JP3099437B2 - Centrifugal casting device in vacuum - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum melting / centrifugal casting apparatus for performing centrifugal casting following vacuum melting in a vacuum, and more specifically, a melting furnace, a centrifugal casting mold, and a mold in a vacuum tank. The present invention relates to a vacuum centrifugal casting apparatus including a drive mechanism assembly, and a moving device that enables the mold and the mold drive mechanism assembly to enter and exit a vacuum tank.

[0002]

2. Description of the Related Art In a conventional vacuum centrifugal casting apparatus having the structure shown in FIG. 4, the inside of a vacuum tank 1 is evacuated by a vacuum exhaust device (not shown), and vacuum melting is performed by an induction melting furnace 2. The centrifugal casting mold 3 is fixed to a rotating table 4 and drives a motor 9 by a rotating shaft 5, a bearing 6, a rotating shaft pulley 7, a motor shaft pulley 7a, and a rotation transmitting belt 8. Is rotated by The shaft seal 6a such as an O-ring transmits the rotation into the vacuum tank 1 while maintaining the degree of vacuum in the vacuum tank 1. With this configuration, the molten metal melted in the induction melting furnace 2 is poured through the tundish 3a into the centrifugal casting mold 3 that has been rotated by the above configuration.
After pouring, the air introduction valve (not shown) is opened, the inside of the vacuum tank 1 is set to the atmospheric pressure, the door 19 of the vacuum tank is opened, and the centrifugal casting mold 3 is taken out to obtain a casting as a product. I have.

[0003]

As shown in FIG. 4, in order to repeat the casting by taking out a cast product after melting and casting by a conventional vacuum melting and casting apparatus, the door 19 of the vacuum tank is opened and centrifugal casting is performed. The mold 3 is taken out and the cast product is taken out. After repairing as necessary, the centrifugally cast mold 3 taken out is returned to the vacuum tank 1, fixed on the rotating table 4, and then the door is opened. After closing, melting, and casting, it is necessary to repeat the operation of opening and removing the door each time as described above, and particularly when the centrifugal casting mold 3 is large, the operation becomes very troublesome. . Also in the vacuum tank 1
The rotary table 4 installed in the vacuum tank 1 must be removed even when performing another casting method such as gravity casting after vacuum melting, and the rotary table 4 is placed in the vacuum tank 1 for maintenance. And the work becomes very difficult. Therefore, a complicated centrifugal casting apparatus composed of members 3 to 9 in FIG. 4 is used as a mold and a mold driving mechanism assembly for rotating and driving the mold, and a structure in which these are integrally detachably connected to each other, and a vacuum There has been a demand for a vacuum melting and centrifugal casting apparatus that can freely enter and exit the tank. A motor that drives the mold to rotate
As a motor, a special motor such as a vacuum motor was required, and measures were required to use a normal motor that can be used under atmospheric pressure.

[0004]

To achieve the above object, the present invention provides a vacuum tank, a melting furnace housed in the vacuum tank, and a centrifugal casting housed in the vacuum tank. A mold, a rotary table on which the centrifugal casting mold is removably mounted, a drive motor for rotating the rotary table, a rotating shaft of the drive motor, and the rotary table;
A rotating shaft of the bull and a coupling mechanism between the two rotating shafts.
Bei a mold drive mechanism assembly, a moving device for and out of the centrifugal casting mold and out through the vacuum tank airtight door, a composed of
For example, at least the drive motor in the mold drive mechanism assembly is accommodated in a container which is hermetically sealed, the rotating
The engaging part between the rotating shaft of the table and the storage container is a shaft seal
, And the storage container is filled with a gas close to the atmospheric pressure. According to the second aspect, the gas sealed in the storage container is the atmosphere, and the inside of the storage container is communicated with the atmosphere outside the vacuum tank through a seal pipe including two circulation paths for flowing in and out of the atmosphere. Configuration. According to claim 3, the gas sealed in the storage container is an inert gas. According to claim 4, a fixing device for detachably fixing the mold and the mold driving mechanism assembly to the fixing member of the vacuum tank while being separated from the moving device, and a state in which the fixing member is released from fixing. The apparatus further includes an elevating device that moves up and down the certain mold and the mold driving mechanism assembly to load or release the load on the fixed member.

[0005]

In order to perform the melting and casting operations, the door of the vacuum chamber is opened, and the centrifugal casting mold on a moving device such as a moving trolley is guided into the vacuum chamber, and the casting mold, the rotating table and the motor storage container are integrated. While being mounted on the mobile trolley in a state where it is connected to the mobile trolley, or separated from the mobile trolley, it is fixed to the fixed base in the vacuum tank to complete the mounting. In this state, the weights of the centrifugal casting mold and the movable carriage are loaded on the fixed platform. Then, the door is closed, the inside of the vacuum tank is evacuated, the pressure is reduced to a predetermined degree of vacuum, and melting is started. When the melting is completed, the rotary table is rotated by the motor in the motor storage container to perform centrifugal casting. The motor container is
If the inside is filled with an inert gas such as argon, the inside of the vacuum tank and the atmosphere outside the tank are sealed and kept at atmospheric pressure, and the inside is filled with an inert gas such as argon. In addition, when it is communicated with the atmosphere outside the vacuum tank, it is kept at the atmospheric pressure, so that there is no need to use a special motor such as a vacuum motor, and the normal operation at the atmospheric pressure is not required. A motor can be used. After the casting is completed, the door is opened and the atmosphere is introduced into the tank, and the mold, the rotating table and the motor storage container housing the casting are integrally connected to the outside of the vacuum tank by the moving carriage. And the casting is taken out of the tank to complete a series of operations.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 and 2, the same members as those of the conventional device are denoted by the same reference numerals. FIG.
Is an overall arrangement of a centrifugal casting apparatus in a vacuum as an embodiment of the present invention.
In addition, arrangement of main members such as a mold driving mechanism assembly such as a rotary table 4, a rotating shaft 5, a bearing 6, a rotating shaft pulley 7, and a motor shaft pulley 7a, piping of cooling water into a motor housing 13, a motor 9 FIG. 2 is a front view showing connection with an external power supply. In order to avoid complicating the drawing, an apparatus for supporting and fixing a motor housing 13 described later is removed from FIG. FIG. 2 shows a device for supporting and fixing the motor housing 13 and the mold driving mechanism assembly, and is a side view schematically showing the device viewed from the direction of arrow AA in FIG. . In FIG. 1, reference numeral 1 denotes a vacuum tank, which is depressurized to a predetermined degree of vacuum by a vacuum exhaust device (not shown), and vacuum-melted by an induction melting furnace 2. The centrifugal casting mold 3 is fixed to a rotary table 4 and is rotated by a motor 9 driven by a rotary shaft 5, a bearing 6, a rotary shaft pulley 7, a motor shaft pulley 7a, and a rotation transmission belt 8. The connection mechanism between the two rotating shafts
Are the rotary shaft pulley 7, the motor shaft pulley 7a,
Lt 8 Reference numeral 13 denotes a storage container that stores the motor 9, the rotation shaft, the rotation shaft of the rotary table 4, the pulley, the belt, and the like, which are rotation transmitting means between the rotation shafts, and has an internal pressure equal to the atmospheric pressure. However, even if at least the motor 9 is housed, a normal motor such as a vacuum motor can be used without using a special motor. Storage container 1
An inert gas, for example, an argon gas may be sealed in the inside 3 so as to have an internal pressure equivalent to the atmospheric pressure. Alternatively, as shown in FIG. The container 13 may be communicated with two intake and exhaust seal pipes 19a and 19b that pass through the vacuum tank 1 to the atmosphere outside the vacuum tank 1 and may be detachable by a coupler 19c. The motor 9 is a normal motor that can be used in the atmosphere, and the shaft seal 6a seals between the vacuum tank 1 and the motor housing 13 having an internal pressure equal to the atmospheric pressure.

The cooling water inlet 11 and the cooling water outlet 11a attached to the motor housing 13 are provided with the cooling water after passing through the outlets A and C attached to the vacuum tank 1 at the cooling water outlet 11a.
Water is passed between the inner and outer walls of the motor storage container 13 to absorb heat generated during operation of the motor 9 and external heat. Cooling water outlet, inlet 11, 1
Couplers 11b and 11c are attached to 1a, respectively, so that the cooling water hose 11d connected to the cooling water inlet 11 and the cooling water outlet 11a can be easily attached and detached. . The motor power supply terminal 10
A motor is mounted on the inner wall of the vacuum tank 1 so as to seal between the vacuum in the vacuum tank 1 and the sealed gas 12 in the motor storage container 13 maintained at the same pressure as the atmospheric pressure. Power is supplied to the motor 9 from an external power supply by a power supply plug 10a and a power supply cable 10b through terminals similar to the current terminals B. When the sealed gas in the motor storage container 13 is the atmosphere, the motor storage container 13 passes through the vacuum chamber and is air-tightly communicated with the atmosphere outside the vacuum tank 1, and is normally supplied so that air flows in and out. Gas and exhaust pipes 19a and 19
b is attached.

Next, the operation of the vacuum induction melting apparatus of the present invention described with reference to FIGS. 1 and 2 will be described. The molten metal melted in the induction melting furnace 2 is poured into the centrifugal casting mold 3 rotated by the above configuration via the tundish 3a. After pouring, the inside of the vacuum tank 1 is returned to the atmosphere by an air introduction valve (not shown), and the door 19 of the vacuum tank 1 is opened.
Is opened, the centrifugal casting apparatus constituted by the members 3 to 13 is placed on the moving trolley 14, and the wheels 15 for moving the trolley are rotated to move the moving trolley 14 out of the vacuum tank 1 to produce the product from the centrifugal casting mold 3 Take out the casting. After removing the cast product, the centrifugal casting mold 3 is returned into the vacuum tank 1 by the moving carriage 14, and an apparatus for supporting the centrifugal casting mold 3;
The lifting device and the fixing device lift the centrifugal casting mold 3 from the moving carriage 14 to release the load on the moving wheels,
It is fixed to a fixed base in the vacuum tank 1 and the door 19 of the vacuum tank 1
Is closed, the inside of the vacuum tank 1 is returned to a vacuum, and melting and casting are restarted, and the above-described steps are repeated.

The centrifugal casting apparatus is placed on the movable carriage 14 and moved out of the vacuum tank 1, and the centrifugal casting apparatus after taking out the cast product is returned to the vacuum tank 1 and fixed by the elevating device and the fixing device, or The specific mechanism and operation for releasing the fixation and enabling the movement will be supplementarily described below with reference to FIG. First, a description will be given of a support device including a support arm 13a and an elevating screw rod 17 for supporting the centrifugal casting device constituted by the members 3 to 13 on the movable carriage 14 so as to be vertically movable. As shown in FIG. 3A, the screw holes 13 of the support arm 13a attached to the left, right, front, and rear of the outer wall of the motor storage container 13 are provided.
In FIG. 2B, an elevating screw rod 17 having a screw head formed as an elevating handle 17c is provided with a screw portion 1 cut into its shaft.
7a is screwed in, and the screw tip 17b is supported
A play that allows relative rotation with respect to the concave portion 14b at the upper end of the support pillar 14a which is vertically mounted on the movable carriage 14 and penetrates through the arm 13a and which can be moved only in an extremely short axial direction. Are connected with a gap. Therefore, the lifting handle 17 is rotated, and the screw tip 17 is rotated.
If the protrusion amount of b is made longer, the supporting arm 13a
The distance between the lower surface of the support column 14a and the upper end of the support column 14a is widened, and conversely, if the amount of protrusion is reduced, the distance is narrowed, and the entire centrifugal casting device supported by the support arm 13a is lifted from the movable carriage 14 to form a vacuum tank. It functions as a jack that moves up and down with respect to one fixed base 1a.

Next, a fixing device for fixing the centrifugal casting device supported by the support device in the vacuum tank 1 will be described. As shown in FIG. 3A, a fixing screw hole 1b drilled near an inner (left in the figure) end of a fixing base 1a mounted in the vacuum tank 1 has an outer end of the support arm 13a. Through the fixing hole 13c opened in the vicinity, the fixed handle 1
The handle screw portion 18a of No. 8 is attached and firmly tightened, so that the centrifugal casting device composed of the members 3 to 13 is lifted from the movable trolley while being supported, to the pouring position in the vacuum tank 1. It is fixed to suppress vibration etc. during operation of the centrifugal casting device. For this purpose, the supporting arm 13a
It is necessary to provide a fixing ring 13e at the upper end of the entrance of the fixing hole 13c, and to provide a gap in the recess 14b at the upper end of the support column 14a.

The operation of the fixing device will be described. When the melting and centrifugal casting in the vacuum tank 1 are completed and the entire centrifugal casting device is moved out of the vacuum tank 1, as shown in FIG. The fixing by the fixing handle 18 is released. At this time, a horseshoe-shaped clasp 18c is sandwiched between notches 18b provided on the shaft of the fixed handle 18 shown in FIG. 3A as shown in FIG. Hold in that position so that it does not fall. The fixed handle 18
May be detachable so that the centrifugal casting apparatus can be removed when moving. In this state, the restraint by the fixed stand is released, but the jack function of the support device is achieved by the weight of the movable carriage and the entire centrifugal casting apparatus. Therefore, FIG.
As shown in (C), when the screw tip portion 17b is extended by the lifting handle 17c and the lower end thereof is brought into contact with the bottom surface of the concave portion of the support column 14a, the lower surface of the support arm 13a is higher than the upper surface of the fixed base 1a. As a result, the weight of the movable carriage and the entire centrifugal casting apparatus is loaded on the movable wheels, and the movable carriage can be moved smoothly. Although not shown, the fixed handle and the lifting handle provided on each of the plurality of support arms may be linked with a sprocket and a chain, respectively. Further, the structure may be simplified, and the movable carriage 14 and the whole of the centrifugal casting apparatus 3 to 13 may be fixed to the fixed base 1a inside the vacuum tank 1 while being integrally connected.

In this state, the centrifugal casting apparatus and the movable carriage 14
Are a plurality of rows of wheels 1 serving as a truck moving mechanism via rails.
5 and the wheels 15 of the carriage moving mechanism
It can be easily moved if driven. When fixing the centrifugal casting apparatus in the vacuum tank 1, the movement and the fixing are performed in the reverse order to the above. The truck moving mechanism constituted by 15 and 16 in the figure performs vacuum melting using this vacuum tank, but when gravity casting is performed without centrifugal casting depending on the type of casting, a gravity casting mold is attached to the truck. Can be used to carry out gravity casting, and to move the mold inside and outside the vacuum tank for repair or the like.

[0013]

In the vacuum melting and vacuum centrifugal casting, 1) a motor for driving a mold mounting rotary table is housed in a closed storage container, and the inside of the container is filled with an inert gas or vacuum. It is communicated with the atmosphere outside the tank, and in any case, the inside is kept at the atmospheric pressure, and the motor does not need to use a special motor such as a vacuum motor. 2) The casting crystal can be easily taken out of the vacuum tank. However, even during casting, the entire centrifugal casting machine is separated from the mobile trolley or fixed up on the mobile trolley to fix the vacuum tank. Since it is configured to be fixed to the member, the problem of instability due to vibration or the like during casting does not occur. 3) It is a moving system using a trolley, and even in gravity casting,
Operations such as transporting, mounting, and removing the mold can be easily performed using a similar cart.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing an arrangement in a vacuum tank of one embodiment of a vacuum centrifugal casting apparatus of the present invention.

FIG. 2 is a side view showing a support, lifting and lowering and fixing device of the centrifugal casting device, as viewed from the direction of arrows AA in FIG. 1;

3 is a partially enlarged side view of a main part of the support, lifting and lowering and fixing device shown in FIG. 2, in which (A) shows a fixed state, (B) shows a released state, (C) shows a state in which the supporting arm of the centrifugal casting apparatus is slightly separated from the fixed base.

FIG. 4 is a schematic front view showing an arrangement in a vacuum tank of a conventional vacuum melting / centrifugal casting apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum tank 1a Fixing base 1b Fixing screw part 2 Induction melting furnace 3 Centrifugal casting mold 3a Tundish 4 Rotary table 5 Rotating shaft 6a Shaft seal 9 Motor 10a Power plug 11, 11a Cooling water inlet and outlet 12 Inside motor housing Filled gas 13 Motor storage container 13a Support arm 14 Moving trolley (moving device) 14a Support column 15 Bogie moving mechanism wheel 17 Elevating handle 18 Fixed handle 18a Fixed handle screw portion 19 Vacuum tank door 19a, 19b Seal for air supply and exhaust Piping

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B22D 13/10 B22D 13/06

Claims (4)

(57) [Claims] A vacuum tank; a melting furnace housed in the vacuum tank; a centrifugal casting mold housed in the vacuum tank; a rotary table on which the centrifugal casting mold is removably mounted; A drive motor and this drive to rotate the table
A rotating shaft of a dynamic motor, a rotating shaft of the rotary table,
A mold driving mechanism assembly comprising a coupling mechanism between the three rotating shafts; and a moving device for moving the centrifugal casting mold in and out through a vacuum tank airtight door , wherein at least one of the mold driving mechanism assemblies includes the drive motor is accommodated in a container which is hermetically sealed, the rotating tape
The engaging portion between the rotating shaft and the container of the Bull the shaft seal
A centrifugal casting apparatus in a vacuum, characterized in that the container is sealed with a rotary airtight seal and a gas close to the atmospheric pressure is sealed in the container. 2. The vacuum centrifugal casting apparatus according to claim 1, wherein the gas sealed in the storage container is the atmosphere,
A centrifugal casting apparatus in a vacuum, characterized in that the interior of the container is communicated with the atmosphere outside the vacuum tank through a seal pipe comprising two flow paths for flowing in and out of the atmosphere. 3. The vacuum centrifugal casting apparatus according to claim 1, wherein the gas sealed in the storage container is an inert gas. 4. The vacuum centrifugal casting apparatus according to claim 1, wherein the mold and the mold driving mechanism assembly are detachably fixed to a fixing member of the vacuum tank while being separated from the moving device. A lifting / lowering device for vertically moving the mold and the mold driving mechanism assembly in a state where the fixing member is released from the fixation, and applying or releasing the load to the fixation member. Casting equipment.