| 摘要 |
An electric current carrying device such as an electric light bulb releasably receivable in a socket in which the device comprises a mounting base with an electrically conducting peripheral wall which may be of metal, an inner electrically conducting wall which may also be of metal in the socket for receiving the base in electrical contact, a helical screw thread on either the base or the socket wall and a plurality of circumferentially spaced spring tabs on the other wall. Each tab has a plurality of ridges spaced from each other in a direction parallel to the axis of the base or socket with each ridge lying along a section of a helix of substantially the same pitch and dimensions as those of the screw thread for engaging in the screw thread and retaining the base in the socket in its innermost position. The spring tabs are elongated and each has one edge that is parallel to the axis fixed to its wall as by being integral therewith and an opposite edge free in a cantilever construction and spaced from its wall with the result that when the base is inserted in the socket the tabs are compressed toward their wall to exert a holding spring action serving to retain the base in the socket and the helical section ridges on the tabs engage the screw thread at a plurality of circumferentially spaced areas not only to securely retain the base in the socket but also to provide good electrical contact between the walls and, as in the case of a light bulb, between the end contact members on the base and socket. |
