JPH0579927B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is applicable to cereal flour, cereal grains, seasonings, detergents, drugs, dyes, sand, gravel, cement, ceramic powder,
The present invention relates to a device for automatically supplying a designated amount of powder or granules (hereinafter referred to as powder or granules) such as plastic powder or plastic granules, and an automatic measuring device using this device. More specifically, the present invention relates to an apparatus for feeding and measuring powder and granular materials in a batch system using a belt feeder.

[Prior art] Conventionally, this type of powder supply device using a belt feeder regulates the layer thickness of the powder on the belt and adjusts the supply amount of the powder according to this layer thickness. A powder weighing device is provided, in which a layer thickness damper is arranged on the belt, and a cut damper is arranged near the downstream end of the belt to block the powder from falling from the downstream end of the belt to the weighing hopper. It has been proposed (for example, Utility Model Application No. 62-152228).

In the particle measuring device disclosed in Japanese Utility Model Application Publication No. 62-152228, a small amount damper with a notch is further arranged near the downstream end of the belt and above the cut damper, and this small amount damper increases the We try to measure powder and granular materials with precision.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional device, when changing the degree of fine supply of powder or granular material by the small quantity damper, it is necessary to change the position of the notch plate that constitutes the small quantity damper when the small quantity damper is not activated. It was necessary to shift the size of the notch or replace another notch plate with a different size of notch. For this reason, once the small volume damper is set in the device and operated, the amount of fine feed before the fall of powder and granules is interrupted becomes constant, and there was a problem that the fine feed amount could not be changed unless the belt feeder was stopped. . As a result, there remains room for further improvement in order to supply powder and granules with higher accuracy to the target measurement value.

An object of the present invention is to provide a powder and granular material feeding device that can continuously change the small feed amount during the operation of a belt feeder, and can supply a precisely specified amount of powder and granular material in batches in a short period of time. Our goal is to provide the following.

Another object of the present invention is to provide a measuring device for automatically weighing powder or granular material using the above-mentioned feeding device.

[Means for Solving the Problems] In order to achieve the above object, the powder and granular material feeding device of the present invention includes a supply hopper for storing powder and granular material, and a supply device disposed below the supply hopper to supply the powder and granular material from the supply hopper. a belt feeder for conveying powder and granular material to a measuring container; a distance adjusting means for moving the belt feeder upward or downward to adjust the distance between the belt of the belt feeder and the lower end of the supply hopper; and driving the belt feeder. and a controller for controlling the interval adjusting means and the feeder driving means.

Further, in the powder/granular material measuring device of the present invention, the measuring container is mounted on an electronic scale, and the controller controls the feeder driving means and the interval adjusting means based on the weighed value of the electronic scale. It is.

[Function] The controller controls the feeder drive means and the interval adjustment means, so that the lower end of the supply hopper continuously regulates the layer thickness of the powder on the belt, and the lower end of the supply hopper and the belt It is possible to perform continuous feeding from coarse feeding when the intervals are wide to fine feeding when the intervals are narrow.

[Example] Next, an example of the present invention will be described in detail based on the drawings.

As shown in FIGS. 1 to 9, the supply hopper 10 that stores the powder or granular material A is provided with an arch breaker 11 that prevents crosslinking of the powder or granular material A, and below the supply hopper 10, the supply hopper 10 A belt feeder 12 is arranged to convey the powdered material A to the weighing container 25. The belt feeder 12 is a supply hopper 10
This is a small-sized belt conveyor that has a belt width and belt length that are wider than the spread area of the granular material A discharged from the belt conveyor. Arch breaker 11 is motor 11a
The measuring container 25 is mounted on an electronic scale 26. Lower end 10 of supply hopper 10
a is formed into a cylindrical shape in this example, and this lower end 1
A movable cylinder 14 having a notch 13 in the conveyance direction of the belt feeder 12 is fitted into Oa so as to be movable upward or downward. A stopper 15 is provided at the lower end 10a to determine the lowest position of the movable cylinder 14.
(Fig. 4 and Fig. 7).

The belt feeder 12 includes a belt 16, a driving roll 17, driven rolls 18 and 19, and a stationary plate 20.
The drive roll 17 is driven by a feeder drive device 21. Belt feeder 12
is the distance adjusting device 2 together with the feeder driving device 21.
2 to adjust the distance D between the belt 16 and the lower end 10a of the supply hopper 10 by moving diagonally upward in the direction opposite to the conveyance direction (direction B) or diagonally downward in the same direction as the conveyance direction (direction C). I'm starting to get it.

The movable cylinder 14 that fits into the lower end 10a of the supply hopper 10 moves from the stopper 15 when the belt 16 separates from the lower end 10a as shown in FIGS.
It moves downward due to its own weight until it stops at (Fig. 4 and Fig. 7), and when the belt 16 of the belt feeder 12 rises, it comes into contact with the belt 16 and moves upward as shown in Fig. 8 and Fig. 9. Constructed to be movable. In order to guide the vertical movement of the movable cylinder 14, a protrusion 10b is provided on the outer periphery of the lower end portion 10a.

As shown in FIG. 1, the electronic scale 26 has a built-in load cell 27 and an AD converter 28.
The output of converter 28 is connected to a control input of controller 23. The controller 23 includes a setting device 29 for setting a target amount to be poured into the container 25.
The control output of the controller 23 is the arch breaker 1
1 motor 11a, feeder drive device 21, and interval adjustment device 22, respectively.

Next, the operation of the device having such a configuration will be explained based on the characteristic diagram shown in FIG.

First, the target value G to be measured is set using the setting device 29 of the controller 23. Next, the controller 23 activates the arch breaker 11 to prevent the powder and granules in the supply hopper 10 from bridging, while setting the target value G.
Based on this, the interval adjustment device 22 is controlled to move the belt feeder 12 diagonally downward in the same direction as the conveyance direction (direction C in FIG. 1). The movable cylinder 14 descends from the lower end 10a of the supply hopper 10 due to its own weight and stops at a stopper 15. When the distance D between the belt 16 and the movable cylinder 14 is set based on the target position G,
The powder A is discharged onto the belt 16 until it reaches a specific angle of repose.

Next, the feeder drive device 21 is operated to move the drive roll 1 of the belt feeder 12 based on the target position G.
Set the rotational speed of No. 7, that is, the conveyance speed of the powder or granular material. As a result, the powder or granule A has a trapezoidal cross section consisting of a spread in the width direction and an interval D according to the angle of repose of the powder or granule A.
is quantitatively supplied to the measuring container 25 according to the conveyance speed of the belt feeder 12.

When the weighing value of the electronic scale 26 reaches the switching value _S1 , which is 80% of the target value G, the controller 23 controls the interval adjustment device 22 to move the belt feeder 12 diagonally upward in the direction opposite to the conveyance direction (as shown in FIG. 1). B direction) and raised to a position where the belt 16 contacts the movable cylinder 14 as shown in FIG. As a result, only the entire cross section of the notch 13 of the movable cylinder 14 is opened, and the powder material A is supplied onto the belt 16 only from this notch 13. After this small supply state,
When the weighing value of the electronic scale 26 reaches the switching value _S2 , which is 95% of the target value G, the controller 23 further pulls up the belt feeder 12 using the interval adjustment device 22, and as shown in FIGS. At the same time, the feeder drive device 21 is controlled to reduce the rotational speed of the drive roll 17 to bring about a small amount supply state. When the weighing value of the electronic scale 26 reaches 99% of the target value G, the belt feeder 12 passes through the state shown in FIG. It is pressed against the lower end portion 10a of 10. In this state, all the discharge ports of the supply hopper 10 are closed,
The supply of granular material A is cut off.

As the belt feeder 12 approaches the target position G, the distance of the belt 16 to the supply port of the hopper 10 becomes shorter, and the powder A can be quickly dropped into the container 25, thereby shortening the measuring time.

Note that the control characteristics of the controller shown in FIG. 10 are merely examples, and the present invention is not limited thereto.

Furthermore, although the lower end of the supply hopper and the movable tube are cylindrical in shape, they are not limited to cylindrical shapes and may be rectangular tubes.

[Effects of the Invention] As described above, according to the present invention, the belt feeder is disposed below the powder supply hopper, and the distance between the belt of the belt feeder and the lower end of the supply hopper is adjusted. It is possible to easily switch continuously from supplying a large amount of granules to supplying a small amount of granules, and it is possible to accurately supply a set weight of granules in a short time without increasing the size of the device.

Further, by adjusting the conveyance speed of the belt feeder and the distance between the belt and the lower end of the supply hopper based on the weighing value of the electronic scale for weighing the weighing container, automatic weighing can be performed with high precision.

Particularly, by fitting a vertically movable movable cylinder having a notch to the lower end of the supply hopper, it is possible to supply and measure powder and granules with even higher accuracy.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a measuring device using a powder supply device according to an embodiment of the present invention. FIG. 2 is a view taken along the arrow in FIG. FIG. 3 is a plan view of FIG. 1. FIG. 4 is an enlarged sectional view of the main part of the lower end of the supply hopper showing the small amount supply state. FIG. 5 is a side view of the lower end of the supply hopper and the belt feeder showing the small amount supply state. FIG. 6 is a front view of FIG. 5. FIG. 7 is an enlarged cross-sectional view of the main part of the lower end of the supply hopper showing the extremely small amount supply state. FIG. 8 is a side view of the lower end of the supply hopper and the belt feeder showing the supply cutoff state. FIG. 9 is a front view of FIG. 8. FIG. 10 is a control characteristic diagram of the controller. A... Powder, 10... Supply hopper, 10a...
... Lower end of supply hopper, 12 ... Belt feeder, 13 ... Notch, 14 ... Movable cylinder, 15 ...
... Stopper, 16 ... Belt, 21 ... Feeder drive device (feeder drive means), 22 ... Interval adjustment device (interval adjustment means), 23 ... Controller,
25...Measuring container, 26...Electronic scale.

Claims (1)

[Scope of Claims] 1. A supply hopper for storing powder and granules; a belt feeder arranged below the supply hopper and transporting the powder and granules supplied from the supply hopper to a measuring container; a distance adjusting means that moves to adjust the distance between the belt of the belt feeder and the lower end of the supply hopper; a feeder driving means that drives the belt feeder; and a controller that controls the distance adjusting means and the feeder driving means. A feeding device for powder and granular materials. 2. A movable cylinder having a notch facing the conveying direction of the belt feeder is fitted into the lower end of the supply hopper formed in a cylindrical shape, and a stopper for determining the lowest position of the movable cylinder is provided on the supply hopper, The movable cylinder is configured to move downward under its own weight until it stops at the stopper when the belt leaves the lower end, and to move upward by coming into contact with the belt when the belt of the belt feeder rises. The powder supply device according to claim 1. 3. Claim 1, wherein the interval adjusting means is configured to move the belt feeder diagonally upward in the direction opposite to the conveyance direction thereof or diagonally downward in the same direction as the conveyance direction.
A feeding device for the powder or granular material described above. 4. The weighing container according to claim 1 is mounted on an electronic scale, and the controller according to claim 1 controls the feeder driving means and interval adjustment means according to claim 1 based on the weighing value of the electronic scale. Weighing device. 5. The powder and granular material weighing device according to claim 4, wherein the controller controls the feeder drive means to reduce the conveyance speed of the belt feeder in accordance with the weight value of the electronic scale approaching the target value.