There are many types of structure of the fall prevention device of the mechanical three-dimensional parking equipment, and there are two types of use in general: One is the usual fall prevention device: it prevents the carrier or the vehicle board from falling when it is in a static position in the sky The device is called a static anti-fall device; the other is the dynamic anti-fall device, that is, a device that can prevent the carrier or the vehicle board from falling during the movement process. Different types of parking equipment and different operation modes (passenger-vehicle sharing, quasi-unmanned, and unmanned) parking equipment have different requirements for the anti-fall performance of the three-dimensional parking equipment. The static anti-falling device is mainly applicable to the lifting and traverse type, simple lifting type mechanical stereo parking equipment. For other types of three-dimensional parking equipment, such as unmanned and quasi-unmanned vehicles, when vehicles or personnel must enter and exit the carrier or vehicle board, the carrier or vehicle board has a height drop of more than 500mm, and there is a possibility of falling. The lifting transporter or the vehicle board fall from outside to protect people or objects. These parking devices should also be equipped with such a fall prevention device.

One of the effective commonly used dynamic anti-falling devices for three-dimensional parking equipment is safety gear and speed limiter. It is mainly used for passenger-vehicle ride-sharing, which is basically to effectively protect personnel. In China's current standard for three-dimensional parking equipment, there are the following requirements for car-specific lifts: "In the lifts for passengers and vehicles (except for hydraulic straight-top lifts), safety gears and speed limiters should be installed." Not only that, the safety gear and speed limiter are more clearly required in the regular inspection rules of lifting appliances. "Forcibly driven and traction drive lifts (except hydraulic straight-top lifts) are equipped with safety gear and speed limiters (man Car sharing type), the safety gear installed on the elevator with a speed greater than 0.63m / s is a progressive safety gear. When the elevator falls or descends, the safety gear can operate and cut off the power supply of the drive system , Speed ​​limiter and safety gear have type test certificate. " In the safety specifications for elevator manufacturing and installation, it is also required: "If the car is equipped with several sets of safety gears, they should all be progressive." The three-dimensional parking equipment is hydraulically lifted up and down. The anti-crack valve provided to prevent the carrier from falling is rigidly connected to the cylinder. When there are multiple parallel cylinders, it is difficult to synchronize the multiple anti-crack valves to cause the carrier to fall. When tilted, one anti-crack valve can be shared.