feature on a latch which prevents the latch tongue from being pushed back whilst the door is still closed (the credit card trick, often seen in the movies, but actually pretty hard to do!)
plate on which the moving parts of a handle or knob are mounted.
the distance from the door edge to the centre of the keyhole or handle.
a lock fitted to an internal door which has both a) a spring latch operated by a handle or knob from either side, and b) a privacy bolt operated by a small thumb turn.
a term covering locks of any type used on furniture, such as cupboards, drawers, chests and boxes.
the metal body of a lock or latch containing the mechanism.
the vertical distance between the centre of the keyhole and the hole for the handle spindle.
a type of lock, fitted to sliding doors, having a bolt with pivoting claws which swing out sideways when locked.
a padlock where the shackle is partially hidden by the shape of the lock body - provides resistance against forcing or use of bolt-croppers.
a latch, either rim type or mortice type, which secures the door closed, but can be withdrawn by key from outside and by knob or handle from inside. Latch tongue cannot be pushed back (credit card trick) once the door is shut. See also Nightlatch
standard mortice lock, set into the edge of a door, with a square-ended bolt operated by key or, occasionally, by a thumb turn on the inside.
facility in a rim lock which, using an extra turn of the key on the outside, prevents the latch or bolt from being operated when the door is closed (see also Automatic Deadlocking).
the surround plate for a keyhole.
part of the latch mechanism that contains a square hole, through which the square spindle for the handle sits. Turning the follower moves the latch tongue.
the face of the lock or latch, seen in the door edge, through which the bolt or latch tongue protrudes.
refers to the direction of opening a door and, consequently, which way the bevelled latch must slope in order to operate.
term sometimes used for the striking plate fitted to the door frame which accepts the lock bolt or latch tongue.
a spring-loaded tongue which secures the door closed, but is not lockable. Certain types have now been adapted to lock as well
part inside a lock, moved by the key, which allows the lock to be operated. Generally, more levers means higher security. Most insurance companies now require a 5 lever lock to be fitted to all external doors.
a horizontal handle for operating the latch mechanism. The handles are usually spring-loaded to ensure return to horizontal position after use. Some foreign handles (NOT the ones we sell!) are un-sprung - but this is not a problem as the latch just needs a stronger spring instead.
a recess cut into the edge of a door to receive a mortice lock or latch.
a latch, either rim type or mortice type, which secures the door closed, but can be withdrawn by key from outside and by knob or handle from inside. Often has a 'snib' to hold the latch back if required. Not very secure (credit card trick!) and can simply be opened from the inside unless either deadlocked from the outside (extra turn of the key) or using a locking handle (if fitted) on the inside.
a key that operates a lock is said to 'pass' the lock. If locks are made 'keyed alike' then one key will 'pass' all the locks.
Pin Tumbler Lock
type of cylinder mechanism found on most rim locks. The cylinder contains a line of small pins which, when the correct key lifts the pins to the correct position, allows the cylinder to turn. When the cylinder is rotated the lock is operated.
Rim Lock or Latch
a lock or latch which is fitted on to the inside face/edge of a door.
found in some latches instead of a spring loaded tongue, a bolt made with rollers to engage into the latchplate. Works with either door swing or 'hand'.
circular plate on which the moving parts of a handle or knob are mounted.
a mortice lock containing both a) a latch operated by handles and b) a bolt secured by key.
a small button/switch on the case of a nightlatch used to hold the latch tongue back or, alternatively, to stop the latch being operated when closed.
the square bar inserted through a latch which connects the handles on either side of the door.
Striking Plate (latchplate)
plate fixed to the door frame with one or more bolt holes, into which the bolt or latch shoots. There is often a shaped projecting lip on one side to guide the latch tongue.
locks can be grouped into sets that can then be operated by a controlled distribution of keys. The number of suites is virtually unlimited and can be operated under a Master Key system.