JP2012225620A - Heat treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment device in which an atmospheric gas is preheated without an extra space or an additional heat source to uniformize a temperature of a gas contacting with a treated object, thereby inhibiting the unevenness heat treatment.SOLUTION: A gas supply pipe 19 for supplying the atmospheric gas includes: an inner pipe 27 having gas exhaust nozzles 30; and an outer pipe 28 provided outside the inner pipe 27 and having gas exhaust nozzles 31. The gas supply pipe 19 is constructed in such a manner that projected figures of outlines of the gas exhaust nozzles 30 when the gas exhaust nozzles 30 are perpendicularly projected to an inner wall surface of the outer pipe 28 do not interfere with the gas exhaust nozzles 31. The atmospheric gas introduced from the outside of a furnace body into the inner pipe 27 is thus preheated by a temperature in a furnace while passing through the inside of the inner pipe 27 and a clearance between the inner pipe 27 and the outer pipe 28. As a result, the atmospheric gas having a uniform temperature is supplied to the treated object 11.

Description

  The present invention relates to a heat treatment apparatus that performs a heat treatment with supply of an atmospheric gas to an object to be processed conveyed inside a furnace body.

  Conventionally, heat treatment with supply of atmospheric gas to an object to be processed has been widely performed. For example, heat treatment for applying paste to a glass substrate such as a liquid crystal panel, plasma display panel, or solar cell panel and drying or firing, heat treatment for firing electronic components such as ceramic capacitors, or synthesis involving chemical reaction Alternatively, for the purpose of particle growth or the like, there is a heat treatment for firing a powder made of a metal material or an inorganic material.

  A batch-type small furnace is widely used as an apparatus for heat-treating a small amount of workpieces on a laboratory scale. On the other hand, a continuous conveyance type large furnace is widely used as an apparatus for continuously heat-treating a large amount of workpieces. The continuous conveyance type apparatus is classified into several types according to the conveyance method of the workpiece.

  In some cases, the object to be processed is placed directly on the transport medium and directly transported, or is often transported by being loaded on a plate-like or box-shaped stacking member. For example, when the object to be processed is a glass substrate or the like, a plate-like stacking member having the same degree of hardness as glass is widely used in order to prevent the substrate from being cracked or scratched. When the material to be processed is powder, the amount of powder loaded with high fluidity (that is, the amount of powder heat treated at one time) is controlled to some extent while preventing the powder from adhering to the components of the furnace. In order to ensure, a box-shaped stacking member is widely used. A hydraulic pusher (pusher furnace), a ceramic roller conveyor (roller hearth furnace), a metal mesh belt conveyor (mesh belt furnace), or the like is used as a conveyance medium for the workpiece and the stacking member.

  When heat treatment of a workpiece is continuously performed, an atmospheric gas necessary for desired heat treatment including a chemical reaction is often continuously supplied to the workpiece. The major problem in supplying atmospheric gas to the object to be processed is that the amount of heat applied to the object to be processed and the degree of contact with the atmospheric gas necessary for the reaction vary depending on the location, and this is different for each location. The difference in heat treatment state, that is, heat treatment unevenness is caused. In general, excessive heat treatment unevenness causes performance deterioration of various products manufactured using the processed object after heat treatment, and thus it is strongly required to suppress heat treatment unevenness.

  In many cases, the atmospheric gas is at a room temperature outside the furnace, and the temperature inside the furnace (that is, from a heated furnace body or a member / heating element existing in the furnace) is introduced into the furnace. After being heated by the heat transferred, it is supplied to the object to be processed. Therefore, if the atmospheric gas is not sufficiently heated on the way and is supplied to the object to be processed as a low-temperature atmosphere gas, temperature unevenness occurs in the object to be processed, which causes a large heat treatment unevenness.

  As a conventional method for supplying atmospheric gas for the purpose of suppressing unevenness in heat treatment, the gas introduced from the ceiling of the furnace is retained in the upper space in the furnace and preheated, and then processed through a perforated plate. A method of supplying the product has been proposed (see, for example, Patent Document 1).

  FIG. 7 is a cross-sectional view showing a configuration of a conventional heat treatment apparatus described in Patent Document 1 in the previous period, and a conveying direction of a stacking member 2 on which workpieces 1 are stacked (direction perpendicular to the paper surface of FIG. 7). The cross section which cut | disconnected the furnace body 3 by the surface perpendicular | vertical to is shown. The stacking member 2 on which the workpiece 1 is loaded is heat-treated while being transported in the furnace by the transport roller 4.

  As shown in FIG. 7, a perforated ceiling plate 5 in which a large number of gas flow holes are formed over the entire surface is disposed horizontally in the upper space of the transport roller 4 in the furnace body 3. Is divided into a ceiling chamber 6 above the perforated ceiling plate 5 and a furnace chamber 7 below the perforated ceiling plate 5. A gas supply pipe 8 is provided through the ceiling wall of the furnace body 3, and its lower end communicates with the ceiling chamber 6. With this configuration, the atmospheric gas once stays in the ceiling chamber 6, is preheated by the furnace temperature, and then is supplied into the furnace chamber 7 through the gas flow holes of the perforated ceiling plate 5. Patent Document 1 describes the effect of reducing temperature unevenness at each place when the atmospheric gas comes into contact with the workpiece 1 by preheating and suppressing heat treatment unevenness.

JP 2010-223563 A

  However, in the conventional configuration, since it is necessary to provide a space for preheating the gas in the furnace, it is necessary to increase the volume in the furnace. This leads to an increase in the size of the furnace body 3, which in turn increases equipment costs. In addition, when the volume in the furnace increases, an equivalent amount of atmospheric gas is required, and the cost required to purchase or generate the atmospheric gas and the energy cost for heating the atmospheric gas in the furnace also increase. Thus, the configuration described in Patent Document 1 still has room for improvement in terms of economy.

  As a method of preheating the atmospheric gas without providing a space for preheating the gas in the furnace, a heat source different from the heat source normally provided in the furnace to control the temperature distribution in the furnace Is provided outside the furnace and heated before introducing the gas into the furnace. However, in such a method, additional space and cost are required to provide a heat source and its control device outside the furnace. In addition, the higher the temperature used for the heat treatment, the more difficult it is to preheat the gas to a predetermined temperature outside the furnace, and heat is dissipated from the heat source added outside the furnace to the surroundings, resulting in energy consumption. Cost will increase significantly.

  Due to the problems described above, the conventional heat treatment apparatus has a problem that it is difficult to preheat the atmospheric gas without requiring an extra space and an additional heat source.

  In view of the above-described conventional problems, the present invention, without requiring an extra space and an additional heat source, preheats the atmospheric gas and then ejects the gas into the furnace to equalize the temperature of the gas in contact with the workpiece. It aims at providing the heat processing apparatus which can implement | achieve suppression of the heat processing nonuniformity.

In order to achieve the above object, the heat treatment apparatus of the present invention comprises:
A heat treatment apparatus for performing a heat treatment involving supply of atmospheric gas to an object to be treated in a space surrounded by walls constituting the furnace body (hereinafter also referred to as “furnace interior”),
A heater for controlling the temperature distribution inside the furnace body;
A first gas supply pipe provided with a first gas jet port for jetting atmospheric gas along the first gas jet direction;
A second gas supply pipe provided outside the first gas supply pipe with a second gas jet port for jetting atmospheric gas along the second gas jet direction;
The projection when the outline of the first gas outlet is vertically projected on the inner wall surface of the second gas supply pipe does not interfere with the second gas outlet,
Atmospheric gas is introduced from the outside of the furnace body into the first gas supply pipe, and is ejected into the second gas supply pipe through the first gas outlet provided in the first gas supply pipe. Then, it is ejected from a second gas ejection port provided in the second supply pipe, and is supplied to an object to be processed inside the furnace body.
It is a heat treatment apparatus.

  According to the heat treatment apparatus of the present invention, after preheating the atmospheric gas without requiring an extra space and an additional heat source, the gas is sprayed into the furnace body to uniformize the temperature of the gas in contact with the object to be processed. Can be suppressed.

(A) Schematic sectional view perpendicular to the transfer direction of the heat treatment apparatus in Embodiment 1 of the present invention and perpendicular to the transfer surface (b) Parallel to the transfer direction of the heat treatment apparatus in Embodiment 1 of the present invention, and Schematic cross section perpendicular to the transfer surface The block diagram of the heat processing apparatus in Embodiment 1 of this invention (A) Side sectional view showing an example of the gas supply pipe of the heat treatment apparatus according to Embodiment 1 of the present invention (b) Perpendicular to the longitudinal direction showing an example of the gas supply pipe of the heat treatment apparatus according to Embodiment 1 of the present invention Sectional view (A) Perspective view showing an inner pipe (first gas supply pipe) which is one of the members constituting the gas supply pipe of the heat treatment apparatus in the first embodiment of the present invention. (B) In the first embodiment of the present invention. FIG. 4 is a perspective view showing an outer pipe (second gas supply pipe) which is one of the members constituting the gas supply pipe of the heat treatment apparatus; (c) of the members constituting the gas supply pipe of the heat treatment apparatus according to Embodiment 1 of the present invention. Perspective view showing one bush The figure which shows the outline of one structural example of the gas supply mechanism of the heat processing apparatus in Embodiment 1 of this invention. Schematic sectional view perpendicular to the transport direction and perpendicular to the transport surface of the heat treatment apparatus in Embodiment 2 of the present invention Schematic sectional view perpendicular to the conveying direction of the conventional heat treatment apparatus in Patent Document 1 and perpendicular to the conveying surface

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals, and description thereof is omitted as appropriate.

(Embodiment 1)
FIG. 1A is a schematic cross-sectional view perpendicular to the transport direction of the heat treatment apparatus 10 according to the first embodiment of the present invention and perpendicular to the transport surface, and FIG. 1B is the first embodiment of the present invention. 2 is a schematic cross-sectional view parallel to the transport direction of the heat treatment apparatus 10 and perpendicular to the transport surface. FIG. Here, the “conveyance direction” is a direction in which the object to be processed 11 travels, and the “conveyance surface” is a surface on which the object to be processed (or the stacking member 12 on which the object is loaded) is placed. . In general, the “transport surface” is a surface parallel to the ground contact surface of the heat treatment apparatus 10.

(About the overall configuration of the device)
The heat treatment apparatus 10 includes an object 11 to be processed, a loading member 12, a furnace body 13, an upper heat insulating wall 13a as an upper wall of the furnace body 13, a lower heat insulating wall 13b as a lower wall of the furnace body 13, and a furnace body. A side heat insulating wall 13c as a set of side walls that are perpendicular to the conveyance surface of the object 11 in the image 13 and are opposed to the left and right of the paper surface of FIG. 14, a zone partition 15, a passage port 16, an upper heater 17, a lower heater 18, a gas supply pipe 19, a gas outlet 20, a gas exhaust pipe 21, and a gas inlet 22.

  1 (a) and 1 (b), Dc is the transport direction of the stacking member 12, Dg is the gas ejection direction, Fv is a virtual surface having the same height as the surface layer surface of the workpiece 11, and θ is The angle formed by the perpendicular of the virtual plane Fv and the gas ejection direction Dg, h is the distance between the virtual plane Fv and the gas outlet 20, H is the vertical height of the furnace body 13, and L is the transport of the furnace body 13 The length along the direction Dc, W, indicates a dimension (width) in a direction perpendicular to the transport direction Dc of the furnace body 13 and parallel to the transport surface, which will be described later.

(About device operation)
The heat treatment apparatus 10 transports a box-shaped stacking member 12 loaded with a powder-like workpiece 11 inside a furnace body 13, and the internal space of the furnace body 13 (this space is referred to as “furnace in this specification”). This is an apparatus for heat-treating the workpiece 11 (sometimes referred to as “inside the body” or “inside the furnace”). In the first embodiment, as shown in FIG. 1 (b), the stacking member 12 is transported by the rotation of a plurality of transport rollers 14 installed in the horizontal direction (left and right direction in FIG. 1 (b)). Conveyed in the direction. In other words, the surface including the upper apex of the plurality of juxtaposed conveying rollers 14 becomes the conveying surface of the stacking member 12, and on this conveying surface, the stacking member 12 moves in the conveying direction Dc indicated by an arrow in FIG. Along (from the left to the right in FIG. 1B and from the front to the back in FIG. 1A).

  The stacking members 12 are arranged in rows along the transport direction Dc shown in FIG. 1B, and the workpieces 11 stacked on the stacking member 12 are continuously transported by continuously transporting them. Heat treatment can be performed. The stacking members 12 may be arranged at a certain interval in order to avoid a collision between the stacking members 12 or may be arranged without a gap.

(Regarding the conveying method of the stacking member 12)
With reference to FIG. 1A, a method of conveying the stacking member 12 will be further described. The stacking member 12 is transported from the front side to the back side in FIG. 1A, and here, three stacking members 12 are juxtaposed in the lateral direction perpendicular to the transport direction (left and right direction in FIG. 1A). Shows the case. In this way, the three stacking members 12 are juxtaposed in the lateral direction (the direction perpendicular to the transport direction and parallel to the transport surface), and transported at the same time, so that the three stacks juxtaposed in the lateral direction. The workpieces 11 loaded on the member 12 can be simultaneously heat-treated. As described above, since the stacking members 12 are arranged in rows along the transport direction, here, the stacking members 12 in three rows are transported continuously at the same time. Of course, the number of the stacking members 12 juxtaposed in the lateral direction is not limited to this. The productivity increases as the number of stacking members 12 juxtaposed in the lateral direction increases, but the installation space for the apparatus increases, and the difficulty of carrying and the difficulty of performing uniform heat treatment in the lateral direction also increase.

  In FIG. 1 (a), the gaps between the three stacking members 12 juxtaposed in the lateral direction are 50 [mm] in the lateral direction, respectively, and the gaps between the stacking members 12 and the furnace inner wall surface are both horizontal. 150 [mm] in the direction. Of course, the size of the gap is not limited to this, but the larger the gap, the larger the installation space of the apparatus. Therefore, it is desirable to set an appropriate gap.

(About the heat insulation wall of the furnace body 13)
Then, the heat insulation wall of the furnace body 13 is demonstrated. As shown in FIG. 1 (a), an upper heat insulating wall 13a as an upper wall of the furnace body 13 and a lower heat insulating wall 13b as a lower wall of the furnace body 13 are opposed side walls that define the horizontal dimension of the furnace body 13. Side heat insulating walls 13c are respectively provided.

(Regarding the zone configuration of the heat treatment apparatus 10)
Next, the zone configuration of the heat treatment apparatus 10 will be described. In the furnace body 13 of the heat treatment apparatus 10, the internal space (that is, the inside of the furnace) is divided into a plurality of heat treatment zones (treatment spaces) along the transport direction Dc. In each zone, heat treatment according to the heat treatment process is performed. FIG. 1B shows a cross section of one of them. Each zone is partitioned by a zone partition 15, and the zone partition 15 is provided with a passage port 16 through which the workpiece 11 and the stacking member 12 can pass.

(About dimensions of furnace body 13)
In the first embodiment, the dimension of the furnace body 13 is the dimension (that is, height) H in the direction perpendicular to the transport surface (also referred to as “vertical direction” in the present specification including the following description). The length L along the transport direction Dc of each zone is set to 1000 [mm] and 1500 [mm]. A direction perpendicular to the conveyance direction Dc and parallel to the conveyance surface (in this specification including the following description, a direction parallel to the conveyance surface is also referred to as a “horizontal direction”, orthogonal to the conveyance direction Dc, and , The width W is 1800 [mm]. Of course, the dimension is not limited to this, and is appropriately selected according to the processing amount of the workpiece 11.

(About the shape of the stacking member 12)
Next, the shape of the stacking member 12 will be described. As shown in FIGS. 1A and 1B, here, a box-shaped container having a square bottom surface is used as the stacking member 12. Of course, the shape of the stacking member 12 is not particularly limited, and for example, a cylindrical container having a circular bottom surface and an open top, a plate-like one without a border, and the like can be used. However, if a plate-shaped stacking member without a border is used in conveying highly fluid powder, the amount of powder that can be loaded on one stacking member is limited and the productivity is reduced. It is desirable to use some box-type container.

  Further, in the first embodiment, an example is shown in which the powdery object to be processed 11 is loaded on the box-shaped stacking member 12 and heat-treated, but of course the forms of the object to be processed 11 and the stacking member 12 are as follows. It is not limited to this. For example, the object to be processed may be composed of a glass substrate coated with a paste. In that case, the object to be processed is loaded on, for example, a plate-shaped stacking member and subjected to heat treatment. The present invention can also be applied to an apparatus for heat-treating such an object to be processed.

(Conveying roller 14)
Next, the conveyance roller 14 will be described. The material and thickness of the conveyance roller 14 are selected so that the conveyance roller 14 has a strength that can withstand the load of the stacking member 12 on which the workpiece 11 is loaded. Further, the transport rollers 14 are arranged at a pitch sufficiently shorter than the dimension of the stack member 12 in the transport direction Dc so that the stack member 12 does not fall. If the transport roller 14 is too thick or the pitch at which the transport rollers 14 are arranged is too small, heat transfer from the lower heater 18 located below the transport path, which will be described later, is hindered by the transport roller 14. It is desirable to select the pitch. Of course, the conveying method is not limited to the method of conveying the stacking member 12 by the rotation of the conveying roller 14, for example, a method of pushing the stacking member 12 on the roller with a hydraulic pusher, a method of conveying with a mesh belt conveyor, etc. Can be used. When these methods are employed, a transfer device or a transfer medium corresponding to the method is provided in the heat treatment apparatus 10.

(Materials of the stacking member 12 and the transport roller 14)
Subsequently, materials of the stacking member 12 and the transport roller 14 will be described. Here, alumina ceramics are used as the material of the stacking member 12 and the transport roller 14. Of course, as long as the heat resistance and strength at the operating temperature are satisfied, for example, zirconia ceramics and metal such as SUS and Inconel can be used. However, when the object 11 is highly corrosive, the surfaces of the stacking member 12 and the transport roller 14 are corroded and separated by the loaded object 11 and the scattered object 11, and the object 11 is processed. There is a risk of contamination as impurities. Therefore, it is desirable that the material of the stacking member 12 and the transport roller 14 has corrosion resistance.

(About the heater)
Then, the heater which controls the temperature distribution inside the furnace body 13 to the temperature distribution according to the heat treatment process will be described. In the first embodiment, a plurality of upper heaters 17 and a plurality of lower heaters 18 are provided as heaters in the vertical direction across the conveyance path of the stacking member 12. Specifically, in the zone shown in FIG. 1B, four cylindrical upper heaters 17 are arranged along the transport direction Dc above the transport roller 14 (on the side of the upper heat insulating wall 13a). Four cylindrical lower heaters 18 are arranged below the roller 14 (on the side of the lower heat insulating wall 13b) along the transport direction Dc. Further, the upper heater 17 and the lower heater 18 are arranged so that the longitudinal direction thereof is parallel to the horizontal direction (the left-right direction in FIG. 1A).

  As described above, by arranging the heaters above and below the conveying roller 14 respectively, the vertical direction (front and back) of the workpiece 11 and the stacking member 12 is higher than when the heaters are arranged only on one side. Thermal property can be improved. In addition, in order to further improve the heat uniformity in the vertical direction (front and back surfaces) of the workpiece 11 and the stacking member 12, the upper heater 17 and the lower heater 18 are arranged vertically between each of them and the stacking member 12. It is preferable to arrange them so that the distances in the directions (vertical direction in FIG. 1B) are equal.

  Here, the upper heater 17 and the lower heater 18 have the same shape, but may have different shapes as long as the upper and lower temperature distribution control is taken into consideration. Further, the upper heater 17 and the lower heater 18 may be embedded in, for example, the upper heat insulating wall 13a and the lower heat insulating wall 13b constituting the furnace body 13. When the heater is embedded in the heat insulating wall, the thermal efficiency is lowered, but the heat treatment apparatus 10 can be downsized.

  Here, as the types of the upper heater 17 and the lower heater 18, an electric heater using a cylindrical ceramic itself as a heating element is used, but the types of heaters (upper heater 17 and lower heater 18) are the same. It is not limited. For example, various heaters such as a panel-type electric heater, an oil circulation type or gas combustion type heater, or a heater using microwaves, electromagnetic waves, lasers, or the like can be used as the heater.

(Regarding the control mechanism of the heat treatment apparatus 10)
FIG. 2 is a block diagram of heat treatment apparatus 10 according to Embodiment 1 of the present invention.
The control mechanism of the heat treatment apparatus 10 includes a control device 23, a transfer controller 14a, a transfer sensor 14b, an upper heater temperature controller 17a, a lower heater temperature controller 18a, a gas supply source 24, and a gas flow rate adjustment unit. 25 and an exhaust flow rate adjusting unit 26.

(Regarding the control mechanism of the heater)
A control mechanism of the heater will be described. Here, the upper heater 17 and the lower heater 18 are connected to an upper heater temperature controller 17a and a lower heater temperature controller 18a, respectively, and these temperature controllers control the outputs of the upper heater 17 and the lower heater 18, that is, the temperatures. Control individually.

(Regarding the gas supply mechanism of the heat treatment apparatus 10)
Next, the gas supply mechanism of the heat treatment apparatus 10 will be described. When the heat treatment applied to the workpiece 11 involves a chemical reaction, it is necessary to supply the interior of the furnace body 13 with the kind of atmospheric gas necessary for the desired chemical reaction. Further, in the case of heat treatment that does not involve a chemical reaction but generates evaporative gas (for example, a process of evaporating the solvent and water contained in the object 11 to dry the object 11), the evaporating gas A gas exhaust mechanism that exhausts the atmosphere in the furnace including the outside of the furnace is required. In that case, in order to maintain the pressure balance in the furnace, it is necessary to supply an atmosphere gas having a flow rate comparable to the exhausted flow rate into the furnace body 13. In this Embodiment 1, since the to-be-processed object 11 is heat-processed with both a chemical reaction and generation | occurrence | production of evaporative gas, it is an atmosphere for two purposes, promotion of a chemical reaction and ensuring of the pressure balance in a furnace. Gas is supplied and oxygen (O ₂ ) is used as the atmospheric gas.

  The gas supply mechanism of the heat treatment apparatus 10 is a mechanism for supplying atmospheric gas to the inside of the furnace body 13 from the outside of the furnace body 13. Specifically, the atmosphere gas is supplied to the gas supply pipe 19 and the gas supply pipe 19. A gas supply source 24 to be supplied and a gas flow rate adjusting unit 25 for controlling the flow rate of the atmospheric gas supplied from the gas supply source 24 to the gas supply pipe 19 are provided. For the gas flow rate adjusting unit 25, for example, a regulator, a damper, a fan, a flow meter, a mass flow controller, or the like can be used.

(About the gas supply pipe 19 and the gas supply method)
Subsequently, the gas supply pipe 19 and the gas supply method will be further described with reference to FIGS. The gas supply pipe 19 is a part of a gas supply mechanism that supplies an atmosphere gas necessary for a desired heat treatment to the inside of the furnace body 13, and this gas supply pipe 19 is cylindrical and has a lateral direction (FIG. a) in the left-right direction of the paper surface) and penetrates the side heat insulating wall 13c. As shown in FIG. 2, the gas supply pipe 19 is connected to a gas supply source 24 that is a part of the gas supply mechanism outside the furnace body 13. The gas supply pipe 19 is provided with a gas flow rate adjusting unit 25 that is a part of the gas supply mechanism outside the furnace body 13. Further, as shown in FIG. 1B, the position of the gas supply pipe 19 inside the furnace body 13 is above the conveyance path (conveyance roller 14) of the stacking member 12. In order to avoid interference with the upper heater 17 described above, it is desirable that the gas supply pipe 19 be installed in parallel with the upper heater 17.

  Usually, ambient gas at room temperature (room temperature) is supplied from the gas supply source 24, and the ambient gas is heated by the furnace temperature controlled by the heater described above while passing through the inside of the gas supply pipe 19. Then, the workpiece 11 and the stacking member 12 are supplied to the internal space of the furnace body 13 in which the workpiece 11 and the stacking member 12 are transported. However, if the atmospheric gas is not sufficiently warmed while passing through the inside of the gas supply pipe 19 and is supplied to the object to be processed 11 at a low temperature, the object to be processed 11 has a large temperature unevenness. It causes heat treatment unevenness. In order to prevent this, the gas supply pipe 19 according to the first embodiment has a configuration described below.

(Regarding the configuration for gas preheating provided in the gas supply pipe 19)
FIGS. 3A and 3B are diagrams showing details of the gas supply pipe 19 of the heat treatment apparatus 10 according to the first embodiment. 3A is a side sectional view of the gas supply pipe 19 cut in the longitudinal direction, and FIG. 3B is a sectional view perpendicular to the longitudinal direction of the gas supply pipe 19.

(Detailed configuration of the gas supply pipe 19)
The gas supply pipe 19 is inserted into a gap between the inner pipe 27 corresponding to the first gas supply pipe, the outer pipe 28 corresponding to the second gas supply pipe disposed outside the inner pipe 27, and the inner pipe 27 and the outer pipe 28. And a bush 29. The inner pipe 27 is provided with inner pipe gas outlets 30a to 30e, which are first gas outlets, on its side surface, and the outer pipe 28 is provided with outer pipe gas jets, which are second gas outlets, on its side face. Exits 31a-f are provided. 1A corresponds to the outer tube gas outlets 31a to 31f in FIG. 3A.
3 (a) and 3 (b), Di represents the first gas ejection direction, the inner tube gas ejection direction, and Do represents the second gas ejection direction, the outer tube gas ejection direction, respectively. These will be described later.

(Regarding members constituting the gas supply pipe 19)
FIGS. 4A to 4C are views individually showing members constituting the gas supply pipe 19. 4A is a perspective view of the inner tube 27, FIG. 4B is a perspective view of the outer tube 28, and FIG. 4C is a perspective view of the bush 29.
The inner tube 27 is formed of a cylindrical tube, and an inner tube gas outlet 30 (specifically, a plurality of inner tube gas outlets 30a to 30e) is formed on a side surface of the tube. The outer tube 28 is formed of a cylindrical tube, and an outer tube gas ejection port 31 (specifically, a plurality of outer tube gas ejection ports 31a to 31f) is provided on a side surface of the tube. The bush 29 is a cylindrical member.

(About the diameter and thickness of the inner tube 27 and the outer tube 28)
Here, the inner diameter of the inner tube 27 was 16 [mm], the inner diameter of the outer tube 28 was 30 [mm], and the thickness of each tube was 3 [mm]. Of course, the diameter of the gas supply pipe is not limited to this, but the inner pipe 27 and the outer pipe when the inner pipe 27 and the outer pipe 28 are combined as shown in FIGS. 3 (a) and 3 (b). It is desirable to select the diameter and thickness of each pipe so that the 28 gaps are at least 2 [mm] in the diameter direction. In general, the gap preferably has a distance of 5 to 20% of the inner diameter of the outer tube 28 in the diametrical direction. If the gap is too small, the gas flow path between the inner tube 27 and the outer tube 28 becomes narrow, so that the pressure loss and the flow velocity in the tube become excessive, and proper gas supply may not be performed. Further, if the gap is too large, the inner diameter of the inner tube 27 must be set to be considerably small, and the gas flow path in the inner tube 27 becomes narrow, and the same problem may occur.

(About Bush 29)
As shown in FIG. 3A, a cylindrical bush 29 having an inner diameter of 22 [mm] and a thickness of 4 [mm] is inserted into the end portion of the inner tube 27 in the gap between the inner tube 27 and the outer tube 28. The space of the gap formed between the inner tube 27 and the outer tube 28 is blocked from the outside of the furnace body 13 by the bush 29. Therefore, the atmospheric gas supplied from the outside of the furnace body 13 is first introduced only into the inner tube 27.

(About the route through which atmospheric gas passes)
As shown in FIG. 3 (a), a plurality of inner tube gas ejection ports 30 are provided on the side surface of the inner tube 27 inside the furnace body 13. The inner tube gas outlet 30 is a through hole that allows the inside and the outside of the inner tube 27 to communicate spatially. Therefore, the atmospheric gas introduced from the outside of the furnace body 13 into the inner tube 27 is ejected in the inner tube gas ejection direction Di through the inner tube gas ejection port 30 and introduced into the outer tube 28. A plurality of outer tube gas ejection ports 31 are provided on the side surface of the outer tube 28 inside the furnace body 13. The outer pipe gas ejection port 31 is a through hole that spatially communicates the inside and the outside of the outer pipe 28. Accordingly, the atmospheric gas introduced from the inside of the inner pipe 27 into the outer pipe 28 is ejected in the outer pipe gas ejection direction Do through the outer pipe gas ejection port 31. The outer tube gas ejection direction Do here corresponds to the gas ejection direction Dg shown in FIG. 1A, and the atmospheric gas ejected in the gas ejection direction Dg in FIG. The member 12 is supplied to the internal space of the furnace body 13 in which the member 12 is conveyed.

  In the first embodiment, the inner tube gas ejection direction Di and the outer tube gas ejection direction Do are different from each other. However, even if Di and Do are the same, the projection when the contour of the inner tube gas outlet 30 is vertically projected onto the inner wall surface of the outer tube 28 interferes with the outer tube gas outlet 31 as will be described later. As long as this is not done, the effect of the present invention (atmospheric gas preheating effect) can be obtained.

(Regarding the effect of preheating atmospheric gas)
With the above configuration, the atmospheric gas is heated by the furnace temperature while passing through the inside of the inner tube 27 and the inside of the outer tube 28. Therefore, the gas supply pipe 19 having this configuration is supplied to the internal space of the furnace body 13 in a state in which the atmospheric gas is heated more than a gas supply pipe having a single pipe structure that does not have a further pipe inside or outside thereof. Makes it possible to In particular, the gas supply pipe 19 having this configuration is such that the ambient gas is ejected at a low temperature at the outer pipe gas outlet 31 located at a position close to the outside of the furnace body 13 (a position where the gas heating path is short). It is possible to suppress heat treatment unevenness of the workpiece 11.

  Further, in the heat treatment apparatus 10 having the gas supply pipe 19 having this structure, as shown in Patent Document 1, atmospheric gas introduced from the ceiling of the furnace body 13 is retained in the upper space in the furnace and preheated. Compared to the conventional method of supplying the processed material 11, it is not necessary to provide an extra space for gas preheating in the furnace, so the furnace body 13 can be reduced in size and the equipment cost can be reduced. In addition, since the surface area of the furnace is reduced by downsizing the furnace body 13, the heat radiation from the outer wall surface of the furnace can be reduced, and the energy cost for maintaining the furnace temperature can be reduced. In addition, since the volume of the atmosphere gas to be used can be reduced by reducing the furnace volume due to the downsizing of the furnace body 13, the cost for purchasing or generating the atmosphere gas, and heating the atmosphere gas in the furnace The energy cost for doing so can be reduced.

(About the gas ejection direction with respect to the to-be-processed object 11)
Then, the gas ejection direction with respect to the to-be-processed object 11 is demonstrated in detail. In the first embodiment, as shown in FIGS. 1A and 1B, the atmospheric gas is ejected from the gas ejection port 20 toward the workpiece 11. An example of the gas ejection direction Dg is indicated by an arrow in FIG. Here, the gas ejection direction Dg is set so that the angle θ formed by the perpendicular of the virtual surface Fv having the same height as the surface of the workpiece 11 and the gas ejection direction Dg is 45 °. Of course, the angle θ is not limited to this. For example, the gas ejection direction Dg may be set so that θ is 0 °, and the ambient gas may be ejected perpendicular to the surface layer surface of the workpiece 11. However, since the flow path of the atmospheric gas in the furnace is preferably at an angle with the transport direction Dc (that is, not parallel to Dc), the gas ejection direction Dg is in the range of 0 ° ≦ θ <90 °, In addition, it is desirable to set the gas so that it does not collide with other members in the furnace such as the upper heater 17 as much as possible before the atmospheric gas after jetting hits the workpiece 11. This gas ejection direction Dg corresponds to the outer tube gas ejection direction Do in FIG.

(Relationship between inner tube gas outlet 30 and outer tube gas outlet 31)
The shapes, dimensions, and directions and positions of the inner tube gas jet port 30 and the outer tube gas jet port 31 are determined from the contour of the inner tube gas jet port 30 in the outer tube gas supply pipe 28. The projection when vertically projected on the wall surface is selected so as not to interfere with the outer tube gas outlet 31. In the vertical projection, the line segment connecting the outline of the inner tube gas outlet 30 and the inner wall of the outer tube 28 becomes a perpendicular to the inner wall surface (that is, the line segment, the line segment, and the inner wall). Project so that the tangent line at the intersection of The vertical projection on the inner wall surface of the outer pipe gas supply pipe of the inner pipe gas outlet 30 interferes with the outer pipe gas outlet 31. The outline of the projection and the inside of the projection are the gas outlet provided in the outer pipe. It means to overlap with 31. Therefore, on the inner wall surface of the outer tube 28, the contour of the gas nozzle 20 of the inner tube 27 can be vertically projected on the region of the inner wall surface where the outer tube gas nozzle 31 does not exist.

  When the vertical projection of the inner pipe gas outlet 30 interferes with the outer pipe gas outlet 31, a part and / or all of the inner pipe gas outlet 30 passes through the gap between the inner pipe 27 and the outer pipe 28. Facing the outer tube gas outlet 31. In that case, the atmospheric gas ejected from the inner tube gas ejection port 30 is ejected from the outer tube gas ejection port 31 without passing through a sufficiently long path between the inner tube 27 and the outer tube 28. That is, the effect of preheating the atmospheric gas cannot be obtained sufficiently. In order to avoid such inconvenience, in the present invention, the inner tube gas ejection direction Di and the outer tube gas ejection direction Do are made different from each other, or the longitudinal coordinates of the inner tube gas ejection port 30 and the outer tube gas ejection direction Do. The coordinates of the outlet 31 in the longitudinal direction are different from each other.

(Regarding the relationship between the gas ejection directions of the inner tube 27 and the outer tube 28)
Next, the relationship between the gas ejection directions of the inner tube 27 and the outer tube 28 will be described in detail. In the first embodiment, as shown in FIGS. 3A and 3B, the inner pipe gas ejection direction Di is a direction opposite to the outer pipe gas ejection direction Do, that is, the inner pipe gas ejection direction Di and the outer side. The tube gas ejection direction Do is set to be in a straight line and form an angle of 180 degrees. As a result, the atmospheric gas jetted from the inner pipe gas outlet 30 into the outer pipe 28 reaches the outer pipe gas outlet 31 so as to wrap around the outer periphery of the inner pipe 27 as shown in FIG. Accordingly, since the atmospheric gas passes through a longer path and is supplied from the outer tube gas outlet 31 to the heat treatment zone in the furnace, the effect of preheating the gas can be enhanced.

  Of course, the inner tube gas ejection direction Di is not limited to being exactly opposite to the outer tube gas ejection direction Do, and is preferably at least a direction different from the outer tube gas ejection direction Do. For example, the inner tube gas ejection direction Di and the outer tube gas ejection direction Do are, for example, such that the inner tube gas ejection direction Di and the outer tube gas ejection direction Do form an angle of 90 to 270 degrees. 27 and outer tube 28 may be arranged. If the angle is within this range, a good gas preheating effect can be obtained. Alternatively, the inner pipe gas outlet 30 and the outer pipe gas outlet 31 are provided so that their longitudinal coordinates are different from each other, whereby the contour of the inner pipe gas outlet 30 is perpendicular to the inner wall surface of the outer pipe 28. As long as the projection view and the outer tube gas ejection port 31 do not interfere with each other, the inner tube gas ejection direction Di may be the same as the outer tube gas ejection direction Do.

(Regarding the arrangement of gas outlets)
Then, arrangement | positioning of a gas jet nozzle is demonstrated in detail using FIG. 3 (a), FIG. 4 (a), and (b). In the first embodiment, as shown in FIG. 4B, six circular outer tube gas jets having a diameter of 12 [mm] are formed on the side surface of the cylindrical outer tube 28 inside the furnace body 13. The outlets 31a, 31b, 31c, 31d, 31e, and 31f are provided at a pitch of 180 [mm], respectively. As shown in FIG. 4 (a), on the side surface of the cylindrical inner tube 27 inside the furnace body 13, five circular inner tube gas outlets 30a, 30b, 30c having a diameter of 12 [mm] are provided. 30d and 30e are provided at a pitch of 180 [mm]. As shown in FIG. 3A, the coordinates of the center of the inner pipe gas outlet 30a in the longitudinal direction of the pipe (the coordinates of the y axis in FIG. 3A) are the center and outer side of the outer pipe gas outlet 31a. It arrange | positions so that it may correspond with the y coordinate of the midpoint of the line segment which ties the center of the pipe gas jet nozzle 31b. Similarly, in the other four inner pipe gas outlets 30b to 30e, the y coordinate of the center thereof coincides with the y coordinate of the midpoint of the line segment connecting the centers of the two adjacent outer pipe gas outlets 31. Are arranged.

  By arranging the inner pipe gas outlet 30 and the outer pipe gas outlet 31 in this manner, the atmospheric gas jetted from the inner pipe gas outlet 30 into the outer pipe 28 reaches the outer pipe gas outlet 31. The route to can be lengthened. Therefore, according to this arrangement, when the inner tube gas ejection direction Di and the outer tube gas ejection direction Do are different, the y coordinate of the center of the inner tube gas ejection port 30 and the center of the outer tube gas ejection port 31 are different. The effect of preheating the gas can be further enhanced as compared with the case where the y coordinate is matched. Of course, the arrangement of the inner tube gas outlet 30 is not limited to this. As long as the vertical projection on the inner wall surface of the outer pipe gas supply pipe 28 in the outline of the inner pipe gas outlet 30 does not interfere with the outer pipe gas outlet 31, the y coordinate of the center of the inner pipe gas outlet 30 is Even if it is arranged so as to be different from the y-coordinate of the center of the tube gas jet port 31, it is possible to obtain a gas preheating effect. On the other hand, even if the center of the inner pipe gas outlet 30 coincides with the y coordinate of the midpoint of the line segment connecting the centers of two adjacent outer pipe gas outlets 31, the inner pipe gas outlet 30 is large. When the vertical projection of the contour interferes with the outer tube gas jet port 31, the effect of the present invention cannot be obtained.

  In FIG. 1 (a), atmospheric gas is evenly applied to the objects to be processed 11 loaded on a plurality of stacking members 12 juxtaposed in the horizontal direction of the furnace body 13 (left and right direction in FIG. 1 (a)). In order to supply, it is desirable that the gas outlets 20 (that is, the outer tube gas outlets 31) be arranged uniformly over the entire area of the furnace body 13 where the workpiece 11 is present. On the other hand, the inner tube gas ejection ports 30 do not necessarily need to be arranged uniformly in the entire area of the inner tube 27 where the workpiece 11 exists in the lateral direction of the furnace body 13. For example, it is possible to arrange only one inner tube gas outlet 30 near the center in the horizontal direction of the furnace body 13 or to concentrate a plurality of inner tube gas outlets 30. In this case, the atmospheric gas introduced from the outside of the furnace body 13 can have a longer path until it reaches the inner pipe gas outlet 30 closest to the side heat insulating wall 13c, thereby enhancing the effect of preheating the gas. it can. However, when the inner tube gas outlet 30 is arranged in this way, the gas ejection from the inside of the inner tube 27 to the inside of the outer tube 28 in FIG. 3A is concentrated near the center in the lateral direction of the furnace body 13. Thereby, the subsequent gas ejection from the outer tube gas ejection port 31 is also concentrated near the center in the lateral direction of the furnace body 13. As a result, the atmospheric gas cannot be evenly supplied to the objects to be processed 11 stacked on the plurality of stacking members 12 juxtaposed in the horizontal direction in FIG. Therefore, as in the first embodiment, it is desirable that the plurality of inner tube gas outlets 30 be arranged uniformly in the lateral direction of the furnace body 13, that is, as shown in FIG.

  In order to achieve both the above-described sufficient preheating of the atmospheric gas and the supply of an equal amount of gas to each object 11, the side heat insulating walls 13 c on both sides of the plurality of outer tube gas outlets 31 are provided. When the region between the two outer pipe gas outlets 31a and 31f located closest to each other is divided into three equal parts in the longitudinal direction of the gas supply pipe 19, the inner pipe gas outlet 30 is divided into three equal parts. It is desirable to arrange at least one in each of the areas.

(About the material of the gas supply pipe)
Subsequently, the material of the gas supply pipe 19 will be described. In the first embodiment, as the material of the inner tube 27 and the outer tube 28, alumina ceramics having heat resistance and having corrosion resistance against the workpiece 11, the atmospheric gas, and the evaporation gas is used. The material of the gas supply pipe 19 is appropriately selected according to the type of the object 11 to be processed, the atmospheric gas, and the evaporating gas. On the other hand, materials other than alumina ceramics can be used as long as they have corrosion resistance. However, in order to enhance the effect that the atmospheric gas is preheated while passing through the inside of the inner pipe 27, the emissivity of the material surface used for the gas supply pipe 19 is important.

  The gas supply pipe 19 (that is, the outer pipe 28) shown in FIG. 1 is maintained in a state close to the furnace temperature by heat transfer from the furnace atmosphere whose temperature is controlled by the upper heater 17. However, since the inner pipe 27 inside the gas supply pipe 19 is not in contact with the temperature-controlled furnace atmosphere, the supply pipe itself is cooled by being deprived of heat by the atmospheric gas introduced at room temperature. there is a possibility. In order to prevent this, it is effective to keep the temperature of the inner tube 27 high by radiant heat from the inner surface of the outer tube 28 to the outer surface of the inner tube 27. Therefore, it is desirable to select a material having a surface emissivity of 0.5 or more as the material of the inner tube 27 and the outer tube 28. If the emissivity is less than 0.5, the radiant heat from the inner surface of the outer tube 28 to the outer surface of the inner tube 27 will be small, and the inner tube will be in a cold state and the effect of preheating the atmospheric gas cannot be sufficiently obtained. There is. In the first embodiment, alumina ceramics having a radiation rate of 0.8 is used as the material of the inner tube 27 and the outer tube 28.

(Conditions regarding the configuration of the gas supply pipe)
The conditions relating to the configuration of the gas supply pipe described above are introduced into the arrangement and number of the gas outlets 30 and 31, the gas jetting direction, the material of the gas supply pipe, and the gas supply pipe by numerical analysis under various conditions by the inventors. This is a condition found by variously changing the gas flow rate and obtaining the distribution of the temperature and flow rate of the atmospheric gas ejected from the plurality of outer tube gas ejection ports 31. By using the above conditions, the atmospheric gas introduced from the outside of the furnace body 13 is sufficiently heated by the furnace temperature while passing through the inside of the inner tube 27 and the inside of the outer tube 28, and a plurality of outer tubes It is ejected from the gas outlet 31 at a uniform flow rate, and can be supplied evenly to each object to be processed 11 without causing temperature unevenness in the object to be processed 11.

(About the shape and role of bush 29)
Next, the shape and role of the bush 29 will be further described. In the first embodiment, as shown in FIG. 3A, a cylindrical bush 29 having an inner diameter of 22 [mm] and a thickness of 4 [mm] is provided at the end of the gas supply pipe 19 and the inner pipe 27 and the outer side. It is inserted into the gap between the tube 28. When the long and narrow pipes are supported at spaced points and the gaps are wide, the pipes bend in the vertical downward direction due to the weight of the pipes. Such deflection occurs in the inner tube 27 and the outer tube 28 of the furnace body 13. In the outer pipe 28 (that is, the gas supply pipe 19 in FIG. 1A), the deflection occurs between the side heat insulating walls 13c on both sides, whereas in the inner pipe 27, FIG. It occurs between the two bushes 29 shown in FIG. Further, since the inner tube 27 has a smaller diameter than the outer tube 28, the amount of deflection tends to be larger. Therefore, when the horizontal dimension of the furnace body 13 is large and the pipe is long, the gap between the inner pipe 27 and the outer pipe 28 near the center in the horizontal direction of the furnace body 13 is caused by the deflection of the inner pipe 27. It may be very small on the lower side (furnace side).

  The gap between the inner tube 27 and the outer tube 28 is also a flow path for the atmospheric gas. Therefore, when the gap becomes small near the center in the horizontal direction of the furnace body 13, it is sufficient from the outer tube gas outlet 31 located near the center in the horizontal direction of the furnace body 13 and disposed on the lower side (furnace floor side). The problem arises that an amount of atmospheric gas is not ejected. In order to prevent this, the end of the bush 29 supporting the inner tube 27 is arranged as close to the center of the furnace body 13 as possible, and the distance between the two points supporting the tube is shortened to reduce the amount of deflection. It is effective to do. In other words, it is desirable to set the length of the bush 29 as long as possible without interfering with the outer pipe gas ejection port 31. In the first embodiment, the length of the bush 29 is 400 [mm].

(Material of bush 29)
The material of the bush 29 can be appropriately selected from those that satisfy the heat resistance at the use temperature and have corrosion resistance against the object 11, the atmospheric gas, and the evaporation gas. In the first embodiment, the same alumina ceramics as the inner tube 27 and the outer tube 28 are used as the material of the bush 29 so as not to generate an excessive stress on the inner tube 27 and the outer tube 28 due to a difference in thermal expansion. Used.

(About the installation height of the gas supply pipe)
Next, the installation height of the gas supply pipe will be described. In the first embodiment, the gas is so set that the distance h between the virtual surface Fv having the same height as the surface layer surface of the workpiece 11 shown in FIG. 1B and the gas outlet 20 is 90 [mm]. The installation height of the supply pipe 19 is set. The longer the distance h is set, the longer the time from when the atmospheric gas is ejected from the gas outlet 20 until it reaches the object 11 to be processed, and during that time the atmospheric gas is heated by the furnace temperature. A tendency to reduce temperature unevenness when being supplied to the workpiece 11 can be obtained. However, the longer the distance h is set, the larger the internal space of the furnace body 13 is. Therefore, the supply amount of the atmospheric gas necessary for the heat treatment is further increased, and the cost for purchasing the atmospheric gas or generating the atmospheric gas, and the atmosphere. There is a disadvantage that the energy cost for heating the gas in the furnace is further increased. In order to prevent this, the distance h is preferably 300 [mm] or less, and more preferably 200 [mm] or less. When the distance h is 300 [mm] or more, the above-described cost becomes large, which is not economical.

(About multiple tubes)
In the first embodiment, an example of a double pipe constituted by the inner pipe 27 and the outer pipe 28 is shown as the configuration of the gas supply pipe. However, one or more pipes are further provided outside the outer pipe 28. Further, a tube having a triple or more configuration may be used. In the gas supply pipe constituted by n pipes (n is an integer of 3 or more), the n pipes are arranged in order from the inside, the first gas supply pipe,..., the (n−1) th gas supply pipe. , When referred to as the nth gas supply pipe, the kth gas outlet provided in the kth gas supply pipe (k is an integer of 2 to n-1) and the (k + 1) th gas supply pipe The provided (k + 1) th gas outlet is arranged so that the projection projected perpendicularly to the inner wall surface of the (k + 1) th gas supply pipe in the outline of the kth gas outlet does not interfere with the (k + 1) th gas outlet. Is done. Specifically, it is desirable to set the diameter and thickness of the pipe to be added, the number and arrangement of the gas outlets provided on the side of the pipe, and the gas jetting direction in the same manner as the relationship between the inner pipe 27 and the outer pipe 28. . As the number of pipes constituting the gas supply pipe increases, the effect of preheating the atmospheric gas inside the gas supply pipe can be enhanced, but the diameter of the outermost pipe is inevitably thickened, There may be a disadvantage that the space for the arrangement increases and the manufacturing cost of the gas supply pipe also increases.

(Inner tube 27 and outer tube 28, gas outlet shape)
In the first embodiment, the inner tube 27 and the outer tube 28 are cylindrical, and the inner tube gas outlet 30 and the outer tube gas outlet 31 are circular. These shapes are not limited to them, and for example, the gas supply pipe may be a square shape, or the gas outlet may be a square shape. Moreover, although the gas jet port is an opening provided on the side surface of the gas supply pipe, the gas jet port is not limited to this, and may be, for example, an opening provided at the tip of a branch pipe branched from the gas supply pipe.

(Assembly of the gas supply pipe 19)
A gas supply pipe 19 having a double pipe structure having an inner pipe 27 and an outer pipe 28 is formed by inserting the inner pipe 27 into the outer pipe 28 and then fitting a bush 29 between the inner pipe 27 and the outer pipe 28. 27 can be assembled in the procedure of fixing. When the gas supply pipe 19 has three or more pipes, a pipe having an outer diameter smaller than the inner diameter is inserted into a pipe having a large inner diameter, and a bush 29 is provided in a gap between the two pipes. Repeat the installation and assemble. For example, when the gas supply pipe 19 is constituted by the first to third gas supply pipes, the second gas supply pipe is inserted into the third gas supply pipe, the bush 29 is attached, and then the second gas supply pipe is connected. The bush 29 is attached by inserting the first gas supply pipe inside. During this assembly, the relative positions and the relative angles of the inner tube gas outlet 30 and the outer tube gas outlet 31 are adjusted so that the positional relationship described above is achieved. The gas supply pipe 19 may be assembled by a procedure in which the outer pipe 28 is first arranged in the heat treatment apparatus 10, the inner pipe 27 is inserted, and the bush 29 is attached.

(About mixing atmospheric gas components)
In the first embodiment, an example in which one kind of gas component is used as the atmospheric gas is shown. When the atmospheric gas is composed of two or more kinds of gas components, a gas flow rate adjustment unit is provided for each atmospheric gas supply source that supplies each gas component, and the atmospheric gas component mixing ratio can be controlled together with the atmospheric gas flow rate. It is good also as a structure.

FIG. 5 is a diagram showing an outline of one configuration example that can control the gas component mixing ratio, and shows a configuration that can control the mixing ratio of two types of gas components. This configuration example includes a gas supply pipe 19, gas supply sources 24a and 24b, and gas flow rate adjusting units 25a and 25b.
When controlling the mixing ratio of two or more kinds of gas components, for example, as shown in FIG. 5, gas supply sources 24a and 24b for individually storing gas A and gas B as atmosphere gases are provided, and those gases are provided. The gas flow rate adjusting units 25a and 25b may be provided for each of the supply sources 24a and 24b, and the branched gas supply pipe 19 may be connected to the gas supply sources 24a and 24b via the gas flow rate adjusting units 25a and 25b. The gas flow rate adjusting units 25a and 25b function as an adjusting unit for the flow rate of the atmospheric gas supplied to the gas supply pipe 19, and also function as a gas component mixing ratio adjusting unit that adjusts the mixing ratio of the gas components. For example, a regulator or a flow meter can be used as the gas flow rate adjusting units 25a and 25b. For example, a gas cylinder or a gas generator can be used as the gas supply sources 24a and 24b. Of course, atmospheric gas is not limited to what consists of two types of gas, You may consist of three or more types of gas.

(Regarding the gas exhaust mechanism of the heat treatment apparatus 10)
Next, the gas exhaust mechanism of the heat treatment apparatus 10 will be described. The heat treatment of the object to be processed 11 proceeds by supplying heat from the upper heater 17 and the lower heater 18 shown in FIG. 1A and contacting the object 11 with the atmospheric gas ejected from the gas outlet 20. To do. During the heat treatment, evaporative gas may be generated from the object 11 due to evaporation or chemical reaction of components contained in the object 11. If this evaporative gas stays inside the furnace body 13, a reaction opposite to a desired chemical reaction may occur in the object 11 to be processed. Therefore, this evaporated gas needs to be discharged out of the furnace together with the atmospheric gas.

  The gas exhaust mechanism of the heat treatment apparatus 10 is a mechanism for discharging the gas sucked into the gas suction port 22 installed inside the furnace body 13 to the outside of the furnace body 13 as shown in FIG. . Here, the gas exhaust mechanism includes a gas exhaust pipe 21 provided with a gas suction port 22 shown in FIG. 1B and a gas exhaust pipe 21 shown in FIG. An exhaust flow rate adjusting unit 26 (exhaust fan and its control unit) for adjusting the flow rate is included.

(About gas exhaust pipe 21 and gas exhaust method)
A cylindrical gas exhaust pipe 21 which is a part of a gas exhaust mechanism for exhausting evaporated gas from the inside of the furnace body 13 to the outside penetrates the furnace body 13 from the lateral direction (left and right direction in FIG. 1A). . As shown in FIG. 2, the gas exhaust pipe 21 is connected to an exhaust flow rate adjusting unit 26 that is a part of the gas exhaust mechanism outside the furnace body 13. Further, as shown in FIG. 1B, the position of the gas exhaust pipe 21 inside the furnace body 13 is above the transport path (transport roller 14) of the stacking member 12. In order to avoid the above-described interference with the upper heater 17, the gas exhaust pipe 21 is preferably installed in parallel with the upper heater 17 like the gas supply pipe 19.

  Similar to the side surface of the gas supply pipe 19, a plurality of gas suction ports 22 are provided on the side surface inside the furnace body 13 of the gas exhaust pipe 21. Therefore, as shown in FIG. 1B, the evaporated gas generated from the object 11 by the heat treatment is sucked from the gas suction port 22 together with the surrounding atmospheric gas, and is discharged to the outside of the furnace body 13 through the gas exhaust pipe 21. Is done.

(About the shape, arrangement, and number of the gas exhaust pipe 21 and the gas suction port 22)
Of course, the configuration of the gas exhaust mechanism is not limited to this, and the shape, arrangement, and number of the gas exhaust pipe 21 and the gas suction port 22 depend on the type of heat treatment to be performed on the workpiece 11 and It selects suitably according to the shape of the processed material 11 and the stacking member 12, arrangement | positioning, and the number.

(Material of gas exhaust pipe 21)
As the material of the gas exhaust pipe 21, here, an alumina ceramic having heat resistance and corrosion resistance to the object 11, the atmospheric gas, and the evaporation gas is used. The material of the gas exhaust pipe 21 is appropriately selected according to the type of the object 11 to be processed, the atmospheric gas, and the evaporation gas, satisfies the heat resistance at the operating temperature, and has the corrosion resistance to the object 11 to be processed, the atmospheric gas, and the evaporation gas. As long as it has, materials other than alumina ceramics can also be used.

(Regarding the zone division and configuration of the heat treatment apparatus 10)
In the furnace body 13 of the heat treatment apparatus 10, as described above, the internal space is divided into a plurality of zones (treatment spaces) corresponding to the heat treatment process along the transport direction Dc. The gas supply mechanism, gas exhaust mechanism, upper heater 17 and lower heater 18 described above are provided in a part or all of a plurality of zones according to the heat treatment process. For example, the zone where the evaporated gas is not generated may be configured not to have a gas exhaust mechanism. Further, the zone in which the workpiece 11 is rapidly cooled may be configured not to include the upper heater 17 and the lower heater 18.

  As described above, the upper heater 17 and the lower heater 18, the gas supply mechanism, and the gas exhaust mechanism are provided in each zone according to the type of heat treatment. As a result, it is possible to optimally control the output of the upper heater 17 and the lower heater 18 in accordance with the heat supply performed in each zone such as temperature rise, soaking, and cooling of the workpiece 11. It is possible to perform optimum control of the flow rate of the atmospheric gas and control of the component mixing ratio of the atmospheric gas in accordance with the heat treatment performed in each zone such as synthesis accompanied by reaction and particle growth.

(About conveyance detection and output control)
In addition, it is preferable to provide the conveyance sensor 14b shown, for example in FIG. 2 as a detection means which detects that the to-be-processed object 11 is conveyed. The conveyance sensor 14b includes an upper heater temperature controller 17a for controlling the output of the upper heater 17 and the lower heater 18 in each zone when the workpiece 11 is not conveyed (that is, the rotation of the conveyance roller 14). A signal is sent to the heater temperature controller 18a. When these controllers receive the signal, they reduce the output of their respective heaters. The signal from the transport sensor 14b is also sent to the gas flow rate adjusting unit 25, and the flow rate of the atmospheric gas supplied to the gas supply pipe 19 in each zone is controlled according to the transport status (for example, transport is performed). It is preferred that the gas flow rate be reduced when not in use. By controlling the heater or the like according to the conveyance status, it is possible to reduce the energy consumption of the heat treatment apparatus 10 when production is not performed, and to further reduce the running cost of the heat treatment apparatus 10.

(Embodiment 2)
FIG. 6 shows a schematic cross-sectional view of a surface perpendicular to the transport direction and perpendicular to the transport surface of the heat treatment apparatus 10 according to Embodiment 2 of the present invention. In FIG. 6, the same elements as those described in the first embodiment are denoted by the same reference numerals, and description of these elements may be omitted below.

(About the overall configuration of the device)
The heat treatment apparatus 100 according to the second embodiment of the present invention includes an object to be processed 11, a stacking member 12, a furnace body 13, a transfer roller 14, an upper heater 17, a lower heater 18, a gas supply pipe 19, A heat treatment part 110 having an internal space surrounded by the gas outlet 20, the gas exhaust pipe 21 (not shown), the gas inlet 22 (not shown), and the furnace body 13 is arranged in the height direction (vertical direction). And a combined gas supply pipe 33 to which the gas supply pipes 19 of the respective stages are connected outside the furnace bodies 13. In the second embodiment, all of the stacked heat treatment sections 110 are disposed in the space inside the furnace body 13 from the gas supply pipe 19 including the inner pipe 27 and the outer pipe 28, as in the heat treatment apparatus 10 of the first embodiment. The atmosphere gas is ejected. In another form, the one or more heat treatment sections may comprise a conventional gas supply pipe.

(About device operation)
This heat treatment apparatus 100 has a structure in which a plurality of furnace bodies 13 that define the heat treatment apparatus 10 described in the first embodiment as the heat treatment section 110 are stacked in the height direction (vertical direction). FIG. 6 shows a multi-stage furnace body 32 in which three furnace bodies 13 are laminated. Inside the furnace body 13 at each stage, the stacking member 12 on which the workpieces 11 are loaded is transported simultaneously. Therefore, the productivity of the heat treatment apparatus 100 is improved by a factor of three compared to the one-stage configuration.

(About gas supply method)
The gas supply pipe 19 provided in each stage of the heat treatment section 110 is connected to the merged gas supply pipe 33 which is a part of the gas supply mechanism outside the furnace body 13. The combined gas supply pipe 33 is connected to the gas supply source 24 outside the furnace body 13 so as to have a configuration similar to the configuration shown in FIG. Each stage of the gas supply pipe 19 includes the inner pipe 27, the outer pipe 28, and the bush 29 shown in FIGS. 3A and 3B, as in the first embodiment. The arrangement and the number of the gas outlets 30 and 31 provided in the inner pipe 27 and the outer pipe 28, the direction of the gas jetting, and the like can be performed with sufficient preheating of the atmospheric gas at all stages by the method described in the first embodiment. The selection is made so that the supply of an equal amount of gas to the object to be processed 11 is compatible.

(Regarding the merits of multi-layer lamination of heat treatment part 110)
According to the above configuration, the introduction of the atmospheric gas from the outside to the inside of the furnace body 13 is performed from the side wall facing the furnace body 13 in the lateral direction. Therefore, in the apparatus of the second embodiment, there is no need to provide a gas introduction path on the upper surface and the lower surface of each stage of the furnace body 13 as shown in Patent Document 1, and as shown in Patent Document 1. In addition, since it is not necessary to provide an extra space for gas preheating in the upper space in the furnace, the height of the heat treatment section 110 (that is, the furnace body 13 that defines the heat treatment section 110) is suppressed while suppressing the installation height of the apparatus. Multi-stage stacking is possible.

  The advantages of downsizing the furnace body 13 are as described in the first embodiment. Furthermore, since the upper surface of the lower furnace body 13 and the lower surface of the upper furnace body 13 are shared by the multistage lamination of the furnace body 13 in the height direction, compared to the case where the furnace body 13 is not laminated in multiple stages, The heat dissipation area to the outside of the furnace of the apparatus of the second embodiment is reduced. This provides the advantage that energy costs can be significantly reduced.

(Regarding the number of stages in which the heat treatment part 110 is laminated)
The number of stages for stacking the heat treatment units 110 is not limited to three. The heat treatment section may be stacked in any number of layers as long as the installation height of the heat treatment apparatus 100 and the load capacity of the floor allow. As the number of stages increases, productivity improves and the energy cost per unit production can also be reduced. On the other hand, as the number of stages increases, the difficulty of conveyance and the difficulty of uniform gas supply and heat supply to each stage also increase.

(About heater output control)
It is desirable to provide a temperature controller (output control unit) for individually controlling the output of the upper heater 17 and the lower heater 18 provided in the heat treatment unit 110 of each stage. By doing so, the outputs of the upper heater 17 and the lower heater 18 are optimally controlled to avoid the influence of heat radiation from the upper surface and the lower surface of the multistage furnace body 32 to the outside, and the loading members in each stage. 12 and the temperature unevenness of the workpiece 11 can be suppressed.

(Regarding the effect of the second embodiment)
According to the second embodiment, even in the heat treatment apparatus 100 in which the heat treatment units 110 are stacked in multiple stages in the height direction, the atmosphere gas is preheated without requiring extra space and an additional heat source, and the workpiece 11 is processed. It is possible to make the temperature of the gas uniform when coming into contact with the substrate and to suppress uneven heat treatment. As a result, productivity can be significantly improved and energy costs can be significantly reduced.

  According to the heat treatment apparatus of the present invention, without requiring an extra space or an additional heat source, it is possible to preheat the atmospheric gas and uniformize the temperature of the gas when contacting the object to be processed. Unevenness can be suppressed. Therefore, the heat treatment apparatus of the present invention is useful for the manufacture of products in various fields that require a heat treatment that involves the supply of atmospheric gas to an object to be processed conveyed inside the furnace body during the manufacturing process.

DESCRIPTION OF SYMBOLS 1, 11 To-be-processed object 2, 12 Stacking member 3, 13 Furnace body 4, 14 Conveyance roller 10 Heat processing apparatus 17 Upper heater 18 Lower heater 19 Gas supply pipe 20 Gas outlet 21 Gas exhaust pipe 22 Gas inlet 27 Inner pipe 28 Outer pipe 29 Bush 30 Inner pipe gas outlet 31 Outer pipe gas outlet 100 Heat treatment apparatus 110 Heat treatment section

Claims (8)

A heat treatment apparatus for performing a heat treatment involving supply of atmospheric gas to an object to be treated in a space surrounded by walls constituting the furnace body (hereinafter also referred to as “furnace interior”),
A heater for controlling the temperature distribution inside the furnace body;
A first gas supply pipe provided with a first gas jet port for jetting atmospheric gas along the first gas jet direction;
A second gas supply pipe provided outside the first gas supply pipe with a second gas jet port for jetting atmospheric gas along the second gas jet direction;
The projection when the outline of the first gas outlet is vertically projected on the inner wall surface of the second gas supply pipe does not interfere with the second gas outlet,
Atmospheric gas is introduced from the outside of the furnace body into the first gas supply pipe, and is ejected into the second gas supply pipe through the first gas outlet provided in the first gas supply pipe. Then, it is ejected from a second gas ejection port provided in the second supply pipe, and is supplied to an object to be processed inside the furnace body.
Heat treatment equipment. The coordinates in the longitudinal direction of the first gas supply pipe at the center of the gas outlet provided in the first gas supply pipe are:
2. The heat treatment apparatus according to claim 1, wherein the center of the gas outlet provided in the second gas supply pipe is different from the coordinates in the longitudinal direction of the second gas supply pipe.   The heat treatment apparatus according to claim 1 or 2, wherein the first gas ejection direction and the second gas ejection direction are different from each other. The said 1st gas supply pipe | tube and the said 2nd gas supply pipe | tube are each provided with the said some 1st gas ejection port and the said 2nd gas ejection port in any one of Claims 1-3. Heat treatment equipment. Of the plurality of second gas outlets provided in the second gas supply pipe, the region between the two second gas outlets located closest to both side walls of the furnace body is defined as the second gas supply pipe. 5. The plurality of first gas outlets provided in the first gas supply pipe when being equally divided into three in the longitudinal direction are arranged at least one in each of the three equally divided regions. Heat treatment equipment. The heat treatment apparatus according to any one of claims 1 to 5, wherein the material of the first gas supply pipe and the second gas supply pipe has a surface emissivity of 0.5 or more. One or more gas supply pipes are provided outside the second gas supply pipe, and the first to nth gas supply pipes (n is an integer of 3 or more),
An outline of a kth gas outlet provided in a kth gas supply pipe (k is an integer not smaller than 2 and not larger than n-1) is perpendicular to an inner wall surface of the (k + 1) th gas supply pipe. The projection when projected does not interfere with the second gas outlet,
Atmospheric gas is introduced from the outside of the furnace body into the first gas supply pipe, and sequentially passes from the first gas outlet through the (n−1) outlet, and sequentially from the second gas supply pipe to the nth. Ejected into the gas supply pipe, and then ejected from the nth gas ejection port provided in the nth supply pipe, and supplied to the object to be processed inside the furnace body,
The heat processing apparatus in any one of Claims 1-6.   A multi-stage heat treatment apparatus in which a plurality of heat treatment parts are stacked, and at least one heat treatment part is the heat treatment apparatus according to claim 1.

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