Closed-circuit televisions of various specifications are essential equipment in audio-visual education. In order to ensure the quality of the image and sound, and to ensure safety, the TV should have an appropriate placement method. One of the existing placement methods is to suspend the ceiling, the bottom of the TV is raised to a height that cannot be touched by the hand when a person is standing with a screw drive pair, the power is turned on when it is used, and the TV is lowered to a suitable height. The second method is to hide the TV and its wire rope transmission device in the ceiling. The third method is to fix a closed box on the wall and open the door lock of the box during class. These three methods of placing the TV on the floor can provide a certain degree of protection and meet the requirements of teaching and scientific research, but due to the limitations of the device itself, the protection has a certain limit. For example, a person can stand on a stool or other objects, or climb to the ceiling, or touch the TV by breaking the door lock. In addition, they have their own shortcomings from the perspective of vision, beauty and maintenance. Such as suspended ceiling installation, the bottom of the TV is 80 cm below the ceiling. The six sides of the TV are exposed, unsightly, and have a feeling of falling, and must be installed under the steel plate on the roof of the pre-buried building. The concealed transmission route in the ceiling is long and the wire rope is easily damaged. Maintenance must be carried out in a narrow space. The room must have a certain height of ceiling installation layer. The ceiling must be opened in and out of the hole, and there is also a feeling of falling. The above two installations need to be in a predetermined position, and movement is impossible, and the top surface of the important building that constitutes a beautiful environment is damaged. The method of placing a fixed closed box on the wall makes people feel shaky, but the outer box is huge in size, which is inconsistent with the tidy indoor facilities. Under special circumstances, the existing method of placing TV sets cannot provide safety protection.
