Patent Application
20110240423
1. Field of the Invention
The present invention relates to a brake block for bicycle, and more particularly, to a brake block which has a fixing portion made of plastic and a pad body made of rubber.
2. Description of Related Art
Cycling has become an extremely popular recreational activity throughout the world in recent decades. As more and more people indulge themselves in cycling, a demand for innovation and improvement of bicycles and bicycle parts has arisen.
A conventional brake block for bicycle is shown in
However, the conventional brake block has the following drawbacks: first of all, the conventional brake block is integrally made of rubber by press molding. A tolerance range in size of the conventional brake block made by press molding is generally between +/−0.3. This huge tolerance range in size makes it difficult for the brake block to fittedly assemble with the holder 5, such that the brake block may easily detach from the holder 5. Furthermore, due to a deformable texture of rubber, the brake block is easily deformed when it is frictionally contacted with the wheel rim when operating, such that a frictional effect of the braking surface 41 is reduced. In addition, when the brake block is gradually and entirely worn, the holder 5 is exposed, and directly contacts with the wheel rim, thereby the holder is easily damaged.
The present invention has arisen to obviate/mitigate the disadvantages of the conventional brake block for bicycle.
The main objective of the present invention is to provide an improved brake block for bicycle.
To achieve the objective, the brake block for bicycle in accordance with the present invention comprises a base which is made by plastic injection molding and a pad body made of rubber. The base has a fixing portion formed on one side thereof and a connecting portion formed on an opposite side thereof. The fixing portion has a slot circumferentially defined in an outer periphery thereof for slidably engaging with a holder of a bicycle brake shoe. The connecting portion includes at least one neck connecting with the fixing portion and a connecting plate which is mounted on the at least one neck. In one aspect of the present invention, the connecting portion includes a plurality of necks connecting with the fixing portion. A gap is defined in every two adjacent necks. The connecting plate has a high coefficient of friction, such that a friction sound bursts when the connecting plate is frictionally contacted. The pad body has one side integrally covering the connecting plate and is partially fillingly received in the gaps defined in every two adjacent necks of the connecting portion of the base; such that the base and the pad body formed an integral part. An opposite side of the pad body has a braking portion formed thereon for providing a frictional effect. The base and the pad body have different colors. The color of the base is contrasting with that of the pad body for indicating wear of the pad body.
The present invention will become more obvious 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.
Referring to the drawings and initially to
Further referring to
In view of the above descriptions, the brake block in accordance with the present invention has the following advantages: first of all, the base 1 is made by plastic injection molding, such that a tolerance range in size can be reduced to +/−0.05 which is relatively small compares to that of the brake block in accordance with the prior art which is entirely made of rubber by press molding. Therefore, the base 1 can be fittedly assembled with the holder 3 to prevent coming off of the base 1 from the holder 3. Secondly, due to a harder texture of plastic compares to that of rubber, the base 1 is not deformable when being compressed; hence the base 1 rigidly supports the pad body 2 to enhance the frictional effect of the braking portion 20 of the pad body 2 to the wheel rim. Such that the braking portion 20 tightly abuts against the wheel rim to consistently provide a frictional effect in operating state, and the braking portion 20 is not deformed easily with the support from the base 1.
In addition, the color of the base 1 contrasts with that of the pad body 2. By the contrasting colors of the base 1 and the pad body 2, a user can easily identify the wear of the pad body 2, which allows the user to immediately and instantly replace the brake block when the pad body 2 is worn. Furthermore, the connecting plate 112 of the base 1 bursts a friction sound when it is frictionally contacted due to the high coefficient of friction of the connecting plate 112 of the connecting portion 11, such that the user is immediately alerted the wear of the pad body 2 by the friction sound. The connecting plate 112 of the connecting portion 11 also protects the holder 3 from frictionally contacting with the wheel rim when the pad body 2 is worn. Thereby, a usage life of the holder 3 is prolonged.
Although the invention has been explained in relations to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.
