Umbrella frame

Abstract

An umbrella frame has a main shaft and multiple branches pivotally attached around the main shaft. The main shaft has an immovable upper base and a movable lower base each having multiple retaining slots. Each branch is divided into a front section, a middle section and a rear section and has a supporting rib and a pulling rib both pivotally attached under the front section. The front sections and the supporting ribs have pin heads to respectively engage the retaining slots on the upper and lower bases so that the branches are pivotally attached to the main shaft. Moreover, the supporting rib, the pulling ribs, the front section and middle section perform a quaternary-linkage to make operation conveniently and stably. Additionally, the umbrella frame is made of high-stiffness plastic so that the umbrella frame does not rust and has excellent anti-deforming efficiency.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an umbrella frame, and more particularly to an umbrella frame that is made of high-stiffness plastic to substitute conventional metal rivets, modified in structure to make umbrella frame stable without deformation and enables to change different actuating modules. [0003]2. Description of Related Art [0004] Conventional umbrella frames are made of metal material, wherein pivotal joints on the umbrella frames are secured by copper rivets. Particularly, multiple ribs are radially attached around a main shaft by a metal wire penetrating all ribs and pivoted on the metal wire. Attaching the ribs by the metal wire is time-consuming in manufacturing procedures and the pivotal joints and the ribs are rusted, cracked or broken easily so that the umbrella frequently has malfunction problems when extends or contracts. Moreover, the umbrella frame may be deformed or bent when an umbrella canopy ...

AI Technical Summary

Benefits of technology

"The present invention provides an improved umbrella frame that has several technical effects. Firstly, the frame is simplified and made of stiffness material to eliminate the conventional metal wire and make assembly and disassembly quick without using auxiliary machines. Secondly, the frame has multiple corresponding retaining slots and pivotally engaged branches, making it easy to assemble and disassemble. Thirdly, the frame has various pressing devices with humanity-oriented design to make operation convenient. Fourthly, the frame has plastic joints to eliminate the conventional copper rivets and avoid rust problem. Fifthly, the frame has a retractable sheet with a main shaft and multiple supporting ribs pivotally connected between the lower base and the branches, making the frame durable and resistant to deformation. Overall, the frame is stable, quick, and convenient to operate, and has excellent resistance to deformation."

Problems solved by technology

Attaching the ribs by the metal wire is time-consuming in manufacturing procedures and the pivotal joints and the ribs are rusted, cracked or broken easily so that the umbrella frequently has malfunction problems when extends or contracts.

Moreover, the umbrella frame may be deformed or bent when an umbrella canopy on the umbrella frame resists strong wind because the ribs are thin and do not have excellent stiffness.

Although manufacturing technic of the umbrella is improved to decrease the malfunction frequency, fundamental problems on structure and material are not resolved.

Some improved conventional umbrella frames are made of fiber reinforced plastic (FRP) that enhances the anti-rust efficiency of the umbrella frame, however, structure design is still incomplete in efficiently improving stiffness, assembling convenience and modular change of activating devices.

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