KR100558445B1 - A continuous sintering furnace having pulse type gas inlet system - Google Patents

Abstract

The present invention provides a furnace body having an inner passage, a heating element for providing a heat source to the inner passage, a side air supply unit for supplying an atmosphere gas from the side surface of the furnace body to the center portion, and a gas for discharging the furnace body upwards. A firing furnace for firing a ceramic product having a conveying part for transporting an accommodating part in which the upper exhaust port and the unbaked ceramic product is loaded in one direction, the side of which is parallel to the main gas flow which supplies the atmospheric gas to the center of the inner space through the side air supply. A pulse air supply mechanism provided near the side air supply mechanism so as to form a pulse gas flow in a side of the housing portion at the left and right sides of the furnace body; And a pulse gas supply line for supplying an atmosphere gas to the pulse supply mechanism and having a control valve installed in the middle of the length of the control valve for controlling supply of pulse gas injected into the side of the accommodating portion.

According to the present invention, the flow rate of the atmospheric gas is instantaneously increased to the left and right sides of the storage unit passing through the debinding zone to improve gas flow in the furnace, and the gas stagnant zone is eliminated to uniformly maintain the gas atmosphere in the furnace. It is possible to obtain the effect of maintaining and increasing the exhaust removal rate of the debinder gas.

Firing Furnace, Ceramic Products, Atmospheric Gas, Side Supply, Upper Exhaust, Pulse Supply

Description

Continuous firing furnace with intermittent air supply system {A CONTINUOUS SINTERING FURNACE HAVING PULSE TYPE GAS INLET SYSTEM}             

Figure 1 (a) is a cross-sectional view showing the internal structure of a typical continuous firing furnace.

1 (b) is a firing profile in a typical continuous firing furnace.

2 is a configuration diagram of a typical continuous firing furnace.

3 is a longitudinal cross-sectional view of a continuous firing furnace having an intermittent air supply system according to the present invention.

4 is a height sectional view of a continuous firing furnace having an intermittent air supply system according to the present invention.

Figure 5 (a) is a block diagram of a continuous firing furnace having an intermittent air supply system according to the present invention.

Figure 5 (b) is a graph showing the timing of the left and right pulse pipe in the continuous firing furnace having an intermittent air supply system according to the present invention.

Explanation of symbols on the main parts of the drawings

2: main body 3: internal passage

4: heating element 5: side air supply

6: upper exhaust port 7: housing

110: pulse supply mechanism 111,112: left and right pulse pipe

120: pulse gas supply line 121,122: control valve

121a, 122b: Timer 100: Firing Furnace

The present invention relates to a sintering furnace, and more particularly, to supply the atmosphere gas evenly to both sides of the housing portion in which the ceramic product to be fired is loaded, and at the same time to the left and right side of the housing portion passing through the binder removal area Momentary increase or decrease to improve the gas flow in the furnace, eliminate the gas congestion zone to maintain the gas atmosphere in the furnace uniformly, and improve the exhaust removal rate of debinder gas. It relates to a continuous firing furnace having.

In general, ceramic electronic components and other ceramic products using ceramics such as laminated ceramic capacitors, varistors, ferrites, piezo-electric bodies, etc., and other ceramic products are formed by molding ceramic raw materials into a predetermined shape. It is manufactured by manufacturing and baking the said molded object.

The effective removal of binders used during molding during the firing process of ceramic products has emerged as an important process variable to control the quality characteristics, and the removal of these binders is carried out in an independent debinder process called calcining or in a plastic elevated temperature profile. This heat treatment process is performed in a tunnel type continuous firing furnace.

Figure 1 (a) is a cross-sectional view showing the internal structure of a typical tunnel continuous firing furnace, Figure 1 (b) is a plastic profile in a typical tunnel continuous firing furnace, Figure 2 is a configuration diagram of a typical tunnel continuous firing furnace.

1 and 2, the conventional firing furnace 1 is a furnace body 2 having a tunnel-type inner passage 3 of a predetermined length from the inlet to the outlet, and a heating element for providing a heat source to the inner passage 3, as shown in Figs. (4), side air supply mechanisms 5 having air supply pipes 5a on the left and right sides of the furnace body 2, and supplying atmospheric gas from the side to the center portion, and exhaust pipes on the upper part of the inner passage 3; (6a) and an upper exhaust pipe (6) for discharging gas in the furnace to the outside, and a receiving portion (7) in which sheets (not shown) on which ceramic products to be baked are placed are stacked in multiple stages.

In FIG. 2, reference numeral 6b is a valve provided in the exhaust pipe 6a, 6c is an exhaust fan, 7a is a support plate, 8 is a pressure gauge for measuring the pressure inside the furnace body, and 9 is the air supply 5) Main gas supply line to supply atmospheric gas.

Accordingly, in the ceramic product loaded on the accommodating part 7, the supporting plate 7a is sequentially transferred through the inner passage 3 of the furnace body 2 by a conveying part such as a pusher. The conveyed ceramic products are gradually removed from the binder area (A) for removing the binder as the furnace temperature is gradually increased, the firing area (B) where the ceramic product is fired while the elevated temperature is kept constant, and the furnace temperature is gradually lowered. It is fired while continuously passing through the cooling zone (C) for cooling the ceramic product.

However, in the case of the conventional kiln 1, since the side gas is supplied from the side into the furnace body 2 from the side, and the gas flow of exhausting the atmosphere gas to the upper portion of the furnace body 2 is constant in one direction only. In the central portion of the housing 7 in which the ceramic product is loaded, a dead zone, which is a region in which gas flow is stagnant, is locally generated, thereby causing a spatial dispersion in the firing furnace 1.

In this case, the debinding region (A) is an essential process of thermally decomposing or sintering an organic binder contained in a ceramic product, and debinding gas such as carbon monoxide / carbon dioxide is generated, and the debinding gas is supplied to the atmosphere gas. In this case, it should be discharged from the inside of the ceramic ceramic product to the outside by the exhaust flow.

As a result, when a dead zone, which is a gas stagnation region, is formed in the vicinity of the accommodating portion 7 where the ceramic product is loaded, the debinder gas generated inside the ceramic product during the debinder process escapes to the outside of the product and is properly brought into the furnace. Because it is not exhausted, localized plastic non-uniformity may occur in the firing zone (B) due to stagnation or concentration of debinding gas, and it may cause cracking or peeling of ceramic products and cause product defects. It was.

Accordingly, the present invention has been made to solve the above problems, the object of the furnace is to increase or decrease the supply of the atmospheric gas on the left and right sides of the furnace body during the constant supply of the atmospheric gas to the furnace side by the inner furnace The present invention aims to provide a continuous firing furnace having an intermittent air supply system that can increase the gas flow in the gas stream, remove the region where the gas is stagnated by generating vortices, and increase the exhaust efficiency of the debinder gas.

As a technical means for achieving the above object, the present invention

A furnace body having an inner passage, a heating element for providing a heat source to the inner passage, a side air supply for supplying atmospheric gas from the side of the furnace body to the center portion, an upper exhaust pipe for discharging the gas of the furnace body to the top; In the firing furnace for firing the ceramic product having a conveying section for transporting in one direction the receiving portion in which the unbaked ceramic product is loaded,

In the vicinity of the side air supply structure to form a pulse gas flow in parallel with the main gas flow for supplying the atmosphere gas to the central portion of the inner passage through the side air supply to the side of the receiving portion from the left and right sides of the furnace body. A pulse supply mechanism installed;

An intermittent air supply system, comprising: a pulse gas supply line for supplying an atmosphere gas to the pulse supply mechanism, and having a control valve installed in the middle of the length of the control valve for controlling supply of pulse gas injected to the side of the accommodating part; By providing a continuous firing furnace having a.

Preferably, the pulse supply mechanism is provided at a predetermined interval in the binder removal area.

Preferably, the pulse supply mechanism is composed of a plurality of left and right pulse pipes disposed horizontally on both the left and right sides of the furnace main body so that the front and rear ends facing the left and right sides of the housing part are exposed to the inner passage.

More preferably, the plurality of left and right pulse pipes vertically aligned to the left and right sides of the furnace body are arranged at different heights.

More preferably, the control valve is provided with a timer for controlling the on / off at regular intervals so that the pulsed gas from the left and right pulse pipes are not simultaneously supplied into the inner passage.

More preferably, the left and right pulse pipes are equipped with a heater to heat up the pulsed gas supplied into the inner passage.

Preferably, the pulse gas supply line is a branching line branched from the main gas supply line for supplying atmospheric gas to the side air supply.

Preferably, the pulse gas supply line is an independent line for separately supplying pulsed gas into the inner passage.

Hereinafter, the present invention will be described in more detail.

Figure 3 is a longitudinal cross-sectional view of the continuous firing furnace having an intermittent air supply system according to the present invention, Figure 4 is a longitudinal cross-sectional view of the continuous firing furnace having an intermittent air supply system according to the present invention, Figure 5 (a) is the present invention Figure 5 is a block diagram of a continuous firing furnace having an intermittent air supply system according to the present invention, Figure 5 (b) is a graph showing when the left and right pulse pipe is operated in the continuous firing furnace having an intermittent air supply system according to the present invention.

The firing furnace 100 of the present invention has a furnace body 2 having an inner passage 3 as in the prior art, a heating element 4 providing a heat source, and a side surface for supplying atmospheric gas from the side surface of the furnace body 2. And an air supply port (5), an upper exhaust port (6) for discharging the gas in the inner passage (3) to the upper part, and a conveying part for transporting the accommodating part (7) on which the unbaked ceramic product is loaded. Detailed description thereof will be omitted, and the same reference numerals will be given.

The kiln 100 shown in FIGS. 3 to 5 smoothly exhausts unnecessary gas in a reducing atmosphere such as carbon monoxide / carbon dioxide generated in the debinding zone A during the debinding process of removing the binder component included in the ceramic product. The firing furnace 100 is composed of a pulse supply mechanism 110 and a pulse supply line 120 by instantaneously increasing the supply air flow rate from the side of the furnace main body 2 to be made.

That is, the pulse supply mechanism 110 is provided with a side air supply mechanism 5 at regular intervals in the longitudinal direction on both the left and right sides, and a main body having an upper exhaust hole 6 at a predetermined distance in the longitudinal direction on the upper surface. The side air supply mechanism 5 is formed in parallel with the main gas flow which supplies atmospheric gas to the center portion of the inner passage 3 through the side air supply mechanism 5 at the left and right sides of the air passage 2, and forms a rapid pulse gas flow. It is installed in the neighborhood of).

The pulse supply mechanism 110 is provided in plural intervals at left and right sides of the furnace body corresponding to the debinder area A in which the furnace temperature is increased to remove the binder component contained in the ceramic product.

In addition, the pulse supply mechanism 110 of the furnace body 2 so that the front and rear ends of the accommodating part 7 facing each other are exposed into the inner passage 3 through which the accommodating part 7 is conveyed. It consists of a plurality of left and right pulse pipes 111 and 112 arranged horizontally on both the left and right sides.

The accommodating part 7 is composed of a sheet on which a plurality of ceramic products to be fired is placed, and a plurality of sheets are stacked vertically, and a supporting plate 7a is conveyed to the outlet side along the inner passage 3 by a conveying part. .

Here, the plurality of vertically arranged left pulse pipes 111 and right pulse pipes 112 which are installed at regular positions at predetermined intervals on the left and right sides of the furnace body 3 are pulsed toward the center of the inner passage 3. When the gas is supplied, it is preferable that the gas supplied in the direction facing each other is disposed at different heights so as to cancel each other so as to cancel each other so as not to lower the injection speed of the pulsed gas.

Accordingly, the pulsed gas supplied from the left pulse pipe 111 of the furnace main body is supplied to the atmosphere gas of a sudden gas flow from the left side to the right side of the accommodating part, and the pulsed gas supplied from the right pulse pipe 112 is By supplying the atmosphere gas with a sudden gas flow from the right side to the left side of the accommodating part 7, vortices are formed inside and outside the accommodating part 7, thereby preventing the dead zone, which is a gas stagnation region, from occurring. It can be.

In addition, the left and right pulse pipes 111 and 112 debind the atmospheric gas which is the pulse gas supplied into the inner passage 3 of the furnace body 2 through which the debinding process for the ceramic product is made. The heater 113 is provided to provide a heat source to increase the temperature suitable for the.

Here, the heater 113 may be provided as an electric coil wound around the outer surfaces of the left and right pulse pipes 111 and 112 passing through the inner wall of the furnace body 2 to provide a heat source when power is applied.

In this case, the pulsed gas supplied into the left and right pulse pipes 111 and 112 is heated up to a temperature higher than room temperature by the heater 113 to meet the working conditions by the heater 113 before supplying the internal passage ( 3) It is supplied to the inside can be stably performed in the binder removal process without lowering the thermal efficiency of the firing furnace (100).

On the other hand, the pulse gas supply line 120 for supplying the atmosphere gas which is the pulse gas to the pulse supply mechanism 110 consisting of the left and right pulse pipes (111, 112) is injected to the side of the receiving portion (7) Control valves 121 and 122 are provided in the middle of the length so as to control the supply of the pulsed gas, and are connected to the pulse supply mechanism 110.

In addition, the pulse gas supply line 120 is provided in the pulse gas supply line 120 in the same manner as the flow meter 9a provided in the main gas supply line 9 so as to measure the supply amount of the atmospheric gas supplied to the side air supply mechanism 5. Flowmeters 120a are respectively provided to measure the supply amount of the pulse atmosphere gas supplied to the side.

Here, the atmospheric gas supplied to the inner passage 3 through the side air supply mechanism 5 and the pulse air supply mechanism 110 is a reducing nitrogen gas.

In addition, the control valves 121 and 122 are turned on / off so that the pulse gas from the left and right pulse pipes 111 and 112 provided on the left and right sides of the furnace body 2 is not simultaneously supplied into the inner passage 3. Each of the timers 121a and 122a for controlling the off at a constant cycle is provided.

Accordingly, the control valves 121 and 122 for controlling the gas flow of the left and right pulse pipes 111 and 112 are provided while supplying the pulse gas through the left pulse pipe 111 for a predetermined time. To stop the supply of the pulsed gas through the right pulse pipe 112 and, on the contrary, to stop the supply of the pulsed gas through the left pulse pipe 111 while supplying the pulsed gas through the right pulse pipe 112. By controlling the on / off alternately by the timer (121a, 122a) it is possible to prevent the pulse gas of the left and right pulse pipes (111, 112) are simultaneously supplied into the inner passage to cancel each other.

Here, the gas injected from the front end of the left, right pulse pipe (111, 112) by the control valve 121, 122 so as to have an injection speed that penetrates the receiving portion 7 in the horizontal direction. The opening size is adjusted.

In addition, the pulse gas supply line 120 is composed of a branch line branched from the main gas supply line (9) for supplying the atmosphere gas to the side air supply (5) or to supply the pulse gas into the inner passage separately It can be configured as an independent line.

Then, the exhaust line of the upper exhaust pipe (6) while the rapid supply of pulse gas from the left and right sides of the furnace main body 2 to the center side of the inner passage (3) is made through the left and right pulse pipes (111, 112) When the exhaust fan (6c) connected to 10) is operated, the atmosphere gas containing harmful gas generated during the debinder process through the upper exhaust port 6 is discharged to the outdoors.

According to the present invention as described above, by adding a pulse supply mechanism for supplying the pulsed gas into the inner passage near the side supply mechanism for constantly supplying the atmosphere gas into the furnace body, the upper exhaust air in the internal passage in the binder removal area Since the air supply flow rate can be increased or decreased instantaneously to the side of the receiving part of the chamber, a strong, rapid gas vortex is formed in the debinder area to suppress the formation of dead zones in which the gas is stagnant, and to uniform the atmospheric gas in the furnace. In addition, it is possible to produce an excellent quality ceramic product without cracking and peeling by smoothly maintaining the upper exhaust of harmful gases which adversely affect the firing process.

While the invention has been shown and described with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit or scope of the invention as set forth in the claims below. I would like to clarify that knowledge is easy to know.

Claims (8)

A furnace body having an inner passage, a heating element for providing a heat source to the inner passage, a side air supply for supplying atmospheric gas from the side of the furnace body to the center portion, an upper exhaust pipe for discharging the gas of the furnace body to the top; In the firing furnace for firing the ceramic product having a conveying section for transporting in one direction the receiving portion in which the unbaked ceramic product is loaded, In the vicinity of the side air supply structure to form a pulse gas flow in parallel with the main gas flow for supplying the atmosphere gas to the central portion of the inner passage through the side air supply to the side of the receiving portion from the left and right sides of the furnace body. A pulse supply mechanism installed; An intermittent air supply system, comprising: a pulse gas supply line for supplying an atmosphere gas to the pulse supply mechanism, and having a control valve installed in the middle of the length of the control valve for controlling supply of pulse gas injected to the side of the accommodating part; Continuous firing furnace having. The method of claim 1, The pulsed supply mechanism is a continuous firing furnace having an intermittent air supply system, characterized in that installed at a predetermined interval in the binder removal area. The method of claim 1, The pulse supply mechanism is an intermittent type comprising a plurality of left and right pulse pipes arranged horizontally on both the left and right sides of the furnace main body so that the front and rear ends of the accommodating part are exposed to the inner passage. Continuous firing furnace with air supply system. The method of claim 3, wherein A continuous firing furnace having an intermittent air supply system, characterized in that the plurality of left and right pulse pipes arranged perpendicular to the left and right sides of the furnace body are arranged at different heights. The method of claim 1, The regulating valve is a continuous firing furnace having an intermittent air supply system, characterized in that it comprises a timer for controlling the on / off at regular intervals so that the pulsed gas from the left and right pulse pipes are not simultaneously supplied into the inner passage. The method of claim 3, wherein The left and right pulse pipe is a continuous firing furnace having an intermittent air supply system, characterized in that the heater is mounted to raise the temperature of the pulsed gas supplied into the inner passage. The method of claim 1, The pulsed gas supply line is a continuous firing furnace having an intermittent air supply system, characterized in that the branch line branched from the main gas supply line for supplying the atmosphere gas to the side air supply. The method of claim 1, The pulse gas supply line is a continuous firing furnace having an intermittent air supply system, characterized in that the independent line for supplying a separate pulse gas into the inner passage.

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