JPH0548066Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a sand drying device used for drying used foundry sand and other sand containing moisture.

Currently, many foundries are using the green molding method, which is inexpensive in terms of productivity and cost. When molding cores in the green molding method, sand to which organic range (furan, phenol, etc.) is added as a binder is often used.

In such a recycling process of foundry sand, it is difficult to recover only the core sand, and conventionally, new sand has been used for the core and the foundry sand has not been recycled.
Therefore, since line sand (green sand) gradually increases, the overflow is discarded. However, recently, the cost of purchasing new sand for core sand has become a non-negligible amount, and the cost of disposing of used core sand has also increased significantly. It has become impossible not to recycle and use them.

As a means of recycling used foundry sand, a dry recycling method is often used. When using this method, it is necessary to dry the foundry sand sufficiently beforehand, since the regeneration effect will be poor if the foundry sand contains a large amount of water.

Conventionally, a horizontal rotating cylinder type (rotary kiln type) is often used as a drying device for such foundry sand, and in addition to this, a stirring type (rapid dryer) is also used in some cases.

[Problem that the invention attempts to solve]

However, both the horizontal rotating cylindrical type and the partially agitated type require a large installation area, and furthermore, they require a conveying device for loading and unloading the foundry sand, resulting in high costs. Moreover, some stirring types had many problems such as severe wear of the stirring blades.

Therefore, the purpose of this invention is to provide a sand drying device that can dry used foundry sand and other moisture-containing sand with high efficiency, has a small installation area, and can be installed at low cost. Our goal is to provide the following.

[Means for solving problems]

The sand drying device of this invention includes a vertical cylindrical body provided with a spiral trough on its inner peripheral surface through which sand moves continuously from the lower end to the upper end, and a vertical cylindrical body provided on the outer peripheral surface of the intermediate part of the cylindrical body. a support frame for vertically supporting the cylindrical body; a spring interposed between the flange and the upper surface of the support frame; and a spring for blowing hot air into the cylindrical body from below the cylindrical body. a cylindrical buffer that is closed at the top and open at the bottom to prevent hot air from blowing through, which is installed inside the cylindrical body at the center of the cylindrical body; a hood having an exhaust pipe provided therein; a thermometer attached to the exhaust pipe for measuring the temperature of the exhaust gas in the exhaust pipe; and a thermometer attached to the outer peripheral surface of the lower part of the cylindrical body, the hood is configured to vibrate the cylindrical body. It is characterized by consisting of a vibration motor for giving

Next, this invention will be explained with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing one embodiment of this invention, and FIG. 2 is a front view.

As shown in FIGS. 1 and 2, in the center of the outer peripheral surface of the cylindrical body 1 whose upper and lower ends are open,
An annular flange 2 is provided, and the cylindrical body 1
is vertically supported within the support frame 3 by attaching its flange 2 to a spring 4 provided on the upper surface of the support frame 3.

The cylindrical body 1 can be slightly moved vertically and horizontally by the expansion and contraction action of the spring 4.

A burner 5 as a hot air supply mechanism and an L-shaped conduit 15 are arranged below the cylindrical body 1, and the hot air from the burner 5 passes through the conduit 15.
It is blown into the interior of the cylindrical body 1 from its lower end.

A spiral trough 6 consisting of a continuous spiral gutter of a predetermined width from the lower end to the upper end is provided on the inner peripheral surface of the cylindrical body 1, and a foundry sand supply port 7 is provided on the lower end side wall of the spiral trough 6. A discharge port 8 is provided in the upper end side wall.

A cylindrical buffer 9, which is closed at the top and open at the bottom, is attached to the center of the cylindrical body 1. As shown in FIG. 1, the ceiling portion of the buffer 9 has an M-shaped cross section, that is, an inverted conical shape. The reason why the ceiling portion of the buffer 9 is formed in this manner is that the shape is difficult to deform due to heating with hot air. Functionally, it may have a disc shape or a regular cone shape. The buffer 9 has the function of preventing a large amount of hot air sent from below the cylindrical body 1 from blowing through at once and allowing the hot air to flow along the spiral trough 6. Without this buffer 9, hot air would blow through, resulting in a significant drop in thermal efficiency.

A hood 16 having an exhaust pipe 10 is provided at the upper end of the cylindrical body 1. 11 is a thermometer for measuring the temperature of exhaust gas in the exhaust pipe 10.

A heat insulating material is wrapped around the outer surface of the side wall 12 of the cylindrical body 1 to prevent heat radiation.

A vibration motor 13 is attached to the lower part of the outer periphery of the side wall 12 of the cylindrical body 1 . Vibration motor 13
vibrates in the direction shown by the arrow in FIG. 2, and together with the expansion and contraction action of the spring 4, gives torsional vibration to the cylindrical body 1.

The foundry sand 14 supplied into the spiral trough 6 from the supply port 7 gradually moves upward along the spiral trough 6 due to the torsional vibration of the cylindrical body 1 and is discharged from the discharge port 8.

[Effect]

Next, the operation of this invention will be explained.

The molding sand 14 supplied into the spiral trough 6 from the supply port 7 is transported to the cylindrical body 1 by a vibration motor 13.
Due to the torsional vibration of the cylindrical body 1, it gradually and continuously moves from the lower end to the upper end along the spiral trough 6 inside the cylindrical body 1, and during this time, the cylindrical body 1 is dried by hot air supplied from below. .

Since the inside of the cylindrical body 1 is at a high temperature due to the hot air flowing from below, the molding sand 14 is sufficiently heated.
Moreover, the water is sufficiently dried until the water evaporates and is discharged from the discharge port 8.

At this time, due to the action of the buffer 9, the hot air does not blow through in large quantities at once, but is trapped in the portion below the buffer 9 inside the cylindrical body 1. Furthermore, since the side wall 12 of the cylindrical body 1 is made of a heat insulating material, the heating efficiency of the molding sand 14 is good.

Furthermore, in the portion of the cylindrical body 1 above the buffer 9, moisture contained in the heated foundry sand 14 is evaporated.

As measured by the thermometer 11, when the temperature of the exhaust gas becomes higher than the set temperature, the burner 5 is stopped, and when it becomes lower than the set temperature, the burner 5 is ignited, and the temperature inside the cylindrical body 1 is automatically adjusted. be controlled.

The device of the invention can also be used as a sand cooler by supplying cold air instead of hot air or by making the spiral trough double-bottomed and passing water through it.

Furthermore, since the device of the present invention has excellent heat resistance, it is extremely effective for transporting high-temperature sand, which has had problems with conventional bucket elevators, which have poor heat resistance. It should be noted that the apparatus of the present invention can of course be used not only for drying used foundry sand but also for drying sand containing moisture.

[Effect of idea]

As explained above, this invention has the following excellent effects.

Since the cylindrical body is vertically long, the installation area is small, so it does not take up much space.

Costs are reduced by eliminating the need for input bucket elevator and discharge bucket elevator equipment, and the installation space required for these is also eliminated, further saving space.

Since the sand moves at a slow speed within the spiral trough, the residence time of the sand within the cylindrical body is long, and since the side walls are made of a heat insulating material, the thermal efficiency is extremely high.

Even powdery materials like sand can be dried without scattering like other dryer types.

Since the sand is moved only by the vibration of the cylindrical body 1, no driving source is required, so maintenance is easy.

It can be used without any problem even if the sand contains lumps.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing one embodiment of this invention, and FIG. 2 is a front view. In the drawings, 1... Cylindrical body, 2... Flange, 3... Support frame, 4... Spring, 5... Burner,
6... Spiral trough, 7... Supply port, 8...
Exhaust port, 9... Buffer, 10... Exhaust pipe, 11
... Thermometer, 12 ... Side wall, 13 ... Vibration motor, 14 ... Foundry sand, 15 ... Conduit, 16 ... Hood.

Claims (1)

[Scope of utility model registration request] a vertical cylindrical body provided with a spiral trough on its inner peripheral surface through which sand moves continuously from its lower end to its upper end; a flange provided on the outer peripheral surface of the intermediate part of the cylindrical body; a support frame for vertical support; a spring interposed between the flange and the upper surface of the support frame; a hot air supply mechanism for blowing hot air into the cylindrical body from below the cylindrical body; A cylindrical buffer with a closed upper part and an open lower part installed in the cylindrical body at the center of the cylindrical body to prevent hot air from blowing through, and an exhaust pipe provided on the upper surface of the cylindrical body. a hood having a hood attached to the exhaust pipe;
a thermometer for measuring exhaust temperature in the exhaust pipe; and a thermometer attached to the lower outer peripheral surface of the cylindrical body.
A sand drying device comprising: a vibration motor for applying vibration to the cylindrical body.