JPH08249045A - Signal switching device - Google Patents

Abstract

(57) [Abstract] [Purpose] Simplification of the transmission line that distributes many input signals,
It aims at cost reduction. [Structure] A plurality of signal switching devices each having a plurality of input terminals and output terminals are prepared.
It is characterized in that the output terminal is connected to one input terminal of another signal switch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal switching device used in a remote monitoring system or the like.

[0002]

2. Description of the Related Art A remote monitoring system is used for monitoring factories, blast furnaces, dams, etc. for the purpose of centralized control at monitoring stations. FIG. 3 is a diagram showing an example of a conventional remote monitoring system of this type. In the figure, a block A surrounded by a dotted line is a first site, a block B is a second site, and a block A ′ is a first site. The block B'is the second monitoring station. Further, 10 to 15 are signal generation sources that generate signals via a television camera and various sensors, 20 to 23 are signal repeaters for compensating for signal attenuation when the signal generation source is in a remote place, and 30, 31 are A signal switcher for selecting a desired signal from a plurality of signals, 40 is a signal distributor for distributing the same signal to a plurality of transmission lines, and 50 to 54 are monitors.

In the remote monitoring system shown in FIG. 3, the site A is monitored at the monitoring station A'and the site B is monitored at the monitoring station B '. A monitor switches the signal switching devices 30 and 31 to which monitor the signal of 1 is reproduced. Further, when it is desired to monitor the site B at the monitoring station A ′, the signal selected by the signal switch 31 is distributed by the signal distributor 40 and reproduced on the monitor 52.

FIG. 4 is a block diagram showing an example of a conventional signal switching device used in the system shown in FIG.
Each of the signal switchers 30 and 31 has four inputs and two outputs, respectively. As shown in FIG. 4, each supervisor 70, 7
1 operates the respective controllers 60 and 61 to select a desired input signal from the input signals 1 to 4 and reproduces it on the respective monitors 50 and 53. The signal distributor 40 is used when it is desired to monitor a signal.

[0005]

As described above, the signal switching device in the remote monitoring system has a simple structure in which signal switching devices for selecting independent signals are arranged in parallel, and therefore, the signal switching device is input to another signal switching device. Signal cannot be selected. Therefore, if the number of input signals increases in a system configured for this purpose, a special signal switcher with a large number of input terminals must be prepared.
High cost. Further, there is a problem that a signal distributor must be used when it is desired to monitor a signal input to another signal switching device as described above.

The present invention has been made to solve the above problems, and an object thereof is to provide a signal switching device capable of efficiently switching signals in the system as described above.

[0007]

A signal switching device according to the present invention prepares a plurality of signal switching devices each having a plurality of input terminals and output terminals, and one output terminal of each signal switching device switches another signal. It is characterized by being connected to one input terminal of the container.

Further, it is characterized in that switching control of each signal switching device can be simultaneously performed by the same control signal.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, the same symbols as in FIG. 4 indicate the same or corresponding parts. As shown in FIG. 1, the signal switching device of the present invention prepares a plurality of signal switching devices having a plurality of input terminals and output terminals (in the example shown in FIG. 2 units), one output terminal of each signal switching device is connected to one input terminal of another signal switching device.

Therefore, if any one of the input signals 1 to 3 input to the signal switch 30 is selected and switched so as to be output to the output terminal 2, this output is input to the input terminal 1 of the signal switch 31, Further, if the signal switch 31 is controlled to select the input signal 1 and connect it to the output terminal 2, the monitor 53 inputs the input signals 1 to 3 input to the signal switch 30.
Can be selected and reproduced, and any of the input signals 2 to 4 input to the signal switcher 31 itself can be selected and reproduced, and the monitor 53 can reproduce six input signals. Similarly, the monitor 50 can also reproduce six input signals, that is, the input signals 1 to 3 input to the signal switch 30 and the input signals 2 to 4 input to the signal switch 31. Further, for example, the input signals 1 to 3 input to the signal switch 30 are input.
Is connected to its output terminals 1 and 2, and the input terminal 1 of the signal switch 31 is connected to its output terminal 2, the same signal can be reproduced on the monitors 50 and 53 without using a signal distributor.

In the above embodiment, the description has been made with the combination of two signal switching devices each having two output terminals. However, this type of signal switching device normally has the same number of output terminals as the number of input terminals. Therefore, in the actual configuration, an output terminal not used in the system may be connected to one input terminal of another signal switch, and there is no particular disadvantage due to the limited number of output terminals. Further, the number of signal switching devices to be combined is not limited, and may be two or more as shown in FIG.

Further, in the apparatus shown in FIG. 1, the signal switching devices 30 and 31 are separately controlled to be controlled by the respective controllers 60 and 61, but all the respective controllers use the same control signal. If the configuration is such that the switching control of the signal switching device can be performed at the same time, a more convenient device can be configured. Further, in the above-mentioned embodiment, the case of using it in the remote monitoring system has been described, but it goes without saying that it can be widely used for the same purpose.

[0013]

As described above, the signal switching device of the present invention can configure a system using a normal signal switching device having a small number of terminals even when the number of input signals is large, and further includes a signal distributor. The same signal can be reproduced on the monitor without need, and the system can be simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram showing another embodiment of the present invention.

FIG. 3 is a block diagram showing an example of a conventional remote monitoring system.

FIG. 4 is a block diagram showing an example of a conventional signal switching device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinichiro Koga 5-1-1 Shimorenjaku, Mitaka City, Tokyo Japan Radio Co., Ltd.

Claims (2)

[Claims] 1. A configuration in which a plurality of signal switching devices each having a plurality of input terminals and output terminals are prepared, and one output terminal of each signal switching device is connected to one input terminal of another signal switching device. Signal switching device. 2. The signal switching device according to claim 1, wherein the switching control of each of the signal switching devices can be performed simultaneously with the same control signal.