Patent ID: 7661814

Claim:
A hand-held micro-fluid ejection device for ejecting a fluid onto a substrate surface having a horizontal reference axis in a plurality of physical orientations between the ejection device and a substrate surface, the device comprising: an ejection head having an enabled state for permitting the ejection of the fluid onto the substrate surface, a disabled state for blocking the ejection of the fluid onto the substrate surface and a velocity vector relative to the substrate surface, the velocity vector having magnitude relative to the substrate surface and a yaw angle relative to the horizontal reference axis; a position sensor system for providing measured data indicative of at least one of the plurality of physical orientations between the ejection device and the substrate surface, the at least one of the plurality of physical orientations comprising a plurality of relative velocity vectors for the ejection head, each relative velocity vector having a velocity magnitude relative to the substrate surface and a yaw angle relative to the horizontal reference axis; an electronic processor for receiving the measured data from the position sensor system and placing the ejection head in the disabled state if the measured data indicates that the at least one of the plurality of physical orientations of the ejection device exceeds an orientation threshold limit for the orientation between the ejection device and the substrate surface; the measured data comprising a measured relative velocity vector, the measured relative velocity vector having a measured velocity magnitude relative to the substrate surface and a measured yaw angle relative to the horizontal ejection reference axis; the orientation threshold limit comprising a plurality of maximum relative velocity vectors relative to the substrate surface and to the horizontal reference axis; and the electronic processor placing the ejection head in the disabled state if the measured relative velocity vector exceeds at least one of the plurality of maximum relative velocity vectors.