Heat Treatment System

Abstract

To superimpose saggers in a desired order when superimposing them in a vertical direction.SOLUTION: A heat treatment system comprises a heat treatment furnace, a supply device, a stacking device, a first conveying device, a destacking device, a collection device, and a second conveying device. The heat treatment furnace performs heat treatment of treatment targets housed in saggers stacked in the vertical direction. The supply device supplies the saggers with the treatment targets. The stacking device stacks a plurality of saggers. The first conveying device conveys the stacked saggers to a carry-in port of the heat treatment furnace. The destacking device destacks the plurality of stacked saggers. The collection device collects from the saggers the treatment targets. The second conveying device conveys the saggers conveyed out from a carry-out port of the heat treatment furnace to the destacking device. At least the collection device and the supply device are provided at least with a first conveying mechanism conveying the saggers along a first conveying route and a second conveying mechanism conveying the saggers along a second conveying route. Each of the first conveying route and the second conveying route is provided with a recovery portion or a supply portion.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 (e.g., a roller hearth kiln, a pusher kiln, etc.) may be used to heat treat an object to be treated. For example, when an object to be treated, such as a powder, is heat treated in a heat treatment furnace, the object is heat treated while contained 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, and a recovery device that recovers the object from the sagger. The sagger is transported between the supply device, the heat treatment furnace, and the recovery device, and is used repeatedly for heat treating the object to be treated in the heat treatment furnace.

[0003] When heat treatment is performed in a heat treatment furnace, a plurality of saggers containing the objects to be treated are sometimes stacked vertically in order to improve productivity. On the other hand, when the objects to be treated are supplied into the saggers or when the objects to be treated are recovered from the saggers, the saggers are not stacked. For this reason, the saggers that are stacked and transported in the heat treatment furnace are unstacked after being taken out of the heat treatment furnace, and the objects to be treated are recovered from each sagger by a recovery device. Then, the objects to be treated are supplied again into the saggers by the supply device, and the saggers are stacked again and transported into the heat treatment furnace. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7041300 Summary of the Invention [Problem to be solved by the invention]

[0005] In the heat treatment system of Patent Document 1, the saggers are transported between a supply device, a heat treatment furnace, and a recovery device. When the objects to be treated are stacked and heat treated in such a heat treatment system, generally, the stacking and unstacking are performed using a transport mechanism for transporting the saggers (e.g., a transport mechanism using transport rollers, etc.). That is, when stacking, the lower sagger is transported first while the upper sagger is being held, and then the held sagger is placed on the transport mechanism. Therefore, the sagger placed at the bottom is transported first, and the saggers stacked on top are transported next. Next, the objects to be treated in the saggers are collected in the recovery device, and the untreated objects to be treated are supplied to the saggers in the supply device, after which the saggers are stacked. When stacking, the sack that is being transported first is lifted and held while the next sack is transported, and when the next sack is below the held sack, the held sack is stacked on top of the next sack. Therefore, the sack that is being transported first is stacked on top, and the sack that is being transported later is located below. In this way, the order of the sacks is reversed before and after stacking.

[0006] However, there are cases where a user wants to arrange the stacked saggers in a desired order. For example, when a heat treatment is performed with a lid on the top of the saggers, only the topmost sagger among the stacked saggers has a lid on its top. For this reason, when the saggers are used for heat treatment multiple times, the shape of the topmost sagger and the saggers placed below may differ due to thermal deformation. In such a case, it is necessary to always stack a sagger having a shape for placing a lid on it at the top. In the conventional heat treatment system, the top-down order of the saggers is reversed before and after stacking, so that the sagger to place a lid on cannot always be stacked at the top. Thus, in the conventional heat treatment system, there is a problem that the top-down order of the stacked saggers cannot be arranged in a desired order.

[0007] This specification discloses a technique that allows saggers to be stacked in a desired order when stacked vertically. [Means for solving the problem]

[0008] In a first aspect of the technology disclosed in this specification, the heat treatment system includes a heat treatment furnace, a supply device, a stacking device, a first transport device, a de-stack device, a recovery device, and a second transport device. The heat treatment furnace includes an entrance and an exit, and heat-treats the objects to be treated contained in the vertically stacked saggers while transporting the saggers from the entrance to the exit. The supply device supplies the objects to be treated before heat treatment to the saggers that do not contain the objects to be treated. The stacking device vertically stacks the multiple saggers to which the objects to be treated are supplied by the supply device. The first transport device transports the saggers stacked vertically by the stacking device to the entrance of the heat treatment furnace. The de-stack device de-stacks the multiple saggers stacked vertically and discharged from the exit of the heat treatment furnace. The recovery device recovers the objects to be treated that have been heat-treated in the heat treatment furnace from the saggers de-stacked by the de-stack device. The second conveying device conveys the saggers discharged from the discharge port of the heat treatment furnace to the de-stack device. At least one of the recovery device and the supply device includes at least a first conveying mechanism that conveys the saggers along a first conveying path, and a second conveying mechanism that conveys the saggers along a second conveying path different from the first conveying path. Each of the first conveying path and the second conveying path is provided with a recovery section that recovers the material to be treated in the saggers, or a supply section that supplies the material to be treated into the saggers.

[0009] In the above heat treatment system, at least one of the recovery device and the supply device is provided with a first transport path and a second transport path, so that the recovery device and / or the supply device transports the saggers in parallel. This allows the saggers to be stacked again after the heat-treated objects are recovered from the saggers in a stacked manner, without the vertical order of the saggers being fixed, and they can be stacked in a desired order. [Brief description of the drawings]

[0010] [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 block diagram showing a control system of the heat treatment system according to the first embodiment. [Diagram 3]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. [Figure 4] 4 is a cross-sectional view taken along line IV-IV in FIG. 3 . [Diagram 5] FIG. 13 is a side view for explaining the operation of stacking sacks by the stacking device. [Figure 6] FIG. 13 is a side view for explaining the operation of de-stacking stacked sacks using a de-stack device. [Figure 7] FIG. 2 is a block diagram showing a control system of the recovery device according to the first embodiment. [Figure 8] FIG. 4 is a diagram showing a first transport path and a second transport path. [Figure 9] FIG. 13 is a diagram showing a schematic configuration of a heat treatment system according to a second embodiment. [Figure 10] FIG. 13 is a diagram showing a schematic configuration of a heat treatment system according to a third embodiment.

[0011] 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.

[0012] In a second aspect of the technology disclosed in the present specification, the above-mentioned first aspect may further include a branching section provided upstream of the first and second transport paths, which branches the saggers to either the first or second transport path, and a junction section provided downstream of the first and second transport paths, which junctions the saggers transported on the first and second transport paths. With this configuration, the transport paths can be made in series for the entire transport path except for the portion between the branching section and the junction section. Therefore, the area in parallel can be kept to a minimum, and the equipment cost of the entire heat treatment system can be reduced.

[0013] In a third aspect of the technology disclosed in the present specification, in the second aspect described above, at least one of the first and second transport paths may further be provided with an adjustment mechanism for adjusting the order in which the saggers transported on the first and second transport paths are brought into the junction. With this configuration, the order in which the saggers are brought into the junction can be suitably adjusted, and the saggers can be stacked in a desired order. EXAMPLES

[0014] Example 1 A heat treatment system 100 according to this embodiment will be described with reference to the drawings. As shown in Fig. 1 and Fig. 2, the heat treatment system 100 includes a heat treatment furnace 10, a circulating transport device 30, a supply device 40, a stacking device 50, a de-stacking device 54, a recovery device 60, a cleaning device 44, a crack detection device 46, and a management device 48.

[0015] The heat treatment system 100 heat-treats the object to be treated housed in the sagger 2 (see FIG. 3). In this embodiment, the object to be treated housed in the sagger 2 is a powder of a positive electrode material for a lithium ion battery. In the heat treatment system 100 of this embodiment, the sagger 2 is configured to circulate among the supply device 40, the stacking device 50, the heat treatment furnace 10, the disassembly device 54, the recovery device 60, the cleaning device 44, and the crack detection device 46. The object to be treated is heat-treated while the sagger 2 is transported in the heat treatment furnace 10. As shown in FIG. 2, the management device 48 is connected to the heat treatment furnace 10, the circulation transport device 30, the supply device 40, the stacking device 50, the disassembly device 54, the recovery device 60, the cleaning device 44, and the crack detection device 46. The management device 48 controls the operations of the heat treatment furnace 10, the circulating transport device 30, the supply device 40, the stacking device 50, the de-stacking device 54, the recovery device 60, the cleaning device 44, and the crack detection device 46.

[0016] The heat treatment furnace 10 heat-treats the object to be treated in the sagger 2. As shown in Figures 3 and 4, 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 contained in the sagger 2 while the sagger 2 is transported inside the furnace body 12 by the transport device (24, 26). In the heat treatment furnace 10 of this embodiment, multiple saggers 2 can be transported in a state where they are stacked vertically (i.e., multiple saggers 2 are stacked in layers).

[0017] 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. 3, 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. 4, 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. 3, 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.

[0018] 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 placed on the conveying rollers 24. 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 rollers 24 are cylindrical, and their axes extend 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 driving device 26 is transmitted to the transport rollers 24 via a power transmission mechanism (for example, a mechanism using a sprocket and a chain), the transport rollers 24 rotate. The driving device 26 drives each of the transport rollers 24 so that the transport rollers 24 rotate at approximately the same speed. The driving device 26 is controlled by the control device 28. In this embodiment, the multiple transport rollers 24 all have the same diameter, but this is not limited to this configuration. Transport rollers of different diameters may be installed in the heat treatment furnace 10. Furthermore, in this embodiment, the multiple transport rollers 24 are arranged at equal intervals with a constant pitch, but this is not limited to this configuration. Transport rollers with different pitches may be installed in the heat treatment furnace 10.

[0019] As shown in FIG. 1, the circulating conveying device 30 conveys the saggers 2 conveyed from the discharge outlet (i.e., the opening 15b) of the heat treatment furnace 10 to the inlet (i.e., the opening 15a) of the heat treatment furnace 10 via the disassembly device 54, the recovery device 60, the cleaning device 44, the crack detection device 46, the supply device 40, and the stacking device 50. The circulating conveying device 30 includes a plurality of conveying rollers 32 (see FIGS. 5 and 6) and a driving device 36 (see FIG. 2). The conveying rollers 32 are cylindrical, and their axes extend in a direction perpendicular to the conveying direction. The plurality of conveying rollers 32 all 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 by the transmission of the driving force of the driving device 36. The driving device 36 is a driving device (e.g., a motor) that drives the conveying rollers 32. The driving device 36 is connected to the conveying rollers 24 via a power transmission mechanism. When the driving force of the driving device 36 is transmitted to the conveying rollers 32 via a power transmission mechanism (for example, a mechanism using a sprocket and a chain), the conveying rollers 32 rotate. The driving device 36 drives each of the plurality of conveying rollers 32 so that the plurality of conveying rollers 32 rotate at approximately the same speed. In this embodiment, the plurality of conveying rollers 32 all have the same diameter, but this is not limited to such a configuration. Conveying rollers of different diameters may be installed on the conveying path of the circulating conveying device 30. Furthermore, in this embodiment, the plurality of conveying rollers 32 are arranged at equal intervals with a constant pitch, but this is not limited to such a configuration. Conveying rollers may be installed on the conveying path of the circulating conveying device 30 with unequal pitches.

[0020] As shown in FIG. 1, the supply device 40 is disposed between the crack detection device 46 and the stacking device 50. The supply device 40 includes a first supply section 42a and a second supply section 42b. The first supply section 42a and the second supply section 42b are disposed on the conveying path 34 of the circulating conveying device 30. The first supply section 42a is disposed on the upstream side (the +X direction side in FIG. 1) of the supply device 40, and the second supply section 42b is disposed on the downstream side (the -X direction side in FIG. 1) of the supply device 40. The first supply section 42a and the second supply section 42b are disposed in series on the conveying path 34 of the circulating conveying device 30. That is, the sagger 2 is conveyed to the first supply section 42a in the supply device 40, and then conveyed to the second supply section 42b.

[0021] The first supply unit 42a and the second supply unit 42b are devices that supply the material to be treated (i.e., powder) into the sagger 2. The first supply unit 42a and the second supply unit 42b have the same configuration. Either the first supply unit 42a or the second supply unit 42b supplies the material to be treated to the sagger 2, and the other supply unit passes through the sagger 2 without supplying the material to be treated to the sagger 2. Note that the first supply unit 42a and the second supply unit 42b only need to be configured to supply powder into the sagger 2, and there are no particular limitations on the specific structure. For example, the first supply unit 42a and the second supply unit 42b each include a powder supply unit and a leveling unit. The powder supply unit is configured to supply powder into the sagger 2. Specifically, the powder supply unit includes a powder hopper that stores powder, and the powder hopper includes a supply port that drops powder from above the sack 2 into the inside of the sack 2. The supply port is arranged so as to be located above the center of the sack 2 when the sack 2 is placed in the powder supply unit. The powder supply unit includes a positioning device that positions the sack 2 transported to the powder supply unit so as to be located below the supply port. Note that the powder supply unit may be arranged with a plurality of supply ports. The powder supply unit supplies powder into the sack 2 by dropping the powder from above, so that when the powder supply unit supplies powder to the sack 2, the upper surface of the powder in the sack 2 is in a raised state below the supply port. The leveling unit levels the powder supplied into the sack 2 by the powder supply unit. Specifically, the leveling unit is configured to level the upper surface of the powder by pressing the upper surface of the powder in the sagger 2 with the side surface 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 sagger 2 becomes a substantially horizontal plane.

[0022] The stacking device 50 is disposed on the transport path 34 of the circulating transport device 30. The stacking device 50 is disposed between the supply device 40 and the entrance of the heat treatment furnace 10. The stacking device 50 is a device that vertically stacks the saggers 2 to which the materials to be treated are supplied by the supply device 40. As shown in FIG. 5, the stacking device 50 includes a gripping unit 52 and a lifting device 53. The gripping unit 52 abuts against a pair of side surfaces of the sagger 2 to grip the sagger 2. That is, the gripping unit 52 can be opened and closed by an actuator (not shown). When the gripping unit 52 is caused to perform a closing operation, the sagger 2 is gripped, and when the gripping unit 52 is caused to perform an opening operation, the sagger 2 is released. The lifting device 53 is disposed below the gripping unit 52, and lifts and lowers the sagger 2 located on the transport rollers 32 below the gripping unit 52. In this embodiment, the lifting device 53 is a lifter, but it may be, for example, a lifting pin, as long as it can lift and lower the sack 2. The lifting device 53 is configured to be movable in the vertical direction. When the lifting device 53 rises, the upper end of the lifting device 53 passes between the transport rollers 32 and comes into contact with the lower surface of the sack 2 located above the lifting device 53, thereby lifting the sack 2.

[0023] Here, the operation of stacking the sacks 2 by the stacking device 50 will be described. In the following, in order to distinguish between the two sacks 2, the two sacks 2 will be referred to as sacks 2a and 2b in the order in which they are carried into the stacking device 50. For ease of explanation, an example in which the two sacks 2a and 2b are stacked will be described, but the stacking device 50 may stack the sacks 2 in three or more tiers.

[0024] The sacks 2a, 2b to which the material to be treated has been supplied by the supply device 40 are transported into the stacking device 50 by the transport rollers 32. In the supply device 40, the material to be treated is supplied to the sacks 2 in an unstacked state. Therefore, the sacks 2a, 2b are transported into the stacking device 50 in an unstacked state. When the sack 2a, which has been previously transported into the stacking device 50, is transported below the gripping unit 52, the lifting device 53 rises (the state shown in FIG. 5(a)). Then, the upper end of the lifting device 53 comes into contact with the lower surface of the sack 2a, and the sack 2a rises. As a result, the sack 2a leaves the transport rollers 32 and moves above the transport rollers 32 (the state shown in FIG. 5(b)). Next, the gripping unit 52 grips the sack 2a. When the sack 2a is gripped by the gripping unit 52, the lifting device 53 descends. Then, the lifting device 53 moves away from the sack 2 a held by the holding portion 52 .

[0025] Next, sack 2b, which has been carried into stacking device 50 following sack 2a, is transported by conveying rollers 32. When sack 2b is transported below gripper 52, lifting device 53 rises (state of FIG. 5(c)). Then, the upper end of lifting device 53 abuts against the lower surface of sack 2b, and sack 2b rises. When the upper surface of sack 2b abuts against the lower surface of sack 2a (state of FIG. 5(d)), gripper 52 releases grip of sack 2a. Next, lifting device 53 descends. Since sack 2a is not gripped by gripper 52, when lifting device 53 descends, sack 2b and sack 2a are returned to the conveying rollers 32 with sack 2a stacked on sack 2b (state of FIG. 5(e)). Thereafter, the sacks 2a, 2b are transported in a stacked state by the transport rollers 32 to the outside of the stacking device 50. In this manner, the stacking device 50 stacks the multiple sacks 2a, 2b such that the sack 2a transported first is located at the top and the sack 2b transported subsequently is located at the bottom.

[0026] As shown in FIG. 1, the disassembly device 54 is disposed on the conveying path 34 of the circulating conveying device 30. The disassembly device 54 is disposed between the discharge port of the heat treatment furnace 10 and the recovery device 60. The disassembly device 54 is a device for disassembling the saggers 2 stacked in the vertical direction. As shown in FIG. 6, the disassembly device 54 includes a gripping section 56 and a lifting device 57. The gripping section 56 abuts against a pair of side surfaces of the sagger 2 to grip the sagger 2. That is, the gripping section 56 can be opened and closed by an actuator (not shown). When the gripping section 56 is caused to perform a closing operation, the sagger 2 is gripped, and when the gripping section 56 is caused to perform an opening operation, the sagger 2 is released. The lifting device 57 is disposed below the gripping section 56 and lifts and lowers the sagger 2 located on the conveying roller 32 below the gripping section 56. In this embodiment, the lifting device 57 is a lifter, but it may be, for example, a lifting pin, as long as it can lift and lower the sack 2. The lifting device 57 is configured to be movable in the vertical direction. When the lifting device 57 rises, the upper end of the lifting device 57 passes between the transport rollers 32 and comes into contact with the lower surface of the sack 2 located above the lifting device 57, thereby lifting the sack 2.

[0027] Here, the operation of disassembling the stacked saggers 2 by the disassembling device 54 will be described. In the following, in order to distinguish between the two saggers 2, the one located at the top in the stacked state will be referred to as sagger 2c, and the one located at the bottom will be referred to as sagger 2d. Also, for ease of explanation, an example will be described in which two saggers 2c and 2d are disassembled from a stacked state, but the disassembling device 54 may disassemble three or more stacked saggers 2.

[0028] The saggers 2c, 2d removed from the heat treatment furnace 10 are transported in a stacked state into the disassembly device 54 by the transport rollers 32. When the stacked saggers 2c, 2d are transported below the gripping unit 56, the lifting device 57 rises (the state shown in FIG. 6(a)). Then, the upper end of the lifting device 57 comes into contact with the underside of the sagger 2d located at the bottom, and the stacked saggers 2c and 2d rise (the state shown in FIG. 6(b)). Next, the gripping unit 56 grips the upper sagger 2c.

[0029] When the gripping portion 56 grips the sack 2c, the lifting device 57 descends. Then, the sack 2c gripped by the gripping portion 56 remains above the conveying rollers 32 while still being gripped by the gripping portion 56, and only the lower sack 2d not gripped by the gripping portion 56 descends (the state shown in FIG. 6(c)). When the sack 2d is returned onto the conveying rollers 32, only the sack 2d is conveyed by the conveying rollers 32. That is, the sack 2d is conveyed first. Next, the lifting device 57 ascends again (the state shown in FIG. 6(d)). When the upper end of the lifting device 57 abuts against the lower surface of the sack 2c, the gripping portion 56 releases the gripped state of the sack 2c. Next, the lifting device 57 descends. Since sack 2c is not gripped by gripping portion 56, when lifting device 57 descends, sack 2c also descends. Then, sack 2c is placed on conveying rollers 32 (state of FIG. 6(e)). After that, sacks 2c, 2d are conveyed by conveying rollers 32 to the outside of de-staggering device 54 in the order of sacks 2d, 2c. In this way, de-staggering device 54 de-staggers a plurality of sacks 2c, 2d so that sack 2d located at the bottom is conveyed first, followed by sack 2c located at the top.

[0030] 1, the recovery device 60 is disposed between the destacking device 54 and the cleaning device 44. As shown in FIGS. 1 and 7, the recovery device 60 includes a branching section 62, a merging section 64, a first recovery section 66a, a second recovery section 66b, and a control device 68.

[0031] The branching section 62 is disposed upstream of the recovery device 60 and branches the transport path 34 of the circulating transport device 30 into a first transport path 34a and a second transport path 34b. The merging section 64 is disposed downstream of the recovery device 60 and merges the first transport path 34a and the second transport path 34b branched at the branching section 62. The first transport path 34a and the second transport path 34b are provided within the recovery device 60. The first transport path 34a and the second transport path 34b are provided between the branching section 62 and the merging section 64.

[0032] As shown in Fig. 8, a plurality of conveying rollers 32a (hereinafter, the conveying rollers 32a arranged on the first conveying path 34a are also referred to as "first conveying rollers 32a") are arranged on the first conveying path 34a. The first conveying rollers 32a are arranged at intervals in a direction parallel to the conveying path 34 of the circulating conveying device 30 (X direction in Fig. 8) on the upstream and downstream sides of the first collecting section 66a, and the first conveying path 34a is parallel to the conveying path 34 of the circulating conveying device 30. In addition, as shown in Fig. 1, the first conveying path 34a is offset in the +Y direction with respect to the conveying path 34 of the circulating conveying device 30.

[0033] As shown in FIG. 8, a plurality of conveying rollers 32b (hereinafter, the conveying rollers 32b arranged on the second conveying path 34b are also referred to as "second conveying rollers 32b") are arranged on the second conveying path 34b. The second conveying rollers 32b are arranged at intervals in a direction parallel to the conveying path 34 of the circulating conveying device 30 (X direction in FIG. 8) on the upstream and downstream sides of the second collecting section 66b, and the second conveying path 34b is parallel to the conveying path 34 of the circulating conveying device 30. Also, as shown in FIG. 1, the second conveying path 34b is offset in the +Y direction with respect to the conveying path 34 of the circulating conveying device 30. That is, the second conveying path 34b is arranged parallel to the first conveying path 34a, and the first conveying path 34a and the second conveying path 34b are arranged in parallel.

[0034] The first collection unit 66a is disposed on the first transport path 34a, and the second collection unit 66b is disposed on the second transport path 34b. As described above, the first transport path 34a and the second transport path 34b are disposed in parallel, and therefore the first collection unit 66a and the second collection unit 66b are also disposed in parallel.

[0035] The first and second collection sections 66a and 66b are devices that collect the object (i.e., powder) that has been heat-treated in the heat treatment furnace 10 from the sagger 2. The first and second collection sections 66a and 66b have the same configuration. The first and second collection sections 66a and 66b only need to be configured to collect the powder from the sagger 2, and there is no particular limitation on the specific structure. For example, the first and second collection sections 66a and 66b each include an inversion collection section that inverts the sagger 2 in the vertical direction to collect the object, and an air collection section that uses air to peel off and collect the object (powder in this embodiment) that is attached to the surface of the sagger 2. The inversion collection section moves the powder in the sagger 2 to a collection container by inverting the sagger 2 in the vertical direction. As a result, almost all of the powder contained in the sagger 2 moves to the collection container. After that, the inverting and collecting unit inverts the sack 2 again to return it to its original orientation. The air collecting unit is used after the powder in the sack 2 is collected by the inverting and collecting unit. The air collecting unit sucks the air in the sack 2 while blowing air onto the inner surface of the sack 2. By blowing air onto the inner surface of the sack 2, the powder adhering to the inner surface of the sack 2 is peeled off from the inner surface. When the air in the sack 2 is sucked while blowing air onto the inner surface of the sack 2, the powder peeled off from the inner surface of the sack 2 is sucked together with the air. This allows the powder remaining on the inner surface of the sack 2 to be collected, and the powder collection rate to be increased. In the above example, the first collecting unit 66a and the second collecting unit 66b are provided with air collecting units, but are not limited to such a configuration. For example, the powder remaining on the inner surface of the sack 2 may be configured to be peeled off from the inner surface of the sack 2 by a rotating brush and collected.

[0036] 7, the control device 68 is connected to the branching section 62, the merging section 64, the first collection section 66a, and the second collection section 66b. The control device 68 controls the operations of the branching section 62, the merging section 64, the first collection section 66a, and the second collection section 66b.

[0037] Here, the operation of recovering the materials to be treated in the sacks 2 by the recovery device 60 will be described. The sacks 2 are transported by the transport rollers 32 from the de-stack device 54 to the branching section 62 (see FIG. 1). As described above, the de-stack device 54 de-stacks the sacks 2 stacked in the vertical direction. Therefore, the unstacked sacks 2 are transported to the branching section 62. The control device 68 causes the sacks 2 transported to the branching section 62 to be transported to either the first transport path 34a or the second transport path 34b. For example, the control device 68 causes the previously transported sack 2 to be transported to the first transport path 34a, and the subsequently transported sack 2 to be transported to the second transport path 34b.

[0038] When the sagger 2 transported to the first transport path 34a is transported to the first recovery section 66a by the first transport roller 32a, the material to be processed contained in the sagger 2 is recovered in the first recovery section 66a. The sagger 2 is then transported to the junction 64 by the first transport roller 32a. Similarly, when the sagger 2 transported to the second transport path 34b is transported to the second recovery section 66b by the second transport roller 32b, the material to be processed contained in the sagger 2 is recovered in the second recovery section 66b. The sagger 2 is then transported to the junction 64 by the second transport roller 32b. In this way, the two saggers 2 transported to the first transport path 34a and the second transport path 34b branched at the branching section 62 join at the junction 64.

[0039] Next, the control device 68 causes the two sacks 2 transported to the junction 64 (i.e., the sack 2 transported on the first transport path 34a and the sack 2 transported on the second transport path 34b) to be transported onto the transport path 34 of the circulating transport device 30 in a preset order. The vertical order in which the sacks 2 are stacked by the stacking device 50 is determined according to the order in which they are transported from the junction 64 onto the transport path 34 of the circulating transport device 30.

[0040] The relationship between the order of the sacks 2 discharged from the recovery device 60 and the order of the sacks 2 stacked in the stacking device 50 in the vertical direction will be described in more detail. The sacks 2 discharged from the recovery device 60 are transported along the transport path 34 of the circulating transport device 30, and are transported to the stacking device 50 via the cleaning device 44, the crack detection device 46, and the supply device 40. As shown in FIG. 5, in the stacking device 50, the sacks 2a transported first are positioned on top, and the sacks 2b transported next are positioned on the bottom. In the recovery device 60, when the sacks 2 transported along the first transport path 34a and the sacks 2 transported along the second transport path 34b are joined at the joining section 64, the sacks 2 to be stacked on top are first transported onto the transport path 34 of the circulating transport device 30, and the sacks 2 located on the bottom when stacking are transported onto the transport path 34 of the circulating transport device 30 later. In this way, by adjusting the conveying order of the sacks 2 conveyed onto the conveying path 34 of the circulating conveying device 30 at the junction 64, a plurality of sacks 2 can be stacked vertically in a desired order.

[0041] For example, in the conventional heat treatment system, the recovery device is configured so that the saggers 2 are transported along the transport path 34 of the circulating transport device 30 in the recovery device as well. That is, in the conventional heat treatment system, the saggers 2 are transported in series in the recovery device as well. In this case, when the stacked saggers 2 are de-stacked before being transported into the recovery device and then stacked again after being transported out of the supply device, the saggers 2 are stacked in the reverse order to the order in which they were previously stacked. That is, as shown in FIG. 6, in the de-stack device 54, the sagger 2d located at the bottom is transported first, and the sagger 2c located at the top is transported next. The saggers 2d and 2c pass through the recovery device, cleaning device, crack detection device, and supply device, and are transported into the stacking device 50. At this time, the sagger 2d is transported first into the stacking device 50, and the sagger 2c is transported next. As shown in Fig. 5, in the stacking device 50, the sacks are stacked so that the sack 2d (sack 2a in Fig. 5) that is transported first is located on top and the sack 2c (sack 2b in Fig. 5) that is transported next is located on the bottom. That is, the sacks 2c and 2d are stacked vertically in the reverse order to the state before unstacking (i.e., the state shown in Fig. 6(a)).

[0042] In this embodiment, by adjusting the conveying order of the saggers 2 conveyed on the conveying path 34 of the circulating conveying device 30 at the junction 64, the plurality of saggers 2 can be stacked vertically in a desired order. For example, the saggers 2 may have different shapes depending on the position when stacked. Specifically, the sagger 2 located at the top may have a lid placed on its top surface. In this case, the sagger 2 with the lid placed on it may have a different shape from the sagger 2 without the lid (i.e., with another sagger 2 placed on its top surface). Also, even when the sagger 2 located at the top does not have a lid placed on its top surface, the sagger 2 located at the top may not have a notch on its side, and the sagger 2 located at the lower may have a notch on its side. The notch is provided to release gas generated from the object to be treated during heat treatment. The sagger 2 located at the top has an open top because no lid is placed on it. Therefore, it is not necessary to provide a notch in the sack 2 located at the top. In this way, the vertical positions of the sacks 2 may be determined according to the type of the sacks 2, and it becomes necessary to adjust the positions of the sacks 2 so that the sacks 2 are stacked at appropriate positions. In addition, even if the shapes of the sacks 2 are the same, the vertical order of the sacks 2 may be changed to a desired order. For example, the sacks 2 located at the bottom are worn due to contact with the conveying rollers 32 during conveyance, and therefore are more likely to deteriorate than the sacks 2 located at the top. In order to prevent only a specific sack 2 from deteriorating, the vertical order of the sacks 2 may be changed when stacking. In this embodiment, the vertical order of the sacks 2 can be easily adjusted by adjusting the conveying order of the sacks 2 conveyed on the conveying path 34 of the circulating conveying device 30 at the junction 64. That is, it is easy to adjust so that the sacks 2 are stacked in the same order every time, and it is also easy to adjust so that the order is changed every time.

[0043] The cleaning device 44 is a device that cleans the inner surface of the sack 2 after the material to be treated (i.e., powder) has been collected by the collection device 60. The cleaning device 44 may be configured to clean the inner surface of the sack 2, and there is no particular limitation on the specific structure. For example, the cleaning device 44 uses a rotating brush to peel off substances adhering to the inner surface of the sack 2 while sucking in air, etc., from within the sack 2. The sucked in air, etc., contains the peeled off substances. By cleaning the inner surface of the sack 2 with the cleaning device 44, the powder, etc. remaining on the inner surface of the sack 2 can be completely removed.

[0044] The crack detection device 46 is a device for inspecting whether the sack 2 is cracked by detecting the crack in the sack 2. The sack 2 is repeatedly used in the heat treatment furnace 10 for the heat treatment of the object to be treated. The crack detection device 46 inspects whether the sack 2 is cracked after being used in the heat treatment furnace 10 for the heat treatment of the object to be treated and before being reused. The crack detection device 46 may be configured to detect the crack in the sack 2, and the specific configuration is not particularly limited. For example, the crack detection device 46 may detect the crack in the sack 2 using a laser. The crack detection device 46 may also detect the crack in the sack 2 by sealing gas in the sack 2 and measuring the pressure in the sack 2. When the crack in the sack 2 is detected, the sack 2 is taken out from the conveying path 34 of the circulation conveying device 30. If no cracks are detected in the sagger 2, the sagger 2 is transported to the supply device 40 by the circulating transport device 30.

[0045] In this embodiment, the circulating transport device 30 is a roller conveyor that transports the saggers 2 by the transport rollers 32, but is not limited to this configuration. It is sufficient that the circulating transport device is configured to transport the saggers 2 discharged from the discharge outlet of the heat treatment furnace 10 to the inlet of the heat treatment furnace 10, and for example, the circulating transport device may be a belt conveyor that transports the saggers 2 by a belt.

[0046] In this embodiment, the control device 68 of the recovery device 60 adjusts the transport order of the saggers 2 transported from the junction 64 onto the transport path 34 of the circulating transport device 30, but is not limited to this configuration. For example, the management device 48 may adjust the transport order of the saggers 2 transported from the junction 64 onto the transport path 34 of the circulating transport device 30.

[0047] In this embodiment, only the sacks 2 are stacked, but a lid may be placed on the sack 2 located at the topmost stage. In this case, the lid may be destacked by the destack device 54 and placed on the transport path 34 of the circulating transport device 30, and then transported to the stacking device 50 via the same path as the destacked sacks 2, and placed on the sack 2 located at the topmost stage by the stacking device 50. Alternatively, a separate transport path may be provided between the destack device 54 and the stacking device 50, and the lid destacked by the destack device 54 may be transported to the stacking device 50 via the separate transport path.

[0048] Example 2 In the above embodiment, the first transport path 34a and the second transport path 34b are provided in parallel in the recovery device 60, but the configuration is not limited to this. When stacking the saggers 2 destacked by the destack device 54 in the stacking device 50, the vertical order of stacking the saggers 2 may be easily adjusted. For example, as shown in FIG. 9, two transport paths may be provided in parallel in the supply device 140, and two transport paths may not be provided in parallel in the recovery device 160. In the heat treatment system 200 of this embodiment, the supply device 140 and the recovery device 160 are different from the supply device 140 and the recovery device 160 of the heat treatment system 100 of the first embodiment, and the other configurations are substantially the same. Therefore, the description of the same configuration as the heat treatment system 100 of the first embodiment will be omitted.

[0049] The supply device 140 includes a branching section 162, a junction section 164, a first supply section 142a, a second supply section 142b, and a control device (not shown). The branching section 162 is disposed upstream of the supply device 140, and branches the conveying path 34 of the circulating conveying device 30 into a first conveying path 134a and a second conveying path 134b. The junction section 164 is disposed downstream of the supply device 140, and merges the first conveying path 134a and the second conveying path 134b branched at the branching section 162. The first conveying path 134a and the second conveying path 134b are provided in the supply device 140. The first conveying path 134a and the second conveying path 134b are provided between the branching section 162 and the junction section 164. The first supply unit 142a is disposed on the first transport path 134a, and the second supply unit 142b is disposed on the second transport path 134b. The branching unit 162, the junction 164, the first transport path 134a, and the second transport path 134b have substantially the same configurations as the branching unit 62, the junction 64, the first transport path 34a, and the second transport path 34b provided in the recovery device 60 of the above-mentioned first embodiment, and therefore detailed explanations are omitted. The first supply unit 142a and the second supply unit 142b also have substantially the same configurations as the first supply unit 42a and the second supply unit 42b of the above-mentioned first embodiment, and therefore detailed explanations are omitted. In this embodiment, the first transport path 134a and the second transport path 134b are disposed in parallel in the supply device 140, and the first supply unit 142a and the second supply unit 142b are also disposed in parallel.

[0050] The recovery device 160 includes a first recovery section 166a and a second recovery section 166b. The first recovery section 166a and the second recovery section 166b are disposed on the transport path 34 of the circulating transport device 30. That is, the first recovery section 166a and the second recovery section 166b are disposed in series on the transport path 34 of the circulating transport device 30. The first recovery section 166a and the second recovery section 166b have substantially the same configuration as the first recovery section 66a and the second recovery section 66b of the first embodiment, and therefore detailed description thereof will be omitted. Since the first recovery section 166a and the second recovery section 166b have the same configuration, the object to be treated is recovered from the sagger 2 in either the first recovery section 166a or the second recovery section 166b, and the sagger 2 passes through without the object to be treated being recovered from the sagger 2 in the other section.

[0051] In this embodiment, instead of the two parallel transport paths in the collection device 160, the two parallel transport paths 134a, 134b are provided in the supply device 140. The saggers 2 destaggered by the destaggering device 54 are transported in series through the collection device 160, the cleaning device 44 and the crack detection device 46, and then transported to the supply device 140. In the supply device 140, the saggers 2 are branched at the branching section 162 and transported in parallel through one of the two transport paths 134a, 134b, and the order of transport onto the transport path 34 of the circulating transport device 30 is adjusted at the junction 164. The saggers 2 are then transported to the stacking device 50 in the order adjusted at the junction 164. Therefore, in this embodiment as well, the vertical order in which the saggers 2 are stacked can be easily adjusted by adjusting the transport order of the saggers 2 transported onto the transport path 34 of the circulating transport device 30 at the junction 64 provided in the supply device 140.

[0052] Example 3 In the above-mentioned first and second embodiments, the first transport path 34a, 134a and the second transport path 34b, 134b are provided in parallel in only one of the collection device 60, 160 and the supply device 40, 140, but the present invention is not limited to such a configuration. For example, as shown in FIG. 10, in the heat treatment system 300, two transport paths may be provided in parallel in each of the collection device 260 and the supply device 240. The collection device 260 has a substantially identical configuration to the collection device 60 in the above-mentioned first embodiment, and the supply device 240 has a substantially identical configuration to the supply device 140 in the above-mentioned second embodiment. Therefore, detailed description of the collection device 260 and the supply device 240 is omitted. In this embodiment, the vertical order in which the saggers 2 are stacked can be easily adjusted by adjusting the transport order of the saggers 2 transported on the transport path 34 of the circulating transport device 30 at the junction provided in the collection device 260 and the supply device 240.

[0053] Points to note regarding the heat treatment systems 100, 200, and 300 described in the embodiments will be described below. The circulating transport device 30 in the embodiments is an example of a "first transport device" and a "second transport device", the transport mechanism using the transport rollers 32a is an example of a "first transport mechanism", the transport mechanism using the transport rollers 32b is an example of a "second transport mechanism", the first recovery units 66a, 166a and the second recovery units 66b, 166b are an example of a "recovery unit", the first supply units 42a, 142a and the second supply units 42b, 142b are an example of a "supply unit", and the control device 68 is an example of an "adjustment mechanism".

[0054] 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]

[0055] 2: Box 10: Heat treatment furnace 30: Circulation transport device 32, 32a, 32b: conveying rollers 36: Drive unit 40, 140, 240: Feeding device 42a, 142a: 1st supply section 42b, 142b: 2nd supply section 44:Cleaning device 46: Crack detection device 48: Management device 50: Stacking device 54: Disassembly device 60, 160, 260: Recovery device 62, 162: Branch 64, 164: Junction 66a, 166a: First collection section 66b, 166b: Second collection section 68: Control device 100, 200, 300: Heat treatment system

Claims

1. a heat treatment furnace having an inlet and an outlet, for heat-treating the workpieces contained in the vertically stacked saggers while transporting the saggers from the inlet to the outlet; a supply device that supplies the workpiece before heat treatment to the sagger in which the workpiece is not contained; a stacking device that stacks the plurality of saggers to which the material to be treated has been supplied by the supplying device in a vertical direction; a first conveying device that conveys the saggers stacked in the vertical direction by the stacking device to the entrance of the one of the heat treatment furnaces; a stacking device for stacking the plurality of saggers stacked in the vertical direction and discharged from the discharge port of the one heat treatment furnace; a recovery device that recovers the workpiece that has been heat-treated in the one heat treatment furnace from the saggered sagger by the destacking device; a second conveying device that conveys the sagger discharged from the discharge port of the one heat treatment furnace to the disassembly device, At least one of the collecting device and the supplying device includes at least a first conveying mechanism that conveys the sagger along a first conveying path, and a second conveying mechanism that conveys the sagger along a second conveying path different from the first conveying path, A heat treatment system, wherein each of the first transport path and the second transport path is provided with a recovery section that recovers the workpiece in the sagger or a supply section that supplies the workpiece into the sagger.

2. a branching section provided upstream of the first conveying path and the second conveying path, the branching section branching the sagger to one of the first conveying path and the second conveying path; The heat treatment system of claim 1 , further comprising a junction section provided downstream of the first transport path and the second transport path, which joins the saggers transported along the first transport path with the saggers transported along the second transport path.

3. A heat treatment furnace having an inlet and an outlet, for heat-treating the workpiece contained in the vertically stacked saggers while transporting the saggers from the inlet to the outlet; a supply device that supplies the workpiece before heat treatment to the sagger in which the workpiece is not contained; a stacking device that stacks the plurality of saggers to which the material to be treated has been supplied by the supplying device in a vertical direction; a first conveying device that conveys the saggers stacked in the vertical direction by the stacking device to the entrance of the heat treatment furnace; a stacking device for stacking the plurality of saggers stacked in the vertical direction and discharged from the discharge port of the heat treatment furnace; a recovery device that recovers the workpiece that has been heat-treated in the heat treatment furnace from the saggered sagger by the destacking device; a second conveying device that conveys the sagger discharged from the discharge port of the heat treatment furnace to the disassembly device, At least one of the collecting device and the supplying device includes at least a first conveying mechanism that conveys the sagger along a first conveying path, and a second conveying mechanism that conveys the sagger along a second conveying path different from the first conveying path, A recovery unit that recovers the object to be treated in the sagger or a supply unit that supplies the object to be treated in the sagger is provided on each of the first transport path and the second transport path, a branching section provided upstream of the first conveying path and the second conveying path, the branching section branching the sagger to one of the first conveying path and the second conveying path; The heat treatment system further includes a junction section provided downstream of the first transport path and the second transport path, which joins the saggers transported along the first transport path with the saggers transported along the second transport path.

4. The heat treatment system of claim 2 or 3, wherein at least one of the first transport path and the second transport path is further provided with an adjustment mechanism for adjusting the order in which the saggers transported along the first transport path and the saggers transported along the second transport path are transported into the junction.

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