JP2000356436A - Condenser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a condenser capable of ensuring high refrigerating effect while avoiding pressure rise of a refrigerant. SOLUTION: A multi-flow type condenser is chiefly selected as an object. Among a plurality of paths P1 to P3 the path 2 located by one on this side from the final path P3 is reduced in its tube number compared with the paths P1 to P3 located before and after the path 2, whereby they are constructed as a pressure reduction path (pressure reduction means) by lowering refrigerant pressure. A refrigerant condensed in the first path I reduced in pressure through the pressure reduction path P2, part of which is evaporated and the low pressure gas refrigerant is again condensed in the final path P3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a condenser suitably used, for example, in a refrigeration system for air conditioning of a vehicle.

[0002]

2. Description of the Related Art An air conditioning refrigeration system for a vehicle or the like generally has a vapor compression refrigeration cycle using a compressor, a condenser, an expansion valve, and an evaporator.

The state of refrigerant in such a refrigeration cycle is shown in a Mollier diagram (FIG. 12) in which pressure is plotted on the vertical axis and enthalpy is plotted on the horizontal axis. In the figure, the refrigerant is in a liquid state in a region on the left side of the liquidus line, a gas-liquid mixed state in a region between the liquidus line and the gaseous line, and a gaseous state in a region on the right side of the gaseous line. Becomes

[0004] As shown by the solid line in the figure, the refrigerant compressed by the compressor shifts from the point A to the state at the point B to become a high-temperature and high-pressure gas refrigerant. From the point C to the liquid refrigerant. Further, the liquid refrigerant is decompressed and expanded by the expansion valve, and C
The state shifts from the point D to the state at the point D, and the refrigerant becomes a low-pressure / low-temperature atomized refrigerant. This refrigerant is evaporated and vaporized by exchanging heat with air in the evaporator, and from point D to A
The state shifts to the state of the point and becomes gas refrigerant. Here, the enthalpy difference from the point D to the point A corresponds to the amount of heat acting on the cooling.
The refrigeration capacity increases.

Conventionally, in such a refrigeration cycle,
As a condenser for transferring the refrigerant from the point B to the state at the point C, a condenser including a heat exchanger called a multi-flow type is well known. In this condenser, as shown in FIG. 13, a large number of heat exchange tubes having both ends connected and connected in parallel are arranged on a pair of headers (102) (102) to form a core (101). . Further, by a partition member (103) provided in the header (102),
Many heat exchange tubes have multiple passes (P1) to (P4)
Is divided into In the condenser, the refrigerant exchanges heat with the outside air to condense while the refrigerant flows in a meandering manner sequentially through the paths (P1) to (P4).

By the way, in the above refrigeration cycle, D
As described above, the larger the enthalpy difference from the point to the point A, the larger the refrigeration capacity. Therefore, in recent years, in the condensation process of shifting the refrigerant from the point B to the point C, the condensed refrigerant is supercooled to a temperature several degrees lower than the point C to increase the heat release amount,
Development of condensers based on the idea of increasing the enthalpy difference during evaporation has been promoted.

As a proposal for such improvement, there has been proposed a condenser with a receiver tank in which a receiver tank is disposed between a condenser section and a subcooling section.

As shown in FIG. 14, the condenser with a receiver tank of the proposed example has a multi-flow type heat exchanger core (111) and a receiver tank (113) attached to one of the headers (112). The upstream side of the heat exchanger core (111) is configured as a condensing section (111C), and the downstream side is configured as a supercooling section (111S). In this condenser, the refrigerant exchanges heat with the outside air to condense while flowing in a meandering manner through the paths (P1) to (P3) of the condensing section (111C) in order. And the condensed refrigerant into the receiver tank (1
13), gas-liquid separation is performed, and only the liquid refrigerant is supercooled (1).
11S) for supercooling.

In the refrigeration cycle using such a condenser, as shown by the dotted line in FIG. 12, the refrigerant compressed by the compressor shifts from the point A to the state at the point Bs to become a high-temperature and high-pressure gas refrigerant. Subsequently, the condensing section (111
After being cooled by C), the state shifts from the point Bs to the point Cs1 to become a liquid refrigerant. Further, after passing through the receiver tank (112), the liquid refrigerant is supercooled by the supercooling section (111S), and shifts from the Cs1 point to the Cs2 point to become a complete liquid refrigerant. Then, this liquid refrigerant is decompressed and expanded by the expansion valve, and shifts from the point Cs2 to the state of the point Ds,
It becomes a refrigerant in an atomized state, is evaporated and vaporized in an evaporator, shifts from a point Ds to a point A, and becomes a gas refrigerant.

In this refrigeration cycle, the condensed refrigerant is supercooled as shown by Cs1 to Cs2, so that the enthalpy difference during evaporation (Ds to A) becomes larger than the enthalpy difference during evaporation in a normal refrigeration cycle. It becomes larger than (DA) and an excellent refrigeration effect can be obtained.

[0011]

The conventional condenser with a receiver tank described above is, like the existing condenser shown in FIG. 13, installed in a limited space in an automobile, and has a basic structure. Is the same size as the existing condenser. However, the conventional condenser with a receiver tank has a configuration in which the lower side of the core (111) is configured as a supercooling section (111S) that does not contribute to condensation. The condensing section (111C) corresponds to the formation of the supercooling section (111S) in the
And condensing capacity decreases. Therefore, in order to reliably condense the refrigerant with this low condensing capacity, it is necessary to increase the refrigerant pressure by a compressor and send the high-temperature and high-pressure refrigerant to the condensing section (111C). As a result, the refrigerant pressure in the refrigeration cycle, especially in the condensing area, increases, and in fact,
As shown in the Mollier diagram of FIG. 12, in the refrigeration cycle using the conventional condenser with the receiver tank, the refrigerant pressure in the condensing and supercooling region (Bs to Cs2) is higher than that in the normal refrigeration cycle. Has become.

As described above, the conventional condenser with a receiver tank requires a high refrigerant pressure, so that, for example, the load on the compressor is increased, and the compressor is required to have a large size and high performance. In addition to the increase in weight and weight, there is a problem that the fuel efficiency at the time of mounting on a vehicle is reduced and the cost is further increased.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a condenser capable of obtaining a high refrigerating effect while avoiding an increase in the pressure of the refrigerant.

[0014]

To achieve the above object, a condenser according to a first aspect of the present invention comprises a refrigerant inlet, a refrigerant outlet,
A refrigerant path for condensing the refrigerant flowing from the refrigerant inlet to the refrigerant outlet while guiding the refrigerant to the refrigerant outlet; and a pressure reducing means provided in the refrigerant path for reducing the refrigerant pressure.

The condenser of the present invention reduces the pressure of the refrigerant by the pressure reducing means in the process of condensing the refrigerant. The condenser, together with the compressor, the evaporator, the expansion valve, the receiver tank, etc., is used for air conditioning of vehicles. This is to build a refrigeration system.

In the refrigeration system using the condenser of the present invention, as shown by the solid line in FIG. 7, the refrigerant is compressed by the compressor, shifts from point A to point B, Gas refrigerant. Subsequently, the refrigerant is condensed and shifts from the point B to the state of the point Ct1 to become a liquid refrigerant. Further, the liquid refrigerant is decompressed by the decompression means and shifts from the point Ct1 to the point Ct2 to become a low-temperature and low-pressure gas refrigerant, and the gas refrigerant is recondensed and shifts from the point Ct2 to the point Ct3. . After the refrigerant thus condensed is separated into gas and liquid by the receiver tank, only the liquid refrigerant is decompressed and expanded by the expansion valve, and shifts from the Ct3 point to the Dt point to become a low-pressure, low-temperature refrigerant in an atomized state, Thereafter, the heat is exchanged with air in the evaporator to be evaporated and vaporized, and the state shifts from the point Dt to the point A to become a gas refrigerant.

The condenser according to the present invention comprises a primary condensation (B to Ct1) and a decompression (Ct1 to Ct2) in the refrigeration cycle.
And secondary condensation (Ct2 to Ct3).

Therefore, in this condenser, the refrigerant dissipates heat by primary condensation to increase the heat absorbing ability, and then the refrigerant is decompressed and recondensed, thereby further dissipating heat to further increase the heat absorbing ability. Increase. For this reason, the enthalpy difference at the time of evaporation can be increased, and an excellent refrigeration effect can be obtained. For example, a refrigeration cycle using the condenser of the present invention has an enthalpy difference (Dt-
A) is that an excellent refrigeration effect can be obtained to the same degree as the enthalpy difference (Ds to A) at the time of refrigerant evaporation in a refrigeration cycle using the condenser with a receiver tank (see the broken line in FIG. 7). it can.

Moreover, the condenser of the present invention radiates the refrigerant by the primary condensation and the secondary condensation accompanied by the phase change. By supercooling without accompanying, it is possible to radiate heat more efficiently as compared with the case where the heat radiation amount of the liquid refrigerant is improved. In other words, the condenser of the present invention can be configured with almost the entire area as the condenser's original condensing section and can efficiently radiate the refrigerant, and thus can obtain excellent condensing ability. Therefore, the refrigerant can be reliably condensed without increasing the pressure of the refrigerant in the refrigeration cycle, and the load on the compressor can be reduced.
Therefore, it is possible to prevent the compressor from being increased in size, to reduce the size and weight of the entire refrigeration system, to improve fuel efficiency when the vehicle is mounted, and to further reduce the cost.

In the condenser of the present invention, it is not always necessary to completely vaporize the refrigerant by the decompression means, and the liquid refrigerant condensed on the upstream side of the decompression means is kept in a liquid state without being vaporized by the decompression means. In some cases, it may be guided downstream as it is.

However, in order to effectively prevent the rise of the refrigerant pressure, it is preferable that at least a part of the liquid refrigerant is vaporized and recondensed (secondary condensation) by the pressure reducing means.

That is, in the condenser of the present invention, the refrigerant condensed on the upstream side of the decompression means in the refrigerant path is decompressed by the decompression means and at least a part thereof is vaporized. It is preferable that the refrigerant be condensed downstream of the pressure reducing means in the refrigerant path.

Further, in the present invention, a configuration is adopted in which the cross-sectional area of the refrigerant passage of the pressure reducing means is set to be smaller than the cross-sectional area of the refrigerant passage on the upstream and downstream sides of the pressure reducing means. The above configuration can be reliably realized.

On the other hand, the second invention specifies a multi-flow type condenser capable of forming a refrigeration system unique to the first invention.

That is, in the second invention, a core is formed by disposing a plurality of heat exchange tubes connecting both ends to both headers between a pair of headers arranged in parallel with each other at intervals. The plurality of heat exchange tubes are divided into a plurality of paths by a partition member provided inside the header, and a refrigerant path in which a refrigerant sequentially passes through each of the paths is formed. Among them, a gist is provided in which a pressure reducing means for reducing the refrigerant pressure is provided in the middle of the refrigerant path between the first pass and the final pass.

In the condenser of the second invention, a unique refrigeration cycle can be formed, similarly to the condenser of the first invention, and the refrigerant pressure in the refrigeration cycle can be increased in the same manner as described above. An excellent refrigeration effect can be obtained without causing this.

In the second invention, the path is 3
It is possible to adopt a configuration in which at least one pressure path is provided and an intermediate path between the first path and the final path is formed as a decompression path constituting the decompression means.

Further, in the second invention, it is preferable that a path immediately before the last pass is constituted as the decompression pass. That is, in this case, the primary condensation and the secondary condensation can be performed efficiently.

Further, in the second invention, a plurality of passes between the first pass and the final pass may be constituted as the decompression passes.

In particular, in the second invention, the ratio of the total passage sectional area of all the paths arranged on the upstream side of the decompression path to the total passage sectional area of all the paths arranged on the downstream side is: It is preferable to adopt a configuration that is set to 65 to 90%: 35 to 10%.

That is, if the passage cross-sectional area of the path on the upstream side of the decompression path is too large and the passage cross-sectional area of the path on the downstream side of the decompression path is too small, it may be difficult to reliably perform the secondary condensation. In some cases, the heat radiation of the refrigerant cannot be performed efficiently. Conversely, if the passage cross-sectional area of the path on the upstream side of the decompression path is too small, it may be difficult to sufficiently perform the primary condensation, and the heat radiation of the refrigerant may not be performed efficiently.

In the present invention, in order to realize a specific configuration of the decompression means, the total passage cross-sectional area of the decompression path is set smaller than each of the total passage cross-sections of the paths before and after the decompression path. It is preferable to adopt the configuration made.

In this case, the total passage cross-sectional area of the decompression path is preferably set to 10 to 50% with respect to the total passage cross-section of the path immediately before the decompression pass, and more preferably, the lower limit value. Is set to 20% or more and the upper limit is set to 30% or less. That is, if the passage cross-sectional area of the decompression path is too small with respect to the path before the pressure reduction path, the refrigerant is likely to stay before the pressure reduction path, and the circulation of the refrigerant may not be performed smoothly. Conversely, if the passage cross-sectional area of the pressure reduction path is too large, the refrigerant may not be sufficiently depressurized in the pressure reduction path.

Further, the total passage cross-sectional area of the decompression path is preferably set to 10 to 55% with respect to the total passage cross-sectional area of the path immediately after the decompression pass, and more preferably the lower limit is set to 20%. As described above, the upper limit is preferably set to 30% or less. That is, if the passage cross-sectional area of the decompression path is too small, the passage cross-section of the path on the downstream side of the decompression path becomes unnecessarily large, and a useless space that does not contribute to condensation occurs, and heat may not be efficiently dissipated. There is. Conversely, if the passage cross-sectional area of the decompression path becomes too large and the passage cross-section of the downstream path on the decompression path becomes small, the secondary condensation may not be sufficiently performed.

Further, in the present invention, it is preferable to adopt a configuration in which the total passage cross-sectional area of the decompression path is set to 2 to 10% with respect to the total passage cross-sectional area of all the passes.

That is, if the passage cross-sectional area of the decompression path is too small, the refrigerant tends to stay before the decompression path, and the circulation of the refrigerant may not be carried out smoothly. The refrigerant may not be sufficiently depressurized.

On the other hand, in the present invention, the heat exchange tubes constituting the decompression path have an equivalent diameter (equivale) with respect to the heat exchange tubes constituting the paths before and after the decompression path.
nt diameter) can be adopted.

Here, the equivalent diameter is a value obtained by dividing four times the cross-sectional area of the flow path by the perimeter of wetting. That is, as the equivalent diameter is smaller, the flow rate of contact per unit area increases, and the heat exchange rate improves.

In the present invention, in order to realize a specific configuration of the pressure reducing means, the heat exchange tubes constituting the pressure reducing path are separated from the heat exchanging tubes constituting the paths before and after the pressure reducing path by a passage. The configuration in which the area is set to be small, the inner diameter of the heat exchange tube constituting the decompression path,
Adopt a configuration that is set to be partially smaller, or a configuration in which the number of heat exchange tubes that form the decompression path is set smaller than the number of heat exchange tubes that form paths before and after the decompression path. It is possible.

In the condenser of the present invention, the total number of heat exchange tubes is generally about 20 to 50. Therefore, in order to form a decompression path and other paths with a passage cross-sectional area unique to the present invention as described above, the number of heat exchange tubes constituting the decompression path is set to 1 to 5. Configuration, a configuration in which the number of heat exchange tubes constituting a path before the decompression path is set to 3 to 40, or a heat exchange tube constituting a path after the decompression path. The number is 3 to 12, preferably 3
It is preferable to adopt a configuration in which the number is set to ８8.

In the present invention, it is also possible to adopt a configuration in which the heat exchange tubes constituting the pressure reducing path are formed in a non-linear manner. For example, a meandering tube used in a serpentine condenser can be used as a tube constituting the decompression path.

Further, in the present invention, a path downstream of the pressure reducing path includes a condensing section for condensing the gas refrigerant passing through the pressure reducing means, and a supercooling section for supercooling the liquid refrigerant passing through the pressure reducing means. And a configuration having the following.

[0043]

FIG. 1 is a front view showing a condenser according to an embodiment of the present invention, and FIG. 2 is a configuration diagram of a refrigerant circuit of the condenser.

As shown in both figures, this condenser has a multi-flow type heat exchanger as a basic configuration.
The core (10) is provided with a pair of left and right headers (11) (11) that are spaced apart and face each other along the vertical direction. Between the pair of headers (11) and (11), a large number (14) of flat tubes (12) as heat exchange tubes along the horizontal direction are connected at both ends thereof to both headers (11).
In a state communicating with (11), they are arranged side by side at predetermined intervals in the vertical direction. Further, corrugated fins (13) are arranged between the flat tubes (12) and outside the outermost flat tubes (12). A band-shaped side plate (14) is provided outside the outermost fin (13) to protect the fin (13).

As the flat tube (12), as shown in FIG. 3, a harmonica tube having a plurality of refrigerant passages (12a) provided therein is generally used.

In the present invention, as the heat exchange tube, as shown in FIGS. 4 and 5, a plurality of refrigerant passages (12a) are provided inside, and a partition wall between adjacent refrigerant passages (12a). A flat tube or the like in which a plurality of communication holes (12c) communicating adjacent refrigerant passages are formed in 12b) can also be suitably used.

Also, one side (right side) header (11)
Is provided with a refrigerant inlet (11a) made of a union nut or the like, and a lower end of the header (11) on the other side (left side) is provided with a refrigerant outlet (11b) made of a union nut or the like. .

Further, as shown in FIGS. 1 and 2, a partition member (15) for partitioning the inside of the header is provided between the tenth and eleventh flat tubes (12) in the right header (11). A partition member (16) for partitioning the inside of the header is provided between the eleventh and twelfth flat tubes (12) in the left header (11). Thereby, the first pass (P1) is formed by the first to tenth flat tubes (12) from the top, and the second pass (P2), that is, the decompression pass () is formed by the eleventh flat tube (12). Pressure reducing means), and from the twelfth
The third pass (P) with up to the fourth flat tube (12)
3), that is, the final pass is formed.

In the condenser (1), the core (1)
0) is a first condensing section (C1) on the upper side and a second condensing section (C2) on the lower side of the second path (P2) as a pressure reducing means.
Is configured as

In this condenser (1), the refrigerant inlet (1)
The refrigerant flowing into the header (11) from 1a) is the first refrigerant.
By passing through the third path (P1) to (P3) in this order, it flows in a meandering manner in the core (10) and flows out from the refrigerant outlet (11b).

As shown in FIG. 6, the condenser (1) having the above configuration is connected to a compressor (2), a receiver tank (5), an expansion valve (3), and an evaporator (4) by a refrigerant pipe. Therefore, it is adopted as a vehicle refrigeration system.

In this refrigeration system, the high-temperature and high-pressure gas refrigerant discharged from the compressor (2) flows into the condenser (1) and passes through the first path (P1), that is, the first condenser (C1). Then, it is condensed and liquefied, changes from the point B state in FIG. 7 to the Ct1 state, and flows into the pressure reduction path (P2).

Here, the pressure reduction path (P2) has a smaller number of tubes and a smaller total passage sectional area than the upstream path (P1), so that the refrigerant passes through the pressure reduction path (P2).
When passing through 2), the flow velocity increases and the pressure is reduced to partially evaporate, the state changes from the Ct1 point state in FIG. 7 to the Ct2 state, and is guided to the final pass (P3), that is, the second condensing section (C2). Then, the low-pressure gas refrigerant flows in the second condensing section (C2).
It is cooled again and condensed, losing a large amount of heat.
The state changes from the point state to the Ct3 state.

The refrigerant that has lost a large amount of heat and has increased heat absorption capacity is separated into gas and liquid in the receiver tank (5), and only the liquid refrigerant is decompressed and expanded by the expansion valve (3). The state changes from the Ct3 point state to the Dt point state. afterwards,
The low-pressure, low-temperature refrigerant in the atomized state is sent to the evaporator (4), where it evaporates and evaporates by exchanging heat with the air inside the vehicle, and changes from the Dt point state to the A point state. Return.

As described above, in the condenser (1) of the present invention, the refrigerant is condensed in the first condenser (C1), then decompressed and further condensed in the second condenser (C2). Since the amount of heat release (heat absorption capacity) of the refrigerant can be increased stepwise, the enthalpy difference (Dt to A) at the time of evaporation is reduced by the enthalpy difference (Ds to A) in a refrigeration cycle using a conventionally proposed condenser with a receiver tank. As large as A), it is possible to obtain a large freezing effect.

Moreover, in the condenser (1) of the present embodiment, after the heat is radiated by the primary condensation (point B to Ct1), the refrigerant is discharged by the secondary condensation (Ct2 to Ct3) accompanied by a phase change. Since the heat quantity is improved, compared with the case of improving the heat release quantity of the liquid refrigerant by supercooling without phase change, for example, as in the condenser with a receiver tank proposed in the past, it is necessary to dissipate heat more efficiently. Can be. That is, the condenser of the present embodiment covers almost the entire area of the condenser (C
1) Since it is configured as (C2), it is possible to efficiently radiate the refrigerant, so that it is possible to obtain excellent condensing ability. Therefore, the refrigerant can be reliably condensed without increasing the pressure of the refrigerant in the refrigeration cycle, and the load on the compressor can be reduced. Therefore, it is possible to prevent the compressor from being increased in size, to reduce the size and weight of the entire refrigeration system, to improve fuel efficiency when the vehicle is mounted, and to reduce the cost.

Furthermore, in the condenser (1) of the present embodiment, when the refrigerant entering the pressure reduction path (P2) is not liquefied without fail, gas is mixed into the refrigerant flowing through the pressure reduction path (P2). Since the volume is large, the pressure reduction path (P
The resistance flowing through 2) increases, and the flow of the refrigerant is obstructed by the pressure reduction path (P2), and the flow rate decreases. When the flow rate is reduced in this manner, the condensation load on the upstream side is reduced, and the condensation is promoted, and only the complete liquefied refrigerant is led to the pressure reduction path (P2). That is, the pressure reduction path (P2) has a function of self-control of the flow rate of the refrigerant, and acts as an orifice tube. For this reason, the decompression path (P2) is always kept in the best condition, and while being depressurized, at the same time as being cooled, a part of the vaporized gas becomes a gas and is led to the final path (P3) and recondensed as described above. Therefore, the heat radiation amount of the refrigerant can always be kept high, and an excellent refrigeration effect can be maintained.

As described above, the condenser (1) of the present embodiment
According to the method, an excellent refrigeration effect can be obtained while avoiding an increase in refrigerant pressure.

Further, in the condenser (1) of the present embodiment, unlike the condenser with a receiver tank of the above-mentioned conventional proposal, a receiver tank (5) which is independent of the core is used as the receiver tank (5). Therefore, the installation place of the receiver tank (5) is not restricted, and a complicated structure such as a condenser with a receiver tank conventionally proposed is not required.
The structure can be simplified, and the cost and space can be further reduced.

By the way, in the present invention, the total passage cross-sectional area of the pressure reduction path (P2) is set to be equal to or smaller than the total path (P1).
It is preferable to set the total passage sectional area of (P3) to 2 to 10%. That is, if the total passage cross-sectional area of the pressure reduction path (P2) is too large, the pressure reduction path (P
In 2), the refrigerant cannot be sufficiently depressurized,
For example, there is a possibility that the self-control function as the orifice tube cannot be sufficiently exhibited. Conversely, if the total passage cross-sectional area of the pressure reduction path (P2) is too small, the refrigerant may not flow smoothly and the circulation of the refrigerant may be insufficient.

Here, in the above embodiment, the total passage cross-sectional area (%) of the decompression path (P2) with respect to the total passage cross-sectional area of all the paths (P1) to (P3) is (the number of tubes of the decompression path) / ( Number of tubes in all passes) x 10
Since it is represented by 0, 1/14 × 100 = 7.14%, which is set within the above-mentioned preferred range.

Further, in the present invention, a tube constituting a decompression path may be of a different configuration in order to enhance the decompression effect with respect to other tubes.
For example, as shown in FIG.
2) a plurality of small circular refrigerant passages (12)
The hole passage type harmonica tube in which a) is provided in parallel may be used.

Further, in the present invention, the number of passes and the number of tubes in each pass, particularly the number of tubes in the decompression pass, are not limited. For example, as shown in FIG. (P4), and the third pass (P
3) may be a decompression path (decompression means) composed of two tubes.

Further, in the present invention, two or more pressure reduction paths may be provided. For example, as shown in FIG. 10, the headers (11) and (11) are
(17), four passes (P1) to (P
4), one of which is a tube (1).
The second and third passes (P2) and (P3) composed of 2) may be configured as decompression passes.

In the present invention, it is not always necessary to use a straight tube as a tube constituting the decompression path. A meandering tube or a capillary tube used in a serpentine heat exchanger may be replaced with a tube for the decompression path. Can also be used as a tube.

In the present invention, the pressure reducing means does not necessarily need to be constituted by the heat exchange tube itself, but may be provided with a pressure reducing means such as a partition plate with an orifice or a throttle valve in the tube. good.

Further, in the present invention, the decompression means does not necessarily need to be provided in the heat exchange tube (path), but may be provided in the header. In short, the decompression means is provided in the middle of the refrigerant path from the refrigerant inlet to the refrigerant outlet. What is necessary is just to provide a decompression means.

[0068]

As described above, according to the condenser of the present invention, since the pressure is reduced in the process of condensing the refrigerant, the amount of heat radiation of the refrigerant can be increased without increasing the pressure of the refrigerant. Thus, there is an effect that an excellent refrigeration capacity can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view showing a condenser according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a refrigerant circuit in the condenser of the embodiment.

FIG. 3 is a cross-sectional view showing a flat tube applied as a heat exchange tube of the condenser of the embodiment.

FIG. 4 is an exploded perspective view showing a flat tube applicable as a modified example of the heat exchange tube in the present invention.

5 is a view showing the flat tube of FIG. 4, wherein FIG. 5 (a) is a front sectional view and FIG. 5 (b) is a side sectional view.

FIG. 6 is a schematic block diagram showing a refrigeration system to which the condenser of the embodiment is applied.

FIG. 7 is a Mollier chart in a refrigeration cycle using the condenser of the present invention.

FIG. 8 is a cross-sectional view showing a circular passage type flat tube showing a modified example of the vacuum path tube in the present invention.

FIG. 9 is a configuration diagram of a refrigerant circuit of a condenser according to a modification of the present invention.

FIG. 10 is a front view showing a condenser according to another modification of the present invention.

FIG. 11 is a configuration diagram of a refrigerant circuit in a condenser according to another modification.

FIG. 12 is a Mollier chart in a conventional refrigeration cycle.

FIG. 13 is a configuration diagram of a refrigerant circuit in a conventional multi-flow condenser.

FIG. 14 is a configuration diagram of a refrigerant circuit in a condenser with a receiver tank according to a conventional proposal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Condenser 10 ... Core 11 ... Header 12 ... Flat tube (heat exchange tube) 15, 16, 17 ... Partition member C1, C2 ... Condensing part P1-P4 ... Pass

Claims (21)

[Claims] 1. A refrigerant inlet, a refrigerant outlet, a refrigerant path leading to the refrigerant outlet while condensing the refrigerant flowing from the refrigerant inlet, and a refrigerant path provided in the middle of the refrigerant path for reducing refrigerant pressure. And a pressure reducing means. 2. The refrigerant condensed on the upstream side of the depressurizing means in the refrigerant path is decompressed by the depressurizing means and at least partially vaporized, and the low-pressure gas refrigerant is discharged from the depressurizing means in the refrigerant path. The condenser according to claim 1, wherein the condenser is also configured to be condensed downstream. 3. The condenser according to claim 1, wherein a cross-sectional area of the refrigerant passage of the decompression unit is set smaller than a cross-sectional area of the refrigerant passage on the upstream and downstream sides of the decompression unit. . 4. A core is formed between a pair of headers arranged in parallel at a distance from each other, and a plurality of heat exchange tubes connecting both ends thereof to the headers are arranged to form a core. By the provided partition member,
The plurality of heat exchange tubes are divided into a plurality of paths,
In the condenser in which a refrigerant path through which the refrigerant passes sequentially in each of the paths is formed, in order to lower the refrigerant pressure in the refrigerant path between the first path and the final path among the plurality of paths. Wherein the pressure reducing means is provided. 5. The method according to claim 1, wherein three or more paths are provided, and
5. The condenser according to claim 4, wherein an intermediate path between the path and the final path is formed as a decompression path constituting the decompression means. 6. The condenser according to claim 5, wherein a path immediately before the final path is configured as the decompression path. 7. The condenser according to claim 5, wherein a plurality of passes between the first pass and the final pass are configured as the pressure reducing pass. 8. The ratio of the total passage cross-sectional area of all the paths arranged on the upstream side of the decompression path to the total passage cross-sectional area of all the paths arranged on the downstream side is 65 to 90.
The condenser according to any one of claims 5 to 7, wherein% is set to 35 to 10%. 9. A total passage cross-sectional area of the decompression path is:
The condenser according to any one of claims 5 to 8, wherein the total passage cross-sectional area of each of the paths before and after the pressure reduction path is set to be smaller. 10. The condenser according to claim 9, wherein a total passage cross-sectional area of the decompression path is set to 10 to 50% with respect to a total passage cross-sectional area of a path immediately before the decompression pass. 11. The total passage cross-sectional area of the decompression path is set to 10 to 55% with respect to the total passage cross-sectional area of a path after the decompression path.
0 condenser. 12. The total passage cross-sectional area of the decompression path is 2 to 10 with respect to the total passage cross-sectional area of all the passes.
The condenser according to any one of claims 5 to 7, wherein the condenser is set to%. 13. The heat exchange tube constituting the decompression path has an equivalent diameter smaller than that of a heat exchange tube constituting a path before and after the decompression path. The condenser according to any one of the above. 14. The heat exchange tube constituting the pressure reduction path has a passage cross-sectional area smaller than that of the heat exchange tube constituting the path before and after the pressure reduction path. Condenser. 15. The condenser according to claim 5, wherein an inner diameter of the heat exchange tube constituting the pressure reducing path is partially set to be small. 16. The method according to claim 5, wherein the number of heat exchange tubes constituting the decompression path is set smaller than the number of heat exchange tubes constituting paths before and after the decompression path. Condenser. 17. The condenser according to claim 16, wherein the number of heat exchange tubes constituting the pressure reduction path is set to 1 to 5. 18. The condenser according to claim 16, wherein the number of heat exchange tubes constituting one path before the decompression path is set to 3 to 40. 19. The condenser according to claim 16, wherein the number of heat exchange tubes constituting one pass after the decompression pass is set to 3 to 12. 20. The condenser according to claim 5, wherein the heat exchange tube constituting the pressure reduction path is formed in a non-linear shape. 21. A path downstream of the decompression path,
A condenser for condensing the gas refrigerant that has passed through the decompression means,
The condenser according to any one of claims 5 to 7, further comprising a subcooling unit that supercools the liquid refrigerant that has passed through the pressure reducing unit.