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🚗 | [Lexus NX new model] Yokohama tire BluEarth-XT AE61 installed on new car

Photo Lexus NX new model (NX450h +)

[Lexus NX new model] Yokohama tire BluEarth-XT AE61 installed on new cars

If you write the contents roughly
In addition to achieving a softer ride quality than run-flat tires that have adopted conventional standards, the weight reduction of the tires has also improved fuel efficiency.

Yokohama Rubber Co., Ltd. is the first Lexus PHEV, "NX", as a tire for new vehicle installation (OE), "BluEart ... → Continue reading


Wikipedia related words

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Fuel efficiency

Run flat tires

Run flat tires (English: Run flat tire) IsPunkIt is designed to be able to travel about 100 km even afterタ イ ヤ.. Part ofPassenger carandNew transportation system OfRailway carIt is adopted in.Also,Military vehicleInFour-wheel drive vehicle,Six-wheel drive truckTransport vehicles such asWheeled armored car,Wheeled tankWheeled typeArmored combat vehicleSo in many casesCombat tires Run-flat tires called (combat tires) are installed.


With ordinary tires, the maneuvering performance deteriorates sharply immediately after a flat tire, and the driver cannot control the car, which may lead to an accident.Even if the vehicle can be stopped, it will be an unpredictable sudden stop for the following vehicle, and there is a possibility of being hit by the following vehicle.With run-flat tires, you can continue to drive for a while after a flat tire, avoiding the risk of encountering an accident.[1]..Especially on busy roadshighwayIn addition, it is possible to avoid tire replacement and puncture repair by stopping the vehicle in dangerous conditions and places such as insecure areas in other countries and military vehicles in battle or in NBC environment.[2][3].

Even run-flat tiresburst Damage that causes the run-flat tire itself to fail, such as (burst), major damage with shoulder (sidewall) and wheel rim deformation, is rare.Therefore, the effect of the run-flat tire is tremendous even for a wide range of punctures to which the puncture repair agent does not work.Therefore, if the tread surface can be repaired with a normal tire, the run-flat tire can be repaired with a flat tire as well.

In addition, Spare tireIs no longer required, the trunk space is expanded, and the degree of design freedom is improved.[2][1], Improved fuel efficiency by reducing the weight of the vehicle (lightening by not loading spare tires> increased tire mass by running-flat tires)[2][3] (Since the run-flat tire itself is heavier than the normal tire and the rotational inertia mass increases, more energy is required for the tire inertia mass acceleration / deceleration during acceleration / deceleration, and the fuel consumption deteriorates accordingly).CO2There are merits such as reduction.In addition, the carScrapped carMost spare tires are discarded as they are, even though they are unused.[2][3], Since it becomes a big environmental problem, this problem can be solved.

Military applications

Run-flat tires were introduced in the 1930sCash transport vehicleDevelopment has begun as a technology that enables safe driving when commercial vehicles such as these encounter dangerous attacks such as shooting.[4]Soon broke outSecond World WarSo many military trucks,Armored personnel carrier,(English editionPopular as a battle tire[5].. In 1942Bead lock2 piece structure withCombat wheel (Combat Wheel) has also appeared, making it relatively easy to rearrange combat tires even in battlefields where the working environment is poor.[6]..Initially, combat tires(English editionType ofcontact areaHad, but todayMad terrain tiresA ground plane similar to is also used.Regarding defense performance, in the 1990sRussian FederationAdopted inBTR-90Take the one as an exampleSmall firearmBesides shooting(English editionIt is said that it can withstand the explosion of.For military use(English editionSuch as(English editionAlthough research and development has progressed, it has not threatened the dominant position of run-flat tires as of the 2010s.

Car competition

Motor sportsIn the world ofStock carThe highest peakNASCARBut built another tire inside the tireDouble tire (Lifeguard Inner Liner Safety Spare), And more than 1 mile per lapOval truckAll and out of the short trackBristol Motor SpeedwayIs obligatory to wear[7]..This structureGoodyear nailBy stepping on(English editionTo prevent a flat tire1930 eraMidfield[8]Announced in the double tire tube (Lifeguard Safety tube)[9]Is the base[10],Richard Petty(English editionWas appointed as a test driver and running tests were repeated.(English editionMore officially introduced[7].. In the mid-1960sMuscle carIn the heyday, the average lap speed was approaching 1 km / h on the Super Speedway with more than 2.5 miles per lap, and the introduction of double tires caused a flat tire while the cup car was lapped. SafelyPit laneMade it possible to return to[7].

Main types

Sidewall reinforced type
Most current run-flat tires are of this type[2][11][12]..It is a type that strengthens the rigidity of the shoulder part (sidewall) of the tire, and is also called a shoulder part strengthening tire.After the gas is released, this part maintains and supports the shape of the tire.[2][11]..Deterioration of riding comfort due to lack of elasticity[2][11][12]The difficulty is that it cannot withstand the load of heavy vehicles.BridgestoneIt was developed by a manufacturer centered on.
Core type
It was the first format to appear and is still the mainstream of combat tires.It is a type that has a structure (core) inside the tire, and after the gas is released, this structure maintains and supports the shape of the tire.[13]..The disadvantage is that the weight and cost are high because of the core.Michelin,Goodyear,ダ ン ロ ッ プ,PirelliAlthough it was developed by manufacturers such as, it has hardly spread to the extent that it is adopted by some vehicle models and vehicles with new transportation systems.
Auxiliary ring
A retrofit type core developed for the purpose of assisting the sidewall reinforced type, which is lightweight but weak against heavy loads.By attaching it to the rim of the wheel, it is possible to give running performance similar to the core type.Car,Prime Minister carSpecial to pick up and drop off guests and government officials, such as公用LimousineThen, such an auxiliary ring is used together so that stable high-speed driving can be continued even under a crisis such as shooting.

Tire pressure monitoring system

Even if a flat tire is punctured, the driver cannot detect it.For this reason, the tire pressure monitoring system (TPMS), And can be used in automobiles equipped with a system that lights a warning light when the air pressure drops due to a flat tire.Run-flat tires can be installed on cars that do not have this system, but basically the agreement stipulates the use of set tires.


Second generation

(2001-) is still under development, so the following points are inferior to normal tires.

  • Ride comfort and shock when passing over steps.
  • Increase in unsprung weight due to weight increase.
  • The number of products and distribution volume are small, and delivery delays and prices are high.
  • ス タ ッ ド レ ス タ イ ヤDue to the limited setting and the size, it is not possible to obtain domestic products, so it will be imported products for other countries.
  • The penetration rate of tire changers compatible with run-flat tires is low when changing tires.
  • In addition, since it is heavier than a normal tire, fuel efficiency deteriorates.

Third generation

(2010-) shows improvements to the shortcomings.In addition, BMW has implemented standard equipment (2003), and the market penetration rate is also improving.

  • Improved ride quality[11].. (100 hardness against normal 105)[14])
  • The fuel efficiency is improved by downsizing the engine and using a multi-speed automatic transmission, compared to the conventional normal tire model.
  • The sales price has decreased due to the increased penetration rate of run-flat tires, and the penetration rate of dedicated tire changers has improved.


In a Japanese car1999/Commercially availableNissan Hyper MiniEquipped as standard with TPMS at2001/,Toyota SoarerWas set as an option.afterwards,Lexus,Nissan GT-REquipment is being promoted mainly for high-priced passenger cars.BMWThen in 2003BMW 5 seriesRun-flat tires are standard equipment on all models except the M model.USA only2012/From the model, we are switching to selling both regular tires and run-flat tires.Initially, it has evolved from the second generation run-flat tires to the third generation, and the ride comfort that users have been dissatisfied with is also being improved.

The annual number of JAF punctures has exceeded 30 (2014) and is on the rise.The effect of run-flat tires is being recognized in the market to reduce the number of flat tires, and further spread is expected in the future.

Tire code

Different tire manufacturers have different symbols to indicate run-flat tires.Here, the symbol of the sidewall reinforced type, which is becoming established as a run-flat tire, is shown.


[How to use footnotes]
  1. ^ a b MFi 2009, p. 44.
  2. ^ a b c d e f g Masato Sakano 2008.
  3. ^ a b c Makoto Tsuruta 2012, p. 193.
  4. ^ “Fabric Inner Tube Lessens Blowout Hazards”. Popular Mechanics 63 (4): 488. (April 1935). https://books.google.com/books?id=wt8DAAAAMBAJ&pg=PA488&dq=Popular+Science+1935+plane+%22Popular+Mechanics%22&hl=en 2012/6/10Browse.. 
  5. ^ BF Goodrich (February 1944, 2). “The tire that eat bullets”. life: 49. 
  6. ^ Handling the Combat Wheel – WW2 Jeeps
  7. ^ a b c Race tire vs. street tire - ESPN.com
  8. ^ Goodyear "Ask your Dad if he has LIFEGUARDS" "(English edition』May 1938 issue,Boy Scouts of America, 29.
  9. ^ Goodyear "New Lifeguard Safety Tubes by Goodyear", Life, May 1952, 5, pp. 12-76.
  10. ^ Avert tragedy with Goodyear LifeGuard Safety Tubes - (English edition
  11. ^ a b c d Makoto Tsuruta 2012, p. 194.
  12. ^ a b MFi 2009, p. 45.
  13. ^ MFi 2009, p. 46.
  14. ^ "Toward the realization of a safer and more environmentally friendly car society" Run-flat tires have evolved to the third generation " (Press Release), Bridgestone Corporation, originalArchived as of October 2010, 12., https://web.archive.org/web/20101213231948/http://bridgestone.co.jp/info/news/2009030301.html 2020/3/16Browse. 


  • Masato Sakano "Current status and future of tires: About" run-flat tires "that can run a certain distance at a predetermined speed even if a flat tire is punctured," Japan Society of Mechanical Engineers, Vol. 111, No. 1075, 2008, pp. 506-507. , two:10.1299 / jsmemag.111.1075_506, ISSN 2424-2675.
  • Makoto Tsuruta "About" Run Flat Tires "", Journal of the Japan Rubber Association, Vol. 85, No. 6, 2012, pp. 193-197, two:10.2324 / gomu.85.193, ISSN 0029-022X.
  • "Tire technology that keeps running even if you get a flat tire" "Motor Fan illustrated』Volume 34, 2009, pp. 44-47.

Related item

  • (English edition ――In the form of diverting this military technologySelf-sealing tireWas developed.Applied to the inner surface of the tireSealant A tire whose (sealing agent) automatically closes a small flat tire.Continental is put into practical use.Bridgestone developed the product under the name of "McSeal" and Yokohama Rubber under the name of "Sealex".
  • (English edition --A tire with a mousse (sponge-like rubber) built into the tire.Even if you get a flat tire, the moose will support you and you can continue to run.Run on a rough roadRally,Off-roadraceAlthough it is used in, it has not been put into practical use for general driving.Used at construction sites and agricultural workWheelbarrow In (unicycles and cats), they are installed from the beginning under the name of no-puncture tires, and are also sold as replacement tires.
  • Presidential car (United States)


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