| 摘要 |
<p>In a miniature concealable radio alarm transmitter to be worn on the person, a switch means to activate the transmitter. The transmitter is preferably flat in flat in shape, and includes a small battery which extends across the end of the circuit board. Two spring contact members extend adjacent each end of the battery, within has button-type terminals on its ends. A soft sponge elastomer spacer is fitted between each contact member and its end of the battery. The spacer has a central hole. Finger pressure against either spring member forces it toward the adjacent battery terminal to make contact therewith. To connect the battery to the circuit and energize the alarm transmitter, both spring members must be squeezed toward each other from opposite sides of the transmitter, making contact with each battery terminal. It is thus difficult to accidentally activate the transmitter. The switch means comprises two switches in series. The whole device is preferably cased in a bag-like enclosure of soft flexible material with a cord adapted to be hung around the wearer's neck.</p> |
