JPS62173935A - Signal processor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a process input/output device, a signal processing device such as a telemeter device (remote measuring device), and particularly to a lightning protection structure thereof.

(Prior Art) Conventionally, there has been a technology in this field as shown in FIG. The configuration will be explained below.

FIG. 2 is a schematic configuration diagram showing an example of the configuration of a telemeter device, which is a conventional signal processing device.

This telemeter device is a device for indicating or recording the value of arbitrary immersion at a remote point, and it is a device for indicating or recording the value of arbitrary immersion at a remote point.
The sensor 1 is connected to the device body 3 by a pair of transmission lines 2. The device main body 3 includes a grounded immersion body 4, and a terminal block 5 having an input terminal 5-0.5-1 and a signal processing circuit 6 are housed in the housing 4. The input terminals 5-0.5 to 5-1 are connected to the transmission line 2, and are used to input an external signal transmitted from the sensor l via the transmission line 2 and input it to the signal processing circuit 6. The signal processing circuit 6 is a circuit that inputs external signals and performs various electrical processing.

In this type of device, each input terminal 5-0.
Is there a lightning arrester such as a ballista between 5-1 and flute body 4? -0
, 7-1 are connected.

The lightning arrester 7-0.7-1 has a characteristic that its resistance value decreases rapidly when a high voltage is applied. Therefore, when a high voltage is induced on the transmission line 2 by lightning, the induced current flows to the ground via the lightning arrester 7-0.7-1. This eliminates the influence of lightning on the signal processing circuit 6 and protects the telemeter device from lightning.

(Problems to be Solved by the Invention) However, in the device having the above configuration, when the number of sensors l is increased and a large number of input terminals 5-0.5-1 are provided, it is necessary to install a lightning arrester for each input terminal. -0,7-1,... to take lightning protection measures by connecting lightning arrester? The number of -0, 7-1, . . . increases. And a lightning arrester? Since lightning protection measures are taken only with -0 and 7-1, a large-capacity device that can handle high-voltage guided lightning is required, which poses the problem of increasing the size and cost of the entire device.

The present invention provides a signal processing device that solves the problem of the prior art in that lightning protection measures make the entire device larger and more expensive.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a plurality of input terminals connected to a plurality of transmission lines for transmitting external signals;
A signal processing device comprising a signal processing circuit that processes the plurality of external signals input from the input terminal,
A grounded conductive member is disposed close to the input terminal. Furthermore, a multiplexer circuit for signal selection is connected between the plurality of input terminals and the signal processing circuit, and a lightning arrester is connected between the multiplexer circuit and the signal processing circuit.

(Function) According to the present invention, since the signal processing device is configured as described above, the conductive member generates an air discharge between the input terminal and the high-voltage induced lightning, and the induced lightning flows out to the ground. Work like you do. The multiplexer circuit selects and outputs a specific signal from among a plurality of external signals inputted to a plurality of input terminals, so it functions to reduce the number of lightning arresters connected to its output side. The lightning arrester also functions to drain low-voltage induced lightning to the ground. This allows for a reduction in the number of lightning arresters and a reduction in their capacity. Therefore, the above-mentioned problem can be eliminated.

(Embodiment) FIG. 1 is a schematic configuration diagram of a telemeter device, which is one of the signal processing devices according to an embodiment of the present invention.

This telemeter device has a plurality of external signal output sensors 11-0-113 on the outside, and each of the sensors 11-0 to
11-3 are connected to the device main body 13 by transmission lines 12-0 to 12-4, respectively. Here, transmission line 12-4
is commonly connected to each sensor 11-θ to 11-3 and functions as a common line.

The device main body 13 includes a grounded flute body 14 made of metal or the like,
A printed circuit board 15 for mounting a circuit is housed within the flute body 14. A terminal block 16 is mounted on the printed circuit board 15. The terminal block 16 has a plurality of input terminals 16-
O~16-4, and each input terminal 1G-0~IB-
4 are connected to transmission lines 12-0 to 12-4, respectively.

In the vicinity of the terminal block mounting point on the printed circuit board 15, there are conductive wiring patterns 17-θ to 17-4 connected to each input terminal 16-0 to 16-4, and each input terminal 16-
A conductive member, for example, a ground pattern 18, is provided adjacent to 〇 to 16-4, respectively. Each wiring pattern 1
7-0 to 17-4 are connected to the multiplexer circuit IS, and the ground pattern 18 is connected to the flute body 14 and grounded.

The multiplexer circuit 18 has wiring patterns 17-0 to 17-1.
This circuit selects a specific signal from a plurality of external signals from sensors 11-0 to 11-3 that are input via sensor 7-4. A signal processing circuit 21 is connected to this multiplexer circuit 19 via a plurality of signal lines 20-θ to 20-4. The signal processing circuit 21 connects the signal line 20-0
Or, based on the manually input signal DO or Di from the multiplexer circuit 19 inputted via 20-1, various electrical processes are performed on the input signals DO and Di;
It outputs control signals To and TI and sends them to signal lines 20-2.
This circuit supplies the signal to the multiplexer circuit 18 via 20-3. Note that the signal line 20-4 functions as a common line.

Resistors 22-0 to 22-3 for overcurrent suppression are connected in series to each signal line 20-0 to 20-3, respectively, and
A lightning arrester 23-θ such as a varistor is provided on the signal processing circuit side of each resistor 22-θ to 22-3 and on the signal line 20-4.
~23-4 are connected. Each lightning arrester 23-0 to 23
-4 is connected to the residue 14 and grounded.

FIG. 3 is a main circuit diagram showing an example of the circuit configuration of the multiplexer circuit 19 in FIG. 1. This multiplexer circuit 1
Reference numeral 8 is composed of a diode matrix circuit, and a plurality of diodes 30-0 to 30-2 are connected between the signal line 20-0.20-2 and the wiring pattern 17-0. Line 20-0.22-3 and wiring pattern 17
-1, between the signal line 20-1, 20-2 and the wiring pattern 17-2, and between the signal line 20-1, 20-3 and the wiring pattern 17-3. are connected to each other. The signal line 20-4 and the wiring pattern 17-4, which are common lines, are connected to each other and grounded.

Figure 4 shows wiring patterns 17-0 to 17- in Figure 1.
2... and a partially enlarged view of the grounding pattern 18.

Wiring patterns 17-0 to 17-2... are formed on the printed circuit board 15, and one end 17a-0 to 17a-2...
is connected to each input terminal 16-0 to 16-2 of the terminal block 16, and the other end is connected to the multiplexer circuit 18. Furthermore, one end 17a-0 to 1 of the wiring pattern 17-θ to 17-2... in the printed circuit board 15J:
In the vicinity of 7a-2..., a Jl pattern 18 is formed with an interval G between them. Here, if the interval G is made smaller, air discharge becomes more likely to occur. For example, set the interval G to 0
．． The discharge voltage when the voltage is 5 mso is approximately 2.7 KV. Furthermore, once the discharge starts, the resistance value at the interval G decreases significantly.

Next, the operation of the signal processing device configured as described above will be explained.

(1) General operation of the signal processing device In FIG. When input to -θ to 16-4, the external signals are divided into groups by a multiplexer circuit 19 controlled by a signal processing circuit 21 and provided to the signal processing circuit 21. Thereby, the signal processing circuit 21 performs predetermined electrical processing on the input signal.

The operation of the multiplexer circuit 19 in FIG. 3 is as follows.

Control signals TO, TI on signal lines 20-2 and 20-3 output from the signal processing circuit 21 to the multiplexer circuit 19
Among them, one control signal TO is set to H level, which is a higher potential than the common signal line 20-4 potential (=OV), and the other control signal 〒1 is set to L level, which is the same potential as signal line 20-4. In this case, the potential of the input signal DO on the signal line 20-O output from the multiplexer circuit 19 to the signal processing circuit 21 is not affected by whether the sensors 11-1 to 11-3 are on or off. It is affected only by whether the sensor 11-0 is turned on or off. In other words, when the sensor 11-0 is off, the input signal DO goes to H level due to the diode 30-0.
Diode 3 through 0.30-2 and sensor 11-0
Since the level between 0-0 and 30-1 is low, the input signal D
O becomes L level. Signal line 20-1. h input signal D
The same applies to sensor 11-2, and if the sensor 11-2 is off, it is set to H level, and if it is on, it is set to L level.

Similarly, when one control signal TO is set to L level and the other control signal T1 is set to H level, input signal DO
is affected by the on/off of the sensor 11-1, and the human input signal DI is affected by the on/off of the sensor 11-3.
If 1-1.11-3 is off, the input signal DO is set to H level, and if it is on, it is set to L level.

In this way, multiple external signals are sent to the multiplexer circuit 1.
9 to be selected and given to the signal processing circuit 21, the lightning protection "Jjt23-0~23-4 is connected to the signal line 20-θ~
It is sufficient to provide only the external signals 20-4, and the number can be reduced compared to the conventional case where only the external signals are provided.

For example, when the number of external signals is mXn, and the multiplexer circuit 18 is configured with m rows x n rows, the number of lightning arresters is (m
+n+1), and this makes it possible to take lightning protection measures against mXn external signals.

(2) Lightning protection operation of the signal processing device In Fig. 3, when a lightning strike or the like occurs on the transmission lines 12-0 to 12-4, the induced current due to the lightning is transferred to the input terminals 16-0 to
16-4, diode 3 in multiplexer circuit 18
0-θ to 30-2... and resistance 22-0 to 22-3
... to the lightning arresters 23-θ to 23-3. Therefore, the diodes 30-0 to 30-2... and the resistors 22-θ to 22-3 are required to have performance commensurate with the lightning potential. Here, the resistance 22-θ ~ 22-3
suppresses the induced current of lightning, and the diode 30-θ ~ 30-2
It works to limit the current flowing to... In addition, the induced current varies depending on how lightning is induced.
It may flow in the forward direction or in the reverse direction with respect to 0-2.

Therefore, up to a certain zero potential, lightning protection W 23-0 to 23-3
Lightning protection processing is performed by the wiring pattern 17- on the printed circuit board 15 against induced lightning with higher potential.
Lightning protection is performed by air discharge between θ~17-4 and the ground pattern 18. Below, these lightning protection treatments will be explained in the fourth section.
This will be explained in detail with reference to FIGS. Note that FIG. 5 is a characteristic diagram of the zero potential vS, and FIG. 6 is a principal circuit diagram for explaining the operation of FIG. 3.

In FIG. 6, when a positive zero potential vS occurs at the input terminal 18-0, the induced current flows through the diode 30-0.
2.30-1 → resistor 22-0 → lightning arrester 23-o → earth,
It flows along the route ■. Furthermore, when a negative zero potential -VS occurs at the input terminal 16-0, the induced current flows from the ground to the lightning arrester 23-2 to the resistor 22-2 to the diode 30-0.30-
2. It flows along the route ■.

Here, the zero potential VS is increased in the order of g sec as shown in FIG. In the case of route ■, lightning arrester 23
-0 passing voltage is vl, the forward voltage of the diode 30-1 is v2, and the breakdown voltage of the diode 30-1 is VS, then the voltage applied to the resistor 22-0 is VS-Vl-V2- It becomes VS. The voltage at which the zero potential VS is (approximately 2700V
), the induced current flows in the direction of path ■.

However, when the voltage exceeds 2700V, as shown in FIG. 4, the wiring pattern 17- to which the input terminal 16-O is connected
An air discharge occurs between 0 and the ground pattern 18, and the resistance value between both patterns 17-0-18 decreases. Therefore,
The induced current passes between both patterns 17-o and 18 and flows to the ground, so it no longer flows in the direction of path (2). This causes diodes 30-2, 30-1, resistors 22-0.
and lightning arrester 23-o are protected from lightning.

In this way, for a low zero potential VS, the lightning arrester 23-θ
~23-0, in order to protect the circuits after wiring patterns 17-0 to 17-4 by air discharge between wiring patterns 17-0 to 17-4 and ground pattern 18 against high zero potential vs. , diode 3 of multiplexer circuit 18
0-0 to 30-2... and the resistors 22-o to 22-3 may be designed to withstand only the low zero potential vS. Therefore, the diodes 30-0 to 3o-2・
..., the capacity of the resistors 22-0 to 22-3 can be reduced, and the entire device can be made smaller and lower in price.

The present invention is not limited to the illustrated embodiment, and various modifications are possible. For example, the wiring patterns 17-0 to 17-4 may be replaced with lead wires, and air discharge may be caused directly between the input terminals 16-0 to 16-4 and the ground pattern 18. Furthermore, although the conductive member is configured by the ground pattern 18, it is also possible to configure this by a conductive plate or the like. Further, the circuit configuration of the multiplexer circuit 19 can also be modified to other configurations.

(Effects of the Invention) As described above in detail, according to the present invention, the number of external signals manually inputted is reduced by the multiplexer circuit, so the number of lightning arresters installed can be reduced. Moreover, since the conductive member is provided close to the input terminal, lightning protection is performed by the lightning arrester for low zero potentials and by the conductive member for high zero potentials. Therefore,
It becomes possible to reduce the capacity of the constituent elements of the multiplexer circuit and the lightning arrester, and as a result, the effect of reducing the size and cost of the entire device can be expected.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a signal processing device showing an embodiment of the present invention;
Figure 2 is a schematic configuration diagram of a conventional signal processing device, Figure 3 is a main circuit diagram showing an example of the configuration of the multiplexer circuit in Figure 1, and Figure 4 shows the wiring pattern and grounding pattern in Figure 1. A partially enlarged view, FIG. 5 is a characteristic diagram of lightning potential, and FIG. 6 is a main circuit diagram for explaining the operation of FIG. 3. 1i0~11-3...Sensor, 12-0~12
-4...Transmission line, 16-〇~1B-4...
...Input terminal, 17-θ to 17-4...Wiring pattern, 18...Grounding pattern (conductive member),
19...Multiplexer circuit, 21...
- Signal processing circuit, 23-0 to 23-4... Lightning arrester. Applicant's agent: Kyo Kakinoki Figure 5: Main circuit diagram explaining the operation of Figure 3: Figure 6

Claims (1)

[Claims] A device comprising: a plurality of input terminals connected to a plurality of transmission lines for transmitting external signals; and a signal processing circuit that processes the plurality of external signals inputted from the input terminals. The signal processing device includes: a conductive member that is grounded and placed close to the input terminal; and a conductive member that is connected to the plurality of input terminals and selects a specific signal from the plurality of external signals that are input from the input terminal. A signal processing device comprising: a multiplexer circuit that supplies the signal to the signal processing circuit; and a lightning arrester connected between the multiplexer circuit and the signal processing circuit.