Methods and apparatus for expelling a projectile

Abstract

Some embodiments are directed to a tool arranged to at least partially expel a projectile. The tool includes a housing having a primary axis, and, at least partially enclosed within the housing, a firing mechanism and a projectile arranged to be at least partially expelled from the housing in a direction parallel to the primary axis on actuation of the firing mechanism. The firing mechanism includes a chemical propellant and at least two moveable components, both of the components being moveable in a direction parallel to the primary axis within the housing. The chemical propellant is arranged such that, when activated, the gases created thereby act to expel the projectile, and the moveable components are arranged such that displacement of both components from a rest position is required to activate the propellant, and the components are moveable in response to a force applied directly along the primary axis.

Dependencies are inferred from the claim text.