Housing assembly for a heat exchange system

Abstract

The invention relates to a housing assembly for a heat exchange system. The housing assembly includes an aluminum housing having at least two fluid ports, where each fluid port is connected to a bimetallic connector, where the bimetallic connector includes an inner copper layer and an outer stainless steel layer, and where the aluminum housing includes a connection portion for connecting the bimetallic connector.

Description

[0001] The present invention relates to a housing assembly for a heat exchange system, wherein the housing assembly comprises an aluminum housing having at least two fluid ports, wherein each fluid port is connected to a bimetallic connector, wherein the bimetallic connector comprises an inner copper layer and an outer stainless steel layer, and wherein the aluminum housing comprises a connecting portion for connecting the bimetallic connector.

[0002] The housing assembly for heat exchange systems is a pressure-tight compartment for components such as valves and / or sight glasses. These housing assemblies are designed to be used with refrigeration or air conditioning systems. They can be components of the corresponding system that are subject to system pressure and have the primary function of withstanding system pressure. There is typically no limitation on the ability of the components inside the housing to handle pressure. The housing assembly is typically made of brass so that they can be easily joined to copper fluid conduits. Typically, refrigeration systems or heat exchange systems have copper conduits in which refrigerant fluid flows. Valve housings and other housings are typically made of brass.

[0003] The housing assembly may have secondary functions such as providing flow paths, guiding surfaces, sliding surfaces, and similar mechanical, thermal, flow-related or thermodynamic functions. A typical refrigeration valve housing assembly or a line component housing assembly will have one or more fluid ports, depending on the required function and / or design. These fluid ports are used to connect the internal cavity (i.e., the pressurized portion of the housing assembly) to the system to which the housing assembly is connected. When connecting a line component or valve to a system, brazing is the industry installation standard, although other principles exist, such as glue / sealant-based methods, threaded connections, flare-type connectors, etc.

[0004] When installing a valve having a brass body and copper connector in a refrigeration system having copper conduits in the art, typical challenges encountered are: the valve connector being brazed away from the brass body and a large amount of heat being introduced, which may damage components within the valve, such as O-rings and gaskets.

[0005] Instead of using brass for the housing, aluminum housing components may be used for example for cost reasons or to reduce the lead content in the housing alloy.These aluminum housings typically still need to be fluidly connected to copper conduits on site in the heat exchange system.

[0006] This can lead to problems with the connection of the different materials of the housing and the copper conduit. For example, galvanic corrosion may occur on the outer surface of the aluminum component. Existing heat conduction problems are also made worse because aluminum conduits conduct heat better than brass conduits.

[0007] Once the conduit is joined to the housing, the joint needs to be cleaned and, in the case of a friction welded joint for example, excess material needs to be removed. In addition, to ensure that the housing assembly operates correctly, it needs to be leak tested before use. The above items are typically difficult to handle in the art, especially for joining components of different materials.

[0008] The object of the present invention is to overcome the above mentioned problems. This object is achieved by an improved housing assembly according to claim 1 and a kit according to claim 7. Preferred embodiments are defined by the dependent claims.

[0009] According to claim 1, a housing assembly for a heat exchange system is proposed. The housing assembly comprises an aluminum housing having at least two fluid ports, wherein each fluid port is connected to a bimetallic connector, wherein the bimetallic connector comprises an inner copper layer and an outer stainless steel layer, and wherein the aluminum housing comprises a connecting portion for connecting the bimetallic connector.

[0010] The housing assembly described herein includes an aluminum housing or body and a connector of a different material than the aluminum housing. Highly specialized joining equipment can be used, for example, at the production site of the housing assembly to join the different material components of the housing assembly. This provides an opportunity to use joining methods that are not suitable in the art and may be difficult for some users of the housing assembly (such as OEMs) to handle.

[0011] The above problems of the prior art are solved by using a stainless steel connector with a copper coating on the inside. This coating can be applied mechanically. An alternative is to apply the coating via electroplating. However, this will place copper on both the inside and outside of the connector. Such a connector cannot be used due to galvanic corrosion on the outer surface of the aluminum component unless the copper is removed on the outside, for example mechanically.

[0012] When replacing the typical brass housing with an aluminum housing, there is more heat transfer and a greater risk of galvanic corrosion on the valve's exterior surface due to condensation on the valve housing exposed to atmospheric oxygen. These obstacles are overcome by using bimetallic connectors.

[0013] Bimetallic connectors are stainless steel tubes with, for example, a 40 micron copper layer. Bimetallic connectors reduce heat transfer because stainless steel is a much poorer conductor of heat than copper. Galvanic corrosion is also reduced because iron is closer to aluminum than copper components in terms of their respective electrochemical potentials.

[0014] The present invention makes it possible to utilize non-thermal assembly methods (such as friction welding or magnetic pulse welding), which have the advantage that these methods cannot be easily damaged or disengaged from the brazing when the housing assembly is installed in the field or at the OEM. Even if the housing assembly includes an aluminum housing, the housing assembly described herein can be easily connected to, for example, a copper tube. This means that standard methods for connecting a copper housing to a copper tube can be used to connect the aluminum housing of the housing assembly described herein to a copper tube via a connector. Therefore, from a practical point of view, the housing assembly described herein can be handled in the following manner, that is, as if it were made of brass and / or copper, rather than aluminum.

[0015] The present invention simplifies the replacement of a brass housing with an aluminum housing. Aluminum is cheaper than brass, and the price gap is expected to increase over time. In addition, aluminum can be more easily recycled than brass, and is therefore considered a better choice from an environmental perspective.

[0016] In a preferred embodiment of the present invention, the connecting portion comprises a threaded portion, a welding portion and / or a brazing portion. The connecting portions may be coaxially oriented relative to each other. The connecting portion may protrude from a central structure of the aluminum housing and / or may be integrally formed with the rest of the aluminum housing.

[0017] In another preferred embodiment of the present invention, the inner copper layer is brazed and / or welded to the aluminum housing. The connector may include a flange portion oriented in a radial direction of the connector. The inner copper layer may be at least partially disposed on the flange portion to contact the connection portion of the aluminum housing.

[0018] In another preferred embodiment of the present invention, the bimetallic connector is welded to the aluminum housing in the following manner: furnace brazing, conveyor belt brazing, induction brazing, laser brazing, filler-free laser welding, filler-containing laser welding, stir welding, spin welding, ultrasonic welding, electromagnetic pulse welding, TIG welding and / or MIG welding. Typically, a single joining technique can be used. However, a combination of two or more of the above joining techniques can be applied in alternative embodiments.

[0019] In another preferred embodiment of the present invention, the outer stainless steel layer covers all or most of the inner copper layer.The inner side of the stainless steel layer can be connected to the outer side of the inner copper layer via, for example, a material connection.

[0020] In another preferred embodiment of the present invention, the sleeve nut is screwed onto the threaded portion of the connecting portion, and a portion of the bimetallic connector is disposed between the sleeve nut and the connecting portion. Thus, the flange portion of the bimetallic connector can be used to receive pressure from the sleeve nut, thereby forcing the connector to abut against the connecting portion of the aluminum housing.

[0021] The invention also relates to a kit comprising an aluminium housing, at least one bimetallic connector and a sleeve nut for a housing assembly according to at least claim 6. The kit can be provided in a state in which its components are at least partially disconnected from each other. The user can connect the components according to existing requirements. The components can be arranged in a single dedicated packaging. Alternatively, the components can first be provided separately from each other and only combined at a later stage. Therefore, the components of the housing assembly of the present invention can be provided in a separate state, but still be covered by the scope of the present invention.

[0022] Further details and advantages of the invention are described with reference to the accompanying drawings. The drawings show:

[0023] Figure 1 : A perspective view of a first embodiment of a housing assembly;

[0024] Figure 2 : A cross-sectional view of a first embodiment of a housing assembly;

[0025] Figure 3 : A detailed cross-sectional view of a first embodiment of a housing assembly;

[0026] Figure 4 : A perspective view of a second embodiment of a housing assembly;

[0027] Figure 5 : a cross-sectional view of a second embodiment of a housing assembly; and

[0028] Figure 6 : Detailed cross-sectional view of a second embodiment of a housing assembly.

[0029] Figure 1 A perspective view of a first embodiment of a housing assembly is shown. The housing assembly is arranged for use in a heat exchange system, such as an air conditioning system, a heat pump or a refrigeration application. The housing assembly comprises an aluminium housing 1 to which two bimetallic connectors 2 are connected. In a first embodiment, a sleeve nut 3 or a similar structure may be provided for fixing the connectors 2 to the aluminium housing 1. The connectors 2 may be provided on opposite sides of the aluminium housing 1. The connectors 2 may be formed as a column and / or may be arranged coaxially with respect to each other.

[0030] The aluminum housing 1 may include a side flange portion 14. The side flange portion 14 is configured to connect a valve element, a sight glass or other components to the housing assembly. The side flange portion 14 may be connected to a side housing containing the valve element and / or other components. The side flange portion 14 may be arranged parallel to the axis of the connector 2. The side flange portion 14 may include an opening that communicates with the interior of the aluminum housing.

[0031] Figure 2A cross-sectional view of a first embodiment of a housing assembly is shown. The aluminum housing 1 comprises at least two fluid ports 11, 12. The fluid ports 11, 12 may communicate with a side flange portion 14. Each fluid port 11, 12 is fluidly connected to a bimetallic connector 2. The connector 2 contacts a connection portion 13 of the aluminum housing 1.

[0032] The connectors 2 each include a flange portion 23, which is an end portion of the connector 2 in contact with the aluminum housing 1. The connector 2 is pressed against the aluminum housing 1 via the flange portion 23 by means of the sleeve nut 3. The flange portion 23 may have the same outer diameter as the fluid ports 11, 12 at its contact surface.

[0033] The seal 24 may be disposed in a groove of the connection portion 13, thereby sealing the connection portion 13 relative to the flange portion 23. The seal 24 may be made of an elastic material and prevents leakage between the inside of the fluid ports 11, 12 and the outside of the structure.

[0034] There may be a narrow circumferential gap 15 between the side flange portion 14 and the sleeve nut 3. The width of the gap 15 may correspond to 50% to 200% of the wall thickness of the connector 2. The connector 2 may be formed as an identical part. In alternative embodiments, the fluid ports 11, 12 may not be arranged coaxially. For example, the fluid ports 11, 12 may be arranged at an angle between 0° and 180° to each other.

[0035] The connection portion 13 of the aluminum housing 1 is provided for connecting the aluminum housing 1 to the connector 2. The fluid ports 11, 12 may be at least partially arranged in the connection portion 13. The connection portion 13 of the first embodiment comprises a threaded portion for screwing the sleeve nut 3 onto the aluminum housing 1.

[0036] The connecting portions 13 may be oriented coaxially relative to each other. The connecting portions 13 may be oriented concentrically relative to their respective fluid ports 11, 12. The connecting portions 13 and / or the side flange portions 14 may protrude from a central structure of the aluminum housing 1 and / or may be integrally formed with the rest of the aluminum housing 1.

[0037] Figure 3 is a detailed cross-sectional view of a first embodiment of a housing assembly. A portion of the connector 2 is shown being fixed to the connection portion 13 by means of a sleeve nut 3. The sleeve nut 3 is screwed onto the threaded portion of the connection portion 13 and presses the connector 2 against the connection portion 13. A portion of the connector 2 is disposed between the sleeve nut 3 and the connection portion 13. Therefore, the flange portion 23 of the bimetallic connector 2 can be used to receive pressure from the sleeve nut 3, thereby forcing the connector 2 to abut against the connection portion 13 of the aluminum housing 1.

[0038] The connector 2 includes an inner copper layer 21 and an outer stainless steel layer 22. The inner diameter of the inner copper layer 21 may be equal to the inner diameter of the fluid ports 11, 12. The flange portion 23 of the connector may be arranged perpendicular to the columnar portion 24 of the connector 2.

[0039] The inner part of the bimetallic connector 2 is copper so that the housing assembly can be easily connected to, for example, copper pipes. These copper pipes are not shown in the figure. Copper pipes are usually used to fluidically connect the housing assembly to a certain heat exchange system.

[0040] Since the housing assembly comprises an aluminum housing 1, it is more difficult to provide a direct connection (eg, brazing) between the housing assembly and certain external copper conduits on site of the heat exchange system.

[0041] The presently described housing assembly including the connected bimetallic connector 2 allows the housing assembly to be fluidly connected to any suitable copper conduit by, for example, brazing the copper conduit to the inner copper layer 21 of the connector 2. This can be easily accomplished at any given location as it does not require complex joining methods.

[0042] Thus, standard methods for connecting copper parts to each other can be used to connect the aluminum housing 1 of the housing assembly currently described to the copper tube. Thus, the housing assembly currently described can be handled in the following manner, that is, as if it were made entirely of the more expensive brass / copper material, rather than the aluminum currently used.

[0043] Figure 4 1 is a perspective view of a second embodiment of a housing assembly. Compared to the first embodiment, no sleeve nut 3 is used to connect the connector 2 to the aluminum housing 1. Instead, a circumferential groove 16 is provided at the aluminum housing 1, into which the connector 2 can be partially inserted.

[0044] Figure 5 is a cross-sectional view of a second embodiment of the housing assembly. The connecting portion 13 of the second embodiment includes a circumferential groove 16, which is bounded by a radial outer wall 16'. The groove 16 may have an annular planar surface that contacts the connector 2 and extends in the radial direction. The groove 16 may include a welding portion and / or a brazing portion for connecting the connector 2 to the aluminum housing 1. The welding and / or brazing portion may extend in the circumferential direction of the groove 16. The radial, axial and circumferential directions may refer to the geometry of the columnar connector 2.

[0045] Figure 6is a detailed cross-sectional view of a second embodiment of the housing assembly. As can be seen more clearly than in the previous figure, the inner copper layer 21 is brazed and / or welded to the connection portion 13 of the aluminum housing 1. The connector 2 may include a flange portion 23 oriented in a radial direction of the connector. The inner copper layer 21 may be at least partially disposed on the flange portion 23 to contact the connection portion 13 of the aluminum housing 1. The connection portion 13 may be formed integrally with the housing 1.

[0046] The bimetallic connector 2 can be welded to the aluminum housing 1 in the following manner: furnace brazing, conveyor brazing, induction brazing, laser brazing, filler-free laser welding, filler-containing laser welding, stir welding, spin welding, ultrasonic welding, electromagnetic pulse welding, TIG welding and / or MIG welding. Typically, a single joining technique can be used. However, a combination of two or more of the above joining techniques can also be applied. The connection between the connector 2 and the connecting portion 13 can be provided along the flange portion 23 and the groove 16.

[0047] The outer stainless steel layer 22 covers all or most of the inner copper layer 21. The inner side of the stainless steel layer 22 may be connected to the outer side of the inner copper layer 21 via a material connection.

[0048] The invention also relates to a kit 1 comprising an aluminium housing, at least one bimetallic connector 2 and a sleeve nut 3 for a housing assembly according to at least claim 6. The kit can be provided with its components at least partially disconnected from one another. The user can connect the components according to existing requirements.

[0049] The presently described invention also covers embodiments in which features of different embodiments are combined with one another.

Claims

1. A housing assembly for a heat exchange system, the housing assembly comprising an aluminum housing (1) having at least two fluid ports (11, 12), wherein each fluid port (11, 12) is connected to a bimetallic connector (2), wherein the bimetallic connector (2) comprises an inner copper layer (21) and an outer stainless steel layer (22), and wherein the aluminum housing (1) comprises a connecting portion (13) for connecting the bimetallic connectors (2).

2. The housing assembly according to claim 1, characterized in that: These connection parts (13) include threaded parts, welded parts and / or brazed parts.

3. A housing assembly according to any one of the preceding claims, characterised in that The inner copper layer (21) is brazed and / or welded to the aluminum housing (1).

4. A housing assembly according to any one of the preceding claims, characterised in that The bimetallic connector (2) is welded to the aluminum housing (1) by furnace brazing, conveyor belt brazing, induction brazing, laser brazing, filler-free laser welding, filler-containing laser welding, stir welding, spin welding, ultrasonic welding, electromagnetic pulse welding, TIG welding and / or MIG welding.

5. A housing assembly according to any one of the preceding claims, characterised in that The outer stainless steel layer (22) covers all or most of the inner copper layer (21).

6. The housing assembly according to claim 2, characterized in that: A sleeve nut (3) is screwed onto the threaded portions of the connection portions (13), and a portion of the bimetallic connector (2) is disposed between the sleeve nut (3) and the connection portion (13).

7. A kit comprising an aluminium housing (1), at least one bimetallic connector (2) and a sleeve nut (3) for a housing assembly according to at least claim 6.

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