JP4849235B2 - Sealing device - Google Patents

Sealing device Download PDF

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Publication number: JP4849235B2
Authority: JP; Japan
Prior art keywords: shaft hole; hole housing; sealing device; peripheral surface; inner peripheral
Prior art date: 2006-09-19
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.): Active

Application number

JP2006252632A

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Japanese (ja)

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JP2008075679A (en

Inventor

岳洋中川

昌幸谷田

Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)

Nok Corp

Original Assignee

Nok Corp

Priority date (The priority date 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 date listed.)

2006-09-19

Filing date

2006-09-19

Publication date

2012-01-11

2006-09-19 Application filed by Nok Corp filed Critical Nok Corp

2006-09-19 Priority to JP2006252632A priority Critical patent/JP4849235B2/en

2008-04-03 Publication of JP2008075679A publication Critical patent/JP2008075679A/en

2012-01-11 Application granted granted Critical

2012-01-11 Publication of JP4849235B2 publication Critical patent/JP4849235B2/en

Status Active legal-status Critical Current

2026-09-19 Anticipated expiration legal-status Critical

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Sealing With Elastic Sealing Lips (AREA)

Description

本発明は、自動車や一般機械、産業機械等において、軸孔ハウジングとこれに回転又は軸方向往復動可能に挿通された軸との間を密封する密封装置に関するものである。 The present invention relates to a sealing device that seals between a shaft hole housing and a shaft inserted into the shaft hole housing so as to be rotatable or reciprocally movable in an axial direction in automobiles, general machines, industrial machines, and the like.

機器の軸孔ハウジングとこれに挿通された回転軸との間でオイル等を密封するために使用される密封装置としては、例えば特許文献１のようなオイルシールが良く知られている。
特開２００２−２０６６４４号公報 As a sealing device used for sealing oil or the like between a shaft hole housing of a device and a rotating shaft inserted therethrough, an oil seal as disclosed in Patent Document 1, for example, is well known.
JP 2002-206644 A

図５は、特許文献１と同種の、従来の密封装置（オイルシール）１００を、軸心Ｏを通る平面で切断して示す半断面図である。すなわち、この密封装置１００は、金属板の打ち抜きプレス成形等により製作された補強環１０５にゴム状弾性材料で一体成形されたもので、略円筒状のガスケット部１０１と、その機外空間Ｂ側となる端部から内周側へ延びるリップホルダ部１０２と、このリップホルダ部１０２の内周端からガスケット部１０１及びリップホルダ部１０２と共に断面略コ字形をなすように、機内空間Ａ側へ向けて延びるシールリップ１０３と、前記リップホルダ部１０２の内周端からシールリップ１０３と反対側（機外空間Ｂ側）へ向けて延びるダストリップ１０４と、ガスケット部１０１及びリップホルダ部１０２に跨って埋設された補強用の補強環１０５と、シールリップ１０３に嵌着されたエキステンションスプリング１０６とを有する。
FIG. 5 is a half cross-sectional view showing a conventional sealing device (oil seal) 100 of the same type as that of Patent Document 1, cut along a plane passing through the axis O. That is, the sealing device 100 is integrally formed of a rubber-like elastic material on a reinforcing ring 105 manufactured by stamping press molding of a metal plate or the like, and has a substantially cylindrical gasket portion 101 and its outside space B side. The lip holder portion 102 extending from the end to the inner peripheral side, and toward the in-machine space A side so as to form a substantially U-shaped cross section with the gasket portion 101 and the lip holder portion 102 from the inner peripheral end of the lip holder portion 102 The seal lip 103 that extends, the dust lip 104 that extends from the inner peripheral end of the lip holder portion 102 toward the side opposite to the seal lip 103 (external space B side), the gasket portion 101 and the lip holder portion 102 A reinforcing ring 105 for reinforcement embedded therein and an extension spring 106 fitted to the seal lip 103 are provided.

ガスケット部１０１は、軸孔ハウジング１１０の内周面に圧入され、補強環１０５との間で適当に圧縮されることによって、所要の密封力を発揮すると共に、軸孔ハウジング１１０との軸方向固定力が与えられる。また、シールリップ１０３は、その内周のシールエッジ１０３ａが、軸孔ハウジング１１０に挿通された回転軸１２０の外周面に、適当な緊迫力をもって摺動可能に密接され、ダストリップ１０４は、その内周縁が、前記回転軸１２０の外周面に、微小隙間をもって近接されるか、僅かな締め代をもって摺動可能に密接される。 The gasket portion 101 is press-fitted into the inner peripheral surface of the shaft hole housing 110 and is appropriately compressed between the reinforcing ring 105 and exhibits a required sealing force and is fixed to the shaft hole housing 110 in the axial direction. Power is given. Further, the seal lip 103 has its inner peripheral seal edge 103a slidably in close contact with the outer peripheral surface of the rotary shaft 120 inserted through the shaft hole housing 110 with an appropriate pressing force. The inner peripheral edge is brought close to the outer peripheral surface of the rotating shaft 120 with a small gap or is slidably in contact with a slight tightening margin.

ところが、この種の密封装置１００は、軸孔ハウジング１１０への固定力を、ゴム状弾性材料からなるガスケット部１０１の圧縮反力に由来する圧接力にのみ依存しているため、特に、例えば軸孔ハウジング１１０の内径と回転軸１２０の外径との径寸法差Δφが大きく、すなわち機内空間Ａの内圧に対する受圧面積が大きい場合は、機内空間Ａの僅かな圧力上昇でも機外空間Ｂ側への軸方向荷重が大きくなるので、軸孔ハウジング１１０から密封装置１００が離脱してしまうおそれがある。 However, since this type of sealing device 100 relies only on the pressure contact force derived from the compression reaction force of the gasket portion 101 made of a rubber-like elastic material, the fixing force to the shaft hole housing 110 depends particularly on, for example, the shaft. When the diameter difference Δφ between the inner diameter of the hole housing 110 and the outer diameter of the rotary shaft 120 is large, that is, when the pressure receiving area with respect to the internal pressure of the internal space A is large, even a slight pressure increase in the internal space A moves toward the external space B side. Since the axial load increases, the sealing device 100 may be detached from the shaft hole housing 110.

また、例えば軸孔ハウジング１１０がアルミ材のような熱膨張係数の大きい材料からなるものである場合は、温度上昇時に、密封装置１００の内部の補強環１０５と軸孔ハウジング１１０との熱膨張量の差によって、両者１０５，１１０間でのガスケット部１０１の径方向圧縮量が減少又は喪失するので、この場合も、軸孔ハウジング１１０から密封装置１００が離脱してしまうおそれがある。 For example, when the shaft hole housing 110 is made of a material having a large thermal expansion coefficient such as an aluminum material, the amount of thermal expansion between the reinforcing ring 105 inside the sealing device 100 and the shaft hole housing 110 when the temperature rises. Due to this difference, the amount of radial compression of the gasket portion 101 between the two 105 and 110 is reduced or lost, so that the sealing device 100 may be detached from the shaft hole housing 110 in this case as well.

そして、このような温度上昇時の密封装置１００の離脱を防止するには、補強環１０５と軸孔ハウジング１１０との熱膨張差によるガスケット部１０１の径方向圧縮量の減少を見込んで、予めガスケット部１０１の径方向圧縮代を大きく設定しておくことが有効であるが、この場合は、当該密封装置１００を軸孔ハウジング１１０の内周に組み付ける際の圧入抵抗が大きくなって、組み付け作業性が著しく悪化するばかりでなく、軸孔ハウジング１１０やガスケット部１０１が損傷を受けるおそれがある。 In order to prevent such a separation of the sealing device 100 when the temperature rises, the gasket portion 101 is expected to be reduced in the radial compression amount due to a difference in thermal expansion between the reinforcing ring 105 and the shaft hole housing 110, and the gasket is previously determined. It is effective to set the radial compression allowance of the portion 101 large, but in this case, the press-fit resistance when the sealing device 100 is assembled to the inner periphery of the shaft hole housing 110 is increased, and the assembly workability is increased. In addition to the remarkable deterioration, the shaft hole housing 110 and the gasket portion 101 may be damaged.

本発明は、以上のような点に鑑みてなされたものであって、その技術的課題とするところは、機内空間の圧力による軸方向荷重の増大や、軸孔ハウジングの熱膨張によるガスケット部の径方向圧縮量の減少によって、軸孔ハウジングから密封装置が離脱するのを防止することにある。 The present invention has been made in view of the above points, and the technical problem is that an increase in the axial load due to the pressure in the in-machine space and the gasket portion due to the thermal expansion of the shaft hole housing. It is to prevent the sealing device from being detached from the shaft hole housing by reducing the amount of radial compression.

上述した技術的課題を有効に解決するための手段として、請求項１の発明に係る密封装置は、軸孔ハウジングの内周面に密嵌されるゴム状弾性材料からなるガスケット部が形成された外周基部と、その内周側から機内空間側へ延びて、前記軸孔ハウジングに挿通された軸の外周面に摺動可能に密接されるゴム状弾性材料からなるシールリップと、前記ガスケット部の間に形成された溝部に嵌め込んで取り付けられ、自由状態では前記軸孔ハウジングの想定し得る熱膨張時の内周面よりも大径で略線形のばね特性を有するラジアルスプリングとを備え、前記ラジアルスプリングが、円周方向一箇所で切断された環状体からなるものである。
As a means for effectively solving the above technical problem, the sealing device according to the invention of claim 1 is formed with a gasket portion made of a rubber-like elastic material that is tightly fitted to the inner peripheral surface of the shaft hole housing. An outer peripheral base, a seal lip made of a rubber-like elastic material that extends from the inner peripheral side to the inner space side and is slidably in contact with the outer peripheral surface of the shaft inserted into the shaft hole housing; and the gasket portion attached is fitted into a groove formed between, in the free state and a radial spring having spring characteristics of substantially linear with a diameter larger than the inner peripheral surface at the time conceivable thermal expansion of the shaft hole housing, the A radial spring consists of an annular body cut at one place in the circumferential direction .

上記構成において、ラジアルスプリングは、軸孔ハウジングの熱膨張によって、その内周面に密接されたガスケット部の径方向圧縮量が減少しても、ラジアルスプリングが拡径して軸孔ハウジングの内周面に追随して圧接し、しかも略線形のばね特性を有するため、軸孔ハウジングの内周面との圧接力の減少は、ゴム状弾性材料からなるガスケット部に比較して小さい。このため、軸孔ハウジングに対する密封装置の軸方向固定力が補償される。また、このラジアルスプリングは、縮径変形させても径方向荷重が非線形的に急激に増大することがないので、軸孔ハウジングの内周に組み付ける際の圧入抵抗の増大が抑えられる。 In the above configuration, the radial spring expands to the inner periphery of the shaft hole housing even if the radial compression amount of the gasket portion in close contact with the inner peripheral surface decreases due to the thermal expansion of the shaft hole housing. Since it has a substantially linear spring characteristic following the surface and has a substantially linear spring characteristic, the decrease in the pressure contact force with the inner peripheral surface of the shaft hole housing is small compared to a gasket portion made of a rubber-like elastic material. For this reason, the axial fixing force of the sealing device with respect to the shaft hole housing is compensated. In addition, even if the radial spring is deformed to a reduced diameter, the radial load does not increase non-linearly and abruptly, so that an increase in press-fit resistance when assembled to the inner periphery of the shaft hole housing can be suppressed.

請求項２の発明に係る密封装置は、請求項１に記載の構成において、ラジアルスプリングが、軸孔ハウジングの内周面に形成された溝又は凹部に係止されるものである。
A sealing device according to a second aspect of the present invention is the sealing device according to the first aspect, wherein the radial spring is engaged with a groove or a recess formed in the inner peripheral surface of the shaft hole housing.

請求項１の発明に係る密封装置�