JPS6086424A - Constant flow rate feeding method using loss-in-weight type feeder - Google Patents

Abstract

PURPOSE:To improve the accuracy of feeding of a constant flow rate by using two loss-in-weight type feeders, and at the switching of discharging feeding prescribed starting materials to the feeder side in executing the discharging up to the switching. CONSTITUTION:Discharging is executed by using two loss-in-weight type feeders 1, 2 alternately, and at the switching of discharging the feeder 1 side in executing the discharging up to the switching fades out a flow rate Ft1 and the feeder 2 side starting the logging fades in a flow rate Ft2 to control respective flow rates so that (Ft1+Ft2) gets near an objective flow rate F0. Since the material is fed to the feeder 1 side in executing the discharging after the completion of fade-out, the flow rate is always controlled so as to get near the object flow rate F0 even in the feeding of the material when observed from the feeding side of the material, so that the accuracy of feeding of a constant flow rate can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a constant flow rate supply method using a loss-in weight type feeder.

The loss-in weight type feeder calculates the actual cut-out flow JilFt from the reduced weight per unit opening of the raw material storage amount, and calculates Ft
The operation of the feeder drive motor is controlled so that mFo approaches the target flow mFo. Conventionally, one loss-in-weight type feeder is used to feed each raw material, and when the raw material storage amount reaches the lower limit, the drive motor is operated at a constant rotation speed based on past operations to replenish the raw material. Afterwards, normal operation is resumed based on the weighed value, and the raw material is cut out without interruption even during raw material replenishment.

However, with such a constant flow rate supply method, cutting is not interrupted even during raw material replenishment, but since it is in an uncontrolled state during raw material replenishment, it cannot be expected that the target flow rate FO will be sufficiently close to the target flow rate during this time, and the accuracy of constant flow rate supply may be affected. The current situation is that it is decreasing.

An object of the present invention is to provide a constant flow rate supply method using a loss-in-weight type feeder that can bring the flow rate during raw material replenishment sufficiently close to the target flow kFo.

In the constant meteor supply method using a loss-in-weight feeder according to the present invention, the first feeder alone maintains the target flow rate F until the raw material storage amount on the first feeder side reaches the lower limit. When the raw material storage M on the first feeder side reaches the lower limit value, the flow rate of the first feeder is faded out and the flow rate of the second feeder is faded in. Time 1. If the occasional flow rate of the second feeder is Ftl * Ft2, then (Ft, +Ft
2) is the target flow rate F.

After the fade-out of the first feeder is completed, the raw material is supplied to the first feeder side, and the first
The second feeder is used to cut out the raw material when replenishing the raw material to the second feeder.

Hereinafter, specific embodiments of the present invention will be described based on FIGS. 1 to 8.

FIG. 1 shows the configuration of the mechanical parts of a loss-in-weight type feeder used for constant meteoric feeding of one raw material.

Q) (2) is the first. Second loss-in weight type feeder [hereinafter referred to as the first loss-in weight type feeder] (referred to as the second feeder)], (3) (
4) are respectively 1st. When replenishing raw materials to the second feeders (1) and (2), the first feeder [d] is closed. The second raw material replenishment valve (5) (6) is the first raw material replenishment valve. Second feeder (1) (
2]. Second load conversion device, (7) (
8) is the first. The first feeder that drives the second feeder (1) (2). This is the second drive motor.

First, when starting operation. Second feeder (1) (2)
Hopper (9) (II is filled with raw material. First, the first feeder (1) is operated based on the total λ value W1 of the first load converter (5), and the As in section A, the flow rate of the first feeder (1) [Fig. 2 (a)] approaches the target flow rate o, and the flow rate of the second feeder (2) [Fig. 2 (b)] approaches the flow rate ' In this ward A, the weighed value W11 and the weighed value W2 of the second load converter (6) on the second feeder (2) side are respectively the second
As shown in Figures (d) and (e), the weighed value Wl is approximately F per unit time. The weight value W2 remains constant at the upper limit value W2H and does not change.

Then, when it is detected that the raw material storage amount in the hopper (9) has reached the lower limit value WIL by performing individual cutting by the first feeder (1), as in section B, the first feeder (
The meteors at the second feeder (2) are controlled so that they gradually decrease and the meteors at the second feeder (2) gradually increase. Note that here, the first. If the occasional flow rates of the second feeders (1) and (2) are Ftl and Ft2, then the first. The fade-out and fade-in of the second feeders (1) and (2) are controlled so that they approach (Ft1+Ft2) = Fo, and as shown in Figure 2 (C), the general supply company has maintained that section B is the same as section A. To F. can be approached.

When the fade-out and fade-in are completed by executing section B in this way, the feeder @2 (2), like the first feeder (1) in section A, reaches the target flow rate F0 based on the weighed value W2. In section C, the second feeder (2) performs independent raw material cutting. In addition, the raw material supply to the first feeder (1) whose raw material storage amount has reached the lower limit value is performed. In section C after the fade-out is completed, the Ihojogo G is connected to the raw material replenishment valve (3).
1 and ends when the weighed value W1 reaches the upper limit value WIH.

FIG. 8 shows the principle of a control system that executes the control shown in FIGS. 2(a) and 2(b). Ql) (2) is the actual flow rate Ft1. The flow rate calculation unit that calculates Ft2 is a comparison unit that calculates a flow rate error by comparing the target flow rate Fo and the actual Ft, and 0< is a rotation speed determination means that is calculated by the comparison unit Q4. The number of rotations of the drive motor (7) required to bring the flow rate error close to zero is determined, and the DC voltage Ev1 is output at a level corresponding to the number of rotations. (
G) is a fade-out means that gradually approaches zero at a constant speed, and in section A, outputs the input DC voltage EVI as it is, and lower limit detection section Q
When Q detects W1=WIL, it is configured to start fading out. αη is the fade-out means (
Drive motor (7) according to the DC voltage EVI via II
This is a power variable control unit that executes power control to the Also on the second feeder (2) side, there is a comparison section (2) similar to the rotation speed determining means and the power variable control section Qη.

A rotation speed determining means (11, power variable control section - is installed), and a comparison section (to) is calculated by the g nose section (2) (F
Fade-in control of the drive motor (8) in section B is performed by comparing ll-F (1) with the flow rate Ftz.

In the above embodiment, the case of replenishing raw material to the feeder (1) of il was explained, but when the raw material storage amount of the second feeder (2) reaches the lower limit value W2L by executing section C,
Fade out the amount of cut from the second feeder (February), fade in the cut amount of the first feeder (1), and then switch to the second feeder (2) after completing the fade out of the second feeder (2). The specific control device required to alternately perform fade-out and fade-in in the first and second feeders (1) and (2) is as follows: Drive motor (7) with 8 diagram configuration
(8), manually inputs the weight value W2 to the flow rate calculation unit αυ, inputs the weight value W1 to the flow rate calculation unit (2), and controls the drive motor (8) with the power variable control unit (Iη). This can be easily realized by replacing the drive motor (7) with the power variable control section in the same manner.

Furthermore, in each of the above embodiments, the fade-out of one side was followed by the fade-in of the other p current;
The same effect can be obtained by configuring that the cut-out flow rate Ft2 of the feeder (2) @2 is faded in at a constant slope, and the cut-out flow In Ftl of the first feeder (1) is faded out following Ft2. can get.

As explained above, according to the constant fAL amount supply method of the present invention, two loss-in weight type feeders are prepared and cutting is performed alternately, and at the time of switching, the feeder that has been performing cutting until then is is 1+i+m
Ftl is faded out, and then cutting is started at 9. On the feeder side, flow m Ft2 is faded in (
Ft, 10Ft2) is the target flow rate F. After fade-out is completed, the raw material is supplied to the feeder side that had been performing cutting until then, so that from the perspective of the side where the raw material is supplied, even when the raw material is being replenished, the
. It is constantly controlled so that it approaches the same, and you can expect constant flow with high precision for long periods of time.

[Brief explanation of drawings]

The front side shows a specific example of the constant flow supply method of this research, Fig. 1 is a configuration diagram of the mechanical part, and Figs. 2 (a) to (e) show the main parts of Fig. 1 during supply execution. The waveform diagram and FIG. 8 are the basic configuration diagrams of the metropolitan equipment. (1) (2)...First. Loss-in weight type feeder of No. 2, (5) (6) --- 1st. Second load reversing device, (7) (8)...'1. 2nd drive motor, (9) 60"...hopper, a$m-...comparison section, α401...rotation speed determining means, (to)...due-out means, (Isu...lower limit detection part, θη0t...
Power variable control section, C21J... Subtraction section, Fo... Target flow company agent Yoshihiro Morimoto Figure 1 Figure 2

Claims (1)

[Claims] 1. Until the raw material storage amount on the first feeder side reaches the lower limit, the first feeder alone performs constant flow cutting so as to approach the target flow ji Fo~, and the raw material storage amount on the first feeder side When the lower limit is reached, the flow rate of the first feeder is faded out, and the Thh amount of the second feeder is faded in, so that the flow rate of the first feeder at this time is faded out. If the occasional flow rate of the second feeder is respectively)'tl+Ft2, then (Ft,
+ Ft,) is controlled so that it approaches the target flow fn Fo, and after the fade-out of the first feeder is completed, the first feeder
A constant flow supply method using a loss-in weight type feeder that replenishes raw materials to the feeder side.