What is CPC H01F21/04?

CPC H01F21/04 is the Cooperative Patent Classification code for “by relative movement of turns or parts of windings.”

How many patents are filed under CPC H01F21/04 (by relative movement of turns or parts of windings)?

Our database includes 42 publications tagged with this CPC code.

Publication counts under this code: 6 in 2024 vs 3 in 2025 (latest complete years).

by relative movement of turns or parts of windings · Cooperative Patent Classification (CPC)

Electric circuits, power, telecommunications, and semiconductors.

Mapped technology topics for this CPC code.

CPC classification statistics
Metric	Value
CPC code	H01F21/04
Official title	by relative movement of turns or parts of windings
Display label	by relative movement of turns or parts of windings
Total patents	42

Year-over-year patent counts classified under this CPC code.

Filing activity over the last five years is rapidly growing.

Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.

Answers are generated from the same data shown on this page.

What is CPC H01F21/04?: CPC H01F21/04 is the Cooperative Patent Classification code for “by relative movement of turns or parts of windings.”
How many patents are filed under CPC H01F21/04 (by relative movement of turns or parts of windings)?: Our database includes 42 publications tagged with this CPC code.
Is patent activity under CPC H01F21/04 growing?: Publication counts under this code: 6 in 2024 vs 3 in 2025 (latest complete years).