JPS6260446B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a vacuum metal heat treatment apparatus.

More specifically, the present invention relates to a metal heat treatment apparatus that performs quenching, solution treatment, and the like on a vacuum-heated workpiece by cooling it in an atmosphere isolated from the outside air.

[Prior Art] As is generally known, vacuum metal heat treatment equipment performs quenching, solution treatment, etc. on a vacuum-heated workpiece by cooling it in an atmosphere isolated from the outside air. However, this cooling means is roughly divided into oil-cooled type using an oil tank, salt-cooled type using salt bath, and gas-cooled type using inert gas such as N2 gas.

However, in the case of the oil-cooled type, processing at temperatures below 200°C is inevitable due to the risk of oil ignition, and therefore, only a limited number of steel types can be processed.

In addition, in the case of salt cooling type, since the salt must be kept in a molten state,
Processing at 600°C was inevitable, and even in this case, only a limited number of steel types could be processed.

Furthermore, the gas-cooled type has poor cooling ability, so it is forced to process at room temperature, and even with this, it is only possible to process materials of a limited number of steel types. .

In this way, conventional vacuum metal heat treatment equipment, regardless of its type, is forced to perform cooling treatment within a limited and narrow temperature range, and for this reason, unless at least two types of equipment are installed, it is necessary to install all kinds of steel types. It could not handle heat treatment.

[Problems to be Solved by the Invention] The present invention focuses on the above-mentioned problems, and as a result of intensive studies from various aspects in order to solve the problems, the present invention has developed a fluidized bed furnace as a cooling means for the vacuum-heated workpiece. They discovered that by using this method, cooling treatment can be performed over a wide temperature range, and a single device can be used to heat treat all types of steel.

[Means for Solving the Problems] That is, the vacuum metal heat treatment apparatus according to the present invention includes a vacuum furnace equipped with a heating chamber and a front chamber disposed on a cooling furnace, and a vacuum metal heat treatment apparatus according to the present invention. A vacuum metal heat treatment apparatus comprising: a first transfer device that transfers the workpiece between the chamber and the front space; and a second transfer device that transfers the workpiece between the front chamber and the cooling furnace; The furnace is composed of a fluidized bed furnace, and a movable door opens and closes a passage between the fluidized bed cooling furnace and the front chamber, and the powder and granules are separated from the gas discharged from the fluidized bed cooling furnace and the front chamber. The present invention is characterized in that it is equipped with a powder and granular material separator that performs the following operations, and a nozzle that injects compressed air to the processed material transferred from the fluidized bed cooling furnace to the front chamber.

[Example] Hereinafter, to describe more specifically based on the drawings, in FIG. 1 transfer device, 6 indicates a second transfer device, and the vacuum furnace 1 is equipped with a heating chamber 8 in the furnace shell 7, and, although not shown, a refrigerant supply capable of supplying refrigerant to the jacket portion 9 of the furnace shell 7. The heating chamber 8 is equipped with a vacuum pump device capable of evacuating the inside of the furnace shell 7, and the heating chamber 8 is provided with a peripheral wall 10 having a heat insulating structure. A plurality of electric heaters 11 are installed so that the Although not shown, a plurality of through holes are provided in the peripheral wall 10, and the inside of the heating chamber 8 and the inside of the furnace shell 7 are communicated through these holes.

On the other hand, the front chamber 2 connects the furnace shell 12 to the furnace shell 7 of the vacuum furnace 1.
The fluidized bed cooling furnace 3 is connected to the vacuum furnace 1 and is separated from the vacuum furnace 1 by a partition wall 13 having an adiabatic structure, and is arranged below the vacuum furnace 1 through a passage 14 provided in a structure that can shut off outside air. communicated via.

The fluidized bed cooling furnace 3 also includes a heat exchanger 15 of a type that circulates a refrigerant through pipes and an electric heater 1.
6 and is provided so that fluidizing gas can be supplied to the hearth from a pipe line 17. Note that the hearth is filled with heat-resistant powder (fluidized medium) such as alumina or zircon sand.

Further, the granular material separator 4 is provided so that the exhaust gas from the front chamber 2 and the fluidized bed cooling furnace 3 can be sucked in by the blower 18, and the granular material can be separated from the exhaust gas in the cyclone 19.

Further, the first transfer device 5 is composed of a cart device 20 provided in the front chamber 2 and a conveyor device 21 provided in the heating chamber 8, and the cart device 20 is a longitudinal cross-sectional view of the front chamber 2. As shown in FIG. 3, a plurality of rollers 24 are pivotally supported on the loading platform of a cart 23 that can be self-propelled guided by a pair of rails 22, and are connected to a motor 25 and a chain transmission mechanism (not shown). It is mounted so that it can be driven in forward and reverse rotations via etc.

The conveyor device 21 also moves a plurality of rollers 26 onto the peripheral wall 10 as shown in FIG.
and the furnace shell 7, and these are connected to the motor 27.
It is mounted so that it can be rotated in forward and reverse directions via a chain transmission mechanism (not shown) or the like.

In addition, 28, 29 shown in FIG.
is a movable door, and the movable door 28 is moved vertically by a fluid pressure actuator 30 to open and close the entrance/exit 31 of the heat radiation chamber 8; The passages 14 between the fluidized bed cooling furnace 3 and the front chamber 2 can be opened and closed by being moved in the horizontal direction by the cooling furnace 3 and the front chamber 2, respectively.

The second transfer device 6 will be described later, but during processing, the lid body 33 that constitutes the furnace shell 12 of the front chamber 2
is opened, the workpiece 34 is placed on the cart device 20 of the first transfer device 5 at the position A in the figure, that is, the workpiece 34 is placed at a predetermined position on the group of rollers 24, and then the lid is opened. 33 is tightened.

Then, the movable door 28 that closes the entrance/exit 31 of the heating chamber 8 is moved upward by the fluid pressure actuator 30, and the entrance/exit 31 of the heating chamber 8 is opened.

Next, the cart 23 of the cart device 20 moves toward the heating chamber 8 and is stopped at a point C in front of the entrance/exit 31. That is, the roller 24a (see FIG. 1) attached to the tip thereof is stopped at the entrance/exit 31.

Therefore, when the rollers 24 and 26 are subsequently driven to rotate by the motors 25 and 27, the object to be processed 34
is transferred from the trolley device 20 onto the conveyor device 21, and when the processed object 34 transferred onto the conveyor device 21 is carried to the heating position (position D in the figure), the drive of the motor 27 is stopped. be done.

Note that the drive of the motor 25 is stopped at the time when the object to be processed 34 is transferred onto the conveyor device 21, and when the drive of the motor 25 is stopped, the cart 23 moves by itself and is moved to the position shown in the figure B. Ru.

Subsequently, the movable door 28 is moved downward by the fluid pressure actuator 30 to close the entrance/exit 3 of the heating chamber 8.
1 is closed, the inside of the heating chamber 8 together with the inside of the furnace shell 7 is brought to a high vacuum by a vacuum pump device (not shown), and the temperature is raised by the electric heater 11. is heated to a predetermined temperature in a vacuum atmosphere.

Then, after a predetermined heating time has elapsed, the movable door 28 is moved upward again by the fluid pressure actuator 30, and then the carriage 28 of the carriage device 20
The robot moves by itself and is moved from the position shown in the figure B to the position shown in the figure C. That is, the roller 24a (see FIG. 1) is moved so as to be located at the entrance/exit 31.

Hereinafter, the rollers 24,
26 is rotationally driven and vacuum heated processing object 3
4 is transferred from the conveyor device 21 to the trolley device 20. At this time, the motor 27 is stopped when the workpiece 34 is transferred onto the trolley device 20, and the motor 25 is stopped. When the transferred workpiece 34 is brought to a predetermined position on the group of rollers 24, the drive is stopped.

Note that in this way, the front chamber 2 can be accessed from the inside of the heating chamber 8.
Prior to transferring the workpiece 34 into the front chamber 2, an inert gas, for example, N2 gas, is supplied to the front chamber 2 to purge the interior atmosphere.

This gas supply is performed by an inert gas supply device (not shown). Therefore, even if the object to be processed 34 heated to a high temperature is transferred into the front chamber 2, oxidation of the object can be prevented.

Further, when the driving of the motor 25 is stopped, the cart 23 of the cart device 20 moves by itself and is moved from the position C in the figure to the position B in the figure, and the movable door 28 is moved downward by the fluid pressure actuator 30. Then, the entrance/exit 31 is closed again.

Next, the workpiece 34 is transported to the position shown in B.
is transferred into the fluidized bed cooling furnace 3 by the second transfer device 6.

The second transfer device 6 includes a hydraulic actuator 35
A chuck 36 is attached to the tip of a piston rod, and the chuck 36 has a pair of claws 37 as shown enlarged in FIG.
is attached so that it can swing as shown by the arrow in the figure. Note that these claws 37 are provided with recesses 38 as shown in FIG.

Therefore, the chuck 36 positioned on the workpiece 34 can be moved downward by the fluid pressure actuator 35 and the hanging jig 39 can be gripped.

In this case, the pair of claws 37 are kept in the maximum swing state in the direction away from each other and are lowered, and when lowered to the grasping position, they are swinged in the direction closer to each other, as shown in FIG. Insert the narrow diameter part of the hanging jig 39 into the recess 38 so that it is firmly gripped. Note that the hanging jig 39 is
It is fixed to the upper end of the basket containing the objects 34 to be processed.

After this gripping, the basket is then moved slightly upward by the fluid pressure actuator 35, separated from the group of rollers 24 of the trolley device 20, and placed in a suspended state. Then, the cart 23 of the cart device 20 moves by itself and is moved from the position B to the position A in the figure.

Subsequently, the workpiece 34 is moved downward together with the basket by the fluid pressure actuator 35 and immersed into the fluidized bed.

At this time, the object to be processed 34 is moved downward passing between the pair of rails 22, but oxidation of the object to be processed 34 can be prevented even during this transfer, and the object to be processed 34 is not It is immersed in a fluidized bed of active gas atmosphere.

A passage 14 communicating between the fluidized bed cooling furnace 3 and the front chamber 2
is provided with a structure capable of blocking outside air, and the movable door 29 that closes this passage 14 is moved in the horizontal direction in advance before transferring the workpiece 34 to the fluidized bed cooling furnace 3. . Note that the movable door 29 is moved by a fluid pressure actuator 32.

In addition, in the fluidized bed cooling furnace 3, the pipe line 40,
Inert gas is supplied to the hearth through 17, and the powder and granules (fluidized medium) such as alumina are filled here.
is uniformly fluidized and heated by an electric heater 16 to form a heated fluidized bed in an inert atmosphere.

The heat exchanger 15 is used to prevent the temperature of the fluidized bed from rising above a predetermined cooling temperature when the vacuum-heated workpiece 34 is immersed in the fluidized bed. The gas that is used for
9, and the powder and granules (fluidized medium) in the gas are separated.

In this way, in the present invention, the fluidized bed cooling furnace 3
This furnace 3 has excellent thermal conductivity, and can control the furnace temperature over a wide range from room temperature to 800°C, for example, and can obtain a uniform temperature distribution. Steel grade workpiece 3
4 can be subjected to a predetermined cooling treatment.

Next, when the treatment in the furnace 3 is finished, the workpiece 34 is transferred into the front chamber 2 by the fluid pressure actuator 35. That is, the object to be processed 34 is transferred so that the lower end thereof is positioned slightly above the group of rollers 24 of the cart device 20.

Then, the cart 23 of the cart device 20 moves by itself from the position A to the position B in the figure, and then the pair of claws 37 of the chuck 36 holding the hanging jig 39 are separated from each other. The object to be processed 34 is moved onto the group of rollers 24 of the cart device 20 by being swung.

Subsequently, the powder (fluid medium) adhering to the object to be processed 34 is removed. This is done by injecting pressurized air from a group of nozzles 43 that are piped to the compressed air supply source. Then, when the pressurized air is injected for a certain period of time, the cart 23 of the cart device 20 moves by itself and is moved from the position B to the position A in the figure, and the workpiece 34 heat-treated in this way is The lid body 33 is opened to take it out of the room.

Note that when the workpiece 34 is transferred from the fluidized bed cooling furnace 3 into the front chamber 2, the fluid pressure actuator 32
As a result, the movable door 29 is moved to close the passage 14 as shown, and air is supplied to the hearth via the pipes 44 and 17. That is, the fluidized bed cooling furnace 3
In this case, an air atmosphere is prepared when the object to be processed 34 is not immersed, and an inert gas atmosphere is prepared when the object 34 is immersed.

Further, the gas in the front chamber 2 is sent to the cyclone 19 via the pipe 42, where the powder and granules in the gas are separated. Note that this gas feeding is interrupted by valve operation when an inert gas is supplied into the front chamber 2 for purging, and the vacuum-heated workpiece 34 is transferred from the front chamber 2 to the fluidized bed cooling furnace 3. Then, gas supply starts again.

In this way, in the present invention, in addition to the installation of the fluidized bed cooling furnace 3, the movable door 29, the powder separation device 4, and the nozzle 43 are installed, so that the heat-treated material can be transferred into the front chamber 2. It is possible to prevent the granular material (fluid medium) from being carried into the outside air along with the gas when taking the heat-treated object out of the chamber or introducing the heat-treated object into the front chamber 2 from the outside. At the same time, it can also be prevented from being carried into the outside air while adhering to the object to be treated, and therefore, outside air contamination can be prevented.

Although one embodiment has been described above, in the present invention, the heating means for the fluidized bed cooling furnace 3 and the heating chamber 8 may be provided with means other than electric heaters, and the first and second transfer devices may also be provided with other means. It may also be provided in the model.

[Effects of the Invention] As described above, according to the present invention, since the fluidized bed cooling furnace is provided, it is possible to heat treat various steel types to be treated in a prescribed manner with one device, and the present invention can be used in combination with the fluidized bed cooling furnace. A movable door that opens and closes the passage between the front chambers, a powder separation device that separates powder and granules from the gas discharged from the fluidized bed cooling furnace and the front chamber, and a granular material separation device that separates powder and granules from the gas discharged from the fluidized bed cooling furnace and the front chamber. The vacuum metal heat treatment equipment is equipped with a nozzle that injects compressed air onto the workpiece, so it can prevent the powder (fluid medium) from being carried into the outside air and prevent outside air contamination. Obtainable.

[Brief explanation of the drawing]

1 to 5 show embodiments of the present invention, FIG. 1 is a schematic configuration diagram of a vacuum metal heat treatment apparatus, FIG. 2 is a vertical cross-sectional view of the vacuum furnace 1, and FIG. 3 is a vertical cross-sectional view of the front chamber 2. 4 is an enlarged view of the chuck 36, and FIG. 5 is a perspective view of the claw 37 of the chuck 36. 1... Vacuum furnace, 2... Pre-chamber, 3... Fluidized bed cooling furnace, 4... Powder separation device, 5... First transfer device, 6... Second transfer device, 8... Heating chamber , 14...
...Aisle, 29...Movable door, 34...Object to be processed, 4
3...Nozzle that sprays compressed air.

Claims (1)

[Claims] 1. A first transfer device that connects a vacuum furnace equipped with a heating chamber and a front chamber disposed on a cooling furnace and transfers a workpiece between the heating chamber and the front chamber; In a vacuum metal heat treatment apparatus equipped with a second transfer device that transfers a workpiece between a front chamber and the cooling furnace, the cooling furnace is constituted by a fluidized bed furnace, and a a movable door that opens and closes a passageway; a powder and granular material separator that separates powder and granular materials from gas discharged from the fluidized bed cooling furnace and the front chamber; 1. A vacuum metal heat treatment apparatus, comprising: a nozzle for spraying compressed air onto a workpiece.