JPH0727627A - Temperature sensor - Google Patents

Abstract

PURPOSE:To obtain a temperature sensor, wherein a thermocouple is pushed to the surface of an object to be measured with an intended pushing force. CONSTITUTION:A thermocouple comprises a contact plate 17, which is pushed to an object to be measured, and thermocouple lines 16a, 16b, which are extending from both ends of the contact plate. Elastic deformation parts 23a and 23b, which are bent inward beforehand, are formed on the thermocouple lines. A gap 21 is formed between the contact plate and the upper surface of the heat insulating pipe. Windows 20a and 20b, which allow the inward deformation of the elastic deformation parts when the contact plate is pushed down, are formed on the side surface of the heat insulating pipe 19. The contact plate is pushed to the material to be measured with the intended pushing force based on the elastic force of the elastic deformation parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor in which a contact surface of a thermocouple is brought into contact with the surface of an object to be measured to measure the temperature, and in particular, the contact surface is an object to be measured with a desired pressing force. Regarding things that can be pressed against things.

[0002]

2. Description of the Related Art A conventional temperature sensor is disclosed in, for example, Japanese Utility Model Laid-Open No. 3-83829. This is a thermocouple consisting of a contact surface that is pressed against the object to be measured and thermocouple wires that extend from both ends of this contact surface, and a heat insulation tube where the contact surface is located on the upper surface and the thermocouple wire is located on the side surface. And a coil spring that is located outside the thermocouple wire and a coil spring that urges the heat insulating tube upward so that the contact surface projects from the upper surface of the protective tube. By pushing the contact surface to the upper surface of the protective tube, the contact surface can be pressed against the object to be measured with a desired pressing force.

[0003]

The above-mentioned structure requires a coil spring to obtain a desired pressing force, so that the number of parts is increased and the structure is complicated and the cost is increased. was there.

Therefore, a technical object of the present invention is to enable a contact surface of a thermocouple to be pressed against an object to be measured with a desired pressing force without using a coil spring.

[0005]

Means for Solving the Problems The technical means of the present invention taken to solve the above technical problems are a contact surface to be pressed against an object to be measured and a thermoelectric member extended from both ends of the contact surface. A thermocouple consisting of a pair of wires, an adiabatic tube in which the contact surface is located on the upper surface and the thermocouple wire is located on the side surface, and a protective tube located outside the thermocouple wire, the upper surface of the protective tube In the temperature sensor where the contact surface is pushed down to
The thermocouple wire is formed with an elastically deformed portion that is bent inward in advance, and a concave portion that allows the thermocouple wire to be deformed inward when the contact surface is pressed down is formed on the side surface of the heat insulating tube. And a gap is formed between the contact surface of the thermocouple and the upper surface of the heat insulating tube.

[0006]

The operation of the above technical means is as follows.
When the contact surface of the thermocouple is pressed against the object to be measured, the thermocouple is displaced in the direction of the upper surface of the heat insulating tube, and the elastically deformed portion of the thermocouple wire that has been bent inward is further curved inward. Is pushed into the upper surface of the protective tube 23. Therefore, the contact surface is pressed against the object to be measured with a desired pressing force by the elastic reaction force of the elastically deforming portion of the thermocouple wire.

[0007]

EXAMPLES Examples showing specific examples of the present invention will be described (see FIG. 1). In this embodiment, the temperature sensor according to the present invention is combined with a vibration sensor.

A vibration transmitting plate 2 having a female screw is screwed to a vibration detecting needle 1 having a small diameter male screw formed in the lower portion, and the upper face of the vibration transmitting plate 2 is in contact with the lower face of the large diameter portion.
An upper electrode plate 3, a piezoelectric element 4, a lower electrode plate 5, and a weight 6 are sequentially inserted below the vibration transmitting plate 2, and are brought into contact with each other by nuts 7 and fixed to the vibration detecting needle 1. The vibration detecting needle 1 and the vibration transmitting plate 2 are made of stainless steel, the upper and lower electrode plates 3, 5 are made of phosphor bronze, and the weight 6 is made of zirconia ceramic. The vibration detecting needle 1, the vibration transmitting plate 2, the upper electrode plate 3, the piezoelectric element 4, the electrode plate 5, and the weight 6 form a vibration detecting unit of a vibration sensor.

In the vibration detecting unit, the upper surface of the vibration transmitting plate 2 and the lower surface of the weight 6 are provided with a cutout from the front side to the opposite side, and a bifurcated part extending downward from the end on the opposite side of the upper wall toward the front side. It is held by being sandwiched by a switch fitting 9 composed of the spring part of the switch fitting 9 and is urged upward by the spring part of the switch fitting 9 so that the upper surface of the vibration transmitting plate 2 is brought into contact with the lower surface of the upper wall of the switch fitting 9. ing. Further, the switch fitting 9 has two side walls extending downward from the upper wall, and the side wall and the upper wall are held by the inner wall of the casing 10, so that the vibration detection unit can be casing. 1
It is attached to 0.

The casing 10 is formed of two casing members on the front side opposite to the paper surface, and the taper screw 1
1, 12 are connected. The switch fitting 9 is made of stainless steel, and the casing 10 is made of PEEK. Conductive wires (not shown) from the upper and lower electrode plates 3 and 5 are connected to terminals 14 and 15 of the signal processing circuit 13.

The thermocouple wires 16a and 16b, which are made of long thin plates of chromel and alumel, are bent inward at their upper ends, and have a disk shape having a hole at the center above and below the bent parts and extend downward to the periphery. A contact plate 17 having one foot and a disc-shaped protection plate 18 having a hole in the center are fixed by welding. A thermocouple is formed from the thermocouple wires 16a and 16b, the contact plate 17, and the protective plate 18.

The hollow cylindrical heat insulating tube 19 located inside the thermocouple is composed of a small diameter portion in the upper part, a large diameter portion in the lower portion and a long intermediate diameter portion in the middle, and the upper and lower ends are left in the medium diameter portion. Thus, two windows 20a, 20b having a width substantially equal to the diameter of the hollow portion and communicating with each other through the hollow portion are formed on both sides.
The remaining portions on the upper side of b are cut vertically, and the remaining portions on the lower side of both windows 20a and 20b are cut inward toward the top.

In the thermocouple, the protective plate 18 has a slight gap 21 between the lower surface thereof and the upper surface of the heat insulating tube 19, and the thermocouple wires 16a and 16b extend from the outside of the small diameter portion of the heat insulating tube 19 into the window. It is wound from the outside of the large diameter portion through the lower surface into the large diameter hole and is fixed by the ring 22 press-fitted into the large diameter hole. The portions of the thermocouple wires 16a and 16b located inside the windows are elastically deformed portions 23a and 23b that are bent inward in advance, respectively.
Is formed as the contact plate 17 is pushed down,
It can be further elastically deformed inward as long as it does not come into contact with the inner vibration detecting needle 1.

Outside the small-diameter portion and the medium-diameter portion of the heat insulating pipe 19, the protective pipe 2 has an inner diameter slightly larger than the outer diameter of the medium-diameter portion.
4 has been inserted. The protection tube 24 is fitted to a protrusion 25 shown by a dotted line formed at the lower end of the side surface of the heat insulating tube 19 at the middle diameter portion, and is prevented from being pulled out. The thermocouple, the heat insulating tube 19, the ring 22, and the protective tube 24 form a temperature measuring unit of a temperature sensor. Contact plate 17, protection plate 18, and protection tube 23
Is made of stainless steel, the heat insulating tube is made of PEEK, and the ring 22 is made of Bakelite. The thermocouple wires 16a and 16b are insulation-coated from a portion facing the lower end of the foot of the contact plate 17 to a portion facing the upper part of the large diameter portion of the heat insulating pipe 19.

The temperature measuring unit is passed through the vibration detecting needle 1 and inserted through the upper end opening of the casing 10. The portions of the thermocouple wires 16a and 16b located outside the large diameter portion of the heat insulating pipe 19 are connected to the thermocouple contacts 28 and 29 connected to the terminals 26 and 27 of the signal processing circuit 13 to be connected. Taper
Vertical cuts are provided around the screw holes of the casing 10 corresponding to the screws 11 and 12, respectively.
The inner portions 30, 31 of the respective slits are deformed inward by screwing 1, 12 therein. As a result, the thermocouple wires 16a and 16b and the thermocouple contacts 28 and 29 are firmly pressed against each other, and the temperature measuring unit is casing 1.
It is fixed at 0. The taper screws 11 and 12 constitute a biasing means, and the temperature measuring unit can be pulled out from the casing 10 by loosening the taper screws 11 and 12.

When measuring the operating state of the object to be measured,
Holding the casing 10 by hand, the tip of the vibration detecting needle 1 is pressed against the surface of the object to be measured, and pushed to the upper surface of the contact plate 17 of the thermocouple against the elastic force of the spring portion of the switch fitting 9. As a result, the contact plate 17 of the thermocouple is also pressed against the object to be measured. Further, the elastically deforming portions 23a and 23b of the thermocouple wires 16a and 16b are deformed inward, and the tip of the vibration detecting needle 1 and the upper surface of the contact plate 17 are pushed to the upper surface of the protective tube 24.

Mechanical vibration of the object to be measured causes vibration detection needle 1.
Through the vibration transmission plate 2 and acts on the piezoelectric element 4 as a pressure fluctuation. In response to this, a voltage change occurs in the piezoelectric element 4. This voltage fluctuation is sent from the electrode plates 3 and 5 to the terminals 14 and 15 of the signal processing circuit 13 through the conductors, amplified and detected by the signal processing circuit 13, and calculated into an average value or a peak value. , Is displayed on the display unit (not shown). On the other hand, the temperature signal of the object to be measured is detected by the thermocouple wires 16a and 16b via the contact plate 17, and the thermocouple contact 28,
It is sent to the terminals 26 and 27 of the signal processing circuit 13 via 29, amplified, and displayed on the display unit.

[0018]

The present invention produces the following unique effects. As described above, according to the present invention, since the contact surface of the thermocouple is pressed against the object to be measured with a desired pressing force by the elastic force of the elastic deformation portion formed on the thermocouple wire, the number of parts is small. The structure is simple. When the elastically deforming portion of the thermocouple wire is bent outward, the diameter of the protection tube must be increased, but in the present invention, since it is bent inward, it is not necessary to increase the diameter of the protection tube, and the shape is compact.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a vibration sensor with a temperature sensor in which a temperature sensor according to an embodiment of the present invention is combined with a vibration sensor.

[Explanation of symbols]

 16a, 16b Thermocouple wire 17 Contact plate 19 Adiabatic tube 20a, 20b Window 21 Gap 23a, 23b Elastic deformation part 24 Protective tube

Claims (1)

[Claims] 1. A thermocouple comprising a contact surface pressed against an object to be measured and thermocouple wires extending from both ends of the contact surface, the contact surface being located on an upper surface, and the thermocouple wire being located on a side surface. A heat-insulating tube positioned and a protective tube located outside the thermocouple wire, in which the contact surface is pushed down to the upper surface of the protective tube, the elastically deformable portion being bent inward to the thermocouple wire in advance. And forming a concave portion on the side surface of the heat insulating pipe that allows the elastic deformation portion of the thermocouple wire to be deformed inward when the contact surface is pushed down, and the contact surface of the thermocouple and the heat insulating pipe are formed. A temperature sensor characterized in that a gap is formed between the upper surface of the temperature sensor and the upper surface of the temperature sensor.