The load-carrying capacity of eccentric joints with eccentric connectors to a great extent determines the strength of structural nodes of case furniture. The distribution of internal forces generated while forcing torsional deformations of the furniture body (Dzi^gielewski and Smardzewski 1995) results in the fact that in structural nodes that join the side walls with the […]
Category: The History of Furniture Construction
Strength of Separable Joints
Strength of Screw Joints As an example of the strength of screw joints, let us consider the widely used method of fixing the rear wall to the side walls, bottoms and top (Fig. 7.63). On the number and spacing of connectors bx, ay, depends not only the stability of the rear wall, but also on […]
Strength of Inseparable Joints
Knowing the distribution and values of external forces between board elements of the furniture body, the strength of appropriate connectors can be determined and the number of joints attributed to the length of the board’s edge can be therefore designed. Table 7.9 provides geometric examples, as well as the strength criteria for designing dowel joints […]
Strength of Case Furniture
7.2.3.1 State of Internal Forces in Corner Joints The primary determinant of the strength of a furniture body is the strength of its joints. Therefore, the forces acting on the nodes of a loaded construction must be established and the strength of joints specified. The previously assumed reservations that the boards of the furniture body […]
Stability of Case Furniture
Due to the safety of the user, the stability of furniture is probably the most important characteristic. As far as fractures of elements or cracks in the joints cause a gradual loss of stiffness in the construction, depending on the size of these defects, the loss of stability of the furniture, especially of a large […]
Stability of Board with Discontinuous Support on Perimeter
Huber (1923) was the first to analyse the scheme partially fixed elastically on the perimeter of an isotropic board, subject to shearing (Huber 1923). He proposed to adopt the function of a curved shaped board in the following form: nx ny n ( a w = A sin sin sin x — y. (7.178) b […]
Stability of Board with Fixed Support on Perimeter
The method of completely attaching the rear walls of furniture in the body by gluing, due to the inability to disassemble, has never been used in industrial practice. From the cognitive point of view, to check the theoretical assumptions,this example should be regarded as necessary. Timoshenko and Gere (1963), when presenting the approximate method for […]
Stability of Rear Wall
In addition to torsional loads, the board elements also shift shield loads, that is forces lying in their plane. Hence, for flaccid elements, in this case the rear walls, the possibility of the loss of stability occurs (Smardzewski 1991). Therefore, it is necessary to check the stability of this element for the most unfavourable load. […]
Stability of Side Walls
Operational load of the top, acting along the side wall of the furniture body, depending on its intensity, can cause a change in the shape which is the result of the loss of their stability. From a mechanical point of view, the side wall constitutes a board in which one longitudinal edge is free, the […]
Stiffness of Screw Joints
Screw joints of case furniture belong to the group of susceptible connections, for which the total stiffness of the system depends on the stiffness of all its components. In engineering calculations, using models of these connections as perfectly stiff nodes it seems too optimistic, while articulated models are too unfavourable. Only the susceptible models allow […]