Image Number 2 for United States Patent #7749187.
A needleless injection device with a lower part receiving the agent cartridge and an upper part providing the energy needed for injection. The upper part contains energy store units capable of elastic form-change. Rotating the lower part in relation to the upper part causes the lower part to move along the longitudinal axis toward the upper part, resulting in the tension state of the energy storage structural elements. Furthermore, the device has a lock maintaining the tension of the energy storage units and component to release the lock. Among the energy storage structural parts there is at least one start unit capable of storing at least 60% of the total discharge energy (pressure), with the reversible elastic distortion not exceeding 25% of the internal length of the agent cartridge. The device has separate structural components for stretching the start unit and limiting its relaxation.