Control method for controlling retraction of boom, mechanical device and storage medium

A mechanical device, comprising a memory and a processor, wherein the memory is connected to the processor, a computer program is stored in the memory, and when the computer program in the memory is invoked by the processor, a control method for controlling retraction of a boom is implemented, the control method for controlling the retraction of the boom is applied to a hydraulic system which combines retraction of the boom by self-weight with retraction of the boom by pressure, the hydraulic system comprises:

• a pressure retraction motor, a pressure retraction proportional valve and a self-weight retraction proportional valve that are sequentially connected, the boom with non-rod cavity is connected to the self-weight retraction proportional valve, the boom with rod cavity is connected to the pressure retraction motor and the pressure retraction proportional valve, and the control method comprises:
• when the boom is retracted, controlling the self-weight retraction proportional valve to be at a maximum opening;
• obtaining an actual speed at which the boom is retracted;
• controlling a rotation speed of the pressure retraction motor to rise or an opening degree of the pressure retraction proportional valve to increase when the actual speed is less than a preset speed;
• and
• controlling the rotation speed of the pressure retraction motor to reduce or the opening degree of the pressure retraction proportional valve to decrease when the actual speed is greater than the preset speed.

A non-transitory computer-readable storage medium on which a computer executable instruction is stored, wherein when the computer executable instruction is loaded and executed by a processor, a control method for controlling retraction of a boom is implemented, the control method for controlling the retraction of the boom is applied to a hydraulic system which combines retraction of the boom by self-weight with retraction of the boom by pressure, the hydraulic system comprises:

• a pressure retraction motor, a pressure retraction proportional valve and a self-weight retraction proportional valve that are sequentially connected, the boom with non-rod cavity is connected to the self-weight retraction proportional valve, the boom with rod cavity is connected to the pressure retraction motor and the pressure retraction proportional valve, and the control method comprises:
• when the boom is retracted, controlling the self-weight retraction proportional valve to be at a maximum opening;
• obtaining an actual speed at which the boom is retracted;
• controlling a rotation speed of the pressure retraction motor to rise or an opening degree of the pressure retraction proportional valve to increase when the actual speed is less than a preset speed;
• and
• controlling the rotation speed of the pressure retraction motor to reduce or the opening degree of the pressure retraction proportional valve to decrease when the actual speed is greater than the preset speed.