Author: Desislava Hristodorova
- INFLUENCE OF THE TYPE OF UPHOLSTERY MATERIALS ON THE SOFTNESS OF UPHOLSTERY WITH INNER SPRING UNITS
The upholstery with inner spring units, is composed of materials, which have various stress-strain behavior under load. In the work is studied softness and behavior of structures composed of different combinations of upholstery materials. The type of the innerspring unit, materials and thickness of the upper layers are changed. As criteria for evaluation of the specimens are used coefficients of softness and requirements for general deformation of the structure of the upholstery for seat and back elements. Conclusions are made and recommendations for their application in the structure of upholstered furniture.
Keywords: upholstery materials, innerspring units, Bonnell spring unit, Pocket spring unit, structure of upholstery
- STATIC ANALYSIS OF A UPHOLSTERED FURNITURE FRAME MADE OF SCOTS PINE AND PB WITH STAPLE CORNER JOINTS BY FEM
3D geometric model of one-seat frame for upholstered furniture was created by the CAD system Autodesk Inventor Pro®. A linear static analysis was carried out with CAE system Autodesk Simulation Mechanicalâ by the method of finite elements (FEM) simulating light-service loading of the frame.
The orthotropic material characteristics of pine solid wood (Pinus Sylvestris L.) for the rails and particleboard (PB) for the side plates are considered in the analysis. Corner joints in the framewith staples and PVA glue were considered. FEA was performed with regard to laboratory establishedcoefficients of rotational stiffness of used staple corner joints in the frame – case butt joints and end to face butt joints.
As a result, the most loading construction part of the frame with staple corner joints is established – the rear upper rail of the seat where the maximum values for linear displacements,nodal rotationsand stresses are received due to the nature of the applied loading.
Keywords: upholstered furniture frame, staple joints, PB, static analysis, CAE, FEM
- STIFFNESS COEFFICIENTS IN JOINTS BY STAPLES OF SKELETON UPHOLSTERED FURNITURE
The presented study is the result of a laboratory testing under bending stress by collecting arms by corner butt joints with 2 staples type М1/40 of Scots pine (Pinus sylvestris L.) members and boards (OSB, PB, PW) to determine the deformation behaviour of the joints.
The aim of the study is to establish the stiffness coefficients by examining the influence of the material, the reinforcement by means of a triangular wood member and the type of joints on the deformation behaviour of butt joints by staples.
The results obtained could be used as a basis for future research to predict the deformation behaviour of furniture constructions as well as to find their application in the design of skeletons of upholstered furniture.
Keywords: upholstered furniture, end corner joints, staple joints, stiffness coefficients
- STUDY ON THE SOUND ABSORPTION CHARACTERISTICS OF WOOD FROM SCOTS PINE
In this paper, the absorption properties of wood materials from Scots pine (Pinus Silvestrys L.), which are widely used in flooring and wall linings, have been experimentally studied. The frequency-dependent sound absorption coefficient (αp) was determined in octagonal frequency bands with an average geometric frequency of 100 Hz to 2000 Hz. The tests were carried out using an impedance tube, according to the requirements of BDS EN ISO 10534-1:2006. The obtained results are of a particular interest from both scientific and practical point of view, given that the sound absorption coefficient has a decisive impact on the reverberation time. The latter is the main acoustic parameter of a room depending on its intended purpose.
Keywords: sound absorption, Pinus silvestrys, reverberation time