JP3441603B2 - Asphalt plant elevator chute - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chute provided at an upper discharge port of an elevator (hot elevator) of an asphalt plant.

[0002]

2. Description of the Related Art Drainage mixture, which is a kind of special mixed material used in asphalt plants, is a fine-grained aggregate (5 mm
Since the content of the following) is small, the thermal efficiency at the time of drying and heating with a dryer is low. Therefore, in order to improve the thermal efficiency, the fine-grain-size aggregate is separately supplied into the dryer, and after heating, the fine-grain-size aggregate is extracted and recirculated to the dryer.

FIG. 2 is a block diagram of a conventional asphalt plant. In the figure, 1 is a dryer for drying and heating the supplied aggregate, 2 is an elevator for vertically conveying the aggregate discharged from the discharge port 1B of the dryer 1, and 3 is discharged from an upper discharge chute 5 of the elevator 2. The sieving device 4 for receiving and sieving the aggregates to be sieved is a hot bottle for storing the aggregates sieved by the sieving device 3 according to the particle size.

An aggregate supply conveyor 6 is connected to the inlet 1A of the dryer 1 so that new aggregate is sequentially supplied into the dryer 1. The aggregate passes through a dryer 1, an elevator 2, and a sieving device 3, and then a hot bottle 4
Stored in. Aggregates of useful particle size to be mixed with asphalt are divided into bins 4a and 4b of the hot bottle 4, and useless fine particle aggregates are divided into bottles 4c and 4d.
Then, the fine-granular aggregates divided into the bins 4c and 4d are discharged from the lower part of the hot bin 4, carried to the inlet of the dryer 1 by the circulation conveyor 7, and returned into the dryer 1 via the chute 8.

[0005]

By the way, in the conventional asphalt plant, since the fine-grain aggregate is extracted from the lower outlet of the hot bottle 4, the circulation conveyor is used to recirculate the fine-grain aggregate to the dryer 1. It was necessary to use 7. Therefore, the facility cost is increased and the operation is troublesome.

In consideration of the above-mentioned circumstances, the present invention provides an elevator chute for an asphalt plant in which fine-grained aggregate can be withdrawn from the elevator to the sieving device and returned to the dryer, thereby eliminating the need for a circulating conveyor. The purpose is to provide.

[0007]

According to a first aspect of the present invention, there is provided a dryer for drying and heating the supplied aggregate, and an elevator for conveying the aggregate discharged from the dryer vertically upward.
In the upper discharge port of the elevator of the asphalt plant equipped with a sieving device for receiving aggregate discharged from the upper discharge port of this elevator and a hot bottle for storing the aggregate sorted by the sieving device according to the particle size In the chute provided, in the inclined internal passage through which the aggregate of the chute body passes, with a space from the bottom plate of the chute body, along the main flow direction of the aggregate,
Moreover, a sieving net that allows only the fine-grained aggregate to pass through is attached, and the bottom plate of the sheet body is provided with an outlet for leading out the fine-grained aggregate that has passed through the sieving net to the outside.

According to a second aspect of the present invention, in the first aspect, an opening / closing damper is provided at the outlet.

A third aspect of the present invention is characterized in that, in the first or second aspect, an exciter is attached to the chute main body, and the chute main body is vibratably attached to the elevator casing.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a main part of an asphalt plant provided with a chute 20 of the embodiment, and the chute 20 is shown by seeing through an internal structure.

The chute 20 has a chute body 21 formed in a cylindrical shape. The chute body 21 has a normal shape having an inclined internal passage through which the aggregate passes, and is attached to the upper discharge port of the elevator 2 via a hinge 19 at the upper end so as to be vertically rotatable. Further, the chute body 21 is supported by a spring 31 so as to be vertically vibrable with respect to the casing of the elevator 2 below the upper discharge port. The gap between the upper outlet of the elevator 2 and the chute body 21 is closed by a seal 31 such as a bellows.

The inclined inner passage of the chute body 21 is spaced from the bottom plate 21a of the chute body 21,
A sieving net 22 is attached along the main flow direction of the aggregate and only allows the fine-grained aggregate to pass. Also, the seat body 2
The bottom plate 21a of No. 1 is provided with an outlet 23 for leading out the fine-grained aggregate that has passed through the sieve net 22 to the outside. The outlet 23 is provided with an open / close damper 25 driven and operated by an air cylinder or the like, and a short flow dividing chute 24. A circulation chute 27 is provided below the flow dividing chute 24 to return the fine-grained aggregate derived from the take-out port 23 to the inlet or the central portion of the dryer 1.

The chute 20 in this case is the elevator 2
Since it is installed at a high position called the upper discharge port of the
By connecting to the lower side of 4, the inclination of the circulation chute 27 can be used to directly recirculate the fine-grained aggregate to the dryer 1 by natural flow.

An exciter 30 is attached to the upper part of the chute body 21 so that the chute body 21 can be subjected to vibrations necessary for sieving fine-grained aggregate. Other configurations of this asphalt plant are shown in Figure 2 except that the circulating conveyor is eliminated.
Is the same as the conventional example.

In this plant, the aggregate discharged from the upper discharge port of the elevator 2 is sieved by the sieve net 22 while flowing through the chute body 21. In particular, by vibrating the chute main body 21 with a vibration exciter, sieving is efficiently performed. Then, the fine-grained aggregate that has passed through the sieving net 22 is diverted and collected through the take-out port 23 by opening the damper 25, and returned to the inlet of the dryer 1 or the like through the circulation chute 27. Therefore, since it is not necessary to use a circulating conveyor that needs to be driven, the facility cost can be reduced and the operation can be simplified.

Also, by closing the damper 25, it is possible to discharge the fine-grained aggregate together with other aggregates toward the sieving device 3.

In the above embodiment, the chute body 2
1 is provided with a vibration exciter 30 and the chute body 21 is oscillatably supported by a hinge 19 and a spring 32 (or a vibration isolation support device including a vibration isolation rubber or the like). If the sieving net 22 can be used for sieving naturally, it is not always necessary to adopt those configurations.

[0018]

As described above, according to the invention of claim 1, while the aggregate discharged from the upper discharge port of the elevator flows through the chute, the fine-grain size aggregate is separately collected and discharged from the discharge port. Can be taken out. Since the chute in this case is located at a high position, which is the upper discharge port of the elevator, by directly connecting another circulation chute to the outlet,
The fine-grained aggregate can be recycled directly to the dryer. Therefore, it is possible to recirculate the fine-grained aggregate by simply providing a circulation chute instead of the circulation conveyor, and it is possible to reduce the equipment cost and simplify the operation.

According to the second aspect of the present invention, by opening the damper provided at the outlet, the fine-grained aggregate can be taken out from the outlet, and the fine-grained material can be provided at the inlet side of the dryer or the charging port at the intermediate portion. Aggregate can be charged and recycled. Further, by closing the damper, the fine-grained aggregate can be discharged as it is together with other aggregates toward the sieving apparatus.

According to the third aspect of the present invention, it is possible to efficiently perform the screening of the fine-grained aggregate with the sieving net by the vibration of the exciter provided in the chute body.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a main part of an asphalt plant provided with a chute according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a conventional asphalt plant.

[Explanation of symbols]

1 dryer 2 elevators 3 sieving equipment 4 hot bottles 20 shoots 21 chute body 22 sieve screen 23 Exit 25 Open / close damper 30 shaker

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) E01C 19/02-19/10

Claims (3)

(57) [Claims] 1. A dryer for drying and heating the supplied aggregate, an elevator for vertically conveying the aggregate discharged from the dryer, and a sieve for receiving the aggregate discharged from an upper discharge port of the elevator. In a chute provided at the upper discharge port of the elevator of an asphalt plant equipped with a sieving device and a hot bottle that stores the aggregate sorted by the sieving device according to the particle size, an inclined internal passage through which the aggregate of the chute body passes In addition, at a distance from the bottom plate of the chute body, along the main flow direction of the aggregate, and with a sieve net that passes only fine-grained aggregate, the bottom plate of the sheet body, the fine grain that passed through the sieve mesh An elevator chute for an asphalt plant, which is provided with an outlet for discharging the aggregate to the outside. 2. The elevator chute for an asphalt plant according to claim 1, wherein an opening / closing damper is provided at the outlet. 3. An elevator chute for an asphalt plant according to claim 1, wherein a vibration exciter is attached to the chute body, and the chute body is vibratably attached to the casing of the elevator.