JPS63278634A - Foundry sand supply and recovery system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a system for supplying and recovering molding sand that forms a mold during casting. The present invention relates to a molding sand supply and recovery system that is capable of quickly recovering the foundry sand by utilizing the labor savings and supplying the recovered foundry sand into the frame when reusing it.

(Conventional technology) The molding sand in the closed casting frame that has been separated from the mold after vacuum casting is
It is reused in the same condition as it was collected. In particular, the foundry sand used in the so-called full mold casting process, which uses a vanishing model mainly made of synthetic resin as a model, is a binder similar to general foundry sand that uses wooden molds, metal molds, etc. as the model. Because it does not contain any

Traditionally, such foundry sand recovery and supply systems
This is done by carrying the molded sand into a conveyor or other conveyor, which conveys it to a sand storage tank such as a hopper, where it is recovered, and when it is reused, it is dropped from the sand storage tank into a frame. There is.

(Problems to be Solved by the Invention) However, in the conventional collection and supply system, there are two steps: taking out the molded sand from the frame, and transporting the taken out molding sand to a conveying device such as a conveyor. It requires carrying in sand, and these operations require a lot of manpower and a relatively long working time, which has the problem of poor workability, and moreover, there is a risk of major damage to conveyors, etc. Since a large number of conveying devices are required, the amount of equipment increases, which is economically disadvantageous.

The present invention solves the problems of the conventional technology by focusing on the fact that the vacuum casting system has a suction function, and utilizes this suction function to quickly remove the molding sand that has been separated from the mold after casting by saving labor. It is an object of the present invention to provide a molding sand supply and recovery system that can improve workability by recovering the molding sand and that does not require a large-scale equipment and can therefore reduce the number of facilities.

(Means for Solving the Problems) In order to achieve the above object, the present invention connects the suction port of a vacuum pump to the exhaust port of a vacuum tank with a sand separator, which has a fine sand discharge port, an intake port, and an exhaust port. °The exhaust of the sealed sand storage tank with a sand separator, which is equipped with a vacuum casting system in which an intake pipe is connected to the intake port for sucking and discharging the gas in the sealed casting frame, and has a sand supply port, a sand suction port, and an exhaust port. The mold is connected to a vacuum tank with a sand separator in the vacuum casting system through an opening/closing means, and is deformed with an air flow from the sand suction opening to the sealed sand storage tank during operation of a vacuum pump with the opening/closing means opened. The molding sand in the closed casting frame is separated and recovered by suction, and the recovered molding sand is discharged and supplied into the closed casting frame from the sand supply port.

(Function) In the present invention, by opening the opening/closing means and operating the vacuum pump of the vacuum casting system, the molding sand in the molded sealed casting frame can be collected from the sand suction port into the sealed sand storage tank. When reusing, the sand can be supplied into the sealed casting frame from the sand supply port of the sealed sand storage tank.

(Example) FIG. 1 is a system diagram showing an example of the casting sand supply and recovery system according to the present invention. In the figure, 1 indicates a known vacuum casting system, and the suction port 2A of the vacuum pump 2 is A vacuum tank 3 with a sand separator having a fine sand discharge port 3A, an intake port 3B, and an exhaust port 3C is connected to the exhaust port 3C via a suction pipe 2B, and is inserted into the airtight casting frame 4 into the intake port 3B. An intake pipe 5 for suctioning and discharging the gas in the hermetic casting frame 4 is connected through a strainer 5A at the tip, and a valve 6 is interposed in the intake pipe 5.

Reference numeral 7 designates a sealed sand storage tank with a sand separator, the exhaust lower A of which is connected to the downstream side of the intake pipe 5 by an exhaust pipe 9 having a valve interposed therebetween as an opening/closing means 8. The sealed sand storage tank with a sand separator is made by vacuum casting in a sealed storage frame 4, and then sucking and introducing the dismantled mold, that is, foundry sand lO, from the sand sucking lower B through the sand sucking pipe 11 along with an air flow. , has the function of separating sand and air by centrifugal force, discharging the air from the exhaust lower A, and dropping the foundry sand 10 by its own weight and storing it inside, forming a sand supply lower C at the bottom thereof. ing.

The sand suction pipe 11 is made of, for example, a flexible tube, and has a valve 12 interposed at its tip.
0 is formed in a downward opening shape with a diameter that allows it to fall smoothly under its own weight, and a valve 13 is provided at the tip.

Inside the sealed sand storage tank 7 with a sand separator, a strainer 14 is provided above the sand absorption lower B, and
A cooling means 15 formed of a water jacket is provided on the outer periphery of the tank 3, and cooling water is introduced into the cooling means 15 from a cooling water supply source (not shown) through a water supply vibrator 15a, and is drained from a drain vibrator 15b. As a result, the foundry sand 10 is cooled through the peripheral wall of the closed sand storage tank 7.

Reference numeral 16 denotes a vanishing model made of polystyrene resin, for example, which is embedded in the mold as a prototype.

In the figure, 16a indicates a sprue.

Next, the operation of the above configuration will be explained. By performing casting from the sprue 16a, the vanishing model 16 embedded in the mold as a master model disappears, and a casting corresponding to the vanishing model 16 is formed in the mold IO. Then, by operating the vacuum pump 2 of the vacuum casting system 1 with the opening/closing means 8 closed and the valve 6 opened, the mold 1 in the hermetic casting flask 4 is
The gas contained in the mold 10 is introduced from the suction pipe 5 through the suction port 3B to the vacuum tank 3 with a sand separator, and is suctioned out from the exhaust port 3C of this tank 3 through the suction pipe 2B and suction port 2^, and the mold 10 is removed. The inside of the hermetic casting frame 4 is maintained in a predetermined vacuum atmosphere in order to increase its strength and to effectively eliminate the gas generated during pouring through the above-mentioned route to perform suitable casting.

In this case, the molding sand forming the mold IO is prevented from entering the intake pipe 5 by the strainer 5A, but even if fine sand should pass through the strainer 5A and enter the intake pipe 5. When this fine sand is sucked into the vacuum tank 3 with a sand separator, it is separated from the air by centrifugal force, and only this separated air is sucked into the vacuum pump 2 from the exhaust port 3C, causing damage to the vacuum pump 2. do not.

After waiting for the casting to cool down, the vacuum pump 2 is stopped, and then the upper lid of the hermetic casting frame 4 is opened, the mold IQ is disassembled, and the casting is taken out. Then, the valve 6 is closed, the opening/closing means 8 and the valve 12 are opened, and the vacuum pump 2 is opened.
is operated again and the sand suction pipe 11 is inserted into the closed casting frame 4. As a result, the molded molding sand 10 is sucked into the closed sand storage tank 7 from the sand suction lower B along with the air flow, and is swirled inside the tank 7, and the molding sand 10 and the air are separated by centrifugal force. Then, the air passes through the strainer 14 and is sucked into the vacuum tank 3 with a sand separator from the exhaust lower A through the exhaust pipe 9. From there, the air passes through the aforementioned ventilation path and is sucked into the suction port 2^ of the vacuum pump 2, where it is discharged. It is exhausted to the atmosphere from outlet 2C. Also foundry sand lO
All of the sand, including the fine particles caught by the strainer 14, fall to the bottom of the closed sand storage tank 7 and are collected and stored.

When all of the molding sand 10 in the molded sealed casting flask 4 is recovered, the valve 12 is closed and the vacuum pump 2 is stopped.

Since the outer periphery of the sealed sand storage tank 7 with a sand separator is cooled by the cooling means 15, the foundry sand lO recovered in the sand storage tank 7 is naturally rapidly cooled by the heat exchange action. Therefore, the temperature decreases to a temperature at which it can be reused in a short time, that is, a temperature at which the vanishing model 16 used as a prototype can maintain its original shape without losing its shape due to temperature rise. Therefore, the cycle time of the casting operation can be significantly shortened.

In order to reuse the recovered foundry sand lO that has been lowered to a predetermined temperature, it is sufficient to open the valve 13 of the sand supply lower C. By opening the valve 13, the foundry sand 10 is The sand is discharged and supplied from the sand lower C into the closed casting frame 4 which has been opened by gravity, and is reused as a mold.

Since the air exhausted from the exhaust lower part of the sealed sand storage tank 7 with a sand separator has sand components completely removed by the strainer 14, it will not damage the vacuum pump 2, as mentioned above. , instead of the strainer 14 provided inside the sealed sand storage tank 7, for example, a Y-shaped strainer 14 is installed in the exhaust pipe 9, as shown by the imaginary line.
It is also possible to adopt a configuration in which A is interposed. With this configuration, maintenance and inspection are easier than with the strainer 14, and clogging can be easily prevented.

FIG. 2 is a system diagram showing another embodiment of the present invention, in which the same or corresponding parts as in the previous embodiment are denoted by the same reference numerals, and the explanation thereof will be omitted. In this embodiment, the exhaust lower A of the sealed sand storage tank 7 with a sand separator is directly connected to the vacuum tank 3 with a sand separator via an exhaust pipe 9. Even if the structure is connected in this way, the same effects as in the above embodiment can be achieved.

Furthermore, as shown in FIG. 3, the cooling means 15 may be configured by arranging cooling water pipes in a spiral shape inside the sealed sand storage tank 7 with a sand separator, particularly in the part where the foundry sand 10 is stored. It has the same effect as the cooling means 15 described above.

(Effects of the Invention) According to the present invention, the exhaust port of a sealed sand storage tank with a sand separator, which has a sand supply port, a sand suction port, and an exhaust port, can be opened and closed via an opening/closing means in an existing vacuum casting system with a sand separator. When a vacuum pump connected to the tank and opening the opening/closing means is operated, the molding sand in the sealed casting frame that has been deformed with air flow from the sand suction port to the sealed sand storage tank is sucked and separated and recovered, and the sand is collected. Since the molding sand is discharged and supplied into the closed casting frame from the sand supply port of the closed sand storage tank, it does not require many workers unlike the conventional molding sand recovery and supply system. It can be quickly collected by human workers, significantly improving work efficiency. In addition, since it utilizes the existing vacuum casting system and does not require a dedicated molding sand conveying device such as a conveyor, which can be costly,
The equipment cost can be reduced and it is economically advantageous.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing one embodiment of the present invention, FIG. 2 is a system diagram showing an embodiment of the same, and FIG. 3 is an explanatory diagram showing another embodiment of the cooling means. 1... Vacuum casting system 2... Vacuum pump 2A... Suction port 3... Vacuum tank with sand separator 3A... Fine sand discharge port 3B... Intake port 3C... Exhaust port 4. ... Sealed casting frame 5 ... Intake pipe. 7... Sealed sand storage tank with sand separator 7A-.
・Exhaust port A B... Sand suction port A C... Sand supply port 8... Opening/closing means 10... Foundry sand patent applicant Kubota Iron Works Co., Ltd. Agent
Patent Attorney Takashi Suzue - Figure 1 1″ Figure 2

Claims (1)

[Claims] (1) The suction port of the vacuum pump is connected to the exhaust port of a vacuum tank with a sand separator, which has a fine sand discharge port, an intake port, and an exhaust port, and an intake pipe for sucking and discharging the gas in the hermetic casting frame to the suction port. A sealed sand storage tank with a sand separator having a sand supply port, a sand suction port, and an exhaust port is connected to the vacuum tank with a sand separator in the vacuum casting system through an opening/closing means for the exhaust port. , when the vacuum pump with the opening/closing means opened is operated, the molding sand in the sealed casting flask that has been deformed with air flow from the sand suction port to the sealed sand storage tank is sucked and separated and recovered, and the recovered castings are collected. A casting sand supply and recovery system characterized in that sand is discharged and supplied from the sand supply port into the closed casting frame.