摘要 |
<p>1,235,243. Shuttered keyhole lock. SOCIETE D'EXPLOITATION DES BREUETS NEIMAN, S.A. 30 July, 1969 [2 Aug., 1968], No. 38239/69. Heading E2A. A cylinder lock having an insulating disc 3 with contact plates thereon has a pivoted shutter 4 biassed to normally obscure the keyway and provided with a contact, which contact establishes continuity between the contact plates when it is pivoted by the act of inserting a key in the keyway. The shutter may be of plastics material and may have an integral arm 4', Fig. 3, not shown) to provide the biassing alternatively a separate metal spring may be provided. The lock is provided in a motor vehicle to sound an alarm if the key is left in the lock.</p> |