JP4753294B2 - Small vacuum carburizing furnace - Google Patents

Description

The present invention relates to a furnace body shape of a batch type small vacuum carburizing furnace having an entrance door, a cooling chamber, and a heating chamber, and having a relatively small amount of carburizing treatment in which the cooling chamber and the heating chamber are partitioned by an intermediate door.

Conventional batch-type vacuum carburizing furnaces having an entrance door, a cooling chamber, and a heating chamber and partitioning the cooling chamber and the heating chamber by an intermediate door are disclosed in Patent Documents 1 and 2, for example. Although it is not a vacuum carburizing furnace, Patent Document 3 proposes an inspection window for furnace maintenance in which a cupola is divided into two.
Japanese Patent Publication No.62-4464 Japanese Patent No. 2963869 JP 2002-31482 A

Unlike ordinary machines, heat treatment furnaces such as vacuum carburizing furnaces are operated at a high temperature, so that thermal deformation, material deterioration, embrittlement, etc. may occur. Therefore, regular maintenance is necessary to avoid sudden failures. For example, deterioration of a heat insulating material and vacuum carburizing over time will require replacement of the heat insulating material when soot and a polymer of hydrocarbon gas accumulate in the heat insulating material and the heat insulating effect deteriorates. The intermediate door is vacuum-sealed by a vacuum sealing O-ring, but the life of the vacuum sealing O-ring is shorter than that at normal room temperature and atmospheric pressure at high temperature under reduced pressure. Therefore, the O-ring for vacuum sealing of the intermediate door needs to be replaced periodically. Other machine parts are also exposed to relatively high temperatures, and may be deteriorated, deformed, or damaged. For example, when the amount of carburizing treatment is relatively small, for example, the processing amount of one batch is 100 to 200 kg, the furnace body is small and there is no space for sufficient maintenance work even if a person enters the furnace. If the furnace body is enlarged to improve maintainability, the amount of carburizing gas and nitrogen gas at the time of decompression will be larger than necessary, and a large vacuum pump for decompression will be required. Is big. In the vacuum carburizing furnaces described in Patent Documents 1 and 2, it is necessary to disassemble the apparatus mostly during maintenance including replacement of the heat insulating material in the heating chamber and replacement of the vacuum seal O-ring of the intermediate door and other mechanical parts. is there. Patent Document 3 proposes a large inspection window for furnace maintenance that divides the cupola into two parts, but is used for a cast iron melting cupola, and is operated under a vacuum pressure reduction as in the present invention. Not applicable to

An object of the present invention is to provide an apparatus for a batch type small vacuum carburizing furnace with a relatively small amount of carburizing treatment, for maintenance including replacement of a heat insulating material in a heating chamber, a vacuum seal O-ring for an intermediate door, and other mechanical parts. It is an object of the present invention to provide a small vacuum carburizing furnace that does not require a large disassembling work.

Therefore the present invention includes a cooling chamber having an inlet door has a heating chamber, the said cooling chamber and the heating chamber in a batch-type small vacuum carburizing furnace partitioned by an intermediate door, the heating chamber and the cooling chamber A first hinge that can be opened and closed, a plate that can be connected or disconnected from the outside to the outlet flange of the cooling chamber and the other to the inlet flange of the heating chamber, the plate and the heating chamber inlet flange, By uncoupling one of the cooling chamber outlet flanges, the heating chamber and the cooling chamber can be opened and closed via the first hinge, and the intermediate door that can be further moved up and down includes a second hinge. The above-mentioned problems have been solved by providing a small vacuum carburizing furnace attached to the plate via an opening / closing means .
Furthermore, in the invention of claim 2, the raising / lowering drive means of the intermediate door is adapted to be raised and lowered by meshing with the external gear inside the cooling chamber, and the outlet flange of the cooling chamber and the plate When the cooling chamber and the heating chamber are opened by the opening / closing means including the first hinge when the connection is released, the lifting / lowering driving means and the external gear are disengaged from each other. When the outlet flange and the previous plate are connected, the lifting drive means and the external gear are engaged with each other .

In the present invention, the first hinge that allows the cooling chamber and the heating chamber to be opened and closed, one of which can be connected or released from the outside to the outlet flange of the cooling chamber and the other to the inlet flange of the heating chamber, the plate and the heating chamber By opening the connection of either the inlet flange or the cooling chamber outlet flange, the heating chamber and the cooling chamber can be opened and closed via the first hinge, and the intermediate door that can be moved up and down further includes the second hinge. In the batch type small vacuum carburizing furnace, when furnace maintenance is required , check the equipment in the cooling chamber and the intermediate door, and replace the vacuum seal O-ring for the intermediate door. Can be performed in a state where the heating chamber is opened by 90 ° or more with respect to the cooling chamber by the opening / closing means including the first hinge, and the plate and the heating chamber inlet flange are disconnected. For example, when it is necessary to check and replace the heat insulating material, the bolts of the intermediate door flange corresponding to the second hinge attached to the plate are loosened, and the heating chamber is attached to the intermediate door attached to the plate by the second hinge means. It can be performed in an open state of 90 ° or more. This eliminates the need for large disassembly work during inspection and maintenance of the furnace body.

Preferably, the raising / lowering driving means of the intermediate door can be raised and lowered by meshing with an external gear inside the cooling chamber, the outlet flange of the cooling chamber and the plate are disconnected, and the first hinge When the cooling chamber and the heating chamber are opened by the opening / closing means including the mesh, the lifting drive means and the external gear are disengaged, and the outlet flange of the cooling chamber and the previous plate are connected. When the heating chamber is opened together with the plate, the lifting / lowering driving means and the external gear mesh with each other, so that the external gear is disengaged when the heating chamber is opened.

An example of the best mode for carrying out the present invention will be described with reference to FIGS. 1 is a schematic side sectional view of a small vacuum carburizing furnace according to an embodiment of the present invention, FIG. 2 is a schematic plan sectional view taken along line AA in FIG. 1, and FIG. 3 is a cooling chamber, plate and intermediate door in FIG. FIG. 4 is a detailed enlarged view of the connecting portion of the heating chamber. FIG. 4 is a view showing that the connection between the cooling chamber outlet flange 33 and the plate 60 is released while the plate 60 of FIG. schematic diagram showing an open state of 90 ° or more with intermediate door heating chamber to the cooling chamber with respect to the cooling chamber by opening and closing means including, from the state of FIG. 5 FIG. 4, corresponding to the second hinge attached to the plate FIG . 6 is a schematic view showing a state in which the bolt of the intermediate door flange is loosened and the intermediate door 4 of the plate attached to the heating chamber is opened 90 ° or more by the second hinge means, and FIG. 6 is attached to the outlet flange of the cooling chamber. Leave the heating chamber inlet flange and play The schematic diagram which shows when the heating chamber is opened with respect to the cooling chamber by the opening / closing means including the first hinge, and the heat insulating material supported by the heat insulating frame is taken out from the heating chamber is shown.

A small vacuum carburizing furnace according to an embodiment of the present invention has an inlet door 1, a cooling chamber 2, and a heating chamber 3 from the left in FIG. 1, and is relatively carburized by dividing the cooling chamber 2 and the heating chamber 3 by an intermediate door 4. It is a batch type small vacuum carburizing furnace with a small amount of processing. In the present invention, a plate 60 is provided between the cooling chamber outlet flange 33 and the heating chamber 3, the plate 60 is connected to the cooling chamber outlet flange 33 with a bolt 28 (FIG. 3), and the plate 60 is connected to the heating chamber inlet flange 6. The cooling chamber 2 and the heating chamber 3 are connected to each other, and the cooling chamber 2 and the heating chamber 3 are connected via an opening / closing means including the arms 20 and 21 and the first hinge 5. The bolts 28 (FIG. 3) are loosened so that the connection between the plate 60 and the heating chamber inlet flange 6 can be opened and closed (the state of FIG. 4). Further, the intermediate door 4 that can be moved up and down is attached to the plate 60 via an opening / closing means including the second hinge 40 so that the intermediate door 4 can be opened and closed with respect to the heating chamber 3, the heating chamber 3 is formed into a vertical cylindrical shape, and cooled. while opening the heating chamber 3 by opening and closing means comprising a first hinge 5 against the chamber 2, and was opened to the heating chamber 3 by opening and closing means including a second hinge 40 with respect to the intermediate door 4 (Figure 5 state). In the cooling chamber 2, an in-furnace transfer device 30 (FIG. 2) for the workpiece 8 and a lifting device (not shown) for immersing the workpiece 8 in the oil 9 are provided. The intermediate door 4 that can be moved up and down between the cooling chamber 2 and the heating chamber 3 is attached to a plate 60 connected to the cooling chamber outlet flange 33 via a sealing plate 29, and the endless chain 17 that lifts and lowers the heating chamber 3 is driven up and down. It can be opened and closed. In the heating chamber 3, a heater 22 and a heat insulating material 11 supported by a heat insulating frame (not shown) surrounding the heater 22 are arranged.

As can be seen from the detailed enlarged view of FIG. 2 shown in FIG. 3, the intermediate door 4 is connected to the endless chain 17 via external gears 14 and 15 extending from the elevating drive means 13 provided outside the cooling chamber to the inside of the cooling chamber. The intermediate door 4 is moved up and down by meshing the external gears 14 and 15 taken into the cooling chamber 2, and the plate 60 remains connected to the heating chamber 3 by the opening / closing means including the first hinge 5. When the heating chamber 3 is opened, the external gears 14 and 15 are disengaged, so that when the heating chamber is opened, only the disengagement of the external gear is disengaged and no further disassembly work is required. At the descending end, the link devices 18 and 19 are pressed against the heating chamber via the sealing plate 29. One endless chain 17 is provided on each side of the center of the workpiece 8 in the flow direction, and the support shaft 26 of the chain wheel 16 of the endless chain 17 is attached to the plate 60 by an angle member 27. The plate 60 affixed to the cooling chamber outlet flange 33 has a water cooling jacket 25, and the sealing plate 29 is placed in the vacuum sealing O-ring 23 placed in the vacuum sealing O-ring groove and the water cooling jacket sealing groove. The water cooling jacket seal 24 is provided, and the vacuum seal O-ring 23 is cooled by the water cooling jacket 25.

In operation, the vacuum seal O-ring 23 is repeatedly crushed and returned to its original state every time the intermediate door 4 is opened and closed. Since the plate 60 is cooled by the water cooling jacket 25, the deterioration of the vacuum seal O-ring 23 provided on the sealing plate 29 due to heat can be avoided, but the elasticity of the vacuum seal O-ring 23 deteriorates with time. . Therefore, the vacuum seal O-ring 23 needs to be replaced periodically. However, in the vacuum carburizing furnaces described in Patent Documents 1 and 2, the heating chamber is integrated with the cooling chamber, the furnace body is small, and the inlet is small. It was difficult for humans to enter the furnace, and it was necessary to disassemble the heating chamber and separate it from the cooling chamber when replacing it.

In the present invention, a plate 60 is provided between the cooling chamber outlet flange 33 and the heating chamber 3, the plate 60 is connected to the cooling chamber outlet flange 6, and the plate 60 and the heating chamber inlet flange 6 are connected to the bolt 32 (FIG. 3). The cooling chamber 2 and the heating chamber 3 are connected to each other, and the cooling chamber 2 and the heating chamber 3 are connected to each other via an opening / closing means including the arms 20 and 21 and the first hinge 5 so that the plate can be opened and closed. 60 and the heating chamber inlet flange 6 can be opened and closed with each other by loosening the bolt 32 (FIG. 3) to release the connection, and the intermediate door 4 that can be raised and lowered is attached to the plate 60 connected to the cooling chamber outlet flange 33, than the heating chamber 3 has a vertical cylindrical shape, a batch-type when in compact vacuum carburizing furnace requires maintenance of the furnace occurs, inspection and vacuum seal of the intermediate door 4 of the apparatus and the intermediate door 4 portions in the cooling chamber 2 O-ring 3 for replacement solves coupling the plate 60 and the cooling chamber outlet flange 33 by loosening the bolts 28, with respect to the cooling chamber 2 by opening and closing means comprising a first hinge 5 and arm 20, 21, the intermediate door 4 and heating the chamber 3 Ru can be performed in a state of open more than 90 ° (Figure 4). For example, when inspection and replacement of the heat insulating material 11 in the heating chamber 3 is necessary, the bolt 32 is loosened to disconnect the plate 60 from the heating chamber inlet flange 6 and heat the cooling chamber 2 and the intermediate door 4. The chamber 3 was opened and the heat insulating material was removed (state of FIG. 6) . This eliminates the need for large disassembly work during inspection and maintenance of the furnace body.

Since the raising / lowering drive of the intermediate door 4 is performed by the external gears 14 and 15 taken into the cooling chamber from the driving means 13 outside the cooling chamber, the bolts 28 (FIG. 3) are loosened between the plate 60 and the cooling chamber outlet flange 33. When disconnecting and opening the heating chamber 3, the external gears 14 and 15 are disengaged, so there is no need to disassemble the heating chamber 3 and the intermediate door 4. Restoration from the state of FIGS. 4 and 5 to the original position is not a problem as long as the arms 20 and 21 and the first hinge 5 means are sufficiently strong. Since the chain 15, the sprocket 16, the bearings, and the parts for driving the intermediate door 4 are exposed to relatively high temperatures, deterioration, deformation, and damage are considered, and periodic inspection and periodic replacement are necessary. In the vacuum carburizing furnaces described in Patent Documents 1 and 2, as with the above-described replacement of the vacuum seal O-ring 23, it is difficult to enter the furnace, so the heating chamber must be separated from the cooling chamber. However, in the present invention, as described above, it is possible to check and repair the inside of the cooling chamber and the heating chamber from the outside.

1 is a schematic side sectional view of a small vacuum carburizing furnace according to an embodiment of the present invention. FIG. 2 is a schematic plan sectional view taken along line AA in FIG. 1. FIG. 3 is a detailed partial enlarged view of a connecting portion of a cooling chamber, a plate, an intermediate door, and a heating chamber in FIG. 2. The schematic which shows the state which opened | released the intermediate | middle door and the heating chamber 90 degrees or more with respect to the cooling chamber with the opening / closing means containing a hinge by releasing the connection of the plate and cooling chamber exit flange of FIG. FIG. 5 is a schematic view showing a state in which the intermediate door corresponding to the second hinge attached to the plate and the bolt of the flange are loosened from the state of FIG. 4 and the intermediate door is opened 90 ° or more by the second hinge means. Schematic which shows when the heat insulating material supported with the heat insulation frame was taken out from the heating chamber.

1: Entrance door 2: Cooling chamber 3: Heating chamber 4: Intermediate door 5: First hinge (opening / closing means)
6: Heating chamber inlet flange 33: Cooling chamber outlet flange 40: Second hinge (opening / closing means)
60: Plate
14, 15: circumscribed gear

Claims (2)

Has a cooling chamber having an inlet door, a heating chamber, a,
In a batch-type small vacuum carburizing furnace partitioned said heating chamber and said cooling chamber at an intermediate door,
A first hinge capable of opening and closing the cooling chamber and the heating chamber;
A plate that can be connected or released from the outside to the outlet flange of the cooling chamber and the other to the inlet flange of the heating chamber;
By uncoupling either the plate and the heating chamber inlet flange or the cooling chamber outlet flange,
The heating chamber and the cooling chamber can be opened and closed via the first hinge,
Further, the intermediate door that can be moved up and down is attached to the plate via opening / closing means including a second hinge . The raising / lowering drive means of the intermediate door is adapted to be raised and lowered by meshing with the external gear inside the cooling chamber,
When the connection between the outlet flange of the cooling chamber and the plate is released and the cooling chamber and the heating chamber are opened by the opening / closing means including the first hinge, the elevating driving means and the external gear are not engaged. To be
2. The small vacuum carburizing furnace according to claim 1, wherein when the outlet flange of the cooling chamber and the previous plate are connected, the elevating drive means and the external gear are engaged with each other .

Images