Patent ID: 11938559
Assignee: YAMAZAKI MAZAK CORPORATION
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 9:
10. A machine tool comprising:
a friction stir welding tool;
a workpiece support member configured to support a workpiece;
a tool support member supporting the friction stir welding tool;
a first driver configured to move the tool support member relative to the workpiece support member;
a second driver configured to rotate a stir pin;
a controller configured to control the first driver and the second driver; and
the friction stir welding tool comprising:
a shoulder member having a shoulder surface configured to press a workpiece;
a pin holder; and
a stir pin provided in the shoulder member rotatable about a first axis with respect to the shoulder member, the stir pin comprising:
a base end portion configured to be held in the pin holder to be rotatable about the first axis, the base end portion having a maximum outer diameter at an outermost edge about the first axis;
a stirring portion provided to project from the shoulder member to be rotatable with respect to the shoulder member about the first axis together with the base end portion; and
an intermediate portion comprising:
a second portion connected to the stirring portion to be rotatable about the first axis together with the stirring portion and having a second diameter passing through the first axis; and
a first portion provided between and connected to the base end portion and the second portion to be rotatable about the first axis together with the base end portion and the second portion, the first portion having an end surface to which the second portion is connected coaxially with the first portion and which has a maximum diameter passing through the first axis larger than the second diameter, the end surface having a ring-shaped receiving surface configured to receive a material waste generated when the stirring portion performs a friction stirring, the ring-shaped receiving surface having a maximum outer diameter at an outermost edge about the first axis that is equal to or greater than the maximum outer diameter of the base end portion,

wherein the shoulder member has
a first through hole which is provided at a leading end portion of the shoulder member and through which the stir pin projects from the leading end portion, and
a second through hole through which the material waste in the shoulder member is discharged to an outside of the shoulder member, and

wherein the second through hole is provided at least partly radially outward from the second portion along the first axis.