公开(公告)号：US20220128082A1

公开(公告)日：2022-04-28

申请号：US17430625

申请日：2020-02-03

Applicant: TOPURA CO., LTD.

Inventor： Shigeto MORI ,  Mayumi MATSUNO ,  Naoki HORIUCHI

IPC: F16B33/02

Abstract: To provide a screw thread which achieves a further reduction in screwing torque while securing removability of a coating film or the like and which is capable of stabilizing conductivity. In a screw thread in which a recessed portion (7) is partially provided on a flank surface (131) of a screw thread ridge provided on a screw thread shaft main body (5), a screw thread ridge (13) in a section where the recessed portion (7) is formed is smaller than a regular screw thread ridge (3), and a ridge height (H12) in a distal end portion in a screwing direction is lower than a ridge height (H11) in a rear end portion in the screwing direction W.

公开(公告)号：US20210254652A1

公开(公告)日：2021-08-19

申请号：US17251595

申请日：2019-06-12

Applicant: TOPURA CO., LTD.

Inventor： Naoki HORIUCHI ,  Keisuke HIBINO

IPC: F16B33/02 ,  F16B35/04

Abstract: An external thread member capable of preventing oblique entry or insertion by a short screw tip shape is provided including, in its shank portion (20), a normal thread area (22), a guide thread area (24) provided at a tip side of the shank portion with respect to the normal thread area (22) and in which a guide screw thread (23) is formed, and a rising area (26) in which a transition screw thread (25) gradually rising from the guide screw thread (23) to the complete screw thread (21) is formed. A tapered guide portion (30) is provided at a tip end side of the normal thread area (22) and includes at least the guide thread area (24). The guide screw thread (23) is formed on an outer periphery of the tapered guide portion (30) which has a maximum diameter equal to or smaller than an inner diameter of an internal thread.

公开(公告)号：US20210231157A1

公开(公告)日：2021-07-29

申请号：US17160151

申请日：2021-01-27

Applicant: TOPURA CO., LTD.

Inventor： Minoru SUGIYAMA ,  Shigeto MORI ,  Mayumi MATSUNO ,  Naoki HORIUCHI

IPC: F16B25/00

Abstract: An external screw member includes a parallel screw portion and a tapered screw portion provided on a side further toward a tip end than the parallel screw portion, and a plurality of sets of step portion and a transition screw thread portion are provided on at least one of the parallel screw portion and the tapered screw portion, the step portion having a reduced thread height in a radial direction and the transition screw thread portion gradually increasing in diameter from the step portion in an anti-driving rotation direction so as to reach a thread height of a normal screw thread portion. A top portion of the transition screw thread portion is positioned at an offset toward a pressure side relative to a position of a regular screw pitch in a minimum diameter portion of the step portion, and transitions to the regular screw pitch in the anti-driving rotation direction.

公开(公告)号：US20190316230A1

公开(公告)日：2019-10-17

申请号：US15999785

申请日：2017-02-16

Applicant: NHK SPRING CO., LTD. ,  TOPURA CO., LTD.

Inventor： Noriyoshi KANEDA ,  Takeshi SUZUKI ,  Kouhei MIYAMOTO ,  Naoki HORIUCHI

IPC: C22C21/02 ,  C22F1/043 ,  C22C21/14 ,  C22C21/16 ,  C22C21/18 ,  C22C21/00 ,  C22F1/057

Abstract: An aluminum alloy contains 0.7% to 1.8% of silicon, 0.5% to 2.1% of copper, 0.4% to 1.8% of manganese, 0.6% to 1.6% of magnesium, and 0.1% to 0.7% of zinc in terms of mass ratio and the balance aluminum with inevitable impurities.