A TIRE

Abstract: A tire for automobiles, trucks, airplanes, etc. The tire has two treads which engage the road surface or like rolling surface, and comprises two toroidal bodies (3) and (4) of wire (2).

Description: A tire Technical Field The present invention relates to a tire for automobiles, trucks, aircraft etc., and more specifically to a tyre comprising two laterally spaced treads. Background of the Invention Many accidents occur each day as a result of punctures, tire- -explosions and aquaplaning. One method of reducing the risk of aquaplaning is to provide the tire with two treads spaced at a distance from one another. One such tire is known, for example, from US-A-3,830,273. Since this tire has two treads and a space therebetween, the total abutment or road- -engaging surface of the tire is reduced in relation to a conventional tire. This enables the tire to penetrate more readily collections of water on the road or like rolling surface. Any water present is forced upwardly into the interspace and the tire is therewith drawn by suction firmly against the road surface. Object of the Invention One object of the present invention is to provide a tire of the kind described in the introduction which is further improved and which has a more robust construction. Another object of the invention is to provide a tire which is so pliable that it will engage the road or like rolling surface with both treads even when heavily negotiating a curve. A further object is to provide a tire which is of such robust construction that it can be driven upon even in the absence of air-pressure therein, for example in the event of a puncture. Still another object is to provide a tire of such robust construction that the thickness of the rubber entailed can be reduced or a softer rubber used. Solution These objects are achieved with a tire of the kind described in the introduction which is characterized in that it comprises two toroidal bodies formed by a wire. The tire according to the proposed invention affords the ad¬ vantages provided by a broad tire with regard to stability at the same time as it is able to penetrate down to the road surface and therewith exert a good grip thereon, even when the road or like rolling surface is wet or when water has collected thereon. As a result of the proposed tire construction, the tire obtains a pliability such that if the tire is tilted when heavily negotiating a curve, the two tire treads will still hold contact with the road or like rolling surface, thereby ensuring good road-holding even in conditions such as these. The proposed construction also enables the tire, when suitably constructed, to be used with no air pressure therein, and hence a punctured tire does not prevent the vehicle concerned from being driven. The tire thus behaves in a safer manner than conventional tires also in this latter respect. Because of the toroidal bodies formed by a wire the rubber from which the tire according to the invention is formed need not be as thick as that of conventional tires, and hence the tire need not weigh more than a conventional tire and may even be lighter. It is also possible to use a softer rubber than can be used in conventional tires, thereby affording better road-gripping properties. Brief Description of the Drawings The invention will now be described in more detail with reference to two exemplifying embodiments thereof illustrated in the accompanying drawings. Fig. 1 is a radial sectional view of a tire according to the invention. Fig. 2 illustrates the construction of the winding in accordance with a first embodiment. Fig. 3 illustrates the construction of the winding according to a second embodiment. • Fig. 4 illustrates the construction of the winding according to a third embodiment. Description of Embodiments at Present Preferred The illustrated tire comprises two mutually indentical halves, having two identical road-engaging surfaces (treads). Each half comprises a toroidal body 3, 4 formed by a wire, which is the carcass of the tire. These toroidal bodies 3, 4 or solids of rotation are disposed in such way that their axes of rotation are in mutual alignment and in alignment with the axis of rotation of the tire and in such way that the distance between the middle planes of the bodies is smaller than the sum of circle radius of the solids of rotation, i.e. the radius of the circles giving the solids of rotations their form by rotation. Thus, the toroidal bodies are overlapping each other to form a third solid of rotation 15 of segment parts. Located between the two identical halves is a steel ring 1. A wire 2 made of spring steel is wound helically around the ring 1 according to one embodiment in a manner to form the two toroidal bodies 3 and 4 and the third solid of rotation 15 to form a smaller toroidal body 5 which encloses the ring. The steel ring 1 is provided with an aperture through which the wound wire can be threaded. The opening 6 can be closed subsequent to placing the wound wire in position and may be locked in its closed state. The manner in which the winding is formed is illustrated more clearly in Fig. 2, which shows the helical form in which the wire is laid in order to be threaded on the ring 1. The wire is formed with a loop 11 from which there extends an arcuate portion 12 which terminates in a further loop 13. The two loops 11 and 12 shall face one another. There is then formed in the wire a further arc 14 which is in mirror image with the firstmentioned arc 12. This pattern of loops and arcs is then repeated a number of times. The resultant wire winding is then fitted onto the ring 1, by threading the ring through the loops 11, 13 etc. lie close together in that part of the winding forming the smaller, toroidal body around the ring 1. In accordance with another embodiment shown in Fig. 3, the winding is formed from two spring-steel wires, each of which forms a toroidal body 3 and 4, each comprising exactly the same number of turns. The two bodies are then fitted one into the other, to form a third solid of rotation 15, in which each wire-section on both sides thereof borders on a wire- -section belonging to the other toroidal body. In accordance with a further embodiment shown in Fig. 4, the winding of the toroidal bodies 3, 4 consists of a plurality of closed rings of wire, which are disposed sequentially along a curved, circular line in a manner to form a toroid. These toroidal bodies 3, 4 then are brought together in overlapping relationship and forming a third solid of rotation 15. Further the closed rings can be connected to each other by means of attachments (not shown). The winding of the wire in said embodiments will effectively hold the ring 1 in its correct position between the two tire halves. The winding will also hold the two tire halves together strongly, so that they cannot be drawn apart and cause the tire to burst. The steel ring may alternatively comprise a closed ring devoid of the aperture 6, in which case the wire 2 is wound around the closed ring with - . - the aid of a suitable winding machine, to form the toroidal bodies in accordance with the example above. The construction proposed in accordance with the invention leaves a space between the two abutment surfaces. This interspace has a triangular- -like cross-sectional shape, with the apex of the triangle pointing towards the centre of the tire. The side lines of the triangle are defined partly by the road surface and partly by the outer cylindrical surfaces of the toroidal bodies 3 and 4. For the purpose of holding the steel winding correctly positioned and increasing the lateral stability of the tire, there is preferably placed in the aforesaid interspace a further ring 8 which is preferably made of steel and which is thinner than the ring 1 but of larger diameter than said ring, said further ring 8 being arranged in the triangular interspace at a deepest location in the apex pointing towards the centre of the tire. The ring 8 is provided with a closable opening, which enables the ring to be arranged in the interspace between the two toroidal bodies 3 and 4. A cord fabric 7 is then placed tightly against the toroidal bodies 3 and 4 so as to maintain the interspace therebetween. The cord-fabric layer may be relatively thin. The cord fabric 7 may comprise a conventional fabric wall, or a steel cord covered with rubber. A rubber tread is placed on the outside of the cord fabric. The tire bead is constructed in the same manner as with a conventionel tire, with a steel-wire core 6. The tire according to the invention can be fitted to a conventional wheel rim. Suitably, there is placed on the wheel rim a rubber piece 9 against which the two toroidal bodies 3 and 4 can lie. A space 10 will thus be formed between the rubber piece 9 and the toroidal bodies 3 and 4. Air is able to pass freely between the space 10, the voids in the toroidal bodies 3 and 4, and the relatively small space formed in the smaller toroidal body 5. The tire construction means that, in principle, air pressure can be excluded, due to the flexural strength of the wire windings. This also means that a puncture of crack in a tire will not prevent the venhicle concerned from being driven.

Claims: CLAIMS 1. A tire comprising two laterally spaced treads, characterized in that the tire comprises two toroidal bodies (3, 4) formed by wire (2). 2. A tire according to Claim 1, characterized in that the two toroidal bodies (3, 4) are equal in size. 3. A tire according to Claim 1 or 2, characterized in that the two toroidal bodies (3, 4) are disposed on the same axis of rotation, which is the normal to each of the middle planes of the toroidal bodies (3, 4), and in such way that the distance between the middle planes of the two toroidal bodies is smaller than the sum of circle radius forming the toroidal bodies, and thereby forming a third solid (15) of rotation which consists of segment parts of the toroidal bodies (3, 4). 4. A tire according to Claim 3, characterized in that each of the two toroidal bodies (3, 4) consists of a wire wound to a helical curve, which is bent to a toroid. 5. A tire according to Claim 3, characterized in that ech of the two toroidal bodies (3, 4) consists of a plurality of closed rings of wire, which are disposed sequentially along a curved line to from a toroid. 6. A tire according to Claim 3, characterized in that the two toroidal bodies (3, 4) and the third solid of rotation (15) are formed by one single wire wound as to form a further toroidal minor body (5) within the third solid of rotation (15). 7. A tire according to Claim 3, characterized in that the tire also comprises a ring (1) which is located in a plane perpendicular to the axis of rotation of the tire and having a diameter which is smaller than that of the treads. 8. A tire according to Claim 3, characterized in that the ring (1) is arranged in the third solid of rotation (15). 9. A tire according to Claim 7 , characterized in that the ring (1) is arranged in the toroidal, minor body (5). 10. A tire according to Claim 7, characterized in that a further ring (8) having a diameter smaller than that of the treads is located in the same plane as the first ring (1).

Inventors: JAKOBSSON IVAR, JAKOBSSON, IVAR
Applicants: JAKOBSSON IVAR, JAKOBSSON, IVAR
Application year: 1985
Main classification: B60C3
IPC codes: B60C3, B60C7