求翻译：按结构分为心式变压器和壳式变压器。是什么意思？

According to the structure into the heart shell-type transformers and transformer.

In terms of structure divided into heart transformer and shell-type transformers.

The transformer may divide into according to the use: The distribution transformer, the power transformer, all seal the transformer, the combined transformer, the dry transformer, the oil bath type transformer, the single phase transformer, the electric stove transformer, the rectification transform

Shell and divided into core transformers and transformer of the structure.

Shell and divided into core transformers and transformer of the structure.