Condenser for a Refrigerator

Abstract

the present invention a condenser comprises an aluminum tube. The aluminum tube comprises a first interior surface in thermal communication with a first fluid and a second exterior surface in thermal communication with a second fluid. In an alternate embodiment a refrigerator comprises a condenser. The condenser further comprises an aluminum tube. The aluminum tube has a first interior surface in thermal communication with a first fluid and a second exterior surface in thermal communication with a second fluid. Wherein the first surface further comprises internal fins and the second surface further comprises external fins.

Description

BACKGROUND OF THE INVENTION

[0001]This invention relates generally to heat exchangers for appliances, and more particularly, to an aluminum heat exchanger for a refrigerator.

[0002]Known household appliances are available in various platforms having different structural features, operational features, and controls. For example, known refrigerator platforms include side-by-side single and double fresh food and freezer compartments, and vertically oriented fresh food and freezer compartments including top mounted freezer compartments, and bottom mounted freezer compartments.

[0003]As well known to those skilled in the art, various types of refrigerators are used to freeze or refrigerate foods. FIG. 1 is a longitudinal sectional view of a general refrigerator 100. The refrigerator 100 comprises a housing 10 defined by an internal receiving space divided into a freezing chamber 101 and a refrigerator chamber 102, freezing and refrigerating chamber doors 12 and 13 respectively, are mounted to one side of the housing 10 for opening/closing the freezing chamber 101 and refrigerating chamber 102. A number of devices are used, including a compressor 20, a condenser 30, an expander (not shown) and an evaporator 40 for generating cold air in a cooling cycle.

[0004]Describing the operation of the refrigerator as set forth above, gaseous refrigerant in a low temperature and pressure state is compressed into a high temperature and pressure by the compressor 20. The compressed gaseous refrigerant at high temperature and pressure is converted into a high pressure liquid as it is cooled and condensed while passing through the condenser 30. The high pressure liquid refrigerant experiences a reduction in temperature and pressure while passing through the expander (not shown). Thus, the refrigerant is transformed into a low temperature and pressure gas by absorbing heat from surrounding members as it passes there through.

[0005]Then, air cooled by the evaporator 40 is circulated into the freezing chamber 101 primarily by operation of a fan 50 installed in an evaporator room 103. This circulation lowers the temperature of the freezing chamber 101 and the refrigerating chamber 102.

[0006]The condenser 30 is generally used as a fin tube-type condenser comprising a refrigerant pipe 32 and a number of heat-radiating fins 34. The refrigerant pipe 32 is made of metal and continuously bent into a multi-layered, serpentine structure and configuration. The heat-radiating fins 34 are arranged in a spaced parallel configuration. The fins are substantially perpendicular to pipe 32 and are attached to the refrigerant pipe 32 via welding, and mounted in the shape of a thin panel apparently crossing said bent refrigerant pipe 32.

[0007]It is the objective of the refrigeration industry world-wide to develop smaller, more energy-efficient heat exchangers in order to reduce material and energy costs. Aluminum is preferred for its performance and manufacturability. However, aluminum is susceptible to corrosion and therefore does not meet life requirements for the condenser application in a household refrigerator.

SUMMARY OF THE INVENTION

[0008]According to an aspect of the present invention a condenser comprises an aluminum tube. The aluminum tube comprises a first interior surface in thermal communication with a first fluid and a second exterior surface in thermal communication with a second fluid.

[0009]In an alternate embodiment a refrigerator comprises a condenser. The condenser further comprises an aluminum tube. The aluminum tube has a first interior surface in thermal communication with a first fluid and a second exterior surface in thermal communication with a second fluid. Wherein the first surface further comprises internal fins and the second surface further comprises external fins.

[0010]In another alternate embodiment a refrigerator comprises a condenser. The condenser further comprises an aluminum tube. The aluminum tube has a first interior surface in thermal communication with a first fluid and a second exterior surface in thermal communication with a second fluid.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a longitudinal sectional view of a prior art refrigerator.

[0012]FIG. 2 is a perspective view of a condenser of the refrigerator of FIG. 1 according to an aspect of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0013]It is contemplated that the teaching of the description set forth below is applicable to all types of refrigeration units, including but not limited to household refrigerators but include a standalone refrigeration unit or may be connected to other appliances requiring heat exchange. The present invention is therefore not intended to be limited to any particular refrigeration device.

[0014]As indicated hereinabove, FIG. 1 illustrates a top mount refrigerator 100 including a refrigerator chamber 102 and freezer chamber 101. Freezing chamber 101 and refrigerator chamber 102 are arranged in a top mount configuration where the freezing chamber 101 is above the refrigeration chamber 102. The refrigeration chamber is shown with door 13. However, a more than one door may be used in a French door configuration. Door 12 closes freezer compartment 101.

[0015]In accordance with known refrigerators, refrigerator 100 also includes a machinery compartment that at least partially contains components for executing a known vapor compression cycle for cooling air in the compartments. The components include a compressor 20, a condenser 30, an expansion device (not shown), and an evaporator 40 connected in series and charged with a refrigerant. The evaporator is a type of heat exchanger that transfers heat from air passing over the evaporator to a refrigerant flowing through the evaporator, thereby causing the refrigerant to vaporize. The cooled air is used to refrigerate one or more refrigeration chamber or freezing chamber via fans 103. Collectively, the vapor compression cycle components in a refrigeration circuit, associated fans, and associated compartments are referred to herein as a sealed system. The condenser 30 is traditionally constructed in a tube fin configuration from a ferrous metal. The construction of the sealed system is well known and therefore not described in detail herein, and the sealed system is operable to force cold air through the refrigerator 100.

[0016]The condenser 300 of the present invention is essentially a heat exchanger. The heat exchange is made up of heat exchanger tubes 301. A heat exchanger tube 301 is used in a process that transfers heat between a first fluid inside the heat exchanger tube 301 and a second fluid outside of the heat exchanger tube 301. The efficiency of heat transfer between the first fluid and the second fluid may be a complicated function that depends on a number of variables such as the characteristics of the fluids, on the characteristics of the heat exchanger tube 301, and on the characteristics of fluid movement relative to the heat exchanger tube 301. The term "fluid" refers to a liquid, a gas, or a combination of a liquid and a gas.

[0017]Aluminum is used in heat exchangers of scale where tube walls and fin thickness can be such that oxidization of the aluminum does not result in failure. Aluminum oxidizes by pitting. In thin walled aluminum structures, used in household refrigeration, the pitting causes the heat exchanger to leak refrigerant.

[0018]FIG. 2 illustrates an exemplary condenser 300 in accordance with one embodiment of the present invention. Condenser 300 is constructed from aluminum providing improved heat transfer between the refrigerant and the ambient air. The heat exchanger 300 comprises a flat tube 301 formed in a zig-zag or serpentine configuration made of aluminum. Corrugated fins 302 made of aluminum are arranged between and joined to the adjacent straight tubular portions of the tube 301. A joint member 303 also made of aluminum is joined to each end of the tube 301. Each corrugated fin 302 is joined to the tube 301 by fillets, which are substantially comprised of zinc.

[0019]The tube 301 and the fin 302 are each made of a material nobler than the fillet by at least 0.325 V in terms of potential. An example of a useful material which is nobler than the fillet by at least 0.325 V in terms of potential is an aluminum alloy comprising 0.1 to 1.0 wt. %, preferably 0.2 to 0.5 wt. %, of copper, and the balance being aluminum and inevitable impurities. Also useful is an aluminum alloy comprising 0.1 to 1.0 wt. %, preferably 0.2 to 0.5 wt. %, of copper, 0.1 to 1.0 wt. %, preferably 0.2 to 0.5 wt. %, of manganese, and the balance of aluminum and inevitable impurities. Also useful is an aluminum alloy comprising 0.1 to 1.0 wt. %, preferably 0.2 to 0.5 wt. %, of copper, 0.1 to 1.0 wt. %, preferably 0.2 to 0.5 wt. %, of manganese, at least one of titanium, boron, chromium and zirconium in an amount of 0.01 to 0.1 wt. %, 0.01 to 0.1 wt. %, 0.01 to 0.5 wt. % and 0.01 to 0.5 wt. % respectively, and the balance of aluminum and inevitable impurities. It is especially desirable that the tube 301 and the fin 302 be made of a material nobler than the fillet by at least 0.375 V in terms of potential. Although not limitative, the tube 301 and the fin 302 are preferably made of the same material.

[0020]After the tube 301 and fin 302 are joined, the condenser 300 is coated with an anti-corrosion material. Non-limiting examples of anti-corrosive material include polyurethane, galvalume or mixed zinc/aluminum flakes.

[0021]The use of high performance aluminum with enhanced surface tubes in the heat exchangers of a refrigerator will contribute significantly in increased energy efficiency as well as reduction in the size of the condenser, and a corresponding reduction in the overall cost of refrigerant and related equipment.

[0022]While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.

Claims

1. A condenser comprising:an aluminum tube comprising:a first surface in thermal communication with a first fluid; anda second surface in thermal communication with a second fluid.

2. The condenser according to claim 1, wherein the first surface further comprises internal fins.

3. The condenser according to claim 1, wherein the second surface further comprises external fins.

4. The condenser according to claim 2, wherein the second surface further comprises external fins.

5. The condenser according to claim 1, wherein the second surface further comprises a non-corrosive coating.

6. A refrigerator comprising:a condenser, wherein the condenser comprises an aluminum tube, the aluminum tube further comprising:a first surface in thermal communication with a first fluid; anda second surface in thermal communication with a second fluid.

7. The refrigerator according to claim 6, wherein the first surface further comprises internal fins.

8. The refrigerator according to claim 6, wherein the second surface further comprises external fins.

9. The condenser according to claim 7, wherein the second surface further comprises external fins.

10. The condenser according to claim 6, wherein the second surface further comprises a non-corrosive coating.

11. A refrigerator comprising:a condenser, wherein the condenser comprises an aluminum tube, the aluminum tube further comprising:a first interior surface in thermal communication with a first fluid; anda second exterior surface in thermal communication with a second fluid;wherein the first surface further comprises internal fins and the second surface further comprises external fins.

12. The condenser according to claim 11, wherein the second surface further comprises a non-corrosive coating.

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