JPS5838634A - Method and device for quick dehumidifying and drying of molding sand - Google Patents

Abstract

PURPOSE:To dehumidify and cool molding sand quickly by effective utilization of a slight time zone during processing by applying a heat treatment by a heating medium to the molding sand contained in the working chamber of a treating tank then evacuating the working chamber automatically. CONSTITUTION:The molding sand in a hopper 19 in the upper part of a treating tank 1 is charged at a prescribed rate into the tank 1 by opening a damper 4, and a heating mechanism is operated by the closing signal of the damper 4. Then, a heating medium is supplied into heating pipings 7 to heat the molding sand charged in a working chamber 13 successively. Upon elapsing of the time zone when the molding sand attains a prescribed temp., the heating mechanism stops, and a vacuum mechanism is operated. Then, powerful attraction forces are generated around the fine hole A groups of evacuating pipes 10, and the inside of the chamber 13 is evacuated instantaneously, whereby the molding sand is cooled and dehumidified. When the set time for the evacuation elapses, the ejection of air from air nozzles 5 and the opening of the damper 4a are accomplished simultaneously, and the molding sand is fed to the next stage through a pneumatic pipe 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention rapidly heats, dehumidifies, and lowers the temperature of molding sand used after casting during the casting process, using a short transfer period.

Therefore, the molding sand used for the second and subsequent mold fillings was under extremely poor conditions as it contained high levels of moisture and humidity that had a negative effect on the castings, which in turn led to a high defect rate. This has become a major bottleneck in improving productivity as it has not been possible to suppress this.

This inventor company solved these problems and dehumidified the foundry sand by effectively utilizing the small time period during mold filling and core filling processes. The purpose is to quickly lower the temperature.

This embodiment is intended to utilize the method and apparatus disclosed in the earlier patent application No. 18G144/1982 for multiple purposes, and includes a processing tank equipped with heating piping and vacuum action pipes for dehumidifying and drying foundry sand. Setting 1: In the working chamber of this processing tank,
A hopper equipped with a preheating chamber and a pneumatic pipe of an air conveying line are connected to each other, and the input and discharge ports can be opened and closed by a damper, and the heating medium used for dehumidification is hot air, steam, drought water, electric heater, etc. as appropriate. It is what you use.

Embodiments of the present invention will be described below based on the drawings.

In this embodiment, as shown in FIGS. 1 and 2, the processing tank 1 has a damper 4 connected to an actuating cylinder 8 such as pneumatic or hydraulic pressure at the input port 2 at the top, and compressed air at the negative side. The nozzle 6 is connected to a heating mechanism (not shown) by disposing a discharge port 6 having another damper ILt at the bottom thereof, and the processing tank 1 is further provided with a separate tank having numerous pores on its circumference. The vacuum working tube 10 is spirally wound and installed inside.

The heat medium supplied by the heating mechanism includes hot air, steam,
Flooding or electric heaters are optional.

The vacuum working pipe 10 has its starting end connected to an external vacuum mechanism (not shown), and the discharge pipe 9 is connected to the lower part of the heating pipe 917. The hopper 19 has a double structure and includes a preheat chamber 20, and the preheat chamber 20 and the introduction pipe 8 are connected by a branch pipe 21. The binog conduit 11 includes an air supply pipe 12 leading to the air nozzle b, a vacuum action pipe 10 and an action chamber 1.
The pneumatic pipe 14 is connected to the conduit 17 connecting the pipes 8 and 8 to form the vacuum piping B of the vacuum mechanism (not shown), and the pneumatic pipe 14 has its starting end connected to the discharge port 6 where the damper 4 & is located, and its terminal end connected to the air transport pipe 17. The line leads to the next process (all not shown). The processing tank 1 shown in FIG.
is also connected to the heating mechanism and vacuum mechanism. In addition, when the heating medium uses electric heat, the heating pipe 7
Instead, a heater (not shown) is installed inside the action chamber 18.18 m.

Note that although the embodiments of the present application have been explained only regarding foundry sand,
The symmetry is not limited to foundry sand.

In this invention, by opening the damper 4, a predetermined amount of the foundry sand 18 that has been put into the hopper 19 at the top of the processing tank l shown in FIGS. When closed, the heating mechanism is activated by the signal and supplies a heating medium such as hot air, steam, or hot water to the heating pipe 7. The molding sand 18 charged into the working chamber 18 is successively heated while moving vertically and horizontally within the chamber, and when the heating degree of the molding sand 18 reaches the required temperature, the heating mechanism is stopped and the vacuum is removed. Since the vacuum mechanism is switched on, the vacuum mechanism continues to operate, generating a strong suction force around the pores A group of the vacuum working tube 100, and instantly evacuating the inside of the working chamber 18. During this vacuum action, the high heat and moisture of the foundry sand 18 are sucked out, lowering the temperature of the foundry sand 18 and dehumidifying it, and when the set time of this vacuum action has elapsed, the next operation is started. , the air jet from the air nozzle 5, and the number of turns of Danno <-4g are performed at the same time, so the foundry sand 18 in the working chamber 18 is blown into the pneumatic pipe 14 through the discharge port 6, and is directly transferred to the air conveying line. It is sent to the process all at once. In this case, the additional air introduced into the nozzle conduit 11 leading to the air supply pipe 12 reaches the vacuum working pipe 10, which communicates with the bypass pipe 11 via the conduit 17, and the pipe opening on that side Since air is ejected from the pores into the action chamber 18, all the pores A that are clogged during the vacuum action are opened to prepare for the next vacuum action. During this time, a predetermined amount of air is ejected from the air nozzle b, and the damper 41 is closed in response to a signal indicating the end of the ejection, thereby completing one stroke. During this time, a heating medium is supplied to the residual heat chamber 20 through the branch pipe 21, and the molding sand 18 in the hopper 19 is appropriately warmed by the residual heat. The process of adding a predetermined amount of the liquid is continuously repeated. The processing tank 1a of the side-by-side embodiment also operates in the same manner as described above.

Since the present invention is configured as described above, it has the following advantages.

(1) Since a heating mechanism and a vacuum mechanism are arranged in the processing tank, the molding sand in the processing tank can be dehumidified and the temperature lowered in a short time by heating and vacuum action.

(2) Since the foundry sand is preheated in the preheating chamber, it is possible to dehumidify and lower the temperature by the vaporization effect of the vacuum action in addition to heating the working chamber, which not only saves energy, but also allows the foundry sand to be heated in the next step. By cooling to the optimum temperature for molding, it is possible to significantly reduce the number of defective products during casting.

(8) #The short time period during which the sand is delivered to the next process can be used effectively, and at the same time, the environmental hygiene effect of pneumatic conveyance can be significantly enhanced.

4. The invention of the additional related original patent invention (%Application No. 182144/1983)
The foundry sand that is being used after 6 hours is put into the vacuum tank in which the pneumatic pipe, air nozzle, and hopper of the air conveyance line are arranged, and the molding sand that is being used is placed inside this vacuum tank and is placed inside the vacuum tank, which has countless pores. A vacuum action is applied, and this vacuum action lowers the temperature of the foundry sand.Then, at the same time as the discharge port is opened, the air nozzle jets and the air is reversely jetted through the bypass pipe into the vacuum action pipe, etc. This invention relates to a method and apparatus for rapidly cooling foundry sand by pneumatic conveyance, in which pneumatic conveyance is carried out to the next step through a pneumatic conveyance tube, and at the same time, the operation of eliminating clogging of pores in a vacuum working tube is repeated.
By using a heating mechanism that heats the foundry sand in a processing tank, and a vacuum mechanism that rapidly cools the molding sand heated by this heating mechanism and lowers the temperature at the same time, it is possible to remove the large amount of molding sand that is contained in the foundry sand. This method rapidly eliminates the moisture present in the molding sand and rapidly cools the temperature of the molding sand caused by heating, thereby making it possible to treat the molding sand to the optimum state for casting in a short time. This is what I did.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of an apparatus for carrying out the method of the present invention to Fig. 2 is an enlarged plan view taken along line 2-2 in Fig. FIG. 3 is a vertical cross-sectional view of an example. (Explanation of symbols of main parts) 1.1a---1 processing tank 5-111 air nozzle 6---discharge lo 8----
Heating pipe 11---Bypass pipe 1!3.18a-
--1 working chamber 14---1 blowing pipe 18---1 casting sand 19---hopper 120---1 preheating chamber
A-111 Slipper patent applicant

Claims (1)

[Claims] (υ Foundry sand is stored in the working chamber of a processing tank, the foundry sand is subjected to heat treatment using a heating medium, and after this heat treatment, the working chamber is evacuated to dehumidify the foundry sand and lower the temperature. A method for rapid dehumidification and drying of foundry sand, characterized by automatically performing drying. (2) A heating mechanism, a heating mechanism,
A processing tank is constructed in which a vacuum mechanism and an air conveyance line are respectively arranged, and the heating piping and heating mechanism are connected to the vacuum action pipe and the vacuum mechanism by an introduction pipe and a conduit, respectively. A rapid removal device for molding sand, which is equipped with a hopper having a chamber, and the hopper and air conveyance line are interrupted by a damper.