EXPANDABLE COLUMN POSITIONING MECHANISM

摘要

The expandable column positioning mechanism of the present invention was developed to improve the reliability of the operation thereof by reducing the number of components without the need for movable elements. An expandable column is accommodated in a fixed frame so as to freely axially extend therefrom and retract thereinto. The expandable column has a plurality of holes longitudinally spaced therein. An actuating piece extends from an end of the fixed frame. The actuating piece has resiliency or elasticity and is pivotally mounted on the fixed frame about a connecting portion thereof. The actuating piece has a pin extending therefrom for engaging the holes of the extendable column. The expandable column is positioned by the engagement of one of the holes with the pin. The hole and the pin are disengaged by pivoting the actuating piece away from the expandable column, so that the expandable column can be extended or retracted.