Patent Application
20060027298
The present invention relates to hollow ethylene-vinyl acetate (EVA) foam tires having an enhanced wheel core and a rim for being clamped on both sides, such that the three parts can be connected more securely as to enhance the loading capacity of the tire.
In general, a solid tire made of ethylene-vinyl acetate (EVA) foam material is commonly used for vehicles carrying less load and having no absorber but demanding a good shockproof function, because such tire has the features of low cost, easy manufacturing and outstanding elasticity. Although the tire of this kind is solid, the carrying capacity is still insufficient due to its manufacturing material. However, the U.S. Pat. No. 4,216,810 disclosed a tire structure which comprises a plurality of annularly disposed circular protector elements keeping an appropriate distance from the inner wall of the wire and a flange being accommodated precisely between both inboard sides of the tire. When the inboard rim and the outboard rim are engaged, the corresponding flanges of the two rims are clamped, and thus the protector elements can be mounted into the tire. However, the main purpose of the protector element is to support a vehicle by the protector elements in a tire particularly when the tire is punctured, such that when the flat tire is pressed and in contact with the ground, the tire and the rim will not be in direct contact, and the vehicle can continue its traveling without damaging the tire and the rim. Such arrangement allows a flat tire to travel more stably without skids.
Although a pneumatic tire with this structure has better elasticity and cushioning effect, its carrying capacity is still very limited. Furthermore, the pneumatic tire also has the risk of being punctured and flatted.
It is therefore a primary objective of the present invention to overcome the condition of maintaining a good elastic and loading capability of a tire without air inflation. The tire according to the present invention is made of EVA materials and substantially hollow, and the tire comprises a wheel core in an annular shape formed by a plurality of separated sections and a rim clamped on both sides of the tire. In addition to strengthening the structure of the EVA tire, the present invention also enhances its loading capacity and also maintains an excellent elasticity.
Further, a protruded section disposed on the two corresponding inboard sides of the foregoing rim and the sides of the wheel core are substantially hollow, such that the tire can engage the rim and wheel cores better as to further prevent the EVA foam tire from skidding.
The technical measures adopted by the invention to achieve the foregoing objectives, the hollow foam tire installs a hollow wheel core on the side of the tire in advance, and the wheel core is comprised of a plurality of circular sections and both sides of the tire are clamped by the rim and a pointed splinter disposed on the surface where the rim and tire are in contact with each other is pierced into the tire, and a protruded block section for corresponding and engaging with each other is disposed on the internal surface of the wheel core and the surface corresponding to the flange section of the two rims.
The invention can be fully understood by the following description accompanied with the drawings of a preferred embodiment of the present invention.
Please refer to
Please refer to
A tire 4, substantially has a design in a hollow shape with two corresponding internal flange sections 41 disposed on the internal sides of the tire 4 and an accommodating space 42 defined between two internal flange sections 41.
A wheel core 3 comprises a plurality of separated sections 3a, 3b, 3c, 3d aligned in a circular shape, a hollow section 31 disposed on the intervals between separated sections 3a, 3b, 3c, 3d, a wider flange section 32 disposed on the internal side on both sides of each separated section 3a, 3b, 3c, 3d, and a plurality of protruded block sections 33 disposed at intervals on the internal surface of the flange section 32.
Two corresponding wheel rims 5 are installed on both sides of the tire 4. Besides having an axle hole (not labeled in the figure) for passing a wheel axle through, the external side also has a convexly curved flange surface 51 and a plurality of pointed splinters 52 disposed on the flange surface 51, a flange end 53 disposed on the internal sides of the rim 5 and a plurality of protruded block sections 54 disposed at intervals on the external surrounding surface of the flange end 53.
The wheel core 3 comprised of separated sections 3a, 3b, 3c, 3d is preinstalled into the hollow tire 4, and the two corresponding rims 5 are installed onto both internal sides of the tire 4 and the two corresponding rims 5 are coupled together by screws, so that the flange ends 53 of the two rims 5 are extended into the foam tire 4 and the external flange surface 51 of the rim 5 is attached onto the external side of the internal flange section 41 of the foam tire 4. The accommodating space 42 disposed between two internal flange sections 41 of the foam tire 4 precisely locates the lower neck section of every separated section 3a, 3b, 3c, 3d of the wheel core 3. In the meantime, the flange section 32 of each separated section 3a, 3b, 3c, 3d is extended onto the flange end 53 of the rim 5, so that the corresponding protruded block sections 33, 54 between the two are engaged alternately. Therefore, the two corresponding rims 5 secured by screws are moved inwardly as to clamp the internal flange section 41 of the foam tire 4 between the external flange surface 51 of the rim 5 and the wheel core 3. In the meantime, each pointed splinter 52 of the external flange surface 51 of the rim 5 will pierce into the foam tire 4, and the internal flange section 41 of the foam tire 4 will be embedded into the hollow hole 31 on the side of each separated section 3a, 3b, 3c, 3d at the contact position of the internal flange section 41 of the foam tire 4 and the side of each separated section 3a, 3b, 3c, 3d when the flange section 41 is pressed. Therefore, the foam tire 4 is clamped and fixed, and also positioned by the engaging the pointed splinters 52 and the hollow holes 31, so that the foam tire 4, the rim 5, and each separated section 3a, 3b, 3c, 3d (or the wheel core 3) will not have any skid at all. In the mean time, since the protruded block sections 54 on the surface of the flange ends 53 of the rim 5 and the protruded block sections 33 on the internal sides of each separated section 3a, 3b, 3c, 3d are coupled alternately for the positioning effect, therefore there is a slippery-proof effect between the rim 5 and the wheel core 3. Thus, the design according to the present invention separates the wheel core 3 from the rim 5 instead of directly forming the wheel core 3 onto the rim 5, which saves the cost of the molding and the trouble of the operation, and also allows users to freely assemble or remove the rim 5, the tire 4 or the wheel core 3, which provides a more flexible way of installing or removing any parts for the maintenance.
While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.
