JP3073944B2 - Flat sheet interface sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat sheet-like interface sensor which is immersed in a fluid and detects the immersion state, and more particularly to the immersion state on the surface of the buried portion which the fluid should closely cover. The present invention relates to a flat sheet-like interface sensor that can be detected.

[0002]

2. Description of the Related Art FIG. 5 is a perspective view showing a use state of a conventional interface sensor. The interface sensor 101 is used to detect the state of immersion of a fluid, for example, when grasping the state of concrete being poured. This interface sensor 101 is conventionally
It is constituted by a thermocouple, an open electrode, and the like, and can detect the arrival of the fluid based on the temperature and electric conductivity of the fluid. By arranging the interface sensor 101 in a filling section such as a reinforcing bar 102, In addition, it is possible to detect the state of immersion of the fluid in the details of the construction part. In particular, the filling end, which is difficult to fill, such as the molding upper frame that closes the top of the concrete casting part or the lower part of the buried part of the buried member, is used to avoid insufficient filling and ensure the construction quality. It is necessary to arrange a sensor and grasp the immersion situation.

[0003]

However, when the buried portion 102 is a metal member, such as reinforced concrete or concrete casting using a metal form, the fluid is affected by the electric and heat conduction by the metal member. Since it is difficult to detect the sensor 103, it is necessary to dispose the sensor detector 104 at a position separated from the surface of the buried part 102 by a certain dimension H in order to eliminate the influence of such a metal member. The state of immersion on the surface of the buried portion 102 to be covered with the fluid in close contact cannot be detected.

An object of the present invention is to solve the above-mentioned problems by providing a flat sheet-like interface sensor capable of accurately detecting the state of immersion on the surface of an embedded portion immersed in a fluid. is there.

[0005]

According to a first aspect of the present invention, a first contact portion and a second contact portion of a thermocouple are formed on an insulating sheet which forms a sheet-like insulating substrate and are separated from each other. And a heater for heating the second contact portion is formed on an insulating sheet, and the first contact portion is provided at a location not receiving heat from the heater. , The second contact portion and the heater are covered with an insulating protective member.

This sensor heats the second contact portion by energizing the heater. If there is no convection factor in the fluid, the heated heat is radiated to the fluid according to a radiation coefficient (mainly, thermal conductivity, specific heat, specific gravity) between the fluid and the sensor. The second contact is a first contact (compensation contact) that is spaced apart from the heater without being affected by heat.
And the differential circuit, the immersion state can be detected by the output difference due to the radiation coefficient regardless of the temperature of the fluid. Therefore, the first contact is provided apart from the heater so as not to be affected by the heat of the heater, so that the temperature of the fluid can be always measured, and by using it as an argument of the differential circuit, the first contact can be used for measuring the radiation coefficient. It becomes a temperature compensation contact.

According to a second aspect of the invention, in addition to the configuration of the first aspect, the first contact portion and the second contact portion are each formed in a thin film, and the heater is formed in a thin film. The insulating sheet, the first and second contact portions, the heater and the ends of these lead wires are covered with an insulating protective member, and the whole is integrally formed in a flexible thin plate shape. A completely waterproof flat sheet-like interface sensor that forms the body was used.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect of the present invention, a thermocouple composed of the first contact portion and the second contact portion is provided in multiple stages. The differential circuits are formed in series to form a differential circuit, and a heater for heating each of the multi-stage second contact portions is formed on an insulating substrate.
The contact portions are formed so as not to receive the heat of the heater and to be close to positions where they have the same temperature.
Each of the second contact portions is a flat sheet-like sensor formed close to each other so as to have the same temperature, and high-sensitivity detection can be performed by increasing the output in accordance with the number of thermocouple sets. It becomes possible.

Further, the invention of claim 4 provides the above-mentioned claim 1.
Item 2 In addition to the structure of any one of the inventions of Item 2, a flat sheet-like interface sensor comprising an attachment portion made of an adhesive or the like on one surface of the protective member, and the attachment portion makes it easier. Can be attached to the measurement site.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of the flat sheet-like interface sensor according to the present invention, which is partially broken. The flat sheet-shaped interface sensor 1 is formed by alternately connecting contact members 3 and 4 of a thermocouple on an insulating sheet 2 forming a sheet-shaped insulating substrate to form a thin film. These contact members 3, 4
Forms a first contact portion 5 with the contact member 3 at the end and the contact member 4 connected thereto, and a second contact portion 6 between the contact member 4 and the contact member 3 to be connected next. To form
A pair of differential thermocouple circuits is formed by these adjacent contact portions 5 and 6, and a thermocouple connected in series in multiple stages is formed by using the differential thermocouple circuit as a constituent unit.

The first contact portions 5 and the second contact portions 6.
Are formed apart from each other, and the first contact portions 5 are close to each other so as to have the same temperature.
The second contact portions 6 are also formed close to each other so as to have the same temperature, and a heater 7 for heating the second contact portions 6 is formed on the lower surface side of the insulating sheet 2 in a thin film shape. The heater 7 is formed of a constantan foil or the like, and leads out lead wires 7a.

The specific configuration of each of the contact portions 5 and 6 is such that a copper foil portion and a constantan foil forming the contact members 3 and 4 formed in contact with each other on the insulating sheet 2 are formed by etching, and the compensating end is formed. Leads 8 and 9 are led out from the ends of the two contact members 3 and 4 forming the first contact portion 5 on the side, and lead 10 is led out from the contact member 3 made of copper foil at the end.

FIG. 2 is a sectional view taken along line XX of FIG. First
And the second contact portions 6, the insulating sheet 2, and the thin-film heater 7 are provided with an insulating protection comprising a covering member 11 such as Teflon FEP and a sheet-like outer covering member 12 made of polyimide resin or the like. The member is heated and pressurized from both sides, and is integrally formed, including the FEP coating of the lead portion 1a, to form a thin, sheet-like, completely waterproof, integrally molded body. One side is provided with a mounting portion 13 made of an adhesive having a small thermal conductivity and release paper.

The operation of the flat sheet-like interface sensor having the above configuration will be described below. Since the first contact portion 5 including the lead wires 8 and 9 is disposed away from the heater 7 so as not to be affected by heat from the heater,
A differential circuit may be configured with the second contact to act as a temperature compensating contact for the output of the radiation coefficient, and the temperature of the fluid may be used as a sensor of a thermocouple thermometer.

The second contact portion 6 forms a high-temperature contact with the first contact portions 5 by applying a constant current to the heater 7 and heating the heater. Accordingly, a serial output of a thermocouple corresponding to the temperature difference between the first contact portion 5 and the second contact portion 6 can be obtained from the lead wires 8 and 10 at both ends, and the flat sheet-like interface sensor 1 flows. If there is no convection factor of the fluid when immersed in the body, the temperature difference changes according to the radiation coefficient, and it can be detected as a change in the serial output of the difference of the differential circuit. This serial output enables high-sensitivity detection by increasing the output in accordance with the number of series thermocouples.
Due to this increase in sensitivity, it is possible to suppress a rise in temperature of the high-temperature side contact and to suppress heater power.

As described above, in the flat sheet-like interface sensor according to the present invention, the thermocouple is insulated by the protective member, forms a flexible, thin, water-proof, integral molded body, and has a mounting portion on one side. Because of the formation, the fluid can be attached and adhered easily along the surface of the buried part that should be covered by the fluid, and the immersion state of the surface of the buried part can be detected. Including the same case, for the interface between media having large heat dissipation coefficients (mainly specific heat, specific gravity, thermal conductivity) such as concrete and air, regardless of the material type of the buried part, Can be detected.

The flat sheet-shaped interface sensor 1 can form the contact portions 5, 6 and the heater 7 at low cost and with high precision by etching, and has a large response area due to a large heat transfer area and a small heat capacity. Can be secured.

FIG. 3 is a diagram showing a use state of the flat sheet-like interface sensor of FIG. Figure (A) shows concrete A
The flat sheet-shaped interface sensor 1 is adhered to a lower surface 21a of a buried portion of a metal pipe 21 buried therein. FIG.
The flat sheet-like interface sensor 1 is adhered to 2a. Fig. (C) shows a reinforcing bar 2 embedded in concrete A.
3, a flat sheet-like interface sensor 1 is attached to the side surface 23a. The flat sheet-like interface sensor 1 can detect the immersion state of the concrete A at the top of the filling defined by the metal member and the immersion state of the concrete A at the surface of the buried portion of the metal member.

The flat sheet-like interface sensor is used to measure the temperature after casting concrete for the purpose of analyzing the thermal stress due to the heat of hydration during hardening of ready-mixed concrete, and to measure the liquid level without asking the type or temperature of the fluid. Not only can it be used as, but also determine the type of fluid based on the relationship between the amount of heat supplied by the heater and the radiation coefficient caused by the radiation coefficient of the fluid (mainly specific heat, specific gravity, thermal conductivity) Can be.
In addition, as shown in FIG. 4, two flat sheet-like interface sensors 1 of a high order and a low order are arranged, a differential circuit is provided, and based on an output difference between both the sensors 1 and 1 ', an underwater concrete placement level is set. It is also possible to detect an interface between media having a small difference in specific gravity, specific heat, and thermal conductivity, as in the detection of an object.

[0020]

In the flat sheet-like interface sensor according to the first aspect of the present invention, when the heater is energized, the temperature of the second contact portion rises, and the temperature difference between these two contact portions has no convection factor. For example, the immersion state can be detected irrespective of the temperature of the fluid because the sensor and the fluid undergo changes depending on the difference in heat radiation coefficient. Further, since the first contact portion is disposed apart from the heater so as not to be affected by the heat of the heater, the temperature of the fluid can be constantly measured.

According to a second aspect of the present invention, in addition to the effects of the first aspect of the present invention, a flat sheet-like interface sensor is provided by mounting first and second contact portions of a thermocouple and a heater on an insulating sheet. Formed in a thin film form, and a thin, completely waterproof, integral molded body composed of insulating protection members including the ends of these lead wires is formed. Since the sensor can be attached to the buried portion, the immersion state of the buried portion surface can be accurately detected. Also, since it is completely waterproof, it can be used for a long time.

According to a third aspect of the present invention, in addition to the effects of the second aspect of the present invention, the number of sets of thermocouples is increased by using a flat sheet, and the output is increased by increasing the heat radiation surface area. , High-sensitivity detection becomes possible. Due to this increase in sensitivity, it is possible to suppress a rise in temperature of the high-temperature side contact and to suppress heater power.

According to a fourth aspect of the present invention, in addition to the effects of the first and second aspects of the present invention, the protective member is provided with a mounting portion such as an adhesive on one surface, so that the protection member can be mounted on the measurement site very easily. it can.

[Brief description of the drawings]

FIG. 1 is a partially broken plan view of a flat sheet-like interface sensor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIGS. 3A, 3B, and 3C are perspective views showing states of use of the flat sheet-like interface sensor according to the embodiment of the present invention; FIG.

FIG. 4 is a perspective view showing another usage state of the flat sheet-like interface sensor according to the embodiment of the present invention.

FIG. 5 is a perspective view showing a use state of a conventional interface sensor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Flat sheet-like interface sensor 1a Lead part 2 Insulating sheet 3 Contact member 4 Contact member 5 First contact part 6 Second contact part 7 Heater 11 Covering member 12 Skin member 13 Mounting part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01F 23/22 G01K ⁷ /02-7/14

Claims (4)

(57) [Claims] 1. A first contact portion and a second contact portion of a thermocouple are formed on an insulating sheet forming a sheet-like insulating substrate apart from each other, and the second contact portion is heated. The first contact portion is provided at a location where the heater does not receive heat, and the insulating sheet, the first and second contact portions, and the heater are insulated from each other. A flat sheet-like interface sensor covered by the protective member of (1). 2. A thermocouple comprising a first contact portion and a second contact portion which are formed in a thin film form on an insulating sheet forming a sheet-like insulating base and separated from each other. A heater for heating the contact portion is formed in a thin film on an insulating sheet, and the first contact portion is provided at a location not receiving heat from the heater, and the insulating sheet, the first and second contacts are provided. A flat type, wherein the entire section, the heater, and the ends of these lead wires are covered with an insulating protective member, and the whole is formed as a flexible thin plate-shaped integrally formed body, and is a completely waterproof type. Sheet-shaped interface sensor. 3. A thermocouple composed of the first contact portion and the second contact portion is formed by connecting the thermocouples in series in multiple stages, and each of the multistage second contact portions is heated. A heater is formed on an insulating base, and the first contact portions are formed so as not to receive the heat of the heater and to be close to positions where they have the same temperature as each other. 3. The flat sheet-shaped sensor according to claim 1, wherein the contact portions are formed close to each other so as to have the same temperature. 4. The protection member according to claim 1, further comprising an attachment portion formed on one surface of the protection member by an adhesive or the like having a small heat conductivity. Flat sheet sensor.