TW201930802A - Heat treatment furnace and method for manufacturing same - Google Patents

Abstract

This heat treatment furnace performs a heat treatment on an object to be treated. The heat treatment furnace is provided with: a heat treatment part that is provided with a space for performing a heat treatment on the object; and a plurality of conveyance rollers that are arranged in the heat treatment part and that convey the object. Regarding the conveyance rollers installed within the prescribed range in the heat treatment part, the curvature directions of portions of the respective conveyance rollers, where the curvatures thereof are the largest when the conveyance rollers are viewed in the axial direction, change periodically.

Description

Heat treatment furnace and manufacturing method thereof

The technique disclosed in this patent specification relates to a heat treatment furnace for heat-treating a workpiece and a method of manufacturing the same.

The object to be treated is sometimes subjected to heat treatment using a heat treatment furnace (for example, a roller hearth furnace or the like). This heat treatment furnace includes a plurality of conveyance rollers, and conveys the workpiece by rotating the conveyance roller while the workpiece is placed on the conveyance roller. An example of a heat treatment furnace is disclosed in Japanese Laid-Open Patent Publication No. 2015-64189.

[Problems to be solved by the invention]

In such a heat treatment furnace, in order to improve productivity, a plurality of rollers are arranged on the conveyance roller in a direction perpendicular to the conveyance direction (hereinafter also referred to as a first direction) and horizontally (hereinafter also referred to as a second direction). The processed object and the plurality of processed objects are simultaneously carried. In this case, a plurality of objects to be processed are placed in the heat treatment furnace while being aligned in the second direction. Further, a plurality of objects to be processed are transported in a heat treatment furnace by a conveyance roller, and are then carried out from the heat treatment furnace. Since a plurality of objects to be processed arranged and arranged in the second direction are conveyed by the same conveyance roller, they are preferably carried out simultaneously from the heat treatment furnace. However, due to the bending or the like due to the weight of the workpiece or the like, there is a difference in the conveyance speed depending on which position the workpiece is placed in the conveyance roller. Therefore, there is a problem in that a plurality of objects to be processed which are arranged and placed in the second direction are not simultaneously carried out from the heat treatment furnace. This problem is remarkable especially in the heat treatment furnace in which the handling distance of the workpiece is long.

This patent specification discloses a technique in which the difference in conveyance speed of a plurality of objects to be processed which are arranged horizontally and in a direction perpendicular to the conveyance direction (second direction) is reduced.
[Means for solving the problem]

The object to be treated is heat-treated in the heat treatment furnace disclosed in this patent specification. The heat treatment furnace includes a heat treatment portion including a space for heat-treating the workpiece, and a plurality of conveyance rollers disposed in the heat treatment portion to carry the workpiece. The plurality of conveyance rollers provided in the predetermined range of the heat treatment portion periodically change the warpage direction of the portion where the warpage of the conveyance roller becomes the maximum when the conveyance roller is viewed in the axial direction.

In the heat treatment furnace described above, the warpage direction of the conveyance roller is periodically changed in a predetermined range of the heat treatment portion, and a plurality of the heat treatment furnaces can be arranged in a horizontal direction and in a direction perpendicular to the conveyance direction (second direction). The handling speed of the processed object. Therefore, it is possible to reduce the difference in the conveyance speed which is generated depending on which position (position in the second direction) the object to be processed is placed in the conveyance roller.

Further, in the method for producing a heat treatment furnace disclosed in the present specification, a heat treatment furnace is provided, the heat treatment furnace comprising: a heat treatment portion including a space for heat-treating the workpiece; and a plurality of conveyance rollers disposed in the heat treatment And carrying out the processed object; the manufacturing method of the heat treatment furnace includes: a measuring step of measuring each of the plurality of conveying rollers provided in a predetermined range of the heat treatment portion, and measuring the conveying roller when viewed along the axial direction The warpage of the conveyance roller becomes the warpage direction of the largest portion; and the installation step is such that the conveyance roller is periodically changed in the predetermined range of the heat treatment portion so as to be in the measured warpage direction.

In the above-described manufacturing method of the heat treatment furnace, the conveyance roller is set to have a measured warpage direction to be periodically changed within a predetermined range of the heat treatment portion. Therefore, the conveyance speed of the plurality of objects to be processed arranged and placed in the second direction can be adjusted, and the difference in the conveyance speed at which the workpiece is placed in the conveyance roller can be made smaller. .

The main features of the embodiments described below are listed in advance. Further, the technical elements described below are independent of each other, and are technically useful individually or in various combinations, and are not limited to the combinations described in the patent application scope when the patent is filed.

(Feature 1) The plurality of transport rollers provided in the heat treatment furnace disclosed in the present specification may be formed by a predetermined number of conveyance rollers for one cycle. The warping direction of each of the conveyance rollers that constitute one cycle may be shifted by a predetermined angle with respect to the warpage direction of the conveyance roller adjacent to the conveyance roller. According to this configuration, the conveyance speed of a plurality of objects to be processed which are arranged horizontally and in the direction perpendicular to the conveyance direction (second direction) can be appropriately adjusted. In particular, when the conveyance speed of the workpiece placed on the end side of the conveyance roller is faster than the workpiece placed in the vicinity of the center, a plurality of processed and arranged in the second direction can be processed. The difference in the handling speed of the object becomes small.

(Feature 2) The heat treatment furnace disclosed in the present specification may further include a driving device capable of simultaneously driving a plurality of conveying rollers provided in a predetermined range. Further, the driving device may maintain a state in which the warping direction of the conveying roller and the warping direction of the adjacent conveying roller are shifted by a predetermined angle, and drive a plurality of conveying rollers provided in a predetermined range. According to this configuration, the driving device simultaneously drives the plurality of conveying rollers provided in a predetermined range, whereby the warping direction of the plurality of conveying rollers set in a predetermined range and the warping direction of the adjacent conveying rollers are shifted. The state of the given angle. Therefore, the state in which the conveyance speed of the plurality of objects to be processed arranged and placed in the second direction is adjusted can be maintained.

(Feature 3) The heat treatment furnace disclosed in this patent specification may also have a predetermined angle of 90 degrees. According to this configuration, the conveyance speed of the plurality of objects to be processed arranged and conveyed in the second direction can be appropriately adjusted in accordance with the amount of bending of the conveyance rollers. In particular, when the amount of bending of the conveyance roller when the workpiece is placed on the conveyance roller is small, the difference in conveyance speed of the plurality of workpieces arranged and placed in the second direction can be made small.

(Feature 4) The heat treatment furnace disclosed in this patent specification may also have a predetermined angle of 180 degrees. According to this configuration, the conveyance speed of the plurality of objects to be processed arranged and conveyed in the second direction can be appropriately adjusted in accordance with the amount of bending of the conveyance rollers. In particular, when the amount of bending of the conveyance roller when the workpiece is placed on the conveyance roller is large, the difference in conveyance speed of the plurality of workpieces arranged and placed in the second direction can be made small.
[Examples]

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 loading unit 34 , a carry-out unit 40 , and a conveyance device 50 . In the heat treatment furnace 10, the workpiece 12 is conveyed between the workpieces 12 in the heat treatment unit 20 by the conveyance device 50, and the workpiece 12 is heat-treated.

The material to be processed 12 is, for example, a laminate in which a dielectric body (base material) made of ceramics and an electrode are laminated, or a positive electrode material or a negative electrode material of a lithium ion battery. When the ceramic laminate is heat-treated using the heat treatment furnace 10, the objects to be processed are placed in a flat carrier plate and conveyed in the furnace. Further, when the positive electrode material or the negative electrode material of the lithium ion battery is heat-treated by using the heat treatment furnace 10, the objects to be processed are stored in a box-shaped crucible and conveyed in the furnace. The heat treatment furnace 10 of the present embodiment can be conveyed in a state in which a plurality of sheet carriers or rafts are arranged in the conveyance direction on the conveyance rollers 52 (described later). Hereinafter, in the present embodiment, the entirety of the substance to be heat-treated, the carrier plate on which the material to be heat-treated, or the material containing the substance is placed is referred to as "the object to be treated 12". In the following description, the direction in which the workpiece 12 is conveyed (the direction perpendicular to the YZ plane in FIG. 1) may be referred to as "transport direction" or "first direction", and may be horizontal and perpendicular to the first direction. The direction (the direction perpendicular to the XZ plane of Fig. 1) is referred to as the "second direction".

The heat treatment unit 20 includes a substantially rectangular box-shaped furnace body, and an outer wall 22 is provided inside the furnace body to surround the surrounding space 24. An opening 26 is formed in the front end surface (the end surface on the -X side in Fig. 1) of the outer wall 22, and an opening 28 is formed in the rear end surface (the end surface on the +X side in Fig. 1) of the outer wall 22. The workpiece 12 is transported from the opening 26 into the heat treatment unit 20 by the transport device 50, and is transported from the opening 28 to the outside of the heat treatment unit 20. That is, the opening 26 is used as the carry-in port of the heat treatment portion 20, and the opening 28 is used as the carry-out port of the heat treatment portion 20.

In the space 24, a plurality of conveyance rollers 52 and a plurality of heaters 30 and 32 are disposed. The heaters 30 are disposed at a position above the conveyance roller 52 at equal intervals in the conveyance direction, and the heaters 32 are disposed at positions below the conveyance rollers 52 at equal intervals in the conveyance direction. The heaters 30, 32 are heated by heating in the space 24. Further, in the present embodiment, the heaters 30 and 32 are arranged at equal intervals in the conveyance direction, but are not limited to such a configuration. In addition, the heater may be appropriately changed to a desired position and disposed, for example, in accordance with the type of the workpiece 12 or the heat treatment condition of the heat treatment unit 20. Further, in the present embodiment, the heaters 30 and 32 are disposed in the space 24, but the configuration is not limited thereto. As long as the heating can be performed in the space 24, for example, a gas burner or the like may be provided in the space 24.

As shown in FIG. 2, in the heat treatment unit 20, a plurality of objects 12 to be processed are arranged and transported in the second direction. In the present embodiment, in the heat treatment unit 20 (that is, the entire heat treatment furnace 10), three objects 12 to be processed are arranged and conveyed in the second direction. Therefore, in the present embodiment, the dimension of the heat treatment portion 20 in the second direction is larger than the size of the three workpieces 12 arranged in the second direction, but the dimension of the heat treatment portion 20 in the second direction is not particularly large. limited. The size of the heat treatment portion 20 in the second direction may be arranged in the second direction and conveyed by more than three objects 12 to be processed. Moreover, the dimension of the heat treatment part 20 in the conveyance direction is relatively large, about 100 m, but the dimension of the heat processing part 20 in the conveyance direction is not specifically limited. For example, the dimension of the heat treatment portion 20 in the conveyance direction may be smaller than 100 m, may be 30 m to 100 m, or may be larger than 100 m. In addition, in the following description, the center side in the second direction in which the plurality of objects 12 are arranged in the second direction is referred to as "inside", and the center side in the second direction is in the side of the end (+Y direction and The -Y direction is called "outside". Further, the workpiece 12 is continuously carried into the heat treatment portion 20 at a predetermined interval. Therefore, the objects 12 to be processed are arranged not only in the second direction but also in the conveyance direction.

Further, as shown in FIG. 2, in the present embodiment, among the three objects 12 to be placed and placed in the second direction, the person placed on the +Y direction side in the second direction is regarded as the object to be processed. In the 12a, the center (inside) of the second direction is regarded as the object to be processed 12b, and the person placed on the -Y direction side in the second direction is treated as the object to be processed 12c. Hereinafter, other constituent elements may be described using letters along the word when it is necessary to distinguish the constituent elements, and the letters along the word are omitted when it is not necessary to distinguish the constituent elements, and only numbers are described.

The loading unit 34 is located on the upstream side of the heat treatment unit 20 (that is, on the upstream side in the conveyance direction, and in the -X direction of the heat treatment unit 20 in Fig. 1). The loading unit 34 receives the workpiece 12 conveyed from the outside of the heat treatment furnace 10, and carries the received workpiece 12 into the space 24 of the heat treatment unit 20. The conveyance unit 34 is provided with a conveyance roller 52, and conveys the workpiece 12 conveyed from the outside of the heat treatment furnace 10 by the conveyance roller 52.

The carry-out portion 40 is located on the downstream side of the heat treatment portion 20 (that is, on the downstream side in the conveyance direction, and in the +X direction of the heat treatment portion 20 in Fig. 1). The unloading unit 40 carries out the workpiece 12 from the space 24 of the heat treatment unit 20, and then delivers the workpiece 12 that has been carried out to the outside of the heat treatment furnace 10. In the carry-out unit 40, the conveyance roller 52 is provided, and the workpiece 12 is conveyed to the outside of the space 24 by the conveyance roller 52.

The conveying device 50 includes a plurality of conveying rollers 52, a driving device 60, and a control device 62. The conveyance device 50 conveys the workpiece 12 conveyed to the loading unit 34 from the loading unit 34 through the opening 26 into the space 24 of the heat treatment unit 20 . Further, the conveying device 50 is placed in the space 24, and conveys the workpiece 12 from the opening 26 to the opening 28. Further, the transport device 50 transports the workpiece 12 from the space 24 to the carry-out unit 40 via the opening 28 . The workpiece 12 is transported from the loading unit 34 to the carry-out unit 40 by the transport roller 52.

The conveyance roller 52 has a cylindrical shape, and its axis extends in a direction orthogonal to the conveyance direction. The plurality of transport rollers 52 all have the same diameter and are arranged at equal intervals at a fixed pitch in the transport direction. Further, the diameter of the transport roller provided in the heat treatment portion 20 may be different from the diameter of the transport roller provided in the carry-in portion 34 and the carry-out portion 40. Moreover, the conveyance roller 52 provided in the heat processing unit 20 may be disposed at a different pitch from the conveyance roller 52 provided in the loading unit 34 and the delivery unit 40. The carrying roller 52 is supported to be rotatable about its axis and rotated by the driving force of the driving device 60. The conveyance roller 52 is disposed in a plurality of branches in the heat treatment unit 20, the carry-in unit 34, and the carry-out unit 40. The dimension of the conveyance roller 52 in the axial direction is larger than the dimension of the heat treatment part 20 in the 2nd direction (refer FIG. 2).

The plurality of conveyance rollers 52 disposed in the heat treatment unit 20 are provided to adjust warpage in a plurality of portions in the axial direction of the conveyance roller 52 when the respective conveyance rollers 52 are viewed in the axial direction (that is, in the second direction or the Y direction). The warping direction of the largest portion (hereinafter also referred to as the warping direction of the conveyance roller 52). The plurality of portions in the axial direction of the conveyance roller 52 may be, for example, a portion near the center of the conveyance roller 52 and a conveyance roller 52 when the conveyance roller 52 is arranged in the second direction and a plurality of workpieces 12 are placed. A portion in the vicinity of a portion where the end portion of each of the objects 12 in the second direction contacts. In the present embodiment, as shown in FIG. 3, since the conveyance rollers 52 are arranged in the second direction and placed on the three objects to be processed 12a to 12c, the end portion side (+Y direction side) of the workpiece 12a is placed. The vicinity of the end portion is referred to as the portion A, and the vicinity of the boundary between the workpiece 12a and the workpiece 12b is referred to as the portion B, and the vicinity of the center of the conveyance roller 52 in the axial direction is referred to as the portion C, and the workpiece 12b and the workpiece are treated. The vicinity of the boundary of 12c is regarded as the portion D, and the vicinity of the end portion on the end side (-Y direction side) of the workpiece 12c is regarded as the portion E. Therefore, in the present embodiment, the warpage direction of the portion where the warpage is the largest among the five portions A to E in the axial direction of the conveyance roller 52 is regarded as the warpage direction of the conveyance roller 52. Further, in the present embodiment, the warping direction of the conveyance roller 52 is set from the warping direction of the five portions A to E in the axial direction of the conveyance roller 52, but the configuration is not limited thereto. The warping direction of the conveyance roller 52 may be set according to the warpage direction of a portion where the ratio of the conveyance roller 52 is more than five, or may be set according to the warpage direction of a portion smaller than five. Further, a plurality of portions in the axial direction may be set regardless of the position of the workpiece 12 placed on the conveyance roller 52.

In the present embodiment, the warping direction of the conveyance roller 52 disposed in the heat treatment unit 20 is adjusted in accordance with the amount of bending of the conveyance roller 52 generated when the conveyance roller 52 has placed the workpiece 12. Specifically, the warping direction of the conveyance roller 52 is set to periodically change. In other words, the conveyance roller 52 is disposed in a state in which the warping direction of the adjacent conveyance roller 52 is shifted by a predetermined angle. Specifically, when the amount of bending of the conveyance roller 52 is large, it is arranged so that the warpage direction of the adjacent conveyance roller 52 is shifted by 180 degrees. Moreover, when the amount of bending of the conveyance roller 52 is relatively small, it is arrange|positioned so that the curvature direction of the adjacent conveyance roller 52 may shift by 90 degrees. By disposing in this manner, the difference in the conveyance speed of the plurality of objects 12a to 12c arranged and placed in the second direction in the heat treatment portion 20 can be made small.

The drive unit 60 (see FIG. 1) is a drive unit (for example, a motor) that drives the conveyance roller 52. The drive unit 60 is connected to the conveyance roller 52 via a power transmission mechanism. When the driving force of the driving device 60 is transmitted to the conveying roller 52 via the power transmission mechanism, the conveying roller 52 rotates. As the power transmission mechanism, a well-known person can be used, for example, a mechanism composed of a sprocket and a chain. The drive unit 60 drives the respective conveyance rollers 52 to rotate the conveyance rollers 52 at substantially the same speed. The drive unit 60 is controlled by the control unit 62.

The plurality of conveyance rollers 52 are rotated by the driving force of the drive unit 60. In the present embodiment, the plurality of transport rollers 52 connected to the same drive unit 60 are simultaneously and at the same speed. Therefore, as described above, the plurality of conveyance rollers 52 that have been adjusted in the warpage direction of the conveyance roller 52 are rotated in a state in which the adjusted warpage direction is maintained. Further, since the conveyance rollers 52 provided in the heat treatment portion 20 are preferably rotated at the same speed and at the same speed, it is preferable to connect them to one drive unit 60. However, as shown in the heat treatment furnace 10 of the present embodiment, when the distance in the conveyance direction of the heat treatment portion 20 is relatively long, it is difficult to rotate all of the conveyance rollers 52 provided in the heat treatment portion 20 by one drive unit 60. In this case, a plurality of driving devices 60 that generate the same driving force for each of the connected conveying rollers 52 are provided, and are divided in order to drive all of the conveying rollers 52 provided in the heat treatment portion 20 with the same driving force. The conveyance roller 52 provided in the heat treatment unit 20 is connected to a plurality of drive units 60. Thereby, all of the conveyance rollers 52 provided in the heat treatment unit 20 can be rotated at the same driving force and at the same speed. At this time, the conveyance rollers 52 connected to the different driving devices 60 are sometimes shifted in timing, and are between the conveyance rollers 52 connected to the different driving devices 60 (that is, the conveyance rollers 52 at the boundary). There is a case where the adjusted warping direction cannot be maintained. Even in this case, since the conveyance roller 52 connected to the same driving device 60 can maintain the adjusted warping direction, the plurality of processed objects 12a to 12c arranged and placed in the second direction can be placed. The difference in the conveying speed of the heat treatment unit 20 is small. Further, the transport roller 52 provided in the carry-in unit 34 and the carry-out unit 40 may be connected to a drive device that generates a driving force different from the drive device 60 of the transport roller 52 provided in the heat treatment unit 20, or may be configured. It is rotated at a speed different from that of the conveyance roller 52 provided at the heat treatment section 20.

Next, a method of manufacturing the heat treatment furnace 10 will be described with reference to Figs. 3 and 4 . Further, in the present embodiment, the step of measuring the warpage direction of the conveyance roller 52 and the step of arranging the conveyance roller 52 in the heat treatment unit 20 are characterized, and in the other steps, a conventionally known procedure can be used. Therefore, in the following, only the characteristic portions of the present embodiment will be described, and the description of the other steps will be omitted.

The manufacturing method of the heat treatment furnace 10 of the present embodiment includes a measuring step of measuring a warping direction of a portion where the warpage of the conveying roller 52 becomes maximum when the conveying roller 52 is viewed in the axial direction; and a setting step of transporting The roller 52 is arranged such that the measured warping direction changes periodically.

First, by the measuring step, the warping direction of each of the plurality of conveying rollers 52 is measured as the warpage direction of the largest portion. The measurement steps were carried out in accordance with the following procedures. First, both ends of the conveying roller 52 are supported to be rotatable. For example, two V-shaped blocks are used to support both ends of the conveying roller 52.

Next, the magnitude of the warpage of each of the portions A to E in the axial direction of the conveyance roller 52 is measured using, for example, a gauge of a dial gauge. Specifically, a gauge is set in the portion A, and the conveyance roller 52 is rotated one turn around the axis, and when the conveyance roller 52 is at the uppermost position, the difference from the state in which the conveyance roller 52 is not warped is measured (hereinafter also referred to as warpage). The size). For the portions B to E, the same measurements as above were also performed. After measuring the warpage of each part A to E, the measurement results of the five parts A to E were compared, and the portion having the largest warpage was determined. Then, a mark 54 (see FIG. 4) indicating the warpage direction of the portion where the warpage is the largest is added to the end surface of the conveyance roller 52 in the axial direction. In the same manner, the warping direction of all the conveyance rollers 52 provided in the heat treatment unit 20 is measured, and a mark 54 indicating the warpage direction of the conveyance roller 52 is added to the end surface of each conveyance roller 52 in the axial direction.

The conveyance roller 52 to which the mark 54 is applied is provided in the heat treatment part 20 by the installation process. When the conveyance roller 52 is installed in the heat treatment furnace 10, it is provided by adjusting the warpage direction of each conveyance roller 52 according to the mark 54 applied to each conveyance roller 52 in the above-mentioned measurement procedure. Further, in the present embodiment, it is characterized in that the warping direction of each of the transport rollers 52 is adjusted, and the other procedures for the setting procedure are based on a conventionally known method. Therefore, other procedures regarding the setting procedure are employed. The detailed description is omitted.

As described above, the conveyance roller 52 provided in the heat treatment unit 20 is provided in accordance with the warping direction, but the installation form is based on the amount of bending of the conveyance roller 52 generated when the workpiece 12 is placed on the conveyance roller 52. different. Therefore, depending on the weight of the workpiece 12 to be heat-treated, the warpage direction of the conveyance roller 52 adjusted when the respective conveyance rollers 52 are provided is different. Specifically, when the amount of bending is large, each of the conveyance rollers 52 is provided such that the warpage direction of the conveyance roller 52 is shifted by 180° from the warpage direction of the adjacent conveyance rollers 52 (FIG. 4(b)). Moreover, when the amount of bending is small, each of the conveyance rollers 52 is provided so that the warpage direction of the conveyance roller 52 is shifted by 90 degrees from the warpage direction of the adjacent conveyance roller 52 (FIG. 4 (a)).

Next, the operation of the heat treatment furnace 10 when the workpiece 12 is subjected to heat treatment will be described. In order to heat-treat the workpiece 12, first, the heaters 30 and 32 are operated to set the ambient gas temperature of the space 24 to the set temperature. Next, the three objects 12 to be processed are respectively moved from the outside of the heat treatment furnace 10 to the conveyance rollers 52 provided on the loading unit 34. At this time, the objects 12 to be processed are arranged in the second direction and placed three. Next, the drive device 60 is operated to transport the three objects 12 arranged in the second direction from the loading unit 34 to the space 24 of the heat treatment unit 20 via the opening 26 . The workpiece 12 conveyed into the space 24 is transported from the opening 26 to the opening 28 in the space 24. Thereby, the workpiece 12 is subjected to heat treatment. Then, the workpiece 12 that has been subjected to the heat treatment is conveyed to the carry-out portion 40 through the opening 28, and is then carried out from the carry-out portion 40.

The workpiece 12 is conveyed from the loading unit 34 through the heat treatment unit 20 to the unloading unit 40 in a plurality of positions (three in the present embodiment) in the second direction. However, when the inlet of the heat treatment unit 20 is placed in a state in which the conveyance direction is aligned, a plurality of workpieces 12 are loaded, and the conveyance speed of each of the plurality of workpieces 12 varies between the conveyance of the heat treatment unit 20, and the heat treatment is performed. When the unit 20 is carried out, a plurality of objects 12 to be processed are in a state of being shifted in the conveyance direction. This shift is caused by warpage or the like generated during the manufacture of the conveyance roller 52, or by the conveyance roller 52 when the workpiece 12 is placed on the conveyance roller 52 due to the weight of the workpiece 12. Bending is produced. According to experience, it is found that the conveyance speed of the workpiece 12 placed on the outer side (end side) of the conveyance roller 52 is easy, especially when the "bending" of the conveyance roller 52 is larger than the "warpage" of the conveyance roller 52. The conveyance speed of the workpiece 12 placed on the inner side (center) of the conveyance roller 52 is faster. This is considered to be based on the reasons as shown below.

Since the conveyance roller 52 is warped or deformed at the time of manufacture, it is impossible to make all the conveyance rollers 52 provided in the heat treatment furnace 10 into the identical shape. When the "bending" of the conveying roller 52 is larger than the "warping" of the conveying roller 52, the influence of "warping" by the "bending" of the conveying roller 52 is canceled, but the diameter of the conveying roller 52 is not The conveyance speed of the workpiece 12 placed on the outer side (end side) of the conveyance roller 52 is likely to be faster than the conveyance speed of the workpiece 12 placed on the inner side (center) of the conveyance roller 52. .

This will be explained using FIG. 5. Fig. 5 is a view schematically showing the workpiece 12 placed on the six transport rollers 52. The six transport rollers 52 are arranged in the order from the upstream to the downstream (in the +X direction) in the order of the transport rollers 52a to 52f. . Further, the six transport rollers 52a to 52f have large diameters of the transport rollers 52a, 52c, and 52e, and the transport rollers 52b, 52d, and 52f have small diameters. In addition, in FIG. 5, in order to make the difference of the diameter dimension clear, the difference in the diameter dimension of the conveyance rollers 52a, 52c and 52e and the conveyance rollers 52b, 52 d and 52f is emphasized.

Here, since the conveyance roller 52 is supported at both ends, the "bending" is increased at the center and becomes smaller at the end. When the "bending" of the conveyance roller 52 is small, the workpiece 12 is only in contact with the conveyance roller 52 having a large diameter. On the other hand, when the "bending" of the conveyance roller 52 is large, the workpiece 12 is greatly bent by the conveyance roller 52 having a large diameter, and as a result, it is also in contact with the conveyance roller 52 having a small diameter.

As shown in Fig. 5 (a), the conveyance rollers 52a, 52c, and 52e are bent in the vicinity of the center of the conveyance roller 52, so that the workpiece 12b is in contact with the other conveyance rollers 52b, 52d, and 52f. In other words, the workpiece 12b is in contact with all of the conveyance rollers 52a to 52f. On the other hand, as shown in Fig. 5 (b), since the bending of the conveyance rollers 52a, 52c, and 52e is small at the end portion of the conveyance roller 52, the objects 12a and 12c and the conveyance rollers 52b, 52d, and 52f are generated. The state of no contact. Therefore, at the end of the conveyance roller 52, the conveyed objects 12a and 12c are conveyed only by the conveyance rollers 52a, 52c, and 52e having a large turning radius, and as a result, the conveyance speed of the objects 12a and 12c is increased. On the other hand, in the state shown in Fig. 5 (a), since the bending of the conveyance rollers 52a, 52c, and 52e is large, the workpiece 12b is in contact with all of the conveyance rollers 52a to 52f, and the conveyance roller 52a is lowered. The effect of the diameter of the 52f. As a result, the conveyance speed of the workpiece 12 placed on the inside of the conveyance roller 52 is slower than the conveyance speed of the workpiece 12 placed on the outer side (end side) of the conveyance roller 52.

Then, the workpiece 12 is changed in conveyance speed due to warpage, bending, and unevenness in diameter of the conveyance roller 52. Therefore, the plurality of objects 12 to be processed arranged in the second direction may be displaced in the conveyance direction between the conveyed objects 12 in the heat treatment unit 20 . In particular, as described above, in the heat treatment furnace 10 of the present embodiment, since the size of the heat treatment unit 20 in the conveyance direction is relatively long, the plurality of objects 12 to be processed and transported in the second direction are easily shifted in the conveyance direction. . When the plurality of objects 12 to be processed are not aligned in the second direction in the carry-out portion 40, it is difficult to carry out the plurality of objects 12 to be processed outside the heat treatment furnace 10. Therefore, the warpage direction of the conveyance roller 52 is adjusted so that the difference of the conveyance speed of the heat processing part 20 of the plurality of to-be-processed objects 12a-12c arrange|positioned and arrange|positioned in the 2nd direction becomes small. The adjustment of the warpage direction of the conveyance roller 52 provided in the heat treatment unit 20 will be described in more detail below.

As described above, when the "bending" of the conveyance roller 52 is larger than the "warpage" of the conveyance roller 52, the conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52 is likely to be higher than the conveyance speed. The conveyance speed of the workpiece 12b placed on the inner side of the roller 52 is fast. As described with reference to FIG. 5, this is considered to be because the workpiece 12b placed on the inner side of the conveyance roller 52 is hardly affected by the warpage of the conveyance roller 52 and the unevenness of the diameter of the conveyance roller 52. On the other hand, the objects 12a and 12c placed on the outer side of the conveyance roller 52 are susceptible to the unevenness of the diameter of the conveyance roller 52.

When the weight of the workpiece 12 is heavy, the bending of the conveyance roller 52 near the center of the conveyance roller 52 is increased, so that the workpiece 12b placed on the inside of the conveyance roller 52 and the six conveyance rollers 52 are provided. All contact. Therefore, the workpiece 12b always has a state as shown in FIG. 5(a) regardless of the warpage direction of the conveyance roller 52. Therefore, the workpiece 12b is hardly affected by the warpage of the conveyance roller 52 and the unevenness of the diameter of the conveyance roller 52, and it is difficult to adjust the conveyance speed of the workpiece 12b. Therefore, in order to reduce the difference between the conveyance speed of the workpiece 12b placed on the inner side of the conveyance roller 52 and the conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52, it is necessary to adjust the conveyance speed. The conveyance speed of the workpieces 12a and 12c placed on the outer side of the roller 52. In other words, it is necessary to suppress the conveyance speed of the objects 12a and 12c to be fast.

Since the conveyance roller 52 has a small curvature at the end of the conveyance roller 52, the objects 12a and 12c are likely to be in a state of not contacting all of the six conveyance rollers 52. For example, as shown in FIG. 6, the conveyance roller 52 (the conveyance roller 52 shown by the virtual line in FIG. 6) which is located in the uppermost side by warpage is pressed downward by bending, but the conveyance roller 52 is bent to the upturn. The fact that the position of the conveyance roller 52 located at the bottom is curved is hardly present. Therefore, it is difficult for the workpiece 12 to come into contact with the conveyance roller 52 located at the lowest position due to warpage. However, as shown in FIG. 6(a) to FIG. 6(d), in the case where the warping direction of the adjacent conveyance rollers 52 is shifted by 90 degrees, the carrier roller 52 is rotated by 90 degrees each. In either case, the workpieces 12a and 12c are in contact with a plurality of conveyance rollers 52 (four in the example of FIG. 6 or five conveyance rollers 52) of the six conveyance rollers 52. Therefore, when the workpiece 12 comes into contact with the relatively large number of conveyance rollers 52, the influence of the unevenness of the diameter of the conveyance roller 52 becomes strong. As a result, when the warping direction of the adjacent conveyance rollers 52 is shifted by 90 degrees, the conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52 is likely to be fast.

On the other hand, as shown in FIGS. 7(a) to 7(d), when the warping direction of the adjacent conveyance rollers 52 is shifted by 180 degrees, the conveyance roller 52 is rotated by 90 degrees. One of the four types (in the case of Figs. 7(a) and 7(c)), the objects 12a and 12c are the transport rollers 52 which are relatively small among the six transport rollers 52 (in the example of Fig. 7). The three transport rollers 52) are in contact. Therefore, in FIGS. 7(a) and 7(c), the number of the conveyance rollers 52 that are in contact with the workpieces 12a and 12c becomes relatively small, and the conveyance pattern changes. According to the experiment of the present inventors, the case shown in FIG. 7 suppresses the conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52 to be faster than the case shown in FIG. The difference between the conveyance speed of the workpiece 12 placed on the inner side of the 52 and the conveyance speed of the workpiece 12 placed on the outer side of the conveyance roller 52 is small.

Moreover, when the warping directions of the adjacent conveyance rollers 52 are matched, it becomes easy to contact with all of the six conveyance rollers 52. Therefore, as in the case shown in FIG. 6, it is easy to be affected by the unevenness of the diameter of the conveyance roller 52, and the conveyance speed of the to-be-processed objects 12a and 12c which are carried in the outer side of the conveyance roller 52 becomes easy.

For the reason described above, it is considered that when the "bending" of the conveying roller 52 is larger than the "warping" of the conveying roller 52 and the amount of bending of the conveying roller 52 is large, the adjacent conveying roller 52 is disposed. When the warping direction is shifted by 180 degrees, the difference in the conveyance speed of the plurality of objects 12a to 12c arranged and placed in the second direction can be made small.

Furthermore, the adjustment of the warping direction of the conveyance roller 52 in the case where the "bending" of the conveyance roller 52 is larger than the "warpage" of the conveyance roller 52, but the weight of the workpiece 12 is relatively light is described. When the weight of the workpiece 12 is relatively light, the amount of bending of the conveyance roller 52 is small, so that the workpiece 12b disposed in the center of the conveyance roller 52 is in contact with the comparative conveyance roller 52, but the conveyance roller The objects 12a and 12c disposed at the ends of the 52 are in contact with the relatively small number of conveyance rollers 52. Therefore, the influence of the "warpage" and the "disparity in the diameter" of the workpiece 12b disposed in the center of the conveyance roller 52 is reduced, and it is difficult to adjust the conveyance speed. On the other hand, the influence of the unevenness of the diameters of the objects 12a and 12c disposed on the end side of the conveyance roller 52 is strongly exhibited. Therefore, when the warping direction of the conveyance roller 52 is not adjusted, the conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52 is processed more than the inside of the conveyance roller 52. The handling speed of the object 12b tends to be faster. Therefore, in order to reduce the difference in the conveyance speed of the workpieces 12a to 12c, it is necessary to increase the conveyance speed of the workpiece 12b.

For example, when the warpage direction of the adjacent conveyance rollers 52 is shifted by 90 degrees, when the conveyance roller 52 is located at the lowest position due to warpage, the conveyance roller 52 is in difficulty in contact with the central workpiece 12b. . In other words, in the same state as the state shown in FIG. 6, the frequency at which the turning radius of the conveying roller 52 becomes larger is higher than when the entire conveying roller 52 and the workpiece 12 are in contact with each other. Therefore, when the warpage direction of the adjacent conveyance rollers 52 is shifted by 90 degrees, the conveyance speed of the to-be-processed object 12b becomes easy. In the same manner, when the warping direction of the adjacent conveyance rollers 52 is shifted by 180 degrees, the same state as that shown in FIG. 7 is obtained. Therefore, the conveyance speed of the workpiece 12b is suppressed from being faster than the state shown in FIG.

In addition, when the warpage direction of the adjacent conveyance rollers 52 is made uniform, and the arrangement is such that the warpage direction of the adjacent conveyance rollers 52 is shifted by 180 degrees, the diameter of the conveyance roller 52 is not easily received. Since the influence of the uniformity is high, the conveyance speed of the workpiece 12b is likely to be fast. However, since the conveyance roller 52 is curved, the workpiece 12b is more likely to be in contact with the more conveyance rollers 52 than when the warpage direction of the adjacent conveyance rollers 52 is shifted by 90 degrees. Therefore, the conveyance speed of the workpiece 12b placed on the inner side of the conveyance roller 52 is set so that the warpage direction of the adjacent conveyance roller 52 is shifted by 90 degrees, respectively, and the warpage direction of the adjacent conveyance roller 52 is set. Consistent situations tend to get faster.

For the reason described above, it is considered that when the "bending" of the conveyance roller 52 is larger than the "warpage" of the conveyance roller 52, and the amount of bending of the conveyance roller 52 is small, the adjacent conveyance roller 52 is disposed. The warpage direction is shifted by 90 degrees, and the difference in conveyance speed of the plurality of objects 12a to 12c arranged and placed in the second direction can be made small.

In the present embodiment, the warpage direction of the conveyance roller 52 is adjusted in accordance with the amount of bending of the conveyance roller 52 which is generated when the workpiece 12 is placed on the conveyance roller 52. Thereby, the difference between the conveyance speed of the workpiece 12b placed on the inner side of the conveyance roller 52 and the conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52 can be made small. Therefore, when the plurality of workpieces 12 arranged and carried in the second direction in the heat treatment furnace 10 are transported to the carry-out unit 40, the variation in the conveyance direction is reduced, and the heat treatment furnace 10 can be easily carried out.

Further, in the present embodiment, when the "bending" of the conveyance roller 52 is larger than the "warpage" of the conveyance roller 52, the warping direction of the adjacent conveyance roller 52 is arranged to be shifted, but the invention is not limited thereto. Composition. The conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52 can be suppressed from being faster than the conveyance speed of the workpiece 12b placed on the inner side of the conveyance roller 52, and the plurality of conveyance rollers 52 can be used. The warping direction changes periodically. For example, the two adjacent conveying rollers 52 may be used as one unit, and the warping direction may be periodically changed. In other words, the warping directions of the two adjacent conveying rollers 52 may be the same, and the two conveying rollers 52 having the same warping direction may be shifted by 90° or 180° from the warping direction of the adjacent two conveying rollers 52. In addition, when the number of the conveyance rollers 52 for placing one workpiece 12 is large, the warping directions of the conveyance rollers 52 of three or more adjacent ones may be the same, and the warpage direction may be three or more. The conveyance roller 52 is shifted by 90 or 180 degrees from the warping direction of the adjacent three or more conveyance rollers 52.

Further, in the present embodiment, when the "bending" of the conveyance roller 52 is larger than the "warpage" of the conveyance roller 52, the warping direction of the adjacent conveyance roller 52 is shifted by 90 or 180 degrees, but not Limited to this configuration. The conveyance speed of the workpieces 12a and 12c placed on the outer side of the conveyance roller 52 can be prevented from being faster than the conveyance speed of the workpiece 12b placed on the inner side of the conveyance roller 52, and the adjacent conveyance roller 52 can be disposed. The angle in which the warpage direction is shifted is not limited to the above embodiment. For example, the warping direction of the adjacent conveying rollers 52 may be shifted by 45°, 72° or 120°, respectively.

Further, in the present embodiment, the warping direction of all the conveyance rollers 52 provided in the heat treatment portion 20 is adjusted, but the configuration is not limited thereto. The warping direction of the conveyance roller 52 may be adjusted so that the difference in the conveyance speed of the plurality of objects 12 to be placed and placed in the second direction in the heat treatment portion 20 may be small, for example, in the heat treatment portion 20 A part of the conveyance roller 52 is provided to adjust the warpage direction of the conveyance roller 52.

The specific examples of the technology disclosed in the present specification are described in detail above, but these are merely examples and are not intended to limit the scope of the patent application. The technology described in the patent application scope includes various modifications and changes to the specific examples described above. Further, the technical elements described in the patent specification or the drawings are technically useful individually or in various combinations, and are not limited to the combinations described in the claims.

10‧‧‧heat treatment furnace

12‧‧‧Processed objects

20‧‧‧ Heat Treatment Department

22‧‧‧ outer wall

24‧‧‧ Space

26‧‧‧ openings

28‧‧‧ openings

30‧‧‧heater

32‧‧‧heater

34‧‧‧ Moving into the Department

40‧‧‧ Moving out

50‧‧‧Transportation device

52‧‧‧Transport roller

60‧‧‧ drive

62‧‧‧Control device

1 is a view showing a schematic configuration of a heat treatment furnace of an 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 workpiece.

Fig. 2 is a cross-sectional view taken along line II-II of Fig. 1.

Fig. 3 is a view showing a portion where the warpage of the conveyance roller and the warpage direction are measured.

[Fig. 4] Fig. 4(a) is a view showing a state in which the warping direction of the conveyance roller is adjusted, and Fig. 4(a) shows a state in which the warping direction of the adjacent conveyance rollers is shifted by 90°, and Fig. 4(b) The state in which the warping direction of the adjacent conveyance rollers is shifted by 180 degrees is shown.

[Fig. 5] is a view for explaining conveyance of a workpiece when the bending of the conveyance roller is large, and Fig. 5(a) shows a state in which the workpiece placed on the center of the conveyance roller is placed, 5(b) shows the state in which the workpiece placed on the end of the conveyance roller is placed.

[Fig. 6] When the bending of the conveyance roller is large, the conveyance roller in a state in which the warpage direction of the adjacent conveyance roller is shifted by 90 degrees and the workpiece to be placed on the end portion of the conveyance roller are schematically indicated in the mode. 6(a) to 6(d) show a state in which the conveying rollers are rotated by 90 degrees.

[Fig. 7] When the bending of the conveyance roller is large, the conveyance roller in a state in which the warpage direction of the adjacent conveyance roller is shifted by 180 degrees and the workpiece to be placed on the end portion of the conveyance roller are shown in the mode. 7(a) to 7(d) show a state in which the conveyance rollers are rotated by 90 degrees.

Claims (6)

A heat treatment furnace is a heat treatment furnace for heat-treating a workpiece, and the system includes: The heat treatment portion includes a space for heat-treating the object to be processed; and a plurality of transport rollers are disposed in the heat treatment portion and transport the processed object; The plurality of conveyance rollers provided in the predetermined range of the heat treatment portion periodically change in the warpage direction of the portion where the warpage of the conveyance roller becomes the largest when the conveyance roller is viewed in the axial direction. The heat treatment furnace of claim 1, wherein the plurality of conveying rollers provided in a predetermined range of the heat treatment portion are constituted by a predetermined number of conveying rollers; The warping direction of each of the conveyance rollers constituting the one cycle is shifted by a predetermined angle with respect to the warpage direction of the conveyance roller adjacent to the conveyance roller. The heat treatment furnace of claim 2, further comprising a driving device capable of simultaneously driving a plurality of conveying rollers disposed in the predetermined range; The driving device maintains the warping direction of the conveying roller and the warp direction of the adjacent conveying roller shifted by the predetermined angle, and drives a plurality of conveying rollers provided in the predetermined range. A heat treatment furnace according to claim 2 or 3, wherein the predetermined angle is 90 degrees. A heat treatment furnace according to claim 2 or 3, wherein the predetermined angle is 180 degrees. A method of manufacturing a heat treatment furnace, the heat treatment furnace comprising: The heat treatment portion includes a space for heat-treating the object to be processed; and a plurality of transport rollers are disposed in the heat treatment portion and transport the processed object; The manufacturing method includes: The measurement step is a measurement of a warpage direction of a portion where the warpage of the conveyance roller becomes maximum when the conveyance roller is viewed in the axial direction with respect to each of the plurality of conveyance rollers provided in a predetermined range of the heat treatment portion; The setting step is such that the conveyance roller is set to have a measured warpage direction to periodically change the predetermined range of the heat treatment portion.