Tube expanding method and apparatus of damper tube
AssigneeShowa Corporation
InventorsKenichi SHIMAI, Toshio OGURA
Life of this patent
Estimating the term…
Abstract
In a tube expanding apparatus of a damper tube supporting a thrust force of a punch applied to the damper tube by a stopper at a time of retaining one end of the damper tube by the stopper, inserting the other end of the damper tube to a die, inserting the punch to the other end of the damper tube so as to propel, and expand the other end of the damper tube while carrying out an ironing operation, the apparatus is provided with a stopper releasing means for releasing the stopper at a time when a load in an axial direction applied to the damper tube due to an elongation by the ironing work of the damper tube increases over a critical load which is previously determined to be a smaller load than an expected buckling load in the damper tube.
Claims5
A tube expanding method for a damper tube, comprising the steps of supporting a thrust force of a punch applied to the damper tube by a stopper while retaining one end of the damper tube by the stopper, inserting an other end of the damper tube to a die, inserting the punch to the other end of the damper tube so as to propel, and expand the other end of said damper tube while carrying out an ironing operation;
- and releasing the stopper when a load in an axial direction applied to said damper tube due to an elongation by the ironing operation of the damper tube increases over a critical load which is previously determined to be a smaller load than an expected buckling load in the damper tube.
A tube expanding apparatus of a damper tube supporting a thrust force of a punch applied to the damper tube by a stopper while retaining one end of the damper tube by the stopper, inserting an other end of the damper tube to a die, inserting the punch to the other end of the damper tube so as to propel, and expand the other end of said damper tube while carrying out an ironing operation, wherein the apparatus is provided with a stopper releasing means for releasing the stopper when a load in an axial direction applied to said damper tube due to an elongation by the ironing operation of the damper tube increases over a critical load which is previously determined to be a smaller load than an expected buckling load in the damper tube.
Dependencies are inferred from the claim text.