Stanowisko: Adiunkt badawczo - dydaktyczny
Pokój: 237
Telefon: 42 631 35 14
E-Mail: jaroslaw.kaczor@p.lodz.pl
Wykształcenie i przebieg pracy zawodowej:
Dyplom magistra inżyniera automatyki i robotyki w 1999 roku na Wydziale Mechanicznym Politechniki Łódzkiej,
Dyplom doktora w 2008 roku.
Od roku 2000 zatrudniony w Katedrze Techniki Ogrzewczej i Wentylacyjnej, a potem w Instytucie Inżynierii Środowiska i Instalacji Budowlanych.
Obszar działalności naukowej:
W ramach pracy doktorskiej zajmował się problematyką łożyskowania maszyn i urządzeń w inżynierii środowiska. Obecnie zajmuje się badaniami dotyczącymi wpływu napięcia wstępnego układu łożysk kulkowych skośnych i łożysk stożkowych, celem których jest opracowanie i opublikowanie takiej metody doboru napięcia wstępnego układu łożysk skośnych, wskutek której byłoby osiągnięte zwiększenie sztywności łożyskowania bez znaczącego uszczerbku dla jego trwałości.
Dorobek naukowy:
Kaczor J., Raczyński A. : Analysis of bearing system of three-bearing shafts with respect to elastic shifts in bearings. The Archive of Mechanical Engineering Vol. LVII. 2010, 1. s. 97-105.
Bearings of a three-bearing shafts are usually treated as ideally rigid articulated supports. In literature the reactions of supports and bending moments of multi-bearing shafts are calculated taking into consideration only shaft elasticity. In fact also deformation is present in bearings, and it changes shaft bending line. The deformation thus influences distribution of bending moment and reaction of supports. It is the most important difference when considering two-bearing and three-bearing shafts. Moreover in most types of bearings a reactive bending moment is a response of bearing to unparallel position of inner bearing rings in relation to outer rings, that is to tilt angle. As a result, real loads of rolling elements differ from theoretical loads. The aim of the paper is to develop a method of calculating generalized` loads in rolling bearings of a three-bearing shaft taking into consideration shaft deformation, deformations in bearings and reactive moments of bearings caused by tilt angle.
Kaczor J.: Analysis of influence of dislocations in a bearing connection with bearing slackness on basic rating life of a bearing system of a statically undetermined shaft. The Archive of Mechanical Engineering. Vol. LVIII, 2011,3. Warszawa 2011. s. 291-303.
Commonly used computations of basic rating life of a bearing system are based on the ISO 281:1990 standard. These computations include dynamic load capacity of a given bearing, its effective load and average rotational speed, whereas they omit distribution of external load acting upon particular rolling parts depending among others on: -displacement in bearing (displacements in three directions and declination in two planes), -slackness in bearings. The aim of the presented theoretical research is solving a problem of fatigue life of a ball bearing taking into consideration displacement in bearing resulting from elasticity of a three-bearing shaft, elasticity of bearings and their internal slackness.
Kaczor J.: Influence of the shape of the ball bearings raceway on the load in the bearings. Tribologia Nr 5/2013 (251) „SIMPRESS” ISSN 0208-7774. 2013. s. 33-44.
The bearings of the three bearing shaft are usually regarded asideally stiff articulated supports. In technical literature, the shaft elasticity is the only factor taken into account when determining the reaction and bending moments of three bearing shafts. The elasticity of the bearings is not taken into consideration. In fact, the bearings experience deformation, which causes additional shaft deflection and has an impact on contact stresses in the bearings. These deformations depend on, among others, the osculation. The objective of this paper is to determine the effect of the osculation on the contact stress of the three bearing shaft, as well as on its durability.
Kaczor J.: The influence of clearances in ball bearings on work failure of three-bearing shaft. Tribologia Nr 5/2014 (257) „SIMPRESS” ISSN 0208-7774, s. 89-100.
Durabilitydeep groove ball bearings depends on factors (called attributes) design, technological and operational. Among the design features one of the most important is play in the bearings. Polish Norm shows five groups of looseness in the bearings, in which the play range from 0 to 105 microns. Manufacturersof rolling bearings they only play group, which has a bearing data, without giving the exact value of the slack. Aim of this study is to determine how it affects the play in the bearings to work three-bearing shafts, including elasticity and resilience three-bearing shafts.
Kaczor J., Raczynski A.: The effect of preload of angular contact ball bearings on durability of bearing system. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 2015. Vol. 229(6) 723-732.
Angular contact ball bearingsare commonly used in such situations when you need to reach high bearing stiffness. However, a significant stiffness increase can be achieved only through the introduction of preload to the angular contact bearings.The purpose of thispaper is to present a method for assessing the effect of preload of the angular contact ball bearings for their durability.
Kaczor J., Raczynski A.: The influence of location of the surface of load on the value of preolad in the system of angular contact ball bearings. Tribologia Nr 1/2016 (265) „SIMPRESS” ISSN 0208-7774. 2016 r. s. 21-33.
Angular contact ball bearings are commonly used when high stiffness of the bearing is needed. However, a significant stiffness increase can be achieved only through introducing preload (mounting tightness) to the system of angular ball bearings. The aim of the study is to determine how the location of a plane of a load influences the selection of preload in a system of angular contact ball bearings, and, in consequence, the durability of the bearing.
Kaczor J., Raczynski A.: The influence of preload on the work of angular contact ball bearings. The Archive of Mechanical Engineering. Vol. LXIII, 2016,3. Warszawa 2016. s. 319-336.
Optimum values of preload can be achieved in well-tried constructions and then applied in similar structures. For new structures, it is recommended to calculate the preload force and to test the correctness of calculation by means of experiments. In practice it may be necessary to introduce corrections, because not all real work parameters can be precisely known. Credibility of calculations depends, first of all, on the consistence between the assumptions concerning temperature conditions during work and elastic deformations of cooperating elements - first of all of a holder – and the real work conditions. The aim of the study is to determine how preload influences the work of a system of angular ball bearings, in relation to durability of bearing, moment of friction and rigidity of the bearing.
Kaczor J., Raczyński A.: The selection of preload in angular contact ball bearings according to the durability criterion. Tribologia 2018, Volume 277, No. 1, pp. 25-34, DOI: 10.5604/01.3001.0011.8284.
Regulation of preload of angular contact ball bearings is mentioned in specialist literature, but only as a practical activity carried out based on experience, still without selection methodology. At present there exists no widely accessible method of this load selection. Neither the literature on subject nor catalogues of bearings producers give recommendations for selection of this parameter, which is most often perceived intuitively. Still it is known that its wrong selection can have a catastrophic influence on durability of bearings. In consequence there exists a problem of accurate choice of preload (i.e. of such a preload that the durability of bearings will not be significantly decreased). The aim of the study is to determine the maximum preload in angular contact ball bearings by the criterion of durability, taking into account a shaft flexibility and flexibility of bearings. In order to determine a general influence of preload on fatigue life of bearings, numerous calculations were made for different locations of the plane of load
Kaczor J., Raczyński A.: The selection of preload in angular contact ball bearings according to the criterion of moment of friction.Tribologia 2018, Volume 277, No. 1, pp. 35-44, DOI: 10.5604/01.3001.0011.8286.
The preload can be expressed as a force or as a dislocation (distance). Depending on the regulation method, the preload is also indirectly connected with the moment of friction in a bearing. The objective of the paper is to determine a maximum preload in angular contact ball bearings, based on the moment of friction in a system of bearings.
Kaczor J: A metod of preload selection for a system of angular contact ball bearings due to the moment of friction. Tribologia 2019, Volume 283, No. 1, pp. 5-12, DOI: 10.5604/01.3001.0013.1429
Angular contact ball bearings are usually used in the situation when high stiffness of a bearing is demanded. Yet a significant stiffness improvement can be achieved only after introducing a preload (so-called assembly clamp) into a system of angular bearings. The aim of the research was to develop a method of preload selection for a system of angular contact ball bearings. As a result higher stiffness of the bearing without significant loss in its durability will be obtained.
Kaczor J.: The influence of preload in relation with load on a system of angular ball bearings. Tribologia 2019. Volume 284, No. 2, pp. 65-73, DOI: 10.5604/01.3001.0013.4151.
A proper preload has a decisive influence on the correct work of a system of bearings. The main benefits of preload application are the following: increasing the stiffness of a system of bearings, reducing noise during work, increasing precision of the shaft driving, compensation for the wear and settle processes during work, and thus assurance of a longer life of the system. The aim of the study is to determine how application of preload influences the operation of angular bearings, i.e. their durability, stiffness and friction. The influence of preload will be expressed in a relative way: through variations of ratios.
Kaczor J.: Analysis of the influence of shaft load on the value of acceptable preload in a system of angular ball bearings. Tribologia 2020. Volume 290, No. 2, pp. 25-35, DOI: 10.5604/01.3001.0014.3737.
In standard solutions reactions of the supports and bending moments in bearing shafts are calculated without taking into consideration the elasticity of the bearings themselves. They are treated as perfectly stiff supports of articulate character. Whereas, in reality majority of bearings do not fulfil conditions of being classified as joints, because angular tilt of inner bearing ring in relation to the outer one causes inner elastic deformations in elements of bearings and the resulting reaction moments. These moments have an impact on reactions of bearings. The aim of the research is to determine how shaft loading influences the value of preload, by using the criterion of durability of bearing and taking into consideration the elasticity of bearings.
Dorobek dydaktyczny:
Prowadzenie na kierunku Sieci i instalacje w inżynierii środowiska z przedmiotów:
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Termodynamika techniczna,
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Rysunek instalacyjny,
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Optymalizacja energetyczna instalacji przemysłowych,
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Nowoczesne systemy wentylacji i klimatyzacji.