JP2995307B2 - Drying equipment for granular materials using low frequency sound waves - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel drying apparatus for drying a granular material using low frequency sound waves.

[0002]

2. Description of the Related Art As an apparatus for drying a granular material,
Hopper dryers are well known. When a resin material such as resin pellets is fed into a molding machine, this drying device blows hot air to apply preheating to the resin material to promote softening and melting, and simultaneously perform drying. When drying resin material, hot air is blown in a state where resin pellets are stored in the hopper, so a large capacity is required for the hopper, taking up space and increasing the size of the entire drying device. was there.

[0003] Further, since resin pellets are stored in a hopper and dried by blowing hot air from below the hopper, it takes a long time for drying, and drying takes place depending on the vertical position of the resin material in the hopper. There were also problems such as variations in the quality.

Therefore, in order to solve such a problem,
A hopper dryer having a double cylinder structure has been proposed. FIG. 3 shows a conventional hopper dryer having a double-cylinder structure, in which a main body 100 has a large number of small holes 1 for suctioning hot air.
The inner wall 102 having a large number of small holes 102a for hot air suction is concentrically arranged in the outer wall 101 having the outer wall 101a. The tip of the inner wall 102 is connected to an air suction source such as a vacuum pump. Is provided with a band heater 103 around the outside. In this hopper dryer, the resin material 106 stored in the hopper 105 provided on the upper side is fed into the gap between the outer wall 101 and the inner wall 102, and hot air is supplied by the band heater 103 while passing the resin material 106 through the gap. And dry it.

[0005]

However, in such a hopper dryer, since the band heater 103 is provided on the outer periphery of the outer wall 101, if the entire apparatus is to be reduced in size, the outer wall 101 and the inner wall 102 are required. And the gap between the resin pellets becomes smaller, and the storage tank for resin pellets becomes smaller. Further, in such a structure, since the band heater 103 is a structure positioned outside, it is difficult to disassemble and clean, especially when the resin material is frequently replaced. Met. Further, it has been pointed out that such a drying apparatus should be improved in terms of thermal efficiency because a certain heat flow is applied to the resin material stored in the material storage hopper for drying. The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a drying apparatus having a simple structure and capable of dramatically increasing drying efficiency.

[0006]

According to a first aspect of the present invention, there is provided an apparatus according to the present invention , comprising a bottom plate having a vent hole, a heat inlet for receiving a heat flow, and a heat exhaust port. a material reservoir tank, it and a heat source for supplying heat flow through the heat inlet of the material reservoir, the bottom of the bottom plate of the material reservoir tank to form a waveguide section, it is housed in the material reservoir tank A low-frequency sound source that supplies low-frequency sound waves to the granular material is attached to the other end of the waveguide, and
The heat flow inlet is provided at an appropriate position in the waveguide section, and the granular material is dried by passing a heat flow while applying a low-frequency sound wave to the granular material layer. The present invention device which is proposed in claim 2, said waveguide portion
Has an elbow-shaped portion.
In the invention device proposed in claims 1 and 2, the low-frequency sound wave may be applied from above, below, or both of the granular material layer . The apparatus of the present invention proposed in claim 3 is configured such that a stirring blade for stirring the granular material is further provided in the material storage tank.

[0008]

According to the apparatus of the present invention, since a low-frequency sound wave is applied to the granular material and a heat flow is conducted for heat exchange, the low-frequency sound wave is transmitted into the material storage layer. As a result, the air in the granular material layer vibrates upon receiving the vibration energy of the low-frequency sound wave, and dramatically increases the contact with the heat flow supplied from the heater unit. In addition, heat exchange can be performed quickly and efficiently.
Further, a heat flow is supplied to the granular material layer by the heater,
The heat flow containing moisture after ending the heat exchange through the granular material layer is pushed out from the exhaust pipe by the dried heat flow supplied from below the granular material layer, and is discharged to the atmosphere as exhaust, By performing the above-described repetition, the heat exchange by the heat flow is performed, and the granular material is dried.

The apparatus of the present invention is particularly useful for a light-granular material having a low specific gravity, which is scattered by a heat flow in a normal heat flow replacement. When the drying is performed by forcibly vibrating up and down, more rapid drying is possible while suppressing the heat flow to such an extent that the powdery material is not scattered. In addition, the device of the present invention
According to this, since low-frequency sound waves can be added to the granular material layer from below the granular material and dried, the space below the material storage tank can be effectively used as a waveguide for the low-frequency acoustic waves, and the compactness can be reduced. A simple drying apparatus can be obtained.

[0010]

PREFERRED EMBODIMENTS Referring to the accompanying drawings below, along with examples of the present invention apparatus, the present invention will be described in detail. FIG.
It is a drying apparatus A according to the present invention. This drying device A is provided with an exhaust pipe 1a opened upward to the atmosphere as a heat exhaust port,
A material storage tank 1 provided with a heat flow inlet 1b provided below an air-permeable bottom plate 2 and connected to an air supply pipe 3a of a heater 3 serving as a heat source.
have. A low-frequency oscillator 4 serving as a low-frequency sound source is attached below the material storage tank 1 via a waveguide 1c. Here, the low frequency oscillator 4, a sound source for generating the following low-frequency sound waves 50Hz containing inaudible sound waves band is preferably used, very low-frequency sound waves generated from here, guide
It is added to the granular material 5 laminated on the upper surface of the bottom plate 2 through the wave tube portion 1c. Further, the heater 3 supplies a heat flow having an air volume adjusted so that dust does not float upward when the heat flow is applied to the granular material 5. The flow rate of this heat flow varies depending on the granular material to be dried, but it is sufficient to use dehumidified air or the like in order to increase the drying exchange rate, and when the granular material 5 is scattered by the added heat flow. , A bag filter may be attached to the exhaust pipe 1a.

The bottom plate 2 in the material storage layer 1 is provided with a ventilation hole 2a for allowing only the heat flow supplied from below to pass upward without dropping the granular material 5 to be laminated on the upper surface thereof. As such a bottom plate 2, a woven wire mesh, a ceramic perforated plate, or the like can be used. Further, the granular material 5 laminated on the upper surface of the bottom plate 2 is caused to vibrate up and down due to the vibration received by the air in the material storage tank 1 when the low frequency oscillator 4 is driven, thereby generating heat flow. It is desirable to adjust the layer thickness to such an extent that the contact efficiency of the material is increased. However, when the amount of the powdery material 5 to be dried in the material storage tank 1 increases and the material layer becomes thicker, A configuration may be adopted in which a stirring blade is provided to uniformly stir the granular material 5. In addition, 1d is an inlet for the powder material, but the material outlet is not shown in the figure.

FIG. 2 shows that a stirring motor 6 is mounted on the upper surface of the material storage tank 1, and a rake-shaped stirring blade 6 b is mounted on a rotating shaft 6 a of the stirring motor 6, and a heat flow is supplied to the granular material 5. During the rotation, the supply of the low-frequency sound waves to the granular material 5 is made uniform by rotating the stirring motor 6. According to such a configuration in which the stirring blades are provided, the throughput of the granular material to be dried can be increased, and the throughput of the drying device A can be increased. In this example, an elbow-shaped waveguide portion 1c 'is provided below the material storage tank 1, and the supply efficiency of low-frequency sound waves is increased by the elbow-shaped waveguide portion 1c'. . In FIG. 2, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. Such an apparatus of the present invention can uniformly and quickly dry resin pellets, powder materials, and the like, but can remove powder materials having a low specific gravity that can be scattered by replacement with a normal heat flow. In other words, the heat flow is conducted while the material itself moves up and down due to the low-frequency sound waves, and the degree of contact between the granular material and the heat flow is drastically increased, so that drying with high drying efficiency is realized.

[0013]

According to the apparatus of the present invention, since a low-frequency sound wave is applied when a heat flow is passed through the granular material, the contact between the granular material and the heat flow is remarkably promoted. The powder material can be dried quickly and efficiently.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of a drying apparatus of the present invention.

FIG. 2 is a longitudinal sectional view of one embodiment of the drying device of the present invention.

FIG. 3 is an explanatory view of a vertical cross-sectional structure of a conventional hopper dryer having a double cylinder structure.

[Explanation of symbols]

 A: Drying device of the present invention 1 ... Material storage tank 1a ... Heat exhaust port 1b ... Heat inlet 1c, 1c '...Waveguide section  2 bottom plate 2a vent hole 3 heat source 4 low frequency sound source

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // B29B 9/16 B29B 9/16 (72) Inventor Joji Senba 1-28-1204 Arima 1-2-chome, Miyama-ku, Kawasaki-shi, Kanagawa 56) References JP-A-60-161740 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F26B 3/36 F26B 3/04 F26B 19/00

Claims (3)

(57) [Claims] 1. A heat sink for receiving a heat flow from a bottom plate having perforated holes.
And a material storage tank having a heat exhaust port, and a heat flow supplied through the heat inlet of the material storage tank.
Heat sourceEquipped with  Below the bottom plate of the material storage tankForming a waveguide section,the above
A low-frequency sound wave is applied to the granular material stored in the material storage tank.
Low frequency sound sourceIs attached to the other end of this waveguide section.
Wherein the heat inlet is provided at an appropriate position of the waveguide section.
Characterized byDrying equipment for granular material. 2. The apparatus according to claim 1, wherein said waveguide portion has an elbow-shaped portion.
The granular material according to claim 1, wherein
Drying equipment. The method according to claim 3, wherein said material reservoir tank, according to claim 1 also has further provided a configuration the stirring blade for stirring the powdered or granular material layer
3. The apparatus for drying a granular material according to any one of 2.