REPLACEABLE MELTING FURNACE BODY AND METHOD FOR PRODUCING THE SAME

Abstract

 A replaceable melting furnace (2) includes a replaceable furnace body (21) having a main body (211) that has an open end (213) and that defines a receiving space (214) therein, and a partition plate (212). The receiving space (214) is divided into an upper space (215) and a lower space (216). The partition plate (212) extends from the open end (213) into the upper space (215) to divide the upper space (215) into first and second subspaces (2151, 2152) that are fluidly communicated with each other through the lower space (216). A method for producing the aforesaid replaceable melting furnace (2) is also disclosed.

Description

[0001] This invention relates to a melting furnace and a method for producing the same, more particularly to a replaceable melting furnace adapted for melting a metal therein.

[0002] Taiwanese Patent No. I280166 discloses a conventional melting furnace used in a die casting machine. The melting furnace is adapted for melting a metal and holding the molten metal. The melting furnace has to be replaced when a surface of the melting furnace that contacts the molten metal is damaged by the molten metal. Therefore, the maintenance cost is relatively high.

[0003] Referring to Fig. 1, another conventional melting furnace 9 is shown to include a metal housing 91, a thermal insulating layer 92 disposed in the housing 91, a graphite crucible 93 disposed in the thermal insulating layer 92, and a heating module 94 disposed between the graphite crucible 93 and the thermal insulating layer 92. When the melting furnace 9 is operated, the graphite crucible 93 is heated by the heating module 94 so as to melt aluminum ingots (not shown) inside the graphite crucible 93 to obtain a molten aluminum. In this case, the graphite crucible 93 can be independently replaced when damaged, and there is no need to replace the entire melting furnace 9.

[0004] Moreover, when the melting furnace 9 is not operated and the metal is cooled down and is still disposed in the graphite crucible 93, the graphite crucible 93 is easily damaged due to different thermal expansion coefficients of the graphite crucible 93 and the metal. Furthermore, the graphite crucible 93 will be gradually eroded by the molten aluminum, and has to be regularly replaced at intervals of about six to eight months, thereby resulting in an increase in maintenance costs.

[0005] In addition, the aluminum ingots usually contain impurities. When the aluminum ingots are melted in the graphite crucible 93, the impurities will float on a surface of the molten aluminum. When the molten aluminum is scooped out of the graphite crucible 93 for subsequent use, the molten aluminum containing the impurities would adversely affect the quality and the yield of a product made from the molten aluminum.

[0006] Therefore, the object of the present invention is to provide a replaceable melting furnace that can overcome at least one of the aforesaid drawbacks of the prior art.

[0007] According to one aspect of the present invention, there is provided a replaceable melting furnace that includes a replaceable furnace body including a main body and a partition plate. The main body has an open end and defines a receiving space therein. The receiving space is divided into an upper space and a lower space. The partition plate extends from the open end into the upper space to divide the upper space into first and second subspaces that are fluidly communicated with each other through the lower space.

[0008] According to another aspect of the present invention, there is provided a method for producing the aforesaid replaceable melting furnace that includes the steps of:

(a) preparing a mold unit that includes a lower mold having an open end and defining an accommodating space therein, and an upper mold including a mounting member and an extending member that is connected to the mounting member, the mounting member having an inlet, the extending member having an upper portion that is formed with a groove to divide the upper portion into two parts and that is intimately connected to the mounting member, the mounting member being connected to the open end of the lower mold and the extending member extending into the accommodating space such that a mold cavity is formed between the lower mold and the extending member of the upper mold;

(b) filling a refractory material in the groove and the mold cavity through the inlet of the mounting member of the upper mold, followed by solidifying the refractory material to form the replaceable furnace body; and

(c) sintering the replaceable furnace body.

[0009] Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment of this invention, with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of a conventional melting furnace;

Fig. 2 is an assembled partly cutaway perspective view of the preferred embodiment of a replaceable melting furnace according to this invention;

Fig. 3 is an exploded perspective view of the preferred embodiment;

Fig. 4 is an enlarged perspective view showing a replaceable furnace body of the preferred embodiment;

Fig. 5 is a flowchart of the preferred embodiment of a method for producing the replaceable melting furnace according to this invention; and

Fig. 6 is an exploded perspective view of a mold unit used in the method of the preferred embodiment.

[0010] Figs. 2, 3 and 4 show the preferred embodiment of a replaceable melting furnace 2 according to the present invention. The replaceable melting furnace 2 is adapted for melting a metal and holding the molten metal therein, and includes a replaceable furnace body 21, a housing 22 and a thermal insulating layer 23.

[0011] The replaceable furnace body 21 includes a main body 211 having an open end 213 and defining a receiving space 214 therein, and a partition plate 212. The receiving space 214 is divided into an upper space 215 and a lower space 216. The partition plate 212 extends from the open end 213 into the upper space 215 to divide the upper space 215 into first and second subspaces 2151, 2152 that are fluidly communicated with each other through the lower space 216. The replaceable furnace body 21 is made of a castable refractory material selected from the group consisting of clay, aluminum oxide (Al₂O₃), and the combination thereof. Preferably, the partition plate 212 has a vertical height (H1) that is about one third of a maximum vertical height (H2) of the replaceable furnace body 21 (see Fig. 4).

[0012] The housing 22 is made of metal and defines a recess 221 for accommodating the replaceable furnace body 21. The housing 22 can be made by, for example, machine work.

[0013] The thermal insulating layer 23 is disposed between the housing 22 and the replaceable furnace body 21. The replaceable furnace body 21 is detachably connected to the thermal insulating layer 23. In this embodiment, the thermal insulating layer 23 is made of a fiberglass insulating material. It is noted that the thermal insulating layer 23 may be omitted depending on actual requirements. In such case, the replaceable furnace body 21 is detachably connected to the housing 22.

[0014] Referring to Figs. 5 and 6, the preferred embodiment of a method for producing the aforesaid replaceable melting furnace 2 according to the present invention includes the following steps of:

(a) preparing a mold unit 4 that includes a lower mold 41 having an open end 411 and defining an accommodating space 412 therein, and an upper mold 42 including a mounting member 421 and an extending member 422 that is connected to the mounting member 421, the mounting member 421 having an inlet 4211, the extending member 422 having an upper portion 423 that is formed with a groove 424 to divide the upper portion 423 into two parts 425 and that is intimately connected to the mounting member 421, the mounting member 421 being connected to the open end 411 of the lower mold 41 and the extending member 422 extending into the accommodating space 412 such that a mold cavity is formed between the lower mold 41 and the extending member 422 of the upper mold 42;

(b) filling a refractory material in the groove 424 and the mold cavity through the inlet 4211 of the mounting member 421 of the upper mold 42, followed by solidifying the refractory material to form the replaceable furnace body 21;

(c) sintering the replaceable furnace body 21; and

(d) disposing the replaceable furnace body 21 into a housing 22 and disposing a thermal insulating layer 23 between the replaceable furnace body 21 and the housing 22 in such a manner that the replaceable furnace body 21 is detachably connected to the thermal insulating layer 23.

[0015] In step (a), each of the lower mold 41 and the extending member 422 may be made of several components that are designed to be easily assembled and disassembled. The groove 424 of the upper portion 423 of the extending member 422 corresponds in position to the partition plate 212 of the replaceable furnace body 21. The mold cavity formed between the lower mold 41 and the extending member 422 of the upper mold 42 corresponds in position to the main body 211 of the replaceable furnace body 21. In this embodiment, the mounting member 421 and the extending member 422 of the upper mold 42 are detachably and intimately connected to each other. However, in other embodiments, the mounting member 421 and the extending member 422 of the upper mold 42 can be formed as one piece. In this embodiment, the extending member 422 is made of styrofoam.

[0016] In this embodiment, the refractory material is naturally solidified to form the replaceable furnace body 21 without using a machine tool.

[0017] Preferably, step (c) is conducted at 600 °C for 24 hours.

[0018] It is noted that the thermal insulating layer 23 may be omitted depending on actual requirements. In this case, in step (d), the replaceable furnace body 21 is disposed into a housing 22 in such a manner that the replaceable furnace body 21 is detachably connected to the housing 22.

[0019] The replaceable melting furnace 2 can be used in a molten metal supply device, such as a device disclosed in Taiwanese Utility Model No. M444231. In use, in the beginning, metal ingots (such as aluminum ingots) are placed into the replaceable furnace body 21 and melted to form a molten metal liquid with a liquid surface higher than a lower end of the partition plate 212. To be specific, the liquid surface is divided into two sub-surfaces in the first and second sub-spaces 2151, 2152 of the upper space 215 of the receiving space 214. Impurities contained in the metal ingots would float on the liquid sub-surfaces. Preferably, the impurities floating on the second sub-space 2152 is removed. Then, additional metal ingots are gradually placed into the replaceable furnace body 21 through the first sub-space 2151 such that the metal ingots gradually sink into the first sub-space 2151 and are mainly melted in the first sub-space 2151. As such, the impurities of the metal ingots mainly float on the liquid sub-surface in the first sub-space 2151. Therefore, the amount of impurities in the second sub-space 2152 can be greatly reduced. The molten metal with relatively high purity in the second sub-surface 2152 can be taken out from the replaceable melting furnace 2 for subsequent use.

[0020] Therefore, with the partition plate 212, the purity of the molten metal taken out from the second sub-space 2152 of the replaceable furnace body 21 can be improved.

[0021] Moreover, the replaceable melting furnace 2 according to this invention has a longer service life than the conventional melting furnace since the replaceable furnace body 21 is made of the refractory material and does not need to be replaced frequently, thereby reducing maintenance costs.

[0022] In addition, since the replaceable furnace body 21 is detachably connected to the housing 22/the thermal insulating layer 23, when the replaceable furnace body 21 is damaged, only the replaceable furnace body 21 needs to be replaced instead of the entire replaceable melting furnace 2.

Claims

1. A replaceable melting furnace (2) for melting a metal therein, said replaceable melting furnace (2) being characterized by:

a replaceable furnace body (21) having:

a main body (211) that has an open end (213) and that defines a receiving space (214) therein, said receiving space (214) being divided into an upper space (215) and a lower space (216); and

a partition plate (212) that extends from said open end (213) into said upper space (215) to divide said upper space (215) into first and second subspaces (2151, 2152) that are fluidly communicated with each other through said lower space (216).

2. The replaceable melting furnace (2) as claimed in claim 1, characterized in that said replaceable furnace body (21) is made of a castable refractory materal.

3. The replaceable melting furnace (2) as claimed in claim 1, further characterized by a housing (22) made of metal and defining a recess (221) for accommodating said replaceable furnace body (21), said replaceable furnace body (21) being detachably connected to said housing (22).

4. The replaceable melting furnace (2) as claimed in claim 1, further characterized by a housing (22) made of metal and a thermal insulating layer (23) disposed between said housing (22) and said replaceable furnace body (21), said replaceable furnace body (21) being detachably connected to said thermal insulating layer (23).

5. The replaceable melting furnace (2) as claimed in claim 4, characterized in that the thermal insulating layer (23) is made of a fiberglass insulating material.

6. A method for producing a replaceable melting furnace (2) as claimed in claim 1, characterized by the steps of:

(a) preparing a mold unit (4) that includes a lower mold (41) having an open end (411) and defining an accommodating space (412) therein, and an upper mold (42) including a mounting member (421) and an extending member (422) that is connected to the mounting member (421), the mounting member (421) having an inlet (4211), the extending member (422) having an upper portion (423) that is formed with a groove (424) to divide the upper portion (423) into two parts (425) and that is intimately connected to the mounting member (421), the mounting member (421) being connected to the open end (411) of the lower mold (41) and the extending member (422) extending into the accommodating space (412) such that a mold cavity is formed between the lower mold (41) and the extending member (422) of the upper mold (42);

(b) filling a refractory material in the groove (424) and the mold cavity through the inlet (4211) of the mounting member (421) of the upper mold (42), followed by solidifying the refractory material to form the replaceable furnace body (21); and

(c)sintering the replaceable furnace body (21).

7. The method as claimed in claim 6, characterized in that, in step (b), the refractory material is a castable refractory material.

8. The method as claimed in claim 6, characterized in that step (c) is conducted at 600 °C for 24 hours.

9. The method as claimed in claim 6, characterized by, after step (c), a step (d) of disposing the replaceable furnace body (21) into a housing (22) in such a manner that the replaceable furnace body (21) is detachably connected to the housing (22).

10. The method as claimed in claim 6, characterized by, after step (c), a step (d) of disposing the replaceable furnace body (21) into a housing (22) and disposing a thermal insulating layer (23) between the replaceable furnace body (21) and the housing (22) in such a manner that the replaceable furnace body (21) is detachably connected to the thermal insulating layer (23).

Drawing