JP2770005B2 - Dry crushed sand manufacturing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for producing dry crushed sand for dry crushed sand used as fine aggregate of construction materials, and more particularly to a crushed crushed crushed sand crushed using a crusher for sand crushing. The present invention relates to a dry crushed sand production method and an apparatus for sieving materials to obtain crushed sand having a predetermined particle size.

[0002]

2. Description of the Related Art Conventionally, as a dry crushed sand manufacturing apparatus of this type, as shown in FIG. 4, for example, a hopper 32 for accommodating a raw material 31a and a raw material 31 composed of oversized particles 31b returned from a sieve described later is used. A sand crusher 34 for crushing the raw material 31 cut out from the hopper 32 through the feeder 33, and a cone crusher 34.
35, which sieves the crushed product from the crushed product into granules having a particle size exceeding the set particle size and particles having a particle size smaller than the set particle size, and the hopper 32
And a classifier 39 such as an air separator for classifying the fine powder 37 from granules having a particle size equal to or smaller than a set particle size to obtain crushed sand 38. In FIG. 4, reference numeral 40 denotes an ore supplying means such as a conveyor for supplying an ore 31a as a raw material 31 to a hopper 32. In the dry crushed sand manufacturing method, the raw material 31 cut out from the hopper 32 through the feeder 33 is crushed while compressing using the cone crusher 34 using the dry crushed sand manufacturing apparatus, and the crushed product is sieved with the sieve 35. The particles are classified into particles larger than the set particle size, for example, a particle having a particle size exceeding 5 mm and a particle having a particle size smaller than the set particle size.
6, the powder is returned to the hopper 32 and crushed again as the raw material 31, and fine particles 37, for example, 10
In this method, a desired crushed sand 38 is obtained by separating a mesh having a size of 0 mesh or less by a classifier 39.

[0003]

However, in the conventional method for producing dry sand and the apparatus therefor, as shown in FIG. 5, the particle size distribution of the corn crusher product (indicated by the hatched frame in FIG. 5) is 0.15. In the area of ~ 1.2 mm, the grain size distribution of the crushed sand specified by JIS A5004 (indicated by a white frame in FIG. 5) is used.
There is a problem that the distance is greatly deviated in a portion exceeding mm.
In addition, the raw material and the oversized granules contained in the hopper are unevenly distributed, and the feed size of the raw material cut out by the feeder is not stable, so that the FM value (coarse particle ratio) becomes unstable, and the performance rate is reduced. Since it is low, there is a problem in that the grain size is bad due to the unstable feed size. Accordingly, an object of the present invention is to provide a dry crushed sand manufacturing method and apparatus capable of obtaining crushed sand having a particle size distribution specified by JIS. Another object of the present invention is to provide a method for producing dry sand and an apparatus therefor capable of stabilizing the FM value and improving the grain shape in addition to the above objects.

[0004]

In order to solve the above-mentioned problems, a first method for producing dry crushed sand of the present invention is to crush raw materials cut out from a hopper using a cone crusher, and then to crush products in two stages. Sieving to exceed the set particle size range,
The particles having the set particle size range and the particles having a particle size smaller than the set particle size range are sieved, and the particles having a particle size exceeding the set particle size range are returned to the hopper, and the particles having the set particle size range are converted into the hopper and the particles having a particle size smaller than the set particle size range at a required ratio. Distribute. The second dry crushed sand production method is characterized in that, in the first method, the granules returned to the hopper and having a particle size exceeding a predetermined particle size range and a predetermined particle size range are mixed with the raw stone at an outlet of the hopper. In the third dry crushed sand production method, after the raw material cut out from the hopper is crushed by using a cone crusher, the crushed product is sieved in three stages, and the crushed product exceeds the set particle size range, the set particle size range, and the coarse size less than the set particle size range. The granules and the granules having a particle size smaller than the set particle size range are sieved and returned to the hopper, and the granules having the set particle size range are returned to the hopper at a required ratio. The method is characterized in that coarse particles having a size smaller than the set particle size range are distributed to the hopper and fine particles having a size smaller than the set particle size range at a required ratio. A fourth dry crushed sand manufacturing method according to the third method, wherein coarse particles having a particle size exceeding the set particle size range, a set particle size range, and a particle size smaller than the set particle size range returned to the hopper are mixed with the rough stone at the outlet of the hopper. It is characterized by doing. On the other hand, the first dry crushed sand manufacturing apparatus of the present invention comprises a hopper for accommodating the raw material, a crusher for crushing the raw material cut out from the hopper, and a crushed product from the corn crusher. A two-stage sieve for sieving particles having a particle size smaller than the set particle size range, a returning means for returning particles having a particle size larger than the set particle size range to the hopper, and a hopper and a particle having a particle size smaller than the set particle size range in a required ratio. Distributing means for distributing to the body. In the second dry sand crushing apparatus, in the first apparatus, the hopper is coaxially inserted so as to extend to an outlet in the outer box for accommodating the ore, and to the outlet of the outer box. And a cylindrical inner box accommodating the particles of the above. The third dry crushed sand manufacturing apparatus includes a hopper for storing the raw material, a crusher for crushing the raw material cut out from the hopper, and a crushed product from the corn crusher.
Requires a three-stage sieve for sieving coarse and small particles smaller than the set particle size range, return means for returning particles larger than the set particle size range to the hopper, and particles in the set particle size range. A first distributing means for distributing the hopper and fine particles having a particle size smaller than the set particle size range at a ratio of: And a second distribution means for distributing at a ratio. A fourth dry crushed sand manufacturing apparatus is the same as the third apparatus, wherein the hopper is coaxially inserted into the outer box containing the raw stone and extends into the outer box so as to extend to the outlet thereof. And a cylindrical inner box for accommodating coarse-grained particles smaller than the range and the set particle size range.

[0005] Here, the raw material refers to a rough stone having a particle size of 20 to 50 mm, a granule returned to the hopper exceeding the set particle size range and a set particle size range, or a coarse particle exceeding the set particle size range and less than the set particle size range. (Hereinafter the same). The set particle size range refers to a particle size range of 2.5 to 5 mm in the particle size distribution of the crushed sand specified by JIS,
The coarse particles having a particle size smaller than the set particle size range mean a particle size of 1.2 to 2.5 mm in the same particle size distribution (hereinafter, the same).
The distribution at a required ratio means that, among the corn crusher products, granules having a particle size that deviates from the particle size distribution of the crushed sand specified in JIS are less than the hopper and the set particle size range so as to satisfy the particle size distribution of the crushed sand specified in JIS. (Hereinafter the same). On the other hand, the crushing of the raw material by the cone crusher is preferably performed not only by compression crushing but also by compound crushing involving bending shear action and crushing between high-density particles. Further, the fine particles having a mesh size of 100 mesh (0.15 mm) or less are classified into particles having a size of less than 100 mesh (0.15 mm) by a classifier such as an air separator.
It is preferable to remove a required amount so as to conform to the particle size distribution specified by IS.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing a first embodiment of the dry crushed sand production apparatus according to the present invention. In the figure, reference numeral 1 denotes a hopper for accommodating a raw material 3 composed of a raw stone 3a supplied by a raw stone supply means 2 such as a belt conveyor and granules 3b exceeding a set particle size range returned from a two-stage sieve by a return means as described later. This hopper 1 is a rough stone 3a
And a cylindrical inner box 1b which is coaxially inserted into the outer box 1a so as to extend to its outlet 4 and accommodates particles 3b and the like exceeding a set particle size range. I have. Below the outlet 4 of the hopper 1, a feeder 5 such as a vibrating feeder for cutting out the raw material 3 is provided. Reference numeral 6 denotes a cone crusher for crushing the raw material 3 supplied through the feeder 5. The cone crusher 6 has a sharp groove and a special groove on the crush surface of the cone cave, and a sharp groove on the crush surface of the mantle. With a twisted soft cast-in groove,
Also, the crushing chamber formed by the cone cave and the mantle is shaped such that its center line is almost vertical at the inlet, the inclination angle gradually changes, and the angle becomes a predetermined angle at the outlet, thereby compressing and crushing the raw material 3. In addition to the crushing, the crushing is performed in combination with the bending and shearing action, and the crushing is performed between the high-density particles. Reference numeral 7 denotes a two-stage sieve such as a vibrating sieve for sieving the crushed product from the cone crusher 6 into granules having a particle size exceeding the set particle size range, a set particle size range, and a particle size smaller than the set particle size range. 4-5 mm first sieve mesh 7a and eye opening 2-3
mm second sieve mesh 7b. And two-stage sieve 7
The granules 3b exceeding the set particle size range, which have been sieved in the above, are returned to the inner box 1b of the hopper 1 by return means 8 such as a belt conveyor.
In addition, the granules 3c in the set particle size range are combined with the granules 3d smaller than the set particle size range by crushed sand as a product to be described later.
The particles are distributed to the hopper 1 and the particles 3d having a particle size smaller than the set particle size at a required ratio by an appropriate distribution unit 9 so as to have a particle size distribution defined by IS. Reference numeral 10 denotes a mixture of granules having a particle size smaller than the set particle size range, which is a product under the sieve of the two-stage sieve 7, and granules having the set particle size range from the distributing means 9, so as to have a particle size distribution defined by JIS. .15 mm) or less fine powder 1
This is a classifier such as an air separator for removing a required amount of 1 and obtaining a desired crush 12.

In order to produce the crushed sand using the dry crushed sand production apparatus having the above-described configuration, first, the raw material 3 cut out from the hopper 1 via the feeder 5 is guided to the cone crusher 6 to be crushed. At this time, the raw material 3 cut out from the hopper 1
The ore 3a stored in the outer box 1a by the ore supply means 2 and the granules 3b exceeding the set particle size range stored in the inner box 1b by the return means 8 from the two-stage sieve 7 are mixed at the outlet 4 of the hopper 1. Since they are mixed, the feed size becomes stable. Next, the crushed product from the cone crusher 6 is sieved by the first and second sieve nets 7a and 7b of the two-stage sieve, and the granules 3b, 3c and 3d exceeding the set particle size range, the set particle size range, and less than the set particle size range. The granules 3b exceeding the set particle size range are returned to the inner box of the hopper 1 by the return means 8 and reused as the raw material 3, and the granules 3b within the set particle size range
c is distributed to the hopper 1 and the granules smaller than the set particle size range by the distribution means 9 at a required ratio that satisfies the particle size distribution of the crushed sand specified by JIS together with the granules 3d whose part (for example, 7% by weight) is smaller than the set particle size range. Distribute to 3d. By returning the granules 3b exceeding the set particle size range to the hopper 1 and distributing the granules 3c having the set particle size range to the hopper 1, the particle size configuration of the raw material 3 is improved, and the raw material 3 in the cone crusher 6 is improved.
And the high-density particle crushing in the cone crusher 6 can be performed, the particle shape of the crushed product can be improved, and the particle size distribution of the sieved product can be adjusted. Thus, the particle size distribution of the crushed sand as a product can be adapted to that specified by JIS. Next, the granules 3d below the set particle size range to be sieved and the granules 3c having a set particle size range distributed thereto are classified by the classifier 10,
A required amount (for example, 60% by weight) of the fine powder 1 is adjusted so that the fine powder 11 having a mesh size or less conforms to the particle size distribution specified by JIS.
When 1 is removed, the desired crushed sand 12 is obtained.

FIG. 2 is a schematic view showing a second embodiment of the dry crushed sand manufacturing apparatus according to the present invention. This dry crushed sand manufacturing apparatus performs sieving of the crushed product of the cone crusher 6 by using a first sieve mesh 13a having an opening of 4 to 5 mm, a second sieve mesh 13b having an opening of 2 to 3 mm, and an opening of the mesh. 1-1.
The crushed product is passed through a three-stage sieve 13 such as a vibrating sieve having a third sieve screen 13c of 5 mm, and the crushed product is set over a set particle size range, set particle size range, coarse particles smaller than the set particle size range and fine particles smaller than the set particle size range While the particles 3b having a particle size exceeding the set particle size range are returned to the inner box 1b of the hopper 1 by the return means 8, and the particles 3c having the set particle size range are separated.
The hopper 1 and the hopper 1 are mixed with the hopper 1 at a required ratio by an appropriate first distributing means 14 so that the crushed sand as a product has a particle size distribution of the crushed sand specified by JIS together with the fine particles 3f smaller than the set particle size range. Less than 3g of fine particles,
In addition, the coarse particles 3e having a particle size smaller than the set particle size range and the fine particles 3f having a particle size smaller than the set particle size range are appropriately distributed by the second distributing means 15 so that the crushed sand as a product has a particle size distribution of the crushed sand specified by JIS. At a required ratio, the hopper 1 and the fine particles 3f smaller than the set particle size range are distributed. The other configuration is the same as that of the first embodiment, so that the same components and the like are denoted by the same reference numerals and description thereof is omitted. Therefore, in the dry crushed sand manufacturing apparatus having the above configuration, the particle size configuration of the raw material 3 becomes more dense.
The particle size of the crushed product can be further improved. In addition, since the particle size distribution of the sieved product is further finely adjusted, the particle size distribution of the crushed stone as a product can be further adapted to that specified by JIS.

Here, the particle size distribution of the crushed product by the cone crusher 6 is as shown in FIG.
In the case where the granules having a grain size of 0.3 to 0.6 mm in the portion following the grain size distribution of the crushed sand specified by JIS are similar to those having a grain size of 0.3 to 0.6 of the crushed sand specified by JIS. Those with other particle sizes are as shown in FIG.
5-5 mm, particle size 1.2-2.5 mm and particle size 0-0.
It can be seen that the amount of the 15 mm granules deviates from the pulverization specified in JIS. Therefore, the opening of the first sieve net 13a of the three-stage sieve 13 in the above-mentioned dry crushed sand manufacturing apparatus is set to 5 m.
m, the mesh size of the second sieve mesh 13b is 2.5 mm, and the mesh size of the third sieve mesh 13c is 1.2 mm, and among the granules having a grain size of 2.5 to 5 mm corresponding to the granules in the set grain size range. 93%
Is returned to the hopper 1 and the remaining 7% is distributed to granules having a particle size of 1.2 mm or less corresponding to fine granules having a particle size smaller than the set particle size range, and corresponds to coarse particles having a particle size smaller than the set particle size range. 50% of the granules having a grain size of 1.2 to 2.5 mm are returned to the hopper 1, and the remaining 50% is distributed to granules having a grain size of 1.2 mm or less. 2.5m
of fine powder of 100 mesh or less
When% was removed by classification, crushed sand having an FM value of 2.79 was obtained, and the grain shape was a rounded cube.

[0010]

As described above, according to the first method for producing dry crushed sand of the present invention and the apparatus therefor, the particle size distribution of the sieved product is adjusted according to the particle size distribution of the crushed product of the cone crusher. Therefore, the particle size distribution of the crushed sand as a product can be adapted to that specified by JIS. Second
According to the dry crushed sand production method and the apparatus thereof, in addition to the effects of the first dry crushed sand production method and the apparatus, the raw material cut out from the hopper and the granules in the set particle size range are mixed at the outlet, and the feed size is reduced. Since it is stable, the FM value of the crushed sand can be stabilized, and the particle size composition of the raw material is good, so that the crushed sand can have a good grain shape. According to the third method for producing dry sand and its apparatus,
Since the particle size distribution of the sieved product is adjusted more closely, the particle size distribution of the crushed sand as a product can be further adapted to that specified by JIS. Further, according to the fourth method for producing dry sand and its apparatus, the feed size is stabilized in addition to the effects of the third method for producing dry sand and its apparatus, so that the FM value of the crushed sand can be stabilized. Since the particle size composition of the raw material is further improved, the grain shape of the crushed sand can be further improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a first embodiment of a dry crushed sand manufacturing apparatus according to the present invention.

FIG. 2 is a schematic view showing a second embodiment of the dry crushed sand manufacturing apparatus according to the present invention.

FIG. 3 is an explanatory diagram of an operation of the dry crushed sand manufacturing apparatus of FIG. 2;

FIG. 4 is a schematic view of a conventional dry-type crushed sand manufacturing apparatus.

FIG. 5 is an explanatory view of the operation of the dry crushed sand manufacturing apparatus of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hopper 1a Outer box 1b Inner box 3 Raw material 3a Rough 3b Granules exceeding a set particle size range 3c Granules in a set particle size range 3d Particles below a set particle size range 3e Coarse particles below a set particle size range 3f Set particle size range Granules of fine particles less than 6 Corn crusher 7 2nd sieve 7a 1st sieve 7b 2nd sieve 8 Return means 9 Distributing means 13 3rd sieve 13a 1st sieve 13b 2nd sieve 13c 3rd sieve 14 First distributing means 15 Second distributing means

Claims (8)

(57) [Claims] 1. A raw material cut out from a hopper is crushed using a corn crusher, and the crushed product is sieved in two stages to be classified into particles exceeding a set particle size range, a set particle size range, and less than a set particle size range. A method for producing dry sand crushed sand, wherein the granules having a particle size exceeding the set particle size range are returned to the hopper, and the granules having the set particle size range are distributed at a required ratio to the hopper and the particles having a particle size smaller than the set particle size range. 2. The method for producing dry crushed sand according to claim 1, wherein the particles returned to the hopper and having a particle size exceeding a predetermined particle size range and a set particle size range are mixed with the raw stone at an outlet of the hopper. 3. A raw material cut out from a hopper is crushed using a cone crusher, and the pulverized product is sieved in three stages to exceed a set particle size range, a set particle size range, a coarse particle less than a set particle size range, and a set particle size. Particles smaller than the specified range are sieved and returned to the hopper.Particles in the specified range are distributed to the hopper and fine particles smaller than the set range at the required ratio. And distributing coarse particles having a particle size smaller than a set particle size range to a hopper and fine particles having a particle size smaller than the set particle size range at a required ratio. 4. The method for producing dry crushed sand according to claim 3, wherein coarse particles having a particle size exceeding the set particle size range, a set particle size range, and less than the set particle size range returned to the hopper are mixed with the rough stone at an outlet of the hopper. . 5. A hopper for accommodating a raw material, a crusher for crushing the raw material cut out from the hopper, and a crushed product from the corn crusher are sieved to particles having a particle size exceeding a set particle size range, a set particle size range, and less than a set particle size range. A two-stage sieve for separating, a returning means for returning particles having a size larger than the set particle size range to the hopper, and a distributing means for distributing particles in the set particle size range to the hopper and particles having a size smaller than the set particle size range at a required ratio. Dry crushed sand production equipment characterized by the above-mentioned. 6. An outer box in which the hopper stores a rough stone,
Coaxially inserted into the outer box to extend to its exit,
6. The dry crushed sand production apparatus according to claim 5, further comprising: a cylindrical inner box that accommodates particles having a particle size exceeding the set particle size range and the set particle size range. 7. A hopper for accommodating a raw material, a cone crusher for crushing the raw material cut out from the hopper, and a crushed product from the corn crusher, wherein coarse particles having a particle size exceeding a set particle size range, a set particle size range, and a particle size smaller than the set particle size range are set. A three-stage sieve for sieving fine particles having a particle size smaller than the particle size range, a return means for returning particles having a particle size exceeding the set particle size range to the hopper, and a hopper having a required ratio of particles having the set particle size range and less than the set particle size range First distributing means for distributing the fine particles to the fine particles, and second distributing means for distributing coarse particles having a size smaller than the set particle size range to the hopper and fine particles having a size smaller than the set particle size at a required ratio. A dry-type crushed sand manufacturing apparatus, comprising: 8. An outer box in which the hopper stores a rough stone,
Coaxially inserted into the outer box to extend to its exit,
The apparatus for producing dry crushed sand according to claim 7, further comprising: a cylindrical inner box that accommodates coarse particles that are larger than the set particle size range, smaller than the set particle size range, and smaller than the set particle size range.