Door handle is an ambiguous term, with door latches, bars, and knobs included. We differ in size, form, and materials depending on the geographical location and its position in time. The only constant is their function: an attachment for opening or closing a door.
Knobs and handles functions The earliest surviving doors are about 5000 years old. Door handles became a necessity shortly after the invention of the pivoting mechanism as instruments to manipulate a gateway. To most, pivots are simply referred to as hinges but there are almost as many hinge styles and configurations as there are handles.Avant-Garde Hardware- Door Handles
The simplest handle is a projection of a pull-or push-on the side opposite the hinge. The positioning of the handle is usually where it offers an optimum mechanical advantage; most doors are controlled as levers of second class. Doors with central pulls or loops, or a focal point at a position other than one door side, use the concepts of first or third class levers.
Hinged rings are centrally placed depictions of door handles in paintings dating from the first century CE. The modern knocker at the door is a vestige of this traditional door handle design. Doors were typically secured by bars and brackets to prevent either intentional or accidental opening of doors.
Knobs with latches and bars In the course of time, wide crossbars used to lock a door were replaced by sliding bars, controlled by a handle attached to a bar and projected through a slot in the frame, or as a pivoting bar-often called a latch-that could be lowered into a similar slot on the door jamb. In Colonial America, a lock string threaded through a hole in the door near the handle, was the operating mechanism for a small pivoting pin. There are-probably apocryphal-accounts and references implying that this mechanism was a workaround for heavy taxes and that the colonists could use only door latches or locks imported from England as a crown edict.
The handles and locks were combined into a single unit around the middle of the 18th century, the earliest known examples being levers that both controlled the latch and acted as a pull for opening the door.
The handle, as it now exists, is a relatively new invention dating back to the mid-19th century, with the first American patent dating back to the 1850s. Over the Victorian Era (1830-1900), handles and knobs experienced a massive period of growth and development. Hundreds of variations on the door handle theme combined with modern manufacturing techniques have made door handles available to practically all. Latches faded in popularity and use, relegated to service in barns and similar outbuildings where their simplicity and functional design trump outward appearance.
Handle value added functionality These handles serve multiple functions today. Among these functions may include lock and key systems, electronic locks, mechanical or electronic push button access, high-security features and many other applications other than a simple push-pull system for opening or closing a door.