JP2005349889A - Tire-rim-core assembly, method for applying lubricant to pneumatic tire, and method for manufacturing tire-rim-core assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire-rim-core assembly capable of compatibly ensuring the durability in the run-flat traveling and suppressing the vibration in the normal traveling, a method for applying lubricant to a pneumatic tire, and a method for manufacturing the tire-rim-core assembly. <P>SOLUTION: The tire-rim-core assembly 10 comprises a rim 12, a pneumatic tire 14 mounted on the rim 12, and an annular core 16 which is provided on the inner side of the pneumatic tire 14 to support the load applied from the inner circumferential surface side of the tread part 26 during the run-flat traveling. A lubricant unapplied area 34 including at least a tire center area 32 and lubricant applied areas 36A, 36B located so as to hold the lubricant unapplied area 34 from the tire width direction are formed on the inner circumferential surface of the tread part 26. A recessed part 30 is formed on a center part by forming two ring-shaped projecting parts 28 along the tire circumferential direction on the outer circumferential surface side of the core 16, and the lubricant unapplied area 34 is located in the recessed part 30 during the run flat traveling. The vibration of the tire during the traveling can be considerably suppressed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tire / rim / core assembly capable of run-flat running, a method of applying a lubricant to a pneumatic tire, and a method of manufacturing a tire / rim / core assembly.

  A tire / rim / core assembly including a rim, a core assembled to the rim, and a pneumatic tire is useful for run-flat running during emergency running such as puncture. In such a tire / rim / core assembly, there are many examples in which a ring-shaped one is assembled to the rim as a core when viewed from the direction of the tire rotation axis.

When this core is assembled to the rim, during run-flat running, slippage occurs between the core and the inner peripheral surface of the tread due to the difference in diameter between the core and the tire, and heat is generated. As countermeasures, it has been proposed to apply a lubricant to the outer peripheral surface of the core or the inner peripheral surface of the tread. For example, in Patent Document 1, the lubricant is applied to the inner peripheral surface of the tread portion, or the outer periphery of the core is It has been proposed to apply a lubricant to the surface.

Patent Document 2 proposes to devise a component of the lubricant to be applied or to provide a base material impregnated with the lubricant on the inner peripheral surface of the tread or the outer peripheral surface of the core.
JP 2003-326925 A JP 2004-58833 A

  By the way, in order to ensure the durability of the run-flat running, it is necessary to secure the lubricant film thickness to a certain value or more.

  However, when the amount of lubricant applied is large, the lubricant flows and moves in the tire by running with the tire / rim / core assembly attached thereto. As a result, the tire / rim / core assembly is unbalanced, causing vibration. For example, large vibrations are likely to occur when traveling at a high speed of about 120 km / h under normal internal pressure.

  For this reason, there is a limit to the amount of lubricant applied, and there is a problem that it is difficult to ensure the durability of run-flat travel without deteriorating vibration during normal travel.

  In consideration of the above facts, the present invention provides a tire / rim / core assembly that achieves both durability in run-flat running and suppression of vibration in normal running, and a method for applying a lubricant to a pneumatic tire. Another object of the present invention is to provide a method for manufacturing a tire / rim / core assembly.

  The present inventor has paid attention to the fact that when the lubricant is applied to the inner peripheral surface of the tread, the lubricant is conventionally applied to the entire inner peripheral surface of the tread.

  Then, the present inventor has come up with the idea of reducing the amount of application by limiting the application area of the lubricant. Furthermore, the present inventor diligently studied which region of the lubricant is difficult to generate vibration during running, repeated experiments, and completed the present invention.

  The invention according to claim 1 is provided on the inner side of the rim, the pneumatic tire attached to the rim, and the pneumatic tire, and supports a load applied from the inner peripheral surface side of the tread portion during run flat running. In a tire / rim / core assembly having an annular core and lubricant applied to the inner peripheral surface of the tread portion, the region including at least the tire center region of the inner peripheral surface of the tread portion Is a lubricant non-application region.

  The tire center region on the inner peripheral surface of the tread portion refers to a region on the inner peripheral surface of the tread portion where the distance from the tire equator surface is within a predetermined ratio of the distance between the tire equator surface and the tread edge. This predetermined ratio is determined by the tire size, but it is within a range of 10 to 60% regardless of the size.

  Here, the tread end means that a pneumatic tire is mounted on a standard rim prescribed in JATMA YEAR BOOK (2002 edition, Japan Automobile Tire Association Standard), and the maximum load in the applicable size and ply rating in JATMA YEAR BOOK. Fills 100% of the air pressure (maximum air pressure) corresponding to the capacity (internal pressure-load capacity correspondence table) as the internal pressure, and indicates the outermost contact portion in the tire width direction when the maximum load capacity is applied. In addition, when TRA standard and ETRTO standard are applied in a use place or a manufacturing place, it follows each standard.

  Of the lubricant applied to the inner peripheral surface of the tread portion, the lubricant applied to the vicinity of the tire equator has the greatest effect on the tire uniformity. Therefore, by making the tire center region a non-lubricating region as in the invention described in claim 1, vibration of the tire during traveling can be remarkably suppressed, and sufficient durability during run-flat traveling can be achieved. Easy to secure.

  The lubricant is, for example, a polyoxyethylene polyoxypropylene glycol compound, but is not particularly limited.

  According to a second aspect of the present invention, on the outer peripheral surface side of the core, two ring-shaped convex portions are formed along the tire circumferential direction so that a concave portion is formed in the center portion. The lubricant non-application area is located in the recess during traveling.

  This prevents the lubricant non-applied region from coming into contact with the inner peripheral surface of the tread portion during run-flat travel. Therefore, even if the lubricant non-applied region is formed, the lubricant non-applied region and the tread portion It is possible to avoid heat generation between the two.

According to a third aspect of the present invention, the width of the tread portion is Wt, the width of the lubricant non-application region is Wc, and the width of each lubricant application region formed on both sides of the lubricant non-application region in the tire width direction. Is Ws,
0.1 <Wc / Wt <0.3
And 0.2 <Ws / Wt <0.4
It is characterized by satisfying the relationship.

  If Wc / Wt is 0.1 or less or Ws / Wt is 0.4 or more, the amount of lubricant applied cannot be reduced so much. If Wc / Wt is 0.3 or more or Ws / Wt is 0.2 or less, there is a high possibility that the lubricant is not applied in the vicinity of the convex portion of the core.

  According to the third aspect of the present invention, the amount of the lubricant applied can be sufficiently reduced as compared with the conventional case, and the lubricant can be reliably applied in the vicinity of the convex portion of the core.

  The invention according to claim 4 is a method for applying a lubricant to a pneumatic tire in which an annular core that supports a load applied from the inner peripheral surface side of the tread portion during run-flat traveling is provided on the tire inner side. The lubricant is applied to at least a region excluding the tire center region of the inner peripheral surface of the tread portion by causing the lubricant to flow out from the nozzle at a constant flow rate while rotating the pneumatic tire. .

  Thereby, it can apply | coat reliably to the area | region which the inner peripheral surface of a tread part intends with a simple method.

According to a fifth aspect of the present invention, the width of the tread portion is Wt, the width of the lubricant non-application region including at least the tire center region is Wc, and each of the lubricants formed on both sides of the lubricant non-application region in the tire width direction. When the width of the agent application area is Ws,
0.1 <Wc / Wt <0.3
And 0.2 <Ws / Wt <0.4
A lubricant is applied so as to satisfy the above relationship.

  Thereby, the pneumatic tire according to claim 3 can be reliably manufactured by a simple method.

  The invention according to claim 6 applies the lubricant to the pneumatic tire by the method for applying the lubricant to the pneumatic tire according to claim 4, and the tire according to any one of claims 1 to 3. -A rim / core assembly is manufactured.

  Thus, the tire / rim / core assembly according to any one of claims 1 to 3 is manufactured by reliably applying to an intended region of the inner peripheral surface of the tread portion by a simple method. can do.

  Since the present invention is configured as described above, the lubricant can be reliably applied to the intended region of the inner peripheral surface of the tread portion by a simple method, and durability in run-flat traveling can be ensured. A tire / rim / core assembly that achieves both vibration suppression during traveling can be manufactured by a simple method.

  Hereinafter, embodiments will be described and embodiments of the present invention will be described. As shown in FIG. 1, a tire / rim / core assembly 10 according to an embodiment of the present invention is provided inside a rim 12, a pneumatic tire 14 attached to the rim 12, and a pneumatic tire 14. Core 16 formed.

  The pneumatic tire 14 includes a belt 24 and a tread portion 26 having a groove on the outer peripheral surface side outside the crown portion of the carcass 22 extending in a toroidal shape.

  The core 16 is formed into an annular shape and assembled to the rim 12 so as to support a load applied from the inner peripheral surface side of the tread portion 26 during run-flat traveling. On the outer peripheral surface side of the core 16, a concave portion 30 is formed in the center portion by forming two ring-shaped convex portions 28 along the tire circumferential direction. The non-application area 34 is positioned in the recess 30.

  A ring-shaped lubricant non-application region 34 including at least the tire center region 32 is formed on the inner peripheral surface of the tread portion 26 of the pneumatic tire 14, and both sides of the lubricant non-application region 34 in the tire width direction are formed. Are formed with ring-shaped lubricant coating layers 40A and 40B. Therefore, the inner peripheral surface of the tread portion 26 includes a ring-shaped lubricant non-application region 34 and lubricant application regions 36A and 36B on both sides in the tire width direction so as to sandwich the lubricant non-application region 34. Is done.

In the present embodiment, the lubricant application areas 36A and 36B have the same width. Further, when the width of the tread portion 26 is Wt, the width of the lubricant non-application area 34 is Wc, and the width of the lubricant application areas 36A and 36B is Ws,
0.1 <Wc / Wt <0.3
And 0.2 <Ws / Wt <0.4
Meet the relationship.

  If Wc / Wt is 0.1 or less or Ws / Wt is 0.4 or more, the amount of lubricant applied cannot be reduced so much. If Wc / Wt is 0.3 or more, or Ws / Wt is 0.2 or less, there is a high possibility that the lubricant is not applied in the vicinity of the convex portion 28 of the core 16, which is not preferable. Absent.

  Hereinafter, a method of applying a lubricant to the inner peripheral surface side of the tread portion 26 of the pneumatic tire 14 will be described.

  In the present embodiment, a pneumatic tire 44 for a general passenger car in which a lubricant is not applied to the inner peripheral surface side of the tread portion is rotated, and a nozzle 46 that flows out the lubricant is used as a lubricant on the inner peripheral surface of the tread portion 26. Close to the application areas 36A and 36B (see FIG. 2), the lubricant flows out from the nozzle 46 at a constant flow rate. The preferable rotation speed of the pneumatic tire 44 is in the range of 2 to 10 rpm, and the preferable flow rate of the lubricant from the nozzle 46 is in the range of 100 to 600 cc / min.

  Thus, the lubricant coating layers 40A and 40B are formed by allowing the lubricant to flow out of the nozzle 46. When the lubricant is applied, the lubricant application layers 40A and 40B are applied so that the widths of the lubricant application layers 40A and 40B are equal to the above Ws, and the lubricant non-application region 34 formed between the lubricant application layers 40A and 40B. The width of the coating is applied so as to be the above Wc. The tip of the nozzle 46 is divided into two, and the lengths in the tire width direction of the nozzle tips 48A and 48B are adjusted to the widths of the lubricant application regions 36A and 36B, respectively, and the nozzle tips 48A and 48B In order to shorten the time required for application, it is preferable that the separation interval L in the tire width direction is matched to the width of the lubricant non-application region 34.

  After manufacturing the pneumatic tire 14 (see FIG. 1) in which the lubricant coating layers 40A and 40B are formed on the pneumatic tire 44 in this way, the rim 12 on which the core 16 is assembled is incorporated into the pneumatic tire 14. Thus, the tire / rim / core assembly 10 is manufactured.

  As described above, in the present embodiment, the region including at least the tire center region on the inner peripheral surface of the tread portion 26 is defined as the lubricant non-application region 34. Here, among the lubricants applied to the inner peripheral surface of the tread portion 26, the lubricant applied to the vicinity of the tire equator has a great influence on the tire uniformity. Therefore, by setting the tire center area as the lubricant non-application area 34, vibration of the tire during traveling can be remarkably suppressed. Moreover, it is easy to ensure sufficient durability in run-flat running.

  Further, a recess 30 is formed in the center portion on the outer peripheral surface side of the core 16, and the lubricant non-application region 34 is located in the recess 30 during the run-flat running, so the lubricant non-application region 34 is formed. Even so, it is avoided that the lubricant non-application area 34 and the tread portion 26 are rubbed and generate heat during the run-flat running.

  Furthermore, since the values of Wc / Wt and Ws / Wt satisfy the above conditions, the amount of lubricant applied can be sufficiently reduced as compared with the conventional case, and the convex portion 28 of the core 16 can be reduced. The lubricant can be reliably applied in the vicinity.

  Further, when the lubricant application layers 40A and 40B are formed, the lubricant is applied by causing the lubricant to flow out from the nozzle 46 at a constant flow rate while rotating the pneumatic tire 44, so that the inner circumference of the tread portion 26 is It can apply | coat reliably to the area | region which the surface intends by a simple method.

<Experimental example>
(Conventional tire / rim / core assembly)
The inventor first conducted the following experiment using the conventional tire / rim / core assembly. The tire / rim / core assembly of this conventional example is a pneumatic tire having a lubricant application layer formed by applying a lubricant over the entire inner peripheral surface of the tread portion, and a rim having a core assembled therein is incorporated. It is a thing. The thickness of the lubricant coating layer is 0.6 mm, and the width of the lubricant coating layer is 150 mm.

In this experiment, the tire / rim / core assembly of this conventional example is attached to the right rear wheel of the test vehicle, the internal pressure of the pneumatic tire is set to 0 kgf / m ² , and run flat running at a constant speed of 90 km / h. The travel distance until the side wall was cracked was measured. An FR vehicle with a displacement of 2500 cc was used as a test vehicle.

  The measured travel distance is shown in Table 1 as the durable travel distance in run-flat travel.

  In addition, the inventor measured the unbalance of the conventional tire / rim / core assembly and assigned an index of 100. This is also shown in Table 1.

(Tire / Rim / Core Assembly of Example)
Further, the present inventor sets the thicknesses of the lubricant coating layers 40A and 40B to 0.6 mm for the pneumatic tire 14 of the above embodiment, and sets the width Ws of the lubricant coating regions 36A and 36B to 50 mm for both. Then, a lubricant non-application region 34 having a width Wc of 50 mm was manufactured. Further, the core 16 was assembled to the pneumatic tire 14, and then a rim was assembled.

The tire / rim / core assembly 10 of this embodiment is attached to the right rear wheel of the test vehicle in the same manner as the tire / rim / core assembly of the conventional example, and the internal pressure of the pneumatic tire 14 is set to 0 kgf / The vehicle was run in a flat state at a constant speed of 90 km / h under the condition of m ² , and the travel distance until the side wall was cracked was measured. As the test vehicle, the same vehicle used in the conventional tire / rim / core assembly was used.

  The measured travel distance is shown in Table 1 above. As can be seen from Table 1, the durability travel distance in the run-flat travel was 10 km longer than that of the conventional tire / rim / core assembly.

  Further, the inventor measured the unbalance of the tire / rim / core assembly 10 of the example, and performed a relative evaluation with respect to the tire / rim / core assembly of the conventional example. The evaluation results are also shown in Table 1. In Table 1, the smaller the index, the better the balance.

  As can be seen from Table 1, the unbalance of the tire / rim / core assembly 10 of the embodiment was significantly improved compared to the tire / rim / core assembly of the conventional example.

(Comparative tire / rim / core assembly)
Further, the present inventor applied the lubricant over the entire inner peripheral surface of the tread portion in the conventional tire / rim / core assembly, and also increased the thickness of the lubricant application layer formed by applying the lubricant. A reduced tire / rim / core assembly of a comparative example was manufactured. That is, the layer thickness of the lubricant coating layer was set to 0.4 mm. The width of the lubricant coating layer is 150 mm as in the conventional tire / rim / core assembly.

The tire / rim / core assembly of this comparative example is attached to the right rear wheel of the test vehicle in the same manner as the tire / rim / core assembly of the conventional example, and the internal pressure of the pneumatic tire is set to 0 kgf / m ^2. In this state, the vehicle was run flat at a constant speed of 90 km / h, and the travel distance until the side wall was cracked was measured. As the test vehicle, the same vehicle used in the conventional tire / rim / core assembly was used.

  Further, the inventor measured the unbalance of the tire / rim / core assembly of this comparative example, and performed a relative evaluation with respect to the tire / rim / core assembly of the conventional example.

  The measured traveling distance and the evaluation result of the unbalance property are shown in Table 1 above. As can be seen from Table 1, the imbalance of the tire / rim / core assembly of the comparative example was significantly improved compared to the tire / rim / core assembly of the conventional example. The durable mileage was 78 km shorter than the conventional tire / rim / core assembly.

  The embodiments of the present invention have been described with reference to the embodiments. However, the above embodiments are merely examples, and various modifications can be made without departing from the scope of the invention. Needless to say, the scope of rights of the present invention is not limited to the above embodiment.

1 is a tire radial direction cross-sectional view of a tire / rim / core assembly according to an embodiment of the present invention. 1 is a perspective view showing that a lubricant coating layer is formed on a pneumatic tire constituting a tire / rim / core assembly according to an embodiment of the present invention.

Explanation of symbols

10 tire / rim / core assembly 12 rim 14 pneumatic tire 16 core 26 tread portion 28 convex portion 30 concave portion 32 tire center region 34 lubricant non-application region 36A, B lubricant application region 44 pneumatic tire

Claims (6)

A rim, a pneumatic tire attached to the rim, and an annular core that is provided inside the pneumatic tire and supports a load applied from the inner peripheral surface side of the tread portion during run flat running. In the tire / rim / core assembly in which the lubricant is applied to the inner peripheral surface of the tread portion,
A tire / rim / core assembly in which at least a region including the tire center region in the inner peripheral surface of the tread portion is a lubricant non-application region.   On the outer peripheral surface side of the core, a concave portion is formed in the center portion by forming two ring-shaped convex portions along the tire circumferential direction, and the lubricant non-application region is formed during run flat running. The tire / rim / core assembly according to claim 1, wherein the tire / rim / core assembly is located in the recess. When the width of the tread portion is Wt, the width of the lubricant non-application region is Wc, and the width of each lubricant application region formed on both sides in the tire width direction of the lubricant non-application region is Ws,
0.1 <Wc / Wt <0.3
And 0.2 <Ws / Wt <0.4
The tire / rim / core assembly according to claim 2, wherein the relationship is satisfied. A method of applying a lubricant to a pneumatic tire in which an annular core that supports a load applied from the inner peripheral surface side of the tread portion during run flat traveling is provided on the tire inner side,
The lubricant is applied to at least a region excluding the tire center region of the inner peripheral surface of the tread portion by causing the lubricant to flow out from the nozzle at a constant flow rate while rotating the pneumatic tire. Applying lubricant to pneumatic tires. When the width of the tread portion is Wt, the width of at least the lubricant non-application region including the tire center region is Wc, and the width of each lubricant application region formed on both sides in the tire width direction of the lubricant non-application region is Ws. ,
0.1 <Wc / Wt <0.3
And 0.2 <Ws / Wt <0.4
The method of applying a lubricant to a pneumatic tire according to claim 4, wherein the lubricant is applied so as to satisfy the relationship.   The tire / rim / core assembly according to claim 1 is manufactured by applying a lubricant to the pneumatic tire by the method of applying a lubricant to the pneumatic tire according to claim 4. A method for manufacturing a tire / rim / core assembly.

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