JPH0727628A - Temperature sensor - Google Patents

Abstract

PURPOSE:To obtain a temperature sensor, wherein the replacement of a thermocouple is simple. CONSTITUTION:The temperature sensor consists of a thermocouple comprising a contact plate 17 and thermocouple lines 16a and 16b, which are extending from both ends of the contact plate, a temperature measuring unit comprising the thermocouple and a heat insulating pipe 19, of which contact plate is located at the upper surface of the temperature measuring unit, and the thermocouple lines are located at the side surface, a casing 10 contains the temperature measuring unit inside under the state, wherein the contact plate is exposed, thermocouple contacts 28 and 29 linked to a signal processing circuit 13 contained in the casing and terminals 26 and 27 of the signal processing circuit, and tapered screws 11 and 12 pushing the thermocouple contacts to the thermocouple lines. The temperature measuring unit can be pulled out by loosening the tapered screws.

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 exposed from a casing is brought into contact with a surface of an object to be measured, and in particular, the temperature is damaged. It is related to the ones that can be easily replaced when you do.

[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 pressed against the object to be measured and thermocouple wires extending from both ends of this contact surface, and a heat insulating member with the contact surface located on the upper surface and the thermocouple wire located on the side surface. The temperature measuring unit is composed of and, and the thermocouple and the signal processing circuit are connected by soldering the extended end of the thermocouple wire to the signal processing circuit, exposing the contact surface of the thermocouple and exposing the temperature measuring unit and the signal. The processing circuit is housed in the casing.

[0003]

Since the temperature sensor of this type has a structure in which the contact surface is directly in pressure contact with the surface of the object to be measured to measure the temperature, the thermocouple is easily damaged. In the above, when the damaged thermocouple is replaced, the thermocouple wire and the signal processing circuit must be re-soldered, so that there is a problem that it takes time and effort.

Therefore, the technical problem of the present invention is to obtain a temperature sensor in which the thermocouple can be easily replaced.

[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, and a temperature measuring unit consisting of a heat insulating member in which the contact surface is located on the upper surface and the thermocouple wire is located on the side surface, and the contact surface is exposed to put the temperature measuring unit inside. A casing for housing, a signal processing circuit housed in the casing, a thermocouple contact connected to the signal processing circuit, and a biasing means for pressing the thermocouple contact to the thermocouple wire, It is characterized by having.

[0006]

The operation of the above technical means is as follows.
Since the thermocouple wire and the signal processing circuit are connected by pressing the thermocouple contact of the signal processing circuit to the thermocouple wire with the urging means, the temperature measuring unit is released by releasing the pressure contact with the urging means. It can be easily attached to and detached from the casing, making it easy to replace a damaged thermocouple.

[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 insulated and coated from the portion of the contact plate 17 facing the lower end of the foot to the portion of the heat insulating tube 19 facing the upper portion of the large diameter portion.

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, the temperature measuring unit can be easily removed from the casing by releasing the pressure contact between the thermocouple wire and the thermocouple contact pressed by the biasing means. Replacing the thermocouple becomes easy.

[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]

 10 casing 11, 12 taper screw 13 signal processing circuit 16a, 16b thermocouple wire 17 contact plate 19 adiabatic pipe 26, 27 terminal 28, 29 thermocouple contact

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 temperature measuring unit including a positioned heat insulating member and a case for housing the temperature measuring unit by exposing the contact surface.
A signal processing circuit housed in the casing, a thermocouple contact connected to the signal processing circuit, and a biasing means for pressing the thermocouple contact to the thermocouple wire. A temperature sensor characterized by.