JPH072649Y2 - Sieving and storage equipment for aggregates in asphalt plants - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a sieving storage device for an asphalt plant, which stores heat-dried aggregate by sieving according to particle size.

[Prior Art] In a conventional asphalt plant, as shown in FIG. 3, aggregate dried by heating and drying in a dryer is sieved by a vibrating screen 1 into an aggregate storage bin 2 having a compartment arranged under the vibrating screen 1. It is temporarily stored according to particle size. Then, when manufacturing the asphalt mixture, the discharge gate 3 arranged under the aggregate storage bin 2 according to the composition of the aggregate 3
After opening a, 3b, 3c and 3d, the desired aggregate is discharged and after cumulatively weighed by the weighing hopper 4, it is put into a mixer and molten asphalt, stone powder, etc. are added, and the mixture is adjusted to give a predetermined asphalt mixture. Manufacturing.

By the way, the sieve screen of the vibrating screen 1 is designed to have a smaller mesh as it goes to the lower stage. Normally, the uppermost stage has a sieve mesh 6a with square holes (or round holes) having a mesh size of 30 mm, and the lower stage has a mesh. Sieve mesh 6b with a size of 15 mm, sieve mesh 6c with a mesh size of 6 mm in the lower stage, and sieve mesh with a mesh size of 3 mm in the lower stage
6d is arranged. When the aggregate is sieved by the vibrating screen 1 in which the sieve mesh is arranged in this way, the sand bin 2a of the aggregate storage bin 2 passes through the lowermost sieve mesh 6d of the vibrating screen 1.
Those having a particle size of 2.5 mm or less are stored, and the ones stored in the sand bottle 2a are mixed as sand in the asphalt mixture.

In this way, in the aggregate storage bin of the conventional asphalt plant, since there is only one sand bin in the aggregate storage bin, the supply side distinguishes it from fine sand and coarse sand, but it is supplied to the plant body. Both fine sand and coarse sand are stored together in sand bottles and handled as aggregates of 2.5 mm or less.

[Problems to be solved by the invention] However, in general, when the aggregate is sieved by a vibrating sieve, the aggregate passing through the sieve has a finer grain size on the material input side and a coarser grain size on the discharge side. Things gather.
Therefore, such a particle size distribution also occurs in the sand bottle, and this particle size distribution adversely affects the quality of the asphalt mixture.

In view of the above points, the present invention allows the sand in the aggregate to be classified into two types, and divides the sand bottle into two chambers to store coarse and fine sand particles separately. The purpose is to produce a high-quality asphalt mixture by making it possible.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention stores a vibrating sieve that screens aggregate dried by heating with a dryer according to particle size, and an aggregate sieve screened by the vibrating screen according to particle size. In an aggregate sieving and storing apparatus in an asphalt plant, which comprises an aggregate storage bin having compartments, fine sand screens are arranged in two stages above and below the vibrating screen, and the fine sand screen The lower stage is tilted in the opposite direction to the upper stage, and a guide chute that guides the sand screened by the sieve net to the sand bottle is arranged below the upper fine sand screen, and the sand bottle of the aggregate storage bin is installed. Inside of the aggregate in an asphalt plant, characterized in that the sand bottle is divided into two chambers by arranging a partition plate so that the upper end is located below the lower end of the lower fine sand screen. Provide sieving storage device It is intended for and.

[Operation] In the sieving / storing apparatus for aggregates in the asphalt plant according to the present invention, when the aggregates heated and dried by the dryer are put into the vibrating sieve, the fine-grained sand in the aggregates has a coarse mesh screen. It passes through one after another and falls. Then, the sand that has reached the upper fine sand screen is further sieved, and a part of the fine particles of the sand passes through the screen and drops onto the guide chute. The fine particles of sand that have fallen on the guide chute slide down the chute and are thrown into the sand bin for fine particles that stores the fine particles of the sand bottle from the lower end of the guide chute. In addition, the sand that has not passed through the mesh of the upper fine sand screen moves to the lower fine sand screen that is inclined in the lower direction in the lower direction, and is further sieved while flowing down the lower fine sand screen. The fine sand that has passed through the mesh of the sieve mesh falls and is stored in the fine sand sand bottle. The coarse particles of sand that have not passed through the lower fine sand screen are dropped from the lower end of the lower fine sand screen and stored in the coarse sand bottle. In this way, by arranging two stages of fine mesh for fine sand and increasing the effective length of the sieve mesh, sand with fine grain size and poor sieving efficiency can be sieved as much as possible. In the sand screen for sand, since sand is put in the vicinity of the upper end of the screen, it is possible to effectively use the entire length of the lower screen for fine sand to perform screening.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

11 is a vibrating sieve mounted on the top of the mixing tower of the asphalt plant, and the heated aggregate heated and dried by the dryer is lifted by the vertical transfer device and charged from the charging chute 12, and by the vibration generated by the vibrating body 13. Sifted according to particle size. The vibrating screen 11 is provided with several stages of screen screens, and the screen size and arrangement of this screen screen are the same as the conventional ones. Size 15 mm sieve mesh 11b, mesh size 6 in the lower row
A sieve mesh 11c having a size of 3 mm and a sieve mesh 11d having a mesh size of 3 mm are arranged below the sieve mesh 11c.

An auxiliary vibrating screen 15 having a vibrating body 14 is arranged below the vibrating screen 11, and the sand that has passed through the screen of the vibrating screen 11 having a mesh size of 3 mm is sieved to coarse and fine particles. Divide. The auxiliary vibrating screen 15 is provided with a fine sand screen having a mesh size of 1.5 mm arranged in two stages, and the upper fine screen 15a is inclined in the same direction as the vibrating screen 11. The lower stage fine sand screen 15b is inclined in the opposite direction to the upper stage screen 15a. A guide chute 16 is disposed below the upper fine sand screen 15a for guiding the fine sand screened by the screen 15a into a sand bottle. The guide chute 16 has its lower end tip portion projected from the tip end of the upper fine sand screen 15a and is attached with a cover body 17 so that the sand dropped from the tip of the upper fine sand screen 15a is It drops onto the cover body 17, slides down on the surface thereof, falls near the upper end of the lower fine sand screen 15b, and flows down the screen 15b. The discharge port 18 of the guide chute 16 is located at the same position as or slightly protrudes from the upper end of the lower fine sand screen 15b, and the fine sand discharged from the discharge port 18 by sliding down on the guide chute 16 is in the lower stage. It has a structure that does not fall on the fine sand screen 15b.

Below the vibrating screen 11 and the auxiliary vibrating screen 15, an aggregate storage bin 19 provided with compartments is arranged so that the sieved aggregate can be stored according to particle size. Further, a partition plate 20 is arranged in a sand bottle located below the auxiliary vibrating screen 16 in a direction orthogonal to the flow of aggregates of the vibrating screen 11, and the upper end of the partition plate 20 is a lower fine sand screen. The sand bottle is located in the lower part of the lower end of 15b and is divided into two chambers, and a coarse grain sand bottle 19a for storing coarse grain sand and a fine grain sand bottle 19b for storing fine grain sand are provided. Is forming.

Aggregates having a larger grain size than the sand stored in the coarse-grain sand bottle 19a and the fine-grain sand bottle 19b are sequentially stored in the aggregate bins 19c, 19d, and 19e. 21a, 21b, 21c, 21d and 21e are discharge gates provided at the bottom of each bin.

A sand weighing hopper 22 is disposed below the coarse-grained sand bottle 19a and the fine-grained sand bottle 19b of the aggregate storage bin 19, and the amount of sand mixed in the asphalt mixture is more precisely measured and managed. , To improve the quality. Also aggregate bins 19c, 19
Below the d and 19e, an aggregate measuring hopper 23 similar to the conventional one is arranged, and below the lower part, a material mixing mixer 24 is arranged.

Then, when the aggregate heated and dried by the dryer of the asphalt plant is lifted to the upper part of the mixing tower and charged into the vibrating screen 11 through the charging chute 12, the screen 11a
Screened by ~ 11d one after another. The fine-grained sand in the aggregate successively passes through the mesh of the sieve mesh, and also passes through the sieve mesh 11d having a mesh size of 3 mm at the lowermost stage and reaches the upper fine sand sieve mesh 15a. The sand that has reached the upper fine sand screen 15a is sieved by this screen, and a part of the fine-grained sand passes through the mesh and drops onto the guide chute 14 and slides down on this chute and the discharge port 18
It is dropped and stored in the fine grain sand bottle 19b. on the other hand,
The sand that has flowed down without passing through the mesh of the upper fine sand screen 15a drops onto the cover body 17, slides off the surface thereof, and falls near the upper end of the lower fine sand screen 15b. While flowing down the lower fine sand screen 15b, most of the fine sand is sieved and passes through the mesh, and is dropped and stored in the fine sand bin 19b. The coarse-grained sand that has not passed through the mesh of the lower fine sand screen 15b is dropped from the lower end to the coarse-grain sand bottle 19a and stored.

As a result, 1.2-2.5 mm of coarse-grained sand is stored in the coarse-grained sand bottle 19a, and fine-grained sand of 1.2 mm or less is stored in the fine-grained sand bottle 19b.

Then, when producing an asphalt mixture, a predetermined amount of coarse sand is dispensed from the coarse sand bin 19a according to the composition of the asphalt mixture, and a predetermined amount of fine sand is dispensed from the fine sand bin 19b. The weighing hopper 22 performs cumulative weighing. Further, a predetermined amount of aggregate is dispensed from the aggregate bins 19c, 19d, 19e, weighed by the aggregate weighing hopper 23, dispensed to the mixer 24, and asphalt is sprayed and mixed.

Although the auxiliary vibrating screen 15 is shown as being provided separately from the vibrating screen 11 by providing the vibrating body 14, a vibrating screen dedicated to sand is applied to give vibration suitable for sieving fine sand. It is a separate unit for use and transportation.
The vibrating screen 11 and the auxiliary vibrating screen 15 may be integrally formed by arranging the vibrating screen 11 under the lowermost screen net 11d.

[Advantages of the Invention] In the aggregate sieving / storing device in the asphalt plant according to the present invention, the sand in the aggregate is sieved and stored into coarse-grained sand and fine-grained sand, and therefore the sand particle size control is performed. Can be carried out and the quality of the asphalt mixture can be improved.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view in which a part of an aggregate sieving and storing device according to the present invention is longitudinally cut, and FIG. 2 is a perspective view showing upper and lower fine sand screens and guide chutes of the present device. FIG. 3 is a schematic explanatory view in which a part of a conventional sieving and storing apparatus for sieving aggregate is cut vertically. 11 …… Vibration sieve, 12 …… Injection chute, 11a, 11b, 11c, 1
1d ...... sieve screen, 14 ... guide chute, 15 ... auxiliary vibrating screen,
15a: Upper fine sand screen, 15b: Lower fine sand screen, 16 ...
… Guidance chute, 17… Cover body, 18… Discharge port, 19…
… Aggregate storage bottle, 19a …… Coarse grain sand bottle, 19b …… Fine grain sand bottle, 20 partition plate, 22 …… Sand weighing hopper, 23 …… Aggregate weighing hopper, 24 …… Mixer

Claims (1)

[Scope of utility model registration request] 1. A bone in an asphalt plant, comprising: a vibrating sieve for sieving aggregate dried by heating with a dryer according to particle size; and an aggregate storage bin provided with a compartment for storing aggregate aggregate screened by the vibrating sieve according to particle size. In a material sieving and storage device, a fine sand screen is placed below the vibrating screen to form two upper and lower parts.
A guide chute for arranging the sand in a step, the lower part of the sieve net for fine sand is inclined in the opposite direction to the upper part, and a guide chute for guiding the sand screened off by the sieve net to the sand bottle under the upper part of the sieve net for fine sand. In addition, a partition plate is disposed inside the sand bin of the aggregate storage bin so that the upper end is located below the lower end of the lower fine sand screen and the sand bin is placed in two chambers. Screening and storage equipment for aggregate in asphalt plant characterized by division