Pro-Techtor International
Transmission mechanism of a toy helicopter
 A transmission mechanism of a toy helicopter, including a casing disposed in a housing of the helicopter, a motor disposed in the casing and a gear set driven by the motor to drive a pair of cams. Each cam is formed with a peripheral groove within which two rocking arms are driven to regularly swing. The rocking arm simultaneously drives a linking lever and a torque spring. The torque spring drives a lifting support shaft to move up and down. The linking lever is levered about a fulcrum and has an inclined board at one end. The inclined board has an inclined side for contacting with two seat boards pulled by springs, whereby when the linking lever swings, the inclined side of the inclined board outward pushes the seat boards. When released from the pushing force, the seat boards are resiliently restored to home position. 
A
A63H
inventional
Tien Fu
Huang