JPH0572016A - Transmitter with temperature output - Google Patents

Abstract

(57) [Summary] [Purpose] A liquid level transmitter that measures the liquid level of the fluid to be measured. A temperature sensor is incorporated in the liquid contact flange to measure the liquid level and temperature simultaneously with a single liquid level transmitter. It will be possible to expand the temperature measurement points by simply replacing the standard level liquid level transmitter with the plant already in operation. [Structure] A hole through which a temperature sensor 2 is inserted is opened in a liquid contact flange 3 of a transmitter body 1, and a gasket, a collar and a nipple are fixed and sealed through the temperature sensor 2. The lead wire of the temperature sensor 2 is incorporated inside the transmitter body 1 so that the liquid level signal and the temperature signal do not affect each other and can be taken out together.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitter for measuring a liquid level of a fluid to be measured.

[0002]

2. Description of the Related Art In order to monitor and control the state of a fluid to be measured in tanks, pipes, etc., internal liquid level, temperature, flow rate and pressure are measured. In particular, in order to monitor and control the state of the fluid to be measured in the tank, it is necessary to measure the internal liquid level and the temperature.

In the prior art, a dedicated nozzle for measuring the liquid surface level for measuring the liquid surface level and a nozzle for measuring the temperature for measuring the temperature are provided in the tank, and the liquid level gauge and the thermometer are separately attached.
The wiring was used to measure the liquid level and temperature.

[0004]

The above prior art is a tank in which only the liquid level is measured after the plant is in operation.
There is no consideration when it becomes necessary to measure temperature, and when adding temperature measurement points, there is a problem that a dedicated nozzle for temperature measurement cannot be installed in the tank unless the plant is stopped for a certain period of time. there were.

The present invention incorporates a temperature sensor into the liquid contact flange of a liquid level transmitter for measuring the liquid level of a fluid to be measured, so that when temperature measurement points are added, the liquid level transmission incorporating the temperature sensor is incorporated. The purpose is to easily increase the temperature measurement points by simply replacing the existing liquid level transmitter with the temperature measuring device. Furthermore, the process of adding temperature measurement points can be shortened and the construction cost can be reduced.
The purpose is to provide ease of construction.

[0006]

In order to achieve the above object, a temperature sensor is incorporated in a liquid contact flange of a liquid level transmitter so that the temperature can be measured.

Further, by incorporating the lead wire of the temperature sensor into the liquid level transmitter and connecting it to a circuit in the liquid level transmitter, the output signal of the temperature sensor can be taken out from the terminal box of the liquid level transmitter. It was done. Therefore, from the terminal box of the liquid level transmitter, the liquid level signal and the temperature signal
It becomes possible to take out one signal individually.

Further, the output of the temperature sensor is A / D converted inside the liquid level transmitter and superposed on the output of the liquid level so that the liquid level signal and the temperature signal can be simultaneously output on one line. Will be possible.

Further, the protruding position of the temperature sensor incorporated in the liquid contact flange is provided outside the welding position of the diaphragm of the liquid contact flange and inside the inner diameter of the gasket used for mounting the liquid level transmitter, so that the existing standard The temperature measurement points can be expanded simply by replacing the liquid level transmitter with the specified specifications.

Further, in order to improve the accuracy of temperature measurement, the heat-sensitive portion of the temperature sensor is projected from the liquid contact flange surface of the transmitter toward the fluid to be measured.

Further, the temperature sensor protruding toward the fluid to be measured is fixed, and the temperature sensor is fixed and sealed using a packing, a collar and a nipple in order to maintain the airtightness of the liquid contact flange.

[0012]

The temperature sensor is incorporated in the liquid contact flange of the liquid level transmitter, and its heat-sensitive portion projects from the liquid contact surface of the liquid contact flange toward the fluid to be measured and is in direct contact with the fluid to be measured. By providing the position where the temperature sensor protrudes outside the welding position of the diaphragm of the liquid contact flange and inside the inner diameter of the gasket used when mounting the liquid level transmitter, the temperature sensor can be operated without impairing the function of the liquid level transmitter. Since the projecting part of is placed inside the nozzle on the tank side, it is possible to add temperature measurement points without modifying the installation location of the existing liquid level transmitter.

The temperature sensor is a packing, a collar,
Since it is fixed to the liquid contact flange by the nipple and is sealed between the liquid contact flange and the liquid contact flange, there is no influence of providing the temperature sensor built-in hole in the liquid contact flange.

The lead wire of the temperature sensor is taken inside the liquid level transmitter and connected to the internal substrate. Although the connection part is on the substrate of the liquid level transmitter, if electrically insulated, the individual circuits do not affect each other, so the liquid level signal and the level signal from the terminal box of the liquid level transmitter can be separately provided. The temperature level signal can be retrieved.

Further, the output of the temperature sensor is A / D converted by a circuit in the liquid level transmitter and superposed on the analog liquid level signal, so that the liquid level signal and the temperature level signal are taken out by one line. be able to. At this time, if the magnitude of the digital signal output from the temperature sensor is made sufficiently smaller than the analog signal output from the liquid level transmitter, the two signals can be taken out simultaneously without affecting each other. .

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is an overall structural view of a sanitary liquid level transmitter for measuring the liquid level of a fluid to be measured. In addition, FIG.
[Fig. 2] is a detailed view of a sectional structure of a portion A of Fig. 1.

A hole for passing the temperature sensor 2 is formed in the liquid contact flange 3 of the transmitter body 1, and the heat sensitive portion of the temperature sensor 2 is projected from the liquid contact surface 4 toward the fluid to be measured. At this time, all the heat-sensitive parts of the temperature sensor 2 must protrude from the liquid contact surface 4 toward the fluid to be measured. This is because when the heat-sensitive part of the temperature sensor 2 is in contact with the liquid contact flange, the liquid contact flange 3 serves as a heat dissipation piece and the correct temperature of the fluid to be measured cannot be measured.

The temperature sensor 2 is installed at a position outside the welding position of the liquid contact flange 3 and the diaphragm 5,
Further, it is inside the inner diameter of the gasket that seals between the liquid contact flange 3 and the nozzle provided in the tank. Also,
A gasket 6, a collar 7 and a nipple 8 are used to fix the temperature sensor 2 and ensure airtightness as the liquid contact flange 3. The gasket 6, the collar 7, and the nipple 8 can maintain the airtightness that the liquid contact flange 3 originally has, without impairing the function of the conventional sanitary liquid level transmitter. Therefore, there is an effect that the temperature measurement points can be increased without modifying the nozzle provided in the tank of the plant simply by replacing the existing standard type sanitary liquid level transmitter.

Further, the lead wire of the temperature sensor 2 is taken into the central portion of the transmitter body 1 and soldered to the internal substrate. The soldering part is on the substrate of the transmitter body 1,
It is electrically insulated from the circuit as a sanitary liquid level transmitter. Therefore, although the circuits are on the same board,
Since they are separate circuits, the liquid level signal and the temperature signal can be taken out without affecting each other. Further, since the input / output terminal of the sanitary liquid level transmitter and the input / output terminal of the temperature sensor 2 are provided together while being insulated from the terminal plate of the transmitter main body 1, the temperature sensor 2 when wiring to the transmitter main body 1 Can also be wired.

When the lead wire of the temperature sensor 2 is taken into the transmitter body 1, the holder 9 is welded to the transmitter body 1 to secure the airtightness of the transmitter body 1, and the cover 1
The O-ring is sealed inside the 0.

[0022]

According to the present invention, when it is necessary to add a temperature measuring point to a tank in a plant which is already in operation, the tank of the present invention can be simply replaced with an existing standard level liquid level transmitter. Since the temperature measurement points can be added without modifying the nozzle provided in the above, there is an effect of shortening the process of adding the temperature measurement points and reducing the construction cost.

Further, since the liquid level signal and the temperature signal can be simultaneously taken out from the terminal box of the liquid level transmitter without affecting each other, there is an effect of shortening the wiring work process and reducing the construction cost.

[Brief description of drawings]

FIG. 1 is a front view and a bottom view of a sanitary liquid level transmitter with temperature output according to an embodiment of the present invention.

FIG. 2 is a detailed view of a sectional structure of a portion A of FIG.

[Explanation of symbols]

1 ... Transmitter body, 2 ... Temperature sensor, 3 ... Wetted flange, 4 ... Wetted surface, 5 ... Diaphragm, 6 ... Gasket,
7 ... Color, 8 ... Nipple, 9 ... Holder, 10 ... Cover.

Claims (4)

[Claims] 1. A flanged liquid level transmitter for measuring a liquid level of a fluid to be measured, wherein a temperature sensor is incorporated in a liquid contact flange for attaching the liquid level transmitter to a plant tank, piping, etc. A transmitter with temperature output that can measure the liquid level and temperature of a single fluid. 2. A transmitter with temperature output, characterized in that the liquid level signal output and the temperature signal output can be taken out separately from the terminal box of the liquid level transmitter through separate circuits. 3. A transmitter with temperature output, wherein two signal outputs are taken out by one line by digitizing and superimposing the temperature signal output on an analog liquid level signal. 4. When a standard level liquid level transmitter is attached to a plant tank, piping, etc., a temperature signal can be obtained by simply replacing the standard level liquid level transmitter. Transmitter with output.