US 11,724,321 B2
Hole drilling machine and method for drilling oval hole and inner-diameter-changing hole by means of hole drilling machine
Munehiro Murakami, Hamamatsu (JP); Toshio Suzuki, Hamamatsu (JP); Taketo Nakamura, Hamamatsu (JP); Kazushige Morozumi, Hamamatsu (JP); Tatsunori Sato, Hamamatsu (JP); Yuya Masuda, Hamamatsu (JP); and Daiki Ishizuka, Hamamatsu (JP)
Assigned to ENSHU LIMITED, Hamamatsu (JP)
Filed by ENSHU Limited, Hamamatsu (JP)
Filed on Sep. 8, 2021, as Appl. No. 17/468,897.
Application 17/468,897 is a division of application No. 16/650,166, granted, now 11,154,939, previously published as PCT/JP2019/026361, filed on Jul. 2, 2019.
Claims priority of application No. 2018-138685 (JP), filed on Jul. 24, 2018.
Prior Publication US 2021/0402491 A1, Dec. 30, 2021
Int. Cl. B23B 41/04 (2006.01); B23B 41/12 (2006.01); B23B 41/06 (2006.01); B23B 35/00 (2006.01)
CPC B23B 41/04 (2013.01) [B23B 41/06 (2013.01); B23B 41/12 (2013.01); B23B 35/00 (2013.01); B23B 2215/245 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A hole drilling machine comprising:
a work table configured to hold a work piece having a lower hole in a through-hole shape;
a spindle formed in a shape of a rod penetrating the lower hole of the work piece held on the work table and configured to spin a processing tool, which holds a cutting blade configured to cut the work piece, about an axis while holding one end portion of the processing tool to turnably displace the cutting blade about the axis and rotatably drive an entirety of the processing tool on a circular path about a center axis at a position eccentric with a center axis of spinning;
an auxiliary spindle having a tool fitting portion in which the other end side of the processing tool is slidably fitted and configured to rotatably drive the tool fitting portion on a circular path parallel with the circular path for the spindle;
a spindle displacement mechanism configured to displace the spindle and the work table relative to each other in a Y-axis direction as an axis direction of the spindle to decrease or increase a distance between the spindle and the work table; and
a control apparatus configured to control actuation of each of the spindle, the auxiliary spindle, and the spindle displacement mechanism,
wherein the control apparatus
turnably displaces the processing tool while displacing the processing tool in the Y-axis direction in a rotatably-driven state, thereby shaping, at the work piece, at least one of an oval hole or an inner-diameter-changing hole of which inner diameter changes along a hole depth direction.