这个部分截面之间的直线Visual indication passed to a train driver to advise the speed, direction or route of the train. There are almost as many types of signals as there are railways but they fall into the following main categories:1) handsignals - used mainly where there are no fixed signals or where the fixed signalling has failed. 2) semaphore signals - a fixed lineside signal where the stop indication is displayed as a horizontally positioned arm and proceed as a 45º or vertical arm. 3) colour light signal - a fixed lineside signal showing light indications to drivers. 4) cab signals - where the indications are displayed in the driver's cab.
" class="glossaryLink ">信号一个信号箱和The first stop signal on the approach to a signal box using the Absolute Block system of signalling
" class="glossaryLink ">进站信号机前方的下一个信号箱
