JPH073340A - Continuous processing device - Google Patents

Abstract

(57) [Summary] [Purpose] In a continuous processing system having two or more processing chambers with different atmospheres, the size and weight can be reduced and the structure is simple. To be able to do. [Structure] A swing arm 1 is installed at an end of a transfer device 6 of an object to be processed 7 installed in a processing chamber 14 opposed to a transfer device 5, and can be vertically moved to separate the processing chambers 13 and 14 from each other. The intermediate door 4 is arranged, and the swing arm 1 and the intermediate door 4 are arranged.
The lower end of the swing arm 1 is connected by the connecting chain 3 so that the swing arm 1 is interlocked with the vertical movement of the intermediate door 4, and the first position on the transfer path of the workpiece 7 and the second position retracted therefrom. Allow rocking to and from the position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous processing apparatus having two or more processing chambers having different atmospheres, and more particularly to an apparatus for continuously moving an object to be processed between the processing chambers.

[0002]

2. Description of the Related Art Generally, a continuous processing apparatus is an apparatus having different purposes in different atmospheres in different chambers. For example, a vacuum heat treatment furnace, a vacuum carburizing furnace, an ion carburizing furnace, and an ion nitriding furnace are used for vacuum heating. It can be used in a wide range of fields such as an apparatus or an ion engineering surface reforming apparatus such as ion plating, ion sputtering, ion implantation, and ion milling, a gas carburizing furnace, a gas nitriding furnace, an annealing furnace, and a soldering furnace.

An ordinary pressure continuous gas carburizing furnace will be briefly described as an example of a conventional object transporting apparatus having two or more processing chambers. This continuous gas carburizing furnace has a tray pressure method and a roller hearth method.The former is a method in which trays stacked in several stages are sequentially pushed out by a cylinder or the like and conveyed along a guide rail, and the latter is an external This is a system in which the rollers arranged inside the equipment are rotated by a drive system and the tray moves over them. These continuous gas carburizing furnaces are categorized into a preheating zone, a carburizing zone, and a diffusion zone by the gas inlet, agitation fan, exhaust port, and frame curtains at the inlet and outlet, etc. Yes, the process is performed by roughly dividing the gas flow. However, in these methods, since guide rails and rollers are installed between each room and the opening / closing door cannot be installed at that position,
It becomes impossible to seal each room, and it is impossible to transfer between the rooms having strictly different atmospheres.

In contrast to this, as an apparatus targeted by the present invention, that is, an apparatus for carrying out a desired treatment in two or more processing chambers having different atmospheres and then opening the door between the chambers to convey the object to be treated. In the related art, a means for supporting a tray on which an object is placed from the front chamber by, for example, two forks and transporting the tray to the next chamber has been widely used. This is the method currently practiced by most manufacturers of vacuum heat treatment equipment in Japan and overseas, and most of the doors between the chambers are gate valves that can shut off the vacuum, and the forks are electrically driven for each treatment chamber. A mechanism for moving the object and a device for raising and lowering the object to be processed are provided.

Further, in the apparatus disclosed in Japanese Patent Laid-Open No. 61-207569, a combination of a mechanism for moving a fork with a cylinder and an elevating device is adopted, which is described in Japanese Patent Laid-Open No. 61-257462. The apparatus employs a drawer that draws out a tray on which an object to be processed is mounted by using a strong magnet.

[0006]

Of the above-mentioned conventional techniques,
A device for supporting a tray on which an object to be processed is placed by two forks and transporting it to the next chamber requires a gate valve, a fork moving mechanism, an object elevating device, and the like, so the internal structure of the furnace is complicated. In addition, since the inner diameter of the furnace becomes large, a large amount of furnace body materials, heat insulating materials, reflectors, etc. are required, which increases equipment costs. Further, the complicated structure and control are likely to cause troubles in work, and the more the number of rooms, the more serious the adverse effect.

The devices described in JP-A-61-207569 and JP-A-61-257462 also have the drawbacks that the internal structure of the equipment is complicated and that the transport speed is slow, so that the material to be processed can be processed smoothly. It cannot be said that it is an apparatus having an article conveying means.

It is an object of the present invention to provide a continuous processing apparatus having a simple structure which can be made compact and lightweight, and which can easily and quickly carry an object to be processed between processing chambers.

[0009]

In order to solve the above-mentioned object, the present invention is arranged between at least two processing chambers having different atmospheres and the processing chambers, and is vertically movable to separate the processing chambers from each other. In a continuous processing apparatus having an intermediate door and a transfer device for the processing object arranged in each of the processing chambers, at least one of opposing ends of the transfer devices is on the transfer path for the processing object. An auxiliary transfer device provided so as to be able to move back and forth between a first position and a second position that does not interfere with the operation of the intermediate door retracted therefrom, and the auxiliary transfer device is interlocked with the operation of the intermediate door. Then, the first and second
Drive means for moving back and forth between positions.

Preferably, the auxiliary transfer device has a swing arm swingable between the first position and the second position, and the drive means connects the intermediate door and the swing arm. Has a connecting chain.

[0011]

According to the present invention, at least one of the opposing ends of the transfer devices is provided so as to be movable back and forth between the first position on the transfer path of the object to be processed and the second position retracted therefrom. Since the auxiliary transfer device provided and the drive means for moving the auxiliary transfer device back and forth in conjunction with the operation of the intermediate door are provided,
As the intermediate door is raised to convey the material to be processed, one or both of the auxiliary conveying devices located between the chambers are interlocked with this to raise the same height on the conveying path of the object to be treated. By advancing up to that point, it becomes possible to supplement the space between the transfer devices in each chamber and smoothly transfer the object to be processed between the chambers. Further, since the auxiliary transfer device operates in conjunction with the intermediate door, it can be transferred in a short time.

When the movement of the object to be processed is completed, the intermediate door is lowered in order to isolate the chambers from each other. In conjunction with this, the auxiliary transfer device moves the intermediate door from the transfer path of the object to be processed. Since it moves to a retracted position that does not interfere with the above, the intermediate door can again isolate the processing chambers.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A continuous processing apparatus according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a sectional view of the continuous processing apparatus according to the present embodiment, which is an overall continuous processing apparatus for ion nitriding using DC plasma.
Further, FIG. 2 is a detailed view of a swing arm type transfer mechanism which is a main part of the continuous processing apparatus according to the present embodiment.

First, the structure of the continuous processing apparatus according to this embodiment will be described with reference to FIG. The entire processing chamber of this device is a furnace body 10.
This furnace body 10 comprises an ion nitriding chamber 13 and a cooling chamber 1.
It consists of 4 consecutive 2 rooms. The ion nitriding chamber 13 has a carrier device 5, an ion processing electrode 8, and a lifting cylinder 9.
Is installed, and the transport device 6 and the cooling fan 1 are installed in the cooling chamber.
1 and the heat exchanger 12 are installed. Further, between the two chambers, an intermediate door 4 for separating the two chambers, a hydraulic cylinder 4a for vertically moving the intermediate door 4, and a piston rod 4b are provided.
Is installed. Further, a vacuum pump 15 is installed below both processing chambers, and the valves 16 and 17 are opened to evacuate both chambers to evacuate both chambers. A vacuum equalizing valve 18 for equalizing the pressures in both chambers is provided at the position shown in the figure.

The swing arm type transfer mechanism, which is the main part of the present invention, is installed between both processing chambers, but the ion nitriding chamber, which is the main processing chamber for generating plasma, is the first chamber and its cleanness is high. In consideration of the simplification of the indoor structure, the stability of discharge, and the ease with which by-products (carbon, carbide, oxides, etc.) can be removed, the swing arm 1 is provided on the transfer device 6 on the second chamber side. is there.

Next, details of the swing arm type transfer mechanism will be described with reference to FIG. In FIG. 2, the swing arm 1, which is an auxiliary transfer device, is on the transfer path of the object 7 (see FIG. 1) as indicated by the solid line in the figure, that is, at the same height as the transfer devices 5 and 6. The central shaft 2a located at the end portion of the transport device 6 facing the transport device 5 between the position and the retracted second position that does not hinder the operation of the intermediate door 4 as shown by the chain double-dashed line in the figure. It is attached so that it can swing around. The intermediate door 4 can be moved up and down by a piston rod 4b attached to a hydraulic cylinder 4a (see FIG. 2) from a fully open position shown by a solid line to a closed position shown by a chain double-dashed line. The passage is sealed by and the processing chambers 13 and 14 are completely isolated. Further, the lower end of the intermediate door 4 is connected to the central shaft 2 on the side opposite to the central shaft 2a of the swing arm 1 by the connecting chain 3.
It is connected to b, which allows the swing arm 1
Will swing in conjunction with the vertical movement of the intermediate door 4.
Further, the transfer devices 5 and 6 are driven by an external drive electric motor, and the object 7 is transferred from the transfer device 5 on the processing chamber 13 side to the transfer device 6 on the processing chamber 14 side.

In the above swing arm type transfer mechanism, two processing chambers 13 and 14 are used to transfer the material to be processed.
When the intermediate door 4 for partitioning between the compartments and is lifted, the swing arm 1 is pulled by the connecting chain 3 connected to the lower end of the intermediate door 4 and the swing arm 1 rotates (swings) about the central shaft 2a. Then, when the intermediate door 4 rises to the uppermost position (fully open position), it swings to the position on the transfer path of the workpiece 7 as shown by the solid line in the figure, that is, to the position at the same height as the transfer devices 5 and 6. The arm 1 rises, and the space between the processing chambers 13 and 14 is supplemented so as not to hinder the transfer of the workpiece 7.
Therefore, the workpiece 7 is smoothly transported by the transport device 5 on the processing chamber 13 side and the transport device 6 on the processing chamber 14 side. When the movement of the object to be processed 7 is completed, the intermediate door 4 is lowered to separate the chambers from each other, and in conjunction with this, the swing arm 1 is moved along the path of the object 7 to be processed, that is, the transfer device 5. And the height of 6 moves to a position that does not hinder the operation of the intermediate door 4 as shown by the chain double-dashed line in the figure. Therefore, the intermediate door 4 descends to the original closed position, and the action of the seal ring 4c makes it possible to isolate the processing chambers from each other again.

Next, the ion nitriding process using the continuous processing apparatus according to this embodiment will be described with reference to FIG. First,
The object to be treated 7 is installed in the ion nitriding chamber 13 together with the transfer tray, and after closing the gate valve (not shown) on the inlet side, the valve 17 is opened and the ion nitriding chamber 13 is evacuated by the vacuum pump 15. After being degassed, the ion processing electrode 8 which also functions as an elevating device for the object to be processed 7 is lifted by the elevating cylinder 9 so that the object to be processed 7 is elevated and electrically connected to the cathode, followed by ion nitriding. At this time, since the present apparatus is a continuous apparatus, the cooling chamber 14 is in a vacuum state and N ₂ gas is being cooled. Next, when the nitriding in the ion nitriding chamber 13 is completed, the vacuum isobaric valve 18 with the cooling chamber 14 is opened so that the ion nitriding chamber 13 and the cooling chamber 14 become equal pressure, and the intermediate door 4 between both chambers is opened.
The (gate valve) rises to penetrate both chambers, and in conjunction with this, the swing arm 1 rises to the same height as the transfer device 6 by the connecting chain 3, and the transfer devices 5 and 6 operate. The workpiece 7 that has been nitrided in the ion nitriding chamber 13 is transferred to the cooling chamber 14. When the transfer of the object to be processed 7 is completed, the intermediate door 4 (gate valve) descends to separate the two chambers again, and as described above, the swing arm 1 descends to a position where it does not interfere with the operation of the intermediate door. . Next, valve 1
6 is opened, the cooling chamber 14 is evacuated by the vacuum pump 15, N ₂ gas is further introduced up to latm, and the object 7 to be processed is cooled by the cooling fan 11 and the heat exchanger 12. When the cooling in the cooling chamber 13 is completed, the cooling chamber 13
Is returned to atmospheric pressure by a leak valve (not shown), a gate valve (not shown) on the outlet side is opened, and the object 7 to be processed is carried out of the apparatus. After that, the gate valve on the outlet side is closed again, the valve 17 is opened, and the vacuum pump 15 is used to cool the cooling chamber 13.
Is evacuated under vacuum.

The results of actual ion nitriding using the above apparatus will be described below. Ion nitriding is performed in the ion nitriding chamber 13. Ion nitriding is a clean surface treatment method performed by utilizing the energy of direct current plasma, and since it can be performed at a relatively low temperature of 450 ° C. to 600 ° C., plastic working is performed. This is a method that has been put to practical use in many fields, including molds and automobile parts. Here, the processed object 7
As an armor shaft for automobile starter (diameter 18mm
The results of ion nitriding the (length 220 mm) are shown. The shaft material is JIS standard S molded by plastic working.
100 CM420s were installed vertically on the processing tray at equal intervals of 50 mm. First, 1x10 in the second room
Vacuum deaeration below ^-2 Torr, 30% N ₂ + 70% H ₂
After introducing the mixed gas of the above into the furnace and adjusting the gas pressure to 5 Torr, a DC voltage of 10 A and 400 V is applied between the furnace body which is the anode and the object 7 which is the cathode, and 550 ° C. × 5 h
An ion nitriding treatment of r was performed. After this nitriding treatment, the micro-hardness distribution of the shaft cross section was measured. As a result, a hardened layer with a surface hardness of Hv900 and an effective hardened layer depth of 0.3 mm was obtained. It was found that the variation was ± 4%. Further, in a microscopic observation with a metallurgical microscope, a white ε phase (Fe _2-3 N) having corrosion resistance is formed on the outermost surface in a thickness of 2 to 3 μm, and a γ ′ phase of a needle-like structure having excellent wear resistance is formed below the ε phase It was found that (Fe ₄ N) was formed in 0.45 mm and a good nitrided structure was formed.

Also, the same shaft is used with 3% CH ₄ + 33% H
850 ° C. × 40 mi using mixed gas of ₂ + 64% Ar
50% H ₂ +5 as diffusion treatment after ion carburizing treatment of n
When 850 ° C. × 60 min was performed using a mixed gas of 0% Ar, the surface carbon concentration was 0.68%, and it was found that carbon diffused to a depth of 0.6 mm from the surface of the EPM.
A (Electron Probe Micro An
alyzer).

According to this embodiment, the swing arm 1 is provided at the end of the carrier device 6 facing the carrier device 5, and the swing arm 1 is connected to the lower end of the intermediate door 4 via the connecting chain 3 to form the intermediate door. With a simple structure in which the swing arm 1 can be oscillated in conjunction with the vertical movement of the workpiece 4, quick and smooth transfer of the workpiece 7 between the processing chambers can be easily performed.

For example, as compared with the conventional transfer by a fork, the transfer time can be shortened to 1/3 to 1/5, and further, the inner diameter of the furnace can be reduced because of the simple structure, and the furnace such as the furnace material or the heat insulating material can be used. Since the internal components can be downsized, the facility cost can be reduced.

Since the device according to the present embodiment has a simple structure, it is considered that the trouble will not occur unless the connecting chain 3 is broken. For example, by checking the positions of the intermediate door 4 and the swing arm 1 by the light detecting device or the like. Anomalies can be detected.

Also, in this embodiment, the swing arm 1
Is provided only on the transport device 6 on the cooling chamber 14 side (next chamber side), but depending on the processing contents of the front and rear chambers, it should be provided only on the front chamber transport device, or on both the front chamber side and the rear chamber side. In some cases, it may be provided in. This is because, strictly speaking, the operation of the connecting chain and the swing arm causes the generation of abrasion powder. For example, when performing a sputtering process that requires a clean atmosphere in a certain processing chamber, the swing arm type transfer is performed. The mechanism should be installed either before or after the process chamber. In this way, when the continuous processing apparatus of the present invention is considered in a broad sense, the processing chamber in which the swing arm is to be installed is determined according to the purpose of a plurality of continuous processing chambers.

Further, in the present embodiment, an example of carrying in only one direction is shown, but it goes without saying that it is also applicable to carrying in reciprocation.

Further, although the example of the ion nitriding treatment or the ion carburizing treatment is shown in the present embodiment, it is not limited to this, and it is also used for the treatment such as general vacuum heat treatment, vacuum brazing, ion plating and ion implantation. be able to. In addition, it is also effective for gas carburizing treatment, for example, by providing 6 treatment chambers,
The first chamber is the spare chamber, the second chamber is the main carburizing chamber, the quenching oil layer is installed in the third chamber, and the degreasing layer is in the fourth chamber.
Further, by providing a heater for tempering in the fifth chamber and providing a cooling chamber in which a cooling fan is provided in the sixth chamber, the integrated carburizing process can be performed. As described above, the continuous processing apparatus according to the present invention can be used for a wide variety of processes.

[0027]

According to the present invention, an auxiliary conveying device is provided on at least one of the opposite ends of the conveying devices, and the auxiliary conveying device is connected to the lower end of the intermediate door through a connecting chain as a driving means. With a simple structure that allows the auxiliary transfer device to swing in conjunction with the vertical movement of the intermediate door, quick and smooth transfer of objects to be processed between processing chambers can be easily performed, and the size and weight of the device can be reduced. .

[Brief description of drawings]

FIG. 1 is a diagram of a continuous processing apparatus according to an embodiment of the present invention, and is a cross-sectional view of an entire continuous processing apparatus for an ion nitriding process using a DC plasma.

FIG. 2 is a detailed view of a swing arm type transfer mechanism which is a main part of the continuous processing apparatus shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Swing arm 3 Connection chain 4 Intermediate door 5,6 Transfer device 7 Processing object 13 Ion nitriding chamber 14 Cooling chamber

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masashi Ichikawa 3-4-6 Sumiyoshi-cho, Fuchu-shi, Tokyo Inside the Fuchu factory of JEOL Ltd. (72) Hideharu Yoshida 1-2-2 Nonaka Kita, Yodogawa-ku, Osaka No. 56 Inside the Osaka Factory of Nippon Electronics Industry Co., Ltd.

Claims (2)

[Claims] 1. At least two processing chambers having different atmospheres, a vertically movable intermediate door which is arranged between the processing chambers and separates the processing chambers from each other, and a processing object which is arranged in each of the processing chambers. In a continuous processing apparatus having an object conveying device, at least one of opposing ends of the conveying devices is provided with a first position on the object conveying path and an operation of the intermediate door retracted therefrom. An auxiliary transporting device that is provided so as to be able to move forward and backward between a second position that does not interfere with it, and the first and second auxiliary transporting devices that interlock with the operation of the intermediate door.
And a drive means for moving the position back and forth between the positions. 2. The auxiliary transporting device has a swing arm swingable between the first position and the second position,
The continuous processing apparatus according to claim 1, wherein the driving means has a connecting chain that connects the intermediate door and the swing arm.