JPH02245494A - Noise suppressor for closed-type compressor - Google Patents

Abstract

PURPOSE:To damp different frequencies of generated pressure pulsations so as to secure refrigeration performance by providing plural bottomed cylindrical spaces opened into a cylinder in roughly the same axial direction as that of a delivery port, and making the volume of the spaces smaller as they approach to the delivery port. CONSTITUTION:The opening of a cylinder 5 is sealed by upper and lower bearing sections 11 and 12, and a delivery valve 16 for opening and closing a delivery port 15 is provided in the upper bearing section 11. An eccentric rotary roller 7 is provided in the cylinder 5. Notches 17 and 18 are formed aslant in the end surfaces of the cylinder 5 on the upper and lower bearing section sides, aligning with the axis of the delivery port 15. Bottomed cylindrical spaces 19 and 20 are formed in the notches 17 and 18, and the volume of the space 19 nearer the delivery port 15 is made smaller. Thus, high-frequency pressure pulsation is damped in the space 19, low-frequency pulsation is damped in the clearance 20, and also the volume of residual high-density refrigerant near the delivery port 15 is reduced to prevent the refrigeration performance from being lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a silencer for a hermetic compressor that damps pressure pulsations of a refrigerant compressed within a compression element.

(B) Prior Art A conventional hermetic compressor is constructed as shown in, for example, Japanese Patent Publication No. 11200/1983. Here, a conventional example will be explained with reference to this publication. In FIGS. 5 and 6, 50 is a closed container having a suction pipe 51 and a discharge pipe 52, and an electric element 53 and a compression element 54 driven by the electric element are housed inside this container. .

Reference numeral 55 denotes a cylinder with both ends open, and a roller 57 rotatably fitted to a part of the rotating shaft 56 is installed in the cylinder.
It's decorated. A vane 58 that divides the inside of the cylinder into a low-pressure chamber and a high-pressure chamber is provided in a part of the cylinder 55 so as to be retractable into a guide groove 59, and one end of this vane is always kept in close contact with the side surface of the row 257. A subring 60 is provided within the guide groove 59. In addition, the cylinder 55
A rotating shaft 56 is supported at both ends of the cylinder 55.
An upper bearing portion 61 and a lower bearing portion 62 are respectively provided to seal the end faces of the bearing. Reference numeral 63 designates a discharge port formed in the lower bearing portion 62, which communicates with a high pressure chamber within the cylinder 55, and a discharge valve 64 and a discharge valve holder 65 are provided on the discharge side of the discharge port 63, respectively. ing. Reference numeral 66 denotes a small volume space formed on the side of the lower bearing portion 62 that comes into contact with the cylinder 55, and this small volume space communicates with the discharge port 63 via a pressure introduction path 67. The width of the pressure introduction path 67 is formed to be smaller than the width of the small volume space 66, as shown in FIG.

Reference numeral 68 denotes a discharge muffler body formed in a vessel shape so as to cover the surface of the lower bearing portion 62, and a discharge muffler chamber 69 is formed inside this muffler body.

In a hermetic compressor with this structure, the cylinder 5 of the lower bearing part 62
5 is connected to the discharge port 63 through a pressure introduction path 67 to form a resonant muffler, thereby damping the pressure pulsations of the refrigerant and reducing the noise of the compressor. There is.

(c) Problems to be Solved by the Invention However, in the resonance type muffler, the small volume space 66 and the pressure introduction passage 67 are formed in the thin lower bearing part 62 in separate steps, and the small volume space 66 and the pressure introduction path 67 are formed in the vicinity of the discharge port 63. Since one is provided,
It is difficult to process the product so that the strength does not decrease, and it is only possible to attenuate one frequency among the pressure pulsation frequencies of the refrigerant, making it insufficient to attenuate pressure pulsations that affect the outside as noise. There was a problem.

This invention solves the above problems by simplifying the processing of spaces, attenuating multiple frequencies in pressure pulsating waves that affect the outside as noise, and reducing the number of frequencies remaining in multiple spaces. The purpose of the present invention is to provide a silencer for a hermetic compressor, the purpose of which is to reduce the amount of refrigerant used to suppress a decrease in refrigerating capacity.

(d) Means for Solving the Problems This invention includes a compression element housed in a closed container, a cylinder, a roller rotating inside the cylinder by an eccentric part of a rotating shaft, and a low pressure chamber in contact with the roller inside the cylinder. It consists of a vane that partitions into a high-pressure chamber and a bearing that closes the opening of the cylinder, and the bearing is provided with a discharge port and a discharge valve that opens and closes the discharge port, and a valve that opens into the cylinder. A cylindrical space with a bottom is provided in this cylinder, and a plurality of cylindrical spaces with a bottom are provided in the axial direction at approximately the same position as the discharge port, and the volumes of the plurality of spaces are changed, and a side close to the discharge port is provided. The following explanation will be based on the assumption that the volume of the space is smaller than the volume of the space away from the discharge port.

Reference numeral 1 denotes a closed container, in which an electric element 3 having a rotation shaft 2 on the upper side and a rotary compression element 4 driven by the rotation shaft 2 of this electric element on the lower side are housed. The element 4 includes a cylinder 5, an eccentric portion 6 of the rotating shaft 2,
A vane 10 that contacts the rollers and divides the inside of the cylinder 5 into a low-pressure chamber 8 and a high-pressure chamber 9, and an upper bearing that closes the opening of the cylinder 5. 11, a lower bearing part 12, and a discharge muffler body 13 attached to cover the surface of the upper bearing part. The upper bearing portion 11 is provided with a discharge port 15 that communicates the high pressure chamber 9 of the cylinder 5 with a discharge muffler chamber 14 formed inside the discharge muffler body 13 . A discharge valve 16 for opening and closing the discharge port 15 is attached to the upper bearing portion 11 on the outlet side of the discharge port. Reference numerals 17 and 18 denote notches provided in the end faces of the cylinder 5 on the upper bearing part 11 side and the lower bearing part 12 side, and these notches are formed diagonally and are provided in alignment with the axial direction at the same position as the discharge port 15. It is being Reference numerals 19 and 20 denote bottomed cylindrical spaces provided in the notches 17 and 18, and these spaces convert the volume on the upper bearing part 11 side near the discharge port 15 to the lower bearing part 12 side away from the discharge port. It is small compared to its volume. That is, the space 19 on the upper bearing part 11 side is made short in depth to attenuate high-frequency pressure pulsations, and the space 20 on the lower bearing part 12 side is made long in depth to attenuate low-frequency pressure pulsations. ing.

21 is a suction passage formed in the cylinder 5, and this suction passage communicates with the low pressure chamber 8. 22 is a discharge pipe, and this discharge pipe is attached to the earthen wall of the closed container 1.

In the silencer for a hermetic compressor configured in this manner, the refrigerant flowing into the cylinder S from the suction passage 21 is compressed by the cooperation of the roller 7 and the vane 10, and the discharge valve 16 is opened from the discharge port 15. and is discharged into the discharge muffler chamber 14 of the discharge muffler body 13. The refrigerant in the discharge muffler body is then discharged from the discharge pipe 22 to an external cooling circuit (not shown) through the closed container 1.

Space 19.20 provided in cutout 17.18 of cylinder 5
By opening on the high pressure chamber 9 side in this cylinder, pressure pulsation components generated due to rapid expansion of compressed refrigerant flowing from the high pressure chamber 9 toward the discharge port 15 during the discharge stroke and the closing of the discharge valve 16 can be prevented. Attenuates two frequencies that vibrate the compressor, including the pressure pulsation component generated by the sudden expansion of the compressed refrigerant remaining near the discharge port 15 at the end of the discharge stroke when it is released to the low pressure chamber 8. , the level of pressure waves transmitted into the discharge muffler chamber 14 and cylinder 5 is reduced. Furthermore, the spaces 19 and 20 are designed to suppress noise in the entire frequency band by attenuating frequency components transmitting noise to the outside using a resonant muffler mechanism.

In addition, the two spaces 19 and 20 are designed to reduce the residual capacity of refrigerant with high refrigerant density by making the volume of the space 19 near the discharge port 15 smaller than the volume of the space 20 away from the discharge port. This ensures that the refrigeration capacity does not decrease. That is, when the refrigerant is flowing from the high pressure chamber 9 in the cylinder 5 toward the discharge port 15, the refrigerant density in the high pressure chamber 9 is high on the upper bearing portion 11 side near the discharge port 15, and the refrigerant from this discharge port The refrigerant density on the remote lower bearing portion 12 side is lower, making it possible to reduce the substantial amount of refrigerant remaining in the large volume space 20.

This invention provides two different bottomed cylindrical spaces 19 and 20 in the axial direction at the same position as the discharge port 15, and reduces the volume of the space 19 near the discharge port 15, thereby compressing the refrigerant. Attenuates the two different frequency components of the pressure pulsation components generated by the cooling system to suppress the noise generated outside, and also reduces the amount of refrigerant remaining in the two spaces 19 and 20 to prevent the refrigerating capacity from decreasing. This is what I did.

(G) Effects of the Invention As described above, according to the present invention, a plurality of bottomed cylindrical spaces opening in the cylinder are provided in the axial direction at approximately the same position as the discharge port, and the volumes of these spaces are In addition to reducing the volume of the space near the discharge port, the different frequencies of the pressure pulsation components generated by the compression of the refrigerant are attenuated in multiple spaces, reducing the noise caused by pressure pulsations. At the same time, the volume of the space in which the high-density refrigerant remains is reduced to prevent the refrigerating capacity from decreasing due to these spaces.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a rotary compressor showing an embodiment of the present invention, FIG. 2 is a cross-sectional view of the rotary compressor, FIG. The drawings are a sectional view taken along the line A-A in FIG. 3, FIG. 5 is a sectional view of a rotary compressor showing a conventional example, and FIG. 6 is a perspective view of the main parts of the muffler mechanism. DESCRIPTION OF SYMBOLS 1... Airtight container, 2... Rotating shaft, 3... Electric element, 4... Rotating compression element, 5... Cylinder, 6... Eccentric part, 7... Roller, 8...・・・
Low pressure chamber, 9... High pressure chamber, 10... Vane, 1
1... Upper bearing part, 12... Lower bearing part, 15...
・Discharge port, 16...Discharge valve, 17.18...
・Notch, 19.20...Space.

Claims (1)

[Claims] 1. An electric element having a rotating shaft and a compression element driven by the rotating shaft of the electric element are housed in a closed container,
This compression element includes a cylinder, an eccentric part of a rotating shaft, a roller that rotates inside the cylinder by this eccentric part, a vane that comes into contact with this roller and divides the inside of the cylinder into a low pressure chamber and a high pressure chamber, and an opening in the cylinder. It consists of a bearing part that seals the
In the hermetic compressor, the bearing portion is provided with a discharge port and a discharge valve for opening and closing the discharge port, and the cylinder is provided with a bottomed cylindrical space opening into the cylinder. A plurality of cylindrical spaces are provided in the axial direction at approximately the same position as the discharge port, and the volumes of the plurality of spaces are changed, and the volume of the space near the discharge port is changed to the volume of the space far from the discharge port. A silencer for a hermetic compressor, which is characterized by being smaller than the previous model.