Bicycle wheel rim for tubeless wheel

A bicycle wheel rim includes a rim having a hollow inner part and an outer part which is integrally formed with the inner part. An opening is defined in radial direction of the outer part. A connection unit is formed in the outer part and includes two seats located at an inner bottom of the opening, and two sidewalls extending from the two seats. Two engaging portions are respectively formed on the two seats and located apart from each other. Each sidewall has an outside, an inside and a top face which is connected between the outside and the inside. The inside is a flat inside without any lip or flange. The sidewalls have better strength and protect the sidewalls of the tire from being deformed.

BACKGROUND OF THE INVENTION

1. Fields of the Invention

The present invention relates to a bicycle wheel rim, and more particularly, to a bicycle wheel rim for tubeless wheel, the rim maintains pressure of the tire and reduces wind resistance and deformation.

2. Descriptions of Related Art

The conventional bicycle wheels generally comprise a rim and a tire is connected to the outer periphery of the rim. The tires of the bicycle wheels can be a tube or a clincher, wherein the tube has 0-shaped cross section, and the clincher includes a U-shaped cross section which includes two sidewalls and a lip is formed on each of the sidewalls. The clincher can be catalogued to be tube type or tubeless type.

The bicycle wheel rims includes a circular part with a hub located at the center of the circular part, and multiple spokes are connected between the inner periphery of the circular part and the hub. The rim cooperated with a clincher includes two sidewalls extending from two sides along the outer periphery thereof such that the lips of the tire are engaged with the two sidewalls. There is no tube located between the clincher and the rim so that the lips are required to be air-tightly connected to the sidewalls of the rim.

It is noted that when the tire is connected to the rim, the lips of the tire go over the edges of the sidewalls of the rim so as to mount the tire to the rim. The sidewalls of the tire are deformed when the lips go over the sidewalls, so that the sidewalls of the tires are weakened. Besides, in order to ensure no leakage between the lips of the tire and the sidewalls of the rim, each of the sidewalls of the rim is formed with an engaging portion which is used to be engaged with the lips of the tire. The engaging portion of each of the sidewalls of the rim makes the manufacturing cost increase, and the sidewalls of the rim are weakened and may be deformed by impact.

The present invention intends to provide a bicycle wheel rim that is cooperated with a clincher, and the bicycle wheel rim eliminates the shortcomings mentioned above.

SUMMARY OF THE INVENTION

The present invention relates to a bicycle wheel rim and comprises a rim having a hollow inner part and an outer part which is integrally formed with the inner part. The outer part has an opening defined in radial direction thereof. A connection unit is formed in the outer part and has two seats and two sidewalls which respectively extend from the two seats. The two seats are located at an inner bottom of the opening, and a bridge is connected between the two seats. The opening is defined between the two sidewalls and the seats. Two engaging portions are respectively formed on the two seats and located apart from each other. Each engaging portion is located a distance from the sidewall corresponding thereto. Each sidewall has an outside, an inside and a top face which is connected between the outside and the inside. The inside is a flat inside without any lip or flange. The sidewalls, the seats and the engaging portions secure lips of a tire.

The primary object of the present invention is to provide a bicycle wheel rim wherein the inside of each sidewall of the outer part is a flat inside without any lip or flange. The flat inside of each wall is easily manufactured and reduces deformation of the sidewalls of the tire when the tire is connected to the rim.

Another object of the present invention is to provide a bicycle wheel rim wherein each sidewall of the outer part does not have any lip or flange protruding therefrom such that the aero-assistance is reduced.

Yet another object of the present invention is to provide a bicycle wheel rim wherein each sidewall of the outer part does not have any lip or flange protruding therefrom such that the strength of the sidewalls of the rim is increased.

A further object of the present invention is to provide a bicycle wheel rim wherein each sidewall of the outer part does not have any lip or flange protruding therefrom, the contact area between the rim and the lips of the tire is increased so that the tire is air-tightly connected to the rim to avoid from leakage.

The present invention will become more apparent from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring toFIGS. 1 to 3, the bicycle wheel rim of the present invention comprises a rim10having an inner part11and an outer part12which is integrally formed with the inner part11. The inner part11is a hollow part. The outer part12has an opening defined in radial direction thereof.

A connection unit20is integrally formed with the outer part12and has two seats21and two sidewalls22which respectively extend from the two seats21. The two seats21are located at the inner bottom12of the opening, and a bridge is connected between the two seats21. The opening is defined between the two sidewalls22, the seats21and the bridge. Two engaging portions23are respectively formed on the two seats21and located apart from each other. Each engaging portion23is located a distance from the sidewall22corresponding thereto. Each sidewall22includes an outside221, an inside222and a top face223which is connected between the outside221and the inside222. Each inside222is connected to the top face223by a rounded edge. The inside222is a flat inside without any lip or flange extending therefrom. The sidewalls22extend perpendicularly relative to the axis of the bicycle wheel rim10. An angle α between 70 to 150 degrees is defined between each sidewall22and seat21corresponding thereto. In this embodiment, the angle α is 90 degrees.

Each sidewall22of the outer part12of the rim10does not have any lip or flange protruding therefrom so that the strength of the sidewalls22of the rim is increased and increases life of use of the rim10. The contact area between the rim10and the lips51of the tire50is increased so that the tire50is air-tightly connected to the rim10to avoid from leakage.

As shown inFIG. 4, the inner part11, the outer part12and the connection unit20are integrally formed as one-piece. The angle α between 70 to 150 degrees is defined between each sidewall22and seat21corresponding thereto. Each sidewall22extends a height ε of 2 to 8 mm from the seat21corresponding thereto. The width δ of 10 to 35 mm is defined between two respective insides222of the two sidewalls22. Each sidewall22has a thickness co of 1 to 2.5 mm A distance γ of 1 to (δ−5)/2 mm is defined between the inside222of each sidewalls22and the engaging portion23corresponding thereto. The distance γ is the width of each of the seats21. A rounded corner μ of 0 to 2 mm is formed at a connection portion between each of the sidewalls22and the seat21corresponding thereto. The height difference β is 0.1 to 1.0 mm is defined between the top point of each engaging portion23and the top surface of the seat21corresponding thereto. Each of the engaging portions23includes a curved protrusion o, and the curvature of the curved protrusion o is 0.3 to 2 mm A rounded curve v of 0.3 to 2 mm is formed at the connection portion between the curved protrusion o of each of the engaging portions23and the seat21corresponding thereto.

As shown inFIG. 5, the tire50(as disclosed in phantom lines) includes a first engaging ridge52formed on outer surface of each sidewall of the tire50, and the first engaging ridge52is located above the lip51of corresponding thereto. A second engaging ridge53is formed on inner surface of each lip51of the tire50. When in installation, one sidewall of the tire50is positioned inside of the outer part12, and the other sidewall of the tire50is deformed by applying a force thereto and positioned inside of the outer part12as shown inFIG. 6. The tire50is inflated so that the two sidewalls of the tire50expand and move toward the sidewalls22of the rim10. As shown inFIG. 7, when the tire50is inflated completely, the tire50is secured to the inside of the outer part12. The second engaging ridges53contact the engaging portions23. The first engaging ridges52are engaged with the top faces223of the sidewalls22of the rim10. Each lip51of the tire50is fully matched with the inside222and the top surface of the seat21.

The inside222of each sidewall22of the rim22is a flat inside without any protrusion so as to form an L-shaped room to accommodate the lip51of the tire50.

The advantages of the present invention includes the following advantages which are that there is no flange or lip extending from the sidewalls22of the rim10, the structure of the rim10becomes simple and easily to be manufactured.

The machine and equipment to be used to manufacture the rim10is simplified and therefore reduce the manufacturing cost.

The lips51of a tire50to be installed to the rim10are put in the outer part12so that the sidewalls of the tire50are not deformed severely. The volume in the tire50is increased and the rolling resistance is reduced.

The sidewalls22of the rim10do not have any protrusion so that the strength of the rim10is reinforced which increases life of use of the rim10.

The lips51of the tire50installed to the rim10of the present invention are matched to the insides223of the sidewalls22and the top surfaces of the seats21. The contact area between the lips51and the outer part12is increased and has better air-tight features, so that the leakage can be avoided.

As shown inFIG. 8, the angle α is an obtuse angle which is larger than 90 degrees, and the lips51of the tire50can also be matched with the insides222and the top surfaces of the seats21.

The rim10of the present invention does not have any lip or flange extending from the sidewalls22of the outer part12, the structure is simplified and includes more advantages than the conventional rims as mentioned above.