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Zagadnienia teorii mechanizmów w podręczniku konstrukcji Karola Stadtmüllera

Jonak J., Pylak K.

Interdisciplinary Journal of Engineering Sciences

2018

Vol. 6, no. 1

21--26

Pierwszy polski podręcznik podstaw konstrukcji maszyn dla inżynierów Karola Stadtmüllera zawiera również treści, włączane tradycyjnie do obszaru teorii mechanizmów. Praca przedstawia przegląd tych zagadnień i sposób ich ujęcia przez autora. Jest kolejną pozycją z cyklu poświęconego historii polskiej szkoły teorii maszyn i mechanizmów.

The handbook by Karol Stadtmüller is the first Polish machine design handbook for engineers. It also contains issues which belong traditionally to the mechanism theory area. The paper presents a review of these issues and the way they were treated by the author. It is a successive publication from the series dedicated to the history of the Polish school of the mechanism and machine theory.

Kartki z wczesnych dziejów tribologii

Burakowski T.

Tribologia

2007

nr 2

75-91

W artykule w aspekcie historycznym omówiono: pojęcie i rodzaje węzłów tribologicznych - skrawaniowych i kinematycznych, przedstawiono początki wykorzystywania tarcia ślizgowego i tocznego, przedstawiono rolę tribologii w przenoszeniu napędu, rozwój środków smarowych i prac naukowo-badawczych w obszarze podstaw, zwłaszcza teoretycznych, tribologii oraz podano globalną energochłonność węzłów tribologicznych.

From several hundred thousand years mankind positive (making the fire, tools sharpening) and negative (friction wear) influence of friction on the products of human activity is known, in spite of friction idea to ca. 1500 A.D. was unknown. The friction in the area contact of two mobile bodies was came into being. The area contact of two mobile bodies, in relation one to other, with lubricant fluid eventually - it is a tribological point. The development and exploitation of tribological point began several hundred thousand years and continue up today. In the table 1 chronological development of the most important achievements concerne friction was done. From the most ancient time a development and exploitation of tribological points contain two general directions: 1) a materials working by tools: - separating, disassemblying (in this: cutting), machining more soft materials (a stocks) by more hard materials (a tools): in thouse processes must participate a friction; such tribological points - there are a machining points', - plastic forming of materials; this points - there are a deformation points; 2) a decreasing or increasing of friction between collaborating by motion machine element; such tribological points - there are machine bearings or - by generally - kinematics, and their variation - there are sliding points and rolling points. Apreaprototype of machine point was hard wood-stick related by man - in the more soft material: warm stand up by relating stick - incadescent soft material (Fig. 1). It was ca. 100 000 B.C. Tipically machine points appear ca 7 000 B.C., in stone epoch, with the beginning of smoothing (honing) of stone tools. A preprototype of the machine, in which was utilized sliding friction was a drag - in the form of two bind word sticks drawn after the ground, on which a load was placed. A little later, ca. 8 000 B.C., was utilized a wood siedge probably. Is sure, that in ancient Egypt and in Asyria ca. 1930 B.C., a heavy stone loads was transported by a wood siedge (Fig. 2 and 3). Ancient Asyria inhabitants replace sliding friction - by rolling friction: put under the siedge a wood round beam, on which the siedge was rolling. A sliding bearings was known: ca. 4000 B.C. - from stone, ca. 300 B.C. in China - from bronze (after from cast iron), ca. 100 B.C. in Roma - from iron. When the wheel was appeard (Fig. 4) - in Midle-East Asia, at ca. 3500 B.C.: land whels and jolleys - probem of good bearing stand up. After sliding bearing rolling bearing was appeard, in which at first a rolers from hard wood was made and after a balls frome hard wood too. A heavy stone blocks in special wood wheels was supplied - for change sliding friction by rolling friction (Fig. 5). China men Ge Xu a sliding wheel to wheel-barrow appicated (ca. 100 B.C., in Europe-ca. 1100 A.D.). A power transmision was a separate problem. In 976 A.D. China men chain drive utilized. After 1000 years later the Renaissance genius, Leonardo da Vinci the conception of line and belt drive, ball bearing and gear transmismision (hypoid, worm) gave and the conception of frictions force and coefficient force indroduced. A gears in Egipt and in Grece was utilized - Arysthoteles (ca. 335 B.C.), Witruwius and Pappus from Alexandria (Ill/TV B.C.) about it mentioned. A bearings (particularly ball bearings) from 1883 A.N. - the first automat for hardned steel ball grinding (P.M. Fischer) began to be utilized. Before Second World War a porous sintered self-lubricating bearings was appeard. Some 500 years ago Leonardo da Vinci constate, that "Eeach substance, without regarde, what is your lubricant property, introduced between two fractioned bodys, a friction process appease". As a lubricant fluids were utilized: a water, greasio from wood tar obtained and by prolonged petroleum heating, vegetable oils, mineral oils (from the beginning of XX age) and syntetic oils (from ca. 1930 A.D.). In the beginning of 1940 A.D. a sliding bearing with water lubrication practically was used.