Metal Mechanical Transmission Teaching Instrument Senior Middle School Physics Experiment Model.    Description: Item Name: Mechanical Transmission Model;  Weight: 2000g;  Size: 32*21.5*15.5 cm;  Material: Metal, Environmentally Friendly Plastic;    Structure principle: This mechanical transmission model includes 6 transmission forms: belt drive, worm wheel drive, chain drive, cylindrical gear drive, bevel gear drive, and friction wheel drive. In order to facilitate the experiment and improve the observation effect, the instrument is driven by a DC motor. First, the DC motor drives the worm through the belt to complete the belt drive, and then the worm drives the turbine to achieve the worm drive. After the above two decelerations, the turbine shaft drives the next chain to rotate, and then it is driven step by step. It is cylindrical gear transmission, bevel gear transmission and friction wheel transmission.    Instructions: This instrument needs to be equipped with a DC power supply (DC power supply please prepare your own). After placing the instrument horizontally on the table, insert one end of the connecting wire with a plug attached to the instrument into the power socket of the instrument, and the other end to the DC output of the power supply. The power supply voltage is adjusted to DC6V. Turn on the power and the instrument enters the working state. Adjusting the power supply voltage can change the operating speed of the instrument, and changing the polarity of the instrument power can change the direction of rotation of the instrument.    Note: 1. Do not make the instrument work under a voltage above DC9V, otherwise it will damage the motor and accelerate the wear of various parts.  2. Before use, add proper amount of lubricating oil or sewing machine oil to the two ends of the worm shaft and the meshing part of the worm shaft and the turbine to reduce the noise caused by friction.  3. The instrument should avoid collision and falling. It should be placed in a cool and dry place when not in use. If you find that the fixing screws are loose, please tighten them in time.    Package Included: 1 x Mechanical Transmission Model;  1 x Power Cable;  1 x Manual