Visual control.
A set of traffic light fixtures was installed inside the building for inspection by forklift truckers, and one set was located outside the building for inspection by truck drivers.
Auditory control. If the truck does not have a rear collision bar or the combination of the two is not suitable, a buzzer installed inside the building will sound to alert the driver of the truck. In this case, the vehicle must first be secured in other ways (e.g. using wheel wedges, etc.).
The prerequisite for the proper use of the hook is that the vehicle must be parked tightly against the platform bump rubber. The lifting of the hook is controlled by the operator in the warehouse who operates the lock (lift) or unlock (drop) button on the control box.
In normal mode, the hook is in the reset state at the bottom of the restrictor, at this time, the signal light inside the warehouse emits a red light, indicating that the truck is not fixed, and the green light of the signal light outside the warehouse will flash, indicating that the truck can freely enter or leave the loading dock.
Once the vehicle is parked, the terminal operator can press the lock button, the hook will slowly rise, hook the rear collision crossbar, when the rear collision crossbar is correctly locked, the signal light will be switched synchronously, that is, the internal signal light will switch from red to green (indicating that the truck has been locked), and the external signal light will switch from green to red (indicating that the truck cannot be moved). When the loading and unloading operation is complete, the operator at the terminal will press the button to return the hook to its lowest position.
The vehicle can be effectively locked when the latch can be raised unhindered until it fully enters the horizontal crossing section of the rear crash bar. If the horizontal crossing of the rear impact bar of the truck is missing, blocked, deformed, or too far away from the rear of the vehicle, it is not possible to effectively lock the truck, in which case the signal light glows red or the buzzer sounds. In this case, the vehicle must be secured in other ways, such as triangular wedges tucked under the wheels, to ensure safe loading and unloading operations.