Infrared heating apparatus

Abstract

To provide an infrared heating apparatus capable of executing in a short time heating processing such as binder removing processing and burning processing.SOLUTION: An infrared heating apparatus comprises: a placement section 34 on which an object C is placed; a heater lamp 31 that radiates infrared rays to heat the object C; a furnace chamber 21 in which the placement section 34 and the heater lamp 31 are disposed and which is configured closable in an airtight manner; a gas supplying section that supplies gas into the furnace chamber 21; and a gas exhaust section that discharges gas from the furnace chamber. The apparatus further comprises: a steam supplying section 60 that supplies steam into the furnace chamber other than the gas supplied from the gas supplying section; and pressure control means 3b that controls pressure in the furnace chamber to be positive pressure or negative pressure.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an infrared heating device, and more particularly to an infrared heating device including a mounting section for mounting an object thereon, a heater lamp for irradiating infrared light to heat the object, a furnace chamber in which the mounting section and the heater lamp are arranged and which is configured to be sealable, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber. [Background technology]

[0002] Conventionally, as an infrared heating device as described above, for example, the one described in Patent Document 1 is known. In this device, atmospheric gas is introduced into the furnace through the gap of the far-infrared heater in the ceiling of the furnace. As the binder removal process (hereinafter simply referred to as "binder removal") progresses, C (carbon) contained in the binder component increases in the furnace, and if it is not discharged (exhausted) outside the furnace, the heater and the like will be contaminated by the C (carbon) component, and the heating efficiency will decrease. However, this device does not have an exhaust structure, so it cannot solve the problem of contamination. In addition, since this device continuously transports and heats the object, the inside of the furnace cannot be made airtight, making it difficult to control and manage the atmosphere. Therefore, it took time to remove the binder and heat (sinter). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-114092 A Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the above-mentioned conventional circumstances, an object of the present invention is to provide an infrared heating device capable of performing heating treatments such as binder removal treatment and firing treatment in a short period of time. [Means for solving the problem]

[0005] In order to achieve the above-mentioned object, the infrared heating device of the present invention is characterized in that it is configured to include a mounting section for mounting an object, a heater lamp for irradiating infrared light to heat the object, a furnace chamber in which the mounting section and the heater lamp are arranged and which is configured to be sealable, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber, and further includes a steam supply section for supplying steam into the furnace chamber separately from the gas supplied from the gas supply section, and a pressure control means for controlling the pressure in the furnace chamber to positive or negative pressure.

[0006] Here, the infrared heating device according to the present invention heats the object placed on the mounting section with infrared light from the heater lamps in a furnace chamber that is configured to be sealable and can rapidly heat (raise the temperature) the object. At this time, components such as binders and solvents present inside the object can be burned in a short time and are combined with the oxygen inside to rapidly release organic components (carbon). On the other hand, this sudden temperature rise may cause a lot of thermal stress on the target object, which may cause cracks, etc. According to the above configuration, a steam supply unit is further provided that supplies steam into the furnace chamber in addition to the gas supplied from the gas supply unit. This allows steam to be supplied from the steam supply unit into the furnace chamber during the heat treatment, which makes it easier for oxygen to penetrate into the target object, further promoting the heat treatment (reaction) and preventing the occurrence of cracks, etc. Moreover, the apparatus further includes a pressure control means for controlling the pressure in the furnace chamber to positive or negative pressure. When the pressure in the furnace chamber is made positive, pressure is applied to the inside of the furnace chamber when steam is introduced, so that the steam can be filled evenly in the furnace chamber and distributed evenly to the object, and the heat treatment (reaction) can be promoted. On the other hand, when the pressure in the furnace chamber is made negative, the exhaust of gas in the furnace chamber is promoted. In this way, by controlling the pressure in the furnace chamber together with the supply of steam, the treatment can be accelerated.

[0007] In the above configuration, it is preferable that the furnace further includes a cooling means for cooling the furnace wall of the furnace chamber, and the steam supply unit includes a heating unit for heating the steam before supplying it to the furnace chamber. In order to cool the entire heating furnace, the furnace wall is provided with a cooling means such as a chiller, and the furnace wall is cooled. By heating the steam with the heating unit before supplying it to the furnace chamber, it is possible to suppress a decrease in the temperature of the steam and prevent condensation from occurring in the furnace chamber.

[0008] In this configuration, the heating section may be provided on the ceiling of the furnace wall and may have a plurality of nozzles protruding into the furnace chamber. The nozzles may have a plurality of through holes on all four sides of the circumferential surface of a nozzle body, and the tip of the nozzle body may be closed. This allows the steam to be distributed evenly over the entire object placed on the placement section.

[0009] In the above configuration, the steam supply unit may supply the steam from the top of the furnace chamber, and the gas exhaust unit may exhaust the gas in the furnace chamber from at least one of the side surfaces of the furnace chamber. Since the steam is supplied from the top and the gas is exhausted from at least one of the side surfaces, the generated gas is less likely to be trapped in the furnace chamber, and the exhaust is performed smoothly. The placement unit is a rectangular tray having long sides parallel to the longitudinal direction of the heater lamps, and the gas exhaust unit exhausts the gas in the furnace chamber from both side surfaces of the furnace chamber that face the short sides of the tray. As a result, the generated gas flows to both side surfaces along the long side direction of the tray, suppressing the stagnation of the generated gas and enabling more efficient exhaust.

[0010] On the other hand, in the above configuration, the steam supply unit may supply the steam from an upper portion of the furnace chamber, and the gas exhaust unit may exhaust the gas within the furnace chamber from the upper portion of the furnace chamber.

[0011] In the above configuration, the pressure control means may control the pressure in the furnace chamber to a positive pressure while the steam is being supplied into the furnace chamber. By making the pressure in the furnace chamber positive, the pressure is applied to the inside of the furnace chamber when the steam is introduced, so that the steam can be uniformly filled in the furnace chamber and distributed uniformly to the object, and the heat treatment (reaction) can be promoted.

[0012] In addition, in the above configuration, the furnace chamber includes a step temperature setting unit that sets a heating step for increasing the furnace temperature in the furnace chamber and a temperature decreasing step for decreasing the furnace temperature multiple times, and an output adjustment unit that adjusts the output of the heater lamp based on the increase and decrease of the furnace temperature, and the step temperature setting unit sets the heating rate and the temperature decreasing rate in a process in which the heating step and the temperature decreasing step are alternately repeated at least two times, and the output adjustment unit adjusts the output of the heater lamp based on the heating rate and the temperature decreasing rate to irradiate the infrared light from the heater lamp. According to the experiments of the inventors, it was found that when the temperature is increased in a short time, the oxygen concentration in the furnace decreases during the heating. On the other hand, even if the temperature after the heating is kept for a certain period of time, almost no change in the oxygen concentration in the furnace is observed. That is, it is presumed that the de-binding is promoted during the heating. Then, by lowering the temperature after this rapid temperature increase and then rapidly increasing the temperature again, and repeating the heating and cooling at least two times, it is possible to perform a process such as de-binding in a short time.

[0013] In the above configuration, the steam supply unit may further include a storage tank for storing hot water, a mixed gas supply unit for supplying mixed gas into the hot water, and a heating pipe for heating and supplying the steam generated in the storage tank to the heating unit. In this case, the steam supply unit may further include an oven temperature measuring unit for measuring the oven temperature in the oven chamber, and a supply start temperature setting unit for setting a supply start temperature when the steam is supplied into the oven chamber, and the steam supply unit may supply the steam from the heating unit to the oven chamber when the oven temperature exceeds the supply start temperature. The steam supply unit may further include a heating temperature setting unit for setting the temperature of the storage tank, the temperature of the heating pipe, and the temperature of the heating unit. In this way, condensation can be prevented by controlling the supply of steam. In any of the above configurations, for example, the target object is an MLCC. Effect of the Invention

[0014] According to the above-mentioned features of the infrared heating device of the present invention, it is possible to carry out heating processes such as binder removal and firing in a short period of time.

[0015] Other objects, configurations and effects of the present invention will become apparent from the following detailed description of the preferred embodiments of the present invention. [Brief description of the drawings]

[0016] [Figure 1] 1 is a conceptual diagram of an infrared heating device according to the present invention. [Diagram 2] FIG. 2 is a conceptual diagram of a steam supply unit of the infrared heating device according to the present invention. [Diagram 3] FIG. 2 is a block diagram of a control device. [Figure 4] FIG. 2 is a perspective view showing a part of the furnace chamber broken away. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] 1A and 1B are diagrams showing each nozzle, in which (a) is a perspective view of the nozzle, and (b) is a cross-sectional view of the nozzle. [Figure 8]FIG. 4 is a schematic vertical cross-sectional view showing the relationship between each nozzle and a suction port. [Figure 9] FIG. 13 is a diagram showing an example of a processing step profile. [Figure 10] FIG. 10 is a diagram showing changes in furnace temperature in the profile shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] (Overall composition) Next, the present invention will be described in more detail with reference to the accompanying drawings as appropriate. As shown in Figs. 1 to 10, an infrared heating device 1 according to the present invention is roughly equipped with a gas supply system 2, a gas exhaust system 3, a steam supply system 6, a camera 7, a control device 8, and a heating furnace 20. A tray 34, which is a placement section on which an object C to be treated is placed, is a horizontally elongated square dish with edges, and has a rectangular shape with long sides parallel to a longitudinal direction L1 of a heater lamp 31 described later. In this embodiment, an example will be described below in which a large number of MLCCs (multi-layer ceramic capacitors), which are the object C, are placed on the tray 34 and treated continuously from degreasing (de-baking) to main firing.

[0018] (Gas supply system 2) The gas supply system 2 includes a supply path 2a1, an electromagnetic valve 2b1, and a gas cylinder 2c1, and supplies gas in the gas cylinder 2c1 to nozzles 30, which are gas supply ports (gas supply units) provided in a plurality of portions on the upper portion of the firing furnace 20. The gas supply system 2 also includes a supply path 2a2, an electromagnetic valve 2b2, and a gas cylinder 2c2, and supplies cooling gas in the gas cylinder 2c2 to cooling nozzles 50, which are provided in a plurality of portions directly below the tray 34. An example of the cooling gas is nitrogen N2 gas.

[0019] (Gas exhaust system 3) Meanwhile, the gas exhaust system 3 includes an exhaust path 3a and an ejector 3b, and in this embodiment, the gas in the furnace chamber 21 is forcibly exhausted from left and right gas exhaust ports (gas exhaust parts) 35, 35 provided on both sides of the furnace chamber 21 facing the short side of the tray 34. The ejector 3b functions as a pressure control means that is controlled by the control device 8 to control the pressure in the furnace chamber 21 to a positive or negative pressure. In addition to supplying and exhausting gas, the control device 8 also executes processes from degreasing to main firing in accordance with set conditions (profile, programming).

[0020] (Steam supply system 6) The steam supply system 6 has a steam supply unit 60 that supplies steam We into the furnace chamber 21 separately from the gas supplied from the gas supply nozzle 30. In this embodiment, the steam supply unit 60 supplies steam We from an upper portion (ceiling) 20a of the heating furnace 20.

[0021] As shown in FIG. 2, the steam supply unit 60 generally includes a heating unit 61 that heats the steam We before it is supplied to the furnace chamber 21, a storage tank 62 that stores hot water H for generating the steam We to be supplied to the heating unit 61, and a mixed gas tank 63 as a mixed gas supply unit that supplies mixed gas into the storage tank 62.

[0022] The heating section 61 has a box 61a provided on the ceiling 23a of the heating furnace 20 and a plurality of steam supply nozzles 61b penetrating the ceiling 23a from inside the box 61a and projecting into the furnace chamber 21. The box 61a is provided with a heater 61c for heating the internal space. As shown in Figs. 4 and 5, the furnace wall 23 of the furnace chamber 21 is provided with a cooling water passage 36 as a cooling means for cooling the heating furnace 20. Therefore, by heating and supplying the steam We by the heating section 61 immediately before supplying it to the furnace chamber 21, a decrease in the temperature of the steam We is suppressed and condensation is prevented in the furnace chamber 21. The heating section 61 is provided with a temperature sensor 61d for measuring the internal temperature.

[0023] The storage tank 62 is provided with a heater 62b in a tank body 62a, and heats the hot water H to a predetermined temperature. The mixed gas supplied from the mixed gas tank 63 is supplied into the hot water H through a supply pipe 62c, and steam (air bubbles) are generated in the tank body 62. The generated steam We is then supplied to the heater 61 through a discharge pipe 62d and a heating pipe 64. The heating pipe 64 is heated to, for example, 30°C to 50°C to prevent the temperature of the steam We from dropping. The heating pipe 64 is also provided with a temperature sensor 64a for measuring the internal temperature.

[0024] The mixed gas tank 63 includes a flow rate control unit 63a such as an MFC (mass flow controller) to control the amount of gas supplied to the tank body 62a. The mixed gas contains at least hydrogen and nitrogen, for example, and the mixture ratio thereof is appropriately adjusted.

[0025] (Heat Lamp 31) The heater lamps 31 heat the tray 34 with infrared rays. Meanwhile, the temperature measurement unit 32 measures the temperature of the tray 34 with a thermocouple. With the temperature measurement unit 32 monitoring the temperature, an output adjustment unit 88a of the control device 8, which will be described later, controls the heating power of the heater lamps 31, and heating or cooling is performed according to a profile set (programmed) in a profile setting unit 80, which will be described later.

[0026] (Control device 8) The control device 8 is configured, for example, by a personal computer, and as shown in FIG. 3, roughly includes a profile setting unit 80 that sets at least the binder removal conditions and firing conditions for the MLCC as the target C, a monitoring unit 87, a control unit 88, and a recording unit 89.

[0027] 1 and 2 indicate an electrical control system, and all of the members, measuring units, sensors, etc. connected to these send signals or data to the control device 8, which controls them from a control unit 88. The camera 7 sequentially records the conditions inside the heating furnace 20 in a recording unit 89 of the control device 8. That is, the control device 8 can easily set and change the temperature profile, i.e., when and at what temperature to heat or cool during processing (from degreasing to main firing), and the timing of both gas supply and exhaust, and can perform heating or cooling while recording images from the camera 7 together with the temperature data of the execution result.

[0028] The profile setting unit 80 generally includes a step temperature setting unit 81, a temperature setting unit 82, a gas amount setting unit 83 that adjusts the amount of gas supplied to the furnace chamber 21 and the amount of gas exhausted from the furnace chamber 21, and a steam supply setting unit 84 that sets the supply of steam We.

[0029] The step temperature setting unit 81 sets a heating step S1 for increasing the furnace temperature in the furnace chamber 21 and a temperature decreasing step S2 for decreasing the furnace temperature in the furnace chamber 21 multiple times. The step temperature setting unit 81 sets the heating rate and the temperature decreasing rate in the de-binding process and the firing process, which at least include a process step in which the heating step S1 and the temperature decreasing step S2 are alternately repeated at least two times. In this specification, the process step in which the heating step S1 and the temperature decreasing step S2 are alternately repeated at least two times is referred to as a pulse process S. The heating rate set is +5°C / sec to +25°C / sec, and the temperature decreasing rate is -25°C / sec to -5°C / sec.

[0030] The temperature setting unit 82 includes a supply start temperature setting unit 82a that sets the supply start temperature when steam We is supplied into the furnace chamber 21, and a heating temperature setting unit 82b that sets the temperature of the storage tank 62, the temperature of the heating pipe 64, and the temperature of the heating unit 61. In addition, the step temperature setting unit 81 sets the peak temperature and the keep temperature in each step during processing.

[0031] The gas amount setting unit 83 has a supply amount setting unit 83a which sets the amount of gas supplied into the furnace chamber 21, and an exhaust amount setting unit 83b which sets the amount of gas exhausted from the furnace chamber 21. The steam supply setting unit 84 sets the supply of steam We to be on or off during heat treatment such as the binder removal process or the firing process.

[0032] The control unit 88 includes an output adjustment unit 88a that adjusts the output of the heater lamp 31 based on the temperature increase rate and the temperature decrease rate set by the step temperature setting unit 81. The output adjustment unit 88a adjusts the output of the heater lamp 31 based on the temperature increase rate and the temperature decrease rate set by the step temperature setting unit 81, and causes the heater lamp 31 to irradiate infrared light.

[0033] The monitoring unit 87 monitors conditions inside the furnace, such as the temperature (furnace temperature) of the temperature measuring unit 32, the heating temperatures of the temperature sensors 61d, 64a, and the oxygen concentration of the oxygen concentration sensor 39 inside the furnace. The control unit 88 controls the supply and exhaust of gas, the supply and stop of steam We, the output of the heater lamp, and the like, based on the conditions (profile) set by the profile setting unit 80 and various data monitored by the monitoring unit 87. The recording unit 89 records the various data monitored by the monitoring unit 87, the control of the control unit 88, and the processing conditions of the camera 7, etc.

[0034] (heating furnace 20) As shown in Figures 2 to 4, the heating furnace 20 has an inner surface in which parabolas with six vertices gather like a flower in cross section, and the furnace wall 23 has the same shape in the longitudinal direction L1 from left to right. At the focal points F (F1, F2a, F2b, F3a, F3b) of each parabola, rod-shaped heater lamps are arranged along the longitudinal direction L1 so that their central filaments are positioned. Therefore, infrared light emitted from the filaments of the heater lamps 31 at the focal points F is reflected by the reflective surface of the furnace wall 23, travels in parallel, and gathers in the center of the internal space 22 of the furnace chamber 21, heating this part evenly.

[0035] This point will be described in particular with reference to FIG. 5. In the figure, heater lamps 31 are provided at four locations on the left and right and one location below. Among the light paths of the light generated from the foci F (F1, F2a, F2b, F3a, F3b) of each parabola where the filament is located, those passing near the ends and the center of the parabola are depicted by two-dot chain lines. The tray 34 is contained within the four diamond-shaped areas in the center by the light from the left and right foci F2a, F2b, F3a, F3b, and it can be seen that it is heated evenly. In addition, the center including the contact member 32a is heated by the lower focus F1, and the temperature can be measured accurately. In addition to the direct irradiation from each focus F to the tray 34, the light that enters the surface of the parabola in the area of ​​the other foci is reflected by that surface and is also irradiated to the tray 34.

[0036] Therefore, even if the tray 34 has a width in the front-rear direction L2 perpendicular to the longitudinal direction L1, it can be heated evenly. The cross-sectional shape may be an ellipse other than a parabola, with the filament of the heater lamp 31 located at one focus and the center of the tray 34 at the other focus. However, the parabolic shape is superior in terms of uniformity of heating over the entire tray 34. In the case of an ellipse, uneven heating can be alleviated by increasing the light-emitting area of ​​the filament.

[0037] Although not shown, the heater lamp 31 has a spiral filament, which is the heat generating part (light emitting part), housed in a straight quartz tube along the longitudinal direction L1 and supported on the left and right, with halogen gas or the like sealed inside. Power is supplied from the left and right terminals, and the heat generation state is controlled by the control device 8 mentioned above via a thyristor or the like. When the filament emits light due to the supply of power, the infrared light emitted from it is reflected by the furnace wall 23 mentioned above, and heating is performed as described above. Five heater lamps 31 are provided excluding the top one.

[0038] 4 and 5, the furnace chamber 21 is appropriately formed with a cooling water passage 36 as a means for cooling the furnace wall 23, and overheating of the furnace chamber 21 is prevented by circulating cooling water through the cooling water passage 36. Since the furnace wall 23 is cooled by this cooling water passage 36, when steam We is supplied into the furnace chamber 21, condensation may occur on the inner surface of the furnace wall 23, causing water droplets to adhere to the inner surface. Therefore, in the present invention, as described above, the steam We is heated by the heating section 61, thereby suppressing a drop in the temperature of the steam We and preventing condensation from occurring in the furnace chamber 21. Moreover, the occurrence of condensation is further suppressed by controlling the control device 8 to supply steam We into the furnace chamber 21 when the temperature inside the furnace is heated to a predetermined temperature or higher.

[0039] The furnace chamber 21 of the heating furnace 20 has a front opening 24 and a rear opening 25 arranged side by side in the front-rear direction L2, making it easy to clean the internal space 22. Each opening is closed in a sealed state by a front cover 26 and a rear cover 27. A through hole 28a is formed in the center of the furnace chamber 21, and an observation window 28 made of a transparent heat-resistant material such as quartz is provided therein, and images are taken by the camera 7. Although only one heater lamp 31 is shown in FIG. 8 as a representative, the terminals at both ends penetrate and protrude outside the furnace chamber 21, and the internal space 22 is kept airtight by seals 31a and fixing caps 31b at each end.

[0040] The rear cover 27 is mainly used only during cleaning, and the tray 34 is normally inserted and removed by opening and closing the front cover 26. The rear cover 27 is supported by a hinge on the lower side and is opened and closed with the hinge as a fulcrum. On the other hand, the front cover 26 is opened and closed by being moved horizontally by an operating device (not shown).

[0041] The tray 34 has a flat top surface, a flange around the periphery to prevent the MLCCs from spilling out, and is formed with a substantially uniform cross section that is long horizontally along the longitudinal direction L1. The temperature measuring unit 32 has a support arm 32b inserted into a hole formed in a small block-shaped contact member 32a that contacts the tray 34, in which a thermocouple junction 32c is disposed, and is connected to the control device 8 by a cable via a connector 32d. The tray 34 and the contact member 32a are both made of the same material that absorbs infrared light, and examples of such materials that can be used include ceramics, silicon carbide (SiC), and silicon carbide (SiC) coated with zirconia (ZrO2).

[0042] In addition, directly below the tray 34, a plurality of cooling nozzles 50 for blowing cooling gas toward the bottom surface of the tray 34 are arranged at appropriate intervals along the longitudinal direction L1. In the cooling nozzle 50, a plurality of nozzle holes 50a are formed at appropriate intervals along the nozzle longitudinal direction (front-rear direction L2) on the upper surface of the nozzle 50. This allows the entire tray 34 to be cooled uniformly and quickly. As described above, the tray 34 is heated by infrared light from the heater lamp 31. The infrared heating device 1 according to the present invention does not directly heat or cool the object C itself, but heats or cools it through the tray 34, so that rapid and uniform heating and cooling can be performed, and variations in each object C can be suppressed, particularly when baking a large number of fine objects C such as MLCCs. Moreover, since the temperature measuring unit 32 is in contact with the bottom surface of the tray 34, temperature control can be performed appropriately.

[0043] A pair of support arms 33 made of a heat-resistant material such as quartz is provided on the front cover 26. By using a material that does not easily absorb infrared light (a material with high infrared light transmittance), heat transfer to the front cover 26 is prevented and irradiation of the tray 34 with infrared light is not impeded, improving temperature control and response. The support arm 32b is disposed between the support arms 33, 33, and the contact member 32a is disposed between them.

[0044] A plurality of through holes 29 are formed in the upper surface of the furnace chamber 21, and a plurality of nozzles 30 and steam supply nozzles 61b, which are gas supply ports, are attached in an airtight state. These nozzles 30 and 61b are made of a material that does not easily absorb infrared light (a material with high infrared light transmittance), such as a quartz tube, so that irradiation of the infrared light onto the tray 34 is not hindered. A plurality of nozzle holes 30b are formed around the periphery of the tubular nozzle body 30a, so that the gas is dispersed in all directions.

[0045] The nozzles 30, 61b described above allow the gas and steam We to be distributed evenly over the flat tray 34. Moreover, the gas and steam We are exhausted by the ejector 3b from gas exhaust ports 35, 35 provided on the left and right sides of the tray 34 along the longitudinal direction L1 at approximately the same height as the tray 34. This combination of supply and exhaust of the gas and steam We allows the layer of gas and steam We to be evenly distributed over the target C on the tray 34. In the case of MLCCs, in order to prevent the solvent from escaping due to by-product removal or the like, or the oxidation of the paste, these adverse effects can be prevented by constantly flowing and renewing the layer of gas and steam We while keeping it even.

[0046] In the commonly used tunnel furnaces shown in the above documents, the objects to be treated with de-bye and sintering are transported in sequence by a transport device such as a belt, and therefore the pressure inside the furnace cannot be controlled to be switched between positive and negative pressures. For example, in the case of negative pressure, the gas (air) inside the furnace is drawn to exhaust the gas generated inside the furnace, but the gas heated by the burner or heater is also exhausted, which tends to lower the temperature inside the furnace, making it difficult to exhaust the gas strongly. In addition, in the case of positive pressure, various gases generated from the objects are not exhausted and are trapped inside the furnace, making it difficult to perform stable treatment such as sintering and de-bye.

[0047] On the other hand, the heating furnace 20 according to the present invention heats (heats) the tray 34 with infrared light from the heater lamp 31, so the temperature inside the furnace does not drop suddenly due to exhaust. In addition, since the temperature measuring unit 32 is provided on the tray 34, the temperature of the object can be measured accurately. As described above, exhaust from the gas exhaust ports 35, 35 is performed by the ejector 3b. Therefore, by controlling the supply amount of gas supplied into the furnace chamber 21 and the exhaust amount exhausted from the furnace chamber 21, it is possible to control the pressure inside the furnace chamber 21 during processing while avoiding a drop in the temperature inside the furnace. By increasing the gas exhaust amount by the ejector 3b relative to the gas supply amount into the furnace chamber 21, the furnace chamber 21 is made negative pressure, and by decreasing the gas exhaust amount by the ejector 3b, the furnace chamber 21 is made positive pressure, thereby controlling the switching between positive and negative pressures in the furnace chamber 21.

[0048] By creating a negative pressure inside the furnace chamber 21, various gases generated from the target object C can be forcibly exhausted to the outside of the furnace chamber 21 without lowering the temperature inside the furnace, and the gas generated does not become trapped inside the furnace chamber 21, minimizing adverse effects on the target object C. In addition, the adhesion of the generated gas to the surfaces of the heater lamps 31 and the inner surface of the furnace wall 23 can be suppressed, preventing a decrease in thermal efficiency.

[0049] On the other hand, if the pressure inside the furnace chamber 21 is made positive, pressure is applied inside the furnace chamber 21 when the steam We is introduced, so that the introduced steam We can be filled evenly inside the furnace chamber 21 and distributed evenly to the target object C. On the other hand, if the pressure inside the furnace chamber 21 is made negative, exhaust of gas inside the furnace chamber 21 is promoted and retention of the generated gas can be suppressed.

[0050] Next, as a method of using the infrared heating device 1, a process for debinding (debinding, degreasing) an MLCC having copper paste containing glass frit attached to the electrodes as the object C, and subsequently performing a firing process in the same furnace chamber after the binder removal process will be described using the profiles shown in Figs. 9 and 10 as examples.

[0051] First, the control device 8 sets a profile as shown in FIG. 9, for example. In this example, the process has 14 steps, and the peak temperature (°C), heating rate (°C / min), peak temperature maintenance time (sec), supply gas (nitrogen-hydrogen mixed gas and nitrogen gas) and steam on / off (dry / wet), and exhaust rate (L / min) in each step are set. This profile shows the relationship between temperature (vertical axis) and time (horizontal axis) as shown in FIG. 10. In this case, the supply start temperature setting unit 81a sets the supply start temperature when supplying steam We into the furnace chamber 21 to, for example, 100°C. As a result, for example, in step 2, steam We is supplied into the furnace chamber 21 when the furnace temperature exceeds 100°C.

[0052] Then, the objects C are laid out on the tray 34 and transferred by placing them on the support arms 33, 33 using a robot arm or the like. Next, an opening / closing actuator (not shown) is extended to close the front cover 26 in an airtight state, and the tray 34 is set in the center of the furnace chamber 21.

[0053] Next, the control unit 88 turns on the heater lamp 31 to start heating, opens the solenoid valve 2b1 to supply nitrogen gas to the nozzle 30, and operates the ejector 3b to exhaust the gas inside the furnace chamber 21 from the gas exhaust port 35. Then, according to the set profile, the output adjustment unit 88a adjusts the output of the heater lamp 31 based on the set temperature increase rate and temperature decrease rate to irradiate infrared light from the heater lamp 31. The control unit 88 also controls the gas supply, exhaust, and steam on / off based on the gas amount setting unit 83 and the steam supply setting unit 84. Note that steam We is supplied into the furnace chamber 21 when the temperature inside the furnace exceeds 100°C.

[0054] 9 and 10, step 3 is set by the step temperature setting unit 81 to a temperature increase step S1 with a temperature increase rate of 5° C. / min, and step 4 is set to a temperature decrease step S2 with a temperature increase rate of -5° C. / min (temperature decrease rate of 5° C. / min). Steps 5 to 10 are set by the step temperature setting unit 81 to alternately repeat the temperature increase step S1 and the temperature decrease step S2. Therefore, in steps 3 to 10, the temperature increase step S1 and the temperature decrease step S2 are alternately repeated four times, and this heat treatment process becomes a pulse heat treatment S.

[0055] Furthermore, in this example, the supply amount setting unit 83a and the exhaust amount setting unit 83b set the gas exhaust amount into the furnace chamber 21 to be less than the gas supply amount in the temperature increase step S1 (steps 3, 5, 7, 9), and set the gas exhaust amount into the furnace chamber 21 to be greater than the gas supply amount in the temperature decrease step S2 (steps 4, 6, 8, 10). That is, the pressure inside the furnace chamber 21 is controlled to be positive in the temperature increase step S1, and the pressure inside the furnace chamber 21 is controlled to be negative in the temperature decrease step S2.

[0056] As described above, this profile is set to repeat heating (heating rate is positive) and cooling (heating rate is negative) multiple times. In addition to MLCCs, electronic components such as inductors, coils, and high-frequency boards are manufactured by mixing binders (resins, organic substances) into the materials, and it is necessary to remove the binders contained in the materials when commercializing them. In the commonly used tunnel furnaces shown in the above literature, the combustion efficiency is low, so after heating to a specified temperature, the temperature is kept for a long period of time (several hours to several tens of hours) to remove binders (degreasing).

[0057] In addition, in conventional tunnel furnaces, the air (gas) inside is heated by a burner or heater to perform heat treatment, so it is difficult to suddenly change the temperature of the air, and the air is discharged together with the generated gas, which tends to lower the temperature inside the furnace, making it difficult to perform strong exhaust.In addition, in the case of positive pressure, various gases generated from the target material are not discharged and are trapped inside the furnace, making it difficult to perform stable treatment such as calcination and de-bining.

[0058] However, in the infrared heating device 1 according to the present invention, the tray 34 is heated (heated) by infrared light from the heater lamp 31 in the airtight furnace chamber 21, so that the temperature of the object C can be rapidly increased (heated). As a result, the binder, solvent, etc. present inside the object C can be burned in a short time, and the organic components (carbon) are quickly released by combining with the oxygen inside. According to the experiments of the inventors, it was found that when the temperature is raised in a short time, the oxygen concentration in the furnace decreases during the temperature rise. On the other hand, even if the temperature after the temperature rise is kept for a certain period of time, almost no change in the oxygen concentration in the furnace is observed. In other words, it is presumed that the de-binding is promoted during the temperature rise. Then, after this rapid temperature rise, the temperature is lowered and then rapidly raised again, and the temperature rise and fall are repeated several times, so that the de-binding can be performed in a short time.

[0059] As described above, a sudden temperature rise may cause a large amount of thermal stress to be applied to the target object C, which may result in cracks or the like. Therefore, in this example, the steam supply setting unit 84 sets the supply of steam We to ON during the binder removal process (steps 2 to 11). As a result, steam We is supplied from the steam supply unit 60 to the furnace chamber 21 during the binder removal process, which makes it easier for oxygen to penetrate into the target object C, further promoting the binder removal and preventing the occurrence of cracks or the like. In this example, the pressure in the furnace chamber 21 is controlled to a positive pressure during the temperature increase step S1, and the pressure in the furnace chamber 21 is controlled to a negative pressure during the temperature decrease step S2.

[0060] In particular, when the target object C is a large product, it takes time for the steam to penetrate into the target object C (product). Therefore, by making the pressure in the furnace chamber 21 positive when the temperature is increased, which promotes the debinding (reaction), the penetration of oxygen into the target object C is promoted, and by making the pressure in the furnace chamber 21 negative when the temperature is decreased, exhaust is promoted, so that the debinding process can be speeded up. Even in the case of a product with a small amount of binder component in the target object C, by making the pressure in the furnace chamber 21 positive when the temperature is increased, the debinding process can be promoted.

[0061] In this example, step 11 corresponds to the secondary binder removal process. When the temperature exceeds 900°C, if the target C does not contain a binder, gas due to binder removal is not generated, so the exhaust amount is made smaller than the supply gas amount, and the inside of the furnace chamber 21 is controlled to a positive pressure.

[0062] In the profile of this example, the baking process (step 12) is set following the baking process (steps 2 to 11). As described above, the control device 8 of the present invention can set the conditions (profiles) for the baking process and the baking process in succession, so that it is not necessary to separate the baking process and the baking process in different processes and devices as in the past, and the process from the baking process to the baking process can be performed in succession in the same furnace. In addition, since the pressure in the furnace chamber 21 can be controlled to positive / negative pressure, the baking process can be promoted by switching between positive / negative pressure during the baking process, and the exhaust of gas generated in the baking process can also be promoted. Therefore, even if the baking process and the baking process are performed in succession in the same furnace, the quality of the object C is not deteriorated.

[0063] When the baking is completed, in steps 13 and 14, the power supply to the heater lamps 31 is reduced or stopped to lower the temperature. Furthermore, if necessary, nitrogen gas as a cooling gas may be sprayed from the cooling nozzle 50 onto the tray 34 to promote cooling of the object C and the tray 34. In these cooling processes (steps 13 and 14) after the baking process, the supply of steam We is set to off by the steam supply setting unit 84, and the supply of steam We is completed by the baking process. The respective operating devices are operated in the reverse order of the set-up, the tray is replaced, and the baking operation is completed. With the infrared heating device 1 according to the present invention, the baking process and the baking process can be completed in an extremely short time, as shown in FIG. 10.

[0064] Next, other possible embodiments of the present invention will be listed, in which like elements are given the same reference numerals. In the above embodiment, the cooling nozzle 50 is disposed directly below the tray 34, but the position of the cooling nozzle 50 is not limited to directly below the tray 34. For example, the cooling nozzle 50 may be disposed diagonally below the tray 34. By disposing the cooling nozzle 50 below the tray 34 in this manner, the tray 34 can be cooled efficiently without affecting the object C. Note that the cooling nozzle 50 can also be disposed near the tray 34 as long as it is in a form that does not affect the object C.

[0065] Although the copper paste is used in the MLCC in the above embodiment, it is also possible to use a silver paste. In this case, oxygen may be used as the gas other than nitrogen. In the above embodiment, the object C is an MLCC coated with copper paste containing glass frit as an external electrode. However, the object C and the firing process thereof are not limited to the above embodiment. The infrared heating device 1 according to the present invention can also be used, for example, in a chip firing process which is a process preceding the external electrode firing process of the MLCC.

[0066] In the above embodiment, the gas supplied to the inside of the heating furnace 20 and the cooling gas are described separately, but two types of gas may be used by switching between them. Of course, the number of types is not limited to two, and one or more types of gas may be used.

[0067] The configuration of the infrared sintering device 1 can be modified in other ways without departing from the spirit of the invention. For example, the cross-sectional shape of the furnace wall is formed of six parabolas, but it can also be formed of five or four parabolas.

[0068] In the above embodiment, steam is supplied from the top of the furnace chamber 21 and gas is exhausted from both side surfaces of the furnace chamber 21 that face each other across the tray, but this is not limited to both sides, and gas within the furnace chamber 21 may be exhausted from at least one of the side surfaces of the furnace chamber 21. On the other hand, when the amount of gas to be exhausted is large, steam may be supplied from the top of the furnace chamber 21 and gas within the furnace chamber 21 may be exhausted from the top of the furnace chamber 21.

[0069] 9 and 10 are merely examples, and are not limited thereto. In the above example of the profile, during the baking process, the pressure in the furnace chamber 21 is controlled to a positive pressure during the temperature increase step S1, and the pressure in the furnace chamber 21 is controlled to a negative pressure during the temperature decrease step. However, throughout the baking process, steam We may be supplied into the furnace chamber 21 and the pressure in the furnace chamber 21 may be controlled to a positive pressure. This promotes the penetration of oxygen into the object C, and speeds up the baking process. In addition, during the baking process, the pressure in the furnace chamber 21 may be controlled to a negative pressure to promote exhaust. Note that, as in the above embodiment, the pressure in the furnace chamber 21 may be controlled to a negative pressure after the baking process.

[0070] The embodiment of the present invention is configured as described above, but more comprehensively, it may have the following configurations. Another invention having the configuration shown below aims to provide a binder removal apparatus that can significantly shorten the binder removal processing time and a binder removal method using the same.

[0071] In order to achieve the above object, the binder removal apparatus is characterized in that it comprises a mounting section for mounting an object containing a binder component, a heater lamp for irradiating infrared light to heat the object, a furnace chamber in which the mounting section and the heater lamp are arranged and which is configured to be sealable, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber, and has a step temperature setting section which sets a plurality of heating steps for increasing the furnace temperature in the furnace chamber and a temperature decreasing step for decreasing the furnace temperature, and an output adjustment section which adjusts the output of the heater lamp based on the increase and decrease of the furnace temperature, wherein the step temperature setting section sets each of the heating rate and the temperature decreasing rate in the binder removal process which includes at least a process step (binder removal process, pulse process) in which the heating step and the temperature decreasing step are alternately repeated at least two times, and the output adjustment section adjusts the output of the heater lamp based on the heating rate and the temperature decreasing rate to cause the heater lamp to irradiate the infrared light.

[0072] Here, the debinding apparatus according to the present invention comprises a placement section for placing an object containing a binder component, a heater lamp for irradiating infrared light to heat the object, a furnace chamber in which the placement section and the heater lamp are arranged and which is configured to be sealable, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber. Thus, the object containing the binder component is heated by infrared light from the heater lamp in the furnace chamber which is configured to be sealable and in which the heater lamp is arranged, so that the object can be heated (heated) rapidly. At this time, components such as the binder and solvent present inside the object can be burned in a short time, and are combined with the oxygen inside to rapidly release organic components (carbon). According to the experiments of the inventors, it was found that when the temperature was raised in a short time, the oxygen concentration in the furnace decreased during the temperature rise. On the other hand, even if the temperature after the temperature rise was kept for a certain period of time, almost no change was observed in the oxygen concentration in the furnace. In other words, it is presumed that the removal of by-products is promoted during the temperature rise. According to the above configuration, the apparatus includes a step temperature setting unit that sets a heating step for increasing the temperature in the furnace chamber and a temperature decreasing step for decreasing the temperature in the furnace chamber multiple times, and an output adjustment unit that adjusts the output of the heater lamp based on the increase and decrease of the temperature in the furnace. The step temperature setting unit sets the heating rate and the temperature decreasing rate in the de-oxidation process that includes at least a process step (pulse process) in which the heating step and the temperature decreasing step are alternately repeated at least two times, and the output adjustment unit adjusts the output of the heater lamp based on the heating rate and the temperature decreasing rate to irradiate the infrared light from the heater lamp. In this way, by decreasing the temperature after a rapid temperature increase and then increasing the temperature again rapidly, and repeating the heating and decreasing at least two times, the de-oxidation time can be significantly shortened, and the de-oxidation process can be performed in a short time.

[0073] In the above configuration, the apparatus further includes a steam supply unit which supplies steam into the furnace chamber separately from the gas, and a pressure control means which controls the pressure in the furnace chamber to a positive pressure or a negative pressure, the steam supply unit supplies the steam into the furnace chamber during the de-baking process, and the pressure control means controls the pressure in the furnace chamber to a positive pressure during the temperature increase step and to a negative pressure during the temperature decrease step. For example, when it takes time for the steam to penetrate into the inside of the object, the pressure can be controlled to a positive pressure during the temperature increase step in which de-baking is promoted, thereby promoting the penetration of oxygen into the inside of the object, and the pressure can be controlled to a negative pressure during the temperature decrease step to promote exhaust, thereby further speeding up the de-baking process.

[0074] In addition, the above configuration may further include a steam supply unit that supplies steam into the furnace chamber separately from the gas, and a pressure control means that controls the pressure in the furnace chamber to a positive pressure or a negative pressure, and the steam supply unit supplies the steam into the furnace chamber during the by-product treatment, and the pressure control means controls the pressure in the furnace chamber to a positive pressure during the by-product treatment. If the pressure in the furnace chamber is made positive, pressure is applied to the inside of the furnace chamber when the steam is introduced, so that the steam can be filled evenly in the furnace chamber and distributed evenly over the object, further facilitating the by-product treatment. In any of the above configurations, the temperature increase rate and the temperature decrease rate may be, for example, 5°C / sec to 25°C / sec.

[0075] In any of the above configurations, it is preferable to further include a cooling means for cooling an outer wall of the furnace chamber, and the steam supply unit has a heating unit for heating the furnace wall of the furnace chamber before supplying the steam into the furnace chamber. In order to cool the entire heating furnace, a cooling means such as a chiller is provided on the furnace wall, and the furnace wall is cooled. By heating the steam with the heating unit before supplying it into the furnace chamber, it is possible to prevent condensation from occurring in the furnace chamber, suppress a drop in the temperature of the steam, and prevent condensation from occurring in the furnace chamber.

[0076] In the above configuration, the furnace chamber may be provided with an oxygen meter for measuring an oxygen concentration in the furnace chamber. Also, in the above configuration, for example, the object is an MLCC having a Ni internal electrode formed thereon, and is to be subjected to a firing process continuously after the by-product removal process.

[0077] The above-mentioned configuration further includes a steam supply unit for supplying steam into the furnace chamber separately from the gas, and a pressure control means for controlling the pressure in the furnace chamber to a positive pressure or a negative pressure, and a firing process is performed in the same furnace chamber after the by-product removal process, and the steam supply unit supplies the steam into the furnace chamber during the by-product removal process, and the pressure control means controls the pressure in the furnace chamber to a positive pressure during the by-product removal process and to a negative pressure during the firing process. By making the pressure in the furnace chamber positive during the by-product removal process, pressure is applied to the inside of the furnace chamber when steam is introduced, so that the steam can be filled evenly in the furnace chamber and can be distributed evenly to the object, thereby facilitating the by-product removal process. By making the pressure in the furnace chamber negative during the firing process, the gas generated by firing can be quickly exhausted to the outside of the furnace chamber, thereby suppressing adverse effects on the product and shortening the firing time.

[0078] In addition, in order to achieve the above object, a feature of a method for removing binders using a de-binding apparatus is that, in the method for removing binders using a de-binding apparatus, the de-binding apparatus comprises a mounting section for mounting an object containing a binder component, a heater lamp for irradiating infrared light to heat the object, a furnace chamber in which the mounting section and the heater lamp are arranged and configured to be sealable, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber, and has a step temperature setting section for setting a heating step for increasing the furnace temperature in the furnace chamber and a temperature decreasing step for decreasing the furnace temperature multiple times, and an output adjustment section for adjusting the output of the heater lamp based on the increase and decrease in the furnace temperature, and is configured to set respective heating and decreasing rates in a de-binding process including at least a heat treatment process in which the heating step and the temperature decreasing step are alternately repeated at least two times, and adjust the output of the heater lamp based on the heating rate and the temperature decreasing rate to irradiate the infrared light from the heater lamp.

[0079] In the above configuration, the desorption apparatus further includes a steam supply unit which supplies steam into the furnace chamber separately from the gas, and a pressure control means which controls the pressure in the furnace chamber to a positive pressure or a negative pressure, and the steam supply unit supplies the steam into the furnace chamber during the desorption process, and the pressure control means controls the pressure in the furnace chamber to a positive pressure during the desorption process.

[0080] In the above configuration, the de-burning apparatus further includes a steam supply unit which supplies steam into the furnace chamber separately from the gas, and a pressure control means which controls the pressure in the furnace chamber to a positive pressure or a negative pressure, and the steam supply unit supplies the steam into the furnace chamber during the de-burning process, and the pressure control means controls the pressure in the furnace chamber to a positive pressure during the temperature increase step and to a negative pressure during the temperature decrease step.

[0081] In addition to the above-described embodiments, the present invention may more comprehensively include the following configurations: The present invention has an object to provide an MLCC manufacturing apparatus capable of performing the de-binding process and the firing process continuously in the same furnace, and an MLCC manufacturing method using an infrared heating device.

[0082] In order to achieve the above object, the MLCC manufacturing apparatus is characterized in that it comprises a mounting section for mounting MLCCs, a heater lamp for irradiating infrared light to heat the MLCCs, a furnace chamber in which the mounting section and the heater lamps are arranged and which is configured to be sealable, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber, and further comprises a profile setting section for setting at least debinding conditions and firing conditions for the MLCCs, and a power adjustment section for adjusting the output of the heater lamp based on an increase and decrease in the furnace temperature in the furnace chamber, and the profile setting section includes at least a step temperature setting section for setting a plurality of heating steps for increasing the furnace temperature in the furnace chamber and a temperature decreasing step for decreasing the furnace temperature, and by irradiating the infrared light based on the output adjustment of the power adjustment section, a debinding process is performed by removing binder components from the MLCCs and exhausting gas containing the removed binder components, and then a firing process is performed in which the MLCCs from which the binder components have been removed are fired in the same furnace chamber.

[0083] Here, the MLCC manufacturing apparatus according to the present invention includes a mounting section for mounting MLCCs, a heater lamp for irradiating infrared light to heat the MLCCs, a furnace chamber in which the mounting section and the heater lamps are arranged and which is configured to be able to be sealed, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber. Therefore, since the MLCCs are heated by infrared light from the heater lamps in the furnace chamber which is configured to be able to be sealed and in which the heater lamps are arranged, the target object can be rapidly heated (temperature increased). According to the above configuration, the apparatus further includes a profile setting unit that sets at least the binder removal conditions and the firing conditions for the MLCC, and a power adjustment unit that adjusts the output of the heater lamp based on the rise and fall of the furnace temperature in the furnace chamber, and the profile setting unit includes at least a step temperature setting unit that sets a heating step for raising the furnace temperature in the furnace chamber and a temperature drop step for lowering the furnace temperature multiple times. Therefore, by irradiating the infrared light based on the setting of this step temperature setting unit and the output adjustment of the power adjustment unit, it is possible to remove the binder component from the MLCC and exhaust the gas containing the removed binder component to perform a binder removal process, and then perform a firing process in which the MLCC from which the binder component has been removed is fired in the same furnace chamber.

[0084] In the above configuration, the apparatus further includes a steam supply unit for supplying steam into the furnace chamber separately from the gas, and a pressure control means for controlling the pressure in the furnace chamber to a positive pressure or a negative pressure, the profile setting unit further includes a steam supply setting unit for setting the supply of the steam, and a gas amount adjustment unit for adjusting the amount of gas supplied to the furnace chamber and the amount of gas exhausted from the furnace chamber, the steam supply setting unit sets the supply of the steam to ON during the debaking process and sets the supply of the steam to OFF during the baking process, and the gas amount adjustment unit controls the pressure in the furnace chamber to a positive pressure by making the gas supply amount greater than the amount of gas exhausted during the debaking process, and controls the pressure in the furnace chamber to a negative pressure by making the gas supply amount less than the amount of gas exhausted during the baking process. By making the pressure in the furnace chamber positive during the debaking process, pressure is applied to the inside of the furnace chamber when steam is introduced, so that the steam can be filled evenly in the furnace chamber and distributed evenly over the object, thereby facilitating the debaking process. Furthermore, by creating a negative pressure in the furnace chamber during the firing process, gases generated during firing can be quickly exhausted to the outside of the furnace chamber, thereby suppressing adverse effects on the product.

[0085] In such a configuration, the step setting unit sets a process (pulse process) in which the heating step and the temperature decreasing step are alternately repeated at least twice in the by-product removal process and sets the heating rate and the temperature decreasing rate for each, and the output adjustment unit adjusts the output of the heater lamp based on the heating rate and the temperature decreasing rate to irradiate the infrared light from the heater lamp. By repeating the heating and decreasing processes at least twice by decreasing the temperature after a rapid temperature increase and then rapidly increasing the temperature again, the by-product removal time can be significantly shortened, and the by-product removal process can be performed in a short time.

[0086] In any of the above configurations, it is preferable that the apparatus further includes a cooling means for cooling an outer wall of the furnace chamber, and the steam supplying unit includes a heating unit for heating the furnace wall of the furnace chamber before supplying the steam into the furnace chamber. In order to cool the entire furnace, the furnace wall is provided with a cooling means such as a chiller, and the furnace wall is cooled. By heating the steam with the heating unit before supplying it into the furnace chamber, it is possible to prevent condensation from occurring in the furnace chamber, suppress a temperature drop in the furnace chamber, and prevent condensation from occurring in the furnace chamber.

[0087] In addition, in order to achieve the above object, a manufacturing method of MLCCs is characterized in that, in the manufacturing method of MLCCs using an infrared heating device including a mounting section for mounting MLCCs, a heater lamp for irradiating infrared light to heat the MLCCs, a furnace chamber in which the mounting section and the heater lamp are arranged and configured to be sealable, a gas supply section for supplying gas into the furnace chamber, and a gas exhaust section for exhausting gas from the furnace chamber, the infrared heating device further includes a profile setting section for setting at least debinding conditions and firing conditions for the MLCCs, the profile setting section including at least a step setting section for setting a heating step for increasing the furnace temperature in the furnace chamber and a temperature decreasing step for decreasing the furnace temperature multiple times, and an output adjustment section for adjusting the output of the heater lamp based on the increase and decrease in the furnace temperature, and by irradiating the infrared light based on the output adjustment of the output adjustment section, a binder component is removed from the MLCCs and a gas containing the removed binder component is exhausted to perform a debinding process, and then a firing process is performed in which the MLCCs from which the binder component has been removed are fired in the same furnace chamber. [Industrial Applicability]

[0088] The infrared heating device of the present invention can be used for heat treatment of MLCCs and other electronic components, as well as members other than electronic components that require control of temperature or gas atmosphere. [Explanation of symbols]

[0089] 1: infrared heating device (de-bye device, MLCC manufacturing device), 2: gas supply system, 2a1, 2a2: supply path, 2b1, 2b2: solenoid valve, 2c1, 2c2: gas cylinder, 3: gas exhaust system, 3a: exhaust path, 3b: ejector (pressure control means), 4a: current supply path, 6: steam supply system, 7: camera, 8: control device, 20: heating furnace, 21: furnace chamber, 22: internal space, 23: furnace wall, 23a: ceiling (upper part), 24: front opening, 25: rear opening part, 26: front cover, 27: rear cover, 28: observation window, 29: through hole, 30: gas supply nozzle (gas supply port, gas supply part), 30a: nozzle body, 30b: nozzle hole, 31: heater lamp, 31a: seal, 31b: fixing cap, 32: temperature measurement part, 32a: contact member, 32b: support arm, 32c: thermocouple junction part, 32d: connector, 33: support arm, 34: tray (mounting part, susceptor, setter), 35: gas exhaust port ( gas exhaust section), 36: cooling water channel (cooling means), 39: oxygen concentration measuring device (sensor), 50: cooling nozzle, 50a: nozzle hole, 60: steam supply section, 61: heating section, 61a: box, 61b: steam supply nozzle, 61b1: nozzle body, 61b2: nozzle hole, 61c: heater, 61d: temperature sensor, 62: storage tank, 62a: tank body, 62b: heater, 62c: supply pipe, 62d: exhaust pipe, 63: mixed gas tank (mixed gas supply unit), 63a: flow control unit (MFC), 64: heating pipe, 64a: temperature sensor, 80: profile setting unit, 81: step temperature setting unit, 82: temperature setting unit, 82a: supply start temperature setting unit, 82b: heating temperature setting unit, 83: gas amount setting unit, 83a: supply amount setting unit, 83b: exhaust amount setting unit, 84: steam supply setting unit, 87: monitoring unit, 88: control unit, 88a: output adjustment unit, 89: recording unit, L1: longitudinal direction, L2: front-rear direction, C: object (MLCC), H: hot water, We: steam

Claims

1. A placement unit on which an object is placed; A heater lamp that irradiates infrared light to heat the object; a furnace chamber in which the mounting portion and the heater lamps are arranged and which is configured to be sealable; a gas supply unit for supplying gas into the furnace chamber; a gas exhaust section that exhausts gas from within the furnace chamber; An infrared heating device comprising: a steam supply unit for supplying steam into the furnace chamber separately from the gas supplied from the gas supply unit; The infrared heating device further comprises a pressure control means for controlling the pressure in the furnace chamber to a positive pressure or a negative pressure.

2. 2. The infrared heating device according to claim 1, further comprising a cooling means for cooling a furnace wall of the furnace chamber, and the steam supply unit has a heating unit for heating the steam before it is supplied into the furnace chamber.

3. 3. The infrared heating device according to claim 2, wherein the heating section is provided on a ceiling of the furnace wall and has a plurality of nozzles projecting into the furnace chamber.

4. 4. The infrared heating device according to claim 3, wherein each of the nozzles has a plurality of through holes formed on all four sides of a circumferential surface of a nozzle body, and a tip of the nozzle body is closed.

5. 4. The infrared heating device according to claim 3, wherein the steam supply unit supplies the steam from an upper portion of the furnace chamber, and the gas exhaust unit exhausts the gas in the furnace chamber from at least one of the side surfaces of the furnace chamber.

6. 6. The infrared heating device according to claim 5, wherein the mounting portion is a rectangular tray having long sides parallel to the longitudinal direction of the heater lamps, and the gas exhaust portion exhausts gas from within the furnace chamber from both side surfaces of the furnace chamber opposite the short sides of the tray.

7. 4. The infrared heating device according to claim 3, wherein the steam supply unit supplies the steam from an upper portion of the furnace chamber, and the gas exhaust unit exhausts the gas within the furnace chamber from the upper portion of the furnace chamber.

8. 4. The infrared heating device according to claim 3, wherein the pressure control means controls the pressure in the furnace chamber to a positive pressure while the steam is being supplied into the furnace chamber.

9. 4. The infrared heating device according to claim 3, further comprising: a step temperature setting unit that sets a heating step for increasing the furnace temperature in the furnace chamber and a heating step for decreasing the furnace temperature multiple times; and an output adjustment unit that adjusts the output of the heater lamp based on the increase and decrease of the furnace temperature, wherein the step temperature setting unit sets a heating rate and a heating decrease rate in a process of alternately repeating the heating step and the heating decrease step at least two times, and the output adjustment unit adjusts the output of the heater lamp based on the heating rate and the heating decrease rate to irradiate the infrared light from the heater lamp.

10. The infrared heating device according to claim 3, wherein the steam supply unit further comprises a storage tank for storing hot water, a mixed gas supply unit for supplying a mixed gas into the hot water, and a heating pipe for heating and supplying the steam generated in the storage tank to the heating unit.

11. 11. The infrared heating device of claim 10, further comprising an inner furnace temperature measuring unit for measuring an inner furnace temperature in the furnace chamber, and a supply start temperature setting unit for setting a supply start temperature when the steam is supplied into the furnace chamber, wherein the steam supply unit supplies the steam from the heating unit into the furnace chamber when the inner furnace temperature exceeds the supply start temperature.

12. The infrared heating device according to claim 11, further comprising a heating temperature setting unit which sets the temperature of the storage tank, the temperature of the heating pipe, and the temperature of the heating unit.

13. The infrared heating device according to any one of claims 1 to 12, wherein the object is an MLCC.

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