JPH05164075A - Two cylinder type rotary compressor - Google Patents

Abstract

PURPOSE:To increase proper oscillation frequency of a shaft system, and reduce noise caused by shaft vibration by forming a part of a gas passage to introduce gas compressed in a cylinder into a silencer arranged on the sub bearing side, by a means to bring a plate into close contact with a main bearing to support a crankshaft. CONSTITUTION:Rollers 10a and 10b fitted in eccentric parts 3a and 3b having a different phase by 180 are put in eccentric turning motion in respective cylinders 6 and 8 of the first and the second pump parts, and refrigerant gas is compressed alternately, and is delivered from delivery ports 5d and 9d arranged respectively in a main bearing 5 and a sub bearing 9. The refrigerant gas delivered from the delivery port 5d of the first pump part is released into a gas passage formed by bringing the main bearing 5 and a plate 17 into close contact with each other, and in succession, it is passed through the first communicating passage 17 from the main bearing side to the sub bearing side, and is introduced into a common use silencer 20 formed of the sub bearing 9 and a cover 19, so that noise can be eliminated. The refrigerant gas, which is compressed in the second pump part and is delivered from the delivery port 9d, is also introduced directly into the silencer 20, so that the noise can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-cylinder rotary compressor, which is used in, for example, a refrigerating cycle for a refrigerator or an air conditioner, and has a particularly low noise and high reliability. It is about.

[0002]

2. Description of the Related Art As a general two-cylinder type rotary compressor, for example, a multi-cylinder rotary compressor disclosed in Japanese Patent Laid-Open No. 2-230994 is known. This conventional two-cylinder type rotary compressor will be described with reference to FIG. FIG. 6 is a vertical sectional view of a conventional two-cylinder type rotary compressor. In the two-cylinder type rotary compressor shown in FIG. 6, an electric motor section and a compression mechanism section are housed in a closed container 1. The electric motor unit is composed of a stator 2 fixed in the closed container 1 by shrink fitting, and a rotor 4 fixed to the crankshaft 3A. The compression mechanism section is provided with two sets of compression elements (hereinafter referred to as pump sections) mainly including the first cylinder 6A fixed by welding or the like in the closed container 1.

Among them, the first pump portion rotates the main bearing 5A supporting the crankshaft 3A, the first cylinder 6A, the partition plate 7A, the roller 10a fitted in the eccentric portion 3a of the crankshaft 3A, and the roller 10a. It consists of vanes (not shown) that follow and reciprocate. The second pump portion includes the partition plate 7A, the second cylinder 8A, the crankshaft 3
Auxiliary bearing 9A for supporting A, eccentric portion 3b of crankshaft 3A
And a vane (not shown) that reciprocates following the rotation of the roller 10b.

The compressed gas in the first cylinder 6A is
After being discharged to the first discharge silencer 13a formed by the first discharge cover 12a, it is discharged into the closed container 1. In addition, the compressed gas in the second cylinder 8A is the same as the gas in the first cylinder 6A.
It is discharged into the closed container 1 through the second discharge silencer 13b formed by. The first discharge cover 12
a, main bearing 5A, first cylinder 6A, partition plate 7A, second
The elements of the cylinder 8A, the sub bearing 9A, and the second discharge cover 12b are fixed by mounting bolts (not shown).

In the two-cylinder type rotary compressor having such a structure, the discharge gas noise emitted from the first cylinder 6A and the second cylinder 8A is reduced by the first discharge silencer 13a and the second discharge silencer 13b, respectively. The noise was heard and the noise of the compressor was reduced.

[0006]

In the conventional two-cylinder type rotary compressor, the first discharge silencer 13a is used.
Since the first discharge cover 12a that forms the rotor is provided, in order to prevent the first discharge cover 12a and the winding portion of the stator 2 of the electric motor portion from coming into contact with each other and short-circuiting, the rotor 4 is It was necessary to separate the stator 2 from the pump portion and fix it to the tip side of the crankshaft 3A to move the stator 2 away.
Therefore, the natural frequency of the shaft system is lowered, and further, the whirling amount of the tip end portion of the crankshaft 3A is increased, resulting in an increase in noise due to the shaft vibration and a decrease in reliability in the bearing portion.

The present invention has been made in order to solve the above-mentioned problems of the prior art. It is a highly reliable two-cylinder which reduces noise due to shaft vibration during operation and reduces whirling at the tip of the crankshaft. It is an object of the present invention to provide a rotary compressor of the type.

[0008]

In order to achieve the above object, the structure of a two-cylinder type rotary compressor according to the present invention has a structure in which a motor unit and a compression mechanism unit composed of two compression elements are provided in a closed container. And a rotational force of the electric motor is transmitted to a compression mechanism portion by a crankshaft, and the refrigerant gas is alternately compressed by two compression elements. In a two-cylinder type rotary compressor configured by superposing respective elements of a bearing, a first cylinder, a partition plate, a second cylinder, and a sub-bearing, a flat plate closely attached to the electric motor side of the main bearing, and a motor of the main bearing. On the main bearing side gas passage, which is provided on the side of the auxiliary bearing and communicates with the discharge portion of the gas compressed in the first cylinder and is covered by the flat plate, and is provided on the side opposite to the electric motor of the auxiliary bearing and is compressed in the second cylinder. The discharged gas And a silencer in communication with the,
A communication passage that connects the main bearing side gas passage and the sub bearing side silencer is provided, and the sub bearing side silencer is 2
A common silencer is configured for each compression element.

More specifically, the gas passage on the main bearing side includes an arcuate groove in a limited range which connects the valve peripheral region of the discharge portion and the communication passage leading to the silencer on the sub bearing side. That is, the arcuate groove communicating with the valve portion provided on the electric motor side of the main bearing is set so as not to be the gas passage connected for 360 degrees around the crankshaft.

[0010]

According to the present invention, a part of the gas passage for guiding the gas compressed in the first cylinder to the silencer provided on the auxiliary bearing side is formed in the main bearing by means of bringing the flat plate into close contact with the main bearing from the electric motor side. Therefore, it is sufficient for the motor part to keep the plate thickness dimension of the flat plate that is in close contact with the main bearing away from the pump part, and it becomes possible to install the rotor of the motor in the vicinity of the pump part. The natural frequency can be increased, and noise due to shaft vibration can be reduced. In addition, since the whirling of the tip of the crankshaft is reduced, it is possible to prevent partial contact in the bearing portion and improve the reliability of the bearing portion.

Further, an arc-shaped groove formed on the electric motor side of the main bearing and serving as a passage for the refrigerant gas is provided around the crankshaft 36.
By making the structure not connected for 0 degree, it is possible to prevent the generation of resonance sound in the groove. This is because when the arcuate groove communicates with the entire circumference around the crankshaft,
There is a phenomenon that the resonance frequency corresponding to the wavelength of the circumferential length of the groove coincides with the frequency near 1 kHz, which is the main component of the discharge gas sound, and the silencing effect of the frequency disappears. This phenomenon can be prevented.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a second embodiment according to the present invention.
A longitudinal sectional view of the cylinder type rotary compressor, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a sectional view taken along the line BB of FIG.
FIG. 4 is an exploded perspective view of the main parts of the compression mechanism section of FIG. First, referring to FIG.
The structure of a cylinder type rotary compressor is shown. In the figure, the same reference numerals as those in FIG. 6 indicate components equivalent to those in the conventional technique.

In the two-cylinder rotary compressor shown in FIG. 1, an electric motor part and a compression mechanism part composed of two pump parts directly connected to the electric motor by a crankshaft 3 are housed in a closed container 1. There is. The electric motor unit is composed of a stator 2 fixed to the closed container 1 by shrink fitting, and a rotor 4 fitted with a crankshaft 3. The compression mechanism section has a two-cylinder compression element (hereinafter referred to as a pump section),
The first pump portion is a main bearing 5 that supports the crankshaft 3,
The second cylinder is composed of the first cylinder 6 and the partition plate 7, and the second pump part is composed of the partition plate 7, the second cylinder 8 and an auxiliary bearing 9 supporting the crankshaft. And
The main bearing 5 is fixed to the closed container 1 by welding or the like.

The crankshaft 3 has two eccentric portions 3a and 3b which are 180 ° out of phase with each other, and the rollers 10a and 10b relating to the two rolling pistons fitted in these eccentric portions 3a and 3b. However, with the rotation of the crankshaft 3, the first cylinder 6 and the second cylinder 8 are eccentrically rotated. These rollers 10a, 1
Following the rotation of 0b, the vanes 11a and 11b reciprocate in the cylinders 6 and 8 to alternately compress the refrigerant gas.

The characteristic part of the configuration of this embodiment will be described. In the figure, 5d is a discharge port for gas compressed in the first cylinder 6, which is provided on the electric motor side of the main bearing 5.
e is a discharge path related to the valve surrounding area of the discharge port 5d, and 9d
Is a discharge port of the gas compressed in the second cylinder 8 provided on the side opposite to the electric motor of the auxiliary bearing 9, 14 is a valve retainer of a discharge valve for opening and closing the discharge port 5d, and 15 is a discharge passage 5e. An arc-shaped groove communicating with the reference numeral 16 is a flat plate brought into close contact with the main bearing 5 on the electric motor side, and 17 is a groove 15 on the main bearing side and the sub bearing 9
The first communication passage connecting the silencer 20 on the side, the second communication passage 18 connecting the silencer 20 and the internal space of the electric motor side closed container, 19 the cover of the auxiliary bearing 9, 20 the auxiliary bearing 9
A silencer 21 provided on the side opposite to the electric motor is a valve retainer for a discharge valve that opens and closes the discharge port 9d. Flat plate 16
Is adhered to the electric motor side of the main bearing 5 to cover the discharge passage 5e and the groove 15 on the main bearing 5 side to form a gas passage.

Of the above pump parts, the refrigerant gas compressed by the first pump part is discharged through the discharge port 5d into the gas passage formed by the main bearing 5 and the flat plate 16 being in close contact with each other. .. As shown by the arrow in FIG. 1, this refrigerant gas passes from the main bearing side to the sub bearing side through the first communication passage 17 (the broken line portion in the figure) and is shared by the sub bearing 9 and the cover 19. After being guided into the silencer 20 and being silenced, it is discharged to the electric motor side through the second communication passage 18. Also, the second
The refrigerant gas compressed by the pump section is discharged from the discharge port 9d of the auxiliary bearing 9 to the common silencer 20, is silenced, and then is discharged into the closed container 1 through the second communication passage 18. ..

The above silencer structure will be described in more detail with reference to FIGS. 2 is a sectional view taken along the line AA of FIG. 1, and the refrigerant gas passage on the main bearing side will be described with reference to FIG. The groove 15 has an arc shape and is provided on the electric motor side of the main bearing 5. Reference numeral 14 denotes a valve retainer of a discharge valve (not shown), which discharges the refrigerant gas compressed by the first pump portion from the discharge port 5d shown by the broken line and flows through the discharge passage 5e and the groove 15. , The first communication passage 17
From the sub bearing to the silencer 20. Here, the configuration of the first communication passage 17 will be described with reference to FIG.

FIG. 4 is a perspective view of the main parts of the compression mechanism section of FIG. In the figure, the same reference numerals as those in FIG. 1 indicate the same parts, and the description thereof will be omitted. Since the compression mechanism portion is configured by stacking the main bearing 5, the first cylinder 6, the partition plate 7, the second cylinder 8, and the sub bearing 9, the through holes 5a, 6a, 7a, provided in the respective parts, 8
The first communication passage 17 is formed by communicating the a and 9a. In FIG. 1, the shared silencer 20 is formed by the close contact between the auxiliary bearing 9 and the cover 19. The shared silencer will be described with reference to FIG.

FIG. 3 is a sectional view taken along the line BB of FIG.
In the present embodiment, the shared silencer 20 includes three chambers 20.
a, 20b, 20c, the refrigerant gas compressed by the first pump portion is supplied from the first communication passage 17 to the chamber 20.
When reaching the c, the sound is silenced when passing through the chambers 20b and 20a and being discharged from the second communication passage 18 into the closed container 1 by the sound absorbing effect of the expansion type and the resonance type. In addition, the valve retainer 21 and a second valve installed under the valve (not shown)
The refrigerant gas discharged from the discharge port 9d of the pump portion is also stored in the chamber 20.
After passing through c, 20b, and 20a to be silenced, it is discharged from the second communication passage 18. In the two-cylinder rotary compressor, the gas compressed by the first pump section and the gas compressed by the second pump section are alternately discharged, so the silencer on the auxiliary bearing side is a one-cylinder type compressor with a half volume. Even if the volume is the same as that of the silencer used for, it can be sufficiently shared.

According to this embodiment, since the discharge passage 5e and the groove 15 provided in the main bearing 5 are in close contact with each other by the flat plate 16, the main bearing side gas passage is formed and the position of the stator of the electric motor section is also increased. Can be brought close to the compression mechanism,
The fixed position of the rotor 4 fixed to the crankshaft 3 can be brought close to the compression mechanism portion. Therefore, the natural frequency of the shaft system increases, and the noise due to the shaft vibration does not increase. Furthermore, the amount of whirling at the tip of the crankshaft is reduced, and the reliability of the bearing is improved. Further, by bringing the fixing position of the rotor 4 fixed to the crankshaft 3 closer to the pump portion, the total length of the closed container 1 is shortened, the rigidity of the closed container 1 is increased, and the noise in the high frequency band is reduced.

These effects will be described with reference to FIG. FIG. 5 is a noise spectrum diagram showing an effect of noise reduction in the two-cylinder rotary compressor of FIG. In FIG. 5, the horizontal axis represents the frequency (kHz) and the vertical axis represents the sound pressure level. The sound pressure level of the conventional two-cylinder rotary compressor is indicated by a broken line,
The two-cylinder rotary compressor of the present invention is shown by a solid line for noise comparison. As can be seen from FIG. 4, in the present invention, the shaft vibration sound in the 300 Hz band and the mechanical vibration sound in the 4000 Hz to 6000 Hz band are reduced.

Further, it is preferable that the arc-shaped groove 15 which is opened to the discharge portion provided on the electric motor side of the main bearing is not connected for the entire circumference 360 degrees around the crankshaft 3.
When the arcuate groove 15 provided in the main bearing 5 communicates with the entire circumference around the rotation axis, a specific standing wave is likely to be generated in the channel of the groove 15, and resonance occurs in the channel to increase noise. Tend. For example, the sound velocity of the discharge gas of the refrigerant R12 is about 16
The resonance frequency is about 0 m / s, and the resonance frequency is 1 kHz when the circumference length when the arc-shaped grooves communicate with each other is about 16 cm.
It becomes z. Around 1 kHz is a band in which fluid noise due to the discharge gas is large, which is not preferable.

Although the above embodiment has been described with respect to the horizontal two-cylinder rotary compressor, the same effect can be expected for the vertical two-cylinder rotary compressor.

[0024]

As described in detail above, according to the present invention, noise due to shaft vibration during operation is reduced and
It is possible to provide a highly reliable two-cylinder type rotary compressor in which whirling at the tip of the crankshaft is reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a two-cylinder rotary compressor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along the line BB of FIG.

FIG. 4 is a perspective view showing an exploded main part of the compression mechanism section of FIG.

5 is a noise spectrum diagram showing an effect of noise reduction in the two-cylinder rotary compressor of FIG. 1. FIG.

FIG. 6 is a vertical sectional view of a conventional two-cylinder type rotary compressor.

[Explanation of symbols]

 1 Airtight Container 3 Crankshaft 5 Main Bearing 5d Discharge Port 5e Discharge Path 6 First Cylinder 7 Partition Plate 8 Second Cylinder 9 Secondary Bearing 15 Groove 16 Flat Plate 17 First Communication Passage 18 Second Communication Passage 20 Silencer

Claims (2)

[Claims] 1. A hermetically-sealed container is provided with an electric motor section and a compression mechanism section composed of two compression elements, and the rotational force of the electric motor is transmitted to the compression mechanism section by a crankshaft. The compression mechanism section alternately compresses the refrigerant gas, and the compression mechanism section is a two-cylinder structure in which elements of a main bearing, a first cylinder, a partition plate, a second cylinder, and an auxiliary bearing are superposed from the electric motor side. Type rotary compressor, a flat plate closely attached to the motor side of the main bearing, and a flat plate which is provided on the motor side of the main bearing and communicates with a discharge portion of the gas compressed in the first cylinder and is covered with the flat plate. A main bearing side gas passage, a silencer provided on the side of the sub bearing opposite to the electric motor and communicating with a discharge portion of gas compressed in the second cylinder, the main bearing side gas passage and the sub bearing side silencer. Connecting passageway Wherein the auxiliary bearing side of the silencer, 2 cylinder type rotary compressor, characterized in that to constitute a common silencer against two compression element. 2. The gas passage on the main bearing side includes an arc-shaped groove in a limited range that connects the valve surrounding region of the discharge portion and the communication passage leading to the silencer on the sub bearing side. The two-cylinder rotary compressor according to claim 1.