lock and block system मीनिंग इन हिंदी

उदाहरण वाक्य

1. It adopted a proprietary signalling system based on Sykes lock and block system.
2. In 1951 a rear-end collision took place at Stobcross; a signalman worked the block instruments irregularly, and there were two wrong-side defects in the lock and block system that enabled this.