JP6064199B2 - Heat treatment equipment - Google Patents

Description

  The present invention relates to a heat treatment apparatus for performing a heat treatment on an object to be heated conveyed inside a furnace body.

  The heat treatment apparatus is an apparatus that performs heat treatment for a long time at a relatively high temperature for the purpose of synthesis involving chemical reaction, removal of impurities, improvement of crystal structure, or particle growth. Such a heat treatment apparatus is an apparatus that heats an object to be heated with radiant heat or hot air from heaters arranged on the upper and lower parts of the object to be heated, and has no temperature difference for each place of the object to be heated, and efficiently. There is a need to heat.

  However, the temperature distribution of the conventional heat treatment apparatus includes a certain temperature variation. The main cause of the temperature variation is the width direction of the furnace (hereinafter referred to as “furnace width direction unless otherwise specified”), which is orthogonal to the direction (longitudinal direction of the furnace) in which the object to be heated is conveyed in the furnace of the heat treatment apparatus. This is because the temperature at both ends of the second portion is relatively lower than the other portions. That is, the in-plane temperature variation of the object to be heated is increased by the influence of the temperature difference that occurs in the furnace width direction. The cause of this variation is that, generally, the temperature of the furnace wall constituting the furnace body is low, so the amount of heat dissipated on the furnace wall side is greater than the amount of heat dissipated in the center in the furnace width direction. Further, in the direction in which the object to be heated is conveyed, in-plane temperature variation of the object to be heated may occur due to the influence of heater control variation or radiation rate variation on the conveying surface due to furnace atmosphere fluctuation. Since these temperature differences immediately lead to variations in quality, the ability to heat efficiently is required to keep the temperature differences within a certain range. Therefore, in order to keep the temperature difference of the object to be heated within a certain range, means for providing a heat equalizing plate that equalizes the temperature of the object to be heated by secondary radiation is known. For example, the method of Patent Document 1 is cited. It is done.

  FIG. 13 is an explanatory diagram of Patent Document 1. FIG. The heat treatment furnace 20 of FIG. 13 includes furnace walls 21, 22, 24, 25, heaters 23 arranged on the upper and lower furnace walls 21, 22 facing each other, and furnace walls 24, 25 next to the heat treatment furnace 20. And a heat-treating silicon plate 26 as a reflecting plate that is installed and soaks the inside of the furnace 20. By providing the heat treatment silicon plate 26 on the furnace walls 24 and 25, the heat of the heater 23 is reflected into the furnace 20 by the heat treatment silicon plate 26, so that the furnace temperature is made uniform. According to the structure of FIG. 13, when the temperature of the inside of the heat treatment furnace 20 is raised to 800 [° C.], the temperature difference between the furnace center and the furnace periphery is 5 [° C.].

JP 2008-138986 A

  However, in the conventional heat treatment apparatus represented by Patent Document 1, there is a problem that temperature variation occurs depending on the arrangement position of the object to be heated, the temperature in the furnace changes depending on the surrounding environment or changes over time, and the heat capacity of the substrate increases. If they are different, there is a problem that even if the heater setting value or the processing time is the same, the temperature change state of the substrate is different and the temperature distribution of the substrate varies.

  Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a heat treatment apparatus capable of uniformly heat treating an object to be heated regardless of a change in furnace temperature due to environmental changes or the kind of the object to be heated. is there.

  In order to achieve the above object, an aspect of the present invention is configured as follows.

One aspect of the present invention is a furnace body for heat-treating an object to be heated in an internal space;
A heat source inside the furnace body;
In a heat treatment apparatus having a soaking plate unit that secondaryly radiates radiation from the heat source between the heated object and the heat source and soaks the heated object.
The soaking plate unit arranges soaking plates provided with a plurality of rectangular openings in the furnace width direction perpendicular to the conveying direction of the heated object, and the longitudinal direction of each opening is the above It is arranged along the conveying direction, and the short direction of each opening is arranged in the furnace width direction, and the heat equalizing plate is a heat source side heat equalizing plate close to the heat source and far from the heat source. The heat source side soaking plate and the to-be-heated object side soaking plate are in contact with each other in the furnace body vertical direction orthogonal to the transport direction and the furnace width direction. When the emissivity of the surface of the heater-side soaking plate is ε _h and the emissivity of the surface of the heated object-side soaking plate is ε _w , Δε = | ε _h -ε _w | 0.6 emissivity difference [Delta] [epsilon] ≧ represented by, and a epsilon _h ≧ 0.8, the soaking plate unit , To the furnace width direction perpendicular to the conveying direction, it is divided into a plurality of thirds or more,
Further, the heat treatment apparatus slides the heat source side heat equalizing plate and the heated object side heat equalizing plate relatively in the furnace width direction so that the opening of the heat source side heat equalizing plate and the heated object side Provided is a heat treatment apparatus including a drive unit that moves between a state in which a phase with an opening of a heat equalizing plate coincides with a state in which the phase shifts.

  According to the heat treatment apparatus according to the aspect of the present invention, the heat treatment can be performed uniformly regardless of the furnace wall radiated heat, the ambient environment of the furnace body, the fluctuation of the furnace temperature due to the aging of the furnace material, or the kind of the object to be heated.

The inside of the heat processing apparatus in 1st Embodiment of this invention, Comprising: Sectional drawing along a furnace width direction Sectional drawing inside the heat processing apparatus in 1st Embodiment of this invention, and along a conveyance direction (A) And (b) is the top view and sectional drawing for demonstrating the soaking plate unit in 1st Embodiment of this invention, respectively. The figure which shows the heat-transfer form of the heat equalizing plate unit in 1st Embodiment of this invention. The figure which shows the relationship between the radiation rate difference and temperature difference of the soaking plate unit in 1st Embodiment of this invention. The figure which shows the relationship between the radiation rate and temperature difference of the soaking plate unit in 1st Embodiment of this invention. The figure which shows the temperature distribution of the conventional soaking plate The figure which shows the relationship between the opening part of the heat equalizing plate unit in 1st Embodiment of this invention, and a temperature difference. The figure which shows the relationship between the aperture ratio of the heat equalizing plate unit in 1st Embodiment of this invention, and a temperature difference. The figure which shows the opening part operating condition of the heat equalizing plate unit in 1st Embodiment of this invention, and the state of an aperture ratio. The figure which shows the example of the opening part operation pattern (temperature fall part) of the heat equalizing plate unit in 1st Embodiment of this invention. The figure which shows the relationship between the opening part operating condition of the heat equalizing plate unit in 1st Embodiment of this invention, and a temperature difference. The top view which shows the inside of the heat processing apparatus in 2nd Embodiment of this invention. The figure which shows the heat processing equipment using the conventional soaking plate

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
First, the overall configuration of the heat treatment apparatus 1 according to the first embodiment of the present invention will be described. FIG. 1A is a cross-sectional view of the inside of the heat treatment apparatus 1 according to the first embodiment of the present invention, taken along the furnace width direction orthogonal to the conveying direction of the article 2 to be heated. FIG. 1B is a cross-sectional view of the inside of the heat treatment apparatus 1 according to the first embodiment of the present invention, taken along the transport direction, and is a cross-sectional view taken along the line BB in FIG. For example, it is a cross-sectional view cut in the vertical direction. In addition, the arrow in FIG. 1A shows the flow until the primary radiation is secondarily radiated to the article 2 to be heated via the soaking plate unit 3. The sign of FIG. 1B, D _b represents the conveyance direction of the object to be heated 2. FIGS. 2A and 2B are views for explaining the overall structure of the heat equalizing plate unit 3 in the first embodiment of the present invention, and the heat equalizing plate unit according to the first embodiment of the present invention. 3 is a diagram showing a plan view and a cross-sectional view of FIG.

  The heat treatment apparatus 1 according to the first embodiment of the present invention includes a plurality of transport rollers 5, a heated object 2, a transport roller support 9, and a plurality of heat rollers arranged between the transport rollers 5 and the upper divided heater 4. For example, three soaking plate units 3, a plurality of soaking plate support frames 7 that respectively support a plurality of soaking plate units 3, and a plurality of soaking plate support frames 7 in a lateral direction (for example, a horizontal direction) A plurality of cylinder drive parts 6a, 6b, 6c to be moved, and a furnace body 1a configured to cover the entire apparatus with a heat insulating material 8 are provided. A plurality of divided heaters 4, a plurality of heat equalizing plate units 3, a part of the plurality of heat equalizing plate support frames 7 and a part of the conveying roller 5 are surrounded by a heat insulating material 8 on the conveying roller support 9. A furnace body 1a is formed, and the object to be heated 2 is heat-treated in the internal space of the furnace body 1a. The divided heater 4 functions as an example of a heat source. The soaking plate support frame 7 functions as an example of a support member. As an example of the object to be heated 2, a substrate is exemplified. The cylinder driving units 6a, 6b, and 6c function as an example of a driving unit, and specifically include hydraulic cylinders 6a, 6b, and 6c.

  The heat treatment apparatus 1 is a furnace that performs heat treatment, such as a baking furnace, a drying furnace, a curing furnace, or a reflow furnace. In the heat treatment apparatus 1, multi-point temperature control is performed according to the heat capacity or size of the heating target, the radiant heat from the divided heater 4 is individually controlled, and the furnace body that is heat-insulated by the heat insulating material 8 is uniformly heated. ing.

  Here, in the heat treatment apparatus 1, in the furnace, in addition to the divided heater 4, a plurality of soaking plate units 3 are provided in the middle portion between the upper divided heater 4 and the lower heated object 2. It arrange | positions on the soaking plate support frame 7, respectively. The plurality of heat equalizing plate units 3 are arranged between the object to be heated 2 and the divided heater 4, so that the radiation from the divided heater 4 is secondarily emitted and the object to be heated 2 is equalized. It has a function.

  As clearly shown in FIG. 2, as an example, the soaking plate unit 3 is divided into a plurality of three or more parts. In this example, the soaking plate unit 3 is composed of a soaking plate unit 3 of one metal plate in the center and two soaking plates on both sides sandwiching the soaking plate unit 3 in the center. Heat plate unit 3 (one furnace plate side of the first furnace wall side (for example, the left furnace wall side in FIG. 1A) and one soaking plate unit 3 on the second furnace wall side (for example, the right furnace wall side in FIG. 1A) The sheet is divided into three soaking plate units 3). One divided soaking plate unit 3 is configured by arranging a plurality of soaking plates 3b having a plurality of rectangular openings 3a in each metal plate in the furnace width direction. Each of the soaking plates 3b includes a heater-side soaking plate 10 having a plurality of rectangular openings 10a and a heated object-side soaking plate 11 having a plurality of rectangular openings 11a. It is configured to be stacked in contact with each other in the vertical direction of the furnace body orthogonal to the width direction. As will be described later, the heated object side heat equalizing plate 11 is relatively movable with respect to the heater side heat equalizing plate 10.

Note that C1 and C2 in FIG. 2 indicate the division positions of the metal plate of the soaking plate unit 3. Here, the metal plate of the heat equalizing plate unit 3 is divided into three by two division positions C1 and C2. Further, arrows D _h and D _w in FIG. 2 indicate the arrangement position directions of the divided heater 4 and the object to be heated 2, respectively. L _s in Figure 2 shows the opening short side direction length along the furnace width direction, Ws represents a vertical opening the longitudinal direction of the length and the furnace width direction. L indicates the length of one soaking plate unit 3 in the furnace width direction. L ₀ indicates the length in the furnace width direction of the arrangement space of the heat equalizing plate unit 3 as a whole.

As shown in FIG. 2, the heat equalizing plate unit 3 according to the first embodiment of the present invention is in a state where two heat equalizing plates, that is, the heater-side heat equalizing plate 10 and the heated object-side heat equalizing plate 11 are in contact with each other. The two layers are stacked. At this time, the heater-side soaking plate 10 is made of a material having a high emissivity obtained by sufficiently oxidizing the surface of the heat-resistant steel. The to-be-heated object side soaking plate 11 is made of a material having a lower emissivity than the heater side soaking plate 10 such as ceramic or fine flex mold. As an example, the heat equalizing plate unit 3 according to the first embodiment of the present invention includes, as an example, the two heat equalizing plates 10 and 11 having the opening 3a in the region (area of W _s × L _s ) illustrated in FIG. A plurality of pieces are cut out at equal intervals in the furnace width direction. In addition, since the heat treatment apparatus 1 maintains a uniform temperature distribution in the furnace width direction of the article 2 to be heated, the divided heater 4 and the soaking plate unit 3 are each divided into a plurality of pieces in the furnace width direction. . As an example, the divided heater 4 in FIG. 1A and the heat equalizing plate unit 3 in FIG. 2 each show a state of being divided into three.

  Further, the plurality of soaking plate support frames 7 on which the plurality of soaking plate units 3 are mounted are provided with cylinder driving portions 6a, 6b, 6c individually at one end thereof, and the cylinder driving portions 6a, 6b. , 6c are independently driven individually, and the corresponding heat equalizing plate support frame 7 is individually slid, that is, moved forward and backward independently in the furnace width direction, so that the heater-side heat equalizing plate 10 and the object to be heated are moved. The side soaking plate 11 is moved relatively. As an example, all the heater-side soaking plates 10 are fixed to the furnace body side, the heated object-side soaking plates 11 are supported by the soaking plate support frames 7, respectively, and the heated soaking plates 7 are heated as the soaking plates support frame 7 moves. The object side soaking plate 11 is moved relative to the heater side soaking plate 10. In place of such a configuration, conversely, all the heated object side heat equalizing plates 11 are fixed to the furnace body side, and the heater side heat equalizing plates 10 are respectively supported by the heat equalizing plate supporting frames 7 to support the heat equalizing plates. The heater side soaking plate 10 may move with respect to the article to be heated side soaking plate 11 as the frame 7 moves. Further, two types of soaking plate support frames 7 are provided for the heater side soaking plate 10 and for the heated object side soaking plate 11, and a drive unit is provided for each of the two types of soaking plate support frames 7 to provide a heater. The side soaking plate 10 and the heated object side soaking plate 11 are driven simultaneously, and as a result, the heated object side soaking plate 11 and the heater side soaking plate 10 move relatively. May be.

  Therefore, in this way, the heat equalizing plate unit 3 is interposed between the divided heater 4 and the object to be heated 2, and further, the object to be heated side heat equalizing plate 11 of the heat equalizing plate unit 3 is replaced with the heater side heat equalizing plate 10. On the other hand, by sliding in the furnace width direction by the cylinder driving parts 6a, 6b, 6c, the radiant heat from the divided heater 4 is made uniform, and the temperature variation in the furnace width direction of the heated object 2 conveyed by the conveying roller 5 is made. Can be reduced. Here, as an example, when the sliding amount of the heated object-side heat equalizing plate 11 is the minimum, it means a state where the rectangular openings coincide with each other, and the heated object-side heat equalizing plate 11 slides. When the amount is maximum, it means a state where each rectangular opening is closed. Therefore, in this example, the sliding amount of the heated object-side heat equalizing plate 11 is not less than 0 and not more than the width dimension of each opening.

  The heat transfer mode and the soaking effect by the soaking plate unit 3 according to the first embodiment of the present invention are characterized by the radiation rate, the number of divisions, or the opening shape parameters of the soaking plate unit 3. . The parameters and effects of the soaking plate unit 3 will be described based on specific verification results.

1A and 1B, as an example, first, the internal dimensions of the furnace body 1a made of a heat insulating material 8, the vertical direction (e.g., vertical direction) of Z = 200 of [mm], along the conveying direction _{D b} Length Y = 400 [mm], and lateral width X along the furnace width direction X = 800 [mm].

  Next, as an example, nine heated objects 2 having a height (thickness) of 1 [mm] are juxtaposed in the furnace width direction of the heat treatment apparatus 1 (left and right direction in FIG. 1A), and the distance between the heated objects 2 is determined. Was set to 10 [mm]. However, each dimension is not limited to these, and is set to an appropriate size according to the processing amount of the object to be heated 2.

  In such a state, each divided heater 4 was set to 600 [° C.] and heated from room temperature, and when the furnace temperature became stable, the temperature variation of the object to be heated 2 was evaluated.

As a precondition, the temperature fluctuation that may occur due to the ambient environment or changes over time is set to ± 0.4 [%], and the temperature variation target of the object to be heated is the temperature difference in the furnace width direction with respect to the heating temperature of the object to be heated. 0.6 [%]. Incidentally, hereinafter, unless otherwise noted, in 300 [mm] away from the central portion of the heated object 2 and the furnace body 1a of the central portion of the furnace body 1a of the furnace width direction perpendicular to the conveying direction D _b fireside The temperature difference between the heated part 2 and the heated object 2 is abbreviated as “600 mm wide heated object temperature difference” and is expressed by a value ΔT / T ₀ [%] obtained by dividing the temperature of the heated object 2 by the furnace average temperature T _0. .

FIG. 3 is a diagram for explaining the heat transfer mode of the heat equalizing plate unit 3. As shown in the upper side of FIG. 3, from the alignment state Sa in which the opening 10a of the heater-side heat equalizing plate 10 and the opening 11a of the heated object-side heat equalizing plate 11 are overlapped with each other, FIG. As shown on the lower side, the position shifts to the misalignment state Sb in which the opening 11a of the heated object-side heat equalizing plate 11 is slid and moved relative to the opening 10a of the heater-side heat equalizing plate 10 by L _s / 2. Assume that

  First, in the alignment state Sa, a part of the radiant heat RH1 of the radiant heat supplied from each of the divided heaters 4 is absorbed by each heater-side heat equalizing plate 10. The radiant heat RH2 that passes through the opening 10a of each heater-side soaking plate 10 passes through the opening 11a of the low-radiation-rate soaking plate 11 as it is, and heats the article 2 to be heated directly.

  On the other hand, in the misalignment state Sb, a part of the radiant heat RH3 of the radiant heat supplied from each of the divided heaters 4 is absorbed by the heater-side heat equalizing plate 10 as in the alignment state Sa. However, the radiant heat that has passed through the opening 10a of the heater-side heat equalizing plate 10 is absorbed by the heated object-side heat equalizing plate 11 because part of the radiant heat RH4 is shielded by the heated object-side heat equalizing plate 11. The radiant heat RH5 that has passed through the opening 10a of the heater-side soaking plate 10 excluding the radiant heat RH4 and that has passed through the opening 11a of the low emissivity soaking plate 11 directly heats the article 2 to be heated. .

  Therefore, by shifting from the alignment state Sa to the misalignment state Sb, when the radiation rate of the object-side heat equalizing plate 11 is larger than that of the heater-side heat equalizing plate 10, the radiant heat is emitted from each divided heater 4. The low emissivity area for receiving heat increases, and the high emissivity area for secondary radiation toward the object to be heated 2 and the transport roller 5 increases. That is, in the heat equalizing plate unit 3, the radiant heat from each of the divided heaters 4 is reduced and the secondary radiant heat radiated toward the object to be heated 2 is increased, so that the temperature is shifted from the alignment state Sa to the misalignment state Sb. Is lower.

  On the other hand, when the emissivity of the object to be heated-side heat equalizing plate 11 is smaller than that of the heater-side heat equalizing plate 10, the high emissivity area that receives radiant heat from each of the divided heaters 4 increases, and the object to be heated 2 In addition, the low emissivity area for secondary radiation toward the conveying roller 5 and the like increases. That is, in the heat equalizing plate unit 3, since the radiant heat from each of the divided heaters 4 increases and the secondary radiant heat radiated toward the object to be heated 2 decreases, the temperature is in a misaligned state as compared with the alignment state Sa. Sb is higher.

The heat transfer of these radiations can be summarized by the following equation.

Q = Q _in −Q _out −Q _trans

However,
Q: The amount of heat [J] stored in the heat equalizing plate unit 3;
Q _in : Radiant heat [J] supplied from the divided heater 4
Q _out : Radiant heat [J] secondarily radiated from the soaking plate unit 3 to the furnace material excluding the soaking plate unit 3
Q _trans : Dissipated heat [J] from the surface of the soaking plate unit 3 exposed to the furnace atmosphere to the furnace atmosphere.

  From the above, it is necessary for temperature control to increase the difference between the radiation rate of the heater-side heat plate 10 and the radiation rate of the heated object-side heat plate 11 that the heat-uniforming plate unit 3 constitutes. I understand.

FIG. 4 is a diagram showing the relationship between the emissivity difference and the temperature difference of the soaking plate unit 3. Specifically, the radiation rate difference between the heater-side soaking plate 10 and the heated object-side soaking plate 11 under the condition that the soaking plate unit 3 does not operate (slide) (corresponding to when the black circle slit in FIG. 4 is opened). The difference in emissivity in the relationship between Δε and the 600 mm width heated object temperature difference ΔT / T ₀ [%] and the conditions for operating the soaking plate unit 3 (corresponding to the opening and closing of the white circle in FIG. 4). FIG. 4 shows verification data that summarizes Δε and the 600 mm width minimum heated object temperature difference ΔT / T ₀ [%]. At this time, the emissivity of the heater-side soaking plate 10 is ε _h, and the emissivity of the heated object-side soaking plate 11 is ε _w , respectively, and a range of 0 <ε _h <1 and 0 <ε _w <1. Defined by the range of Further, the difference between the emissivities ε _h and ε _w (radiation rate difference), that is, | ε _h −ε _w | is defined as Δε. However, under the condition that the soaking plate unit 3 is not operated, the opening 10a of the heater-side soaking plate 10 and the opening 11a of the heated-side soaking plate 11 as shown in the alignment state Sa in FIG. It is set as the alignment state superimposed so that it might correspond. As a result of this specific verification, regardless of the operating conditions of the soaking plate unit 3, the 600 mm width heated object temperature difference is ± 0.6 [%] or less with respect to the heated object temperature variation target value, and ε <it does not satisfy the conditions of ε _w, ε _{h> h} satisfy the conditions of ε _w. Further, under the condition that the heat equalizing plate unit 3 is not operated under the condition of ε _h > ε _w , the emissivity difference Δε is Δε ≧ 0.8 and the 600 mm width heated object temperature difference becomes the target temperature variation target value. On the other hand, it satisfies ± 0.6 [%] or less. On the other hand, under the condition that the heat equalizing plate unit 3 is operated between the alignment state Sa and the misalignment state Sb under the condition of ε _h > ε _w , the above-mentioned 600 mm width heated heating is performed when the emissivity difference Δε is Δε ≧ 0.6. The object temperature difference is ± 0.2 [%] or less with respect to the target temperature variation target value. Therefore, by operating the soaking plate unit 3 when the emissivity difference Δε is Δε ≧ 0.6, the temperature difference of the object to be heated 2 can be further compressed with respect to the condition in which the soaking plate unit 3 is not operated. ± 0.4 [%] can be absorbed as temperature fluctuations that can occur due to environmental or temporal changes.

FIG. 5 is a diagram showing the relationship between the radiation rate of the soaking plate unit 3 and the temperature difference. Specifically, the emissivities ε _h and ε _w between the heater-side soaking plate 10 and the heated object-side soaking plate 11 and the 600 mm-width heated object temperature difference ΔT / T ₀ in a condition where the soaking plate unit 3 is not operated. %], And verification data that summarizes the emissivities ε _h and ε _w and the 600 mm width minimum heated object temperature difference ΔT / T ₀ [%] under the conditions for operating the soaking plate unit 3, FIG. At this time, the emissivity ε _h of the heater-side heat soaking plate 10 is larger than the emissivity ε _{w of the} heated object-side soaking plate 11, and the emissivity difference Δε is set to Δε = 0. However, the conditions for not operating the soaking plate unit 3 are that the openings 10a and 11a of the heater-side soaking plate 10 and the heated object-side soaking plate 11 as shown in the alignment state Sa in FIG. In this way, the registration state Sa is set. As a result of this specific verification, under the condition that the heat equalizing plate unit 3 is not operated, (ε _h , ε _w ) = (0.9, 0.3) and the 600 mm width heated object temperature difference is It satisfies ± 0.6 [%] or less with respect to the target value of temperature variation. On the other hand, under the condition for operating the soaking plate unit 3, the temperature difference of the 600 mm wide heated object is (ε _h , ε _w ) = (0.8, 0.2), (0.9, 0.3). Satisfies ± 0.2 [%] or less with respect to the target temperature variation target. Therefore, by operating the soaking plate unit 3 at ε _h ≧ 0.8, the temperature difference of the object to be heated can be further compressed with respect to the condition where the soaking plate unit 3 is not operated, and due to the surrounding environment or a change over time. ± 0.4 [%] can be absorbed as the temperature fluctuation that can occur.

  From the specific verification result of FIG. 5, it can be seen that the absolute value of the emissivity is preferably higher. This is because, in the soaking property of the article 2 to be heated, when the radiation rate of the soaking plate unit 3 is small, only a part of the radiant heat supplied from the divided heater 4 can be absorbed, and the radiant heat not absorbed is soaked. It is radiated to other furnace materials except the plate unit 3. For this reason, the radiant heat supplied by the divided heater 4 is easily dissipated in the furnace, and as a result, the heat uniformity in the furnace, and hence the heat uniformity of the article to be heated 2 is deteriorated. In the heat equalizing plate unit 3 according to the first embodiment of the present invention, a larger radiation rate difference is necessary from the viewpoint of temperature control as described above. It is desirable that the emissivity of 10 is larger than the emissivity of the heated object-side soaking plate 11.

  In general, in a normal heating mode represented by a heat treatment apparatus, a region within 80 [%] to 90 [%] on the inner side excluding both ends of a conveyance region of an object to be heated in the furnace width direction is soaked. An area to be heated is conveyed in this range. FIG. 6 shows the temperature distribution of the soaking plate when the conventional soaking plate and the conveying roller are used in the heat treatment apparatus 1. At this time, the conveyance area | region with respect to the furnace width direction of a conveyance roller is the horizontal width X along the furnace width direction inside the heat insulating material 8, and is X = 800 [mm]. FIG. 6 is a diagram showing a temperature distribution of a conventional heat equalizing plate. Specifically, FIG. 6 is verification data that summarizes the relationship between the furnace width direction distance and the soaking plate temperature at that position when the center of the furnace body 1a is 0 [mm] with respect to the furnace width direction. is there. In addition, the edge part of a conveyance area | region respond | corresponds to the position of 400 [mm] in FIG. It can be seen from FIG. 6 that the temperature distribution rapidly drops in the range of 225 [mm] to 375 [mm].

  Based on this specific verification result, the division position of the soaking plate unit 3 according to the first embodiment of the present invention is, for example, in the furnace width direction, which has a large influence on the temperature distribution deterioration in the conventional soaking plate temperature distribution. On the other hand, the conveyance area of 225 [mm] to 400 [mm] is divided and divided. Thus, when dividing the soaking plate unit 3, the temperature is divided by dividing at a position (for example, the dividing positions C1, C2) in the conventional soaking plate temperature distribution in the furnace width direction where the temperature distribution is greatly affected. The influence of the distribution deterioration can be suppressed to the minimum, and the temperature distribution in the entire furnace width direction can be equalized.

FIG. 7 is a diagram showing the relationship between the length in the short-side direction of the soaking plate 3b of the soaking plate unit 3 and the 600 mm width heated object temperature difference ΔT / T ₀ [%]. That is, the length of the opening 3a along the furnace width direction of the soaking plate unit 3 in the short direction is L _s, and the short portion of the portion having a plate thickness located between any opening 3a of the soaking plate unit 3 is used. Let L be the length including the direction length and L _s . The length L is changed to 15 [mm], 30 [mm], 60 [mm], and 100 [mm]. FIG. 7 shows the relationship between the length L at this time and the 600 mm-width heated object temperature difference ΔT / T ₀ [%]. In addition, although the part which is located between the arbitrary opening parts 3a of the said soaking | uniform-heating board unit 3 and has a plate | board thickness is the soaking | uniform-heating board 3b, on account of contrast with the opening part 3a here, non-opening part 3c Abbreviated. However, the emissivity difference Δε between the heater-side soaking plate 10 and the heated object-side soaking plate 11 is Δε = 0.6, the heater-side emissivity ε _h is ε _h = 0.8, and the number of divisions is 3 And the aperture ratio η is η = 50 [%]. From this specific verification result, L = 15 [mm], 30 [mm], and 60 [mm] satisfy ± 0.6 [%] or less with respect to the target temperature variation target value.

  From the above, the range of the length L, which is the sum of the opening 3a and the non-opening 3c of the soaking plate unit 3, is preferably 15 [mm] ≦ L ≦ 60 [mm].

The aperture ratio of the opening portions 3a of the heat equalizing plate unit 3, the length including a short direction length and the L _s of the non-opening portion 3c is L, it is given by the following formula the opening ratio as eta. However, the emissivity difference Δε between the heater-side soaking plate 10 and the heated object-side soaking plate 11 is Δε = 0.6, the heater-side emissivity ε _h is ε _h = 0.8, and the number of divisions is 3 And

η = L _s / L × 100

However,
η: Opening ratio [%] of the opening 3a of the heat equalizing plate unit 3;
L _s : The length in the short direction [mm] of the opening 3 a of the heat equalizing plate unit 3,
L: short direction length and the length including the L _s of the non-opening portion 3c of the heat equalizing plate unit 3 and [mm].

FIG. 8 is a diagram showing the relationship between the opening 3a of the heat equalizing plate unit 3 and the opening ratio. That is, a 600 mm width heated object when the aperture ratio η of the heat equalizing plate unit 3 defined by the above equation is changed to η = 0 [%], 25 [%], 50 [%], and 75 [%]. FIG. 8 shows verification data that summarizes the relationship with the temperature difference ΔT / T ₀ [%]. However, η = 0 [%] indicates a conventional heat equalizing plate in which the opening 3a of the heat equalizing plate unit 3 is not provided. As a result of this specific verification, L = 25 [%] and 50 [%] satisfy ± 0.6 [%] or less with respect to the target temperature variation target value.

  From the above, the range of the aperture ratio η of the soaking plate unit 3 is preferably 25 [%] ≦ η ≦ 50 [%].

  FIG. 9 is a diagram showing a state when the heated object-side heat equalizing plate 11 of the heat equalizing plate unit 3 is slid and moved with respect to the heater-side heat equalizing plate 10 of the heat equalizing plate unit 3. At this time, the opening ratio after sliding shown in FIG.

Opening ratio of the opening of the heat equalizing plate unit at the center of the furnace body 1a: η ′ = (L _s −S _m ) / L × 100
Opening ratio of the opening of the soaking plate unit on the furnace wall side constituting the furnace body 1a: η ′ = (L _s −S _w ) / L × 100

However,
η ′: The opening ratio [%] of the opening 3a of the heat equalizing plate unit 3;
L _s : The length in the short direction [mm] of the opening 3 a of the heat equalizing plate unit 3,
L: the length in the short direction of the non-opening portion 3c of the heat equalizing plate unit 3 and the length [mm] including the L _s ,
S _m : The sliding movement amount [mm] of the heater-side heat equalizing plate 10 or the heated object-side heat equalizing plate 11 of the heat equalizing plate unit 3 at the center of the furnace body 1a,
S _w : The sliding movement amount [mm] of the heater-side heat equalizing plate 10 or the heated object-side heat equalizing plate 11 of the heat equalizing plate unit 3 on the furnace wall side.

The soaking plate unit 3 according to the first embodiment of the present invention includes a heater-side soaking plate 11 with respect to the heater-side soaking plate 10 or a heater-side soaking plate with respect to the heating-side soaking plate 11. The state of the opening ratio η ′ = 50 [%] when the hot plate 10 is slid by L _s / 2 is used as the initial state. As shown in FIG. 9, by approaching the opening ratio η ′ = 50 [%] in the initial state to the state of the opening ratio η ′ = 0 [%], a low emissivity area that receives the radiant heat of the heater, Since the high emissivity area for the next radiation and the heat radiation surface area increase, the temperature of the soaking plate unit 3 decreases. Similarly, by approaching the opening ratio η ′ = 50 [%] in the initial state to the state of the opening ratio η ′ = 100 [%], a low emissivity area for receiving the heater radiant heat and a high secondary radiation amount are obtained. Since the emissivity area and the heat radiation surface area decrease, the temperature of the soaking plate unit 3 increases.

  FIG. 10 is a diagram illustrating an example of an opening operation pattern (temperature drop portion) of the heat equalizing plate unit 3. In general, the article to be heated 2 is heated by a temperature profile that is configured by a process of a heating unit, a temperature keeping unit, and a cooling unit. The temperature distribution in the furnace width direction of the heat treatment apparatus 1 is such that the end side of the furnace body 1a is easily heated and the center part of the furnace body 1a is not easily heated in the temperature rising process of the heating section. On the other hand, in the cooling part, the central part of the furnace body 1a is difficult to cool and the furnace wall side is easy to cool. These are due to the fact that the material has a certain heat capacity. As a condition for operating the soaking plate unit 3 according to the first embodiment of the present invention, for example, in the temperature lowering part, the center part of the furnace body 1a is high temperature and the furnace wall side is low temperature. The heater side heat equalizing plate 10 and the heated object side heat equalizing plate 11 on the furnace wall side divided in the furnace width direction, and the heater side heat equalizing plate 10 and the heated object side heat equalizing plate in the center of the furnace body 1a. 11, the opening ratio η ′ of the openings 10 a, 11 a of the divided soaking plates 10, 11 on the furnace wall side is increased, and the openings 10 a, 11 a of the divided soaking plates 10, 11 at the center of the furnace body 1 a are used. By reducing the opening ratio η ′, the temperature difference in the soaking plate in the furnace width direction can be reduced, and the radiant heat that is radiated from the soaking plate unit 3 can be made uniform. The product 2 can be soaked.

This can be achieved, for example, with the following configuration. That is, the soaking plate unit 3 is divided into a center soaking plate unit 3 and a soaking plate unit 3 on both sides of the center soaking plate unit 3 (first furnace wall side (for example, FIG. 1A)). Similarly, the soaking plate support frame 7 is divided into three parts, the soaking plate unit 3 on the left furnace wall side) and the soaking plate unit 3 on the second furnace wall side (for example, the right furnace wall side in FIG. 1A). The central heat equalizing plate support frame 7 and the furnace wall side on both sides sandwiching the central heat equalizing plate support frame 7, that is, the first furnace wall side (for example, the left furnace wall side in FIG. 1A). It is divided into a support frame 7 and a soaking plate support frame 7 on the second furnace wall side (for example, the right furnace wall side in FIG. 1A). The central heat equalizing plate support frame 7 that supports the central heat equalizing plate unit 3 is slidable by the cylinder driving portion 6b in the central portion. The soaking plate support frame 7 on the first furnace wall side that supports the soaking plate unit 3 on the first furnace wall side is slidable by the cylinder driving portion 6a on the first furnace wall side. The soaking plate support frame 7 on the second furnace wall side that supports the soaking plate unit 3 on the second furnace wall side is slidable by the cylinder driving portion 6c on the second furnace wall side. Therefore, the opening 10a of the heater side heat equalizing plate 10 of the heat equalizing plate unit 3 on the first or second furnace wall side is covered by driving of the cylinder driving portions 6a and 6c on the first or second furnace wall side. If the opening part 11a of the heated object side heat equalizing plate 11 is made to coincide or is slid so as to substantially coincide, the openings of the opening parts 10a, 11a of the divided heat equalizing plates 10, 11 on the first or second furnace wall side The ratio η ′ can be increased (see the state Sd in FIG. 10). On the other hand, the opening 11a of the heated object-side heat equalizing plate 11 is moved to L _s with respect to the opening 10a of the heater-side heat equalizing plate 10 of the central heat-uniforming plate unit 3 by driving the central cylinder driving portion 6b. For example, if both the openings 10a and 11a are slid so as to be closed, the opening ratio η ′ of the openings 10a and 11a of the divided heat equalizing plates 10 and 11 at the center can be reduced. Yes (see state Sd in FIG. 10). The state Sc in FIG. 10 is obtained by driving the first and second furnace wall sides and the central cylinder drive portions 6a, 6c, and 6b, so that the first and second furnace wall sides and the central heat plate unit 3 are provided. The opening part 11a of the to-be-heated material side soaking plate 11 is shifted by L _s / 2 with respect to the opening part 10a of the heater side soaking plate 10.

FIG. 11 is a diagram showing the relationship between the operating state of the opening 3a of the soaking plate unit 3 and the temperature difference. That is, when the central portion of the furnace body 1a is high temperature and the furnace wall side is low temperature, the sliding movement amount of the heated object-side heat equalizing plate 10 of the heat equalizing plate unit 3 in the central portion of the furnace body 1a is S _m , When the sliding movement amount of the heated object-side heat equalizing plate 11 of the furnace wall-side heat equalizing plate unit 3 is S _w , (S _m , S _w ) = (0, 0), (10, 0), (20 , 0), (30, 0), (0, 30) and 600 mm width heated object temperature difference ΔT / T ₀ [%] when the slide movement amount is changed, FIG. However, the emissivity difference Δε between the heater-side soaking plate 10 and the heated object-side soaking plate 11 is Δε = 0.6, the heater-side emissivity ε _h is ε _h = 0.8, and the number of divisions is 3. The sum L of the opening 3a and the non-opening 3c is L = 30 [mm], and the opening ratio η of the soaking plate unit 3 is η = 50 [%]. As a result of this specific verification, in (S _m , S _w ) = (10, 0), (20, 0), (30, 0), ± 0.6 [ %] Satisfies the following.

Therefore, when the slide movement amount S _w of the heated object side heat equalizing plate 11 is S _w = 0, the slide moving amount S _m of the heated object side heat equalizing plate 10 is preferably 10 ≦ S _m ≦ 30.

  According to the heat treatment apparatus 1 according to the first embodiment of the present invention, the heat equalizing plate unit 3 is interposed between the divided heater 4 and the object to be heated 2, and further, the objects to be heated of the plurality of heat equalizing plate units 3. The side heat equalizing plate 11 is individually slid in the furnace width direction by the cylinder driving units 6a, 6b, and 6c with respect to the heater side heat equalizing plate 10, thereby making the radiant heat from the divided heater 4 uniform and transporting. The temperature variation in the furnace width direction of the article to be heated 2 conveyed by the roller 5 can be reduced. Therefore, the heat treatment can be performed uniformly regardless of the furnace wall diffused heat or the ambient environment of the furnace body 1a and the change in the furnace temperature due to the temporal change of the furnace material or the type of the article 2 to be heated.

(Second Embodiment)
FIG. 12 is a diagram illustrating the configuration of the heat equalizing plate unit 3T according to the second embodiment of the present invention. In the heat treatment apparatus 1, according to the first embodiment of the present invention, a plurality of divided heaters (not shown) and a soaking plate unit 3T are divided in parallel with respect to the furnace width direction. , The number of the soaking plate units 3T is made to correspond.

Multiple contrast, soaking plate unit 3T in the second embodiment of the present invention, unlike the configuration of the first embodiment, in parallel with the divided heater and the heat equalizing plate unit 3T is the conveying direction D _b The number of divided heaters 3T is made to correspond to the number of divided heaters. Usually, since a continuous furnace represented by a heat treatment apparatus performs continuous conveyance, the difference in heat history received by the article to be heated with respect to the conveyance direction is small. However, intermittent conveyance method, such as intermittent furnaces, for example, generally, when the transfer method at constant pitch (fixed period) to the conveying direction D _b, instead of the furnace width direction, the in the conveying direction D _b since temperature differences depending on the position of the heated object 2 occurs, the temperature difference suppressing means in the conveying direction D _b is determined.

Therefore, as described above, in a situation where the temperature difference occurs, divided and the soaking plate unit 3T according to a second embodiment of the present invention with respect to the conveying direction D _b arranged with respect to the conveying direction D _b, by a driving unit (not shown), by sliding movement, it is possible to suppress the temperature difference with respect to the conveying direction D _b. Note that the heater 4T and the soaking plate unit 3T shown in FIGS. 1A and 1B are not limited to the upper part of the object to be heated 2, and may be arranged only in the lower part or both in the upper and lower parts. .

  It is to be noted that, by appropriately combining arbitrary embodiments of the various embodiments described above, the effects possessed by them can be produced.

  The heat treatment apparatus according to the present invention can heat-treat uniformly regardless of the furnace wall radiated heat or the ambient environment of the furnace body and the fluctuation of the furnace temperature due to the aging of the furnace material or the kind of the object to be heated. It is useful as a furnace for heat treatment such as a curing furnace or a reflow furnace.

DESCRIPTION OF SYMBOLS 1 Heat processing apparatus 1a Furnace body 2 To-be-heated object 3,3T Soaking plate unit 3a Opening part 3b Soaking plate 3c Non-opening part 4 Dividing heater 5 Conveyance rollers 6a, 6b, 6c Hydraulic cylinder 7 Soaking plate unit support frame 8 Heat insulating material 9 Conveying roller support base 10 Heater side heat equalizing plate 10a Opening 11 Heated object side heat equalizing plate 11a Opening 20 Heat treatment furnaces 21, 22 Furnace wall 23 Heaters 24, 25 Furnace wall 26 Silicon plate

Claims (3)

A furnace body for heat-treating an object to be heated in an internal space;
A heat source inside the furnace body;
In a heat treatment apparatus having a soaking plate unit that secondaryly radiates radiation from the heat source between the heated object and the heat source and soaks the heated object.
In the heat equalizing plate unit, a heat equalizing plate provided with a plurality of rectangular openings is arranged in the furnace width direction orthogonal to the conveying direction of the object to be heated, and the longitudinal direction of each opening is the conveying And the transverse direction of each opening is arranged in the furnace width direction, and the soaking plate includes a heat source side soaking plate close to the heat source, and the object to be heated far from the heat source. The heat source side heat equalizing plate and the heated object side heat equalizing plate are in contact with each other in the furnace body vertical direction orthogonal to the transport direction and the furnace width direction. When the emissivity of the surface of the heat source side soaking plate is ε _h and the emissivity of the surface of the heated object side soaking plate is ε _w , Δε = | ε _{h-epsilon w} | 0.6 emissivity difference [Delta] [epsilon] ≧ represented by, and a epsilon _h ≧ 0.8, the soaking plate unit Against chamber width direction orthogonal to the conveying direction, it is divided into a plurality of thirds or more,
Further, the heat treatment apparatus slides the heat source side heat equalizing plate and the heated object side heat equalizing plate relatively in the furnace width direction so that the opening of the heat source side heat equalizing plate and the heated object side A heat treatment apparatus comprising a drive unit that moves between a state in which the phase with the opening of the heat equalizing plate coincides with a state in which the phase shifts.   2. The heat treatment apparatus according to claim 1, wherein an opening ratio η of the opening of the soaking plate unit is in a range of 25 [%] ≦ η ≦ 50 [%].   The heat treatment apparatus according to claim 2, wherein the pitch of the openings of the heat equalizing plate unit is in a range of 15 [mm] ≤ L ≤ 60 [mm].

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