JPS63300919A - Automatic quantitative supply metering device - Google Patents

Abstract

PURPOSE:To accurately perform short-time supply and also realize continuous quantitative supply which is stable and accurate for a long time by performing control which uses both instantaneous value control and integral value control when articles are supplied quantitatively by a conveyor. CONSTITUTION:Articles 2 with constant weight are supplied by a metering conveyor 5 automatically and quantitatively within a specific period. Here, the articles 2 thrown in a hopper 1 are conveyed by a conveyor 3 and supplied from a shooter 4 to a conveyor 5, and weight data on the articles 2 is generated by a metering part A. Then a control part B operates when an automatic operation mode is set by an automatic/manual switching part 6. Then a target supply quantity in a next period is corrected according to the ratio of the integral value of target supply quantities in a certain sample period and the integral value of an actual supply quantity. Further, conveyor speeds are adjusted according to the corrected target supply quantity and instantaneous control over the supply of articles 2 is performed so articles 2 can be supplied accurately and stably in both a long and a short period.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an automatic quantitative feeding and measuring device that automatically controls the amount of articles conveyed by a conveyor to be supplied at a constant weight.

(Prior Art) When producing various processed foods, etc., a certain amount of raw materials and semi-processed products may be conveyed to the next production process using a conveyor.

As an example of such a quantitative feeding apparatus using a conveyor, Japanese Patent Publication No. Sho 55-14368 describes one that performs instantaneous value control. This instantaneous value control is performed using the characteristics shown in FIG. In the figure, the horizontal axis represents time tn (see), and the vertical axis represents instantaneous transport amount W.
x (kg/5eC), and calculate the difference ΔWx between the instantaneous transport amount Ws=f (t) and the reference transport amount WS at each sampling time 1;, 12. ... is detected every time, and the variation amount ΔWx
The conveyor speed V (m/5ec) is controlled so that the That is, generally the instantaneous transport amount WX is Wx''(Ws+
ΔW, )−V·=lt), and focusing on the fact that Wx is a function of the conveyor speed V, quantitative supply control is performed.

Further, as an example of quantitative supply control, integrated value control as shown in FIG. 7 may be performed. This control is performed from time tl to t
The total transportation amount Wt in the area surrounded by diagonal lines up to 2 is expressed as Wt''(t''Wx −Vd t...
- Obtain as (2) and compare this with the standard transport amount between 1 and -1 surrounded by the rectangle t, -w, -w2-t2, and perform control so that the difference in area becomes zero. It is something.

(Problems to be Solved by the Invention) The conventional quantitative control device as described above has the following problems.

(1) Instantaneous value control device Since it performs control to approach the target value at each sampling time instant, it has the advantage of short response time, but errors tend to occur with respect to the target value, and the errors increase over long periods of driving. accuracy.

(2) Integrated value control device When driven for a long time, there are few errors and the accuracy is improved, but the responsiveness is poor and the accuracy is reduced when driven for a short time.

Therefore, the present invention provides an automatic quantitative supply metering device aimed at solving the problems of the prior art.

(Means for Solving the Problems) In the automatic fixed quantity supply weighing device of the present invention, which supplies articles of a fixed weight to an automatic fishing rod by a conveyor within a predetermined period, there is a means for setting a target supply amount, and a sampling time tn.
-1 and t. t of the next sampling period;
Means for correcting the target supply amount between n and tni1 according to the ratio, and means for controlling the instantaneous value of article supply by adjusting the conveyor speed with respect to the corrected target supply amount. It is characterized by:

(Function) The present invention is capable of supplying a fixed amount of articles by a conveyor, and calculates the target supply amount for the next sampling period based on the ratio of the cumulative value of the target supply amount for a certain sampling period and the cumulative value of the actual supply amount. Since the corrected target supply amount is corrected and instantaneous value control is performed on the corrected target supply amount, articles can be stably supplied with high precision in both short and long periods.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. Second
The figure is an external view showing a schematic configuration of an automatic quantitative supply metering device to which the present invention is applied. The device of the present invention has a weighing section A and a control section B, the details of which will be described later.The article 2 put into the hopper 1 is transferred by the conveyor 3, and the weight of the article supplied from the chute 4 to the weighing conveyor 5. The data is generated by the measuring section A. The weighed items are sent to the next processing step. The control unit B operates when the automatic operation mode is set by the automatic/manual switching unit 6, and controls the conveyor speed so that the amount of articles supplied is constant. A sensor 7 attached to the hopper senses when the articles falling from above reach a certain upper limit level in the hopper, and the falling amount control unit 8 stops the supply amount, and when the articles decrease and reach the moderate level, it is stopped again. Detects and starts supplying.

FIG. 3 is a characteristic diagram illustrating the present invention in detail. In the figure, Wxto is the initial target value W between time 0 → t1
, t, is time 1. The target value is between -12. Time t, →
Accumulated value of actual transportation volume (1+-■-■-tz) relative to cumulative value of standard transportation volume (1+-〇-■-tz) during t2
Find the ratio (■-■-■ part of the figure), and calculate the ratio of time 1. -1
3, the supply amount corresponding to ■−■−■ (■−■−■−■
) is subtracted from the reference transport amount t2----t3 to perform instantaneous value control by setting the target value Wlt2. That is, the present invention is characterized by the simultaneous use of instantaneous value control and integrated value control.

FIG. 1 is a block diagram showing a schematic configuration of the present invention. As shown in the figure, the weighing section A includes a power supply section a1 that is supplied with AC 100cm, an amplification section a2 that amplifies the weight of the article weighed by the load cell C, and an analog output from the amplification section a2 that converts it into a digital value. Analog-digital converter (A
/D converter a3), and a one-chip CPU a4 that outputs weight data from digital weighing values to the control unit.

Further, the control unit B may be configured to include an external manual means, such as a keyboard D.
Control CPU into which signals and weight data are input
bl, a display board b2. which outputs a signal to a display section E, the details of which will be described later. Speed detection section b connected to speed sensor section F
3. It is composed of a D/A conversion section that outputs a signal to the motor section G, a motor control section b4 consisting of a driver section, a data communication section b5, and a temperature detection section b6 connected to the temperature sensor section H. The temperature sensor section H is, for example, a thermistor, which is placed near the load cell C and the amplifier section a2, measures the temperature at certain fixed time intervals, and refers to a pre-stored correction value for the temperature from a memory table. Correct the weight measured by load cell C. The correction value for temperature is obtained by taking the measured value for temperature (zero point measured value) when goods are not being supplied or weighed, such as during breaks, at night, or on holidays.
The measured value for this temperature is stored as a correction value in a table in the memory in the control CPUb.

At this time, when the measured value differs for the same temperature within a certain time, if the difference is within the amount of change at the nth time, the memory of the correction value is updated. n and k are determined by the type of object to be measured and the measurement accuracy; for example, n = 3 times, k
= 2 grams.

FIG. 4 is a flowchart showing the processing procedure of the present invention. Next, this flowchart will be explained.

(1) Step P to check whether the mode is for weighing to obtain a correction value. ), if it is not in this mode, check whether the sampling time for weight detection has ended (step PI), and if the determination is No, then check whether the control time for the conveyor drive motor has ended (step P2). ). If the determination is NO, then check whether the timer for controlling the integrated value of the weight detected at each sampling time has finished operating (step P3), and if a timeout is confirmed, the integrated error Wd, for example, time 1. −
The amount of change with respect to the reference transportation amount during the period of 12 is calculated, and the target reference value W 5 t+ 1 for the next sampling period is set (step P4).

Next, if there is a change in the weighing data (step P), the weighing data is manually input (step P25), and a correction value corresponding to the current temperature measured by the temperature sensor section H/temperature detection section b6 is stored in memory. Based on this correction value, the weighing data manually entered in step P25 is corrected (
Step P28), Step P. Return to processing. If there is no change in the weighing data, when key-on is confirmed (step P6), key processing is executed in step P7.
), if the time designation key is on (step P8), the time is set (step P9), and the process below step pH is repeated.

(2) In the process of step P2, if a timeout of motor control is confirmed, then a motor control output timer is set (step P1o), and a check is made to see if the sampling time is output (step P1□). If the determination is NO, each conveyor drive motor 1 for conveyance and weighing
．． 2 (the drive motors of the pulleys at both ends on which the conveyor is stretched) is output (Step P1 □
). Next, confirm that the sampling time is not output (step P13), adjust the motor current of the conveyor to control the upper and lower limits of weight wu and wi (step P14), until the sampling time is output. The process below the step pH is repeated (step P1.).

(3) If the output of the sampling time is confirmed in the process of step P, then the process proceeds to the process below the step pH.

■Set the sampling time and motor output timer at T1 (step P +s).

■Calculate the weighing conveyor speed V (step P +y)
. This conveyor speed is determined by constants such as the diameter of the belt pulley and gear ratio given in advance, and the time T1 set by ■.
Calculate by.

(2) Calculate the transport amount Wt of articles during the sampling time (for example, between times t1 and t2 in FIG. 3) using the conveyor length between the pulleys, the conveyor speed V determined in (2), etc. (step P18).

- Calculate weighing/conveyance motor control data DH (step P19). This data D)I is the transportation amount w determined by ■
t% standard transportation amount, for example, 1, -1 in FIG. It is calculated from the amount of change with respect to the standard between 12 and 13, the target standard value between 12 and 13, etc.

(2) Calculate the reference value fluctuation rate Dw using the transportation amount Wt obtained in (2), for example, the target reference value between t2 and t5 (step P2°).

■The actual transport amount WtH per unit time is added to the Wt obtained in ■ by 3.
Calculate by multiplying by 600 (Step P21). (2) Calculate the actual scene cumulative transport amount WTo by integrating Wt obtained in (2) (Step P22).

(2) The total actual transport W T + at the specified time is calculated by integrating the Wt obtained in (2) over the specified time, for example, from tl to t2 in FIG. 3 (step P23).

■As above. , WtH,WT, , WT, are displayed on the display panel (step P24).

(4) Step P when the weighing conveyor is set to a mode in which weighing to obtain a correction value is performed automatically or manually when the weighing conveyor is empty and there are no articles on it. The determination is YES, and the weighing/conveying conveyor is stopped (step P27). The temperature sensor section H/temperature detection section b6 measures the current temperature R+ (step P2♂), and the weighing conveyor stops and weighs the weight in an empty state, that is, the weight W at seven points (step P29). Weight W' at the previous zero point at temperature R1
1 and the weight WI at the zero point weighed in step P29 this time (Step P30). If they are not equal, the number of times they are not equal is the nth time and the weight W1 is W', -, and W'. , +, and check whether it is within the range of step P3. ), if it is determined as YES,
Instead of the weight jEW'+, the current weight W1 at the zero point is stored as a new correction value (step P32). Note that, for example, it is preset that n=3 times and k1=2 grams. Step P. If the determination is YES in step P31 and NO in step P31, and after step P3□ is executed, it is confirmed that a certain period of time has elapsed (step P33), and the process returns to step P0.

In this way, in the present invention, the weighing data acquisition interval is set as a sampling time, and within that time, the speed calculation of the weighing conveyor, the actual transported amount of goods, the motor control data, the reference value fluctuation rate, the actual accumulated transported amount, Calculate the amount of traffic in a time-specified actual scene and display the results.

Further, the motor is controlled by setting a control timer for the motor for driving the weighing conveyor, and at the same time, when the upper and lower limits of the weight of the article transportation amount are exceeded, the speed of the weighing conveyor is controlled so that the weight falls within the specified upper and lower limits. At this time, the weight and speed calculations for the instantaneous value and the integrated value are also executed in parallel, and when the upper and lower weight limits are reached, the control is returned to the original state.

FIG. 5 is a schematic configuration diagram showing an example for checking the accuracy of ffi amount data according to the present invention. In the figure,
Articles are placed from hopper X into weighing hopper Y, and the weight is detected. The articles weighed in the weighing hopper are then weighed by the automatic metering device of the present invention. The weight data at this time is compared with the data obtained from the weighing hopper.

As a result, it was confirmed that the accuracy was within ±1%.

Further, the fixed supply amount can be changed using the numeric keypad even while the device is in operation.

(Effects of the Invention) As explained above, the present invention performs control using both instantaneous value control and integrated value control when supplying a fixed amount of articles by a conveyor, so that supply can be performed in a short time with high precision. At the same time, it is possible to supply a stable quantity over a long period of time.
Furthermore, continuous quantitative supply with high precision can be realized. moreover,
The effect is that the fixed amount of supply can be easily changed.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a schematic configuration of the present invention, Fig. 2 is an external view, Fig. 3 is a characteristic diagram, Fig. 4 is a flowchart, Fig. 5 is an explanatory diagram, and Figs. 6 and 7 are characteristics. It is a diagram. A...Measuring section, B...Control section, C...Load cell, D...Keyboard, E...Display section, F...Speed sensor section, G...Weighing/conveyance motor section . Patent applicant: Ishida Kouki Seisakusho Co., Ltd.
Person Patent attorney Minoru Tsuji 1 Konbu B Teitomerine Hosho 9 (Method) August 27, 1986 2. Title of invention Automatic constant supply metering device 3. Relationship to the amendment person case Patent applicant Address: 44 Goin Sanno-cho, Sakyo Ward, Kyoto City, Kyoto Prefecture Name: Ishida Koki Seisakusho Co., Ltd. Representative: Ishi 1) Takashi - 4, Agent: August 5, 1988 (Delivery date: 62.8) .25) 6. Drawings subject to correction 7, Contents of correction 1 62.8. ?

Claims (1)

[Claims] In an automatic quantitative supply measuring device that automatically supplies a constant quantity of articles of a fixed weight by a conveyor within a predetermined period, there is a means for setting a target supply amount, and an integrated value of the actual article supply amount between sampling times t_n_-__1 and t_n. means of calculating,
Means for calculating the ratio between the integrated value of the target supply amount and the integrated value of the actual supplied amount within the time, t_n of the next sampling period
and t_n_+_1 according to the ratio, and means for controlling the instantaneous value of article supply by adjusting the conveyor speed with respect to the revised target supply amount. Features: Automatic quantitative supply metering device.