| 摘要 |
The present invention relates to a tapping screw to be coupled by machining a female screw and, more specifically, to a general-purpose tapping screw which can be used for all injection-molded objects such as synthetic resin or the like, flexible metal and hard metal. The present invention provides a general use tapping screw, which is a two-line screw having a cylindrical body, and main threads and auxiliary threads which are formed on the outer circumferential surface of the body, wherein the outer diameter of the auxiliary threads is 92ˆ¼97% the outer diameter of the main threads, the angle of the front flank surfaces of the main threads and the auxiliary threads is in the range of 12±3 degrees, the angle of the rear flank surfaces of the main threads is in the range of 25±3 degrees, the angle of the rear flank surfaces of the auxiliary threads is in the range of 20±3 degrees, and intervals between a first pitch from the main thread to the auxiliary thread and a second pitch from the auxiliary thread to the next main threads have a difference in the range of ±10-20%. The present invention also provides a coupling method using the same. |
