| 摘要 |
<p>The speedometer is fitted with four sets of contacts, representing four set speed limits. One of the limits is selected by the driver, depending on which road he is travelling, and with the set limit indicated externally to the vehicle by one of the set of colour lights. This enables police, etc., to determine if the correct limit has been set. As soon as the driver exceeds the limit the vehicle horn is sounded, and is not cancelled until the speed is reduced below the limit. An interlock prevents the driver from selecting a higher limit to cancel the horn. The system relieves the police from tedious radar traps, etc.</p> |
