JPS5841462Y2 - temperature sensor - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a temperature sensor in which a protective tube, into which a detection element such as a thermocouple is inserted and filled with an inorganic insulating material, is fixed to a terminal box.

Conventionally, in this type of filled-type temperature sensor, a detection element such as a thermocouple wire inside a protection tube must be accurately fixed to a terminal of a terminal box.

For this reason, conventionally, as shown in FIG. 6, a threaded part 31a is formed on the inner surface of the holding part 31 of the terminal box body 2a, and the threaded part 4a at the upper end of the protective tube 4 is screwed into the threaded part 31a of the holding part 31. The protective tube 4 was fixed to the terminal box main body 2a by screwing the nut 32 onto the threaded portion 4a of the protective tube 4 inside the terminal box.

In order to prevent the protective tube 4 from rotating, the holding portion 31
The protective tube 4 was fixed from the side with a set screw 31b or the like.

However, since the diameter of the protective tube 4 varies in size, it cannot necessarily be fixed with the setscrew 31b, and the threaded portion 31a may be damaged, and the locking effect is weak.

The purpose of this idea was made in view of the above points.
A temperature sensor is provided in which a fitting member such as a nut is fixed to the protective tube by welding or the like, and this fitting member is fitted and fixed to the holding part of the terminal box to prevent the protective tube from rotating. It is to provide.

Next, an embodiment of this invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of the terminal box according to this invention, and FIG. 2 is a perspective view showing the lid in an open state.

In the figure, 1 is a temperature sensor body, and this sensor body 1 has a terminal box 2 in the upper part and a protective tube 4 in which the thermocouple wire 3 is inserted in the lower part, and the terminal box 2 has a terminal box body 2a. and a lid body 2b.

The lid 2b is connected to the terminal box main body 2a by a hinge 5 so as to be openable and closable, and the lid 2b and the terminal box main body 2a are removably fixed by a lid fixing screw 15,
A terminal board 7 made of an insulating material such as ceramics, and conductive terminal blocks 8, 8 placed and fixed on the terminal board 7 are provided in the main body internal space 6 of the terminal box main body 2a.

Further, a stepped portion 9 is formed on the upper surface of the terminal box main body 2a along the outer periphery of the main body 2a, and a raised portion 10 is formed around the internal space 6 of the main body by this stepped portion 9.

Furthermore, a conductor lead-out portion 11 is formed protruding from the other end of the hinge 5 in the terminal box 2, and a wire insertion portion 12 is formed at the tip of the conductor lead-out portion 11a on the terminal box body 2a side. At the same time, a drip-proof backing 13 made of a relatively hard rubber material is attached between the insertion portion 12 and the internal space 6.

A thread is formed on the inner periphery 12a of the wiring insertion portion 12, and is removably screwed into the wiring tube 14, and the center position of the diameter of the wiring insertion portion 12 is approximately the same as the top surface of the terminal box body 2a. It is made to match.

Furthermore, an opening groove 17 having a width that allows the conductor 16 to pass through is formed along the axial direction of the insertion part 12 at the upper end of the insertion part 12, and the conductor on the lid body 2b side corresponding to the opening groove 17 A protrusion 18 that is removably fitted into the opening groove 17 is formed on the side of the drawer 11b.

An insertion portion 12 is provided on the surface of the protruding portion 18 on the terminal box body 2a side.
Since the curvature is the same as that of the inner circumference 12a of the wiring insertion portion 12, the inner circumference 12a of the wiring insertion portion 12 has a perfect cylindrical shape when the lid body 2b is closed.

Further, a lid internal space 19 is formed in the lid 2b corresponding to the main body internal space 6, and this lid internal space 1
A drip-proof backing 20 made of a relatively hard rubber material is attached around 9.

On the other hand, the terminal blocks 8, 8 have a substantially rectangular parallelepiped shape, and a conductor fixing screw 25 is attached to the upper surface, and a part of the upper surface is cut diagonally to form a mounting surface for the wire fixing screw. Block the thermocouple wire 3 with a screw 8,
It is set to be fixed at 8.

The bushing 36 is used by being inserted over the conductor 16. The bushing 36 is made of a rubber material or the like into a cylindrical shape and has a flange 36a formed on one side. The conductive wire 16 is protected from the screw thread formed on the inner periphery of the insertion portion 12.

To connect the conductor 16 to the terminal box 2 configured as described above, first loosen the fixing screw 15 to open the lid 2b from the terminal box body 2a, and then fix the conductor 16 to the terminal block 8 with the conductor fixing screw 25. .

Next, the conducting wire 16 is inserted into the wiring insertion part 12 through the opening groove 17, and the wiring pipe 14 is screwed into the insertion part 12.

Next, the lid body 2b is closed and the terminal box body 2a and the lid body 2b are fixed together with the fixing screws 15, thereby completing the connection work of the conductive wires 16.

The conductor 16 thus connected is attached to the drip-proof backing 13.2.
Due to the elasticity of the backing 13 and 20, the outer periphery of the conducting wire 16 is in a sealed state without any gaps.

Conductive wire insertion groove 23 in this drip-proof backing 13.20
Since the conductor wire 16 is tapered, it is reliably sealed regardless of the diameter of the conductor wire, and an appropriate pressure is applied to the conductor wire 16.

Furthermore, since the opening groove 17 of the wiring insertion part 12 is made sufficiently smaller in diameter than the diameter of the insertion part 12, the insertion part 12 and the wiring pipe 14 can be securely screwed together even when the lid body 2b is opened. Furthermore, when the lid body 2b is closed, the protruding portion 18 has approximately the same strength as an insertion portion that does not have the opening groove 17.

FIG. 3 is an exploded perspective view showing a method of fixing the protective tube of this invention to a terminal box.

A thermocouple wire 3 is inserted into the protection tube 4 and filled with an inorganic insulating material 30.

A threaded portion 4a is formed at the upper end of the protective tube 4, and a fitting member 4b having a hexagonal nut-like corner portion at a predetermined position to prevent rotation is attached to the protective tube 4 by welding or the like. It is fitted and fixed on the outer periphery.

Also formed in the lower part of the terminal box body 2a is a protective tube holding portion 31 having a temple-shaped inner periphery 31C into which the fitting member 4b of the protective tube 4 is fitted.

Therefore, the fitting member 4b of the protective tube 4 is fitted to the inner circumference 31C of the holding portion 31 and fixed to this holding portion 31, and the nut 32 is attached to the upper end of the protective tube 4 inside the terminal box body 2a. The protective tube 4 is fixed to the holding part 31 of the terminal box 2a by screwing into the threaded part 4a of the terminal box 2a.

Since the fitting member 4b has a corner portion, it can prevent the protection tube 4 from rotating even if the nut 32 is rotated, and the protection tube 4 can be firmly attached to the terminal box through these fitting members. can be fixed to.

Further, as shown in FIG. 4, the fitting member 4b is fixed in advance at a predetermined position relative to the position of the thermocouple wire 3 in the protection tube 4, so that the thermocouple wire 3 , by simply fitting the fitting member 4b into the holding part 31 of the terminal box body 2a, the position of the thermocouple wire 3 can be changed to the predetermined position of the terminal block 8 in the terminal box. The terminal block 8 can be placed at a predetermined position.

Further, the shape of the fitting member 4b may be any shape as long as it can be prevented from rotating, and as shown in FIG. Various shapes are possible, such as a chipped mouth, a rectangular or square corner shape, and an elliptical shape.

As detailed above, this invention forms a threaded part at the upper end of the protective tube into which a detection element such as a thermocouple is inserted, and fixes a fitting member with a non-rotating shape to the terminal box. ,
A holding part is formed that has an inner periphery shaped to fit this fitting member, and the fitting member of the protection tube is fitted into this holding part, and a nut is attached to the threaded part of the protection tube in the terminal box. This is a temperature sensor consisting of a protective tube fixed to a terminal box by screwing it on.

Therefore, by simply fixing a fitting member such as a locking nut to the protective tube by welding, etc., and fitting it to the holding part of the terminal box, it is possible to prevent the protective tube from rotating. It can be firmly fixed to the box.

In addition, by fixing the fitting member to the protective tube so that the detection element is at a predetermined position on the terminal block, and fitting it into the holding part of the terminal box, the detection element can be positioned extremely easily. becomes.

In addition, if an easily available rectangular fitting member such as a hexagonal nut or square is used as a fitting member, it is easy to process and there is no need to prepare special parts, making it inexpensive, easy and reliable. The protection tube can be fixed to prevent it from rotating.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the terminal box according to this invention, Fig. 2 is a perspective view showing the lid in an open state, and Fig. 3 shows a method for fixing the protective tube to the terminal box. Exploded perspective view, 4th
FIG. 5 is an explanatory top view of a protection tube including a terminal block, FIG. 5 is an explanatory view showing various embodiments of the fitting member, and FIG. 6 is an explanatory cross-sectional view showing a conventional example. 2...Terminal box, 2a...Terminal box body,
3... Thermocouple wire as a detection element, 4...
... Protection tube, 31 ... Protection tube holding part, 31
C: Inner periphery of holding portion, 32: Nut, 4a: Threaded portion, 4b: Fitting member.

Claims (1)

[Scope of utility model registration request] 1. In a temperature sensor comprising a protection tube into which a detection element such as a thermocouple is inserted, and a terminal box provided with a terminal for connecting the detection element and an external conductor, the protection tube has a threaded portion at the upper end and is non-rotating. A protective tube holding portion is formed on the terminal box, the inner periphery of which is shaped so that the protective tube fitting member can be fitted into the terminal box, and the protective tube holding portion is fixed to the protective tube. A temperature sensor characterized in that the fitting member of the tube is fitted and the threaded portion of the protective tube is screwed with a nut within the terminal box. 2. The temperature sensor according to claim 1, wherein the fitting member has a rectangular shape.