| 摘要 |
PROBLEM TO BE SOLVED: To provide a chamfering device for the back face of a pipe hole capable of completing the back face chamfering work by one process by being continuously inserted into the pipe hole. SOLUTION: This chamfering device for the back-face of a pipe hole has a pair of back face chamfering cutters 20 extended in parallel along a longitudinal axis of a cylindrical housing 10 opened at its one end, rockably on an intermediate fulcrum shaft, and the back face chamfering cutters have chamfering blades 2 respectively near a lower opening of the cylindrical housing, and enlarged parts 23 outwardly projecting in the directions opposite to each other at the end part opposite to the chamfering blades. The chamfering device comprises elastic means 24 for energizing the cutters in the direction to reduce an outer diameter of a pair of chamfering blades at all times, are mounted on side edge parts opposite to the chamfering blades, of the back face chamfering cutters, and sliding operating members 30 slidably mounted in the cylindrical housing, respectively abutted on the enlarged parts of the back face chamfering cutters, and enlarging the chamfering blade at an opposite side by rocking the back face chamfering cutters to allow the enlarged parts to be close to each other.
|
