JPH0446831B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a bottom structure of a silo for granular materials such as flour, grains, and chemical powders, and more specifically, to The present invention relates to a bottom structure that can reduce the amount of powder remaining on a silo bottom plate by sequentially filling a plurality of annular bags with gas from the outside to the inside.

[Conventional technology and its problems]

As shown in FIG. 2, the bottom structure of a conventional silo for powder and granular materials includes a cylindrical side wall 2, a funnel-shaped bottom plate 6 with a discharge port 4 in the center, and a center plate corresponding to the discharge port 4. The sheet member 8 has a mouth and is disposed on the bottom plate 6. The sheet member 8 has an outer peripheral edge 10
is airtightly fixed to a position higher than the mounting position of the bottom plate 6 on the side wall 2, the inner circumferential edge portion 12 is airtightly fixed to the upper surface around the outlet 4 of the bottom plate 6, and the intermediate annular portion 14 of the sheet member 8 is fixed airtightly. is airtightly fixed in place on the bottom plate 6.

The present bottom structure further includes a sheet member 8 between the outer peripheral edge 10 and the intermediate annular portion 14, and a first pipe 22 communicating with the outer annular bag 20 formed by the bottom plate 6 and the side wall 2. , has a second pipe 26 that communicates with an inner annular bag body 24 formed by the sheet member 8 between the intermediate annular portion 14 and the inner peripheral edge portion 12, and the bottom plate 6. The first pipe 22 is the first control valve 2
8 to a source of compressed air (not shown);
The second pipe 26 also communicates with the compressed air source via a second control valve 30.

In the above configuration, when the granular material in the silo is discharged from the discharge port 4 by gravity and a certain amount of granular material remains on the sheet member 8, first, the first valve 28 is released. The outer annular bag 20 is filled with compressed air so that the portion of the sheet member 8 forming the outer annular bag 20 is at the position shown by the dotted line 8.1 in FIG. As a result, the outer annular bag body 2
Most of the powder on top of the inner annular bag 24
Move up.

Subsequently, the second valve 30 is released to fill the inner annular bag body 24 with compressed air, and the portion of the seat member 8 that forms the inner annular bag body 24 is indicated by the dotted line 8 and 2 in FIG.
Position it as shown in . As a result, much of the powder and granular material on the inner annular bag body 24 falls into the discharge port 4, but the outer peripheral portion 11 of the inner annular bag body 24 and the sheet member around the discharge port 4 still remain. 8
There was a problem in that the powder remained in a considerable thickness on the fixed edge 12 which was the fixed part to the bottom 6 of the container.

[Object of the present invention]

The present invention has been made in view of the above-mentioned problem of the bottom structure of a conventional silo for powder and granular materials, and is designed to provide a solution to the problem that when the granular material in the silo is discharged from the discharge port, the powder and granular material remains at the bottom of the silo. The purpose is to provide a bottom structure with low volume.

Another object of the present invention is to provide a bottom structure that can reduce the amount of granular powder remaining at the bottom of the silo without causing disadvantages such as increasing the slope of the silo portion and reducing the silo capacity. shall be.

[Structure of the invention]

The structure of the present invention is such that a sheet member having substantially the same shape as the bottom plate is arranged on the upper surface of a silo bottom plate formed in a generally funnel shape, and the sheet member has an outer circumferential portion of a central circular hole, a peripheral portion, and at least one intermediate annular portion. are each circumferentially and airtightly fixed to the silo bottom plate or silo side plate to form a plurality of annular bags by the sheet member and the bottom plate, and sequentially fill gas from the outer annular bag to the inner annular bag. In the bottom structure of the silo for powder and granular materials configured to
The annular portion is provided with a stepped portion and is lower than the second annular portion of the bottom plate forming the second annular bag from the inside, and the inner edge of the sheet member passes through the central discharge port of the bottom plate. The outer edge of the sheet member forming the innermost annular bag is hermetically secured near the upper portion of the stepped portion of the bottom plate. It is characterized by the presence of

〔Effect of the invention〕

As described above, when the innermost annular bag is filled with gas, most of the sheet member forms a surface inclined toward the discharge port, and the discharge port is formed only by the substantially vertical sheet member. Since there are no protruding parts, there is an advantage that the amount of powder remaining at the bottom of the silo can be significantly reduced compared to the conventional method.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. The bottom structure of the silo of the embodiment is shown in FIG. 1, but the components that are substantially the same as the conventional bottom structure shown in FIG. 2 are given the same reference numerals as in FIG. do.

The bottom plate 50 includes an outer bottom portion 52 and an outer bottom portion 52.
an inner bottom portion 56 connected via a vertical wall portion 54 to
There is an outlet 58 in the center of the inner bottom 56.
is provided. The sheet member 8 has substantially the same shape as the bottom plate 50, and has a circular hole corresponding to the discharge port 58 in the center. The sheet member 8 has an outer peripheral edge 60 airtightly fixed to a position higher than the mounting position of the bottom plate 6 on the side wall 2, and an inner peripheral edge 62 connected to the discharge port 58 of the bottom plate 6.
Further, an intermediate annular portion 64 is hermetically secured to the upper edge of the vertical wall portion 54 .

In the above configuration, the side wall 2 and the outer bottom portion 52
When the outer annular bag 70 formed by the sheet member 8 is filled with compressed air, the sheet member 8 moves as shown by dotted lines 8 and 3, and most of the powder and granules on it are removed. Move the object onto the inner part of the sheet member 8. Subsequently, the sheet member 8 and
When the inner annular bag body 72 formed by the vertical wall portion 54 and the inner bottom portion 56 is filled with compressed air,
The sheet member 8 moves as shown by dotted lines 8 and 4. At this time, almost the entirety of the sheet members 8, 4 is inclined downward in the direction of the discharge port 58, and at the discharge port 58, after the sheet member 8 covers the discharge port 58, the discharge port 58 of the bottom plate 6 Since the sheet members 8 and 4 are airtightly fixed to the lower surface around them and have no protruding parts, most of the powder and granules on the sheet members 8 and 4 are allowed to fall to the discharge port 58.

According to the results of an experiment conducted by the present inventor in which flour was placed in a 2.8 meter diameter silo, 100 to 120 kg of flour remained in the conventional bottom structure described above, but only 20 to 30 kg of flour remained in the silo according to the present invention. Only kilograms of flour remained.

Although the above embodiment is configured with two inner and outer annular bags, the present invention can also be effectively implemented in a bottom structure with three or more annular bags. Of course.

[Brief explanation of the drawing]

FIG. 1 is a central sectional view of a bottom structure according to an embodiment of the present invention, and FIG. 2 is a central sectional view of a conventional bottom structure. 2... Side wall, 4... Outlet, 6... Bottom plate, 8...
... Sheet member, 20 ... Outer annular bag, 24 ... Inner annular bag, 50 ... Bottom plate, 52 ... Outer bottom, 5
4... Vertical wall portion, 56... Inner bottom portion, 58... Outlet, 70... Outer annular bag body, 72... Inner annular bag body.

Claims (1)

[Claims] 1. On the top of the silo bottom plate, which is roughly shaped like a funnel,
A sheet member having substantially the same shape as the bottom plate is arranged, and the outer circumferential portion, the peripheral portion, and at least one intermediate annular portion of the central circular hole of the sheet member are each circumferentially and airtightly fixed to the silo bottom plate or the silo side plate. In the bottom structure of a silo for powder and granular materials, a plurality of annular bags are formed by the sheet member and the bottom plate, and gas is sequentially filled from the outer annular bag to the inner annular bag. The first annular zone portion of the bottom plate forming the innermost annular bag surrounding the central discharge port portion is lowered by providing a stepped portion with respect to the second annular zone portion of the bottom plate forming the second annular bag from the inside. the inner edge of the sheet member extends through the central outlet of the bottom plate to the lower surface of the bottom plate and is hermetically secured thereto, and the outer edge of the sheet member forming the innermost annular bag A bottom structure of a silo for powder and granular materials, wherein the part is airtightly fixed near the upper part of the stepped part of the bottom plate.