Heat treatment system

Abstract

To efficiently use a sagger body and a lid respectively.SOLUTION: A heat treatment system comprises: a heat treatment furnace that heat-treats a treatment object that is housed in a sagger including a sagger body and a lid attachable to the sagger body; a lid removing device that removes a lid from the sagger transported from the heat treatment furnace; a body transport device that transports the sagger body from which the lid is removed by the lid removing device; a lid transport device that transports the lid removed by the lid removing device; a recovery device that recovers from the sagger body the treatment object that has been heat-treated by the heat treatment furnace; a supply device disposed downstream from the recovery device and supplying to the sagger body a treatment object before heat treatment; and a lid attachment device that attaches the lid transported by the lid transport device to the sagger body transported by the body transport device. A transport time during which the lid is transported from an entrance on the side of the lid removing device to an exit on the side of the lid attachment device in a transport route of the lid transport device is set shorter than a transport time during which the sagger body is transported from the entrance on the lid removing device side to the exit on the lid attachment device side in a transport route of the body transport device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a technology for heat treating a workpiece. [Background technology]

[0002] A heat treatment furnace (for example, a roller hearth kiln or a pusher kiln) may be used to heat treat an object to be treated. For example, when a powder or other object to be treated is heat treated in a heat treatment furnace, the object is heat treated while being accommodated in a sagger. The sagger is reused and used repeatedly. For example, Patent Document 1 discloses an example of a heat treatment system including a supply device that supplies the object to be treated to the sagger, a heat treatment furnace that heat treats the object in the sagger, a recovery device that recovers the object from the sagger, and a conveying device that conveys the sagger between the supply device, the heat treatment furnace, and the recovery device. The sagger circulates in the conveying direction between the supply device, the heat treatment furnace, and the recovery device along the conveying path of the conveying device. In Patent Document 1, the sagger is loaded into the heat treatment furnace with a lid attached. On the other hand, when the object to be treated is supplied to the sagger and when the object to be treated is recovered from the sagger, the lid needs to be removed from the sagger body. The heat treatment system of Patent Document 1 includes lid removal mechanisms between the heat treatment furnace and the recovery device, and between the supply device and the heat treatment furnace, which remove lids from the sack body and attach lids to the sack body. Each of the two lid removal mechanisms includes an arm that holds the lid. The lid is removed from the sack body by gripping the lid with the arm, and only the sack body is transported to the recovery device or supply device. Then, the sack body from which the workpiece has been recovered by the recovery device or to which the workpiece has been supplied by the supply device is returned to below the arm, and the lid held by the arm is attached to the sack body. In this way, in the heat treatment system of Patent Document 1, the same lid is attached to the same sack body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7041302 Summary of the Invention [Problem to be solved by the invention]

[0004] In the heat treatment system of Patent Document 1, the combination of the sack body and the lid is fixed. However, the sack body, which is transported through the heat treatment furnace in direct contact with the workpiece, is more susceptible to deterioration than the lid attached to the top of the sack body, and the number of times it can be used is often reduced. If the same lid is attached to the same sack body and used for heat treatment many times, it may become impossible to use it in other combinations due to thermal deformation during the heat treatment. For this reason, if the combination of the sack body and the lid is fixed, when the sack body becomes unusable, the lid cannot be used with the sack body, even if it is still usable.

[0005] This specification discloses techniques for efficiently using the sagger body and the lid, respectively. [Means for solving the problem]

[0006] In a first aspect of the technology disclosed in this specification, a heat treatment system includes a heat treatment furnace, a lid removal device, a main body conveying device, a lid conveying device, a recovery device, a supply device, and a lid attachment device. The heat treatment furnace heat-treats an object to be treated housed in a sagger having a sagger body and a lid attachable to the sagger body. The heat treatment furnace includes an inlet and an outlet, and heat-treats the object to be treated housed in the sagger while conveying the sagger from the inlet to the outlet. The lid removal device removes the lid from the sagger discharged from the outlet of the heat treatment furnace. The main body conveying device conveys the sagger body from which the lid has been removed by the lid removal device. The lid conveying device conveys the lid removed by the lid removal device. The recovery device is provided on the conveying path of the main body conveying device, and recovers the object to be treated from the sagger body that has been heat-treated in the heat treatment furnace. The supply device is provided on the transport path of the main body transport device, downstream of the recovery device, and supplies the workpiece before heat treatment to a sagger body that does not contain the workpiece. The lid attachment device attaches a lid transported by the lid transport device to the sagger body that is transported by the main body transport device and to which the workpiece before heat treatment has been supplied by the supply device. The transport time for the lid to be transported from the entrance on the lid removal device side of the transport path of the lid transport device to the exit on the lid attachment device side is shorter than the transport time for the sagger body to be transported from the entrance on the lid removal device side of the transport path of the main body transport device to the exit on the lid attachment device side.

[0007] In the above heat treatment system, the lid and the sack body removed from the sack body after heat treatment are transported on different transport paths. Also, the lid transported by the lid transport device is transported in a shorter transport time than the sack body transported by the body transport device. Since the transport times of the lid and the sack body are different, the sack can be used so that the combination of the lid and the sack body is not fixed. Therefore, for example, even if the sack body becomes unusable, the lid can continue to be used. In this way, the number of times the sack body and the lid are used can be appropriately set. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a heat treatment system according to a first embodiment. [Diagram 2]FIG. 2 is a diagram showing a schematic configuration of a heat treatment furnace, and is a vertical cross-sectional view of the heat treatment furnace taken along a plane parallel to the conveying direction of the saggers. [Diagram 3] 3 is a cross-sectional view taken along line III-III in FIG. 2 . [Figure 4] FIG. 2 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] Cross-sectional view taken along line VV in Figure 1.

[0009] The main features of the embodiments described below are listed below. Note that the technical elements described below are independent technical elements that exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing.

[0010] In a second aspect of the technology disclosed in this specification, in the first aspect described above, the transport time for the sagger body to be transported from the entrance of the transport path of the body transport device on the lid removal device side to the exit of the lid installation device side may be 1.1 to 5.0 times the transport time for the lid to be transported from the entrance of the transport path of the lid transport device on the lid removal device side to the exit of the lid installation device side. With this configuration, the transport time for the lid can be suitably shortened.

[0011] In a third aspect of the technology disclosed in the present specification, in the first or second aspect described above, a lid alignment mechanism that is provided near the exit of the lid attachment device side of the transport path of the lid transport device and aligns the lids may be further provided. The lids may meander and tilt while being transported along the transport path of the lid transport device. By providing the lid alignment mechanism, the lids can be aligned at the exit of the transport path of the lid transport device on the lid attachment device side, and the lids can be sent out from the lid transport device to the lid attachment device in an untilted state.

[0012] In a fourth aspect of the technology disclosed in the present specification, in any one of the first to third aspects, the heat treatment system may further include a cleaning device that is provided in a transport path of the lid transport device and cleans the lid. With this configuration, the object to be treated adhering to the lid can be cleaned, and the lid can be suitably reused.

[0013] In a fifth aspect of the technology disclosed in the present specification, in any one of the first to fourth aspects, the heat treatment system may further include a lid inspection device that is provided in a transport path of the lid transport device and inspects the lids for defects. With this configuration, it is possible to inspect the lids for defects such as cracks, and to properly reject unreusable lids.

[0014] In a sixth aspect of the technique disclosed in the present specification, in the fifth aspect, the heat treatment system may further include a lid recovery device that is provided downstream of the lid inspection device on the transport path of the lid transport device and recovers the lids determined to be defective by the lid inspection device. With this configuration, the lids determined to be defective can be properly recovered from the transport path of the lid transport device.

[0015] In a seventh aspect of the technique disclosed in the present specification, in any one of the first to sixth aspects, the heat treatment system may further include a lid supplying device provided in the transport path of the lid transporting device and supplying lids to the transport path of the lid transporting device. With this configuration, it is possible to supply lids to the transport path of the lid transporting device. This makes it possible to avoid a shortage of lids in the lid attachment device even if the number of lids transported by the lid transporting device is reduced due to, for example, damage to the lids.

[0016] According to an eighth aspect of the technique disclosed in this specification, in the seventh aspect, the heat treatment system may further include a lid storage unit that stores the lids supplied from the lid supply device.

[0017] In a ninth aspect of the technique disclosed in the present specification, in any one of the first to seventh aspects, the heat treatment system may further include a first hood covering the transport path of the main body transport device and a second hood covering the transport path of the lid transport device. The height from the transport surface of the lid transport device to the second hood may be smaller than the height from the transport surface of the main body transport device to the first hood. The lid is for covering the upper surface of the sagger, and the dimension of the lid in the height direction is smaller than the dimension of the sagger body in the height direction. Therefore, even if the height of the second hood covering the transport path of the lid transport device that transports the lid is smaller than the height of the first hood covering the transport path of the main body transport device that transports the sagger body, the lid transport device can transport the lid appropriately. By reducing the height of the second hood covering the transport path of the lid transport device, the surface area of ​​the second hood is reduced, and the cost of manufacturing the second hood can be reduced. In addition, the weight of the second hood is reduced, and therefore the workload when attaching and detaching the second hood, for example, during maintenance, can be reduced. In addition, since the entire second hood is smaller, the removed second hood can be stored in a space-saving manner. EXAMPLES

[0018] A heat treatment system 1 according to the present embodiment will be described with reference to the drawings. As shown in Fig. 1, the heat treatment system 1 includes a heat treatment furnace 10, a circulating transport device (30, 34, 36, 38), a lid removing device 50, a treated object supply device 40, a treated object recovery device 42, a main body cleaning device 44, a main body crack detection device 46, a lid cleaning device 52, a lid crack detection device 54, a lid recovery device 56, a lid supply device 58, a lid storage 60, and a lid installation device 64.

[0019] The heat treatment system 1 heat-treats the object to be treated housed in a sagger 2 (see FIG. 2). In this embodiment, the object to be treated housed in the sagger 2 is a powder of a lithium-ion battery positive electrode material. As shown in FIGS. 2 and 3, the sagger 2 includes a body 3 and a lid 4 that can be attached to the body 3. As shown in FIG. 1, the sagger 2 is transported by a circulation transport device (30, 34, 36, 38). The sagger 2 (body 3 and lid 4) is transported through a heat treatment furnace 10, the lid 4 is removed from the body 3 by a lid removal device 50 (described in detail later), the body 3 is transported by a body transport device 34 described later, and the lid 4 is transported by a lid transport device 36 described later. That is, the body 3 and the lid 4 are transported by different transport routes in a part of the section outside the heat treatment furnace 10. Then, the main body 3 and the lid 4 join at a lid attachment device 64 (described in detail later), where the lid 4 is attached to the main body 3, and the sagger 2 (main body 3 and lid 4) is transported again through the heat treatment furnace 10. Thus, in the heat treatment system 1 of this embodiment, the sagger 2 is configured to circulate between the heat treatment furnace 10 and various devices (described in detail later). The workpiece is heat-treated while the sagger 2 is transported through the heat treatment furnace 10.

[0020] The heat treatment furnace 10 heat-treats the object to be treated in the sagger 2. As shown in Figures 2 and 3, the heat treatment furnace 10 includes a furnace body 12 and a transport device (24, 26). The heat treatment furnace 10 heat-treats the object to be treated housed in the sagger 2 while the sagger 2 is transported within the furnace body 12 by the transport device (24, 26).

[0021] The furnace body 12 has an outer shape of a substantially rectangular parallelepiped, and the heat treatment space therein is surrounded by a ceiling wall 14a, a bottom wall 14b, a furnace inlet wall 14c, a furnace outlet wall 14d, and side walls 14e and 14f. As shown in FIG. 2, the ceiling wall 14a is arranged parallel to the bottom wall 14b (i.e., parallel to the XY plane). The furnace inlet wall 14c is arranged at the inlet end of the transport path and is arranged perpendicular to the transport direction (i.e., parallel to the YZ plane). The furnace outlet wall 14d is arranged at the outlet end of the transport path and is arranged parallel to the furnace inlet wall 14c (i.e., parallel to the YZ plane). As shown in FIG. 3, the side walls 14e and 14f are arranged parallel to the transport direction and perpendicular to the ceiling wall 14a and the bottom wall 14b (i.e., parallel to the XZ plane). In the heat treatment space in the furnace body 12, a plurality of heaters 16a, 16b and a plurality of conveying rollers 24 are arranged. The heaters 16a are arranged above the conveying rollers 24 at a predetermined interval in the conveying direction, and the heaters 16b are arranged below the conveying rollers 24 at a predetermined interval in the conveying direction. When the heaters 16a, 16b generate heat, the space 18 in the furnace body 12 is heated and the object to be treated housed in the sagger 2 is heated. As shown in FIG. 2, an opening 15a is formed in the furnace inlet wall 14c, and an opening 15b is formed in the furnace outlet wall 14d. The sagger 2 is conveyed into the heat treatment furnace 10 from the opening 15a by the conveying device (24, 26) and conveyed out of the heat treatment furnace 10 from the opening 15b. That is, the opening 15a is used as an inlet, and the opening 15b is used as an outlet.

[0022] The conveying device (24, 26) includes a plurality of conveying rollers 24 and a driving device 26. The conveying rollers 24 convey the sagger 2. The conveying device (24, 26) conveys the sagger 2 into the heat treatment furnace 10 through the opening 15a, and conveys the sagger 2 out of the heat treatment furnace 10 through the opening 15b. The conveying roller 24 is cylindrical, and its axis extends in a direction perpendicular to the conveying direction (i.e., in the Y direction). All of the conveying rollers 24 have the same diameter, and are disposed at equal intervals with a constant pitch in the conveying direction. The conveying rollers 24 are supported rotatably around their axes, and rotate when a driving force of the driving device 26 is transmitted to them. The driving device 26 is a driving device (e.g., a motor) that drives the conveying rollers 24. The driving device 26 is connected to the conveying rollers 24 via a power transmission mechanism. When the driving force of the drive unit 26 is transmitted to the transport rollers 24 via a power transmission mechanism (e.g., a mechanism using a sprocket and a chain), the transport rollers 24 rotate. The drive unit 26 drives each of the transport rollers 24 so that the transport rollers 24 rotate at approximately the same speed. The drive unit 26 is controlled by a control unit 28. In this embodiment, the multiple transport rollers 24 all have the same diameter, but this is not limited to the configuration. Transport rollers of different diameters may be installed inside the heat treatment furnace 10.

[0023] As shown in FIG. 1, the circulating conveying device (30, 34, 36, 38) conveys the saggers 2 discharged from the discharge outlet (i.e., opening 15b) of the heat treatment furnace 10 to the discharge inlet (i.e., opening 15a) of the heat treatment furnace 10. The circulating conveying device (30, 34, 36, 38) includes a plurality of conveying rollers 32 (see FIGS. 4 and 5) and a driving device (not shown). The conveying rollers 32 are cylindrical, and their axes extend in a direction perpendicular to the conveying direction. All of the conveying rollers 32 have the same diameter and are disposed at equal intervals with a constant pitch in the conveying direction. The conveying rollers 32 are supported rotatably around their axes, and rotate when a driving force from a driving device is transmitted to them. The driving device is a driving device (e.g., a motor) that drives the conveying rollers 32. The driving device is connected to the conveying rollers 32 via a power transmission mechanism. When the driving force of the drive device is transmitted to the transport rollers 32 via a power transmission mechanism (e.g., a mechanism using a sprocket and a chain), the transport rollers 32 rotate. The drive device drives each of the transport rollers 32 so that the transport rollers 32 rotate at approximately the same speed. In this embodiment, all of the multiple transport rollers 32 have the same diameter, but this is not limited to the above configuration. Transport rollers of different diameters may be installed on the transport path of the circulating transport device (30, 34, 36, 38).

[0024] The circulating conveying device (30, 34, 36, 38) includes an unloading conveying device 30, a main body conveying device 34, a lid conveying device 36, and an inlet conveying device 38. The unloading conveying device 30 conveys the sagger 2 unloaded from the discharge outlet (i.e., opening 15b) of the heat treatment furnace 10 to the lid removing device 50. The main body conveying device 34 conveys the main body 3 from which the lid 4 has been removed by the lid removing device 50 (described in detail later) to the lid attaching device 64. The lid conveying device 36 conveys the lid 4 removed from the main body 3 by the lid removing device 50 to the lid attaching device 64. The inlet conveying device 38 conveys the sagger 2 from which the lid 4 has been attached to the main body 3 by the lid attaching device 64 (described in detail later) to the discharge inlet (i.e., opening 15a) of the heat treatment furnace 10. In this embodiment, when the lid 4 is removed from the main body 3 by the lid removal device 50, the main body 3 is transported by the main body conveying device 34, the lid 4 is transported by the lid conveying device 36, and the main body 3 and the lid 4 join at the lid attachment device 64. That is, for the sagger 2 composed of the main body 3 and the lid 4, the main body 3 and the lid 4 are transported on different transport paths in a portion of the outside of the heat treatment furnace 10. Also, in this embodiment, the transport time taken for the lid 4 to be transported on the transport path of the lid conveying device 36 is shorter than the transport time taken for the main body 3 to be transported on the transport path of the main body conveying device 34. The main body conveying device 34 and the lid conveying device 36 will be described in detail later.

[0025] The lid removing device 50 is disposed downstream of the discharge port of the heat treatment furnace 10. The lid removing device 50 is a device that removes the lid 4 from the body 3 of the sagger 2 (specifically, the sagger 2 with the lid 4 attached to the body 3) that is discharged from the discharge port of the heat treatment furnace 10. The lid removing device 50 is not particularly limited in its specific configuration as long as it is configured to remove the lid 4 from the body 3 of the sagger 2. For example, the lid removing device 50 includes a gripping part that grips the lid 4, and is configured so that the gripping part can be raised and lowered relative to the body 3. The gripping part that grips the lid 4 is raised relative to the body 3, thereby removing the lid 4 from the body 3. When the lid 4 is removed, the body 3 is sent to the conveying path of the body conveying device 34. The lid 4 removed from the body 3 is sent to the conveying path of the lid conveying device 36.

[0026] On the transport path of the main body transport device 34, there are arranged a processed material recovery device 42, a main body cleaning device 44, a main body crack detection device 46, and a processed material supply device 40. When the main body 3 is transported out of the lid removal device 50, it is transported by the main body transport device 34 to the processed material recovery device 42, the main body cleaning device 44, the main body crack detection device 46, and the processed material supply device 40.

[0027] The object recovery device 42 is disposed on the transport path of the main body transport device 34. The object recovery device 42 is disposed between the lid removal device 50 and the main body cleaning device 44. The object recovery device 42 is a device that recovers the object (i.e., powder) that has been heat-treated in the heat treatment furnace 10 from the main body 3. The object recovery device 42 is only required to be configured to recover the powder from the main body 3, and the specific structure is not particularly limited. For example, the object recovery device 42 includes an inversion recovery section that recovers the object by inverting the main body 3 in the vertical direction, and an air recovery section that peels off the object (powder in this embodiment) attached to the surface of the main body 3 with air and recovers it. The inversion recovery section moves the powder in the main body 3 to a recovery container by inverting the main body 3 in the vertical direction. As a result, almost all of the powder contained in the main body 3 moves to the recovery container. After that, the inversion recovery section inverts the main body 3 again in the vertical direction to return it to its original orientation. The air recovery section is used after the powder in the main body 3 is recovered by the inversion recovery section. The air collection unit sucks the air inside the main body 3 while blowing air onto the inner surface of the main body 3. By blowing air onto the inner surface of the main body 3, the powder adhering to the inner surface of the main body 3 is peeled off from the inner surface. When the air inside the main body 3 is sucked while blowing air onto the inner surface of the main body 3, the powder peeled off from the inner surface of the main body 3 is sucked together with the air. This allows the powder remaining on the inner surface of the main body 3 to be collected, and the powder collection rate increases. In the above example, the object collection device 42 includes an air collection unit, but is not limited to such a configuration. For example, the powder remaining on the inner surface of the main body 3 may be configured to be peeled off from the inner surface of the main body 3 by a rotating brush and collected.

[0028] The main body cleaning device 44 is disposed on the conveying path of the main body conveying device 34. The main body cleaning device 44 is disposed between the treated object recovery device 42 and the main body crack detection device 46. The main body cleaning device 44 is a device that cleans the inner surface of the main body 3 after the treated object (i.e., powder) is recovered in the treated object recovery device 42. The main body cleaning device 44 is not particularly limited in its specific structure as long as it is configured to clean the inner surface of the main body 3. For example, the main body cleaning device 44 sucks air and the like in the main body 3 while peeling off substances adhering to the inner surface of the main body 3 using a rotating brush. The sucked air and the like contain the peeled off substances. By cleaning the inner surface of the main body 3 with the main body cleaning device 44, the powder and the like remaining on the inner surface of the main body 3 can be completely removed.

[0029] The body crack detection device 46 is disposed on the conveying path of the body conveying device 34. The body crack detection device 46 is disposed between the body cleaning device 44 and the treated object supplying device 40. The body crack detection device 46 is a device for detecting cracks in the body 3 to inspect whether the body 3 is cracked or not. The sagger 2 is repeatedly used for the heat treatment of the treated object in the heat treatment furnace 10. The body crack detection device 46 inspects whether the body 3 is cracked or not before being reused after being used for the heat treatment of the treated object in the heat treatment furnace 10. Note that the body crack detection device 46 only needs to be configured to detect cracks in the body 3, and the specific configuration is not particularly limited. For example, the body crack detection device 46 may detect cracks in the body 3 using a laser. Also, the body crack detection device 46 may detect cracks in the body 3 by sealing gas in the body 3 and measuring the pressure inside the body 3. When a crack in the body 3 is detected, the body 3 is taken out from the conveying path of the body conveying device 34. That is, the main body crack detection device 46 also functions as a recovery device that recovers the main body 3 from the heat treatment system 1. If no crack is detected in the main body 3, the main body 3 is transported to the workpiece supply device 40 by the main body transport device 34. In this embodiment, the main body crack detection device 46 also functions as a recovery device for the main body 3, but a recovery device that recovers the main body 3 from the heat treatment system 1 may be installed downstream of the main body crack detection device 46.

[0030] The workpiece supply device 40 is disposed on the transport path of the main body transport device 34. The workpiece supply device 40 is disposed between the main body crack detection device 46 and the lid mounting device 64. The workpiece supply device 40 is a device that supplies the workpiece (i.e., powder) into the main body 3. The workpiece supply device 40 may be configured to supply powder into the main body 3, and the specific structure is not particularly limited. For example, the workpiece supply device 40 includes a supply unit and a leveling unit. The supply unit is configured to supply powder into the inside of the main body 3. Specifically, the supply unit includes a supply port that drops powder into the inside of the main body 3 from above the main body 3. The supply port is disposed so as to be located above the center of the main body 3 when the main body 3 is disposed in the supply unit. The supply unit includes a positioning device, and the positioning device positions the main body 3 transported to the supply unit so as to be located below the supply port. The supply unit may include multiple supply ports. The supply unit supplies powder into the main body 3 by dropping the powder from above, so when powder is supplied to the main body 3 by the supply unit, the upper surface of the powder in the main body 3 becomes raised at a position below the supply port. The leveling unit levels out the powder supplied into the main body 3 by the supply unit. Specifically, the leveling unit is configured to level out the upper surface of the powder by pressing the upper surface of the powder in the main body 3 with the side of a flat plate. By leveling the upper surface of the powder with the leveling unit, the upper surface of the powder contained in the main body 3 becomes approximately horizontal.

[0031] A lid cleaning device 52, a lid crack detection device 54, a lid recovery device 56, and a lid supply device 58 are arranged on the transport path of the lid transport device 36. When the lid 4 is transported from the lid removal device 50, it is transported by the lid transport device 36 to the lid cleaning device 52, the lid crack detection device 54, the lid recovery device 56, and the lid supply device 58.

[0032] The lid cleaning device 52 is disposed on the conveying path of the lid conveying device 36. The lid cleaning device 52 is disposed between the lid removing device 50 and the lid crack detection device 54. When the lid 4 is attached to the main body 3, the treated object (i.e., powder) contained in the main body 3 may adhere to the surface of the main body 3. The lid cleaning device 52 is a device for cleaning the treated object adhered to the lid 4. The lid cleaning device 52 is not particularly limited in its specific structure as long as it is configured to clean the lid 4. For example, the lid cleaning device 52 can have substantially the same configuration as the main body cleaning device 44 described above. By cleaning the lid 4 with the lid cleaning device 52, the powder remaining on the surface of the lid 4 can be completely removed.

[0033] The lid crack detection device 54 is disposed on the conveying path of the lid conveying device 36. The lid crack detection device 54 is disposed between the lid cleaning device 52 and the lid recovery device 56. The lid crack detection device 54 is a device for detecting the cracks in the lid 4 to inspect whether the lid 4 is cracked or not. As described above, the sagger 2 is repeatedly used in the heat treatment of the workpiece in the heat treatment furnace 10. The lid crack detection device 54 inspects whether the lid 4 is cracked or not before it is reused after it has been used in the heat treatment of the workpiece in the heat treatment furnace 10. Note that the lid crack detection device 54 only needs to be configured to detect the cracks in the lid 4, and there is no particular limitation on the specific configuration. For example, the lid crack detection device 54 can have substantially the same configuration as the main body crack detection device 46 described above.

[0034] The lid recovery device 56 is disposed on the conveying path of the lid conveying device 36. The lid recovery device 56 is disposed downstream of the lid crack detection device 54, and in this embodiment, it is disposed between the lid crack detection device 54 and the lid supply device 58. The lid recovery device 56 recovers the lids 4 whose cracks have been detected by the lid crack detection device 54. That is, the lids 4 whose cracks have been detected by the lid crack detection device 54 are not conveyed downstream from the lid recovery device 56 (specifically, to the lid supply device 58). By recovering the lids 4 whose cracks have been detected by the lid crack detection device 54 with the lid recovery device 56, it is possible to avoid the reuse of defective lids 4. The lids 4 whose cracks have not been detected by the lid crack detection device 54 are conveyed to the lid supply device 58 through the lid recovery device 56.

[0035] The lid supplying device 58 is disposed on the transport path of the lid transporting device 36. The lid supplying device 58 is disposed between the lid collecting device 56 and the lid attaching device 64. The lid supplying device 58 supplies new lids 4 onto the transport path of the lid transporting device 36. Specifically, when the lid collecting device 56 collects the lids 4, the lid supplying device 58 supplies new lids 4 (i.e., lids 4 other than the lids 4 circulating on the transport path in the heat treatment system 1) to the transport path of the lid transporting device 36. When the lid collecting device 56 collects the lids 4, the number of lids 4 circulating on the transport path in the heat treatment system 1 decreases. By supplying the lids 4 with the lid supplying device 58, the lids 4 can be automatically supplied, and a shortage of lids 4 to be attached to the main body 3 can be avoided.

[0036] In addition, a lid storage 60 for storing lids 4 is disposed near the lid supplying device 58. The lid storage 60 is disposed at a position different from the transport path of the lid conveying device 36, and is disposed at a position where lids 4 can be replenished to the lid supplying device 58. In this embodiment, the lid storage 60 is connected to the transport path of the lid conveying device 36, and is configured to replenish lids 4 to the lid supplying device 58 via a portion of the transport path of the lid conveying device 36. By disposing the lid storage 60, it is possible to prevent a shortage of lids 4 supplied from the lid supplying device 58.

[0037] The lid mounting device 64 is disposed upstream of the entrance of the heat treatment furnace 10. In the lid mounting device 64, the transport path of the main body transport device 34 and the transport path of the lid transport device 36 join together. That is, the main body 3 transported by the main body transport device 34 (specifically, the main body 3 to which the workpiece is supplied by the workpiece supply device 40) is transported to the lid mounting device 64, and the lid 4 transported by the lid transport device 36 (specifically, the lid 4 that has passed through the lid supply device 58 or the lid 4 that has been supplied onto the transport path from the lid supply device 58) is transported to the lid mounting device 64. The lid mounting device 64 is a device that attaches the lid 4 transported by the lid transport device 36 to the main body 3 transported by the main body transport device 34. Note that the lid mounting device 64 is not particularly limited in its specific configuration, as long as it is configured to attach the lid 4 to the main body 3. For example, the lid mounting device 64 includes a gripping portion that grips the lid 4, and the gripping portion is configured to be movable in the XYZ directions relative to the main body 3. The lid 4 held by the gripping portion is moved above the main body 3 and attached to the main body 3. Before being carried into the lid attachment device 64, the main body 3 is supplied with an object to be treated by the object supply device 40. In the lid attachment device 64, the lid 4 is attached to the main body 3 containing the object to be treated.

[0038] In addition, a lid alignment mechanism 62 for aligning the lids 4 is installed near the exit of the lid attachment device 64 side of the conveying path of the lid conveying device 36. As shown in Figures 2 and 3, in this embodiment, the sagger 2 is rectangular when viewed from above, and the lids 4 are also rectangular when viewed from above. The lids 4 may tilt while being conveyed along the conveying path of the lid conveying device 36. If the lids 4 are tilted, the lid attachment device 64 may not be able to grip the lids 4. The lid alignment mechanism 62 aligns the front surface of the lids 4 in the conveying direction so that it is perpendicular to the conveying direction. The lid alignment mechanism 62 can be configured, for example, by a flat stopper. The stopper of the lid alignment mechanism 62 is installed so that it is perpendicular to the conveying direction and can move in the vertical direction. When the stopper of the lid alignment mechanism 62 moves upward, the front surface of the lids 4 abuts against the stopper of the lid alignment mechanism 62, and the front surface of the lids 4 is aligned in a direction perpendicular to the conveying direction. When the stopper of the lid alignment mechanism 62 is moved downward, the lid 4 can pass above the lid alignment mechanism 62. By installing the lid alignment mechanism 62, the lid 4 can be more securely gripped by the lid attachment device 64, and the lid 4 can be properly attached to the body 3. Once the lid 4 is attached to the body 3, the sagger 2 (i.e., the sagger 2 with the lid 4 attached to the body 3) is carried into the heat treatment furnace 10 by the carry-in transport device 38.

[0039] Here, the main body conveying device 34 and the lid conveying device 36 will be described in more detail. In this embodiment, the conveying time required for the lid 4 to be conveyed along the conveying path of the lid conveying device 36 is shorter than the conveying time required for the main body 3 to be conveyed along the conveying path of the main body conveying device 34. That is, the conveying path of the main body conveying device 34 (i.e., between the main body 3 and the lid removing device 50 and the lid mounting device 64) is provided with the treated object recovery device 42, the main body cleaning device 44, the main body crack detection device 46, and the treated object supply device 40. When the main body 3 is conveyed through each of the devices 42, 44, 46, and 40, a work time is generated for each of them. On the other hand, the conveying path of the lid conveying device 36 (i.e., between the lid 4 and the lid removing device 50 and the lid mounting device 64) is provided with the lid cleaning device 52, the lid crack detection device 54, the lid recovery device 56, and the lid supply device 58. When the lid 4 is conveyed through the lid cleaning device 52 and the lid crack detection device 54, a work time is generated for each of them. However, the reused lids 4 (lids 4 whose cracks were not detected by the lid crack detection device 54) only pass through the lid recovery device 56 and the lid supply device 58, and no work time is generated when the lids 4 pass through the lid recovery device 56 and the lid supply device 58. In addition, since the lids 4 have a smaller volume than the main body 3, their surface area is also small, and the work time required by the lid cleaning device 52 and the lid crack detection device 54 is shorter than the work time required by the main body cleaning device 44 and the main body crack detection device 46. For this reason, the transport time required for the lids 4 to be transported along the transport path of the lid transport device 36 (hereinafter, also simply referred to as the transport time of the lids 4) can be shorter than the transport time required for the main body 3 to be transported along the transport path of the main body transport device 34 (hereinafter, also simply referred to as the transport time of the main body 3). Specifically, the transport time of the main body 3 is 1.1 to 5.0 times the transport time of the lids 4.

[0040] Since the transport time of the lids 4 is shorter than the transport time of the main bodies 3, the number of lids 4 can be made smaller than the number of the main bodies 3. In this embodiment, the total number of lids 4 used simultaneously in the heat treatment system 1 is made smaller than the total number of the main bodies 3. Looking at the heat treatment system 1 at a certain point in time, the total number of lids 4 and the total number of the main bodies 3 are the same in the heat treatment furnace 10, the carry-out conveying device 30, and the carry-in conveying device 38. Therefore, the total number of lids 4 transported by the lid conveying device 36 is smaller than the total number of the main bodies 3 transported by the main body conveying device 34. By adjusting the transport time of the sack 2 (i.e., the main body 3 and the lids 4) transported between the heat treatment furnace 10, the carry-out conveying device 30, and the carry-in conveying device 38, the transport time of the main body 3, and the transport time of the lids 4, the number of lids 4 can be made smaller than the number of the main bodies 3 while efficiently performing the heat treatment of the object to be treated in the heat treatment furnace. By making the number of lids 4 smaller than the number of the main bodies 3, the cost of the lids 4 can be reduced. In addition, because the transport time of the lid 4 is shorter than the transport time of the main body 3 and the number of lids 4 can be less than the number of main bodies 3, the lid 4 and the main body 3 are not used in the same combination every time. If the lid 4 and the main body 3 are used in the same combination continuously, the lid 4 and the main body 3 may be thermally deformed during heat treatment, and the lid 4 and the main body 3 may not be used in a different combination. If the combination of the lid 4 and the main body 3 is fixed in this way, when one of the lid 4 and the main body 3 becomes unnecessary, the other cannot be reused. In this embodiment, since the combination of the lid 4 and the main body 3 is not fixed, even if one of the lid 4 and the main body 3 becomes unnecessary, the other can be reused. In particular, since the main body 3 comes into direct contact with the object to be treated during heat treatment, the number of times that it can be reused is often fewer than that of the lid 4. In this embodiment, the main body 3 and the lid 4 can be reused an appropriate number of times. In addition, since the transport time of the lid 4 can be shortened, the time from when the lid 4 is taken out of the heat treatment furnace 10 to when it is taken back into the heat treatment furnace 10 can be shortened compared to the main body 3. Therefore, the lid 4 can be loaded into the heat treatment furnace 10 again before it is completely cooled, thereby reducing the energy required to raise the temperature of the lid 4. As is clear from the above, the lid 4 and the body 3 are not used in the same combination every time, but if the lid 4 and the body 3 are used repeatedly, the lid 4 and the body 3 may accidentally come into the same combination.However, by adjusting the number of bodies 3 relative to the number of lids 4, it is possible to reduce the frequency with which the lids 4 and the bodies 3 accidentally come together in the same combination. Therefore, even if the lids 4 and the bodies 3 accidentally come together in the same combination, this does not pose a problem.

[0041] In this embodiment, the conveying speed (driving force by a drive device, not shown) at which the main body 3 is conveyed by the main body conveying device 34 is the same as the conveying speed (driving force by a drive device, not shown) at which the lid 4 is conveyed by the lid conveying device 36, but is not limited to this configuration. For example, the conveying speed at which the lid 4 is conveyed by the lid conveying device 36 may be faster than the conveying speed at which the main body 3 is conveyed by the main body conveying device 34.

[0042] As shown in FIG. 4, the conveying path of the main body conveying device 34 is covered with a hood 70, and as shown in FIG. 5, the conveying path of the lid conveying device 36 is covered with a hood 72. By covering the conveying path of the main body conveying device 34 with the hood 70, it is possible to prevent external foreign objects from adhering to the main body 3 conveyed by the main body conveying device 34. Similarly, by covering the conveying path of the lid conveying device 36 with the hood 72, it is possible to prevent external foreign objects from adhering to the lid 4 conveyed by the lid conveying device 36. Although not shown in the figure, the conveying path of the unloading conveying device 30 and the conveying path of the loading conveying device 38 are also covered with hoods. Therefore, it is possible to prevent external foreign objects from adhering to the sagger 2 conveyed by the unloading conveying device 30 and the loading conveying device 38.

[0043] Also, the height dimension of the lid 4 is smaller than the height dimension of the main body 3 (see Figs. 2 and 3). Therefore, as shown in Figs. 4 and 5, the height T2 from the conveying surface of the lid conveying device 36 to the hood 72 can be smaller than the height T1 from the conveying surface of the main body conveying device 34 to the hood 70. By making the height T2 smaller than the height T1, the height dimension of the hood 72 covering the conveying path of the lid conveying device 36 can be reduced, the surface area of ​​the hood 72 can be reduced, and the cost of the hood 72 can be reduced. In addition, by making the hood 72 smaller, the weight of the hood 72 can also be reduced. Therefore, for example, when the worker removes the hood 72 during maintenance, the burden on the worker can be reduced. In addition, by making the hood 72 smaller, the storage space for storing, for example, spare hoods 72 can be saved.

[0044] Points to note regarding the heat treatment system 1 described in the embodiment will be described below. The main body 3 in the embodiment is an example of a "sagger main body", the treated material supply device 40 is an example of a "supply device", the treated material recovery device 42 is an example of a "recovery device", the lid cleaning device 52 is an example of a "cleaning device", the lid crack detection device 54 is an example of a "lid inspection device", the hood 70 is an example of a "first hood", and the hood 72 is an example of a "second hood".

[0045] Although specific examples of the technology disclosed in this specification have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. Furthermore, the technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings achieves multiple objectives simultaneously, and achieving one of the objectives itself has technical utility. [Explanation of symbols]

[0046] 1: Heat treatment system 2: Box 10: Heat treatment furnace 30: Unloading and transporting device 32: Transport roller 34: Main body transport device 36: Lid conveying device 38: Loading and transporting equipment 40: Processing object supply device 42: Processing object recovery device 44: Main body cleaning device 46: Body crack detection device 50: Lid removal device 52: Lid cleaning device 54: Lid crack detection device 56: Lid recovery device 58: Lid supply device 60: Lid storage 62: Lid alignment device 64: Lid mounting device

Claims

1. a heat treatment furnace for heat-treating an object to be treated housed in a sagger having a sagger body and a lid attachable to the sagger body, the heat treatment furnace having an inlet and an outlet, the heat treatment being performed on the object to be treated housed in the sagger while the sagger is being transported from the inlet to the outlet; a lid removing device that removes the lid from the sagger that is discharged from the discharge port of the heat treatment furnace; a body conveying device that conveys the sagger body from which the lid has been removed by the lid removing device; a lid conveying device that conveys the lid removed by the lid removing device; a recovery device that is provided on a transport path of the main body transport device and recovers the workpiece that has been heat-treated in the heat treatment furnace from the sagger main body; a supply device that is provided downstream of the recovery device on the conveying path of the main body conveying device and that supplies the workpiece before heat treatment to the sagger main body in which the workpiece is not accommodated; a lid attachment device that attaches the lid, which is transported by the lid transport device, to the sagger body that is transported by the body transport device and to which the workpiece before heat treatment is supplied by the supply device; Equipped with A heat treatment system in which the transport time for the lid to be transported from the entrance on the lid removal device side of the transport path of the lid transporting device to the exit on the lid attachment device side is shorter than the transport time for the sagger body to be transported from the entrance on the lid removal device side of the transport path of the body transporting device to the exit on the lid attachment device side.

2. The heat treatment system of claim 1, wherein the transport time for the sagger body to be transported from the entrance on the lid removal device side of the transport path of the body transport device to the exit on the lid attachment device side is 1.1 to 5.0 times the transport time for the lid to be transported from the entrance on the lid removal device side of the transport path of the lid transport device to the exit on the lid attachment device side.

3. The heat treatment system according to claim 1 , further comprising a lid alignment mechanism provided near an exit of the transfer path of the lid transfer device on the lid attachment device side, for aligning the lids.

4. The heat treatment system according to claim 1 , further comprising a cleaning device provided on a transport path of the lid transport device for cleaning the lid.

5. The heat treatment system according to claim 1 , further comprising a lid inspection device provided on a transport path of the lid transport device and configured to inspect the lids for defects.

6. The heat treatment system according to claim 5 , further comprising a lid recovery device provided on a transport path of the lid transport device downstream of the lid inspection device, which recovers lids determined to be defective by the lid inspection device.

7. The heat treatment system according to claim 6 , further comprising a lid supplying device provided in a transfer path of the lid transporting device and supplying lids to the transfer path of the lid transporting device.

8. The heat treatment system according to claim 7 , further comprising a lid storage section that stores the lids supplied from the lid supply device.

9. A first hood that covers a conveying path of the main body conveying device; A second hood that covers the conveying path of the lid conveying device, A heat treatment system according to any one of claims 1 to 8, wherein the height from the transport surface of the lid transport device to the second hood is smaller than the height from the transport surface of the main body transport device to the first hood.

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