Many thanks to Chelsea's official historian Rick Glanvill who revealed
the history behind the 1946 Chelsea Tour badge:

"This tour was to
Denmark and Switzerland in April/May 1946.
We played KB (Middelboe’s team), Odense, Young Fellows (Zurich),
Servette, Young Boys (Bern), La Chaux de Fonds, St Gallen (grr)
and Basel.
Presumably the commemorative lapel badge was handed out to one
of the Chelsea squad."