US Patent 7473241 Device and method for injecting

The invention relates to a device for injecting a fluid including a pressure chamber for accommodating the fluid, a piston for expelling the fluid from the pressure chamber, a pressure mechanism for generating an expelling impulse or force, and a transfer body coupled to the pressure mechanism, wherein, in an initial position the transfer body is arranged at a distance away from a contact point for transferring a force or impulse onto the piston. The invention encompasses a method for injecting a fluid wherein a transfer body is freely accelerated for a distance and strikes a contact point thus generating an initial impulse or pressure to expel the fluid.