Automatic opening umbrella mechanisms

An automatic opening umbrella mechanism which provides a new design, by which users can open an umbrella in a quick and accurate manner with enhanced efficiency. The structure primarily contains a spring disposed between the midpoint of a first main umbrella stretcher and the upper end of the umbrella runner. The resilient restoring force of the spring helps opening an umbrella.

BACKGROUND OF THE INVENTION
 Conventional automatic umbrellas use springs seated in the umbrella stick
 to open an umbrella canopy. When the runner escapes from the retention and
 the stick extends, the runner moves upwards and the umbrella stretcher
 system spreads out to complete the opening operation of an umbrella.
 However, these known umbrella structures often malfunction due to the
 limitation of a single spring's insufficient resilient forces and the
 umbrella stretchers' fundamental structure. Users can not open the
 umbrella completely and smoothly. Thus it is desirable to have
 improvements made on conventional opening umbrella mechanisms to eliminate
 these deficiencies.
 In view of the above problems, the present invention is to provide an
 improved opening umbrella mechanism in which a spring is disposed between
 the runner and the first main umbrella stretcher to provide an auxiliary
 pulling force in the opening operation of the umbrella to achieve a smooth
 opening effect. Now the structural features and advantages of the
 invention will be described in detail with reference to the accompanying
 drawings.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
 FIGS. 1 and 2 show an exemplary application of the opening mechanism
 according to the invention used in a quadruple foldable umbrella. The
 opening mechanism comprises an umbrella stretcher system (1), an umbrella
 stick (2), an upper grooved element (3) and a runner (4). These components
 are the same as those of a prior art umbrella and are well known to the
 public. Thus they will not be described in detail here. The invention is
 featured by a spring (5) disposed between the midpoint of a first umbrella
 stretcher (11) and the upper end of the runner (4). When closing the
 umbrella as shown in FIG. 1, the spring (5) is stretched. In an operation
 of opening the umbrella, the runner (4) will escape from the retention and
 move up. Under the resultant resilient forces of the spring in the
 umbrella stick in conjunction with the auxiliary spring (5), the umbrella
 canopy can smoothly stretch out. Thus the opening operation can be more
 quick and accurate.
 FIG. 3 shows an application of the embodiment of an opening mechanism
 according to the invention used in an automatic quadruple foldable
 umbrella. The spring (5) is connected at one end to the upper end of the
 runner (4) and at the other end to the midpoint of a first main umbrella
 stretcher (11). The spring provides an auxiliary force to pull the runner
 (4) to the upper end of the umbrella stick during an opening operation.
 FIG. 4 shown another exemplary application of the opening mechanism
 according to the invention used in an automatic straight umbrella. The
 spring (5) is also disposed between an umbrella stretcher (7) and the
 runner (4) to achieve the same auxiliary effect as the one described
 above.
 From the described above, the invention uses an additional spring to serve
 as an aid to the opening operation of an umbrella. Evidently it can
 achieve the effect set forth at the beginning of the text. Besides it also
 has originality in structure. Thus the invention has the essence of a
 patent. We hereby file an application of granting a patent.