JP2001199528A - Lifter having gas floating means, heat treatment device, and heat treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lifter for preventing dust from being generated caused by the friction of an object with a conveying means, in a lifter to be used for adjusting the position of the object in the stage direction, in a heat treatment device formed by providing plural stages of heat treatment zones. SOLUTION: The lifter including a loading means capable of loading an object, for changing the position of the object in the direction perpendicular to the conveying direction of the object by the movement of one or plural arms connected to the loading means, and having a means for floating the object from the loading means is incorporated in a heat treatment device formed by providing plural stages of heat treatment zones, and the movement of the object between the lifter and the heat treatment zones is performed in a state where the object is floated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment apparatus used for manufacturing, for example, a plasma display panel (PDP) or a solar cell panel, wherein a plurality of heat treatment zones are provided in a vertical direction. The present invention relates to a lifter used for moving an object from step to step, a heat treatment apparatus including the lifter, and a heat treatment method using the heat treatment apparatus.

[0002]

2. Description of the Related Art Various heat treatments, such as heating and cooling, are used in the production process of various products. Specifically, drying, baking, sealing, exhausting, annealing,
Many other effects achieved by heat treatment are known.

For example, in order to improve the productivity of heat treatment, it has been proposed to carry out heat treatment by passing an object through a dome-shaped or tunnel-shaped heating furnace while conveying the object on a mesh belt conveyor, a roller hearth or the like. ing.

FIG. 7 is a perspective view schematically showing a mesh belt transport type heat treatment apparatus using electric resistance heating, which is generally used for manufacturing electronic parts and the like. Heat treatment equipment (100)
In the example, the mesh belt (106) continuously moves in one direction in a tunnel formed of a metal material called a heating muffle (104) surrounded by an electric resistance heater block (102). The object (108) to be heat-treated is placed on the mesh belt (106) and supplied to the supply unit (loader).
It moves from the (110) side to the discharge unit (unloader) (112) side. The object (108) is heated at a predetermined temperature while passing through the heating muffle (104). Mesh belt (10
6) and the object (108) pass through the zone surrounded by the heater block (102) and are cooled while passing through the cooling muffle (116) provided with the cooling water pipe (114).

[0005] The heating furnace used for heat treatment is generally
A heating zone (also referred to as a heating zone or a sintering zone) for heating and raising the temperature of the object along the transport direction of the object, a constant temperature zone for maintaining a constant temperature of the heated object, A heat treatment zone in which a cooling zone for cooling and lowering the temperature (also referred to as a slow cooling zone, a rapid cooling zone, or a cooling zone) is arranged, and a predetermined heat treatment is performed while the object sequentially passes through each zone. It has become so. Usually, heat is applied in the temperature raising zone, heat is added in an amount corresponding to the amount of heat radiation in the constant temperature zone, and heat is taken away in the temperature lowering zone.

[0006] The heating furnace used for the heat treatment is as follows.
A one-stage type in which a temperature raising zone, a constant temperature zone, and a temperature lowering zone are provided on a straight line is generally used. However, recently, in order to reduce the installation space of the heating furnace, for example, two sets of roller hearths are installed vertically in one heating furnace, and a part of the heating zone and the cooling zone are provided on the upper roller hearth, A heating furnace provided with a cooling zone on a roller hearth, that is, a two-stage heating furnace in which a heat treatment zone is divided into two stages has been proposed (Yoshige Shimozato, "Firing Furnace for PDP", Electronic Materials December 1997 See pages 69-72). In such a two-stage heating furnace, the object is heat-treated in the upper stage, moved to the lower stage, and heat-treated in the lower stage. Therefore, in a two-stage heating furnace, it is necessary to provide a device for moving an object from an upper stage to a lower stage, and the device is called a lifter (or an elevator).

[0007] The lifter includes means for placing the object which has passed through the heat treatment zone, and the means can be moved up and down by appropriate means. In general, the placing means is constituted by a roller hearth continuous from the heat treatment zone so that the object can be moved to a predetermined position on the placing means. The roller hearth is driven by a suitable driving means.

[0008]

When the lifter having the above structure is used, when the heat-treated object is moved to the roller hearth on the lift side, the object or the object is placed in a carrier tray (for example, a glass tray) or the like. When the transport member is carried by the transport member, the transport member comes into contact with the roller hearth on the lift side, and friction is generated between the two by the drive of the roller hearth, and as a result, dust is generated from the object or the transport member. There is. The generation of dust causes damage to the heat-treated portion of the target object and hinders proper heat treatment at the portion, thereby lowering the yield. Further, for example, dust adhering between the conductive patterns on the PDP substrate causes an unfavorable effect on the product after the heat treatment, such as causing a short circuit. The generation of dust is particularly remarkable when an object or a transport member heated to a high temperature by heat treatment is rubbed with a roller hearth or the like. It is considered that this is because the object heated to high temperature is easily softened and worn.
Further, when an oxide film is formed on the surface of the object, the oxide film protects the surface of the object from abrasion until a predetermined temperature, but when heated to a predetermined temperature or higher, the protective effect of the oxide film is reduced. It is believed that the oxide film is lost, and the oxide film and the part under the oxide film are rapidly worn, and dust is also likely to be generated.

As a means for avoiding such a problem, there is a method of lowering the temperature of the object or the tray before moving to the lifter. However, depending on the temperature profile to be obtained during the heat treatment, it may not be possible to lower the temperature of the object before the lifter. Further, even when the temperature of the object is lowered, the object or the conveying member and the roller hearth are still in contact with each other, thereby generating some dust. That is, there is a limit in suppressing the generation of dust by controlling the temperature of the target object.

The present invention has been made in view of the above circumstances, and in a heat treatment apparatus having a heat treatment zone divided into a plurality of stages, an object is moved to a heat treatment zone of a different stage by a lifter without generating dust. This was done as an issue.

[0011] In this specification, "heat treatment" means
The process of raising the temperature of the target, constant temperature, lowering the temperature or a combination thereof, and raising, lowering or maintaining the temperature of the target, or a process of any combination of these may be performed. The process may be any of applying heat to or removing heat from the object, or any combination of these (and possibly including thermal insulation). By this heat treatment, at least one property of the object (for example, moisture retention, weight, electric resistance, transmittance, formed film thickness or its uniformity, internal stress or strain, strength, composition, etc.) changes as predetermined. I do.

For example, a process of applying heat to an object includes a process of raising the temperature of the object to a predetermined temperature for a predetermined time,
The process includes a process of maintaining the temperature of the target at a predetermined temperature for a predetermined time and a process of exposing the target to a predetermined temperature change condition. In addition, the process of removing heat from the object is performed when no heat is applied, that is, by a method of natural cooling, or by blowing cold air by power, or by absorbing heat that can be controlled to a predetermined temperature or radiating heat. The method includes a process of lowering the temperature of the target object by a method using forced cooling using a surface or the like.

[0013]

SUMMARY OF THE INVENTION In a first aspect, the present invention includes a mounting means on which an object can be mounted, the object being moved by one or more arms connected to the mounting means. A lifter for changing the position of the target object in a direction perpendicular to the transport direction of the target object, the lifter including means for floating the target object from the mounting means. The means for causing the object to float from the arm includes, specifically, (1) gas discharging means for applying a levitation force for floating the object and blowing gas to a part of the object, and (2) gas discharging means. It is preferable to use gas levitation means having a gas supply means for supplying gas to the air.

The "lifter" of the present invention changes the position of an object in a direction perpendicular to the direction in which the object is transported. Here, the “transport direction” of the object refers to a direction in which the object is moved when the object is subjected to predetermined processing or processing, preferably heat treatment,
Usually in the horizontal direction. When the transport direction is the horizontal direction, the moving direction of the target object in the lifter is the vertical direction.

The term "object" refers to an object which is conveyed into a zone where processing or processing is performed in order to perform predetermined processing or processing. It is particularly preferred to use the lifter of the present invention in combination with a heat treatment device, as described below, so that the object is particularly preferably conveyed into a heat treatment zone for heat treatment. The object is
For example, it may be of various substrates, especially plates or sheets. In addition, the object has, as a part thereof, a surface on which the gas discharged from the gas levitation means is blown and a levitation force acts. When the object is carried on a carrier such as a carrier tray, the object is carried together with the carrier, subjected to heat treatment in a heat treatment zone on the carrier, and the carrier is levitated. Levitate by Therefore, in the present specification, unless otherwise specified, to transport, heat-treat, and levitate an object, a transport member such as a carrier tray carrying the object is transported and subjected to heat treatment. Levitation shall also be included.

The "mounting means" is a portion on which an object is mounted, and is connected to an arm which can move in a direction perpendicular to the direction in which the object is transported. It is preferable that the mounting means can stably mount the object, and specifically, it may be a plate, a lattice, or a frame.

Alternatively, the arm itself may constitute the mounting means. In that case, it is preferable that the arm has a sufficient length for mounting the object, and a plurality of arms are provided so that the object can be stably mounted. The arms are preferably arranged evenly so that the object does not tilt when the object is levitated. For example, when the mounting means is composed of two arms, the two arms are Is preferably arranged at a position where the is divided into three equal parts.

The gas levitation means for levitating an object from the mounting means of the lifter comprises gas discharge means and gas supply means. The gas discharging means blows a gas to a part of the object. When a gas is blown on a part of the object, a levitation force for floating the object is applied to the object, and the object is levitated from the mounting means by the buoyancy force. The gas supply means supplies gas to the gas discharge means. The gas is supplied while being adjusted to an appropriate pressure in accordance with the type of the object and the degree of levitation (that is, the distance between the surface of the object on which the gas is blown and the mounting means).

The gas levitation means is, specifically, a plurality of nozzles capable of blowing gas in a predetermined direction to an object (preferably, a direction perpendicular to a surface of the object to which gas is blown). Alternatively, the lifter can be provided in the lifter by providing the opening as a gas discharging means in the arm or the mounting means, and connecting the nozzle or the opening to the gas supply means.

[0020] The lifter of the present invention having the above structure is
In combination with a specific transporting means described below, the heat-treated object can be arranged above the placing means in a state of being levitated from the placing means, and the object can be maintained while being levitated. Can also be moved within the lifter. Therefore, according to the lifter of the present invention, the object or the transporting member can be moved to the lifter without being rubbed with the constituent members of the lifter, so that generation of dust can be effectively prevented.

According to a second aspect of the present invention, there is provided a heat treatment apparatus comprising a conveying means for conveying an object, a means for heat-treating the object to be conveyed, and the lifter according to the first aspect of the present invention. A heat treatment zone for heat-treating the object is provided so as to have a plurality of stages in a direction substantially perpendicular to the transport direction of the object, and a gas for floating the object in at least a part of the heat treatment zone. Levitation means is provided, and the gas levitation means is (1)
(2) gas discharge means for exerting a levitation force for levitating an object, for blowing gas to a part of the object;
In the heat treatment apparatus, the lifter is disposed adjacent to the heat treatment zone at at least one of the ends in the transport direction of the object in the heat treatment apparatus. A heat treatment apparatus is provided.

The meaning of "heat treatment" is as described above. The "heat treatment means" is a means for performing a heat treatment. For example, a heating means as an electric heater, a cooling means for blowing cool air, a heat insulating means, and the like correspond to the heat treatment means.

The "means for conveying an object" (also simply referred to as "conveying means") is a device or a jig for conveying the object, and moves the object continuously or intermittently in a predetermined direction. Means to make it work. The transport means includes, for example, a roller hearth and a belt conveyor.

In the present invention, it is preferable that the conveying means is capable of conveying the object, which has been levitated by the gas levitating means to be described later, while being levitated. Such a transport means abuts against the rear end of the object,
Further, it is preferable that the contact member be provided with a contact member that moves in the transport direction of the target object, and the target object be pushed and transported by the movement of the contact member. Here, the term "rear end" is used in the meaning of "rear end" with respect to the moving direction of the object, and accordingly, the "rear end" depends on the moving direction.
Changes position. According to this transporting means, the object is pushed out and moves, so that the transporting by the means can be called “push-type transporting”. Further, when the object is carried on a transport member such as a carrier tray, a similar contact member is brought into contact with the rear end of the transport member, and by moving the contact member, the transport member and the transport member are moved. The carried object can be moved.

In the heat treatment apparatus of the present invention, the heat treatment zones for heat-treating the object are provided in a plurality of stages in a direction substantially perpendicular to the direction of transport of the object. The heat treatment zone refers to a region where heat treatment is performed in the heat treatment apparatus. The object heat-treated in the heat treatment zone is transported from one stage to another using a lifter. Specifically, after moving the object from the heat treatment zone onto the lifter mounting means, by moving the arm to move the mounting means in a direction perpendicular to the transport direction of the object, The object is transported to a predetermined step. The lifter is disposed adjacent to the heat treatment zone on at least one of the ends in the transport direction of the object in the heat treatment apparatus.

[0026] The heat treatment apparatus of the present invention is provided with gas levitation means for levitating an object in at least a part of the heat treatment zone. The gas levitation means includes gas discharge means and gas supply means. The gas discharging means blows a gas to a part of the object. When gas is blown on a part of the object, a levitation force acts to float the object on the object, and the object is levitated by the buoyancy. The gas supply means supplies gas to the gas discharge means. The gas is supplied after being adjusted to an appropriate pressure in accordance with the type of the object and the degree of levitation (that is, the distance between the surface of the object on which the gas is blown and the upper end surface of the gas discharging means). Is done.

According to the heat treatment apparatus of the present invention, the object is
It is possible to transport, heat-treat, move to a lifter, and further move to another stage of the heat treatment zone in a floating state. That is, in the heat treatment apparatus of the present invention, the object can be heat-treated without rubbing against the members constituting the heat treatment apparatus including the lifter. Therefore, when the heat treatment apparatus of the present invention is used, the generation of dust due to friction during the heat treatment is performed. Can be substantially eliminated or greatly reduced.

According to a third aspect, the present invention is directed to a heat treatment zone for heat treating an object to be conveyed, the heat treatment zone being provided in a plurality of stages in a direction substantially perpendicular to the direction of conveyance of the object. In the heat treatment apparatus in which the movement between the steps is performed using a lifter, when moving the object between the heat treatment zone and the lifter, at least one of the movements is performed while the object is floated. A heat treatment method is provided.

When the object is moved between the heat treatment zone and the lifter, the movement is performed in a state where the object is levitated, which means that the object is levitated, that is, parallel to the transport direction of the object. The transfer of the object from the heat treatment zone to the lifter or the transfer of the target object from the lifter to the heat treatment zone while maintaining the main surface (back surface) not in contact with the components of the heat treatment apparatus and the lifter. It should be noted that the target object can be said to have been "transferred to the lifter" when it is positioned on the mounting means of the lifter so that it can move inside the lifter.

According to the heat treatment method of the present invention, in a heat treatment apparatus provided with a plurality of heat treatment zones, when the object moves between the heat treatment zone and the lifter, the object or the carrier tray, etc. The dust generated from the conveying member can be substantially eliminated or greatly reduced, whereby the quality of the heat treatment can be improved.

[0031]

Next, specific embodiments of the present invention will be described. The lifter of the present invention changes the position of the object by moving the mounting means on which the object is mounted in a direction perpendicular to the transport direction of the object by moving one or more arms. A lifter capable of floating an object on the mounting means from the mounting means.

The mounting means is a plate-like object, a grid-like object, a frame-like object, or the like on which the object or a transport member such as a carrier tray for carrying the object is stably mounted. Therefore, the dimensions and the like are determined according to the dimensions of the object or the transport member. The mounting means is preferably formed of a material having a small coefficient of thermal expansion from the viewpoint of maintaining strength at high temperatures, resistance to oxidation, and suppressing thermal deformation. The mounting means is, specifically,
For example, it is preferable to use a high nickel superalloy such as Inconel 610, ceramics, or quartz glass. When the operating temperature is lower than 400 to 600 ° C., stainless steel or the like may be used. The use of stainless steel is economically advantageous.

The mounting means is connected to the arm so as to cooperate with the arm, and the movement of the arm moves in a direction perpendicular to the direction of transport of the object, whereby the object on the mounting means moves in the direction. At a predetermined position. The arm is provided, for example, so as to be able to slide in a predetermined passage. When the transport direction of the object is the horizontal direction, the arm is moved in the vertical direction. The mounting means is connected to the arms by, for example, mounting on a plurality of arms. The mounting means may be one integrated with the arm. Further, the arm may be positioned so as to extend in a direction parallel to the transport direction of the object, or a surface parallel to the front and back surfaces of the object (that is, a surface parallel to the transport direction) (the transport direction is horizontal). In some cases (horizontal plane), it may extend perpendicular to the transport direction of the target object.

In the present invention, the arm itself may be used as the mounting means. Thereby, the configuration of the lifter becomes simpler. When the arm is used as the mounting means, it is preferable to use a long prismatic rod or narrow plate as the arm. Further, in order to stably mount the object or the transport member, it is preferable to arrange a plurality of arms. When the arm is used as the mounting means, the arm is preferably formed of a material having a small coefficient of thermal expansion from the viewpoint of maintaining strength at high temperatures, resistance to oxidation, and suppressing thermal deformation. Specifically, for example, it is preferably formed of a high nickel superalloy such as Inconel 610 or ceramics having high impact resistance such as silicon nitride or silicon carbide. The arm has a length of 0.8 to 1 which is the length of the target object (or the transfer member) in the extending direction of the arm.
It is preferred to have a length corresponding to twice the length. That is, the distance at which the arm and the object overlap in the extending direction of the arm is preferably 0.8 to 1 times the length of the object in the same direction.

The lifter is provided with a gas levitation means comprising a gas discharge means and a gas supply means, on which an object (if the object is carried on a carrier such as a carrier tray) is placed. Be able to levitate from the means.
The gas levitation means may be configured such that a small hole or a nozzle is evenly provided as a gas discharge means in the mounting means, a gas is supplied from the gas supply means to the small hole or the nozzle, and the gas is blown to the object. For example, when the mounting means is a plate-like material, it is good to provide a small hole or a nozzle over the entire plate-like material, and when the mounting means is a frame-like material,
It is preferable to provide small holes or nozzles in the entire frame. When the mounting means is a grid, gas can be blown from the eyes of the grid.

In the present invention, it is preferable that the mounting means is a plate-like object, and the gas discharge means is arranged so that the gas discharge surface coincides with the surface of the plate-like object. Here, the gas discharge surface refers to a surface in which the flow of the gas is not restricted by a specific flow path and reaches a released state. According to such an arrangement,
The gas layer can be uniformly interposed between the object and the plate-like object (mounting means) to stably float the object.

In such an arrangement, for example, a nozzle is prepared as a gas discharging means and a thickness direction is set as a mounting means so that a gas is discharged from a small hole formed in the thickness direction of the plate-like object. This can be realized by preparing a plate-like object having a small hole penetrating therethrough, and arranging both nozzles on the arm so that the nozzle end face and the small hole of the plate-like object coincide. In this case, the gas discharged from the gas discharge means is released on the surface of the plate after the flow is restricted by the small holes provided in the plate.

Alternatively, the gas floating means may be arranged such that the gas discharge surface of the gas discharge means is flush with the surface of the mounting means (the surface closer to the object). Such an arrangement has, for example, a nozzle end surface having at least one gas discharge hole from which the blowing gas is discharged, as a gas discharge means, and the nozzle end surface is at least part of its periphery and the nozzle end surface is an upper step surface. A nozzle having a step-shaped portion is prepared, and a panel having a thickness corresponding to the height of the step-shaped portion and a through opening corresponding to the nozzle end face is prepared as a mounting means, and the nozzle is positioned on the arm. This can be realized by supporting the mounting means, which is a panel, on the stepped portion around the nozzle end face.

When the mounting means is an arm, small holes or nozzles may be provided only in a portion of the arm where the object is mounted (also simply referred to as a "mounting portion"). In this case, in order to stably levitate the object, it is preferable to increase the gas discharge amount as compared with the case where a plate-like body is used as the mounting means.

In any case, the gas blown to the object is a gas inert to the object (usually, air,
Nitrogen or the like).

FIGS. 1 and 2 show an example of the lifter of the present invention.
Shown in FIG. 1 is a partially exploded perspective view of the lifter, and FIG.
It is a side view of the arm of FIG. In the embodiment shown, the mounting means is a panel (10), which is arranged on two arms (22). On the upper surface of each arm (22), a nozzle (2
4) are provided. As shown in FIG. 2, the nozzle (24) communicating with the gas flow path (25) has a cylindrical shape, has a gas discharge hole (24a) on its upper end face, and has a gas discharge hole (24a) on its lower end face. A throttle (24b) for adjusting the flow rate is provided. The nozzle (24) has a stepped portion (24c) so as to support the panel (10). The panel (10) has a thickness equal to the height of the stepped portion (24c) and has a through opening (10a) corresponding to the nozzle end face. The object is levitated on the panel (10) by the gas blown from the nozzle (24).

The arm (22) is configured to slide on a slide guide (29) by a ball screw (28) driven by a motor (26). In the embodiment shown, the arm (22) comprises a casing (4) of insulating material.
0) (only a part is shown), and an aperture (42) is formed in the casing (40) so as to provide a movement path of the arm.

As exemplified in FIG. 1, in the lifter of the present invention, the placing means is disposed in the casing to ensure the uniformity of the temperature of the object (ie, to prevent the temperature of the object from fluctuating), It is preferable from the viewpoint of reducing heat radiation from the heat treatment zone and preventing contamination of the object. The casing is preferably formed from a heat insulating material. The casing is more preferably
When the heat treatment apparatus is configured, a heat-resistant material such as heat-resistant glass, which hardly generates dust, is disposed on a surface located inside, and a heat insulating material such as ceramic fiber is disposed on a surface located outside.

The casing accommodating the mounting means has two modes. The first casing has one aperture formed on an end face opposed to the transport direction of the target object for moving the target object into and out of the lifter, and is perpendicular to the direction in which the arm extends and close to the base of the arm. The surface has the same number of apertures as the arms through which the respective arms pass. Note that "moving an object into and out of the lifter" means moving the object from a predetermined processing or processing zone to the lifter, and moving the object from the lifter to a predetermined processing or processing zone. I do. When the lifter is incorporated in a heat treatment apparatus, the object is moved from the heat treatment zone to the lifter or from the lifter to the heat treatment zone.

This casing has a form surrounding the side surface and the upper and lower surfaces of the mounting means. It is preferable that an end face of the casing facing the transport direction of the object is adjacent to a predetermined processing or processing zone (for example, a heat treatment zone). It is also preferable that the casing is attached to the arm by an appropriate means so that when the arm moves and the mounting means moves, the casing can move together with the mounting means. When a predetermined processing or processing zone (for example, a heat treatment zone) is opened by the movement of the casing, it is preferable to provide a shutter for shielding the zone in order to insulate the zone. The shutter may be mounted on either the casing or on the member forming the predetermined processing or processing zone, or may be independent. In addition, in order to prevent the air flow in the lifter from being disturbed by the movement of the lifter, it is preferable that a shutter that shields an aperture provided on an end surface of the casing facing the transport direction of the object be provided on the casing.

FIG. 3 shows an example of such a casing.
FIG. 3 shows an example of a lifter similar to the lifter shown in FIGS. 1 and 2, in which a panel (10) and an arm (22) serving as mounting means are arranged in a casing (30). . The two-dot chain line shows the state when the arm has moved downward. In the illustrated embodiment, the lifter (20) is provided adjacent to the two-stage heat treatment zones (52a, 52b) to constitute a heat treatment apparatus. The heat treatment zones (52a, 52b) are each surrounded by a heat insulator (58) and are independent of each other, and have heat treatment means (for example, heating means) (56). Heat treatment zone (52a, 52
Also in b), the gas discharge nozzle (2
A gas discharge nozzle (54) similar to 4) is provided as gas discharge means, and a panel (53) similar to the panel (10) is provided. The panel (53) has a penetrating opening corresponding to the end face of the gas discharge nozzle (54), and is arranged such that the panel surface is flush with the gas discharge surface of the nozzle (54). The object (1) can float on the panel (53) by blowing gas from the gas discharge nozzle (54). When no gas is blown, the object (1) is supported by the panel (53).

The object (1) is placed in the casing (30).
Of the object (from the heat treatment zone (52a, 52b)) to the panel (10) in the lifter on the surface facing the transfer direction (corresponding to the white arrow in the figure) and the surface adjacent to the heat treatment zone. An aperture that allows 1) to move (3
1), and an aperture (32) that penetrates the arm (22) is formed on a surface perpendicular to the direction in which the arm (22) extends and near the base of the arm. . The casing (30) is attached to the arm (22) by any suitable means (not shown).
It moves with 2).

In FIG. 3, two shutters (33a, 33
b) is attached to the heat treatment zone. The shutter is provided to shield the two heat treatment zones, and in FIG. 3, the casing is adjacent to the upper heat treatment zone (52a) and the lower heat treatment zone (52b).
Are open, the lower shutter (33b) shields the lower heat treatment zone (52b).

The second casing has one or a plurality of apertures formed on an end face opposed to the transport direction of the object to move the object into and out of the lifter. The aperture is perpendicular to the direction in which the arm extends. On the surface near the base, one or a plurality of apertures for providing a movement path of the arm are formed. That is, this casing
A space in which the mounting means can move is defined inside, and unlike the first casing described above, the space itself does not move. The meaning of “moving the object into and out of the lifter” is as described in the previous description of the first casing.

The aperture formed in the second casing for moving the object into and out of the lifter is provided in a predetermined processing or processing zone (for example, a heat treatment zone of a heat treatment apparatus).
May be provided in the same number as the zones, or as one large aperture including the entire zone. The aperture providing the movement path of the arm is provided so as to penetrate each arm and not to hinder the movement of each arm. It is preferable that the aperture providing the movement path of the arm is provided for each arm in order to sufficiently insulate the vicinity of the mounting means or the mounting portion of the arm. Alternatively, an aperture having a large size may be formed so as to provide a movement path for a plurality of arms.

FIG. 4 shows an example of the second casing. FIG.
Is a lifter similar to the lifter shown in FIG. 1 and FIG. 2, and includes a panel (10) and an arm (2) as mounting means.
2) shows an example of a lifter disposed in the casing (30). The two-dot chain line indicates the state when the arm has moved downward, and the white arrow indicates the moving direction of the object (1). In the illustrated embodiment, the lifter (20) is provided adjacent to the two-stage heat treatment zones (52a, 52b) to constitute a heat treatment apparatus. The structure of the heat treatment zones (52a, 52b) is the same as that shown in FIG. Only one aperture (41) for moving the object (1) into and out of the lifter is formed in the casing (40), and both upper and lower heat treatment zones (52a, 52b) in the aperture (41) are formed. The object (1) can be moved between the lifter and the lifter. An aperture (42) for providing a movement path of the arm (22) is formed for each arm (20) (only one is shown in the illustrated embodiment), and has an elongated shape so that the arm (20) can move up and down. (See FIG. 1).

The lifter of the present invention can move between the heat treatment zone and the lifter in a state where the object is levitated. As in the case of a conventional lifter, the lifter is provided with a transfer means (for example, The object is not sent to a predetermined position of the lifter while the object is rubbing against the roller hearth. However, when dust due to wear of the object does not occur, or when generation of dust is not a problem, the object does not need to be levitated. Transport means commonly used in
For example, a roller hearth or a conveyor belt may be provided along with the lifter.

The lifter of the present invention is for moving an object. When it is necessary to control the temperature of the object in the lifter, for example, when the object moves in the lifter, When the range of the temperature change to be performed is ± 1 to ± 3 ° C or less, it is preferable to provide an appropriate heat treatment means in the lifter. Heat treatment means
For example, it may be provided on the inner surface of the casing of the lifter.

In the above description, the lifter of the present invention is described on the assumption that the lifter of the present invention is used in a heat treatment apparatus. However, the lifter of the present invention can be naturally applied to other processing or processing apparatuses. The lifter of the present invention can be preferably used particularly for moving an object such as a silicon wafer or a substrate, for which processing in a clean environment is desired, between a plurality of processing zones while suppressing generation of dust.

Next, a heat treatment apparatus of the present invention including the lifter of the present invention will be described. The heat treatment apparatus of the present invention is provided such that the heat treatment zones for heat-treating the target are provided in a plurality of stages in a direction substantially perpendicular to the transport direction of the target. The stages are insulated by a suitable insulating material, for example a hardened ceramic fiber board which is less likely to generate dust, and the heat treatment zones of each stage are independent of each other. The heat treatment zone of each stage further includes
It may be subdivided into zones for performing a plurality of different heat treatments.

The heat treatment apparatus of the present invention is provided with a two-stage heat treatment zone, a heating zone for heating an object in at least a part of the upper heat treatment zone, and an object in at least a part of the lower heat treatment zone. It is preferable that the heating furnace has a cooling zone for cooling the heating furnace. It is preferable that the heating furnace is further provided with a constant temperature zone for keeping the temperature of the heated object constant. In this case, the constant temperature zone is preferably provided at the end of the upper heat treatment zone and / or at the start of the lower heat treatment zone. The end and start ends of each zone are determined by the transport direction. The end portion corresponds to the portion where the transfer ends, and the start end corresponds to the portion where the transfer starts.

The heat treatment apparatus of the present invention is provided with gas floating means for floating an object at least in a part of the heat treatment zone. The gas levitation means is preferably provided at least in a heat treatment zone adjacent to the lifter in order to carry out movement of the object from the lifter to the heat treatment zone or from the heat treatment zone to the lifter while the object is levitated. Further, the gas levitation means is a combination of an appropriate support member such as a plate which will support the object if the object is not levitated, and a gas discharge means such as a nozzle, and a gas supply means to the gas discharge means. It is preferable to supply the gas from the support member so that the gas is blown to the object and floats from the support member. The preferred shapes and arrangements of the gas discharging means and the support member are the same as those of the gas discharging means and the mounting means of the lifter described above, and the specific modes thereof have been described with reference to FIG. Therefore, the detailed description is omitted here. Further, the gas suitable for blowing on the object is as described above in relation to the gas levitation means of the lifter, and a detailed description thereof will be omitted here.

It is particularly preferable that the gas levitation means be provided in the heating zone from the viewpoints of preventing generation of dust when the object is transported and abrasion of the transport member. For example, when the object is a metal and is heated so as to exceed a temperature at which the wear of the metal oxide film becomes remarkable (generally, about 400 to 600 ° C.), the object is floated by the gas levitation means. It is preferable to perform heat treatment while heating.

The means for transporting the floating object has a contact member abutting on the rear end of the object and moving along the direction of transport of the object. It is preferable that the object be pushed and conveyed by the movement. Specifically, as shown in FIG. 5A, such a transporting means is brought into contact with the rear end of the object (1) and is driven by a suitable driving means (not shown). It may be a rod (61) that pushes and transports the object (1). Alternatively, as shown in FIG. 5B, a block-like object (62) abutting the rear end at both edges of the object (1) may be used instead of the rod. The contact members may be provided at both ends of the object so that the conveying direction of the object can be quickly changed as needed. The contact member such as a rod may be connected to a continuous member (for example, a chain, a wire, or a belt) that moves by transmitting the power of a motor or the like via a roller or a gear and moved in a predetermined direction.

When a plurality of objects are arranged so as to be adjacent to each other, the abutting member is brought into contact with the rear end of the object located at the rear end in the transport direction of the objects. When the abutment member is driven, the abutment member pushes the object it is in contact with, the object pushes an adjacent object, and the adjacent object further pushes an adjacent object. The entire object is moved and conveyed by a method that can also be called a beading type, a tocorotene type, or a plug flow type.

This transporting means is described in detail in Japanese Patent Application No. 11-128537 of the present applicant, and the contents described in the application constitute a part of the present specification.

In a zone where no gas levitation means is provided, for example, in a cooling zone, the conveyance means does not need to have the above-mentioned contact means. A roller hearth or a conveyor belt may be used. This is because the object transported in the cooling zone has already been subjected to a predetermined heat treatment (for example, film formation or sintering). This is because substantially no dust is generated, and dust adhering to the object after the heat treatment can be easily removed by a later cleaning operation.

In the heat treatment apparatus of the present invention, the lifter is disposed so as to be located at at least one end of the heat treatment apparatus. For example, in the case where the object is transported and heat-treated while changing the transport direction alternately one by one in three or more heat treatment zones, the lifters need to be disposed at both ends of the heat treatment apparatus. When the heat treatment zone is provided in two stages, it is preferable that the lifter is arranged at the end of the stage of the heat treatment zone where the object is conveyed first (that is, at the front end in the conveyance direction).

The number of objects to be heat-treated in the heat treatment apparatus of the present invention is one or more, and is not particularly limited, and may be usually about 2 to 30.
A person skilled in the art can select a specific number in consideration of the type of heat treatment, productivity, equipment cost, and the like. It should be noted that the present invention does not exclude the heat treatment of one object, but it is generally inefficient to process only one object. The objects are arranged efficiently in a predetermined transport direction in the heat treatment space, are transported along the direction, and are sequentially processed by the lifter to another heat treatment zone, so that the objects are efficiently processed. You.

Although the characteristic portions of the heat treatment apparatus of the present invention have been described above, portions not described above may be constituted by commonly used materials and methods. For example, in the heating zone of the heat treatment zone, an electric heater may be adopted as a heating means,
The electric heater may be located either above or below the object, or on both sides. For example,
The heat treatment zone (52a) in FIG. 3 is an example of a heat treatment zone in which heat treatment means are arranged on both sides.

FIG. 6 shows an example of the heat treatment apparatus of the present invention. In this heat treatment apparatus (50), a heat treatment zone is provided in two stages, and an object is heated in an upper heat treatment zone (52a) and cooled in a lower heat treatment zone (52b). It has become. The moving direction of the target object in the heat treatment zone and the lifter is as indicated by a white arrow. Further, the object is blown with gas from a gas discharge nozzle (54) provided in the heat treatment zone and a gas discharge nozzle (24) provided in the lifter, so that the panel (53) in the heat treatment zone and the panel (53) in the lifter are blown. 10) It is designed to float above. In order to avoid complicating the drawing, FIG. 6 omits the object, the heat treatment means, the transport means, the casing of the lifter, and the heat insulating member provided between the steps of the heat treatment zone. .

The lifters are provided at both ends of the heat treatment apparatus. Each lifter (20A, 20B) is the same as the lifter shown in FIG. Among these, the lifter (20A) located at the start end side of the upper heat treatment zone (52) moves the object from the bottom to the upper side and moves the object upward to the upper heat treatment zone (52a).
Used to supply the arm (22
A) extends perpendicular to the transport direction. The lifter (20) located at the end of the upper heat treatment zone (52a)
B) moves the object from the upper heat treatment zone (52a) to the lower heat treatment zone (52b), and the arm (22B) extends in a direction parallel to the transport direction. In addition, the directions of the arms may be rotated by 90 °, respectively.
For example, the lifter (20B) may be arranged such that the arm (22B) is orthogonal to the transport direction.

In the embodiment shown in FIG. 6, the lifter (20A) is provided so that the object can be supplied and taken out from the lower side. However, the heat treatment apparatus of the present invention does not require such a lifter. A mechanism may be provided in which the target object is exclusively supplied from a position adjacent to the upper heat treatment zone, and the target object can be taken out at the end of the lower heat treatment zone.

Next, the heat treatment method of the present invention will be described. The heat treatment method of the present invention is a heat treatment apparatus in which a heat treatment zone for heat treating an object to be conveyed is provided in a plurality of stages in a direction substantially perpendicular to a direction in which the object is conveyed. When the object is moved from the heat treatment zone to the lifter, or when the object is moved from the lifter to the heat treatment zone, the object is moved while the object is levitated. This heat treatment method can be performed using the heat treatment apparatus of the present invention including the above-described lifter of the present invention.

In order to keep the object floating when moving the object from the heat treatment zone to the lifter, at least the heat treatment zone adjacent to the lifter needs to have gas levitation means. The gas levitation means of the lifter is operated before the object enters the lifter or at the same time as the object enters the lifter, and is arranged on the mounting means of the lifter without the members constituting the lifter rub against the object. To do.

After the object is positioned on the mounting means of the lifter, the object moves in a direction perpendicular to the direction in which the object is conveyed by the movement of the arm. In such a move,
Even if the object and the placing means are brought into contact with each other, the object and the placing means do not rub against each other (that is, the object is stationary with respect to the placing means), so that the gas floating means is operated. Instead, the object may be brought into contact with the mounting means or a gas discharge means (for example, a nozzle) provided in the mounting means.

When the object is moved from the lifter to the heat treatment zone, the object is lifted from the mounting means by the gas levitation means and then moved to the heat treatment zone. In order to move the object in a floating state, a gas floating means is provided in a heat treatment zone adjacent to the lifter,
Before or simultaneously with the movement of the object from the lifter, the gas levitation means in the heat treatment zone is operated so that the object does not rub against the members constituting the heat treatment zone.

In order to move the object in a levitated state between the heat treatment zone and the lifter, a member capable of pushing the object is brought into contact with the rear end of the object, and the contact member It is preferable that the object is pushed and moved by being driven by a suitable driving means. Such a movement can be performed, for example, using the transporting means described above with reference to FIGS. 5A and 5B.

It is particularly preferable that the object is levitated from the mounting means when the object is moved between the heat treatment zone and the lifter, when the object is at a high temperature. This is because, as described above, when the object is at a high temperature, the object or an oxide film formed on the surface of the object is easily worn, thereby easily generating dust.

In general, an object whose temperature has been lowered after firing has a high hardness, and therefore hardly generates dust even if it rubs against another member. Such an object may be moved between the heat treatment zone and the lifter without being levitated. For such movement, a conventional conveying method, for example, a conveying method using a roller hearth or a conveyor belt driven by a suitable driving means can be adopted.

[0076]

According to the lifter of the present invention described above, the object can be lifted from the mounting means when the position of the object is moved in the direction perpendicular to the direction of transport of the object. Things. Therefore, the lifter of the present invention configures the target and the lifter during the heat treatment by combining the lifter with the means for floating the target in the heat treatment zone and the heat treatment apparatus including the transporting means capable of transporting the floating target. It is possible to effectively prevent the occurrence of friction between the members and the generation of dust due to the friction. Suppression of dust provides the advantage of improving the quality and yield of the object, thereby enabling high-quality heat treatment to be performed.

[Brief description of the drawings]

FIG. 1 is a partial perspective view schematically showing an example of a lifter of the present invention.

FIG. 2 is a schematic side view of an arm of the lifter of FIG. 1;

FIG. 3 is a schematic side view of a lifter in which a mounting unit (arm) is disposed in a casing.

FIG. 4 is a schematic side view of a lifter in which a mounting means (arm) is disposed in another casing.

FIGS. 5A and 5B are schematic plan views each showing an example of a transport unit.

FIG. 6 is a schematic perspective view of a heat treatment apparatus of the present invention.

FIG. 7 is a schematic perspective view of a conventional general mesh belt conveyance type heat treatment apparatus.

[Explanation of symbols]

1 ... object, 10 ... panel, 10a ... through opening,
20,20A, 20B ... lifter, 22,22A, 2
2B ... arm, 24 ... gas discharge means, 24a ... gas discharge hole, 24b ... flow control restrictor, 24c ... step-like part, 25 ... gas flow path, 26 ... Motor, 28 ... ball screw, 29 ... slide guide, 30 ... casing, 31 ... aperture, 32 ... aperture, 33
a, 33b ... shutter, 40 ... lifter, 41 ...
Aperture, 42 ... Aperture, 50 ... Heat treatment equipment, 52a, 52b ... Heat treatment zone, 53 ... Panel,
54 ... gas discharge means, 56 ... heat treatment means, 58 ... heat insulating material, 61 ... transfer means (rod), 62 ... transfer means (block), 100 ... heat treatment apparatus, 102 ... electric resistance heater block, 104 ... heating muffle, 10
6 ... mesh belt, 108 ... object, 110 ... supply unit, 112 ... discharge unit, 114 ... cooling water pipe, 11
6. Cooling muffle.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kenji Tanimoto 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. 3F044 AA13 AB11 CA01 CA04 CF10 3F343 FA13 FB19 JB11 JD28 4K050 AA02 BA07 BA16 CA13 CD30 CF05 CF15 CG00 CG02

Claims (16)

[Claims] 1. A position of an object in a direction perpendicular to a conveying direction of the object by movement of one or a plurality of arms connected to the mounting means, the mounting means including a mounting means on which the object can be mounted. A lifter having means for floating an object from a mounting means. 2. A means for causing an object to float from the mounting means includes: (1) a gas discharging means for blowing a gas to a part of the object, which acts on a levitation force for floating the object;
2. The lifter according to claim 1, wherein the lifter has gas supply means for supplying gas to the gas discharge means. 3. A mounting means is disposed in a casing, and one aperture for moving an object into and out of a lifter is formed on an end face opposed to a direction in which the object is conveyed. The lifter according to claim 1 or claim 2, wherein the same number of apertures as the arms through which the respective arms penetrate are formed on a surface which is vertical and near the base of the arms, and the casing moves together with the arms. 4. A mounting means is disposed in a casing, and one or a plurality of apertures for moving an object into and out of a lifter are formed on an end face opposed to a direction in which the object is conveyed. The lifter according to claim 1 or 2, wherein one or more apertures are provided on a surface perpendicular to the arm and near the base of the arm to provide a movement path of the arm, and the object moves in the casing. 5. The lifter according to claim 3, wherein the casing is formed of a heat insulating material. 6. The lifter according to claim 1, wherein the mounting means is an arm. 7. A heat treatment apparatus comprising: transport means for transporting an object; means for heat-treating the object to be transported; and a lifter according to claim 1. A heat treatment zone for heat-treating the object is provided in a plurality of stages in a direction substantially perpendicular to the transport direction of the object, and gas levitation means for floating the object in at least a part of the heat treatment zone is provided. The gas levitation means includes: (1) gas discharge means for blowing a gas to a part of the object, which exerts a levitation force for surfacing the object;
And (2) a gas supply means for supplying a gas to the gas discharge means, wherein the lifter is disposed adjacent to the heat treatment zone on at least one of the ends in the transport direction of the object in the heat treatment apparatus. Heat treatment equipment that is located. 8. The heat treatment apparatus according to claim 7, wherein the gas levitation means for levitating the object in the heat treatment zone is provided in a heating zone for heating the object in the heat treatment zone. 9. A heat treatment zone is provided in two stages, wherein at least a part of the upper heat treatment zone has a heating zone for heating the object, and at least a part of the lower heat treatment zone has the object. The heat treatment apparatus according to claim 7, wherein a cooling zone for cooling is provided. 10. The transfer means includes a contact member that abuts on a rear end of the target object and moves in a direction in which the target object is transported, and moves the target object by moving the contact member. The heat treatment apparatus according to any one of claims 7 to 9, wherein the heat treatment apparatus is configured to be pushed and transported. 11. The transporting means in at least one heat treatment zone has an abutting member that abuts on a rear end of the transporting member carrying the object and moves along the transporting direction of the object. The heat treatment apparatus according to any one of claims 7 to 9, wherein the movement of the contact member pushes and transports the transport member and an object carried thereon. 12. A heat treatment zone for heat-treating an object to be conveyed is provided in a plurality of stages in a direction substantially perpendicular to a direction in which the object is conveyed. In a heat treatment apparatus performed using the heat treatment method, when moving an object between a heat treatment zone and a lifter, at least one of the movements is performed in a state where the object is floated. 13. The heat treatment method according to claim 12, wherein when the high-temperature object is moved from the heat treatment zone to the lifter, the movement is performed while the object is levitated. 14. The heat treatment method according to claim 12, wherein when moving the arm, the object is not lifted from the mounting means. 15. When the target object is moved between the heat treatment zone and the lifter, by moving the contact member that abuts on the rear end of the target object and moves along the transport direction of the target object. The heat treatment method according to any one of claims 12 to 14, wherein the object is pressed to move the object. 16. When moving an object between the heat treatment zone and the lifter, the object moves in the conveying direction of the object while being in contact with the rear end of the conveying member carrying the object. The heat treatment method according to any one of claims 12 to 14, wherein the transport member is pushed by moving the contact member, thereby moving the transport member and the object held thereon.