CN211978151U

CN211978151U - Cold end box

Info

Publication number: CN211978151U
Application number: CN201922115869.1U
Authority: CN
Inventors: 袁华
Original assignee: Yiwei Technology Chengdu Co ltd
Current assignee: Yiwei Technology Chengdu Co ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2020-11-20
Anticipated expiration: 2029-11-29

Abstract

The utility model relates to a thermocouple detects technical field, and the purpose provides a cold junction box, the utility model discloses a sealed box body, inside PCB circuit board and the PT100 of being provided with of box body, be provided with the cold junction compensator on the PCB circuit board, be provided with on the box body and be used for inserting the panel with thermocouple junction, still be provided with the connector that is used for connecting output module on the box body, insert the panel and be located the inside one end of box body with PCB circuit board connects, PCB circuit board passes through PT100 with the connector is connected, the utility model discloses rational in infrastructure, the practicality is strong, is fit for promoting.

Description

Cold end box

Technical Field

The utility model relates to a cold junction constant temperature detection area, concretely relates to cold junction box.

Background

Two conductors (called thermocouple wires or thermodes) of different compositions are connected in a loop at two ends, and when the temperatures of the two joints are different, electromotive force is generated in the loop, which is called thermoelectric effect, and is called thermoelectric potential. Thermocouples are used for temperature measurement by using the principle, wherein one end directly used for measuring the temperature of a medium is called a working end (also called a measuring end) and the other end is called a cold end (also called a compensation end); the cold junction is connected with display instrument or supporting instrument, and the display instrument can point out the thermoelectrical potential that the thermocouple produced, and the thermocouple is required its cold junction (measuring end is the hot junction, and the end of being connected through the lead wire and measuring circuit is called the cold junction) temperature to keep unchangeable when measuring the temperature, and its thermoelectrical potential size just is certain proportional relation with the measuring temperature. If the temperature of the cold end (environment) changes during measurement, the accuracy of measurement is seriously influenced. Therefore, the compensation end of the temperature sensor must be subjected to temperature compensation correction to ensure the accuracy of temperature measurement.

In the prior art, the cold end is processed by a cold end constant temperature method as follows: placing the cold end of the thermocouple in a constant-temperature device, and when the temperature of the constant-temperature device is 0 ℃; however, the cold end constant temperature method has the following defects that an absolute ice-water mixture is not available, the actual zero temperature is unstable, and the actual cold end error is large; the cold end is added at the position of the ice bottle, so that the maintenance and wiring are troublesome, the frequent replacement is needed, and the maintenance cost is high; the cold junction of the ice bottle needs a thermocouple compensation wire to connect, and the cost of the cable is high.

Therefore, a cold end box is needed, which not only can rapidly measure the temperature of the object to be measured, but also can perform temperature compensation correction on the compensation end of the thermocouple, so as to ensure the accuracy of temperature measurement.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a cold end box, which obtains high stability and even cold end temperature field distribution by evenly arranging an inserting panel and an inserting connector on the box body, and the device has reasonable structure and ingenious design and is suitable for popularization;

in order to achieve the above object, the utility model adopts the following technical scheme: the utility model provides a cold junction box, includes sealed box body, inside PCB circuit board and the PT100 of being provided with of box body, be provided with the cold junction compensator on the PCB circuit board, be provided with on the box body and be used for inserting the panel with thermocouple connection, still be provided with the connector that is used for connecting output module on the box body, it is located to insert the panel the inside one end of box body with PCB circuit board connects, PCB circuit board passes through PT100 with the connector is connected.

Preferably, the patch panel comprises 32 patch channels, and the thermocouple is connected with the patch channels through the quick plug terminal.

Preferably, the connector and the patch panel are located on the same plane of the box body.

Preferably, the output module comprises a cold end digitization module and a signal filtering and conditioning module.

Preferably, the connector is a heavy-duty connector.

Compared with the prior art, the beneficial effects of the utility model are that: convenience of customers inserts the thermocouple and inserts the panel of inserting on the cold junction box, insert and stably be connected between the PCB circuit board of panel and box body inside, evenly distributed is favorable to the heat dissipation, avoids the high temperature to lead to measuring error.

Drawings

FIG. 1 is a top view of a cold end box;

FIG. 2 is a side view of a cold end box in an embodiment of the present invention;

FIG. 3 is an elevation view of a cold end cassette in an embodiment of the present invention;

FIG. 4 is a cross-sectional view of a cold end box in an embodiment of the present invention;

fig. 5 is a view of the inside structure of the cold junction box in an embodiment of the present invention.

1, a box body; 2. a patch panel; 3. a connector assembly; 4. a guide rail.

Detailed Description

The technical solution in the embodiments of the present invention is clearly and completely described below with reference to fig. 1 to 5 of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, those skilled in the art can realize all other embodiments without creative efforts.

In the description of the present invention, it should be understood that the terms "counterclockwise", "clockwise", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description of the present invention, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Fig. 1 is a top view of a cold end box of the present invention;

referring to fig. 1, the heat exchanger comprises a sealed box body 1, a PCB circuit board and a PT100 are arranged inside the box body 1, a cold end compensator is arranged on the PCB circuit board, a plugging panel 2 for connecting with a thermocouple is arranged on the box body 1, a connector 3 for connecting with an output module is further arranged on the box body 1, one end of the plugging panel 2 located inside the box body 1 is connected with the PCB circuit board, the PCB circuit board is connected with the connector 3 through the PT100, the plugging panel 2 comprises 32 plugging channels, the thermocouple is connected with the plugging channels through a quick plugging terminal, the connector 3 and the plugging panel 2 are located on the same side of the box body 1, a guide rail 4 is further arranged on one side of the box body 1 away from the plugging panel 2, and the output module comprises a cold end digitizing module and a signal filtering and conditioning module, the connector 3 is a heavy-duty connector 3.

It is worth noting that one of the basic requirements for measuring temperature using a thermocouple is that the temperature value of one end point must be known. If the temperature of the end can be kept at 0 ℃, the temperature value of the other end point can be directly obtained through a look-up table according to the measured thermoelectric potential. This temperature fixed end is often referred to as the reference end. Theoretically, the thermocouple is measured at the cold end on a 0 ℃ scale. However, the instrument is usually at room temperature during measurement, but the thermoelectric potential difference is reduced due to the cold end not being 0 ℃, so that the measurement is inaccurate and errors occur. The compensation to reduce errors is therefore a cold side temperature compensation.

It should be noted that, in this embodiment, please refer to fig. 3, the box body may achieve the above object by selectively matching the cold end digital output module and the signal filtering and conditioning module, in this embodiment, the box body is set to have a length, a width and a height of 230mm, 129mm and 127mm, and is installed by sliding connection through a 35mm guide rail, the AA-level metering accuracy is better than 0.1 ℃, 3 to 4 AA-level high-precision cold end voting is supported, a plurality of thermocouples such as N, J, K and T types are supported, 32 small thermocouples are connected through a quick plug-in panel, and a gold-plated pin connector has a low contact resistance.

It is worth to be noted that, when a third metal material is connected to the thermocouple loop according to the middle conductor law, which is one of the basic laws of the thermocouple, when the two junctions of the material have the same temperature, the thermoelectric potential generated by the thermocouple remains unchanged and is not affected by the connection of the third metal to the loop. Therefore, when the thermocouple measures temperature, the measuring instrument is connected, the temperature of the measured medium can be known after the thermal electromotive force is obtained, and the cold end box is convenient to detach through the guide rail with reference to fig. 2.

It is worth to be noted that, please refer to fig. 4, thermocouple signals are directly inserted into the plug panel through 32 mini-type galvanic couple quick plugs, circularly symmetric 3 cold ends arranged inside the box body are compensated with a central cold end, a cold end field is sealed by the box body with a double-layer sealing space, temperature is corrected through a metering level high-precision cold end sensor, namely PT100, so that temperature signals on the thermocouple can be accurately read out, when the temperature of a cold end constant temperature area has slight fluctuation, the constant temperature field is sensed through a high-precision platinum resistance sensor, temperature sensing and uploading are dynamically carried out in real time, and a dynamic cold end correction is carried out by the acquisition system. Calculate cold end value and hot junction temperature of developments in real time, solve the unable perception problem of fluctuation of the absolute 0 degree of ice bottle cold junction, according to the cold junction temperature field (please refer to the square space of 5), place 4 cold junction sensors, carry out the homogeneity of temperature field and survey for the inhomogeneity in the monitoring temperature field, and a plurality of cold junction temperatures that outside data acquisition system gathered can lift the hand voting mechanism, the temperature in the constant temperature region of more objective accurate detection, the connector adopts two heavy load connectors, for traditional connected mode, uses heavy load connector to have and installs in advance, and wiring in advance prevents the misplug, improves advantages such as work efficiency.

To sum up, the utility model discloses an implementation principle does: the inserting panel in this embodiment supports 32 passageway multiple type thermocouples, be connected with the warm braw field of cold junction compensation chip and closure through inserting the panel back, when the difference appears in the temperature of platinum resistance discovery cold junction, carry out temperature compensation to the cold junction with the start temperature correction, and through the digital output module of cold junction, convert temperature signal into digital signal and be used for showing the temperature of thermocouple hot junction, high stability and even cold junction warm field distribution in the cold junction box, the temperature value of cold junction output has been guaranteed, be used for replacing traditional ice bottle or electron constant temperature tank, provide the high accuracy cold junction sensor of measurement level, realize temperature cold junction warm field evenly distributed and high accuracy thermocouple measurement.

Claims

1. The utility model provides a cold junction box, its characterized in that, including sealed box body (1), box body (1) inside is provided with PCB circuit board and PT100, be provided with the cold junction compensator on the PCB circuit board, be provided with on box body (1) and be used for inserting panel (2) with thermocouple junction, still be provided with on box body (1) and be used for connecting output module's connector (3), it is located to insert panel (2) box body (1) inside one end with PCB circuit board connects, PCB circuit board passes through PT100 with connector (3) are connected.

2. A cold end cassette according to claim 1, wherein the patch panel (2) contains 32 patch channels to which thermocouples are connected by quick-connect terminals.

3. A cold end cassette according to claim 1, wherein the connectors (3) and patch panels (2) are located in the same plane of the cassette body (1).

4. A cold end cassette according to claim 3, wherein the cassette body (1) is further provided with rails (4) on the side remote from the patch panel (2).

5. The cold end cartridge of claim 1 wherein said output module comprises a cold end digitizing module and a signal filtering conditioning module.

6. A cold end cassette according to claim 1, wherein said connector (3) is a heavy duty connector (3).