TW202004111A - Heat-treating furnace - Google Patents

Abstract

This heat-treating furnace is for heat-treating an object to be treated. The heat-treating furnace is provided with: a heat treatment part provided with a heat treatment space where heat treatment is applied to the object to be treated; a plurality of conveyor rollers which are disposed in the heat treatment part and on which the object being treated is carried from one end to the other end of the heat treatment space; and a drive device for driving the plurality of conveyor rollers. Each of the conveyor rollers is configured to satisfy the relation: amount of deflection [delta] ≥ amount of warpage Z, wherein Z represents the amount of warpage of the conveyor roller in a no-load state in which no to-be-treated object is placed thereon, and [delta] represents the amount of deflection of the conveyor roller in a loaded state in which the to-be-treated object is placed thereon.

Description

Heat treatment furnace

The technology disclosed in this specification relates to a heat treatment furnace that heat-treats an object.

A heat treatment furnace (for example, a roller hearth kiln, etc.) is used to heat treat the object. This heat treatment furnace system includes a plurality of conveying rollers, and the object to be processed is conveyed by rotating the conveying roller while the object to be processed is placed on the conveying roller. For example, Japanese Patent Laid-Open No. 2015-64189 discloses an example of a heat treatment furnace.

[Problems to be solved by the invention]

In this heat treatment furnace, in order to improve productivity, a plurality of objects to be processed are perpendicular to the conveying direction (hereinafter, also referred to as the first direction) and horizontal direction (hereinafter, also referred to as the second direction) on the conveying roller Place them side by side and transport these multiple objects simultaneously. In this case, a plurality of objects to be processed are simultaneously carried into the heat treatment furnace and transported in a state where the treatment target systems are juxtaposed in the second direction. However, the conveying roller may be bent during manufacturing. When the conveying roller is bent when the object is conveyed, the contact area between the object and the conveying roller becomes narrow. As a result, the conveyance of the processed object becomes unstable, and the conveyed object is inclined during the conveyance. Especially in the heat treatment furnace with a long transport distance of the object to be processed, this problem is remarkable. When the object to be processed is tilted and transported, the object to be processed is distorted, which causes problems such as obstructing the transport of other transported objects placed side by side in the second direction or colliding with the side wall in the heat treatment furnace.

This specification discloses a technique for stably transporting a plurality of objects to be processed placed side by side in a direction (second direction) that is horizontal and perpendicular to the transport direction. [Technical means to solve the problem]

The heat treatment furnace disclosed in this specification heat-treats the object. The heat treatment furnace system includes a heat treatment space for heat treatment of the treatment object, a plurality of transfer rollers arranged in the heat treatment section to transport the treatment object from one end to the other end of the heat treatment space, and a driving device for driving the plurality of rollers. For each of the plurality of rollers, in the unloaded state where the object to be processed is not loaded, the bending amount of the transport roller is taken as Z, and under the load state where the object to be processed is loaded, the deflection amount of the transport roller As δ, the relationship of the deflection amount δ≧the bending amount Z holds.

In the above heat treatment furnace, the relationship of the amount of deflection δ≧the amount of bending Z holds for each of the plurality of conveying rollers. That is, after the object to be processed is placed on the conveying drum, the amount of deflection δ tends to be greater than the amount of bending Z of the conveying drum, and the amount of deflection δ can be suppressed to be less than the amount of bending Z. Therefore, it is possible to suppress the contact area between the conveying roller and the conveyed object from being too narrow when the object is placed on the conveying roller. Therefore, the conveyance of the object to be conveyed can be stabilized.

The main features of the embodiments described below will be listed. In addition, the technical elements described below are independent technical elements, and exhibit technical utility individually or by various combinations, and are not limited to the combinations described in the claims at the time of application.

(Feature 1) In the heat treatment furnace disclosed in this specification, the bending amount Z of the conveying drum may be the maximum bending amount measured when freely supporting both ends of the conveying drum without an external force acting on the conveying drum. The deflection amount δ of the conveying roller may be the maximum deflection amount calculated when freely supporting both ends of the ideal conveying roller with a bending amount of 0, in a state where an external force generated when placing the object to be processed acts. With such a structure, the heat treatment furnace can be manufactured so that the relationship between the deflection amount δ and the bending amount Z is established, and the relationship between the deflection amount δ≧the bending amount Z can be more surely established.

(Feature 2) In the heat treatment furnace disclosed in this specification, the object to be processed may have a size supported by n (≧2) conveying rollers (specifically, the size in the conveyance direction of one object to be processed). When the mass of the object to be processed is M, the deflection amount δ of the conveying roller may be calculated as a point load or a distributed load at the position M/n where the object to be processed is placed. With such a configuration, the amount of deflection δ of the transport roller can be calculated appropriately.

(Feature 3) In the heat treatment furnace disclosed in this specification, when the axial length axis length of the conveying drum is L, the bending amount Z of the conveying drum may be 0.001 × L or less, and the deflection amount of the conveying drum δ It may be in the range of 0.001 × L to 0.0015 × L. With such a configuration, when the object to be processed is placed on the transport roller, the transport roller can flex within an appropriate range. Therefore, the conveyance of the object to be conveyed can be more stabilized. [Example]

Hereinafter, the heat treatment furnace 10 of the embodiment will be described. As shown in FIG. 1, the heat treatment furnace 10 includes a heat treatment unit 20, a carry-in unit 34, a carry-out unit 40 and a conveying device 50. The heat treatment furnace 10 heat-processes the to-be-processed object 12 when the to-be-processed object 12 is conveyed in the heat treatment part 20 by the conveyance apparatus 50.

Examples of the object to be processed 12 include a laminate in which a dielectric material (substrate) made of ceramic and an electrode are stacked, and a positive electrode material and a negative electrode material of a lithium ion battery. When the heat treatment furnace 10 is used to heat treat the ceramic laminate, these may be placed on a flat-plate-shaped carrier plate and transported in the furnace. In addition, when the positive electrode material and the negative electrode material of the lithium ion battery are heat-treated using the heat treatment furnace 10, these can be accommodated in a box-shaped casket and transported in the furnace. In the heat treatment furnace 10 of the present embodiment, a plurality of carrier plates or saggers can be loaded and transported on the transport roller 52 (described later) in a state of being aligned in the transport direction. Hereinafter, in this embodiment, the entire combination of the heat-treated substance and the carrier plate on which the heat-treated substance is placed or the sag housed in is referred to as the "object to be processed 12". In the following description, the direction in which the object to be processed 12 is transported (the direction perpendicular to the YZ plane in FIG. 1) is referred to as the “transport direction” or “first direction”, and is horizontal and perpendicular to the first direction The direction (the direction perpendicular to the XZ plane in Figure 1) is called the "second direction".

The heat treatment section 20 includes a substantially rectangular box-shaped furnace body, and a space 24 surrounded by an outer wall 22 is provided around the inside of the furnace body. An opening 26 is formed on the front end surface of the outer wall 22 (the end surface on the −X side in FIG. 1 ), and an opening 28 is formed on the rear end surface of the outer wall 22 (the end surface on the +X side in FIG. 1 ). The to-be-processed object 12 is conveyed from the opening 26 into the heat treatment part 20 by the conveyance apparatus 50, and is conveyed from the opening 28 outside the heat treatment part 20. That is, the opening 26 is used as a carrying-in port of the heat treatment section 20, and the opening 28 is used as a carrying-out port of the heat treatment section 20.

In the space 24, a plurality of transport rollers 52 and a plurality of heaters 30, 32 are arranged. The heaters 30 are arranged at regular intervals in the conveying direction at a position above the conveying roller 52, and the heaters 32 are arranged at regular intervals in the conveying direction at a position below the conveying roller 52. As the heaters 30 and 32 generate heat, the space 24 is heated. In this embodiment, although the heaters 30 and 32 are arranged at equal intervals in the conveying direction, they are not limited to such a configuration. For example, the heater system may be appropriately changed and arranged at a desired position in accordance with the type of the object to be processed 12, the heat treatment conditions of the heat treatment unit 20, and the like. In this embodiment, although the heaters 30 and 32 are arranged in the space 24, they are not limited to such a configuration. For example, as long as the space 24 can be heated, a gas burner or the like may be provided in the space 24.

As shown in FIG. 2, in the heat treatment section 20, a plurality of objects to be processed 12 are transported in parallel in the second direction. In the present embodiment, in the heat treatment unit 20 (that is, the entire heat treatment furnace 10 ), three objects to be processed 12 are conveyed side by side in the second direction. Therefore, in the present embodiment, although the size of the heat treatment portion 20 in the second direction is larger than the size of the three parallel objects in the second direction, the size direction of the heat treatment portion 20 in the second direction is not particularly limited. The size of the heat treatment unit 20 in the second direction may be a size that can transport the object 12 to be processed in parallel in the second direction by three or more. In addition, the object to be processed 12 may be transported in parallel with more than three in the second direction, and may be transported with less than three in parallel. In addition, although the dimension of the heat treatment section 20 in the conveyance direction is approximately greater than 100 m, the dimension of the heat treatment section 20 in the conveyance direction is not particularly limited. For example, the dimension of the heat treatment section 20 in the conveyance direction may be less than 100 m, 30 m to 100 m, or more than 100 m. Moreover, the to-be-processed object 12 is divided at predetermined intervals in the conveyance direction, and is continuously carried into the heat treatment part 20. Therefore, the object to be processed 12 is not only arranged in the second direction but also in the transport direction.

The carry-in section 34 is located on the upstream side of the heat treatment section 20 (that is, on the upstream side in the conveyance direction, in the first diagram, the -X direction of the heat treatment section 20). The carrying-in unit 34 receives the object 12 to be transported from the outside of the heat treatment furnace 10 and carries the received object 12 into the space 24 of the heat treatment unit 20. The carrying-in unit 34 is provided with a conveying roller 52, and conveys the object 12 to be transported from the outside of the heat treatment furnace 10 by the conveying roller 52.

The carry-out section 40 is located on the downstream side of the heat treatment section 20 (that is, on the downstream side in the conveyance direction, in the first figure, the +X direction of the heat treatment section 20). The carrying-out unit 40 carries out the object to be processed 12 from the space 24 of the heat treatment unit 20 and transfers the object to be processed 12 to the outside of the heat treatment furnace 10. The carrying-out unit 40 is provided with a carrying roller 52, and the processed object 12 is carried out of the space 24 by the carrying roller 52.

The conveying device 50 includes a plurality of conveying rollers 52, a driving device 60, and a control device 62. The transport device 50 transports the object to be transported 12 to the loading unit 34 from the loading unit 34 to the space 24 of the heat treatment unit 20 through the opening 26. In addition, the conveying device 50 is placed in the space 24 and conveys the object 12 from the opening 26 to the opening 28. Then, the conveying device 50 conveys the object to be processed 12 from the space 24 to the carrying-out unit 40 through the opening 28. The object to be processed 12 is transported from the carrying-in unit 34 to the carrying-out unit 40 by the carrying roller 52.

The transport roller 52 is cylindrical, and its axis extends in a direction orthogonal to the transport direction. The plurality of transport rollers 52 all have the same diameter, and are arranged at regular intervals at regular intervals in the transport direction. In addition, in this embodiment, although the conveyance rollers 52 provided in the heat treatment furnace 10 all have the same diameter, they are not limited to such a configuration. The transfer rollers provided in the heat treatment section 20 all have the same diameter, and the transfer rollers provided in the transfer section 34 all have the same diameter, and the transfer rollers provided in the transfer section 40 all have the same diameter, and may be provided in the heat treatment section The diameter of the conveying drum of 20 may be different from the diameter of the conveying drum provided in the carrying-in part 34 and the carrying-out part 40. In addition, the transport roller 52 provided in the heat treatment unit 20 may be provided at a different pitch from the transport roller 52 provided in the transport unit 34 and the transport unit 40. The conveying roller 52 is rotatably supported about its axis, and is rotated by transmission of the driving force of the driven device 60. More specifically, one end of the transport roller 52 in the axial direction (the end on the +Y direction side in FIG. 2) is connected to the driving device 60, and the other end (the end on the -Y direction side in FIG. 2) is Free end. In the following description, in the axial direction of the transport roller 52, the end of the transport roller 52 connected to the driving device 60 (that is, the +Y direction side) is referred to as the "driving side". The free end side of the conveying roller 52 (that is, the side in the -Y direction) is referred to as the “driven side”. The transport roller 52 is plurally disposed in the heat treatment unit 20, the transport unit 34 and the transport unit 40. The dimension of the conveyance roller 52 in the axial direction is larger than the dimension of the heat treatment section 20 in the second direction (refer to FIG. 2 ).

The plurality of transport rollers 52 arranged in the heat treatment section 20 are designed to deflect downward by the load of the object 12 when the object 12 is placed on the transport roller 52. The roller 52 may be bent during manufacturing. The transport roller 52 system disposed in the heat treatment section 20 is designed such that when the object 12 is placed on the transport roller 52, the load of the object 12 causes the amount of deflection to be greater than the amount of bending generated during manufacturing.

In this embodiment, the amount of bending that occurs when manufacturing the transport roller 52 (hereinafter, also referred to as "the amount of bending of the transport roller 52") refers to the transport roller 52 along the axial direction (that is, the second direction Or in the Y direction), in the axial direction portion of the conveying roller 52, the amount of bending at the portion where the bending becomes the largest. In other words, in the state where the external force is not acting on the transport roller 52 (that is, the no-load state), when the two ends are freely supported, the portion of the transport roller 52 in the axial direction has the maximum bending amount Quantity. Hereinafter, the bending amount of the conveying roller 52 is referred to as Z. The bending amount Z of the transport roller 52 may be measured using a measuring device such as a micrometer, for example. Specifically, the micrometer is provided at a position in the axial direction of the transport roller 52, rotates the transport roller 52 once around the axis, and when the transport roller 52 is at the uppermost position, measures The difference in status. The same measurement is performed at a plurality of parts in the axial direction of the transport roller 52, and the bending amount of the part with the largest amount of bending may be used as the bending amount of the transport roller 52. In the present embodiment, the heat transfer section 20 is provided with a transfer roller 52 having a bending amount Z within 0.1% of the axial length L (ie, the dimension in the second direction or the Y direction) of the transfer roller 52.

In addition, the amount of deflection of the conveying roller 52 due to the load of the object 12 (hereinafter, also referred to as "deflection amount of the conveying roller 52") is referred to as the case where no deflection of the conveying roller 52 occurs at all. Next, when the object to be processed 12 is placed on the conveying roller 52, the amount of deflection at the position where the conveying roller 52 is most deflected due to the load of the object to be processed 12 is set. In other words, when the object to be processed 12 is placed on the ideal conveying roller 52 with a bending amount of 0 and the object 12 is freely supported at both ends, an external force (virtual external force) acts on the object to be processed 12 The load makes the amount of deflection of the position where the transport roller 52 deflects most. Hereinafter, the amount of deflection of the transport roller 52 is referred to as δ. The amount of deflection δ of the transport roller 52 is calculated based on the material and shape of the transport roller 52 and the mass of the object 12 to be processed. The deflection amount δ of the transport roller 52 can use a theoretical value based on calculation, and the calculation method thereof is not particularly limited to those exemplified below. Furthermore, the object to be processed 12 is actually placed on the conveying roller 52, and the amount of deflection δ at this time may be measured.

Here, an example of a calculation method for calculating the deflection amount δ of the transfer drum 52 will be described. As shown in FIG. 3, the conveying roller 52 can be divided into areas A and B on the end side where the object 12 is not placed and an area C in the center where the object 12 is placed in the axial direction. When the deflection amount δ of the transport roller 52 is calculated, the mass M of the object 12 to be processed within the range of the area C acts as an equal distribution load. Here, the mass M of the object to be processed 12 is the mass of the plurality of objects to be processed 12 juxtaposed in the second direction when the object to be processed 12 is placed in parallel in the second direction (ie, the Y direction) sum. For example, in FIG. 3, the mass M of the object to be processed 12 is the sum of the masses of the three objects to be processed 12 juxtaposed in the second direction. In addition, when the object to be processed 12 is placed on the transport roller 52, the object to be processed 12 is supported via n (n system is an integer, n≧2) number of transport rollers 52. When the number of the conveying rollers 52 supporting the object to be processed 12 changes according to the mounting state of the object to be processed 12, the minimum number is regarded as the n value. For example, in FIG. 1, the object to be processed 12 is supported via three transport rollers 52. However, depending on the placement state of the object to be processed 12 (for example, in the case of displacement in the conveyance direction (X direction)), the object to be processed 12 can be brought into a state supported by the four conveyance rollers 52. That is, in the first diagram, the object 12 is supported by three to four conveying rollers 52. Therefore, the value of n is the smallest number of 3. The amount of deflection δ of the conveying roller 52 is calculated as the amount of equal distribution load acting on M/n in the field C. In addition, when calculating the amount of deflection δ of the transport roller 52, it may be possible to consider the deflection of the transport roller 52 due to its own weight. Thereby, the deflection amount δ of the conveying roller 52 can be calculated more accurately. Further, as the mass M of the object 12 to act as a point distribution load, the amount of deflection δ of the transport roller 52 may be calculated. In addition, the amount of deflection δ of the transport roller 52 may be calculated as the amount installed at room temperature. In the present embodiment, the transport roller 52 arranged in the heat treatment section 20 has a deflection amount δ of 0.1% to 0.15 of the axial length of the transport roller 52 (ie, the dimension in the second direction or the Y direction) L Way design.

In addition, the load system acting on the conveying roller 52 changes according to the state of the conveying roller 52 (for example, the position where the maximum bending occurs and the amount of bending, etc.) or the temperature of the conveying roller 52. Therefore, the actual deflection amount δ of the transport roller 52 generated during the transportation is different from the deflection amount calculated by the above calculation method. However, when the object 12 is heat-treated in the heat treatment furnace 10, the object 12 is continuously put into the heat treatment furnace 10, and the bending amount of the conveying roller 52 is also suppressed to 0.1% of the total length of the shaft length L Within the smaller value. For these reasons, even if the amount of deflection δ is calculated based on the ideal state as described above, it is possible to appropriately stabilize the conveyance of the object to be conveyed.

In the heat treatment furnace 10 of the present embodiment, in the heat treatment section 20, the conveying roller 52 is arranged so that the relationship of the amount of deflection δ≧the amount of bending Z is established. Therefore, in the heat treatment section 20, when the object to be processed 12 is placed on the conveying roller 52, the conveying roller 52 is not in a bent state, is slightly bent, or is neither bent nor bent. In addition, as described above, the amount of deflection actually generated in the transport drum 52 is different from the amount of deflection δ calculated at the time of design. Therefore, depending on the situation, there may be a case where (the actual amount of deflection of the conveying roller 52 )>(the amount of bending Z of the conveying roller 52 ). However, because the design is such that the relationship of the amount of deflection δ≧the amount of bending Z is established, the conveying roller 52 is dominated by a state where it does not bend, and the distortion of the object 12 to be processed can be effectively suppressed.

In this embodiment, both ends of the conveying roller 52 are machined. That is, the driving-side end of the transport drum 52 is machined, and the driven-side end of the transport drum 52 is also machined. In order to connect to the drive device 60, the end of the conveyance roller 52 on the drive side is usually joined to a metal cover (not shown). The drive-side end of the transport roller 52 is machined to be joined to this metal cover. As a result, the deviation of the outer diameter of the drive-side end between the plurality of transport rollers 52 is relatively small. On the other hand, the end of the conveying roller 52 on the driven side is a free end. Therefore, in the conventional conveying drum, the end on the driven side is not machined. Therefore, the end on the driven side is between a plurality of transport rollers, the outer diameter size varies greatly, and the transport speed of the object 12 disposed on the driving side and the transport of the object 12 disposed on the driven side There is a difference between speeds. As a result, there may be a problem of obstructing the transportation of the other objects to be processed 12 placed side by side in the second direction or colliding with the side wall in the heat treatment furnace 10. The transport roller 52 of this embodiment is not only machined on the drive side but also on the driven side. Therefore, between the plurality of conveying rollers 52, the deviation of the outer diameter of any one of the end on the driving side and the end on the driven side is reduced, and the conveying speed of the object 12 disposed on the driving side can be suppressed. There is a difference in the transfer speed of the processed object 12 disposed on the driven side. Therefore, it is possible to suppress the difference in the conveyance speeds of the plurality of objects 12 arranged in parallel in the second direction, and it is possible to suppress the plurality of objects 12 arranged in parallel in the second direction from being distorted and being conveyed. Moreover, in this embodiment, although the drive-side end of the conveyance drum 52 is machined, and the driven-side end of the conveyance drum 52 is also machined, it is not limited to such a configuration. The transport roller 52 may be designed so that the relationship of the deflection amount δ≧the bending amount Z is established, and the end of the transport roller 52 on the driven side may not be machined.

The drive device 60 (refer to FIG. 1) is a drive device (for example, a motor) that drives the transport roller 52. The driving device 60 is connected to the conveying roller 52 through a power transmission mechanism. When the driving force of the driving device 60 is transmitted to the conveying drum 52 through the power transmission mechanism, the conveying drum 52 rotates. As the power transmission mechanism, a known power transmission mechanism can be used, for example, a mechanism using a sprocket and a chain. The driving device 60 drives each transport roller 52 so that the transport roller 52 rotates at approximately the same speed. The driving device 60 is controlled by the control device 62.

Next, the operation of the heat treatment furnace 10 when the object 12 is heat-treated will be described. In order to heat-treat the object 12, first, the heaters 30 and 32 are actuated so that the ambient temperature of the space 24 becomes the set temperature. Next, the three to-be-processed objects 12 are each moved from the outside of the heat treatment furnace 10 to the transfer drum 52 provided in the transfer part 34. At this time, the object to be processed 12 is placed three in parallel in the second direction. Next, the driving device 60 is actuated, and the three to-be-processed objects 12 aligned in the second direction are transported from the loading portion 34 through the opening 26 to the space 24 of the heat treatment portion 20. The object 12 to be transported into the space 24 is transported from the opening 26 to the opening 28 through the space 24. Thus, the object 12 is heat-treated. Then, the object 12 to be heat-treated is transported to the transport unit 40 through the opening 28 and transported out from the transport unit 40.

The roller 52 may be bent during manufacturing. When the object to be processed 12 is placed on the conveying roller 52, the conveying roller 52 deflects due to the mass of the object to be processed 12, and the amount of deflection is based on the mass of the object to be processed 12 and the placement position of the object to be processed 12 The material, shape, etc. of the conveying roller 52 are determined. However, when the amount of bending of the conveying roller 52 is greater than the amount of deflection, even if the conveying roller 52 is flexed by placing the object 12 on the conveying roller 52, the conveying roller 52 on which the object 12 is placed may become The situation of the bent state. When the conveying roller 52 becomes curved even when the object 12 is placed, the contact area between the lower surface of the object 12 and the conveying roller 52 changes greatly as the conveying roller 52 rotates. Specifically, as shown in FIG. 4( a ), when the conveying roller 52 is located at the downward rotation position of the conveying roller 52 in the bending direction, the contact area between the conveying roller 52 and the object 12 is relatively wide. That is, the object to be processed 12 comes into contact with the transport roller 52 in the vicinity of both ends in the Y direction. On the other hand, as shown in FIG. 4( b ), when the conveying roller 52 is located at the rotational position of the conveying roller 52 in the upward direction of the bending direction, the contact area between the conveying roller 52 and the object 12 is narrowed. That is, the object to be processed 12 contacts the conveying roller 52 only in the vicinity of the center in the Y direction. Therefore, when the conveying roller 52 becomes curved even when the object 12 is placed, the contact area of the conveying roller 52 and the object 12 changes periodically, and the object 12 is not stable when conveyed by the conveying roller 52 In this state, the object to be processed 12 is easily distorted.

In the present embodiment, in the heat treatment section 20, the conveying drum 52 in which the relationship of the amount of deflection δ≧the amount of bending Z is arranged is arranged. Therefore, even if the conveying roller 52 is bent, when the object to be processed 12 is placed on the conveying roller 52, the conveying roller 52 is flexed downward. That is, in the present embodiment, when the object to be processed 12 is placed on the conveying roller 52, it is always in the state shown in FIG. 4(a) (the state of being bent), or the state of being neither bent nor bent Without the state shown in Figure 4(b) (bent state). Therefore, it is possible to suppress the contact area between the conveying roller 52 and the object 12 to be narrowed. Therefore, it is possible to suppress the state where the conveying of the object 12 becomes unstable due to the conveying roller 52, and the object 12 can be stably conveyed.

In addition, according to experiments conducted by the present inventors, by making the amount of deflection δ of the transport roller 52 disposed in the heat treatment section 20 the axial length of the transport roller 52 (that is, the dimension in the second direction or the Y direction) L From 0.1% to 0.15%, it is confirmed that the object 12 to be processed can be stably transported. As shown in FIG. 5, in Experimental Examples 1 to 5, the furnace length (the length in the transport direction of the heat treatment unit 20), the load applied to one transport roller 52, the shaft length L of the transport roller 52, and the transport roller The heat treatment furnace 10 having a different deflection amount 52 of 52 transports the object 12 to be processed. The heat treatment furnaces of Experimental Examples 1 and 2 have a length of about 50 m, and the heat treatment furnaces of Experimental Examples 3 to 5 have a length of about 100 m. In the experiment, the transport roller 52 with an outer diameter of 40 mm was used. Moreover, the conveyance roller 52 whose bending amount Z is within 0.1% of the axial length of the conveyance roller 52 (that is, the dimension in the second direction or the Y direction) L is used.

The load applied to the object 12 to be transported by the one transport roller 52 is determined by the mass of the object 12 (ie, the sum of the masses of the plurality of objects 12 aligned in the second direction) and supporting the transport of one object 12 The number of rollers 52 is calculated. For example, in Experimental Example 1, the object 12 with a mass of approximately 11.26 kg was transported in parallel in six directions in the second direction. In addition, the object to be processed 12 is supported by the four transport rollers 52. Therefore, in Experimental Example 1, the load applied to the object 12 to be transported to the one transport roller 52 was calculated to be about 17 kg. When these six processed objects 12 are placed side by side on the transport roller 52 having a shaft length L of 3100 mm, the amount of deflection δ of the transport roller 52 is calculated as the amount of distributed load acting on the transport roller 52 and the like. As a result, in Experimental Example 1, the amount of deflection δ of the transport roller 52 was calculated to be 3.5 mm. Since the axial length L of the conveying roller 52 is 3100 mm, the deflection amount δ of the conveying roller 52 is approximately 0.11% of the axial length L of the conveying roller 52, and is between 0.1% and 0.15%. When the to-be-processed object 12 was conveyed by the heat treatment furnace 10 of the experimental example 1, the to-be-processed object 12 was conveyed with almost no distortion (the conveyance evaluation in FIG. 5 is ○), and it was confirmed that the to-be-processed object 12 was stably conveyed.

The deflection amount δ of the transport roller 52 was calculated in the same manner as in Experimental Example 1. In Experimental Example 2, the deflection amount δ of the transport roller 52 was calculated to be 2.5 mm, and it was the axial length L of the transport roller 52 3000mm) about 0.08%. That is, in the heat treatment furnace 10 of Experimental Example 2, the deflection amount δ of the transfer drum 52 is less than 0.1% of the axial length L of the transfer drum 52, and is not between 0.1% and 0.15%. When the to-be-processed object 12 is conveyed by the heat treatment furnace 10 of Experimental Example 2, the to-be-processed object 12 is slightly distorted and conveyed (the conveyance evaluation in FIG. 5 is Δ), and it cannot be said that the to-be-processed object 12 is stably conveyed. Therefore, according to the results of Experimental Examples 1 and 2, in the heat treatment furnace 10 having a furnace length of about 50 m, the deflection amount δ of the transfer drum 52 is between 0.1% and 0.15% of the axial length L of the transfer drum 52, Compared with the case where the amount of deflection δ of the conveying roller 52 is less than 0.1% of the axial length L of the conveying roller 52, it is confirmed that the object 12 to be processed can be stably conveyed.

In addition, as shown in Experimental Examples 3 to 5, the same experiment was also performed in the heat treatment furnace 10 having a furnace length of about 100 m. The deflection amount δ of the transport roller 52 was calculated in the same manner as in Experimental Example 1. In Experimental Example 3, the deflection amount δ of the transport roller 52 was calculated to be 4.5 mm, and it was the axial length L of the transport roller 52 3300mm) about 0.14%. In Experimental Example 4, the amount of deflection δ of the transport roller 52 was calculated to be 3.0 mm, and was about 0.11% of the axial length L of the transport roller 52 (2800 mm in Experimental Example 4). In Experimental Example 5, the deflection amount δ of the transport roller 52 was calculated to be 2.0 mm, and was about 0.07% of the axial length L of the transport roller 52 (2800 mm in Experimental Example 5). That is, in the heat treatment furnaces 10 of Experimental Examples 3 and 4, the deflection amount δ of the conveying roller 52 is between 0.1% and 0.15%, and in the heat treatment furnace 10 of Experimental Example 5, the deflection amount δ of the conveying roller 52 It is less than 0.1%. When the to-be-processed object 12 is conveyed by the heat treatment furnace 10 of Experimental Examples 3 to 5, in the heat-treatment furnace 10 of Experimental Examples 3 and 4, the to-be-processed object 12 is conveyed almost without distortion (the conveyance evaluation in FIG. 5 is ○), the object to be processed 12 is stably transported. On the other hand, in the heat treatment furnace 10 of Experimental Example 5, the object 12 was transported with distortion (the transport evaluation in FIG. 5 is ×), and the object 12 was not transported stably. Therefore, from the results of Experimental Examples 3 to 5, in the heat treatment furnace 10 having a furnace length of about 100 m, the deflection amount δ of the transport roller 52 is between 0.1% and 0.15% of the axial length L of the transport roller 52 Next, as compared with the case where the amount of deflection δ of the conveying roller 52 is less than 0.1% of the axial length L of the conveying roller 52, it is confirmed that the object 12 to be processed can be stably conveyed.

In the above, specific examples of the technology disclosed in this specification have been described in detail, but these are only examples and do not limit the scope of patent claims. The technology described in the scope of the patent request includes various variations and modifications of the specific examples exemplified above. In addition, the technical elements described in this specification or the drawings exhibit technical usefulness individually or in various combinations, and are not limited to the combinations described in the claims at the time of application.

10‧‧‧heat treatment furnace 12‧‧‧ object to be processed 20‧‧‧Heat Treatment Department 22‧‧‧Outer wall 24‧‧‧Space 26, 28‧‧‧ opening 30, 32‧‧‧ heater 34‧‧‧ Move in 40‧‧‧Move out of the department 50‧‧‧Conveying device 52‧‧‧Transfer roller 60‧‧‧Drive device 62‧‧‧Control device A, B, C L‧‧‧Shaft length

FIG. 1 is a diagram showing a schematic configuration of the heat treatment furnace according to the embodiment, and is a longitudinal cross-sectional view when the heat treatment furnace is cut in a plane parallel to the conveyance direction of the object to be processed. Figure 2 is a cross-sectional view taken along the line II-II of Figure 1. FIG. 3 is a diagram showing a state where the object to be processed is placed on the conveying roller. FIG. 4 is a diagram for explaining the conveyance of the object to be processed in a state where the conveying roller is bent, (a) shows the state where the conveying roller is located below, and (b) shows the state where the conveying roller is located above. Fig. 5 shows the relationship between the bending amount of the conveying drum and the stable conveyance of the object, and shows the experimental conditions (various numerical values) and the experimental results.

10‧‧‧heat treatment furnace

12‧‧‧ object to be processed

20‧‧‧Heat Treatment Department

22‧‧‧Outer wall

24‧‧‧Space

26, 28‧‧‧ opening

30, 32‧‧‧ heater

34‧‧‧ Move in

40‧‧‧Move out of the department

50‧‧‧Conveying device

52‧‧‧Transfer roller

60‧‧‧Drive device

62‧‧‧Control device

Claims (4)

A heat treatment furnace is a heat treatment furnace for heat treatment of the object, including: The heat treatment section includes a heat treatment space for heat treating the aforementioned object; A plurality of transport rollers, which are arranged in the heat treatment section, and transport the object to be treated from one end to the other end of the heat treatment space; and The driving device drives the plurality of conveying rollers, In each of the plurality of transport rollers, when the object to be processed is not loaded, the bending amount of the transport roller is taken as Z, and the load is placed on the object to be processed The amount of deflection of the drum is δ, and the relationship of the amount of deflection δ≧the amount of bending Z is established. The heat treatment furnace according to item 1 of the scope of the patent application, wherein the bending amount Z of the conveying roller is the maximum bending measured when the two ends of the conveying roller are freely supported without an external force acting on the conveying roller the amount, The amount of deflection δ of the conveying drum is calculated by freely supporting both ends of the conveying drum in a state where an external force acts when the object to be processed is placed in an ideal conveying drum with a bending amount Z of 0. Maximum deflection. The heat treatment furnace as described in item 2 of the patent application scope, wherein the object to be processed has a size to support n (≧2) of the conveying rollers, When the mass of the object to be processed is M, the deflection amount δ of the conveying roller is calculated as a function of point load or distributed load at the position M/n where the object to be processed is placed. The heat treatment furnace according to any one of claims 1 to 3, wherein when the axial length of the conveying roller is L, the bending amount Z of the conveying roller is 0.001 × L or less, and the conveying The deflection amount δ of the drum is in the range of 0.001 × L to 0.0015 × L.

Images