting scroll and the fixed scroll. Divided into

Particularly, the rotary compressor includes two rollers and two cylinders at the upper and lower portions, and a rotary twin compressor at the upper and lower rollers and the cylinder pair compresses part of the total compression capacity and the other and the upper and lower portions. Rotary two-stage with two rollers and two cylinders, two cylinders in communication, one pair compresses relatively low pressure refrigerant, and the other pair compresses relatively high pressure refrigerant after low pressure compression More advanced, such as a compressor.

In the Republic of Korea Patent Publication No. 1994-001001 a rotary compressor is disclosed. The motor is located inside the shell, and a rotating shaft is installed to penetrate the motor. In addition, a cylinder is located under the electric motor, and an eccentric portion fitted to the rotating shaft and a roller fitted to the eccentric portion are located inside the cylinder. The cylinder has a coolant discharge hole and a coolant inlet hole, and a vane is provided between the coolant discharge hole and the coolant inlet hole to prevent the uncompressed low pressure refrigerant from mixing with the compressed high pressure refrigerant. In addition, a spring is installed at one end of the vane to maintain the eccentric and rotating roller and the vane in contact. When the rotating shaft is rotated by the motor, the eccentric portion and the roller rotate along the inner circumference of the cylinder to compress the refrigerant gas, and the compressed refrigerant gas is discharged through the refrigerant discharge hole.

Republic of Korea Patent Publication No. 10-2005-0062995 discloses a rotary twin compressor. Referring to FIG. 1, two cylinders 1035 and 1045 and an intermediate plate 1030 which compress the same capacity are provided, and the compression capacity is improved by twice compared to the first stage compressor.

Conventional twin rotary compressors are compressed after being compressed in two cylinders, and are discharged. Therefore, even though the two cylinders and the intermediate plate are fastened by one bolt, the pressure difference between the refrigerant compressed in each of the two cylinders and the discharged refrigerant are almost the same. Therefore, the refrigerant does not leak.

However, since the rotary two stage compressor used for high compression is discharged after continuous compression in two cylinders, the pressure of refrigerant compressed in one cylinder and the pressure of refrigerant discharged while continuously passing two cylinders are discharged. Since the difference is large, there is a problem that the refrigerant leaks.

The present invention has been made to solve the above-described problems of the prior art, in the compressor is compressed while flowing along the low pressure cylinder, the intermediate pressure chamber, the inner passage, the high pressure cylinder, the pressure of the primary compressed refrigerant and continuous compression It is an object of the present invention to provide a rotary two-stage compressor that can prevent leakage of refrigerant even when a large pressure difference of the refrigerant discharged through it is generated.

The present invention for solving the above problems is a sealed container; A rotating shaft which is provided in the sealed container and supplies oil while transmitting rotational force; A low pressure compression assembly in which primary compression of the refrigerant is performed inside the low pressure cylinder according to the rotation of the rotary shaft; A high pressure compression assembly in which secondary compression of the refrigerant compressed first in the high pressure cylinder is performed according to the rotation of the rotary shaft; A bearing and cover in communication with the low pressure compression assembly and the high pressure compression assembly and forming an intermediate pressure chamber in which the primary compressed refrigerant is mixed with the medium pressure refrigerant introduced from the outside before the secondary compression; An internal flow path through which the refrigerant flows through the low pressure cylinder, the high pressure cylinder, and an intermediate pressure communication hole respectively formed in the bearing; A first bolt for fastening the bearing to the low pressure cylinder and the high pressure cylinder; In addition, the second bolt for fastening the cover to the bearing; provides a rotary two-stage compressor comprising a.

In addition, provided between the bearing and the cover, the gasket is fastened to the bearing with the cover by the second bolt; provides a rotary two-stage compressor further comprising.

In addition, the intermediate plate for partitioning the high pressure cylinder and the low pressure cylinder up and down; further comprising, the bearing is fastened to the high pressure cylinder, the middle plate and the low pressure cylinder in the lower pressure cylinder, the cover is characterized in that the rotary is fastened in the lower bearing It provides a two-stage compressor.

In addition, there is provided a rotary two-stage compressor, characterized in that the length of the first bolt is longer than the length of the second bolt.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a schematic diagram showing an example of a cycle including a rotary two-stage compressor according to the present invention. The heating cycle includes components such as a rotary two stage compressor 100, a condenser 300, an evaporator 400, a phase separator 500, and a four-way valve 600. Among them, the condenser 300 constitutes an indoor unit, and the compressor 100, the evaporator 400, and the phase separator 500 constitute an outdoor unit. The refrigerant compressed by the compressor 100 is introduced into the condenser 300 of the indoor unit through the four-way valve 600, and the compressed refrigerant gas is condensed by exchanging heat with the surroundings. The condensed refrigerant passes through the expansion valve to low pressure. The refrigerant passing through the expansion valve is separated into gas and liquid in the phase separator 500, and the liquid flows into the evaporator 400. The liquid is evaporated by heat exchange in the evaporator 400 and flows into the accumulator 200 in a gas state, and flows into the low pressure compression assembly (not shown) through the refrigerant inlet pipe 151 of the compressor 100 in the accumulator 200. do. In addition, the gas separated from the phase separator 500 is introduced into the compressor 100 through the injection pipe 153. The medium pressure refrigerant compressed by the low pressure compression assembly of the compressor 100 and the refrigerant introduced through the injection tube 153 are introduced into the high pressure compression assembly (not shown) of the compressor 100 and compressed to high pressure. The discharge pipe 152 is discharged to the outside of the compressor 100 again.

3 is a view showing an example of a rotary two-stage compressor according to the present invention. Rotary two-stage compressor 100 according to an embodiment of the present invention, the lower pressure compression assembly 120, the intermediate plate 140, the high pressure compression assembly 130 and the electric motor 110 from the bottom in the sealed container 101 It includes. In addition, it includes a refrigerant inlet pipe 151 penetrating through the sealed container 101 and connected to the accumulator 200 and a refrigerant discharge pipe 152 for discharging the compressed refrigerant to the outside of the sealed container.

The motor 110 includes a stator 111, a rotor 112, and a rotation shaft 113. The stator 111 includes laminations in which ring-shaped electrical steel sheets are laminated, and coils wound on the laminations. The rotor 112 also has a lamination in which an electronic steel sheet is laminated. The rotating shaft 113 penetrates the center of the rotor 112 and is fixed to the rotor 112. When a current is applied to the motor 110, the rotor 112 rotates by the mutual electromagnetic force between the stator 111 and the rotor 112, and the rotating shaft 113 fixed to the rotor 112 also rotates with the rotor 112. Rotate together. The rotating shaft 113 extends from the rotor 112 to the low pressure compression assembly 120 so as to penetrate the center portion of the low pressure compression assembly 120, the intermediate plate 140, and the high pressure compression assembly 130.

The low pressure compression assembly 120 and the high pressure compression assembly 130 are stacked in the order of the low pressure compression assembly 120-the middle plate 140-the high pressure compression assembly 130 from the bottom with the intermediate plate 140 interposed therebetween. Can be. Conversely, the high pressure compression assembly 120, the middle plate 140, and the high pressure compression assembly 130 may be stacked in the order from the bottom. In addition, regardless of the stacking order of the low pressure compression assembly 120, the middle plate 140 and the high pressure compression assembly 130, the lower bearing and the upper bearing 161 and the upper bearing 162 are respectively installed It helps the rotation of the rotary shaft 113, and supports the load of each component of the two-stage compression assembly stacked vertically. The upper bearing 162 is three-point welded to the hermetic container 101 to support the load of the two-stage compression assembly and fix it to the hermetic container 101.

The low pressure compression assembly 120 is connected to the refrigerant inlet pipe 151 introduced through the sealed container 101 from the outside. In addition, a lower bearing 161 and a lower cover 171 are positioned below the low pressure compression assembly 120, and an intermediate pressure chamber Pm is formed between the lower bearing 161 and the lower cover 171. The intermediate pressure chamber Pm is a space in which the refrigerant compressed in the low pressure compression assembly 120 is discharged, and is a space in which the refrigerant is temporarily stored before the refrigerant is introduced into the high pressure compression assembly 130, from the low pressure compression assembly 120. The high pressure compression assembly 130 serves as a buffer space on the flow path through which the refrigerant flows.

Looking at the structure in which the intermediate pressure chamber (Pm) is formed in the lower bearing 161, for example, the lower bearing 161 is protruded downward, the center portion in which the rotary shaft 131 is inserted / installed and the peripheral portion of the lower cover 171 abuts The lower cover 171 has a hole through which the rotating shaft 131 passes, and is formed in a flat shape in close contact with the lower bearing 161. In this case, the downwardly protruding peripheral portion of the lower bearing 161 and the flat peripheral portion of the lower cover 171 are bolted to the low pressure cylinder 121 at once. As another example, the lower bearing 161 may protrude downward only at the center of which the rotation shaft 113 is inserted / installed, and at the same time, other portions thereof may be formed flat, and the lower cover 171 may have a hole through which the rotation shaft 113 penetrates. The provided central portion may be formed flat, and at the same time, the periphery thereof may be stepped up to protrude upward. At this time, the flat peripheral portion of the lower bearing 161 and the peripheral portion protruding upwardly of the lower cover 171 are installed to be bolted to the low pressure cylinder 121 at once. In this case, the shape of the lower bearing 161 can be simplified to reduce the number of work, and the shape of the lower cover 171 can also be easily manufactured by pressing. Furthermore, the shape and the fastening method of the lower bearing 161 and the lower cover 171 are not limited to the above-mentioned method, and will be described an example in which the intermediate pressure chamber Pm is formed in the lower bearing 161. However, the intermediate pressure chamber Pm may be formed in any one of the upper bearing 162 and the intermediate plate 140.

A discharge port (not shown) is installed on an upper portion of the upper bearing 162 positioned above the high pressure compression assembly 130. The high pressure refrigerant discharged from the high pressure compression assembly 130 through the discharge port of the upper bearing 162 is discharged to the outside through the refrigerant discharge pipe 152 located on the top of the sealed container 101.

The lower bearing 161, the low pressure compression assembly 120, the intermediate plate 140, and the high pressure compression assembly 130 have an internal flow path 180 connecting refrigerant from the low pressure compression assembly 120 to the high pressure compression assembly 130. ) Is formed. The inner flow passage 180 is formed vertically so as to be substantially parallel to the axial direction of the compressor.

Since the inner passage 180 is not a separate tube, the injection tube 153 (shown in FIG. 2) into which the refrigerant gas separated from the above-described phase separator 500 (shown in FIG. 2) flows into the inner passage 180. It can be installed anywhere. For example, a through hole (not shown) is formed in any one of the lower bearing 161, the intermediate plate 140, and the high pressure cylinder 131 forming the intermediate pressure chamber Pm, and the injection tube 153 is formed in the through hole. ), The refrigerant gas can be introduced, and the compression efficiency can be increased.

4 is a view showing an example of a low pressure compression assembly of a rotary two-stage compressor according to the present invention. The low pressure compression assembly 120 includes a low pressure cylinder 121, a low pressure eccentric 122, a low pressure roller 123, a low pressure vane 124, a low pressure elastic member 125, a low pressure inlet hole 126, and an intermediate pressure discharge hole. 127. The rotating shaft 113 passes through the center of the low pressure cylinder 121, and the low pressure eccentric portion 122 is fixed to the rotating shaft 113. In this case, the low pressure eccentric portion 122 may be integrally formed with the rotation shaft 113. In addition, the low pressure roller 123 is rotatably installed in the low pressure eccentric part 122, and the low pressure roller 123 rotates while rolling along the inner diameter of the low pressure cylinder 121 as the rotary shaft 113 rotates. The low pressure inlet hole 126 and the intermediate pressure discharge hole 127 are formed at both sides of the low pressure vane 124. In addition, the space in the low pressure cylinder 121 is partitioned by the low pressure vane 124 and the low pressure roller 123, and the refrigerant before and after compression coexists in the low pressure cylinder 121. As shown in FIG. It is partitioned by the low pressure vane 124 and the low pressure roller 123, and the portion including the low pressure refrigerant inlet hole 126 is the low pressure refrigerant inlet (S _l ), the middle portion containing the intermediate pressure discharge hole 127 in the middle It is called a pressurized refrigerant discharge part D _m . Here, the low pressure elastic member 125 is a means for applying a force to the low pressure vane 124 so that the low pressure vane 124 maintains contact with the low pressure roller 123. The vane hole 124h formed in the low pressure cylinder 121 is formed to penetrate the low pressure cylinder 121 laterally so that the low pressure vane 124 can be located. Through the vane hole 124, the low pressure vane 124 is guided, and the low pressure elastic member 125 that applies the force to the low pressure vane 124 extends through the low pressure cylinder 121 to the sealed container 101. . One end of the low pressure elastic member 125 is in contact with the low pressure vane 124, the other end is in contact with the closed container 101, so that the low pressure vane 124 maintains contact with the low pressure roller 123. To push.

In addition, the low pressure cylinder 121 has an intermediate pressure communication hole so that the refrigerant compressed in the low pressure compression assembly 120 may flow into the high pressure compression assembly 130 through the intermediate pressure chamber Pm formed by the lower bearing 161. 120a) is formed. The intermediate pressure communication hole 120a does not overlap with the refrigerant inlet pipe 151 inserted into the low pressure inlet hole 126, that is, the internal flow path 180 and the refrigerant inlet pipe 151 do not overlap with each other. ) Is formed. Although partially overlapped with the refrigerant inflow pipe 151, the medium pressure refrigerant is formed to flow into the high pressure compression assembly 130 from the intermediate pressure chamber Pm. However, in this case, since the internal flow path 180 can see the loss by the cross-sectional area overlapping the refrigerant inlet pipe 151, it is not preferable. In addition, as the refrigerant bypasses the vicinity of the refrigerant inlet pipe 151, the pressure may decrease.

As shown in FIG. 4, when the low pressure eccentric portion 122 rotates by the rotation of the rotary shaft 113, and the low pressure roller 123 rolls along the low pressure cylinder 121, the volume of the low pressure inflow portion S ₁ is decreased. As the low pressure inlet (S ₁ ) becomes low as it is increased, the refrigerant flows through the low pressure inlet (126). On the other hand, the intermediate pressure discharge portion (D _m), the volume is filled with the refrigerant in the intermediate pressure discharge portion (D _m) compression, it loses of, and is discharged through the intermediate pressure discharge holes (127). As the low pressure eccentric part 122 and the low pressure roller 123 rotate, the volume of the low pressure inlet part S ₁ and the intermediate pressure discharge part D _m continuously changes, and discharges the compressed refrigerant every one revolution.

5 to 7 is a view showing a part of a rotary two-stage compressor according to an embodiment of the present invention. In order from the bottom, the lower bearing 161, the low pressure compression assembly 120, the intermediate plate 140, and the high pressure compression assembly 130 are stacked. As described above, the low pressure refrigerant is introduced into the low pressure cylinder 121 through the refrigerant inlet pipe 151 and the low pressure inlet hole 126 and compressed, and then the low pressure compression assembly 120 through the intermediate pressure discharge hole 127. ) Is discharged into the intermediate pressure chamber (Pm), which is a space limited by the lower surface of the bottom and the lower bearing 161 and the lower cover 171. The intermediate pressure discharge hole 161h is formed in the lower bearing 161 so that the intermediate pressure discharge hole 127 and the intermediate pressure discharge hole 161h of the lower bearing 161 overlap each other, and the lower bearing 161 is formed. A valve (not shown) is installed at the lower portion of the intermediate pressure discharge hole 161h of the low pressure compression assembly 120, and when the refrigerant compressed in the intermediate pressure discharge portion Dm of the low pressure compression assembly 120 is compressed to a predetermined pressure, the intermediate pressure chamber Pm is To be discharged. The refrigerant discharged into the intermediate pressure chamber Pm is formed in the intermediate pressure communication hole 120a and the intermediate plate 140 formed in the low pressure cylinder 121 through the intermediate pressure communication hole 161a formed in the lower bearing 161. It passes through the intermediate pressure communication hole 140a and flows into the high pressure compression assembly 130 through the intermediate pressure inlet groove 130a of the high pressure cylinder 131. Intermediate pressure communication hole 161a of the lower bearing 161, intermediate pressure communication hole 120a of the low pressure compression assembly, intermediate pressure communication hole 140a of the intermediate plate 140, and intermediate pressure inflow of the high pressure compression assembly 130 The groove 130a forms an internal flow path 180 through which the medium pressure refrigerant compressed by the low pressure compression assembly 120 passes. At this time, the intermediate pressure inlet groove 130a of the high pressure compression assembly 130 is formed in the form of an inclined groove so as to communicate with the internal space of the high pressure cylinder 131. A lower portion of the intermediate pressure inlet groove 130a is formed to contact the intermediate pressure communication hole 140a of the intermediate plate 140 to form a part of the internal flow path 180, and the compressed medium pressure refrigerant is medium pressure inlet. It is introduced into the high pressure cylinder 131 through the groove 130a. When the medium pressure refrigerant flows into the high pressure compression assembly 130 through the internal flow path 180, the high pressure compression assembly 130 compresses the medium pressure refrigerant to the high pressure in the same operating principle as the low pressure compression assembly 120. do.

As described above, when the internal flow path 180 through which the medium pressure refrigerant passes is not formed by a separate pipe, but formed inside the sealed container 101, noise can be reduced, and the length of the internal flow path 180 is increased. It is possible to shorten the loss of the refrigerant pressure due to the resistance can be reduced. In addition, in the above, an example in which the intermediate pressure chamber Pm is formed in the lower bearing 161 has been described, but the intermediate pressure chamber Pm may be formed in any one of the upper bearing 162 and the intermediate plate 140. . Accordingly, although the specific structure may vary slightly, in any case, the internal flow path 180 is formed inside the two-stage compression assembly, so that the medium pressure refrigerant compressed in the low pressure compression assembly 120 through the internal flow path 180 is formed. Guided to the high pressure compression assembly 130. Through this configuration, it is possible to shorten the length of the flow path through which the medium pressure refrigerant is guided, to minimize the flow loss, and to reduce noise and vibration without passing through the connection pipe passing through the hermetic container 101.

At this time, the intermediate pressure communication hole 120a of the low pressure compression assembly 120 constituting the internal flow path 180 to prevent the internal flow path 180 from being blocked by the refrigerant inlet pipe 151, and the intermediate pressure of the intermediate plate 140. The communication hole 140a and the intermediate pressure inlet groove 130a of the high pressure compression assembly 130 are formed to be spaced apart from the refrigerant inlet pipe 151 when viewed in the axial direction of the compressor 100.

The intermediate pressure communication hole 161a of the lower bearing 161 is formed to avoid the position where the refrigerant inlet pipe 151 is inserted so as not to overlap with the refrigerant inlet pipe 151 connected to the low pressure cylinder 121. The refrigerant inlet pipe 151 is inserted into the low pressure inlet hole 126 formed in the low pressure cylinder 121. The low pressure inlet hole 126 is formed close to the low pressure vane insertion hole 124h into which the low pressure vane 124 (shown in FIG. 4) is inserted. This is because as the low pressure inlet hole 126 is farther from the low pressure vane 124 (shown in FIG. 4), a dead volume that does not contribute to the compression of the refrigerant in the inner space of the low pressure cylinder 121 increases.

In addition, the intermediate pressure inlet groove 130a of the high pressure cylinder 131 is not formed to penetrate from the bottom to the top of the high pressure cylinder 131, and communicates with the internal space of the high pressure cylinder 131 from the bottom of the high pressure cylinder 131. It is formed obliquely. At this time, the intermediate pressure inlet groove 130a is formed close to the high pressure vane hole 134h into which the high pressure vane (not shown) is inserted. As in the low pressure compression assembly, since the intermediate pressure inlet groove 130a is formed close to the high pressure vane (not shown), it is possible to reduce the dead volume in the space inside the high pressure cylinder 131.

The low pressure vanes 124 and the high pressure vanes (not shown) are located on the same axis. Therefore, the intermediate pressure communication hole 161a formed in the lower bearing 161 and the intermediate pressure inflow groove 130a formed in the high pressure cylinder 131 are not formed on the same axis, and horizontal positions are formed to be spaced apart from each other. In the third embodiment of the present invention, in order to connect the intermediate pressure communication hole 161a of the lower bearing 161 and the intermediate pressure communication hole 130a of the high pressure cylinder 131, the intermediate pressure communication hole of the low pressure cylinder 121 is connected. The intermediate pressure communication hole 140a of the 120a and the intermediate plate 140 is formed in a substantially spiral shape. The intermediate pressure communication hole 120a of the low pressure cylinder 121 and the intermediate pressure communication hole 140a of the intermediate plate 140 are formed to overlap each other in a spiral. That is, the intermediate pressure communication hole 120a of the low pressure cylinder 121 and the intermediate pressure communication hole 140a of the intermediate plate 140 overlap to form a spiral communication hole. At this time, one end of the spiral communication hole overlaps the intermediate pressure communication hole 161a of the lower bearing 161, and the other end overlaps the intermediate pressure inlet groove 130a of the high pressure cylinder 131. Here, one end of the intermediate pressure communication hole 120a of the low pressure cylinder 121 penetrates to be connected to the intermediate pressure communication hole 161a of the lower bearing 161. That is, the intermediate pressure communication hole 120a of the low pressure cylinder 121 is formed such that one end contacting the intermediate pressure communication hole 161a of the lower bearing 161 penetrates in the vertical direction of the low pressure cylinder 121. The remaining portion of the communication hole 120a is formed in a spiral shape as the lower portion of the intermediate pressure communication hole 120a gradually increases from one end to the other end. In addition, the intermediate pressure communication hole 140a of the intermediate plate 140, on the other hand, the other end of the spiral communication hole, that is, the other end overlapping the intermediate pressure inlet groove 130a of the high pressure cylinder 130 is perpendicular to the intermediate plate 140. It is formed to penetrate in the direction. In addition, as the upper end portion of the intermediate pressure communication hole 120a gradually increases from one end overlapping with the intermediate pressure communication hole 161a of the lower bearing 161 to the other end, it is formed in a spiral shape as a whole.

When the intermediate pressure communication hole 120a of the low pressure cylinder 121 and the intermediate pressure communication hole 140a of the intermediate plate 140 are formed in a spiral shape, the refrigerant is formed in the intermediate pressure communication hole 120a and the middle of the low pressure cylinder 121. The resistance received along the intermediate pressure communication hole 140a of the plate 140 is reduced. Of course, the intermediate pressure communication hole (120a) of the low pressure cylinder 121 and the intermediate pressure communication hole (140a) of the intermediate plate 140 is not only a spiral, but also a circular arc-like shape that does not change the height of the top or bottom. It may be formed as.

Further, when the intermediate pressure communication hole 120a of the low pressure cylinder 121 and the intermediate pressure communication hole 140a of the intermediate plate 140 are formed in a spiral or arc shape, the intermediate pressure communication holes 120a and 140a of the spiral or arc shape are formed. Fastening holes 120b and 140b may be formed in the central portion of the. The lower bearing 161, the low pressure cylinder 121, the intermediate plate 140, the high pressure cylinder 131, and the upper bearing 162 are generally fastened through bolts. At this time, the fastening holes 161b, 120b, 130b, 140b, and 162b to which the bolts are fastened are the refrigerant inlet pipe 151, the medium pressure communication hole 161a, 120a, 130a, and 162a, the medium pressure inlet groove 140a, and the middle. Various members such as the pressure discharge hole 127 and the inner flow path 180 should be avoided. In addition, the fastening holes 161b, 120b, 130b, 140b, and 162b should be formed in at least three places, and should be able to evenly distribute the fastening force to the entire compressor assembly 105. In this case, the intermediate pressure communication hole 120a of the low pressure cylinder 121 and the intermediate pressure communication hole 140a of the intermediate plate 140 are formed of the intermediate pressure communication hole 161a of the lower bearing 161 and the high pressure cylinder 131. Since the length is longer than that of the intermediate pressure inlet groove 130a, it prevents the formation of a plurality of fastening holes 161b, 120b, 130b, 140b and 162b. Therefore, when the intermediate pressure communication hole 120a of the low pressure cylinder and the intermediate pressure communication hole 140a of the intermediate plate 140 are formed in a spiral or arc shape, the fastening hole 161b, 120b, 130b, 140b, 162b can be formed, which is advantageous for distributing a plurality of fastening holes 161b, 120b, 130b, 140b, 162b in the entire compressor assembly 105.

8 is a view showing an example of a rotary shaft provided in a rotary two-stage compressor according to the present invention. The low pressure eccentric portion 122 and the high pressure eccentric portion 132 are coupled to the rotary shaft 113. The low pressure eccentric 122 and the high pressure eccentric 132 are coupled to the rotating shaft 113 with a phase difference of generally 180 kHz to reduce vibration. In addition, the rotating shaft 113 is a hollow shaft having an empty inside, and has an oil communication hole 113a at the lower portion of the low pressure eccentric portion 122 and the upper portion of the high pressure eccentric portion 132. In addition, the rotating shaft 113 is formed of a hollow shaft, the inner portion (113h) is inserted into the stirrer (113b) of the thin plate bent in a spiral. The stirrer 113b is fitted to the inside 113h of the rotating shaft 113, and rotates together with the rotating shaft 113 when the rotating shaft 113 rotates. As the stirrer 113b rotates together by the rotation of the rotary shaft 113, oil filled in the lower portion of the sealed container 101 (shown in FIG. 3) rises along the inside of the rotary shaft 113 along the stirrer 113b. A portion of the low pressure roller 121, the intermediate plate 140 and the high pressure cylinder 131 through the oil communication hole 113a formed in the rotating shaft 113, and the low pressure roller 123 (shown in FIG. 4). And a high pressure roller (not shown).

9 is a view showing an example of the internal flow path of the rotary two-stage compressor according to the present invention. In the rotary two-stage compressor according to the present invention, the high pressure cylinder 131, the middle plate 140, the low pressure cylinder 121, and the lower bearing 161 are sequentially disposed below the upper bearing 162 fixed inside the sealed container 101. ) Is installed to overlap, the gasket (G) and the lower cover 171 is coupled to the lower side of the lower bearing 161 to form an intermediate pressure chamber (Pm), the intermediate pressure chamber (Pm) is a lower bearing 161, low pressure cylinder (121), the intermediate pressure communication hole (161a, 120a, 140a: shown in Figure 7) provided in the intermediate plate 140 and the intermediate pressure inlet hole (130a: shown in Figure 7) provided in the high pressure cylinder 131 It is installed to communicate with the inner flow path 180 made.

At this time, the refrigerant inlet pipe 151 is installed to penetrate the sealed container 101 to be inserted from one side of the low pressure cylinder 121 to be in communication with the compression space of the low pressure cylinder 121, the injection pipe 153 is similarly sealed The low pressure cylinder 121 penetrates the container 101 and is installed to be inserted into one side of the low pressure cylinder 121 so as to communicate with the intermediate pressure communication hole 120a (shown in FIG. 7) of the low pressure cylinder 121. Although the medium pressure communication hole 120a (shown in FIG. 7) of the cylinder 121 penetrates through the refrigerant inlet pipe 151, the medium pressure communication hole 120a (shown in FIG. 7) of the low pressure cylinder 121. It is installed to prevent the flow into.

Therefore, the refrigerant introduced into the low pressure cylinder 121 through the refrigerant inlet pipe 151 is first compressed in the low pressure compression assembly 120, flows along the intermediate pressure chamber Pm and the inner flow path 180, and simultaneously the injection pipe. It is combined with the refrigerant of the intermediate pressure state introduced through the 153, and then flows into the high pressure compression assembly 130, the second compression is discharged.

10 is a view showing an intermediate pressure chamber installation structure of a rotary two-stage compressor according to the present invention. The intermediate pressure chamber Pm of the rotary two-stage compressor according to the present invention includes a lower bearing 161 and a lower cover 171 positioned below the low pressure compression assembly 120, and a gasket installed therebetween to prevent leakage of refrigerant. (G), but the high-pressure cylinder 131, the middle plate 140, the low-pressure cylinder 121, the lower bearing 161 at the bottom of the upper bearing 162 welded and fixed inside the hermetic container 101 It is fastened by one bolt (B1), the gasket (G) and the lower cover 171 is fastened by the second bolt (B2) at the bottom of the lower bearing (161).

At this time, the first fastening holes (not shown) and the first fastening groove (1) to which the first bolt B1 is fastened to the low pressure cylinder 121, the intermediate plate 140, the high pressure cylinder 131, and the upper bearing 162. Second fastening holes (not shown) are formed close to the center of the rotating shaft 113, the second bolt (B2) is fastened to the lower cover 171, the gasket (G) and the low pressure cylinder (161). And a second fastening groove (not shown) is formed to be located farther from the center of the rotation shaft 113 than the first fastening holes and the first fastening groove, wherein the first and second fastening holes and the first and second fastening groove are circumferential. It is formed at regular intervals in the direction to evenly apply the clamping force throughout the compressor. In particular, the lower bearing 161 is preferably formed such that the inner diameter portion, that is, the rotation shaft 113 and the inserted portion protrude downward, while the outer diameter portion, that is, the portion to which the second bolt B2 is fastened, also protrudes downward. Do. That is, when the lower cover 171 is fastened to the outer diameter portion of the lower bearing 161 by the second bolt (B2), as the outer diameter portion of the lower bearing 161 is formed thicker than a predetermined thickness lower bearing 161 The length of the second fastening groove of the can also be long, because the second bolt (B2) more than a predetermined length can be fastened to the outer diameter portion of the lower bearing 161 to provide a predetermined fastening force by the second bolt (B2). To seal between the lower bearing 161 and the lower cover 171.

Of course, the first and second fastening holes and the first and second fastening grooves are formed at positions that do not interfere with various holes / grooves formed in each component, in particular, the intermediate pressure communication hole 161a forming the inner flow path 180. (120a, 140a: shown in Figure 7) and the intermediate pressure inlet hole (130a: shown in Figure 7) is preferably formed in a position not interfered with.

At this time, the first bolt (B1) is fastened from the lower bearing 161 to the upper bearing 162, while the second bolt (B2) is fastened only from the lower cover 171 to the lower bearing 161, the first bolt The length of (B1) is formed longer than the length of the second bolt (B2), the fastening force of the first bolt (B1) acts greater than the fastening force of the second bolt (B2). Therefore, when the first bearing B1 is fastened from the lower bearing 161 to the upper bearing 162, even if the fastening force of the relatively long first bolt B1 is large, the thickness of the component parts is relatively thick. When the deformation of the component does not occur, and when the lower cover 171 is fastened to the lower bearing 161 by the second bolt B2, the fastening force of the relatively short first bolt B1 acts small, and thus the lower cover 171. Even if the thickness of the) is relatively thin, the deformation of the lower cover 171 can be prevented. That is, the gap between the lower bearing 161 and the lower cover 171 may be eliminated, which may be caused by the fastening deformation, and further, the precision may not be precisely processed between the lower bearing 161 and the lower cover 171 and may have a predetermined elasticity. Since only the gasket G is inserted, the pressure between the lower bearing 161 and the lower cover 171 can be sealed so that the pressure in the intermediate pressure chamber Pm formed between the lower bearing 161 and the lower cover 171 is closed. 101) Even if the pressure is lower than the internal pressure, leakage of the refrigerant can be prevented.

The present invention is not limited to the above-mentioned method, but the above-described ones in which the intermediate pressure chamber Pm is formed in the lower bearing 161 are described, but the intermediate pressure chamber Pm may be similarly applied to the case in which the intermediate pressure chamber Pm is formed in the upper bearing 162. Can be.

In the above, the present invention has been described in detail by way of examples based on the embodiments of the present invention and the accompanying drawings. However, the scope of the present invention is not limited by the above embodiments and drawings, and the scope of the present invention will be limited only by the contents described in the claims below.

The rotary two-stage compressor according to the present invention configured as described above is a compressor in which a refrigerant is compressed while flowing along a low pressure cylinder, an intermediate pressure chamber, an internal flow path, and a high pressure cylinder, and the lower bearing has a low pressure cylinder, an intermediate plate, and a high pressure cylinder. The first compressed refrigerant and the injection pipe inside the intermediate pressure chamber are fastened to the upper bearing, and then the lower cover is fastened together with the gasket to the lower bearing to form the intermediate pressure chamber in the lower bearing. Although the pressure is lower than that of the secondary compressed refrigerant even if the external high pressure refrigerant is mixed through, it is possible to prevent the fastening deformation between the lower bearing and the lower cover, and furthermore, a gasket is installed between the lower bearing and the lower cover to maintain airtightness. There is an advantage that can prevent the leakage of the refrigerant, and further improve the compression performance.

Claims (4)

chest; A rotating shaft which is provided in the sealed container and supplies oil while transmitting rotational force; A low pressure compression assembly in which primary compression of the refrigerant is performed inside the low pressure cylinder according to the rotation of the rotary shaft; A high pressure compression assembly in which secondary compression of the refrigerant compressed first in the high pressure cylinder is performed according to the rotation of the rotary shaft; A bearing and cover in communication with the low pressure compression assembly and the high pressure compression assembly and forming an intermediate pressure chamber in which the primary compressed refrigerant is mixed with the medium pressure refrigerant introduced from the outside before the secondary compression; An internal flow path through which the refrigerant flows through the low pressure cylinder, the high pressure cylinder, and an intermediate pressure communication hole respectively formed in the bearing; A first bolt for fastening the bearing to the low pressure cylinder and the high pressure cylinder; And, And a second bolt that fastens the cover to the bearing. The method of claim 1, And a gasket installed between the bearing and the cover and fastened to the bearing together with the cover by a second bolt. The method of claim 1, It further comprises an intermediate plate for partitioning the high pressure cylinder and the low pressure cylinder up and down, The bearing is fastened to the high pressure cylinder, the middle plate and the low pressure cylinder under the low pressure cylinder, The cover is a rotary two-stage compressor, characterized in that fastened at the bottom of the bearing. The method of claim 1, Rotary type two-stage compressor, characterized in that the length of the first bolt is longer than the length of the second bolt.

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