Push actuator

US4875660A · kind A · utility

Inventors

• Pierre Gagnon · Vaudreuil-Dorion, CA
• Pierre Laforest · Montréal, CA

Key dates

• Filing date: Feb 6, 1989
• Grant date: Oct 24, 1989
• Expiry date: Feb 6, 2009

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B66F7/10
• WIPO field: Handling
• WIPO sector: Mechanical engineering

Abstract

This telescopic tube is formed of a first and of a second continuous bands wound in a spiral and in a helix, respectively, with the turns of each band lying flat against each other in the retracted position of the tube. The turns of the respective bands are normal to one another. To extend the tube, the turns of the first band are spaced from each other, and the turns of the second band are inserted between the spaced turns of the first band, so as to act as spacers for the latter turns. A mechanism is described to cause extension and retraction of the tube which is mainly used as a push actuator.