JP4178304B2 - Heater holding structure and heat treatment furnace using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat treatment furnace, and more particularly to a heater holding structure for a high-temperature heater used in a ceramic firing furnace or the like.
[0002]
[Prior art]
Conventionally, a rod-shaped ceramic heater has been used as a heat source in a ceramic batch firing furnace. When this rod-shaped ceramic heater is installed vertically, the ceramic heater is suspended from a heater insertion port provided on the furnace ceiling of the firing furnace.
[0003]
As shown in FIG. 7, the conventional heater holding structure 20 is provided with a heater holding pipe 23 having an inner diameter larger than the outer diameter of the ceramic heater 21 at the heater insertion port 24 a of the furnace ceiling 24. On the other hand, a through hole 21a is formed near the end of the ceramic heater 21, and a metal split pin 22 is passed through the through hole 21a. Regarding the suspension of the ceramic heater 21, the ceramic heater 21 is inserted into the furnace from the heater insertion port 24a via the heater holding tube 23, and at that time, the split pin 22 inserted into the through hole 21a of the ceramic heater 21 is held by the heater. The ceramic heater 21 is suspended from the upper surface of the pipe 23. Moreover, the front-end | tip part of the split pin 22 which protrudes so that the split pin 22 inserted in the through-hole 21a of the ceramic heater 21 may not come off is bent and fixed.
[0004]
[Problems to be solved by the invention]
However, the conventional heater holding structure has the following problems.
1. Since the split pin inserted into the heater is made of metal, a spiral heater in which both the positive pole and the negative pole are located at the end of the heater holding side is short-circuited via the split pin.
[0005]
2. The tip of the bent cotter pin may come into contact with the surrounding area, possibly leading to electric leakage.
[0006]
3. Since the end of the heater becomes high in temperature, the material deterioration is particularly short with a metal split pin.
[0007]
4). Since the tip portion of the split pin is bent, the bent portion is liable to cause brittle fracture.
[0008]
SUMMARY OF THE INVENTION An object of the present invention is to provide a heater holding structure that has no risk of electric leakage or short-circuiting and that has little material deterioration even when exposed to high temperatures and has a long life.
[0009]
[Means for Solving the Problems]
The present invention has been made in view of the above object. A heater holding structure according to a first aspect of the present invention is a heater holding structure that holds a heater in a substantially vertical downward direction from a furnace ceiling of a heat treatment furnace, the rod-shaped heater having a through-hole formed in the vicinity of one end thereof, A heater holding pin inserted into a through hole of the heater and having a length larger than the outer diameter of the heater and a heater insertion port provided in the furnace ceiling are installed, and the heater is inserted into the heater. A heater holding tube for holding the holding pin and a pin drop-off prevention tool. The heater is inserted into the heater holding tube, and the heater holding pin inserted into the through hole of the heater is connected to the upper surface of the heater holding tube . The heater is suspended from the furnace ceiling, and a pin drop prevention tool is put on the outside of the heater holding pin and the heater holding tube.
[0010]
By adopting such a configuration, ceramics having excellent heat resistance and insulation can be used for the heater holding pins. In other words, the heater holding pin is latched on the upper surface of the heater holding tube, and a pin drop prevention device is put on the outside of the heater holding tube, so that the heater holding pin can be removed from the heater without providing a latching portion on the heater protection tube. Can be prevented. Therefore, materials other than metal that cannot be bent can be used. Furthermore, since it is not necessary to deform the heater holding pin, it can be used repeatedly.
[0011]
Furthermore, the heat treatment furnace of the second invention has a heat treatment space composed of a furnace ceiling, a furnace wall, and a hearth, and uses the heater holding structure according to any one of claims 1 to 3. The heater is inserted and held in the heat treatment space.
[0012]
By adopting such a configuration, it is possible to provide a heat treatment furnace that has a long heater holding structure and has no risk of short circuit or electric leakage.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
FIG. 1 is a schematic sectional view showing a heater holding structure which is a reference of the present invention, FIG. 2 is an exploded perspective view showing a heater holding structure which is a reference of the present invention, and FIG. 3 is a hook of a heater holding pipe which is a reference of the present invention. FIG. 4 is a schematic sectional view showing the heater holding structure of the present invention, and FIG. 5 is an exploded perspective view showing the heater holding structure of the present invention.
[0014]
As shown in FIG. 4 or FIG. 5, the heater holding structure 1 of the present invention includes a heater 3, a heater holding pin 5, a heater holding tube 7, and a pin dropout prevention tool 11.
[0015]
The heater 3 is composed of a rod heater, a spiral heater or the like, and is held substantially vertically. Further, a through hole 3a for inserting the heater holding pin 5 is formed in the vicinity of the upper end portion of the heater 3 so as to be orthogonal to the longitudinal direction. In addition, examples of the material of the heater 3 include silicon carbide and zirconia, but are not particularly limited.
[0016]
The heater holding pin 5 is inserted into the through hole 3 a of the heater 3 to suspend the heater 3. The heater holding pin 5 may be inserted into the through hole 3a of the heater 3 and may have a length larger than the outer diameter of the heater 3. Moreover, the shape of the heater holding pin 5 may be a columnar shape or a prismatic shape, but it is preferable to match the cross-sectional shape with the through hole 3a of the heater 3 in order to securely fix the heater. . Moreover, it is preferable to use the material of the heater holding pin 5 that is excellent in heat resistance, mechanical strength, and insulation. Specific examples include alumina, aluminum nitride, and silicon nitride.
[0017]
The heater holding tube 7 is provided so as to cover the heater insertion port 13a provided in the furnace ceiling 13 of the heat treatment furnace, and the heater holding pin 5 is hooked on the upper surface thereof to suspend the heater 3. belongs to. The heater holding tube 7 has an inner diameter that allows the heater 3 to be inserted inside, and a fixing portion 7a for fixing the heater holding tube 7 to the furnace ceiling 13 by projecting a part of the outer surface to the outside. It is said. The material of the heater holding tube 7 is preferably excellent in heat resistance and mechanical strength. Specifically, as with the heater holding pin 5, alumina, aluminum nitride, and silicon nitride can be used.
[0018]
Here, as shown in FIG. 4 or 5, the heater holding pin 5 is directly hooked on the upper surface of the heater holding tube 7, and then the pin is dropped from the outside of the heater holding tube 7 so that the heater holding pin 5 does not fall off. The heater holding pin 5 can be more firmly fixed by mounting the preventer 11 and holding the heater holding pin 5 from the longitudinal direction. The pin drop-off prevention tool 11 has a cylindrical shape, and its inner diameter matches the outer diameter of the heater holding tube 7.
[0019]
Next, the heat treatment furnace will be described. FIG. 6 is a schematic sectional view showing a heat treatment furnace of the present invention. As shown in FIG. 6, the heat treatment furnace 12 of the present invention includes a heat treatment space composed of a furnace ceiling 13, a furnace wall 14, and a hearth 15, a heater 3 for heating a workpiece (not shown), The heater holding structure 1 holds the heater 3. Moreover, the gas supply pipe | tube 17 which supplies atmospheric gas to heat processing space, and the gas exhaust pipe 18 which exhausts exhaust gas from heat processing space are provided.
[0020]
The heat treatment furnace main body 12a includes a furnace ceiling 13, a furnace wall 14, and a heat insulating material 16 provided on the heat treatment space side. A heater insertion port 13 a for inserting the heater 3 is formed in the furnace ceiling 13. Moreover, you may provide the insertion port of the gas supply pipe | tube 17, and the insertion port of the gas exhaust pipe | tube 18 as needed.
[0021]
The hearth 15 is made of a heat insulating material 16 and can be rotated and driven up and down by a driving means (not shown).
[0022]
The gas supply pipe 17 is provided substantially vertically from the furnace ceiling 13 in parallel with the heater 3. The material is made of ceramic such as alumina, and a plurality of atmosphere gas supply holes (not shown) are formed on the side surface of the workpiece.
[0023]
The gas exhaust pipe 18 is for exhausting the exhaust gas burned in the heat treatment space to the outside of the heat treatment space, and is provided at the approximate center of the furnace ceiling 13.
[0024]
Further, the heater holding structure 1 is the same as that described above, and a description thereof will be omitted.
[0025]
Although the batch type heat treatment furnace is described here as an embodiment, it may be a continuous heat treatment furnace.
[0026]
【The invention's effect】
The heater holding structure of the present invention includes a rod-shaped heater having a through hole formed in the vicinity of one end thereof, a heater holding pin inserted into the through hole of the heater and having a length larger than the outer diameter of the heater, and a furnace ceiling. A heater holding tube that is installed so as to cover the provided heater insertion opening and inserts the heater inside to hold the heater holding pin, and a pin fall-off prevention tool, and the heater is inserted into the heater holding tube. The heater holding pin inserted in the through hole of the heater is hooked on the upper surface of the heater holding pipe, the heater is suspended from the furnace ceiling, and a pin drop prevention tool is put on the outside of the heater holding pin and the heater holding pipe. The heater is held substantially vertically downward from the furnace ceiling of the heat treatment furnace.
[0027]
By adopting such a configuration, it is possible to prevent the heater holding pin from falling off the heater, so there is no need to bend the heater holding pin itself and fix it to the heater holding tube, and the heater holding pin has excellent heat resistance and insulation. Ceramic or the like can be used. Furthermore, since it is not necessary to deform the heater holding pin, it can be used repeatedly.
[0028]
The heat treatment furnace of the present invention has a heat treatment space composed of a furnace ceiling, a furnace wall, and a hearth, and the heater is inserted and held in the heat treatment space using the heater holding structure. Therefore, it is possible to provide a heat treatment furnace having a long heater holding structure and no risk of short circuit or electric leakage.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing a heater holding structure which is a reference of the present invention.
FIG. 2 is an exploded perspective view showing a heater holding structure which is a reference of the present invention.
FIG. 3 is a perspective view showing a latching portion of a heater holding pipe which is a reference of the present invention.
FIG. 4 is a schematic sectional view showing a heater holding structure of the present invention.
FIG. 5 is an exploded perspective view showing a heater holding structure of the present invention.
FIG. 6 is a schematic sectional view showing a heat treatment furnace of the present invention.
FIG. 7 is a schematic sectional view showing a conventional heater holding structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Heater holding structure 3 Heater 3a Through-hole 5 Heater holding pin 7 Heater holding pipe 7a Fixing part 7b Latching part 9 Pin fixing tool 11 Pin drop prevention tool 12 Heat treatment furnace 13 Furnace ceiling 13a Heater insertion port 14 Furnace wall 15 Furnace

Claims (2)

A heater holding structure that holds the heater in a substantially vertical downward direction from the furnace ceiling of the heat treatment furnace,
A rod-shaped heater having a through hole formed in the vicinity of one end thereof, a heater holding pin inserted into the through hole of the heater and having a length larger than the outer diameter of the heater, and a heater inserted in the furnace ceiling It is installed so as to cover the mouth, and includes a heater holding tube that inserts the heater inside and hooks the heater holding pin, and a pin drop prevention tool,
The heater is inserted into the heater holding tube, the heater holding pin inserted into the through hole of the heater is hooked on the upper surface of the heater holding tube, the heater is suspended from the furnace ceiling, and the heater A heater holding structure characterized in that a pin drop prevention tool is put on the outside of a holding pin and a heater holding tube. It has a heat treatment space composed of a furnace ceiling, a furnace wall, and a hearth,
A heat treatment furnace, wherein the heater is inserted and held in the heat treatment space using the heater holding structure according to claim 1.

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