Capacitor

Abstract

Condenser having a condensation area and a subcooling area arranged such that the condensation area is positioned above the subcooling area, and which has a plurality of Heat exchange tubes arranged parallel to each other such that the heat exchange tubes are spaced apart from each other in a vertical direction and extend in a left / right direction; and has head tanks extending in the vertical direction, to which left and right end sections of the heat exchange tubes are connected, wherein three or more heat exchange paths, each formed by a plurality of heat exchange tubes arranged sequentially in the vertical direction, lying side by side in the vertical direction, two or more heat exchange paths are provided in the condensation area, Each of the heat exchange paths provided in the condensation area serves as a coolant condensation path for condensing coolant, the heat exchange path(s) that is / are provided in the subcooling area, serves / serves as a coolant subcooling path for subcooling coolant, a first head tank and a second head tank are provided at a left end section or right end section of the capacitor, the heat exchange tubes of the coolant subcooling path and the heat exchange tubes of the coolant condensation path of the lower end are connected to the first head tank, the heat exchanger tubes of the coolant condensation path (or paths), excluding the lower end coolant condensation path, are connected to the second head tank, the first head tank is located on the outside of the second head tank with respect to the left / right direction, an upper end of the first head tank is positioned above a lower end of the second head tank and a desiccant container containing a desiccant is arranged in the first head tank, wherein a branching flow control element is provided in the first head tank to be arranged on the inside with respect to the left / right direction, wherein the branching flow control element promotes a flow of the liquid phase coolant from the first head tank into the heat exchange tubes of the coolant subcooling path, which is adjacent to the coolant condensing path of the bottom end; the desiccant container is arranged in the first head tank to be positioned on the outside of the branching flow control element with respect to the left / right direction; a sealing section is provided for dividing an interior space of the first head tank into an upper and a lower space between a circumferential wall of the first head tank and the branching flow control element and a circumferential wall of the desiccant reservoir, whereby coolant that has flowed from the heat exchanger tubes of the coolant condensation path of the lower end into the first head tank flows into the desiccant reservoir into a region above the sealing section, from the desiccant reservoir flows into a region below the sealing section, and flows through the branching flow control element into the heat exchanger tubes of the coolant subcooling path that is adjacent to the coolant condensation path of the lower end; and A coolant influence area is provided immediately above the sealing section, wherein in this area the free space between the circumferential wall of the first head tank and the circumferential wall of the desiccant container is larger than that in an area above the coolant influence area, whereby coolant flows into the free space between the circumferential wall of the first head tank and the circumferential wall of the desiccant container above the coolant influence area and subsequently into the desiccant container.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a condenser suitable for use in, for example, a vehicle air conditioner, which is a cooling circuit provided in a vehicle.

[0002] Herein and in the appended claims, the top, bottom, left and right sides of the Fig. 1 are referred to as “top”, “bottom”, “left” and “right” respectively.

[0003] A condenser for a vehicle air conditioner is known (see, for example, Japanese Patent Application Laid-Open (kokai) No. 2001-33121). The known condenser has a condensing section and a subcooling section provided such that the former is located above the latter. The condenser includes a plurality of heat exchange tubes arranged in parallel such that their longitudinal direction coincides with the left / right direction and are spaced apart from each other in the vertical direction; fins each disposed between adjacent heat exchange tubes; and header tanks extending in the vertical direction and to which left and right end portions of the heat exchange tubes are connected, respectively. All heat exchange tubes have the same length.A heat exchange path formed by a plurality of heat exchange tubes arranged side by side in the vertical direction is provided in both the condensing section and the subcooling section. The heat exchange path provided in the condensing section serves as a refrigerant condensation path for condensing refrigerant, and the heat exchange path provided in the subcooling section serves as a refrigerant subcooling path for subcooling the refrigerant. Heat tanks, to which all the heat exchange tubes are connected, are provided at the left and right ends of the condenser. The interior of each of the two header tanks is divided into upper and lower header sections by a partition provided at a vertical position between the refrigerant condensation path and the refrigerant subcooling path.The left and right end portions of the heat exchange tubes of the refrigerant condensation path are connected to the upper header portions of the two header tanks, and the left and right end portions of the heat exchange tubes of the refrigerant subcooling path are connected to the lower header portions of the two header tanks. A refrigerant inlet is provided at the upper header portion of one header tank, and a refrigerant outlet is provided at the lower header portion of the header tank. A liquid receiver, which separates gas and liquid and stores the liquid, is connected to the other header tank, and communication is established between the interior of the liquid receiver and the interiors of the upper and lower header portions of the other header tank.During operation, refrigerant flows from the upper header of the other header tank into the liquid receiver, and the gas and liquid portions of the refrigerant are separated from each other in the liquid receiver. The liquid portion, i.e., the predominant liquid phase of the mixed refrigerant, then flows into the lower header of the other header tank.

[0004] However, in the condenser disclosed in the above-mentioned publication, all heat exchange tubes have the same length; the interior of each of the two header tanks is divided into upper and lower header regions by a partition provided at a vertical position between the refrigerant condensing path and the refrigerant subcooling path; and the left and right end portions of the heat exchange tubes of the refrigerant condensing path are connected to the upper header regions of the two heat tanks. Thus, the condensing region and the subcooling region have the same length measured along the left / right direction.Consequently, in the case where the dimensions of the condenser including the liquid receiver measured along the vertical direction and the left / right direction are fixed to a certain dimension, the areas of the heat exchange sections of the condensing region and the subcooling region become insufficient, and further improvement of the refrigerant condensing efficiency and the refrigerant subcooling efficiency cannot be obtained.

[0005] In view of the above, the present applicant has proposed a condenser for a vehicle air conditioner in which the refrigerant condensing efficiency and the refrigerant subcooling efficiency are further improved (see WO 2010 / 047320). The proposed condenser has a condensing section and a subcooling section provided such that the former is located above the latter. The condenser includes a plurality of heat exchange tubes arranged in parallel so as to be spaced apart from each other in a vertical direction and extending in the left / right direction; and header tanks extending in the vertical direction, to which left and right end portions of the heat exchange tubes are connected, respectively.Three or more heat exchange paths, each formed by a plurality of heat exchange tubes arranged sequentially in the vertical direction, are provided so that the heat exchange paths are adjacent to each other in the vertical direction. The heat exchange paths provided in the condensing section serve as refrigerant condensation paths for condensing the refrigerant, and the heat exchange path provided in the subcooling section serves as a refrigerant subcooling path for subcooling the refrigerant. A first header tank and a second header tank are provided at the left end or right end of the condenser. The heat exchange tubes of the refrigerant subcooling path and the heat exchange tubes of the refrigerant condensing path at the lower end are connected to the first header tank.The heat exchange tubes of the coolant subcooling paths, excluding the lower end of the coolant condensation path, are connected to the second header tank. The first header tank is arranged on an outer side of the second header tank with respect to the left / right direction, and the upper end of the first header tank is provided above the lower end of the second header tank. A desiccant container accommodating a desiccant is provided within the first header tank.

[0006] According to the condenser disclosed in WO 2010 / 047320, in the case where the dimensions of the condenser measured along the vertical direction and the left / right direction are equal to those (including the dimensions of the liquid receiver) of the condenser disclosed in Japanese Patent Application Publication No. 2001-33121, the length of the heat exchange tubes of the lower-end refrigerant condensation path can be made longer than the length of the heat exchange tubes of the refrigerant condensation path of the condenser disclosed in Japanese Patent Application Publication No. 2001-33121. Thus, the area of ​​the heat exchange portion of the condensation region increases.Furthermore, since the length of the heat exchange tubes of the refrigerant subcooling path can be made longer than the length of the heat exchange tubes of the refrigerant subcooling path of the condenser disclosed in Japanese Patent Application Publication No. 2001-33121, the area of ​​the heat exchange section of the subcooling region increases. As a result, the refrigerant condensation efficiency and the refrigerant subcooling efficiency can be further improved.

[0007] Furthermore, the condenser disclosed in WO 2010 / 047320 must meet the following conditions. First, when supplying refrigerant to a refrigeration cycle, the amount of refrigerant supplied to the refrigeration cycle must be increased at an early stage to an appropriate level at which the degree of subcooling becomes constant. Second, a stable range in which the degree of subcooling becomes constant must be broadened to obtain a subcooling characteristic that is more stable against load fluctuations and / or refrigerant leakage. Furthermore, it is necessary to bring the entire refrigerant into contact with a desiccant to efficiently remove moisture from the refrigerant. SUMMARY OF THE INVENTION

[0008] An object of the present invention is to provide a condenser that meets the above-mentioned requirements; that is, a condenser in which the amount of refrigerant supplied to a refrigeration cycle can be increased to a suitable level at an early stage, and in which moisture can be efficiently removed from the refrigerant.

[0009] In order to achieve the above object, the invention has the following forms. (1) A condenser having a condensing section and a subcooling section provided such that the condensing section is provided above the subcooling section, and including a plurality of heat exchange tubes arranged in parallel such that the heat exchange tubes are spaced apart from each other in a vertical direction and extend vertically in a left / right direction; and header tanks extending in the vertical direction and to which left and right end portions of heat exchange tubes are connected, wherein three or more heat exchange paths each formed by a plurality of heat exchange tubes arranged sequentially in the vertical direction are adjacent to each other in the vertical direction, two or more heat exchange paths are provided in the condensing section, wherein each of the heat exchange paths provided in the condensing sectionserves as a coolant condensation path for condensing the coolant, the heat exchange path(s) provided in the subcooling region serves as a coolant subcooling path for subcooling the coolant, a first header tank and a second header tank are provided at a left end portion or right end portion of the condenser, the heat exchange tubes of the coolant subcooling path and the heat exchange tubes of the lower-end coolant condensation path are connected to the first header tank, the heat exchange tubes of the coolant condensation path(s), excluding the lower-end coolant condensation path, are connected to the second header tank, the first header tank is arranged on the outside of the second header tank with respect to the left / right direction,an upper end of the first head tank is arranged above a lower end of the second head tank and a coolant container containing a coolant is arranged in the first head tank, wherein, a branch flow control member is provided in the first header tank to be arranged on the inside with respect to the left / right direction, the branch flow control member promoting a liquid phase refrigerant flow from the first header tank into the heat exchange tubes of the refrigerant subcooling path adjacent to the lower end refrigerant condensing path; the desiccant container is arranged in the first head tank to be located on the outside of the branch flow control member with respect to the left / right direction; a sealing portion for dividing an interior space of the first header tank into upper and lower spaces is provided between a peripheral wall of the first header tank and the branch flow control member and a peripheral wall of the desiccant container, whereby refrigerant that has flowed into the first header tank flows from the heat exchange tubes of the lower-end refrigerant condensation path into the desiccant container in a region above the sealing portion, flows from the desiccant container in a region below the sealing portion, and flows through the branch flow control member into the heat exchange tubes of the refrigerant subcooling path adjacent to the lower-end refrigerant condensation path; and a coolant inflow region is provided immediately above the sealing region, wherein in the region the clearance between the peripheral wall of the first heat tank and the peripheral wall of the desiccant container is larger than that in a region above the coolant inflow region, whereby coolant flows into the clearance between the peripheral wall of the first head tank and the peripheral wall of the desiccant container above the coolant influence area into the coolant influence area and then flows into the desiccant container. (2) The condenser according to paragraph (1), wherein a lower end of the branch flow control member is disposed below the heat exchange tube of the lower end of the refrigerant subcooling path provided adjacent to the lower end refrigerant condensing path; an upper end of the branch flow control member is disposed above the heat exchange tube of the upper end of the refrigerant subcooling path provided adjacent to the lower end refrigerant condensing path; at least a portion of the desiccant container is disposed within a vertical range over which the branch flow control member extends in the vertical direction; and the sealing portion is provided within the vertical range of the branch flow control member. (3) The condenser according to paragraph (2), wherein a refrigerant subcooling path is provided in the subcooling region; the branch flow control member is provided at a vertical position corresponding to the refrigerant subcooling path; the branch flow control member is provided in the first header tank in such a manner as to form a closed refrigerant inflow space that communicates with the heat exchange tubes of the refrigerant subcooling path and allows the refrigerant to flow into the heat exchange tubes of the refrigerant subcooling path; and a communication port is provided at a lower end portion of the branch flow control member so that communication is established between the lower space of the first header tank, which is located below the sealing portion, and the refrigerant inflow space. (4) The condenser according to paragraph (3), wherein the branch flow control element includes a partition wall oriented so that its longitudinal direction coincides with the vertical direction and which divides the internal space of the first header tank into an inner space and an outer space with respect to the left / right direction, and upper and lower closing walls provided at upper and lower ends of the partition wall for closing the upper and lower end openings of the internal space located on the inner side of the partition wall with respect to the left / right direction; the partition wall and the upper and lower closing walls form the refrigerant inflow space; and the communication port is formed in the partition wall or the lower closing wall. (5) The condenser according to paragraph (3) or (4), wherein the refrigerant inflow portion is provided by forming a recess on the peripheral wall of the desiccant tank; a first inflow port is formed in the peripheral wall of the desiccant tank at a position above the recess so that the refrigerant flowing from the heat exchange tubes of the lower-end refrigerant condensing path into the first header tank flows into the desiccant tank via the first inflow port; a second inflow port is formed in the peripheral wall of the desiccant tank at a position corresponding to the recess so that the refrigerant introduced into the recess flows into the desiccant tank via the second inflow port;and an outflow opening is formed in the peripheral wall of the desiccant container in a region below the sealing portion so that refrigerant flows from the space inside the desiccant container through the outflow opening into the space inside the first header tank; (6) The condenser according to paragraph (1), wherein the first header tank is constructed of a tubular main body having a closed upper end and an open lower end, and a lower closure member attached to the lower end of the tubular main body so as to be capable of closing the opening of the lower end of the tubular main body; a lower end of the desiccant container is disposed below a lower end of the branch flow control member; and rattling noise preventing means is provided on the desiccant container at a position below the branch flow control member, the rattling noise preventing means extending between the branch flow control member and the lower closure member of the first header tank to thereby prevent rattling noise of the desiccant container. (7) The condenser according to paragraph (6), wherein the rattling noise preventing means is press-fitted from the upper side by means of the branch flow control member and is press-fitted from the lower side by means of the lower closure member of the first header tank, whereby the rattling noise preventing means is elastically deformed; and rattling noise of the desiccant container is prevented by means of the elastic restoring force of the rattling noise preventing means. (8) The condenser according to paragraph (7), wherein the rattling noise preventing means comprises an upper rattling noise preventing arm provided on the desiccant container and having a distal end portion in contact with the lower end portion of the branch flow control member from the lower side thereof, and a lower rattling noise preventing arm provided on the desiccant container and having a distal end portion in contact with the lower closure member from the upper side thereof. EFFECT OF THE INVENTION

[0010] According to the condensers of paragraphs 1) to 8), a branch flow control element for promoting the flow of the liquid phase of the refrigerant from the first header tank into the heat exchange tubes of the refrigerant subcooling path provided adjacent to the lower-end refrigerant condensing path is provided in the first header tank to be arranged on the inside with respect to the left / right direction. Consequently, when the refrigerant is introduced into the refrigeration cycle, the liquid phase of the refrigerant quickly flows from the first header tank into the heat exchange tubes constituting the refrigerant subcooling path.Consequently, the interiors of the heat exchange tubes of the coolant subcooling path can be rapidly filled with liquid-phase coolant at an early stage, allowing the amount of coolant introduced into the refrigeration cycle to be increased at an early stage to an appropriate level at which the degree of subcooling becomes constant. Furthermore, since the width of the stable range in which the degree of subcooling becomes constant, that is, the range of the amount of coolant supplied in which the degree of subcooling becomes constant, becomes larger, a subcooling characteristic more stable against load fluctuations and / or coolant leakage can be obtained.

[0011] Furthermore, the desiccant container is arranged in the first header tank to be provided on the outside of the branch flow control member with respect to the left / right direction; and the sealing portion for dividing the interior of the first header tank into upper and lower spaces is provided between a peripheral wall of the first header tank and the branch flow control member and a peripheral wall of the desiccant container. Thus, refrigerant that has flowed from the heat exchange tubes of the lower-end refrigerant condensation path into the first header tank flows into the desiccant container, into a region above the sealing portion, flows out from the desiccant container into a region below the sealing portion, and flows through the branch flow control member into the heat exchange tubes of the refrigerant subcooling path provided adjacent to the lower-end refrigerant condensation path.Consequently, the entire coolant can be brought into contact with the desiccant, which allows moisture to be efficiently removed from the coolant.

[0012] Furthermore, a coolant inflow region is provided immediately above the sealing portion, which divides the interior of the first header tank into an upper and a lower space. In the coolant inflow region, the clearance between the peripheral wall of the first header tank and the peripheral wall of the desiccant container is larger than that in a region above the coolant inflow region. Thus, coolant in the clearance between the peripheral wall of the first header tank and the peripheral wall of the desiccant container above the coolant inflow region flows into the coolant inflow region and then flows into the desiccant container. Consequently, the following effect is obtained.In the case where the desiccant container is disposed within the first header tank to be located on the outside of the branch flow control element with respect to the left / right direction, the clearance between the peripheral wall of the first header tank and the peripheral wall of the desiccant container inevitably becomes small. Consequently, refrigerant flowing from the heat exchange tubes of the lower-end refrigerant condensation path into the first header tank and lubricating oil for a compressor contained in the refrigerant may stagnate in the clearance. As a result, the lubricating oil of the compressor cannot be quickly returned to the compressor, and lubrication within the compressor becomes insufficient, which may adversely affect the compressor's durability and shorten the compressor's service life.However, in the case where the condenser has a refrigerant inflow portion provided immediately above the sealing portion and into which refrigerant flows from the clearance between the peripheral wall of the first header tank and the peripheral wall of the desiccant tank, and which is configured so that the refrigerant that has flowed into the refrigerant inflow portion flows into the desiccant tank, the refrigerant stagnating in the clearance and containing the lubricating oil of the compressor flows into the refrigerant inflow portion as if it were guided into the refrigerant inflow portion, and flows into the desiccant tank via the refrigerant inflow portion.Consequently, the refrigerant containing the compressor lubricating oil flows out from the desiccant tank to a region below the seal portion, along with the remaining refrigerant that has flowed into the desiccant tank, and flows through the branch flow control element into the heat exchange tubes of the refrigerant subcooling path adjacent to the lower-end refrigerant condensing path. Consequently, it becomes possible to quickly return the compressor lubricating oil to the compressor, thereby solving the above-mentioned problems.

[0013] According to the condenser according to paragraph 2), a lower end of the branch flow control member is arranged below the heat exchange tube of the lower end of the refrigerant subcooling path adjacent to the lower end refrigerant condensing path; an upper end of the branch flow control member is arranged above the heat exchange tube of the upper end of the refrigerant subcooling path adjacent to the lower end refrigerant condensing path; at least a portion of the desiccant container is arranged within a vertical range over which the branch flow control member extends in the vertical direction; and the sealing portion is provided within the vertical range of the branch flow control member.Consequently, the refrigerant that has flowed from the heat exchange tubes of the lower-end refrigerant condensing path into the first header tank easily flows into the desiccant container, into a region above the sealing portion, flows out of the desiccant container into a region below the sealing portion, and flows through the branch flow control member into the heat exchange tubes of the refrigerant subcooling path adjacent to the lower-end refrigerant condensing path.

[0014] According to the capacitors of paragraphs 3) and 4), the structure of the branch flow control element can be made relatively simple.

[0015] According to the condenser of paragraph 5), the structure for allowing the refrigerant that has flowed from the heat exchange tubes of the lower-end refrigerant condensing path into the first header tank to flow into the desiccant tank in a region above the sealing portion, to flow out from the desiccant tank in a region below the sealing portion, and to flow through the branch flow control member into the heat exchange tubes of the refrigerant subcooling path adjacent to the lower-end refrigerant condensing path; the structure of the refrigerant influencing portion; and the structure for allowing the refrigerant that has been guided into the refrigerant influencing portion to flow into the desiccant tank can be provided relatively easily.

[0016] According to the condensers of paragraphs 6) to 8), the first header tank is constructed of a tubular main body having a closed upper end and an open lower end, and a lower closure member detachably attached to the lower end of the tubular main body to close the lower end opening of the tubular main body; a lower end of the desiccant container is disposed below a lower end of the branch flow control member; and rattling noise preventing means is provided on the desiccant container at a position below the branch flow control member, the rattling noise preventing means extending between the branch flow control member and the lower closure member of the first header tank, thereby preventing rattling noise of the refrigerant container.As a result, even when vibrations are applied to the condenser, rattling noise from the desiccant container can be avoided. Consequently, it is possible to prevent the generation of noise and breakage of the desiccant container, which would otherwise occur due to rattling noise from the desiccant container.

[0017] According to the condenser according to paragraph 7), since the vibrations acting on the condenser are absorbed by the elastically deformed rattling noise prevention means, rattling noise of the desiccant container can be effectively prevented.

[0018] According to the condenser of paragraph 8), the means for preventing rattling noise can be provided relatively easily between the branch flow control member and the lower closure member of the first head tank. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view specifically showing the overall structure of the capacitor according to the present invention; Fig. Fig. 2 is a vertical sectional view with omissions showing a lower portion of a first head tank of the condenser shown in Fig. 1, on an enlarged scale; Fig. 3 is a sectional view taken along the line AA of the Fig. 2 is taken; Fig. 4 is a sectional view taken along the line BB of the Fig. 2 is taken; and Fig. Fig. 5 is a perspective exploded view showing a lower portion of the first head tank of the condenser shown in Fig. 1, on an enlarged scale. DESCRIPTION OF THE PREFERRED EMBODIMENT

[0019] An embodiment of the present invention will be described below with reference to the drawings.

[0020] In the following description, the reverse side of the sheet on which the Fig. 1 (the upper side in the Fig. 3 and Fig. 4) is called “front” and the opposite side is called “back”.

[0021] Furthermore, the term “aluminium” as used in the following description includes aluminium alloys in addition to pure aluminium.

[0022] Fig. 1 specifically shows the overall structure of a capacitor according to the present invention; and the Fig. 2 to 5 show the structure of a main section of the capacitor of the Fig. 1.

[0023] In Fig. 1, a condenser 1 includes a plurality of flat heat exchange tubes 2A, 2B formed of aluminum, three header tanks 3, 4, 5 formed of aluminum, corrugated fins 6A, 6B formed of aluminum, and side plates 7 formed of aluminum. The heat exchange tubes 2A, 2B are arranged such that their width direction coincides with a front-and-back direction, their length direction coincides with a left-and-right direction, and they are spaced apart from each other in a vertical direction. Left and right end portions of the heat exchange tubes 2A, 2B are connected by brazing to the header tanks 3, 4, 5 extending in the vertical direction.Each of the corrugated fins 6A, 6B is arranged between adjacent heat exchange tubes 2A, 2B and brazed to them, or is arranged on the outer side of the uppermost or lowermost heat exchange tubes 2A, 2B and brazed to the corresponding heat exchange tube 2A, 2B. The side plates 7 are arranged on the corresponding outer sides of the uppermost and lowermost corrugated fins 6A, 6B and brazed to these corrugated fins 6A, 6B. The condenser 1 has a condensing section 1A and a subcooling section 1B arranged so that the former is located above the latter.

[0024] In the condenser 1, three or more heat exchange paths (in the present embodiment, three heat exchange paths P1, P2, P3), each formed with a plurality of heat exchange tubes 2A, 2B arranged sequentially in the vertical direction, are adjacent to each other in the vertical direction. The three heat exchange paths are referred to as first to third heat exchange paths P1, P2, P3 from the top. The flow direction of the refrigerant is the same among all the heat exchange tubes 2A, 2B forming the corresponding heat exchange path P1, P2, P3. The flow direction of the refrigerant in the heat exchange tubes 2A, 2B forming a particular heat exchange path is opposite to the flow direction of the refrigerant in the heat exchange tubes 2A, 2B forming another heat exchange path adjacent to the particular heat exchange path.The first and second heat exchange paths P1, P2 are provided in the condensation region 1A and serve as refrigerant condensation paths. The third heat exchange path P3 is provided in the subcooling region 1B and serves as the refrigerant subcooling path.

[0025] A first header tank 3 and a second header tank 4 are individually provided at the left end of the condenser 1. The heat exchange tubes 2A constituting the refrigerant subcooling path (i.e., the third heat exchange paths P3) and the refrigerant condensation path at the lower end (i.e., the second heat exchange paths P2) are connected to the first header tank 3 by brazing. The heat exchange tubes 2B of the remaining refrigerant condensation path (i.e., the first heat exchange paths P1) are connected to the second header tank 4 by brazing. Herein, the heat exchange tubes 2A connected to the first header tank 3 are referred to as first heat exchange tubes, and the heat exchange tubes 2B connected to the second header tank 4 are referred to as second heat exchange tubes.The corrugated fins 6A arranged between the adjacent first heat exchange tubes 2A and those between the lower-end first heat exchange tube 2A and the lower side plate 7 are referred to as first corrugated fins. The corrugated fins 6B arranged between the adjacent second heat exchange tubes 2B, those between the upper-end second heat exchange tube 2B and the upper side plate 7, and those between the lower-end second heat exchange tube 2B and the upper-end first heat exchange tube 2A are referred to as second corrugated fins.

[0026] The first header tank 3 is formed by a tubular main body 8 made of aluminum and a lower closure member 9. The tubular main body 8 is composed of a tubular peripheral wall 8a whose opposite ends are open, and an upper wall 8b that is brazed to an upper end portion of the peripheral wall 8a and closes the upper end opening of the peripheral wall 8a. Thus, the tubular main body 8 is closed at its upper end and open at its lower end. The lower closure member 9 is detachably attached to a lower end portion of the tubular main body 8 and closes the lower end opening of the tubular body 8. The first header tank 3 is arranged on the left side (on the outside with respect to the left / right direction) of the second header tank 4.The upper end of the first head tank 3 is arranged above the lower end of the second head tank 4, and the lower end of the first head tank 3 is arranged below the lower side plate 7.

[0027] The first header tank 3 serves as a liquid receiver that separates gas and liquid by utilizing gravity and stores the separated liquid. That is, the internal volume of the first header tank 3 is determined so that a portion of the gas / liquid phase of the mixed refrigerant that has flowed into the first header tank 3, i.e., the predominant liquid phase of the mixed refrigerant, accumulates in a lower region within the first header tank 3 due to gravity, and the gas phase component of the gas / liquid phase of the mixed refrigerant accumulates in an upper region within the first header tank 3 due to gravity, whereby the predominant liquid phase of the mixed refrigerant flows into the first heat exchange tubes 2A of the third heat exchange path P3.

[0028] The third header tank 5 is located at the right end of the condenser 1, and all the heat exchange tubes 2A, 2B constituting the first to third heat exchange paths P1-P3 are connected to the third header tank 5. The interior of the third header tank 5 is divided into an upper header region 12 and a lower header region 13 by an aluminum partition plate 11 provided at a vertical portion between the second heat exchange path P2 and the third heat exchange path P3. Left end portions of the second heat exchange tubes 2B of the first heat exchange path P1 are connected to the second header tank 4, and right end portions thereof are connected to the upper header region 12 of the third header tank 5. Left end portions of the first heat exchange tubes 2A of the second heat exchange path P2 are connected to the first header tank 3, and right end portions thereof are connected to the upper header region 12 of the third header tank 5.Left end portions of the first heat exchange tubes 2A of the third heat exchange path P3 are connected to the first header tank 3, and right end portions thereof are connected to the lower header portion 13 of the third header tank 5.

[0029] The second header tank 4, a portion of the first header tank 3 to which the first heat exchange tubes 2A of the second heat exchange path P2 are connected, the upper header region 12 of the third header tank 5, and the first and second heat exchange paths P1, P2 form the condensing region 1A that condenses refrigerant. A portion of the first header tank 3 to which the first heat exchange tubes 2A of the third heat exchange path P3 are connected, the lower header region 13 of the third header tank 5, and the third heat exchange path P3 form the subcooling region 1B that subcools the refrigerant. Each of the first and second heat exchange paths P1, P2 serves as a refrigerant condensing path for condensing refrigerant, and the third heat exchange path P3 serves as a refrigerant subcooling path for subcooling refrigerant.

[0030] A coolant inlet (not shown) is formed at a portion of the second header tank 4 partially forming the condensing region 1A, the portion protruding upward from the upper end of the first header tank 3, and a coolant outlet (not shown) is formed at the lower header portion 13 of the third header tank 5 partially forming the subcooling region 1B. A coolant inlet member 14 communicating with the coolant inlet is connected to the second header tank 4, and a coolant outlet member 15 communicating with the coolant outlet is connected to the third header tank 5.

[0031] As it is in the Fig.2 to 5, at a portion of the first header tank 3 whose portion protrudes downward from the lower side plate 7, an internal thread 16 is formed on the inner peripheral surface of a lower end portion of the peripheral wall 8a of the tubular main body 8. Further, the lower closure member 9 has an insertion portion 9a inserted into the tubular main body 8 and an external thread 17 formed on the outer peripheral surface of the insertion portion 9a. As a result of the external thread 17 of the insertion portion 9a being screwed to the internal thread 16 of the peripheral wall 8a, the lower closure member 9 is detachably attached to the lower end portion of the tubular main body 8.Furthermore, sealing rings 18, 19 attached to the insertion portion 9a of the lower closure member 9 provide a seal between portions of the outer peripheral surface of the insertion portion 9a provided on the upper and lower sides of the external thread 17 and portions of the inner peripheral surface of the peripheral wall 8a provided on the upper and lower sides of the internal thread 16.

[0032] A branch flow control member 21 for promoting the flow of the liquid-phase refrigerant from the first header tank 3 into the first heat exchange tubes 2A of the third heat exchange path P3 is provided in the first header tank 3 so that the branch flow control member 21 is arranged on the right side (the inside in the left / right direction). A desiccant container 22 containing a desiccant D is arranged in the first header tank 3 so as to be arranged on the left side (the outside in the left / right direction) of the branch flow control member 21. A sealing portion 23 for dividing the interior of the first header tank 3 into upper and lower spaces is provided between the inner surface of the peripheral wall 8a of the tubular main body 8 of the first header tank 3 and the branch flow control member 21, and the outer surface of the peripheral wall of the desiccant container 22.Thus, the refrigerant that has flowed from the first heat exchange tubes 2A of the second heat exchange path P2, which is the lower-end refrigerant condensation path, into the first header tank 3 flows into the desiccant container 22, in a region above the sealing portion 23, and flows out of the desiccant container 22 from a region below the sealing portion 23. The refrigerant then flows through the branch flow control member 21 into the first heat exchange tubes 2A of the refrigerant subcooling path adjacent to the lower-end refrigerant condensation path.

[0033] The branch flow control member 21 is provided at a vertical position corresponding to the third heat exchange path P3, which is the coolant subcooling path, such that the lower end of the branch flow control member 21 is located below the first heat exchange tube of the lower end 2A of the third heat exchange path P3, and the upper end of the branch flow control member 21 is located between the first heat exchange tube of the upper end 2A of the third heat exchange path P3 and the first heat exchange tube of the lower end 2A of the second heat exchange path P2. The branch flow control member 21 forms a closed coolant inflow space 24 that communicates with the first heat exchange tubes 2A of the third heat exchange path P3 and causes the coolant to flow into the first heat exchange tubes 2A of the third heat exchange path P3.It should be noted that a portion of the interior of the first head tank 3 positioned above the sealing portion 23 excluding the coolant inflow space 24 is referred to as a first space 25, and a portion of the interior of the first head tank 3 positioned below the sealing portion 23 excluding the coolant inflow space 24 is referred to as a second space 26.

[0034] The branch flow control member 21 includes a rectangular partition wall 27 and upper and lower closure walls 28, 29 having a semicircular shape when viewed from above. The partition wall 27 is oriented so that its longitudinal direction coincides with the vertical direction and its width direction coincides with the front-and-back direction. The partition wall 27 divides the interior space of the first header tank 3 into inner and outer sections with respect to the left-right direction. The upper and lower closure walls 28, 29 are provided at the upper and lower ends of the partition wall 27, respectively, and close the upper and lower end openings of the space located on the inner side of the partition wall 27 with respect to the left-right direction.Front and rear edge portions of the partition wall 27 are brazed to the peripheral wall 8a of the tubular main body 8 of the first header tank 3 at positions positioned outward (in the front-to-back direction) with respect to the tube insertion holes 31 formed in the peripheral wall 8a, which are elongated in the front-to-back direction and into which the left end portions of the first heat exchange tubes 2A are inserted. Projections 28a, 29a, which are to be fitted into through holes 32 formed in the peripheral wall 8a of the tubular main body 8 of the first header tank 3, are formed at the distal end of the upper and lower closure walls 28, 29. In a state where the projections 28a, 29a are fitted into the through holes 32, bent peripheral edge portions of the upper and lower closure walls 28, 29 and the projections 28a, 29a are soldered to the peripheral wall 8a.The partition wall 27 and the upper and lower closure walls 28, 29 of the branch flow control element 21 form the coolant inflow space 24. The lower closure wall 29 of the branch flow control element 21 has a communication opening 33 which establishes communication between the second space 26 of the first head tank 3 and the coolant inflow space 24.

[0035] The desiccant container 22 is made of plastic and is composed of a bottom-closed tubular main body 34 whose upper end is open and whose lower end is closed, and an upper closure member 35 detachably attached to the upper end of the bottom-closed tubular main body 34 to close the upper end opening of the bottom-closed tubular main body 34. The upper end of the desiccant container 22 is located in the vicinity of the upper end of the first header tank 3, and the lower end thereof is located slightly below the lower end of the branch flow control member 21. A lower portion of the desiccant container 22, which has a certain length, is arranged in a vertical region over which the branch flow control member 21 extends in the vertical direction.The peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant tank 22 has a semicircular transverse cross-section and includes a flat strip-shaped portion 37 parallel to the front-and-back direction and a semi-cylindrical portion 38 whose front and rear edges are continuous with the front and rear edges of the strip-shaped portion 37. A portion of the strip-shaped portion 37 of the bottom-closed tubular main body 34 of the refrigerant tank 22 located below a central portion of the branch flow control member 21 with respect to the vertical direction is narrower than the remaining portion of the strip-shaped portion 37 located above this portion. This narrow portion is designated 37a, and the wide portion above the narrow portion is designated 37b.Note that the right side surface of a portion of the narrow portion 37a located below the sealing portion 23 is slightly recessed. A portion of the semi-cylindrical portion 38 of the bottom-closed tubular main body 34 of the desiccant container 22 located below the central portion of the branch flow control member 21 in the vertical direction is narrower in diameter than the remaining portion above the portion. This narrow diameter portion is designated 38a, and the large diameter portion above the small diameter portion is designated 38b.

[0036] The sealing portion 23 is integrally provided so as to protrude outward from a central portion (with respect to the vertical direction) of the small diameter portion 38a of the semi-cylindrical portion 38 of the bottom-closed tubular main body 34 of the desiccant container 22. The distal end of the sealing portion 23 contacts a portion of the inner peripheral surface of the peripheral wall 8a of the tubular main body 8 of the first header tank 3, which portion is positioned on the left side of the branch flow control member 21. A portion of the outer surface of the small diameter portion 38a positioned above the sealing portion 23 forms a recess 39 on the left side of the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22.This recess 39 forms a coolant inflow region 41 immediately above the sealing portion 23. In the coolant inflow region 41, the clearance between the peripheral wall 8a of the tubular main body 8 of the first header tank 3 and the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22 is larger than that in the clearance above the coolant inflow region 41. The coolant flows into the coolant inflow region 41 from the clearance between the peripheral wall 8a of the tubular main body 8 of the first header tank 3 and the large diameter portion 38b of the semi-cylindrical portion 38 of the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22.

[0037] A plurality of first inflow holes 42 are formed in the wide portion 37b of the strip-shaped portion 37 of the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22 and the large-diameter portion 38b of the semi-cylindrical portion 38 thereof. Thus, the refrigerant that has flowed from the first heat exchange tubes 2A of the second heat exchange path P2 into the first space 25 of the first header tank 3 flows into the desiccant container 22 via the first inflow holes 42. A plurality of second inflow holes 43 are formed in the small-diameter portion 38a of the semi-cylindrical portion 38 of the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22.Thus, the coolant introduced into the coolant inflow region 41 flows through the second inflow openings 43 into the desiccant container 22. Furthermore, outflow openings 44 are formed in the narrow portion 37a of the strip-shaped portion 37 of the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22 and the small-diameter portion 38a of the semi-cylindrical portion 38 thereof. Thus, the coolant flows from the desiccant container 22 through the outflow openings 44 into the second space 26 of the first header tank 3. The inflow openings 42, 43 and the outflow openings 44 are covered with a fine filter or mesh filter 46.

[0038] An upper rattle-eliminating arm 47 and a lower rattle-eliminating arm 48 are integrally provided at a lower end portion of the strip-shaped portion 37 of the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22. The upper rattle-eliminating arm 47 protrudes to the right, and its distal end portion contacts the lower end of the lower closure wall 29 of the branch flow control member 21. The lower rattle-eliminating arm 48 protrudes to the right and is inclined downward, and its distal end portion contacts the upper surface of the insertion portion 9a of the lower closure member 9.At least one of the two rattle-eliminating arms is elastically deformed, and its elastic restoring force causes the upper and lower rattle-eliminating arms 47, 48 to expand between the lower closure wall 29 of the branch flow control member 21 and the insertion portion 9a of the lower closure member 9. Thus, vibrations acting on the condenser 1 are absorbed, and rattle noises of the desiccant container 22 are prevented. Furthermore, a handle or knob 49, which is used for inserting the desiccant container 22 into the first header tank 3 and removing the desiccant container 22 from the first header tank 3, is provided on the lower surface of the bottom wall of the bottom-closed tubular main body 34 of the desiccant container 22.

[0039] The condenser 1 forms a refrigerant circuit together with a compressor, an expansion valve (pressure reducer) and an evaporator; and the refrigerant circuit is provided in a vehicle as a vehicle air conditioner.

[0040] In the condenser 1 having the above-described structure, high-temperature and high-pressure gas-phase refrigerant compressed by the compressor flows into the second header tank 4 via the refrigerant inlet member 14 and the refrigerant inlet. The gas-phase refrigerant is condensed while flowing rightward within the second heat exchange tubes 2B of the first heat exchange path P1 and flows into the upper header portion 12 of the third header tank 5. The refrigerant that has flowed into the upper header portion 12 of the third header tank 5 is condensed while flowing leftward within the first heat exchange tubes 2A of the second heat exchange path P2 and flows into the first space 25 of the first header tank 3.

[0041] The refrigerant that has flowed into the first space 25 of the first header tank 3 is a mixed gas / liquid phase refrigerant. A portion of the mixed gas / liquid phase refrigerant, that is, the predominant liquid phase of the mixed refrigerant, flows downward due to gravity. The gas phase component of the mixed gas / liquid phase refrigerant that has flowed into the first space 25 remains in an upper region of the first space 25 of the first header tank 3. Specifically, the mixed gas / liquid phase refrigerant that has flowed into the first space 25 enters the desiccant tank 22 via the first inlet ports 42 of the desiccant tank 22 and is subsequently separated into gas and liquid (predominant liquid phase of the mixed refrigerant).Alternatively, the mixed gas / liquid phase refrigerant is separated into gas and liquid (predominant liquid phase of the mixed refrigerant) before entering the desiccant container 22, and the mixed gas / liquid phase refrigerant enters the desiccant container 22 via the first inlet ports 42. Within the desiccant container 22, the predominant liquid phase of the mixed refrigerant comes into contact with the desiccant D, thereby removing moisture from the refrigerant.

[0042] Furthermore, the predominant liquid phase of the mixed refrigerant present in the clearance between the peripheral wall 8a of the tubular main body 8 of the first header tank 3 and the semi-cylindrical portion 38 of the peripheral wall 36 of the bottom-closed tubular main body 34 of the desiccant container 22 flows into the refrigerant inflow area 41 as if it had been introduced into the refrigerant inflow area 41 and enters the desiccant container 22 via the second inflow openings 43. Thus, the predominant liquid phase of the mixed refrigerant comes into contact with the desiccant D, and moisture is removed from the refrigerant.

[0043] The predominant liquid phase of the mixed refrigerant that has entered the desiccant tank 22 flows downward within the desiccant tank 22 and flows into the second space 26 via the outflow ports 44. The predominant liquid phase of the mixed refrigerant then flows through the communication port 33 of the branch flow control member 21 and enters the refrigerant inflow space 24. The predominant liquid phase of the mixed refrigerant that has entered the refrigerant inflow space 24 flows into the first heat exchange tubes 2A of the third heat exchange path P3 and is subcooled while flowing rightward within the first heat exchange tubes 2A of the third heat exchange path P3. Thereafter, the subcooled refrigerant enters the lower header portion 13 of the third header tank 5 and flows out via the refrigerant outlet and the refrigerant outlet member 15.The coolant is then fed to the evaporator via the expansion valve.

[0044] When refrigerant is introduced into the vehicle air conditioner described above, since the pressure in the first and second spaces 25, 26 of the first header tank 3 becomes greater than the pressure in the refrigerant inflow space 24, and the communication port is provided at the lower end portion of the branch flow control member 21, the refrigerant inflow space 24 and the interiors of the first heat exchange tubes 2A of the third heat exchange path P3 can be filled with liquid phase refrigerant before the level of the predominant liquid phase of the mixed refrigerant in the first and second spaces 25, 26 reaches a point above the first heat exchange tube of the upper end 2A of the third heat exchange path P3.Consequently, the interiors of the first heat exchange tubes 2A of the coolant subcooling path can be quickly filled with the liquid-phase coolant, whereby the amount of coolant supplied to the refrigeration cycle can be increased at an early stage to an appropriate level at which the degree of subcooling becomes constant. Furthermore, since the amount of coolant supplied to the refrigeration cycle can be increased at an early stage to an appropriate level at which the degree of subcooling becomes constant, the width of the stable range in which the degree of subcooling becomes constant, that is, the range of the amount of coolant supplied in which the degree of subcooling becomes constant, becomes larger, whereby a subcooling characteristic more stable against load fluctuations and / or coolant leakage can be obtained.

Claims

[1] Condenser having a condensing region and a subcooling region arranged such that the condensing region is positioned above the subcooling region, and having a plurality of Heat exchange tubes arranged parallel to each other such that the heat exchange tubes are spaced apart from each other in a vertical direction and extend in a left / right direction; and head tanks extending in the vertical direction and to which left and right end portions of the heat exchange tubes are connected, wherein three or more heat exchange paths each formed by a plurality of heat exchange tubes arranged one after the other in the vertical direction, adjacent to each other in the vertical direction, two or more heat exchange paths are provided in the condensation area, each of the heat exchange paths provided in the condensing section serves as a refrigerant condensation path for condensing refrigerant, the heat exchange path(s) provided in the subcooling area serves as a coolant subcooling path for subcooling coolant, a first header tank and a second header tank are provided at a left end portion or right end portion of the condenser, the heat exchange tubes of the coolant subcooling path and the heat exchange tubes of the lower-end coolant condensing path are connected to the first header tank, the heat exchange tubes of the coolant condensation path(s), excluding the lower end coolant condensation path, are connected to the second header tank, the first head tank is arranged on the outside of the second head tank with respect to the left / right direction, an upper end of the first head tank is arranged above a lower end of the second head tank and a desiccant container containing a desiccant is arranged in the first head tank, wherein a branch flow control member is provided in the first header tank to be arranged on the inside with respect to the left / right direction, the branch flow control member promoting a flow of the liquid phase refrigerant from the first header tank into the heat exchange tubes of the refrigerant subcooling path adjacent to the lower end refrigerant condensing path; the desiccant container is arranged in the first head tank to be located on the outside of the branch flow control member with respect to the left / right direction; a sealing portion for dividing an interior space of the first header tank into upper and lower spaces is provided between a peripheral wall of the first header tank and the branch flow control member and a peripheral wall of the desiccant container, whereby refrigerant that has flowed from the heat exchange tubes of the lower-end refrigerant condensation path into the first header tank flows into the desiccant container in a region above the sealing portion, flows from the desiccant container in a region below the sealing portion, and flows through the branch flow control member into the heat exchange tubes of the refrigerant subcooling path adjacent to the lower-end refrigerant condensation path; and a coolant inflow region is provided immediately above the sealing portion, wherein in this region the clearance between the peripheral wall of the first header tank and the peripheral wall of the desiccant container is larger than that in a region above the coolant inflow region, whereby coolant flows into the clearance between the peripheral wall of the first header tank and the peripheral wall of the desiccant container above the coolant inflow region into the coolant inflow region and then flows into the desiccant container. [2] The condenser according to claim 1, wherein a lower end of the branch flow control member is disposed below the heat exchange tube of the lower end of the refrigerant subcooling path adjacent to the lower end refrigerant condensing path; an upper end of the branch flow control member is disposed above the heat exchange tube of the upper end of the refrigerant subcooling path adjacent to the lower end refrigerant condensing path; at least a portion of the desiccant container is disposed within a vertical range over which the branch flow control member extends in the vertical direction; and the sealing portion is provided within the vertical range of the branch flow control member. [3] The condenser according to claim 2, wherein a refrigerant subcooling path is provided in the subcooling region; the branch flow control member is provided at a vertical position corresponding to the refrigerant subcooling path; the branch flow control member is provided in the first header tank in such a manner as to form a closed refrigerant inflow region that communicates with the heat exchange tubes of the refrigerant subcooling path and allows the refrigerant to flow into the heat exchange tubes of the refrigerant subcooling path; and a communication port is provided at a lower end portion of the branch flow control member to establish communication between the lower space of the first header tank, which is located below the sealing portion, and the refrigerant inflow space. [4] The condenser according to claim 3, wherein the branch flow control member includes a partition wall oriented so that its longitudinal direction coincides with the vertical direction and which divides the internal space of the first header tank into an inner and an outer space with respect to the left / right direction, and upper and lower closing walls provided at upper and lower ends of the partition wall for closing upper and lower end openings of the internal space positioned on the inner side of the partition wall with respect to the left / right direction; the partition wall and the upper and lower closing walls form the refrigerant inflow space; and the communication port is formed in one of the partition wall and the lower closing wall. [5] A condenser according to claim 3 or 4, wherein the refrigerant inflow portion is provided by forming a recess in the peripheral wall of the desiccant tank; a first inflow port is formed in the peripheral wall of the desiccant tank at a position above the recess so that the refrigerant that has flowed from the heat exchange tubes of the lower-end refrigerant condensing path into the first header tank flows into the desiccant tank through the first inflow port; a second inflow port is formed in the peripheral wall of the desiccant tank at a position corresponding to the recess so that refrigerant that has been introduced into the recess flows into the desiccant tank through the second inflow port;and an outflow opening is formed in the peripheral wall of the desiccant container in a region below the sealing portion so that refrigerant flows from the space inside the desiccant container through the outflow opening into the space inside the first header tank; [6] The condenser according to claim 1, wherein the first header tank is constructed of a tubular main body having a closed upper end and an open lower end, and a lower closure member detachably attached to the lower end of the tubular main body to close the lower end opening of the tubular main body; a lower end of the desiccant container is positioned below a lower end of the branch flow control member; and rattling noise preventing means is provided on the desiccant container at a position below the branch flow control member, the rattling noise preventing means extending between the branch flow control member and the lower closure member of the first header tank to thereby prevent rattling noise from the desiccant container. [7] A condenser according to claim 6, wherein the rattling noise preventing means is pressed from the upper side by the branch flow control member and is pressed from the lower side by the lower closure member of the first header tank, whereby the rattling noise preventing means is elastically deformed; and rattling of the desiccant container is prevented by an elastic restoring force of the rattling noise preventing means. [8] A condenser according to claim 7, wherein the rattling noise preventing means includes an upper rattling noise preventing arm provided on the desiccant container and having a distal end portion in contact with the lower end portion of the branch flow control member from the lower side thereof, and a lower rattling noise preventing arm provided on the desiccant container and having a distal end portion in contact with the lower closure member from the upper side thereof.

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