Entrance door locks Surface-mounted, square rim locks have been used on doors since the late Middle Ages. During the Renaissance and Baroque periods in particular, these locks became important elements in upper-class buildings, and were intricately decorated. Technologically, they were slam locks or tumbler locks. This section will primarily be about surface-mounted door locks on entrance doors, with lock cylinders that were introduced and manufactured between 1850 and 1950. I call them entrance door locks because they were originally intended for the rapidly growing housing market in big cities from the 1880s on. The locks were attached on the inside of entry doors to apartments from the stairwell. Entrance door locks were first manufactured in the United States and later in Europe in several different versions. Entrance door locks with lock cylinders When Linus Yale Junior (1821–1868) patented the lock cylinder in the mid-1800s, it paved the way for a whole new type of door lock, which became so widely appreciated that they are still manufactured and used worldwide today, though in a modernized format. This type of lock can be described as a chamber lock, cast-iron traditional lock with lock cylinder, replacement cylinder lock, pin-tumbler lock, or most commonly cylinder night latch. This new idea of a combined lock, with a separate box for the bolt combined with an independent lock cylinder, was a more manageable design than previous lock types. The cast-iron lock housing took up very little space; the ingenious, replaceable cylinder made the lock very safe; and the key was minimal. The locks could be manufactured in large series, were easy to install and virtually never wore out. The first lock cylinders had simple keys punched out of very thin sheet metal. Today’s locks and security solutions Welcome to ASSA ABLOY’s product pages for more information about today’s locks, access control, mobile keys with NFC, door automatics and more. In the ASSA ABLOY solution pages you can experience lock and security solutions for any door opening.