JP2011020479A - Pneumatic tire with sound controlling body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a sound controlling body to be bonded firmly without providing buff treatment on a tread inner surface and to make the body exercise a blowout sealing effect. <P>SOLUTION: The sound controlling body 9 made of a sponge material is glued to the tread inner surface 2S using a viscous sealing agent J. The sound controlling body 9 includes a sealing agent permeated layer 10 of the sponge material into which the viscous sealing agent J is permeated and a sound controlling layer 11 into which the viscous sealing agent J is not permeated. A sealing layer 12 made of the viscous sealing agent J is formed between the sealing agent permeated layer 10 and the tread inner surface 2S. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a pneumatic tire with a sound damper that suppresses cavity resonance by a sound damper made of a sponge material adhered to the inner surface of a tread.

  In recent years, by attaching a long band-shaped sound absorber made of sponge material along the tire circumferential direction to the inner surface of the tread of a pneumatic tire, technology to suppress cavity resonance in the tire lumen and reduce road noise Has been proposed. As a method for attaching the sound absorber, it has been proposed to use, for example, a synthetic rubber adhesive in which chloroprene rubber or the like is dissolved in an organic solvent, and an adhesive such as a double-sided tape.

  However, a release agent is generally applied to the tire cavity surface after vulcanization molding in order to improve the releasability from the vulcanization bladder. In addition, a plurality of exhaust grooves for venting air are formed on the surface of the bladder to prevent air accumulation with the tire lumen surface during vulcanization molding. The reverse trace of the exhaust groove remains as an uneven pattern on the surface.

  Therefore, it is not sufficient to use the adhesive material in order to firmly bond the sound-damping body to the inner surface of the tread. For example, the inner surface of the tread is buffed to remove the release agent and the uneven pattern. It is desired to increase the adhesion area by flattening (see Patent Documents 1 and 2).

International Publication No. WO2003 / 103989 Pamphlet JP 2003-063208 A

  However, since the buff processing requires labor and labor, the work efficiency is lowered. Also, depending on the buffing condition, the release agent is not sufficiently removed and the adhesive strength is impaired, or the thickness of the inner liner rubber layer forming the tire lumen surface is excessively reduced, thereby impairing the air tightness of the tire. Various problems occur.

  Therefore, the present invention uses a viscous sealant suitable as a puncture seal as an adhesive, a sealant permeation layer in which the viscous sealant has penetrated into the sponge material, and a viscous sealant. And a buffing treatment on the inner surface of the tread, based on the formation of a sealing layer made of a viscous sealing agent between the sealing agent infiltration layer and the inner surface of the tread. Without applying, the sound damping body can be firmly adhered to the inner surface of the tread, the above-mentioned problems caused by buffing can be solved, and the sealing effect at the time of puncture, for example, can be exhibited by the sealing layer and the sealing agent permeation layer. An object of the present invention is to provide a pneumatic tire with a sound control body capable of improving the safety of traveling.

In order to solve the above-mentioned problem, the invention of claim 1 of the present application comprises a pneumatic tire and a sound damper made of a sponge material having an outer peripheral surface bonded to the inner surface of the tread of the pneumatic tire and extending in the tire circumferential direction. A pneumatic tire with a noise control body,
The sound control body is adhered to the inner surface of the tread using a viscous sealant,
The sound damper is composed of a sealing agent permeation layer on the outer peripheral surface side through which the viscous sealant has penetrated into the sponge material, and a sound control layer on the inner peripheral surface side through which the viscous sealant has not penetrated. Become
In addition, a seal layer made of the viscous sealant is formed between the sealant permeation layer and the inner surface of the tread.

  Further, in the invention of claim 2, the sealant permeation layer has a thickness T2 of 1 to 10 mm, and is a sum (T1 + T2) of the sealant permeation layer thickness T2 and the seal layer thickness T1. The thickness of the agent is 3 to 10 mm, and the thickness T3 of the sound control layer is 5 to 40 mm.

  In the invention according to claim 3, the sound damping body is characterized in that a width Wa in a tire axial direction is 80 to 120% of a tread ground contact width TW.

  In the invention of claim 4, the viscous sealing agent is characterized by containing 30 to 50 parts by mass of polybutene with respect to 100 parts by mass of the viscous sealing agent.

  The tread ground contact width means the maximum width in the tire axial direction of the ground contact surface that comes into contact when a normal load is applied to a tire that is assembled with a normal rim and filled with a normal internal pressure. The “regular rim” is a rim determined for each tire in the standard system including the standard on which the tire is based, for example, a standard rim for JATMA, “Design Rim” for TRA, or ETRTO means "Measuring Rim". The “regular internal pressure” is the air pressure defined by the standard for each tire. If JATMA, the maximum air pressure is specified. If TRA, the maximum value described in the table “TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES”, ETRTO Means "INFLATION PRESSURE", but in the case of passenger car tires, it is 180 kPa. The “regular load” is a load determined by the standard for each tire. The maximum load capacity in the case of JATMA, the maximum value described in the table “TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES” in the case of TRA, If it is ETRTO, it is "LOAD CAPACITY".

  In the present invention, the sound absorber is adhered to the inner surface of the tread using a viscous sealant suitable for puncture sealing. At this time, on the sound damping body, a sealing agent permeation layer in which the viscous sealing agent has penetrated into the sponge material, and a sound damping layer in which the viscous sealing agent has not penetrated, and the sealing agent penetration layer, A seal layer made of a viscous sealant is formed between the inner surface of the tread.

  Since the viscous sealing agent is excellent in adhesiveness, the sealing layer can ensure the adhesive strength with the inner surface of the tread without performing buffing or the like. Further, the sealing agent permeation layer can enhance the bonding force between the sound absorber and the seal layer. Therefore, the sound absorber can be firmly bonded to the inner surface of the tread by the interaction between the seal layer and the sealant permeation layer. In addition, the sound damping body can exhibit an original sound damping effect due to the sound-damping layer into which the viscous sealant has not penetrated, and can suppress road resonance within the tire lumen and reduce road noise.

  In the present invention, the viscous sealing agent is stored by the sealing layer and the sealing agent permeation layer. Therefore, at the time of occurrence of puncture, the puncture hole can be sealed by the stored viscous sealant, and the puncture sealing function can be exhibited.

It is sectional drawing which shows one Example of the pneumatic tire with a noise suppression body of this invention. It is the circumferential direction sectional view along the tire equator. It is a partial expanded sectional view which expands and shows the adhesion part of a beltlike sheet. It is sectional drawing which shows the other cross-sectional shape of a noise suppression body. It is sectional drawing which shows an example of the sticking apparatus of a damping body.

Hereinafter, embodiments of the present invention will be described in detail.
In FIG. 1, a pneumatic tire 1 with a sound control body according to the present embodiment includes a pneumatic tire 1 </ b> A, and a sponge material that extends in the tire circumferential direction with an outer peripheral surface bonded to a tread inner surface 2 </ b> S of the pneumatic tire 1 </ b> A. And a sound body 9.

  The pneumatic tire 1 </ b> A is a tubeless tire, and includes a tread portion 2, a pair of sidewall portions 3 extending inward in the tire radial direction from both ends thereof, and a bead positioned at an inner end of each sidewall portion 3. The tire lumen surface is covered with an inner liner rubber (not shown) made of a low air permeability rubber. Various tires can be applied as the pneumatic tire 1A without being restricted by its internal structure or category. However, passenger car tires that are strongly required to be quiet in the passenger compartment, particularly radial tires for passenger cars having a flatness ratio of 60% or less are preferably employed.

  The pneumatic tire 1A is reinforced by a tire cord layer including a carcass 6 straddling between the bead portions 4 and 4 and a belt layer 7 disposed radially outside the carcass 6 and inside the tread portion 2. . The carcass 6 is formed of one or more, for example, one carcass ply in which organic fiber cords are arranged at an angle of, for example, 70 to 90 ° with respect to the tire circumferential direction. Both ends of the carcass ply are folded around the bead core 5. The belt layer 7 is formed of a plurality of, for example, two belt plies in which steel cords are arranged at an angle of, for example, 10 to 40 ° with respect to the tire circumferential direction. The belt layer 7 has a belt rigidity increased by crossing the steel cords between the plies, and reinforces the tread portion 2 with a tagging effect.

  Next, the sound damper 9 is made of a strip-like sponge material that is long in the tire circumferential direction, and is adhered to the tread inner surface 2S along the tire equator C in the tire circumferential direction.

  In this example, as shown in FIG. 2, the one end e1 and the other end e2 in the circumferential direction of the sound damping body 9 are abutted with each other, that is, the sound damping body 9 is continuously formed in an annular shape. Is illustrated. However, the one end part e1 and the other end part e2 may be separated in the circumferential direction. In such a case, the separation part is used to suppress the influence on the weight balance and prevent the tire uniformity from being lowered. The circumferential length is preferably 100 mm or less, more preferably 80 mm or less.

  The sponge material is a sponge-like porous structure, for example, a web in which animal fibers, plant fibers, or synthetic fibers are entangled and integrally connected in addition to a so-called sponge having open cells in which rubber or synthetic resin is foamed. Including the shape. In this example, the sound control body 9 is an open-cell sponge material made of polyurethane. The sponge material as described above has a porous portion on the surface and / or inside that converts vibration energy of air into heat energy and consumes it, thereby reducing cavity resonance energy in the tire lumen and reducing road noise. Can be controlled. Further, since the sponge material is easily deformed such as contraction and bending, the influence on the tire deformation during traveling is small, and it is possible to prevent the steering stability from deteriorating.

  As the sponge material, it is preferable to use one having a specific gravity of 0.005 to 0.060. When the sponge material is out of this range, the effect of suppressing the cavity resonance energy in terms of the pore ratio and the like is lowered. A sponge having a hardness of 80 to 150 N and a tensile strength of 120 to 160 kPa is preferred. When the sponge hardness is limited, the sound damping body 9 is ensured to have an appropriate elongation. This elongation serves to widely disperse the stress when strain is applied to the sound damper 9. Particularly preferably, the sponge hardness is 90 N or more, and the upper limit is preferably 130 N or less, more preferably 110 N or less. Further, when the tensile strength of the sponge material is limited, the strength against the stress can be further increased. Particularly preferably, the tensile strength of the sponge material is 130 kPa or more, and the upper limit thereof is not particularly limited, but is preferably 150 kPa or less in view of cost, productivity, market availability and the like.

  The sponge hardness was measured in accordance with Method A (Section 6.3) of the “Hardness” measurement method defined in Section 6 of “Soft urethane foam test method” of JIS K6400. Value. Further, the tensile strength of the sponge is a value measured with respect to a No. 1 type dumbbell-shaped test piece in accordance with “tensile strength and elongation” of item 10 of the same JIS.

  Sponge materials include ether type polyurethane sponge, ester type polyurethane sponge, synthetic resin sponge such as polyethylene sponge, chloroprene rubber sponge (CR sponge), ethylene propylene rubber sponge (EPDM sponge), nitrile rubber sponge (NBR sponge), etc. A rubber sponge can be suitably used, and a polyurethane-based sponge including an ether-based polyurethane sponge is particularly preferable from the viewpoints of sound damping properties, light weight, foam controllability or durability.

  Next, the sound damper 9 is adhered to the tread inner surface 2S by using the viscous sealant J.

  Here, as the viscous sealing agent J, various sealing agents having viscosity can be used. For example, those exhibiting a substantially liquid state at normal temperature (20 ° C.) can be preferably employed. In particular, in a temperature range of −20 to 60 ° C., a sealant that can enter a nail hole and seal the nail hole and prevent leakage of tire internal pressure can be suitably used.

  As such a viscous sealing agent J, what contains 30-50 mass parts of polybutenes with respect to 100 mass parts of viscous sealing agents is preferable. As is well known, polybutene is a viscous liquid polymer obtained by cationic polymerization of isobutene and normal butene, and has excellent adhesiveness, and the adhesiveness and viscosity do not change even after long-term use. It does not solidify and dry. Further, since there is almost no deterioration in quality even with heating and pressurization, and the consistency and tackiness can be stably maintained from the initial use to the final use of the tire, it can be particularly preferably employed.

  The viscous sealant J is desirably blended with unvulcanized butyl rubber in the polybutene in order to further improve the adhesiveness and sealing performance. The blending ratio of butyl rubber and polybutene is preferably in the range of 40:60 to 60:40. For adjusting the viscosity and workability, for example, a white filler or zinc oxide may be added.

  And the outer peripheral surface So of the noise suppression body 9 is adhere | attached on the tread inner surface 2S using such viscous sealing agent J. At this time, as shown in FIG. 3, the sound damper 9 includes the sealing agent permeation layer 10 on the outer peripheral surface So side in which the viscous sealing agent J has penetrated into the sponge material, and the viscous sealing agent J. A sound-insulating layer 11 on the inner peripheral surface Si side that has not penetrated is formed, and a seal layer 12 made of the viscous sealant J is formed between the sealant-penetrated layer 10 and the tread inner surface 2S. It is formed.

  Here, since the viscous sealing agent J is excellent in adhesiveness, the adhesive strength between the tread inner surface 2S can be ensured by the sealing layer 12 without performing buffing or the like. Further, since the sealing agent permeation layer 10 can enhance the bonding force between the sound damping body 9 and the sealing layer 12, the sound damping body 9 is brought into contact with the inner surface 2S of the tread by the interaction between the sealing layer 12 and the sealing agent permeation layer 10. It can be firmly bonded to. Further, in the sound damping body 9, since the sound damping layer 11 into which the viscous sealant J has not penetrated is made of only a sponge material, the original sound damping effect can be exhibited, and cavity resonance within the tire lumen can be achieved. It can be suppressed and road noise can be reduced.

  In this embodiment, the viscous sealant J is stored in the seal layer 12 and the sealant permeation layer 10. Therefore, when the puncture occurs, the stored viscous sealant J can seal the puncture hole, and can also exhibit a puncture seal function.

  At this time, the thickness T2 of the sealing agent permeation layer 10 is preferably 1 to 10 mm, and the sum of the thickness T2 of the sealing agent permeation layer 10 and the thickness T1 of the sealing layer 12 (T1 + T2). The total seal thickness (T1 + T2) is preferably 3 to 10 mm. Further, the thickness T3 of the sound damping layer 11 is preferably 5 to 40 mm.

  When the thickness T2 of the sealing agent permeation layer 10 is less than 1 mm, the coupling force between the sound damper 9 and the seal layer 12 becomes insufficient, peeling occurs at this portion, and the durability of the noise damper 9 is improved. Reduce. Even if the thickness T2 exceeds 10 mm, no further increase in the bonding force can be expected, leading to an unnecessary increase in cost and mass. From such a viewpoint, the lower limit value of the thickness T2 is preferably 1.0 mm or more, and the upper limit is preferably 10.0 mm or less.

  If the total seal thickness (T1 + T2) is less than 3 mm, the amount of the viscous sealant J stored is insufficient, making it difficult to perform the puncture seal function. Can not be expected to increase further, leading to an unnecessary increase in cost and mass. From such a viewpoint, the lower limit value of the total seal thickness (T1 + T2) is preferably 3.0 mm or more, and the upper limit is preferably 10.0 mm or less.

  On the other hand, if the thickness T3 of the sound-suppressing layer 11 is less than 5 mm, the sound-suppressing effect is not sufficiently exhibited, and it becomes difficult to reduce road noise. On the other hand, even if it exceeds 40 mm, further increase in the sound damping effect cannot be expected, leading to an unnecessary increase in cost and mass. From such a viewpoint, the lower limit value of the thickness T3 of the sound damping layer 11 is preferably 5.0 mm or more, and the upper limit is preferably 40.0 mm or less.

  When the thickness varies, the thicknesses T1, T2, and T3 are obtained as average values of the maximum value and the minimum value, respectively.

  Further, the width Wa (shown in FIG. 1) of the sound damper 9 in the tire axial direction is preferably in the range of 80 to 120% of the tread ground contact width TW, and if less than 80%, the tire puncture is sufficiently covered. On the contrary, even if it exceeds 120%, a further increase in the puncture seal cannot be expected, leading to an unnecessary increase in cost and mass. From such a viewpoint, the lower limit of the width Wa is more preferably 90% or more of the tread ground contact width TW, and the upper limit is more preferably 110% or less.

  In this example, a rectangular shape is illustrated as a cross-sectional shape perpendicular to the length direction of the sound damper 9, but various shapes such as a trapezoidal shape, a triangular shape, and a semicircular shape can be adopted. . However, as shown in FIG. 4, by providing one or more circumferential grooves 20 on the inner peripheral surface Si side of the sound damper 9, mountain-shaped raised portions 21 are formed on both sides of the circumferential grooves 20. Those are preferred. Such a sound damping body 9 can increase the surface area due to the unevenness caused by the circumferential groove 20 and the raised portion 21, and thus can exhibit a higher sound damping effect. Further, the increase in the surface area also improves the heat dissipation of the sound control body 9 and is useful for preventing its own thermal destruction and the like. In this case, the sealing agent permeation layer 10 is formed on the outer peripheral surface So side with respect to the groove bottom of the circumferential groove 20, that is, the height h from the outer peripheral surface So of the groove bottom is set to the thickness of the sealing agent permeation layer 10. It is preferable to set it to be larger than the length T2 (h> T2) from the viewpoints of sound damping properties and puncture sealing properties.

  Next, an example of a method for attaching such a sound damper 9 will be described using the device 29 in FIG. In this example, the sound-damping body 9 is rewound and supplied to the tread inner surface 2S from the sound-damping body holder 30 that winds and holds the sound-damping body 9 in a roll shape. At that time, the viscous sealing agent J is applied to the outer peripheral surface So of the rewound sound control body 9 with a predetermined thickness using, for example, the application roller 31. Reference numeral 32 denotes a supply container for the viscous sealant J. Then, the sound control body 9 to which the viscous sealant J is applied is pasted while being pressed against the inner surface 2S of the tread using the pressing roller 33. At this time, a part of the applied viscous sealant J is infiltrated into the sponge material of the sound control body 9 by the pressing to form the sealant infiltration layer 10 and the applied viscous seal. The remainder of the agent J remains as the seal layer 12 between the seal agent permeation layer 10 and the inner surface of the tread. At this time, the thicknesses T <b> 1 and T <b> 2 can be adjusted by the application thickness of the viscous sealant J to the sound damper 9 and the pressing force by the pressing roller 33.

  In addition, as another method of attaching the sound damper 9, the viscous sealant J is applied to the inner surface 2S of the tread with a predetermined thickness, and the sound absorber 9 is applied on the applied viscous sealant J. Paste while pressing. Even in such a case, the thicknesses T1 and T2 can be adjusted by the application thickness of the viscous sealant J to the inner surface 2S of the tread and the pressing force of the noise control body 9.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to embodiment of illustration, It can deform | transform and implement in a various aspect.

In order to confirm the effect of the present invention, a pneumatic tire with a sound control body (tire size: 215 / 60R16) was prototyped with the specifications shown in Table 1 using the apparatus shown in FIG. The test was conducted for sound performance, anti-peeling resistance (durability) of the sound control body, and puncture seal performance. The composition of the viscous sealant used is shown in Table 2.

Specifications of sound control materials, etc. Material: Ether polyurethane sponge ("E16" manufactured by Maruzuru)
Specific gravity: 0.016
Cross-sectional shape: Horizontally long rectangular shape with a width of 150 mm and a thickness of 10 mm (tread grounding width TW = 150 mm

(1) Sound control:
A pneumatic tire with a noise control body is mounted on all wheels of a vehicle (domestic 2400cc, FF car) under the conditions of a rim (16 × 7J) and internal pressure (200kPa), and a road noise measurement path (asphalt rough road) The vehicle interior noise when traveling at a speed of 60 km / h was collected with a microphone installed at the driver's seat window side ear position, and the sound pressure level of the peak value of the air column resonance sound around 230 Hz was measured. Then, using the comparative example 1 as a reference, the sound pressure level is displayed as a decrease value. -(Minus) display means that road noise is reduced.

(2) Peeling resistance (durability) of the sound control body:
Pneumatic tire with noise control body running on drum (1.7m diameter) under conditions of rim (16 × 7J), internal pressure (200kPa), longitudinal load (1.2 times the maximum value specified by JATMA) The vehicle was run at 12000 km at a speed of 80 km / h, and the presence or absence of peeling of the noise control body after running was checked.
Peeled ---- X,
No peeling --- ○
As evaluated.

(3) Punk seal performance:
A nail with a diameter of 3 mm was pierced into the tread of a pneumatic tire with a sound control body assembled with a rim under the conditions of a rim (16 × 7 J) and internal pressure (200 kPa), then pulled out, and then on the drum (1.7 m in diameter) Then, the internal pressure after traveling 200 km at a longitudinal load (1.2 times the maximum value specified by JATMA) and a traveling speed of 80 km / h was measured.
When the internal pressure after traveling is 85% or more of the internal pressure before traveling ---
When the internal pressure after traveling is less than 85% of the internal pressure before traveling --- ×
As evaluated.

  The pneumatic tire with a sound control body of the embodiment can firmly adhere the sound control body to the inner surface of the tread without performing buffing etc. on the inner surface of the tread, and can also exhibit a sealing effect at the time of puncture, so that traveling safety is achieved. Can be confirmed.

DESCRIPTION OF SYMBOLS 1 Pneumatic tire with a sound control body 1A Pneumatic tire 2S Tread inner surface 9 Sound control body 10 Sealing agent penetration layer 11 Sound control layer 12 Sealing layer J Viscous sealant So Outer peripheral surface

Claims (4)

A pneumatic tire with a sound control body comprising a pneumatic tire and a sound control body made of a sponge material whose outer peripheral surface is bonded to the inner surface of the tread of the pneumatic tire and extends in the tire circumferential direction,
The sound control body is adhered to the inner surface of the tread using a viscous sealant,
The sound damper is composed of a sealing agent permeation layer on the outer peripheral surface side through which the viscous sealant has penetrated into the sponge material, and a sound control layer on the inner peripheral surface side through which the viscous sealant has not penetrated. Become
In addition, a pneumatic tire with a sound damper, wherein a sealing layer made of the viscous sealing agent is formed between the sealing agent permeation layer and the inner surface of the tread.   The thickness T2 of the sealing agent permeation layer is 1 to 10 mm, and the total sealing thickness that is the sum (T1 + T2) of the thickness T2 of the sealing agent permeation layer and the thickness T1 of the sealing layer is 3 to 10 mm. And the thickness T3 of the said sound control layer is 5-40 mm, The pneumatic tire with a sound control body of Claim 1 characterized by the above-mentioned.   The pneumatic tire with a sound absorber according to claim 1 or 2, wherein a width Wa in the tire axial direction of the sound absorber is 80 to 120% of a tread ground contact width TW.   The said viscous sealing agent contains 30-50 mass parts of polybutene with respect to 100 mass parts of viscous sealing agents, The pneumatic with a sound control body in any one of Claims 1-3 characterized by the above-mentioned. tire.

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