The doors in case furniture enable to close a space limited by the case of the cabinet and also ensure access to its interior. Currently, in industrial practice, a huge number of various types of hinges and fittings are used, which ensure the rotating motion of a door. Figure 4.63 illustrates the way in which a box hinge in a door and a guide in a side wall is set. Depending on the construction of both of these elements, the door can open by an angle from 110° to 360°.
Depending on the way of positioning of the door in a front build, we distinguish constructions with lift-off doors (Fig. 4.64a, b) and constructions with mortise doors (Fig. 4.64c). For each of these constructions, a different guide and hinge with a different shape of the arm are required.
When designing the mounting system of a door in the furniture body, the designer should foresee the method of solving the doorstop. The easiest scheme of a collision-free work of a door is leaving a small gap between the edges (Fig. 4.65a). The door is then rested on narrow planes of the bottom and the top boards (in the construction of lift-off door) or limiting dowels (in the construction of mortise door). To eliminate the gap between the wings of the door, often wooden or plastic doorstop strip is used (Fig. 4.65b), screwed to one of the wings. Solving the way in which the door is supported is identical as in the previous construction. The use of a durable (fitted to the body) doorstop strip (Fig. 4.65c) solves both the issue of the gap between the wings of the door, as well as their support system. If the door has
Fig. 4.63 Way of setting: A guide, B runner and C box hinge in a door
Fig. 4.64 Construction of with furniture with a door: a lift-off set on an independent side wall, b lift-off set on a shared vertical element and c mortise set on an independent side wall
been made of wood or is finished with wooden laminated boards, then the doorstop can be created by the appropriate milling of these boards (Fig. 4.65d).
The number of hinges mounted to the door wing depends on the weight of the given element and the anticipated operational load. From the mechanical point of view, the use of more than two hinges on one door wing brings the construction to an over stiff scheme with zero passive forces forming overvalues of the static system. In practice, however, the rule of selecting the number of hinges depending on the height of the door is adopted (Fig. 4.66).