JPH046855Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a sand scattering device, and more particularly, to a sand scattering device for uniformly scattering colored sand, etc. on the surface of a molded product in the manufacturing process of inorganic products.

Conventional technology Conventionally, in the manufacturing process of inorganic products such as fiber-reinforced cement building boards or roofing materials, sand grains such as colored sand are sprinkled on the surface of uncured molded products for the purpose of decoration or reinforcement of the product surface. will be carried out.

Since the sand to be spread greatly affects the appearance of the product, it is necessary to strictly control the size of the sand grains and the density of the sand to be spread.

For this reason, the grain size of the sand grains used is strictly adjusted in advance using a sieve, and after drying so that there is almost no moisture, it is placed on the conveyor belt where the uncured product or the product after coating is transferred. A coarse wire mesh is placed between the sand particles being supplied to the hopper and falling from the hopper onto the surface of the product, thereby scattering the sand particles so that they are evenly dispersed and fall.

Conventional Problems However, even if the particle size etc. are strictly controlled as described above, the uncured molded product flowing below the spraying device is a hydraulic substance and contains water, and the product after paint application contains unevaporated solvent, so these evaporated water or solvent
Dew condenses on the wire mesh or hopper opening used to scatter sand grains, making it easier for sand grains to adhere. In particular, there was a problem that if the sand particles adhered to the wire mesh, the sand grains could not be uniformly scattered, making it impossible to obtain a product with a uniform appearance.

For this reason, these sand spreading devices have to be monitored, and the wire mesh has to be replaced frequently, which is a problem in that it is extremely time-consuming.

Problems to be solved by this invention In view of the above-mentioned problems, this invention provides a sand spreading device that is capable of always providing a stable supply of sand and completely preventing sand from adhering to the hopper opening, wire mesh, etc. It was done for that purpose.

Technology that led to solving the problem The sand scattering device of this invention has a roll 1, on which a large number of minute irregularities 1B...1B are formed on the outer peripheral surface 1A, facing the lower slit-shaped opening 2A and rotatably supported. A sand hopper 2 is disposed in a casing 3 that opens downward (arrow X), and a lower opening surface 3A of the casing 3 is covered with a wire mesh 4.
Below the wire mesh 4, sand reflecting plates 6, 6 are provided on the side of the opening surface 3A of the casing 3, and are arranged opposite to each other in an inverted eight shape to narrow the opening surface 3A of the casing. This is characterized in that a heating device 5 is attached, and an air supply port 7 is further provided inside the casing 3.

Example Next, this invention will be explained using examples.

FIG. 1 is a sectional view of an embodiment of this invention, and FIG. 2 is an enlarged perspective view of the main parts of the embodiment.

As shown in Fig. 2, the sand scattering device A of this invention has a roll 1 having a large number of minute irregularities 1B...1B formed on its outer circumferential surface 1A facing a lower slit-shaped opening 2A and rotatably supported. A sand hopper 2 is disposed in a casing 3 that opens only downward (arrow Sand reflecting plates 6, 6 arranged opposite to each other in an inverted eight shape to narrow the opening surface 3A are provided on the opening surface 3A side of the casing 3, and a heating device 5 such as an electric heater is attached to the sand reflecting plates 6, 6. Furthermore, as shown in FIG. 3, the inside of the casing 3B has a large number of pores 7A...
Air supply opening 7, 7 consisting of a T-shaped tube with 7A
is set up and configured. In the above embodiments, a knurled roll (not shown) is used as the roll having a large number of minute irregularities formed on the outer circumferential surface.
You may also use

Further, as the wire mesh 4 in the above embodiment, a wire mesh with a grain size larger than sand grains whose grain size is adjusted in advance is used.

In the figure, 8 is an uncured inorganic product or a molded product after coating, and 9 is a conveyor belt.

Effect Next, the operation of this invention will be explained.

First, sand with adjusted particle size is placed in the sand hopper 2.
For example, sand 20 with a size of 20 to 200 meshes is put in, and then the heating device 5 is made to generate heat, the roll 1 is driven to rotate, and the air supply port 7,
Air is supplied from 7 into the casing 3B.

The amount of sand grains discharged from the sand hopper 2 is adjusted by the unevenness of the outer peripheral surface of the roll 1, and the sand particles fall downward and are scattered by the wire mesh 4. For example, if the sand grains are 20 to 200 meshes, the wire mesh 4 has a mesh size of 12 to 36 meshes. Therefore, the sand grains are uniformly dispersed by collision with the wire mesh 4, and are further reflected by the sand reflecting plates 6, 6. Then, it falls in a uniformly dispersed manner onto the uncured molded product 8 below.

At this time, water or solvent evaporates from the molded product 8, but air is supplied into the casing 3, so air is always supplied from the casing 3B through the opening between the sand reflectors 6, 6. Airflow flows out, and evaporated moisture or evaporated solvent does not flow into the wire mesh 4 directions.

Further, since the sand reflecting plates 6, 6 are provided with the heating device 5, even if evaporated moisture or evaporated solvent enters, dew condensation on the wire mesh 4 is prevented.

Effects This idea is structured as described above, so
Even when sand is being sprinkled onto an uncured or coated inorganic molded product, the evaporated moisture or solvent will never adhere to the wire mesh for scattering sand grains or the hopper opening, resulting in no condensation. This allows the scattering state to be maintained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of this invention, FIG. 2 is an enlarged view of the main part of the embodiment, and FIG. 3 is an enlarged view of another main part of the embodiment.

Claims (1)

[Scope of utility model registration request] A sand hopper 2 is opened downward (arrow The lower opening surface 3A of the casing 3 is covered with a wire mesh 4, and below the wire mesh 4,
The casing 3 includes sand reflecting plates 6, 6 arranged opposite to each other in an inverted eight shape to narrow the casing opening surface 3A.
A sand scattering device characterized in that the sand reflecting plates 6, 6 are provided with a heating device 5, and an air supply port 7 is provided inside the casing 3.