Connecting device for heat exchanger

Abstract: A connecting device (C1) for a heat exchanger (1) which has a fluid circulating channel (2) formed with an opening (3) at one end thereof and an opening (4) at the other end thereof, the openings (3,4) being formed as juxtaposed in one side of the heat exchanger (1). The connecting device (C1) comprises a blocklike connector body (7) having two horizontal through bores (5,6) corresponding to the respective openings (3,4) and fixed to the heat exchanger (1) with the through bores (5,6) in coincidence with the respective openings (3,4). A tubular member (8,9) is fluid-tightly fitted in each of the through bores (5,6) and has a connecting end projecting toward a connectable device (10). The connecting end is in the form of a spigot (13,14) fittable in a socket (11,12) of the connectable device (10).

Description: BACKGROUND OF THE INVENTION The present invention relates to connecting devices for heat exchangers such as evaporators and condensers as described in the preamble of claim 1. Such connecting devices are known for instance from EP-A-0 703 425. The term "aluminum" as used herein and in the claims includes pure aluminum and aluminum alloys. For use with heat exchangers having a fluid circulating channel and two openings of respective opposite ends of the channel formed as juxtaposed in one side of the heat exchanger, a connecting device is known which comprises a connector having two horizontal through bores corresponding to the respective openings and fixed to the heat exchanger with the through bores in coincidence with the respective openings. The connector comprises a blocklike body adjacent to the heat exchanger, and two short tubular projections provided on the connector body around edges thereof defining the respective through bores and to be opposed to a connectable device, each of the tubular projections being in the form of a spigot fittable in a socket of the connectable device. Since the connector has the structure described above, the two spigot portions must be made from a large block of material by cutting. This not only causes waste of a large quantity of the material but also gives rise to the problem that after one of the spigot portions has been formed by cutting, this spigot portion interferes with the cutting operation for making the other spigot portion. EP 0 703 425 A1 relates an expansion valve mounting member and discloses a connecting device consisting of a plate member having a pair of through bores. A tubular member is fitted into each of the through bores and fixed therein by brazing or by press fitting. The tubular members project from one main surface of the plate member to form spigots to be inserted into corresponding sockets of an expansion valve. In addition, the other end of the tubular member projects from the other main surface of the plate member to form an annular flange to be inserted into a hole provided in a heat exchanger. US 5,477,919 is concerned with a heat exchanger and discloses a joint having a first and a second through bore. Each of the through bores is formed for receiving a spigot or short cylindrical profusion of a connector means having a receiving port into which the end of an external piping is forced. Alternatively the ends of the external pipings may be brazed to, welded to or otherwise fixed in the receiving ports. SUMMARY OF THE INVENTION The object of the present invention is to provide a heat exchanger with a connecting device and a connecting device as such which is easy to make and to handle when connecting the connectable device to the heat exchanger. This object is achieved by the subject matter of claim 1 and claim 9. Inparticular, according to the present invention a tubular member is simply fitted in each of a pair of through bores and has a connecting end projecting so as to face a connectable device. Therefor, the spigot of the tubular member and the portion thereof fitted in the through bore are each formed with an annular groove, in which an O-ring is fitted. Thus, the fluid tight fit of the tubular member in the through bore is simply realized by the O-ring. The present invention will be described below in greater detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a multilayer evaporator as a heat exchanger provided with a connecting device of the invention, i.e., Embodiment 1; FIG. 2 is a plan view partly broken away and showing the connecting device of FIG. 1 and an expansion valve of the block type as a connectable device before the valve is connected to the heat exchanger; FIG. 3 is a plan view partly broken away and showing another connecting device of the invention, i.e., Embodiment 2, in an exploded state along with a connectable device in the same state as in FIG. 2; FIG. 4 is a plan view partly broken away and showing another connecting device of the invention, i.e., Embodiment 3; FIG. 5 is an exploded view in horizontal section of the connecting device of FIG. 4 to show the order of assembly; FIG. 6 is a front view of a condenser provided with a supercooling unit and serving as a heat exchanger which has another connecting device of the invention, i.e., Embodiment 4; FIG. 7 is a front view partly broken away and showing the connecting device of FIG. 6 and a liquid receiver as a connectable device before the receiver is connected to the heat exchanger; FIG. 8 is a front view partly broken away and showing another connecting device of the invention, i.e., Embodiment 5, and a liquid receiver different from that of FIG. 7 and serving as a connectable device before the receiver is connected to the heat exchanger; and FIG. 9 is a view in section partly broken away, corresponding to FIG. 2 and showing a conventional connecting device. DESCRIPTION OF THE PREFERRED EMBODIMENTS For a better understanding of the present invention, a conventional connecting device C for a heat exchanger 1 will be described with reference to FIG. 9 before the description of the invention. The heat exchanger 1 has a fluid circulating channel formed with an opening 3 at one end thereof and an opening 4 at the other end thereof, the openings 3, 4 being formed as juxtaposed in one side of the heat exchanger 1. The illustrated connecting device C comprises a connector 72 having two horizontal through bores 70, 71 corresponding to the respective end openings 3, 4 and fixed to the heat exchanger 1 with the through bores,70, 71 in coincidence with the respective openings 3, 4. The connector 72 comprises a blocklike connector body 73 adjacent to the heat exchanger 1, and two short tubular projections provided on the connector body 73 around edges thereof defining the respective through bores 70, 71 and to be opposed to a connectable device, the tubular projections being in the form of spigots 74, 75 fittable in respective sockets of the connectable device. Since the two spigot portions 74, 75 must be formed by cutting a large block of material, the connector 72 has the foregoing problem. The heat exchangers and connecting devices to be described below with reference to the following embodiments are all made from aluminum. Embodiment 1 FIGS. 1 and 2 show this embodiment, i.e., a connecting device C1, for use with a heat exchanger 1 shown which has a fluid circulating channel 2 formed with an opening 3 at one end thereof and an opening 4 at the other end thereof, the openings 3, 4 being formed as juxtaposed in one side wall of the heat exchanger 1. The connecting device C1 comprises a blocklike connector body 7 having two horizontal through bores 5, 6 corresponding to the respective openings 3, 4 and fixed to the heat exchanger 1 with the through bores 5, 6 in coincidence with the respective openings 3, 4. Tubular members 8, 9 are fluid-tightly fitted in the respective through bores 5, 6, with connecting ends thereof projecting toward a connectable device 10 (i.e., device to be connected to the exchanger 1). The connecting ends of the tubular members 8, 9 are in the form of spigots 13, 14 fittable in respective sockets 11, 12 of the connectable device 10. The side wall of the heat exchanger 1 has an edge defining each of the openings 3, 4 and formed with an annular projection 15, and the connector body 7 has an edge defining each of the through bores 5, 6 and formed with an annular projection 16. The former annular projection 15 is fitted in and brazed to the latter annular projection 16 in lapping relation to thereby fix the connector body 7 to the heat exchanger 1. The connector body 7 is in the form of a horizontally elongated circle when seen from one side, and in the form of a horizontally elongated rectangle except the two annular projections 16 when seen from above. The connector body 7 is obtained by cutting an aluminum extrudate to a predetermined size and further cutting the resulting block as specified. The spigot 13 (14) of each tubular member 8 (9) and the portion 17 (18) thereof fitted in the through bore 5 (6) are each formed with an annular groove 19, and an O-ring 20 is fitted in the annular groove 19. The fluid-tight fit of the tubular member 8 (9) in the through bore 5 (6) is realized by the O-ring 20. An annular positioning flange 21 is formed on the outer periphery of the tubular member 8 (9) approximately at the lengthwise midportion thereof, and the inner peripheral surface of the connector body 7 defining the through bore 5 (6) is formed with an annular stepped portion 22 for receiving the positioning flange 21. The through bore 5 (6) is tapered toward the bore end from the portion thereof where the extremity of the fitted portion 17 (18) of the tubular member 8 (9) therein is positioned, and the inner periphery of the connector body 7 defining the bore end is formed with an annular stepped portion for receiving the annular projection 15 around the opening 3 (4) of the fluid circulating channel 2. Embodiment 2 FIG. 3 shows this embodiment, i.e., a connecting device C2, for use with a heat exchanger 1. Unlike Embodiment 1, this embodiment has no annular positioning flange on the outer periphery of each of tubular portions 23, 24 approximately at the midportion thereof, and the inner periphery defining each of through bores 25, 26 correspondingly has no positioning flange bearing stepped portion. With the exception of this feature, Embodiment 2 is substantially the same as Embodiment 1. Embodiment 3 FIGS. 4 and 5 show this embodiment, i.e., a connecting device C3, for use with a heat exchanger 1 shown which has a fluid circulating channel 2 formed with an opening 3 at one end thereof and an opening 4 at the other end thereof, the openings 3, 4 being formed as juxtaposed in one side wall of the heat exchanger 1. The connecting device C3 comprises a blocklike connector body 29 having two horizontal through bores 27, 28 corresponding to the respective openings 3, 4 and provided for the heat exchanger 1 with the through bores 27, 28 in coincidence with the respective openings 3, 4. Tubular members 30, 31 are fluid-tightly fitted in the respective through bores 27, 28, with connecting ends thereof projecting toward a connectable device 10 (i.e., device to be connected to the exchanger 1). The connecting ends of the tubular members 30, 31 are in the form of spigots 13, 14 fittable in respective sockets of the connectable device 10. The tubular members 30, 31 are fixed to the heat exchanger 1. The side wall of the heat exchanger 1 has an edge defining each of the openings 3, 4 and formed with an annular projection 15, and the connector body 29 has an edge defining each of the through bores 5, 6 and provided with an annular projection 32. The former annular projection 15 is fitted in and brazed to the latter annular projection 32 in lapping relation to thereby fix each tubular member 30 (31) to the heat exchanger 1. The annular projection 32 has a larger outer periphery than the tubular member 30 (31), whereby a connector body receiving stepped portion 32 is formed. The annular projection 32 has a larger inner periphery than the tubular member 30 (31), whereby an annular stepped portion is formed in the inner periphery of the edge of the bored portion for receiving the annular projection 15 around the opening 3 (4) of the channel 2. Each of the tubular members 30, 31 has an annular groove 19 formed in its spigot 13 (14) and an O-ring 20 fitted in the annular groove 19. The fluid-tight fit of the tubular member 30 (31) in the through bore 27 (28) is realized by enlarging the portion 34 (35) of the tubular member 30 (31) fitted in the through bore 27 (28). The portion 34 (35) is enlarged using a usual jig useful for enlarging pipes or tubes. The connecting device C3 is assembled in the order shown in FIG. 5 by inserting the tubular members 30, 31 through the respective bores 27, 28 of the blocklike connector body 29 as indicated by arrows in the drawing to engage the stepped portions 33 with the edges of the respective bored portions of the connector body 29. When the tubular members 30, 31 are fixed to the heat exchanger 1 by brazing, the connector body 29 is consequently received by the stepped portions 33. The O-rings 20 are fitted into the respective annular grooves 19 after the tubular members 30, 31 have been fixed to the heat exchanger 1. The blocklike connector body 29 of the present embodiment is identical with the connector body 7 of Embodiment 1 in shape when seen from one side, and is perfectly in the form of a horizontally elongated rectangle when seen from above. Accordingly, the body 29 has no portion which needs to be made by cutting. Throughout Embodiments 1 to 3, the heat exchanger 1 is a multilayer evaporator, while the connectable device 10 is an expansion valve of the block type. The spigot 13 provides an inlet for a fluid, and the other spigot 14 provides an outlet for the fluid. In connection with Embodiments 1 to 3, like parts are designated by like reference numerals and are not described repeatedly. Embodiment 4 FIGS. 6 and 7 show this embodiment, i.e., a connecting device C4, for use with a heat exchanger 36 shown which has as arranged at one side thereof a vertical upper header 37 and a vertical lower header 38 integral therewith. The upper header 37 and the lower header 38 have a lower-end opening 39 and an upper-end opening 40, respectively, as arranged in a vertical row. The connecting device C4 comprises a blocklike connector body 43 in the form of a vertically elongated rectangle in vertical section, having two through bores 41, 42 corresponding to the respective openings 39, 40 and fixed to the heat exchanger 36 with the through bores 41, 41 in coincidence with the respective openings 39, 40. Tubular members 44, 45 are fluid-tightly fitted in the respective through bores 41, 42 and each have a connecting end projecting toward a connectable device 46. The connecting ends are in the form of spigot 49, 50 fittable in respective sockets 47, 48 of the connectable device 46. A member 51 in the form of a short tube for positioning the connector body 43 is fixedly fitted in each of the openings 39, 40 so as to project into the header by a short length and into the connector body 43 by a long length. The connector body 43 has an inner peripheral surface defining each of the through bores 41, 42 and formed with an annular stepped portion 52 for receiving the positioning member 51, the bore-defining peripheral surface being formed, at one side thereof opposite to the positioning member 51, with an annular stepped portion 55 for receiving the portion 53 (54) of the tubular member 44 (45) fitted in. The spigot 49 (50) of the tubular member 44 (45) and the portion 53 (54) thereof fitted in the through bore 41 (42) are each formed with an annular groove 56, and an O-ring 57 is fitted in the annular groove 56. The fluid-tight fit of the tubular member 44 (45) in the through bore 41 (42) is realized by the O-ring 57. The upper header 37 is separated from the lower header 38 by a partition 58. Embodiment 5 FIG. 8 shows this embodiment, i.e., a connecting device C5. In the case of Embodiment 4, the connectable device 46 has the sockets 47, 48 in the outer periphery of its lower portion, whereas with this embodiment, sockets 60, 61 are formed in the bottom of a connectable device 59. Accordingly, the device C5 comprises a connector body 62 which is approximately square in vertical section and formed with L-shaped through bores 63, 64. The upper end of the connector body 62 has an inner peripheral surface defining each of each through bore 63 (64) and formed with an annular stepped portion 65, which faces upward for receiving the portion 53 (54) of each tubular member 44 (45) fitted in the connector body 62. With the exception of this feature, Embodiment 5 is substantially the same as Embodiment 4. In connection with Embodiments 4 and 5, like parts are designated by like reference numerals and will not be described repeatedly. In the case of Embodiments 4 and 5, the heat exchanger 36 is a condenser having a supercooling unit which is provided by the portion of the heat exchanger below a horizontal plane through the boundary between the upper header 37 and the lower header 38, while each of the connectable devices 46, 59 is a liquid receiver. The spigot 49 provides an outlet for a fluid, i.e., the refrigerant subjected to condensation by the condenser, and the other spigot 50 provides an inlet of the supercooling unit 66 for the fluid, i.e., the refrigerant as passed through the receiver, that is, as purified. The tubular members 8, 9, 23, 24, 30, 31, 44, 45 of Embodiments 1 to 5 are each obtained by cutting a hollow aluminum extrudate to a predetermined size and further cutting the resulting piece as specified.

Claims: A connecting device (C1; C2; C4; C5) comprising: a blocklike connector body (7, 43, 62) having two through bores (5, 6; 25, 26; 41, 42; 63, 64) being formed as arranged in a row corresponding to respective openings (3, 4; 39, 40) in one side of a heat exchanger (1, 36), the connector body (7, 43, 62) can be fixed to the heat exchanger (1; 36) with the through bores (5, 6; 25, 26; 41, 42; 63, 64) in coincidence with the respective openings (3, 4; 39, 40). two tubular members (8, 9; 23, 24; 44, 45), each being fitted in one of the through bores (5, 6; 25, 26; 41, 42; 63, 64) and having a connecting end projecting toward a connectable device (10, 46, 59), the connecting ends being in the form of spigots (13, 14; 49, 50) fittable in respective sockets (11, 12: 47, 48; 60, 61) of the connectable device (10, 46, 59), characterized in that the spigots (13, 14; 49, 50) of the tubular members (8, 9; 23, 24; 44, 45) and the portions (17, 18; 53, 54) thereof fitted in the through bores (5, 6; 25, 26; 41, 42; 63, 64) of the blocklike connector body (7, 43, 62) are each formed with an annular groove (19, 56), and an O-ring (20, 57) is fitted in each of the annular grooves (19, 56), so that a fluid-tight fit of the tubular members (8, 9; 23, 24; 44, 45) in both the through bores (5, 6; 25, 26; 41, 42; 63, 64) of the blocklike connector body (7, 43, 62) and in the sockets (11, 12: 47, 48; 60, 61) of the connectable device (10, 46, 59) being realized by the O-rings (20, 57). A connecting device (C1; C2; C4) according to claim 1 characterized in that the two through bores (5, 6; 25, 26; 41, 42) of the blocklike connector body (7, 43) are horizontal. A connecting device (C1) according to claim 1 characterized in that an annular positioning flange (21) is formed on an outer periphery of each of the tubular members (8, 9) approximately at a lengthwise midportion thereof, and inner peripheral surfaces of the connector body defining the through bores (5, 6) are formed with an annular stepped portion (22) for receiving a respective one the positioning flanges (21). A connecting device (C4; C5) according to claim 1, characterized in that . positioning members (51) in the form of a short tube for positioning the connector body (43, 62) are fixedly fitted in each of the two openings (39, 40) so as to project toward the heat exchanger (36) by a short length and into the connector body (43, 62) by a long length. A connecting device (C4; C5) according to claim 4, characterized in that the connector body (43, 62) has inner peripheral surfaces defining each of the through bores (41, 42; 63, 64), being formed with an annular stepped portion (52) for receiving the positioning member (51) and being formed at one side thereof opposite to the positioning member (51) with an annular stepped portion (55, 65) for receiving respective portions (53, 54) of the tubular members (44, 45) fitted in. A connecting device (C4) according to claim 5, characterized in that the connector body (43) is in the form of a vertically elongated rectangle in vertical section, and the two through bores (41, 42) are horizontal. A connecting device (C5) according to claim 5, characterized in that the connector body (62) is approximately square in vertical section, and the two through bores (63, 64) are each L-shaped. A heat exchanger having two openings (3, 4; 39, 40) being formed as arranged in a row in one side of the heat exchanger (1. 36), and a connecting device (C1: C2; C4: C5) according to any one of the preceding claims fixed to the heat exchanger (1; 36) with the through bores (5, 6; 25, 26; 41, 42; 63, 64) of the connector body (7, 43, 62) in coincidence with the respective openings (3, 4: 39, 40). A heat exchanger according to claim 8, characterized in that one opening (3) of two openings (3, 4) is an opening at one end of a fluid circulating channel (2) of the heat exchanger and the other opening (4) is an opening at the other end of the fluid circulating channel (2). A heat exchanger according to claim 8, characterized in that the heat exchanger (1) is a multilayer evaporator, the connectable device (10) is an expansion valve of the block type, the spigot (13) of one of the tubular members providing an inlet for a fluid, and the spigot (14) of the other tubular member providing an outlet for the fluid. A heat exchanger according to claim 8, 9, or 10, characterized in that an edge defining each of the openings (3, 4) and an edge defining each of the through bores (25, 26) are each formed with an annular projection (15; 16), and the annular projection (15) of the former is fitted in and brazed to the annular projection (16) of the latter in lapping relation, whereby the connector body (7) is fixed to the heat exchanger body. A heat exchanger according to claim 8, characterized in that one opening (39) of the two openings (39, 40), is a lower end opening (39) of a vertical upper header (37) arranged at one side of the heat exchanger (36) and the other opening (40) is an upper end opening (40) of a vertical lower header (38) integral with the upper header (37). A heat exchanger according to claim 12, characterized in that the heat exchanger (36) being a condenser having a supercooling unit which is provided by the portion of the heat exchanger (36) below a horizontal plane through a boundary between the upper head (37) and the lower header (38), the connectable device (46, 59) being a liquid receiver.

Inventors: ICHIYANAGI SHIGEHARU, ICHIYANAGI, SHIGEHARU
Applicants: SHOWA DENKO KK, SHOWA DENKO K.K.
Application year: 1999
Main classification: F28D1
IPC codes: F28F9, F28D1