JP5793649B2 - Hermetic compressor - Google Patents

Description

  The present invention relates to a suction compressor for a hermetic compressor used in a home electric refrigerator-freezer, a showcase, and the like.

  In recent years, the demand for protecting the global environment has been increasing, and there is a strong demand for particularly high efficiency in refrigerators and other refrigeration cycle apparatuses.

  Conventionally, as this type of hermetic compressor, there is an example using a resin suction muffler (see, for example, Patent Document 1).

  FIG. 3 is a longitudinal sectional view of a conventional hermetic compressor described in Patent Document 1, and FIG. 4 is a main part sectional view of a suction muffler of the conventional hermetic compressor described in the same patent document.

  As shown in FIGS. 3 and 4, the conventional hermetic compressor 1 stores oil 5 at the bottom of the hermetic container 3 having the suction pipe 2 and is filled with a refrigerant gas 7. The compressor body 9 is elastically supported with respect to the sealed container 3 by suspension springs 11.

  The compressor body 9 includes an electric element 13 and a compression element 15 disposed above the electric element 13, and the electric element 13 includes a stator 17 and a rotor 19.

  The compression element 15 includes a crankshaft 25 having an eccentric shaft 21 and a main shaft 23, a block 31 in which a cylinder 29 forming a compression chamber 27 is integrally formed, a piston 33, and a valve that seals an end surface of the cylinder 29. A plate 35, a suction valve (not shown) for opening and closing a suction hole 37 provided in the valve plate 35, and a connecting means 39 for connecting the eccentric shaft 21 and the piston 33 are provided.

  The main shaft 23 of the crankshaft 25 is rotatably supported by the bearing portion 41 of the block 31 and the rotor 19 is fixed. The crankshaft 25 includes an oil supply mechanism (not shown).

  Further, the suction muffler 45 is sandwiched and fixed by a valve plate 35 attached to the end face of the cylinder 29 and a cylinder head 43 surrounding the valve plate 35.

  The suction muffler 45 is formed of a resin such as PBT, and includes a muffler main body 49 that forms a sound deadening space 47, a cover 55 having a tail pipe 51 and a communication pipe 53.

  The tail pipe 51 includes a tail pipe outlet 57 that opens into the muffler body 49 and a tail pipe inlet 59 that is located outside the cover 55.

  The communication pipe 53 includes a communication pipe inlet 61 that opens into the muffler main body 49 and a communication pipe outlet 63 that extends to the outside of the cover 55 and is connected to the suction hole 37.

  The operation of the hermetic compressor 1 configured as described above will be described below.

  First, in the hermetic compressor, an electric current is passed through the stator 17 to generate a magnetic field, and the rotor 19 fixed to the main shaft 23 is rotated, whereby the crankshaft 25 is rotated and attached to the eccentric shaft 21 so as to be freely rotatable. The piston 33 reciprocates in the cylinder 29 through the connected connecting means 39.

  Then, the reciprocating motion of the piston 33 repeats the suction and compression of the refrigerant gas 7 into the compression chamber 27 and the discharge to the refrigeration cycle (not shown).

  Next, the flow of the refrigerant gas 7 will be described.

  The refrigerant gas 7 sucked from the suction pipe 2 through the tail pipe inlet 59 has a relatively high temperature refrigerant present inside the sealed container 3 because the tail pipe 51 and the communication pipe 53 are isolated from the side wall of the muffler body 49. The gas 7 flows into the cylinder 29 while being thermally insulated from the gas 7.

  However, since the tail pipe inlet portion 59 faces the opening end of the suction pipe 2, the refrigerant gas 7 tends to flow into the tail pipe inlet portion 59. However, since the tail pipe inlet 59 does not include means for minimizing the mixing of the high-temperature refrigerant gas 7 that flows inside the sealed container 3, the temperature of the refrigerant gas 7 compressed in the cylinder 29 is high. The efficiency is reduced.

  As a means for coping with this, it is conceivable to form a refrigerant retaining portion (not shown) including a recessed portion in a range including the tail tube inlet portion 59.

  With this configuration, it is possible to minimize the mixing of high-temperature refrigerant gas that flows inside the closed container into the suction muffler, and to increase the efficiency of the compressor.

  However, if the diameter of the tail pipe 51 is made larger in order to take in more refrigerant gas into the suction muffler, the amount of noise generated during the suction of the refrigerant gas increases, and the radiated sound is generated at the refrigerant retention part. Amplification may increase the noise of the hermetic compressor.

  On the other hand, as a means for reducing the noise of the hermetic compressor caused by the radiated sound from the suction muffler 45, the suction passage formed in the cylinder head 43 and the suction muffler 45 is provided with two open ends, and the suction There is an example in which the difference in length from the hole 37 to each opening end, or the installation distance between each opening end is set to about ½ of the average circumference of the space in the sealed container (see, for example, Patent Document 2).

  FIG. 5 is a schematic cross-sectional view of a conventional hermetic compressor described in Patent Document 2.

  As shown in FIG. 5, the conventional hermetic compressor 71 includes a valve plate 75 having a suction hole 73, a cylinder head 77, and a suction muffler 79.

  A suction passage 81 formed in the cylinder head 77 and the suction muffler 79 is provided with a first opening end 83 and a second opening end 85, and a passage length L1 from the suction hole 73 to the first opening end 83; The difference from the passage length L2 from the suction hole 73 to the second opening end 85 is about ½ of the average circumferential length L of the space in the sealed container 87.

  In the hermetic compressor 71 configured as described above, if the difference between the lengths of the passage lengths L1 and L2 is about ½ of the average circumferential length L, the passage length L2 becomes very long. A configuration in which suction loss occurs or the passage length L1 becomes very short, and noise generated when refrigerant gas is sucked is directly radiated into the sealed container 87.

  Therefore, noise with a specific frequency can be silenced by anti-phase sound wave radiated from each opening end as intended, but noise other than the specific frequency cannot be silenced by interference, resulting in increased noise. There was a case.

  Similarly, a tail pipe (not shown) communicating with the suction muffler 79 connected to the suction chamber (not shown) is used as a means for reducing the noise of the hermetic compressor caused by the radiated sound from the suction muffler 79. And two auxiliary tail pipes that directly communicate the space inside the sealed container and the suction chamber. The opening ends of the tail pipe and the auxiliary tail pipe (not shown) are reduced in diameter, and the auxiliary tail pipes are respectively There is an example in which the axis is bent so as to form an angle of approximately 155 degrees at the intermediate portion of the auxiliary tail pipe, and the opening ends of the auxiliary tail tubes are arranged so as to be separated from each other (see, for example, Patent Document 3).

  However, in the configuration of the conventional hermetic compressor described in Patent Document 3, since the opening end of the tail tube is reduced in diameter, the sound emitted from the tail tube is reduced, and the opening end of the tail tube is reduced in diameter. The auxiliary tail pipe can compensate for a decrease in the amount of refrigerant gas sucked as a result.

  However, since the auxiliary tail pipe communicates directly with the suction chamber without passing through the suction muffler, the noise of the hermetic compressor increases due to the sound emitted directly from the auxiliary tail pipe without passing through the silencing space.

  Therefore, as a means for reducing the noise of the hermetic compressor due to the sound emitted from these suction mufflers, a tubular connector made of a flexible material is used for the suction pipe communicating with the inside and outside of the sealed container and the suction port of the suction muffler. There is an example in which sound is not emitted from the inhalation muffler (see, for example, Patent Document 4).

  FIG. 6 is a schematic cross-sectional view of a suction muffler of a conventional hermetic compressor described in Patent Document 4.

  As shown in FIG. 6, a suction muffler 101 of a conventional hermetic compressor described in Patent Document 4 is molded with a resin such as PBT, and a muffler body 105 that forms a muffler space 103, and a muffler body 105 And a tubular connector 109 made of a flexible material.

  The tubular connector 109 is elastically formed on the inner wall surface of the sealed container 111 so that one end communicates with the suction port 107 and the other end surrounds the opening of the suction pipe 113 communicating with the inside and outside of the container provided in the sealed container 111. It is pressed to come into contact.

  The suction muffler 101 is sandwiched and fixed by a valve plate 119 attached to an end surface of a cylinder 117 forming the compression chamber 115 and a cylinder head 121 surrounding the valve plate 119, and is provided on the valve plate 119. It communicates with the suction hole 123.

  The suction hole 123 is opened and closed by a suction valve 125.

  In the hermetic compressor of Patent Document 4 configured as described above, since the suction pipe 113 and the suction port 107 of the suction muffler 101 are directly connected by the tubular connector 109, the suction path is formed. The refrigerant gas (not shown) returned from the cycle (not shown) is supplied directly to the suction muffler 101 via the tubular connector 109 without being opened in the sealed container 111. Thereafter, the refrigerant gas released into the suction muffler 101 is sucked into the compression chamber 115. Therefore, mixing of high-temperature refrigerant gas flowing inside the sealed container 111 can be prevented, and the mass flow rate of refrigerant gas finally sucked into the compression chamber 115 can be increased.

  Further, since the sound generated when the refrigerant gas is sucked from the suction port 107 is not radiated, the noise of the hermetic compressor can be reduced.

JP-T-2001-504189 JP-A-9-324754 Japanese Utility Model Publication No. 3-24874 Special table 2005-520083 gazette

  However, in the conventional configuration described in Patent Document 4, when the refrigerant gas is sucked into the compression chamber 115 due to the reciprocating motion of a piston (not shown), the refrigerant gas generated by opening and closing the suction valve 125 is reduced. The pulsating component is transmitted into the suction muffler 101. However, among the pulsation components of the refrigerant gas, the pulsation component of the refrigerant gas in the low frequency region where the energy is large cannot be sufficiently attenuated in the volume of the sound deadening space 103, and is directly transmitted to the refrigeration apparatus through the suction path. However, there has been a problem that the vibration of the piping of the refrigeration apparatus is amplified to increase the noise.

  Further, in the conventional configuration described in Patent Document 4, since the suction path communicates with the tubular connector 109, the flow resistance of the refrigerant gas increases, suction loss occurs, and volume efficiency decreases. Had.

  The present invention solves the above-described conventional problems, and reduces noise of the hermetic compressor and reduces flow path resistance by reducing the radiated sound from the suction muffler generated when the refrigerant gas is sucked. Accordingly, an object of the present invention is to provide a hermetic compressor with high volumetric efficiency.

In order to solve the above-described conventional problems, a hermetic compressor according to the present invention houses an electric element and a compression element driven by the electric element in a hermetic container, encloses a refrigerant, and further A suction pipe connected to the refrigeration apparatus is provided in the container so that one end of the suction pipe opens into the sealed container, and the compression element includes a block that forms a compression chamber, a piston that reciprocates in the compression chamber, A suction valve disposed at an end of the compression chamber and a suction muffler communicating with the compression chamber are provided, and the suction muffler has a first silencing space and a second silencing space partitioned by a partition wall. A muffler body that forms a silenced space, a communication pipe that communicates the silenced space and the compression chamber via the suction valve, a first tail pipe and a second pipe that communicate between the closed container space and the silenced space With tailpipe The first tail pipe is provided with a first suction port at one end of the first tail pipe adjacent to the opening of the suction pipe to the closed container space, and the other end of the first tail pipe is provided with the first silencer. A first discharge port that opens in the space is provided, and further, a second suction port that communicates with the space in the sealed container is provided at one end of the second tail tube, and the other end of the second tail tube A second discharge port that opens to the second silencing space is provided .

  With this configuration, since the first tail pipe and the second tail pipe communicate with the silencing space, the radiated sound generated when the refrigerant gas is sucked can be attenuated by the silencing space.

  Furthermore, since the conventional suction muffler with only one tail pipe is provided with two tail pipes, the first tail pipe and the second tail pipe, the cross-sectional area of each tail pipe is reduced. When sound is radiated from the first suction port and the second suction port, the radiated sound can be effectively attenuated by the channel resistance of the first tail tube and the second tail tube.

  Further, the first suction port is close to the opening of the suction pipe to the space in the sealed container, so that the low-temperature and high-density refrigerant returned from the refrigeration apparatus is efficiently introduced into the compression chamber through the suction muffler. Furthermore, the second tail pipe compensates for the shortage of refrigerant gas caused by reducing the cross-sectional area of the first tail pipe in the conventional suction muffler having only one tail pipe. be able to.

  The hermetic compressor according to the present invention includes a first tail pipe and a second tail pipe for introducing refrigerant gas into the muffler body in the suction muffler, so that the radiated sound from the suction muffler generated when refrigerant gas is sucked can be obtained. The volume efficiency can be improved by effectively reducing the noise of the hermetic compressor and efficiently sucking the refrigerant from the first tail pipe and the second tail pipe.

1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. Sectional drawing of the principal part of the hermetic compressor in the first embodiment Vertical section of a conventional hermetic compressor Cross section of the main part of the suction muffler of the conventional hermetic compressor Schematic sectional view of different conventional hermetic compressors Furthermore, a schematic sectional view of the suction muffler of a different conventional hermetic compressor

According to a first aspect of the present invention, an electric element and a compression element driven by the electric element are accommodated in a sealed container, and a refrigerant is sealed. Further, an intake pipe connected to a refrigeration apparatus is provided in the sealed container. One end of the compression chamber is provided so that one end thereof opens into the sealed container, the compression element includes a block that forms a compression chamber, a piston that reciprocates in the compression chamber, and a suction valve that is disposed at an end of the compression chamber. A suction muffler that communicates with the compression chamber, the muffler body that forms a silencing space having a first silencing space and a second silencing space that are partitioned by a partition wall, and the suction valve A communication pipe that communicates the silencing space and the compression chamber via a first tail pipe and a second tail pipe that communicate with the space inside the sealed container and the silencing space. At one end, the suction pipe First an inlet provided Rutotomoni adjacent the opening to the closed container space, the other end of the first tail pipe, a first discharge port open to the first silencing space provided, further, the first one end of the two-tail tube, the second intake port is provided Rutotomoni for communicating the closed container space, the other end of the second tail pipe, provided with a second discharge port open to the second silencing space Is.

  With this configuration, since the first tail pipe and the second tail pipe communicate with the silencing space, the radiated sound generated when the refrigerant gas is sucked can be attenuated by the silencing space. Furthermore, in contrast to a conventional inhalation muffler equipped with only one tail pipe, by providing two tail pipes, a first tail pipe and a second tail pipe, the intubation of each of the first and second tail pipes is achieved. The area can be reduced.

  Therefore, when sound is radiated from the first suction port and the second suction port, the radiated sound can be effectively attenuated by the flow path resistance of the first tail tube and the second tail tube, The noise of the hermetic compressor can be reduced.

  In addition, by bringing the first suction port of the first tail pipe close to the opening of the suction pipe, the low-temperature and high-density refrigerant returned from the refrigeration apparatus is efficiently introduced into the compression chamber through the suction muffler. Furthermore, since the second tail pipe can compensate for the decrease in the refrigerant suction amount due to the reduction in the cross-sectional area in the pipe, it is possible to suppress the decrease in volume efficiency or improve the volume efficiency. .

  According to a second aspect of the invention, in the hermetic compressor of the first aspect, the amount of refrigerant gas introduced from the first tail pipe to the communication pipe via the muffler space is changed from the second tail pipe to the communication pipe. It is configured to be larger than the amount of refrigerant gas introduced into the.

With this configuration, the low-temperature and high-density refrigerant gas introduced from the first tail pipe is mainly introduced into the compression chamber, and the refrigerant gas corresponding to the shortage of the first tail pipe suction amount is supplied to the second tail pipe. It can control to introduce into a compression chamber from a tail tube. As a result, a large amount of high-temperature and low-density refrigerant gas heated in the sealed container flows from the second tail pipe into the compression chamber, and the temperature of the refrigerant gas in the compression chamber is prevented from excessively rising. can do. Therefore, in addition to the effects described in the first invention, the volume efficiency can be further effectively improved.

  According to a third aspect of the present invention, in the hermetic compressor of the first or second aspect, the in-pipe cross-sectional area of the first tail pipe is formed larger than the in-pipe cross-sectional area of the second tail pipe.

  With this configuration, it is possible to reduce the amount of refrigerant gas heated at a high temperature in the sealed container that is sucked into the suction muffler body from the second tail pipe and having a low density, and the refrigerant gas in the compression chamber is reduced. Extreme heating can be prevented. As a result, in addition to the effects described in the first or second invention, the volume efficiency can be further improved effectively. Moreover, the cross-sectional area in the pipe of the second tail pipe can be kept small, and the radiated sound from the second tail pipe can be attenuated. Therefore, resonance of the sealed container due to this radiated sound can be suppressed, and noise of the compressor can be reduced.

  According to a fourth invention, in the hermetic compressor according to any one of the first to third inventions, the electric element is inverter-driven at a plurality of operating frequencies.

  Thus, by using a plurality of primary resonance modes generated by the combination of the first and second tail pipes and the silencing space, volume efficiency can be improved by resonance supercharging at a plurality of operating frequencies, It is possible to provide a hermetic compressor with less variation in efficiency due to different operating frequencies.

  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 hermetic compressor according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a main part of the hermetic compressor according to the first embodiment.

  1 and 2, the hermetic compressor stores oil 203 in the inner bottom portion of the hermetic container 201 and encloses, for example, hydrocarbon-based R600a having a low global warming potential as the refrigerant gas 205. ing.

  The sealed container 201 is formed by drawing a steel plate and includes a suction pipe 207 in a part of the peripheral wall. The suction pipe 207 has an opening 209 communicating with the inside of the sealed container 201 at one end, and the other end is connected to a low-pressure side pipe (not shown) of the refrigeration apparatus.

  Further, a compressor body 215 having a compression element 211 and an electric element 213 for driving the compression element 211 is elastically supported in the sealed container 201 by a suspension spring 217 and stored in the sealed container 201. Has been.

  The compression element 211 includes a crankshaft 219, a block 221, a piston 223, a connection means 225, and the like. Here, the crankshaft 219 includes an eccentric shaft 227 and a main shaft 229, and an oil supply mechanism 231 including a spiral groove is provided on the surface of the main shaft 229. The oil supply mechanism 231 communicates from the lower end of the main shaft 229 immersed in the oil 203 to the upper end of the eccentric shaft 227.

The electric element 213 is placed below the block 221 with a stator 233 fixed by bolts (not shown) and a rotor 235 that is shrink-fitted and fixed to the main shaft 229 and coaxial with the axis of the stator 233. It consists of The electric element 213 is connected to an external inverter drive circuit (not shown), and is inverter-driven at a plurality of operation frequencies as is well known.

  The block 221 is integrally formed with a cylinder 239 that forms a compression chamber 237, and is further provided with a bearing portion 241 that rotatably supports the main shaft 229.

  In addition, a valve plate 243, a suction valve 245, and a cylinder head 247 are fastened to the end face of the cylinder 239 so as to seal the end face of the cylinder 239 with a head bolt 249, and the suction muffler 251 is further tightened. The valve plate 243 and the cylinder head 247 are sandwiched and fixed. Here, the valve plate 243 includes a suction hole 253 and a discharge hole (not shown), and the suction valve 245 opens and closes the suction hole 253.

  The suction muffler 251 is molded mainly from a synthetic resin such as PBT to which glass fiber is added, and a muffler body 259 in which a first tail pipe 255 and a second tail pipe 257 are integrally formed to guide the refrigerant gas 205 into the suction muffler 251. And a cover 263 provided with a communication pipe 261 that guides the refrigerant gas 205 in the suction muffler 251 into the compression chamber 237. The muffler main body 259 and the cover 263 are combined and integrated to form a first silencing space 265 and a second silencing space 267 partitioned by a partition wall 251a.

  The first tail tube 255 includes a first suction port 269 that opens into the space inside the sealed container 201 and a first discharge port 271 that opens near the bottom of the first silencing space 265. An oil discharge hole 273 is provided at the bottom of the first silencing space 265 near the first discharge port 271.

  The second tail pipe 257 includes a second suction port 275 that opens into the space inside the sealed container 201 and a second discharge port 277 that opens into the second silencing space 267. An oil discharge hole 279 is provided at the bottom of the second silencing space 267.

  Here, the cross-sectional area of the first tail pipe 255 is formed larger than the cross-sectional area of the second tail pipe 257, and the suction muffler 251 is formed in the opening 209 of the suction pipe 207 at the first tail pipe 255. The first suction port 269 is disposed so that the openings face each other.

  Further, the second discharge port 277 of the second tail pipe 257 opens at a position away from the first discharge port 271 of the first tail pipe 255 with respect to the suction opening 261a of the communication pipe 261, and the opening thereof. Is also set to a direction substantially perpendicular to the suction opening 261a of the communication pipe 261.

  One end of the communication pipe 261 opens into the first silencing space 265, and the other end is connected to the suction hole 253 and communicates with the compression chamber 237 via the suction valve 245.

  The operation and action of the hermetic compressor configured as described above will be described below.

  The hermetic compressor causes a current to flow through the stator 233 to generate a magnetic field, and rotates the rotor 235 fixed to the main shaft 229. As a result, the crankshaft 219 rotates and the piston 223 reciprocates in the cylinder 239 via the connecting means 225 that is rotatably attached to the eccentric shaft 227. Then, the reciprocating motion of the piston 223 causes the refrigerant gas 205 to be sucked into the compression chamber 237 via the suction muffler 251, compressed, and then discharged to a refrigeration apparatus (not shown).

  Next, the suction stroke of the hermetic compressor will be described.

  When the piston 223 operates in a direction in which the volume in the compression chamber 237 increases from the top dead center, the refrigerant gas 205 in the compression chamber 237 expands. As a result, the pressure in the compression chamber 237 decreases. When the pressure falls below the suction pressure, the suction valve 245 starts to open due to the difference between the pressure in the compression chamber 237 and the pressure in the suction muffler 251.

  The low-temperature refrigerant gas 205 returned from the refrigeration apparatus (not shown) is once released from the suction pipe 207 into the sealed container 201, and then in parallel from the first suction port 269 and the second suction port 275. It is inhaled and opened to the first silencing space 265 and the second silencing space 267 via the first tail tube 255 and the second tail tube 257, respectively. The opened refrigerant gas 205 flows into the compression chamber 237 through the communication pipe 261.

  Thereafter, when the operation of the piston 223 turns from the bottom dead center in a direction in which the volume in the compression chamber 237 decreases, the refrigerant gas 205 in the compression chamber 237 is compressed. As a result, the pressure in the compression chamber 237 increases, and the suction valve 245 is closed due to the difference between the pressure in the compression chamber 237 and the pressure in the suction muffler 251.

  Here, in the suction muffler 251, the first discharge port 271 is disposed and formed near the bottom of the first silencer space 265, one end of the communication pipe 261 is opened to the first silencer space 265, and further from the first discharge port 271. An inner wall surface of the muffler main body 259 is formed so as to guide the refrigerant gas 205 from the lower side of the first silencing space 265 to the suction opening 261a of the communication pipe 261.

  Therefore, the refrigerant gas 205 released from the first discharge port 271 is smoothly guided to the communication pipe 261 along the curved inner wall surface below the first silencing space 265.

  On the other hand, since the second discharge port 277 is open to the second silencing space 267, the refrigerant gas 205 released from the second discharge port 277 flows into the first silencing space 265 and enters the first silencing space 265. After being mixed with the refrigerant gas 205 staying in the pipe, it is guided to the communication pipe 261. Moreover, the direction of the opening of the second discharge port 277 is a direction that collides with the top surface of the cover 263 of the suction muffler 251, and further communicates with the first silencing space 265 via the partition wall 251a. Since the position is farther from the suction opening 261a of the communication pipe 261 than the distance of the first discharge port 271, the flow path resistance is large with respect to the flow of the refrigerant gas 205.

  Furthermore, since the cross-sectional area of the first tail pipe 255 is larger than the cross-sectional area of the second tail pipe 257, the amount of the refrigerant gas 205 sucked into the first silencing space 265 from the first tail pipe 255 is The amount of refrigerant gas 205 sucked into the second silencing space 267 from the second tail pipe 257 is greater than the amount.

  Therefore, the main suction path of the refrigerant gas 205 is a path from the first tail pipe 255 to the communication pipe 261, and the first suction port 269 is installed in the vicinity of the opening 209 of the suction pipe 207. As a result, the low-temperature and high-density refrigerant gas 205 returned from the refrigeration apparatus (not shown) through the suction pipe 207 enters the compression chamber 237 via the first tail pipe 255 serving as the main suction path. The volumetric efficiency can be improved.

In other words, the refrigerant gas 205 deficient in the suction amount of the first tail pipe 255 is sucked into the second silencing space 267 from the second tail pipe 257, but as described above, the refrigerant pipe 205 is communicated from the second tail pipe 257 to the communication pipe 261. In addition to the fact that the cross-sectional area in the pipe is smaller than that of the first tail pipe 255, the suction path leading to the pipe has a large flow path resistance due to the configuration such as the flow direction and the flow distance. Therefore, it is possible to suppress a large amount of the refrigerant gas 205 having a low density at a high temperature, which is retained in the sealed container 201 and heated by the heat generated by the electric element 213, from flowing into the compression chamber 237. As a result, it is possible to prevent the temperature of the refrigerant gas 205 sucked into the compression chamber 237 from rising extremely, and to suppress a decrease in volumetric efficiency.

  Further, the suction muffler 251 disposed in the vicinity of the electric element 213 is formed of a resin having a low thermal conductivity, so that the temperature of the refrigerant gas 205 passing through the suction muffler 251 is reduced by the heat generation of the electric element 213 and the like. Can be affected and prevented from rising. As a result, the refrigerant gas 205 having a high density can be sucked into the compression chamber 237, and the volume efficiency can be improved.

  Here, conventionally, it is known that volumetric efficiency is improved by resonance supercharging using a primary resonance mode generated by a combination of a tail tube and a silencing space. For example, when the tail pipe is one general suction muffler, the primary resonance mode generated by the combination of the tail pipe and the muffler space generates only one frequency. For this reason, the primary resonance mode generated by the combination of the tail tube and the silencing space is tuned to the operation frequency that requires the highest efficiency.

  Since the suction muffler 251 of the first embodiment includes the two tail pipes of the first tail pipe 255 and the second tail pipe 257, the primary resonance mode generated by the combination with the sound deadening spaces 265 and 267 also includes a plurality of primary resonance modes. Can be generated at a frequency.

  Accordingly, when the inverter is driven at a plurality of operating frequencies by an external inverter driving circuit (not shown) as in the hermetic compressor of the first embodiment, the two tail pipes are used for these operating frequencies. By tuning the primary resonance mode generated by each combination with the silencing space, the volumetric efficiency at each operating frequency can be improved, and a hermetic compressor that reduces the fluctuation in efficiency due to the change control of the operating frequency is provided. Can be provided.

  Next, the flow operation of the oil 203 will be described.

  The oil 203 stored in the bottom of the sealed container 201 is conveyed to the upper portion of the compression element 211 by the oil supply mechanism 231 that uses the centrifugal force obtained by the rotation of the crankshaft 219 and the viscous friction force generated in the sliding portion. The The oil 203 conveyed to the compression element 211 is scattered from the upper end of the crankshaft 219 after lubricating the sliding portions such as the crankshaft 219 and the bearing portion 241.

  The oil 203 scattered in the inner space of the sealed container 201 falls on the sliding portions of the piston 223 and the cylinder 239 and lubricates the sliding portions, and a part of the oil 203 adheres to the inner surface of the sealed container 201 and slides. The hermetic compressor is cooled by radiating the heat accompanying the movement to the outside through the hermetic container 201.

  Further, a part of the oil 203 scattered in the space in the sealed container 201 is sucked together with the refrigerant gas 205 from the first suction port 269 and the second suction port 275 of the suction muffler 251.

  The oil 203 sucked together with the refrigerant gas 205 is opened to the first silencing space 265 and the second silencing space 267 having large volumes through the first suction port 269 and the second suction port 275, and the flow velocity of the refrigerant gas 205 is reached. Is reduced from the refrigerant gas 205. And most of the separated oil 203 falls to the bottom of the first silencing space 265 and the second silencing space 267 by gravity.

The dropped oil 203 is sucked into the suction muffler 251 through an oil discharge hole 273 provided at the bottom of the first silencing space 265 near the first discharge port 271 and an oil discharge hole 279 provided at the bottom of the second silencing space 267. Are discharged to the outside. By this discharge, the oil 203 staying in the suction muffler 251 can be reduced. As a result, the volume of the first silencing space 265 and the second silencing space 267 during operation is secured, and the noise of the hermetic compressor can be stably reduced.

  Next, the noise of the hermetic compressor will be described.

  In a general hermetic compressor, noise is generated due to opening and closing of the suction valve 245 when the refrigerant gas 205 is sucked into the compression chamber 237 due to the reciprocating motion of the piston 223. Therefore, the sound radiated into the sealed container 201 is attenuated by the suction muffler, and the noise of the hermetic compressor is reduced.

  Here, in a general hermetic compressor equipped with a suction muffler equipped with only one tail pipe, as a means for improving volumetric efficiency, the cross-sectional area of the tail pipe is increased to reduce the suction loss of the refrigerant gas. A means for reducing is conceivable.

  However, when the cross-sectional area of the tail pipe is increased, the attenuation effect by the suction muffler is reduced accordingly, and the noise of the hermetic compressor may be deteriorated.

  However, as in the first embodiment, the first muffler 251 includes the first tail tube 255 and the second tail tube 257, so that the first tail tube 255 is compared with the case where only one tail tube is provided. Even if the cross-sectional area in the pipe of the second tail pipe 257 is reduced, the refrigerant gas 205 can be sucked in a necessary and sufficient amount, and both volume efficiency and noise can be reduced.

  As described above, the hermetic compressor according to the present invention can increase the refrigerant gas suction efficiency, improve the efficiency of the hermetic compressor, and reduce noise, so that the air conditioner is not limited to an electric refrigerator for home use. Widely applicable to vending machines and other refrigeration equipment.

201 Sealed container 205 Refrigerant gas 207 Suction pipe 209 Opening 211 Compression element 213 Electric element 221 Block 223 Piston 237 Compression chamber 245 Suction valve 251 Suction muffler 255 First tail pipe 257 Second tail pipe 259 Muffler main body 261 Communication pipe 265 First Silencing space 267 Second silencing space 269 First inlet 275 Second inlet

Claims (4)

In the sealed container, the electric element and the compression element driven by the electric element are accommodated and the refrigerant is enclosed,
Furthermore, the closed container is provided with a suction pipe connected to a refrigeration apparatus so that one end of the intake pipe opens into the closed container,
The compression element includes a block that forms a compression chamber, a piston that reciprocates in the compression chamber, a suction valve that is disposed at an end of the compression chamber, and a suction muffler that communicates with the compression chamber. ,
A muffler body that forms a silencing space having a first silencing space and a second silencing space partitioned by a partition wall, and a communication pipe that communicates the silencing space and the compression chamber via the suction valve. And a configuration comprising a first tail pipe and a second tail pipe communicating with the space in the sealed container and the sound deadening space,
One end of the first tail pipe, the first inlet port close to the opening to the closed container space of the suction pipe is provided Rutotomoni, the other end of the first tail pipe, the first silencing space Provide a first discharge port that opens,
Further, the one end of the second tail pipe, the second intake port is provided Rutotomoni for communicating the closed container space, the other end of the second tail pipe, the second ejection opening into the second silencing space A hermetic compressor with an outlet . The refrigerant gas amount introduced from the first tail pipe to the communication pipe via the noise reduction space is configured to be larger than the refrigerant gas amount introduced from the second tail pipe to the communication pipe. The hermetic compressor described in 1. The hermetic compressor according to claim 1 or 2, wherein a cross-sectional area of the first tail pipe is larger than a cross-sectional area of the second tail pipe. The hermetic compressor according to any one of claims 1 to 3, wherein the electric element is inverter-driven at a plurality of operating frequencies.