Possible Ways of Reducing the Number of Gears in Universal Gear Units

This paper analyzes possibilities of reducing the number of necessary gears in the family of universal motor gear reducers with helical gears, since both the production and storage of a large number of different gears cost a lot and impose a great burden for any gear manufacturer, as it can be seen from literature [1,2] that focuses on this problem. The paper particularly emphasizes the necessity of narrowing down the assortment of gear reducers and the possibility of changing the design solution between the pinion and the electric motor as they represent the basic possibilities for reducing the number of necessary gears. The paper also points out the need for a special selection of preferred gear ratios and corresponding gears as one of the possibilities for reducing the total number of gears. This can certainly result in faster delivery of a gearbox with the preferred gear ratio

Possible Ways of Reducing the Number of Gears in Universal Gear Units

This paper analyzes possibilities of reducing the number of necessary gears in the family of universal motor gear reducers with helical gears, since both the production and storage of a large number of different gears cost a lot and impose a great burden for any gear manufacturer, as it can be seen from literature [1,2] that focuses on this problem. The paper particularly emphasizes the necessity of narrowing down the assortment of gear reducers and the possibility of changing the design solution between the pinion and the electric motor as they represent the basic possibilities for reducing the number of necessary gears. The paper also points out the need for a special selection of preferred gear ratios and corresponding gears as one of the possibilities for reducing the total number of gears. This can certainly result in faster delivery of a gearbox with the preferred gear ratio

Physico-chemical characterization and anti- microbial activity of copper(II) complexes with 2-amino and 2-methylbenzimidazole derivatives

Copper(II) chloride, in warm ethanolic solution, reacted with 2-amino and 2-methylbenzimidazole derivatives to give complexes of the formula CuL2Cl2·nH2O, where L=1-benzyl-2-aminobenzimidazole 1-(4-methylbenzyl)-2-aminobenzimidazole, 1-benzyl-2-methylbenzimidazole and 1-(4-methylbenzyl)-2-methylbenzimidazole( n=1 or 2). The complexes were characterized by elemental analysis of the metal, molar conductivity magnetic susceptibility measurements and IR spectra. The molar conductivities of copper(II)complexes in dimethyl formamide (DMF) corresponding to a 1:1 type of electrolyte indicate that in all the complexes one of the coordinated chloride ions has been replaced by DMF molecule. The room temperature effective magnetic moments and IR data of the complexes suggest that all Cu(II) complexes have a tetrahedral configuration, which is realized by participation of the pyridine nitrogen of two organic ligand molecules and two chloride anions. The antimicrobial activity of the ligands and their complexes against Pseudomonas aeruginosa, Bacillus sp. Staphylococcus aureus, Sarcina lutea and Saccharomyces cerevisiae was investigated. The effect of copper complexation on the ligand antimicrobial activity is discussed

Analysis of Conceptual Solutions of Universal Helical Geared Reducers

Geared reducers are mechanisms designed to reduce the number of revolutions using geared elements and nowadays they present one of the most commonly used types of mechanical transmissions in mechanical engineering. Due to the different shapes of geared elements, there are different types of geared transmissions: helical, bevel, worm, special and combined transmissions.  This paper analyses only helical geared transmissions, since there is a great extent of whole this matter. Helical transmissions are analysed only with external helical gearing, since internal geared pairs represent a special and very large group of gears. Within the external helical geared transmissions, only torque transmissions are analysed, while the transmissions of motion are not analysed and they represent another large group of transmissions. Only universal gear reducers with axial, or almost-axial, parallel shafts are considered (two-stage and three-stage transmissions). Although, single-stage gear reducer produced with parallel shafts are not considered by the paper in order to reduce the area of researching. Gear reducers are most commonly delivered to customer with electric motor, known as motor geared reducer, and they are studied here extensively. Gear reducer can be also delivered without motor, only with input shaft. The basic aim of this paper is to present all characteristics and specificities of motor geared reducer in one place

ANALYSIS OF BUYING HABITS - WINE SEGMENT

On a market with high supply offer segmentation cares extremely high importance. Wine is characterized as highly complex product and possibility of segmentation is extremely large. To insure detailed analysis it is essential to take in count all starting points of segmentation. Demographic factor can help with the analysis but wine as a product demands as specific approach as possible to ensure relevant conclusion. Wine promotion and market communication without detailed analysis based on a market segmentation cannot give any reliability for a success. Market acknowledges high segment of bought buyers profiles and product offers. To meet bought wishes communicating with buyers is essential

Selecting the Size of the Universal Reducer, Taking into Account its Thermal Load Capacity

Universal helical gear motors are among mechanisms that operate with a very high efficiency (about 0.98 per gear pair) [1, 2] and thus their thermal power capacity has not received enough attention, even in the cases when they overheat (usually at higher ambient temperature and high power motors). Therefore, it is necessary to define the thermal capacity in the catalogues of the speed reducer with a solid input shaft, as it is done by worm and helical-worm gear units which operate with much lower efficiency. Some manufacturers [3] pay necessary attention to this factor and thus enable the proper selection of gear reducers; this means they have prepared certain procedures to be undertaken if such occasion occurs, in order to overcome possible problems that may arise due to overheating the gear reducer. With this approach in the universal gear unit selection, some positive benefits can be surely achieved in the market of gear reducers, and that should not be ignored

INFLUENCE OF THE TEETH NUMBER ON THE GEAR MODULE VALUE AND LOAD CAPACITY OF GEAR PAIR IN UNIVERSAL HELICAL GEAR DRIVES

The basic parameters of the universal gear drives, except the axis height, are not defined by the standard, so the manufacturers of universal gear reducers can define them in their way. Most of the manufacturers followed the parameter values of universal gear reducers of leading world producers in order to ensure their interchangeability and the better positioning of their gear units at the market. This paper deals with the analysis of the influence of the gear pair teeth number on the size of the module, as well as on the load carrying capacity of single-stage universal gear units. For defined gear ratio values, different combinations of teeth number of pinion and driven gear were selected. Further, it was made calculation of the basic geometric dimensions of the gear pair, as well as the load capacity

Causes Analyse of Breakages of Foundation Screws

The paper deals with problematic of gear units and machine foundating and consequences that occur by foundation screws releasing. Namely, reliable operating of gear units, as well as other stationary machines, requires properly foundating. However, after certain period of time, relaxation of screw material, self-untightening of nuts and looseness of foundation screws influence on reducing the force of preload screw tightening and unequal load distribution. This unequal load distribution causes unequal deformations, which generate occuring vibrations. In extreme cases, breakages of screws and heavier accidents of systems driven by that gear units or machines can happen. With this paper authors want to indicate influence of deterioration degree on its load capacity