JPH07310658A - Hermetic motor-operated compressor - Google Patents

Abstract

PURPOSE:To provide a compressor which is constituted to reduce the generation of noise and prevent the occurrence of defectiveness owing to breakage of a discharge line. CONSTITUTION:A suction muffler 30 wherein a cylinder head 28 is coupled to a gas passage 29 is provided and a suction hole 32 is arranged approximately on the central line 31 thereof. Left and right cavity volumes 33 and 34 are provided with the central line 31 therebetween and the left and the right cavity volumes are arranged in positions spaced away from each other and a communication passage 35 for the left and right cavity volumes 33 and 34 and the suction hole 32 are intercommunicated approximately on the central line.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor (hereinafter referred to as a compressor) used in an electric refrigerator or the like.

[0002]

2. Description of the Related Art A compressor used in a cooling system of a recent electric refrigerator or the like has low noise caused by operation and
Good energy efficiency (EER) is required. US Pat. No. 5,228,843 has been proposed as a solution to this problem.

An example of the above-mentioned compressor will be described below with reference to the drawings. FIG. 9 shows a side sectional view of a conventional compressor, in which a compression element 2 and an electric element 3 which are elastically mounted are housed in a hermetically sealed case 1.

A hermetic terminal 4 is fixed to the side surface of the closed case 1 and electrically connected to the electric element 3.

A cylinder head 5 is arranged at the end of the compression element 2, and the cylinder head 5 is connected to a suction muffler 6. The suction tube 1a is arranged near the inlet hole 7 of the suction muffler.

FIG. 10 shows the cylinder head and the suction muffler taken along the line AA of FIG.

FIG. 11 is a sectional view taken along the line BB of FIG. 10, FIG.
2 shows the CC arrow view of FIG. 10 to 12, the suction muffler 6 connected to the cylinder head 5 has an inlet hole 7, a gas passage 8, a muffler chamber 9,
10, a small hole 11, 12, and a suction port 13 to the cylinder are provided.

In the above structure, the return gas returned from the cooling system (not shown) to the compressor enters the inlet hole 7 which is close to the suction tube 1a, and the gas passage 8 and the muffler chambers 9 and 10 are provided. Through the small holes 11, 12 as shown by the arrow in FIG. 12, and is sucked into the cylinder of the compression element 2 from the suction port 13. Therefore, the return gas enters the cylinder without being heated, so that the energy efficiency (EER) is relatively good.

[0009]

However, in the above structure, the muffler chamber 9 of the suction muffler 6,
Reference numeral 10 is a resonance type muffler, which has a problem that driving noise is large because it is effective only for a specific narrow range of frequencies.

In view of the above-mentioned problems, the present invention provides a compressor that produces low operating noise.

[0011]

In order to solve the above problems, a compressor of the present invention comprises a suction muffler in which a cylinder head and a gas passage are connected to each other, and the muffler is substantially left and right through a communication passage. A cavity volume is formed by being separated into objects, and a suction hole communicating with the gas passage is formed in a communication passage of substantially center lines of both cavity volumes.

Further, the volume of the cavity on the left side and the volume of the cavity on the right side are substantially equal to each other. Further, the cavity volume on the left side and the cavity volume on the right side are arranged apart from each other, and a hermetic terminal fixed to the hermetic case is disposed between the cavity volumes on the left and right.

Further, the gas inlet of the suction muffler is installed in one of the left and right cavity volumes, and the gas inlet is made of a plastic made of the same material as the suction muffler and formed into a tube shape, and the end face of the gas inlet resonates. It is installed near the node of the resonance mode of frequency, and the seam of the suction muffler is hermetically joined by high frequency welding.

A suction tube for guiding the return gas is arranged at a position opposite to the side wall of the cavity volume, and a gas inlet portion is arranged on a part of the side wall surface of the cavity volume near the opening of the suction tube. .

Further, the gas inlet portion of the suction muffler constitutes a tubular gas inlet tube made of an elastic material such as rubber, and is fixed to the side wall or upper surface wall of the suction muffler, and the end face of the gas inlet tube is resonated at a resonance frequency. It is placed near the mode section.

[0016]

According to the present invention, with the above structure, the left and right cavity volumes serve as cushions for gas blown back from the cylinder, and the left and right cavity volumes communicate with the suction holes and the end faces of the gas inlet section. Is a node of the resonance frequency wavelength, so that the noise is significantly reduced.

Since the hermetic terminals can be housed between the left and right cavity volumes, the entire compressor can be designed compact, that is, downsized.

Since the gas inlet can be made of the same material as that of the suction muffler and formed into a tube shape, the mass productivity is excellent.

The return gas collides with the side wall of the cavity in which heat is hard to be transmitted, and the liquid refrigerant and the refrigerator are separated. Then, the frozen gas is sucked through the gas inlet of the suction muffler.

Since the gas inlet to the suction muffler is molded from an elastic material such as rubber which is separate from the suction muffler, the suction muffler molding die is simple and inexpensive, and the compressor can be provided at a low price.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A compressor according to an embodiment of the present invention will be described below with reference to the drawings. The same parts as those of the conventional example will be described using the same reference numerals, and the same parts of the configuration and the operation will be omitted.

1 to 5, a hermetic terminal 21 is fixed to the closed case 20. The hermetically sealed case 20 includes a block 24 having a cylinder 23 having an opening end 22 elastically attached thereto, a piston 25 in the cylinder 23, and a motor 26 for reciprocating the piston 25.

It has a valve plate 27 fixed to the cylinder block 24 and a cylinder head 28 for covering the valve plate 27.

A suction muffler 30 is connected to the cylinder head 28 and the gas passage 29. The muffler has a cavity volume 33, which is substantially symmetrical to the left and right through a communication passage 35.
34, and a suction hole 32 that communicates with the gas passage 29 is formed in a communication passage 35 that is substantially at the center line of the two cavity volumes.

Thus, the cavity volume 33 on the left side and the cavity volume 34 on the right side have substantially the same size. In FIG. 5, the right side looks large, but the cavity volume 34 excluding the gas inlet portion 36 shaped like an L-shaped tube is equal to the left cavity volume 33.

In the above structure, the return gas returned from the cooling system (not shown) to the compressor is the gas inlet portion 36 which is close to the suction tube 20a.
Inhaled from. On the other hand, with respect to the blowback gas from the cylinder (the gas compressed by the piston in the cylinder leaks from the sealing surface of the suction valve and is blown back into the suction muffler), the left and right cavity volumes are the gas cushion. In addition, the vicinity of the inlet of the suction hole 32 of the communication passage 35 of the cavity volumes 33 and 34 becomes the node of the resonance frequency, that is, the node of 630 Hz which is the lowest first mode, and the second lowest mode. Since the 1.4 KHz node is near the gas inlet end face 36a, noise during compressor operation is greatly reduced.

The vicinity of the inlet of the suction hole 32 becomes a node of the resonance frequency of 630 Hz, and the vicinity of the gas inlet end face 36a is 1.4K.
The reason why it becomes the section of the resonance frequency of Hz will be explained.

Although the international size and dimensions of a compressor used in an ordinary electric refrigerator are almost fixed, the suction muffler of the compressor is designed as shown in FIG.
5, the cavity volumes 33 and 34 are formed substantially symmetrically, and the communication passage 3 at the substantially center line of the cavity volumes 33 and 34 is formed.
5 is provided with a suction hole 32 communicating with the gas passage.

Then, the electric refrigerator equipped with this compressor is used at home under stable conditions (condensing temperature of 40
When operated at a temperature of ℃ and an evaporation temperature of −30 ° C. and detailed conditions will be described later), the position shown in FIG. 5A becomes a node of the resonance frequency of 630 Hz. This can be confirmed by the resonance mode analysis of the resonance frequency. This section is for the first-order mode of the resonance frequency.

Similarly, it can be confirmed that the node of the resonance frequency of 1.4 KHz appears at the position of (b) in FIG. This node is a node of 1.4 KHz which is the second highest mode after 630 Hz.

By disposing the suction hole 32 in the vicinity of (a) and the end face 36a of the gas inlet portion in the vicinity of (b), noise can be reduced as follows.

For noise measurement, a compressor having a cylinder volume of 5.1 cm ³ is used, and a conventional suction muffler (using the suction muffler assembly shown in FIG. 10) and the suction muffler according to the present invention are prepared. This compressor is assembled into a cooling system, and the refrigerant of HFC134a and refrigerating machine oil are enclosed.

The compressor is placed at an ambient temperature of 32 ° C. and adjusted so that the condenser (not shown) has a condensation temperature of 40 ° C. and the evaporator (not shown) has an evaporation temperature of −30 ° C. The power supply frequency is 60 cycles.

This condition is assumed when the electric refrigerator is used stably at home. After waiting for the cooling system to stabilize, a microphone is placed at a distance of 10 cm from the compressor, and SPL (Sound Pres) is set.
(Sure Level: Sound pressure level)
The noise was measured at.

The noise of the conventional compressor was as high as 57 dB at 630 Hz in the noise analysis as shown in FIG. 13, and this increased the noise and the A range was as high as 55 dB (A).

The noise of the compressor of the present invention is as shown in FIG. 13. As described above, the inlet of the suction hole has a node with a resonance frequency of 630 Hz, and the end face of the gas inlet has a value of 1.4.
Since it is a KHz node, 630 Hz to 1.4 KH
The sound up to z is reduced and the noise is suppressed. In the noise analysis, 630 Hz dropped to 30 dB, and in connection with this, the A range dropped to 47 dB (A). Therefore, the noise was significantly reduced to the extent that it was felt that the noise was halved.

Next, the cavity volume 33 on the left side and the cavity volume 34 on the right side are arranged apart from each other, and the hermetic terminal 21 fixed to the closed case 20 is provided between the cavity containers 33, 34 on the right and left sides. Due to the arrangement, the hermetic terminal can be housed between the left and right cavity volumes, which allows a compact design of the compressor, ie a compact design.

A gas inlet portion 36 of the suction muffler 30 is installed in one of the left and right cavity volumes, and the gas inlet portion 36 is made of the same material as that of the suction muffler 30 and is formed in a tube shape. The material used is HFC134a, which is a new refrigerant, and polybutylene terephthalate (PBT), which withstands ester-based refrigerating machine oil. In FIG. 5, the gas inlet portion 36 is formed in an L-shaped tube shape. The end face 36a of the gas inlet portion is arranged near the node of the secondary mode of resonance frequency, 1.4 KHz. Also, the seam 38 of the suction muffler 30
Are hermetically joined by high frequency welding 38a.
Further, an inclined return gas collision plate 43 is arranged on the side surface of the gas inlet portion 36 of the suction muffler 30, and the return gas returned from the suction tube 20a collides with the contact portion 44, so that liquid or oil in the return gas is removed. The refrigerant is separated at the time of collision and the refrigerant is sucked through the gas inlet portion 36. The inclined end 45 is integrated with the suction muffler 30 to increase strength.

In the above construction, since the gas inlet portion is made of the same material as the suction muffler, the molding is completed at once by injection molding. Therefore, while the mass productivity is excellent, the noise can be reduced by the above-mentioned node against noise and the airtightness for preventing gas leakage.

Further, as shown in FIG. 5B, the cavity volume 3
The suction tube 20a for guiding the return gas is arranged at a position opposite to the side wall 50 of the cavity portion of 3,3.

In this way, the hole 51 at the gas inlet of the suction muffler 30 is arranged on the side wall 50 of the cavity.

In the above-mentioned structure, the return gas collides from the suction tube 20a to the wide collision surface of the return gas collision portion 52, and the liquid refrigerant and the liquid refrigeration oil in the return gas are separated and fall. After that, the refrigerant gas flows into the hole 5 at the gas inlet.
Inhaled from 1.

On the other hand, since the collision portion 52 is made of a plastic material, it is difficult to conduct heat, and the sucked gas is sucked through the hole 51 at the gas inlet without being heated. Therefore, it becomes highly reliable that no failure occurs due to the suction of the refrigerant gas separated from the liquid.
On the other hand, the energy efficiency (E
ER) is improved.

Next, the gas inlet portion of the suction muffler 30 is formed as a gas inlet tube 37 by molding an elastic material such as rubber into a tube shape, and as shown in FIG. 6, the side wall 39 or the top wall 40 of the suction muffler is formed. A hole is made in a part, and it is press-fitted into this and inserted and fixed. The end surface 37a of the gas inlet tube has a resonance frequency of 1.4 KH.
It is located near the z node.

In the above construction, by using a separate elastic material for the gas inlet tube, the suction muffler can be easily manufactured into a molding die made of a plastic material or the like. Further, since the gas inlet tube is made of an elastic material, it can be assembled as an individual piece without any strict accuracy control, even if there is some variation in size, by the width of the elastic force. Therefore, the suction muffler can be manufactured at low cost.

[0046]

As described above, the present invention includes the suction muffler in which the cylinder head and the gas passage are connected to each other, and the muffler is separated substantially symmetrically to the right and left through the communication passage to form a cavity volume. A suction hole communicating with the gas passage is formed in a communication passage substantially in the center line of both cavity volumes. Then, the volume of the cavity on the left side and the volume of the cavity on the right side are approximately equal.

In the above-mentioned structure, the left and right cavity volumes function as gas cushions for the gas blown back from the cylinder, and the inlet of the suction hole of the communicating portion of the cavity volume serves as the resonance frequency node. Further, by arranging the end face of the gas inlet portion near the resonance mode node of the resonance frequency, noise during the operation of the compressor can be significantly reduced.

The left and right cavity volumes are arranged at positions distant from each other, and by providing a hermetic terminal fixed to the closed case between the left and right cavity volumes, the left and right cavity volumes are provided. Since the hermetic terminal can be housed in between, the entire compressor can be designed compact and downsized.

Further, a gas inlet of the suction muffler is installed in one of the left and right cavity volumes, and the gas inlet is provided in a tubular shape with a plastic made of the same material as the suction muffler. The end of is placed near the resonant mode node at the resonant frequency. The seam of the suction muffler is hermetically joined by high-frequency welding so that the injection molding method completes the molding at once and reduces the noise, and the airtightness prevents the sound from leaking. That is, it is possible to reduce the noise while the molding is completed at a time by injection molding and the mass productivity is excellent.

Further, the return gas is returned by arranging the suction tube for guiding the return gas to the position opposite to the side wall of the cavity of the cavity volume and arranging the hole of the gas inlet of the suction muffler on the side wall of the cavity. The liquid refrigerant and the liquid refrigerating machine oil are separated and fall by colliding with a wide collision surface of the gas collision portion. After that, the refrigerant gas is sucked through the hole at the gas inlet. On the other hand, since the collision portion is made of a plastic material, it is difficult to conduct heat, and the sucked gas is sucked through the hole of the gas inlet without being heated.

Therefore, a highly reliable compressor that does not malfunction due to the suction of the refrigerant gas separated from the liquid is obtained. On the other hand, the energy efficiency (EER) is improved because the gas is not heated.

Further, the gas inlet portion of the suction muffler is formed into a tube shape by using an elastic material such as rubber to constitute a gas inlet tube, which is fixedly provided on the side wall or the upper surface wall of the suction muffler, and the end surface of the gas inlet tube is provided. By arranging in the vicinity of the node of the resonance mode, it becomes easy to manufacture the mold for the suction muffler. Further, since the gas inlet tube is made of an elastic material, it can be assembled without strict accuracy control.

Therefore, a compressor with low noise can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a side sectional view of a hermetic electric compressor according to an embodiment of the present invention.

FIG. 2 is a top sectional view of FIG.

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

FIG. 4 is an assembly diagram of the cylinder head and the suction muffler of FIG.

5 is a partial sectional view of the suction muffler of FIG.

FIG. 6 is another modified example of FIG.

FIG. 7 is a partial sectional view of a suction muffler according to another embodiment of the present invention.

FIG. 8 is an enlarged cross-sectional view of portion a in FIG.

FIG. 9 is a side sectional view of a conventional hermetic electric compressor.

FIG. 10 is an assembly diagram of the cylinder head and the suction muffler taken along the line AA in FIG.

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

FIG. 12 is a view on arrow CC of FIG.

FIG. 13 is a noise characteristic diagram of a conventional hermetic electric compressor.

FIG. 14 is a noise characteristic diagram of the hermetic electric compressor according to the present invention.

[Explanation of symbols]

 20 Closed Case 21 Hermetic Terminal 22 Open End 23 Cylinder 24 Block 25 Piston 26 Motor 27 Valve Plate 28 Cylinder Head 29 Gas Passage 30 Suction Muffler 31 Centerline 32 Suction Hole 33 Left Side Cavity Volume 34 Right Side Cavity Volume 35 Communication Channel 36 Gas Inlet part 36a End face of gas inlet part 37 Gas inlet tube 38 Seam 38a High frequency welding 39 Side wall 40 Top wall 42 Discharge muffler

Claims (6)

[Claims] 1. A hermetically sealed case, a block including a cylinder having an open end elastically mounted in the case, a piston in the cylinder, a motor for reciprocating the piston, and a block fixed to the cylinder block. A valve plate, a cylinder head that covers the valve plate, and a suction muffler in which the cylinder head and the gas passage are connected to each other. A hermetically-operated electric compressor, characterized in that a suction hole communicating with the gas passage is formed in the communication passage of the hollow volume substantially at the center line. 2. The hermetic electric compressor according to claim 1, wherein the volume of the cavity on the left side and the volume of the cavity on the right side are substantially equal to each other. 3. The hermetic terminal fixed to a hermetically sealed case is disposed between the left and right cavity volumes at positions separated from each other and the left and right cavity volumes are separated from each other. The hermetic electric compressor according to 2. 4. A gas inlet portion of a suction muffler is installed in one of the left and right cavity volumes, and the gas inlet portion is made of the same material as the suction muffler and formed into a tube shape. 2. The hermetic electric compressor according to claim 1, wherein the end face is arranged in the vicinity of the node of the resonance mode of the resonance frequency, and the seam of the suction muffler is hermetically joined by high frequency welding. 5. A part of the side wall surface of the hollow volume which is provided with an intake tube facing the side wall surface of either the left or right side of the suction muffler to guide the return gas, and which is close to the opening of the suction tube. The hermetic electric compressor according to claim 1, wherein a hole for a gas inlet portion is provided in the. 6. The gas inlet portion of the suction muffler constitutes a tubular gas inlet tube made of an elastic material such as rubber, and is fixed to a side wall or an upper surface wall of the suction muffler, and an end face of the gas inlet tube has a resonance frequency. The hermetic electric compressor according to claim 1, wherein the hermetic electric compressor is arranged near a node of a resonance mode.