USRE28587E

USRE28587E - Tire and wheel assemblies

Info

Publication number: USRE28587E
Authority: US
Priority date: 1970-06-20
Filing date: 1974-04-05
Publication date: 1975-10-28
Also published as: NL7108328A; FR2100803A1; US3739829A; GB1359467A; LU63373A1; CH548877A; DE2130329A1; BE768616A; DE2130329B2; DE2130329C3; FR2100803B1; CA940814A

Abstract

A pneumatic tire and wheel assembly including a single chamber pneumatic tire in which is provided a flowable liquid lubricant to facilitate relative movement between the internal surface of the tire which come into contact when the tire is run under load in the deflated condition, of which the following is a specification.

Description

United States Patent [1 1 Powell et al.

[111 E Re. 28,587

[ Reissued Oct. 28, 1975 TIRE AND WHEEL ASSEMBLIES [75] Inventors: Leslie V. Powell, Lichfield; Reginald H. Edwards, Sutton Coldfield, both of England [73] Assignee: Dunlop Holdings Limited, England [22] Filed: Apr. 5, 1974 [21] Appl. No.: 458,134

Related US. Patent Documents Reissue of:

[64] Patent No.: 3,739,829

Issued: June 19, 1973 Appl. No.: 154,326 Filed: June 18, 1971 [30] Foreign Application Priority Data June 20, 1970 United Kingdom 30033/70 Apr. 3, 1971 United Kingdom 8592/71 [52] US. Cl. 152/330 [51] Int. Cl. 860C 5/00 [58] Field of Search 152/330, 346, 347

[56] I References Cited UNITED STATES PATENTS 4/1943 Benson 152/330 12/1971 Pace 152/327 Primary Examiner-James B. Marbert Attorney, Agent, or Firm-Stevens, Davis, Miller & Mosher [57] ABSTRACT A pneumatic tire and wheel assembly including a single chamber pneumatic tire in which is provided a flowable liquid lubricant to facilitate relative movement between the internal surface of the tire which come into contact when the tire is run under load in the deflated condition, of which the following is a specification.

37 Claims, 1 Drawing Figure Reissued Oct. 28, 1975 TIRE AND WHEEL ASSEMBLIES Matter enclosed in heavy brackets I: 1 appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates the additions made by reissue.

This invention relates to tire/wheel assemblies.

Upon partial or complete deflation of a pneumatic tire mounted on a wheel during the running of a vehicle oppositesurfaces in the interior of the tire and wheel assembly come into contact with one another under more or less load according to whether or not deflation is complete,.considerable heat is generated within the rubber and textile components of the tire and very rapid structural failure ensues.

One approach to this problem in the past has been to provide a second, independent, air chamber inside the tire so that if the tire is punctured the second chamber remains inflated and prevent the tire from collapsing and running on the rim. The disadvantages of this type of construction are that it is expensive and adds weight to the tire and hence adds to the unsprung weight ofa vehicle on which it is used. A grave problem is also that the inner chamber chafes on the interior of the outer chamber of the tire even, in the bead region at least, during normal running of the tire. To combat this problem it has been proposed to lubricate the surface of the inner chamber and/or inner surface of the outer chamber with a suitable coating. Low profile tires e.g. of aspect ratio 30 percent to 75 percent present a further problem in that the low sectional height allows little height for an inner chamber to prevent the tire bottoming on the rim.

The regions of the interior surfaces of a single chamber pneumatic tire which normally come into contact when running in the deflated condition are the interior surfaces of the tire close to but radially outwardly of the rim flange and the interior surfaces of the tire close to but radially-inwardly of the tread edgeQIt has been discovered that the major source of the heat generated which leads to the failure of the tire, is the relative movement of the interior surfaces of the tire which are in contact and under load.

According to the present invention a pneumatic tire and wheel assembly comprises a single chamber pneumatic tire wherein a flowable liquid lubricant is provided for the lubrication of the interior surfaces of the tire whereby in use of said assembly with the tire in a deflated or substantially under-inflated condition the relative movement between the interior surfaces of the tire in contact with one another is facilitated.

The liquid lubricant preferably is miscible with water so that leakage from a tire and wheel assembly onto a road surface can be washed away although a water insoluble lubricant can be used if desired. It is also desirable that the lubricant should not freeze at temperatures above C so as to withstand cold weather. The liquid lubricant may have a boiling point of at least 90C and preferably, in order to withstand high temperatures without severe loss through volatilization a liquid component of the lubricant has a vapor pressure of less than 50 mm of mercury at 140 C.

The liquid lubricant advantageously has a viscosity which is as high as is practicable to minimize lubricant loss through a puncture and assist in sealing a puncture bearing in mind the need for the lubricant to flow into the portions of the tire interior requiring lubrication. The preferred viscosity range for the liquid lubricant is 10,000 to 200,000 centistokes at 38C. Preferably also the lubricant although having a high viscosity has a low resistance to shear i.e. is a thixotropic material.

The liquid lubricant preferably has no deleterious effect on the rubber or other component of the tire carcass. If desired liquid lubricants which normally swell or otherwise affect rubber could be used by the use of a special impervious protective inner liner in the tire.

The liquid lubricant may, with advantage, contain a volatile liquid, which may or may not itself act as a lubricant for the rubber but which has a boiling point sufficiently low to appreciably volatilize at the temperature generated by running of the tire in a deflated or partly deflated condition. In this way the volatile liquid functions to partially re-inflate the tire and so reduce the high stresses generated in the sidewall due to the deflated or substantially deflated condition. Heat build-up in the tire is also lowered due to the reduced contact pressure and hence reduced frictional forces between the interior tire surfaces. The volatilizing of the volatile liquid also assists the dissipation of heat over the entire tire and rim surface. The volatile liquid has a vapor pressure at C above 200 mm. of mercury and may have a boiling point below for example C but preferably not below, for example 70 C in order that the liquid may be readily handled and not volatilized appreciably during normal running of the tire.

The volatile liquid, may itself be used to form the basis of the lubricant, e.g. an aqueous gel, although it is then particularly preferable to include in the lubricant some puncture sealing material in order to at least partly seal a puncture occurring in the tire to minimize the rate at which lubricant is lost from the tire.

Preferably the liquid lubricant containing a volatile liquid comprises a high boiling point lubricant, e.g. glycerol, and a volatile liquid which need not necessarily have good lubricating properties, e.g. water, so that if all the volatile liquid is lost as vapor from the tire the high boiling point lubricant remains. The liquids may or may not be miscible with each other.

In the case of liquid lubricants containing water as the volatile liquid viscosities in the range 10,000 to 200,000 centistokes, and good .lubricant properties can be achieved by the use of gelling agents such as those available under the trade names Natrosol, Polysteric BN4 and Carbopol. Viscous liquid lubricants such as gelled water-based lubricants have the added advantage that they assist in sealing a puncture at least against the low, e.g. 4 psi. pressures produced by vapor pressure inflation.

When the lubricant contains a volatile component it is most desirable that the lubricant should be capable of sealing the puncture. Thus the liquid lubricant may have incorporated therein a separate puncture-sealing or reducing material, for example, chopped cotton, wool, asbestos or synthetic fibers, e.g. of 0.0001 inch diameter and about 0.1 inch'long which acts to form a matted barrier over a puncture and is carried into position by escaping inflationary air and/or lubricant.

A liquid lubricant based on an aqueous gel may contain, for example, a freeze point lowering agent such as ethylene glycol or glycerol and agents to increase the lubricating power such as molybdenum disulphide,

isocrsable graphite powder and/or wetting agent or etergent such as Teepol.

It may be advantageous for the liquid lubricant to ave a formulation which enables the lubricant to be ample in the tire mentioned above using water as a volatile component at least 5 I: millimeters I milliliters of water should be used, although a considerably larger volume would generally be used to ensure a rapid increase in pressure in the,tire and allow for possible losses.

The liquid lubricant may be taken from a wide range of classes of compounds which are lubricants for rubber to rubber interfaces, for example:

e.g. arachis. castor. linseed. olive,

palm, rape. turkey red.

e.g. n'octanol.

e.g. diethyl sulphate, methyl caprylate.

Non-ionic surface active agents Cationic surface active agents Anionic surface active agents Polyglycols (sometimes called glycols.

polyethers, polyalkylene glycols or polyoxyalkylene glycols), e.g. "Ucon 5O HB-ZOOO and SO-HB-l'lO.

Dibasic acid esters e.g. dimethyl oxalate Chlorofluorocarbon polymers Silicones Silicate esters Fluoroe ste rs Neopentyl polyol esters Polyphenyl ethers Tetra alkyl silanes Ferrocene derivatives Tetra-substituted urea derivatives Heterocyclic derivatives Aromatic amines Hexafluorobenzene Soaps (e.g. sodium stearate) Alkalis (e.g. sodium hydroxide in weak LC of a detergent in a lubricant containing waterv A deaming agent may also be used in the lubricant com- )sition to control the extent of foaming, or if desired, event foaming.

A dispersant may be used when fibers are incorpoted in the composition.

The total amount of liquid lubricant in the tire is a inor proportion of the total volume of the tire, being preciably less, for example, that] than the large )lume of water used as ballast in agricultural and simir type tires which [as is a major proportion e.g. t'the interior volume of the tires. Such large volumes the present invention would be quite impractical n'ce they impair the running properties of the tire, cre- .e high rolling resistance and prevent the tire from sing used at anything other than low speeds. in the resent invention, the amount of liquid lubricant deands upon the lubricant used and the internal surface ea of the inflation chamber of the tire but for examle in a l85/60-l 3 radial ply car tire of internal volume oproximately 28 liters the total amount of lubrication ill generally be at least 75 millimeters] milliliters ut preferably less than e.g. l liter since above this volme the liquid is becoming undesirably heavy and ulky. This corresponds to between 105 and 1,300 :millimeters] milliliters oflubricant per square meter finternal surface area of the tire.

In the case of a lubricant containing a volatile comonent sufficient volatile component should preferably e present to generate in a volume at least 4 times that fthe inflation chamber of the tire a pressure of at least psi. at a temperature of for example, 68C. For Ex solutions).

Some examples of specific compounds which may be used are sodium carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, silicone oil, glycerol, propylene glycol, Teepol (a detergent commer cially available from Shell), Hederol" (a detergent commercially available from Proctor and Gamble), or mixtures thereof.

Examples of liquid lubricants containing a volatile component are solutions of detergents e.g. Teepol" in water, aqueous gels containing e.g. hydroxyethyl cellulose with or without a high boiling point such as glycerol, and mixtures of polyglycols or glycerol with water.

In addition to the puncture sealing and other additives previously mentioned the liquid lubricant may contain other substances such as antioxidants, to prevent oxidative attack on the lubricant, bactericide, wetting agent and viscosity index improver [r0] to broaden the range of temperatures at which the lubricant has a satisfactory viscosity.

In order to minimize the weight of lubricant required and any detrimental effects on the balance of the wheel/tire assembly the liquid lubricant preferably has a relatively low specific gravity e.g. a specific gravity less than 1.4.

In order to maintain a degree of lateral stability even when deflated, the tire preferably has a fairly low aspect ratio e.g. 30 percent to 75 percent and preferably 55 percent to percent and the width of the tire tread is preferably greater than the width of the wheel rim measured between the flanges. lf desired a tire having a cantilever sidewall construction may be used e.g. that described in I. U.K. Patent application No.

26702/70. U.S. Patent Application No. 145,610 filed May 21, 1971. The wheel rim upon which the tire is mounted is preferably a flat or substantially flat base rim without a well into which the tire beads can fall if they are displaced from their seats.

Two suitable types of rim which can be used are split rims, where the rim is divisible to permit mounting of a tire thereon and axially compressed rims which are rims produced initially with a well, the well being closed by axial compression after the tire has been mounted thereon, the latter type is shown in the accompanying drawing. When the rim has no well, if the beads become displaced from their seats in the ground contact area of the tire it is possible for them to be returned to their correct positions by the forces generated during rotation of the wheel in normal straight ahead driving although means for positively retaining at least the laterally outer bead in its seat may be provided if desired. lfa well-base rim is used, means are provided for retaining the beads in their seats, e.g. a bead spacer ring or removable studs or projections on the wheel rim.

Two particular examples of carrying out the invention will now be described with reference to the accompanying drawing of a cross section of a tire I mounted on a wheel rim 2 and containing liquid lubricant 3.

Two gelled solutions ofa water-based liquid lubricant were made up as indicated in Table 1 below:

TABLE I Solution Solution 1 (thin) 2 (thick) Teepol S (containing sodium salts of alkylaryl sulphonates and secondary alkyl sulphonates) 5 ml. 5 ml. Water 95 ml. 95 ml. 2% Belloid T.D. disperant (sodium dinaphthylmethane disulphonate 80% active made by Geigy) 5 ml. 5 ml. Asbestos (Canadian Group 7 l6 (Floats) very short low gl'lt 7 T.F.l. supplied by Johns-Manville) 2 g. 2 g. Defoamer C.V.P. (made by Cray Valley Products) 1 ml. 1 ml. Natrosol 260 H.H.R. thickener (watersoluble hydroxyethyl cellulose supplied by Hercules Powder Co. Ltd.) 1 g. l.5 g. Viscosity 10.000 100,000 centi centistokes stokes 500 [millimeters] milliliters of this lubricant was introduced into the inflation chamber of a pneumatic tire (size 185/60 X 13) mounted on a 3.5013 wheel rim (see drawing).

When a tire lubricated by means of the liquid as described above is deflated or substantially deflated, opposite parts of the interior surfaces of the tire or tire and wheel assembly come into contact and that part of the load of the vehicle which is supported by the tire and wheel assembly is carried by those surfaces, substantial relative movement taking place between them.

However, since the contacting surfaces are lubricated, the coefficient of friction is very low and little heat is generated, insufficient to cause structural damage or changes to the tire which might cause a rapid noticeable deterioration in the control of the vehicle. The vehicle on which the wheel and tire were mounted was thus enabled safely to travel substantial distances e.g. or more miles at a reasonable speed, eg 40 m.p.h.,

TABLE II Water 7U ml. Glycerol 30 ml. Natrosol I250 HHR. 2 gm. Hede rol (detergent made by Proctor & Gamble) l ml.

A l/60-l3 radial ply tire containing 300 millimeters of'this lubricant was run under 400 lbs load against a rotating drum at 50 m.p.h. and the drag generated by the tire i.e. its resistance to rotation was measured. The initial drag was 35.6 lbs but this value reduced steadily over the 10 minute run to a final figure of 20.1 lbs. After the 10 minutes the tire was found to be inflated to 3.5 psi.

Various further tests were performed using similar tires on the same test rig. In these tests however, the tires were run at 30 m.p.h. and the temperature generated in the shoulder of the tire were measured after 10 minutes and 20 minutes. To obtain a strict comparison between lubricating properties in these further tests care was taken to ensure that the tire did not become inflated.

Firstly, a series of tests was performed to investigate the effect of varying the amount of lubricant. Table III below gives the results obtained using as lubricant a polyalkylene glycol (available commercially as UCON oil) having a viscosity of 433 centistokes.

Table [V below gives the results obtained using as lubricant a 50/50 mixture of the polyalkylene glycol used in the tests in Table I and water.

Table V below gives the results obtained using as lubricant the glycerol/aqueous gel lubricant whose [formation formulation is given above.

TABLE V- Volume of Type/Viscosity Temperatures (C) after lubricant Centistokes at 38C Water/Glycerol/Nitrosol/Hederol l00,000 10 mins. mins. Ambient 300 c.c. (70/30) 90 110 18 200 cc. 108 122 20 c.c. H5 125 22 50 cc 125 I 22 tion may also be used with the inventions described in [U.K.] U.S. Patent application Nos. [30029/70, 30030/70, 30031/70, 30032/70 and 07024/71] 150,628,I50,561,150,564,150,560 allfiled on June 7, 1971 and 232,850 filed on March 8, I972.

The invention applies to tire and wheel assemblies in which the tire can be removed from the rim or, alternatively, when the tire is not removable therefrom i.e. the two form a permanent assembly, for example, when the rim is swaged over the tire beads after assembly of tire and rim.

temperature which after 10 minutes is as low as or lower than the other lubricants but after a certain level of temperature in. the .tireis reached the temperature begins to rise very rapidly so that after 20 minutes the temperatures of the water-containing tire has risen to 150 C which is approaching tire failure.

If lubricant should leak onto the road surface, when it is water-based or miscible with water it can be washed away by rainfall, so as to prevent the build-up of a hazard. to other road vehicles by the reduction of the coefficient of the road surface below a safe level.

When a liquid lubricant containing a volatile component is used it may be desirable to include in the wheel rim or tire a safety pressure release valve or other de vice e.g. a safety plug to prevent the tire from becoming over-inflated. However, as the increasing internal pressure increases the boiling point of the liquid lubricant, it is advantageous to design the lubricant so that its boiling point, at the maximum permissible tire inflation pressure has increased to above the maximum permissible generated temperature, so that boiling of the lubri cant stops before the tire can become severely overinflated.

In the present invention the liquid lubricant may be inserted directly into the inflation chamber of the tire before the tire and wheel assembly is sold, preferably, however, the lubricant is provided in an enclosing means which releases the lubricant into the tire upon deflation as described in I: U.K.] U.S. Patent application No. [30027/70] 150,627filed June 7, 1971 (interior lubricant container). Alternatively the lubricant may be injected into the tire after deflation as described in [U.K.] U.S. Patent application No. [30028/70] 150,562 filed June 7, 1971. The inven- TABLE VI Type Viscosity Centi- Temperature (C) after Stokes at 38C 10 mins. 20 mins. Ambient Glycerol 224 118 123 25 Propylene Glycol 46 l 15 26 Silicone oil 470 105 125 23/24 Silicone oil 20 H7 l3 0 22 Water 0.7 100 I50 20 UCON oil (polyalkylene glycol) 433 N7 l35 l9 It will be seen that water initially maintains a low We claim:

l. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising:

1. a wheel having a wheel rim with a pair of opposed annular flanges;

2. a pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges and in which the wheel rim upon which the tire is mounted is substantiallyflat based without a well into which the tire beads can fall if they are displaced from their seats, the rim being divisible to permit mounting ofthe tire thereon;

3. a flowable liquid lubricant which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

5. The pneumatic tire and wheel assembly of claim 1, i

in which the liquid lubricant includes some puncture sealingmaterial in order to at least partially seal a puncture occuring in the tire.

6. The pneumatic tire and wheel assembly of claim 1, in which the liquid lubricant has a specific gravity less than 1.4

7; The pneumatic tire and wheel assembly of claim 1, in which the tire has an aspect ratio between 30 percent and 75'percent.

8. The pneumatic tire and wheel assembly of claim 7, in which the aspect ratio of the tire is in the range 55 perce'ritto 70percent.

[9. The pneumatic tire and wheel assembly of claim 1, in which the wheel rim upon which the tire is mounted is substantially flat based without a well into which the tire beadscan fall if they are displaced from their seats, the rim being divisible to permit mounting of the tire thereon] [10. The pneumatic tire and wheel assembly of claim l, in which the wheel rim upon which the tire is mounted is produced initially with a well to permit mounting'of the tire on the rim, the well being closed by axial compression after the tire has been mounted thereon] 11. The pneumatic tire and wheel assembly of claim 7 1, in which the liquid lubricant contains a volatile liquid which has a boiling point sufficiently low to appreciably volatilize at the temperature generated by running of the tire in a deflated or partly deflated condition.

The pneumatic tire and wheel assembly of claim 1, in which the total amount of lubricant in the tire is in the range of 105 to 1,300 mls of lubricant per square meter of internal surface area of thetire.

13. The pneumatic tire and wheel assembly of claim I, in which the liquid lubricant has a formulation which enables the lubricant to be frothed or foamed by the violent agitation caused by rotation of the tire and wheel assembly.

14. The pneumatic tire and wheel assembly of claim l] l3 iincluding a [deforming defoa ming agent to claim l, in which the rim has an area of excess material bent. so as to leave the rim substantially without a well between the flanges.

16. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising:

a.,A wheel having a wheel rim with a pair of opposed annular flanges;

b, A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges, and in which the wheel rim upon which the tire is mounted is produced initially v with a well to permit mounting ofthe tire on the rim,

-. the well being closed by axial compression after the tire has been mounted thereon;

c-. A flowable liquid lubricant which, when theassembly is-used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

I 7. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising:

a. A wheel having a wheel rim with a pair of opposed annular flanges,

b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges;

c. A flowable liquid lubricant which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire, and in which the liquid lubricant contains a volatile liquid which has a boiling point sufficiently low to appreciably volatilize at the temperature generated by running of the tire in a deflated or partly deflated condition.

18; The pneumatic tire and wheel assembly of claim 17, in which the liquid lubricant is miscible with water.

19. The pneumatic tire and wheel assembly of claim 17. in which the liquid lubricant does not freeze at temperatures above 20 C.

20. The pneumatic tire and wheel assembly of claim 1 in which at least one liquid component of the lubricant has a vapor pressure ofless than 50 mm ofmercury at 140 c.

21. The pneumatic tire and wheel assembly of claim 17, in which the liquid lubricant includes some puncture sealing material in order to at least partially seal a puncture occurring in the tire.

22. The pneumatic tire and wheel assembly of claim 17. in which the liquid lubricant has a specific gravity less than 1.4. I

23.' The pneumatic tire and wheel assembly of claim I 17, in which the tire has an aspect ratio between 30% and 75%.

24. The pneumatic tire and wheel assembly of claim 23, in which the aspect ratioof the tire is in the range of 55% to v t 25. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising.

a. A wheel having a wheel rim with a pair of opposed annularflanges, and in which the rim has an area of excess material bent so as to leave the rim substan' tially without a well between the flanges;

b. A pneumatic tire having a tread portion whose width is greater than the width of wheel rim measured between the flanges;-

c. A flowable liquid lubricant which, when the assembly is 'used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

26. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising:

' a. A wheel having a wheel rim with a pair ofopposed annularflang es and a substantially flat base rim between said flanges so that the wheel rim is without a well into which the tire beads can fall, and a bead retaining means for restraining at least the laterally outer beadfrom moving from its seat;

b. A pneumatic tire havingan aspect ratio of between 30% and a tread portion whose widthis greater than the width of the wheel rim measured between the flanges and flowable lubricating material disposed on an interior surface of the tire which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

27. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising: 7

a. A wheel having a wheel rim with a pair ofopposed annular flanges, a pair of bead seats adjacent said flanges and a well to permit a tire to be mounted on the rim, means being provided for physically restraining the beads in their seats to prevent the tire beads from falling into the well, said means being movable to permit the tire to be dismountedfrom the rim;

. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges and aflowable lubricating material disposed on an interior surface ofthe tire, the en tire interior of said tire being free of intermediate supporting structure and the entire interior surface ofsaid tire being free ofinterrnediate protruding supporting structure so that when the tire is in a deflated condition opposed portions of the interior surface of the tire are movable relative to each other without generating an undue amount ofheat by means ofthe lubricating material, which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

28. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising:

a. A wheel having a wheel rim with a pair of opposed annularflanges and a substantially flat base rim between said flanges so that the wheel rim is without a well into which the tire beads can fall;

b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges, an aspect ratio between 30% and 75% and a flowable liquid lubricating material disposed inside the tire which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

29. The pneumatic tire and wheel assembly of claim 28, in which the lubricating material is miscible with water.

30. The pneumatic tire and wheel assembly of claim 28, in which the lubricating material does not freeze at temperatures above 20 C.

31. The pneumatic tire and wheel assembly of claim 28, in which at least one liquid component of the lubricating material has a vapor pressure of less than 50 mm ofmercury at 140C.

32. The pneumatic tire and wheel assembly of claim 28, in which the lubricating material includes some puncture sealing material in order to at least partially seal a puncture occurring in the tire.

33. The pneumatic tire and wheel assembly of claim 28, in which the lubricating material has a specific gravity less than 1.4.

34. The pneumatic tire and wheel assembly of claim 28, in which the aspect ratio ofthe tire is in the range of 55% to 70%.

35. The pneumatic tire and wheel assembly of claim 28, in which the total amount of lubricating material in the tire is in the range ofl to 1,300 mls. of lubricant per square meter of internal surface area of the tire.

36. The pneumatic tire and wheel assembly of claim 28, in which the lubricating material hasa formulation which enables the lubricant to be frothed or foamed by the violent agitation caused by rotation of the tire and wheel assembly.

37. The pneumatic tire and wheel assembly of claim 28, including a defoaming agent to control the extent of foaming.

38. A pneumatic tire and wheel assembly having a sinvgle inflation chamber capable of being run in a deflated condition comprising:

a. A wheel having a wheel rim with a pair of opposed annular flanges, a pneumatic tire mounted on the rim and having a pair of beads between the flanges and means on the rim to prevent the beads from becoming dislodged from the rim when run in a deflated condition;

. aflowable liquid lubricant which, when the assembly is used in a deflated condition, will facilitate relative movement ofcontacting interior surfaces of the tire, said liquid lubricant containing a volatile liquid which has a boiling point sufficiently low to appreciably volatilize at the temperature generated by running of the tire in a deflated or partly deflated condition and a puncture sealing material to at least partially seal a puncture occurring in the tire.

39. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having asingle inflation chamber comprising:

a. A wheel having a wheel rim with a pair ofopposed annular flange and a substantially flat base rim between said flanges so that the wheel rim is without a well into which the tire beads can fall, and a bead retaining means for restraining at least the laterally outer beadfrom moving from its seat;

b. A pneumatic tire having an aspect ratio of between 30% and a tread portion whose width is greater than the width of the wheel rim measured between the flanges and flowable lubricating material disposed on an interior surface ofthe tire, the entire interior ofsaid tire being free of intermediate supporting structure and the entire interior surface of said tire being free ofintermediate protruding supporting structure so that when the tire is in a deflated condition opposed portions of the interior surface of the tire are movable relative to each other without generating an undue amount ofheat by means ofthe lubricating material, which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

40. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising:

b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges, an aspect ratio between 30% and 75% and a flowable liquid lubricating material disposed inside the tire, the entire interior ofsaid tire being free of intermediate supporting structure and the entire interior surface ofsaid tire being free ofintermediate protruding supporting structure so that when the tire is in a deflated condition opposed par tions of the interior surface of the tire are movable relative to each other without generating an undue amount ofheat by means ofthe lubricating material,

which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surface of the tire.

Claims

1. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising: 1. a wheel having a wheel rim with a pair of opposed annular flanges; 2. a pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges(;) and in which the wheel rim upon which the tire is mounted is substantially flat based without a well into which the tire beads can fall if they are displaced from their seats, the rim being divisible to permit mounting of the tire thereon; 3. a flowable liquid lubricant which, when the assembly is used with the tire in a deflated condition, will facilitate relatIve movement of contacting interior surfaces of the tire.

2. a pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges(;) and in which the wheel rim upon which the tire is mounted is substantially flat based without a well into which the tire beads can fall if they are displaced from their seats, the rim being divisible to permit mounting of the tire thereon;

2. The pneumatic tire and wheel assembly of claim 1, in which the liquid lubricant is miscible with water.

3. The pneumatic tire and wheel assembly of claim 1, in which the liquid lubricant does not freeze at temperatures above -20* C.

4. The pneumatic tire and wheel assembly of claim 1, in which at least one liquid component of the lubricant has a vapor pressure of less than 50 mm of mercury at 140* C.

5. The pneumatic tire and wheel assembly of claim 1, in which the liquid lubricant includes some puncture sealing material in order to at least partially seal a puncture occuring in the tire.

7. The pneumatic tire and wheel assembly of claim 1, in which the tire has an aspect ratio between 30 percent and 75 percent.

8. The pneumatic tire and wheel assembly of claim 7, in which the aspect ratio of the tire is in the range 55 percent to 70 percent.

11. The pneumatic tire and wheel assembly of claim 1, in which the liquid lubricant contains a volatile liquid which has a boiling point sufficiently low to appreciably volatilize at the temperature generated by running of the tire in a deflated or partly deflated condition.

12. The pneumatic tire and wheel assembly of claim 1, in which the total amount of lubricant in the tire is in the range of 105 to 1,300 mls of lubricant per square meter of internal surface area of the tire.

13. The pneumatic tire and wheel assembly of claim 1, in which the liquid lubricant has a formulation which enables the lubricant to be frothed or foamed by the violent agitation caused by rotation of the tire and wheel assembly.

14. The pneumatic tire and wheel assembly of claim (1) 13 including a (deforming) defoaming agent to control the extent of foaming.

16. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges; b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges, and in which the wheel rim upon which the tire is mounted is produced initially with a well to permit mounting of the tire on the rim, the well being closed by axial compression after the tire has been mounted thereon; c. A flowable liquid lubricant which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

17. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges; b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges; c. A flowable liquid lubricant which, when the Assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire, and in which the liquid lubricant contains a volatile liquid which has a boiling point sufficiently low to appreciably volatilize at the temperature generated by running of the tire in a deflated or partly deflated condition.

18. The pneumatic tire and wheel assembly of claim 17, in which the liquid lubricant is miscible with water.

19. The pneumatic tire and wheel assembly of claim 17, in which the liquid lubricant does not freeze at temperatures above -20* C.

20. The pneumatic tire and wheel assembly of claim 17, in which at least one liquid component of the lubricant has a vapor pressure of less than 50 mm of mercury at 140* C.

22. The pneumatic tire and wheel assembly of claim 17, in which the liquid lubricant has a specific gravity less than 1.4.

23. The pneumatic tire and wheel assembly of claim 17, in which the tire has an aspect ratio between 30% and 75%.

24. The pneumatic tire and wheel assembly of claim 23, in which the aspect ratio of the tire is in the range of 55% to 70%.

25. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges, and in which the rim has an area of excess material bent so as to leave the rim substantially without a well between the flanges; b. A pneumatic tire having a tread portion whose width is greater than the width of wheel rim measured between the flanges; c. A flowable liquid lubricant which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

26. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges and a substantially flat base rim between said flanges so that the wheel rim is without a well into which the tire beads can fall, and a bead retaining means for restraining at least the laterally outer bead from moving from its seat; b. A pneumatic tire having an aspect ratio of between 30% and 75%, a tread portion whose width is greater than the width of the wheel rim measured between the flanges and flowable lubricating material disposed on an interior surface of the tire which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

27. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges, a pair of bead seats adjacent said flanges and a well to permit a tire to be mounted on the rim, means being provided for physically restraining the beads in their seats to prevent the tire beads from falling into the well, said means being movable to permit the tire to be dismounted from the rim; b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges and a flowable lubricating material disposed on an interior surface of the tire, the entire interior of said tire being free of intermediate supporting structure and the entire interior surface of said tire being free of intermediate protruding supporting structure so that when the tire is in a deflated condition opposed portions of the interior surface of the tire are movable relative to each other without generating an undue amount of heat by means of the lubricating material, which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

28. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges and a substantially flat base rim between said flanges so that the wheel rim is without a well into which the tire beads can fall; b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges, an aspect ratio between 30% and 75% and a flowable liquid lubricating material disposed inside the tire which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

30. The pneumatic tire and wheel assembly of claim 28, in which the lubricating material does not freeze at temperatures above -20* C.

31. The pneumatic tire and wheel assembly of claim 28, in which at least one liquid component of the lubricating material has a vapor pressure of less than 50 mm of mercury at 140*C.

34. The pneumatic tire and wheel assembly of claim 28, in which the aspect ratio of the tire is in the range of 55% to 70%.

35. The pneumatic tire and wheel assembly of claim 28, in which the total amount of lubricating material in the tire is in the range of 105 to 1,300 mls. of lubricant per square meter of internal surface area of the tire.

36. The pneumatic tire and wheel assembly of claim 28, in which the lubricating material has a formulation which enables the lubricant to be frothed or foamed by the violent agitation caused by rotation of the tire and wheel assembly.

38. A pneumatic tire and wheel assembly having a single inflation chamber capable of being run in a deflated condition comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges, a pneumatic tire mounted on the rim and having a pair of beads between the flanges and means on the rim to prevent the beads from becoming dislodged from the rim when run in a deflated condition; b. a flowable liquid lubricant which, when the assembly is used in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire, said liquid lubricant containing a volatile liquid which has a boiling point sufficiently low to appreciably volatilize at the temperature generated by running of the tire in a deflated or partly deflated condition and a puncture sealing material to at least partially seal a puncture occurring in the tire.

39. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising: a. A wheel having a wheel rim with a pair of opposed annular flange and a substantially flat base rim between said flanges so that the wheel rim is without a well into which the tire beads can fall, and a bead retaining means for restraining at least the laterally outer bead from moving from its seat; b. A pneumatic tire having an aspect ratio of between 30% and 75%, a tread portion whose width is greater than the width of the wheel rim measured between the flanges and flowable lubricating material disposed on an interior surface of the tire, the entire interior of said tire being free of intermediate supporting structure and the entire interior surface of said tire being free of intermediate protruding supporting structure so that when the tire is in a deflated condition opposed portions of the interior surface of the tire are movable relative to each other without generating an undue amount of heat by means of the lubricating material, which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surfaces of the tire.

40. A pneumatic tire and wheel assembly capable of being run in a deflated condition and having a single inflation chamber comprising: a. A wheel having a wheel rim with a pair of opposed annular flanges and a substantially flat base rim between said flanges so that the wheel rim is without a well into which the tire beads can fall; b. A pneumatic tire having a tread portion whose width is greater than the width of the wheel rim measured between the flanges, an aspect ratio between 30% and 75% and a flowable liquid lubricating material disposed inside the tire, the entire interior of said tire being free of intermediate supporting structure and the entire interior surface of said tire being free of intermediate protruding supporting structure so that when the tire is in a deflated condition opposed portions of the interior surface of the tire are movable relative to each other without generating an undue amount of heat by means of the lubricating material, which, when the assembly is used with the tire in a deflated condition, will facilitate relative movement of contacting interior surface of the tire.