JPH04183611A - Pneumatic tire excellent in traveling performance on frozen wet ground surface - Google Patents
Pneumatic tire excellent in traveling performance on frozen wet ground surfaceInfo
- Publication number
- JPH04183611A JPH04183611A JP2307297A JP30729790A JPH04183611A JP H04183611 A JPH04183611 A JP H04183611A JP 2307297 A JP2307297 A JP 2307297A JP 30729790 A JP30729790 A JP 30729790A JP H04183611 A JPH04183611 A JP H04183611A
- Authority
- JP
- Japan
- Prior art keywords
- groove
- narrow
- land
- grooves
- tread
- 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.)
- Granted
Links
- 238000005452 bending Methods 0.000 claims abstract description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 8
- 238000007599 discharging Methods 0.000 abstract 1
- 238000012360 testing method Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000009826 distribution Methods 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 239000000155 melt Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000010008 shearing Methods 0.000 description 3
- 239000002344 surface layer Substances 0.000 description 3
- 230000006866 deterioration Effects 0.000 description 2
- 239000002023 wood Substances 0.000 description 2
- 210000001015 abdomen Anatomy 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000012792 core layer Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000007790 scraping Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
- B60C11/03—Tread patterns
- B60C11/12—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes
- B60C11/1204—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes with special shape of the sipe
- B60C2011/1213—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes with special shape of the sipe sinusoidal or zigzag at the tread surface
Landscapes
- Tires In General (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
スタッドレスタイヤを典型として、積雪或いはその凍結
を生じた地表での車両走行に供用されるタイヤは、地表
上の積雪層に対する強いグリップ性能に加えて、核層の
圧潰・融解などによる氷結面や凍結路面に対しても有効
なトラクション及び制動能力をあられす、踏面パターン
を有することがのぞまれる。[Detailed Description of the Invention] (Industrial Application Field) Tires, typically studless tires, which are used for vehicles running on snowy or frozen ground, have a strong grip on the snow layer on the ground. Therefore, it is desired that the tire has a tread pattern that provides effective traction and braking ability even on frozen surfaces and frozen road surfaces caused by crushing and melting of the core layer.
この発明は、乗用車などの一般的な使途ではもちろん、
トラックやバスなど、とくに車体重量が重い車両に装着
される場合も含めて、有効な雪上対策に応じることがで
きてしかも、氷結面及び凍結路面上でのトラクション及
び制動に関して必要な能力を発揮することができる踏面
パターンについての開発研究の成果を提案するものであ
る。This invention can be used not only in general applications such as passenger cars, but also in
Even when installed on particularly heavy vehicles such as trucks and buses, it can be used as an effective countermeasure against snow, and also exhibits the necessary traction and braking capabilities on icy surfaces and frozen roads. This paper proposes the results of development research on tread patterns that can be used.
（従来の技術）
氷結面及び凍結路面上におけるタイヤの走行性能を改善
するための従来の対策は、−Ｍに踏面パターンを構成す
る陵部にサイプとかスリットとか呼ばれる狭幅の切込み
溝を配設し、これによって踏面上に形成されるエツジ作
用の増強を図ることが通例であるところ、これに必要と
される程に多数のサイプを用いると、それによるトレッ
ド剛性の低下が不所望に伴われトラクションに悪影響を
生じるばかりでなく、陵部の曲げ変形により接地面積が
滅じそこでの局部的な圧力上昇に起因する融水が氷結面
、凍結路面での制動性能を却って劣化させる。(Prior art) A conventional measure to improve the running performance of tires on icy surfaces and frozen roads is to arrange narrow grooves called sipes or slits in the ridges that make up the tread pattern on -M. However, although it is customary to enhance the edge action formed on the tread surface, using a large number of sipes as required for this purpose may undesirably reduce tread stiffness. Not only does this have a negative effect on traction, but the bending deformation of the ridges destroys the ground contact area, and the melt water caused by the local pressure increase there actually deteriorates braking performance on icy surfaces and frozen roads.
ちなみに特開昭５６−２１９０５号公報には、タイヤト
レッドの外面法線に対して傾斜した多数の相互近接スリ
ットによりタイヤトレッドの突起要素を分割して構成に
なる冬期走行用タイヤが開示されているが、かかるタイ
ヤでも工・ノジ増しによるトレンド剛性の劣化は免れえ
ず、走行性能のより一層の改善を図るまでには至ってい
ない。Incidentally, Japanese Patent Application Laid-Open No. 56-21905 discloses a tire for winter running that is constructed by dividing the protruding elements of the tire tread by a number of mutually adjacent slits that are inclined with respect to the normal to the outer surface of the tire tread. However, even with such tires, deterioration in trend stiffness due to increased machining and gluing cannot be avoided, and it has not been possible to further improve driving performance.
また特開平２−２１２２０４号公報によると、互いに間
隔をおくサイプ配列の下でサイプの前段にヒールアンド
トウ摩耗が発生するのを、サイプ間隔につき、特定の粗
密配列とする解決策について開示されているが狭い配列
間隔のサイプ間にて広い配列間隔のサイプ間に比しより
低い剛性の活用を目指すのみで後者のサイ１間における
剛性の利用に触れるところはなく、またこれに関連する
ような着想に言及するところもない。Furthermore, Japanese Patent Application Laid-Open No. 2-212204 discloses a solution to prevent heel-and-toe wear from occurring in the front stage of the sipes when the sipes are arranged at intervals, by arranging the sipes in a specific sparse and dense arrangement. However, the aim is only to utilize lower rigidity between sipes with a narrow spacing than between sipes with a wide spacing, and there is no mention of the use of rigidity between the sipes in the latter case, and there are no related studies. There is no mention of the idea.
（発明が解決しようとする課題）
タイヤの踏面パターンを構成する、例えばブロックと呼
ばれるような陸部区画が、サイプすなわちタイヤの接地
域内で溝壁の相互間の事実上の閉合を来す程に狭い幅の
切込み溝（以下この明細書で狭溝と呼ぶ。）によって細
分されることによるその細分化部分の剛性低下は、該部
分の曲げ変形に由来するエツジがタイヤのトラクション
及び制動の性能の改善に利用される一方で、このような
エツジに集中して作用するタイヤ荷重のために、局部的
な圧力上昇の下で氷結面又は凍結路面の融水が増し、却
ってトラクション、制動性能の低下を来す不利を適切に
回避し得る踏面パターンを提案することがこの発明の目
的である。(Problem to be Solved by the Invention) Land sections such as blocks, which constitute the tread pattern of a tire, are so large that the sipes, i.e., the groove walls are virtually closed to each other within the contact area of the tire. The decrease in rigidity of the subdivided portions due to the narrow cut grooves (hereinafter referred to as narrow grooves in this specification) is caused by the edges resulting from bending deformation of the portions, which impair the tire's traction and braking performance. However, due to the tire load concentrated on the edges, melt water on frozen surfaces or frozen road surfaces increases due to the local pressure increase, which actually impairs traction and braking performance. It is an object of the present invention to propose a tread pattern that can adequately avoid the disadvantages of deterioration.
（課題を解決するための手段）
この発明は走行地表面上を接地転動する踏面内で、踏面
のまわりに沿ってのびる複数の主溝又は、これらの主溝
とそれを横切る複数の副溝とにより相互区分された、互
いに分離独立する多数の陸部区画を有し、該区画の少な
くとも一部は、該区画をその相互区分溝の溝深さと同等
以下の溝深さで、溝幅ははるかに狭い少なくとも一本の
狭溝により細分された狭幅陸部をそなえて、狭溝の溝壁
に直交する向きに測った狭幅陸部の肉厚が狭溝の溝深さ
に対して０．１〜０．５倍の範囲内を占める曲げ変形領
域と、同じく狭溝から相互区分溝に至るまでの肉厚が狭
溝の溝深さに対して０．７８〜２．０７倍に相当するせ
ん断変形領域とより成るものとした、踏面パターンを具
備する氷結湿濡地表上での走行性能に優れる空気入りタ
イヤであり、陸部区画の少なくとも一部が二本以上の狭
溝により、一又は数個に細分した狭幅陸部をもつことま
た狭幅陸部が陸部区画の踏面上に、相互区分溝の溝深さ
の０．１倍以内で突出する高さをもつこととしても有用
である。(Means for Solving the Problem) This invention provides a plurality of main grooves extending along the circumference of the tread surface, or a plurality of sub grooves crossing the main grooves, within the tread surface that contacts the ground and rolls on the surface of the running ground. It has a large number of separate and independent land sections separated from each other by It has a narrow land section subdivided by at least one narrow groove that is much narrower, and the wall thickness of the narrow land section measured perpendicular to the groove wall of the narrow groove is relative to the groove depth of the narrow groove. The bending deformation region occupies a range of 0.1 to 0.5 times, and the wall thickness from the narrow groove to the mutually dividing groove is 0.78 to 2.07 times the groove depth of the narrow groove. A pneumatic tire with excellent running performance on frozen wet and wet ground, which has a tread pattern consisting of a corresponding shear deformation area, and at least a part of the land section has two or more narrow grooves, Having a narrow land section that is subdivided into one or several pieces, and having a height that projects above the tread of the land section by within 0.1 times the groove depth of the mutual dividing groove. is also useful.
すなわちこの発明では、陸部区画のうちの少なくとも一
部、実際上は大部又は全部について曲げ変形領域とせん
断変形領域とに分けることにより、前者の曲げ変形下に
おけるエツジ効果を、後者による際立って高い剛性（抗
曲げ変形）の下に接地酸接触面積を維持確保することに
よって、より有効に発揮するように役立て得る。That is, in this invention, by dividing at least a portion, in fact, most or all, of a land section into a bending deformation region and a shear deformation region, the edge effect under bending deformation of the former is significantly reduced by the latter. By ensuring that the ground acid contact area is maintained under high rigidity (resistance to bending deformation), it can be helped to perform more effectively.
第１図にこの発明による上記狭幅陸部に番号６を付しそ
の種々な配置の態様を例示し、また第２図に、この発明
に従う踏面パターンの一例を平面に展開した要部とその
Ａ−Ａ断面、さらに別例の断面で示し、図中１は踏面、
２は主溝、３は副溝、４は陸部区画、５は狭溝、そして
６は狭幅陸部であり、またＨは主溝２及び又は副溝３を
区分溝として一括してそのうちより深い方（通常は主溝
の方が深いか又は同等）の溝深さ、ｈは狭溝５の溝深さ
、Ｔ、は狭幅陸部６の肉厚、ＴＬは狭溝５から区分溝に
至るまでの肉厚である。In FIG. 1, the number 6 is attached to the narrow land portion according to the present invention, and various arrangements thereof are illustrated, and in FIG. It is shown in the A-A cross section and the cross section of another example, and 1 in the figure is a tread,
2 is the main groove, 3 is the minor groove, 4 is the land section, 5 is the narrow groove, and 6 is the narrow land section, and H is the main groove 2 and/or the minor groove 3 as a dividing groove. The groove depth of the deeper one (usually the main groove is deeper or the same), h is the groove depth of the narrow groove 5, T is the wall thickness of the narrow land portion 6, and TL is the division from the narrow groove 5. It is thick up to the groove.
なお第２図（Ｃ）にて狭幅区部６が踏面１より突出する
場合の例を示し、ｄはその突出の高さである。In addition, FIG. 2(C) shows an example where the narrow section 6 protrudes from the tread surface 1, and d is the height of the protrusion.
次に第３図には従来の踏面パターンの一例につき陸部区
画４′がほぼ等間隔配列の狭溝５′により細分された場
合を第２図に対応して示した。Next, FIG. 3 shows an example of a conventional tread pattern in which a land section 4' is subdivided by narrow grooves 5' arranged at approximately equal intervals, corresponding to FIG.
（作 用）
さて氷結面上における摩擦係数μに関して陸部区画４を
１つのブロックとしてこれが狭い溝５で細分化されたと
きの接地圧分布は第４図においてエツジ部ｅは高く、後
は均一にできるだけブロック全面が接地するのが望まし
いのは明らかである。(Function) Now, regarding the friction coefficient μ on the frozen surface, when the land section 4 is divided into one block by narrow grooves 5, the ground pressure distribution is high at the edge e and uniform afterward in Fig. 4. It is obvious that it is desirable that the entire surface of the block be grounded as much as possible.
図中■はタイヤの転がり移動の方向を示す。■ in the figure indicates the direction of rolling movement of the tire.
ブロックの接地圧分布はブロック形状により変えること
もできるが、もう１つの方法として、ブロックの変形に
より正分布を変えることもでき、例えば第５図（ａ）、
（ｂ）に示すように摩擦力Ｆによる変形を曲げ変形と
すればエツジ部ｅは立つのに対し、せん断変形とすれば
接地面の浮き上がりは生じない。The ground pressure distribution of the block can be changed by changing the shape of the block, but another method is to change the positive distribution by deforming the block. For example, as shown in Fig. 5(a),
As shown in (b), if the deformation caused by the frictional force F is a bending deformation, the edge portion e will stand up, whereas if it is a shear deformation, the ground plane will not rise.
ここで第６図のようなブロックモデルにて、Ｘ方向の力
がかかった場合のプロ・ンク剛性を日本機械学会績 機
械工学便覧、材料力学（上、下）（中原一部著養賢堂発
行）などの既知文献により求めると変形によるブロック
先端（接地部）での傾斜角をθとすると、
が与えられ、単位接地面積あたりの剪断力をｆとすると
、Ｆ＝ｆｂｔであるので、傾斜角θに対するブロック剛
性をＧとすると、
ｔ” ２
０式は曲げとせん断を含めた場合のブロック剛性であり
、曲げ剛性をＧｂ、せん新開性をＧｓとすると、
Ｅ
Ｇｓ＝□ ・・・■■〜■式
をブロック長ｔに対して表わすと第７図のようになり、
ブロック高さｈをコンスタント（１０ｍｍ）にすると、
ブロック長ｔを大きくしていくことで曲げ剛性は象、激
に大きくなり、（せん新開性は一定）変形様式としては
相対的にせん断変形になる。Here, using a block model as shown in Figure 6, we can calculate the rigidity when a force is applied in the If the inclination angle at the tip of the block (ground contact part) due to deformation is θ, then the following is given.If the shear force per unit ground contact area is f, then F=fbt, so the inclination is If the block rigidity with respect to the angle θ is G, then the formula t''20 is the block rigidity including bending and shearing, and if the bending rigidity is Gb and the shear patency is Gs, then E Gs=□ ・・・■ Expressing the formulas from ■ to ■ for the block length t is as shown in Figure 7,
When the block height h is constant (10 mm),
By increasing the block length t, the bending rigidity increases dramatically, and the deformation mode is relatively shear deformation (the shear deformability is constant).
以上より、ブロック高さｈを変えずにブロック変形を曲
げとせん断にコントロールするにはブロック長ｔを変え
るしかない。From the above, the only way to control block deformation in bending and shearing without changing block height h is to change block length t.
従って第４図においてエツジ部ｅは高く、後は均一にで
きるだけブロック全面が接地するような接地圧分布を得
るためには、エツジ部ｅを曲げ変形残り他の部分はせん
断変形とすれば良く、例えば第８図に示すようにエツジ
部ｅに薄いブロック、すなわち狭幅陸部６を配し、その
残余の部分は狭溝５をへだてて十分な長さを有するもの
とすることにより実現できる。Therefore, in Fig. 4, the edge part e is high, and in order to obtain a ground pressure distribution in which the entire block is in contact with the ground as uniformly as possible, the edge part e should be bent and deformed, and the other parts should be subjected to shear deformation. For example, as shown in FIG. 8, this can be realized by arranging a thin block, ie, a narrow land portion 6, at the edge portion e, and making the remaining portion have a sufficient length apart from the narrow groove 5.
そこで第８図のようなブロック端に薄ブロックを設けた
場合や、第９図のようなブロック中間部に薄ブロックを
作った場合等が具体的手法として考えられる。Therefore, concrete methods include the case where a thin block is provided at the end of the block as shown in FIG. 8, or the case where a thin block is formed at the middle part of the block as shown in FIG.
この発明では、狭幅陸部６の肉厚Ｔｓを狭溝５の溝深さ
ｈの０．１倍から０．５倍に限定する。このような狭幅
陸部６により細分した陸部区画４が氷結面上を摩擦する
と、狭幅陸部６のみは摩擦力により曲げ変形し、そのエ
ツジ部ｅが氷結面に押しつけられるため、氷表面をわず
かながら掻き削る。In this invention, the wall thickness Ts of the narrow land portion 6 is limited to 0.1 to 0.5 times the groove depth h of the narrow groove 5. When the land section 4 subdivided by such narrow land portions 6 rubs against the frozen surface, only the narrow land portion 6 bends and deforms due to the frictional force, and its edge e is pressed against the frozen surface. Scrape the surface slightly.
そして新たに現われた新鮮な氷表面上に曲げ剛性の大き
な残りの陸部区画が載り、この区画は曲げ変形が小さく
、陵部表面がほぼ均一に接地することになる。いうまで
もなく摩擦状態下での氷表面は融水が漂い、氷温も上昇
して摩擦係数が低下しているので、このような融水表面
層を除去することにより氷表面の摩擦係数を高め、その
上でほぼ均−に接地する陵部で摩擦することにより大き
なＷｌｌ方力得ることができる。ここに上記肉厚Ｔｓが
０．１ｈよりも薄いとその剛性が低下しすぎまた０、５
ｈより大きいとエッヂが立ちにりく、何れも氷表面を削
りとる効果が低下する。また、狭幅陸部６を陸部区画４
の表面より突出させると木表面層切削効果がより大きく
なる。しかし突出量が大きすぎると走行中に該突出部の
もげが発生するので突出量は主溝深さＨの０．１倍以下
でなければならない。The remaining land segment with high bending stiffness then rests on the newly appeared fresh ice surface, and this segment has small bending deformation and the ridge surface is in almost uniform contact with the ground. Needless to say, under frictional conditions, melt water drifts on the ice surface, and the ice temperature rises, reducing the friction coefficient. By removing this melt water surface layer, the friction coefficient of the ice surface can be reduced. A large Wll direction force can be obtained by raising the height and applying friction with the ridges that touch the ground almost evenly. Here, if the wall thickness Ts is thinner than 0.1h, the rigidity will be too low.
If it is larger than h, the edges will be difficult to stand up, and the effect of scraping the ice surface will be reduced. In addition, the narrow land section 6 is divided into the land section 4.
If it is made to protrude from the surface of the wood, the cutting effect of the wood surface layer will be greater. However, if the amount of protrusion is too large, the protrusion will peel off during running, so the amount of protrusion must be 0.1 times or less the depth H of the main groove.
ところで上記のように陸部区画４の曲げ剛性は陵部高さ
（溝深さＨ）と陵部厚さによって定まる（０式参照）と
ころ、第１０図のように陸部区画４を、踏面から狭溝５
の溝深さｈまでの表層部Ｓと、それに隣接した深さｈか
ら主溝深さＨまでの基底部Ｂとに分けて考えた時、基底
部Ｂは高さがＨ−ｈであるのに対し基底部Ｂの幅Ｔ、が
Ｈ−ｈの１．５倍以上であるので、曲げ剛性が非常に太
き（、この部分は殆ど曲げ変形しないと考えられ、この
ような場合、基底部Ｂの変形は無視できる。By the way, as mentioned above, the bending rigidity of the land section 4 is determined by the height of the ridge (groove depth H) and the thickness of the ridge (see formula 0). From narrow groove 5
When considering the surface layer S up to the groove depth h and the adjacent base section B from the depth h to the main groove depth H, the height of the base section B is H-h. On the other hand, since the width T of the base part B is more than 1.5 times H-h, the bending rigidity is very large (this part is considered to be hardly deformed by bending, and in such a case, the base part The deformation of B can be ignored.
狭溝５に隣接している陸部区画４はより大きな摩擦力を
発生させるために氷結面に対しできるだけ均一接地しな
ければならないのはすでに述べた。It has already been mentioned that the land section 4 adjacent to the narrow groove 5 must be in contact with the icy surface as uniformly as possible in order to generate a greater frictional force.
このためこの陸部区画４０部分は曲げ剛性が大きくなけ
ればならない。しかし、実際にはブロック剛性を大きく
するためＴ、を大きくしていくと、第１１図に示すよう
に均一接地はするものの氷表面には長さＴ、のブロック
が擦過する間に、その摩擦熱により水腹が発生し摩擦係
数の低下を来す。一方、Ｔ、を小さくしていくと、第１
２図に示すように、短いＴ、が榛遇する間には氷表面に
水膜の発生は殆どな（高い摩擦係数のままで摩擦するこ
とができるが一方でブロック剛性の低下によりブロック
がひしゃげ変形してブロックのエツジ部しか路面と接触
しなくなり、このためやはり摩擦係数が低下する。Therefore, this land section 40 portion must have high bending rigidity. However, when T is increased in order to increase the block rigidity, as shown in Figure 11, although the block of length T rubs against the ice surface, as shown in Figure 11, the friction Heat causes a water belly, which lowers the coefficient of friction. On the other hand, as T becomes smaller, the first
As shown in Figure 2, during the short T, almost no water film is formed on the ice surface (friction can be achieved with a high friction coefficient, but on the other hand, the block is crushed due to a decrease in block rigidity). Due to deformation, only the edges of the block come into contact with the road surface, which also reduces the coefficient of friction.
以上によりブロック幅Ｔ、には、ブロック高さ（サイプ
深さ）ｈに対して最適値が存在し、いまｈ＝１０ｍのと
きを仮定すると第１３図に示すようになる。As described above, there is an optimum value for the block width T with respect to the block height (sipe depth) h, and assuming that h=10 m, the value is as shown in FIG. 13.
すなわち、試験結果から第１３図に従い０．７８＜ＴＬ
／ｈ＜２．０７にて氷上μが最大値の９０％以上となる
ようなＴ１の範囲が与えられる。That is, according to the test results in Figure 13, 0.78<TL
A range of T1 is given in which the on-ice μ is 90% or more of the maximum value when /h<2.07.
以上をもとに氷結面上における摩擦係数が最大となるＴ
、について調べたところブロック剛性Ｇが大きく、かつ
、ブロックの厚さＴ、が小さい方が、即ち１／Ｔ、が大
きい方が氷上摩擦係数μが大きくなることがら■弐で定
まるブロック剛性に対してＧ／ＴＬが氷上摩擦係数μと
良く対応し、この鑑定は第１４図に示すとおりであるこ
とが判った。Based on the above, T at which the friction coefficient on the frozen surface is maximum
According to the investigation of It was found that G/TL corresponded well to the coefficient of friction on ice μ, and this evaluation was as shown in FIG.
このことから
・・・（４）
であるから、ゴムの種類によらずＴＬ ／（２ｈ” ＋
−ＴＬ”）が最大となるＴ、で、氷結面上摩擦係数μは
最大となる。From this, (4), regardless of the type of rubber, TL / (2h" +
-TL'') becomes maximum at T, the friction coefficient μ on the frozen surface becomes maximum.
そこでこれを微分し
０式がＯとなるＴＬが氷結面上摩擦係数μが最大となる
ＴＬであり、即ち、これをＴＬＭとするとｈ
が得られる。Then, by differentiating this, the TL at which the 0 equation becomes O is the TL at which the friction coefficient μ on the frozen surface becomes the maximum, that is, if this is set as TLM, h 2 is obtained.
ＴＬに対し、Ｇ／ＴＬ、即ち、ＴＬ ／ （２ｈ”÷３
／２ＴＬ”）は第１５図のようになり、最大値は、ＴＬ
＝ＴＬＭの時で、
ある。ここで、第１３図における試験結果においてもＴ
Ｌ＝ＴＬ、４付近で氷上μは最大となっている。For TL, G/TL, that is, TL / (2h”÷3
/2TL”) is as shown in Figure 15, and the maximum value is TL
= At the time of TLM, there is. Here, the test results in Figure 13 also show that T
The on-ice μ is at its maximum near L=TL, 4.
ＴＬを、Ｇ／ＴＬが最大値の９５％以上となる範囲に定
めると
Ｚ
よりＴＬの範囲は、
であるから、
０．８３６ｈ ＜ Ｔｔ ＜ １．５９５ｈ
・・・■の範囲とすることがより望ましい。If TL is set in a range where G/TL is 95% or more of the maximum value, the range of TL from Z is as follows: 0.836h < Tt < 1.595h
...It is more desirable to set it in the range of ■.
（実施例）
夫隻班上
タイヤサイズ１０．００Ｒ２０の供試タイヤを、第２図
ａ（適合例１〜１０）及び第２図ｄ（適合例１１〜１４
）にそれぞれ示したこの発明に従う踏面パターンと、第
３図に示す在来パターンとで対比される以外のタイヤ諸
元を共通に揃えて同一条件にて試作しサイズ ７．５０
ＶＸ２０のリムに組み内圧７．２５ｋｇ／ｃｍ”荷重２
７００ｋｇの条件で氷結面上における制動テストを行っ
た。(Example) Test tires with a tire size of 10.00R20 were shown in Figure 2 a (Compatible Examples 1 to 10) and Figure 2 d (Compatible Examples 11 to 14).
) The tread pattern according to the present invention shown in FIG. 3 and the conventional pattern shown in FIG.
Built on VX20 rim, internal pressure 7.25kg/cm” load 2
A braking test was conducted on an icy surface under the condition of 700 kg.
ここに区分溝の溝深さＨはすべて２０ｍｍ、狭溝につい
ては溝深さｈを１０ｍに揃えた。Here, the groove depth H of all the dividing grooves was set to 20 mm, and the groove depth h of the narrow grooves was set to 10 m.
制動テストは、氷温−５°Ｃ１時速２０ Ｋｍ／ｈでの
走行中に急ブレーキをかけ、停止位置までの滑走距離を
測定し、その逆数をとって、コントロールタイヤの成績
を１００とする指数表示にて氷上性能を比較した。結果
は表１に示す。In the braking test, sudden braking is applied while driving at 20 km/h at a freezing temperature of -5°C, the sliding distance to the stopping position is measured, and the reciprocal of the sliding distance is taken, and the performance of the control tire is determined as an index of 100. Performance on ice was compared as shown. The results are shown in Table 1.
ここで指数１００での制動距離は３２．８ｍであった。Here, the braking distance at an index of 100 was 32.8 m.
表１
実施例■
タイヤサイズ１７５／７０Ｒ１３の乗用車用タイヤにつ
いても実施例Ｉに準じる踏面パターン（置溝溝の溝深さ
Ｈはｌ Ｑ 、 ７ ｍｍ 、狭溝の溝深さｈを７．０
ｍｍ）にて、次のようにして氷上性能を比較した。Table 1 Example ■ A tread pattern according to Example I was also applied to a passenger car tire with a tire size of 175/70R13 (the groove depth H of the groove is lQ, 7 mm, and the groove depth h of the narrow groove is 7.0
The performance on ice was compared in the following manner.
１５００ｃｃクラスの乗用車に２．０ ｋｇ／ｃｍ”の
内圧に空気を充填した上記サイズの供試タイヤを装着し
前席２名乗車で速度４０ ）ａｎ ／ ｎからの制動テ
ストを行った。詳細は実施例■と同様である。結果を表
２にて示す。ここで指数１００での制動距離は５６ｍで
あった。A test tire of the above size filled with air to an internal pressure of 2.0 kg/cm was installed on a 1500cc class passenger car, and a braking test was conducted at a speed of 40)an/n with two people in the front seats.For details, see The same as in Example 2. The results are shown in Table 2. Here, the braking distance at an index of 100 was 56 m.
表２
なお乗用車用タイヤの場合には狭幅陸部の突出量ｄを０
．ＩＸＨより高くしても陵部もげは発生しなかったが０
．ＩＸＨより高くしても氷上性能の向上効果は格別みら
れないので、ｄは０．ＩＸＨ以内とすることがのぞまし
い。Table 2 In the case of passenger car tires, the protrusion amount d of the narrow land area is 0.
．． Even if it was higher than IXH, no bulging occurred on the ribs, but 0
．． Even if it is higher than IXH, there is no noticeable improvement in on-ice performance, so d is 0. It is desirable to keep it within IXH.
以上のべたところにおいて陸部区画の形状は概括的に長
方形で模式的にあられしたが実際の適用は第１６図に数
例を図解したような、種々な形状を任意選択でき、この
ような場合の採寸の要領は図に併示したとおりである。In the above, the shape of the land division is generally rectangular, but in actual application, various shapes can be arbitrarily selected, some examples of which are illustrated in Figure 16. The procedure for measuring is shown in the figure.
（発明の効果）
この発明によれば、踏面パターンを構成する陸部区画に
つき、その氷上性能の有効な改善に寄与するための融水
排除機能と、氷結面との間のＷｌｌ方力確保機能とをそ
れぞれ分担する、曲げ変形領域とせん断変形領域とから
なるものとして、より確実な、氷結湿濡地表上での走行
性能の向上を実現することができる。(Effects of the Invention) According to the present invention, the land section constituting the tread pattern has a melt water removal function that contributes to effective improvement of its performance on ice, and a function that ensures a Wll direction force between it and the frozen surface. By forming a bending deformation region and a shearing deformation region which share the same functions, it is possible to more reliably improve running performance on a frozen wet ground surface.
第１図はこの発明に従う陸部区画の細分要領を示す説明
図、
第２図は踏面パターンの一例を示す展開口と断面図、
第３図は従来パターンの展開図であり、第４図は陵部素
子の断面図、
第５図は曲げ及びせん断変形比較図、
第６図はブロックモデル図、
第７図はブロック長さに対する剛性の変化を示すグラフ
、
第８図、第９図は曲げとせん断の複合をたらす陸部区画
の説明図、
第１０図は変形挙動の説明図、
第１１図、第１２図は剪断変形領域肉厚の作用説明図で
あり、
第１３図はブロンク厚さＴＬと、氷結面上の摩擦係数μ
との関係グラフ、
第１４図はＧ／ＴＬとμとの関係グラフ、第１５図はＴ
ＬとＴＬ／（２ｈ”＋３／２ＴＬジとの関係グラフ、第
１６図は陸部区画の展開形状を例示する説明図である。
■・・・踏面 ２・・・主溝３・・・副溝
４・・・陸部区画５・・・狭溝
６・・・狭幅陸部特許出願人 株式会社 ブリ
デストン代理人 弁理士 杉 村 暁 査問
弁理士 杉 村 興 作問
弁理士 佐 藤 安 捻回 弁理士
冨 １） 典同 弁理士 梅
本 政 大同 弁理士 仁 平
孝第１図
（３）（ｂ）
（Ｃ）
第２図
（ａ）
（ｂ）（Ｃ）
（ｄ）
第３図
＠４図
第５図
（ａ） （ｂ）
一一−Ｆ −一−Ｆ第６図
賽杆！：ｂ
第８図 第９図
第１Ｏ図
第１１図 第１２図
サイゴ間Ｐ小瓜１１場・合 サイプ
ｌｉｌ’ｌ隔狽１琲今第１３図
ブロック１１ Ｔｒ、（ｍｍ＞
第１４図
第１５図
ＴＬ （ｍｍン
（ａ）
（ｄ）
＠１６図
（ｂ） （Ｃ）
（ｅ）Fig. 1 is an explanatory diagram showing how to subdivide land sections according to the present invention, Fig. 2 is a development opening and cross-sectional view showing an example of a tread pattern, Fig. 3 is a development view of a conventional pattern, and Fig. 4 is Figure 5 is a comparison diagram of bending and shear deformation, Figure 6 is a block model diagram, Figure 7 is a graph showing changes in rigidity with block length, Figures 8 and 9 are bending diagrams. Figure 10 is an illustration of the deformation behavior, Figures 11 and 12 are illustrations of the effect of the wall thickness in the shear deformation region, and Figure 13 is the bronch thickness. TL and the coefficient of friction μ on the frozen surface
Figure 14 is a graph of the relationship between G/TL and μ, Figure 15 is the graph of the relationship between T
The relationship graph between L and TL/(2h"+3/2TLji, FIG. 16 is an explanatory diagram illustrating the developed shape of the land section. ■...Tread 2...Main groove 3...Sub. Groove 4...Land section 5...Narrow groove
6... Narrow land area patent applicant Brideston Co., Ltd. Agent Patent attorney Akira Sugimura Interviewer
Written by patent attorney Oki Sugimura
Patent Attorney Yasushi Sato Patent Attorney
Tomi 1) Norido Patent Attorney Ume
Honmasa Daido Patent Attorney Nipei
Takashi Figure 1 (3) (b) (C) Figure 2 (a) (b) (C) (d) Figure 3 @ Figure 4 Figure 5 (a) (b) 11-F -1- F Figure 6 dice! :b Fig. 8 Fig. 9 Fig. 1O Fig. 11 Fig. 12 Fig. 12 Between Saigo Figure TL (mm (a) (d) @16 Figure (b) (C) (e)
Claims (1)
りに沿ってのびる複数の主溝又は、これらの主溝とそれ
を横切る複数の副溝とにより相互区分された、互いに分
離独立する多数の陸部区画を有し、該区画の少なくとも
一部は、該区画をその相互区分溝の溝深さと同等以下の
溝深さで、溝幅ははるかに狭い少なくとも一本の狭溝に
より細分された狭幅陸部をそなえて、狭溝の溝壁に直交
する向きに測った狭幅陸部の肉厚が狭溝の溝深さに対し
て０．１〜０．５倍の範囲内を占める曲げ変形領域と、
同じく狭溝から相互区分溝に至るまでの肉厚が狭溝の溝
深さに対して０．７８〜２．０７倍に相当するせん断変
形領域とより成るものとした、踏面パターンを具備する
氷結湿濡地表上での走行性能に優れる空気入りタイヤ。 ２、請求項１において、陸部区画の少なくとも一部が二
本以上の狭溝により、一又は数個に細分した狭幅陸部を
もつ、氷結湿濡地表上での走行性能に優れる空気入りタ
イヤ。 ３、請求項１又は２において狭幅陸部が陸部区画の踏面
上に、相互区分溝の溝深さの０．１倍以内で突出する高
さをもつ、氷結湿濡地表上での走行性能に優れる空気入
りタイヤ。[Scope of Claims] 1. A tread that contacts the ground and rolls on the surface of the running ground, which is mutually separated by a plurality of main grooves extending around the tread, or by these main grooves and a plurality of sub-grooves that cross them. It has a large number of mutually separated land sections, at least some of which have groove depths equal to or less than the groove depths of the mutually dividing grooves, and groove widths that are at least much narrower. It has a narrow land section subdivided by one narrow groove, and the wall thickness of the narrow land section measured perpendicular to the groove wall of the narrow groove is 0.1 to 0.1 to the groove depth of the narrow groove. A bending deformation area occupying a range of 0.5 times,
Similarly, the icing includes a tread pattern consisting of a shear deformation region whose wall thickness from the narrow groove to the mutually dividing groove is 0.78 to 2.07 times the groove depth of the narrow groove. Pneumatic tires with excellent running performance on wet surfaces. 2. According to claim 1, the air chamber has a narrow land section in which at least a part of the land section is subdivided into one or several pieces by two or more narrow grooves, and has excellent running performance on a frozen wet ground surface. tire. 3. In claim 1 or 2, the narrow land portion has a height that projects above the tread of the land section by within 0.1 times the groove depth of the mutual dividing groove, and the vehicle is traveling on a frozen wet ground surface. Pneumatic tires with excellent performance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2307297A JP2693637B2 (en) | 1990-11-15 | 1990-11-15 | Pneumatic tire with excellent running performance on icy and wet surfaces |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2307297A JP2693637B2 (en) | 1990-11-15 | 1990-11-15 | Pneumatic tire with excellent running performance on icy and wet surfaces |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04183611A true JPH04183611A (en) | 1992-06-30 |
| JP2693637B2 JP2693637B2 (en) | 1997-12-24 |
Family
ID=17967446
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2307297A Expired - Lifetime JP2693637B2 (en) | 1990-11-15 | 1990-11-15 | Pneumatic tire with excellent running performance on icy and wet surfaces |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2693637B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5385189A (en) * | 1991-11-01 | 1995-01-31 | Bridgestone Corporation | Pneumatic tire with paired sides in the tread |
| JP2001199206A (en) * | 1999-11-10 | 2001-07-24 | Ohtsu Tire & Rubber Co Ltd :The | Pneumatic radial tire |
| JP2006160158A (en) * | 2004-12-09 | 2006-06-22 | Bridgestone Corp | Pneumatic tire |
| JP2016112993A (en) * | 2014-12-12 | 2016-06-23 | 住友ゴム工業株式会社 | Pneumatic tire |
| JP2020179744A (en) * | 2019-04-24 | 2020-11-05 | 住友ゴム工業株式会社 | tire |
-
1990
- 1990-11-15 JP JP2307297A patent/JP2693637B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5385189A (en) * | 1991-11-01 | 1995-01-31 | Bridgestone Corporation | Pneumatic tire with paired sides in the tread |
| JP2001199206A (en) * | 1999-11-10 | 2001-07-24 | Ohtsu Tire & Rubber Co Ltd :The | Pneumatic radial tire |
| JP4573984B2 (en) * | 1999-11-10 | 2010-11-04 | 住友ゴム工業株式会社 | Pneumatic radial tire |
| JP2006160158A (en) * | 2004-12-09 | 2006-06-22 | Bridgestone Corp | Pneumatic tire |
| JP4658579B2 (en) * | 2004-12-09 | 2011-03-23 | 株式会社ブリヂストン | Pneumatic tire |
| JP2016112993A (en) * | 2014-12-12 | 2016-06-23 | 住友ゴム工業株式会社 | Pneumatic tire |
| JP2020179744A (en) * | 2019-04-24 | 2020-11-05 | 住友ゴム工業株式会社 | tire |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2693637B2 (en) | 1997-12-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4942167B2 (en) | Pneumatic tire | |
| US8544512B2 (en) | Pneumatic tire with tread having sipe | |
| US20050150581A1 (en) | Pneumatic tire | |
| US20090165911A1 (en) | Pneumatic tire | |
| JPH07172112A (en) | Pneumatic tire | |
| JPH082215A (en) | Pneumatic tire | |
| US5711828A (en) | Pneumatic tires | |
| JP4650100B2 (en) | Pneumatic tire | |
| JP3519474B2 (en) | Pneumatic tire suitable for running on ice and snow | |
| JPH0994829A (en) | Vulcanization molding mold and pneumatic tire produced using the same | |
| JP3273772B2 (en) | studless tire | |
| US8181683B2 (en) | Pneumatic tire with tread having upper surface sipes and wall surface sipes | |
| JP2007137110A (en) | Pneumatic tire | |
| JP3586045B2 (en) | Studless pneumatic tires | |
| US8132605B2 (en) | Pneumatic tire with tread including block having sipes | |
| JP4306847B2 (en) | Pneumatic tire | |
| JPH04183611A (en) | Pneumatic tire excellent in traveling performance on frozen wet ground surface | |
| JP3273771B2 (en) | Pneumatic tire | |
| JP3656731B2 (en) | Pneumatic tire | |
| JPH09164815A (en) | Studless pneumatic tire | |
| JP3711687B2 (en) | Pneumatic radial tire | |
| JPH11180116A (en) | Pneumatic tire | |
| JPH04201609A (en) | Pneumatic tire excellent in running performance on frozen and wet ground surface | |
| JPH04215505A (en) | Pneumatic tire excellent in driveability on surface of frozen wetted ground | |
| JP4094168B2 (en) | Pneumatic radial tire |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19970805 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080905 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080905 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090905 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090905 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100905 Year of fee payment: 13 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100905 Year of fee payment: 13 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110905 Year of fee payment: 14 |
|
| EXPY | Cancellation because of completion of term | ||
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110905 Year of fee payment: 14 |