【考案の詳細な説明】 産業上の利用分野 本考案は水などの液体を収納する容器に取付けられ、容
器内の液量を検知する液位検知装置に関するもので、例
えば電気ポットの湯の量を検知し、湯の残量が限界に達
したことを自動的に検知するためのものである。特にこ
の電気ポットの場合、容器に取付けたヒータにより内部
の水を加熱するため、水の残量を確実に検知することは
空炊き防止の上に非常に重要である。The present invention relates to a liquid level detection device which is attached to a container that stores liquid such as water and detects the amount of liquid in the container. For example, the amount of hot water in an electric pot. To automatically detect that the remaining amount of hot water has reached the limit. Particularly in the case of this electric pot, since the water inside is heated by the heater attached to the container, it is very important to reliably detect the remaining amount of water in order to prevent empty cooking.
従来の技術 従来の電気ポットなどの液体容器における液位表示は、
内部の液量が外部から透視できる液量表示窓を設けるこ
とが最も一般的な構成である。しかし、これは使用者の
注意をひくには弱く見すごされることが多いし、液量表
示窓から外れるまで液量が低下した時には特に判別しが
たいものである。また、単なる液位の表示にすぎず液位
を自動的に検知して各種の制御を行う目的には使用でき
ないものである。そこで、液量透視式の表示とは別に一
定の液位まで低下した時にそれを自動的に検知して点灯
やブザーで警告するとともに内容液の加熱を停止するこ
とが行われている。Conventional technology Liquid level display in conventional liquid containers such as electric pots
The most common configuration is to provide a liquid volume display window through which the liquid volume inside can be seen through from the outside. However, this is often overlooked weakly to attract the user's attention, and it is particularly difficult to distinguish when the liquid amount decreases until it comes out of the liquid amount display window. Further, it is merely a display of the liquid level and cannot be used for the purpose of automatically detecting the liquid level and performing various controls. Therefore, in addition to the liquid volume transparent display, when the liquid level drops to a certain level, it is automatically detected and a warning is given by lighting or a buzzer, and heating of the content liquid is stopped.
この目的に使用する従来の液位検知装置は第３図に示す
ような構成であった。第３図において、液体容器１に取
付けられた透明な液位管２の最下端の中心を通る両側に
発光素子３と受光素子４を対峙して取付けるとともに、
液位管２の中に遮光フロート５を入れ、液位管２の液位
が下がるに従って低下して来る遮光フロート５が所定の
レベルまで低下して発光素子３と受光素子４の間の光路
を遮断することにより、液位が下限に達したことを検知
できるようにしている。The conventional liquid level detecting device used for this purpose has a structure as shown in FIG. In FIG. 3, the light-emitting element 3 and the light-receiving element 4 are mounted facing each other on both sides passing through the center of the lowermost end of the transparent liquid level tube 2 mounted in the liquid container 1.
A light-blocking float 5 is placed in the liquid level tube 2, and the light-blocking float 5 which is lowered as the liquid level of the liquid level tube 2 is lowered to a predetermined level so that an optical path between the light emitting element 3 and the light receiving element 4 is provided. By shutting off, it is possible to detect that the liquid level has reached the lower limit.
考案が解決しようとする問題点 このような従来の構成では、液面に浮かべたフロートが
発受光素子の位置に来た時のみ検知可能なため、液位は
所定の１つのレベルしか検知できず、複数の液位を多段
階に検知することはできない。また、電気ポットの場
合、フロートを液位管内に設けることは熱湯に強いフロ
ート部材が必要となる上、湯あかなどがたまりやすく衛
生上も好ましくない。さらに、液位管を湯を外部にくみ
出す吐出管と共用化しようとする場合は、フロートが液
の流れを妨げるため使用できないという問題があった。Problems to be Solved by the Invention In such a conventional configuration, since the float floated on the liquid surface can be detected only when it reaches the position of the light emitting / receiving element, the liquid level can detect only one predetermined level. , Multiple liquid levels cannot be detected in multiple stages. Further, in the case of the electric pot, providing the float in the liquid level pipe requires a float member that is resistant to hot water, and is also unfavorable in terms of hygiene because hot water is easily accumulated. Further, when the liquid level tube is to be used also as a discharge tube for drawing hot water to the outside, there is a problem that the float cannot be used because it obstructs the flow of the liquid.
本考案はこのような問題点を解決するもので、衛生面を
配慮しているとともに発光素子及び受光素子の取付けが
容易であり、かつ安全で精度の高い液位検知装置の提供
を目的とするものである。The present invention solves such a problem, and an object thereof is to provide a safe and highly accurate liquid level detection device in consideration of hygiene, easy mounting of a light emitting element and a light receiving element. It is a thing.
問題点を解決するための手段 この問題点を解決するために本考案は、透明な液位管の
外壁近くに少なくとも一対の発光素子と受光素子を、前
記液位管の外壁に沿わして取付けられるように、その外
壁形状に合わせた凹部の対峙する位置に小空間をそれぞ
れ形成してなるホルダーに設けられたプリント基板の両
側端部に取付けて設け、前記一対の発光素子と受光素子
が前記小空間にそれぞれ嵌め入れられて対峙される構成
とし、前記発光素子の光軸が前記液位管の外壁からその
液位管の半径の1/10〜1/2内側でその液位管の半径と直
角に交わり、かつ前記受光素子と発光素子の中心を結ぶ
直線が前記発光素子の光軸と同一かまたはそれより前記
液位管の外側に位置するように、これら一対の発光素子
と受光素子が設けられてなるものであり、発光素子から
小空間を通して液位管内に入射した光がその液位置の中
に液体がない場合（中空の場合）には、小空間を通して
受光素子に到達するが、液位管内に液体がつまっている
場合には受光素子に到達しないようにして、液位管内の
液体の有無を検出し液位を検知するようにしたものであ
る。Means for Solving the Problems In order to solve this problem, the present invention is to mount at least a pair of a light emitting element and a light receiving element near the outer wall of a transparent level tube along the outer wall of the level tube. As described above, a pair of light emitting element and light receiving element are provided by being attached to both side ends of a printed circuit board provided in a holder formed with a small space at a position facing a concave portion matching the outer wall shape. The light axis of the light emitting element is 1/10 to 1/2 of the radius of the liquid level tube from the outer wall of the liquid level tube, and the radius of the liquid level tube is set so as to face each other by being fitted in small spaces. A pair of the light emitting element and the light receiving element such that a straight line that intersects with the light receiving element and the center of the light emitting element at the same time as the optical axis of the light emitting element or is located outside the liquid level tube with respect to the light axis. Is provided and emits light When the light that has entered the liquid level tube from the child through the small space reaches the light receiving element through the small space when there is no liquid in the liquid position (when it is hollow), the liquid is blocked in the liquid level tube. In this case, the liquid level is detected by detecting the presence or absence of liquid in the liquid level tube without reaching the light receiving element.
作用 この構成により、発光素子から小空間を通して液位管外
壁に入射した光は液位管の材料によって決まる屈折率に
よって液位管の中心方向に屈折して進むが、液位管の内
部が中空の場合、液位管の内壁にて再度中心から遠ざか
る方向に屈折し、液位管の内部中空を進んで再び内壁に
達して入射時とは逆の屈折で液位管の外部に出て来る。
一方、液位管の中に液体が満たされていると、液体の屈
折率は液位管の屈折率に近くなるため、液位管内壁であ
まり屈折せずほとんど直進する。そのため、液位管の中
に液体が満たされている場合は中空の場合と液位管の中
の光の経路が大きく異なり、液位管の中心方向に光が集
まる。従って、受光素子を、液位管に液体が満たされて
いる時には発光素子からの光が到達せず、中空の時にの
み到達する位置に設置することにより、受光素子に光が
到達したかどうかで発受光素子の高さ位置に液体がある
かどうかを遮光フロートなしに検知することができる。
また、プリント基板上の両側端部に発光素子と受光素子
を取付けたホルダーの凹部を、液位管の外壁に沿わして
取付けることにより、発光素子と受光素子の取付け位置
精度が確保されることとなる。Function With this configuration, light incident on the outer wall of the level tube from the light emitting element through the small space is refracted toward the center of the level tube due to the refractive index determined by the material of the level tube, but the inside of the level tube is hollow. In the case of, the inner wall of the liquid level tube again refracts in a direction away from the center, travels through the inner hollow of the liquid level tube, reaches the inner wall again, and comes out of the liquid level tube with the opposite refraction to that at the time of incidence. .
On the other hand, when the liquid is filled in the liquid level tube, the refractive index of the liquid is close to the refractive index of the liquid level tube, and therefore the inner wall of the liquid level tube hardly refracts and goes straight. Therefore, when the liquid is filled in the liquid level tube, the path of light in the liquid level tube is largely different from that in the case where the liquid level tube is hollow, and the light is collected in the central direction of the liquid level tube. Therefore, by arranging the light receiving element at a position where the light from the light emitting element does not reach when the liquid is filled in the liquid level tube and only when it is hollow, it is possible to determine whether the light reaches the light receiving element. It is possible to detect whether or not the liquid is present at the height position of the light emitting / receiving element without the light blocking float.
In addition, the mounting position accuracy of the light emitting element and the light receiving element can be ensured by mounting the recesses of the holder, which mounts the light emitting element and the light receiving element at both ends on the printed circuit board, along the outer wall of the liquid level tube. Becomes
実施例 第１図は本考案の一実施例による液位検知装置を示す液
位管の軸方向に垂直な断面図である。第１図において、
６はガラスなどの透明な材質による液位管である。７は
前記液位管６の外壁近くに設置された発光ダイオードな
どの発光素子で、小空間18から液位管６の方向に光を発
射する。そして、液位管６の外壁面において光はその液
位管６の材料の屈折率に応じてその液位管６の中心方向
に屈折して進む。この時、液位管６の中に液体がなく中
空の場合は第１図の実線と矢印で示すようにその液位管
６の内壁面で再び空中に出るため逆に屈折し、中心から
遠ざかる方向に進み、再び内壁面に達して液位管６の材
質内をより一層中心から遠ざかる方向に屈折してその液
位管６の外壁より外に出る。この位置には小空間19が形
成されているとともにフォトトランジスタなどの受光素
子８が設けてあり、液位管６を透過した光は前記小空間
19から受光素子38に到達し、受光される。一方、液位管
６内に液体が満たされている場合は液体の屈折率がその
液位管６の材料の屈折率と大差ないため、液位管６の内
壁面ではあまり屈折せず、第１図の破線と矢印で示した
ようにほとんど直進して受光素子８の位置には到達しな
い。従って、発光素子７と受光素子８の取付け高さにま
で液位があるかどうかを検知することができる。Embodiment 1 FIG. 1 is a sectional view of a liquid level detecting device according to an embodiment of the present invention, which is perpendicular to the axial direction of a liquid level tube. In FIG.
6 is a liquid level tube made of a transparent material such as glass. Reference numeral 7 denotes a light emitting element such as a light emitting diode installed near the outer wall of the liquid level tube 6, and emits light from the small space 18 toward the liquid level tube 6. Then, on the outer wall surface of the liquid level tube 6, light is refracted toward the center of the liquid level tube 6 according to the refractive index of the material of the liquid level tube 6. At this time, if there is no liquid in the liquid level tube 6 and it is hollow, as shown by the solid line and arrow in FIG. Then, the liquid reaches the inner wall surface again, refracts in the material of the liquid level tube 6 further away from the center, and goes out from the outer wall of the liquid level tube 6. At this position, a small space 19 is formed and a light receiving element 8 such as a phototransistor is provided, and the light transmitted through the liquid level tube 6 is the small space.
The light reaches the light receiving element 38 from 19 and receives light. On the other hand, when the liquid in the liquid level tube 6 is filled with the liquid, the refractive index of the liquid is not so different from the refractive index of the material of the liquid level tube 6, so that the inner wall surface of the liquid level tube 6 does not significantly refract, and As shown by a broken line and an arrow in FIG. 1, the light receiving element 8 does not reach the position of the light receiving element 8 almost straight. Therefore, it is possible to detect whether or not there is a liquid level up to the mounting height of the light emitting element 7 and the light receiving element 8.
本考案の液位検知装置においてその動作を確実なものに
するためには、液位管６内の液の有無による透過光経路
の差をできるだけ大きくする必要があり、そのために発
光素子７と受光素子８の液位管６の半径方向に対する取
付け位置が非常に重要となる。すなわち、発光素子７か
ら入射する光の軸が液位管６の中心に向かう場合は液の
有無による透過光経路差は全くなく、液位検知はできな
くなる。従って、入射光軸は液位管６の中心からずれる
ほどよいが、ずれすぎると液位管６の表面での反射が大
きくなり透過光が少なくなってしまう。ここで、本考案
者らは発光素子７の入射光の光軸を液位管６の外壁から
のその液位管６の半径の1/10〜1/2内側にてその液位管
６の半径と直角に交わるよう受光素子８を位置決めする
とともに、受光素子８と発光素子７を結ぶ直線がその発
光素子７の入射光軸と同一かまたはそれより液位管６の
外側に位置するよう受光素子８を位置決めするのが最も
良いことを見い出した。この時、発光素子７の光軸を液
位管６の外壁からその液位管６の半径の1/10より外側で
その液位管６の半径と直角に交わるように受光素子８を
設置した場合、上述したように光が液位管６の表面で反
射してしまい、液位管６の中に入る透過光が少なくなっ
て好ましくない。また一方、液位管６の半径の1/2より
も内側で液位管６の半径と直角に交わるように受光素子
８を設置した場合には、上述したように液体のある時と
ない時の透過光経路差がなくなり、液位検知ができない
こととなる。In order to ensure the operation of the liquid level detection device of the present invention, it is necessary to make the difference in the transmitted light path depending on the presence or absence of the liquid in the liquid level tube 6 as large as possible. The mounting position of the element 8 with respect to the radial direction of the liquid level tube 6 is very important. That is, when the axis of the light incident from the light emitting element 7 is directed to the center of the liquid level tube 6, there is no difference in the transmitted light path depending on the presence or absence of the liquid, and the liquid level cannot be detected. Therefore, it is better that the incident optical axis is deviated from the center of the liquid level tube 6, but if it is too deviated, reflection on the surface of the liquid level tube 6 becomes large and transmitted light becomes small. Here, the inventors of the present invention set the optical axis of the incident light of the light emitting element 7 inside the liquid level tube 6 from the outer wall of the liquid level tube 6 within 1/10 to 1/2 of the radius of the liquid level tube 6. The light receiving element 8 is positioned so as to intersect the radius at right angles, and the light receiving element 8 and the light emitting element 7 are received so that the straight line connecting the light receiving element 8 and the incident optical axis of the light emitting element 7 is located outside the liquid level tube 6 from that. It has been found that it is best to position the element 8. At this time, the light receiving element 8 is installed so that the optical axis of the light emitting element 7 intersects the outer wall of the liquid level tube 6 outside the radius 1/10 of the liquid level tube 6 at a right angle to the radius of the liquid level tube 6. In this case, the light is reflected on the surface of the liquid level tube 6 as described above, and the amount of transmitted light entering the liquid level tube 6 decreases, which is not preferable. On the other hand, when the light receiving element 8 is installed so as to intersect with the radius of the liquid level tube 6 at a right angle inside 1/2 of the radius of the liquid level tube 6, as described above, when there is liquid and when there is no liquid. Therefore, there is no difference in the path of the transmitted light, and the liquid level cannot be detected.
第１図の９は発光素子７と受光素子８の位置決めをする
とともに不要な光をしゃへいするホルダーであり、この
ホルダー９の枠体部分の内面側は液位管６の外壁の形状
に合わせて取付けできるように凹部となっており、その
凹部の対峙する位置に光の通過経路となる前記小空間1
8,19が形成され、かつ枠体部分の外側に発光素子７と受
光素子８に配線するためのプリント基板10が設けられて
いる。また、11はリード線である。ここで、ホルダー９
に設けられたプリント基板10の両側端部に、発光素子７
と受光素子８をそれぞれ小空間18,19に嵌め入れられて
対峙するように取付けていることにより、取付位置の精
度を確保している。Reference numeral 9 in FIG. 1 denotes a holder for positioning the light emitting element 7 and the light receiving element 8 and shielding unnecessary light. The inner surface side of the frame portion of the holder 9 is adjusted to the shape of the outer wall of the liquid level tube 6. The small space 1 has a concave portion so that it can be attached, and a light passage path is provided at a position facing the concave portion.
8 and 19 are formed, and a printed circuit board 10 for wiring to the light emitting element 7 and the light receiving element 8 is provided outside the frame portion. Further, 11 is a lead wire. Where the holder 9
The light emitting element 7 is provided on both side edges of the printed circuit board 10 provided on the
The light receiving element 8 and the light receiving element 8 are fitted into the small spaces 18 and 19 so as to be opposed to each other, thereby ensuring the accuracy of the mounting position.
第２図は液体容器12に連結された透明な液位管13にてペ
アーの発光素子、受光素子からなる本考案の液位検知装
置を取付けた場合の概略断面図で、14および15は受光素
子で、液位管をはさんでその反対側には２個の発光素子
（図示せず）がそれぞれ取付けられている。第２図では
第１図で示したホルダーに相当するものは解りやすいよ
うに省略してある。この第２図の例では液位管13は液体
容器12から液体16を外部にくみ出すための吐出管を兼ね
ている。このような場合、電気ポットなどではベローズ
ポンプなどで液体容器12内の空気を加圧することによっ
て吐出管から液体16を外にくみ出すのが一般的である。
従って、吐出管を兼ねた液位管13の水位はくみ出す際に
大きく変動するため、液位検知装置からの検知信号も短
時間の間にON−OFFをくり返し安定な検知信号が得られ
ず、誤動作の原因になる場合がある。そして、液位検知
装置からの検知信号はマイクロコンピュータ17などの制
御回路にインプットされ、各種の制御を行うことになる
が、前記のような誤動作を防ぐためには発光素子、受光
素子14,15の取付け位置に液体16がある場合のON信号
（またはOFF信号）、ない場合のOFF信号（またはON信
号）が所定の時間連続的に出力されていることをマイク
ロコンピュータ17で判定し、短時間の変動には影響され
ないようにするのが望ましい。この時間は通常の電気ポ
ットの場合、0.7秒〜1.5秒にするのが良い。すなわち、
ベローズポンプなどで液体容器12内の空気を加圧して吐
出管を兼ねた液位管13より液体16を外にくみ出す場合、
圧力変化による液位の変動が大体0.4秒前後であり、こ
れより精度上の信頼性を考えて0.7秒間は連続して出力
される時に正常な信号として処理するのが好ましい。ま
た、前記信号の時間が1.5秒をこえて連続して出力され
る信号を正常なものとした場合には、ポットなどの容器
を空炊きによって変色させたり、本来の機能を果たすこ
とができなくなるおそれがあり、これまた好ましくな
い。FIG. 2 is a schematic cross-sectional view when the liquid level detection device of the present invention consisting of a pair of light emitting element and light receiving element is attached to a transparent liquid level tube 13 connected to a liquid container 12, and 14 and 15 are light receiving elements. Two light-emitting elements (not shown) are mounted on the opposite side of the element across the liquid level tube. In FIG. 2, those corresponding to the holder shown in FIG. 1 are omitted for easy understanding. In the example of FIG. 2, the liquid level tube 13 also serves as a discharge tube for drawing the liquid 16 out of the liquid container 12 to the outside. In such a case, in an electric pot or the like, the liquid 16 is generally pumped out from the discharge pipe by pressurizing the air in the liquid container 12 with a bellows pump or the like.
Therefore, since the water level of the liquid level tube 13 which also serves as the discharge tube fluctuates greatly when pumping out, the detection signal from the liquid level detection device is repeatedly turned on and off within a short time, and a stable detection signal cannot be obtained. , It may cause malfunction. Then, the detection signal from the liquid level detection device is input to a control circuit such as the microcomputer 17 to perform various controls, but in order to prevent the malfunctions as described above, the light emitting element, the light receiving elements 14 and 15 The microcomputer 17 determines that the ON signal (or OFF signal) when the liquid 16 is present at the mounting position and the OFF signal (or ON signal) when there is no liquid 16 are continuously output for a predetermined time. It is desirable to be immune to fluctuations. In the case of an ordinary electric pot, this time should be 0.7 to 1.5 seconds. That is,
When the air in the liquid container 12 is pressurized by a bellows pump or the like and the liquid 16 is pumped out from the liquid level pipe 13 which also serves as a discharge pipe,
The fluctuation of the liquid level due to the pressure change is approximately 0.4 seconds, and it is preferable to process it as a normal signal when continuously output for 0.7 seconds in consideration of the reliability in accuracy. Further, when the signal is continuously output for more than 1.5 seconds and the signal is normally output, the container such as a pot may be discolored by empty cooking, or the original function cannot be achieved. There is a risk that this is also undesirable.
考案の効果 以上のように本考案によれば、従来のように液位管の中
にフロートを浮かべる必要がなく経済的であるだけでな
く、フロートが湯あかなどで汚れることもなく、衛生面
での効果もある。また、液位管を吐出管と共用した場合
にも吐出管の中の液体の流れを妨げるものがないため、
使用することが可能になる。さらに、従来の方式は所定
の１つの液位を検知できるだけであるが、本考案によれ
ば発光，受光素子のペアー数を増せばその数だけの液位
を検知できるため、より安全性の高い高機能な液位検知
装置を実現することができるという効果が得られる。Effect of the Invention As described above, according to the present invention, it is not necessary to float the float in the liquid level tube as in the past, which is economical, and the float is not contaminated by hot water, etc. There is also the effect of. Also, even when the level tube is also used as the discharge tube, there is nothing that obstructs the flow of the liquid in the discharge tube.
Can be used. Further, the conventional method can detect only one predetermined liquid level, but according to the present invention, if the number of pairs of light emitting and light receiving elements is increased, only that number of liquid levels can be detected, so that the safety is higher. The effect that a highly functional liquid level detection device can be realized is obtained.
また、本考案の構成によりホルダーのプリント基板に位
置決めして一対の発光素子と受光素子を取付けているこ
とにより、このホルダーを液位管の外壁に沿わして取付
けるだけで、発光素子と受光素子がそれぞれ液位管に対
して位置決めされるという効果が得られる。従って、プ
リント基板が位置ずれしても一対の発光素子と受光素子
もそれに伴って移動するため、液位管と一対の発光素子
と受光素子の位置関係において、位置決めが容易とな
り、透過光経路も、ホルダーに形成された小空間及びプ
リント基板の取付けによって自動的に位置合わせされる
ことになり、取付け精度が向上するという効果が得られ
る。さらに、ホルダーに小空間を形成し、この小空間の
みを通して発光及び受光を行うため、外来光（例えば各
種照明及び太陽光）による影響を受けにくく安定した水
位検知ができるという効果が得られる。Further, according to the configuration of the present invention, the pair of the light emitting element and the light receiving element are attached to the printed circuit board of the holder so that the light emitting element and the light receiving element can be simply attached along the outer wall of the liquid level tube. Is obtained with respect to each of the liquid level tubes. Therefore, even if the printed circuit board is displaced, the pair of the light emitting element and the light receiving element also move accordingly, which facilitates the positioning in the positional relationship between the liquid level tube and the pair of the light emitting element and the light receiving element, and also the transmitted light path. Since the small space formed in the holder and the printed circuit board are mounted, the positioning is automatically performed, and the effect of improving the mounting accuracy can be obtained. Furthermore, since a small space is formed in the holder and light emission and light reception are performed only through this small space, it is possible to obtain an effect that stable water level detection can be performed without being influenced by external light (for example, various kinds of illumination and sunlight).
第１図は本考案の一実施例による液位検知装置を示す液
位管の軸方向に垂直な断面図、第２図は本考案の液位検
知装置を液体容器に取付けた場合の例を示す概略断面
図、第３図は従来の液位検知装置の構成を示す概略断面
図である。 6,13……液位管、７……発光素子、8,14,15……受光素
子、９……ホルダー、10……プリント基板、11……リー
ド線、 12……液体容器、16……液体、18,19……小空間。FIG. 1 is a sectional view perpendicular to the axial direction of a liquid level tube showing a liquid level detecting device according to an embodiment of the present invention, and FIG. 2 is an example in which the liquid level detecting device of the present invention is attached to a liquid container. FIG. 3 is a schematic sectional view showing the structure of a conventional liquid level detecting device. 6,13 ... Liquid level tube, 7 ... Light emitting element, 8,14,15 ... Light receiving element, 9 ... Holder, 10 ... Printed circuit board, 11 ... Lead wire, 12 ... Liquid container, 16 ... … Liquid, 18,19 …… Small space.
───────────────────────────────────────────────────── フロントページの続き (72)考案者 木下 武司 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 (72)考案者 川崎 幸三 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 (56)参考文献 特開 昭50−137565（ＪＰ，Ａ) 実開 昭55−51777（ＪＰ，Ｕ) ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takeshi Kinoshita 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Kozo Kawasaki 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 56) References Japanese Unexamined Patent Publication No. 50-137565 (JP, A) Actually developed 55-51777 (JP, U)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1986155446UJPH0642180Y2 (en) | 1986-10-09 | 1986-10-09 | Liquid level detector |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1986155446UJPH0642180Y2 (en) | 1986-10-09 | 1986-10-09 | Liquid level detector |
| Publication Number | Publication Date |
|---|---|
| JPS6360925U JPS6360925U (en) | 1988-04-22 |
| JPH0642180Y2true JPH0642180Y2 (en) | 1994-11-02 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1986155446UExpired - LifetimeJPH0642180Y2 (en) | 1986-10-09 | 1986-10-09 | Liquid level detector |
| Country | Link |
|---|---|
| JP (1) | JPH0642180Y2 (en) |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012063329A (en)* | 2010-09-17 | 2012-03-29 | Welco Co Ltd | Liquid sensor |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0827293B2 (en)* | 1991-03-29 | 1996-03-21 | 日本光電工業株式会社 | Liquid sensor |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5551777U (en)* | 1978-10-02 | 1980-04-05 |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012063329A (en)* | 2010-09-17 | 2012-03-29 | Welco Co Ltd | Liquid sensor |
| Publication number | Publication date |
|---|---|
| JPS6360925U (en) | 1988-04-22 |
| Publication | Publication Date | Title |
|---|---|---|
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