| 摘要 |
FIELD: physics, optics.SUBSTANCE: invention relates to external surveillance equipment and means for the protection of the said equipment from unfavourable external effects, and more specifically to a method of protecting the optical window of a video camera cover from dirt and a protective cover for implementing the said method. The disclosed method comprises placing on the front end of a cover a tube in the form of a pipe with an arbitrary cross-section such that the inner walls of the tube form the boundaries of the visibility zone of the video camera; through at least one opening in the lower or lateral part of the protective tube, feeding an air stream by creating a temperature difference between air inside the tube and surrounding air, or by the forced generation of excess pressure inside the tube, air is fed into the tube through an air duct mounted in the lower or lateral side of the video camera cover and linked to the surrounding medium through an air inlet. The protective cover comprises a housing, the front end of which has an optical window which opens inside the tube, which is in the form of a pipe with an arbitrary cross-section, the inner walls of which form the boundaries of the visibility zone of the video camera, wherein the lower or lateral part of the said tube is provided with at least one opening through which the rear part of the tube closest to the housing is linked to the external environment through an air duct attached to the lower or lateral wall of the housing of the cover, wherein an air intake element is placed inside the air duct to generate excess pressure inside the tube.EFFECT: minimising the number of cycles and the cost of maintenance of external surveillance equipment and maintaining high performance thereof and quality of operation for a long period of time, as well as preventing the formation of dirt on the optical window of an external surveillance video camera, including dust, water droplets, snow, condensation and ice.18 cl, 2 dwg |
