So, you think you know everything there is to know about pivot door hardware? Think again!
There is so much to know about pivot door hardware, that, like a Japanese master, it could take several lifetimes to just to get your foot in the door (so to speak). But the reality is that, the fundamentals are easy to understand without years of dedication and training. Read on while I show you the door to your imagination.
What is a door pivot?
A door pivot is the point around which the door swings. That is, the stationary point (or more correctly stationary line) which connections the door panel to the door frame. In traditional hinge doors, this pivot point is right along or just away from one edge of the panel. In pivot doors this pivot point can be anywhere else, except for the edge.
Because of this varying position, pivot door hinges have several unique constraints.
- They must be on the top and bottom of the door panel
- There can only be two hinges
- The pivot hinges are generally exactly plumb (one over the other)
Typical pivot locations on a pivot door are 1/4 of the width from the wall. 1/3 of the width from the wall. Or directly center.
What is a center hung pivot?
A center hung pivot is a pivot door where the hardware, and thus line of rotation, is placed directly in the center of the door panel. This means that the door rotates around itself, the right side going in while the left going out, or vice versa.
Stealth Pivot Door Hinge
Stealth pivot door hinges attempt to hide their location and function from the operator of the door, or casual on looker. They are inset in to the body of the door and door frame. This obscures any visual signature of the hinge, except for any portion made visible of geometric necessity during standard operation of the door.
In another usage, stealth hinges are mechanical hinges used on “stealth” low observability (LO) aircraft or other LO vehicles. Traits of the stealth hinge include:
- Sharp or precisely curved surfaces designed to minimize radar cross section
- EM or radar absorptive coatings
- Dark or anti-reflective profile (visual spectrum)
- Streamlined design for decreased audio signature
- Various design techniques to reduce heat production and thus thermal signature
Pivot doors have not yet been popular on stealth aircraft, but there are some that imagine an growing market in the future.
What is hinges on the door?
What are hinges on the door? Hinges mechanical contrivances, typically metal or some other durable substance, that allow a moveable wall segment (eg “door”) transform rotationally in 3d space around a linear axis of rotation. These devices will are often two flaps of metal with screws. One flap of each hinge is affixed alternately to a door panel edge and a door frame (a box of wood adjoining the wall to the door). Joining the flaps is a cylinder of metal that serves as the primary bearing for rotation.
Most hinge doors have three or more hinges, which serve to resist any curvature (aka warping) that develops as the door panel ages. Pivot doors are unique because the positioning of their axis of rotation precludes usage of any more than two hinges per panel.