The hoisting system of the car is mainly driven by the lifting motor, which provides the system pressure through the oil pump to achieve the lifting function. According to the requirements of a series of lifting height, the gantry structure can be generally divided into single level gantry, two level gantry and three stage gantry. These different types of portal frames basically require full free lifting function. In addition, we should be able to choose different types of fork, such as the distance between the two forks, the length of the fork and so on, according to the specific circumstances of the user's use of the tray. Due to the requirement of the overall size of the vehicle, the lifting motor and the oil pump usually use the assembly structure (also called hydraulic workstation or power unit, etc.), which makes the structure more compact and greatly reduces the occupied space. At the same time, for the lifting oil cylinder, for the sake of safety, the safety valve is required to prevent the accident caused by the damage of the pipeline. 
At present, the vehicle mostly uses 24V power, and adopts MUSFET system to control the driving device to achieve stepless speed regulation, which is conducive to improving the smoothness and efficiency of the operation. Some vehicles also have voltage, ammeter and so on, to provide the operator with the use of power, timely charging, to avoid the occurrence of excessive discharge. 
The brake of the vehicle consists of two sets of brake systems. A set of mechanical brake systems attached to a walking motor: the other is a regenerative braking that is implemented by the electronic control reverse current by the speed drive device. For this vehicle, it is required that when the handle is in a certain range of vertical position and horizontal position (i.e., near the limit position at the two ends of the joystick's moving area), the vehicle should be in the braking state and the normal driving state in the middle area. 
The vehicle is more common with three, four and five wheel structures. Three structure is composed of two front wheels and a driving wheel, a driving wheel in the rear wheel structure is composed of four central; two front wheel, a driving wheel and a balance wheel, wherein the driving wheel is located in the rear of the body, the other side of the balance wheel in the rear; five wheel structure is composed of two front wheels, a driving wheel and two supporting wheel, the driving wheel in the rear on both sides of the central position, and two supporting wheels are located in the rear. 
The pedal of the vehicle must have the function of dual-use. When the pedal is put down, the driver stands on the pedal for manipulation. When the pedal is taken up, the driver can use a walking operation. A barrier should be designed on both sides of the pedals, while the self pallet truck does not specify this requirement. It ensures that the driver can still operate smoothly when the vehicle turns.