CN106956550A - Pneumatic tire - Google Patents

Abstract

The present invention provides a kind of core for not only preventing tyre bead and got rusty, and reaches the pneumatic tire for improving endurance quality.The pneumatic tire includes：Inner liner, chafer, clinch, core and protective layer.Protective layer is engaged with the end of inner liner, and positioned between core and chafer.Protective layer has：First end, it is located at the bonding part between protective layer and inner liner；Second end, it is located on the inside of the radial direction of core.The bottom surface of core is along substantially axial extension.In the axial direction, the second end is located between the medial extremity of bottom surface and the outboard end of the bottom surface.Rubber composition for protective layer includes matrix material rubber, and the matrix material rubber bag contains butyl rubber.The ratio of butyl rubber and matrix material rubber total amount is below the mass % of more than 65 mass % 90.

Description

Pneumatic tire

Technical field

The present invention relates to a kind of pneumatic tire.Specifically, it is arranged on the present invention relates to one kind on bus, truck etc. Pneumatic tire for heavy load.

Background technology

Inner liner is provided with tire.The inner liner is located at the inner side of tire, plays a part of for keeping internal pressure.

Inner liner is made up of the crosslinking rubber generated using rubber composition.The rubber composition of inner liner is used as matrix material Material rubber generally includes butyl rubber.And the rubber that butyl rubber is difficult to pass through as gases such as air is well known.

Tire is combined by multiple rubber components and constituted.Therefore the adhesive property of each rubber components is more important.Fourth Base rubber not only facilitates air-tightness, i.e. leak resistance energy, and can influence adhesive property.Inner liner comprising the butyl rubber is deposited The problem of being difficult to engage with other rubber.Various researchs have been carried out for this engagement to the inner liner.And by JP 2008- No. 126745 publications disclose an example of the research.

Patent document 1：Japanese Unexamined Patent Publication 2008-126745 publications

The content of the invention

When assembling tire to wheel rim, the bead part of tire can be placed on the bcad seats of wheel rim.When into tire When portion fills air, the bead part can be slided along bcad seats towards axially external.The flange of the bead part and wheel rim connects Touch.Thus, assembling of the tire to wheel rim is completed.

Heavy duty tire is configured to relative to axially inclined wheel rim using bcad seats sometimes.The bcad seats of the wheel rim Angle of inclination be usually 15 °.When assembling tire to the wheel rim, the prenex part of the tire can float from bcad seats.Due to It is formed with gap between tire and bcad seats, therefore during moisture or oxygen may penetrate into tire from the gap.

Core is provided with the bead part of tire.Core is usually using steel wire.Therefore, when moisture is isotonic fashionable, core may be made Get rusty.There is casing ply in bead part.The body cord of the casing ply of heavy duty tire is usually using all-steel cord.Cause This is isotonic fashionable when moisture, may also be got rusty on the body cord.

In order to prevent getting rusty, as long as penetrating into position configuration inner liner in gas.But as it was previously stated, inner liner is bonded Poor-performing.Therefore, different according to the configuration position of inner liner, inner liner may be peeled off., should in the manufacturing process of tire Stripping can influence productivity ratio.Moreover, the stripping can influence the endurance quality of tire.

Not only prevent that bead core from getting rusty it is an object of the invention to provide one kind, and reach the inflation for improving endurance quality Tire.

The pneumatic tire of the present invention includes：Inner liner, it is used to keep internal pressure；Chafer, it is placed in the tyre bead of wheel rim On seat；Clinch, its flange contact with the wheel rim；Core, it is located on the outside of the radial direction of the chafer；Protective layer, its Engaged with the end of the inner liner, and positioned between the core and the chafer, the protective layer has：First end, its Bonding part between the protective layer and the inner liner；Second end, it is located on the inside of the radial direction of the core.Institute Core is stated including the bottom surface opposed with the bcad seats when the tire is assembled on the wheel rim, along containing the tire centerline On the tire profile of the plane of axle, the bottom surface is along substantially axial extension.In the axial direction, second end is located at the bottom surface Medial extremity and the bottom surface outboard end between.The crosslinking rubber that the protective layer is generated by rubber composition is constituted.The rubber Glue constituent includes matrix material rubber, and described matrix material rubber includes butyl rubber.The butyl rubber and described matrix The ratio of material rubber total amount is below the mass % of more than 65 mass % 90.

It is preferred that, the thickness of the protective layer of the pneumatic tire is more than 0.4mm below 1.5mm.

It is preferred that, axially inner side end of the first end than the core of the pneumatic tire is by the outside of radial direction.It is more excellent The axially inner side end of the core selected from the pneumatic tire to the first end radial direction distance for more than 3mm 15mm with Under.

It is preferred that, in the pneumatic tire, the ratio of the thickness of the thickness of the protective layer and the bonding part is 50% Below the above 90%.

It is preferred that, engage with the end of inner liner the including of the pneumatic tire, and be located at protective layer between core and chafer. Protective layer has：First end, it is located at the bonding part between protective layer and inner liner；With the second end, it is located at the radius of core On the inside of direction.

In the pneumatic tire, the crosslinking rubber that protective layer is generated by rubber composition is constituted.The rubber composition is included Matrix material rubber, the matrix material rubber bag contains butyl rubber.The protective layer contributes to leak resistance energy.

Second end of the protective layer in the tire is located between the medial extremity of core bottom surface and the outboard end of the bottom surface.And at this Tire is assembled into the state of wheel rim, and even in being formed with gap between tire and wheel rim, protective layer is also arranged between this Gap is overlapping.Because protective layer includes butyl rubber, therefore you can suppress moisture or oxygen and penetrate into tire from the gap.So as to prevent Got rusty in the core of the tire.

In the tire, suitably adjustment is included in the amount of the butyl rubber in the rubber composition for protective layer.Should Protective layer is not only also reliably engaged with inner liner with chafer.In other words, the protective layer helps to prevent inner liner and anti- The stripping of rubber.So as to prevent the stripping of inner liner or chafer using in the tire as the damage of reason.Make the wheel mold There is excellent endurance quality.

The tire does not damage leak resistance energy, not only prevents from getting rusty in core, and reaches raising endurance quality.According to this hair Bright results in not only prevent that bead core from getting rusty, and reaches the pneumatic tire for improving endurance quality.

Brief description of the drawings

Fig. 1 is for the part sectioned view for the pneumatic tire for representing an embodiment of the invention.

Fig. 2 is the amplification profile local for representing the tire in Fig. 1.

The explanation of reference

2 ... tires

4 ... tyre surfaces

6 ... sidewalls

8 ... clinch

10 ... chafers

12 ... tyre beads

14 ... carcasses

18 ... inner liners

24 ... protective layers

24a ... the first noumenons

The bodies of 24b ... second

30 ... cores

32 ... triangle rubbers

38 ... casing plies

40 ... principal parts

42 ... reflex parts

The end of 48 ... inner liners 18

The toe-in of 52 ... tires 2

54 ... wheel rims

58 ... bcad seats

60 ... flanges

The bottom surface of 62 ... cores 30

64 ... first ends

66 ... second ends

Embodiment

Below, suitably referring to the drawings and based on preferred embodiment, the present invention is described in detail.

Fig. 1 represents pneumatic tire 2.Specifically, the Fig. 1 is represented along plane, the wheel comprising the central shaft of tire 2 The part section of tire 2.Above-below direction in the Fig. 1 is the radial direction of tire 2, and left and right directions is the axial direction of tire 2, with paper Vertical direction is the circumference of tire 2.Chain-dotted line CL in Fig. 1 represents the equatorial plane of tire 2.Remove beyond tread contour, should The shape of tire 2 is symmetrical relative to the equatorial plane.

The tire 2 includes：Tyre surface 4, a pair of sidewall 6, a pair of clinch 8, a pair of chafers 10, a pair of bead 12, carcasses 14th, belt 16, inner liner 18, separation layer 20, a pair of fillers 22 and a pair of protective layers 24.The tire 2 is tubeless tyre.Should Tire 2 is arranged on truck, bus etc..The tire 2 is heavy duty tire.

Tyre surface 4 is towards convex on the outside of radial direction.Tyre surface 4 forms the tread surface 26 for being contacted with road surface.In tire Ditch 28 is carved with face 4.Utilize the ditch 28 formation tread contour.The tyre surface 4 is made up of crosslinking rubber.In the tyre surface 4, it is considered to resistance to Grind performance, heat resistance and creep-resistant property.

Sidewall 6 extends from the end of tyre surface 4 towards radial direction substantially inner side respectively.The sidewall 6 is located at the axial direction of carcass 14 Outside.The sidewall 6 is made up of the crosslinking rubber with excellent belt cutting-resisting property and ageing-resistant performance.The sidewall 6 prevents carcass 14 Damage.

Each clinch 8 is located substantially at the radial direction substantially inner side on sidewall 6.Clinch 8 is presented axially in the He of tyre bead 12 The outside of carcass 14.Clinch 8 is made up of the crosslinking rubber with good wear performance.

Chafer 10 is located at the vicinity of tyre bead 12 respectively.Chafer 10 in the tire 2 is from the end of clinch 8 towards axially Substantially inner side extends.The chafer 10 can also be integrally formed with clinch 8.The material of chafer 10 and the material of clinch 8 It is identical.

Tyre bead 12 is located at the axially inner side of clinch 8 respectively.Tyre bead 12 includes core 30 and triangle rubber 32.

Core 30 is located on the outside of the radial direction of chafer 10.Core 30 is ring-type.Core 30 includes the non-telescoping metal of winding Silk.Specifically, the beam 34 being made up of the non-telescoping wire by winding is covered by packaging rubber 36, constitutes the core 30. The typical material of the wire is steel.

Triangle rubber 32 extends from core 30 towards radial direction outside.As shown in figure 1, triangle rubber 32 is towards on the outside of radial direction For tip.Triangle rubber 32 is made up of the crosslinking rubber of high rigidity.

Carcass 14 includes casing ply 38.Carcass 14 in the tire 2 is made up of one piece of casing ply 38.The carcass 14 can also It is made up of more than two pieces of casing ply 38.

Casing ply 38 in the tire 2 is erected between the tyre bead 12 of both sides, and along tyre surface 4, sidewall 6 and clinch 8 Inner side.Casing ply 38 turns back around core 30 from axially inner side towards outside.Turned back by this, principal part is formed in casing ply 38 40 and reflex part 42.The casing ply 38 includes principal part 40 and reflex part 42.

Although not shown, casing ply 38 is made up of a plurality of cord and rubberizing rubber arranged side by side respectively.Cord respectively with equator The absolute value of face angulation is 75 ° to 90 °.In other words, the carcass 14 has meridian cable architecture.The material of cord is steel. The casing ply 38 includes all-steel cord.

In the tire 2, the end of reflex part 42 is located on radial direction and between the outboard end and core 30 of triangle rubber 32. As it was previously stated, the tire 2 is installed on truck, bus etc..There is larger load in the partial action of the tyre bead 12 of the tire 2 Lotus.There is the tendency that strain is concentrated in the end of the reflex part 42.Intermediate layer 44 is additionally provided with the part of tyre bead 12 of the tire 2 With band 46.These parts suppress strain and concentrated to the end of reflex part 42.

Belt 16 is located on the inside of the radial direction of tyre surface 4.Belt 16 is laminated with carcass 14.Belt 16 strengthens carcass 14.Belt 16 in the tire 2 is made up of first layer 16a, second layer 16b, third layer 16c and the 4th layer of 16d.The tire 2 In belt 16 constituted by 4 layers.The belt 16 can both be constituted by 3 layers, can also be constituted by 2 layers.

As shown in figure 1, in the axial direction of the tire 2, for the first layer 16a for constituting belt 16, second layer 16b, In third layer 16c and the 4th layer of 16d, second layer 16b has maximum width.And it is in tire 2, for constituting band beam There is the layer of maximum axial width, i.e. second layer 16b end is the end of belt 16 in multiple layers of layer 16.In the wheel In tire 2, the axial width of belt 16 is represented with second layer 16b axial width.It is preferred that, the axial width of belt 16 is wheel More than 0.7 times of the Breadth Maximum of tire 2.

Although not shown, first layer 16a, second layer 16b, third layer 16c and the 4th layer of 16d are respectively by a plurality of curtain arranged side by side Line and rubberizing rubber are constituted.The material of cord is respectively steel.The belt 16 includes all-steel cord.Layer in cord respectively with it is red Road face is tilted.The absolute value of the cord and equatorial plane angulation is respectively 12 °~70 °.

Inner liner 18 is located at the inner side of carcass 14.Inner liner 18 is engaged via separation layer 20 with the inner surface of carcass 14.It is interior Lining 18 is made up of the crosslinking rubber with excellent air-tightness.The typical substrates material rubber of inner liner 18 be butyl rubber or Halogenated butyl rubber.Inner liner 18 keeps the internal pressure of tire 2.In other words, inner liner 18 contributes to the leak resistance energy of tire 2. The end 48 of inner liner 18 in the tire 2 is than core 30 by the inside of radial direction.Thus, it reliably ensure that the internal pressure of inner liner 18 Keep effect.

Separation layer 20 is clamped between carcass 14 and inner liner 18.Separation layer 20 is by the crosslinking rubber with excellent adhesive performance Glue is constituted.Separation layer 20 is not only firmly engaged with carcass 14, is also firmly engaged with inner liner 18.Separation layer 20 prevents liner Layer 18 is peeled off from carcass 14.

Filler 22 is located at the vicinity of tyre bead 12 respectively.Filler 22 is laminated with carcass 14.Filler 22 is in the radius side of carcass 14 To inner side, the core 30 around tyre bead 12 turns back.Although not shown, filler 22 is made up of a plurality of cord arranged side by side and rubberizing rubber. Cord is respectively relative to radial direction inclination.The material of cord is steel.The part that filler 22 suppresses tyre bead 12 is toppled over.The filler 22 Contribute to the endurance quality of tire 2.In the tire 2, the end of filler 22 is covered by rubber-coated 50.

Protective layer 24 is located at prenex 52 part of tire 2 respectively.As shown in figure 1, section of the protective layer 24 in the tire 2 Upper is in L-shaped.The protective layer 24 by using the part of toe-in 52 for starting point towards extend on the outside of radial direction part (below also by Referred to as the first noumenon 24a) and constitute towards the part (below also referred to as the second body 24b) of approximately axially outside extension.

The crosslinking rubber that protective layer 24 in the tire 2 is generated by rubber composition is constituted.And the rubber composition bag Rubber containing matrix material.The main component of matrix material rubber in the tire 2 is butyl rubber.In other words, the matrix material Expect that the main component of rubber includes butyl rubber.

In addition to butyl rubber, matrix material rubber in the tire 2 include as natural rubber, natural man-made rubber and Other rubber of ethylene propylene diene rubber etc..Viewpoint based on adherence, preferably natural rubber are used as other rubber.

Rubber composition for protective layer 24 includes reinforcing agent.Typical reinforcing agent is carbon black.Can use FEF, GPF, HAF, ISAF, SAF etc..The amount of the viewpoint of intensity based on protective layer 24, preferably carbon black is relative to matrix material rubber 100 Quality Mgmt Dept is more than 5 Quality Mgmt Dept, more than more preferably 10 Quality Mgmt Dept.Soft viewpoint based on protective layer 24, preferably carbon black Amount for below 70 Quality Mgmt Dept, below more preferably 60 Quality Mgmt Dept.Silica, Huo Zheyong can also be used together with carbon black Silica replaces carbon black.At this point it is possible to use dry type silica and wet silicon dioxide.

Rubber composition for protective layer 24 can also include filler, softening agent, sticker, sulphur in addition to reinforcing agent The medicines such as crosslinking agent, vulcanization accelerator, crosslinking coagent, the age resister of sulphur etc..By considering the processability and performance of tire 2, The rubber composition is made into most suitable amount with most suitable medicine.

Fig. 2 represents the part of tyre bead 12 of the tire 2 in Fig. 1.Above-below direction in the Fig. 2 is the radial direction of tire 2, left Right direction is the axial direction of tire 2, and the direction vertical with paper is the circumference of tire 2.

Fig. 2 also shows that the wheel rim 54 for being assembled with the tire 2.The wheel rim 54 is regular wheel rim.Tire 2 is assembled in wheel rim 54 On, and air is filled with tire 2, to press to regular internal pressure in tire 2.

Regular wheel rim in this specification refers to the defined wheel rim by the specification of 2 foundations of tire.For example, JATMA is advised In " standard rim " in lattice, TRA specifications " in Design Rim " and ETRTO specifications " Measuring Rim " is just Gauge wheel rim.

Regular internal pressure in this specification refers to the specification of 2 foundations of tire and defined internal pressure.In JATMA specifications " TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES " in " highest air pressure ", TRA specifications Record " maximum " and ETRTO specifications in " INFLATION PRESSURE " be regular internal pressure.

In this manual unless otherwise stated, the size and angle of all parts of tire 2 are assembled in just in tire 2 On gauge wheel rim, and air is filled so as to as being measured in the state of regular internal pressure to tire 2.When determining not to tire 2 apply load.In addition, when for riding tire for vehicles 2, determining size and angle in the state of internal pressure is 180kPa sometimes.

Wheel rim 54 possesses a pair of fitting portions 56.The tyre bead 12 of tire 2 is local to be entrenched in fitting portion 56 respectively.Fitting portion 56 Possess bcad seats 58 and flange 60.The chafer 10 of the tire 2 is placed on bcad seats 58.The overlap joint of flange 60 and the tire 2 Portion 8 is contacted.

The bcad seats 58 in wheel rim 54 shown in Fig. 2 is relative to axially inclined.The angle of inclination of the bcad seats 58 generally quilt It is set as 15 °.The wheel rim 54 that the angle of inclination of bcad seats 58 is set to 15 ° is also referred to as 15 ° of taper wheel rims.The angle of inclination Represented with the angle of inclination in the face of the side of chafer 10 of bcad seats 58.

The section of the core 30 of tyre bead 12 in the tire 2 is in hexagon.The section of the core 30 has six corners.In order to just In the explanation present invention, symbol a, b, c, d, e and f are paid into these corners in fig. 2.The corner b of the core 30 is the axle of the core 30 To medial extremity.

In the tire 2, for connecting the bottom surface 62 that corner a and corner f face are core 30.The bottom surface 62 and bcad seats 58 It is opposed.When the tire 2 is assembled on wheel rim 54, the core 30 of the tire 2 includes the bottom surface opposed with the bcad seats 58 of wheel rim 54 62.Plane of the section of the tire 2 shown in Fig. 2 along the central shaft for including the tire 2., should in the section of the tire 2 Bottom surface 62 is along substantially axial extension.Corner a is the axially inner side end of the bottom surface 62, and corner f is axially external for the bottom surface 62 End.

In fig. 2, symbol CE represents one end of the contact surface between tire 2 and wheel rim 54.As shown in Fig. 2 in the axial direction, In than end CE parts in the inner part, tire 2 is not contacted with wheel rim 54.The part of axially inner side is being leaned on than end CE and is being taken turns Gap is formed between tire 2 and wheel rim 54.

As shown in Fig. 2 in the axial direction, the end CE of contact surface position and the corner a of core 30 position is substantially uniform.Change sentence Talk about, be assembled into the tire 2 on wheel rim 54, and fill air so as in the state of as regular internal pressure, the end CE of contact surface Formed in the axial direction and in position corresponding with the corner a of core 30.

Protective layer 24 in the tire 2 is in the part (i.e. the first noumenon 24a) of its first end 64 and the end of inner liner 18 48 part engagement.The part (that is, the second body 24b) at the second end 66 of the protective layer 24 is located on radial direction and in core 30 Between chafer 10.That is, the local engagement of the end 48 of the tire 2 and inner liner 18, and possess positioned at core 30 with Protective layer 24 between chafer 10.Therefore, the protective layer 24 has be located at its bonding part between inner liner 18 the One end 64 and the second end 66 on the inside of the radial direction of core 30.

In tire 2, the second body 24b of protective layer 24 from the part of the toe-in 52 of tire 2 along bcad seats 58 simultaneously Towards the extension of substantially axial outside.Second end 66 of protective layer 24 is located at medial extremity a and the bottom surface 62 of the bottom surface 62 of core 30 Between outboard end f.The tire 2 is configured as, and gap as shown in Figure 2 is formed in the state of being assembled on wheel rim 54, Protective layer 24 is overlapping with the gap.As it was previously stated, the rubber composition for protective layer 24 includes fourth as matrix material rubber Base rubber.The protective layer 24 suppresses moisture or oxygen and penetrates into tire 2 from gap.So as to prevent that the core 30 of the tire 2 from getting rusty.

Casing ply 38 and filler 22 are configured between protective layer 24 and core 30 in the tire 2.As it was previously stated, casing ply 38 and filler 22 respectively include all-steel cord.The protective layer 24 of the tire 2 prevents the cord and filler included in casing ply 38 22 cords included get rusty.

In the tire 2, for the butyl rubber in the rubber composition of protective layer 24 and matrix material rubber total amount Ratio is more than 60 mass %.The protective layer 24 contributes to leak resistance energy.As it was previously stated, in the tire 2, the allusion quotation of inner liner 18 Mold base material rubber is butyl rubber or halogenated butyl rubber.Therefore, the protective layer 24 being made up of the rubber composition can Engaged by ground with inner liner 18.Viewpoint based on leak resistance energy and reliable adherence, the preferably ratio are more than 70 mass %.

For example, removing beyond inner liner 18, protective layer 24 is also engaged with chafer 10 and separation layer 20.Such as natural rubber The thin rubber of alkadienes is mainly used in the matrix material rubber of chafer 10 and separation layer 20.Therefore, when matrix material rubber contains During excessive butyl rubber, the adhesive performance of protective layer 24 and these parts can be damaged.

In the tire 2, for the butyl rubber in the rubber composition of protective layer 24 and matrix material rubber total amount Ratio is below 90 mass %.The protective layer 24 not only reliably connects with inner liner 18 but also with chafer 10 and separation layer 20 Close.Based on the viewpoint, the preferably ratio is below 85 mass %.

As described above, in the tire 2, the amount for the butyl rubber contained by the rubber composition of protective layer 24 is fitted Locality adjustment.So that the protective layer 24 has the air-tightness being mutually equal to inner liner 18.It is anti-so as to reach raising in the tire 2 Leak performance.And the protective layer 24 is not only reliably engaged with inner liner 18 but also with chafer 10.In other words, the protective layer 24 help to prevent the stripping of inner liner 18 and chafer 10.So as to be prevented in the tire 2 with inner liner 18 and chafer 10 Stripping for main cause infringement.The tire 2 has excellent endurance quality.

The tire 2 prevents that the core 30 of tyre bead 12 from getting rusty in the case where not damaging leak resistance energy, not only, and reaches raising Endurance quality.According to the present invention, a kind of core 30 for not only preventing tyre bead 12 can be obtained and got rusty, and reach raising endurance quality Tire 2.

As it was previously stated, the protective layer 24 in the tire 2 not only has the air-tightness being mutually equal to inner liner 18, and it is enough Think that the protective layer 24 has the adhesive performance between inner liner 18 and chafer 10.In the tire 2, it is not necessary to such as tradition Tire it is the same, inner liner 18 and aforementioned gap are configured to overlapping to prevent core 30 from getting rusty.And in this configuration, In order to prevent the stripping of inner liner 18 or chafer 10, without setting other portions considered with adhesive performance between the two Part.The protective layer 24 also contributes to the lightweight of tire 2.

As shown in Fig. 2 the second end 66 of the protective layer 24 in the tire 2 leans on axially external than the corner a of core 30.The protection The fully covering of layer 24 is formed at the gap between tire 2 and wheel rim 54.The tire 2 can effectively suppress moisture or oxygen from this Gap is penetrated into tire 2.So as to further prevent that core 30 of the tire 2 etc. from getting rusty.Based on the viewpoint, it is preferable that the guarantor in the tire 2 Sheath 24 is configured to, and its second end 66 leans on axially external than the axially inner side end of the bottom surface 62 of the corner a of core 30, i.e. core 30.

It is same not contain butyl because protective layer 24 contains butyl rubber although the amount of butyl rubber is suitably adapted The rubber components of rubber is compared, and the protective layer 24 has inferior adhesive performance.Therefore, when core is compared at the second end 66 of protective layer 24 30 corner f by it is axially external when, strain can concentrate on second end 66, according to circumstances different, and protective layer 24 may be from anti- Come off on rubber 10 or clinch 8.

As shown in Fig. 2 axially inner side is leaned in the second end 66 of the protective layer 24 in the tire 2 than the corner f of core 30.Therefore, Strain is difficult to the second end 66 for concentrating on the protective layer 24.The tire 2 effectively prevent the protective layer 24 from chafer 10 or Come off on clinch 8.So that the tire 2 has excellent endurance quality.Based on the viewpoint, it is preferable that the protection of the tire 2 Axially inner side is leaned at the axially external end that layer 24 is configured to bottom surface 62 of its second end 66 than the corner f of core 30, i.e. core 30.It is based on Do not damage endurance quality, and the viewpoint got rusty can be adequately suppressed, it is preferable that in the axial direction, protective layer 24 be configured to its Two ends 66 are located between the center of the bottom surface 62 of core 30 and outboard end.

The first end 64 of protective layer 24 in the tire 2 leans on radius side than the axially inner side end of the corner b of core 30, i.e. core 30 Laterally.Not only the second body 24b but also its first noumenon 24a of the protective layer 24 in the tire 2 contribute effectively to resist Leak performance.The tire 2 not only ensures leak resistance energy, and reliably ensure that the bonding plane between protective layer 24 and inner liner 18 Product.The tire 2 does not damage leak resistance energy, can not only prevent that core 30 from getting rusty, and can further improve endurance quality.Base In the viewpoint, it is preferable that the first end 64 of the protective layer 24 of the tire 2 is leaned on the outside of radial direction than the axially inner side end of core 30.Tool For body, it is preferable that the first end 64 of the protective layer 24 is configured to half from the axially inner side end of the core 30 to the first end 64 Footpath direction distance is more than 3mm below 15mm.

As shown in Fig. 1 (or Fig. 2), the part of the end 48 of the inner liner 18 in the tire 2 is towards in radial direction Side is in cusp-shaped.

As it was previously stated, the protective layer 24 in the tire 2 contributes to leak resistance energy.Even if therefore by inner liner 18 and the guarantor Bonding part between sheath 24 is set as the cusp-shaped as the tire 2, and the tire 2 can not only prevent that core 30 from getting rusty, And it is able to maintain that good leak resistance energy.Moreover, by by a part for the end 48 of inner liner 18 towards in radial direction Side is configured to cusp-shaped, during the tire 2 is manufactured, effectively prevents from bringing air in the end 48 into.Moreover, end The inner liner 18 that 48 part is configured to cusp-shaped towards radial direction inner side suppresses the influence to the mass of tire 2.The protection Layer 24 helps to manufacture the lightweight of the tire 2 and tire 2 of high-quality.

A part for the first end 64 of protective layer 24 in the tire 2 is towards radial direction outside in cusp-shaped.Such as preceding institute State, the part of the end 48 of inner liner 18 is towards being in cusp-shaped on the inside of radial direction.Protective layer 24 in the tire 2 with it is interior Bonding part between lining 18, protective layer 24 is in cusp-shaped respectively with inner liner 18.The tire 2 can be by the bonding part pair The quality influence of tire 2 is suppressed to smaller.

It is preferred that, the part of the first end 64 of the protective layer 24 of the tire 2 is from the end 48 of inner liner 18 in radial direction Outside is cusp-shaped, and the first end 64 of the part self-insurance sheath 24 of the end 48 of inner liner 18 is tip on the inside of radial direction Shape.Therefore, preventing from being formed in the part being made up of inner liner 18 and protective layer 24 with especially thick part.In the tire 2 The part being made up of inner liner 18 and protective layer 24 be made up of as entirety much the same thickness.By inner liner 18 and protection The part that layer 24 is constituted contributes to good leak resistance energy as overall.

Double-head arrow T2 in Fig. 2 is the thickness of protective layer 24.Thickness T2 is with the axial direction and in the bottom surface 62 with core 30 Axially inner side end, i.e. the thickness of the protective layer 24 of the corresponding position findings of corner a represents.

It is preferred that, the thickness T2 of the protective layer 24 in the tire 2 is more than 0.4mm below 1.5mm.By the way that the thickness is set For more than 0.4mm, it is reliably suppressed moisture or oxygen and penetrates into protective layer 24 from gap.Protective layer 24 in the tire 2 is effectively prevented Only core 30 gets rusty.By the way that thickness T2 is set as into below 1.5mm, the difference in height band in the second end 66 of the protective layer 24 is prevented Enter air.The protective layer 24 helps to manufacture the tire 2 of high-quality.

Double-head arrow TJ in Fig. 2 is the thickness of the bonding part between protective layer 24 and inner liner 18.Double-head arrow T1 is should The thickness of protective layer 24 (the first noumenon 24a) in bonding part.Thickness TJ and T1 is in the axle with the core 30 on radial direction Axially determined to medial extremity, the i.e. corresponding positions of corner b.

It is preferred that, the thickness T1 of the protective layer 24 in the tire 2 and the thickness TJ of bonding part ratio are more than 50% Less than 90%.By being more than 50% by the ratio set, influence of the inner liner 18 to quality can not only be suppressed, and effectively Ground prevents that the end 48 of inner liner 18 from bringing air into.Based on the viewpoint, it is more than 60% to be more highly preferred to the ratio.By by this compare Rate is set as less than 90%, even in bonding part also result in be made up of the monomer of inner liner 18 part it is roughly the same in Pressure keeps effect.So that the tire 2 maintains good leak resistance energy.Based on the viewpoint, it is 80% to be more highly preferred to the ratio Below.

【Embodiment】

Below, should not be according to the record of the embodiment to the present invention although illustrating the effect of the present invention by embodiment The explanation being defined.

[embodiment 1]

Make the tire shown in Fig. 1-2.The size of the tire is 275/80R22.5.Guarantor is provided with the embodiment 1 Sheath.These are with the column of " Y " protective layer being shown in Table 1 below.The first end of protective layer is configured in the axially inner side than core (the corner b) of core is by the outside of radial direction at end.These are with the column of the position of " out " first end being shown in Table 1 below.The guarantor Second end of sheath is axially disposed and in medial extremity (the corner a) and its outboard end (corner f) of core of core of the bottom surface of core Between.These are with the column of the position at " a-f " second end being shown in Table 1 below.For in the rubber composition of protective layer The ratio (the IIR ratios of table 1) of butyl rubber and matrix material rubber total quality is set to 70 mass %.The thickness of protective layer Degree T2 is 1.0mm.

[comparative example 1]

Removing is not provided with beyond protective layer, and other obtain the tire of comparative example 1 similarly to Example 1.The comparative example 1 is Conventional tire.The situation of protective layer is not provided with to be represented in the protective layer column of table 1 with " N ".

[comparative example 2]

(the corner a) of core is inside by axle for medial extremity of the removing by the position configuration at the second end of protective layer in the bottom surface than core Beyond side, other obtain the tire of comparative example 2 similarly to Example 1.The position at the second end is configured in the bottom surface than core Side is represented in the column of the second end position of table 1 by the situation of axially inner side with " in ".

[comparative example 3]

(the corner f) of core is outside by axle for outboard end of the removing by the position configuration at the second end of protective layer in the bottom surface than core Beyond side, other obtain the tire of comparative example 3 similarly to Example 1.By the position configuration at the second end in the outer of the bottom surface than core Side is represented in the column of the second end position of table 1 by axially external situation with " out ".

[embodiment 2-4]

Remove beyond the thickness T2 of protective layer is set as into table 2 described as follows is the same, other are obtained similarly to Example 1 Embodiment 2-4 tire.

[embodiment 5-7]

Remove by the ratio set of butyl rubber be table 3 described as follows it is the same beyond, other are obtained similarly to Example 1 Embodiment 5-7 tire.

[leak resistance energy]

Tire is assembled on wheel rim, and fills air so that the internal pressure of the tire is regular internal pressure.Put after filling air Put 9 weeks.Internal pressure reduced rate produced by placing is obtained according to the internal pressure after filling and the internal pressure after placement, and according to the reduction Rate evaluates leak resistance energy.The result exponential representation is in following table 1-3.The bigger reduced rate of numerical value is smaller then with excellent Leak resistance energy.

[endurance quality]

Tire is assembled on regular wheel rim, after Jiang Shui (about 100cc) is added in the tire, filled to the tire Air is so that internal pressure is 830kPa.The tire is put into and is set as in 70 DEG C of stove.And place 1 week in this condition, make wheel Tire is deteriorated.By the tire after deterioration be arranged on drum-type running test machine on, and to the tire load standard termination (36.77kN's Longitudinal loading).Make the tire using 80km/h speed in radius to travel on 1.7m wheel hub.Determine the row untill tire destruction Sail distance.Using the result as exponential representation in following table 1-3.The bigger mensuration distance of numerical value is more long then with excellent Endurance quality.

[coming off for chafer]

Trial-production tire is assembled on regular wheel rim, air is filled to the tire so that internal pressure is 830kPa.By the tire The front wheels and rear wheels of truck (10 tons) are installed to, and it is up in ring-like runway with 80km/h speed under maximum load state Sail.Persistently the traveling is untill the treadwear.Tire is reclaimed after traveling, confirms whether chafer comes off.From averagely 100 The number for confirming have chafer to come off is obtained in each trial-production tire, the incidence come off is obtained.It regard the result as index table Show in following table 1-3.Numerical value is more big, and the incidence come off of chafer is lower.

[generation of rust]

Tire is assembled on regular wheel rim, after Jiang Shui (about 100cc) is added in the tire, filled to the tire Air is so that internal pressure is 830kPa.The tire is put into and is set as in 70 DEG C of stove.And place 1 week in this condition, make wheel Tire is deteriorated.Confirm whether the core of the tire bead after deterioration gets rusty.The result is got rusty for " Y ", it is that " N " is represented under not get rusty In the table 1-3 stated.

【Table 1】

The evaluation result of table 1

【Table 2】

The evaluation result of table 2

【Table 3】

The evaluation result of table 3

As shown in table 1-3, the tire of embodiment is had higher rating compared with the tire of comparative example.The result shows the present invention Superiority.

The technology described above for being related to protection of layer is readily adaptable for use in various tires.

Claims (5)

1. a kind of pneumatic tire, it is characterised in that including：

Inner liner, it is used to keep internal pressure；

Chafer, it is placed in the bcad seats of wheel rim；

Clinch, its flange contact with the wheel rim；

Core, it is located on the outside of the radial direction of the chafer；

Protective layer, it is engaged with the end of the inner liner, and is located between the core and the chafer,

The protective layer has：

First end, it is located at the bonding part with the inner liner；With

Second end, it is located on the inside of the radial direction of the core,

The core includes the bottom surface opposed with the bcad seats when the tire is assembled on the wheel rim,

On the tire profile along the plane containing the tire centerline axle, the bottom surface along substantially axial extension,

In the axial direction, second end is located between the medial extremity of the bottom surface and the outboard end of the bottom surface,

The crosslinking rubber that the protective layer is generated by rubber composition is constituted,

The rubber composition includes matrix material rubber,

Described matrix material rubber includes butyl rubber,

The ratio of the butyl rubber and described matrix material rubber total amount is below the mass % of more than 65 mass % 90.

2. pneumatic tire according to claim 1, it is characterised in that

The thickness of the protective layer is more than 0.4mm below 1.5mm.

3. pneumatic tire according to claim 1 or 2, it is characterised in that

The first end is leaned on the outside of radial direction than the axially inner side end of the core.

4. pneumatic tire according to claim 3, it is characterised in that

It is more than 3mm below 15mm from the axially inner side end of the core to the radial direction of first end distance.

5. pneumatic tire according to any one of claim 1 to 4, it is characterised in that

The ratio of the thickness of the protective layer and the thickness of the bonding part is less than more than 50% 90%.