JPS6013129B2 - Hopper scale for constant weight dispensing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a Rossi-Soweit type hopper scale that calculates the amount of discharged material from the remaining amount of the material to be fed and supplies the material at a fixed rate.

Conventionally, in a loss-in-weight type hopper scale, the discharge is stopped when the remaining amount reaches Wo - W, which is obtained by subtracting the weight W of one discharge, based on the weight Wo of the remaining amount of the supplied material immediately before the start of discharge. It was something that worked.

Therefore, when replenishing supplies, it was necessary to stop discharging the supplies from the start of replenishment until the completion of replenishment.
Therefore, it was not possible to continuously supply a fixed amount using a loss-weight type hopper scale, and the work efficiency was poor. Therefore, the present invention solves the above-mentioned drawbacks and provides a hopper scale that can continuously supply materials. An embodiment of the present invention will be described below based on the drawings.

Figure 1 shows a block diagram of a loss-in-weight type hopper scale that controls the discharge amount per unit time to be a constant amount.
The load cell 3 outputs a weighing signal G corresponding to the weight value of the fed object 2. 4 is a rotary feeder provided at the bottom of the weighing hopper 1, and a rotation speed controller 5
The weighing hopper 1 is driven by a motor 6 controlled by the weighing hopper 1, and discharges the material 2 in the weighing hopper 1.

Reference numerals 7 and 8 are mitt switches for detecting that the remaining amount of the material 2 in the weighing hopper 1 has reached a lower limit and an upper limit, respectively.

A and A in FIG. 2A indicate output signal values of the load cell 3 corresponding to the lower and upper limits of the object to be supplied 2, respectively. Therefore, when the limit switch 7 detects that the material to be fed 2 in the weighing hopper 1 has reached the lower limit level, it determines that it is necessary to replenish the material to be weighed, and the other limit switch 8 The weighing hopper 1 is replenished with the material to be fed during the period until the upper limit level of the material is detected [FIG. 2 a, c]. Reference numeral 9 denotes a weight loss speed detecting unit, which detects the feed material 2 from the load cell 3 output signal (period 2 in FIG. A signal Ev corresponding to the rate of decrease in , that is, the discharge rate V from the weighing hopper 1 is output.

10' A supply amount setting section sets the supply amount per unit time and outputs a signal Evo corresponding to the set amount.

11 is a comparator, and the output signal Ev of the weight loss speed detection circuit 9 is
and the supply amount setting part quantity Q output signal Evo are input, and the content V of the output signal Evo of the reduction speed detection part 9 is determined by the supply quantity setting part quantity Q output signal Evo.
Contents V of output signal Evo.

The rotational speed control section outputs the signal Ec so as to match the rotational speed of the rotary feeder mother. 12 is a hold circuit, which is the limit switch? When detects the lower limit of the material to be supplied 2, the hold signal date is input and the output signal Ec of the comparator immediately before replenishment of the material to be supplied is output.
It stores and outputs.

Pack 3 is controlled by the hold signal at the switching section.
In period 2 of FIG. 2a, the comparator l output signal is
Two output signals are alternatively selected and input to the rotational speed control section 5. Therefore, even during replenishment of the supplied material 2 [period bar in Figure 2 a], the supplied material 2 from the rotary feeder turtle is
This does not mean that the emissions will stop. FIG. 2b shows the cumulative amount T of the feed material 2 discharged from the rotary feeder turtle,
In the evening of the replenishment period, the discharge amount state immediately before replenishment of the to-be-supplied material is maintained until the replenishment is completed, and the to-be-supplied material 2 is continuously discharged. Immediately after the replenishment of the to-be-supplied material in FIG. The hold circuit blade 2 is configured to store the output signal of the comparator 11, and the hold circuit blade 2 stores the output signal of the weight loss speed detection section 9 as shown in FIG. 3, and switches the input signal of the comparator 11. The same machine can be used even if the output signal of the weight loss speed detection section g and the output signal of the hold circuit 12 are selectively input through the section 13. can be easily obtained from the input signal or output signal of the rotational speed control section 5 that controls the rotational speed of the tally feeder 4.As described above, the constant weight dispensing hopper of the present invention.

According to the scale, when replenishing the weighing hopper, a hold circuit is installed that stores and outputs a signal corresponding to the discharge amount immediately before the start of replenishment, and the discharge amount of the weighing hopper is supplied from the start of replenishment to the completion of replenishment. Since the discharge amount is maintained at the state immediately before the start of replenishment of the material, it is possible to continuously supply a fixed amount without stopping even when replenishing the material to be supplied, resulting in extremely high work efficiency.

[Brief explanation of drawings]

Figure 2 is a block diagram of a hopper scale that is an embodiment of the present invention, Figure 2 a? b is a main part waveform diagram for explaining FIG. 1, and FIG. 3 is a block diagram of another embodiment. 1...- Weighing hopper, 2...Rotary feeder as well 3...Load cell 9...Reduction rate detection unit 2...
...Hold circuit. Figure 2 Figure 2? figure

Claims (1)

[Claims] 1. Control the feeding machine for discharging the material so that the discharge amount per unit time obtained from the change in the weight value of the material in the weighing hopper matches the preset discharge amount per unit time. In the hopper scale for constant weight dispensing,
When replenishing the weighing hopper with the material to be supplied, a hold circuit is provided which stores a signal corresponding to the discharge amount per unit time obtained from a change in the weight value of the material immediately before the start of replenishment, and outputs the stored content. . A hopper scale for constant weight dispensing, characterized in that the feeder is configured to maintain the discharge amount state immediately before the start of replenishment of the to-be-supplied material from the start of replenishment until the completion of replenishment.