Heat processing apparatus

Abstract

To simplify a device configuration regarding an apparatus capable of performing heat processing by heating a workpiece in an atmosphere including superheated water vapor.SOLUTION: A heat processing apparatus 1 includes: a heating chamber 11 where a workpiece W is arranged; and a heater 26 provided in the heating chamber 11 to heat an atmosphere in the heating chamber 11. Into the heating chamber 11, atmospheric gas constituted as gas including at least one of inert gas and air is introduced, and a smaller amount of saturated water vapor than that of the atmospheric gas is introduced. The heater 26 heats the atmospheric gas and the saturated water vapor introduced into the heating chamber 11 and converts the saturated water vapor into superheated water vapor by heating the saturated water vapor introduced into the heating chamber 11.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a heat treatment apparatus that heats a workpiece with an atmosphere containing superheated steam to perform heat treatment of the workpiece.

Background Art

[0002] As a heat treatment apparatus that heats a workpiece with an atmosphere containing superheated steam to perform heat treatment of the workpiece, for example, a heat treatment apparatus 1 disclosed in Patent Document 1 is known. In the heat treatment apparatus 1 disclosed in Patent Document 1, in a housing 2 provided with a workpiece area 4 where a workpiece is disposed, the workpiece is heated and heat-treated with an atmosphere containing superheated steam. A housing 2 is connected to an introduction pipe for introducing superheated steam generated outside the housing 2, and superheated steam is supplied from the introduction pipe into the housing 2.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the heat treatment apparatus 1 of Patent Document 1, superheated steam generated outside the housing 2 is introduced into the housing 2. For this reason, a device configuration for generating superheated steam to be introduced into the housing 2 outside the housing 2 is required, leading to a complication of the device configuration.

[0005] The present invention relates to an apparatus capable of heating a workpiece with an atmosphere containing superheated steam to perform heat treatment, and aims to simplify the apparatus configuration.

Means for Solving the Problems

[0006] (1) To solve the above problems, a heat treatment apparatus of the present invention is a heat treatment apparatus that heats a workpiece with an atmosphere containing superheated steam to perform heat treatment on the workpiece, and includes a heating chamber in which the workpiece is disposed, and a heater provided in the heating chamber to heat the atmosphere in the heating chamber. The heating chamber is configured such that an atmospheric gas composed of at least one of an inert gas and air is introduced, and a small amount of saturated steam less than the atmospheric gas is introduced. The heater is configured to heat the atmospheric gas and the saturated steam introduced into the heating chamber, and to heat the saturated steam introduced into the heating chamber to convert the saturated steam into superheated steam.

[0007] (2) In the heat treatment apparatus, the workpiece is a ceramic part.

[0008] (3) The heat treatment apparatus further includes a heater unit that is detachably attached to the heating chamber and includes the heater. The heater unit is connected to a saturated steam supply pipe for supplying the saturated steam introduced into the heating chamber to the heating chamber.

[0009] (4) In the heat treatment apparatus, a saturated steam supply pipe for supplying the saturated steam introduced into the heating chamber to the heating chamber extends to a heater arrangement region in the heating chamber where the heater is disposed, and the saturated steam is supplied from the saturated steam supply pipe into the heating chamber in the heater arrangement region.

[0010] (5) In the heat treatment apparatus, a saturated steam supply pipe for supplying the saturated steam introduced into the heating chamber to the heating chamber is provided to extend in the heating chamber, and the saturated steam is supplied in the heating chamber.

Advantages of the Invention

[0011] According to the present invention, with respect to an apparatus capable of heating a workpiece with an atmosphere containing superheated steam to perform heat treatment, simplification of the apparatus configuration can be achieved.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The present invention can be widely applied to various uses as a heat treatment apparatus that heats a workpiece by an atmosphere containing superheated steam to perform heat treatment of the workpiece. Hereinafter, heat treatment apparatuses according to the first embodiment and the second embodiment of the present invention will be described. In the following description, as indicated by double-headed arrows X1, double-headed arrows X2, and double-headed arrows X3 in FIGS. 1 to 4 described later, the vertical direction X1, the front-rear direction X2, and the left-right direction X3 in the heat treatment apparatus are defined. The vertical direction X1 is defined based on the vertical direction. The front-rear direction X2 is a direction extending in the horizontal direction, which is a direction perpendicular to the vertical direction X1, and is defined, for example, as the direction in which the workpiece is carried in and out in the heat treatment apparatus. The left-right direction X3 is defined as a direction perpendicular to both the vertical direction X1 and the front-rear direction X2.

[0014] [First Embodiment] FIG. 1 is a diagram schematically showing a heat treatment apparatus 1 according to a first embodiment of the present invention, and is a plan view including a cross section of a heating chamber 11 of the heat treatment apparatus 1. FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1, and shows a state of the heating chamber 11 as viewed from the front side. Referring to FIGS. 1 and 2, the heat treatment apparatus 1 includes a heating chamber 11, a heater unit 12, a fan 13, an atmospheric gas supply pipe 14, a saturated steam supply pipe 15, and the like. Further, in the heat treatment apparatus 1 of the present embodiment, a nitrogen tank 16, a steam generator 17, a controller 18, a temperature sensor 19, and the like are provided. The work W to be heat-treated by the heat treatment apparatus 1 is, for example, a ceramic component, such as a ceramic electronic component or a mechanical component. Further, the work W as a ceramic electronic component is, for example, a multilayer ceramic capacitor or the like.

[0015] The heating chamber 11 constitutes a chamber in which the work W is carried in and arranged inside. And the heating chamber 11 is configured to heat the work W arranged inside by an atmosphere containing superheated steam. The heating chamber 11 is configured as a rectangular parallelepiped chamber, and includes a ceiling wall 20a and a bottom wall 20b arranged on both sides in the vertical direction X1, a front wall 20c and a rear wall 20d arranged on both sides in the front-rear direction X2, and a right side wall 20e and a left side wall 20f arranged on both sides in the left-right direction X3 as chamber walls. Further, an opening is provided in the front wall 20c of the heating chamber 11, and a door 21 for opening and closing the opening of the front wall 20c is provided on the front wall 20c. The door 21 is configured as a hinged door. With the door 21 opened, the work W is carried into the heating chamber 11, or the work W is carried out of the heating chamber 11.

[0016] The heating chamber 11 is configured such that an atmospheric gas composed of at least one of an inert gas and air is introduced, and a small amount of saturated water vapor less than the atmospheric gas is introduced. In the present embodiment, the heating chamber 11 is configured such that nitrogen gas as an inert gas is introduced as the atmospheric gas, and a small amount of saturated water vapor less than the nitrogen gas is introduced. The atmosphere in the heating chamber 11 is constituted by the atmospheric gas and the saturated water vapor introduced into the heating chamber 11. Note that air may be introduced into the heating chamber 11 as the atmospheric gas. Further, a mixed gas of an inert gas and air may be introduced into the heating chamber 11 as the atmospheric gas. Further, as the atmospheric gas, an inert gas other than nitrogen gas may be introduced into the heating chamber 11. For example, argon gas may be introduced as the atmospheric gas.

[0017] The heating chamber 11 is connected via a nitrogen tank 16, which is a supply source of nitrogen gas as the atmospheric gas, and an atmospheric gas supply pipe 14. In the present embodiment, the atmospheric gas is constituted by nitrogen gas, and the nitrogen tank 16 is configured as a supply source of the atmospheric gas. The atmospheric gas supply pipe 14 penetrates the chamber wall of the heating chamber 11 and communicates with the inside of the heating chamber 11. Note that in the present embodiment, the atmospheric gas supply pipe 14 penetrates the rear wall 20d of the chamber wall of the heating chamber 11 and communicates with the inside of the heating chamber 11.

[0018] In the heat treatment apparatus 1, the atmospheric gas as nitrogen gas is supplied from the nitrogen tank 16 to the inside of the heating chamber 11 via the atmospheric gas supply pipe 14. The supply of the atmospheric gas from the nitrogen tank 16 to the heating chamber 11 via the atmospheric gas supply pipe 14 is controlled by the controller 18. The controller 18 is configured to control the supply amount of the inert gas to the heating chamber 11 by controlling the operation of a flow rate adjustment valve 22 provided in the atmospheric gas supply pipe 14, which is a supply path of the atmospheric gas from the nitrogen tank 16 to the heating chamber 11.

[0019] The heating chamber 11 is connected via a saturated steam supply pipe 15 to a steam generator 17 which is a source of saturated steam. The steam generator 17 is equipped with a boiler (not shown) and heats water to boiling based on a command from a controller 18 to generate saturated steam. The saturated steam supply pipe 15 is provided as a supply path for supplying the saturated steam introduced into the heating chamber 11 from the steam generator 17 to the heating chamber 11. The saturated steam supply pipe 15 is connected to a heater unit 12 attached to the heating chamber 11 and communicates with the interior of the heating chamber 11.

[0020] In the heat treatment apparatus 1, saturated steam is supplied from the steam generator 17 into the interior of the heating chamber 11 via the saturated steam supply pipe 15. The supply of saturated steam from the steam generator 17 to the heating chamber 11 via the saturated steam supply pipe 15 is controlled by the controller 18. The controller 18 is configured to control the supply amount of saturated steam to the heating chamber 11 by controlling the operation of a flow rate adjustment valve 23 provided in the saturated steam supply pipe 15 which is a supply path of the saturated steam from the steam generator 17 to the heating chamber 11.

[0021] In the heat treatment apparatus 1, an atmosphere gas composed of nitrogen gas and saturated water vapor are introduced into the heating chamber 11. And in the heat treatment apparatus 1, the saturated water vapor introduced into the heating chamber 11 is set to be less in amount than the atmosphere gas introduced into the heating chamber 11. In the heat treatment apparatus 1, the operation of the flow rate adjustment valve 22 provided in the atmosphere gas supply pipe 14 and the operation of the flow rate adjustment valve 23 provided in the saturated water vapor supply pipe 15 are controlled by the controller 18, so that the volume flow rate of the atmosphere gas flowing through the atmosphere gas supply pipe 14 and introduced into the heating chamber 11 and the volume flow rate of the saturated water vapor flowing through the saturated water vapor supply pipe 15 and introduced into the heating chamber 11 are controlled. And in the heat treatment apparatus 1, the supply amounts of the atmosphere gas and the saturated water vapor introduced into the heating chamber 11 are set so that the volume flow rate of the saturated water vapor flowing through the saturated water vapor supply pipe 15 and introduced into the heating chamber 11 is less than the volume flow rate of the atmosphere gas flowing through the atmosphere gas supply pipe 14 and introduced into the heating chamber 11. Thereby, less saturated water vapor than the atmosphere gas is introduced into the heating chamber 11. Note that in the heat treatment apparatus 1, for example, the volume flow rate of the saturated water vapor flowing through the saturated water vapor supply pipe 15 and introduced into the heating chamber 11 is set to a volume flow rate about 1 / 100 of the volume flow rate of the atmosphere gas flowing through the atmosphere gas supply pipe 14 and introduced into the heating chamber 11.

[0022] Further, an exhaust pipe 24 for discharging the gas in the atmosphere of the heating chamber 11 to the outside is connected to the heating chamber 11. The exhaust pipe 24 penetrates the chamber wall of the heating chamber 11 and communicates from the inside to the outside of the heating chamber 11. In the present embodiment, the exhaust pipe 24 penetrates the right side wall 20e of the chamber wall of the heating chamber 11 and communicates from the inside to the outside of the heating chamber 11. The discharge of the gas in the atmosphere of the heating chamber 11 to the outside through the exhaust pipe 24 is controlled by the controller 18. The controller 18 controls the discharge of the gas in the atmosphere of the heating chamber 11 by controlling the operation of a valve (not shown) provided in the exhaust pipe 24. When the atmosphere gas from the nitrogen tank 16 is supplied into the heating chamber 11 and when the saturated steam from the steam generator 17 is supplied into the heating chamber 11, the gas in the atmosphere of the heating chamber 11 is discharged from the exhaust pipe 24 to prevent an excessive increase in the pressure inside the heating chamber 11.

[0023] In the heating chamber 11, adjustment plates (25a to 25d) for adjusting the flow direction of the atmosphere inside the heating chamber 11 are installed. The adjustment plates 25a and 25c are arranged on both sides in the left - right direction X3 in the heating chamber 11 and are provided so as to extend along a direction perpendicular to the left - right direction X3. The adjustment plates 25a and 25c are provided so as to extend from the bottom wall 20b to the ceiling wall 20a in the heating chamber 11. The adjustment plates 25a and 25c are configured as plates provided with a large number of through - holes on the entire surface, and are made of, for example, punching metal. Since the adjustment plates 25a and 25c are provided with a large number of through - holes, the atmosphere in the heating chamber 11 flows through the adjustment plates 25a and 25c.

[0024] Further, the adjustment plate 25a is disposed in the heating chamber 11 via a space region with respect to the left side wall 20f of the heating chamber 11, and is provided so as to extend in parallel with the left side wall 20f. The space region between the adjustment plate 25a and the left side wall 20f is configured as a space through which the atmosphere in the heating chamber 11 flows. The adjustment plate 25c is disposed in the heating chamber 11 via a space region with respect to the right side wall 20e of the heating chamber 11, and is provided so as to extend in parallel with the right side wall 20e. The space region between the adjustment plate 25c and the right side wall 20e is configured as a space through which the atmosphere in the heating chamber 11 flows.

[0025] The adjustment plates 25b and 25d are disposed on both sides in the front-rear direction X2 in the heating chamber 11, and are provided so as to extend along a direction perpendicular to the front-rear direction X2. The adjustment plates 25b and 25d are configured as flat plates without through holes. Since the adjustment plates 25b and 25d are flat plates without through holes, the atmosphere in the heating chamber 11 does not pass through the adjustment plates 25b and 25d, but flows along the adjustment plates 25b and 25d.

[0026] Further, the adjustment plate 25b is attached to the door 21 inside the door 21, and is provided so as to extend in parallel with the door 21. The adjustment plate 25d is provided in the heating chamber 11 so as to extend from the bottom wall 20b to the ceiling wall 20a. Further, the adjustment plate 25d is disposed in the heating chamber 11 via a space region with respect to the rear wall 20d of the heating chamber 11, and is provided so as to extend in parallel with the rear wall 20d. The space region between the adjustment plate 25d and the rear wall 20d is configured as a space through which the atmosphere in the heating chamber 11 flows.

[0027] In the heating chamber 11, the area surrounded by the adjusting plates (25a to 25d) constitutes the area where the workpiece W is placed. Referring to FIGS. 1 and 2, the workpiece W is carried into and placed in the heating chamber 11 in a state where a plurality of workpieces W are placed on a flat plate-like member 100 (setter) for supporting the workpiece W. The setter 100 on which the workpiece W is placed is arranged in the area inside the adjusting plates (25a to 25d) in the heating chamber 11. With the workpiece W placed on the setter 100 arranged in the heating chamber 11, the door 21 is closed, and the heat treatment of the workpiece W by the heat treatment apparatus 1 is performed. Note that the setter 100 is arranged in the heating chamber 11 in a state where, for example, a plurality of sets are stacked at a predetermined distance in the vertical direction X1. That is, the setters 100 stacked in a plurality of stages and adjacent to each other in the vertical direction X1 are arranged adjacent to each other with a predetermined distance therebetween. FIG. 2 illustrates a form in which the workpiece W is arranged in the heating chamber 11 with the workpiece W placed on each of the setters 100 stacked in four stages in the vertical direction X1. Note that the setter 100 on which the workpiece W is placed may not be stacked in a plurality of stages and may be arranged in the heating chamber 11 with only one stage.

[0028] FIG. 3 is an enlarged view showing a part of the heat treatment apparatus 1 shown in FIG. 1, and shows the heater unit 12 and the fan 13 in the heat treatment apparatus 1. Referring to FIGS. 1 and 3, the heater unit 12 is provided in the heating chamber 11 and has a heater 26 for heating the atmosphere in the heating chamber 11, and is provided as a unit that is detachably attached to the heating chamber 11. The heater unit 12 includes a heater 26 and a heater holder 27 that holds the heater 26.

[0029] The heater 26 is provided in the heater unit 12. By attaching the heater unit 12 to the heating chamber 11, the heater 26 is provided in the heating chamber 11. The heater 26 provided in the heating chamber 11 is configured to generate heat and output when energized, and heat the atmosphere flowing in the heating chamber 11. And the heater 26 is configured to heat the atmosphere gas and saturated water vapor introduced into the heating chamber 11, and heat the saturated water vapor introduced into the heating chamber 11 to make this saturated water vapor into superheated steam. Also, the heater 26 is connected to a power source (not shown), and the power supplied to the heater 26 is configured to be controlled by the controller 18.

[0030] The heater 26 has a tubular heating part 26a that generates heat when energized. And the heater 26 is provided such that the heating part 26a is disposed inside the heating chamber 11 in a state where the heater unit 12 is attached to the heating chamber 11. The heating part 26a of the heater 26 is disposed in a region between the rear wall 20d and the adjustment plate 25d in the heating chamber 11, and is provided to heat the atmosphere flowing between the rear wall 20d and the adjustment plate 25d. The tubular heating part 26a of the heater 26 is provided to extend while repeatedly reciprocating along the vertical direction X1 in the region between the rear wall 20d and the adjustment plate 25d.

[0031] The heater holder 27 is provided as a thick plate-like member that holds the heater 26 and is made of a heat insulating material. The heater holder 27 is configured to be detachably attached to the heating chamber 11. The heater holder 27 is provided to be detachably attached to the chamber wall of the heating chamber 11, and in this embodiment, is configured to be detachably attached to the rear wall 20d of the heating chamber 11.

[0032] A through hole 28 is provided in a portion of the rear wall 20d of the heating chamber 11 where the heater holder 27 is attached. The heater holder 27 is provided with a fitting portion 27a that fits into the through hole 28 provided in the rear wall 20d of the heating chamber 11, and an attachment portion 27b as a portion for being fixedly attached to the rear wall 20d. The heater holder 27 is attached to the rear wall 20d by fixing the attachment portion 27b to the rear wall 20d via a fastening member (not shown) such as a bolt with the fitting portion 27a fitted into the through hole 28 from the outside of the heating chamber 11. When the heater holder 27 is removed from the heating chamber 11, the fastening member that fixes the attachment portion 27b and the rear wall 20d is removed, and the fitting portion 27a is removed from the through hole 28 of the rear wall 20d. In this way, the heater unit 12 is configured to be detachably attached to the heating chamber 11 by the heater holder 27 holding the heater 26 being detachably attached to the rear wall 20d.

[0033] Further, the heater holder 27 is provided with a through hole 27c to which the saturated steam supply pipe 15 is connected. The saturated steam supply pipe 15 extends through the through hole 27c of the heater holder 27 and opens into the heating chamber 11 to communicate with the inside of the heating chamber 11. With this configuration, the heater unit 12 is connected to the saturated steam supply pipe 15 for supplying the saturated steam introduced into the heating chamber 11 to the heating chamber 11. The saturated steam introduced into the heating chamber 11 from the saturated steam supply pipe 15 connected to the heater holder 27 is supplied to the region where the heater 26 held by the heater holder 27 is disposed. Then, the saturated steam supplied to the region where the heater 26 is disposed is heated by the heater 26 and becomes superheated steam. Note that superheated steam is steam heated to a temperature higher than the boiling point and is dry steam at a temperature higher than the boiling point. The saturated steam supplied into the heating chamber 11 from the saturated steam supply pipe 15 becomes superheated steam by being heated by the heater 26.

[0034] Referring to FIGS. 1 and 3, the fan 13 is provided to flow the atmosphere in the heating chamber 11 and is installed in the heating chamber 11. The fan 13 is disposed in a region between the rear wall 20d and the adjustment plate 25d in the heating chamber 11 and is provided to form the flow of the atmosphere in the heating chamber 11. As the fan 13, various fans such as a centrifugal fan and an axial flow fan can be used. In the present embodiment, the fan 13 is configured as a sirocco fan. Therefore, the fan 13 is configured to suck gas from the axial direction by rotating, apply centrifugal force to the sucked gas, and send out the gas in the centrifugal direction. Further, the fan 13 is configured to be rotationally driven by a drive motor 29, and the rotation of the drive motor 29 is configured to be controlled by a controller 18.

[0035] Also, in the region between the rear wall 20d and the adjustment plate 25d in the heating chamber 11, an induction wall portion 30 for inducing the flow of the atmosphere from the heater 26 to the fan 13 is provided between the heater 26 and the fan 13. A through hole 30a for allowing gas to pass through is formed through the induction wall portion 30 at a portion corresponding to the suction port of the fan 13. When the fan 13 rotates, a flow of the atmosphere in the direction from the heater 26 side to the fan 13 side is formed. The atmosphere in the heating chamber 11 heated by the heater 26 passes through the through hole 30a of the induction wall portion 30, is sucked into the fan 13, and is sent to the downstream side by the centrifugal force applied by the fan 13.

[0036] When heat-treating the workpiece W in the heat treatment apparatus 1, the fan 13 operates to cause the atmosphere in the heating chamber 11 to circulate and flow. That is, the atmosphere in the heating chamber 11 flows in a circulating manner by the flow formed by the operation of the fan 13 within the heating chamber 11. In FIGS. 1 and 2, the flow path of the atmosphere in the heating chamber 11 is schematically shown by a plurality of dashed-dotted arrows. The atmosphere in the heating chamber 11 that flows due to the operation of the fan 13 flows along the region between the rear wall 20d and the adjustment plate 25d and is heated by the output of the heater 26. The atmosphere heated by the heater 26 is sent by the fan 13 to the region between the left side wall 20f and the adjustment plate 25a, and further passes through the adjustment plate 25a in which a large number of through holes are formed, and flows to the workpiece W placed on the setter 100. When the heated atmosphere passes through the workpiece W on the setter 100, the workpiece W is heated by the atmosphere and heat-treated. The atmosphere that has passed through the workpiece W flows through the adjustment plate 25c in which a large number of through holes are formed, flows to the fan 13, and again forms a circulating flow of the atmosphere within the heating chamber 11.

[0037] Referring to FIG. 1, the temperature sensor 19 is provided as a sensor for detecting the temperature of the atmosphere in the heating chamber 11. In the present embodiment, the temperature sensor 19 is provided so as to detect the temperature of the atmosphere in the heating chamber 11 in the region between the right side wall 20e and the adjustment plate 25c within the heating chamber 11. The temperature sensor 19 is electrically connected to the controller 18, and the detected value of the temperature of the atmosphere in the heating chamber 11 detected by the temperature sensor 19 is transmitted to the controller 18.

[0038] Referring to FIG. 1, the controller 18 is provided as a control device for controlling the operation of the heat treatment apparatus 1. The controller 18 is configured to include, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The CPU reads a program corresponding to the processing content from the ROM and expands it in the RAM, and in cooperation with the expanded program, controls the operation of the steam generator 17, the flow rate adjustment valve 23 of the saturated steam supply pipe 15, the flow rate adjustment valve 22 of the atmosphere gas supply pipe 14, the heater 26 of the heater unit 12, and the drive motor 29 that drives the fan 13 in the heat treatment apparatus 1.

[0039] Also, the controller 18 is configured to control the supply start timing of the saturated steam supplied into the heating chamber 11 based on the detected value of the atmosphere temperature received from the temperature sensor 19. When the heat treatment in the heat treatment apparatus 1 is started, first, the operation of the flow rate adjustment valve 22 of the atmosphere gas supply pipe 14 is controlled, and the supply of the atmosphere gas from the atmosphere gas supply pipe 14 to the heating chamber 11 is started. Then, the operations of the heater 26 and the fan 13 are started, and the atmosphere in the heating chamber 11 is heated while being circulated in the heating chamber 11. And when the temperature of the atmosphere detected by the temperature sensor 19 exceeds a predetermined temperature, the operation of the flow rate adjustment valve 23 of the saturated steam supply pipe 15 is controlled, and the supply of the saturated steam from the saturated steam supply pipe 15 to the heating chamber 11 is started. The predetermined temperature at which the supply of the saturated steam to the heating chamber 11 is started is set to a specific temperature higher than the temperature of the saturated steam.

[0040] [Operation of Heat Treatment Apparatus] Next, the operation of the heat treatment apparatus 1 will be described. When the processing in the heat treatment apparatus 1 is started, the work W placed on the setter 100 is carried into the heating chamber 11 and arranged therein. When the processing in the heat treatment apparatus 1 is started, first, the operation of the flow rate adjustment valve 22 provided in the atmosphere gas supply pipe 14 is controlled, and the supply of the atmosphere gas from the atmosphere gas supply pipe 14 to the heating chamber 11 is started. Also, when the processing in the heat treatment apparatus 1 is started, the operations of the heater 26 and the fan 13 are also started. By starting the operation of the fan 13, an atmosphere flow is formed so that the atmosphere in the heating chamber 11 circulates within the heating chamber 11. The atmosphere gas supplied from the atmosphere gas supply pipe 14 into the heating chamber 11 flows along the atmosphere flow formed by the fan 13 to the heater 26 and is heated by the heater 26.

[0041] The atmosphere gas supplied to the heating chamber 11 constitutes the atmosphere in the heating chamber 11 and circulates within the heating chamber 11 while being heated by the heater 26. The atmosphere in the heating chamber 11 composed of the atmosphere gas is heated while circulating within the heating chamber 11 until it rises to a predetermined temperature. Then, when the temperature of the atmosphere detected by the temperature sensor 19 exceeds the predetermined temperature, the operation of the flow rate adjustment valve 23 of the saturated steam supply pipe 15 is controlled, and the supply of saturated steam from the saturated steam supply pipe 15 connected to the heater unit 12 to the heating chamber 11 is started.

[0042] The saturated steam supplied into the heating chamber 11 from the saturated steam supply pipe 15 is supplied to the region where the heater 26 is disposed. Then, the saturated steam supplied to the region where the heater 26 is disposed is heated by the heater 26 and becomes superheated steam. The superheated steam generated by heating the saturated steam by the heater 26 flows along the atmosphere flow formed by the fan 13, passes through the adjustment plate 25a, and flows to the work W placed on the setter 100. Further, the superheated steam generated by heating the saturated steam by the heater 26 constitutes the atmosphere in the heating chamber 11 together with the atmosphere gas supplied into the heating chamber 11 and circulates in the heating chamber 11. The atmosphere composed of the atmosphere gas and the superheated steam is heated while circulating in the heating chamber 11. Then, the work W disposed in the heating chamber 11 is heated by the atmosphere composed of the atmosphere gas and the superheated steam, and the work W is heat-treated.

[0043] When the heat treatment of the work W is sufficiently performed, the supply of the saturated steam to the heating chamber 11 is stopped, and the output of the heater 26 is also stopped. Then, only the supply of the atmosphere gas composed of nitrogen gas is continued. After that, when the temperature of the atmosphere in the heating chamber 11 sufficiently decreases, the supply of the atmosphere gas to the heating chamber 11 is stopped, and the work W is carried out from the heating chamber 11.

[0044] [Operations and Effects of this Embodiment] According to this embodiment, saturated water vapor is introduced into the heating chamber 11 where the heat treatment of the work W is performed, together with the atmosphere gas configured as at least one of an inert gas and air. Then, the atmosphere gas is heated by the heater 26 provided in the heating chamber 11, and at the same time, the saturated water vapor is also heated, and the heated saturated water vapor becomes superheated steam. For this reason, in the heating chamber 11, the work W is heated and heat-treated by the atmosphere containing superheated steam. And according to this embodiment, saturated water vapor is introduced into the heating chamber 11 to generate an atmosphere containing superheated steam in the heating chamber 11. For this reason, it is only necessary to supply saturated water vapor to the heating chamber 11, and the device configuration for generating superheated steam outside the heating chamber 11 and supplying it to the heating chamber 11 can be made unnecessary. Therefore, according to this embodiment, it is possible to simplify the device configuration for a device capable of heating the work W with an atmosphere containing superheated steam and performing heat treatment.

[0045] Further, according to the present embodiment, by heating the workpiece W in an atmosphere containing superheated steam, in addition to heating the workpiece W itself for heat treatment, a degreasing treatment for hydrolyzing and removing the oil and fat components adhering to the workpiece W can be performed. Further, when the workpiece W is a sintered body to be sintered by heat treatment, the workpiece W of the sintered body is bonded with a binder containing a resin component. In this case, by heating the workpiece W in an atmosphere containing superheated steam, in addition to performing a heat treatment for heating and sintering the workpiece W itself, a debinding treatment for hydrolyzing and removing the binder can be performed. When performing the degreasing treatment or the debinding treatment together with the heat treatment of the workpiece W by heating the workpiece W in an atmosphere containing superheated steam, if the amount of superheated steam in the atmosphere in the heating chamber 11 is large, there is a risk of causing condensation in the heating chamber 11. However, in the present embodiment, in the heating chamber 11, since the saturated steam introduced in an amount smaller than the atmosphere gas composed of at least one of the inert gas and air becomes superheated steam, the amount of superheated steam in the atmosphere in the heating chamber 11 is prevented from becoming excessive. Therefore, in the present embodiment, the workpiece W can be heated in an atmosphere containing superheated steam to perform the heat treatment of the workpiece W and the degreasing treatment or the debinding treatment, and further, the occurrence of condensation in the heating chamber can be suppressed.

[0046] Further, in the present embodiment, the workpiece W is a ceramic part, and the workpiece W is provided as a sintered body to be sintered by heat treatment and is bonded with a binder containing a resin component. Therefore, according to the present embodiment, by heating the workpiece W in an atmosphere containing superheated steam, in addition to performing a heat treatment for heating and sintering the workpiece W itself, a debinding treatment for hydrolyzing and removing the binder can be performed.

[0047] Also, according to the present embodiment, a heater unit 12 having a heater 26 is detachably attached to the heating chamber 11, and a saturated steam supply pipe 15 is connected to the heater unit 12. Therefore, the mechanism for introducing saturated steam into the heater 26 and the heating chamber 11 can be maintained independently of the heating chamber 11, and the maintainability can be improved. Further, when the mechanism for introducing saturated steam into the heater 26 and the heating chamber 11 deteriorates, they can be separated from the heating chamber 11 and replaced. Also, since the saturated steam supply pipe 15 is connected to the heater unit 12, the saturated steam introduced into the heating chamber 11 from the saturated steam supply pipe 15 is supplied to the region where the heater 26 is disposed, and the saturated steam supplied into the heating chamber 11 can be quickly heated to superheated steam.

[0048] [Second Embodiment] Next, the heat treatment apparatus 2 according to the second embodiment of the present invention will be described. FIG. 4 is a diagram schematically showing the heat treatment apparatus 2 according to the second embodiment of the present invention, and is a plan view including a cross section of the heating chamber 11 of the heat treatment apparatus 2. The heat treatment apparatus 2 of the second embodiment is configured in the same manner as the heat treatment apparatus 1 of the first embodiment, but is different from the first embodiment in the configuration related to the heater 26 and the saturated steam supply pipe 15. In the following description of the second embodiment, elements having the same configuration as those in the first embodiment described above and elements configured corresponding to those in the first embodiment are denoted by the same reference numerals in the drawings or by referring to the same reference numerals, and redundant descriptions are omitted.

[0049] Referring to FIG. 4, in the heat treatment apparatus 2 according to the second embodiment, there is no heater unit 12 having a heater 26 and a heater holder 27 for holding the heater 26 and being detachably attached to the heating chamber 11. The heater 26 is provided on the rear wall 20d of the heating chamber 11. Similar to the first embodiment, the heater 26 provided in the heating chamber 11 is configured to generate heat and output by being energized, and heat the atmosphere flowing in the heating chamber 11. The heater 26 is configured to heat the atmosphere gas and saturated water vapor introduced into the heating chamber 11, and to heat the saturated water vapor introduced into the heating chamber 11 to make this saturated water vapor into superheated steam.

[0050] Similar to the first embodiment, the heater 26 has a tubular heating part 26a that generates heat when energized. The heater 26 is provided on the rear wall 20d of the heating chamber 11 such that the heating part 26a is arranged inside the heating chamber 11. The heating part 26a of the heater 26 is arranged in the region between the rear wall 20d and the adjustment plate 25d in the heating chamber 11, and is provided to heat the atmosphere flowing between the rear wall 20d and the adjustment plate 25d. The tubular heating part 26a of the heater 26 is provided to extend while repeatedly reciprocating along the vertical direction X1 in the region between the rear wall 20d and the adjustment plate 25d. In FIG. 4, the heater arrangement region 31, which is the region where the heater 26 is arranged in the heating chamber 11, is indicated by a two-dot chain line. The heating part 26a of the heater 26 arranged in the heating chamber 11 is arranged in the heater arrangement region 31.

[0051] The saturated steam supply pipe 15 for supplying the saturated steam introduced into the heating chamber 11 to the heating chamber 11 is connected to the heating chamber 11 from the right side wall 20e of the heating chamber 11 and communicates with the inside of the heating chamber 11. And the saturated steam supply pipe 15 is provided so as to penetrate the right side wall 20e and extend inside the heating chamber 11, and is configured to supply saturated steam inside the heating chamber 11. In this embodiment, the saturated steam supply pipe 15 provided so as to extend inside the heating chamber 11 is provided so as to extend from the right side wall 20e toward the heater 26 in the region between the rear wall 20d and the adjustment plate 25d inside the heating chamber 11. Further, the saturated steam supply pipe 15 extends to the heater arrangement region 31 where the heater 26 is arranged inside the heating chamber 11. The saturated steam supply pipe 15 extending from the right side wall 20e to the heater arrangement region 31 inside the heating chamber 11 opens in the heater arrangement region 31 and communicates with the inside of the heating chamber 11. For this reason, saturated steam is supplied from the saturated steam supply pipe 15 into the heating chamber 11 in the heater arrangement region 31.

[0052] In the heat treatment apparatus 2, saturated steam is supplied into the heating chamber 11 from the saturated steam supply pipe 15 extending to the heater arrangement region 31 inside the heating chamber 11 at the heater arrangement region 31. And the saturated steam supplied to the heater arrangement region 31 is heated by the heater 26 and becomes superheated steam. The superheated steam generated by heating the saturated steam by the heater 26 flows along the flow of the atmosphere formed by the fan 13, passes through the adjustment plate 25a, and flows to the work W placed on the setter 100. Also, the superheated steam generated by heating the saturated steam by the heater 26 constitutes the atmosphere inside the heating chamber 11 together with the atmosphere gas supplied into the heating chamber 11 and circulates inside the heating chamber 11. The atmosphere composed of the atmosphere gas and the superheated steam is heated while circulating inside the heating chamber 11. And the work W arranged inside the heating chamber 11 is heated by the atmosphere composed of the atmosphere gas and the superheated steam, and heat treatment is performed on the work W.

[0053] According to the heat treatment apparatus 2 of the second embodiment, regarding an apparatus capable of performing heat treatment by heating a workpiece W with an atmosphere containing superheated steam, similar to the first embodiment, simplification of the apparatus configuration can be achieved. And according to the heat treatment apparatus 2 of the second embodiment, the saturated steam supply pipe 15 extends to the heater arrangement region 31 in the heating chamber 11 and supplies saturated steam into the heating chamber 11 at the heater arrangement region 31. For this reason, the saturated steam supplied into the heating chamber 11 from the saturated steam supply pipe 15 can be quickly heated to superheated steam. Further, according to the heat treatment apparatus 2 of the second embodiment, the saturated steam supply pipe 15 is provided so as to extend in the heating chamber 11 and supplies saturated steam into the heating chamber 11. For this reason, since the saturated steam supply pipe 15 extending in the heating chamber 11 is heated by the atmosphere in the heating chamber 11, it is possible to suppress the temperature of the saturated steam passing through the saturated steam supply pipe 15 in the heating chamber 11 from decreasing and condensing.

[0054] [Modification Example] As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the foregoing embodiments, and can be variously modified and implemented as long as it is within the scope described in the claims. For example, the following modification examples may be implemented.

[0055] In the foregoing embodiment, in the heating chamber 11, the heater 26 and the fan 13 are illustrated as being arranged in the region between the rear wall 20d and the adjustment plate 25d, but this is not necessary. For example, the heater 26 and the fan 13 may be installed on the ceiling wall 20a of the heating chamber 11 and arranged below the ceiling wall 20a. In this case, the adjustment plate 25d that extends parallel to the rear wall 20d is not provided, and the adjustment plates 25a and 25c having a large number of through holes are provided so as to extend from the front wall 20c to the rear wall 20d. And a space region is provided between the upper ends of the adjustment plates 25a and 25c and the ceiling wall 20a, and a flat adjustment plate without through holes is provided so as to connect the upper ends of the adjustment plates 25a and 25c. The flat adjustment plate connecting the upper ends of the adjustment plates 25a and 25c is arranged with respect to the ceiling wall 20a via the space region and is provided so as to extend parallel to the ceiling wall 20a. The heater 26 and the fan 13 are arranged in the region between the flat adjustment plate parallel to the ceiling wall 20a and the ceiling wall 20a. In this form, the atmosphere heated by the heater 26 arranged on the ceiling wall 20a side flows through the adjustment plate 25a to the work W placed on the setter 100 by the flow of the atmosphere formed by the fan 13, and further flows upward through the adjustment plate 25c. Then, it flows along the ceiling wall 20a, flows to the fan 13, and a flow of the atmosphere circulating in the heating chamber 11 is formed again.

[0056] Further, in the foregoing embodiment, the fan 13 is configured as a sirocco fan, and the form in which the induction wall portion 30 for inducing the flow of the atmosphere is provided between the fan 13 and the heater 26 is illustrated, but this is not necessary. The fan 13 may be provided as an axial flow fan such as a propeller fan, and the form in which the induction wall portion 30 is not provided may be implemented. In this case, the fan 13 as an axial flow fan and the heater 26 are arranged in the region between the rear wall 20d and the adjustment plate 25d. Then, by the operation of the fan 13 as an axial flow fan, a flow of the atmosphere heated by the heater 26 circulating in the heating chamber 11 is formed.

Industrial Applicability

[0057] The present invention can be widely applied as a heat treatment apparatus that heats a workpiece by an atmosphere containing superheated steam to perform heat treatment of the workpiece.

Explanation of Signs

[0058] 1, 2 Heat treatment apparatus 11 Heating chamber 12 Heater unit 13 Fan 14 Atmosphere gas supply pipe 15 Saturated steam supply pipe 16 Nitrogen tank 17 Steam generator 18 Controller 26 Heater

Claims

1. A heat treatment apparatus for heating a workpiece by an atmosphere containing superheated steam to perform heat treatment on the workpiece, comprising: a heating chamber in which the workpiece is disposed; and a heater provided in the heating chamber for heating the atmosphere in the heating chamber. The heating chamber is configured such that an atmosphere gas composed of at least one of an inert gas and air is introduced, and a smaller amount of saturated steam than the atmosphere gas is introduced. The heater is configured to heat the atmosphere gas and the saturated steam introduced into the heating chamber, and to heat the saturated steam introduced into the heating chamber to convert the saturated steam into superheated steam. A heat treatment apparatus characterized by this.

2. The heat treatment apparatus according to Claim 1, wherein the workpiece is a ceramic part. A heat treatment apparatus characterized by this.

3. The heat treatment apparatus according to Claim 1 or Claim 2, further comprising a heater unit including the heater and detachably attached to the heating chamber, wherein the heater unit is connected to a saturated steam supply pipe for supplying the saturated steam introduced into the heating chamber to the heating chamber. A heat treatment apparatus characterized by this.

4. The heat treatment apparatus according to Claim 1 or Claim 2, wherein a saturated steam supply pipe for supplying the saturated steam introduced into the heating chamber to the heating chamber extends to a heater arrangement region in the heating chamber where the heater is arranged, and the saturated steam is supplied from the saturated steam supply pipe into the heating chamber in the heater arrangement region. A heat treatment apparatus characterized by this.

5. The heat treatment apparatus according to Claim 1 or Claim 2, wherein a saturated steam supply pipe for supplying the saturated steam introduced into the heating chamber to the heating chamber is provided to extend in the heating chamber, and the saturated steam is supplied in the heating chamber. A heat treatment apparatus characterized by this.

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