Method and apparatus for measuring pneumatic differential drag forces
US4300451A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 12, 1978 |
| Grant date | Nov 17, 1981 |
| Priority date | — |
| Expiry date | Jun 12, 1998 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF42C15/29
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A differential drag apparatus is disclosed for detecting air pressure forces on a drag-sensing body. The body is movable in response to a predetermined magnitude of air pressure force. A pressure regulator responds to the movement of the body by releasing uniform pressure to an activation system. The activation system in turn releases a trigger provided the air pressure force acting against the drag-sensing body remains above the predetermined magnitude for a predetermined length of time. The trigger upon release may perform any number of activates such as opening or closing an electrical circuit, initiating a mechanical response, i.e. releasing a parachute, or detonating a small munition charge. The detonation of a charge, for example, may in turn ignite a rocket motor, release an explosive, or any other of related activities. The apparatus is insensitive to short duration forces above or below the predetermined magnitude, and radiation as results from proximate nuclear blast. The trigger and regulator are initially primed by a pyro-train fuse; yet, activated only by differential movement of the drag-sensing body for a predetermined length of time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.