bell, surname
鈬 centers on a bell, specifically a large hanging bell used in temples or for signaling. The surname sense is a rare application of the same character.
鈬 combines 金 (metal) with 尺, which likely contributes the sound タク. The character originally referred to a metal bell.
The left side is metal 金, and the right side 尺 looks like a measuring ruler. Picture a large metal bell being struck with a ruler-like mallet to produce a resonant sound.
For タク, imagine the bell making a deep 'tock' sound when struck: tock -> タク, and the metal bell rings out.