Why do I see several patents with different names and the same realization principle? But they all have their own patent numbers. What happened?

It should be a practical model, right

The utility model has no substantive examination.

So it is very likely that the structure is the same.

In addition, even if the principle is the same, there are differences in some details, or different protection scopes will be formed according to the different writing methods of the claims, thus forming a number of patents.