JPS62253991A - Rotary compressor - Google Patents

Abstract

PURPOSE:To reduce the pulsation of pressure by providing a space on either or both of a cylinder and a bearing and forming an introducing port which connects said space to a compression chamber in said cylinder on a part between the discharge port part of said cylinder and a blade part. CONSTITUTION:A space 15 is provided on either or both of a cylinder 1 or a bearing 5 which closes the opening of the cylinder 1. And, an introducing port 16 which is connected to the space 15 is provided in between a discharge port part 10 for the cylinder 1 and a blade 8 to connect the space 15 to a compression chamber. Thereby, the pulsation of pressure can be reduced when a valve is both opened and closed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention (Industrial Application Field) This invention relates to a rotary compressor that reduces noise due to pressure pulsations generated within a cylinder.

(Prior Art) In a rotary compressor generally used in a refrigeration cycle, a roller 2 is disposed within a cylinder 1 of a cylinder 1 and a crankshaft 3, as shown in FIGS. 10 to 12.
The main bearing 4 is installed on the side of the cylinder 1. Secondary bearing 5
is provided to close the opening of the cylinder 1. A blade 8 that partitions the cylinder chamber 1a into a suction hole 6 and a compression hole 7 is provided in the cylinder 1 in a movable manner, and a suction port 9 is provided in the cylinder wall adjacent to the blade 8. Further, a discharge port 10 is connected to the main bearing 4 adjacent to the blade 8, and a discharge valve 1 is connected to the discharge port 10.
1, a structure is used in which a cylinder discharge portion 12 (which together with the discharge port 10 constitutes the discharge port portion of the cylinder 1) is provided in the cylinder wall portion continuous to the discharge port 10. Note that 13 indicates a valve cover (also serves as a discharge muffler) provided to cover the side surface of the main bearing 4, and 14 indicates a valve holder.

Such a rotary compressor uses a suction port 9 by rotating the rotating shaft 3 with an electric motor (drive source).
After compressing the gas (refrigerant) sucked in from the cylinder 1, the gas (refrigerant) sucked in from the cylinder discharge part 12. Discharge port 10. It is discharged from the discharge valve 11.

However, such rotary compressors have the problem of emitting high-frequency noise during operation. Therefore, techniques have been proposed to reduce the pressure pulsations (high frequencies) in the compression chamber that cause such high frequency noise, and attempts have been made to reduce the noise.

Specifically, JP-A-59-141787.

As shown in Japanese Unexamined Patent Publication No. 59-158396, a discharge port 1 of a cylinder chamber 1a is located on the inner circumferential wall surface of a cylinder 1.
A relief groove (not shown) is provided in the part opposite to the crank rotation direction from 0, and the pressure pulsation is reduced by communicating the overwhelm and the low pressure side through this relief groove.

As shown in Japanese Utility Model Application Publication No. 60-32585, there is an air gap between the cylinder 1 and the main bearing 4 (or sub-bearing 5).
n (not shown) is provided, and this space is opened to an intermediate pressure section within the cylinder 1 to reduce pressure m movement.

As shown in Japanese Utility Model Application Publication No. 56-2080, Japanese Patent Application Publication No. 59-3198, and Japanese Patent Application Publication No. 59-58179, there is a cavity or cavity II! in the flange portion near the discharge port 10. (none of which are shown) is provided to reduce pressure pulsations.

However, according to the technique mentioned at the beginning, the pressure pulsations can only be reduced when the crank rotation angle of the roller 2 matches the relief groove, so the disadvantage is that the pressure pulsations that occur when the discharge valve 10 closes cannot be reduced. have.

Furthermore, although the technique described next can reduce pressure pulsations until the crank rotation angle passes through the space, it has the drawback that it cannot reduce pressure pulsations when the valve is closed after the crank rotation angle passes through the space.

On the other hand, the last technique mentioned is that the pressure when the valve is closed is 1# [
Although it is possible to reduce the 1ll, it has the disadvantage that it is difficult to process because a cavity (or space) is formed in the flange portion, which has a thin wall thickness of 2 to 3 times.

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

This invention was made with attention to these problems, and its purpose is to not only make it easy to process the space, but also to reduce pressure pulsations that occur between the time the valve opens and the time the valve closes. Our goal is to provide rotary compressors that can.

[Structure 1 of the invention (Means and effects for solving the problems)] This invention provides a cylinder 1 or a bearing 5 that closes an opening of this cylinder 1.
Either one or both of the spaces 15 are provided, and an inlet 16 communicating with the space 15 is formed between the discharge port portion 11 of the cylinder 1 and the blade 8, so that the space 15 and the compression! By communicating with 7, pressure pulsations are reduced both when the valve is opened and when the valve is closed, and the space 15 is made easier to process.

(Example) The present invention will be described below based on a first example shown in FIGS. 1 and 3. FIG. 1 shows an enlarged view of the discharge system of a rotary compressor, and this discharge system is provided with a noise reduction structure, which is the essential part of the present invention. Here, the parts other than the silencing structure are the same as the structure of the general rotary compressor described in the "Prior Art" section above, so only the main parts will be explained 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.
is provided on the side opposite to the side where the cylinder is located, on a line in the thickness direction passing through the cylinder discharge part 12, and the opening is connected to the sub bearing 5.
It is facing the side of On the other hand, reference numeral 16 denotes an inlet having approximately the same cross-sectional area as the previous space 15. This introduction port 1
6 is the blade 'a8a (groove for guiding the blade 8) formed in the cylinder 1 and the cylinder discharge 8! ! 12 (corresponding to a discharge port).

Specifically, as shown in FIG. 2, the inlet 16 is located at the end of the I1 plane opposite to the m plane where the cylinder discharge part 12 is located, on a line in the thickness direction passing through the cylinder discharge part 12. , opens into the compression chamber of the cylinder chamber 1a.

Further, the introduction port 16 is formed in a cylindrical shape along the radial direction of the cylinder 1, and has the above-described structure.

In such a rotary compressor, the roller 2 rotates eccentrically as the crankshaft 3 rotates, so that the gas (refrigerant) sucked from the suction port 9 is transferred to the cylinder 1.
Compress within. After that, the cylinder discharge part 12. Compressed gas is discharged from the discharge port 10.

Note that such a compression stroke is performed at a 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 occur within the cylinder 1 pressures 11 to 7.
It becomes noise. That is, pressure pulsations occur from after the discharge valve 11 opens until after the discharge valve 11 is closed, and a relatively low-frequency pressure pulsation (7
61) A is high frequency pressure 11#1a (4
670 cities) B occurs respectively. Note that the low frequency pressure pulsations A are determined by the cavity dimensions of the pressure chamber 7 and the dimensions of the cavity formed by the valve cover 13 and the main bearing 4, and the high frequency pressure pulsations B are determined by the cavity dimensions of the compression chamber 7. It is.

It can be seen that the introduction 016 opens into the compression chamber 7 of the cylinder 1 not only when the discharge valve 11 is opened but also when the discharge valve 11 is closed.

Therefore, the pressure pulse e 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 reducing a specific high-frequency pressure pulsation B that becomes high-frequency noise, for example, the inlet 16
The sum of the length of the space 15 and the length of the space 15 in the longitudinal direction may be approximately 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 muffler substantially matches the pressure pulsation frequency generated within the compression chamber 7, for example B, low frequencies can be reduced. This means that the pressure VAa can be reduced over a wide range of frequency bands. Furthermore, 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 also has the advantage of being easy to process.

Note that this invention is not limited to the first embodiment described above, but also includes the fourth embodiment.
and the second fruit 7 shown in FIG. 5]! ! The same applies to the third embodiment shown in FIGS. 6 and 7, and the fourth practical example shown in FIGS. 8 and 9.

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

In the third embodiment, a concave space 15 with an integrated introduction port 16 is provided in the auxiliary bearing 5.

In the fourth embodiment, a cylindrical space 15 with an integrated introduction 016 is obliquely provided in the cylinder 1. especially,
This has the advantage that it can be easily machined using a drill or other machine tool.

Incidentally, in all the embodiments, the introduction port 16 is of course open between the blade 15 and the cylinder discharge port 11. In addition, in both embodiments, to reduce pressure pulsations, the space length is set to λ/4 (where λ is the wavelength), and the inlet 1
6 and space 15 to substantially match the pressure pulsation frequency.

[Effects of the Invention] As explained above, according to the present invention, the space can be easily machined, and the inlet that communicates with the compression mold whenever the valve is opened or closed allows the valve to be closed from the time the valve is opened to the time the valve is closed. The pressure pulsations that occur during this time can be reduced in space.

As a result, it is possible to reduce noise, and at the same time, it is possible to easily configure the muffler.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing the main parts of the first embodiment of the invention, such as the discharge valve, Fig. 2 is a cross-sectional view taken along line A-1m in Fig. 1, and Fig. 3 shows the displacement of the discharge valve. FIG. 4 is a sectional view showing the main part of the second embodiment of the present invention, around the discharge valve, and FIG. 5 is the fourth embodiment.
6 is a sectional view showing the main parts of the third embodiment of the present invention, such as the discharge valve, and FIG. 7 is a sectional view taken along line C-C in FIG. 6. FIG. 8 is a sectional view showing the main part of the fourth embodiment of the present invention, around the discharge valve, and FIG.
The figure is a sectional view taken along line C-C in Figure 8, Figure 10 is a sectional view showing a normal rotary compressor, Figure 11 is a plan sectional view taken along line E-E in Figure 10, and Figure 12 is a sectional view taken along line C-C in Figure 10. 1st
FIG. 2 is an enlarged cross-sectional view showing the area around the discharge valve shown in the figure. 1... Cylinder, 1a... To cylinder, 2... Roller, 4, 5... Main bearing, Ill bearing (bearing), 8
...Blade, 8a...Blade groove, 10.12.
...Discharge port, cylinder discharge part (discharge port), 15
...Space, 16...Inlet. Applicant's representative Patent attorney Takehiko Suzue No. 4! ! I 215Figure 116EiiH217Figure 8 rl! l IIE9 rlI
l 10th 1! f Figure 11

Claims (4)

[Claims] (1) In a rotary compressor, in which a roller is provided eccentrically rotatably in a cylinder chamber of a cylinder, and a blade is provided to partition the cylinder chamber into a suction chamber and a compression chamber, the cylinder or a bearing that closes the opening of this cylinder is provided. A rotary compressor characterized in that a space is provided in one or both of the above, and an inlet that communicates this space with a compression chamber is opened in the cylinder between the discharge port portion of the cylinder and the blade. (2) The rotary compressor according to claim 1, wherein the inlet and the space are formed in a cylindrical shape with substantially the same cross-sectional area. (3) The sum of the longitudinal lengths of the inlet and the space is approximately 1/4 of the wavelength of the pressure pulsation frequency occurring in the compression chamber of the cylinder. Rotary compressor as described. (4) The inlet and the space are formed by setting the cross-sectional area of the inlet to be smaller than the cross-sectional area of the space so that the resonance frequency substantially matches the pressure pulsation frequency occurring within the compression chamber of the cylinder. A rotary compressor according to scope 1.