JPH0242189B2 - - Google Patents
Info
- Publication number
- JPH0242189B2 JPH0242189B2 JP57198872A JP19887282A JPH0242189B2 JP H0242189 B2 JPH0242189 B2 JP H0242189B2 JP 57198872 A JP57198872 A JP 57198872A JP 19887282 A JP19887282 A JP 19887282A JP H0242189 B2 JPH0242189 B2 JP H0242189B2
- Authority
- JP
- Japan
- Prior art keywords
- cylinder
- rings
- gas
- piston
- liner
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000002485 combustion reaction Methods 0.000 claims description 6
- 238000005259 measurement Methods 0.000 description 5
- 238000007789 sealing Methods 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000003754 machining Methods 0.000 description 2
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/0061—Force sensors associated with industrial machines or actuators
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/02—Details or accessories of testing apparatus
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
- Testing Of Engines (AREA)
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は内燃機関のピストン摩擦力測定装置の
改良に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a piston friction force measuring device for an internal combustion engine.
［従来の技術］
ピストン摩擦力測定装置は特開昭56−22921号
公報によつて公知である。その公知装置はシリン
ダをシリンダブロツクに対して相対変位可能に支
持し、その相対変位を検出する検出装置をシリン
ダとシリンダブロツク間に取付け、その変位を検
出してピストン摩擦力を測定するものであるが、
ピストンが上死点にあるときのガス圧によるシリ
ンダの変形を防止するため、シリンダ上部を密封
するためのＯリングを保持するＯリングホルダを
シリンダブロツクに固着してシリンダヘツドから
分離し、そのＯリングを収容する溝をシリンダの
内壁とＯリングホルダの双方にまたがつて設け、
その溝にＯリングを収容し、Ｏリングホルダとシ
リンダヘツドの間にシリンダ内に連通する空間を
設け、その空間の外周部に耐熱性のシールリング
を嵌着し、シリンダ内のガス圧力が作用するシリ
ンダ及びＯリングホルダの上下方向の受圧面積を
等しくし、前記シリンダ及びシリンダブロツクに
作用するガス圧力が上下方向に均等となるように
していた。[Prior Art] A piston friction force measuring device is known from Japanese Patent Laid-Open No. 56-22921. In this known device, a cylinder is supported so as to be movable relative to a cylinder block, a detection device for detecting the relative displacement is installed between the cylinder and the cylinder block, and the piston friction force is measured by detecting the displacement. but,
To prevent the cylinder from deforming due to gas pressure when the piston is at top dead center, the O-ring holder that holds the O-ring for sealing the top of the cylinder is fixed to the cylinder block and separated from the cylinder head. A groove for accommodating the ring is provided across both the inner wall of the cylinder and the O-ring holder,
The O-ring is accommodated in the groove, a space is provided between the O-ring holder and the cylinder head that communicates with the inside of the cylinder, and a heat-resistant seal ring is fitted around the outer periphery of the space, so that the gas pressure inside the cylinder acts on the O-ring. The pressure receiving areas in the vertical direction of the cylinder and the O-ring holder are made equal, so that the gas pressure acting on the cylinder and the cylinder block is made equal in the vertical direction.
［発明が解決しようとする課題］
公知装置はシリンダ上部を密封するためのＯリ
ングを保持するＯリングホルダをシリンダブロツ
クに固着してシリンダヘツドから分離し、Ｏリン
グホルダとシリンダヘツドの間にシリンダ内に連
通する空間を設け、その空間に耐熱性のシールリ
ングを嵌着する構成のため、シリンダヘツド、シ
リンダブロツク、ピストンを加工しなければなら
ず、又、その加工したところへ取付けるＯリング
ホルダとシールリングを新たに製作しなければな
らなかつたが、加工時に要する費用が多大な上
に、取付時に手間がかかり測定が容易ではないと
いう問題があつた。[Problems to be Solved by the Invention] A known device fixes an O-ring holder holding an O-ring for sealing the upper part of the cylinder to a cylinder block and separates it from the cylinder head, and places the cylinder between the O-ring holder and the cylinder head. Because the cylinder head, cylinder block, and piston must be machined to create a space that communicates with the inside and a heat-resistant seal ring is fitted into that space, an O-ring holder must be attached to the machined part. A new seal ring had to be manufactured, but there were problems in that it was expensive to process, and it took time and effort to install, making it difficult to measure.
本発明はこの問題点を解決するためになされた
ものであり、その目的とするところは、シリンダ
ブロツク等を加工しなくてもシリンダに作用する
ガス圧の影響を受けずにピストン摩擦力の測定が
可能な装置を提供することにある。 The present invention was made to solve this problem, and its purpose is to measure the piston friction force without machining the cylinder block or the like and without being affected by the gas pressure acting on the cylinder. The goal is to provide a device that allows
［課題を解決するための手段］
前記目的を達成するため、本発明が採用する手
段は、第１図に示すように、内燃機関のシリンダ
２を三段のＯリング１１，１３，１４を介してラ
イナ３又はブロツク９に変位可能に内嵌し、シリ
ンダ２をライナ３又はブロツク９に設けた荷重ピ
ツクアツプ５のみで支持し、シリンダ内のガス圧
を前記シリンダに設けたガス貫通孔７を通してそ
の内部から中及び下段のＯリング１３，１４で囲
まれた外周部に導くことによりシリンダに背圧を
かけ、シリンダの上端面に作用する圧力と背圧が
バランスするように各Ｏリングを設定し、荷重ピ
ツクアツプを通じてシリンダに作用する軸方向の
力を測定するようにしたことにある。[Means for Solving the Problems] In order to achieve the above object, the means adopted by the present invention is to connect the cylinder 2 of the internal combustion engine through three stages of O-rings 11, 13, and 14, as shown in FIG. The cylinder 2 is displaceably fitted into the liner 3 or block 9, and the cylinder 2 is supported only by the load pickup 5 provided in the liner 3 or block 9, and the gas pressure inside the cylinder is transferred through the gas through hole 7 provided in the cylinder. Back pressure is applied to the cylinder by guiding it from the inside to the outer periphery surrounded by the middle and lower O-rings 13 and 14, and each O-ring is set so that the pressure acting on the upper end surface of the cylinder and the back pressure are balanced. , the axial force acting on the cylinder is measured through a load pickup.
［作用］
シリンダ内のガス圧力、特にピストン１が上死
点にあるときの圧力は非常に大きいが、ガス圧力
はシリンダ２に設けたガス貫通孔７からシリンダ
２の外周に導かれて背圧となり、その背圧とシリ
ンダ上端部に作用するガス圧力とがバランスする
から、シリンダに作用するガス圧の影響を受けず
にピストン摩擦力を測定することができる。この
バランスをとるために施される特別な加工はシリ
ンダのガス貫通孔のみであるから、従来のシリン
ダヘツド及びブロツクを加工し、その加工した空
間にＯリングホルダやシールリングを製作して取
付けていたものに比較すると、測定に要する費用
は大幅に節減される。[Function] The gas pressure inside the cylinder, especially the pressure when the piston 1 is at the top dead center, is very high, but the gas pressure is led from the gas through hole 7 provided in the cylinder 2 to the outer periphery of the cylinder 2, creating back pressure. Since the back pressure and the gas pressure acting on the upper end of the cylinder are balanced, the piston friction force can be measured without being influenced by the gas pressure acting on the cylinder. The only special processing required to achieve this balance is the gas through hole in the cylinder, so the conventional cylinder head and block are processed, and an O-ring holder and seal ring are manufactured and installed in the processed space. Compared to conventional methods, the cost of measurement is significantly reduced.
［実施例］
本発明の装置を図面に示す実施例に基づいて説
明する。第１図及び第２図に示すように、単気筒
テスト用エンジンのシリンダ２をライナ３に上か
ら挿入し、シリンダ２とライナ３の間にベアリン
グ等の揺れ止め４を嵌着する。シリンダ２の下端
部周面に接圧子２１を固定し、ライナ下端に固定
した支持部材３１と前記接圧子の間に荷重ピツク
アツプをセツトしているが、前記支持部材はブロ
ツクに固定してもよい。シリンダ２の内部にピス
トン１を入れ、シリンダヘツド８で上を覆う。ピ
ストン１にピストンリング６をはめ、その第一圧
力リングの上死点より上の位置においてシリンダ
２にガス貫通孔７をあける。[Example] The apparatus of the present invention will be described based on an example shown in the drawings. As shown in FIGS. 1 and 2, the cylinder 2 of a single-cylinder test engine is inserted into the liner 3 from above, and a vibration stopper 4 such as a bearing is fitted between the cylinder 2 and the liner 3. The pressure element 21 is fixed to the circumferential surface of the lower end of the cylinder 2, and a load pickup is set between the support member 31 fixed to the lower end of the liner and the pressure element, but the support member may be fixed to a block. . A piston 1 is placed inside a cylinder 2, and the top is covered with a cylinder head 8. A piston ring 6 is fitted onto the piston 1, and a gas through hole 7 is formed in the cylinder 2 at a position above the top dead center of the first pressure ring.
シリンダ２の上端部を三段に形成し、その段部
とライナ３の間に三重のガスシール用Ｏリング１
１，１３，１４を設け、中段のＯリング１３の有
効径を最大にする。ガス貫通孔７からシリンダ２
の外周に導かれたガスの背圧はシリンダ２を軸方
向に持上げ、シリンダ２の上端部に作用する圧力
はシリンダ２を軸方向に押し下げる作用をする。
この上下の圧力をバランスさせるため、上中下各
段のＯリング１１，１３，１４の有効径D1、
D3、D4とシリンダの内径D2を次式が成立するよ
うに設定する。 The upper end of the cylinder 2 is formed into three stages, and a triple O-ring 1 for gas sealing is formed between the stages and the liner 3.
1, 13, and 14 are provided to maximize the effective diameter of the middle O-ring 13. From gas through hole 7 to cylinder 2
The back pressure of the gas guided to the outer periphery of the cylinder 2 lifts the cylinder 2 in the axial direction, and the pressure acting on the upper end of the cylinder 2 acts to push the cylinder 2 down in the axial direction.
In order to balance this upper and lower pressure, the effective diameter D1 of the O-rings 11, 13, and 14 in the upper, middle, and lower stages,
Set D3, D4 and the inner diameter D2 of the cylinder so that the following formula holds.
π／４（D12−D22）＝π／４（D32−D42）
シリンダ２の上端に作用する加圧力はシリンダ
２とピストン１の間の摩擦力よりもはるかに大き
いので、加圧力を背圧によりバランスさせない
と、摩擦力を測定することはできない。しかし、
本発明の装置によると、ガス圧力はシリンダ軸方
向の力には関与しないので、シリンダの軸方向に
作用する力はシリンダ２とピストン１すなわちピ
ストンリング６の間の摩擦力のみとなる。したが
つて、ピツクアツプ５を通じてシリンダ２の軸方
向に作用する力を測定すれば、それがそのままピ
ストンの摩擦力になる。π/4 (D1 2 - D2 2 ) = π/4 (D3 2 - D4 2 ) The pressurizing force acting on the upper end of cylinder 2 is much larger than the frictional force between cylinder 2 and piston 1, so the pressurizing force Frictional force cannot be measured unless it is balanced by back pressure. but,
According to the device of the present invention, the gas pressure does not contribute to the force in the axial direction of the cylinder, so that the only force acting in the axial direction of the cylinder is the frictional force between the cylinder 2 and the piston 1, that is, the piston ring 6. Therefore, if the force acting in the axial direction of the cylinder 2 is measured through the pick-up 5, it becomes the frictional force of the piston.
また、前記ガス貫通孔７を設けることにより、
シリンダ外周の圧力とシリンダ内圧力のバランス
がとれ、特にシリンダ上死点近傍でのシリンダの
変形を防止することができ、正確なピストン摩擦
力の測定が可能となる。 Furthermore, by providing the gas through hole 7,
The pressure on the outside of the cylinder and the pressure inside the cylinder are balanced, and deformation of the cylinder can be prevented, especially near the top dead center of the cylinder, making it possible to accurately measure piston frictional force.
図示したエンジンはシリンダボア137mm、スト
ローク135mmの直接噴射式デイーゼルエンジンで
あり、圧力リング３本と油かきリング１本を備え
ている。このエンジンを全負荷、半負荷、無負荷
において一定の回転数（1000RPM）で運転し、
荷重ピツクアツプを通じてシリンダとピストンリ
ングの間の摩擦力のみに基づく軸方向の力を測定
し、第３図にその測定結果を図示した。 The engine shown is a direct injection diesel engine with a cylinder bore of 137 mm and a stroke of 135 mm, and is equipped with three pressure rings and one oil paddle ring. This engine is operated at a constant rotation speed (1000 RPM) at full load, half load, and no load.
The axial force based only on the frictional force between the cylinder and the piston ring was measured through a load pickup, and the measurement results are illustrated in FIG.
第３図から圧縮行程の後半と燃焼行程の前半に
おいてピストンの摩擦力は負荷の影響を受け、負
荷が増すに従い摩擦力も増大することがわかつ
た。又、高いガス圧力が作用する時間は１サイク
ルの中の1/4程度で短いこと、さらに、吸排気行
程では逆に摩擦力が減少するため、摩擦損失に対
する影響は比較的小さいことも判明した。 From FIG. 3, it was found that the frictional force of the piston is affected by the load in the latter half of the compression stroke and the first half of the combustion stroke, and as the load increases, the frictional force also increases. It was also found that the time during which high gas pressure is applied is short, about 1/4 of a cycle, and that the effect on friction loss is relatively small because the frictional force decreases during the intake and exhaust strokes. .
［発明の効果］
上記の通り、本発明の装置はガス圧をシリンダ
の内部から外周に導きシリンダに背圧をかけ、そ
の背圧とシリンダに作用する圧力とをバランスさ
せることによりピストン摩擦力の測定がガス圧の
影響を受けないようにしたものであるから、ガス
圧をシリンダヘツドに設けた空間に導き、シリン
ダブロツクに作用する圧力とシリンダに作用する
内圧とをバランスさせていガス圧の影響を受けな
いようにしていた従来の測定装置とは異なり、本
発明の装置はシリンダヘツド等を加工して空間を
設ける必要も、その空間にＯリングホルダとシー
ルリングを取付ける必要もないから、従来のもの
に比較すると測定に要する費用が大幅に節減さ
れ、測定が容易に実施できるという格別の効果が
得られる。[Effects of the Invention] As described above, the device of the present invention guides gas pressure from the inside of the cylinder to the outer periphery, applies back pressure to the cylinder, and balances the back pressure with the pressure acting on the cylinder, thereby reducing piston frictional force. Since the measurement is not affected by gas pressure, the gas pressure is introduced into the space provided in the cylinder head, and the pressure acting on the cylinder block and the internal pressure acting on the cylinder are balanced. Unlike conventional measuring devices, which are designed to avoid damage, the device of the present invention does not require creating a space by machining the cylinder head or the like, nor does it require installing an O-ring holder and seal ring in that space. Compared to conventional methods, the cost required for measurement is greatly reduced and measurements can be easily carried out.
第１図は本発明の装置を設けたデイーゼルエン
ジンの要部を示す断面図、第２図は第１図の部分
拡大図、第３図は本発明の装置により測定したピ
ストン摩擦力をクランク角度に対して示す図であ
る。
１：ピストン、２：シリンダ、３：ライナ、
４：揺れ止め、５：荷重ピツクアツプ、６：ピス
トンリング、７：ガス貫通孔、８：シリンダヘツ
ド、９：ブロツク、１１，１３，１４：Ｏリン
グ、２１：接圧子、３１：支持部材。
Fig. 1 is a sectional view showing the main parts of a diesel engine equipped with the device of the present invention, Fig. 2 is a partially enlarged view of Fig. 1, and Fig. 3 shows the piston friction force measured by the device of the present invention at the crank angle. FIG. 1: Piston, 2: Cylinder, 3: Liner,
4: anti-sway, 5: load pickup, 6: piston ring, 7: gas through hole, 8: cylinder head, 9: block, 11, 13, 14: O-ring, 21: contact element, 31: support member.
Claims (1)
た荷重ピツクアツプ５のみで支持し、前記荷重ピ
ツクアツプを通じて前記シリンダに作用する軸方
向の力を測定する装置において、前記シリンダは
上中下三段のＯリング１１，１３，１４を介して
前記ライナ又は前記ブロツクに変位可能に内嵌さ
れ、前記中及び下段のＯリング１３，１４に囲ま
れた外周部と前記シリンダ上端面のガスを通気さ
せるガス貫通孔７を設け、前記三段のＯリングを
前記シリンダの上端面に作用する圧力と前記中及
び下段のＯリングに囲まれた外周部に生ずる背圧
とがバランスするように設定したことを特徴とし
てなる内燃機関のピストン摩擦力測定装置。 ２ シリンダ２とライナ３の間の揺れ止め４を設
けて軸方向にのみ力が作用するようにしたことを
特徴としてなる特許請求の範囲第１項に記載の内
燃機関のピストン摩擦力測定装置。 ３ 上中下三段のガスシール用Ｏリングの有効径
D1、D3、D4とシリンダの内径D2を、 （D12−D22）＝（D32−D42）の関係が成立する
ように設定したことを特徴としてなる特許請求の
範囲第１項又は第２項に記載の内燃機関のピスト
ン摩擦力測定装置。[Scope of Claims] 1. In an apparatus in which a cylinder 2 is supported only by a load pickup 5 provided on a liner 3 or a block 9, and an axial force acting on the cylinder through the load pickup is measured, the cylinder is The gas is displaceably fitted into the liner or the block via the lower three O-rings 11, 13, 14, and the outer circumference surrounded by the middle and lower O-rings 13, 14 and the upper end surface of the cylinder. A gas through hole 7 is provided to ventilate the three O-rings so that the pressure acting on the upper end surface of the cylinder and the back pressure generated at the outer periphery surrounded by the middle and lower O-rings are balanced. A piston friction force measuring device for an internal combustion engine characterized by the following settings. 2. A piston friction force measuring device for an internal combustion engine according to claim 1, characterized in that a rocking stop 4 is provided between the cylinder 2 and the liner 3 so that force acts only in the axial direction. 3 Effective diameter of O-rings for gas seals in upper, middle, and lower stages
Claim 1 or Claim 1 characterized in that D1, D3, D4 and the inner diameter D2 of the cylinder are set so that the relationship (D1 2 −D2 2 )=(D3 2 −D4 2 ) holds true. The piston friction force measuring device for an internal combustion engine according to item 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57198872A JPS5988638A (en) | 1982-11-15 | 1982-11-15 | Method for measuring piston friction force of internal combustion engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57198872A JPS5988638A (en) | 1982-11-15 | 1982-11-15 | Method for measuring piston friction force of internal combustion engine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5988638A JPS5988638A (en) | 1984-05-22 |
| JPH0242189B2 true JPH0242189B2 (en) | 1990-09-20 |
Family
ID=16398320
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57198872A Granted JPS5988638A (en) | 1982-11-15 | 1982-11-15 | Method for measuring piston friction force of internal combustion engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5988638A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013543972A (en) * | 2010-11-09 | 2013-12-09 | アー・ファウ・エル・リスト・ゲー・エム・ベー・ハー | Friction measuring device |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100376687B1 (en) * | 2000-07-13 | 2003-03-15 | 현대자동차주식회사 | Pressure compensation type floating liner mounting structure |
| KR100394635B1 (en) * | 2000-12-28 | 2003-08-14 | 현대자동차주식회사 | A mounting structure of floating liner for measuring friction of piston |
| DE102010015883B4 (en) | 2010-03-09 | 2012-12-13 | Technische Universität München | Gas power compensation |
| CN103940599B (en) * | 2014-04-14 | 2016-10-19 | 浙江大学 | Pneumatic muscles/cylinder integrated test system |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5622921A (en) * | 1979-08-01 | 1981-03-04 | Hino Motors Ltd | Measuring instrument for frictional force of piston |
-
1982
- 1982-11-15 JP JP57198872A patent/JPS5988638A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5622921A (en) * | 1979-08-01 | 1981-03-04 | Hino Motors Ltd | Measuring instrument for frictional force of piston |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013543972A (en) * | 2010-11-09 | 2013-12-09 | アー・ファウ・エル・リスト・ゲー・エム・ベー・ハー | Friction measuring device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5988638A (en) | 1984-05-22 |
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