JP3773048B2

JP3773048B2 - Liquid leak amount measuring apparatus and liquid leak amount measuring method

Info

Publication number: JP3773048B2
Application number: JP2002203796A
Authority: JP
Inventors: 隆義相良; 健次飯田; 知幸関角; 真山口
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2002-07-12
Filing date: 2002-07-12
Publication date: 2006-05-10
Anticipated expiration: 2022-07-12
Also published as: JP2004045249A

Description

【０００１】
【発明の属する技術分野】
本発明は、液体を収容する被測定物からの液漏れ量を測定する装置並びに方法に関する。
【０００２】
【従来の技術】
従来、液体を収容する被測定物からの液漏れ量を測定する装置が各種提案されている。液漏れ量測定装置の一種に、被測定物の測定対象箇所から漏れた液体が流入可能にその測定対象箇所に接続される通路部と、上端部側が大気開放され下端部側が通路部に接続されて通路部内の液体が管内に流入する測定管とを備えた装置が知られている。この装置では、被測定物からの液漏れにより測定管内の液面高さが上昇するようになっており、その液面高さの基準高さからの上昇量に基づいて液漏れ量を測定している。
【０００３】
【発明が解決しようとする課題】
上記測定管を用いる液漏れ量測定装置では、一測定で測定管内の液面高さが上昇した後に、連続して次の測定を行う場合には、測定管内の液面高さを基準高さに戻す。しかし、先の測定において液面高さの上昇量が大きいと、その液面上昇により濡れる測定管内壁の面積が管軸方向に拡大するため、次の測定開始時になっても管内壁の基準高さよりも上側部分に液体が多量に残存してしまう。この残存液体は、次の測定中に重力降下して液面高さを変化させるため、測定精度の悪化の要因となっている。尤も、先の測定終了時から次の測定開始時までに残存液体を降下させるための時間を長くとれば測定精度は向上するが、その分、測定効率の低下は否めない。
本発明の目的は、被測定物からの液漏れ量を高精度に且つ効率良く測定できる液漏れ量測定装置並びに測定方法を提供することにある。
【０００４】
【課題を解決するための手段】
本発明の請求項１に記載の液漏れ量測定装置及び請求項３に記載の液漏れ量測定方法によると、被測定物からの液漏れにより測定管内の液面高さが上昇し所定高さに達したとき、通路部及び測定管内に導入する導入液体の容積を減容して測定管内の液面高さを降下させる。それにより、一測定時において液漏れによる液面高さの上昇量を制限できるので、その液面上昇により濡れる測定管内壁の面積が管軸方向に拡大することを抑制できる。そのため、次の測定時に液面高さを戻すようにしても、その戻し先の液面高さよりも上側において測定管内壁に残存付着する液体を短時間で降下させることができる。したがって、先の測定終了時から次の測定開始時までの時間間隔を短縮しても、次の測定までに液面高さを充分に安定させることができる。
【０００５】
さらに請求項１に記載の液漏れ量測定装置及び請求項３に記載の液漏れ量測定方法によると、測定管内の液面高さの推移に基づき被測定物からの液漏れ量を算定するので、液面高さを降下させたことによる影響を考慮して液漏れ量を精確に求めることができる。
このように請求項１に記載の液漏れ量測定装置及び請求項３に記載の液漏れ量測定方法によれば、被測定物からの液漏れ量を高精度に且つ効率良く測定することができる。
【０００６】
本発明の請求項２に記載の液漏れ量測定装置及び請求項４に記載の液漏れ量測定方法によると、液漏れ量は、測定終了時の液面高さの上昇分に相当する液体容積と、測定時間内における導入液体の総減容容積との和により求められる。これにより、液漏れ量を比較的簡単な演算で且つ精確に求めることができる。
【０００７】
【発明の実施の形態】
以下、本発明の実施の形態を示す一実施例を図面に基づいて説明する。
本発明の一実施例による液漏れ量測定装置を図１に示す。液漏れ量測定装置１０は、液体を収容する被測定物２からの液漏れ量を測定する。本実施例における被測定物２は、内燃機関用の燃料噴射装置である。この燃料噴射装置２は、一端部の流入口４から流入し内部に収容した燃料を開弁作用により他端部の噴射口６から噴射する。燃料噴射装置２については、閉弁状態での噴射口６からの液漏れ量が測定対象であり、噴射口６が測定対象箇所である。
【０００８】
保持部１１は、クランプ装置１２、駆動装置１４等を有する。クランプ装置１２は、噴射口６が鉛直方向下側を向くように燃料噴射装置２を保持する。クランプ装置１２に保持された燃料噴射装置２の流入口４には、図示しないポンプから液体としての測定油が供給管１３を通じて所定の油圧で供給される。これにより、測定油が閉弁状態の燃料噴射装置２内に収容される。駆動装置１４は、駆動源１５の回転駆動力をプーリ１６，１７及びベルト１８を介して運動変換機構１９に伝達し、その運動変換機構１９で回転駆動力を変換して得た直線駆動力をクランプ装置１２に伝達する。この駆動力伝達によりクランプ装置１２は鉛直方向両側に移動可能である。
【０００９】
通路部２０は、測定油が導入される接続通路２１を有する。本実施例の接続通路２１は概ねＵ字状に形成され、両端部２１ａ，２１ｂが鉛直方向上側に向かって延伸している。通路部２０は、接続通路２１の一端部２１ａ側に接続凹部２２を有する。この接続凹部２２には、クランプ装置１２に保持された燃料噴射装置２の噴射口６が挿入されＯリング（図示しない）を介して接続される。この接続状態では、燃料噴射装置２の噴射口６から液漏れがあると、その漏れた測定油が接続通路２１内に流入する。
【００１０】
測定管２４は、外部から内部が視認可能な例えばガラス管で形成されている。測定管２４は、概ね鉛直方向に延伸するように通路部２０上に固設されている。測定管２４の上端部２４ａは大気開放され、測定管２４の下端部２４ｂは接続通路２１の他端部２１ｂに接続されている。測定管２４内には、それと連通する接続通路２１内の測定油が下端部２４ｂ側から毛管現象により流入する。
【００１１】
検出部２６は測定管２４の外周側に配設され、測定管２４内の測定油と大気との境界面である液面Ｓの高さを検出する。ここで液面Ｓの高さとは、測定管２４内において液面Ｓが定位する管軸方向の位置を意味する。本実施例では、管軸方向の所定の中間位置Ｈ₀（図２参照）を基準高さＨ₀として設定し、その基準高さＨ₀を含む管軸方向の所定範囲内を検出部２６で検出する。検出部２６には図１に示すようなＣＣＤカメラを用いるが、レーザー変位計や光学式変位計を用いてもよい。
【００１２】
調整部２８は、マイクロシリンジ２９、駆動源３２、運動変換機構３３等を有する。
マイクロシリンジ２９は、段付円筒形状のシリンダ３０内に測定油を収容可能である。シリンダ３０のうち小径の先端部３０ａは通路部２０に液密に嵌入され、接続通路２１に接続されている。これにより、シリンダ３０内と接続通路２１内とが連通している。シリンダ３０の反先端部側にピストン３１が液密に往復移動自在に挿入されている。駆動源３２はサーボモータ等で構成され、回転駆動力を運動変換機構３３に伝達する。運動変換機構３３は、伝達された回転駆動力を直線駆動力に変換してピストン３１に伝達する。
【００１３】
駆動源３２の順回転作動によりピストン３１がシリンダ３０の反先端部側に移動するとき、接続通路２１内の測定油がシリンダ３０内に吸入され、接続通路２１及び測定管２４内に導入される測定油の総容積（以下、導入油容積という）が減容する。一方、駆動源３２の逆回転作動によりピストン３１がシリンダ３０の先端部側に移動するとき、シリンダ３０内の測定油が接続通路２１内に吐出され、導入油容積が増大する。
【００１４】
制御部３６はマイクロコンピュータを主体に構成されている。制御部３６は、検出部２６、調整部２８の駆動源３２等に図示しないドライバを介して電気的に接続されている。制御部３６は、検出部２６が検出した液面高さを表す信号を検出部２６から受け取り、その信号に基づいて調整部２８（駆動源３２）の作動を制御すると共に燃料噴射装置２からの液漏れ量を算定する。
【００１５】
ここで、制御部３６による調整部２８の作動制御方法について説明する。
通路部２０に接続された燃料噴射装置２について測定を開始するに先立ち、制御部３６は調整部２８を制御して導入油容積を調整する。このとき導入油容積は、図２（Ａ）に示すように測定管２４内の液面Ｓの高さが基準高さＨ₀に精確に一致するように調整される。
【００１６】
液漏れ量測定装置１０では、通路部２０に接続された燃料噴射装置２に液漏れが生じると、その漏れた測定油が通路部２０の接続通路２１内に流入し、図２（Ｂ）に白抜き矢印で示すように測定管２４内で液面Ｓの高さが上昇する。制御部３６は、検出部２６から送出される信号に基づき、図３に示すような液面高さの推移を監視する。そして液面上昇の結果、図２（Ｂ）及び図３に示す如く基準高さＨ₀から所定距離離れた上限高さＨ_maxに液面高さが達すると、制御部３６は調整部２８を制御して導入油容積を減容する。このとき導入油容積は、図２（Ｃ）及び図３に示すように液面高さが基準高さＨ₀にまで降下するように減容される。尚、図４に示すように予め定められた測定時間Ｔ内では、液面高さが上限高さＨ_maxに到達する度に導入油容積を減容し液面高さを降下させる。また上限高さＨ_maxについては、液面高さの降下後において基準高さＨ₀よりも上側で測定管２４の内壁に付着する残存油が少なくなるように可及的に小さく設定される。
【００１７】
次に、制御部３６による液漏れ量の算定方法について説明する。
制御部３６では、測定管２４内の液面高さの推移に基づいて液漏れ量を算定する。具体的には、液面高さの推移を反映する二つの物理量Ｖ₁，Ｖ₂の和により液漏れ量を求める。ここで一方の物理量Ｖ₁は、図５に示すように、測定終了時ｔ_eの液面高さの上昇分ΔＨ（図４参照）に相当する液体容積であり、例えば液面高さの上昇量ΔＨと測定管２４の横断面積との積により算出することができる。また、他方の物理量Ｖ₂は、図５に示すように、測定時間Ｔ内における導入油の総減容容積であり、例えばピストン３１（シリンダ３０）の横断面積と測定時間Ｔ内におけるピストン３１の移動量との積により算出することができる。
以上本実施例では、検出部２６及び制御部３６が共同して制御手段を構成し、制御部３６が演算手段を構成している。
【００１８】
以下、上述した液漏れ量測定装置１０を用いて燃料噴射装置２からの液漏れ量を測定する方法について説明する。
（１）保持部１１のクランプ装置１２に燃料噴射装置２を保持させた後、クランプ装置１２を通路部２０側に接近移動させて、燃料噴射装置２の噴射口６を通路部２０の接続凹部２２に接続する。
（２）燃料噴射装置２内に測定油を供給管１３を通じて供給する。
【００１９】
（３）制御部３６により調整部２８を制御して導入油容積を調整することで、測定管２４内の液面高さを基準高さＨ₀に精確に一致させる。
（４）液漏れ量の測定を開始する。
（５）制御部３６により測定管２４内の液面高さを監視しつつ、液面高さが上限高さＨ_maxに到達した場合には、制御部３６により調整部２８を制御して導入油容積を減容し液面高さを基準高さＨ₀に戻す。
（６）測定が終了したら、燃料噴射装置２からの液漏れ量を算定する。さらに、測定管２４内の液面高さが基準高さＨ₀よりも上昇している場合には、次の測定に向けて、図示しないドレイン口から接続通路２１内の測定油を排出することで、液面高さを基準高さＨ₀に戻す。
【００２０】
以上説明した液漏れ量測定装置１０では、一測定時において測定管２４内の液面高さが上限高さＨ_maxに達すると液面高さが降下されるので、液面上昇により濡れる管内壁の面積は管軸方向に大きく拡大しない。そのため、上記（６）で液面高さを基準高さＨ₀に戻す際に、基準高さＨ₀よりも上側において管内壁に付着している残存油を短時間で降下させることができる。よって、先の測定終了時から次の測定開始時までの時間間隔が短くても、次の測定までに液面高さを充分に安定させることができる。
【００２１】
さらに液漏れ量測定装置１０では、測定管２４内の液面高さの推移を反映する上記二つの物理量Ｖ₁，Ｖ₂の和により液漏れ量を求めるので、比較的簡素な演算により液漏れ量を精確に算定することができる。
このように液漏れ量測定装置１０によれば、燃料噴射装置２からの液漏れ量を高精度に且つ効率良く測定することが可能である。
【００２２】
尚、上記実施例では、測定管２４内の液面高さが所定の上限高さＨ_maxに達した場合に、その液面高さを測定開始時の基準高さＨ₀にまで降下させたが、基準高さＨ₀と上限高さＨ_maxとの間の高さに降下させるようにしてもよい。また上記実施例では、被測定部物である燃料噴射装置２からの液漏れ量について、測定終了時ｔ_eの液面高さの上昇分ΔＨに相当する液体容積Ｖ₁と、測定時間Ｔ内における導入油の総減容容積Ｖ₂との和（Ｖ₁＋Ｖ₂）により求めた。これに対し、演算をより簡素化するために、液面高さのみに基づいて液漏れ量を求めるようにしてもよい。具体的には、図６に示すように、降下直前の液面高さの上昇分に相当する液体容積Ｖ₁₁，Ｖ₁₂と、測定終了時ｔ_eの液面高さの上昇分に相当する液体容積Ｖ₁₃との総和により液漏れ量を算出することが可能である。
【００２３】
さらに上記実施例では、測定管２４について鉛直方向に延伸するように配設したが、管軸方向の液面高さを検出可能であれば、鉛直方向の軸線に対して傾斜するように測定管２４を配設してもよい。
さらにまた、上記実施例では燃料噴射装置２を被測定物として扱ったが、液体を液密に収容可能な物品であれば本発明の被測定物となり得る。
【図面の簡単な説明】
【図１】本発明の一実施例による液漏れ量測定装置を示す模式図である。
【図２】図１に示す液漏れ量測定装置の作動を説明するための模式図である。
【図３】図１に示す液漏れ量測定装置の作動を説明するための特性図である。
【図４】図１に示す液漏れ量測定装置の作動を説明するための別の特性図である。
【図５】図１に示す液漏れ量測定装置において液漏れ量を算定する方法を説明するための特性図である。
【図６】図１に示す液漏れ量測定装置において液漏れ量を算定する別の方法を説明するための特性図である。
【符号の説明】
２燃料噴射装置（被測定物）
１０液漏れ量測定装置
１１保持部
２０通路部
２１接続通路
２４測定管
２６検出部（制御手段）
２８調整部
３６制御部（制御手段、演算手段）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and method for measuring the amount of liquid leakage from a measurement object that contains liquid.
[0002]
[Prior art]
Conventionally, various devices for measuring the amount of liquid leakage from an object to be measured containing liquid have been proposed. A kind of liquid leakage measuring device is connected to a passage portion connected to the measurement target portion so that liquid leaked from the measurement target portion of the object to be measured can flow in, and the upper end side is opened to the atmosphere and the lower end side is connected to the passage portion. An apparatus having a measuring tube through which liquid in the passage portion flows into the tube is known. In this device, the liquid level in the measuring tube rises due to liquid leakage from the object to be measured, and the amount of liquid leakage is measured based on the amount of rise from the reference height of the liquid level. ing.
[0003]
[Problems to be solved by the invention]
In the liquid leak amount measuring apparatus using the above measuring tube, the liquid level height in the measuring tube is used as the reference height when the next measurement is continuously performed after the liquid level height in the measuring tube has increased in one measurement. Return to. However, if the rise in the liquid level is large in the previous measurement, the area of the inner wall of the measurement tube that gets wet due to the rise in the liquid level expands in the direction of the pipe axis. A large amount of liquid remains in the upper part. This remaining liquid is lowered in gravity during the next measurement and changes the liquid level, which causes deterioration in measurement accuracy. However, if the time for lowering the remaining liquid is increased from the end of the previous measurement to the start of the next measurement, the measurement accuracy is improved, but the measurement efficiency is inevitably lowered accordingly.
An object of the present invention is to provide a liquid leakage amount measuring apparatus and a measuring method capable of measuring a liquid leakage amount from a measurement object with high accuracy and efficiency.
[0004]
[Means for Solving the Problems]
According to the liquid leak amount measuring apparatus of the first aspect of the present invention and the liquid leak amount measuring method of the third aspect of the present invention, the liquid level in the measuring tube increases due to the liquid leak from the object to be measured, and the predetermined height. Is reached, the volume of the introduced liquid introduced into the passage portion and the measuring tube is reduced to lower the liquid level in the measuring tube. Thereby, since the amount of increase in the liquid level due to liquid leakage can be limited during one measurement, it is possible to suppress the area of the inner wall of the measurement tube wetted by the liquid level from increasing in the tube axis direction. Therefore, even if the liquid level is returned at the time of the next measurement, the liquid remaining on the inner wall of the measuring tube can be lowered in a short time above the liquid level at the return destination. Therefore, even if the time interval from the end of the previous measurement to the start of the next measurement is shortened, the liquid level can be sufficiently stabilized by the next measurement.
[0005]
Furthermore, according to the liquid leak amount measuring device according to claim 1 and the liquid leak amount measuring method according to claim 3, the amount of liquid leak from the object to be measured is calculated based on the transition of the liquid level in the measuring tube. The amount of liquid leakage can be accurately determined in consideration of the effect of lowering the liquid level.
Thus, according to the liquid leak amount measuring apparatus according to claim 1 and the liquid leak amount measuring method according to claim 3, the liquid leak amount from the object to be measured can be measured with high accuracy and efficiency. .
[0006]
According to the liquid leakage amount measuring apparatus according to claim 2 of the present invention and the liquid leakage amount measuring method according to claim 4, the liquid leakage amount is a liquid volume corresponding to an increase in the liquid level at the end of the measurement. And the total volume reduction volume of the introduced liquid within the measurement time. Thereby, the amount of liquid leakage can be calculated | required accurately with comparatively simple calculation.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example showing an embodiment of the present invention will be described with reference to the drawings.
A liquid leakage amount measuring apparatus according to an embodiment of the present invention is shown in FIG. The liquid leak amount measuring apparatus 10 measures the liquid leak amount from the measurement object 2 that contains the liquid. The device under test 2 in the present embodiment is a fuel injection device for an internal combustion engine. The fuel injection device 2 injects the fuel that flows in from the inlet 4 at one end and is contained therein from the injection port 6 at the other end by a valve opening action. About the fuel injection device 2, the amount of liquid leakage from the injection port 6 in the valve-closed state is a measurement target, and the injection port 6 is a measurement target location.
[0008]
The holding unit 11 includes a clamp device 12, a drive device 14, and the like. The clamp device 12 holds the fuel injection device 2 so that the injection port 6 faces downward in the vertical direction. Measurement oil as a liquid is supplied from a pump (not shown) to the inlet 4 of the fuel injection device 2 held by the clamp device 12 through a supply pipe 13 at a predetermined hydraulic pressure. Thereby, measurement oil is accommodated in the fuel-injection apparatus 2 of a valve closing state. The driving device 14 transmits the rotational driving force of the driving source 15 to the motion conversion mechanism 19 via the pulleys 16, 17 and the belt 18, and the linear driving force obtained by converting the rotational driving force by the motion conversion mechanism 19 is obtained. This is transmitted to the clamping device 12. With this driving force transmission, the clamping device 12 can move to both sides in the vertical direction.
[0009]
The passage portion 20 has a connection passage 21 into which measurement oil is introduced. The connection passage 21 of this embodiment is generally U-shaped, and both end portions 21a and 21b extend upward in the vertical direction. The passage portion 20 has a connection recess 22 on the one end 21 a side of the connection passage 21. The injection recess 6 of the fuel injection device 2 held by the clamp device 12 is inserted into the connection recess 22 and connected through an O-ring (not shown). In this connected state, if there is a liquid leak from the injection port 6 of the fuel injection device 2, the leaked measurement oil flows into the connection passage 21.
[0010]
The measurement tube 24 is formed of, for example, a glass tube whose inside is visible from the outside. The measuring tube 24 is fixed on the passage portion 20 so as to extend substantially in the vertical direction. The upper end 24 a of the measurement tube 24 is open to the atmosphere, and the lower end 24 b of the measurement tube 24 is connected to the other end 21 b of the connection passage 21. The measurement oil in the connection passage 21 communicating with the measurement pipe 24 flows into the measurement pipe 24 from the lower end portion 24b side by capillary action.
[0011]
The detection unit 26 is disposed on the outer peripheral side of the measurement tube 24 and detects the height of the liquid level S that is a boundary surface between the measurement oil and the atmosphere in the measurement tube 24. Here, the height of the liquid surface S means a position in the tube axis direction where the liquid surface S is localized in the measurement tube 24. In this embodiment, the predetermined intermediate position H ₀ of the tube axis direction (see FIG. 2) is set as the reference height H _0, the detection unit 26 within a predetermined range in the tube axis direction including the reference height H ₀ To detect. Although the CCD camera as shown in FIG. 1 is used for the detection unit 26, a laser displacement meter or an optical displacement meter may be used.
[0012]
The adjustment unit 28 includes a microsyringe 29, a drive source 32, a motion conversion mechanism 33, and the like.
The microsyringe 29 can accommodate measurement oil in a cylinder 30 having a stepped cylindrical shape. A small-diameter tip portion 30 a of the cylinder 30 is fitted in the passage portion 20 in a liquid-tight manner and connected to the connection passage 21. Thereby, the inside of the cylinder 30 and the inside of the connection passage 21 communicate. A piston 31 is inserted in a liquid-tight manner on the opposite end side of the cylinder 30 so as to be reciprocally movable. The drive source 32 is constituted by a servo motor or the like, and transmits a rotational drive force to the motion conversion mechanism 33. The motion conversion mechanism 33 converts the transmitted rotational driving force into a linear driving force and transmits it to the piston 31.
[0013]
When the piston 31 moves to the opposite end side of the cylinder 30 by the forward rotation operation of the drive source 32, the measurement oil in the connection passage 21 is sucked into the cylinder 30 and introduced into the connection passage 21 and the measurement pipe 24. The total volume of the measured oil (hereinafter referred to as the introduced oil volume) is reduced. On the other hand, when the piston 31 moves to the tip end side of the cylinder 30 by the reverse rotation operation of the drive source 32, the measurement oil in the cylinder 30 is discharged into the connection passage 21, and the introduced oil volume increases.
[0014]
The control unit 36 is mainly composed of a microcomputer. The control unit 36 is electrically connected to the detection unit 26, the drive source 32 of the adjustment unit 28, and the like via a driver (not shown). The control unit 36 receives a signal representing the liquid level detected by the detection unit 26 from the detection unit 26, controls the operation of the adjustment unit 28 (drive source 32) based on the signal, and outputs from the fuel injection device 2. Calculate the amount of leakage.
[0015]
Here, an operation control method of the adjusting unit 28 by the control unit 36 will be described.
Prior to starting measurement of the fuel injection device 2 connected to the passage portion 20, the control portion 36 controls the adjustment portion 28 to adjust the introduced oil volume. At this time, the introduced oil volume is adjusted so that the height of the liquid level S in the measuring tube 24 exactly matches the reference height H ₀ as shown in FIG.
[0016]
In the liquid leakage measuring device 10, when a liquid leakage occurs in the fuel injection device 2 connected to the passage portion 20, the leaked measurement oil flows into the connection passage 21 of the passage portion 20, and FIG. As indicated by the white arrow, the height of the liquid level S increases in the measuring tube 24. Based on the signal sent from the detection unit 26, the control unit 36 monitors the transition of the liquid level as shown in FIG. As a result of the rise in the liquid level, when the liquid level reaches the upper limit height H _max that is a predetermined distance away from the reference height H ₀ as shown in FIGS. Control to reduce the volume of oil introduced. At this time, the volume of the introduced oil is reduced so that the liquid level is lowered to the reference height H ₀ as shown in FIGS. Incidentally, within a predetermined measuring time T as shown in FIG. 4, the liquid level is lowering the volume reduction and liquid level of the incoming oil volume every time it reaches the upper limit height H _max. Further, the upper limit height H _max is set as small as possible so that the residual oil adhering to the inner wall of the measuring tube 24 is lower than the reference height H ₀ after the liquid level height is lowered.
[0017]
Next, a method for calculating the amount of liquid leakage by the control unit 36 will be described.
The control unit 36 calculates the amount of liquid leakage based on the transition of the liquid level in the measuring tube 24. Specifically, the liquid leakage amount is obtained from the sum of two physical quantities V ₁ and V ₂ that reflect the transition of the liquid level. Here, as shown in FIG. 5, _one physical quantity V ₁ is a liquid volume corresponding to an increase ΔH (see FIG. 4) in the liquid level height at the end of measurement t _e , for example, an increase in the liquid level height. It can be calculated by the product of the amount ΔH and the cross-sectional area of the measuring tube 24. Further, as shown in FIG. 5, the other physical quantity V ₂ is the total volume reduction volume of the introduced oil within the measurement time T. For example, the cross-sectional area of the piston 31 (cylinder 30) and the piston 31 within the measurement time T It can be calculated by the product of the amount of movement.
As described above, in the present embodiment, the detection unit 26 and the control unit 36 together constitute a control unit, and the control unit 36 constitutes an arithmetic unit.
[0018]
Hereinafter, a method for measuring the liquid leakage amount from the fuel injection device 2 using the above-described liquid leakage amount measuring apparatus 10 will be described.
(1) After the fuel injection device 2 is held by the clamp device 12 of the holding portion 11, the clamp device 12 is moved closer to the passage portion 20, and the injection port 6 of the fuel injection device 2 is connected to the connection recess of the passage portion 20. 22 is connected.
(2) The measurement oil is supplied into the fuel injection device 2 through the supply pipe 13.
[0019]
(3) The control unit 36 controls the adjusting unit 28 to adjust the introduced oil volume, so that the liquid level in the measuring tube 24 is precisely matched with the reference height H ₀ .
(4) Start measuring the amount of liquid leakage.
(5) While the liquid level in the measuring tube 24 is monitored by the control unit 36 and the liquid level reaches the upper limit height H _max , the control unit 36 controls the adjustment unit 28 to introduce it. the oil volume was reduced to return the liquid surface level in the reference height H _0.
(6) When the measurement is completed, the amount of liquid leakage from the fuel injection device 2 is calculated. Furthermore, when the liquid level in the measurement tube 24 is higher than the reference height H ₀ , the measurement oil in the connection passage 21 is discharged from a drain port (not shown) for the next measurement. in return the liquid level to the reference height H _0.
[0020]
In the described liquid leakage quantity measuring device 10 described above, since the liquid surface height of the measuring tube 24 at the time of one measurement liquid level reaches the upper limit height H _max is lowered, the inner wall wetted by the liquid level rise The area of is not greatly expanded in the tube axis direction. Therefore, when returning the liquid level to the reference height H ₀ in (6) above, the residual oil adhering to the pipe inner wall above the reference height H ₀ can be lowered in a short time. Therefore, even if the time interval from the end of the previous measurement to the start of the next measurement is short, the liquid level can be sufficiently stabilized by the next measurement.
[0021]
Further, in the liquid leak amount measuring apparatus 10, the liquid leak amount is obtained from the sum of the two physical quantities V ₁ and V ₂ reflecting the transition of the liquid surface height in the measuring tube 24. Therefore, the liquid leak amount is obtained by a relatively simple calculation. The amount can be accurately calculated.
As described above, according to the liquid leakage measuring apparatus 10, it is possible to measure the liquid leakage from the fuel injection device 2 with high accuracy and efficiency.
[0022]
In the above embodiment, when the liquid level in the measuring tube 24 reaches the predetermined upper limit height H _max , the liquid level is lowered to the reference height H ₀ at the start of measurement. However, it may be lowered to a height between the reference height H ₀ and the upper limit height H _max . In the above embodiment, the leakage amount from the fuel injector 2 to be measured portion thereof, the liquid volume V ₁ corresponding to the rise ΔH of liquid level measurement end time t _e, the measurement time T Was obtained by the sum (V ₁ + V ₂ ) of the total volume reduction volume V ₂ of the introduced oil. On the other hand, in order to simplify the calculation, the liquid leakage amount may be obtained based only on the liquid level. Specifically, as shown in FIG. 6, the liquid volume V _11, V ₁₂ corresponding to the increase in the drop just before the liquid level, which corresponds to the increase in the liquid level measurement end time t _e it is possible to calculate the leakage amount by the sum of the liquid volume V _13.
[0023]
Further, in the above embodiment, the measurement tube 24 is arranged to extend in the vertical direction. However, if the liquid level in the tube axis direction can be detected, the measurement tube is inclined to the vertical axis. 24 may be provided.
Furthermore, in the above embodiment, the fuel injection device 2 is handled as an object to be measured. However, any article that can store liquid in a liquid-tight manner can be the object to be measured of the present invention.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a liquid leakage amount measuring apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic diagram for explaining the operation of the liquid leakage amount measuring apparatus shown in FIG.
FIG. 3 is a characteristic diagram for explaining the operation of the liquid leakage amount measuring apparatus shown in FIG. 1;
FIG. 4 is another characteristic diagram for explaining the operation of the liquid leakage amount measuring apparatus shown in FIG. 1;
FIG. 5 is a characteristic diagram for explaining a method for calculating a liquid leakage amount in the liquid leakage amount measuring apparatus shown in FIG. 1;
6 is a characteristic diagram for explaining another method for calculating the liquid leakage amount in the liquid leakage amount measuring apparatus shown in FIG. 1; FIG.
[Explanation of symbols]
2 Fuel injection device (object to be measured)
DESCRIPTION OF SYMBOLS 10 Liquid leak amount measuring apparatus 11 Holding | maintenance part 20 Passage part 21 Connection path 24 Measuring pipe 26 Detection part (control means)
28 adjustment unit 36 control unit (control means, calculation means)

Claims

A liquid leakage amount measuring device for measuring the amount of liquid leakage from a measurement object containing liquid,
A passage portion connected to the measurement target portion so that liquid leaked from the measurement target portion of the object to be measured can flow in;
A measuring tube in which the upper end side is opened to the atmosphere and the lower end side is connected to the passage portion, and the liquid in the passage portion flows into the tube;
An adjustment unit for adjusting the volume of the introduction liquid introduced into the passage part and the measurement tube;
When the liquid level in the measuring tube rises and reaches a predetermined height due to liquid leakage from the object to be measured, the adjustment unit is controlled to reduce the volume of the introduced liquid and reduce the liquid level height. Control means for lowering;
A calculation means for calculating the liquid leakage amount based on the transition of the liquid level height;
A liquid leakage amount measuring device comprising:

The liquid leakage amount is obtained by a sum of a liquid volume corresponding to an increase in the liquid level at the end of measurement and a total volume reduction volume of the introduced liquid within a measurement time. The liquid leakage amount measuring apparatus according to 1.

A liquid leakage amount measuring method for measuring a liquid leakage amount from a measurement object containing a liquid,
A passage portion connected to the measurement target portion so that liquid leaked from the measurement target portion of the object to be measured can flow in, and an upper end side is opened to the atmosphere and a lower end side is connected to the passage portion, so that the liquid in the passage portion is Using a device comprising a measurement tube flowing into the tube, and an adjustment unit for adjusting the volume of the introduced liquid introduced into the passage portion and the measurement tube,
When the liquid level in the measuring tube rises and reaches a predetermined height due to liquid leakage from the object to be measured, the volume of the introduced liquid is reduced by the adjusting unit to lower the liquid level. ,
A liquid leak amount measuring method, wherein the liquid leak amount is calculated based on a transition of the liquid level height.

The liquid leakage amount is obtained by a sum of a liquid volume corresponding to an increase in the liquid level at the end of measurement and a total volume reduction volume of the introduced liquid within a measurement time. 3. A method for measuring a leakage amount according to 3.