JPS5824513Y2 - Transient pulse absorption circuit - Google Patents

Description

[Detailed description of the device] This device absorbs transient pulses that are erroneous measurement pulses in the input circuit of the electronic weighing device, which are used for measuring electricity, gas, water, etc., for example. The present invention relates to a transient pulse absorption circuit.

Generally, when measuring the amount of electric power, for example, a circuit configuration as shown in FIG. 1 is used.

FIG. 1 is an electrical wiring diagram showing a conventional power metering circuit.

- In the figure, the input signal source 1 applies voltage and current proportional to the power used to the watt-hour meter 2.

The electromagnetic section 3 of the wattmeter 2 rotates a rotating disk (not shown) at a speed proportional to the electric power, and at the same time rotates a circle having a cutout in proportion to the rotational speed of the rotating disk (not shown). Rotate plate 4.

An anti-coupling oscillation circuit 5 is provided near the disc 4 having the notch, which is electromagnetically coupled around the disc 4 having the notch.

The receiver 6 converts AC input from an AC auxiliary power source applied to terminals 7a and 7b into DC power by a DC power supply circuit 8 to excite coils 9a, 9b, and 9c of a step motor (not shown).

The receiver 60 input terminals 10a, 10b, 10c are connected to the anti-coupling oscillation circuit 5 of the watt-hour meter 2, and the anti-coupling oscillation circuit 5
"Oscillates" as the disc with the notch rotates 40 times, "
"Stop" is repeated and smoothed by the action of the smoothing capacitor built into each anti-coupling oscillation circuit, so the input terminals 10a, 10b, 10c are
A pulse voltage shown in 10c is applied, and the coils 9a, 9b, 9c of the step motor (not shown) of the receiver 8 are sequentially excited to rotate the step motor (not shown).
A meter (not shown) in the receiver 6 displays an indication proportional to the amount measured by the watt-hour meter 2.

Note that narrow noise pulses existing before and after each pulse voltage are generated in the following manner.

10a, 10b, and 10c in FIG. 2 indicate that the anti-coupling oscillation circuit 5 changes from "oscillation" to "oscillation" as the disc with the notch rotates 40 times.
The figure shows the voltage waveforms that appear at the input terminals 10a, 10b, and 10c when there is a transition from "stop" or "stop" to "oscillation."

Also, if the power usage is very low, the disc 4 with the sparks rotates at a very low speed or is at a standstill.

In this case, the anti-coupling oscillation circuit 5 just changes from "oscillation" to "stop".
, or when transitioning from "stop" to "oscillation", a phenomenon occurs in which the narrow transient pulse shown in FIG. 2 continues to oscillate even though the disc 4 having the notch is not rotating.

If the receiver 6 is a step motor (not shown), the noise pulse due to this phenomenon will not satisfy the response speed of the step motor (not shown) or the excitation conditions, and the noise pulse will not satisfy the step motor (not shown). does not rotate and will not cause incorrect weighing.

When measuring using a counter consisting of an electronic circuit with a fast response speed, such as an electronic circuit, for the meter receiver 6,
All of the above-mentioned phenomena that generate narrow-width noise cause weighing errors.

In particular, if the transmission continues when the disc 4 having the notch is stopped, there is a drawback that the receiver 6 exhibits a significant overmetering.

This idea was made in view of these drawbacks.

This idea will be explained below with reference to the drawings. FIG. 3 is an electrical wiring diagram showing an embodiment of the transient pulse absorbing circuit according to this invention.

In the figure, parts corresponding to those in FIG. 1 are given corresponding symbols.

In the figure, receiver 60 input terminals 10a, 10b.

Input signals having waveforms shown at 10a, 10b, and 10c in FIG. 2 are applied to 10c.

Also, an input terminal 10a. 10b and 10c are AND gate 1
1a, 11b.

11c and the input terminals of NOR gates 12a, 12b, and 12c.

That is, the input terminals 10a and 10b are connected to the AND gate 11a and the NOR gate N2a, the input terminals 10b and 10c are connected to the AND gate 11b and the NOR gate 12b, and the input terminals 10c and 10a are connected to the AND gate 11c and the NOR gate 12b, respectively. Each is connected to the Noah gate 12c.

Antoge-N1a, 11b. The output terminals of 11c are R, S
Flip 70 knob 13a.

The output terminals of the NOR gates 12a, 12b, 12c are connected to the reset terminals R of the R, S flip-flops 13a, 13b, 13c.

The output terminals Q of the R, S flip-flops 13a, 13b, 13c are the output terminals 14a, 14b, 14c of the receiver 6.
It is connected to the.

Next, this operation will be explained with reference to FIG.

1 applied to input terminals 10a, 10b, 10c
0a.

Input signals with waveforms shown in 10b and 10c are input to AND gates 11a, 11b, 11c and NOR gates 12a, 12.
b, 12c, Antoge N1a, 11b, 1
The output waveforms of 1c are as shown in 11a, 11b, and 11c in FIG. 2, and the output waveforms of 12a, 12b, and 12c are as shown in 12a, 12b, and 12c in FIG.

The R, S flip-flops 13a, 13b, 13c use the output signals of the AND gates lla, 1lb, 11c, that is, the signals 11a, 11b, 11c in FIG.

12c, ie, 12a and 12b in FIG.

It operates using the signal shown in 12c as a reset signal.

And the output terminal Q, that is, the output terminal 14a of the receiver 6
, 14b, 14c and 14a, 14b in FIG.

This produces the output shown at 14c.

That is, each R, S flip-flop 13a, 1
3b and 13c indicate that when the set signals 11a, 11b, and 11c in FIG. 2 are changing, the reset signals 12a, 12b, and 12c in FIG. When the reset signals shown at 12a, 12b, and 12c in the figure change (・), the reset signals shown at 11a, 11
It operates when the set signals shown in b and 11c do not change.

Therefore, R, S flip-flops 13a, 13b, 1
3c is set by the change in the set signal shown in 11a, 11b, 11c in FIG. 2, and then 12a, 12b in FIG.
, 12c, and the output waveform thereof, that is, the output terminal 14a.

The output waveforms appearing at 14b and 14c are 14a in FIG.
, 14b, and 14c, which are converted into signals containing no transient pulses.

Furthermore, even when the input signals of the receiver 60 input terminals 10a, 10b, 10c are stopped while continuing to emit transient pulses, the R, S flip-flops 13a, 13b
, 13c, only one of the set manual input and the reset input changes, so the output terminals 14a,
It is clear that the continuous transient pulse described above does not appear in 14b, 14c.

As described above, the transient pulse absorbing circuit according to the present invention not only can absorb transient pulses contained in an input signal with a simple circuit configuration, but also allows the transient pulse absorbing circuit according to the present invention to It is also possible to connect a circuit with a fast response speed to the latter stage, and for example, when used in a meter for measuring electric energy, etc., it is possible to produce a meter that is stable and inexpensive without erroneous measurements. It has various effects.

[Brief explanation of drawings]

FIG. 1 is an electrical wiring diagram showing a conventional power metering circuit. FIG. 2 is a signal waveform diagram of a conventional power metering circuit and a transient pulse absorbing circuit according to this invention. FIG. 3 is an electrical wiring diagram showing an embodiment of the transient pulse absorbing circuit according to this invention. In the figures, corresponding parts in each figure are given corresponding symbols, and 11a, 11b, 11c are 1st. Second
．． The third AND gate, 12a*12b-12c is the first
．． Second. Third Noah Gate, 13a. 13b and 13c are the first. Second. This is the 30th R, S7 flip-flop.

Claims (1)

[Scope of utility model registration request] The first . Second. 3rd and gate and 1st
．． Second. the third Noah gate, and the first. Second. Third
The output signal of the AND gate of the first . Second. The output signal of the third NOR gate is applied to the reset input terminal of the first. Second. A transient pulse absorption circuit characterized by comprising a 30th R, S flip-flop.