Assembly comprising a heat exchanger and an expansion valve for a vehicle

Abstract

An assembly comprising a heat exchanger (10) and an expansion valve (20) for a vehicle, and further comprising a device for coupling the expansion valve (20) to the heat exchanger (10), wherein the coupling device comprises: a junction block (30) coupled to the expansion valve (20) and to the heat exchanger (10); and a securing plate (40) comprising an engagement portion (45a) configured to simultaneously engage flanged portions (12b, 13b) of a first tube (12) and a second tube (13), the securing plate (40) being fixable to the heat exchanger (10) by at least one screw (46) so as to hold the first tube (12), the second tube (13), the expansion valve (20), and the junction block (30) between the heat exchanger (10) and the securing plate (40).

Description

[0001] This invention relates in general to air conditioning systems for motor vehicles and, in particular, it relates to an assembly comprising a heat exchanger and an expansion valve for a vehicle, wherein the heat exchanger comprises at least one outlet port and at least one inlet port, wherein the expansion valve comprises an exchanger side facing the heat exchanger, and a circuit side opposite the exchanger side and intended to receive a first tube and a second tube, and wherein the assembly further comprises a device for coupling the expansion valve to the heat exchanger.

[0002] Said coupling device comprises: a junction block having an exchanger side intended to couple with said at least one outlet port and at least one inlet port, and a valve side opposite the exchanger side and intended to couple with the expansion valve, said junction block being a one-piece body through which a plurality of fluid passages is obtained to fluidically connect the expansion valve to said at least one outlet port and at least one inlet port; and a securing plate comprising an engagement portion configured to simultaneously engage flanged portions of the first tube and of the second tube, the securing plate being fixable to the heat exchanger by at least one screw to hold the first tube, the second tube, the expansion valve, and the junction block between the heat exchanger and the securing plate.

[0003] An assembly according to the preamble of claim 1 is described in JP H08 14703 A or in US 11754204 B2.

[0004] The assembly according to the invention is characterized in that said at least one screw has a smooth shank provided with a threaded tip, wherein respective through holes are obtained in the securing plate, in the expansion valve and in the junction block that are configured to receive said at least one screw, wherein at least one threaded hole is obtained on the heat exchanger configured to be engaged by the threaded tip of said at least one screw.

[0005] In the assembly according to the invention, the position of the expansion valve is moved close to the heat exchanger (evaporator), and therefore inside the perimeter of the air conditioning unit, thus simplifying the interface between the passenger compartment and the engine compartment, at which it will therefore be required to simply pass the pair of aforesaid tubes (first tube and second tube) wherewith, in the engine compartment, the heat exchanger will connect to a circuit for circulating a refrigerant fluid installed in a motor vehicle. Furthermore, the solution according to the invention allows the heat exchanger, the metal junction block, the expansion valve and the aforesaid tubes to be integrally constrained by means of the use of a limited number of screws, without the need for welding or further joining.

[0006] Other features and advantages of the assembly according to the invention will become apparent from the following detailed description of an embodiment of the invention, made with reference to the accompanying drawings, which are provided for illustrative and non-limiting purposes only, wherein Figure 1 is a perspective view of an assembly according to the invention; and Figures 2 and 3 are exploded views of the assembly in Figure 1.

[0007] Figures 1-3 show an assembly comprising a heat exchanger 10 of an air conditioning unit, for example an evaporator (not shown), which may be connected to a circuit for circulating a refrigerant fluid installed in a motor vehicle (not shown). For this purpose, the assembly comprises a pair of tubes 12 and 13 made of a metallic material (e.g., one outlet from the heat exchanger and one inlet to the heat exchanger). The heat exchanger 10 comprises, for example, a bundle of tubes 14 that extends between opposite headers 15, 16 and that is arranged between a pair of side plates 17, 18. As may be seen in particular in Figures 2 and 3, the heat exchanger 10 further comprises at least one outlet port 10a and at least one inlet port 10b, respectively for the outlet of the refrigerant fluid from the heat exchanger 10 and for the inlet of the refrigerant fluid into the heat exchanger 10, which are fluidically connected using the tubes 12 and 13 and which hereinafter will be designated as the first and second tubes. As regards the heat exchanger 10, the outlet and inlet ports 10a, 10b are connected to two respective separate sections of one of the headers 15, 16. From a construction point of view, the outlet and inlet ports 10a, 10b are obtained on a connection element 19 made of a metallic material, which is welded to a side plate and / or a header of the heat exchanger 10. In particular, the outlet and inlet ports 10a, 10b are obtained as bushing portions protruding from the connection element 19.

[0008] The assembly further comprises an expansion valve 20 of a type known per se, and wherein there may be identified an exchanger side 21 facing the heat exchanger 10, and a circuit side 22 opposite the exchanger side 21 and intended to receive the first tube 12 and the second tube 13. The exchanger side 21 of the expansion valve 20 comprises a first exchanger side bore 23 and a second exchanger side bore 24, whilst the circuit side 22 of the expansion valve 20 comprises a first circuit side bore 25 and a second circuit side bore 26. The aforesaid bores 23, 24, 25, 26 are fluidically connected to internal passages obtained in the expansion valve 20, and wherealong moving elements are arranged, in a manner known per se, so as to achieve the usual functionalities of an expansion valve. In the figures, the numeral 28 denotes an actuator of the expansion valve.

[0009] The first tube and the second tube 12, 13 each comprise an end 12a, 13a adjacent to a flanged portion 12b, 13b extending radially outwards. Such flanged portions are obtained on the tubes using conventional tube processing techniques.

[0010] The assembly further comprises a coupling device that forms the mechanical coupling between the heat exchanger 10 and the expansion valve 20, without the use of welding. Said coupling device essentially comprises a junction block 30 and a securing plate 40.

[0011] The junction block 30 is a one-piece body made of a metallic material and comprises an exchanger side 31 intended to couple with the outlet and inlet ports 10a, 10b of the heat exchanger 10, and a valve side 32 opposite the exchanger side 31 and intended to couple with the expansion valve 20. At least one pair of fluid passages are obtained through the junction block 30 to fluidically connect the expansion valve 20 to the outlet and inlet ports 10a, 10b of the heat exchanger 10. Such fluid passages lead, on the exchanger side 31 of the junction block 30, to a first exchanger side bore 33 and a second exchanger side bore 34, and, on the valve side 32 of the junction block 30, to a first valve side bushing protrusion 35 and a second valve side bushing protrusion 36.

[0012] In the assembled condition of the assembly described above, the inlet and outlet ports 10a, 10b of the heat exchanger 10 are inserted into the first exchanger side bore 33 and into the second exchanger side bore 34 of the junction block 30, respectively, the first valve side bushing protrusion 35 and the second valve side bushing protrusion 36 of the junction block 30 are inserted into the first exchanger side bore 23 and the second exchanger side bore 24 of the expansion valve 20, respectively, and the flanged ends of the first tube 12 and the second tube 13 are inserted into the first circuit side bore 25 and second circuit side bore 26 of the expansion valve 20, respectively.

[0013] The securing plate 40 is made of a metallic material, which comprises an engagement portion 45a configured to simultaneously engage the flanged portions 12b, 13b of the first tube and of the second tube 12, 13. A pair of brackets 45b, 45c is obtained in the securing plate 40 having transverse dimensions slightly larger than the outer diameter of the first tube 12 and the second tube 13, respectively, but smaller than the outer diameter of the flanged portions, 12b and 13b, respectively. This allows the securing plate 40 to be assembled to the tubes 12 and 13 and to be moved along such tubes until it is brought into engagement with the flanged portions 12b and 13b. In practice, the engagement portion 45a provided by the securing plate 40 is composed of portions of the surface of such plate facing the expansion valve 20, which are arranged around the edges of the brackets 45b, 45c.

[0014] The securing plate 40 is fixed to the heat exchanger 10 by at least one screw 46 (in the example, two screws) in order to hold the first tube 12 and the second tube 13, the expansion valve 20 and the junction block 30 between the heat exchanger 10 and the securing plate 40. To this end, each of the screws 46 has a smooth shank 46a provided with a threaded tip 46b, whilst in the securing plate 40, in the expansion valve 20, and in the junction block 30 respective through holes 49, 29, 39 are obtained which allow for the positioning of the screws 46, whilst in the connection element 19 of the heat exchanger 10 threaded holes 19d are obtained, wherein the threads thereof are engaged by the threaded tips 46b of the screws 46. In this way, the screws 46 act as tie rods that apply a clamping force that acts upon the heads of the screws at the securing plate 40, and upon the tips of the screws at the connection element 19 of the heat exchanger 10. The screws 46 therefore allow the securing plate 40 to be tightened against the flanged portions 12b, 13b of the tubes 12, 13 thereby tightening such flanged portions against the expansion valve 20. It should be noted that no other screws are required for the integrity of the assembly described above other than those used for fixing the securing plate 40 to the heat exchanger 10.

[0015] Referring to Figure 2, a first gasket 52 is suitable for being interposed between the radially outer surface of the end 12a of the first tube 12 and the radially inner surface of the first circuit side bore 25 of the expansion valve 20. A second gasket 53 is suitable for being interposed between the radially outer surface of the end 13a of the second tube 13 and the radially inner surface of the second circuit side bore 26 of the expansion valve 20. A third gasket 62 is suitable for being interposed between the radially outer surface of the first valve side protrusion 35 of the junction block 30 and the radially inner surface of the first exchanger side bore 23 of the expansion valve 20. A fourth gasket 63 is suitable for being interposed between the radially outer surface of the second valve side protrusion 36 of the junction block 30 and the radially inner surface of the second exchanger side bore 24 of the expansion valve 20.

Claims

1. Assembly comprising a heat exchanger (10) and an expansion valve (20) for a vehicle, wherein the heat exchanger (10) comprises at least one outlet port (10a) and at least one inlet port (10b), wherein the expansion valve (20) comprises an exchanger side (21) facing the heat exchanger (10) and a circuit side (22) opposite the heat exchanger side (21) and intended to receive a first tube (12) and a second tube (13), and wherein the assembly further comprises a device for coupling the expansion valve (20) to the heat exchanger (10), the assembly being characterized in that said coupling device comprises: a junction block (30) having a heat exchanger side (31) intended to couple with said at least one outlet port (10a) and said at least one inlet port (10b), and a valve side (32) opposite the heat exchanger side (31) and intended to couple with the expansion valve (20), said junction block (30) being a one-piece body of metallic material through which a plurality of fluid passages (25, 23; 26, 24) are formed for fluidically connecting the expansion valve (20) to said at least one outlet port (10a) and said at least one inlet port (10b); and a securing plate (40) comprising an engagement portion (45a) configured to simultaneously engage flanged portions (12b, 13b) of the first tube (12) and of the second tube (13), the securing plate (40) being fixable to the heat exchanger (10) by at least one screw (46) to hold the first tube (12), the second tube (13), the expansion valve (20) and the junction block (30) between the heat exchanger (10) and the securing plate (40); the assembly being characterized in that said at least one screw (46) has a smooth shank (46a) provided with a threaded tip (46b), wherein within the securing plate (40), within the expansion valve (20) and within the junction block (30) respective through holes (49, 20, 39) are obtained that are configured to receive said at least one screw (46), wherein at least one threaded hole (19d) is obtained upon the heat exchanger (10) that is configured to be engaged by the threaded tip (46b) of said at least one screw (46).

2. Assembly according to claim 1, wherein said at least one inlet port (10a) and said at least one outlet port (10b) of the heat exchanger (10) are configured to be inserted into a first exchanger side bore (33) and in a second exchanger side bore (34) of the junction block (30), respectively, said first exchanger side bore (33) and said second exchanger side bore (34) being obtained on the exchanger side (31) of the junction block (30).

3. Assembly according to claim 1 or 2, wherein the junction block (30) comprises a first valve side bushing protrusion (35) and a second valve side bushing protrusion (36) configured to be inserted into a first exchanger side bore (23) and into a second exchanger side bore (24) of the expansion valve (20), respectively, wherein said first valve side bushing protrusion (35) and said second valve side bushing protrusion (36) are obtained on the valve side (32) of the junction block (30), and wherein said first exchanger side bore (23) and said second exchanger side bore (24) are obtained on the exchanger side (21) of the expansion valve (20).

4. Assembly according to any one of the preceding claims, wherein ends (12a) of the first tube (12) and of the second tube (13) adjacent to said flanged portions (12b, 13b) are configured to be inserted into a first circuit side bore (25) and into a second circuit side bore (26) of the expansion valve (20), respectively, said first circuit side bore (25) and said second circuit side bore (26) being obtained on the circuit side (22) of the expansion valve (20).

5. Assembly according to any one of the preceding claims, wherein a pair of curved brackets (45b,45c) is obtained in the securing plate (40), the brackets being configured to receive the first tube (12) and the second tube (13) respectively.

6. Assembly according to any one of the preceding claims, wherein said at least one outlet port (10a) and said at least one inlet port (10b) of the heat exchanger (10) are obtained on a connection element (19) welded to a side plate (17) or to a header (15) of the heat exchanger (10).

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