JPS61274225A - Automatic balance of granular substances - Google Patents

Abstract

PURPOSE:To effect rapid and accurate measurements regardless of classifications of the supplied granular substances, by detecting valve opening time of an operating valve when a feeder is driven under the specified condition set according to the maximum flow rate of various classifications of granular substances, and resetting the specified condition according to thus detected operation time of the valve. CONSTITUTION:When a feeder A is driven under the specified condition set respectively according to the maximum flow rate of granular substance by a setting means B, establishment of each specified condition is identified by an identifying means C and each operating valve (a) of the feeder A operates in such a way that supply speed of the granular substances from the feeder A is reduced every time when the specified condition is established, and on the other hand, a detecting means D detects operating time of each operating valve (a). A revision means E resets the specified condition according to the detected value of the operating time. Consequently, the operating time of each operating valve (a) is optimized in accordance with an actual flow rate of the granular substances.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an automatic granular material weighing machine capable of weighing accurately and quickly.

BACKGROUND OF THE INVENTION Weighing machines are already known in which granules are fed to a weighing section at a gradually decreasing feed rate, and the supply of granules is stopped when a predetermined weight is reached, so that the weighing can be carried out accurately and quickly. ing. However, for example, in the case of granular materials, the flow speed changes depending on the smoothness of the particle surface and the particle size, so if you want accurate weighing, the weighing time will increase, while on the other hand, shortening the weighing time is However, there was a problem in that it was easy to cause errors in measurement.

Problems to be Solved by the Invention It is an object of the present invention to provide an automatic granular material weighing machine that can quickly and automatically weigh various granular materials having different flow speeds without causing measurement errors.

Means for Solving the Problems The present invention, as shown in FIG. a setting means B for setting each predetermined condition according to the maximum flow velocity of the granular material; a discriminating means C for determining whether each of the predetermined conditions is satisfied; A detecting means for detecting the opening time of each of the on-off valves when a substance is supplied, and an updating means for resetting the predetermined condition according to the detected value of the opening time of each on-off valve. Consists of composition.

When the supply device A is operated under the predetermined conditions respectively set according to the maximum flow speed of the granular material by the action setting means B, the determination means C determines whether each predetermined condition is met, and each opening/closing of the supply device A is performed. The valve a is opened and closed so that the supply speed of the particulate matter from the device A is reduced every time the predetermined condition is satisfied, and the detection means detects the opening time of each on-off valve a. The updating means E resets the predetermined conditions according to the detected value of the valve opening time. As a result, the opening time of each on-off valve a is optimized according to the actual flow velocity of the particulate matter.

Embodiment FIG. 2 shows the main part configuration of automatic weighing of granular materials according to an embodiment of the present invention. The large supply and medium supply on-off valves 5.6 are driven to open and close by air cylinders 3.4, respectively, and the small supply vibration gutter 8 is vibrated and supplied by the operation of the vibration device 7. The rice is dropped into the measuring tank 9, and each on-off valve opens and closes to form a feeding device that feeds the rice at a gradually decreasing feeding rate. Roughly, the rice in the measuring tank 9 is opened and closed by an air cylinder 10 and an on-off valve 11 and a hopper 1.
A synthetic resin bag 1 is placed on a bag holding table 13 via a plastic bag 1 and has an open end gripped by a sealer/chucking body 14.
5, the open end is sealed with a sealer/chucking body 14. Then, while the synthetic resin bag 15 filled with a predetermined amount of rice is transferred to a predetermined site by appropriate means, a new synthetic resin bag 15 is set and the above-mentioned weighing is repeated.

In order to accurately and quickly fill a predetermined amount of rice into the synthetic resin bag 15, the meter is equipped with a control device 16 (FIG. 3) that operates according to a control program to be described later, and the weighing tank 9 is connected via a load cell 17. The weighing tank 9 is supported by a frame 18, and the load cell 17 detects the total weight of the weighing tank 9 and the rice put therein. As shown in FIG. 3, the control device 16 includes an input/output circuit 2 of one microcomputer.
0, the central processing unit (CP
IJ) 22 performs information processing, and via an input/output circuit 20, an operation panel 23 with a display and various drive circuits 24 to 2
7, and the control panel 23 with display operates according to this control output, while the air cylinder driving solenoid interposed between the compressed air source (not shown) and each of the air cylinders 3, 4, and 10 described above 28-30 and the vibrating device 7 are operated to control the rice packing.

An outline of the operation of the weighing machine constructed as described above will be explained with reference to FIG. 4. Prior to operating the weighing machine, the operator sets a constant value to provide a predetermined condition via the operation panel 23, which is a setting means. In other words, the fixed amount WO as the target weight value is set to 5 kg, and the allowable range of supply amount is set to 5 ka.
~5 kg+3! J, and input the detected value of the dead weight of the weighing tank 9 displayed on the operation panel 23 with a display to adjust the zero point for measuring the amount input into the weighing tank 9.
Further, the large supply time To, the pre-quantification setting value We, and the head correction value Wo are initialized. Initial settings for providing this predetermined condition are performed assuming that the flow velocity is the highest among the granular materials to be measured, and the parameters TO and Ws that define the large supply and medium supply times To and TI are set to, for example, 0. The correction value Wo is preliminarily set to .6 seconds and 500 (+).The correction value Wo is set to, for example, 10 g in order to compensate for the weight of the particulate matter flowing down in the air at the time of a small supply stop.

After the initial settings are completed, rice is supplied from the supply tank 2 to the measuring tank 9 at a supply rate that gradually decreases in three stages based on a determination by a determining means that determines whether each of the predetermined conditions is satisfied. That is, until the preset large supply time To elapses, the air cylinder 3 is actuated to open the large supply on/off valve 5, and the imaging device 7 is operated to vibrate the small supply vibrating gutter 8, and then the small supply is supplied. The medium supply on-off valve 6 is opened by the operation of the air cylinder 4 for T1 hours until the amount reaches the value WO-WB, and the small supply is executed by photographing the vibration gutter 8 for small supply by the operation of the medium supply and vibration device 7. However, only a small supply is performed by vibrating the small supply vibrating gutter 8 by operating the vibrating device 7 for 12 hours until the value WO-Wo is reached at the earliest. Thereafter, the rice falling through the air is supplied into the measuring tank 9, and the supplied amount becomes a value close to a constant fiWo.

Furthermore, the supply time TI is the opening time of the on-off valves 5 and 6 detected by the detection means during the measurement.

Each supply time To is determined as described later according to the detected value of T2.
- the metrological control parameter To that defines T2;

The settings of We and Wo are changed by the updating means, and the second and subsequent measurements are performed at a feeding time of TO to T2 according to the actual flow speed of the rice being fed in this way, without causing measurement errors.
We are trying to shorten the required weighing time.

FIGS. 5(a) to 5(C) show flowcharts of the metering control execution program. First, after the above-mentioned constant settings and initial settings are performed (steps S1 and S2), the synthetic resin bag 1
When a total ffifm start signal is generated (step 83), which is output from an appropriate means (not shown) every time the set of 5 is completed, C
The PU 22 drives the solenoid 28 and the vibration device 7 to simultaneously perform large supply and small supply (step 84). When the set large supply time TO has elapsed, the solenoid 28 is demagnetized to stop only the large supply, and the solenoid 29 is activated to start the medium supply, medium supply and small supply are performed, and at the same time the medium supply execution time is stopped. Start measuring T1 (
Steps 85-88).

Next, it is determined based on the output of the load cell 17, etc. whether the supplied amount ff1iW of rice supplied into the measuring tank 9 as described above is a difference of 4.5 kq or more between the constant JiWo and the pre-metering set value WB. When the value W reaches 4.5 kG, the solenoid 29 is demagnetized to stop only the medium supply and continue only the small supply (steps 89 and 810). Then, at the same time as the medium supply stops, the measurement of time T1 is finished, and the measurement of the small supply independent execution time T2 is started, and the masking process is performed (
Steps 811, 512). This mask processing is to cut off the input of the measured value W as a control input to prevent measurement errors, since the measured value of heavy ff1W tends to become temporarily excessive due to shock vibration when medium supply is stopped. for example,
Runs for 1.3 seconds. Then, in step 813, the supply ff1ffi value W1 at the time of canceling the masking process is measured.
), then the supply amount ff1W is constant iWo and the head correction IW
It is determined whether the difference between the weight W and o is WO-Wo = 5k (+-10g or more), and when the supplied weight W reaches the difference, the small supply is stopped and the 12-hour measurement is ended (steps 814 to 814).
816).

Next, the rice grains that were falling through the air at the time of the small supply stop are dropped into the measuring tank 9, and the amount of rice ωWF supplied into the measuring tank 9 is measured. kg + 30 or not, and if it is within the allowable range, the solenoid 30 is activated to dispense the rice in the measuring tank 9 and fill it into the synthetic resin bag 15 (step 81
7-819).

Next, in order to shorten the required measurement time, each setting value set in step S2 is reset. First, medium supply■ If the measured value for 1 hour is 1.9 seconds or more, set large supply time T
While adding 0.1 seconds to O to shorten the required weighing time,
If it is 1.4 seconds or less, subtract 0.1 seconds and reset the large supply time TO to prevent measurement errors, and if the medium supply time T1 exceeds 1.4 seconds and is less than 1.9 seconds. If so, the current set value is maintained (steps 820-523).

And if the measured value for 12 hours exceeds 3.3 seconds,
In order to match the flow velocity of the target rice, which is smaller than the flow velocity assumed at the time of initial setting, or to correct the set value that has been changed thereafter, the value Ws is decreased to shorten the short supply time T2 (step 824. 825). In addition, if 12 hours is equal to 1.3 seconds, that is, if the measured value W1 of supply 1 at the end of mask processing is greater than or equal to the value Wo-Wo, the pre-quantification setting value is increased by 10 (+ The supply time T2 is made longer (step 826~
828). If 12 hours exceeds 1.3 seconds and is less than 2.3 seconds (the mask process is performed for 1°3 seconds, 12 hours is always 1.3 seconds or more), the process moves to step 829 and the WB is executed. We −<Wo −Wo −Wl ) + (
(Wo -Wo -W 1)/(T2-1.3)) to shorten the small supply time T2. On the other hand, if 12 hours is more than 2.3 seconds and less than 3.3 seconds, change the setting. Not performed.

Next, the following process is executed to reset the head correction value Wo. First, only when 12 hours exceeds 1.3 seconds, the number n of effective measurements of the actual supply ffi WF is counted, and the effective measurement value WF is added to obtain the integrated weight I W T (steps 830-832).

Then, until the count value n reaches the predetermined number of times 5, (
Step 833), measure the weight of the weighing tank 9, and correct the zero point based on this measurement value Steps 839 and 840)
, wait for the next weighing. On the other hand, when the weighing is repeated as described above and the count value n reaches 5, the cumulative weight W is divided by 5, the average supply ff1Wv' is 19, and this value W
Constant ff1W from T'.

is subtracted to obtain the correction value Wo', and the added value of this value Wo' and the current value of the head correction value Wo is used as the head correction value W for the next measurement.
The settings are changed to be used as o (steps 834 to 8
36). Next, the count value n and the accumulated weight WT are cleared in step S37゜538), and the step S3 described above is performed.
Execute steps 9 onwards.

If it is determined in step 818 that the actual supply ff1WF is not within the allowable range, the process moves to step S41, and T1
If the time exceeds 1.4 seconds, set the large supply time TO to 0.
After resetting to shorten the time by 1 second (step 841~
843), if the T1 time exceeds 1 second and is less than 1.4 seconds (step S41.542), the process directly proceeds to step 844. Then, 12 hours exceeds 1.3 seconds and condition T
2≧((WF-Wo)(T2-1.3)/(Wo
-Wo -Wl )) If +1.3 holds true, that is, if it is determined that 12 hours will be a value of 1.3 seconds or more after head correction, then the error between the actual supply ffi WF and the quantitative set value WO After changing the setting of the correction value Wo to the current value of the head correction value Wo and the current value of the head correction value Wo (steps 844 to 546), on the other hand, if 12 hours after the head correction is less than 1.3 seconds, For example, after changing the setting to the addition value Wa + (WF - wo ) of the above error and the pre-quantification setting value We (steps 845 and 847), stop the measurement, investigate the cause of the accountant's error, and make the necessary adjustments. After the remaining amount dispensing operation (steps 848 and 849), the system waits for the next weighing.

If the actual supply m WF is outside the allowable range, the above-mentioned metering stop process is performed at T1. , is always executed even in cases other than the T2 time condition. In other words, when 11 hours is less than 1 second,
The fixed quantity setting value WO is divided by the supply weight per 0°1 second due to large supply, for example 300g, and the value is subtracted from the actual supply IWF to obtain the correction coefficient value A, and the current value of large supply time TO is 0.1A. After changing to shorten seconds (step S41゜850.551), on the other hand, 11 hours is 1.4
If 12 hours or more and 12 hours is 1.3 seconds or less, the pre-quantification setting value W8 is changed to the value W B + (WF - wo ) (steps 841, 842, 844, 852), and the process proceeds to step 348 above. . Furthermore, even when zero point correction is not performed, measurement is stopped to investigate the cause (steps 840 and 845).

Effects of the Invention As described above, according to the present invention, when the supply device is operated under predetermined conditions set according to the maximum flow velocity of various granular materials to be measured, the opening and closing valves of the supply device can be opened and closed. Since the time is detected and the predetermined conditions are reset according to the detected valve opening time, even if the type of granular material to be supplied is different, once the measurement is performed, the actual flow of the granular material can be determined. The predetermined conditions can be set so that the required weighing time is minimized depending on the speed and no measurement error occurs, and granular materials can be automatically weighed quickly and accurately.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing means for solving the problem, Fig. 2 is a schematic front view showing the main part configuration of an automatic granular material weighing machine according to an embodiment of the present invention, and Fig. 3 is a block diagram showing a means for solving the problem. , a block circuit diagram showing the control device of the weighing machine of the above embodiment together with peripheral elements, FIG. 4 is a graph explaining the operation of the weighing machine of the above embodiment, and FIG. 5 is a block circuit diagram showing the operation of the weighing machine of the above embodiment. 2 is a flowchart of a metering control program. 2... Supply tank, 3.4.10... Air cylinder, 5.6... Opening/closing valve, 7... Photographing device, 8... Small supply vibration gutter, 9... Metering Tank, 11... Opening/closing valve, 15... Synthetic resin bag, 16... Control device.

Claims (3)

[Claims] (1) a supply device that supplies particulate matter at a supply rate that gradually decreases by opening and closing each on-off valve each time a predetermined condition is satisfied; a setting means that sets each of the predetermined conditions according to the maximum flow velocity of the particulate material; a determining means for determining whether each of the predetermined conditions is satisfied; a detecting means for detecting the opening time of each of the on-off valves when granules are supplied under the predetermined conditions set by the setting means; and updating means for resetting the predetermined conditions according to the detected value of the opening time of each of the on-off valves. (2) The automatic granular material weighing machine according to claim 1, wherein the predetermined condition includes that the on-off valve is open for a set valve opening time. (3) The automatic granular material weighing machine according to claim 1 or 2, wherein the predetermined condition includes that a predetermined weight of granular material is supplied from the supply device.