JPS61230031A - Method and device for continuous weight measuring - Google Patents

Abstract

PURPOSE:To measure precisely the weight of powder, etc., supplied continuously in the constant quantity by measuring and calculating a weight change per micro time of each feeder and subtracting the weight change amount of a final feeder from that of an intermediate feeder. CONSTITUTION:When a transported material in a hopper 2 reaches a certain amount, a stop signal is sent to a belt conveyer 1 so that the measurement load signal of the load cell 5 of the intermediate feeder 4 can be inputted to an arithmetic controller 10. Simultaneously the weight change amount per micro time is obtained from the measurement load signal at every micro time. The measurement load signal of the load cell 9 of the final feeder 8 is inputted to an arithmetic part 11 to obtain the weight per micro time from the measurement load signal by micro time. The weight change amounts per micro time from the arithmetic control part 10 and the arithmetic part 11 are inputted to a comparing part 12 to obtain the difference between them.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a continuous measuring method and apparatus for measuring the flow rate of continuously supplied powder, granules, liquid, etc.

[Conventional technology]

For example, in a bacha plant, a predetermined proportion of cement,
Fresh concrete is prepared in batches by mixing sand, gravel, water, etc.

However, if a large amount of ready-mixed concrete is required, it is necessary to have multiple large-sized mixing machines, and also hoppers,
Measuring instruments, etc., must also be from Daisho.

Therefore, a method of continuously mixing and supplying fresh concrete can be considered, but for this purpose, it is necessary to continuously supply fixed amounts of cement, sand, gravel, water, etc.

However, conventionally used weighing devices are equipped with two weighing hoppers (α) and (b) as shown in Fig. 6, and by switching the damper (C), the material in the hopper < b is There is a method of continuous cutting on a conveyor (by discharging from the other hopper (α) and weighing and discharging each one alternately), and a method of measuring the weight below the hopper as shown in Figure 7. There is a method of arranging a conveyor 0).

[Problem that the invention seeks to solve]

However, in the former method, the cutout amount (flow rate) becomes unstable when switching the metering hopper (α), and it is not possible to always ensure a constant flow rate.

In addition, the latter is unreliable because it tends to cause errors in weight measurements due to the impact of sand etc. being cut out.

As described above, the reality is that there is no suitable means for measuring the weight of continuously supplied powder, granular material, liquid, etc.

[Means for solving problems]

The present invention aims to solve the above problems.
An intermediate delivery machine with a hopper is connected to a final delivery machine with a hopper, and the final delivery machine is operated continuously at a predetermined delivery rate, and the intermediate delivery machine is operated intermittently so that the delivery volume is greater than that of the final delivery machine. to prevent the hopper of the final delivery machine from becoming empty, measure and calculate the weight change per minute unit time of each of the delivery machines, and subtract the weight change of the final delivery machine from the weight change of the intermediate delivery machine. By subtracting, a continuous weighing method was constructed.

Furthermore, a weight-measurable intermediate delivery machine that includes a material supply line, a hopper that receives the material supplied from the supply line, and a hopper that receives the material that is intermittently delivered from the intermediate delivery machine. Calculate the minute time-by-minute weight differences sent from the weight-measurable final sending machine equipped with a weight measurement unit and the weight measurement section of each sending machine to determine the amount of weight change, and then calculate the difference between the weight changes. A continuous weighing device was constructed with a calculation controller.

[For production]

A material to be delivered, such as cement, sand, gravel, water, etc., is fed into a hopper of an intermediate delivery machine through a material supply line, and when the hopper reaches a certain amount, the feeding line is stopped.

Next, the operation of the intermediate delivery machine is started, and a fixed amount of the material to be delivered is delivered to the hopper of the final delivery machine, the weight is measured at minute intervals, and the amount of change in weight per minute unit time is calculated by a calculator.

Further, the final delivery device continuously delivers a fixed amount at a delivery rate smaller than the delivery amount of the intermediate delivery device, the weight is measured at minute intervals, and the amount of change in weight per minute unit time is calculated by a calculator.

The weight change amount of the intermediate feeder is the amount fed into the final feeder, and the weight change amount of the final feeder is the difference between the fed material and the delivered material. By calculating the difference between them using a computer, the final output amount of the output unit per minute unit time can be determined.

〔Example〕

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

Figures 1 and 2 show a first embodiment of the present invention, in which a hopper (2) and a hopper (2) are provided below the drop opening of a belt conveyor (1) for conveying objects. An intermediate delivery machine (4) configured with a belt conveyor (3) is arranged so as to be able to measure the weight via a load cell (5), and below the drop opening of the belt conveyor (3) of the intermediate delivery machine (4), A final delivery device (8) consisting of a hopper (6) and a belt conveyor integrated with the hopper (6) is arranged so that its weight can be measured via a load cell (9).

The measured load signal of the load cell (5) of the intermediate feeder (4) is input to the calculation control unit αω, and the hopper (2
) When the delivered material reaches a certain amount, a stop signal is sent to the belt conveyor (1), and the amount of weight change per minute unit time is determined from the load signal measured every minute time.

Further, the measured load signal of the load cell (9) of the final sending machine (8) is inputted to the calculation unit αυ, and the weight change amount per minute unit time is calculated from the measured load signal every minute time. be.

Further, the minute weight change amount per unit time from the arithmetic control section αυ and the arithmetic section αD is inputted to the comparison section α2 to find the difference between them.

In the figure, α3a4)αS+U each heald conveyor (1) (
31 (7) motor, (161 is a continuous delivery control unit, (I
η indicates an arithmetic controller.

With the above configuration, when a certain amount of material to be fed into the hopper (2) by the belt conveyor (1) is reached, the calculation control unit A signal is sent to stop motor αj.

Next, when the belt conveyor (3) is driven by the motor a4, the material to be delivered in the hopper (2) is delivered in a fixed amount and is thrown into the hopper (6) of the final delivery &(81).

During this time, the total load of the intermediate feeder (4) is measured by the load cell (5) at minute intervals, and the measured load signal is sent to the calculation control section α1. When the amount of material to be delivered in the hopper (2) has decreased or has disappeared, the belt conveyor (3)
) is stopped, and the conveyed material is again thrown into the hopper (2) by the belt conveyor (1).

The above-mentioned weight change of the intermediate feeder (4) is shown in a graph as shown in the upper part of FIG.

When a certain amount of material has accumulated in the hopper (6) of the final delivery machine (8), the belt conveyor (7) is driven to continuously deliver the material with a smaller delivery amount than that of the intermediate delivery machine (4). When the final feeder (8) is fed out, the weight change of the final feeder (8) is detected by the load cell (9)K in the same manner as described above, and the change is detected by the calculation unit αB.
sent to. This weight change is shown in a graph as shown in the lower part of Figure 3.

After the intermediate sending machine (4) starts sending out, from time Ti to Ti+1
The weight change in minute unit time up to this point is wi + 1 - uli, and similarly the weight change of the final delivery machine (8) is Pi + t.
Since Pi, the continuous cutting amount of the final sending machine (8) is expressed by the following formula (1), assuming that the change in the continuous cutting amount of the final sending machine (8) is Wi+1-Wi.

Further, the speed V of the belt conveyor (7) that makes the continuous cutting amount of the final feeder (8) constant is expressed by the following equation (11).

(K is a proportional constant determined from the conveyor delivery amount) Based on the above, the delivery weight per minute unit time of the intermediate delivery machine (4),
By measuring the weight change per minute unit time of the final delivery machine (8), the amount of speed change of the belt conveyor (7) is determined so that the delivery amount of the final delivery machine (8) is constant, and the continuous delivery control unit By controlling by αη, accurate weight measurement can be carried out continuously.

FIG. 3 shows a second embodiment of the present invention, in which a belt conveyor (1) (3) is constructed in substantially the same manner as the first embodiment.
This is an example in which screw conveyor α8α[1] is used instead of (7). In FIG. 5, the same reference numerals as in FIG. 1 indicate the same parts.

In the case of this embodiment, as in the previous embodiment, it is possible to accurately measure the weight of the delivered product that is continuously delivered in a fixed amount.

FIG. 4 shows a third embodiment of the present invention, in which the configuration is substantially the same as that of the first embodiment, but the final feeder (8) is equipped with a motor c1.
This is an example in which a gate valve (2) which can be opened and closed by a gate valve 11 is provided and controlled by a continuous delivery control unit Qf9. Fourth
In the figure, the same reference numerals as in FIG. 1 indicate the same parts. - In the case of this embodiment, when the delivery speed of the belt conveyor (7) of the final delivery machine (8) is constant, the opening uQ of the gate valve (c) is expressed by the following formula (...).

By measuring the weight delivered per minute unit time of the intermediate delivery machine (4) and the weight change per minute unit time of the final delivery machine (8), the amount delivered from the final delivery machine (8) becomes constant. By determining and controlling the amount of change Q in the opening of the gate valve, accurate weight measurement can be carried out continuously.

FIG. 5 shows a fourth embodiment of the present invention, in which a belt conveyor (11 (31 (
Pump @Q4J@ and pulp■(5)(
This is an example in which liquid feeding lines 129) (to) 09 each having a hopper (21) (61) and a storage tank @ (to) are provided.

In the case of this embodiment as well, by measuring the feed weight per minute unit time of the intermediate feeder (41) and the weight change per minute unit time of the final feeder (8), the weight change from the final feeder (81) is measured. By determining and controlling the opening change amount Q of the valve (2B) so that the delivery amount remains constant, accurate weight measurement can be performed continuously even in the case of liquid.

It should be noted that the continuous measuring method and apparatus of the present invention are not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

〔Effect of the invention〕

As explained above, according to the continuous weighing method and device of the present invention, it is possible to accurately and easily measure the weight of powders, granules, liquids, etc. that are continuously and quantitatively supplied. be effective.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the first embodiment of the apparatus of the present invention, FIG. 2 is a diagram showing weight change patterns of the intermediate delivery machine and the final delivery machine in FIG. 1, and FIG. FIG. 4 is an explanatory diagram of the third embodiment of the apparatus of the present invention,
FIG. 5 is an explanatory diagram of a fourth embodiment of the apparatus of the present invention, FIG. 6 is a diagram showing an example of a conventional weighing device, and FIG. 7 is a diagram showing another example of the conventional weighing device. (1) (3) (7) is a belt conveyor, (21 (6)
1 is the hopper, (4) (41 is the intermediate feeder, +51 (9
) is the load cell, (81 (85 is the final delivery machine, αη is the arithmetic controller, (181 (19m is the screw conveyor, @
is the gate valve, @C301C+1) is the liquid supply line, (
2) ■ indicates a storage tank.

Claims (1)

[Scope of Claims] 1) An intermediate delivery machine with a hopper is connected to a final delivery machine with a hopper, and the final delivery machine is operated continuously at a predetermined delivery amount, and the intermediate delivery machine is connected to a final delivery machine with a hopper, and the intermediate delivery machine is connected to a final delivery machine with a hopper. The hopper of the final sending machine is operated intermittently so that the weight is larger than the amount of weight, so that the hopper of the final sending machine does not become empty, and the weight change per minute unit time of each sending machine is measured and calculated, and the final value is determined from the weight change of the intermediate sending machine. A continuous measurement method characterized by subtracting the amount of change in weight of the sending machine. 2) A weight-measurable intermediate delivery machine that includes a material supply line, a hopper that receives the material supplied from the supply line, and a hopper that receives the material that is intermittently delivered from the intermediate delivery machine. Calculate the minute time-by-minute weight differences sent from the weight-measurable final sending machine equipped with a weight measurement unit and the weight measurement section of each sending machine to determine the amount of weight change, and then calculate the difference between the weight changes. 1. A continuous weighing device characterized by comprising a calculation controller that performs