1. Field of the Invention
The present invention relates to umbrellas and more particularly to an FRP (fiber glass reinforced plastics) umbrella frame with characteristics such as enhanced strength, quick assembly, and reduced size after folded.
2. Description of Related Art
Umbrella frame designs take many different forms. A conventional umbrella having a two-section rib is shown in FIG. 9. Such umbrella frame has a number of disadvantages as observed by the present inventor. For example, a rivet is used in each of five pivot joints P1 to P5. However, it is known that riveting is a tedious task. Also, uniform quality of riveting on the pivot joints P1 to P5 for each frame element is not easy to control. Typically, there are about total 30 to 40 pivot mechanisms in an umbrella frame. Unfortunately, one defective pivot mechanism will make the whole umbrella unusable after a short period of time due to rust in the pivot mechanisms. Further, stress tends to concentrate on the pivot mechanisms. As a result, the frame is susceptible of break in folding or expanding the umbrella.
An FRP umbrella for solving the problem of rust in the pivot mechanisms caused by riveting is proposed. However, the FRP umbrella still suffered from several disadvantages. For example, ribs of the FRP umbrella frame are shaped as cylinders for providing a sufficient support to the frame. Also, a variety of plastic molded connecting elements and pivot elements are fitted at two ends and in intermediate section of the cylindrical rib, respectively. As such, each frame element is increased in size, resulting in a bulky FRP frame. This can cause difficulties in storage, packing, and delivery of the umbrella. Hence, a commercialized FRP umbrella is still not available after such technique has been developed for more than 20 years. Thus, continuing improvements in the FRP umbrella frame are constantly being sought.
It is an object of the present invention to provide an FRP umbrella frame having advantages such as enhanced strength, quick assembly, and much reduced size after folded.
It is another object of the present invention to provide a lightweight FRP umbrella frame for facilitating storage, packing, and delivery.
It is a further object of the present invention to provide an enhanced FRP umbrella frame for prolonging a useful life.
The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.