JPH06123559A - Firing furnace of inside-outside simultaneous firing type for dome shaped ceramic product - Google Patents

Abstract

PURPOSE:To make it possible to fire a dome shaped ceramic product for use in medical service even if it has a large dimension without generating inside and outside mottles by providing a longitudinal heater and a lateral heater for firing from the outside and an internal heater for firing which protrudes inwardly from the bottom of a firing room. CONSTITUTION:A blow cylinder 28 having a large number of blow holes 29 formed from fireproof material of silicon carbide is provided at the center of the upper surface of a mounting base 27 and inside the cylinder 28 there is an exhaust tube 31 around which an internal heater 33 of nickel-chromium wire is wound. If a power cord is connected to a socket 34, the heater 33 is heated to a red heat and emits radiant heat, which is carried by the air fed from an end 30, and is blown off from the holes 29 of the cylinder 28 to fire a dome shaped ceramic product 4 from the inside thereof. The external surface is fired by a longitudinal heater 16 and a lateral heater 17. As a result, even a large dome shaped ceramic product for medical service can be fired without generating inside and outside mottles and harmful gas in the inside can be removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal and external simultaneous firing type dome-shaped ceramic product firing furnace.

[0002]

2. Description of the Related Art In the publicly known Japanese Utility Model Laid-Open No. 1-116394, a firing chamber in which a mere ceramic product, not a dome, can be housed and fired, and a plurality of upper and lower front and rear directions provided near the inner wall surface of the firing chamber It consists of a heater, a carriage that travels on rails provided on the floor, a lift mechanism that is mounted on the carriage, and a furnace bottom that moves up and down by the lift mechanism. A firing furnace for ceramic products, in which a placing table formed of a horizontal perforated plate is provided, small ceramic products are placed side by side on the placing table, and gas supplied from a gas supply pipe is circulated through the placing table of the perforated plate. Is described.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The one described in Japanese Patent No. 116394 has three heaters in the front-back direction, which are provided in the vicinity of the inner wall of the firing chamber, but does not have heaters in the left-right direction, so firing of a cylindrical ceramic product such as a dome. However, since the left and right sides are not fired, there is a problem of uneven firing. For example, a magnetic shield container made of bismuth-based superconducting material that makes full use of atmospheric plasma and thermal spraying technology is a dome-shaped container that is large enough to wrap humans, and is coated with superconducting material to create a weak magnetic field in the human brain. It is used for the diagnosis and treatment of brain disorders such as brain tumors and epilepsy, in addition to measuring brain function and elucidating brain function. Since such a dome-shaped ceramic product is very large, the firing furnace for firing the dome-shaped ceramic product is many times larger than a generally known one. Therefore, unlike the known example, a horizontal heater is not provided. As a result, the temperature varies and the firing becomes uneven. Further, if the dome-shaped ceramic product is fired only from the outer surface side, there is a problem in that the firing of the inside is delayed or various harmful gases are accumulated in the inside so that it becomes uninteresting.

[0004]

Therefore, according to the present invention, the firing chamber 15 in which the dome-shaped ceramic product 4 can be stored and fired.
A front and rear direction heater 16 and a left and right direction heater 17 for firing the upper and lower dome-shaped ceramic products 4 provided in the vicinity of the inner wall surface of the firing chamber 15 from the outside, and the dome from the furnace bottom of the firing chamber 15. This is a firing furnace for a dome-shaped ceramic product which is an internal / external co-firing type, which comprises an internal heater 33 which projects into the interior of the type ceramic product 4 and fires the dome-shaped ceramic product 4 from the inside. Further, the present invention, in the firing furnace, the furnace bottom of the firing furnace,
An elevating trolley / furnace bottom 5 is provided, and a mounting table 27 is provided on the trolley / furnace bottom 5 via a supporting table 26 protruding upward, and a silicon carbide refractory material is provided at the center of the upper surface of the mounting table 27. Ejection cylinder 28 for ejecting hot air, which has a large number of ejection openings 29 on the circumferential surface formed by
Is provided with an internal heater 33 made of nickel-chromium wire or the like in the ejection tube 28 for degassing.
1 is a firing furnace for dome-shaped ceramic products that are simultaneously fired inside and outside.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the firing furnace of the present invention will be described. Reference numeral 1 is an electric furnace, which is placed on an upper part of an underframe 3 provided on a floor 2 as shown in FIG. The underframe 3 is used
This is because the dome-shaped ceramic product 4 that is large enough for a human to fit in is carried laterally by the carriage and hearth 5 and supplied into the electric furnace 1 from below. It has a shape having desk-like legs 6 so that a dolly / furnace bottom 5 can enter from the side, and has a lift mechanism 7 inside.

Reference numeral 8 denotes a cylinder of the lift mechanism 7, and when the cylinder 8 expands and contracts, the lift mechanism 7 moves up and down between the position where the temporary line is lowered and the position where the solid line is raised, and also serves as a trolley that travels on the floor 2 to transfer. The furnace bottom 5 is raised and lowered. At the center of the platform surface 9 of the underframe 3, a vertically extending entrance 10 is provided, and the lower end 11 of the electric furnace 1 is attached in close contact with the upper surface of the entrance 10. The doorway 10 is continuous to the lower end 11.

The outer wall of the electric furnace 1 of the embodiment is surrounded by an outer iron plate 12, a ceramic fiber layer 13 is formed inside the outer iron plate 12, and a ceramic board layer 14 is formed inside the ceramic fiber layer 13. The inside of the ceramic board layer 14 is a firing chamber 15, and in the firing chamber 15, the front-back heater 16 and the left-right heater 1 are placed in a state of history.
7 are provided (FIG. 3). The front-rear direction heater 16 and the left-right direction heater 17 are horizontally provided in the vicinity of the ceramic board layer 14, and are arranged in a plurality at a predetermined interval in the vertical direction (12 in the drawing). .

Inside the front-rear heater 16 and the left-right heater 17, in order to prevent heat from the front-rear heater 16 and the left-right heater 17 from being directly applied to the dome-shaped ceramic product 4, a silicon carbide material is used. The front and rear belt-shaped plates 18 and the left and right belt-shaped plates 19 are provided to form the front and rear belt-shaped plates 18.
The dome-shaped ceramic product 4 is fired by radiant heat through the left and right strip-shaped plates 19.

In the present invention, the horizontal heat-resistant partition steel 20 is provided in order to divide the firing chamber 15 into a plurality of sections in the vertical direction. The horizontal heat-resistant partition steel 20 has its outer end fixed to the inner surface of the outer iron plate 12, and its inner end 21 has the front and rear strips 1 described above.
The horizontal heat-resistant partition steel 20 forms an upper zone 22, a middle zone 23, and a lower zone 24 by projecting between 8 and the left and right strips 19 into the firing chamber 15.

The front and rear heaters 16 and the left and right heaters 17 in the upper zone 22, the middle zone 23 and the lower zone 24 are respectively connected to an automatic control mechanism 25 to eliminate the upper concentration of hot air and to reduce the temperature difference between the upper and lower sides. ± 15 at maximum
To ℃.

The trolley / furnace bottom 5 is an inverter-controlled motor drive system with a speed reducer, is remote-controlled, has a soft start / soft stop mechanism, and has a variable speed. The lift mechanism 7 includes two cylinders 8.
This is used and comes with a safety stopper. The automatic control mechanism 25 uses a digital program setting device, a temperature controller of a digital support controller, and an SCR power controller so that smooth temperature control can be performed, and a digital temperature controller for monitoring the heater temperature. Is set to suppress partial high temperature.

Although the carriage / furnace bottom 5 may have a structure in which the vertical width is not so thick as shown in FIG. 1, it is effective to have an extremely thick structure as shown in FIG. That is, the mounting table 27 is provided via the support table 26, and the mounting table 27
Place the dome-shaped ceramic product 4 on top. Then, inside the dome-shaped ceramic product 4 of the mounting table 27, an ejection cylinder 28 made of a silicon carbide refractory is provided. Reference numeral 29 denotes a large number of ejection ports formed in the ejection cylinder 28. In the case of FIG. 3, the trolley-cum-furnace bottom 5 has a large thickness so as to project below the bed surface 9 of the underframe 3, and the lower end of the ejection cylinder 28 is
It penetrates through the mounting table 27 and pierces the dolly / furnace bottom 5, and its end portion 30 projects laterally from the dolly / furnace bottom 5.

An exhaust tube 31 integral with the ejection cylinder 28 is provided in the ejection cylinder 28. The upper end of the exhaust tube 31 is fixed to the ceiling surface of the ejection cylinder 28, and the lower end thereof penetrates the mounting table 27 and pierces the trolley / furnace bottom 5 and its end 32 is formed.
Is laterally protruding from the dolly / furnace bottom 5. Reference numeral 33 is an internal heater made of nickel chrome wire or the like, and 34 is an insertion socket thereof.

[0014]

[Operation] Next, the operation will be described. A mounting table 27 is mounted on the carriage / furnace bottom 5 via a supporting table 26.
At the center of the upper surface of the nozzle, there is provided an ejection tube 28 having a large number of ejection openings 29 formed of silicon carbide refractory, and in the ejection tube 28, an exhaust tube 31 around which an internal heater 33 made of nickel chrome wire or the like is wound. Is provided, the upper end of the exhaust tube 31 is fixed to the ceiling surface of the ejection pipe 28, and the lower end penetrates the mounting table 27 and pierces the dolly / furnace bottom 5, and the end 32 thereof is lateral to the dolly / furnace bottom 5. Since the lower end of the ejection pipe 28 also penetrates the mounting table 27 and sticks into the carriage / furnace bottom 5, the end 30 thereof projects laterally from the carriage / furnace bottom 5.
When the dome-shaped ceramic product 4 is put on the trolley-cum-furnace bottom 5, the internal heater 33 is placed in the dome-shaped ceramic product 4.
Will come to you.

Therefore, the carriage / furnace bottom 5 is soft-started and placed on the lift mechanism 7 descending like a temporary line,
Soft stop. Then, when operating the cylinder 8,
The lift mechanism 7 rises as shown by the solid line, and the dome-shaped ceramic product 4 is housed in the firing chamber 15 of the electric furnace 1 from the entrance / exit 10 of the base surface 9 of the underframe 3, and at the lower end of the firing chamber 15, the trolley-cum-bottom is provided. 5 is closely attached.

In FIG. 3, in this state, the end portions 30, 3 are
Since No. 2 is exposed to the outside, when a blower is connected to the end 30 and a power cord is connected to the socket 34, the internal heater 33 glows red and emits radiant heat, and the air supplied from the end 30 moves the heater. Spout 29 of spouted spout 28
The dome-shaped ceramic product 4 is further ejected and fired from the inside. The outer surface of the dome-shaped ceramic product 4 is fired by the front-back heater 16 and the left-right heater 17.

[0017]

According to the known Japanese Utility Model Laid-Open No. 1-116394, upper and lower three front-back heaters are provided near the inner wall of the firing chamber, but no left-right heaters are provided. When firing a cylindrical ceramic product such as a dome, the left and right sides are not fired, which causes uneven firing. For example, a magnetic shield container made of bismuth-based superconducting material that makes full use of atmospheric plasma and thermal spraying technology is a dome-shaped container that is large enough to wrap humans, and is coated with superconducting material to create a weak magnetic field in the human brain. It is used for the diagnosis and treatment of brain disorders such as brain tumors and epilepsy, in addition to measuring brain function and elucidating brain function. Since such a dome-shaped ceramic product is very large, the firing furnace for firing the dome-shaped ceramic product is many times larger than a generally known one. Therefore, unlike the known example, a horizontal heater is not provided. As a result, the temperature varies and the firing becomes uneven. In addition, the dome-shaped ceramic products are
If firing is performed only from the outer surface side, there is a problem that firing of the inside is delayed or various harmful gases are accumulated inside, resulting in an uninteresting state.

However, according to the present invention, the firing chamber 15 in which the dome-shaped ceramic product 4 can be housed and fired, and the firing chamber 1
The front-back heater 1 for firing a plurality of upper and lower dome-shaped ceramic products 4 provided near the inner wall surface of the heater 5 from the outside
6 and the left-right direction heater 17 and an inner-outer simultaneous firing type dome type including an inner heater 33 that projects from the furnace bottom of the firing chamber 15 into the dome-shaped ceramic product 4 and fires the dome-shaped ceramic product 4 from the inside. Since it is a firing furnace for ceramic products, it has an effect of firing even a very large dome-shaped ceramic product for medical purposes without unevenness. Further, the present invention, in the above firing furnace,
The furnace bottom of the firing furnace is an elevator trolley / furnace bottom 5, and a pedestal 27 is provided on the trolley / furnace bottom 5 via a support pedestal 26 protruding upward. Is provided with an ejection cylinder 28 for ejecting hot air, which has a large number of ejection openings 29 on the peripheral surface formed of a silicon carbide refractory, and an internal heater 33 made of nickel-chrome wire or the like is wound inside the ejection cylinder 28. Since this is a firing furnace for dome-shaped ceramic products that are simultaneously fired inside and outside, provided with an exhaust tube 31 for degassing, even a very large dome-shaped ceramic product for medical use can be fired without unevenness inside and outside, It also has the effect that the harmful gas can be eliminated and good firing can be performed.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of the present invention.

FIG. 2 is a cross-sectional plan view of the present invention.

FIG. 3 is a diagram of another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electric furnace, 2 ... Floor, 3 ... Underframe, 4 ... Dome-shaped ceramic product, 5 ... Carriage and furnace bottom, 6 ... Legs, 7 ... Lift mechanism, 8
... Cylinder, 9 ... Platform surface, 10 ... Doorway, 11 ... Bottom end, 1
2 ... Outer iron plate, 13 ... Ceramic fiber layer, 14 ...
Ceramic board layer, 15 ... Firing chamber, 16 ... Front-back heater, 17 ... Left-right heater, 18 ... Front-back strip plate, 19
… Left and right band plates, 20… Horizontal heat-resistant partition steel, 21… Inner end, 2
2 ... upper zone, 23 ... middle zone, 24 ... lower zone, 25 ... automatic control mechanism, 26 ... support stand, 27 ... mounting stand, 28 ... ejection cylinder, 29 ... ejection port, 30 ... end, 31 ...
Exhaust tube, 32 ... End portion, 33 ... Internal heater, 34 ...
socket.

Claims (2)

[Claims] 1. A firing chamber 15 in which a dome-shaped ceramic product 4 can be housed and fired, and a plurality of upper and lower dome-shaped ceramic products 4 provided near the inner wall surface of the firing chamber 15 before and after firing from the outside. Simultaneous internal and external firing system comprising a directional heater 16 and a horizontal heater 17, and an internal heater 33 which projects from the furnace bottom of the firing chamber 15 into the dome-shaped ceramic product 4 and fires the dome-shaped ceramic product 4 from the inside. Firing furnace for dome-shaped ceramic products. 2. The furnace bottom of the firing furnace according to claim 1, which is a lift-carrying-carriage / furnace bottom 5, and a mounting table 27 is mounted on the car-carrying / furnace bottom 5 via a supporting table 26 protruding upward. Is provided
At the center of the upper surface of the mounting table 27, a jetting pipe 28 for jetting hot air having a large number of jetting ports 29 on the peripheral surface formed of silicon carbide refractory is provided. Inner and outer simultaneous firing type dome-shaped ceramic product firing furnace provided with an exhaust tube 31 for degassing around which an internal heater 33 is wound.