JP4062477B2

JP4062477B2 - Liquid level detector

Info

Publication number: JP4062477B2
Application number: JP2000365242A
Authority: JP
Inventors: 孝之山浦
Original assignee: Nippon Seiki Co Ltd
Current assignee: Nippon Seiki Co Ltd
Priority date: 2000-11-30
Filing date: 2000-11-30
Publication date: 2008-03-19
Anticipated expiration: 2020-11-30
Also published as: JP2002168675A

Description

【０００１】
【発明の属する技術分野】
本発明は、液面検出装置に関するもので、特にフロートを備えた液面検出装置に関するものである。
【０００２】
【従来の技術】
従来の液面検出装置１は、図７から図１０に示すように例えば図示しない燃料タンクの液面に浮く図示しないフロートに連動するフロートアーム２と、このフロートアーム２の回動に伴って動くアームホルダ３と、アームホルダ３の軸部１４を軸支する本体フレーム４と、この本体フレーム４に固定される回路基板５と、この回路基板５上を摺動する摺動接点６を有しアームホルダ３に固定される接点保持部材７と、回路基板５に電気的に接続される端子８と、この端子８と図示しない外部回路とを接続するリード線９とを備え、液面の変動に伴い前記フロート、フロートアーム２、アームホルダ３を介して摺動接点６が回路基板５上を摺動することで回路基板５に設けた図示しない抵抗体によって生じる電圧変動をリード線９により、図示しない外部回路に出力するものが知られている。
【０００３】
フロートアーム２は金属製の棒状で、その先端に液面に浮く図示しないフロートを備えている。また、他方の端部１０は折り曲げられている。
【０００４】
アームホルダ３は合成樹脂からなり、フロートアーム２の折り曲げた端部１０が貫通する孔１１を有する保持部１２を備えるとともに、フロートアーム２を両側から保持する保持片３ａを備えている。この保持部１２と保持片３ａとにより、フロートアーム２はアームホルダ３に位置決め固定されている。また、アームホルダ３は胴部１３を挟んで２つに位置的に離間した軸部１４を備え、この軸部１４はアームホルダ３において同一軸上両端に位置して形成されており、胴部１３と軸部１４とは、その中心部に貫通した孔１５を備えた筒状である。さらに、アームホルダ３には胴部１３の近傍に後述する接点保持部材を位置決めする２つの位置決め部１６が形成されている。
【０００５】
また、アームホルダ３へのフロートアーム２の組み付けは、フロートアーム２の端部１０を保持部１２の孔１１に挿入し、保持部１２で回動可能に保持された端部１０の軸を中心に軸部１４の軸方向に回動させ、アームホルダ３の保持片３ａを弾性変形させてフロートアーム２を保持することで完了する。
【０００６】
本体フレーム４は合成樹脂で形成されており、２つのフレーム構成体１７，１８から構成されている。このフレーム構成体１７，１８それぞれにはアームホルダ３を回動可能に軸支するために、アームホルダ３の軸部１４を受ける軸受部１９，２０を備えている。
【０００７】
フレーム構成体１７には係止爪を備えた弾性片が４つ設けられており、他方のフレーム構成体１８には、前記係止爪が係合する係止部が同じく４つ設けられている。また、フレーム構成体１８にはピン２１が２本突出形成されており、フレーム構成体１７にはこのピン２１が貫通する孔２２が設けられている。フレーム構成体１７，１８の組み付け固定は、フレーム構成体１７，１８それぞれに設けた前記係止爪と前記係止部とを係合させ、孔２２から露出したピン２１の端部を熱溶着により変形させることで完了する。
【０００８】
フレーム構成体１８は、その一部を切り欠いた切り欠き部２３を備えている。この切り欠き部２３は、フレーム構成体１７とフレーム構成体１８とを組み付けた状態でガイド部２４を構成するものである。
【０００９】
回路基板５はセラミックからなり、その表面に導電体２５や図示しない抵抗体を備えている。この回路基板５はフレーム構成体１８に固定されている。
【００１０】
接点保持部材７は金属製の薄板状で、アームホルダ３の位置決め部１６に対応する貫通孔２６と回路基板５上を摺動する２つの摺動接点６とが設けられている。摺動接点６は接点保持部材７を例えばプレス加工により一体形成したものである。なお、接点保持部材７とアームホルダ３との組み付けは接点保持部材７の貫通孔２６にアームホルダ３の位置決め部１６を摺動接点６が回路基板７側に向くように挿入し、貫通孔２６から露出した位置決め部１６の先端を熱溶着した熱溶着部３ｂにより固定される。
【００１１】
【発明が解決しようとする課題】
しかしながら、このような液面検出装置１の場合、接点保持部材７の貫通孔２６とアームホルダ３の位置決め部１６とを熱溶着部３ｂにより固定していたが、このような熱溶着手段による固定方法では貫通孔２６と位置決め部１６との寸法公差上のガタツキを抑制することは困難である。すなわち、このガタツキに伴い摺動接点６が正規の位置からズレてしまい回路基板５に設けた図示しない抵抗体によって生じる電圧変動に悪影響を及ぼすことが懸念される。
【００１２】
本発明はこの点に鑑みてなされたもので、その主な目的は、アームホルダと接点保持部材とのガタツキを抑制することが可能な液面検出装置を提供せんとするものである。
【００１３】
【課題を解決するための手段】
本発明は、前記目的を達成するために、液面に浮くフロートを備えたフロートアームと、前記フロートアームを保持するアームホルダと、前記アームホルダを回動可能に備えた本体フレームと、前記本体フレームに固定される回路基板と、前記回路基板上を摺動する摺動接点を有する接点保持部材とを有し、前記アームホルダは、その板状部から突出形成された突起形状からなる位置決め部を備え、前記接点保持部材は、その基部において、前記位置決め部に対応する箇所に貫通孔からなる位置決め孔を備え、前記接点保持部材には、前記位置決め孔に前記位置決め部を挿通させる前の段階で、前記位置決め孔に連通する孔部を有する筒状部が、前記板状部側とは反対側となる前記基部の前面側において、前記位置決め孔を取り巻くように、予め前記基部に一体形成されてなり、前記基部と前記板状部とが密着するように、前記位置決め部を前記位置決め孔並びに前記孔部に挿通させて前記接点保持部材が前記アームホルダに対し位置決め保持される構成としたことを特徴とする。
【００１４】
また本発明は、液面に浮くフロートを備えたフロートアームと、前記フロートアームを保持するとともに回動支点に２つの軸部を備えたアームホルダと、前記アームホルダの軸部を各々軸支する２つの離間した軸受部で回動可能に保持する本体フレームと、前記本体フレームに固定される回路基板と、前記回路基板上を摺動する摺動接点を有する接点保持部材とを有し、前記アームホルダは、その板状部から突出形成された突起形状からなる位置決め部を備え、前記接点保持部材は、その基部において、前記位置決め部に対応する箇所に貫通孔からなる位置決め孔を備え、前記接点保持部材には、前記位置決め孔に前記位置決め部を挿通させる前の段階で、前記位置決め孔に連通する孔部を有する筒状部が、前記板状部側とは反対側となる前記基部の前面側において、前記位置決め孔を取り巻くように、予め前記基部に一体形成されてなり、前記基部と前記板状部とが密着するように、前記位置決め部を前記位置決め孔並びに前記孔部に挿通させて前記接点保持部材が前記アームホルダに対し位置決め保持される構成としたことを特徴とする。
【００１５】
また本発明は、前記位置決め部とこれに対応する前記位置決め孔が少なくとも２組設けられ、前記各位置決め孔のうちの一方に前記筒状部を設け、前記筒状部が設けられない他方の前記位置決め孔を、前記一方の位置決め孔の方向に内径の大きい長孔に形成したことを特徴とする。
【００１６】
【発明の実施の形態】
本発明の液面検出装置１は、液面に浮くフロートを備えたフロートアーム２と、フロートアーム２を保持するアームホルダ３と、アームホルダ３を回動可能に備えた本体フレーム４と、本体フレーム４に固定される回路基板５と、回路基板５上を摺動する摺動接点６を有する接点保持部材７とを有し、アームホルダ３は、その板状部２９から突出形成された突起形状からなる位置決め部１６を備え、接点保持部材７は、その基部３２において、位置決め部１６に対応する箇所に貫通孔からなる位置決め孔２７を備え、接点保持部材７には、位置決め孔２７に位置決め部１６を挿通させる前の段階で、位置決め孔２７に連通する孔部を有する筒状部２８が、板状部２９側とは反対側となる基部３２の前面側において、位置決め孔２７を取り巻くように、予め基部３２に一体形成されてなり、基部３２と板状部２９とが密着するように、位置決め部１６を位置決め孔２７並びに前記孔部に挿通させて接点保持部材７がアームホルダ３に対し位置決め保持される構成としたものである。このように構成したことにより、アームホルダ３と接点保持部材７とのガタツキを抑制することができる。
【００１７】
また本発明の液面検出装置１は、液面に浮くフロートを備えたフロートアーム２と、フロートアーム２を保持するとともに回動支点に２つの軸部１４を備えたアームホルダ３と、アームホルダ３の軸部１４を各々軸支する２つの離間した軸受部１９，２０で回動可能に保持する本体フレーム４と、本体フレーム４に固定される回路基板５と、回路基板５上を摺動する摺動接点６を有する接点保持部材７とを有し、アームホルダ３は、その板状部２９から突出形成された突起形状からなる位置決め部１６を備え、接点保持部材７は、その基部３２において、位置決め部１６に対応する箇所に貫通孔からなる位置決め孔２７を備え、接点保持部材７には、位置決め孔２７に位置決め部１６を挿通させる前の段階で、位置決め孔２７に連通する孔部を有する筒状部２８が、板状部２９側とは反対側となる基部３２の前面側において、位置決め孔２７を取り巻くように、予め基部３２に一体形成されてなり、基部３２と板状部２９とが密着するように、位置決め部１６を位置決め孔２７並びに前記孔部に挿通させて接点保持部材７がアームホルダ３に対し位置決め保持される構成としたものである。このように構成したことにより、アームホルダ３と接点保持部材７とのガタツキを抑制することができる。
【００１８】
また本発明の液面検出装置１は、位置決め部１６とこれに対応する位置決め孔２７が少なくとも２組設けられ、２つの位置決め孔２７のうちの一方に筒状部２８を設け、筒状部２８が設けられない他方の位置決め孔２７を、一方の位置決め孔２７の方向に内径の大きい長孔に形成したことにより、長孔となる他方の位置決め孔２７で寸法公差や誤差を吸収でき、組み付け作業性を向上させることができる。
【００１９】
【実施例】
以下、図面を用いて本発明の実施例を説明する。図１から図４は、本発明の第１実施例を示すものである。
【００２０】
本発明を自動車等の車両の液面検出装置１に適用した例で説明を行うが、図７から図１０に示した従来例と共通部分には、同一符号を付してその詳細説明は省略し、以下、本発明の適用対象となるアームホルダと接点保持部材について詳細に説明する。
【００２１】
アームホルダ３は合成樹脂からなり、図１から図３に詳しく示すように所定方向に延びる板状部２９と、この板状部２９の端面で一体に形成され略Ｔ字状となるような胴部１３とが設けられている。この板状部２９の一方の面３０にはフロートアーム２の折り曲げた端部１０が貫通する孔１１を有する保持部１２を備えるとともに、フロートアーム２を両側から保持する保持片３ａを備えている。この保持部１２と保持片３ａとにより、フロートアーム２はアームホルダ３に位置決め固定されている。また、板状部２９の他方の面３１には後述する接点保持部材を位置決め保持する突起形状の位置決め部１６が胴部１３の近傍に２個設けられている。また、胴部１３を挟んで２つに位置的に離間した軸部１４を備え、この軸部１４はアームホルダ３において同一軸上両端に位置して形成されており、胴部１３と軸部１４とは、その中心部に貫通した孔１５を備えた筒状である。なお、この軸部１４はフロートアーム２の回動支点である。
【００２２】
接点保持部材７は金属材料からなる板材をプレス成形してなり、図３，図４に詳しく示すようにアームホルダ３の板状部２９の外形と略同等の形状を有しており、アームホルダ３の各位置決め部１６に対応する箇所に設けられ、位置決め部１６に挿入される２つの位置決め孔２７と、これら位置決め孔２７を含む基部３２から板状部２９に沿うように設けられ各々が摺動接点６を有するコの字状の第１，第２の弾性片３３，３４とを備えている。また、各位置決め孔２７の周縁には位置決め部１６に沿って延びる円筒状の筒状部２８が形成されている。この筒状部２８を形成することにより、位置決め孔２７のアームホルダ側開口端部には、末広がり状となる傾斜面２７ａが形成されている。
【００２３】
アームホルダ３と接点保持部材７との組み付けは、摺動接点６が回路基板５側を向くように位置させて、接点保持部材７の２つの位置決め孔２７をそれぞれアームホルダ３の２個の位置決め部１６に挿入することにより行われる。この際、位置決め部１６に対して、位置決め孔２７及びこの位置決め孔２７に連続する筒状部２８の内壁面が圧入状態で挿入され、これにより接点保持部材７がアームホルダ３に圧入保持される。
【００２４】
このように本実施例では、アームホルダ３の位置決め部１６に接点保持部材７の位置決め孔２７及び筒状部２８が圧入状態で挿入されることにより、位置決め部１６に対する接点保持部材７の接触面積を増加させることができ、接点保持部材７を確実に保持することができる。
【００２５】
また本実施例では、位置決め孔２７に末広がり状となる傾斜面２７ａが形成され、この傾斜面２７ａによって位置決め部１６を挿入案内できるため、組み付け作業性を向上させることができる。
【００２６】
また本実施例では、位置決め部１６と位置決め孔２７とが２組設けられ、各位置決め孔２７の双方に筒状部２８を設けたことにより、接点保持部材７をより確実に保持することができる。
【００２７】
図５は本発明の第２実施例を示しており、本実施例では、２組設けられる位置決め部１６と位置決め孔２７のうち、図中、左側に位置する組の一方の位置決め孔２７の周縁に筒状部２８を設け、右側に位置する組の他方の位置決め孔２７には筒状部２８を設けずに、その形状を長孔に設定したものである。すなわち、図中、右側に位置する他方の位置決め孔２７は、図中、左側に位置する一方の位置決め孔２７の方向に内径が大きく、この方向とは直交する方向に内径が小さい長孔に形成したもので、この長孔の径小となる方向の寸法Ｗ１は、位置決め部１６の外径に対応し、径大となる方向の寸法Ｗ２は、位置決め部１６の外径よりも大きく形成されている。このように構成したことにより、前記第１実施例と同様の効果を期待できると共に、長孔となる他方の位置決め孔２７で寸法公差や誤差を吸収でき、組み付け作業性を向上させることができる。
【００２８】
図６は本発明の第３実施例を示しており、本実施例では、２組設けられる位置決め部１６と位置決め孔２７のうち、図中、左側に位置する組の一方の位置決め孔２７の周縁に筒状部２８を設け、右側に位置する組の他方の位置決め孔２７には筒状部２８を設けず、この筒状部２８が設けられない位置決め孔２７に対応する位置決め部１６を溶着して接点保持部材７をアームホルダ３に位置決め保持したものである。このように構成したことによって、前記第１実施例と同様の効果を期待することができると共に、位置決め部１６を溶着することにより、接点保持部材７を確実に保持することができる。
【００２９】
なお、位置決め部１６と、これに対応する位置決め孔２７、及び筒状部２８は前記各実施例に限定されることはなく、アームホルダ３と接点保持部材７とのガタツキを抑制できる形状であればどのような形状を用いてもよい。
【００３０】
【発明の効果】
以上、本発明によれば、所期の目的を達成することができ、アームホルダと接点保持部材とのガタツキを抑制することが可能な液面検出装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の第１実施例の断面図
【図２】同実施例におけるアームホルダと接点保持部材の組付状態での側面図
【図３】同実施例におけるアームホルダと接点保持部材の組付状態図
【図４】図３中のＡ−Ａ断面図
【図５】本発明の第２実施例におけるアームホルダと接点保持部材の組付状態図
【図６】本発明の第３実施例におけるアームホルダと接点保持部材の組付状態での断面図
【図７】従来例の上面図
【図８】図７中のＢ−Ｂ線の断面図
【図９】従来例のアームホルダと接点保持部材の要部組付状態図
【図１０】図９中のＣ−Ｃ線の断面図
【符号の説明】
１液面検出装置
２フロートアーム
３アームホルダ
３ｂ熱溶着部
４本体フレーム
５回路基板
６摺動接点
７接点保持部材
１６位置決め部
２６貫通孔
２７位置決め孔
２７ａ傾斜面
２８筒状部
２９板状部
３０一方の面
３１他方の面
３２基部
３３第１の弾性片
３４第２の弾性片[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid level detection device, and more particularly to a liquid level detection device provided with a float.
[0002]
[Prior art]
As shown in FIGS. 7 to 10, the conventional liquid level detection device 1 moves, for example, with a float arm 2 interlocked with a float (not shown) that floats on the liquid level of a fuel tank (not shown), and with the rotation of the float arm 2. The arm holder 3, the main body frame 4 that pivotally supports the shaft portion 14 of the arm holder 3, a circuit board 5 fixed to the main body frame 4, and a sliding contact 6 that slides on the circuit board 5. A contact holding member 7 fixed to the arm holder 3, a terminal 8 electrically connected to the circuit board 5, and a lead wire 9 connecting the terminal 8 and an external circuit (not shown) Along with the float, the float arm 2 and the arm holder 3, the sliding contact 6 slides on the circuit board 5 to cause voltage fluctuations caused by a resistor (not shown) provided on the circuit board 5 by the lead wire 9. Illustrated And outputs to the absence of an external circuit is known.
[0003]
The float arm 2 is made of a metal rod, and has a float (not shown) that floats on the liquid surface at the tip. The other end 10 is bent.
[0004]
The arm holder 3 is made of synthetic resin, and includes a holding portion 12 having a hole 11 through which the bent end portion 10 of the float arm 2 passes, and a holding piece 3a for holding the float arm 2 from both sides. The float arm 2 is positioned and fixed to the arm holder 3 by the holding portion 12 and the holding piece 3a. Further, the arm holder 3 includes two shaft portions 14 that are positioned at two positions with the body portion 13 interposed therebetween. The shaft portions 14 are formed at both ends on the same axis in the arm holder 3. 13 and the axial part 14 are the cylinders provided with the hole 15 penetrated in the center part. Further, the arm holder 3 is formed with two positioning portions 16 for positioning a later-described contact holding member in the vicinity of the body portion 13.
[0005]
Further, the assembly of the float arm 2 to the arm holder 3 is performed by inserting the end 10 of the float arm 2 into the hole 11 of the holding part 12 and centering the axis of the end 10 held rotatably by the holding part 12. This is completed by rotating the shaft portion 14 in the axial direction and elastically deforming the holding piece 3a of the arm holder 3 to hold the float arm 2.
[0006]
The main body frame 4 is made of synthetic resin, and is composed of two frame components 17 and 18. In order to pivotally support the arm holder 3 so that the arm holder 3 can be pivoted, the frame constituting bodies 17 and 18 are provided with bearing portions 19 and 20 for receiving the shaft portion 14 of the arm holder 3.
[0007]
The frame constituting body 17 is provided with four elastic pieces having locking claws, and the other frame constituting body 18 is similarly provided with four locking portions with which the locking claws are engaged. . The frame structure 18 is formed with two pins 21 protruding, and the frame structure 17 is provided with a hole 22 through which the pin 21 passes. The frame components 17 and 18 are assembled and fixed by engaging the locking claws and the locking portions provided on the frame components 17 and 18, respectively, and thermally bonding the end portions of the pins 21 exposed from the holes 22. Complete by transforming.
[0008]
The frame structure 18 is provided with a cutout portion 23 in which a part thereof is cut out. The notch 23 constitutes the guide portion 24 in a state where the frame structure 17 and the frame structure 18 are assembled.
[0009]
The circuit board 5 is made of ceramic, and has a conductor 25 and a resistor (not shown) on its surface. The circuit board 5 is fixed to the frame structure 18.
[0010]
The contact holding member 7 is a metal thin plate, and is provided with a through hole 26 corresponding to the positioning portion 16 of the arm holder 3 and two sliding contacts 6 that slide on the circuit board 5. The sliding contact 6 is obtained by integrally forming a contact holding member 7 by, for example, pressing. The contact holding member 7 and the arm holder 3 are assembled by inserting the positioning portion 16 of the arm holder 3 into the through hole 26 of the contact holding member 7 so that the sliding contact 6 faces the circuit board 7 side. It is fixed by the heat welding part 3b which heat-welded the front-end | tip of the positioning part 16 exposed from.
[0011]
[Problems to be solved by the invention]
However, in the case of such a liquid level detection device 1, the through hole 26 of the contact holding member 7 and the positioning part 16 of the arm holder 3 are fixed by the heat welding part 3b. In the method, it is difficult to suppress the backlash on the dimensional tolerance between the through hole 26 and the positioning portion 16. That is, there is a concern that the sliding contact 6 may be displaced from the normal position due to the rattling and adversely affect the voltage fluctuation caused by the resistor (not shown) provided on the circuit board 5.
[0012]
The present invention has been made in view of this point, and a main object of the present invention is to provide a liquid level detection device capable of suppressing backlash between an arm holder and a contact holding member.
[0013]
[Means for Solving the Problems]
To achieve the above object, the present invention provides a float arm including a float that floats on a liquid surface, an arm holder that holds the float arm, a main body frame that rotatably includes the arm holder, and the main body A positioning portion having a circuit board fixed to the frame and a contact holding member having a sliding contact sliding on the circuit board, the arm holder having a protruding shape formed protruding from the plate-like portion The contact holding member includes a positioning hole formed of a through hole at a position corresponding to the positioning portion at a base portion thereof, and the contact holding member has a stage before the positioning portion is inserted into the positioning hole. Thus, the cylindrical part having a hole communicating with the positioning hole surrounds the positioning hole on the front side of the base part which is opposite to the plate-like part side. Therefore, the contact holding member is positioned with respect to the arm holder by inserting the positioning portion into the positioning hole and the hole so that the base and the plate-like portion are in close contact with each other. It is characterized by having a configuration to be held .
[0014]
The present invention also provides a float arm having a float that floats on a liquid surface, an arm holder that holds the float arm and has two shaft portions at a pivot point, and a shaft portion of the arm holder. has a body frame rotatably held by two spaced bearing portions, and a circuit board fixed to the body frame, and a contact holding member having a sliding contact which slides the circuit on the substrate, wherein The arm holder includes a positioning portion made of a protrusion formed to protrude from the plate-like portion, and the contact holding member includes a positioning hole made of a through hole at a location corresponding to the positioning portion at the base portion, In the contact holding member, before the positioning portion is inserted into the positioning hole, the cylindrical portion having a hole communicating with the positioning hole is on the side opposite to the plate-like portion side. On the front side of the base portion, the base portion is integrally formed in advance so as to surround the positioning hole, and the base portion and the plate-like portion are in close contact with each other so that the positioning portion is placed on the positioning hole and the hole portion. The contact holding member is positioned and held with respect to the arm holder by being inserted therethrough .
[0015]
In the present invention, at least two sets of the positioning portion and the corresponding positioning holes are provided, the cylindrical portion is provided in one of the positioning holes, and the other of the positioning portions is not provided. The positioning hole is a long hole having a large inner diameter in the direction of the one positioning hole.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
A liquid level detection apparatus 1 according to the present invention includes a float arm 2 having a float that floats on the liquid level, an arm holder 3 that holds the float arm 2, a main body frame 4 that is rotatably provided with the arm holder 3, and a main body. The arm holder 3 includes a circuit board 5 fixed to the frame 4 and a contact holding member 7 having a sliding contact 6 that slides on the circuit board 5. The contact holding member 7 includes a positioning hole 27 including a through hole at a position corresponding to the positioning portion 16 in the base portion 32, and the contact holding member 7 is positioned in the positioning hole 27. Before the portion 16 is inserted, the cylindrical portion 28 having a hole communicating with the positioning hole 27 surrounds the positioning hole 27 on the front surface side of the base portion 32 opposite to the plate-like portion 29 side. In this way, the contact holding member 7 is attached to the arm holder 3 by forming the positioning portion 16 through the positioning hole 27 and the hole portion so that the base portion 32 and the plate-like portion 29 are in close contact with each other. In contrast, it is configured to be positioned and held . With such a configuration, it is possible to suppress backlash between the arm holder 3 and the contact holding member 7.
[0017]
The liquid level detection device 1 according to the present invention includes a float arm 2 having a float that floats on the liquid level, an arm holder 3 that holds the float arm 2 and includes two shaft portions 14 at a rotation fulcrum, and an arm holder. The main body frame 4 rotatably held by two spaced apart bearing portions 19 and 20 that respectively support the three shaft portions 14, the circuit board 5 fixed to the main body frame 4, and sliding on the circuit board 5 The arm holder 3 includes a positioning portion 16 having a protruding shape protruding from the plate-like portion 29, and the contact holding member 7 has a base portion 32. 3, a positioning hole 27 including a through hole is provided at a location corresponding to the positioning portion 16, and the contact holding member 7 has a hole portion communicating with the positioning hole 27 before the positioning portion 16 is inserted into the positioning hole 27. The cylindrical portion 28 is integrally formed in advance with the base portion 32 so as to surround the positioning hole 27 on the front side of the base portion 32 opposite to the plate-like portion 29 side. The contact holding member 7 is positioned and held with respect to the arm holder 3 by inserting the positioning portion 16 through the positioning hole 27 and the hole portion so that the contact holding member 7 is in close contact with the arm holder 3 . With such a configuration, it is possible to suppress backlash between the arm holder 3 and the contact holding member 7.
[0018]
In the liquid level detection device 1 of the present invention, at least two sets of positioning portions 16 and corresponding positioning holes 27 are provided, and a cylindrical portion 28 is provided in one of the two positioning holes 27. By forming the other positioning hole 27 not provided with a long hole having a large inner diameter in the direction of the one positioning hole 27, the other positioning hole 27 serving as the long hole can absorb dimensional tolerances and errors, and the assembling work Can be improved.
[0019]
【Example】
Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment of the present invention.
[0020]
The present invention will be described with reference to an example in which the present invention is applied to a liquid level detecting device 1 for a vehicle such as an automobile. However, the same reference numerals are given to common parts with the conventional examples shown in FIGS. Hereinafter, the arm holder and the contact holding member to which the present invention is applied will be described in detail.
[0021]
The arm holder 3 is made of a synthetic resin, and as shown in detail in FIGS. 1 to 3, a plate-like portion 29 extending in a predetermined direction and a body that is formed integrally with the end face of the plate-like portion 29 and has a substantially T-shape. Part 13 is provided. One surface 30 of the plate-like portion 29 includes a holding portion 12 having a hole 11 through which the bent end portion 10 of the float arm 2 passes, and a holding piece 3a for holding the float arm 2 from both sides. . The float arm 2 is positioned and fixed to the arm holder 3 by the holding portion 12 and the holding piece 3a. Further, on the other surface 31 of the plate-like portion 29, two protrusion-shaped positioning portions 16 for positioning and holding a contact holding member described later are provided in the vicinity of the body portion 13. In addition, two shaft portions 14 are provided that are spaced apart from each other by sandwiching the body portion 13. The shaft portions 14 are formed at both ends on the same axis in the arm holder 3. 14 is a cylindrical shape provided with a hole 15 penetrating through the center thereof. The shaft portion 14 is a rotation fulcrum of the float arm 2.
[0022]
The contact holding member 7 is formed by press-molding a plate material made of a metal material, and has a shape substantially equivalent to the outer shape of the plate-like portion 29 of the arm holder 3 as shown in detail in FIGS. Are provided at locations corresponding to the three positioning portions 16, and are provided so as to extend along the plate-like portion 29 from the two positioning holes 27 inserted into the positioning portion 16 and the base portion 32 including these positioning holes 27. U-shaped first and second elastic pieces 33 and 34 having a moving contact 6 are provided. Moreover, a circular cylindrical tubular portion 28 which Ru extending along the positioning portion 16 is formed in the periphery of the positioning holes 27. By forming the cylindrical portion 28, an inclined surface 27 a is formed at the opening end of the positioning hole 27 on the arm holder side so as to be divergent.
[0023]
The arm holder 3 and the contact holding member 7 are assembled by positioning the sliding contact 6 so as to face the circuit board 5, and positioning the two positioning holes 27 of the contact holding member 7 with the two positioning holes of the arm holder 3. This is done by inserting it into the section 16. At this time, the positioning hole 27 and the inner wall surface of the cylindrical portion 28 continuing to the positioning hole 27 are inserted into the positioning portion 16 in a press-fitted state, whereby the contact holding member 7 is press-fitted and held in the arm holder 3. .
[0024]
Thus, in the present embodiment, the contact hole of the contact holding member 7 with respect to the positioning portion 16 is inserted into the positioning portion 16 of the arm holder 3 by inserting the positioning hole 27 and the cylindrical portion 28 of the contact holding member 7 in a press-fitted state. The contact holding member 7 can be reliably held.
[0025]
In the present embodiment, the positioning hole 27 is formed with an inclined surface 27a having a divergent shape, and the positioning portion 16 can be inserted and guided by the inclined surface 27a, so that the assembly workability can be improved.
[0026]
In the present embodiment, two sets of the positioning portion 16 and the positioning hole 27 are provided, and the cylindrical portion 28 is provided in both of the positioning holes 27, so that the contact holding member 7 can be held more reliably. .
[0027]
FIG. 5 shows a second embodiment of the present invention. In this embodiment, of the positioning portions 16 and the positioning holes 27 provided in two sets, the peripheral edge of one positioning hole 27 of the set located on the left side in the drawing. A cylindrical portion 28 is provided on the other side, and the other positioning hole 27 of the set located on the right side is not provided with the cylindrical portion 28 and the shape thereof is set as a long hole. That is, the other positioning hole 27 located on the right side in the figure is formed as a long hole having a large inner diameter in the direction of one positioning hole 27 located on the left side in the figure and a small inner diameter in a direction perpendicular to this direction. Thus, the dimension W1 in the direction of decreasing the diameter of the long hole corresponds to the outer diameter of the positioning part 16, and the dimension W2 in the direction of increasing the diameter is formed larger than the outer diameter of the positioning part 16. Yes. With this configuration, the same effect as that of the first embodiment can be expected, and the other positioning hole 27 that is a long hole can absorb dimensional tolerances and errors, thereby improving the assembling workability.
[0028]
FIG. 6 shows a third embodiment of the present invention. In this embodiment, of the positioning portions 16 and the positioning holes 27 provided in two sets, the peripheral edge of one positioning hole 27 of the set located on the left side in the drawing. The cylindrical portion 28 is provided on the other side, and the other positioning hole 27 of the set located on the right side is not provided with the cylindrical portion 28, and the positioning portion 16 corresponding to the positioning hole 27 where the cylindrical portion 28 is not provided is welded. The contact holding member 7 is positioned and held on the arm holder 3. With this configuration, the same effect as in the first embodiment can be expected, and the contact holding member 7 can be reliably held by welding the positioning portion 16.
[0029]
Note that the positioning portion 16, the corresponding positioning hole 27, and the cylindrical portion 28 are not limited to the above-described embodiments, and may have a shape that can suppress backlash between the arm holder 3 and the contact holding member 7. Any shape may be used.
[0030]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a liquid level detection device that can achieve an intended purpose and can suppress backlash between the arm holder and the contact holding member.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a first embodiment of the present invention. FIG. 2 is a side view of the arm holder and contact holding member assembled in the embodiment. FIG. 3 is an arm holder and contact holding member in the embodiment. FIG. 4 is a sectional view taken along the line AA in FIG. 3. FIG. 5 is an assembled state diagram of the arm holder and the contact holding member in the second embodiment of the present invention. FIG. 7 is a top view of a conventional example. FIG. 8 is a cross-sectional view taken along the line BB in FIG. 7. FIG. 9 is a conventional arm holder. Fig. 10 is a sectional view taken along line CC in Fig. 9 [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Liquid level detection apparatus 2 Float arm 3 Arm holder 3b Thermal welding part 4 Main body frame 5 Circuit board 6 Sliding contact 7 Contact holding member 16 Positioning part 26 Through-hole 27 Positioning hole 27a Inclined surface 28 Cylindrical part 29 Plate-like part 30 One surface 31 The other surface 32 Base 33 First elastic piece 34 Second elastic piece

Claims

A float arm having a float that floats on a liquid surface, an arm holder that holds the float arm, a main body frame that is capable of rotating the arm holder, a circuit board that is fixed to the main body frame, and the circuit board A contact holding member having a sliding contact sliding on the top,
The arm holder includes a positioning portion having a protruding shape that protrudes from the plate-shaped portion,
The contact holding member includes a positioning hole including a through hole at a position corresponding to the positioning portion at a base portion thereof.
In the contact holding member, the base portion having a cylindrical portion having a hole portion communicating with the positioning hole at a stage before the positioning portion is inserted into the positioning hole is opposite to the plate-like portion side. Is formed integrally with the base in advance so as to surround the positioning hole,
The contact holding member is positioned and held with respect to the arm holder by inserting the positioning portion into the positioning hole and the hole so that the base portion and the plate-like portion are in close contact with each other. Liquid level detection device.

A float arm having a float that floats on the liquid surface, an arm holder that holds the float arm and has two shaft portions at a pivotal fulcrum, and two spaced bearings that respectively support the shaft portions of the arm holder A main body frame that is rotatably held by a portion, a circuit board fixed to the main body frame, and a contact holding member having a sliding contact that slides on the circuit board,
The arm holder includes a positioning portion having a protruding shape that protrudes from the plate-shaped portion,
The contact holding member includes a positioning hole including a through hole at a position corresponding to the positioning portion at a base portion thereof.
In the contact holding member, the base portion having a cylindrical portion having a hole portion communicating with the positioning hole at a stage before the positioning portion is inserted into the positioning hole is opposite to the plate-like portion side. Is formed integrally with the base in advance so as to surround the positioning hole,
The contact holding member is positioned and held with respect to the arm holder by inserting the positioning portion into the positioning hole and the hole so that the base portion and the plate-like portion are in close contact with each other. Liquid level detection device.

At least two sets of the positioning portion and the corresponding positioning holes are provided, the cylindrical portion is provided in one of the positioning holes, and the other positioning hole in which the cylindrical portion is not provided, 3. The liquid level detection device according to claim 1, wherein the liquid level detection device is formed as a long hole having a large inner diameter in the direction of one positioning hole.