WO2010113477A1 - Sensor having cover and method for manufacturing the sensor - Google Patents

Abstract

Provided is a sensor having a cover, which is provided at least with: a base section (3) which holds two or more electrode pins (2a, 2b); a sensor element (4) connected to the electrode pins (2a, 2b); and a sensor cover (5) which covers the sensor element (4) by being assembled to the base section (3) and has a predetermined ventilation characteristics. On the surface of at least a part of the base section (3), including the electrode pins (2a, 2b), and/or on the surface of at least a part of the sensor cover (5), a weather-resistant and water-repellent film (6t), which is composed of a weather-resistant and water repellent material (Rt) using a silicone resin containing a transition metal compound and has a predetermined thickness (Dt), is formed.

Description

Sensor with cover and method for manufacturing the same

The present invention relates to a sensor with a cover including a base part that holds an electrode pin to which a sensor element is connected, a sensor cover that is used by being assembled to the base part, and a method for manufacturing the same.

In general, as disclosed in Patent Document 1, a gas sensor that detects gas leakage and the like, and a sensor element that reacts to the presence of gas, mechanically protects the sensor element, and uses unnecessary foreign substances other than gas. A sensor cover having a dust removal function for preventing intrusion is provided. The sensor cover is required to ensure a predetermined gas permeability and to have a required dust removal function.

Therefore, normally, porous ceramics that can meet the demands of both gas permeability and dust removal function are used for this type of sensor cover. A sensor cover for bulk porous ceramics that allows detection to function simultaneously is disclosed.

On the other hand, since this type of gas sensor is covered with a sensor cover having a predetermined gas permeability, there is a problem that the inside of the sensor cover is likely to be condensed. When condensation occurs, the sensor elements placed inside the sensor cover and the electrical system circuits such as the electrode pins that connect the sensor elements are adversely affected. For example, zero point fluctuation, temporary decrease in sensor sensitivity, There is a concern that a short circuit or the like may be caused, and in particular, since the electrode pin is provided so as to penetrate inside and outside of the base portion, there is a concern that when the water droplets adhere to the base portion, a short circuit between the electrode pins may be caused. .

For this reason, Patent Document 2 also discloses a gas sensor having a dew condensation prevention function in which the gas detection unit and the inflowing test gas are heated by the heating element unit to prevent dew condensation.

Furthermore, the inventors of the present invention provide an inexpensive and easy-to-produce silicone resin water-repellent film on the base, electrode pins, and porous ceramic sensor cover as disclosed in Patent Document 3, in contrast to the gas sensor described above. Has proposed.

Next, a gas water heater, which is an example of a device for installing a gas sensor, will be described. Conventional hot water heaters have a structure in which hot water is discharged through a primary heat exchanger, but recently, a type called a latent heat recovery type in which a secondary heat exchanger is provided after the primary heat exchanger has come out. It is coming. The purpose is to improve the heat exchange efficiency and the exhaust loss is improved from about 20% to about 5% of the conventional type. However, the drain water discharged from the heat exchanger is more in the latent heat recovery type. Become. Moreover, since this drain water becomes acidic by the component contained in exhaust gas, it has a structure where it neutralizes through the neutralizer and is discharged out of the water heater.

JP 2002-243684 A JP 2003-161712 A JP 2008-83008 A

However, the conventional sensor with a cover described above has the following problems. For example, in the case of the gas sensor used by being attached to the above-described hot water heater, the exhaust gas temperature at the position where the gas sensor is attached is about 300 ° C. in the conventional type, and about 80 ° C. in the latent heat recovery type. In addition to water vapor, the exhaust gas component includes CO ₂ , N ₂ , O ₂ , NO _x , and SO _x , and the NO _x and SO _x make the drain water acidic, depending on the situation. In some cases, you may land. Therefore, the conventional water-repellent structure is insufficient in at least heat resistance and acid resistance, and causes problems that cannot be ignored such as failure during use, and it is difficult to ensure sufficient durability and reliability. .

An object of the present invention is to provide a sensor with a cover that solves the problems existing in the background art and a manufacturing method thereof.

In order to solve the above-described problem, the cover-equipped sensor 1 according to the present invention includes at least a base portion 3 that holds two or more electrode pins 2a and 2b, a sensor element 4 that is connected to the electrode pins 2a and 2b, and a base When configuring a sensor with a cover including a sensor cover 5 having a predetermined air permeability that covers the sensor element 4 by being assembled to the part 3, at least a part of the surface of the base part 3 including the electrode pins 2a and 2b, the sensor cover A weather-resistant water-repellent film 6t having a predetermined film thickness Dt made of a weather-resistant water-repellent material Rt using a silicone resin containing a transition metal compound is formed on one or both of at least a part of the surface 5 It is characterized by.

In this case, according to a preferred embodiment of the invention, a silicone resin can be used as the silicone resin, and niobium pentoxide (Nb ₂ O ₅ ) can be used as the transition metal compound. The film thickness Dt of the weather-resistant water-repellent film 6t is selected in the range of 0.3 to 1.0 [μm], and the water contact angle is 90 ° or more as a water repellency evaluation value. It is desirable to select a property of 50% or more. The cover-equipped sensor 1 is suitable for a gas sensor having a porous cover 5s. On the other hand, on the weather-resistant water-repellent film 6t, there is at least one layer using a weather-resistant water-repellent material Rc different from the weather-resistant water-repellent film 6t, and the weather-resistant surface repellent having a predetermined film thickness Dc. It is desirable to form the water film 6c. PTFE (polytetrafluoroethylene) can be used as the weather-resistant water-repellent material Rc forming the weather-resistant surface water-repellent film 6c, and the weather-resistant surface water-repellent film 6c can be formed as a sintered film.

On the other hand, in order to solve the above-described problem, the method for manufacturing the sensor with cover 1 according to the present invention includes at least a base portion 3 that holds two or more electrode pins 2a and 2b and a sensor connected to the electrode pins 2a and 2b. When manufacturing the sensor with cover 1 including the element 4 and the sensor cover 5 having a predetermined air permeability that covers the sensor element 4 by being assembled to the base portion 3, at least one of the base portions 3 including the electrode pins 2a and 2b. Weather resistant water repellent having a predetermined film thickness Dt of a weather resistant water repellent material Rt using a silicone resin containing a transition metal compound on one or both of the surface of the sensor and at least a part of the surface of the sensor cover 5 A water repellent film forming step P for forming the film 6t is included.

In this case, according to a preferred aspect of the invention, the water repellent film forming step P includes at least a part of the surface of the pin assembly 7 in which the electrode pins 2a and 2b and the part 3p of the base part 3 are assembled. The pin-side water-repellent film forming step Pp for forming the water film Dt, and the weather-resistant water-repellent film 6t is formed on at least a part of the surface of the base cover assembly 8 in which the remaining part 3r of the base part 3 and the sensor cover 5 are assembled. And a cover-side water-repellent film forming step Pc. Further, in the pin-side water-repellent film forming step Pp, the pin-side water-repellent film attaching step Ppx includes an immersion process in which the pin assembly 7 is immersed in a water-repellent treatment liquid using the weather-resistant water-repellent material Rt for a predetermined time. And after the pin-side water-repellent film attaching step Ppx, the pin-side water-repellent film firing step Ppy for heating and firing at a predetermined temperature and time after the pin assembly 7 to which the water-repellent treatment liquid is attached is dried at room temperature. In addition, the cover-side water-repellent film forming step Pc includes a dipping process in which the base cover assembly 8 is dipped in a water-repellent treatment liquid using the weather-resistant water-repellent material Rc for a predetermined time. After the cover-side water-repellent film attaching step Pcx and the cover-side water-repellent film attaching step Pcx are finished, the base cover assembly 8 to which the water-repellent treatment liquid is attached is dried at room temperature and then at a predetermined temperature and time. Makes it possible to include a cover-side water-repellent film firing step Pcy of firing. On the other hand, a silicone resin can be used for the silicone resin, and niobium pentoxide can be used for the transition metal compound. The film thickness Dt of the weather-resistant water repellent film Rt is selected in the range of 0.3 to 1.0 [μm], and the water contact angle is 90 ° or more as a water repellency evaluation value, and a predetermined air permeability is provided. It is desirable to select 50% or more.

Further, after completion of the water repellent film forming step P, the weather resistant water repellent film 6t has at least one or more layers using a weather resistant water repellent material Rc different from the weather resistant water repellent film 6t, and has a predetermined A surface water-repellent film forming step Q for forming the weather-resistant surface water-repellent film 6c having the film thickness Dc can be provided. PTFE can be used for the weather-resistant water-repellent material Rc that forms the weather-resistant surface water-repellent film 6c. In the surface water-repellent film forming step Q, the pin assembly 7 obtained in the pin-side water-repellent film forming step Pp is used as the water-repellent material using the weather-resistant water-repellent material Rc for forming the weather-resistant surface water-repellent film 6c. A pin-side surface water-repellent film adhering step Qpx including a dipping process for immersing in a treating liquid for a predetermined time, and after the pin-side surface water-repellent film adhering step Qpx is finished, a pin assembly 7 to which the water-repellent treating liquid is adhered is The pin-side surface water-repellent film firing step Qpy that is heated and fired at a predetermined temperature and time after drying at room temperature can be included, and the base cover assembly 8 obtained in the cover-side water-repellent film forming step Pc can be weathered. Cover-side surface water-repellent film adhering step Qcx including a dipping process of immersing in a water-repellent treatment liquid using the weather-resistant water-repellent material Rc for forming the water-repellent surface water-repellent film 6c for a predetermined time; Film adhesion process After completion of the cx, it can be included and the cover surface water-repellent film firing step Qcy of firing by a predetermined temperature and for a time after the base cover assembly 8 in which the water-repellent liquid is adhered and dried at room temperature. At this time, 320 ° C. to 420 ° C. can be set as the predetermined temperature for heating and baking.

The cover-equipped sensor 1 according to the present invention and the manufacturing method thereof have the following remarkable effects.

(1) In the sensor with cover 1 of the present invention, a transition metal compound is contained in one or both of at least part of the surface of the base part 3 including the electrode pins 2a and 2b and at least part of the surface of the sensor cover 5. Since the weather-resistant water-repellent film 6t having a predetermined film thickness Dt is formed by the weather-resistant water-repellent material Rt using the silicone-based resin, moisture permeation into the sensor cover 5 can be effectively prevented, Even under the environment where the acidic drain water is struck, it is possible to protect the part disposed on the inside, and it is difficult for dust to enter, clogging, and further, the gas permeability is lowered. In addition to the basic function and effect of the water-repellent film that can prevent (deterioration) and maintain detection accuracy and ensure reliability, the basic function of the water-repellent film is achieved by adding high weather resistance. With the result can be maintained for a long time, it can ensure excellent heat resistance, acid resistance and durability.

(2) In the cover-equipped sensor 1 of the present invention, in particular, if water repellent treatment is applied to the pin assembly 7 and the base cover assembly 8, a synergistic effect based on both water repellent treatments, that is, to the outside of the sensor cover 5 Is the first water-repellent effect that prevents the intrusion of unnecessary moisture, and the water-repellent effect applied to the surface of the pin assembly 7 even if moisture enters the inside of the sensor cover 5 and causes condensation. Obtaining a sensor 1 with a cover that can enjoy a synergistic effect due to the second water repellent effect that prevents a short circuit between the electrode pins 2a and 2b based on the film, and is strong against both moisture caused by the internal environment and moisture caused by the external environment. These synergistic effects can be maintained over a long period of time by adding high weather resistance in addition to being able to perform, and is optimal for use in gas sensors and the like.

(3) In the cover-equipped sensor 1 of the present invention, according to a preferred embodiment, when a silicone resin is used as the silicone resin and niobium pentoxide is used as the transition metal compound, the heat resistance of the water-repellent film, Acid resistance and durability can be further increased.

(4) The sensor with cover 1 of the present invention has at least one or more layers using a weather-resistant water-repellent material Rc different from the weather-resistant water-repellent film 6t on the weather-resistant water-repellent film 6t, and has a predetermined If the weather-resistant surface water-repellent film 6c having the film thickness Dc is formed, in particular, the inner weather-resistant water-repellent film 6t can further improve the fixing property and heat resistance to the surface of the sensor cover 5, etc. The outer weather-resistant surface water-repellent film 6c can further improve acid resistance and water vapor resistance. Therefore, it is possible to maintain a more reliable water repellency performance in terms of weather resistance than before, and a water repellency structure that can maintain water repellency performance even when used in an exhaust gas environment such as a gas water heater. be able to.

(5) In the cover-equipped sensor 1 of the present invention, if the weather-resistant surface water-repellent film 6c is formed of a sintered film using PTFE according to a preferred embodiment, in particular, the water-repellent film has heat resistance, acid resistance and durability. Sex can be further enhanced.

(6) In the method for manufacturing a sensor with a cover according to the present invention, a transition metal compound is provided on one or both of at least a part of the surface of the base 3 including the electrode pins 2a and 2b and at least a part of the surface of the sensor cover 5. Since the water-repellent film forming step P for forming the weather-resistant water-repellent film 6t having a predetermined film thickness Dt by the weather-resistant water-repellent material Rt using the silicone-based resin containing the resin is included, The attached sensor 1 can be easily manufactured.

(7) In the method for manufacturing a sensor with a cover according to the present invention, according to a preferred embodiment, the pin assembly 7 is applied to the water-repellent treatment liquid using the weather-resistant water-repellent material Rt in the pin-side water-repellent film forming step Pp. After the pin-side water-repellent film adhering step Ppx including the dipping process for dipping for a period of time, and after the pin-side water-repellent film adhering step Ppx is finished, the pin assembly 7 to which the water-repellent treatment liquid is adhered is dried at room temperature and then given temperature. And a pin-side water-repellent film firing step Ppy that is heated and fired according to time, and the base-side assembly 8 is applied to the water-repellent treatment liquid using the weather-resistant water-repellent material Rc in the cover-side water-repellent film forming step Pc. Cover-side water-repellent film adhesion step Pcx including an immersion process for immersing for a predetermined time, and base cover assembly 8 to which the water-repellent treatment liquid has adhered after completion of this cover-side water-repellent film adhesion step Pcx. If the cover-side water-repellent film firing step Pcy is performed that is heated and fired at a predetermined temperature and time after drying at room temperature, the weather-resistant water-repellent film 6t having a predetermined film thickness Dt is formed by the weather-resistant water-repellent material Rt. At this time, the necessary weather-resistant water-repellent film 6t can be efficiently and inexpensively formed at the necessary site.

The perspective view which shows the internal structure of the sensor with a cover which concerns on 1st embodiment of this invention by a cross section, Cross-sectional front view of the sensor with the cover, Cross-sectional front view of pin assembly used for sensor with cover, The process figure which shows the pin side water-repellent film formation process of the pin assembly in the manufacturing method of the sensor with the cover, A process diagram showing a cover-side water-repellent film forming process and an assembling process of the base cover assembly in the manufacturing method of the sensor with the cover, Explanatory drawing of the pin side water-repellent film forming process of the pin assembly in the manufacturing method of the sensor with the cover, Explanatory drawing of the cover side water-repellent film formation process of the base cover assembly in the manufacturing method of the sensor with the cover, Explanatory drawing of the assembly process in the manufacturing method of the sensor with the cover, A schematic cross-sectional view showing a water-repellent film forming part of the sensor with the cover, A characteristic diagram showing the results of a heat and durability water repellency test for the sensor with the cover, The characteristic view which shows the acid-resistant durable water-repellent test result by the water-repellent film drying conditions in the manufacturing method of the sensor with the cover, Characteristic diagram showing gas permeability and water repellency test results for the amount of niobium pentoxide added to the sensor with the cover, The characteristic view which shows the water repellency test result by the heating temperature at the time of drying in the manufacturing method of the sensor with the cover, The characteristic view which shows the water repellency test result by the heating temperature keep time at the time of drying in the manufacturing method of the sensor with the cover, A photograph showing the state of the water-repellent film after heat drying (200 ° C., 1 H) in the manufacturing method of the sensor with cover, A photograph showing the state of the water-repellent film after heat treatment (200 ° C., 1H + 400 ° C., 1H) in the manufacturing method of the sensor with cover; The perspective view which shows the internal structure of the sensor with a cover which concerns on 2nd embodiment of this invention by a cross section, Cross-sectional front view of pin assembly used for sensor with cover, A schematic cross-sectional view showing a water-repellent film forming part of the sensor with the cover, Process drawing which shows the pin side water-repellent film formation process and pin side surface water-repellent film formation process of the pin assembly in the manufacturing method of the sensor with the cover, A cover-side water-repellent film forming step, a cover-side surface water-repellent film forming step and an assembling step of the cover base assembly in the manufacturing method of the sensor with cover; The graph which shows the result of having performed the water-repellent performance test of the sensor with the cover after exposure in a 400 ° C environment, A graph showing the results of a water-repellent performance test after exposure of the sensor with the cover in a gas water heater exhaust gas environment, SEM photo of weather-resistant water repellent film of the sensor with the same cover, SEM photograph of weather-resistant surface water-repellent film of the sensor with the same cover,

DESCRIPTION OF SYMBOLS 1: Sensor with cover, 2a: Electrode pin, 2b: Electrode pin, 3: Base part, 4: Sensor element, 5: Sensor cover, 5s: Porous cover, 6t: Weather-resistant water-repellent film, 6c: Weather-resistant surface Water repellent film, 7: Pin assembly, 8: Base cover assembly, Rt: Weather resistant water repellent material, Rc: Weather resistant water repellent material, Dt: Film thickness, Dc: Film thickness, P: Water repellent film forming process, Pp : Pin side water repellent film forming process, Pc: cover side water repellent film forming process, Ppx: pin side water repellent film attaching process, Ppy: pin side water repellent film baking process, Pcx: cover side water repellent film attaching process, Pcy : Cover side water repellent film firing process, Q: surface water repellent film forming process, Qpx: pin side surface water repellent film attaching process, Qpy: pin side surface water repellent film firing process, Qcx: cover side surface water repellent film attaching process , Qcy: Cover side surface water-repellent film firing process

Next, an embodiment according to the present invention will be given and described in detail with reference to the drawings.

First, the cover-equipped sensor 1 according to the first embodiment will be described with reference to FIGS.

As shown in FIGS. 1, 2 and 3, the sensor with cover 1 according to the first embodiment is roughly divided into a base portion 3 for holding four electrode pins 2a and 2b, and electrode pins 2a and 2b. The sensor element 4 includes a sensor cover 4 having a predetermined air permeability that covers the sensor element 4 when the sensor element 4 is connected to the base unit 3 and used. In this case, the base portion 3 holding the four electrode pins 2a and 2b includes, as components, two pin assemblies 7, a circular bottom plate portion 11d to which the two pin assemblies 7 are attached, and an outer periphery of the bottom plate portion 11d. A chassis member 11 integrally formed with a cylindrical peripheral side plate portion 11s raised from a base member 12, a base member 12 for holding and fixing the two pin assemblies 7 to the chassis member 11, and a base member 12 provided upright. A shielding plate 13 is provided. Further, the sensor cover 5 is fixed to the base member 12 provided with the shielding plate 13 to obtain the base cover assembly 8.

The sensor cover 5 uses a porous cover 5s having a predetermined gas permeability. As shown in FIG. 2, the porous cover 5s is formed in an inverted cup shape by a cylindrical portion 5sf and a top surface portion 5su that closes the upper end of the cylindrical portion 5sf. The dimensions of the exemplified porous cover 5s are a diameter 12 [mm], a height 6 [mm], and a thickness 1 [mm]. The porous cover 5s is prepared by mixing the porous ceramic C with a ceramic powder raw material and one or more additives, and granulating a granulated material having a predetermined particle size. After the primary molding is performed by the primary pressure, a green compact having a particle size in the range of 0.1 to 1.0 [mm] is obtained by primary firing at a predetermined primary heating temperature. If the material is subjected to secondary molding at a predetermined secondary pressure and then subjected to secondary firing at a predetermined secondary heating temperature, when used in a gas sensor, the required gas permeability and required mechanical strength ( Both of the bending strength can be sufficiently secured.

As shown in FIG. 3, the pin assembly 7 includes a pin stay 15 formed of an insulating material, two electrode pins 2a and 2b formed in a rod shape using a conductive material, and two pin bases 16a and 16b formed in a cylindrical shape. The pin assembly 7 is assembled by a pin assembly process. In the pin assembly process, the two electrode pins 2a and 2b are press-fitted into the two holes formed in the pin stay 15, respectively, and the pin bases 16a and 16b are fitted into the electrode pins 2a and 2b. By fixing 16b to the pin stay 15 by glass bonding or the like, the electrode pins 2a and 2b are prevented from being removed from the pin stay 15. Therefore, the pin stay 15 and the pin bases 16 a and 16 b constitute a part 3 p of the base portion 3.

The base cover assembly 8 is fixed to the base member 12 made of alumina or the like by fusing the shielding plate 13 also made of alumina or the like and the sensor cover 5 made of porous ceramics or the like by glass bonding or the like. Obtained by the base cover assembly process.

On the other hand, on the surfaces of the pin assembly 7 and the base cover assembly 8 assembled in this way, a predetermined film thickness using the weather-resistant water-repellent material Rt by the water-repellent film forming step P shown in FIGS. A weather-resistant water repellent film 6t (FIGS. 1 and 3) having Dt is formed.

Next, a method of forming the weather-resistant water repellent film 6t for the pin assembly 7 and the base cover assembly 8 will be described with reference to the process diagrams shown in FIGS. 4 and 5 and FIGS.

In the water repellent film forming step P, the weather resistant water repellent film is formed on the surface of the pin assembly 7 described above, that is, at least a part of the pin assembly 7 in which at least the electrode pins 2a and 2b and the part 3p of the base part 3 are assembled. The pin-side water-repellent film forming step Pp for forming Dt and the above-described base cover assembly 8, that is, the surface of at least a part of the base cover assembly 8 in which the remaining portion 3r of the base portion 3 and the sensor cover 5 are assembled are weather-resistant. And a cover side water repellent film forming step Pc for forming the water repellent film 6t. In this case, the pin-side water-repellent film forming step Pp includes a pin-side water-repellent film attaching step including an immersion process in which the pin assembly 7 is immersed in a water-repellent treatment liquid using the weather-resistant water-repellent material Rt for a predetermined time. After completion of the pin-side water-repellent film adhesion step Ppx, the pin-side water-repellent film firing step Ppy for heating and firing at a predetermined temperature and time after the pin assembly 7 to which the water-repellent treatment liquid is adhered is dried at room temperature. And the cover-side water-repellent film forming step Pc includes a dipping process for immersing the base cover assembly 8 in a water-repellent liquid using the weather-resistant water-repellent material Rt for a predetermined time. After the film adhesion process Pcx and the cover-side water-repellent film adhesion process Pcx are finished, the base cover assembly 8 to which the water-repellent treatment liquid is adhered is dried at room temperature and then heated and fired at a predetermined temperature and time. It includes the over-side water-repellent film baking process Pcy.

The details will be described below. First, the predetermined number of assembled pin assemblies 7 or base cover assemblies 8 are accommodated in the processing basket 21 shown in FIGS. 6 and 7 (S1, S10). Then, the processing basket 21 containing the pin assembly 7 or the base cover assembly 8 is immersed in a processing tank containing a water repellent processing liquid for a set time Ts (for example, about 30 [seconds]) (S2, S11). In this case, a predetermined weather resistant water repellent material Rt is used for the water repellent treatment liquid. Specifically, the main material is a silicone resin, preferably a silicone resin, added with 3% of a transition metal compound, preferably niobium pentoxide, and stirred and mixed using a stirrer or ultrasonic wave. Viscosity is important for the water-repellent treatment liquid. When the viscosity is too small or too large, the desired film thickness Dt of the weather-resistant water-repellent film 6t, that is, a film in the range of 0.3 to 1.0 [μm]. Since the thickness Dt cannot be obtained, the thickness Dt is appropriately set by experiments or the like so that a desired film thickness Dt can be obtained.

When the set time Ts has elapsed after immersion, the treatment basket 21 is removed from the water repellent treatment liquid. In this case, the length of the set time Ts is as important as the water repellent treatment liquid. That is, since the length of the set time Ts greatly affects the film thickness Dt of the weather-resistant water-repellent film 6t, the length of the set time Ts is also set appropriately by experiment or the like, similarly to the above viscosity, and the desired film thickness Dt is set. To be able to get. By selecting the film thickness Dt of the weather-resistant water repellent film 6t within the range of 0.3 to 1.0 [μm], sufficient water repellency can be achieved without affecting the detection gas permeability or manufacturability. Can be secured. In the manufacturing method according to the present embodiment, since the pin assembly 7 and the base cover assembly 8 are immersed in a water repellent treatment liquid using the weather resistant water repellent material Rt for a predetermined set time Ts, the weather resistant repellent is included. A desirable film thickness Dt of 0.3 to 1.0 [μm] can be easily and reliably formed as the water film 6t.

On the other hand, the pin assembly 7 or the base cover assembly 8 to which the water repellent treatment liquid is attached is drained in a state of being accommodated in the treatment basket 21, and thereafter, at room temperature over a set time Tx (for example, about 10 minutes). Drying is performed (S3, S12). And if it dries at room temperature over the set time Tx, it is stored in a dedicated furnace, the temperature of the dedicated furnace is set to around 200 [° C.], and the baking process (hereinafter, about 60 [minute]) is performed for the set time Th In addition, after that, the temperature of the dedicated furnace is set to around 400 [° C.], and then the baking process (hereinafter, about 60 minutes) is performed for a set time (hereinafter referred to as “baking process”). The post-baking process is described (S4, S13). As will be described later, the baking process in these two stages is important. In particular, the latter baking process greatly affects the performance related to heat resistance, acid resistance and durability. After performing the above processing, room temperature cooling is performed (S5, S14). Thereby, the pin assembly 7 and the base cover assembly 8 in which the weather resistant water repellent film 6t made of the weather resistant water repellent material Rt having the predetermined film thickness Dt on the surface can be obtained.

By using such a pin assembly 7 and the base cover assembly 8, even if condensation occurs in the gas sensor, the surface 3f of the base portion 3 of the pin assembly 7 has water repellency and is held by the base portion 3. Short circuit due to moisture between the electrode pins 2a and 2b is effectively prevented. Further, even if acidic drain water lands on the gas sensor, the surface of the sensor cover 5 of the base cover assembly 8 has acid-resistant and durable water repellency, so that the drain water penetrates into the gas sensor and the electrode pins 2a, Short circuit due to drain water between 2b is also effectively prevented. As described above, since the prevention of short circuit between the electrode pins 2a and 2b can be realized very easily, there is no risk of failure even in a severe installation environment or a sensor with a cover installed over a long period of time. Can increase the sex.

Then, after the weather-resistant water repellent film 6t is formed on the pin assembly 7, the sensor element 4 is connected between the electrode pins 2a and 2b as shown in FIGS. In this case, the sensor element 4 is a gas sensor element 4s for sensing gas, and a pair of lead portions 4a and 4b derived from the gas sensor element 4s are directly joined to the vicinity of the upper ends of the electrode pins 2a and 2b, respectively, by welding. In this case, the weather-resistant water-repellent film 6t is also formed on the surfaces of the electrode pins 2a and 2b, but the thickness Dt of the weather-resistant water-repellent film 6t is as thin as about 0.3 to 1.0 [μm]. For this reason, problems such as weakening of the bonding strength and occurrence of burning residue do not occur. However, a method may be adopted in which only the portion where the gas sensor element 4s is welded is removed in advance or the weather-resistant water-repellent film 6t is not formed only on that portion (see FIG. 9). Thereafter, the base cover assembly 8 is assembled to the pin assembly 7.

Thereby, the sensor with cover 1 shown in FIGS. 1 and 2 in which the weather-resistant water repellent film 6t having the film thickness Dt is formed in the portion shown in FIG. 9 can be obtained. The illustrated sensor 1 with a cover is a gas sensor that uses a gas sensor element 4 s for the sensor element 4 and a porous cover 5 s having a predetermined gas permeability for the sensor cover 5. By applying the cover-equipped sensor 1 to such a gas sensor, there is an advantage that it is possible to contribute to expansion of the use environment and improvement of reliability. The porous cover 5s subjected to the weather-resistant water repellent treatment has a film thickness Dt of 0.3 to 1 on the surface of the porous cover 5s formed of the porous ceramics C as shown in the enlarged view of the extraction shown in FIG. A weather resistant water repellent film 6t of 0.0 [μm] is formed (coated).

In this case, since the pores are formed by the space around the contact surface serving as the grain boundary, the weather-resistant water repellent film 6t is coated on all or part of the surface of the particle k. However, the pores are not filled, and a predetermined gas permeability is ensured by the gas passage along the pores. At this time, the width of the pores is less than 500 [μm], and water repellency (non-wetting) is ensured by the weather-resistant water-repellent film 6 t even if moisture adheres. Therefore, by subjecting the porous cover 5s to such a water repellent treatment, it is possible to effectively prevent moisture from penetrating into the porous cover 5s, and the environment with much moisture and its acidic drain water scatter. Even under such a use environment, it is possible to protect the parts (the gas sensor element 4s, the connection part, etc.) arranged on the inner side, it is difficult for dust to enter, clogging, and further, the gas permeability decreases ( (Deterioration) can be prevented, so that detection accuracy can be maintained and reliability can be ensured.

Moreover, since the water repellent treatment is applied to the pin assembly 7 and the base cover assembly 8 by the manufacturing method according to the present embodiment, a synergistic effect based on both water repellent treatments, that is, to the outside of the porous cover 5s. Has a first water-repellent effect based on the weather-resistant water-repellent film 6t applied to the surface of the porous cover 5s that prevents the intrusion of unnecessary moisture. Even if it becomes a generation factor, a synergistic effect due to the second water-repellent effect that prevents a short circuit between the electrode pins 2a and 2b based on the weather-resistant water-repellent film 6t applied to the surface of the pin assembly 7 can be enjoyed. Therefore, the cover-equipped sensor 1 including the weather-resistant water-repellent film 6t that is strong against both moisture caused by the internal environment and moisture caused by the external environment can be obtained, and is optimal for use in a gas sensor or the like.

Next, a description will be given of confirmation experiments conducted for each characteristic such as heat resistance and acid resistance. FIG. 10 shows the results of a heat resistance test when various transition metal compounds are added to a silicone resin as a water repellent material. In the graph, the Y axis is the water repellency characteristic indicated by the contact angle [°] of water, and it is generally judged that the contact angle is 90 [°] or more and that there is water repellency. It was evaluated. For this reason, the pass line for judging that there is water repellency is indicated by Lp in the figure. In the legend of this graph, “1” is only silicone resin, “2” is addition of niobium pentoxide to silicone resin, “3” is addition of manganese oxide (MnO ₂ ) to silicone resin, and “4” is silicone. Add tantalum oxide (TaO ₃ ) to the resin, “5” adds nickel oxide (NiO) to the silicone resin, “6” adds niobium disilicide (NbSi ₂ ) to the silicone resin, “7” is hydrophobic silica This is the case. In either case, a heat and durability test at 400 [° C.] was performed on the heat-dried product of FIG. Of these, only the one obtained by adding niobium pentoxide to the silicone resin “2” withstood the durability up to 500 [hours].

FIG. 11 shows the results of an acid resistance test performed on each of the above samples in the case of only the pre-stage baking process in S4 and S13 of FIGS. 4 and 5 and the case where the post-stage baking process was added thereafter. Show. The test method was evaluated by the water repellency after boiling at 60 [min] and 240 [min] in an aqueous solution obtained by adding 6 [%] sulfuric acid to 50 [%] nitric acid. In FIG. 11, when HT1 is heated at 200 [° C] and 1 [H], HT2 is heated at 400 [° C] and 1.5 [H], when AB1 is acid boiling 60 [Min], AB2 is acid In the case of boiling 240 [Min], each is shown. As a result, the temperature of the dedicated furnace is set to around 200 [° C.], and the baking process performed only for the set time Th (for example, about 60 [minute]) is all rejected, but the temperature of the dedicated furnace is set to 400 If it is set to around [° C.] and a baking process is performed over a set time Ti (for example, about 60 [minutes]), only “1” silicone resin and “7” hydrophobic silica Everything else passed.

Fig. 12 shows the water repellency and gas permeability with respect to the amount of niobium pentoxide added (Wt [%]) for a water-repellent material in which niobium pentoxide is added to a silicone resin that is excellent in both heat resistance and acid resistance. The results are shown. The water repellency was determined in the same manner as described above. As for the gas permeability, the N2 gas permeability was measured, and it was determined to be acceptable when the transmittance was 50% or more. As a result, as the addition amount of niobium pentoxide increases, the gas permeability is maintained at 50% or more, but it is surely lowered, and the contact angle is the most when the addition amount is around 3%. It was found that the water repellency was high.

FIG. 13 shows the change in the contact angle when the temperature of the water-repellent material in which 3% of niobium pentoxide is added to the silicone resin is changed in the subsequent baking process in FIGS. is there. At this time, it is after performing the pre-stage baking process of the figure. As a result, the temperature of the post-baking treatment becomes the highest in water repellency in the vicinity of 400 [° C.], and then the water repellency is deteriorated, and it is confirmed that the water repellency disappears when the temperature exceeds 550 [° C.]. It was done.

FIG. 14 shows the results of confirming the water repellency of the water-repellent material in which 3% of niobium pentoxide is added to the silicone resin with respect to the keeping time of the temperature of the subsequent baking treatment. It was confirmed that the water repellency was improved as the keep time was increased from 0.5 [hour].

FIG. 15 is a photograph showing the surface state of the weather-resistant water repellent film 6t in the case of only the pre-baking treatment in FIGS. 4 and 5 for the water repellent material in which 3% of niobium pentoxide is added to the silicone resin. 16 is a photograph showing the surface state of the weather-resistant water-repellent film 6t when a post-baking process is added to the pre-baking process in FIGS. 4 and 5 for a water-repellent material in which 3% of niobium pentoxide is added to the silicone resin. It is. From FIG. 16, it is surmised that when post-baking treatment is applied, the water repellency is increased and the acid resistance is increased by precipitation of metal particles.

From the above results, the best conditions for heat and acid resistance and water repellency are as follows: a water repellent material in which 3% of niobium pentoxide is added to a silicone resin is subjected to a heat treatment of 400 ° C. after a heat treatment of 200 ° C. It was confirmed that it was applied at least 30 minutes.

Next, the cover-equipped sensor 1 according to the second embodiment will be described with reference to FIGS.

As shown in FIGS. 17 to 19, the sensor with cover 1 according to the second embodiment is provided with a weather-resistant water-repellent material different from the weather-resistant water-repellent film 6t on the weather-resistant water-repellent film 6t described above. A weather-resistant surface water-repellent film 6c having at least one layer using Rc and having a predetermined film thickness Dc is formed, and after the water-repellent film forming process P is completed, the weather resistance A surface water-repellent film forming step Q for forming a weather-resistant surface water-repellent film 6c on the water-repellent film 6t is provided.

Hereinafter, a method of forming the weather-resistant surface water-repellent film 6c will be described with reference to the process diagrams shown in FIGS.

In the surface water-repellent film forming step Q, the pin assembly 7 obtained in the pin-side water-repellent film forming step Pp is used as a water-repellent treatment liquid using the weather-resistant water-repellent material Rc for forming the weather-resistant surface water-repellent film 6c. Pin-side surface water-repellent film adhering step Qpx including a dipping process for immersing in the substrate for a predetermined time, and after completion of this pin-side surface water-repellent film adhering step Qpx, the pin assembly 7 to which the water-repellent treatment liquid is adhered is dried at room temperature And a pin-side surface water-repellent film firing step Qpy which is heated and fired at a predetermined temperature and time, and the base cover assembly 8 obtained in the cover-side water-repellent film forming step Pc is used as a weather-resistant surface water-repellent film. A cover-side surface water-repellent film adhering step Qcx including a dipping process for immersing in a water-repellent treatment liquid using the weather-resistant water-repellent material Rc forming 6c for a predetermined time, and a cover-side surface water-repellent film adhering step Qcx. After the end, Repellent water treatment solution is included was a cover side surfaces water-repellent film firing step Qcy of firing by a predetermined temperature and time base cover assembly 8 after room temperature drying adhesion.

In FIG. 20, S21 to S27 are the same as the steps from S1 to S5 in FIG. 4, and in FIG. 21, S41 to S47 are the same as the steps from S10 to S14 in FIG. In this case, S4 in FIG. 4 is described separately as S25 and S26 in FIG. 20, and S13 in FIG. 5 is described as S45 and S46 in FIG. Therefore, the cover-equipped sensor 1 according to the second embodiment basically uses the pin assembly 7 obtained in S5 of FIG. 4 and the base cover assembly 8 obtained in S14 of FIG. Can be used.

In forming the weather-resistant surface water-repellent film 6c, first, a predetermined number of assembled pin assemblies 7, that is, the pin assembly 7 obtained in S5 in FIG. 4 (S27 in FIG. 20) or S14 in FIG. The base cover assembly 8 obtained in (S47 in FIG. 21) is accommodated in the processing basket 21 shown in FIGS. 6 and 7 (S28, S48). Then, the processing basket 21 containing the pin assembly 7 or the base cover assembly 8 is placed in a processing tank containing a water-repellent treatment liquid using a weather-resistant water-repellent material Rc for forming the weather-resistant surface water-repellent film 6c for a set time Ts. Immersion is performed only (for example, about 30 seconds) (S29, S49). For this water repellent treatment liquid, a weather resistant water repellent material Rc different from the weather resistant water repellent material Rt is used. Specifically, a dispersion obtained by adjusting the dispersion of the PTFE fine particles to an appropriate concentration and stirring and mixing using a stirrer or an ultrasonic wave is used. Viscosity is important for this water-repellent treatment liquid. If the viscosity is too small or too large, a desired film thickness Dc of the weather-resistant surface water-repellent film 6c, that is, a range of 0.15 to 0.5 [μm]. Therefore, the desired film thickness Dc can be obtained by setting as appropriate through experiments or the like.

When the set time Ts has elapsed after immersion, the treatment basket 21 is removed from the water repellent treatment liquid. In this case, the length of the set time Ts is as important as the viscosity of the water repellent treatment liquid. That is, since the length of the set time Ts greatly affects the film thickness Dc of the weather-resistant surface water-repellent film 6c, the length of the set time Ts is set as appropriate by experiments or the like, similarly to the above viscosity, and the desired film thickness Dc. To be able to get. By selecting the film thickness Dc of the weather-resistant surface water-repellent film 6c within the range of 0.15 to 0.5 [μm], sufficient repellent properties can be obtained without affecting the detection gas permeability and manufacturability. Aqueous property can be secured. In the manufacturing method according to this embodiment, since the pin assembly 7 and the base cover assembly 8 are included in the water repellent treatment liquid using the weather resistant water repellent material Rc for a predetermined set time Ts, the weather resistant surface A desired film thickness Dc of 0.15 to 0.5 [μm] can be easily and reliably formed as the water repellent film 6c.

On the other hand, the pin assembly 7 or the base cover assembly 8 to which the water repellent treatment liquid is attached is drained in a state of being accommodated in the treatment basket 21, and thereafter, at room temperature over a set time Tx (for example, about 10 minutes). Drying is performed (S30, S50). And if it dried at normal temperature over setting time Tx, it will move to a heat drying and baking jig | tool (S31, S51). Next, it is accommodated in a dedicated furnace, the temperature of the dedicated furnace is set to around 200 [° C.], and heat drying is performed for a set time Th (for example, about 60 [minutes]) (S32, S52). Further, after that, the temperature of the dedicated furnace is set to around 400 [° C.], and the firing process is performed for a set time Ti (for example, about 60 [minutes]) (S33, S53). As will be described later, the heat treatment in these two stages is important. In particular, the baking treatment at the temperatures of S33 and S53 greatly affects the heat-resistant and acid-resistant durability performance. After performing the above processing, room temperature cooling is performed (S34, S54). Thereby, the surface of the pin assembly 7 and the base cover assembly 8 has a film thickness D composed of the weather-resistant water-repellent film 6t made of the weather-resistant water-repellent material Rt and the weather-resistant surface water-repellent film 6c made of the weather-resistant water-repellent material Rc. A bilayer film is formed.

With the above-described configuration, even if condensation occurs in the gas sensor, the weather resistance related to water repellency on the surface 3f of the base portion 3 in the pin assembly 7 is further improved, and the electrode pin held by the base portion 3 Short circuit due to moisture between 2a and 2b is effectively prevented. Further, even if acidic drain water lands on the gas sensor, the surface of the sensor cover 5 of the base cover assembly 8 is further improved in acid resistance and durable water repellency. A short circuit due to drain water between the pins 2a and 2b is also effectively prevented. As described above, since the prevention of short circuit between the electrode pins 2a and 2b can be realized very easily, there is no risk of failure even in a severe installation environment or a sensor with a cover installed over a long period of time. The sex can be increased.

Then, after the weather-resistant weather-resistant surface water-repellent film 6c is formed on the pin assembly 7, the sensor element 4 is connected between the electrode pins 2a and 2b as shown in FIGS. In this case, the sensor element 4 is a gas sensor element 4s for sensing gas, and a pair of lead portions 4a and 4b derived from the gas sensor element 4s are directly joined to the vicinity of the upper ends of the electrode pins 2a and 2b, respectively, by welding. In this case, the weather-resistant surface water-repellent film 6c is also formed on the surfaces of the electrode pins 2a and 2b, but the thickness Dc of the weather-resistant surface water-repellent film 6c is about 0.15 to 0.5 [μm]. Therefore, there are no problems such as weak bonding strength or burning residue. However, a method may be adopted in which only the portion where the gas sensor element 4s is welded is removed in advance or the weather-resistant surface water-repellent film 6c is not formed only in that portion (see FIG. 19). Thereafter, the base cover assembly 8 is assembled to the pin assembly 7.

As a result, a weather-resistant water-repellent film 6t having a film thickness Dt is formed at the site shown in FIG. 19, and a weather-resistant surface water-repellent film 6c having a film thickness Dc is formed on the weather-resistant water-repellent film 6t. The covered sensor 1 shown in FIGS. 17 and 18 can be obtained. The illustrated sensor 1 with a cover is a gas sensor that uses a gas sensor element 4 s for the sensor element 4 and a porous cover 5 s having a predetermined gas permeability for the sensor cover 5. By applying the sensor with cover 1 to such a gas sensor, there is an advantage that it is possible to contribute to the expansion of the use environment and the improvement of the reliability.

Accordingly, the cover-equipped sensor 1 according to the second embodiment is also provided with a weather-resistant water-repellent film because the pores are formed by the space around the contact surface serving as the grain boundary in the same manner as the cover-equipped sensor 1 according to the first embodiment. The weather-resistant surface water-repellent film 6c added to 6t is coated on all or part of the surface of the particle k. However, the pores are not filled, and a predetermined gas permeability is ensured by the gas passage along the pores. At this time, the width of the pores is less than 500 [μm], and water repellency (non-wetting) is ensured by the weather-resistant water-repellent film 6 t even if moisture adheres. Therefore, by subjecting the porous cover 5s to such a water repellent treatment, it is possible to effectively prevent moisture from penetrating into the porous cover 5s, and the environment with much moisture and its acidic drain water scatter. Even under such a use environment, it is possible to protect the parts (the gas sensor element 4s, the connection part, etc.) arranged on the inner side, it is difficult for dust to enter, clogging, and further, the gas permeability decreases ( (Deterioration) can be prevented, so that detection accuracy can be maintained and reliability can be ensured.

Moreover, since the water repellent treatment is applied to the pin assembly 7 and the base cover assembly 8 by the manufacturing method according to the present embodiment, a synergistic effect based on both water repellent treatments, that is, to the outside of the porous cover 5s. Has a first water-repellent effect based on the weather-resistant water-repellent film 6t applied to the surface of the porous cover 5s that prevents the intrusion of unnecessary moisture. Even if it becomes a generation factor, a synergistic effect due to the second water-repellent effect that prevents a short circuit between the electrode pins 2a and 2b based on the weather-resistant water-repellent film 6t applied to the surface of the pin assembly 7 can be enjoyed. Therefore, the cover-equipped sensor 1 including the weather-resistant water-repellent film 6t that is strong against both moisture caused by the internal environment and moisture caused by the external environment can be obtained, and is optimal for use in a gas sensor or the like.

As described above, the weather-resistant surface having at least one layer using the weather-resistant water-repellent material Rc different from the weather-resistant water-repellent film 6 t on the weather-resistant water-repellent film 6 t and having a predetermined film thickness Dc. If the water-repellent film 6c is formed, the inner weather-resistant water-repellent film 6t can improve the fixing property and heat resistance to the surface of the sensor cover 5 and the like, and the outer weather-resistant surface water-repellent film. 6c can improve acid resistance and water vapor resistance more. Therefore, it is possible to maintain a more reliable water repellency performance in terms of weather resistance than before, and a water repellency structure that can maintain water repellency performance even when used in an exhaust gas environment such as a gas water heater. be able to.

Next, we will describe the confirmation experiment that was conducted by installing a sensor with a cover in a 400 ° C environment. FIG. 22 shows the results of a water repellent performance test after exposure of a weather resistant water repellent film in a 400 ° C. environment. In the graph, the Y axis is the water repellency characteristic indicated by the contact angle [°] of water, and it is generally judged that the contact angle is 90 [°] or more and that there is water repellency. It was evaluated. In the legend of this graph, “Comparative Example 1” is only the weather-resistant water-repellent film 6t, “Comparative Example 2” is only the weather-resistant surface water-repellent film 6c, and “Example” is an example of the present invention. In this case, the weather-resistant surface water-repellent film 6c is added to the weather-resistant water-repellent film 6t. Among these, those that endured durability up to 500 [hours] were those of only the weather-resistant water-repellent film 6t made of a material obtained by adding niobium pentoxide to the silicone resin of "Comparative Example 1" and "Example". The weather-resistant water-repellent film 6t was made of a material obtained by adding niobium pentoxide to a silicone resin, and the weather-resistant surface water-repellent film 6c was made of a sintered PTFE film.

Furthermore, a verification experiment that was conducted by installing a sensor with a cover in the exhaust gas environment of a gas water heater is described. FIG. 23 shows the results of a water repellent performance test after exposure of a weather resistant water repellent film in a gas water heater exhaust gas environment. In the graph, the Y axis is the water repellency characteristic indicated by the contact angle [°] of water, and it is generally judged that the contact angle is 90 [°] or more and is generally water repellant. It was evaluated. Further, in the legend of this graph, “Comparative Example 1” is only the weather-resistant water-repellent film 6t, “Comparative Example 2” is only the weather-resistant surface water-repellent film 6c, and “Example” is the weather-resistant water-repellent film 6t. This is a case where a weather-resistant surface water-repellent film 6c is added. Among these, those that endured up to 500 [hours] were composed of the sintered PTFE film of “Comparative Example 2”, and the weather-resistant water-repellent film 6t of “Example” was made of silicone resin with niobium pentoxide. The weather-resistant surface water-repellent film 6c is made of a PTFE sintered film.

It was confirmed that the examples according to the present invention exhibited water-repellent performance even when placed in a 400 ° C. environment or an exhaust gas environment of a gas water heater for a long time. Further, it was confirmed that “Comparative Example 1” and “Comparative Example 2” are also effective in either environment.

From the above results, 400 ° C. heat resistance and good conditions under the exhaust gas environment of the gas water heater are that the weather resistant water repellent film 6t is made of a material in which niobium pentoxide is added to a silicone resin, and the weather resistant surface water repellent film 6c is formed. It was composed of a sintered PTFE film.

FIG. 24 shows an SEM photograph of the weather resistant water repellent film 6t. The weather-resistant water-repellent film 6t has niobium pentoxide embedded in a silicone resin, contributing to an improvement in heat resistance. The unevenness on the surface can also contribute to the fixability of the weather-resistant surface water-repellent film 6c which is the second layer. Further, FIG. 25 shows an SEM photograph of the weather-resistant surface water-repellent film 6c added to the weather-resistant water-repellent film 6t. The weather-resistant surface water-repellent film 6c is covered with a PTFE sintered film, and contributes to acid resistance and water vapor resistance.
Although the best embodiment has been described in detail above, the present invention is not limited to such an embodiment, and the weather resistance, which is the gist of the present invention, in the detailed configuration, shape, material, quantity, numerical value, and the like. As long as it is within the range of a sensor with a cover on which a water repellent film is formed, it can be arbitrarily changed, added or deleted. For example, at least a part of the surface of the base portion 3 including the electrode pins 2a and 2b means a part or all of the surface, and at least a part of the surface of the sensor cover 5 is part or all of the surface. Is the meaning of the surface. Furthermore, although the two-layer structure has been described in the second embodiment, it is possible to form a multilayer structure in which various coupling agents are formed between the first layer and the surface layer to further improve the adhesion.

The present invention can be used for various sensors having the same sensor structure as well as the gas sensor using the exemplified gas sensor element and the porous cover, and the manufacturing method thereof.

Claims (20)

A cover-equipped sensor comprising: a base portion holding at least two or more electrode pins; a sensor element connected to the electrode pins; and a sensor cover having a predetermined air permeability that covers the sensor element by being assembled to the base portion. The weather-resistant water-repellent material using a silicone-based resin containing a transition metal compound on one or both of at least a part of the surface of the base part including the electrode pin and at least a part of the surface of the sensor cover A sensor with a cover, wherein a weather-resistant water-repellent film having a predetermined film thickness is formed. 2. The sensor with a cover according to claim 1, wherein the silicone resin is a silicone resin. The sensor with a cover according to claim 1, wherein the transition metal compound is niobium pentoxide (Nb ₂ O ₅ ). The film thickness of the weather-resistant water-repellent film is selected in the range of 0.3 to 1.0 [μm], and the water contact angle is 90 ° or more as the water repellency evaluation value, and the predetermined air permeability is set. The sensor with a cover according to claim 1, wherein the sensor is selected to be 50% or more. 2. The sensor with a cover according to claim 1, which is applied to a gas sensor having a porous cover. On the weather-resistant water-repellent film, a weather-resistant surface water-repellent film having at least one layer using a weather-resistant water-repellent material different from the weather-resistant water-repellent film and having a predetermined film thickness is formed. The sensor with a cover according to claim 1. The weather-resistant surface water-repellent film is made of PTFE (polytetrafluoroethylene) as the weather-resistant surface water-repellent material, and the weather-resistant surface water-repellent film is formed as a sintered film. Sensor with cover as described. A cover-equipped sensor comprising: a base portion holding at least two or more electrode pins; a sensor element connected to the electrode pins; and a sensor cover having a predetermined air permeability that covers the sensor element by being assembled to the base portion. In the method for manufacturing a sensor with a cover, a silicone system containing a transition metal compound on one or both of at least a part of the surface of the base part including the electrode pin and at least a part of the surface of the sensor cover A method for producing a sensor with a cover, comprising a water repellent film forming step of forming a weather resistant water repellent film having a predetermined film thickness from a weather resistant water repellent material using a resin. The water-repellent film forming step includes a pin-side water-repellent film forming step of forming the weather-resistant water-repellent film on at least a part of a surface of a pin assembly in which at least a part of the electrode pin and the base part is assembled; 9. A cover-side water-repellent film forming step for forming the weather-resistant water-repellent film on at least a part of a surface of a base cover assembly in which the remaining part of the base part and the sensor cover are assembled. The manufacturing method of the sensor with a cover of description. The pin-side water-repellent film forming step includes a pin-side water-repellent film attaching step including a dipping process in which the pin assembly is immersed in a water-repellent treatment liquid using the weather-resistant water-repellent material for a predetermined time, And a pin-side water-repellent film firing step in which the pin assembly to which the water-repellent treatment liquid is adhered is dried at room temperature and then heated and fired at a predetermined temperature and time after the end of the side water-repellent film attaching step. Item 10. A method for manufacturing a sensor with a cover according to Item 9. The cover-side water-repellent film forming step includes a cover-side water-repellent film attaching step including a dipping process in which the base cover assembly is immersed in a water-repellent treatment liquid using the weather-resistant water-repellent material for a predetermined time. And a cover-side water-repellent film firing step in which, after the side water-repellent film attaching step, the base cover assembly to which the water-repellent treatment liquid is attached is dried at room temperature and then heated and fired at a predetermined temperature and time. The manufacturing method of the sensor with a cover of Claim 9. The method for manufacturing a sensor with a cover according to claim 8, wherein the silicone resin is a silicone resin. The method for manufacturing a sensor with a cover according to claim 8, wherein the transition metal compound is niobium pentoxide. The film thickness of the weather-resistant water-repellent film is selected in the range of 0.3 to 1.0 [μm], and the water contact angle is 90 ° or more as the water repellency evaluation value, and the predetermined air permeability is set. The method for manufacturing a sensor with a cover according to claim 8, wherein 50% or more is selected. After completion of the water-repellent film forming step, the weather-resistant water-repellent film has at least one layer using a weather-resistant water-repellent material different from the weather-resistant water-repellent film and has a predetermined film thickness. The method for manufacturing a sensor with a cover according to claim 9, further comprising a surface water-repellent film forming step of forming a weather-resistant surface water-repellent film. 16. The method for manufacturing a sensor with a cover according to claim 15, wherein the weather-resistant water-repellent material forming the weather-resistant surface water-repellent film uses PTFE. In the surface water-repellent film forming step, the pin assembly obtained in the pin-side water-repellent film forming step is used as a water-repellent treatment liquid using a weather-resistant water-repellent material for forming the weather-resistant surface water-repellent film. After the pin-side surface water-repellent film adhering step including the dipping process for dipping for a predetermined time, and after the pin-side surface water-repellent film adhering step is completed, the pin assembly to which the water-repellent treatment liquid is adhered is dried at room temperature and a predetermined temperature is reached. And a pin-side surface water-repellent film baking step of heating and baking according to time. 16. The method of manufacturing a sensor with a cover according to claim 15. The method for manufacturing a sensor with a cover according to claim 17, wherein the predetermined temperature is 320 ° C to 420 ° C. In the surface water-repellent film forming step, the base cover assembly obtained in the cover-side water-repellent film forming step is used as a water-repellent treatment liquid using a weather-resistant water-repellent material that forms the weather-resistant surface water-repellent film. After the cover-side surface water-repellent film adhering step including the dipping process for immersing for a predetermined time, and after the cover-side surface water-repellent film adhering step, the base cover assembly to which the water-repellent treatment liquid is adhered is dried at room temperature, The cover-side surface water-repellent film baking step of heating and baking according to the temperature and time of the step, the method for producing a sensor with a cover according to claim 15. The method for manufacturing a sensor with a cover according to claim 19, wherein the predetermined temperature is 320 ° C to 420 ° C.

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