公开(公告)号：US20210270154A1

公开(公告)日：2021-09-02

申请号：US17317773

申请日：2021-05-11

申请人： NITTAN VALVE CO., LTD.

发明人： Koji KUNITAKE ,  Daiki SATO ,  Yuki SASAGAWA

IPC分类号： F01L3/20 ,  B21K1/22

摘要： A method for manufacturing an engine poppet valve may comprise a forging operation, a diameter-decreasing operation, and a joining operation. At the forging operation, an intermediate member at which a valve head portion and an intermediate stem portion are made integral by way of a neck portion may be formed. At the diameter-decreasing operation, the intermediate stem portion may be inserted between/among a plurality of diameter-decreasing tools that have stem member compressing surfaces and stem member inlet surfaces formed so as to be progressively distant from the stem member compressing surfaces and toward the tip end and that are arranged at a plurality of circumferentially equipartite locations about a circumference of the intermediate stem portion, application at the intermediate stem portion from a base end portion of compressive forces which are inwardly directed in a radial direction from the compressing surfaces of the respective diameter-decreasing tools which have been made to come in contact with a part of the intermediate stem portion that has been made to rotate while being displaced in relative fashion in a direction along a central axis thereof causing the part of the intermediate stem portion to be decreased in diameter from the base end portion and causing a main body portion of a first stem portion to be formed at the intermediate member and also causing formation by the compressing surfaces of a stepped portion which is continuous with the main body portion, and formation, by an absence of decrease in diameter of a remaining portion at the intermediate stem portion, of a second stem portion which is broader in girth than the main body portion and which is continuous with the neck portion and which is also continuous with the main body portion by way of the stepped portion. At the joining operation, a stem end member having a same outside diameter as the main body portion may be joined to a base end portion of the main body portion.

公开(公告)号：US20180264530A1

公开(公告)日：2018-09-20

申请号：US15542607

申请日：2015-05-15

申请人： NITTAN VALVE CO., LTD.

发明人： Koichi HOMMA ,  Masaaki NIIRO ,  Daiki SATO

IPC分类号： B21C23/21 ,  F01L3/14 ,  F01L3/24 ,  B21C31/00

CPC分类号： B21C23/215 ,  B21C23/211 ,  B21C31/00 ,  B23P15/002 ,  F01L3/14 ,  F01L3/24 ,  F01L2103/01

摘要： Each time a highly-viscous substance is extruded, a variation in weight of each cut piece of the highly-viscous substance is minimized. Metallic sodium (5) loaded in an extruder main body (3) is extruded from a nozzle (7) of the extruder main body (3) with a pressing tool (4) and, when it is detected that the metallic sodium (5) is extruded to a predetermined position, the movement of the pressing tool (4) is stopped and the extruded metallic sodium (5) is cut. In this case, an impulse (P) after stop is brought closer to a constant value until a load no longer acts on the metallic sodium (5) in the extruder main body (3) after stopping the movement of the pressing tool (4) by adjusting the movement speed of the pressing tool (4).