JPH0349782Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is a method for supplying a hardening agent to harden sand that has been mixed with a binder and molded into a predetermined shape to be used as a casting mold. This invention relates to a drug supply device.

[Conventional technology]

Casting molds, which are generally used to manufacture various cast products, are made by molding sand mixed with a binder such as water-soluble phenolic resin into a predetermined shape using a mold model in a molding container. In order to give the sand mixed with this binder a strength sufficient to withstand use as a casting mold, a hardening agent such as methyl formate is supplied into the molding container to harden the binder. It was manufactured.

Next, a conventional hardening agent supply device for manufacturing such a casting mold will be explained with reference to the drawings.

FIG. 4 is an explanatory diagram showing an example of a conventional curing agent supply device, in which the pressure of the liquid curing agent 2 stored in the curing agent storage tank 1 is adjusted through the supply air pressure regulating valve 3. The pressure of the compressed air supplied from the compressed air supply pipe 4 is supplied to the vaporizer 32 in a liquid state through the curing agent supply pipe 7 equipped with a curing agent supply valve 8 and a flow rate regulator 9, and the supply air pressure is increased. Air supply pipe 10 with regulating valve 11 and air supply valve 12
is supplied into the heating device 33 from the heating device 33.
After being mixed and vaporized in the vaporizer 32 with compressed air heated by a heat source 15 such as steam that is separately supplied into the vaporizer 32, the air is heated again through the heating container of the heating device 33. After that, the sand mixed with the binder is supplied into the molding container 22, which is formed into a predetermined shape, through the vaporized curing agent supply pipe 17.

[The problem that the idea aims to solve]

In such a conventional hardening agent supply device, the hardening agent 2 vaporized in the vaporizer 32 is supplied to the molding container 22 through the vaporized hardening agent supply pipe 17 . Due to heat radiation from the outside, the hardening agent 2 changes from a vaporized state to a condensed and liquefied state, and is no longer evenly distributed throughout the sand mixed with the binder in the molding container 22, resulting in its effectiveness as a hardening agent. The drawback was that it was not fully demonstrated.

The present invention solves the drawbacks of the conventional hardening agent supply device, and makes it possible to supply the hardening agent in a vaporized state without condensation and liquefaction into a molding container in which sand mixed with a binder is molded into a predetermined shape. An object of the present invention is to provide a curing agent supply device that can be used.

[Means to solve the problem]

As a result of various studies to solve this problem, the inventors of the present invention found that, like a conventional hardening agent supply device, the liquid hardening agent is mixed with heated air, the hardening agent is vaporized, and then the hardening agent is directly supplied to the molding container. Rather than mixing the liquid curing agent and compressed air, the mixture is passed through a heat transfer tube immersed in the heat transfer liquid in a vaporization heating device filled with the heat transfer liquid. The curing agent is completely vaporized by heating through fluidization, and then the outlet of the heat transfer tube is communicated with a molding container in which the sand mixed with the binding agent is molded into a predetermined shape. When supplying the vaporized hardening agent to the molding container through the vaporized hardening agent supply pipe, the heat transfer liquid is circulated from the vaporization heating device so as to flow along the vaporized hardening agent supply pipe. They discovered that it was sufficient to use a structure that heated the curing agent, and completed the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the curing agent supply device according to the present invention will be described in detail with reference to the drawings.

Fig. 1 is an explanatory diagram of one embodiment of the curing agent supply device according to the present invention, Fig. 2 is an enlarged end view taken along line A-A in Fig. 1, and Fig. 3 shows another embodiment in Fig. 2. FIG. 3 is an enlarged end view.

In the drawing, 1 is a curing agent 2 that is liquid at around room temperature.
is a hardening agent storage tank that is stored in a liquid state, and this liquid hardening agent 2 is methyl formate. Methyl formate has a very low boiling point of 31.5°C, so it is not suitable for summer use. In order to prevent the temperature from rising above this boiling point, the upper part of the curing agent storage tank 1 is provided with a supply air pressure regulating valve 3, and the pressure is regulated by the compressed air supplied from the compressed air supply pipe 4. is maintained at a constant pressure to prevent boiling, and the temperature of the curing agent 2 is maintained below its boiling point by a cooling coil 5 as required. Reference numeral 6 is a safety valve provided at the upper part of the hardening agent storage tank 1 to prevent the pressure inside the hardening agent storage tank 1 from rising excessively. 7 is a curing agent supply pipe that supplies the curing agent 2 in the curing agent storage tank 1 in liquid form via a curing agent supply valve 8 and a flow rate regulator 9; This is an air supply pipe for supplying compressed air, and the tip of this air supply pipe 10 is connected to the hardening agent supply pipe 7 via the flow rate regulator 9. 13
A heat transfer liquid 14 such as water heated by a heat source 15 (an electric heater in the illustrated embodiment) or antifreeze for automobiles in the case of a cold region is stored inside the heat transfer liquid 14. Heat exchanger tube 16 inside
It is a vaporization heating device that is installed with water immersed in it,
The heat transfer tube 16 receives the compressed air supplied from the air supply pipe 10 whose pressure is adjusted via the supply air pressure regulating valve 11 and the curing agent whose flow rate is adjusted from the curing agent liquid storage tank 1 via the flow rate regulator 9. Its inlet side is connected to the end of the curing agent supply pipe 7 so that the mixture with the curing agent 2 supplied from the supply pipe 7 flows therein. Sand 23 17 is connected to the outlet side of the heat transfer tube 16 and is mixed with a binder and a mixture of the compressed air and the hardening agent 2, which is heated by the vaporization heating device 13 to vaporize the hardening agent 2. This is a vaporized curing agent supply pipe that supplies the vaporized curing agent into the molding container 22 which is molded into a predetermined shape. 18 is a circulation pipe for the heat transfer liquid 14 that connects the vaporization heating device 13 and a position close to the vaporized curing agent supply pipe 17 located immediately in front of the molding container 22; 19 is a circulation pipe disposed in the middle of the circulation pipe 18; The direction in which the heat transfer liquid 14 is circulated by the circulation pump 19 is the direction in which the temperature of the hardening agent 2 immediately before it flows into the molding container 22 is adjusted by the vaporization heating device 13. This is preferable because the temperature can be maintained at approximately the same temperature as the heating temperature, but it is not necessarily limited to this direction. 20 supplies the heat transfer liquid 14 that is circulated by the action of the circulation pump 19 between the outlet side of the heat transfer tube 16 of the vaporization heating device 13 and a position immediately in front of the molding container 22 along the vaporized hardening agent supply pipe 17. This heating tube 20 may be a double tube installed around the vaporized curing agent supply pipe 17 as shown in FIG. The heating tube 20 and the vaporized curing agent supply pipe 17 may be covered with a heat insulating material 21, which is a trace piping type pipe arranged in parallel with the vaporized curing agent supply pipe 17. 22 is a molded container with an upper part 22a
and a lower part 22b. 24 is a vertical movement device, and its piston rod 24a is the first
As shown in the figure, the tube end of the hardening material supply tube 17 is connected to an attached tube end plate 34, and normally this tube end plate 34 is pulled upward from the upper part 22a of the molding container 22, but the hardening material supply tube 17 is The agent is molded into a container 22.
When feeding, the tube end plate 34 is pressed against the upper part 22a of the molding container 22, as shown in FIG. The hardening agent supplied in this state flows down into the sand 23 mixed with the binder in the upper part 22a of the molding container 22, and flows down into the molding container 22.
The sand 23 in the molding container 22 is hardened. Excess curing agent is discharged to the outside of the molding container 22 through a ventilation hole 22ba provided in the bottom plate of the lower part 22b of the molding container 22. 25 is the molded container 2
2 is a conveyor for carrying in and carrying out 2, 26 is a molded container 2
2 and the conveyor 25, and a ventilation hole 22ba provided in the bottom plate of the lower part 22b of the molding container 22.
27 is a door installed at the entrance of the gas processing chamber 26; 28 is a door opening/closing device for opening and closing the door 27; 29 is a gas This is an exhaust duct for discharging the curing agent 2 flowing into the gas processing chamber 26 from a vent hole 22ba that communicates with the processing chamber 26 and is provided in the bottom plate of the lower part 22b of the molding container 22. An exhaust fan 30 is installed in the duct 29. In addition, 31 is a mold model buried in the sand 23 mixed with the binder in the molding container 22.

[Effect]

In the hardening agent supply device according to the present invention having such a structure, the hardening agent 2 is supplied from the hardening agent storage tank 1 in which the liquid hardening agent 2 is stored through the hardening agent supply valve 8 and the flow rate regulator 9. In the process of flowing through the curing agent supply pipe 7 in a liquid state, the supply air pressure regulating valve 1
1 and the compressed air supplied from the air supply pipe 10 via the air supply valve 12 to the vaporization heating device 1.
3 into the heat exchanger tubes 16. In this vaporization heating device 13, a heat transfer liquid 14 stored therein is heated by a heat source 15.
Since the heat transfer tube 16 is installed immersed in the heat transfer liquid 14, the compressed air supplied from the air supply tube 10 flowing inside the heat transfer tube 16 and the hardening agent supply tube 7 are mixed. The mixture with the hardening agent 2 is heated by the heat transfer liquid 14, and the hardening agent 2 is vaporized through the vaporized hardening agent supply pipe 17, and the sand 23 mixed with the binder is shaped into a predetermined shape. It is supplied into a molded container 22 that is being molded. At this time, the heat transfer liquid 14 in the vaporization heating device 13 is transferred to the heat transfer tube 16 of the vaporization heating device 13 by the circulation pump 19.
Since the curing agent flowing inside the vaporized hardening agent supply pipe 17 is caused to flow inside the heating tube 20 along the vaporized hardening agent supply pipe 17 between the outlet side and the position immediately in front of the molding container 22 The curing agent 2 maintains its vaporized state because the heat of the heat transfer liquid 14 flowing through the heating tube 20 is transferred through the vaporized curing agent supply pipe 17 and its temperature does not decrease. The binder flows into the molding container 22 which is divided into upper and lower halves, and hardens the binder mixed with the sand 23 in the molding container 22 to form a casting mold strong enough to withstand use. The surplus hardening agent 2 that is not used to harden the binder is then discharged from the gas processing chamber 2 through the ventilation hole 22ba provided in the bottom plate of the molding container 22.
6 and is discharged through the exhaust duct 29 by the action of the exhaust fan 30.

[Effect of idea]

The curing agent supply device according to the present invention as described in detail above does not mix liquid curing agent with air heated by a heating device in a vaporizer for the first time and vaporize it, as in conventional curing agent supply devices. After mixing the liquid curing agent and compressed air in advance, the mixture is flowed through a heat transfer tube that is immersed in the heat transfer liquid in a vaporization heating device filled with the heat transfer liquid. The vaporized hardening agent is heated to completely vaporize it by heating, and then the outlet of the heat transfer tube is in communication with the molding container in which the sand mixed with the binder is molded into a predetermined shape. When supplying the vaporized hardening agent to the molding container through the supply pipe, the heat transfer liquid is circulated from the vaporization heating device, and the vaporized hardening agent is heated by the heating pipe installed along the supply pipe of the vaporized hardening agent. Because of the structure in which the hardening agent is heated, the vaporized hardening agent is cooled before reaching the molding container, becomes condensed and liquefied, and spreads evenly over the sand mixed with the binder in the molding container. In order to prevent the curing agent from becoming over-distributed, and to prevent the temperature of the vaporized curing agent from dropping like in conventional curing agent supply devices, a complicated method such as arranging a supply pipe for the vaporized curing agent around the heating container of the heating device is required. It has a simple structure that does not require piping, and it is possible to evenly distribute the hardening agent in a vaporized state to the sand mixed with the binder in the molding container, resulting in faster manufacturing. The casting mold has a high strength in which the binder is reliably hardened by the hardening agent, and casting defects are eliminated, and its practical value is very great.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of one embodiment of the curing agent supply device according to the present invention, Fig. 2 is an enlarged end view taken along line A-A in Fig. 1, and Fig. 3 shows another embodiment in Fig. 2. The enlarged end view, FIG. 4, is an explanatory diagram of an example of a conventional curing agent supply device. In the drawings, 1... hardening agent storage tank, 2... hardening agent,
3... Supply air pressure control valve, 4... Compressed air supply pipe, 5... Cooling coil, 6... Safety valve, 7... Curing agent supply pipe, 8... Curing agent supply valve, 9... Flow rate regulator, 10... Air supply pipe, 11... Supply air pressure control valve, 12... Air supply valve, 13... Vaporization heating device, 14... Heat transfer liquid, 15... Heat source, 1
6... Heat exchanger tube, 17... Vaporized hardening agent supply pipe, 1
8... Circulation pipe, 19... Circulation pump, 20 Heating tube, 21... Heat insulating material, 22... Molding container, 22
a...Top part, 22b...Bottom part, 22ba...Vent hole, 23...Sand mixed with binder, 24...
... Vertical movement device, 24a ... Piston rod, 25
...Conveyor, 26...Gas treatment room, 27...
Door, 28...Door opening/closing device, 29...Exhaust duct,
30...Exhaust fan, 31...Mold model, 32...
... vaporizer, 33 ... heating device, 34 ... tube end plate.

Claims (1)

[Claims for Utility Model Registration] 1. A hardening agent storage tank 1 in which a liquid hardening agent 2 is stored, and a heat transfer liquid 14 in a vaporization heating device 13 that is heated by a heat source 15. The curing agent 2 is supplied from the hardening agent storage tank 1 through the flow rate regulator 9 to the heat transfer tube 16 which is immersed in the heat transfer tube 16.
and a curing agent supply pipe 7 that guides a mixture of compressed air from the air supply pipe 10, and the mixture connected to the outlet side of the heat transfer tube 16 and heated by a vaporization heating device 13 to vaporize the curing agent 2. A vaporized hardening agent supply pipe 1 that supplies sand 23 mixed with a binder into a molding container 22 in which the sand 23 is molded into a predetermined shape.
7, a heating tube 20 disposed along the vaporized curing agent supply pipe 17 between the outlet side of the heat transfer tube 16 of the vaporization heating device 13 and a position immediately in front of the molding container 22; A curing agent supply device comprising a circulation pump 19 that returns the heat transfer liquid 14 in the heating device 13 to the vaporization heating device 13 via the heating tube 20. 2. The hardening agent supply device according to claim 1, wherein the heating tube 20 is a double pipe provided around the vaporized hardening agent supply pipe 17. 3. According to claim 1, the heating tube 20 is a tube installed in parallel with the vaporized hardening agent supply tube 17, and the heating tube 20 and the vaporized hardening agent supply tube 17 are coated with a heat insulating agent 21. The curing agent supply device described. 4. The circulation pump 19 first supplies the heat transfer liquid 14 in the vaporization heating device 13 to a position immediately in front of the molding container 22, and then supplies it to the outlet side of the heat transfer tube 16 of the vaporization heating device 13 to the vaporized curing agent supply pipe 17. The curing agent supply device according to any one of claims 1 to 3, which is a circulation pump for causing flow along the curing agent.