Patent ID: 6858020

Claim:
In a handheld syringe assembly which electrically connects to an electrically powered dispensing means which reloads a liquid to be dispensed through a conduit to the syringe assembly either through (I) a disposable needle and hub assembly or (ii) a hub, mounted on a body of the syringe assembly, after injecting a dose of the liquid, the improvement which comprises: (a) a permanent magnet mounted on the body; and (b) a magnetically closeable reed switch, with spaced apart reeds, mounted on the body adjacent the magnet and with an electrical connector to the reeds for connection to the dispensing means, wherein the reed switch or magnet are moveable relative to each other on the body, wherein upon the movement a magnetic field from the magnet closes the reed switch in one position of the movement to turn on the dispensing means and at another position of the movement the reed switch is opened away from the magnetic field of the magnet to turn off the dispensing means.