The design concept of a simple freight elevator is as follows:

1. Determine the load capacity and operating speed. According to actual needs, set the carrying capacity of the elevator to not exceed the specified maximum value (such as 500kg), while meeting the general efficiency requirements for transporting goods; Choose the appropriate lifting height and transportation distance range while ensuring safety to determine the lifting/lowering rate of the elevator. For convenience, constant speed, acceleration, or deceleration functions can also be set to meet the needs of different scenarios. 2. Choose the type of power unit and traction system and complete the installation configuration, taking into account factors such as equipment stability and safety to ensure that it can withstand certain pressure and operate normally in various environments

The above content is for reference only. Specific implementation may need to be adjusted and optimized according to actual situations. Please note that this design proposal is a complex process that requires relevant knowledge and skills to be successfully implemented. It is recommended to seek advice from individuals before carrying out any substantive operations.