Little dictionary of technical terms for Schwepper lock products

Essential functional components of mortises

What is a 'handle hub' ?

The handle hub takes the square spindle of the handle in order to retract the latch inside the lock through the turning motion of the same. This process allows the opening of the door.
What is a 'lock latch'?

The lock latch keeps the door shut. In order to open the door, it must be retracted. There are several designs for the lock latch:

  • single piece latch
  • anti-vibration latch
  • rolling latch
What is a 'deadbolt' ?

The deadbolt prevents the opening of the door and regulates the access rights through the turning motion of the cylinder by key. The deadbolt is being driven out or retracted through the turning motion.
What is a 'faceplate' or 'front plate' ?

The faceplate is the visible part of the lockcase. The faceplate, the latch and the deadbolt are the only visble parts of a mortise
What is a 'WC hub' ?

The WC hub takes the square spindle of the olive or thumbturn, that retracts or drives out the deadbolt from the inside - analogue to the turning motion of the cylinder.


Essential dimensions of mortises

What is the 'backset'' ?

The backset is the distance from the top edge of the faceplate to the center of the cylinder hole respectively handle hub square.
What is the 'distancing' ?

The distancing renders the dimension from the center of the handle hub to the center of the profile cylinder hole / WC-hub hole / key hole. The standard dimension in shipbuilding is 75mm.
What is the 'latch protrusion' ?

The lock latch sticks out 14mm in its forward position according to the DIN standard in shipbuilding - this is called the latch protrusion. Other technical standards for the latch protrusion are:

  • 16 mm according to DOT (Department of Transportation)
  • 19 mm according to USCG (US Coast Guard)