JPH04122820A - Method for improving accuracy for metering ice - Google Patents

Abstract

PURPOSE:To enable metering accuracy to be improved by metering amount of ice to transferred by a screw conveyer in a large-amount throwing region with a metering valve and by compensating of cold water. CONSTITUTION:Approximately up to 90 % of a target metering value and the remainder are divided and the former and the latter are named a large- amount throwing region. In the large-amount throwing region, ice carried by a screw conveyer 4 is metered by a metering value 5 and is thrown continuously. In the small-amount throwing region, cold water which is carried by a cold water pipe 8 is metered by a metering valve 9 and is thrown, a metered weight of cold water which is thrown instead of ice at the small-amount throwing regionis added to the metered weight of ice which is thrown in the large-amount throwing region, thus achieving a target metering value. Therefore, metering can be made accurately at the small-amount throwing region for improving accuracy of actual metering value and reducing error with the target metering value.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for improving the accuracy of ice measuring using an ice measuring device used in a concrete raw material mixing plant.

[Conventional technology] In a concrete raw material mixing plant, in addition to coarse aggregate, fine aggregate, cement, etc. as raw materials for concrete, ice is measured and released in the required amount, and these are mixed in a mixer to make concrete. It's Nishide.

As shown in FIG. 4, the ice weighing device for weighing ice has a screw conveyor 4 for conveying ice in a water storage 3 above an ice weighing device l equipped with a discharge gate 2 at the bottom that can be freely opened and closed. A metering valve 5 is provided at the cutout port of the screw conveyor 4, and by opening and closing the metering valve 5, the ice from the screw conveyor 4 is introduced into the ice measuring device l, or the ice is stopped being input. It's Nishide. 6 is a load cell of the ice weighing device 1.

When feeding ice from the screw conveyor 4 to the ice measuring device 1, the measuring valve 5 is used until the target measured value is reached.
Ice is fed into the ice measuring device 1 from the screw conveyor 4 while being weighed by the screw conveyor 4. Conventionally, ice from the screw conveyor 4 is fed into the ice measuring device 1 by the measuring valve 5 up to approximately 90% of the target weight value. A large amount of ice is continuously fed into the ice weighing device 1 by weighing, and thereafter, ice is weighed little by little while the measuring valve 5 is intermittently opened and closed as a small feeding region until the target weight is reached. Then, the ice cream is put into the ice weighing machine L.

[Problems to be Solved by the Invention] However, the ice used for mixing concrete raw materials is usually sliced ice that is sliced into thin pieces of ice or flake ice that is shaped like shaved ice. Ice flakes stick together during feeding and become difficult to rectify. Therefore, when weighing a large amount of ice cream in a short period of time, the conventional method described above, which attempts to measure ice cream intermittently in a small input range to reach the target weight value, is difficult to measure by measuring the actual weight value and the target weight value. There was a large error between the two, and it was not possible to measure with high accuracy.

Therefore, the present invention aims to improve the measurement accuracy so that a target measurement value is achieved when a large amount of ice cream is weighed in a short period of time.

[Means for Solving the Problems] In order to solve the above problems, the present invention makes it possible to inject cold water in addition to putting ice from a screw conveyor into an ice weighing device, so that the weighed weight close to the target weighed value can be In the large input area, the cold water is measured using a metering valve at the outlet of the screw conveyor, and then, in the small input area where the final measurement is performed, the cold water is measured, and the final metered amount is supplemented with the measured value of the cold water. In addition, in the above-mentioned large input area, the ice feeding speed of the screw conveyor is made variable, and the metering valve is opened and closed.
The ice may be measured by stepwise opening and closing of the metering valve at high speed of the screw conveyor, fully open at low speed of the screw conveyor, and intermittent opening and closing of the metering valve at low speed of the screw conveyor.

[Function] Since the final measurement amount that reaches the target measurement value is supplemented with the measured value of cold water, this is compared to the case where the final measurement is performed by intermittent opening and closing of the metering valve for flaky ice that is difficult to rectify during supply. ,
It is easy to approach the target measurement value, and measurement accuracy can be improved.

By varying the feed speed of the screw conveyor and measuring the ice in stages in the large input area, a large amount of ice can be measured in a shorter time.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an outline of an apparatus for carrying out the method of the present invention, in which an ice weighing device 1 is provided above an ice measuring device 1, which is provided with a discharge gate 2 at its lower part, which can be opened and closed by the telescopic operation of an opening/closing cylinder 7. Facing the screw conveyor 4 that conveys the ice from the water storage 3, a metering valve 5 is provided at the outlet of the screw conveyor 4, and the metering valve 5 is used to measure the ice conveyed by the screw conveyor 4 and put into the ice measuring device 1. 5, and at a position above the ice measuring device 5,
A cold water metering valve 9 is installed in the middle of the cold water pipe 8 facing the cold water pipe 8 so that the cold water can be measured and put into the ice measuring device I. 6 indicates a load cell.

When ice is weighed by putting ice into the ice weighing device 1, it is divided into, for example, up to about 90% of the target weighing value and up to the remaining target weighing value. In the large input area I, the screw conveyor 4 is operated and the metering valve 5 is opened so that the ice conveyed by the screw conveyor 4 is continuously metered by the metering valve 5, and then , In the small input area (2), the ice metering valve 5 is closed and cold water is input instead of ice cream, so that the final metered amount is supplemented with cold water. That is, in the small input area ■ where the measured value is close to the final target value, the cold water sent through the cold water pipe 8 is metered by the metering valve 9, and the measured weight of the ice cream added in the large input area I is Add the measured weight of cold water to be added instead of ice cream in the small injection area ■ to reach the target measured value. Since cold water is used in the small input area (3), the measurement is performed accurately and the accuracy of the actual measured value can be increased, and the error between it and the target measured value can be reduced.

The relationship between the measuring time and the weighed weight in the above measurement is as shown in Figure 2. Since the final amount of ice weighing with the ice weighing device 1 is supplemented by cold water measurement, the weighing accuracy can be improved and a large amount can be measured in a short time. Ice weighing can be done.

In the above-mentioned embodiment, the measuring valve 5 is fully opened in the large input area I, and the ice sent from the screw conveyor 4 is continuously input into the ice measuring device 1, but in the large input area I, It is also possible to perform ice weighing in stages.

Figure 3 shows an example of dividing large input area I into stages.
The screw conveyor 4 operates at high speed for a predetermined time from the start of ice measurement, and then switches to low speed operation, and the ice metering valve 5 is kept fully open until a predetermined time elapses after switching the screw conveyor 4 to low speed. After that, the metering valve 5 is opened and closed intermittently to intermittently introduce ice, and the portion where the screw conveyor 4 is operating at high speed and the metering valve 5 is fully open is defined as the first step S1. The portion where the screw conveyor 4 is operating at low speed and the metering valve 5 is fully open is defined as the second step S2, and the portion where the screw conveyor 4 is operating at low speed and the metering valve 5 is intermittently opened and closed is defined as the third step S3.

If the large input area I is divided into stages and weighed in this way, a large amount of ice can be weighed in a short time in the first step S1 and the second step S2, and the screw conveyor 4 is moved at a low speed in the third step S3. In addition, since the ice cream is cut out intermittently, the ice cream can be added little by little at a low speed to improve measurement accuracy. In the small injection area (3), cold water is used instead of ice cream, as in the case of the previous embodiment, and the cold water is measured to bring it closer to the final target value.

According to this embodiment, in the large input area I, variable feeding speed by the screw conveyor 4 and opening/closing of the ice metering valve 5 are combined, and in the small input area ■, cold water is used, so that the measurement in the large input area ■ is possible. Improving accuracy, and making it possible to supplement the final weighing amount using water in the small input range■, reducing errors between the target weighing value and the actual weighing value, improving weighing accuracy. can be achieved.

[Effects of the Invention] As described above, according to the method for improving ice measurement accuracy of the present invention, the actual measurement classification of ice used for mixing concrete raw materials until reaching a predetermined target measurement value can be made as simple as possible. It is divided into a large feeding area where ice is fed into the ice scale up to a weight value close to the target weight value, and a small feeding area where the remaining final weight is fed into the ice weighing device. By measuring with a valve and supplementing the final amount with cold water, the final amount can be measured quickly and accurately, and the difference (error) between the actual measured value and the target measured value can be reduced. It can be made smaller and the measurement accuracy can be improved. In addition, in the above-mentioned large input area, the first step is to increase the feeding speed by the screw conveyor and fully open the ice metering valve, and the second step is to reduce the feeding speed by the screw conveyor to fully open the ice metering valve. and a third step in which the feeding speed by the screw conveyor is set to a low speed and the ice metering valve is opened and closed intermittently, the first step, the second step,
By weighing in the order of the third step, and by measuring cold water in the small input area, the weighing weight increases even in the large input area. can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an apparatus for carrying out the method of the present invention;
Fig. 2 is a measurement procedure diagram showing one embodiment of the method of the present invention, Fig. 3 is a measurement procedure diagram showing another embodiment of the method of the invention, and Fig. 4 is a schematic diagram of a conventional ice weighing device. be. l...Ice measuring device, 2...Discharge gate, 3...
Ice storage, 4...Screw conveyor, 5...Measuring valve, 8...Cold water piping, 9...Cold water measuring valve, ■...Large input area, ■...Small input area.

Claims (2)

[Claims] (1) In order to discharge the ice used for mixing concrete raw materials from the ice weighing device at a predetermined target weighing value, the process of feeding the ice into the ice weighing device while weighing the ice until the weighing value reaches the target weighing value is set forth above. It is divided into a large feeding area where ice is fed up to a measurement value close to the measured value, and a small feeding area where the final amount of ice is fed.In the large feeding area, the ice fed by the screw conveyor is measured with a metering valve. Then, in the small input area, measure the cold water with the cold water metering valve,
A method for improving ice measuring accuracy characterized by supplementing the final measured amount with cold water. (2) a first step in which the ice feeding speed by the screw conveyor is set to a high speed in the large input area to fully open the metering valve; a second step in which the ice feeding speed is set to a low speed and the metering valve is fully opened; divided into a third step in which the ice feeding speed is set to a low speed and the metering valve is intermittently opened and closed;
A method for improving ice measuring accuracy according to claim 1, wherein the ice cream is weighed by operating the first step, second step, and third step in this order.