Patent ID: 7440025
Filing Date: 2008-10-21
Classification: G08B

Abstract:
1. A defogging device for a surveillance camera having a case with a front end, an inner cavity, an inner surface and multiple threaded seats formed on and protruding in from the inner surface near the front end of the case, and each threaded seat having a threaded hole facing the front end; a surveillance camera mounted in the inner cavity of the case and having a lens, a camera mechanism and a power source; a washer mounted in the front end of the case against the threaded seats and has an inside surface and an annular groove formed in the inside surface of the washer; a lens cover mounted in the annular groove in the washer and having an exterior surface, a center and an outer edge; a retaining ring mounted against the lens cover and holding the washer and the lens cover in the front end of the case; and multiple fasteners through the washer and the retaining ring and into the threaded seats to hold the lens cover in the front end of the case, and the defogging device comprising a heating device adapted to be mounted on the lens cover concentrically with the camera lens and to melt frost and dissipating moisture on the lens cover and having a circuit board for comparing ambient temperature to a preset temperature and activating the heating device and that has a power cord connected to the circuit board and the heating device and comprising