JPS5826361Y2 - thermocouple thermometer - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a thermocouple type thermometer mainly used for measuring temperature inside a vacuum chamber.

Conventionally, this type of thermometer has been provided with a frame housing having a removable cap on the upper surface surrounding the longitudinal protective tube that houses the thermocouple, and a protective housing that protrudes downward from the frame housing. A type is known in which a guide tube on the outer periphery of the root of the tube is inserted into a measurement hole in the earthen wall of a vacuum chamber to form an airtight connection. The atmosphere is communicated with the vacuum chamber through the vacuum chamber, and the atmosphere becomes equivalent to the atmosphere inside the vacuum chamber, so that metal vapor and other harmful components in the atmosphere are transferred from inside the frame to the inside of the protection tube through the upper end of the protection tube that opens into it. It acts on the thermocouple inside the thermocouple and tends to change its characteristics, and its service life is relatively short, for example, about 30 hours, and therefore it is easy to cause measurement errors and the thermocouple There are inconveniences such as having to replace the parts frequently.

The purpose of the present invention is to obtain a thermometer free of such inconveniences, and the purpose of the present invention is to attach a removable cap 3 to the base of a long protection tube 2 that houses a thermocouple 1, surrounding it.
A frame casing 4 having
In a type that is inserted into a measurement hole formed in the upper wall cK and sealed airtightly, the measurement hole provided in the upper wall C of the vacuum chamber a has a spiral portion d formed on the upper outer periphery; It is composed of a cylindrical protruding part e having an O-ring 15 on its inner periphery, and the O-ring 15 is pressed by a nut 16 screwed into the spiral part d. A slidable and fixed stopper 14 is provided, and the stopper 14
so that the nut 16 is supported on the upper surface of the frame housing 4.
The inside is airtightly isolated from the inside of the guide cylinder 5 by its bottom wall 6.

The frame casing 4 is made up of upper and lower halves 4a, 4a, which overlap each other via an O-ring 7 on their opposing surfaces and are connected together with screws 8 to form an airtight structure, and the cap 3 is formed on the opposing surfaces. A KO ring 9 is interposed between the thermocouple 1 and the thermocouple 1 to close the thermocouple 9 airtightly. shall be taken as a thing.

Although this point is not particularly different from the conventional one, according to the present invention, the frame casing 4 is provided with an integral bottom wall 6 to airtightly isolate the inside of the frame casing 4 from the inside of the guide cylinder 5 below.

To explain this in detail, the guide tube 5 is fitted into the recess 11 on the lower surface of the bottom wall 6 without penetrating it, and is fixed by welding or other means, and the protective tube 2 is fixed at the center of the bottom wall 6. Although it is inserted vertically, the insertion hole is hermetically closed by an O-ring 12 on the outer periphery of the upper surface and a flange 13 on the upper surface.

In the drawing, 14 is a stopper, 15 is O on the outer periphery of the lower end of the guide tube 5.
The ring 16 indicates a cap-shaped nut on its upper surface.

To explain its operation, the temperature inside the vacuum chamber a is detected by the thermocouple 1 inside the protection tube 2, and this point is not particularly different from the conventional one. The cap 3 is once opened to introduce the atmosphere, and then the cap 3 is closed to enclose the atmosphere. In other words, the inside of the frame casing 4 does not communicate with the guide cylinder 5 below, and therefore The atmosphere in the vacuum chamber a is not applied to the thermocouple 1 in the protective tube 2 whose upper end is opened in the frame casing 4. As a result, its service life is significantly increased.

Furthermore, it is conceivable that the protective tube 2 may be accidentally damaged during its use, but in this case, the atmosphere inside the frame casing 4 will only be introduced into the vacuum chamber a, and the pressure will therefore be increased to some extent. However, it is quickly removed by the subsequent operation of the vacuum pump, and thus the interior of the vacuum chamber a can be maintained at a predetermined degree of vacuum.

In this way, according to the present invention, the inside of the frame casing 4 connected to the upper end of the protective tube 2 housing the thermocouple 1 is isolated from the inside of the guide tube 5 on the lower side at the bottom wall 6, and the cap 3 on the top surface thereof is isolated. The thermocouple 1 is isolated from the atmosphere and kept in a sealed state with the atmosphere, and is used in this state.Therefore, the thermocouple 1 is not affected by harmful components in the atmosphere within the vacuum chamber a or by the outside atmosphere. , has the effect of being able to be used stably over a long period of time.

In addition, the thermocouple 1 can be mounted in a predetermined position by simply screwing together the helical part dK nut 16 of the cylindrical protrusion e and fixing the stopper 14 on the outer periphery of the guide tube 5. This has the effect that the position of the thermocouple 1 can be adjusted simply by changing the .

[Brief explanation of the drawing]

The drawing is a cutaway side view of the thermometer according to the present invention, with part of -flJ removed. 1...Thermocouple, 2...Resuscitation tube, 3...
...Cap, 4...Frame housing, 5...
Guide cylinder, a...Vacuum chamber, b...Measurement hole, 6...Bottom wall, C...Top wall, d...
...Spiral part, e...Cylindrical protrusion, 14...
...Stopper 15...0 ring, 16...
...Natsuto.

Claims (1)

[Scope of utility model registration request] A frame housing 4 having a removable cap 3 on the upper surface surrounding the long protection tube 2 that houses the thermocouple 1 is provided at the root of the long protection tube 2 that houses the thermocouple 1, and the protection tube 2 projects downward from the frame housing 4. In a guide cylinder 5 on the outer periphery of the root, the measurement hole formed in the upper wall C of the vacuum chamber a is inserted into the measurement hole and sealed airtightly. A spiral part d is formed on the outer periphery of the upper part, and the cylindrical protrusion part e has an O-ring 15 on the inner periphery. west,
The guide tube 5 is provided with a stopper 14 on its outer periphery that can be slid and fixed in the length direction, and the stopper 14 allows the nut 1 to be fixed.
6, and the inside of the frame housing 4 is airtightly isolated from the inside of the guide tube 5 by the bottom wall 6.