JP6417286B2 - Amphibious tire rim assembly - Google Patents

Description

  The present invention relates to a tire rim assembly constituting a wheel used in an amphibious vehicle.

  Amphibious vehicles that enable surface and land travel are used as emergency vehicles, water rescue vehicles, disaster response vehicles, and the like.

  In such a vehicle, normal driving may be hampered or impossible due to the occurrence of a situation that may interfere with lifesaving or disaster response, such as air leaks associated with tire punctures (slow punctures). It is desirable to avoid this as much as possible. As a method for avoiding such a situation, for example, a tire of a tire rim assembly attached to an amphibious vehicle may be a non-punctured tire (solid tire) instead of a pneumatic tire.

  2. Description of the Related Art Conventionally, as an example of a no-puncture tire, a tire that is attached to a rim and defines a lumen in cooperation with the rim, and a closed-cell foam having elasticity that is disposed so as to fill the lumen is provided. Has been proposed (see Patent Document 1 below).

  According to this, even when the tire is cracked due to, for example, a foreign object sticking into the tire, there is no air leakage as in a pneumatic tire, and the tire includes a load supporting function by the foam. These functions are maintained, so that normal driving on land can be maintained. In addition, even if the crack may be immersed in and inside the foam, the water immersion in the closed-cell foam is limited to a part of the surface area without reaching all of it. The function of imparting buoyancy to the amphibious vehicle of the tire when traveling on water is not lost.

  However, the no-puncture tire is not sufficient for absorbing and mitigating impacts caused by road surface irregularities generated when the amphibious vehicle travels on land. For this reason, although the conventional no-puncture tire allows normal travel on land of amphibious vehicles, it is not sufficient in terms of ride comfort. Moreover, unlike the air in a pneumatic tire, the foam that supports the full load of the vehicle is likely to break during long-term use.

Japanese Patent Laid-Open No. 9-300426

  Accordingly, an object of the present invention is to provide a tire rim assembly suitable for use in an amphibious vehicle.

  The present invention relates to a tire rim assembly for an amphibious vehicle, wherein the tire rim assembly covers a rim, a tire mounted on the rim, an inner peripheral surface of the tire, and is in close contact with the inner peripheral surface. A non-water-permeable coating having elasticity, an elastic foam which is disposed in the lumen defined by the rim and the coating and occupies the lumen leaving an annular void between the rim, and the void is filled Pressurized air.

  In one embodiment of the present invention, the coating is made of a closed cell type elastic foam, and the elastic foam occupying the lumen is an open cell type.

  In another embodiment of the present invention, the elastic foam is composed of a plurality of pieces arranged in the tire circumferential direction, each of the plurality of pieces has a pair of side surfaces facing each other in the tire circumferential direction, and each of the plurality of pieces is Are in contact with each other on one of the side surfaces of each other and exert elastic force on each other. Each piece may have its entire surface covered with a non-permeable coating.

  In the present invention, the elastic foam and the pressurized air occupy the lumen defined by the coating covering the rim and the inner peripheral surface of the tire, and both the elastic foam and the pressurized air jointly Supports the load of dual-purpose vehicles. For this reason, the load burden of the said elastic foam is small compared with the case where an amphibious vehicle is supported only by an elastic foam. From this, it is possible to extend the life of the elastic foam or prolong its use period. Further, the pressurized air performs the same function as air in a so-called pneumatic tire, and gives good ride comfort, steering stability, high-speed stability, and the like by the amphibious vehicle. These riding comfort and running performance are useful for ensuring emergency response, quickness, safety, etc. particularly required for emergency vehicles, water rescue vehicles, disaster response vehicles, and the like.

  Further, a part of the pressurized air in contact with the elastic foam enters and exits the elastic foam, or passes through the elastic foam and reaches the boundary between the elastic foam and the coating. Finally, a plurality of dispersed air reservoirs and a plurality of continuous air regions are formed at the boundary. A part of the pressurized air entering and exiting the elastic foam and the air reservoir or air layer formed through the elastic foam serve to further enhance the elastic function of the elastic foam. Due to the function, the amphibious vehicle can be further improved in ride comfort and handling stability. Further, even when the tire is cracked when the amphibious vehicle is running on land, the elastic foam supports the load of the amphibious vehicle even if the pressurized air leaks out of the tire through the covering, and the amphibious vehicle It serves to maintain the dual-purpose vehicle running on land.

  Further, the elastic foam and the pressurized air serve to give buoyancy to the amphibious vehicle at the time of traveling on water, and contribute to the improvement of the traveling performance of the amphibious vehicle. In addition, even when the tire has a crack generated during the land running, a water-impermeable coating that covers and closely contacts the inner peripheral surface of the tire suppresses intrusion of water into the tire, Prevents hydrolysis and concomitant collapse of the elastic foam.

  In the one embodiment of the present invention, the water-impermeable coating is made of a closed-cell elastic foam. Unlike the open-cell elastic foam, the closed-cell elastic foam differs from the open-cell elastic foam in that the plurality of bubbles constituting it are independent in a non-communication state. For this reason, water cannot move along an independent bubble. From this, the closed-cell elastic foam has a water-impermeable property and functions to prevent water entering through the cracks generated in the tire from entering the closed-cell foam.

  In another embodiment of the present invention, the elastic foam can be more easily arranged in the tire before being attached to the rim by configuring the elastic foam as a plurality of pieces. it can. Each of the plurality of pieces has a pair of side surfaces opposed to each other in the tire circumferential direction, in contact with each other on both side surfaces, and in addition, exerts elastic force on each other. Therefore, the plurality of pieces are maintained in a state aligned in the tire circumferential direction without slipping out inward in the tire radial direction, which contributes to supporting the load of the amphibious vehicle. In addition, when the entire surface of each piece is covered with a coating that is a water-impermeable coating, the coating functions to prevent water from entering each piece. Further, even if a crack generated in the tire extends not only to the tire but also to the elastic body, the remaining other pieces except the one piece that has received the crack support the load of the amphibious vehicle. Work.

1 is a partial cross-sectional view of a tire rim assembly for an amphibious vehicle. However, in order to avoid complication of the drawing, hatching to be applied to the tire in the tire rim assembly is omitted. FIG. 2 is a schematic cross-sectional view of a plurality of elastic foams coated with a water-impermeable coating.

  Referring to FIG. 1, a part of a tire rim assembly forming part of a wheel suitable for an amphibious vehicle, particularly an amphibious vehicle (not shown) used as an emergency vehicle, a water rescue vehicle, a disaster countermeasure vehicle, etc. In FIG.

  The tire rim assembly 10 includes a rim 12, a tire 14 attached to the rim, an elastic water-impermeable coating 18 that covers and closely contacts the inner peripheral surface 16 of the tire, and a rim. 12 and the tire 14 are jointly defined in an inner cavity 20, and an elastic foam 24 occupying the inner cavity 20 leaving an annular cavity 22 between the rim 12 and pressurized air filled in the cavity 22. 26. An inner peripheral surface 16 of the tire 14 is defined by an inner liner (not shown) attached to the tire 14.

  The tire 14 is a reinforcing band that is disposed between a plurality of carcass 28 constituting the skeleton, a bead portion 30 that fixes both ends of the carcass 28, a tread portion 32 of the tire 14, and the carcass 28, and extends in the tire circumferential direction. A plurality of belts 34. The tire 14 is in airtight contact with the bead sheet 12c between the flange 12a of the rim 12 and the bumps 12b at the bead portion 30 thereof. The rim 12 includes an air valve (not shown) for filling the gap 22 with the pressurized air 26.

  The elastic foam 24 and the pressurized air 26 in the tire 14 jointly support the load of the amphibious vehicle. The pressurized air 26 reduces the load burden on the amphibious vehicle 24, extends the life of the amphibious vehicle 24, and improves the ride comfort and handling stability of the amphibious vehicle.

  The covering 18 is formed by the penetration of water into the tire 14 through a crack, which may occur in the tire 14 due to trauma during the land travel of the amphibious vehicle, and the elastic foam 24 accompanying this. Prevents disintegration due to hydrolysis.

  The illustrated coating 18 is made of a closed-cell elastic foam. The closed-cell type elastic foam has a non-water-permeable property in which a plurality of bubbles constituting it are independent from each other in a non-communication state and do not allow water to pass through. Further, since the covering 18 has elasticity, it can be elastically deformed following the elastic deformation of the tire 14 when the amphibious vehicle travels on land.

  In the present invention, “elastic foam” means “foam” having elasticity. Further, “foam” broadly means a polymer foam, and in practice, a plastic foam (plastic foam) is used as the foam. Moreover, the kind of plastic for forming the said plastic foam is not ask | required. The closed cell type elastic foam constituting the coating 18 is preferably made of a foam of ethylene propylene diene rubber (EPDM) (for example, Everlite Moran (trademark) manufactured by Bridgestone Corporation). The elastic foam 24 is made of ester polyurethane, preferably ether polyurethane.

  The elastic foam 24 is an open-cell type in which a plurality of bubbles constituting the elastic foam 24 are continuous. For example, the elastic foam 24 is made of urethane foam. The elastic foam 24 is formed on the inner peripheral surface 16 of the tire 14, more specifically on the surface 24 a that follows or follows the shape of the back surface 18 b of the coating 18, and the periphery of the portion between the bumps 12 b on the rim 12. And a cylindrical peripheral surface 24b surrounding the portion at a distance. Therefore, the elastic foam 24 is in contact with the pressurized air 26 on the peripheral surface 24b. The size of the interval between the peripheral surface 24b of the elastic foam 24 and the portion between the bumps 12b of the rim 12 can be arbitrarily determined.

  A part of the pressurized air 26 flows into the elastic foam 24 through the peripheral surface 24b of the elastic foam 24, more specifically, into the open cells of the elastic foam 24, and out of the open cells. Furthermore, a part of the pressurized air that has flowed into the elastic foam 24 passes through the open cells, reaches the boundary between the elastic foam 24 and the coating 18, and a plurality of air is interposed between the elastic foam 24 and the coating 18. Disperses as a pool or multiple continuous air regions. Part of the compressed air 26 enters and exits the elastic foam 24 and the air reservoir and air region give the elastic foam 24 good elasticity, which improves the ride comfort and handling stability of the amphibious vehicle. Further improvement is achieved.

  The elastic foam 24 can be of the closed cell type instead of the illustrated example of the open cell type. The size of molecules constituting air is extremely small compared to the size of molecules constituting the closed-cell elastic foam. For this reason, although it is quantitatively smaller than the open-cell elastic body, it enters and exits the closed-cell elastic foam, and reaches the boundary via the closed-cell elastic foam. Is possible.

  Therefore, when the crack is generated in the tire 14, the pressurized air 26 leaks out of the tire 14 from the crack through the elastic foam 24 and the coating 18. In this case, the amphibious vehicle can travel on land with the load supported by the elastic foam 24.

  The elastic foam 24 and the pressurized air 26 give buoyancy to the amphibious vehicle when traveling on the water, and contribute to the improvement of the water traveling performance of the amphibious vehicle. Further, when a crack occurs in the tire 14, the water that tries to enter through the crack is stopped by the water-impermeable coating 18, and water immersion into the elastic foam 24 is prevented.

  As shown in FIG. 2, the elastic foam 24 may be composed of a plurality of pieces 36 arranged in the tire circumferential direction instead of the example shown in FIG. 1. In the illustrated example, the entire surface of each piece 36 is covered with a water-impermeable coating 38. Each of these pieces 36 has a pair of side surfaces 36a opposed to each other in the tire circumferential direction, and is in contact with each other on one of both side surfaces 36a through a coating 38. The plurality of pieces 36 exert elastic force on each other in the tire circumferential direction via the coating 38.

  Both side surfaces 36a of each piece 36 facing each other in the tire circumferential direction are on two virtual surfaces (not shown) including the axis of the tire 14 and extending in the tire radial direction, and the pieces 36 are tires. They are elastically pressed in the circumferential direction. Accordingly, the individual pieces 36 are prevented from moving inward in the tire radial direction, and the plurality of pieces 36 are maintained in an aligned state in the tire circumferential direction, and support the load of the amphibious vehicle.

  In this example, even when the crack extends not only to the tire 14 but also to the coating 18, the coating 38 can prevent water from entering the piece 36. Further, even if the crack further extends to the coating 38 and the piece 36, the piece is a part of the plurality of pieces. Can be supported. Thereby, traveling on land and water can be enabled.

The hardness of the elastic foam 30 is preferably set to 190 to 570 N (please tell me the correct unit) in order to give the amphibious vehicle the above-mentioned riding comfort and running performance. The hardnesses 190N and 570N are sizes that cause 75% strain when stresses of 600N and 1000N are applied to the first layer 30, respectively. Moreover, in order to provide such a hardness, the density of the first foam 30 is set to 60 to 70 Kg / m ³ . Setting the density in this range is also preferable in that the buoyancy imparted to the amphibious vehicle when traveling on water can be made relatively large.

DESCRIPTION OF SYMBOLS 10 ... Amphibious vehicle tire rim assembly, 12 ... Rim, 14 ... Tire, 16 ... Lumen, 18 ... Cover, 20 ... Lumen, 22 ... Gap, 24 .. Elastic foam, 26 ... pressurized air, 36 ... piece, 38 ... coating.

Claims (3)

With the rim,
A tire mounted on the rim;
An elastic, water-impermeable coating that covers and closely contacts the inner peripheral surface of the tire;
An elastic foam disposed in the lumen defined by the rim and the covering and occupying the lumen leaving an annular gap between the rim;
Including pressurized air filled in the gap ,
The amphibious vehicle tire rim assembly, wherein the covering is made of a closed-cell elastic foam, and the elastic foam occupying the inner cavity is an open-cell elastic foam . With the rim,
A tire mounted on the rim;
An elastic, water-impermeable coating that covers and closely contacts the inner peripheral surface of the tire;
An elastic foam disposed in the lumen defined by the rim and the covering and occupying the lumen leaving an annular gap between the rim;
Including pressurized air filled in the gap ,
The elastic foam comprises a plurality of pieces arranged in the tire circumferential direction,
Each of the plurality of pieces has a pair of side surfaces facing the tire circumferential direction,
An amphibious vehicle tire rim assembly in which a plurality of pieces are in contact with each other on one of both side surfaces and exert elastic force on each other . The tire rim assembly for an amphibious vehicle according to claim 2 , wherein each piece is covered with a coating having a water-stopping property on the entire surface.

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