JP4325004B2 - Drip-proof device in the firing furnace - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a green ceramic relates baked Naruro baking by heating by a heater.
[0002]
[Prior art]
Conventionally, a firing furnace for firing, for example, a low-temperature fired ceramic substrate is conveyed into the firing furnace by a conveyor 2 with the unfired ceramic substrate 1 placed on a firing support 7 as shown in FIG. The unfired ceramic substrate 1 is heated and fired by the heater 5 of the firing furnace while the furnace entrance 3 is shut off from the outside air by the air curtain 4. At this time, in order to promote decomposition / removal (debinding) of the binder contained in the unfired ceramic substrate 1, outside air is sent into the firing furnace from the air pipe 6 and the binder decomposition gas is exhausted from the exhaust pipe (not shown). Etc.) to the outside.
[0003]
[Problems to be solved by the invention]
By the way, in the baking furnace of the said structure, since the internal pressure of a baking furnace is a little higher than external pressure by the blowing of the air from the air piping 6 in a baking furnace, the air in a baking furnace is little from the air curtain 4 of the inlet 3 little by little. As a result of leakage to the outside, part of the binder decomposition gas flows back from the heater 5 side to the inlet 3 side. In the region on the inlet 3 side (upstream side of the heater 5) from the heater 5 in the firing furnace, the temperature of the air pipe 6 and the furnace inner wall in the firing furnace is lower than the ambient temperature around the heater 5. The binder decomposition gas that has flowed back to the upstream side is cooled and liquefied (condensed) by touching the air piping 6 in the firing furnace, the inner wall of the furnace, and the like, and adheres to these surfaces. For this reason, the decomposed gas liquefied component may drop from the air piping 6 in the firing furnace or the ceiling of the furnace inner wall and drop onto the surface of the unfired ceramic substrate 1 being transported. Defects such as cracks and dirt may occur.
[0004]
The present invention has been made in view of such circumstances. Therefore, the object of the present invention is to prevent the liquefied portion of the binder decomposition gas from falling on the unfired ceramic surface in the firing furnace, and to improve the yield of fired products. The object is to provide a firing furnace that can be improved.
[0005]
[Means for Solving the Problems]
In consideration of the fact that the liquefaction phenomenon of the binder decomposition gas occurs in a region where the atmospheric temperature is relatively low from the vicinity of the entrance of the firing furnace to the vicinity of the heater, in claim 1 of the present invention, from the vicinity of the entrance of the firing furnace to the vicinity of the heater. in the region of up to, those so as to present a space between the green ceramic and fired support Rutotomoni provided drip plate covering the upper side of the conveyor for conveying a drip-proof plate and the furnace inner wall ceiling calciner It is. In this way, even if the cracked gas liquefaction drops as drops from the air piping, the furnace inner wall ceiling, etc. in the region where the ambient temperature from the furnace inlet to the heater is relatively low, the cracked gas liquefaction Is received on the top surface of the drip-proof plate and is prevented from falling on the surface of the unfired ceramic being conveyed.
[0006]
In this case, as in the second aspect, the drip-proof plate is preferably formed so that the central portion is high and becomes low toward both sides of the conveyor. In this way, even if the binder decomposition gas is liquefied on the lower surface of the drip-proof plate, the decomposed gas liquefaction component flows laterally along the inclination of the lower surface of the drip-proof plate. As a result, when the decomposed gas liquefied component falls from the bottom surface of the drip-proof plate, it does not fall from the vicinity of the center of the bottom surface of the drip-proof plate, but falls from the side edge of the drip-proof plate, Falling of the decomposed gas liquefaction from the lower surface of the plate to the unfired ceramic surface is prevented.
[0007]
Further, as in claim 3, it is preferable that the drip-proof plate is detachably mounted on the mounting portion provided on the inner wall of the firing furnace from the inlet side. In this way, the drip-proof plate can be easily detached and the drip-proof plate can be easily cleaned.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is applied to a low-temperature fired ceramic substrate firing furnace will be described with reference to FIGS. 1 and 2. An unfired ceramic substrate 11 formed of a low-temperature fired ceramic green sheet is placed on a heat-resistant fired support 19 and conveyed by the conveyor 12 through the core 20 of the firing furnace. The green sheet forming the green ceramic substrate 11 is made by tape-molding a slurry in which a low-temperature fired ceramic powder is mixed with a binder (resin), a solvent, and the like.
[0009]
The inlet 13 of the furnace core 20 is blocked from the outside air by an air curtain 14. A plurality of heaters 15 for adjusting the temperature distribution in the conveying direction in the furnace core 20 to a predetermined temperature distribution (peak temperature 800 to 1000 ° C.) are installed on the outer periphery of the furnace core 20. A plurality of air pipes 16 for feeding outside air into the furnace core 20 are drawn into the furnace core 20 from between the air curtain 14 and the heater 15, and are piped in the conveying direction along the ceiling surface of the furnace core 20. Has been.
[0010]
Furthermore, between the vicinity of the air curtain 14 at the inlet 13 and the vicinity of the first heater 15, a drip-proof plate 17 formed of, for example, stainless steel, a core material or the like is installed so as to cover the top of the conveyor 12. As shown in FIG. 2, the drip-proof plate 17 is formed in a curved surface shape such that the center portion is high and becomes lower toward both sides of the conveyor 12. The drip-proof plate 17 is fitted and attached to a hook-shaped mounting portion 18 fixed to the inner wall of the furnace core 20 so as to be detachable from the inlet 13 side in the transport direction.
[0011]
In the firing furnace configured as described above, outside air is sent from the air pipe 16 into the furnace core 20 in a state where the inlet 13 is shut off from the outside air by the air curtain 14, and is arranged along the conveying direction on the outer periphery of the furnace core 20. The temperature distribution in the conveying direction in the furnace core 20 is adjusted to a predetermined temperature distribution (peak temperature 800 to 1000 ° C.) by the plurality of heaters 15. In this state, the unfired ceramic substrate 11 transported in the furnace core 20 by the conveyor 12 is sintered at 800 to 1000 ° C. after the binder is decomposed and removed (debindered) in the transport process.
[0012]
At this time, cracked gas generated by debinding in the furnace core 20 is discharged to the outside through an exhaust pipe (not shown), but a part of the cracked gas passes through the furnace core 20 on the inlet 13 side (of the heater 15). Back flow upstream). Even in the furnace core 20, since the atmosphere temperature is relatively low in the region from the inlet 13 to the first heater 15, the cracked gas that has flowed back to the upstream side of the heater 15 flows into the air piping 16 and the furnace inner wall in the furnace core 20. It is cooled by touch and liquefies, and adheres to those surfaces. For this reason, the decomposed gas liquefied component may fall as a drop from the air pipe 16 in the furnace core 20 or the ceiling of the furnace core 20, but in this embodiment, from the air curtain 14 to the vicinity of the first heater 15. In this region, the drip-proof plate 17 is installed so as to cover the upper part of the conveyor 12, so that the decomposed gas liquefied component falling from the air pipe 16 or the ceiling in the furnace core 20 is on the upper surface of the drip-proof plate 17. It is received and flows to the side along the inclination of the drip-proof plate 17 and flows downward along the inner wall of the furnace core 20.
[0013]
Further, even when the decomposition gas of the binder is liquefied on the lower surface of the drip-proof plate 17, the decomposed gas liquefaction part flows sideways along the inclination of the lower surface of the drip-proof plate 17 and travels along the inner wall of the furnace core 20. Flows downward. Thereby, it is possible to prevent the decomposed gas liquefied component from falling on the surface of the unfired ceramic substrate 11 being conveyed, and to improve the yield of the fired product. In addition, since the installation position of the drip-proof plate 17 is only in the region where the ambient temperature from the inlet 13 to the first heater 15 is low, the flow of air and the temperature distribution in the furnace core 20 are almost affected. There is no loss of binder removal and sinterability.
[0014]
In this embodiment, the drip-proof plate 17 is detachably attached to the attachment portion 18 on the inner wall of the furnace core 20 from the inlet 13 side. Can be easily detached from the inlet 13 of the furnace core 20, and workability during cleaning of the drip-proof plate 17 can be improved. However, the drip-proof plate 17 may be attached by other methods. For example, the drip-proof plate 17 may be suspended from the ceiling surface of the furnace core 20 or may be fixed to the inner wall of the furnace core 20 with a metal fitting or the like. Alternatively, a soot may be provided below both side edges of the drip-proof plate 17 so that the decomposed gas liquefied portion flowing down from both side edges of the drip-proof board 17 is received by the scissors and discharged to the outside.
[0015]
In the present embodiment, the drip-proof plate 17 is curved in a convex shape, but the drip-proof plate 17 may be bent into an inverted V shape. In short, the central portion of the drip-proof plate 17 is high, and the conveyor If it forms so that it may become low toward the both sides of 12, the decomposition gas liquefied part of the upper and lower surfaces of the drip-proof board 17 can be poured to the side. However, the shape of the drip-proof plate 17 may be appropriately changed as long as it does not drop the decomposition gas liquefied component onto the surface of the unfired ceramic substrate 11.
[0016]
Further, in the present embodiment, the mounting portion 18 that supports the drip-proof plate 17 is divided and arranged in a plurality of locations, but this may be formed in a single rail shape that extends over the entire length of the drip-proof plate 17, Further, the mounting portion is formed in a bowl shape extending over the entire length of the drip-proof plate 17, and is configured to receive the decomposed gas liquefied portion flowing down from the drip-proof plate 17 and discharge it to the outside. Also good.
In addition, the present invention is not limited to a low-temperature fired ceramic firing furnace, and can be applied to other ceramic firing furnaces such as alumina.
[0017]
【The invention's effect】
As apparent from the above description, according to claim 1 of the present invention, in the region from near the entrance of the firing furnace to the vicinity of the heater, Rutotomoni provided drip plate covering the upper side of the conveyor, the drip-proof plate baking Since there is a space between the furnace inner wall ceiling of the furnace, the decomposed gas liquefaction falling from the air piping in the firing furnace, the ceiling of the furnace inner wall, etc. can be received on the upper surface of the drip-proof plate. The decomposition gas liquefaction drop on the surface of the fired ceramic can be prevented, and the yield of the fired product can be improved.
[0018]
Further, in claim 2, since the drip-proof plate is formed so as to have a high central portion and lower toward both sides of the conveyor, the decomposed gas liquefaction adhering to the lower surface of the drip-proof plate is reduced on the lower surface of the drip-proof plate. It flows to the side along the inclination, and the fall of the decomposed gas liquefied part from the lower surface of the drip-proof plate to the unfired ceramic surface can be prevented.
[0019]
Further, according to the third aspect, since the drip-proof plate can be detachably attached from the inlet side, the workability of cleaning the drip-proof plate can be improved.
[Brief description of the drawings]
1 is a longitudinal side view of a firing furnace according to an embodiment of the present invention. FIG. 2 is a longitudinal front view of the firing furnace. FIG. 3 is a longitudinal side view of a conventional firing furnace.
DESCRIPTION OF SYMBOLS 11 ... Unbaked ceramic substrate, 13 ... Inlet, 14 ... Air curtain, 15 ... Heater, 16 ... Air piping, 17 ... Drip-proof board, 18 ... Mounting part, 19 ... Firing support, 20 ... Furnace core.

Claims (3)

In a firing furnace that heats and fires an unfired ceramic that is carried into the furnace by a heater in the furnace,
In a region from the vicinity of the entrance of the firing furnace to the vicinity of the heater, a drip-proof plate is disposed that covers the top of the conveyor that conveys the unfired ceramic ,
A firing furnace characterized in that a space exists between the drip-proof plate and the ceiling of the furnace inner wall of the firing furnace . The firing furnace according to claim 1, wherein the drip-proof plate is formed so as to have a high central portion and become lower toward both sides of the conveyor. The Boshizukuban is the mounting portion provided on the inner wall of the firing furnace, the firing furnace according to claim 1 or 2, characterized in that it is detachably mounted from the inlet side.

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