JPH1068061A - Device and method for subjecting metallic material to be treated to ion carburizing treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ion carburizing treatment method for machine elemental parts by which the production cost of equipment can be reduced, the process and the maintenance and repair of the equipment are facilitated, and the improvement of the productive efficiency of carburized products and the improvement of the quality in heat treatment thereof can be maximized and to provide a device therefor. SOLUTION: This device is provided with an ion carburizing treating chamber 32 for the material 31 to be treated connected with piping from a vacuum apparatus and a gas feeding source for carburizing, a cooling tank set to the part proximal to the chamber 32, a cap 38 put on the upper part of the carburizing treating chamber 32 and sealing it, and on the other hand, placing on the upper part of the cooling tank at the time of subjecting the material to be treated to direct quenching, a bed 39 for the material to be treated formed together with the cap 38 at the lower part of the cap 38 by a connecting rod 40 and an over head crane 36 capable of horizontally reciprocating the cap and bed between the carburizing treating chamber and cooling tank.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a metal workpiece (me).
The present invention relates to an ion carburizing method and apparatus of tal workpiece, and more specifically, a direct quenching technique in ion carburizing, which is a heating treatment technique for surface hardening of metal. (Quenching techno1og
y) improved apparatus and method.

[0002]

2. Description of the Related Art Ion carburization for surface hardening of metal workpieces is described in U.S. Pat. No. 5,383,980. Generally, in a high temperature plasma contact surface hardening heat treatment technology such as carburizing, a direct quenching process at an AC3 temperature or higher is an indispensable process for surface hardening. Accordingly, there has been a continuing need for a cooling method that is simpler and easier to adjust process variables.

[0003] An ion carburizing apparatus is disclosed in US Patent No. 4,462,577 issued to the United States of America, which includes a heating chamber and a cooling chamber (co.).
A vacuum furnace with an olling chamber is commonly used. The general configuration of an ion carburizing device is schematically illustrated in FIG.

The apparatus (10) shown in FIG. 1 has a heating chamber (11) and a cooling chamber (12), and has a two-chamber structure. The heating chamber (11) is connected to a manifold (14: manifold) from a gas supply system (13: gas supply system).

The auxiliary heater (15: auxili)
early heater and vacuum insert system (16: va)
cum system) is installed. On the other hand, the cooling chamber (12) has a vacuum system (16a), a gas cooling fan (17), and an oil heater (18: Oil h).
Eater) and oil circulator (19: oil)
(circulator) is installed.

[0006]

At present, a two-chamber type ion carburizing apparatus as shown in FIG. 1 has been widely used and applied to mass production lines worldwide. However, such existing equipment has a complicated configuration in which the configuration of the cooling chamber heat-treats the workpiece while maintaining a vacuum state. Due to such complexity, the price of the device is quite high. This means that the heating chamber must also maintain a vacuum, and the cooling oil must be usable in a vacuum.

[0007] Another problem is that many unnecessary devices are included in the equipment. Such unnecessary equipment raises the cost of the equipment. Also, there are many difficulties in maintaining and repairing equipment due to various factors such as mutual interference, noise, electromagnetic waves, and the like.

Therefore, it is difficult for ordinary workers who are not skilled professionals to work. In addition to the above two factors, there are also problems with equipment such as an increase in maintenance costs, limitations on the location of equipment, contamination of the carburizing chamber during cooling, and excessive use of public equipment.

Further, in the process, there are various problems such as a reduction in heat treatment quality due to a long transfer time when moving from the carburizing chamber to the heat treatment quenching chamber.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and an apparatus for ion-carburizing an object to be treated with a gold layer in which the production cost of the equipment can be reduced.

It is another object of the present invention to provide an ion carburizing method and apparatus which can easily operate and repair the apparatus.

Still another object of the present invention is to provide a method and an apparatus for ion carburizing a metal workpiece which can maximize the improvement of the production efficiency of carburized products and the quality of heat treatment.

[0013]

According to a first aspect of the present invention, there is provided an apparatus for ion carburizing an object to be treated in all layers, comprising: A vacuum chamber capable of carburizing the expanded workpiece, a cooling chamber for quenching the carburized Kinkei workpiece, and separating the metal workpiece from the vacuum chamber into a normal temperature state. An apparatus is provided, comprising a transfer means for moving the cooling chamber.

According to a second aspect of the present invention, there is provided a method for performing an ion carburizing process on a metal object, wherein a first step of generating a plasma in a vacuum chamber to carburize the metal object; There is provided a method comprising: a second step of separating the object to be processed from a vacuum chamber into a normal temperature state; and a third step of quenching the object to be cooled in a cooling bath.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a schematic view showing a configuration of an ion carburizing apparatus for a metal workpiece according to an embodiment of the present invention.

Referring to FIG. 2, the carburizing apparatus of the present invention is shown by reference numeral 30. The carburizing device (30) is provided with a carburizing chamber (32: carburiz) for carburizing a workpiece (31: work piece) which is a machine element part.
ing chamber) and a carburizing chamber (3
2) is connected to a pipe (not shown) for supplying a carburizing gas and an inert gas for increasing pressure.

A cooling chamber is provided in the vicinity of the carburizing chamber (32). A horizontal feed bar (34: forked feed bar) is installed at a position away from the upper surfaces of the two chambers while being supported by a support bar (35: support bar). An overhead crane (36) capable of reciprocating movement is provided on the lower surface of the horizontal feed piece (34). On the lower surface of the overhead crane (36), a shaft (37) that can move vertically up and down is installed. The end of the shaft (37) is put on the upper part of the carburizing chamber (32) when carburizing the workpiece (31), and is placed on the upper part of the cooling chamber (33) during cooling. 38) are connected together.
A loading platform (39: loading deck) for loading the workpiece (31) is integrally formed by a connecting rod (40: connection rod) below the lid (38). Therefore, the lid (38) and the carrier (39) reciprocate up and down integrally by the operation of the shaft (37).

First, when the object (31) is to be carburized, the object (31) is loaded on a carrier (39) and then carburized using an overhead crane (36). It is located at the top of the filling chamber (32). afterwards,
The cover (38) is connected to the carburizing chamber (3) by the shaft (37) to which the carrier (39) and the cover (38) are fixedly connected.
It is moved downward until it covers and seals the upper part of 2), and the carrier (39) on which the workpiece (31) is loaded is positioned inside the carburizing chamber (32).

Subsequently, the carburizing chamber (32) is maintained in a vacuum state, and the process (3) is carried out at an appropriate temperature and for an appropriate time by appropriate process modification according to the chemical components of the process (31).
After ion carburizing of 1), argon gas (argongas) is injected into the carburizing chamber (32) from a state where the high temperature is maintained, and the internal pressure is raised to 1 atm.

When the shaft (37) is moved upward, the carburized object (31) loaded on the lid (38) and the carrier (39) connected to the shaft (37) is moved from the chamber (32). Will be discharged.

Thereafter, an overhead crane (36)
Is moved about the horizontal feed piece (34), and the workpiece (3) is moved.
The loading platform (39) loaded with 1) is moved to the cooling chamber (33).
After being transported to the upper position, the shaft (37) of the overhead crane (36) is moved downward to move the loading platform (3).
9) is introduced into the cooling chamber (33) to load the cargo bed (3).
The object (31) loaded in 9) is directly quenched.

However, it is important at this time that the object to be treated (3
1) is how long it will be exposed to the atmosphere. This serves as an important factor in securing the heat treatment quality.

If the surface temperature of the object (31) is not reduced below the AC3 temperature, the overall heat treatment deformation amount can be reduced without affecting the quenching process quality of direct quenching. . This can be confirmed from FIG. 3, which is a graph showing a change in the temperature of the object to be processed with the transfer time. As shown in FIG. 3, the surface temperature does not drop below the AC3 temperature when the transfer time is less than about 2 minutes, preferably less than about 1.5 minutes.

Also, the formation of an oxide film on the surface shield which was worried by exposure to the atmosphere was not so worried as in the case of gas carburization.

The above-described process uses a simpler transfer device and a loader for the object to be treated as compared with the existing two-chamber ion carburizing furnace. Provide soil that can be used for surface hardening.

Such a series of steps can be adjusted by a simple S / V. When various processing changes such as processing temperature, processing time, cooling conditions, etc. are input and the start button is pressed, all the steps are performed. Since the workpiece can be automatically processed in sequence and the surface hardening heat treatment is completed, the ratio of labor cost included in the process cost can be reduced.
With a simple cooling system configuration, a system capable of easy maintenance and repair can be configured.

[0028]

As described above, the ion carburizing apparatus according to the present invention provides an improvement in the direct quenching system after carburizing, thereby reducing the manufacturing cost of equipment, making the process easier and easier to maintain. Various characteristics such as repair can be secured. In addition, high-quality ion carburizing equipment can be supplied at a relatively low price, and in particular, the production efficiency of carburized products and the quality of heat treatment can be maximized.

In particular, the apparatus according to the present invention can reduce processing costs by shortening the processing time when heat-treating mechanical parts for power transmission. Further, the possibility of lightweight design can be provided through maximization of wear resistance and fatigue resistance.

The present invention is not limited to the above-described embodiment, but can be variously modified without departing from the scope of the invention.

[0031]

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a general configuration of a conventional ion carburizing apparatus.

FIG. 2 is a schematic diagram showing a configuration of a carburizing apparatus according to one embodiment of the present invention.

FIG. 3 is a graph showing a change in temperature according to a transfer time of a metal workpiece in one embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 30 carburizing apparatus 31 workpiece 32 carburizing chamber 33 cooling chamber 34 horizontal feed piece 35 support piece 36 overhead crane 37 shaft 38 lid 39 carrier 40 connecting rod

Claims (6)

[Claims] 1. An apparatus for ion carburizing a metal workpiece, comprising: a carburizing chamber capable of carburizing the metal workpiece by generating plasma; and providing a carburizing chamber capable of carburizing the metal workpiece. An apparatus comprising: a cooling chamber for quenching; and a transfer unit for separating the metal workpiece from the carburizing chamber to a normal temperature state and moving the metal workpiece to the cooling chamber. 2. The carburizing chamber includes a carrier for loading the metal workpiece and a lid for opening and closing the carburizing chamber, wherein the carrier and the lid are integrally formed. The device according to claim 1. 3. The apparatus according to claim 2, wherein the loading platform and the lid are integrally transferred to the cooling chamber, and the lid opens and closes the cooling chamber. 4. The transfer means comprises a shaft for moving the metal workpiece up and down and a horizontal feeder provided with an overhead crane for horizontally transporting the metal workpiece. The device of claim 1, wherein 5. A method for ion carburizing a metal workpiece, wherein a first step of generating plasma in a vacuum chamber and carburizing the metal workpiece, and keeping the workpiece from the vacuum chamber at room temperature A second process of separating into
A method of quenching the workpiece in a cooling bath. 6. The method according to claim 1, wherein a moving time of the carburized workpiece from the vacuum chamber to the cooling chamber is about 2 minutes or less.