The present invention relates generally to the field of bicycle accessories and more specifically to an aerodynamic bicycle mounted fluid container.
Several liquid delivery systems for cyclists are well known including a removable bottle and cage mounted on a bicycle frame member, a reservoir adapted for attachment to a bicycle saddle rails or seatpost, a reservoir carried on a bicycle rider's back with a tube extending in front of the rider's face, and several pressurized and non-pressurized frame member liquid delivery systems.
Although the heretofore known liquid delivery systems have sufficed to provide liquid carrying and delivery for cyclists, many of the needs of enthusiasts, elite cyclists, mountain bicyclists, triathletes, and others seeking an aerodynamic design have not been addressed. These cyclists would benefit from a system that allows easy and continuous access to fluids without taking their hands off the handlebars or taking their eyes away from the road. It is desirable to provide an ability to refill the reservoir with another liquid source while riding, and to provide enhanced aerodynamic performance due to the design and placement of the reservoir. Given the cost of many of today's bicycles and the use of carbon fiber frames, it is desirable to provide a mounting system that is aerodynamic and does not leave a mark on the frame.
Bicycles are no longer constructed with frames of just cylindrical tubes. Several of today's elite bicycles have aerodynamically and structurally optimized frame members with varying cross sectional shapes. Therefore, there exists a need for a system that easily mounts on several different types of bicycles.
U.S. Pat. Nos. 5,115,952 (Jenkins) and 5,788,134 (Matic, Jr.) disclose frame member mounted fluid carrying systems that satisfy many of these needs. These systems do not allow easy refill and are not aerodynamically optimized either in term of their shapes or their attachment methods. Furthermore, their attachment methods can mark the frame.
U.S. Pat. No. 5,215,231 (Paczonay) discloses a reservoir mounted to a frame member with a tube that runs along a cyclist's back. This system keeps the cyclist attached to the reservoir and does not allow for the cyclist to easily mount and dismount the bicycle as is required in sports such as triathlon competitions.
U.S. Pat. No. 4,441,638 (Shimano) discloses an aerodynamically shaped water bottle and cage adapted for mounting on a frame member. This system still requires the rider to take his or her hand off of the handlebars to reach for the bottle. Doing so can cause in instability while riding, resulting in a crash causing injury or even death. Furthermore, the attachment methods can mark the frame.
Previously known fluid carrying systems devices have also used pressurized reservoirs. These systems also require a rider to interact with the system while riding, causing safety hazard. U.S. Pat. No. 5,143,390 (Goldsmith), for example, discloses a pressurized bottle that includes several elements that require communication with the rider.
U.S. Pat. No. 6,953,135 (Litton et al.) discloses a refill system that accepts commercially available bottles to refill a reservoir mounted below a bicycle seat. This system addresses many of the needs of an elite level cyclist or triathlete. However, wind tunnel tests suggest that this system provides poor aerodynamic performance because it increases the total aerodynamic drag as compared to a bicycle and rider alone.
Thus, there exists a need for a fluid carrying and delivery system that accommodates the needs of an elite level cyclist while addressing the safety concerns of recreational cyclists.
An illustrative embodiment of the invention provides an aerodynamic, hands free liquid container for mounting to a bicycle frame member. An embodiment of the container has rounded ends and a bottom portion that makes contact with a bicycle frame member and or mounting brackets. One end of the container is located closely behind the trailing edge of the bicycle's steering axis so the reservoir occupies a space that, but for the presence of the reservoir, is a turbulent wake region caused by the bicycle's head tube, steerer tube, handle bars and/or stem. In an illustrative embodiment the leading end of the container is located between about 0 cm and about 10 cm behind the trailing edge of the steering axis members. The presence of the inventive reservoir eliminates much of the turbulent wake in this region and reduces the aerodynamic drag on the bicycle.
The reservoir can be held in place by attachment elements such as straps, VELCRO®, zip ties, pipe clamps, or the like. In one embodiment, the front end portion is rounded and larger than the rear end portion. The container can be mounted to the top of the bicycle top tube directly behind the stem and handlebars for easy filling access and for providing an improved aerodynamic effect.
The container includes an opening for filling the container and another opening for receiving a flexible drinking tube. In an illustrative embodiment, the opening for filling the container can be closed with a removable cover.
The foregoing and other features and advantages of the present invention will be better understood from the following detailed description of illustrative embodiments, taken in conjunction with the accompanying drawings in which:
a is a top view of fluid flow around a cylinder representing a bicycle steering column frame members at racing speeds showing the wake region formed without the aerodynamic benefit of the reservoir according an illustrative embodiment of the invention; and
b is a top view of fluid flow around a cylinder representing a bicycle steering column frame member showing reattachment of airflow onto the fluid container.
An illustrative embodiment of a reservoir according to the present invention is adapted for mounting either on the top tube 6 or the down tube 7 of a bicycle. In
a shows a wake region 30 generated behind a tubular member representative of a bicycle head-tube 17 and/or steerer tube 18 as it passes through the air at a typical racing speed. The wake region 30 is a volume of turbulent air directly behind the tubular member. This wake region causes drag which slows the bicycle or requires increased rider effort to maintain speed. The free stream air in front of the handlebars 5 and stem 4 separates from the obstructing surfaces (steerer tube, handlebars) and becomes turbulent flows with Reynolds Numbers between 3×10̂3 and 3×10̂5 around a typical steering column. This airflow regime is typical for typical riding speeds, ambient wind speeds, and bicycle designs. This wake region continues downstream of the obstruction for several diameters or the tubular member. Empirical measurements in a wind tunnel have shown the turbulent wake to still exist 15 centimeters downstream of a 25.4 millimeter diameter steerer column. Airflow around steerer columns of larger diameters would cause turbulent wakes to continue proportionately farther downstream.
It is aerodynamically efficient to fill this wake region with a rigid volume, as shown in the illustrative embodiment of
In an illustrative embodiment, the reservoir 1 is designed to be manufactured using extrusion blow molding. Persons having ordinary skill in the art should understand that a variety of other manufacturing methods such as multi-component thermoplastic molding, carbon fiber manufacturing techniques and the like can be used within the scope of the invention. High or low-density polyethylene, polypropylene, or polycarbonate or a variety of other polymers or other materials could be used to manufacture the inventive container depending upon the desired material properties. Illustrative embodiments of the invention include a reservoir having a UV coating to protect it from material degradation over time, and/or a reflective coating or the like to reflect radiative heat and sunlight for keeping contents of the reservoir cool.
While the invention has been described with reference to an exemplary embodiment, it should be understood by those skilled in the art that various changes, omissions and/or additions may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, unless specifically stated any use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.
The present invention claims priority to U.S. Provisional Patent Application Ser. No. 60/810,311 entitled Aerodynamic Hands Free Liquid Container For Bicycles and The Like which was filed on Jun. 2, 2006 and which is hereby incorporated by reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US07/70324 | 6/4/2007 | WO | 00 | 7/2/2009 |
Number | Date | Country | |
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60810311 | Jun 2006 | US |