BACKGROUND OF THE INVENTION
 This invention relates to a parasol, particularly to one convenient to have its parasol gores cut and together sewed into a parasol cover, facilitating producing and having an aesthetic appearance.
 The structure of a conventional parasol, as shown in FIG. 1, includes a parasol shaft 10 having a plurality of parasol ribs 30 provided radially on top. A number of stretchers 40 are respectively connected at one end pivotally with the intermediate portion of each parasol rib 30, and at the other end connected with a sliding sleeve 401 fitted around the parasol shaft 10. Then, a parasol cover 20 made of a number of parasol gores is fixed on the top of the parasol ribs 30. Thus, when the sliding sleeve 401 is pushed upward, the stretchers 40 are synchronously stretched outward to make the parasol ribs 30 and the parasol cover 20 spread outward together, as shown in FIG. 1. Besides, a number of suspending lower portions 201 of the parasol cover 20 protruding out of the ends of the parasol ribs 30 are preset around the circumferential edge of the parasol cover 20 in order to acquire a comparatively good effect of blocking off sunlight, because the suspending lower portions 201 will drop down to act as a sunshade when the parasol cover 20 is spread outward.
 However, such a design of the suspending lower portions 201 cause much trouble in the process of making a conventional parasol. As the parasol ribs 30 are shaped straight, an extra length of each parasol gore exceeding the length of the parasol rib 30 has to be preset when the parasol gore is cut in shape so as to make up a suspending lower portions 201 around the circumferential edge of the parasol cover 20. Then, these parasol gores are sewed together to make up an integral parasol cover 20. The drawback of such a design is that a sewed joint between every two neighboring suspending lower portions 201 may be creased and spoil an integral aesthetic appearance in case the abutting sides of every two parasol gores are sewed together closely and tightly.
 To solve such a problem, each suspending lower portion 201 has its opposite sides cut in an arcuate shape, as shown in FIGS. 1 and 2, letting the width of each suspending lower portion 201 becomes somewhat smaller than that between the outermost ends of two parasol ribs 30 stretched outward. Thus, after the parasol gores are sewed into a parasol cover 20, with the abutting suspending edges 201 not yet sewed together, the parasol cover 20 is formed to have an inverted U-shaped recess 202 at the outermost end of each parasol rib 30, enabling each suspending lower portion 201 between every two neighboring parasol ribs 30 to drop down naturally, causing no crease.
 Nevertheless, the way of cutting the opposite sides of each suspending lower portion 201 in an arcuate shape and sewing them in an inverted U-shaped recess 202 increases difficulty in setting up patterns for parasol gores and cutting them in shape. Further, during sewing, it is necessary to turn over the angles of the parasol gores time after time in order to match with the shape of the inverted U-shaped recesses 202, and at the same time watch if the joint between two neighboring suspending lower portion 201 is neat and smooth, thus increasing more difficulty in sewing.
SUMMART OF THE INVENTION
 The objective of the invention is to offer a parasol convenient to have its parasol gores cut and sewed together into a parasol cover, and having effect of facilitating producing. The parasol of this invention includes a parasol shaft having a plurality of parasol ribs provided radially on top, with the parasol ribs provided on top with a parasol cover made of numerous parasol gores. The feature of the invention is that each parasol rib has a lower curved receiving portion in an outermost end. Thus, when the parasol cover is spread on the parasol ribs, the parasol cover on the lower receiving portions of the parasol ribs will naturally drop down and form a suspending lower portion
BRIEF DESCRIPTION OF DRAWINGS
 This invention will be better understood by referring to the accompanying drawings, wherein:
 FIG. 1 is a perspective view of a conventional parasol:
 FIG. 2 is a partially perspective view of the conventional parasol:
 FIG. 3 is a perspective view of a parasol in the present invention:
 FIG. 4 is a side view of a parasol rib of the parasol in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
 A preferred embodiment of a parasol in the present invention, as shown in FIG. 3, includes a parasol shaft 1 having a plurality of parasol ribs 3 provided radially and movably on top. Each parasol rib 3 is pivotally connected with one end of a stretcher 4 on an intermediate portion, and the stretcher 4 has its other end connected with a sliding sleeve 41 around the parasol shaft 1. The feature of the invention is that each parasol rib 3 has its outermost end curving downward and forming a lower curved receiving portion 31, as shown in FIG. 4.
 By so designing, the parasol cover 2 has its circumferential edge kept in an integral shape and naturally formed into a suspending lower portion 21 curving down along the lower receiving portions 31 of the parasol ribs 3 after it is mounted on the parasol shaft 1 and the parasol ribs 3.
 To sum up, the design for making a parasol in the present invention can not only simplify the process of setting up patterns for parasol gores and cutting them in shape, but also simplify the steps of sewing the parasol gores into a parasol cover 2 and keep the suspending lower portion 21 naturally curving down to serve as a sunshade.
 While the preferred embodiment of the invention has been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications that may fall within the spirit and scope of the invention.