Title:
ROLLING DIE OF DRILL SCREW
Document Type and Number:
Japanese Patent JP2019010665
Kind Code:
A
Abstract:
To provide a rolling die of a drill screw capable of surely removing a forging time burr generated in a drill part provided on the shaft part tip of a screw material simultaneously with a rolling process of a screw thread.SOLUTION: In a die for roling a screw thread 7 in a base shaft part 2 of a screw material 1 formed with a drill part forging time burr 6 on an outer surface of a drill part 4, a first deburring projection 15 and a second deburring projection 16 are provided in a midway position in the rolling direction of the screw material 1 in a lower part of a screw thread processing surface 12 formed in a die 11a, both the deburring projections 15 and 16 are formed so as to become different in vertical width and in projection height of impact adding surfaces 15a and 16a turning to an extension line of the screw thread processing surface, and the burr is removed by adding a gradual impact to the burr 6 formed in the drill part 4.SELECTED DRAWING: Figure 1
Inventors:
WAKAI TAKEMASA
OKAMOTO KAZUYA
NOMURA HITOSHI
OKAMOTO KAZUYA
NOMURA HITOSHI
Application Number:
JP2017129042A
Publication Date:
January 24, 2019
Filing Date:
June 30, 2017
Export Citation:
Assignee:
WAKAI HOLDINGS CO LTD
International Classes:
B21H3/10