JPH05282586A - Signal transmitter - Google Patents

Abstract

PURPOSE:To realize a signal transmitter with good operability by arranging screw terminals and a connector for connecting an adjustment tool on one straight line. CONSTITUTION:A cylindrical case 1 has space for containing a signal converter part(mainbody) for converting a signal inside it and a cover 2 is fixed by a screw 21 at the upper end part of the case 1. A terminal block 3 for electrically executing an input/output wiring to the outside of the case 1 and the signal converter part contained inside the case is constituted of the plural screw terminals. Moreover, the connector 4 which connects the adjustment tool(hand- held terminal, etc., for example) for adjusting the signal converter part which is contained inside the case is provided. Then, the temrinal block for electrically executing the input/output wiring and the connector 4 are constituted so as to be arrayed on the one straight line.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal transmission device for converting a signal from a temperature sensor such as a thermocouple or a resistance temperature detector installed in a process into a standardized signal for transmission. More specifically, the signal converter part (main body) that converts signals is housed in a protective case, and the connection terminals (screw terminals) for input wiring and output wiring are provided on the case cover. The present invention relates to a transmission device.

[0002]

2. Description of the Related Art As a signal converter or a signal transmission device for converting signals from various sensors into standardized signals and transmitting them, for example, Yokogawa Technical Report Vol. 32 No. 4 (1988), No. 53. Pp. 58-58. FIG. 6 is a perspective view showing an external configuration of the signal converter shown here. This signal converter is configured so that it can be used by fixing it to the panel or wall of the instrument room. The box-shaped housing houses the electric circuit part, and the screws for connecting the input wiring to the front of the housing. A terminal T1 and a screw terminal T2 for connecting the output wiring are provided, and an adjustment tool (for example, a handheld terminal) that electrically adjusts the signal converter (for example, range adjustment) from the outside between the screw terminals T2. ) Is connected to the connector CC.

[0003]

In a signal converter that is supposed to be mounted on a panel, a large number of converters can be mounted continuously in the lateral direction by having such a housing structure. Moreover, since the wiring space is provided in the vertical direction, the input / output wiring can be facilitated.
The adjustment tool connections are also accessible from the front of the converter.

By the way, when such a signal converter is installed outdoors, it is necessary to house the electric circuit portion in a waterproof case or the like. Further, it may be difficult to secure a sufficient wiring space for the input / output wiring, and it is required that the cable drawing direction of the input / output wiring can be freely selected. Therefore, there is a problem that the signal converter having the structure as shown in the related art cannot cope with the problem.

The present invention has been made in view of the above circumstances, and the direction of pulling out the input / output wiring cable can be freely selected, and these input / output wirings interfere with the connection (connector access) of the adjustment tool. It is an object of the present invention to provide a signal transmission device having a structure that can be easily accommodated in a waterproof field case without doing so.

[0006]

SUMMARY OF THE INVENTION The present invention to achieve such an object is to provide a case for accommodating a signal converter portion (main body) for converting a signal, a case mounted on an upper end portion of the case, and an external case. And a printed wiring board on which terminals for electrically connecting to the signal converter portion are installed, and a plurality of screw terminals for connecting to the signal converter portion and electrical adjustment of the signal converter portion are provided. The signal transmission device is characterized in that it is arranged so as to be in a straight line with a connector for connecting the adjustment tool.

[0007]

The input wiring cable and the output wiring cable are not specified depending on their usage patterns, such as when they are pulled out in opposite directions or when they are pulled out in the same direction. The input / output wiring terminal block consisting of screw terminals and the adjustment tool connector are arranged in a straight line, and the input wiring cable and output wiring cable can be moved in the same direction or in opposite directions from the screw terminals. Can be pulled out.
Further, even when the connector is connected, the wiring cables and the connector can be prevented from interfering with each other.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an external perspective view of a signal transmitter according to the present invention, and FIG. 2 is a configuration diagram of the signal transmitter according to the present invention.
(A) is a plan view, (b) is a front view, and (c) is a side view. In these figures, reference numeral 1 denotes a cylindrical case having a space for accommodating a signal converter portion (main body) for converting a signal therein. Reference numeral 2 denotes a cover, which is fixed to the upper end of the case 1 with a screw 21. Reference numeral 3 denotes a terminal block for performing electrical wiring for input / output to / from the signal converter portion housed inside the case 1 and inside the case, and is composed of a plurality of screw terminals. Reference numeral 4 denotes a connector for connecting an adjustment tool (for example, a handheld terminal) for adjusting the signal converter portion housed inside the case.
The terminal block 3 for electrical wiring for input and output and the connector 4 are arranged in a straight line.

FIG. 3 is an assembly configuration diagram between the case 1 and the cover 2. Here, the signal from the thermocouple is input and the signal is converted. In the figure, reference numeral 5 denotes a printed wiring board, which is provided with a soaking pattern 51 on the substrate where the input / output terminal block 3 is installed. Further, on this soaking pattern 51 for cold junction compensation of a thermocouple Temperature detection sensor 5 for detecting terminal temperature
2 is installed. The cover 2 is provided with a rectangular hole 22 through which the input / output terminal block 3 portion penetrates, and the connector 4 is provided adjacent to the rectangular hole 22. Although there is a cable for electrically connecting the connector 4 and the printed wiring board 5, they are omitted here.

As shown in the drawing, the cover 2 sandwiches the printed wiring board 5 between the cover 2 and the case 1 so that the terminal block 3 portion penetrates the rectangular hole 22 of the cover 2 and projects to the outside. Attached to. FIG. 4 shows case 1
It is a circuit block diagram which shows an example of the electric circuit accommodated in. Here, the circuit assumes a signal transmission device for transmitting a temperature signal, and a temperature sensor such as a thermocouple or a resistance temperature detector is connected to the input wiring terminals 3a to 3c. Further, a two-wire type transmission line LN for supplying power and transmitting signals is connected to the output terminal wirings 3d to 3e.

Reference numeral 31 is a signal of each of the input wiring terminals 3a to 3c,
A multiplexer for selecting and fetching a signal from the temperature detection sensor 52 for cold junction compensation, 32 is A / D conversion means for converting the signal selected by the multiplexer into a digital signal, and 33 is converted by A / D conversion means. It is a microprocessor for inputting digital signals. The microprocessor 33 controls the multiplexer and the A / D conversion means and performs arithmetic processing such as linearization,
The calculation result is output as a pulse width signal.

The pulse width signal output from the microprocessor 33 is converted into a current signal through the pulse width / voltage signal converting means 35 and the voltage / current converting means 36 after the signal is insulated by the photo coupler 34. And is applied to a transistor (FET) Q0 which is a current control means. The transistor Q0, which is the current control means, is a two-wire transmission line LN.
The current flowing through is controlled in the range of, for example, 4 to 20 mA that is standardized.

The connector 4 to which the adjustment tool is connected is connected to the microprocessor 33, and an external adjustment tool allows calculation formulas and constants of arithmetic processing in the microprocessor 33 to be set to, for example, the type and range of the sensor. It is configured so that it can be set and changed accordingly. The operation of the device configured as described above will be described below.

FIG. 5 shows a case 1 accommodating a signal transmission device.
It is a block diagram in the case of accommodating (this is called an internal unit) in a field case of a waterproof structure for installing outdoors. The field case 10 is provided with wiring ports 11 and 12 through which wiring cables are taken in and out, facing each other. First, the input wiring and the output wiring cable are inserted from the wiring port 11 or 12, and the outer side wall of the inner unit 1 Each wiring cable is started up so that it can be transmitted, and is connected and fixed to the corresponding screw terminal of the screw terminal block 3 exposed on the cover 2 of the internal unit. Here, the direction of input wiring and output wiring is
In many cases, the cables are pulled out in mutually opposite directions, or when they are pulled out in the same direction, they are not specified depending on the usage form. Therefore, in consideration of workability at the site, the wiring cable is inserted from the wiring port in the direction in which the work can be performed most easily.

Further, in the signal transmission device of the present invention, since the screw terminal block 3 is located at the center of the upper part of the case,
Each wiring cable does not become entangled with respect to the wiring cable from either direction of the wiring ports 11 and 12.
Can be connected and fixed to the corresponding screw terminal. Also,
Even after connecting and fixing each wiring cable to the corresponding screw terminal, since the connector 4 is arranged in a straight line with the screw terminal block 3, each wiring cable which has already been wired is connected to the connector 4 part. It doesn't even cover. Therefore, after housing the inner unit 1 in the field case 10,
Even when the adjustment tool is connected to the connector 4, the wiring cables do not interfere with each other, and smooth connection work is possible.

When the adjustment work by the adjustment tool is completed,
Cover the lid 13 of the field case 10 on the inner unit 1 part,
Fix both. In addition, the wiring port into which the cable is not inserted and the gap between the cable and the wiring port are closed with a waterproof adhesive or the like. With such a configuration, when the signal transmission device is installed outdoors, the screw terminal portion, the connector portion, and the internal electric circuit portion can be protected from the intrusion of dew condensation or raindrops.

In the above embodiment, the electric circuit accommodated in the internal unit is supposed to transmit a two-wire type temperature signal, but a transmission for transmitting a signal from another sensor. It may be a device.

[0018]

As described in detail above, according to the present invention, the screw terminal and the connector for connecting the adjusting tool are arranged in a straight line, and the wiring cable is arranged in both directions of the screw terminal. The connector and the wiring cable do not interfere with each other even when connecting the adjustment tool, and the signal transmission device has good workability during on-site installation and maintenance. Can be realized.

[Brief description of drawings]

FIG. 1 is an external perspective view of a signal transmitter according to the present invention.

FIG. 2 is a configuration diagram of a signal transmitter according to the present invention, (a)
Is a plan view, (b) is a front view, and (c) is a side view.

FIG. 3 is an assembly configuration diagram between a case and a cover.

FIG. 4 is a circuit block diagram showing an example of an electric circuit housed in a case.

FIG. 5 is a configuration diagram of a case in which a case containing a signal transmission device is housed in a field case having a waterproof structure for installing outdoors.

FIG. 6 is a perspective view showing an external configuration of a conventional signal converter.

[Explanation of symbols]

 1 Case 2 Cover 3 Terminal Block 4 Connector 5 Printed Wiring Board 51 Soaking Pattern 52 Temperature Detection Sensor

Claims (4)

[Claims] 1. A signal converter portion (main body) for converting a signal.
And a printed wiring board mounted on the upper end of the case and provided with terminals for electrical connection to the outside of the case and the signal converter portion. A signal transmission device, characterized in that a plurality of screw terminals for performing the above and a connector for connecting an adjustment tool for electrically adjusting the signal converter portion are arranged in a straight line. 2. A screw terminal block portion composed of a plurality of screw terminals has a rectangular hole penetrating therethrough, and a connector is provided with a cover provided adjacent to the rectangular hole, and the cover is printed wiring. The signal transmission device according to claim 1, wherein the signal transmission device is mounted on the upper end of the case with the substrate sandwiched therebetween. 3. An input signal for signal conversion is a signal from a thermocouple, and a soaking pattern is provided on a printed wiring board,
2. The signal transmission device according to claim 1, wherein a temperature detection sensor for compensating for the cold junction of the thermocouple is provided on the soaking pattern. 4. A field case having a wiring port in a facing portion is provided, and a case for accommodating a signal converter part (main body) has a screw terminal block portion composed of a plurality of screw terminals at the center of two wiring ports. The signal transmission device according to claim 1, wherein the signal transmission device is installed in the field case so as to be located at.