The categories, models, naming and serial numbers of sewing machines in my country are arranged according to the structure and objects of use of sewing machines. It is composed of two Chinese pinyin letters and two sets of numbers. Each letter and each group of numbers represent a certain meaning.
①The first letter of the model represents the target of use. "J" indicates a household sewing machine; "G" indicates an industrial sewing machine.
②The second letter of the model represents the main structure and stitch shape of the sewing machine, and there are 25 types in total.
③The first group of numbers indicates the sequence code of the machine type.
④ The second group of numbers is the sequence and characteristic codes that represent improvements on the original basis.
