| 摘要 |
<p>The pushbutton switch is intended for use in public facilities where it may be exposed to general misuse and to the attempted insertion of foreign objects into its interior. The rectangular button is housed in a case which has a circumferential ring which locks it in position in a steel surround. The button itself, fiting closely in the casing front face, has a flange which limits its forward movement by engaging with the front edges of the casing. There is a sealing ring which prevents ingress of liquids from behind the button into the casing. The switch includes an LED and a light guide within the button.</p> |
