Latches are used to temporarily join two moving parts. They act by releasing the coupling, allowing the two parts of the assembly to separate. They are attached to doors and enclosures. These are used in seat belts. Different designs have different actuations, mounting options, and hold-ups.
General door latches close gates and doors. They can be a sliding bolt that stops the door from swinging or a hook that keeps it closed to prevent sliding and swinging.
- Deadbolts door latches cannot be extended with keys or pulled back by knobs. It does not include a bolt-spring. It doesn’t latch automatically when the door closes. The bolt can’t be pulled to retract it once extended.
- Doorknob deadlatches have a long history. A deadlatch typically has two bolts. The main bolt is used to keep the door shut, while the smaller bolt protects against tampering. Each bolt contains a spring. The main bolt has a cylindrical end with a rounded top; the deadlatch lies next to it. As the door closes and the main bolt slides against its strike plate lip, the main bowl will slide in. The bolt retracts temporarily. It looks after the main bolt is in its place.
Types Of Latches
- Bolt Latch
Bolt latches come in the form of a bolt. The bolt can be held by the barrels, which lock the latch. The handle can be passed through the non-continuous loop. To lock or unlock a bolt-latch, simply slide the bolt in the socket.
- Spring Latch
Spring latches are similar in design to bolt latches. However, they have an automatic bolt extension. Spring designs do not allow bolts to be extended.
- Compression Latch
Cam latches called compression latches have modified arms that compress the frame and door when closed. When you push the door and activate the latch, or turn the latch multiply, compression can be created.
- Draw Latches
A toggle latch or draw lock has a part that is always in tension. They are used in applications that require strong closing force to prevent water, dust, or leaks.
- Over Center Latches
Over centre latch have minimal actuation force and strong closing forces. The lever is designed to create a mechanical advantage so that enough tension can be created with minimal force.
- Cane Bolt Latches
The cane bolt latches are simple and have one L-shaped spring-loaded bolt connected by two knuckles. Spring-loaded bolts engage the keeper when they are turned and forced forward. They can also be reversed to remove the latch.
- Pawl Latch
A pawl locking mechanism has a rotating cam that can lock and unlock. The latch can be engaged with a keeper/door frame by turning the quarter-turn of its pawl.
- Multi-Point Latch
Multi-point locks have a long handle with 2 bars. The handle turns to engage and disengage the keepers.
- Quarter-Turn Latches
Quarter-turn latches refer to several types of cam-engaged locks. Quarter-turn locks can be opened and closed with various tools, keys, and methods.
- Snap Latches
Trigger locks are flush-mounted to enclosures or doors. They’re locking compression latches.
- Twist Latch
Twist-latches, also known by the name butterfly latches or simply twists, is made up of a rotating cam and a straight or curved slide. The latch keeper is a flat metal component that connects the slide and bracket.
Bars are primitive latches. They are made from bigger beams and bolts. They can hold large and heavy doors and gates.