1. Field of the Invention
The instant disclosure relates to bicycle brake light system, and pertains particularly to a self-powered conformal brake light system for bicycle.
2. Description of Related Art
Visual signaling devices have been widely employed on motor vehicles to increase visibility thereof and thereby enhance safety. Electrical lighting devices, in particular, are effective sources of visual signal. Numerous types of lighting equipment have been developed and implemented on motor vehicles with little trouble because motor vehicles usually include onboard power generators that can provide necessary power to the lighting devices. In contrast, human-powered vehicles, such as pedal-driven bicycles or tricycles, often do not comprise onboard electricity generating equipment. Therefore, traditionally, these vehicles rely heavily on light reflective elements as their precautious signaling device. However, as these environmentally friendly means of transportation share the roads with other motor vehicles, the safety of their operators and passengers will be greatly enhanced by adequate onboard active lighting devices.
A brake light is one of the most essential types of safety signal. It signals a driver's intention to decelerate as the vehicle's brake system is engaged. Conventional bicycle brake light designs often involve direct placement of switch actuators on the brake shoe, as disclosed by U.S. Pat. No. 3,878,387 to Kovacic. Newer designs incorporate brake cable activated micro-switches for engaging the brake lights. U.S. Pat. No. 5,739,750 to Drake and U.S. Pat. No. 4,833,444 to Wisniewski are iconic examples for such brake light designs. While the conventional designs intuitively utilize the change in brake cable tension or the movement of the brake shoe as the source for actuating brake light switches, the primitive actuating arrangements often cannot compensate for the wear and tear of the brake system, therefore making it difficult to maintain the brake light system in optimal operating status. Moreover, most conventional brake light systems require self-contained power supplies (in most cases dry cell batteries). Thus, careful monitoring of the battery level becomes imperative for ensuring proper operation of the conventional brake light devices.
China Patent CN200820239332.5 to Tao discloses a self-powered bicycle brake light arrangement. Specifically, Tao teaches a power generator driven by a set of gears attached to the brake shoe of the bicycle brake. However, skilled artisans would easily recognize the structural weakness and operation impracticality of this arrangement. Moreover, the exposed power generator not only negatively impacts the aesthetic outlook of the unit but also renders the unit vulnerable to surrounding hazards, such as dust, mud, or water.
Therefore, there remains a need for a self-sustaining, structurally reliable, and aesthetically appealing brake light system particularly suitable for employment on a human powered vehicle.
One object of the instant disclosure is to provide a self sustaining brake light system. The brake light system in accordance with the instant disclosure is particularly suitable for employment on a pedal-driven vehicle having a frame and at least two wheels. The brake light system comprises a brake arm mounted on the frame, a power generating unit mounted on the brake arm, and a brake light unit powered by the power generating unit. Particularly, the power generating unit includes a rolling member for establishing frictional contact with the wheel. The power generating unit is adjustably mounted on the brake arm in a pivotable manner. The brake light unit includes at least one lighting module, and is preferably arranged integrally on the brake arm in a conformal fashion.
Another object of the instant disclosure is to provide a brake light system suitable for adapting on an arm portion of a bicycle brake system. The brake light system in accordance with the instant disclosure comprises a mounting mechanism for secure adaptation to the arm portion of the brake system, a power generating unit mounted on the mounting mechanism including a rolling member for establishing frictional contact with a wheel of the bicycle, and a brake light unit powered by the power generating unit. Particularly, the power generating unit is adjustably mounted on the mounting mechanism in a pivotable manner. The brake light unit includes at least one lighting module, and is preferably arranged integrally on the arm portion of the brake system in a conformal fashion.
In order to further the understanding regarding the present invention, the following embodiments are provided along with illustrations to facilitate the disclosure of the present invention.
The aforementioned illustrations and following detailed descriptions are exemplary for the purpose of further explaining the scope of the present invention. Other objectives and advantages related to the present invention will be illustrated in the subsequent descriptions and appended drawings.
Please refer to
Each brake arm 1a/1b is pivotally mounted on the bicycle frame F by a pivot bolt 11a/11b, respectively. A brake cable 12 (such as Bowden cable) is provided to transmit force from a brake lever exerted by the operator of the vehicle. The bent rigid housing of the brake cable 12 (known as “noodle”) is securely secured to an arm link 13 attached to one of the brake arms 1a, while the inner cable of the brake cable is anchored to the other brake arm 1b. A flexible bellows 14 known as the “boot” is provided to cover the exposed inner cable. A pair of Brake shoes 15a, 15b is respectively arranged on the brake arms 1a, 1b in alignment with the proper portions of the wheel W. It is worth noting that, although the instant brake light system is shown to be employed on the direct-pull cantilever brake, a person skilled in the art would recognized that, the instant disclosure would be equally suitable for adaptation on other types of brake designs, given that the subject brake system utilize brake arms of sufficient length and clearance. For one thing, the instant brake system may be suitable for being adapted on an arm portion of a caliper type brake system.
The instant brake light system comprises a power generating unit 2 mounted on the brake arm 1a of a bicycle brake system and a light unit 4 powered by the power generating unit 2. The power generating unit 2 includes a rolling member 21 that can establish frictional contact with the bicycle wheel W through the actuation of the brake arm 1a to harness kinetic energy of the spinning bicycle wheel, thereby powering the light unit 4. Particularly, the rolling member 21 of the power generating unit 2 is arranged with sufficient clearance from the wheel of the bicycle when the brake system is not engaged. As the brake arms 1a, 1b move toward the rim of the bicycle wheel as a result of the actuation of the brake system, the rolling member 21 of the power generating unit 2 mounted thereon (and thus movable there-with) establishes frictional contact with a portion of the bicycle wheel W (such as the sidewall of the wheel). Therefore, when the brake system is activated in the process of decelerating a moving vehicle, friction between the sidewall of the spinning wheel W and rolling member 21 will drive the power generating unit 2 to generate electrical current, which in turn powers the light unit 4. The power generating unit 2 thus serves as both a power source and an actuator for the light unit 4. Moreover, the instant brake system may include a voltage regulating device to protect the system from power surge and thereby increasing operational reliability. In addition, the brake system may utilize an electric charge storage device, such as a capacitor, to prolong the lighting effect of the light unit 4 upon the complete stopping of the bicycle wheel.
Please refer to
The light unit 4 preferably employs energy efficient lighting elements that possess small physical signatures. Semiconductor light source such as light-emitting diode (LED) is a suitable choice for its energy efficiency, light weight, and small physical profile. Particularly, the instant embodiment utilizes a plurality of LED elements in the brake light modules 41a, 41b to increase visibility and create a uniform visual effect. The color of the light unit 4 is preferably red, conforming to the customary color for vehicle brake lights.
The power generating unit 2 is mounted on the brake arm 1a by a mounting mechanism 3. The mounting mechanism 3 comprises a mounting member 31 that is securely disposed on the brake arm 1a and a tensioning member 32 that provides tension to the power generating unit 2. Preferably, the mounting member 31 is designed to provide a firm yet non-rigid coupling of the power generating unit 2 to the brake arm 1a. The tensioning member 32 is arranged to bias the rolling member 21 of the power generating unit 2 toward the contact surface of the bicycle wheel. The firm but non-rigid setup facilitates the establishment of constant and continuous contact between the rolling member 21 and the bicycle wheel without interfering with inward movements of the brake arms during the operation of the brake system. Moreover, the tensioning member 32 of the mounting mechanism 3 can offer structural flexibility to cope with sudden shocks and instantaneous deformations that a wheel may encounter during the travel of the vehicle. For one thing, the instant embodiment utilizes a mounting mechanism that enables pivotally mounting of the power generating unit 2 onto the brake arm 1a. Constant and continuous contact with the bicycle wheel facilitates smooth rotation of the rolling member 21 thereby improving the efficiency of energy conversion. The energy conversion efficiency from the spinning bicycle wheel to the power generating unit 2 may be further enhanced through careful design of the shape of the rolling member 21. A particular example is shown in
The tensioning member 32 may include an elastic component correspondingly arranged in cooperation with the mounting member 31 to provide biasing force to the housing of the power generating unit 2. The tensioning member 32 of the instant embodiment utilizes a coil spring as the elastic component. However, the choice of the elastic component should not be limited to the particular example provided herein. For example, other types of springs, such as V-springs or leaf springs, or even rubber/polyurethane bushings of proper elasticity may be suitable choices for the tensioning member 32, depending on specific design arrangements and/or particular operational requirements.
The mounting mechanism 3 may further include a sub-trim unit 33 for adjusting the position of the power generating unit 2 with respect to the bicycle wheel. Please refer to
A generator cover 23 is provided to protect the power generating unit 2 from surrounding hazards, such as water, dust, or mud. Specifically, the instant exemplary embodiment employs a conformal cover unit that blends in nicely with the contour of the brake arm and provides shielding for the power generating unit 2, revealing the rolling member 21 thereof for establishing frictional contact with the bicycle wheel.
As illustrated by the instant figures, the instant embodiment employs a single power generating unit 2 on one of the brake arms (1a) in an asymmetrical fashion. A cable 24 is utilized to conduct electrical power to the brake light module 41b of the light unit 4 on the opposing brake arm (1b). Specifically, the cable 24 is arranged across the brake arms 1a, 1b along the brake cable 12. Portions of the cable 24 coil around the brake cable 12 before being received by the flexible bellows 14. The arrangement provides the cable 24 enough slack to cope with the actuating movement of the brake arms. By using a single power generating unit 2 to power more than one brake light module, the asymmetrical design of the instant embodiment stresses the advantage of cost effectiveness over the structural concerns of cable wiring complexity. One the other hand, an alternative design may employ a pair of smaller and less powerful dynamo units, with each unit respectively arranged on each brake arm to power a brake light module. This setup gets rid of the need for the power cable 24 running across the brake arms, thereby reducing potential reliability issues resulting from cable breakage. Furthermore, if cost is of primary concern, the instant brake light system may adapt only one dynamo unit and one lighting module on a single brake arm to further simplify structural complexity at the possible cost of visibility and aesthetics.
Finally, please refer to
While the invention has been disclosed with respect to a limited number of embodiments, numerous modifications and variations will be appreciated by those skilled in the art. It is intended, therefore, that the following claims cover all such modifications and variations that may fall within the true spirit and scope of the invention.