Title:
自穿孔ねじの転造ダイス
Document Type and Number:
Japanese Patent JP6894592
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a rolling die for a self-drilling screw which can smoothly perform screwing-in and can effectively prevent crack occurrence in a woody member.SOLUTION: A die 11 for rolling a self-drilling screw in which on a portion provided with a thread of a shank having a sharp tip at one end and a head at the other end, a cut groove having a depth reaching a valley part of the thread is so formed as to divide the thread. In this die, a groove molding part 14 for the cut groove is provided at a position on a rear end side of a thread processed face 12 in a stationery die 11a, and this groove molding part 14 is formed from: a groove processing part 15 which is located along a rolling direction of a screw material; and a relief groove 16 which is located at a position on a head 4 side of the screw material in parallel to the groove processing part 15, and is reentrant in a groove processed face 15a of the groove processing part 15.SELECTED DRAWING: Figure 2
Inventors:
Takemasa Wakai
Application Number:
JP2017117635A
Publication Date:
June 30, 2021
Filing Date:
June 15, 2017
Export Citation:
Assignee:
Wakai Holdings Co., Ltd.
International Classes:
B21H3/10; F16B25/02
Domestic Patent References:
| JP2017067190A | ||||
| JP1143646U | ||||
| JP2004344952A | ||||
| JP2280935A |
Foreign References:
| KR1020090015444A |