620961-A is referenced by 2 patents.

620,961. Retractive switches. CRABTREE & CO., Ltd., J. A., and HILL, W. E. Feb. 5, 1947. No. 3379. [Class 38(v)] A push-button switch has a deformable cup associated with the button to ensure a waterproof assembly. A corrugated cup a of rubber or other flexible material has at its open end a bead k seated around a spigot part m of the switch casing. At its closed end it has a central depression c for engagement with the push button d of the switch, a cavity containing a moulded part e, and an external flange b which is trapped in an annular groove between flanges f, h of a metal gap g. In a modification, Figs. 3, 4 (not shown), the rubber cup is fixed in the metal cap by means of an annular washer which is forced past spring tongues in the cap.

Title
Improvements in and connected with electric switches of the push button type
Application Number
GB19470003379 19470205
Publication Number
620961 (A)
Application Date
February 5, 1947
Publication Date
April 1, 1949
Assignee
Walter Edward Hill
Crabtree & J A
IPC
H01H 13/04
H01H 13/06
View Original Source Download PDF