JPH0697039B2 - Rotary compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a rotary compressor designed to reduce noise due to pressure pulsation generated in a cylinder.

(Prior Art) Generally, in a rotary compressor used in a refrigeration cycle, a roller 2 is incorporated in a cylinder chamber 1a of a cylinder 1 together with a crankshaft 3 as shown in FIGS. A main bearing 4 and a sub-bearing 5 are provided in the portion to close the opening of the cylinder 1. A blade 8 that partitions the cylinder chamber 1a into a suction chamber 6 and a compression chamber 7 is provided in the cylinder 1 so as to be able to move forward and backward, and a suction port 9 is provided adjacent to the blade 8 in the cylinder wall. Further, a discharge port 10 is provided in the main bearing 4 adjacent to the blade 8 together with the discharge valve 11, and a cylinder discharge portion 12 (the discharge port of the cylinder 1 together with the previous discharge port 10 is provided on the cylinder wall portion connected to the discharge port 10. The structure which provided the thing which comprises a part) is used. Reference numeral 13 denotes a valve cover (also serving as a discharge muffler) provided so as to cover the side surface of the main bearing 4, and 14 denotes a valve retainer.

Such a rotary compressor rotates the rotating shaft 3 by an electric motor section (driving source) to thereby generate a suction port 9
After the gas (refrigerant) sucked from the cylinder 1 is compressed in the cylinder 1, the gas is discharged from the cylinder discharge part 12, the discharge port 10, and the discharge valve 11.

By the way, such a rotary compressor has a problem that high frequency noise is emitted during operation. Therefore, conventionally, there has been proposed a technique for reducing such high frequency noise and pressure pulsation (high frequency) in the compression chamber, which causes the high frequency noise, and noise has been reduced.

Specifically, JP-A-59-141787 and JP-A-59-1583.
As shown in Japanese Patent Publication No. 96, on the inner peripheral wall surface of the cylinder 1,
A relief groove (not shown) is provided in a portion of the cylinder chamber 1a on the side opposite to the crank rotation direction from the discharge port 10, and the high pressure side and the low pressure side are communicated through the relief groove to reduce pressure pulsation.

As shown in Japanese Utility Model Laid-Open No. 60-32585, the cylinder 1
A space (not shown) is provided between the main bearing 4 and the main bearing 4 (or the sub bearing 5), and the space is opened to an intermediate pressure portion in the cylinder 1 to reduce pressure pulsation.

As shown in Japanese Utility Model Laid-Open No. 56-2080, Japanese Patent Laid-Open No. 59-3198 and Japanese Patent Laid-Open No. 59-58179, the discharge port 10
There is a flange or the like in the vicinity of which is provided with a cavity or a space (both not shown) to reduce pressure pulsation.

However, according to the technique described at the beginning, the pressure pulsation can be reduced only when the crank rotation angle of the roller 2 coincides with the relief groove. Therefore, the pressure pulsation generated when the discharge valve 10 is closed cannot be reduced. I have

Also, the technique described next can reduce the pressure pulsation until the crank rotation angle passes through the space, but has the drawback that the pressure pulsation at the time of valve closing after the passage cannot be reduced.

On the other hand, the last-mentioned technique can reduce pressure pulsation when the valve is closed, but it is difficult to process because it forms a cavity (or space) in the flange that has a thin wall thickness of 2-3 mm. I have

(Problems to be Solved by the Invention) In other words, the conventional technology has been a bottleneck in silencing noise either in terms of reduction performance or processing of space.

The present invention has been made in view of such a problem, and an object thereof is to easily process a space and reduce pressure pulsation that occurs between the time when the valve is opened and the time when the valve is closed. It is to provide a rotary compressor that can.

[Structure of the Invention] (Means and Actions for Solving Problems) This invention is directed to a space 15 in either or both of the cylinder 1 and the bearing 5 that closes the opening of the cylinder 1.
And the discharge port 11 of the cylinder 1 and the blade 8
In between, and at the end of the side surface portion of the cylinder opposite to the side surface portion having the discharge port portion, the inlet port communicating with the space 15 is opened and located on the line in the thickness direction passing through the discharge port portion. By forming 16 to connect the space 15 and the compression chamber 7, the pressure pulsation is reduced both when the valve is open and when the valve is closed, and at the same time, it is easy to process the space 15.

(Embodiment) Hereinafter, the present invention will be described based on a first embodiment shown in FIGS. 1 and 3. FIG. 1 shows the discharge system of the rotary compressor in an enlarged manner, and this discharge system is provided with a sound deadening structure which is a main part of the present invention. Here, the parts other than the sound deadening structure are the same as the structure of the general rotary compressor described in the above-mentioned "Prior Art", so that only the essential parts will be described here.

That is, 15 is a bottomed cylindrical space provided inside the cylinder 1 along the thickness direction of the cylinder 1. Specifically, as shown in FIG. 2, the space 15 is provided on the side surface opposite to the side surface having the cylinder discharge portion 12 on the line in the thickness direction passing through the cylinder discharge portion 12, and the opening is provided with the auxiliary bearing 5. It faces the side. On the other hand, 16 is an inlet having a cross-sectional area substantially the same as the cross-sectional area of the above space 15. The inlet 16 is provided between a blade groove 8a (a groove for guiding the blade 8) formed in the cylinder 1 and a cylinder discharge part 12 (corresponding to a discharge port). Specifically, as shown in FIG. 2, the introduction port 16 is provided at the end of the side face opposite to the side face where the cylinder discharge part 12 is located and on the line in the thickness direction passing through the cylinder discharge part 12. It opens to the compression chamber of the cylinder chamber 1a. The introduction port 16 is formed in a tubular shape along the radial direction of the cylinder 1 and communicates with the space 15. Further, the introduction port 16 and the space 15 constitute a structure that forms an L-shaped tubular silencing space.

However, such a rotary compressor rotates eccentrically with the roller 2 as the crankshaft 3 rotates,
The gas (refrigerant) sucked from the suction port 9 is compressed in the cylinder 1. Then, after that, the compressed gas is discharged from the cylinder discharge part 12 and the discharge port 10 through the discharge valve 11. Incidentally, such a compression stroke is performed by the displacement H of the discharge valve 10 shown in FIG.

During such a compression stroke, pressure pulsations related to the discharge valve 11 as shown in FIG. 3 are generated in the compression chamber 7 of the cylinder 1 and become noise. That is, the pressure pulsation occurs from immediately after the discharge valve 11 is opened to after the discharge valve 11 is closed. Immediately after the pressure pulsation, a relatively low frequency pressure pulsation (769 Hz) A
However, high-frequency pressure pulsations (4670 Hz) B are generated at the time of closing. The low-frequency pressure pulsation A is determined by the cavity size of the compression chamber 7 and the cavity formed by the valve cover 13 and the main bearing 4, and the high-frequency pressure pulsation B is determined by the cavity size of the compression chamber 7. is there.

However, the introduction port 16 communicating with the space 15 is provided between the blade 8 and the cylinder discharge unit 12. This is the introduction
It can be seen that 16 opens in the compression chamber 7 of the cylinder 1 not only when the discharge valve 11 is open, but also when the discharge valve 11 is closed.

Therefore, the pressure pulsation that occurs between the time when the valve is opened and the time when the valve is closed can be reduced by using the space 15 as in the conventional case. Specifically, when the pressure pulsation B of a specific high frequency that becomes high frequency noise is reduced, for example, with the inlet 16,
The sum of the length of the space 15 in the longitudinal direction may be about 1/4 of the wavelength of the pressure pulsation frequency. In addition, if the cross-sectional area of the inlet 16 is made smaller than the cross-sectional area of the space 15 so that the resonance frequency of the silencer substantially matches the pressure pulsation frequency generated in the compression chamber 7, for example, B, the low frequency is reduced. It can be understood that the pressure pulsation can be reduced over a wide frequency band including the pressure pulsation. Moreover, since the space 15 is provided in a portion other than the flange portion of the discharge valve 11 which is difficult to process, it has an advantage that it can be easily processed.

The present invention is not limited to the first embodiment described above, but the fourth embodiment.
Second embodiment shown in FIGS. 5 and 5, FIGS. 6 and 7
Third embodiment shown in the figure, fourth embodiment shown in FIGS. 8 and 9
The same applies to the case of the embodiment.

That is, in the second embodiment, the sub-bearing 5 is provided with the inlet 16 which also serves as the space 15 and is opened in the compression chamber 7.

In the third embodiment, the sub bearing 5 is provided with a recessed space 15 in which the introduction port 16 is integrated.

In the fourth embodiment, the cylinder 1 is provided with a cylindrical space 15 in which the introduction port 16 is integrated, at an angle. In particular, this has the advantage that it can be easily machined with a drill or the like.

In addition, it is needless to say that the inlet 16 is open between the blade 15 and the cylinder outlet 11 in all the examples. Further, in any of the examples, the space length is set to λ / 4 (where λ is the wavelength), the inlet 16 and the space 15 are used to reduce the pressure pulsation.
It is used to make the resonance frequency composed of and substantially match the pressure pulsation frequency.

[Effects of the Invention] As described above, according to the present invention, the space can be easily processed, and at the same time when the valve is opened or closed, the introduction port communicating with the compression chamber allows the valve to be opened to closed. It is possible to reduce the pressure pulsation that occurs during the operation in space.

As a result, the noise can be reduced, and at the same time, the silencer can be easily configured.

[Brief description of drawings]

FIG. 1 is a sectional view showing the periphery of a discharge valve, which is a main part of a first embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. 3 is a displacement of the discharge valve. And a pressure pulsation in the cylinder, FIG. 4 is a sectional view showing a discharge valve and its surroundings, which is an essential part of the second embodiment of the present invention, and FIG.
FIG. 6 is a sectional view taken along the line BB, FIG. 6 is a sectional view showing the vicinity of the discharge valve, which is the main part of the third embodiment of the present invention, and FIG. 7 is a sectional view taken along the line CC of FIG. FIG. 8 and FIG. 8 are sectional views showing the vicinity of the discharge valve, which is an essential part of the fourth embodiment of the present invention.
8 is a sectional view taken along line D-D of FIG. 8, FIG. 10 is a sectional view showing an ordinary rotary compressor, FIG. 11 is a plane sectional view taken along line E-E of FIG. 10, and FIG. It is sectional drawing which expands and shows the discharge valve circumference of FIG. 1 ... Cylinder, 1a ... Cylinder chamber, 2 ... Roller, 4,
5 …… Main bearing, auxiliary bearing (bearing), 8 …… Blade, 8a…
… Blade groove, 10,12 …… Discharge port, cylinder discharge part (discharge port), 15 …… Space, 16 …… Inlet port.

Claims (4)

[Claims] 1. A rotary compressor having a rotor provided eccentrically and rotatably in a cylinder chamber of the cylinder and a blade partitioning the cylinder chamber into a suction chamber and a compression chamber, the cylinder or the opening of the cylinder being closed. A space is provided in either one or both of the bearings, and an inlet for communicating the space with the compression chamber is provided between the discharge port of the cylinder and the blade, and a side surface part having the discharge port of the cylinder. A rotary compressor characterized in that it is located on a line in the thickness direction passing through the discharge port section at the end of the side surface section on the opposite side to and is opened in the cylinder. 2. The introduction port and the space are formed in a cylindrical shape having substantially the same cross-sectional area.
The rotary compressor described in the item. 3. The sum of the lengths of the inlet and the space in the longitudinal direction is about 1/4 of the wavelength of the pressure pulsation frequency generated in the compression chamber of the cylinder.
The rotary compressor according to claim 2, characterized in that 4. The inlet and the space are characterized in that the sectional area of the inlet is set to be smaller than the sectional area of the space, and the resonance frequency is made substantially equal to the pressure pulsation frequency generated in the compression chamber of the cylinder. The rotary compressor according to claim 1.