JPH0772549B2 - Rotary compressor - Google Patents

Description

The present invention relates to an improvement of a rotary compressor that can be used for a refrigerant compressor for refrigeration / air conditioning, other gas compressors, and the like. This is to reduce noise.

[Conventional technology]

A conventional rotary compressor will be described with reference to FIGS. 6 to 13 by taking a refrigerant compressor for refrigeration and air conditioning as an example. In the figure, reference numeral 1 denotes a hermetically sealed housing, and a discharge pipe 2 for leading out a compressed refrigerant gas therein is provided at an upper portion of the housing. A condenser 4, a throttle mechanism 5, an evaporator 6 and an accumulator 7 are sequentially connected to the discharge pipe 2 via a refrigerant pipe 3, and the accumulator 7 is connected to a space inside a cylinder in the closed housing 1 via a suction pipe 8. It communicates with 20. 9
Is an inlet of the suction pipe 8 in the accumulator 7. The gas refrigerant sucked into the cylinder inner space 20 from the inlet portion 9 through the suction pipe 8 is compressed, and the discharge port 34 and the discharge valve
After being discharged to the discharge cavity 13 via 42, it is led out to the space portion 14 in the closed housing 1, passes around the motor 11, and is discharged from the discharge pipe 2 to the outside of the closed housing 1. There is. Reference numeral 12 is a crankshaft, and 15 is lubricating oil stored in the bottom of the closed housing 1. Reference numeral 30 denotes a cylinder body fixed to a lower portion in the closed housing 1, and an upper bearing 40 and a lower bearing 41 for rotatably supporting the crankshaft 12 are fixed to the upper and lower ends of the cylinder body by bolts, and the cylinder is hermetically sealed. The inner space 20 is formed. A rotor 31 is loosely fitted in the eccentric portion of the crankshaft 12 in the cylinder inner space 20, and the cylinder inner space 20 is provided in a groove provided in the cylinder body 30 with the tip of the cylinder inner space 20 on the outer peripheral surface of the rotor 31. A partition plate 32 slidably fitted so as to be pressed by is partitioned into a suction side space 20a in which the suction pipe 8 communicates and a compression side space 20b.

The discharge port 34 is adjacent to the partition plate 32 and is on the compression side space 20b.
A discharge valve 42 is attached to the discharge port 34 via a retainer 43 and a bolt 44. Reference numeral 33 denotes a notch groove provided in the cylinder 30 to secure a passage area between the discharge port 34 and the cylinder inner space 20, and the compressed gas is discharged from the notch groove 33 through the discharge port 34. ing.

In the rotary compressor having the above-described structure, the low-pressure refrigerant gas is sucked into the suction side space 20a through the suction pipe 8, and the gas sucked one rotation before is compressed in volume as the rotor 31 rotates. After being compressed in the side space 20b, it is discharged from the discharge valve 42 through the cutout groove 33 and the discharge port 34, but the cutout groove 33 and the discharge port 34 form a so-called top clearance volume. The discharge gas in (3) remains without being discharged from the discharge valve 42, and when the rotor 31 passes through the top clearance volume, it flows back into the suction side space 20a during the suction stroke. Therefore, the pressure in the cylinder inner space 20 is measured as shown in FIG. 9th
The figure shows the rotor rotation angle on the horizontal axis and the cylinder internal space pressure on the vertical axis.Since the residual compressed gas in the top clearance volume suddenly flows backward to the low pressure suction side space 20a, the pressure in the suction side space 20a There is a problem that the waveform includes vibration of high frequency components as indicated by A, and the noise of the compressor becomes large due to the influence of this pulsation.

Therefore, in order to prevent the pulsation of this high-frequency component, the top clearance volume is provided with a buffer 35 utilizing the acoustic effect as shown in FIG. 10 and FIG.
As shown in Fig. 12, in order to prevent the residual compressed gas in the top clearance volume from leaking rapidly to the low pressure suction side space 20a side, a depth of about several hundred μm from the notch groove 33 to the suction side space 20a side. It is devised that the cutting groove 36 is provided to gradually leak gas.

However, in the case shown in Figs. 10 and 11, some of the lubricating oil sucked into the cylinder during operation is buffered.
There was a problem in that the noise reduction effect could not be fully exerted if the buffer volume was filled with the lubricating oil after entering 35. On the other hand, in the case shown in FIG. 12, when the rotor 31 comes into the cutting groove 36, performance deterioration due to gas leakage is recognized as compared with the case where the rotor 31 does not have the cutting groove 36, and the leakage area is constant depending on the operating pressure condition. There was a problem that it was reduced. In addition, since the cutting depth is several hundreds of μm, it has difficulty in processing, and in order to maintain the effect under a wide range of operating pressure conditions, the depth of the cutting groove 36 is made small and its length is made long. However, this was to stop the leak timing and greatly reduce the performance.

Therefore, as shown in FIG. 13 as Japanese Patent Application No. 62-10681, the present applicant has established two notch grooves 33a, 33b forming a top clearance volume for generating a reverse flow of residual compressed gas with respect to the cylinder center φ. , .DELTA..theta. Positions are provided in the cylinder main body 30 at different positions, and pulsations having half-phase shifts are generated in the cylinder space 20 to cancel each other out to suppress the pulsations and reduce noise. This is effective when the number of revolutions is constant, but in a compressor that is driven by an inverter and whose number of revolutions varies over a wide range, it is possible to exert sufficient effects in all regions of the number of revolutions change. Can not. That is, when aiming to reduce the noise in the high speed rotation range where the noise level is high, in the low speed rotation range, the amount of gas leaking from the compression side space including the top clearance volume into the suction side space relatively increases, leading to performance degradation. .

[Problems to be Solved by the Invention]

In the above-mentioned conventional type, noise caused by rapid backflow of the residual compressed gas of the top clearance volume into the low-pressure cylinder space is accompanied by performance deterioration and processing difficulty in a wide range of rotation speed change areas. It could not be reduced sufficiently without swelling.

An object of the present invention is to provide a rotary compressor that is easy to manufacture and that can reduce noise caused by a sudden backflow of residual compressed gas having a top clearance volume over a wide range of rotational speed changes while maintaining performance. To do.

[Means for Solving the Problems]

In order to solve the above problems, the present invention provides a rotary compressor in which a top clearance volume is formed between a compression side space in a cylinder and a compressed gas discharge valve, in which the residual compressed gas in the top clearance volume is Immediately before the backflow into the suction side space in the cylinder, a space portion having an appropriate volume for introducing the residual compressed gas is provided in communication with the top clearance volume, and the gas introduced into the space portion is provided at an appropriate position. A passage for returning to the cylinder inner space is provided.

Further, the present invention has a rotor that makes a rotary motion in a cylinder, and partitions a cylinder internal space formed between the cylinder and the rotor into a suction side space and a compression side space by a suction plate, and sucks the suction side space. The compressed gas is compressed and discharged from the compression side space through the compressed gas discharge valve, and a top clearance volume is formed between the compression side space in the cylinder and the compressed gas discharge valve, and the compressed gas remains in the same volume. In a rolling piston type rotary compressor having a structure, immediately before the residual compressed gas in the volume flows back into the suction side space, a space portion communicating with the volume and having an appropriate volume for introducing the residual compressed gas is provided in the rotor. A passage is provided on the end face of the cylinder and returns the gas introduced into the space to the suction side space or the compression side space in the cylinder at an appropriate position. It is characterized in the provision of the end face of the end face of the anchored bearing.

Further, the present invention has a rotor rotating in a cylinder, and a cylinder inner space formed between the cylinder and the rotor is partitioned into a suction side space and a compression side space by a partition plate, and gas sucked into the suction side space Of the structure in which a top clearance volume is formed between the compression side space in the cylinder and the compressed gas discharge valve, and the compressed gas remains in the same volume. In the rolling piston type rotary compressor, immediately before the residual compressed gas in the volume flows back into the suction side space, the volume is communicated with the volume through a passage provided in the partition plate, and a part of the residual compressed gas is communicated. A passage having an appropriate volume for guiding the air to the suction side space in the cylinder is provided in the cylinder or a bearing fixed to the end surface of the cylinder. It is intended to.

[Action]

As described above, a space portion having an appropriate volume is provided, and the residual compressed gas in the top clearance volume is introduced into the space portion immediately before it flows back into the suction side space, thereby reducing the pressure of the gas and reducing the pressure. When the Toff clearance volume is released to the suction side space, the residual gas is made to flow back to the suction side space from the same portion, and the gas introduced into the space is shifted in the cylinder at a proper position with a timing different from the above reverse flow. By causing the gas to flow back into the space, the pressure and amount of the gas flowing back from each are reduced, so the pressure pulsation in the cylinder and its exciting force caused by the backflow are reduced by the amount of the reduction of the pressure and the amount of the backflow gas. Vibration is reduced. On the other hand, the amount of gas that flows back from the top clearance volume is substantially constant even if the rotation speed changes over a wide range, so that no performance deterioration occurs.

In addition, as described above, a space portion having an appropriate volume that communicates with the volume immediately before the residual compressed gas in the top clearance volume flows back to the suction side space is provided on the end surface of the rotor that rotates in the cylinder, and The bearing fixed to the end surface of the cylinder is provided with a passage for returning the gas introduced into the space portion to the suction side space or the compression side space at an appropriate position, and the same passage is provided immediately before the rotor reaches the top clearance volume position by the rotational movement. By communicating the volume with the space and introducing the residual compressed gas into the space, the pressure of the gas is reduced, the rotor rotates the pressure-reduced residual gas, and the top clearance volume becomes the suction side space. When it is opened, the gas is introduced from the same volume into the space on the suction side, and the gas introduced into the space flows back from the volume. Delays the timing and causes the pressure and amount of the gas that flows backward from each of the passages to flow back from the passage to the suction side space or the compression side space at an appropriate position. The excitation force is reduced and the vibration is reduced. On the other hand, the amount of backflow gas from the top clearance volume is substantially constant even if the rotation speed changes widely, and part of the backflow gas is returned to the compression side space, so there is no reduction in volume efficiency and performance is maintained. be able to.

Further, according to the present invention, immediately before the residual compressed gas in the top clearance volume flows back to the suction side space via the passage provided in the partition plate, a part of the gas is appropriately introduced into the suction side space in the cylinder. A passage having a volume is provided, and the residual compressed gas is introduced into the passage to reduce the pressure of the gas in the top clearance volume, and the gas with the reduced pressure is sucked at a timing shifted from the passage and the top clearance volume. By causing the gas to flow back to the side space, the pressure and amount of the gas flowing back from each side are reduced, so that the pressure pulsation in the cylinder and its exciting force caused by the backflow are reduced by that amount, and the vibration is reduced.
Further, since the amount of backflow gas from the top clearance volume is substantially constant regardless of a wide change in the number of revolutions, the performance does not deteriorate.

〔Example〕

 The present invention will be described below based on illustrated embodiments.

FIG. 1 is a cross-sectional view of the rolling piston type rotary compressor in a direction perpendicular to the rotor rotation axis, and FIG. 2 is A- of FIG.
FIG. 2 is a sectional view of A, in which 8 is a suction pipe, 12 is a crankshaft, 20a is a suction side space in a cylinder, 20b is a compression side space in a cylinder, 30 is a cylinder body, 31 is a rotor,
32 is a partition plate, 33 is a notch groove, 34 is a discharge port, 40 is an upper bearing, 41 is a lower bearing, 42 is a discharge valve, 43 is a retainer, 44 is a bolt, and these are the same as the conventional ones described above. It is a composition.

In this example, in addition to the above, a groove having an appropriate depth is further provided in a ring shape on the end surface of the rotor 31 to form a space 50 having an appropriate volume, and the rotor 31 is rotated to reach the inner peripheral surface of the cylinder. Immediately before the contact point of the above reaches the top clearance volume position formed by the cut groove 33 and the discharge port 34, a passage groove 51 for communicating the space portion and the top clearance volume is provided on the end surface of the upper bearing 40, and the rotor 31 Is rotated further and the gas sucked into the suction side space 20a is started to be compressed, and a passage groove 52 for communicating the space 50 with the compression side space 20b in the cylinder is provided at an appropriate position. It is provided diagonally on the end face.

FIG. 1 shows a state immediately before the back flow into the residual compressed gas suction side space 20a in the top clearance volume,
In this state, the rotor 31 approaches the discharge port 34, and the discharge port 34 and the space 50 on the rotor end surface communicate with each other via the passage groove 51 provided in the upper bearing 40. Therefore, the gas in the top clearance volume flows into the space 50 due to the pressure difference, expands, and the pressure drops. Then, when the rotor 31 rotates and the Toff clearance volume is opened to the suction side space 20a, the gas in the volume where the pressure has dropped decreases and flows back to the suction side space 20a.

On the other hand, the gas flowing into the space 50 is temporarily confined in the space 50 because the rotation of the rotor 31 interrupts the communication with the top clearance volume.
When the compressor further rotates and passes the position of the suction pipe 8 to enter the compression process, the space 50 and the compression side space 20b are communicated with each other via the passage groove 52, so that the gas in the space 50 is compressed in the compression side space. Spill into 20b. Here, the gas can be gradually discharged by appropriately selecting the length and the groove area of the passage groove 52.

As described above, since the residual compressed gas in the top clearance volume can be returned to the suction side space 20a and the compression side space 20b at two different timings while reducing the pressure, the back clearance of the gas in the top clearance volume is caused. The pulsation in the cylinder and its exciting force are reduced, and vibration can be reduced.

In addition, the amount of gas that flows back from the top clearance volume is almost constant despite a wide range of revolutions,
Moreover, since the gas introduced into the space portion 50 is made to gradually flow out to the compression side space 20b during the compression process, it is possible to reduce the pulsation in the cylinder without reducing the volume efficiency. As a result, 1-
It is possible to reduce noise over a wide range of 5 KHz.

The passage groove 51 can be omitted if the space portion 50 on the end surface of the rotor 31 can sufficiently communicate with the discharge port 34.

Further, the passage groove 52 is configured to allow the gas in the space portion 50 to flow out to the compression side space 20b during the compression process, but may be made to flow out to the suction side space 20a before the start of compression,
Also, when flowing out to the compression side space 20b, the compression side space 20b
It is necessary to communicate at a position where the internal pressure does not rise too much. Practically, the pressure of the residual gas in the top clearance volume has dropped, and the pressure drop has reduced the approximately the same vibration force during reverse flow, and the pressure of the gas flowing into the space 50 is about the same. The passage groove 52
Does not necessarily have to be a long slanted groove.For example, even if it is composed of a short groove in the radial direction, the position where the pressure pulsates in the cylinder due to backflow from the top clearance volume By determining, the pulsation reducing effect can be obtained by the mutual interference effect of pressure waves having a phase shift.

Further, in the above-described embodiment, the example in which the space portion 50 is provided on the upper surface of the rotor 31 and the passage grooves 51 and 52 are provided on the end surface of the upper bearing 40 has been described, but in the case where the discharge port is provided on the lower bearing 41. Need only be provided with a space and a passage groove on the lower surface and the lower bearing side of the rotor 31, respectively. Furthermore, in the case where the discharge port is provided at two locations, the upper and lower bearings, both end surfaces of the rotor and the upper bearing are provided. -It is sufficient to provide a space and a passage groove in the lower bearing, respectively. In this case, holes are formed in the rotor to connect the two spaces so that the pressure in the space on both end surfaces of the rotor is the same. It is desirable to do so.

Next, the embodiment shown in FIGS. 3 to 5 will be described.

In the figure, 53 is a passage formed by providing a groove or hole at the tip of the partition plate 32 as shown in FIGS. 4 and 5, and the rotor 31 approaches the position of the discharge porter 34 as shown in FIG. However, the top clearance volume when the partition plate 32 is pushed up by the rotor 31 at a position immediately before the gas in the top clearance volume formed by the discharge port 34 and the notch groove 33 flows back into the suction side space 20a. It is designed to communicate with. Further, on the end surface of the upper bearing 40, a passage groove 54 communicating with the passage 53 at the above position, and the volume of the above
A space 55 having a volume of about 1/2 and a passage groove 56 continuous with the suction side space 20a in the cylinder are provided.

According to the above configuration, the residual compressed gas in the top clearance volume partially flows into the space 55 through the passages 53 and 54 immediately before flowing back into the suction side space 20a. Since the volume of the space 55 is about 1/2 of the top clearance volume, this gas amount is about 1/2 of the residual compressed gas amount, and the pressure of this gas is lowered, and the suction side space is passed through the passage groove 56. Spilled to 20a. On the other hand, the gas in the top clearance volume is also reduced in pressure, and when the volume is connected to the suction side space 20a by the rotation of the rotor, the gas flows back into the suction side space 20a.

In this way, the residual gas in the top clearance volume can be reduced in pressure and returned to the suction side space at two different timings, so that the top clearance can be obtained without degrading the performance as in the above-described embodiment. It is possible to reduce the vibration by reducing the pulsation in the cylinder and its exciting force due to the reverse flow of the gas in the volume.

Although the passage groove 54 and the space 55 are provided on the bearing side in the example described above, it goes without saying that they can be provided on the cylinder 30 side.

If the top clearance volume is small,
Since the passage grooves 54 and 56 can secure an appropriate volume, the space 55 can be omitted.

Further, when the opening position of the passage groove 56 to the suction side space 20a is between the suction pipe 8 and the partition plate 32, even if gas is about to flow out from the passage groove 56 to the suction side space 20a, the rotor 31 is immediately removed. Since the gas passes through the position of the passage groove 56, as a result, the residual gas cannot flow out to the suction side space 20a and flows out to the suction side space 20a during the next suction process, resulting in a decrease in volumetric efficiency and performance. Passage groove 56 as it may cause down
The opening position of is preferably on the downstream side of the suction pipe 8.

[Effects of the Invention] As is apparent from the above description, according to the present invention, the pressure of the residual compressed gas in the top clearance volume is reduced, and the timing is shifted to return from two locations to the suction side space and the compression side space. Therefore, it is possible to reduce the pulsation in the cylinder due to the reverse flow of the gas in the top clearance volume and the vibration force due to the pulsation, thereby reducing the vibration and noise.

In addition, even if the rotation speed changes over a wide range, the amount of compressed gas including the top clearance volume gas that flows back into the suction side space and the compression side space does not change, and is substantially constant. There is almost no, and as a result, noise reduction can be achieved while maintaining high performance even in a compressor in which the rotation speed changes over a wide range.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a sectional view of an essential part showing another embodiment. 5 and 5 are perspective views showing the construction of the partition plate, FIG. 6 is a cross-sectional view of a conventional one, and B- in FIG.
B sectional view, FIG. 8 is a sectional view taken along line CC of FIG. 7, FIG. 9 is a pressure waveform diagram in the cylinder, and FIGS. 10 to 13 are configuration diagrams showing other conventional examples. 20 …… Cylinder space, 20a …… Suction side space, 20b …… Compression side space, 30 …… Cylinder body, 31 …… Rotor, 32 ……
Partition plate, 33 ... Notch groove, 34 ... Discharge port, 40 ... Upper bearing, 41 ... Lower bearing, 50 ... Space part, 51 ... Passage groove, 52 ... Passage groove, 53 ... Passage Groove or hole, 54 ... passage groove, 55 ... space portion, 56 ... passage groove.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiyuki Kauchi, Nishibiwajima-cho, Nishi-Kasugai-gun, Aichi Prefecture, Asahi-cho, 3-chome, Air-conditioning factory, Mitsubishi Heavy Industries Ltd. (72) Katsumi Hirooka, Nishibashijima-cho, Nishikasugai-gun, Aichi Prefecture Asahi-cho 3-chome Mitsubishi Heavy Industries, Ltd. Air-conditioning factory (72) Inventor Hiroshi Nimura 60-1 Kutani, Iwatsuka-cho, Nakamura-ku, Nagoya, Aichi Nakabishi Engineering Co., Ltd.

Claims (3)

[Claims] 1. A rotary compressor in which a top clearance volume is formed between a compression side space in a cylinder and a compressed gas discharge valve, wherein residual compressed gas in the top clearance volume is a suction side space in the cylinder. A space having a suitable volume for introducing the residual compressed gas is provided in communication with the top clearance volume immediately before the backflow to the cylinder, and the gas introduced into the space is returned to the space in the cylinder at a suitable position. A rotary compressor having a passage. 2. A cylinder having a rotor rotating in a cylinder, a space inside the cylinder formed between the cylinder and the rotor being divided into a suction side space and a compression side space by a partition plate, and sucked into the suction side space. A structure in which gas is compressed and discharged from a compression side space through a compressed gas discharge valve, and a top clearance volume is formed between the compression side space in the cylinder and the compressed gas discharge valve, and the compressed gas remains in the same volume. In the rolling piston type rotary compressor of, immediately before the residual compressed gas in the volume flows back to the suction side space, a space portion having an appropriate volume communicating with the volume and introducing the residual compressed gas is provided in the rotor. The end of the cylinder is provided with a passage provided on the end face and returning the gas introduced into the space to the suction side space or the compression side space in the cylinder at an appropriate position. Rotary compressor, characterized in that provided on the end face of the anchored bearing. 3. A rotor having a rotary motion in a cylinder, a cylinder inner space formed between the cylinder and the rotor is partitioned by a partition plate into a suction side space and a compression side space, and sucked into the suction side space. A structure in which gas is compressed and discharged from a compression side space through a compressed gas discharge valve, and a top clearance volume is formed between the compression side space in the cylinder and the compressed gas discharge valve, and the compressed gas remains in the same volume. In the rolling piston type rotary compressor, the residual compressed gas in the volume is communicated with the volume through a passage provided in the partition plate immediately before the residual compressed gas flows back to the suction side space. A passage having an appropriate volume for guiding the portion to the suction side space in the cylinder is provided in the cylinder or a bearing fixed to an end surface of the cylinder. That rotary compressor.