1. Field of the Invention
The present invention relates to a screw having a threaded shank and being adapted to attach two sheets of material together, and particularly to a captive screw which can securely and firmly combine the sheets together.
2. Prior Art
Various conventional fasteners are utilized to attach two sheets of material together. The sheets may for example be the side plate or a bottom plate of an electronic device, and a printed circuit board (PCB). In another example, the sheets may be a pair of overlapping metal roof sheets or a pair of overlapping siding panels, which are normally fastened in place by conventional fasteners such as screws. Referring to
Thus, an improved captive screw which solves the above-mentioned problems is strongly desired.
Accordingly, an object of the present invention is to provide a screw with a cap which securely and firmly combines two sheets together.
To achieve the above-mentioned object, a captive screw in accordance with the present invention is provided for attaching two sheets together. The captive screw includes a screw and a cap. The screw includes a head, a threaded shank, and a flange located between the head and the shank. The cap includes a cavity and a skirt portion. The shank forms a plurality of ribs on an underside thereof. The flange forms a plurality of vertical ridges therearound. The cap and the screw are combined, with the head and the flange tightly fitted in the cavity. The shank extends out of the skirt portion, with a cylindrical space defined therebetween. A rod portion of a complementary engaging rivet can then be received in the space.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of a preferred embodiment of the present invention with attached drawings, in which:
Referring to
The screw 40 comprises a head 41, a threaded shank 43, and a flange 42 connecting between the head 41 and the shank 43. The flange 42 is generally cylindrical. A diameter of the flange 42 is greater than that of the shank 43. A plurality of closely spaced, vertical slim ridges 44 is formed around an outer circumferential surface of the flange 42. A topmost portion of the head 41 defines a generally hexagonal recess 45 therein, which is adapted to engagingly receive a driving tool (not shown).
Referring also to
The first sheet 10 defines through hole 11 therein. The second sheet 20 defines a slot 21 therein corresponding to the through hole 11. A rivet 30 is riveted in the slot 21. The rivet 30 comprises a rod portion 32 defining a threaded hole 31 therein. In use of the captive screw 80, the first sheet 10 is placed on the second sheet 20, with the rod portion 32 protruding out from the through hole 11 of the first sheet 10. Then, the captive screw 80 is engaged with the free end of the rivet 30. The threaded shank 43 is fitted in the through hole 31 of the rivet 30, with the free end of the rod portion 32 of the rivet 30 being received in said cylindrical space of the cap 50. When the captive screw 80 is fully threaded onto the rivet 30, the ribs 52 of the skirt portion 53 interferentially engage against a top surface of the first sheet 10 (as shown in
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Number | Date | Country | Kind |
---|---|---|---|
92216118 | Sep 2003 | TW | national |