AN EVAPORATOR
AND
EVAPORATORPRODUCTIONMETHOD
This invention is related to an evaporator, which provides the heat transfer in the refrigeration systems and which includes a heater for the frost accumulation on it and production method thereof.
Heaters, in the form of tubes, inside which resistance wires are placed into the grooves, which are opened on the fins, for preventing the frost that will be accumulate during the operation of the evaporators with finned tubes that are used preferably in the refrigerators. These heaters cannot be effective in the melting of all of the frost accumulated on the evaporator.
Use of evaporators with finned tubes made of aluminum material are being preferred, due to advantages such as heat transfer, economy, and lightweight.
Welding is not used in the assembly of the tube fin onto the tube due to the material used and due to the ease of production. For this reason, the tube is formed in the form of a coil after making bends in the tube one after another.
Thus, consecutive straight tubes and tube bends are formed, which comprises number of passes and rows, in the form of an array. The evaporator is formed by inserting one or more tube fins onto the tubes from the tube bends preferably with equal spacing and in parallel line up to each other.
The increase of the area of contact of the tubes and the tube fins with the medium provides the increase in the cooling efficiency. Large numbers of tube fins, the contact of which with the tubes are increased, are being used due to this reason.
Frost accumulations are formed in between the tubes and the tube fins, during the
operation. Use of heaters are needed for the efficient functioning of the evaporator and for the melting of the frost accumulation..
An evaporator, which includes very thin fins and which includes heaters in the form of "U" in the lower parts of the fins, in the United States of America Patent No. 4580623 is defined.
The heaters that are inserted into the recesses on the fins for defrosting are defined in the French Patent No. 1422987.
The purpose of this invention is to develop an evaporator, which can melt the frost accumulated on the evaporator and to develop an economical and practical production method for this evaporator in a short period and by using small amount of energy.
An evaporator and the production method realized to attain the objective of this invention has been shown in the enclosed figures. Wherein:
Figure la - The perspective view of an evaporator with finned tubes, •
Figure lb - The perspective view of an evaporator with finned tubes, which includes more than one heater fins,
Figure 2 - The schematic view of a tube a tube fin, a heater and a heater fin,
Figure 3a - The front view of a heater fin,
Figure 3b - The side view of a heater fin,
Figure 4a - The side view of a heater fin, which has a circular in form and does not have an extension,
Figure 4b - The side view of a heater fin, in a triangular form,
Figure 4c - The side view of a heater fin, in a trapezoidal form,
Figure 4d - The side view of a curved heater fin, with single extension,
Figure 4e - The side view of a heater fin, in a rectangular form,
Figure 4f - The three dimensional view of a heater fin, with double extensions,
Figure 4g - The three dimensional view of a heater fin, with a twisted extension,
Figure 4h - The three dimensional view of a curved heater fin, with the form of a blade of a propeller,
Figure 4i - The three dimensional view of a curved heater fin, which has two twisted extensions,
Figure 4k - The side view of a curved heater fin, which has the same number of extensions as the heater recesses,
Figure 4m - The side view of a curved heater fin, which has less number of extensions than the heater recesses,
Figure 4n - The front view of a heater fin, with a triangular form, which has more number of extensions than the heater recesses,
Figure 5a - The upper schematic view of a fixture, which has more than one heater fin recesses, onto which heater fins are not placed,
Figure 5b - The side perspective view of a fixture, which has more than one heater fin recesses, onto which heater fins are not placed,
Figure 5c - The upper schematic view of a fixture onto which heater fins and heaters are placed
Figure 5d - The schematic view of the bending of the heater, onto which the heater fins are installed
The parts in the drawings are numbered as follows:
1. Evaporator
2. Tube
3. Tube fin
4. Heater
5. Heater fin
6. Extension
7. Heater recess
8. Catch of the heater recess
9. Heater installation recess
10. Tube recess
11. Fixture
12. Heater fin recess
One or more evaporators (1) are used in the domestic appliances, preferably in the refrigerators, to cool the medium that it is in contact with.
The evaporators (1) that are made with tubes with fins, which are preferably made of aluminum material, comprises one or more tubes (2), through which the cooling fluid passes and one or more tube fins (3) that makes the transfer of heat from the tube (2) in the medium to the cooling fluid.
The melting of the frost accumulated on the tubes (2) and the tube fins (3), while the refrigerator is in operation, and which prevent the flow of air on the evaporator
(1) and the transfer of heat of the tubes (2) and the tube fins (3) is provided by one or more heaters (4) that operate as much as required.
The tube fin (3), includes one or more tube recesses (10) into which the tube (2) is fitted and one or more heater installation recesses (9) to attach the heater.
The heater (4), includes one or more heater fins (5), attached onto the heater (4) and which provide the heat to be propagated into a wider area. Thus the melting of the frost accumulation in a shorter period is provided and less energy is consumed during the melting process. The heater fin (5) comprises one or more extensions (6) to enter among the tube fins (3) and at least one heater recess (7), to attach it onto the heater (4). The heater recess (7) includes one or more catches of the heater recess (8) at its tip parts, which provide the fixation of the heater fins (5) by installing it onto the heater (4).
The heater fin (5) has different forms and shapes, compared to the tube fin (3). For example curved form, circular form, triangular form, rectangular form (Figures 4a, 4b, 4c, 4d, and 4 e). In another embodiment of the invention, the heater fin (2) has extensions and surfaces in more than one planes. For example, these may be of the double extension form, twisted form, curved form and blade form of a propeller (Figures 4f, 4g, 4h and 4i). In another embodiment of the invention, the number of the extensions (6) is different than the number of the heater recesses (7). The number of the extensions (6), may the same with the heater recesses (7) (Figure 4k) or the number of the extensions (6) may be less than heater recesses (7) (Figure 4m) or the number of the extensions (6) may be more than the heater recesses (7) (Figure 4n).
Preferably, the heater fins (5) that have the same form are being used on the evaporator (1). In another embodiment of the invention, heater fins (5) that have different forms are being used, due to the reasons like the tube fin (3) form, the place that it will be attached on the heater (4), the flow of air that will be formed or the flow of air that it will be placed inside of, etc. In this embodiment, the extension (6) and/or the heater recess (7) may be of the same or different form (Figure 4m).
The fitting of the heater fin (5), which is the subject of the invention, onto the heater (4), is being accomplished by the evaporator production method.
In the evaporator (1) production method, the heater fins (5) are fitted onto the heater (4), preferably by the help of a fixture (11). The fixture (11), includes one or more heater fin recesses (12), into which the heater fins (5) are placed. The heater fins (5) may be located with equal spacing in a symmetrical manner to each other, as well as they may be located according to the place where the heates is used.
The heater (4) of which its bending have been made is inserted into the heater recesses (7), after the heater fins (5) are placed in a row, as desired, onto the fixture (11). The catches of the heater recesses (8) that have bendings preferably in different directions provide the heater (4) not to come off loose from the heater recesses (7). The heater (4), which is pressed onto the catches of the heater recesses (8) and the heater fin (5), may easily enter the heater recesses (7). But, when the heater (4) is to be pulled out, the catches of the heater recesses (8) prevent the heater fins (5) to leave the heater (4) by acting as a lock. In order heater (4), is being bent from the bending axis and/or axes towards each other, by taking off the heater (4), which is fitted by heather fins (5) from the fixture (11).
Thus, the extensions (6) remain in such a manner that they face the internal side of coil pile of the heater (4).
A tube (2) coil is formed, which comprises of consecutive straight tubes and tube bends, formed by a number of passes and rows, after the consecutive bends of the tube (2), apart from the heater (4) coil pile. The tube (2) is placed in the recesses, on tube fins (3), which are parallel to each other and preferably with equal spacing, by the help of the coil tube bends.
The assembling of the evaporator (1) with heater (4) is completed without welding, by installing the heater (4) coil pile onto the tube recesses (9).
Since the heater fin (5) is located between the tube fins (3) and inside the airflow, which is formed between the tube fins (3), a turbulent flow is formed, especially when the heater (4) is in operation the thermal performance of the evaporator (1) is thus improved.