JPH0619064Y2 - Thermocouple input temperature converter - Google Patents

Description

[Detailed Description of the Invention] [Industrial application] The present invention relates to a device for inputting an electromotive force of a thermocouple and converting it into a temperature, and particularly when the temperature of the conversion portion is different from a reference temperature, compensation is performed. Regarding improvement of parts.

[Conventional technology]

The present applicant manufactures a thermocouple-input temperature converter known in, for example, Japanese Patent Application Laid-Open No. 56-31114. The thermocouple input temperature converter converts electromotive force into temperature based on the difference between the temperature Tobs at the measurement end of the thermocouple and the reference temperature (for example, 0 ° C.) Tref. Since it is complicated to always prepare the reference temperature Tref in an ordinary instrument, the difference between the temperature at the instrument-side connection point of the thermocouple and the reference point temperature Tref is measured by the reference junction compensator.

FIG. 5 is a configuration perspective view of a conventional device. The thermocouple input temperature converter has a structure called a card, and is composed of a front plate 10 and a printed circuit board 20, and the reference junction compensator 30 is configured to be attached to a connection terminal block 40 of a thermocouple (not shown). . The electronic circuit mounted on the printed circuit board 20 inputs the thermocouple output voltage connected to the terminal block 40 and the ambient temperature signal of the reference junction compensation unit 30 to obtain a correct measurement value.

FIG. 6 is a cross-sectional view of the essential parts showing the details of the reference contact compensation part. In the figure, 31 is a housing made of an insulating material for the reference contact compensation unit 30, 32 is a temperature sensor fixed inside the housing 31, 33 is a block for fitting the temperature sensor 32 into the housing 31, It is made of a material with a small heat capacity such as aluminum. A bracket 34 is attached to the block 33 and is fixed to the terminal block 40 by elastic force. 41
Is a screw portion of the terminal block 40 made of an insulating material, to which a thermocouple is connected.

[Problems to be solved by the invention]

 However, the conventional device has the following problems.

The temperature sensor 32 has an air layer around the screw portion 41 as well as through the block 33, and if there is a temperature change in the reference contact terminal 41, the temperature of the temperature sensor 33 temporarily does not match.

If the temperature sensor is of a self-heating type like a thermistor, there is a possibility that a temperature gradient will occur between the temperature sensor and the temperature of the screw portion 41.

The configuration of the reference junction compensation unit 30 is complicated and the number of parts is large.

The present invention solves such a problem, and an object thereof is to provide a thermocouple-input temperature converter having a reference contact compensating unit that detects a temperature that matches the temperature of the reference contact terminal with a simple configuration. And

[Means for solving problems]

The present invention which achieves such an object has a connection terminal block to which a thermocouple is connected and a temperature sensor for measuring the temperature of the connection terminal block, and the temperature of the connection terminal block and the reference temperature of the thermocouple. The thermocouple input temperature converter for compensating for the difference between and to obtain the correct thermocouple temperature measurement value has the following configuration.

That is, a material having a high thermal conductivity such as a metal attached to the terminal cover that covers the connection terminal block and connects the temperature sensor and the connection end of the thermocouple to the terminal cover. And a bracket made of the same.

[Action]

 Each component of the present invention has the following functions.

The terminal cover keeps the temperature sensor near the connection terminal block. The bracket acts as a heat conduction path for matching the temperature of the connection terminal block and the temperature of the temperature sensor. As a result, the temperatures at the connection ends of the temperature sensor and the thermocouple match, and temperature compensation can be performed extremely accurately.

〔Example〕

 The present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention.
Incidentally, in FIG. 1, those having the same functions as those in FIG. In the figure, reference numeral 15 denotes a guide plate provided on the periphery of the printed circuit board 20, which acts as a frame structural material of a plug-in unit that can be easily inserted and removed when the structure of the electronic device housing device is a so-called nest structure. Reference numeral 16 is a spring portion provided on the edge of the guide plate 15, and an elastic material such as plastic which can be largely deformed is used. Reference numeral 17 designates the connection terminal block 40 on the printed circuit board 20.
The terminal holding portion that holds the front plate 10 together
Is also used, or is attached to the housing of the electronic device housing device.

Reference numeral 50 denotes a protective cover portion that covers the connection terminal block 40, and rotates in the direction of arrow A about an axis O fixed to the connection terminal block 40. A claw part 42 for restraining the movement of the spring part 16 is formed on one piece of the connection terminal block 40, and the spring part 16 and the claw part 42 are formed.
If the engagement is not released, the protective cover 50 remains closed and the connection terminal block 40 cannot be accessed.

FIG. 2 is an enlarged view of a main part of the protective cover part 50. Reference numeral 51 denotes a cover portion having a U-shaped cross section, which protects the connection terminal block 40 from accidental contact. Reference numeral 52 denotes a bracket whose one end is fixed to the cover portion 51 and which is formed of a material having a high thermal conductivity and a small heat capacity, such as iron. Pressure contact. 53 is a temperature sensor attached to the bracket 52,
4 is connected to the printed circuit board 20. Reference numeral 43 is a thermocouple signal line, which is attached to the screw portion 41.

FIG. 3 is a perspective view of the temperature sensor 53 alone. The temperature sensor 53 is in thermal contact with the bracket 52. As a result, the temperature of the temperature sensor 53 and the temperature of the screw portion 41 to which the thermocouple signal wire is attached are matched by the bracket 52.

Next, the assembling work of the device configured as described above will be described.
FIG. 4 is an explanatory diagram for attaching the thermocouple signal wire to the screw portion 41. Even when the printed circuit board 20 is attached to the nest, the thermocouple signal line can be easily connected by opening the protective cover part 50. Reference numeral 60 is a driver for mounting work.

[Effect of device]

 As described above, the present invention has the following effects.

(1) Bracket 52 for temperature sensor 53 and connection terminal block 40
Since it is thermally connected by using, it has excellent isothermal properties.

(2) Since the reference point compensating section is configured by the protective cover section 50, the structure is simple and the manufacturing cost is reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an essential part of an embodiment of the present invention, FIG. 2 is an enlarged view of an essential part of a protective cover part 50, FIG. 3 is a perspective view of a temperature sensor 53 alone, and FIG. It is explanatory drawing at the time of attaching a thermocouple signal wire to the part 41. FIG. 5 is a perspective view of the configuration of a conventional device, and FIG. 6 is a cross-sectional view of the essential configuration showing details of the reference point compensator. 20 ... Printed circuit board, 40 ... Connection terminal block, 50 ... Protective cover part, 52 ... Bracket, 53 ... Temperature sensor.

Claims (1)

[Scope of utility model registration request] 1. A connection terminal block to which a thermocouple is connected, and a temperature sensor for measuring the temperature of the connection terminal block, wherein the difference between the temperature of the connection terminal block and the reference temperature of the thermocouple is compensated. In a thermocouple input temperature converter for obtaining a correct thermocouple temperature measurement value, a terminal cover to cover the connection terminal block and the temperature sensor is attached, the temperature sensor and the connection end of the thermocouple. A thermocouple input temperature converter, comprising: a bracket made of a material having a high thermal conductivity, such as a metal, attached to the terminal cover to be connected.