JP2016118314A - Evaporator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporator capable of suppressing occurrence of a slug flow of a refrigerant in a heat exchange tube.SOLUTION: At one end part in the longitudinal direction in a leeward side upper header part 5 of an upper header tank 2 of the evaporator, a refrigerant inlet 7 is provided. Also, at the entire leeward side upper header part 5, a refrigerant inflow partition 18 in which a refrigerant flows in through the refrigerant inlet 7 is provided. In the refrigerant inflow partition 18, a porous sheet 19 is arranged so as to partition the inside of the refrigerant inflow partition 18 into an upper space 18a which the refrigerant inlet 7 faces, and a lower space 18b which a heat exchange tube 13 faces. The porous sheet 19 is made of punching metal, a wire net or a woven fabric. Opening of the porous sheet 19 is 0.05-2.5 mm, and an aperture ratio is 30-70%.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an evaporator used in a car air conditioner that is a refrigeration cycle mounted on an automobile.

  In this specification, the term “aluminum” includes aluminum alloys in addition to pure aluminum. In this specification and claims, the top and bottom of FIGS. 1 and 5 are the top and bottom.

  As an evaporator used in a car air conditioner that is a refrigeration cycle mounted on an automobile, a plurality of aluminum extrusions arranged in parallel at intervals in a state where the longitudinal direction is directed in the vertical direction and the width direction is directed in the ventilation direction A flat heat exchange pipe made of a profile, and a pair of upper and lower sides having two header portions arranged on both upper and lower sides of the heat exchange pipe in a state where the longitudinal direction is directed to the arrangement direction of the heat exchange pipe and arranged in the ventilation direction It includes a header tank and fins arranged between heat exchange pipes adjacent to each other in the longitudinal direction of the header tank, and a plurality of heat exchanges between the leeward header portions and between the leeward header portions of both header tanks. A pipe is arranged and connected to both header parts, a refrigerant inlet is provided at one end of the leeward header part of the upper header tank, and a refrigerant inlet in the leeward header part of the upper header tank A refrigerant outlet is provided at the same end, and the refrigerant flowing into the leeward header portion of the upper header tank from the refrigerant inlet flows downward in the leeward heat exchange pipe and flows into the leeward header portion of the lower header tank, Next, the air enters the windward header portion of the lower header tank through the communication portion, flows upward in the heat exchange pipe on the windward side, enters the windward header portion of the upper header tank, and then flows out from the refrigerant outlet. An evaporator is known (see Patent Document 1).

  However, according to the evaporator described in Patent Document 1, relatively large bubbles may be included in the refrigerant that has flowed into the leeward header portion of the upper header tank from the refrigerant inlet, and the large bubbles are at least part of the leeward heat. By entering the exchange pipe, a slag flow in which the gas phase and the liquid phase are separated is generated in the heat exchange pipe, and the heat exchange efficiency between the refrigerant in the heat exchange pipe where the slag flow is generated and the air passing through the evaporator May become insufficient.

JP-A-2005-43039

  An object of the present invention is to provide an evaporator that solves the above-described problems and can suppress generation of a slag flow of a refrigerant in a heat exchange pipe.

  In order to achieve the above object, the present invention comprises the following aspects.

1) A plurality of heat exchange tubes arranged in parallel with a gap between each other with the longitudinal direction facing up and down, and both upper and lower sides of the heat exchange tube with the longitudinal direction oriented in the direction of arrangement of the heat exchange tubes And an evaporator having a pair of upper and lower header tanks having at least one header portion connected to both ends of the heat exchange pipe,
One header portion in the upper header tank is provided with a refrigerant inlet and a refrigerant inflow compartment into which the refrigerant flows through the refrigerant inlet, and the refrigerant inlet faces the refrigerant inflow compartment in the refrigerant inflow compartment. An evaporator in which a multi-hole sheet is arranged so as to partition into a space and a space where a heat exchange tube faces.

  2) A refrigerant inlet is provided at one end of the header portion in the longitudinal direction, a refrigerant inflow section is provided at a portion of the header section in the longitudinal direction of the refrigerant inlet, and the refrigerant inflow section is divided into upper and lower spaces by a multi-hole sheet. The evaporator according to 1), wherein the evaporator is partitioned and the refrigerant inlet faces the upper space of the refrigerant inflow compartment, and the heat exchange pipe faces the lower space of the refrigerant inflow compartment.

  3) The evaporator according to 1) or 2) above, wherein the multi-hole sheet is made of a punching metal, a wire mesh, or a woven fabric, and the multi-hole sheet has an opening of 0.05 to 2.5 mm and an opening ratio of 30 to 70%.

  According to the evaporators 1) to 3), the one header portion in the upper header tank is provided with the refrigerant inlet and the refrigerant inflow section through which the refrigerant flows through the refrigerant inlet. Since the multi-hole sheet is arranged so as to partition the refrigerant inflow compartment into a space where the refrigerant inlet faces and a space where the heat exchange pipe faces, a large amount of refrigerant has flowed into the refrigerant inflow compartment from the refrigerant inlet. When passing through the hole sheet, the relatively large bubbles contained therein are refined to become fine bubbles, and the fine bubbles are uniformly dispersed in the liquid phase. Therefore, the generation of the slag flow in all the heat exchange tubes is suppressed, and the heat exchange efficiency is improved.

  According to the evaporator of 3) above, the multi-hole sheet is made of punching metal, wire mesh or woven fabric, and the multi-hole sheet has an opening of 0.05 to 2.5 mm and an opening ratio of 30 to 70%. From the above, the effect of refining relatively large bubbles contained in the refrigerant flowing into the refrigerant inflow compartment to form fine bubbles and the effect of uniformly dispersing the fine bubbles in the liquid phase become remarkable.

It is the perspective view which abbreviate | omitted one part which shows the whole structure of the evaporator of this invention. FIG. 2 is a vertical cross-sectional view of a leeward side upper header portion in which a part of the main part of the evaporator of FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the following description, the downstream side in the ventilation direction (the direction indicated by the arrow X in FIG. 1) is the front and the opposite side is the rear, and when viewed from the upstream side in the ventilation direction, up and down, left and right (FIGS. 1 and 2). The top and bottom, left and right) are called left and right.

  Furthermore, in the following description, the term “aluminum” includes aluminum alloys in addition to pure aluminum.

  FIG. 1 shows the overall configuration of an evaporator according to the present invention, and FIG. 2 shows the configuration of the main part thereof.

  In FIG. 1, the evaporator (1) is composed of an aluminum upper header tank (2) and an aluminum lower header tank (3) which are spaced apart in the vertical direction with the longitudinal direction directed to the left and right direction. And a heat exchange core section (4) provided between the header tanks (2) and (3).

  The upper header tank (2) is integrated with the leeward upper header part (5) located on the front side (downstream side of the ventilation direction) and the rear side (upstream side of the ventilation direction) and integrated with the leeward side upper header part (5) And a windward upper header section (6). A refrigerant inlet (7) is provided at the right end of the leeward upper header (5), and a refrigerant outlet (8) is provided at the right end of the leeward upper header (6). The lower header tank (3) includes a leeward lower header portion (9) located on the front side, and an upwind lower header portion (11) located on the rear side and integrated with the leeward lower header portion (9). It has. The leeward lower header portion (9) and the leeward lower header portion (11) are joined across the right ends of the lower header portions (9) and (11), and the inside is a communication member. (12) through.

  The heat exchange core (4) has two flat heat exchange pipes (13) whose longitudinal direction faces the up-down direction and whose width direction faces the ventilation direction (front-rear direction) and is spaced from each other in the ventilation direction. ) Are arranged in parallel at intervals in the thickness direction (left and right direction) of the heat exchange pipe (13), and the pipe sets (14) adjacent to each other in the left and right direction are arranged. A gap is formed between them, and the entire gap is a ventilation gap (15). The upper end of the leeward heat exchange pipe (13) is connected to the leeward upper header (5) and the lower end is connected to the leeward lower header (9). The upper end portion of the windward heat exchange pipe (13) is connected to the windward upper header portion (6), and the lower end portion thereof is connected to the windward lower header portion (11).

  Corrugated fins (16) made of an aluminum brazing sheet having a brazing filler metal layer on both sides are provided in the ventilation gap (15) of the heat exchange core (4) on both front and rear heat exchange tubes (13) of each tube assembly (14). It is arranged to straddle. Corrugated fins (16) are also arranged outside the tube assembly (14) of the heat exchange tubes (13) at the left and right ends, and the aluminum side plates (17) are arranged outside the corrugated fins (16) at the left and right ends. Is arranged and brazed to the corrugated fin (16). A ventilation gap (15) is also formed between the corrugated fins (16) at the left and right ends and the side plate (17).

  As shown in FIG. 2, in this embodiment, the entirety of the leeward upper header portion (5) is a refrigerant inflow section (18) through which refrigerant flows in through the refrigerant inlet (7). The entire upper upper header portion (6) is a refrigerant outflow section (not shown) through which the refrigerant flows out through the refrigerant outlet (8). In the refrigerant inflow section (18) of the leeward upper header section (5), in the refrigerant inflow section (18), the upper space (18a) where the refrigerant inlet (7) faces, and the lower space where the heat exchange pipe (13) faces A multi-hole sheet (19) made of a punching metal, a wire mesh, or a woven fabric is arranged so as to partition the space (18b). The multi-hole sheet (19) preferably has an opening of 0.05 to 2.5 mm and an opening ratio of 30 to 70%. In this case, when the refrigerant flowing into the refrigerant inflow section (18) from the refrigerant inlet (7) passes through the multi-hole sheet (19), relatively large bubbles contained in the refrigerant are effectively refined. And become fine bubbles, and the fine bubbles are effectively and uniformly dispersed in the liquid phase.

  Although not shown, the entire inside of the leeward side lower header portion (9) and the inside of the leeward side lower header portion (11) is one section, and both sections are connected by a passage in the communication member (12). It has been made.

  The evaporator (1) described above constitutes a refrigeration cycle together with a compressor, a condenser (refrigerant cooler) that cools refrigerant discharged from the compressor, an expansion valve (decompressor) that decompresses refrigerant that has passed through the condenser, and the like. Installed in automobiles as car air conditioners. When the compressor is in operation, the low-pressure gas-liquid mixed phase two-phase refrigerant compressed by the compressor and passed through the condenser and the expansion valve passes through the refrigerant inlet (7) and enters the evaporator (1). It enters the upper space (18a) in the refrigerant inflow section (18) of the leeward side upper header section (5), passes through the multi-hole sheet (19), and enters the lower space (18b). When the refrigerant passes through the multi-hole sheet (19), the gas phase contained therein is refined to become fine bubbles, and the fine bubbles are uniformly dispersed in the liquid phase. Therefore, the generation of slag flow in all the leeward heat exchange tubes (13) is suppressed, and the heat exchange efficiency is improved.

  The refrigerant that has entered the lower space (18b) of the refrigerant inflow section (18) flows downward in the heat exchange pipe (13) on the leeward side and enters the section of the leeward lower header section (9). (12) Enter the compartment in the upwind lower header portion (11) through the passage in. The refrigerant that has entered the section of the windward lower header section (11) flows upward in the heat exchange pipe (13) on the windward side and enters the refrigerant outflow section of the windward upper header section (6), and the refrigerant outlet Outflow from (8). Then, while the refrigerant flows in the heat exchange pipe (13), heat exchange is performed with the air passing through the ventilation gap (15), and the refrigerant flows out as a gas phase.

  The evaporator according to the present invention is suitably used in a refrigeration cycle constituting a car air conditioner of a vehicle.

(1): Evaporator
(2): Upper header tank
(3): Lower header tank
(5): Upper header on the leeward side
(6): Upwind header
(7): Refrigerant inlet
(9): Downward lower header
(11): Upwind lower header
(13): Heat exchange pipe
(18): Refrigerant inflow compartment
(18a): Upper space
(18b): Lower space
(19): Multi-hole sheet

Claims (3)

Arranged on the top and bottom sides of the heat exchange tubes, with multiple heat exchange tubes arranged in parallel at intervals with the longitudinal direction facing up and down, and with the longitudinal direction oriented in the direction of the heat exchange tubes And an evaporator having a pair of upper and lower header tanks having at least one header portion to which both ends of the heat exchange pipe are connected,
One header portion in the upper header tank is provided with a refrigerant inlet and a refrigerant inflow compartment into which the refrigerant flows through the refrigerant inlet, and the refrigerant inlet faces the refrigerant inflow compartment in the refrigerant inflow compartment. An evaporator in which a multi-hole sheet is arranged so as to partition into a space and a space where a heat exchange tube faces. A refrigerant inlet is provided at one end of the header portion in the longitudinal direction, and a refrigerant inflow section is provided at a portion of the header section in the longitudinal direction of the refrigerant inlet, and the refrigerant inflow section is partitioned into upper and lower spaces by a multi-hole sheet. The evaporator according to claim 1, wherein the refrigerant inlet faces the upper space of the refrigerant inflow compartment, and the heat exchange pipe faces the lower space of the refrigerant inflow compartment. The evaporator according to claim 1 or 2, wherein the multi-hole sheet is made of a punching metal, a wire mesh, or a woven fabric, and the multi-hole sheet has an opening of 0.05 to 2.5 mm and an opening ratio of 30 to 70%.

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