JP7373517B2 - Batch heat treatment furnace and heat treatment furnace system - Google Patents

Description

The technology disclosed herein relates to a batch heat treatment furnace for heat treating objects to be treated (for example, laminated ceramic parts such as ceramic capacitors, ceramic piezoelectric elements, ceramic resistors, etc.).

When heat-treating multiple workpieces placed in a furnace at the same time, in order to stabilize the properties of the multiple workpieces after heat treatment, it is necessary to give each of the multiple workpieces the same thermal history. There is a need. For this reason, in the batch heat treatment furnace of Patent Document 1, the hearth on which the object to be treated is placed is composed of a main hearth and a sub-hearth. The main hearth has a circular shape when viewed from above, and is rotatable around an axis passing through its center. The secondary hearth is located in an opening formed in the main hearth. The sub-hearth has a circular shape when viewed from above, and is rotatable around an axis passing through its center. The object to be processed is placed on the upper surface of the sub-hearth. When heat treating a material to be treated, the secondary hearth itself rotates (so-called autorotation), and as the main hearth rotates, the secondary hearth also rotates around an axis passing through the center of the main hearth (so-called revolution). do. As a result, the plurality of objects placed on the upper surface of the auxiliary hearth are heated uniformly, and the same thermal history is imparted to each object.

Japanese Patent Application Publication No. 2005-77001

By the way, in order to heat treat a workpiece in a batch type heat treatment furnace, the workpiece is placed in the heat treatment furnace, the workpiece installed in the furnace is heat treated, and the workpiece after heat treatment is transferred to the heat treatment furnace. It is necessary to take it outside. In order to streamline the installation of objects to be processed into the furnace and the removal of them out of the furnace, the processing table is made removable from the floor of the furnace body, and the objects to be processed are placed on the removable processing table. It is being considered that the However, when adopting a configuration in which the processing table is removably attached to the floor of the furnace body, a drive device for rotationally driving the processing table is provided on the floor of the furnace body. Therefore, in order to attach the processing table to the floor of the furnace body, the processing table must be connected to the drive part of the drive unit in the rotational direction, and the processing table must be connected to the floor of the furnace body. A problem arises in that the work for attaching it to a surface becomes complicated.

This specification discloses a technique that allows easy installation of a processing table in a batch heat treatment furnace in which the processing table is removable from the floor of the furnace body.

A first batch heat treatment furnace disclosed in this specification includes a furnace body including a ceiling wall, a side wall, and an elevating floor, and a processing table that is rotatably arranged with respect to the elevating floor and on which a workpiece can be placed. a drive device that is provided on the elevating floor and to which the processing table is detachably connected and rotates the processing table; a position sensor that detects the rotational position of the processing table with respect to the elevating floor; and a position sensor that detects the position sensor. and a control device that controls the drive device based on the results. The processing table has a circular shape when viewed from above, and includes a first rotary table configured to be rotatable around a first axis extending vertically through the center thereof; At least one second rotary table is arranged inside the first rotary table and configured to be rotatable around a second axis extending vertically through the center of the first rotary table. When viewed in plan, the center position of the second rotary table is at a different position from the center position of the first rotary table. The elevating floor is movable between a first position where the lower end of the side wall is open and a second position where the lower end of the side wall is closed. When the elevating floor is in the first position, the processing table can be attached to and detached from the drive device. When the elevating floor is located at the second position with the processing table connected to the drive device, the upper surface of the first rotary table and the upper surface of the second rotary table are exposed within the furnace body. The drive device includes a first drive section that is arranged on a first axis and rotates the first rotary table, and a second drive section that is arranged on the second axis and rotationally drives the second rotary table. It is equipped with. The position sensor outputs a detection signal when the first rotary table is within a preset angle range with respect to the elevating floor.
When stopping the rotation of the first rotary table from a state where the first rotary table is rotating at a first speed in a first rotation direction, the control device (1) outputs the detection signal from the position sensor. is output, the first rotary table further rotates in the first rotation direction while the detection signal is output, and when the output detection signal stops, the first rotary table is stopped. , (2) After the above (1), the first rotary table is rotated in a second rotation direction opposite to the first rotation direction at a second speed lower than the first speed. (3) When the detection signal is output from the position sensor in the state (2), the first rotary table is stopped.

In the above first batch heat treatment furnace, for example, when heat treating a workpiece, the first rotary table can be rotated at a first speed corresponding to the heat treatment desired to be performed on the workpiece. On the other hand, when the first rotary table is stopped after the heat treatment of the workpiece is finished, follow the steps (1) to (3) above to change the state from rotating in the second direction at the second speed to the first rotary table. stop the rotary table. The second speed may be lower than the first speed and may be a constant speed that is independent of the heat treatment performed on the object. Therefore, the first rotary table stops when its position in the rotation direction is at a predetermined position (angle), and the drive unit (first drive unit) of the drive device connected to the first rotary table stops. The second drive unit) also stops at an angle corresponding to the predetermined angle. Therefore, when attaching the first rotary table, the processing table can be connected to the drive section of the drive device by adjusting the processing table to a predetermined angle in advance. This makes it possible to easily attach the processing table to the drive device.

The second batch heat treatment furnace disclosed in this specification includes a furnace body including a ceiling wall, a side wall, and an elevating floor, and a processing table that is rotatably arranged with respect to the elevating floor and on which a workpiece can be placed. a drive device that is provided on the elevating floor and to which the processing table is detachably connected and rotates the processing table; a position sensor that detects the rotational position of the processing table with respect to the elevating floor; and a position sensor that detects the position sensor. and a control device that controls the drive device based on the results. The processing table has a circular shape when viewed from above, and includes a first rotary table configured to be rotatable around a first axis extending vertically through the center thereof; At least one second rotary table is arranged inside the first rotary table and configured to be rotatable around a second axis extending vertically through the center of the first rotary table. When viewed in plan, the center position of the second rotary table is at a different position from the center position of the first rotary table. The elevating floor is movable between a first position where the lower end of the side wall is open and a second position where the lower end of the side wall is closed. When the elevating floor is in the first position, the processing table can be attached to and detached from the drive device. When the elevating floor is located at the second position with the processing table connected to the drive device, the upper surface of the first rotary table and the upper surface of the second rotary table are exposed within the furnace body. The drive device includes a first drive section that is arranged on a first axis and rotates the first rotary table, and a second drive section that is arranged on the second axis and rotationally drives the second rotary table. It is equipped with. The position sensor outputs a detection signal when the first rotary table is within a preset angle range with respect to the elevating floor.
When the control device stops the rotation of the first rotary table from a state in which the first rotary table is rotating at a first speed in a first rotation direction, (1) a detection signal is output from the position sensor; (2) After (1), the first rotary table is rotated in a second direction opposite to the first rotation direction. (3) When the detection signal output from the position sensor stops in the state of (2) above, the first rotary table is stopped; (4) After (3) above, the first rotary table is turned to the first rotary table. (5) When a detection signal is output from the position sensor in the state (4) above, the first rotary table is stopped. It is configured as follows.

Also in the second batch type heat treatment furnace described above, when heat treating the workpiece, the first rotary table can be rotated at a first speed corresponding to the heat treatment desired to be performed on the workpiece. On the other hand, when the first rotary table is stopped after the heat treatment of the workpiece is finished, the first rotary table is rotated from the state of rotating in the first direction at the second speed according to the steps (1) to (5) above. stop the rotary table. The second speed may be lower than the first speed and may be a constant speed that is independent of the heat treatment performed on the object. Therefore, in the second batch heat treatment furnace as well, when the first rotary table is attached, the drive section of the drive device is at an angle corresponding to a predetermined angle. Therefore, it is possible to easily attach the processing table to the drive device.

Note that in the first batch heat treatment furnace or the second batch heat treatment furnace described above, the processing table may include a plurality of second rotary tables. The plurality of second rotary tables may be arranged at different positions of the first rotary table without interfering with each other when viewed in plan.

Further, the heat treatment furnace system disclosed in this specification includes a plurality of batch type heat treatment furnace bodies and at least one processing table that is detachable from each of the plurality of batch type heat treatment furnace bodies. The processing table may be a processing table installed in the first batch heat treatment furnace or the second batch heat treatment furnace. Further, each of the plurality of batch heat treatment furnace bodies may include a furnace body, a drive device, a position sensor, and a control device, which are installed in the first batch heat treatment furnace or the second batch heat treatment furnace. . In the above heat treatment furnace system, a processing table can be shared by a plurality of batch type heat treatment furnace bodies.

Further, the heat treatment furnace system may further include a transport vehicle that transports the processing table to each of the plurality of batch type heat treatment furnace bodies. Since the processing table can be shared, the transport vehicle for transporting the processing table can also be used.

1 is a schematic diagram showing a schematic configuration of a heat treatment furnace system according to Example 1. FIG. 1 is a schematic diagram showing a batch-type heat treatment furnace main body according to Example 1, a processing table that is removably installed in the heat treatment furnace main body, and a carrier that transports the processing table. A sectional view showing a state in which a processing table is installed in the heat treatment furnace main body (a state in which the elevating floor is lowered). FIG. 2 is a sectional view showing a state in which a processing table is installed in the heat treatment furnace main body (a state in which the elevating floor is raised). FIG. 4 is a cross-sectional view of the heat treatment furnace body in which the processing table is installed (VV cross-sectional view in FIG. 4). FIG. 2 is a side view showing a state in which a processing table is installed on an elevating floor (however, illustration of the drive device (20, 22) is omitted). FIG. 7 is a plan view showing a state in which the processing table is installed on the elevating floor (a view of the processing table and the elevating floor viewed from above in FIG. 6); FIG. 3 is a schematic diagram showing a schematic configuration of a connecting section that connects a processing table and a drive mechanism (a diagram showing a state in which the processing table and drive mechanism are not connected); FIG. 3 is a schematic diagram showing a schematic configuration of a connecting section that connects a processing table and a drive mechanism (a diagram showing a state in which the processing table and the drive mechanism are connected); 1 is a block diagram showing the configuration of a control system of a heat treatment furnace main body according to Example 1. FIG. 2 is a flowchart showing the procedure of a stop process performed by a control unit when stopping rotation of a processing table in the heat treatment furnace main body according to the first embodiment. 5 is a timing chart for explaining the relationship between the drive state of the drive device and the signal output from the position sensor when a stop signal is received from the production control device in the heat treatment furnace main body according to the first embodiment. 7 is a flowchart showing the procedure of a stop process performed by a control unit when stopping rotation of a processing table in the heat treatment furnace main body according to the second embodiment. 7 is a timing chart for explaining the relationship between the drive state of the drive device and the signal output from the position sensor when a stop signal is received from the production control device in the heat treatment furnace main body according to the second embodiment.

(Example 1) Hereinafter, a heat treatment furnace system 100 according to this example will be described. First, the schematic configuration of the heat treatment furnace system 100 will be described. As shown in FIG. 1, the area where the heat treatment furnace system 100 is installed includes a loading area A, an unloading area B, and a heat treatment area C. The heat treatment furnace system 100 includes a plurality of processing tables 30, a plurality of heat treatment furnace bodies 10 installed in a heat treatment area C, and a carrier 70 that transports the processing tables 30 between areas A, B, and C. We are prepared.

The processing table 30 has an upper surface on which the object W to be processed is placed. On the upper surface of the processing table 30, in the loading area A, the workpiece W to be processed before being heat-treated is placed. The processing table 30 on which the object to be processed W is placed is transported to the heat treatment area C by a transport vehicle 70. The heat treatment area C is provided with a conveyance path connecting the loading area A and the unloading area B, and a plurality of heat treatment furnace bodies 10 are installed along the conveyance path. The heat treatment furnace main body 10 is a batch type heat treatment furnace, and is used to heat treat the object W to be treated. In this embodiment, a processing table 30 can be attached to each of the plurality of heat treatment furnace bodies 10. Therefore, an appropriate heat treatment furnace body 10 to which the processing table 30 is attached is selected depending on the operating status of the heat treatment furnace system 100. The processing table 30 transported to the heat treatment area C is transported to the selected heat treatment furnace main body 10 and is attached to the selected heat treatment furnace main body 10. When the processing table 30 is attached, the heat treatment furnace main body 10 performs heat treatment on the workpiece W placed on the processing table 30. When the heat treatment on the workpiece W is completed, the processing table 30 is then taken out from the heat treatment furnace main body 10. The processing table 30 that has been taken out is transported to the loading/unloading area B by the transport vehicle 70, and is unloaded to the loading/unloading area B together with the processing table 30.

As is clear from the above, the heat treatment furnace system 100 of the present embodiment includes a plurality of heat treatment furnace bodies 10 and a plurality of processing tables 30 that are detachably attached to each of the plurality of heat treatment furnace bodies 10. There is. Therefore, while the heat treatment furnace main body 10 is in operation (for example, while the workpiece W is being heat-treated), the workpiece W to be heat-treated next can be placed on another processing table 30 to prepare it. Further, after the heat treatment of the workpiece W, the processing table 30 on which the workpiece W after the heat treatment is placed can be removed from the heat treatment furnace main body 10. For this reason, a new processing table 30 (that is, the processing table 30 on which the workpiece W before heat treatment was placed) is attached to the heat treatment furnace main body 10 after the processing table 30 has been removed, and the next workpiece W Heat treatment can be performed. Therefore, according to the heat treatment furnace system of this embodiment, the plurality of heat treatment furnace bodies 10 can be operated efficiently, and the workpiece W can be efficiently heat treated. Note that the processing table 30 removed from the heat treatment furnace main body 10 is left in the unloading area B, so that the workpiece W after heat treatment can be cooled.

On the other hand, if the processing table 30 is shared by a plurality of heat treatment furnace bodies 10, it becomes necessary to attach the processing table 30 to the heat treatment furnace body 10. The processing table 30 of this embodiment includes a main hearth 34 and a sub-hearth 36 as described later, and in order to attach the processing table 30 to the heat treatment furnace main body 10, It is necessary to position accurately in the direction of rotation. Therefore, in the heat treatment furnace main body 10 of this embodiment, when the rotation of the processing table 30 is stopped, the processing table 30 is stopped at a preset position (position in the rotational direction). This facilitates the work of attaching the processing table 30 to the heat treatment furnace main body 10. Hereinafter, the processing table 30, the transport carriage 70, and the heat treatment furnace main body 10 will be explained in detail.

First, the processing table 30 will be explained. As shown in FIGS. 6 to 9, the processing table 30 includes a main hearth 34 and four auxiliary hearths 36 installed on the main hearth 34. The main hearth 34 has a small diameter part 33 located at the upper end and a large diameter part 32 located below the small diameter part 33. The small diameter portion 33 and the large diameter portion 32 have a disc-shaped outer shape and are integrated so that their central axes are located on the same straight line. A recess 34a is formed at the center of the lower surface of the large diameter portion 32 and is engageable with a drive mechanism 20 of the heat treatment furnace main body 10, which will be described later. Further, a dog 38 is attached to the lower surface of the large diameter portion 32 (see FIGS. 6 and 7). The upper end of the dog 38 is fixed near the outer peripheral edge of the large diameter portion 32, and the lower end extends downward from the lower surface of the large diameter portion 32. The circumferential position of the large diameter portion 32 to which the dog 38 is fixed serves as a reference position for controlling the rotation stop position of the processing table 30. When the processing table 30 is attached to the heat treatment furnace body 10, the main hearth 34 (the small diameter part 33 and the large diameter part 32) moves vertically through its central axis (that is, through the center of the small diameter part 33 and the large diameter part 32). (line extending in the direction) coincides with the axis of the heat treatment furnace body 10.

The auxiliary hearth 36 has a disc-like shape and is rotatably installed with respect to the main hearth 34 . Specifically, a through hole is formed in the main hearth 34 from its upper end surface (small diameter portion 33) to its lower end surface (large diameter portion 32), and the auxiliary hearth 36 is formed in the through hole. is arranged so that it can rotate. That is, each of the auxiliary hearths 36 is rotatable around its axis (that is, a line extending vertically through the center of the auxiliary hearth 36). In this embodiment, the four sub-hearths 36 are installed at equal intervals in the circumferential direction (that is, the four sub-hearths 36 are installed at 90° intervals in the circumferential direction). Each of the four auxiliary hearths 36 has an engagement surface 36a at its lower end that can be engaged with a drive mechanism 20, which will be described later (see FIGS. 8 and 9). Each of the axes of the four auxiliary hearths 36 is parallel to the axis of the main hearth 34 and arranged at equal distances from the axis of the main hearth 34 . The upper surface of the main hearth 34 and the upper surface of the auxiliary hearth 36 are flush with each other, and the workpiece W can be placed on the upper surface of the auxiliary hearth 36.

The rotation direction and rotation speed of each of the main hearth 34 and the auxiliary hearth 36 can be changed and stopped. Since the object W to be processed is placed on the upper surface of the auxiliary hearth 36, the object W to be processed rotates as the main hearth 34 rotates, and the object W to be processed rotates as the auxiliary hearth 36 rotates. It will do what is called rotation. The rotation direction of each hearth 34, 36 can be set arbitrarily. For example, as shown in FIG. 5, both the main hearth 34 and the auxiliary hearth 36 may rotate counterclockwise, or the main hearth 34 and the auxiliary hearth 36 may both rotate clockwise. . Alternatively, the main hearth 34 may rotate clockwise while the secondary hearth 36 rotates counterclockwise, or the main hearth 34 rotates counterclockwise while the secondary hearth 36 rotates clockwise. It may be rotated. By appropriately controlling the rotational speed and direction of the main hearth 34 and the sub-hearth 36, the workpiece W placed on the sub-hearth 36 can be heated uniformly.

As is clear from the above description, when the main hearth 34 rotates, the auxiliary hearth 36 also rotates (revolutions) around the axis of the main hearth 34 accordingly. Therefore, when the position at which the main hearth 34 stops rotating changes, the position at which the sub-hearth 36 stops also changes. As described above, the recess 34a is formed on the lower surface of the main hearth 34, and the engaging surface 36a is formed on the lower surface of the auxiliary hearth 36, and each of the recess 34a and the engaging surface 36a is connected to the heat treatment furnace. It is connected to the drive mechanism 20 of the main body 10. Therefore, if the main hearth 34 stops rotating at the same position, the auxiliary hearth 36 stops at the same position, and when the processing table 30 is connected to the drive mechanism 20 of the heat treatment furnace main body 10. alignment can be facilitated.

Note that the processing table 30 described above is transported by a transport vehicle 70 operated by an operator. As shown in FIG. 2, the transport vehicle 70 includes an arm 72 that holds the processing table 30. As shown in FIG. The arm 72 can move up and down, and by moving the arm 72 up and down, the processing table 30 held by the arm 72 moves up and down. By raising and lowering the processing table 30, the processing table 30 can be attached to and detached from the drive mechanism 20 (described in detail later) of the heat treatment furnace main body 10.

Next, the heat treatment furnace main body 10 will be explained. As shown in FIGS. 2 to 5, the heat treatment furnace main body 10 includes a pedestal 16 and a furnace body 11 supported by the pedestal 16. The pedestal 16 is installed at a predetermined position in the heat treatment area C. By supporting the furnace body 11 with the pedestal 16, a space is formed below the furnace body 11 in which the processing table 30 can be attached and detached.

The furnace body 11 is made of refractory material and includes a cylindrical side wall 14 and a disk-shaped ceiling wall 12. The lower end of the side wall 14 is fixed to the frame 16, and the upper end extends to the ceiling wall 12. The ceiling wall 12 contacts the upper end of the side wall 14 and closes the opening at the upper end of the side wall 14. An exhaust port (not shown) is formed in the center of the ceiling wall 12.

The furnace body 11 further includes an elevating floor 18. The elevating floor 18 is formed in a rectangular box shape when viewed from above, and a driving device (20, 22) for rotationally driving the processing table 30 is housed inside the elevating floor 18. The drive device (20, 22) includes a drive source 22 and a drive mechanism 20. The drive source 22 is a general-purpose motor (that is, a motor without a servo function) for rotationally driving the processing table 30. The driving force generated by the drive source 22 is transmitted to the processing table 30 (specifically, each of the main hearth 34 and the auxiliary hearth 36) via the drive mechanism 20.

As shown in FIGS. 8 and 9, the drive mechanism 20 includes a first connecting portion 46 connected to the recess 34a of the main hearth 34, and a second connecting portion 44 connected to the lower surface of the auxiliary hearth 36. ing. The rotational driving force of the drive source 22 is transmitted to the first connecting portion 46 via a transmission member (such as a chain) not shown. A disk-shaped support plate 48 is fixed to the lower end of the first connecting portion 46 . The support plate 48 comes into contact with the lower surface of the main hearth 34 and supports the main hearth 34 . A second drive shaft 42 is fixed to the lower surface of the second connecting portion 44 . The second drive shaft 42 passes through an unillustrated through hole of the support plate 48, and the rotational driving force of the drive source 22 is transmitted to the lower end of the second drive shaft 42 via an unillustrated transmission member (such as a chain). By transmitting the rotational driving force of the drive source 22 to each of the first connecting portion 46 and the second connecting portion 44, the main hearth 34 rotates (rotates), and the auxiliary hearth 36 rotates and revolves accordingly. I will do it.

The recess 34a of the processing table 30 (main hearth 34) is connected to the first connection part 46, and the engagement surface 36a of the processing table 30 (secondary hearth 36) is connected to the second connection part 44, so that A processing table 30 is attached to the drive mechanism 20. As a result, the processing table 30 is placed on the upper surface of the support plate 48 of the drive mechanism 20, and the processing table 30 is supported by the drive mechanism 20. When the processing table 30 is attached to the drive mechanism 20, the processing table 30 is supported above the elevating floor 18, as shown in FIGS. 2 to 4. Here, the elevating floor 18 is moved between a position near the lower end of the furnace body 11 (an example of a second position in the claims) and a position near the floor surface (an example of the second position in the claims) by an elevating device 24 provided on the pedestal 16. (an example of the first position). When the elevating floor 18 is positioned near the floor surface, the lower end of the side wall 14 is opened and the processing table 30 can be attached to and detached from the drive mechanism 20 (the state shown in FIG. 3).

Further, when the elevating floor 18 is positioned near the lower end of the furnace body 11 with the processing table 30 attached to the drive mechanism 20, the processing table 30 closes the lower end opening of the side wall 14 (as shown in FIG. situation). When the processing table 30 closes the lower end opening of the side wall 14, the processing table 30 and the furnace body 12 form a furnace space 26 in which the workpiece W is heat-treated. As shown in FIGS. 4 and 5, the upper surface of the main hearth 34 and the upper surface of the auxiliary hearth 36 are exposed in the furnace space 26, and the workpiece W placed on the upper surface of the auxiliary hearth 36 is exposed. It is accommodated in the furnace space 26. A heater 50 (not shown in FIG. 10) and a gas supply device 52 (not shown in FIG. 10) are provided in the furnace space 26. The workpiece W is heated by the heater 50, and the atmosphere in the furnace space 26 is controlled by the gas supply device 52.

As shown in FIGS. 6 and 7, the elevating floor 18 is provided with a position sensor 40 for detecting the dog 38 attached to the processing table 30. The detection signal output from the position sensor 40 is turned ON when facing the dog 38, and turned OFF when not facing the dog 38. As shown in FIG. 7, since the dog 38 is a plate material having a constant width, the detection signal output from the position sensor 40 is ON when the main hearth 34 is within a preset angle range. .

As shown in FIG. 10, the heat treatment furnace main body 10 further includes a control section 54. The control unit 54 is configured by, for example, a computer including a CPU, ROM, and RAM. The control unit 54 is connected to the production control device 60 and the position sensor 40, and receives instructions from the production control device 60 and detection signals from the position sensor 40. The control unit 54 controls the operation of each part of the heat treatment furnace main body 10 based on input instructions and detection signals. That is, the control unit 54 raises and lowers the elevator floor 18 by controlling the elevator device 24, controls the rotation of the processing table 30 by controlling the drive devices (20, 22), and controls the heater 50 and the gas supply device 52. The temperature and atmosphere inside the furnace are controlled by controlling the temperature and atmosphere inside the furnace. Note that this embodiment is characterized by the operation of the control unit 54 (stopping process) when stopping the rotation of the processing table 30, and other aspects are the same as those of the prior art. Therefore, only the stopping process for stopping the rotation of the processing table 30 will be described in detail.

FIG. 11 shows an example of a stop process performed by the control unit 54 when stopping the rotation of the processing table 30. As shown in FIG. 11, the control unit 54 first monitors whether a stop signal has been received from the production control device 60 (S10). That is, the production control device 60 of this embodiment controls the heat treatment performed on the workpiece W in each heat treatment furnace body 10, and when the desired heat treatment is completed in each heat treatment furnace body 10, the heat treatment is performed. A stop signal is output to the furnace body 10 to stop the heat treatment. First, the control unit 54 monitors whether a stop signal from the production control device 60 has been received in S10. When the stop signal is not received (NO in S10), the control unit 54 continues to drive the drive devices (20, 22) and rotates the processing table 30 in the normal rotation direction at a speed V1. Note that the speed V1 is the rotational speed of the processing table 30 when heat-treating the object W to be processed, and is set to a speed corresponding to the heat treatment of the object W to be processed. Therefore, the speed V1 is appropriately set depending on the type of heat treatment to be performed on the object W to be treated.

Upon receiving the stop signal (YES in S10), the control unit 54 then monitors whether the detection signal output from the position sensor 40 is turned ON (S12). As described above, in this embodiment, when receiving the stop signal, the processing table 30 is rotating in the normal rotation direction at the speed V1 set for heat treatment. Therefore, even if the rotation of the processing table 30 is stopped immediately after receiving the stop signal, the speed V1 is set as appropriate depending on the type of heat treatment, etc., resulting in variations in the position (angular position) at which the processing table 30 stops. . In this embodiment, the rotation of the processing table 30 is not stopped immediately upon reception of a stop signal, but first the rotation of the processing table 30 is continued and the signal from the position sensor 40 is monitored to see if it is turned ON. do.

When the detection signal output from the position sensor 40 turns ON (YES in S12), the control unit 54 next monitors whether the detection signal output from the position sensor 40 turns OFF (S14). That is, the processing table 30 continues to rotate in the normal rotation direction until the dog 38 fixed to the lower surface of the processing table 30 is at a position where it does not face the position sensor 40.

When the detection signal output from the position sensor 40 turns OFF (YES in S14), the control unit 54 stops driving the drive devices (20, 22) and stops the normal rotation of the processing table 30 ( S16). Next, the control unit 54 drives the drive device (20, 22) in the opposite direction to rotate the processing table 30 in the reverse direction at a speed V2 (S18). Here, in order to improve the accuracy with which the processing table 30 is stopped, the speed V2 is a constant value regardless of the heat treatment, and is set to a value smaller than the speed V1.

Next, the control unit 54 monitors whether the detection signal output from the position sensor 40 is turned on (S20). If the detection signal output from the position sensor 40 is OFF (NO in S20), the control unit 54 continues driving the drive device (20, 22) and rotates the processing table 30 in the reverse direction at a speed V2. . On the other hand, when the detection signal output from the position sensor 40 turns ON (YES in S20), the control unit 54 stops driving the drive device (20, 22) and stops the rotation of the processing table 30 in the reverse direction. (S22).

FIG. 12 is a timing chart showing changes in the state of the stop signal, the state of the drive device (20, 22), and the state of the detection signal from the position sensor 40 when the control unit 54 executes the above-described stop processing. It is. As shown in FIG. 12, the drive device (20, 22) rotates the processing table 30 in the normal rotation direction at a speed V1. In this state, even if a stop signal is output from the production control device 60, the drive device (20, 22) rotates the processing table 30 at the speed V1 in the normal rotation direction. Then, when the detection signal from the position sensor 40 turns ON and then turns OFF, the drive device (20, 22) stops the rotation of the processing table 30 in the normal rotation direction. Next, the drive device (20, 22) rotates the processing table 30 in the reverse direction at a speed V2 (<V1), and when the detection signal from the position sensor 40 turns ON, the drive device (20, 22) rotates the processing table 30 in the reverse direction. make it stop. Since the processing table 30 is stopped from rotating at a constant and relatively small rotational speed V2 regardless of heat treatment, the processing table 30 is accurately positioned at a preset position (angular position). Can be stopped. Note that the accuracy of the stop position of the processing table 30 can be improved by using a servo motor as the drive source 22, but by executing the stop processing of this embodiment, the drive source 22 can be a general-purpose motor without a servo function. Even if the processing table 30 is used, the accuracy of the stop position of the processing table 30 can be improved.

The heat treatment furnace system 100 of this embodiment includes a plurality of heat treatment furnace bodies 10 and a plurality of processing tables 30 that are shared by each of the plurality of heat treatment furnace bodies 10. Therefore, the plurality of heat treatment furnace bodies 10 can be operated efficiently to efficiently heat treat the object W to be treated. Further, it is necessary to attach the processing table 30 to the heat treatment furnace body 10, but as described above, the position at which the processing table 30 stops rotating is controlled to be a preset position. In particular, the rotational speed of the processing table 30 when the processing table 30 stops rotating is not the rotational speed V1 during the heat treatment, but is a constant rotational speed V2 smaller than the rotational speed V1. Thereby, the processing table 30 can be stopped at a precisely set position. Therefore, the work of attaching the processing table 30 to the heat treatment furnace main body 10 can be facilitated. For example, if the processing table 30 is held in a preset positional relationship with respect to the carrier 70, then the carrier 70 can be simply positioned in a predetermined positional relationship with respect to the heat treatment furnace main body 10, and the drive mechanism 20 can be The processing table 30 can be positioned in a connectable positional relationship. As a result, the work of attaching the processing table 30 to the heat treatment furnace main body 10 can be facilitated.

Note that in the embodiment described above, the operator operated the transport vehicle 70 and connected the processing table 30 to the drive mechanism 20 of the heat treatment furnace main body 10, but the technology disclosed in this specification is not limited to this. It is not limited to any form. For example, the transport vehicle may be automated so that the transport vehicle autonomously connects the processing table 70 to the drive mechanism 20. In particular, when the technology disclosed herein is used, when the processing table 70 stops rotating, the position (angular position) of the processing table 70 stops at a predetermined position (angular position). Therefore, by simply holding the processing table 30 in a preset positional relationship with respect to the transport vehicle 70 and positioning the transport vehicle 70 in a predetermined positional relationship with respect to the heat treatment furnace main body 10, The processing table 30 can be positioned at an appropriate position. This makes it possible to automate the transport vehicle and save labor in the heat treatment furnace system.

(Example 2) Next, a heat treatment furnace system according to Example 2 will be described. The heat treatment furnace system of Example 2 differs from Example 1 only in the stop processing performed by the control unit when stopping the rotation of the processing table, and is otherwise different from the heat treatment furnace system 100 of Example 1. They have the same configuration. In the following, only the stop processing performed by the control unit of the second embodiment will be described. Note that the same components as in the first embodiment will be described using the same reference numerals.

FIG. 13 shows the procedure of a stop process performed by the control unit 54 when stopping the rotation of the processing table 30. As shown in FIG. 13, the control unit 54 first monitors whether a stop signal has been received from the production control device 60 (S24). When the stop signal has not been received (NO in S24), the control unit 54 continues to drive the drive devices (20, 22) and rotates the processing table 30 in the normal rotation direction at a speed V1. On the other hand, upon receiving the stop signal (YES in S24), the control unit 54 monitors whether the detection signal output from the position sensor 40 is turned ON (S26). Then, when the detection signal output from the position sensor 40 turns ON (YES in S26), the control unit 54 immediately stops the drive device (20, 22) and stops the rotation of the processing table 30 (S28). Therefore, when the rotation of the processing table 30 is stopped in S28, the detection signal output from the position sensor 40 remains ON.

Next, the control unit 54 drives the drive devices (20, 22) in the reverse direction to rotate the processing table 30 in the reverse direction at a speed V1 (S30). Then, the control unit 54 monitors whether the detection signal output from the position sensor 40 is turned off (S32). That is, at the time of S30, the detection signal output from the position sensor 30 is ON. Therefore, in S32, it is monitored whether the detection signal output from the position sensor 40 has changed from ON to OFF.

When the detection signal output from the position sensor 40 turns OFF (YES in S32), the control unit 54 immediately stops driving the drive device (20, 22) in the reverse direction, and stops the rotation of the processing table 30 in the reverse direction. It is stopped (S34). Next, the control unit 54 drives the drive devices (20, 22) in the forward direction to rotate the processing table 30 in the forward direction at a speed V2 (S36). The speed V2 is a constant value regardless of the type of heat treatment, etc., and is set to a smaller value than the speed V1.

Next, the control unit 54 monitors whether the detection signal output from the position sensor 40 is turned on (S38). Then, when the detection signal output from the position sensor 40 turns ON (YES in S38), the control unit 54 stops driving the drive device (20, 22) in the normal rotation direction, and causes the processing table 30 to rotate in the normal rotation direction. The direction rotation is stopped (S40).

FIG. 14 is a timing chart showing changes in the state of the stop signal, the state of the drive device (20, 22), and the state of the detection signal from the position sensor 40 when the control unit 54 executes the above-described stop processing. It is. As shown in FIG. 14, the drive device (20, 22) rotates the processing table 30 in the normal rotation direction at a speed V1. In this state, even if a stop signal is output from the production control device 60, the drive devices (20, 22) rotate the processing table 30 in the normal rotation direction at the speed V1. Then, when the detection signal from the position sensor 40 turns ON, the normal rotation of the processing table 30 is stopped. At this time, the detection signal from the position sensor 40 remains ON. Next, the drive device (20, 22) rotates the processing table 30 in the reverse direction at a speed V1, and when the detection signal from the position sensor 40 turns OFF, stops the rotation of the processing table 30 in the reverse direction. Next, the processing table 30 rotates in the forward direction at a speed V2 smaller than the speed V1, and when the detection signal from the position sensor 40 turns ON, the forward rotation of the processing table 30 is stopped.

In the heat treatment furnace system of the second embodiment as well, the rotation of the processing table 30 is stopped from a state in which the processing table 30 is being rotated at a constant speed V2 that is unrelated to the type of heat treatment. Further, the rotation speed V2 of the processing table 30 is set to a smaller value than the rotation speed V1 during heat treatment. Therefore, the processing table 30 can be accurately stopped at a preset position (angular position). Thereby, the work of attaching the processing table 30 to the heat treatment furnace main body 10 can be facilitated.

Although specific examples of the technology disclosed in this specification have been described above in detail, these are merely illustrative and do not limit the scope of the claims. The techniques described in the claims include various modifications and changes to the specific examples illustrated above. Further, the technical elements described in this specification or the drawings exhibit technical usefulness singly or in various combinations, and are not limited to the combinations described in the claims as filed.

100 Heat treatment furnace system A Loading area B Loading and unloading area W Workpiece 10 Heat treatment furnace 11 Furnace body 12 Ceiling wall 14 Side wall 16 Frame 18 Elevating floor 20 Drive mechanism 22 Drive device 24 Elevating device 26 Furnace space 28 Opening 30 Processing table 32 Large Diameter portion 33 Small diameter portion 34 Main hearth 36 Secondary hearth 38 Dog 40 Position sensor 42 Second drive shaft 44 Second connection portion 46 First connection portion 48 Support plate 50 Heater 52 Gas supply device 54 Control unit 70 Transport truck

Claims (5)

A furnace body including a ceiling wall, a side wall, and an elevating floor;
a processing table that is rotatably arranged with respect to the elevating floor and on which a workpiece can be placed;
a drive device provided on the elevating floor, to which the processing table is detachably connected, and for rotationally driving the processing table;
a position sensor that detects the rotational position of the processing table with respect to the elevating floor;
a control device that controls the drive device based on the detection result of the position sensor;
It is equipped with
The processing table is
a first rotary table that has a circular shape when viewed from above and is configured to be rotatable around a first axis extending vertically through the center;
at least one second rotary table that is arranged inside the first rotary table when viewed in plan and configured to be rotatable around a second axis that extends vertically through the center thereof; It is equipped with
When viewed in plan, the center position of the second rotary table is at a different position from the center position of the first rotary table,
The elevating floor is movable between a first position where the lower end of the side wall is open and a second position where the lower end of the side wall is closed.
When the elevating floor is located at the first position, the processing table can be attached to and detached from the drive device,
When the elevating floor is located at the second position with the processing table connected to the drive device, the upper surface of the first rotary table and the upper surface of the second rotary table are exposed in the furnace body. Ori,
The drive device is
a first drive unit that is arranged on the first axis and rotationally drives the first rotary table;
a second drive unit that is arranged on the second axis and rotationally drives the second rotary table;
It is equipped with
The position sensor outputs a detection signal when the first rotary table is within a preset angle range with respect to the elevating floor;
The control device includes:
When stopping the rotation of the first rotary table from a state where the first rotary table is rotating at a first speed in a first rotation direction,
(1) When the detection signal is output from the position sensor, the first rotary table further rotates in the first rotation direction while the detection signal is being output, and the output detection signal stops. , stopping the first rotary table;
(2) After the above (1), the first rotary table is rotated in a second rotation direction opposite to the first rotation direction at a second speed lower than the first speed. rotate it,
(3) A batch heat treatment furnace configured to stop the first rotary table when the detection signal is output from the position sensor in the state of (2). A furnace body including a ceiling wall, a side wall, and an elevating floor;
a processing table that is rotatably arranged with respect to the elevating floor and on which a workpiece can be placed;
a drive device provided on the elevating floor, to which the processing table is detachably connected, and for rotationally driving the processing table;
a position sensor that detects the rotational position of the processing table with respect to the elevating floor;
a control device that controls the drive device based on the detection result of the position sensor;
It is equipped with
The processing table is
a first rotary table that has a circular shape when viewed from above and is configured to be rotatable around a first axis extending vertically through the center;
at least one second rotary table that is arranged inside the first rotary table when viewed in plan and configured to be rotatable around a second axis that extends vertically through the center thereof; It is equipped with
When viewed in plan, the center position of the second rotary table is at a different position from the center position of the first rotary table,
The elevating floor is movable between a first position where the lower end of the side wall is open and a second position where the lower end of the side wall is closed.
When the elevating floor is located at the first position, the processing table can be attached to and detached from the drive device,
When the elevating floor is located at the second position with the processing table connected to the drive device, the upper surface of the first rotary table and the upper surface of the second rotary table are exposed in the furnace body. Ori,
The drive device is
a first drive unit that is arranged on the first axis and rotationally drives the first rotary table;
a second drive unit that is arranged on the second axis and rotationally drives the second rotary table;
It is equipped with
The position sensor outputs a detection signal when the first rotary table is within a preset angle range with respect to the elevating floor;
The control device includes:
When stopping the rotation of the first rotary table from a state where the first rotary table is rotating at a first speed in a first rotation direction,
(1) When the detection signal is output from the position sensor, the first rotary table is stopped within the set angle range;
(2) After the above (1), rotating the first rotary table in a second direction opposite to the first rotation direction,
(3) When the detection signal output from the position sensor stops in the state of (2), stopping the first rotary table;
(4) After (3), the first rotary table is rotated in the first rotation direction at a second speed that is lower than the first speed;
(5) A batch heat treatment furnace configured to stop the first rotary table when the detection signal is output from the position sensor in the state of (4). The processing table includes a plurality of the second rotary tables,
The batch heat treatment furnace according to claim 1 or 2, wherein the plurality of second rotary tables are arranged at different positions of the first rotary table without interfering with each other when viewed in plan. Multiple batch heat treatment furnace bodies,
At least one processing table according to claim 1 or 2, which is removably attached to each of the plurality of batch heat treatment furnace bodies,
A heat treatment furnace system, wherein each of the plurality of batch type heat treatment furnace bodies includes the furnace body, drive device, position sensor, and control device according to claim 1 or 2. The heat treatment furnace system according to claim 4, further comprising a transport vehicle for transporting the processing table to each of the plurality of batch type heat treatment furnace bodies.

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