Abstract: This invention relates to umbrellas in general. In particular it relates to umbrellas which automatically open and close. This automatic opening and closing of the umbrella in the presented embodiments is accomplished by means of the rotation of a threaded rod. A key improvement disclosed herein includes a simplification both in the construction of the umbrella itself and in the means for conveniently converting the umbrella to the ordinary manually opened and closed umbrella should the necessity occur. It has been discovered by experimentation that parts previously included in the assembly of prior art are unexpectedly not necessary with the proper choice of design.