JPH0721368B2 - Refrigeration equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a solution to noise that is occasionally generated from a refrigerant compression compressor when a refrigeration system, for example, a refrigeration system incorporated in an air conditioner for automobiles is started. .

[Conventional technology]

2. Description of the Related Art An automobile air conditioner generally has a configuration in which a refrigerant compressor, a condenser, a pressure reducing device, and an evaporator are connected by a refrigerant pipe to form a closed cycle for circulating the refrigerant.

In the case of a compact-sized passenger car, such a refrigerating device is incorporated in an engine room where space is extremely small so that components such as a compressor and a condenser are dispersed.

[Problems to be solved by the invention]

In a car with a refrigeration system installed in a narrow engine room as described above, when the air conditioner is activated at a time when the temperature in the morning rises rapidly, noise is generated which may cause discomfort or anxiety. I have something to do.

The inventors of the present invention have pursued the cause of noise as described above,
The following facts have been revealed.

That is, in the situation where the morning sun starts to rise and the temperature rises rapidly, a considerable amount of liquid-phase refrigerant is retained in the compressor while the device is stopped, and this liquid refrigerant is subject to compression at startup. It was found that the above noise was generated.

The reason why a large amount of liquid refrigerant accumulates in the compressor can be estimated as follows.

In other words, since the above-mentioned components constituting the refrigeration system are different in material and size, the heat capacities are different and the installation locations are also different, which causes a difference in the temperature rise degree before starting the system. The higher temperature part of the refrigerant circulation cycle has a higher refrigerant vapor pressure than the lower temperature part,
Since the distribution of the refrigerant pressure in the cycle is biased, the refrigerant gathers toward the position where the refrigerant pressure is lower. Since the compressor has a large heat capacity, it generally satisfies the condition that the temperature rise is delayed most, and if the compressor is installed at the lowest position in the layout of the refrigeration system, the morning sun starts to rise and the temperature rises rapidly. Under such circumstances, the refrigerant in the liquid phase or condensed in each part of the cycle or in the gas phase is flowed toward the space inside the compressor due to the increase in the refrigerant vapor pressure due to the temperature rise, and the added gravity difference. It will be spread.

Therefore, installing the refrigerant compressor at the lowest point of the refrigerant circulation cycle should be avoided as much as possible. But,
In some cases, the compressor must be installed at the lowest position because of the installation space of the entire device. In such a case, movement of the liquid-phase refrigerant into the compressor is likely to occur while the apparatus is stopped, and as a result, liquid compression occurs at the time of starting the compressor, which causes a problem that noise is generated.

An object of the present invention is to provide a refrigeration system capable of satisfactorily preventing a noise problem caused by liquid compression at the time of starting the device even when the refrigerant compressor has to be mounted at a position lower than other device components. And

[Means for solving problems]

In order to achieve the above object, the refrigerating apparatus according to the present invention,
The compressor is arranged at the lowest lowest position of the refrigeration equipment components, and the refrigerant pool is arranged at a position lower than the refrigerant suction port and the refrigerant discharge port of the compressor, and the refrigerant pool is arranged in the refrigerant suction port. The technical means of communicating with the refrigerant passage is adopted.

[Operation and effect of the invention]

According to the above technical means, even if the compressor is unavoidably installed at the lowest point of the refrigerant circulation piping system due to the space where it can be installed, etc. Even if a situation occurs in which the liquid refrigerant flows into the compressor and gradually tries to stay due to fluctuations in the pressure distribution of the liquid refrigerant, the liquid-phase refrigerant flows down into the refrigerant reservoir communicating with the refrigerant suction port of the compressor. Will be collected.

Therefore, it is possible to prevent the generation of noise due to the compression of the liquid refrigerant at the time of starting the device.

The refrigerant in the refrigerant reservoir gradually vaporizes during the operation of the device and is returned to the refrigerant circulation path, so that the refrigerant reservoir can be prepared for receiving the liquid refrigerant at the next stop of the device.

〔Example〕

A specific configuration of the device of the present invention will be described below based on an embodiment shown in the accompanying drawings.

First, the overall configuration and operation of a refrigerating apparatus used in an automobile air conditioner will be described with reference to FIG. 3 as a refrigerating cycle diagram.

The compressor 1 includes a refrigerant suction port 1a and a refrigerant discharge port 1b. A low pressure side refrigerant pipe 10 serving as a refrigerant return route is connected to the suction port 1a, and a high pressure side refrigerant pipe 11 serving as a refrigerant outward route is connected to the discharge port 1b. There is.
The beginning of the pipe 10 is connected to the outlet of the pressure reducing device 5, and the end of the pipe 11 is connected to the inlet of the pressure reducing device 5. In the evaporator 6 installed in the passenger compartment, the vapor phase refrigerant that has taken the latent heat of vaporization for evaporation from the air to be cooled and has performed cooling work is sucked into the suction port 1a by the suction force of the compressor 1 After being compressed to a high pressure, it is sent out to the high pressure side refrigerant pipe 11 from the discharge port 1b. Then, the refrigerant first expands by passing through the surge tank 3 and receives a sound deadening effect, then flows into the condenser 4 and is liquefied as a cooling liquid by the action of a cooling fan (not shown). The liquefied refrigerant passes through an expansion valve 5 as a decompression device, becomes a decompressed atomized state, flows into an evaporator 6, and is cooled by air (vehicle interior air) blown to the evaporator 6 by a fan (not shown). (Or the air outside the passenger compartment) takes the latent heat of vaporization to cool the air, and returns to the vapor-phase refrigerant to be discharged to the low-pressure side refrigerant pipe 10, and passes through an accumulator 7 having a gas-liquid separation and refrigerant temporary storage function, and then a compressor. The first suction port 1a is re-sucked to complete one cycle of the refrigerant circulation.
The cool air cooled by the evaporator 6 blows out into the vehicle interior to cool the vehicle interior.

The refrigerant reservoir 2 which is a feature of the device of the present invention is attached to a position lower than the suction port 1a and the discharge port 1b so as to intervene in the low pressure side refrigerant pipe 10 connected to the suction port 1a of the compressor 1. ing.

FIG. 1 shows a first embodiment according to the present invention,
1 shows a compressor part of a refrigeration system incorporated in an automobile air conditioner and a refrigerant reservoir 2 attached so as to be connected to its suction port 1a. The compressor 1 is provided with its mounting brackets A, B and C. , And D are fixed to the engine body E of the automobile with bolts F.

The coolant reservoir 2 is configured by liquid-tightly joining a container portion 2a and a lid portion 2b made of a metal such as aluminum by a brazing method or another method. The lower end of the low pressure side refrigerant pipe 10 connected to the accumulator 7 is connected to the lower portion of the container portion 2a using a pipe joint 21, and the lid portion 2b is connected to the compressor 1
A pipe 22 for connecting to the suction port 1a is integrally formed, and is connected to the suction port 1a that opens horizontally in the side wall surface of the housing 1c of the compressor 1 using a pipe joint 23.

FIG. 2 shows a specific structure of the compressor 1 as a partial sectional view.

In this embodiment, the compressor 1 is a swash plate type multi-cylinder type. Reference numeral 13 is a housing of the compressor 1, 14 is a rotary shaft of the compressor 1, 15 is a swash plate axially fitted to the rotary shaft 14, 16
Are pistons of a plurality of refrigerant compression cylinders that are provided parallel to the axial direction of the rotary shaft 14 so as to surround the rotary shaft. By transmitting the rotational movement of the swash plate 15 to the piston 16, the piston 16 is reciprocated. Reference numeral 17 denotes a magnet clutch which intermittently transmits the rotational force of the automobile engine to the compressor 1.

Next, the operation of the apparatus of the above embodiment will be described.

In the case of the refrigerating apparatus including the main components shown in FIG. 3, when attempting to assemble each of these parts in the engine room, which is extremely limited in terms of space, under the desired mounting positional relationship, Inevitably, the compressor 1 inevitably has to be settled at the lowest position as compared with other parts.

In the air conditioner in which the compressor 1 is installed at the lowest position among the components of the refrigeration cycle as compared with the other parts, the compressor 1 having a very large heat capacity in the refrigeration device is used in the morning when the temperature suddenly rises. , The difference in temperature rise between other parts with relatively small heat capacity, the temperature rise in the compressor part is the smallest,
Therefore, the refrigerant vapor pressure in the compressor section becomes the lowest. The liquid refrigerant that has accumulated in other parts of the refrigeration system flows down toward the compressor 1 located at the lowest position and having the lowest refrigerant vapor pressure.

If the refrigerant reservoir 2 is not provided, the liquid phase refrigerant a gradually accumulates in the housing 1c of the compressor 1 for the reason described above. If the liquid level of the accumulated liquid refrigerant is below the bottom level ((a)-(a) line in FIG. 1) of the suction port 1a of the compressor 1, the space inside the housing 1c is a low pressure side refrigerant pipe. Since it is in communication with 10, the compression noise of the liquid refrigerant due to the rotation of the compressor 1 does not occur when the compressor 1 is started. When the liquid level gradually rises and rises to the level indicated by the line (b)-(b), the suction port 1a will move to the housing 1c.
Since it is completely blocked by the liquid refrigerant a accumulated therein, the compression noise of the liquid refrigerant starts to be generated with it, and the intensity of the noise is the liquid level height (c)-(c) indicated by the broken line. Gradually increases with the rise of.

However, in this embodiment, since the refrigerant reservoir 2 having the liquid refrigerant inlet is connected to the compressor 1 at a position lower than the suction port 1, the compressor 1 is directed toward the inside of the housing 1c of the compressor 1 as described above. The liquid refrigerant flowing down can be collected in the refrigerant reservoir 2 before reaching the height of the suction port 1a. Further, even if there is a liquid-phase refrigerant that flows backward toward the discharge port 1b of the compressor 1 by following the high-pressure side refrigerant distribution 11, the above-mentioned (a)-(of the refrigerant that has flowed into the compressor housing 1c B) All the liquid refrigerant that has flowed in beyond the level is discharged from the suction port 1a toward the refrigerant reservoir 2. Therefore,
By setting the desired capacity of the liquid refrigerant pool 2 based on a field test using an actual vehicle, even if the compressor 1 is started in the morning when the temperature rises rapidly, the liquid phase refrigerant compression in the compressor 1 is ensured. Therefore, the cause of noise can be reliably removed.

The liquid refrigerant that has accumulated in the refrigerant reservoir 2 at the time of starting the refrigeration system is vaporized and returned to the refrigerant circulation cycle as the system enters a steady operation state.

When an actual vehicle test was performed on the refrigerant compression noise prevention effect of the above-described apparatus using a refrigeration apparatus having a refrigerant filling amount of 1100 g, when the refrigerant pool 2 was removed, a void portion inside the compressor 1 at the time of starting the apparatus. The amount of liquid-phase refrigerant flowing into the tank reached 280 to 495cc depending on climatic conditions, and the peak value of the discharge refrigerant pressure at startup increased to 10 to 40kg / cm ² . And within the range of this refrigerant retention amount, a harsh noise of liquid refrigerant compression was generated.

On the other hand, when the refrigerant reservoir 2 according to the device of the present invention is attached, the liquid refrigerant retention amount in the compressor 1 at the time of starting the device is 130 to 1
Reduced to 85cc and the peak discharge pressure of the refrigerant at startup is 6.5
Liquid refrigerant compression noise did not occur at all, dropping to ~ 8 kg / cm ² . The vibration noise generated from the suction valve of the compressor 1 in the related art is also eliminated by the sound deadening effect of the refrigerant reservoir 2.

FIG. 4 shows the second embodiment, and the suction port 1a of the compressor 1 is shown.
The side face in the vicinity is drawn. In this embodiment, the refrigerant pool 2
Consists of a short pipe made of metal, such as an omega type, a U-shaped type, or the like, provided with an appropriate downward bent shape.
However, if there is not enough space, you may bend it sideways.

The curved refrigerant reservoir 2 has one end side connected to the compressor suction port 1a via a pipe joint 23 and the other end side connected to the low pressure side refrigerant pipe 10 via a pipe joint 24. The effective refrigerant storage volume of the refrigerant reservoir 2 is the volume in the curved pipe at the level shown by the line (a)-(b) or less.

FIG. 5 shows a third embodiment and shows a side surface in the vicinity of the suction port of the compressor 1. Pipe fitting to compressor inlet 1a
A low-pressure side refrigerant pipe 10 made of a flexible tube or a metal pipe connected via 23 is provided near the suction port 1a at the suction port 1a.
By making it hang down to a lower level, the portion shown by the dotted lines below the line (a)-(a) in the figure serves as the coolant reservoir 2.

In this figure, the pipe 10 is slackened downward, but if there is no room in the location, it is of course possible to sag it horizontally below the inlet 1a (or outlet 1b).

6 and 7 show a fourth embodiment,
The refrigerant reservoir 2 and the compressor 1 are integrated with each other. In this example, the refrigerant reservoir 2 is configured by fastening the two container members 30 and 31 with a plurality of bolts 32 to 36. In addition, bolts 34, 35, 36 are compressed housing
The refrigerant reservoir 2 is directly fixed to the compressor 1 by screwing it into the screw hole 1d of 1c, and both 1 and 2 are integrated.

Communication port formed in the upper part of one container member 30 of the refrigerant reservoir 2
By 37, the inside of the refrigerant reservoir 2 communicates with the refrigerant inlet 1a. A refrigerant suction pipe 38 connected to the low-pressure refrigerant pipe 10 is integrally formed in the lower portion of the other container member 31.

Further, the both container members 30 and 31 are formed with communication ports 39 and 40 which communicate with the refrigerant discharge port 1b of the compressor 1, and a refrigerant discharge pipe 41 which communicates with these and projects to the outside is formed in the container member. 31 is integrally molded.

The rubber O-rings 42, 43, 44, 45 act as a seal member for maintaining the airtightness of each passage connecting portion.

In the refrigeration cycle shown in FIG. 3, the accumulator 7 as a tank for gas-liquid separation and temporary storage of the refrigerant is used, and the accumulator 7 having a considerably large capacity may be provided at a location lower than the compressor 1 due to space constraints. Although the case where it is not possible is shown, the technical idea according to the present invention can be applied to a refrigeration cycle or a heat pump cycle in which a receiver is used instead of the accumulator. In addition, this refrigeration system can be freely used for purposes other than the air conditioning system for automobiles as needed.

[Brief description of drawings]

1 to 3 are views showing a first embodiment of the present invention, in which FIG. 1 is a partial sectional side view of a compressor to which a refrigerant reservoir is connected, and FIG. Partly broken perspective view, and FIG. 3 is a refrigeration cycle diagram. FIG. 4 and FIG. 5 are side views of the compressor and the refrigerant reservoir portion, respectively, for explaining the second embodiment and the third embodiment. FIG. 6 is a partial sectional side view of a compressor showing a fourth embodiment, FIG.
The figure is an exploded perspective view of FIG. 1 ... Compressor, 1a ... Refrigerant inlet, 1b ... Refrigerant outlet, 2 ... Refrigerant reservoir, 3 ... Accumulator, 4 ... Condenser, 5 ... Pressure reducing device, 6 ... Evaporator, 10, 11 ... Refrigerant circulation piping.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shogo Makino 1-1, Showa-cho, Kariya city, Aichi Prefecture, Nihon Denso Co., Ltd. (72) Inventor Hiroaki Ito 1-1-cho, Showa-cho, Kariya city, Aichi prefecture Within the corporation (56) References Japanese Patent Publication Sho 46-18693 (JP, B1)

Claims (5)

[Claims] 1. A refrigeration system in which a refrigerant compressor, a condenser, a pressure reducing device, and an evaporator are connected via a refrigerant circulation pipe, and the compressor is arranged at the lowest position among the respective parts. A refrigerating apparatus, wherein a refrigerant reservoir is arranged at a position lower than a refrigerant inlet and a refrigerant outlet of the compressor, and the refrigerant reservoir is communicated with a refrigerant passage of the refrigerant inlet. 2. The refrigerating apparatus according to claim 1, wherein the refrigerant reservoir is composed of an independent container connected to the inlet side of the refrigerant suction port. 3. The refrigerating apparatus according to claim 1, wherein the refrigerant reservoir is constituted by a part of the low-pressure side refrigerant pipe itself connected to the inlet side of the refrigerant suction port. 4. The refrigerating apparatus according to claim 1, wherein the refrigerant pool is formed integrally with the compressor. 5. The compressor is arranged in an engine room of an automobile, and the compressor is driven by an engine of the automobile to constitute a refrigerating device for an air conditioner for automobiles. The refrigeration apparatus according to any one of the first to fourth aspects.