Some aspects of fabric drape

Drape is one of the important factors influencing the aesthetics and functionality of fabrics. Therefore, investigation into drape parameters is important for analysing its behaviour. Drape parameters were investigated from different aspects using the Cusick Drape meter and Image Analyser. Firstly, the influence of time on the drape coefficient and number of folds was studied over 24 hours. Usually, drape is considered as a static, time-independent problem. However, this investigation shows that the drape coefficient of a fabric changes si-gnificantly over a longer time period. Furthermore, the comparison of drape parameters is shown using samples with two different diameters. The larger samples have smaller drape coefficient than those with smaller diameters, and their drape is less changeable over time. Basically, the three-dimensional fabric drape is not an independent fabric property, there-fore, the connection between bending rigidity and drapecoefficient was studied. The last aspect of this investigation was the repeatability of drape measurements, and the establish-ment of the required number of measurements for drape coefficient and fold numbers

Computer simulation of needle and take-up lever mechanism using the ADAMS software package

A knowledge of the interactions between a sewing machinećs mechanisms and the sewing thread in the stitch formation process should help us to understand thread loadings in the sewing process. The aim of this work is to analyse the needle bar\u27s kinematics with the thread take-up lever by using computer simulation. A cyclogram was drawn on the basis of modelling and kinematic simulation of a needle bar with a thread take-up lever, and measurements of the thread tension forces in the sewing process. This cyclogram enables analysis of the interactions between the thread and the elements of the sewing machine. The results of these simulations are curves that describe the movements at characteristic points on the mechanism. These give the possibility of pinpointing the exact positions of the mechanism\u27s elements with respect to the main shaft rotation in the sewing machine

Thread loadings in different measuring positions on the sewing machine

The knowledge of sewing thread tension determined at different measuring locations on the sewing machine is the basis for the definition of the loading magnitudes acting during the stitch formation process and the locations at which they appear, concerning the stitch cycle or the main shaft turn of the sewing machine. During the stitch formation process the sewing thread is exposed to the highest tension in the region between the tension regulator and the thread take-up lever, following by tension in the region between the take-up lever and the needle and in the region in front of the tension regulator. Dynamic tension and tension force are also dependent on stitch velocity

Computer-aided workplace analysis

Analiza delovnega mesta je tako kot medicinska preiskava diagnostični postopek. Tako kakor pacient pri preiskavi pričakuje terapijo, tako tudi delavec pričakuje na delovnem mestu ukrepe. Vsi izidi analize tvorijo izhodišče za ergonomske ukrepe, ki jih sestavljajo tehnološke in organizacijske (re)konstrukcije. Pri tem je osrednji strokovnjak inženir oblikovalec, vzporedno z njim sodelujejo še vsaj medicinec dela, biomehanik ter psiholog. V članku je predstavljena primerjalna analiza delovnega mesta med klasično in računalniško podprto izvedbo, ki temelji na presoji podatkov o držah delavca pri delu (opazovalna metoda telesnih drž in položajev OWAS). Dobljeni rezultati kažejo na ustreznost in prednosti računalniško podprte analize.The analysis of a workplace is a diagnostic procedure, as is a medical examination. The worker expects a remedial action as a result of the workplace analysis just like a patient expects a therapy after a medical examination. The results of a workplace analysis represent the basis for subsequent ergonomic measures that consist of technological and organizational modifications. The central expert involved is the workplace designer (engineer), who is assisted at least by one expert in occupational health (industrial medical officer), and one expert in biomechanics and a psychologist. The paper presents a comparative study of the classical and the computer-aided version of a workplace analysis dealing with the posture of workers at work. The study is based on the assessment of postural data obtained by OWAS (the observation method). The results obtained show the advantages of the computer-aided analysis and con firm its applicability in engineering practice

Ergonomically designed workplaces in leather cutting plant

Namen oblikovanja dela je prilagoditev delovnih mest, izdelkov, delovnih sredstev in delovnih postopkov obliki in gradnji človeškega telesa, telesnim meram, življenjskim dogajanjem v telesu, duševnim pojavom in gibalnim možnostim izvajalca dela. S tem želimo vsekakor razbremeniti delavca ter mu zagotoviti udobno in prijetno delovno okolje, kar bo imelo za posledico zadovoljnega delavca in večjo gospodarsko korist za podjetje. V članku je izvedena raziskava dela na delovnih mestih pri krojenju usnja in na podlagi dobljenih rezultatov so podani predlogi izboljšav. Raziskava na sistematičen način ugotavlja obremenitve in obremenjenosti delavca zaradi delovne naloge, zaradi delovnega okolja, toplotnih obremenitev, obremenitev vida in obremenitev zaradi hrupa. S prav tako ugotovljenim ergonomskim koeficientom pa smo dali možnost za izračun pravilne norme, ki upošteva dovoljene obremenjenosti delavca.The aim of work design is to adapt workplaces, products, working means and working processes to humans, i. e. to the dimensions of a human body, vital processes in the body, psychical conditions and movement possibilities of operatives. An operative should be relieved of stresses and provided with a comfortable and pleasant working environment. This will result in a more satisfied operative and higher economic benefits for the enterprise. The article investigates workplaces in a leather cutting plant. Improvements in work place design are suggested on the basis of the obtained results. A systematic way is used to investigate stresses and strains the operatives are exposed to during performance of their tasks. The stresses induced by a working environment are heat, visual stresses and noise stresses. The ergonomic coefficient that considers the allowed operatives\u27 strains is suggested for the calculation of the right working standard

Computer-aided workplace design

Za doseganje konkurenčnosti podjetja in zagotavljanje produktivnih delovnih mest moramo danes posvetiti več pozornosti vlogi človeka na delovnem mestu. Pritisk na stroške in preobremenitev načrtovalcev dela vodita mnogokrat v slabo oblikovana delovna mesta, na katerih ni mogoče doseči največjih učinkov niti zadovoljstva pri delu. Na tem področju so torej še velike možnosti racionalizacije. Zato potrebujejo danes industrijska podjetja programska orodja, s katerimi lahko ročna in deloma avtomatizirana delovna mesta hitro, stroškovno ugodno, zanesljivo in ergonomsko pravilno načrtujejo. V članku je prikazana možnost oblikovanja delovnega mesta vnaprej, kar je osnovni namen uporabe programskih orodij. Predstavljena sta oblikovanje in racionalizacija obstoječega delovnega mesta z usnjarskim šivalnim strojem z uporabo programskih orodij ERGOPlan, ERGOMas in ERGOMan.If we wish to make a company competitive and to guarantee efficient workplaces, we have to pay more attention to the worker and his workplace. Both, the pressing need to reduce costs and the fact that work-planners are usually overoccupied with work, often result in poorly designed workplaces where neither maximum efficiency nor job satisfaction may be expected. This is a field yet to undergo rationalization. What industrial companies need today are the programming tools with which manual and partly automated workplaces will be designed quickly, reliably, cost effectively and in compliance with ergonomic principles. In our paper we will show how to design a workplace in advance, which is the primary purpose of using programming tools. The approach to the design and rationalisation of a leather sewing machine workplace in an industrial environment obtained by the programming tools ERGOPlan, ERGOMas and ERGOMa is presented