In article influence of smoothing of loading on a drive of a combine by increase in sliding of the asynchronous engine at dynamic properties of transmission is shown. The increase dempherated reduces factor of electromechanical communication, however this reduction slightly and does not lead to appreciable increase in dynamic forces in transmission.

Mine tests of electric drives of mining machines do not give values of energy parameters ncosp, determining the thermal states of electric motors ...

Asynchronous electric motors of mining combines work in conditions of sharply variable loads, which parameters can be written off only by methods of random functions ...

There is no consensus on the optimal dynamic parameters of electric motors used to drive coal and tunnelling combines. It is known that the operating mode graphs of these machines are characterised by extreme irregularity and obey only probabilistic laws. ...

The increase in labour productivity in mines and the improvement of miners' working conditions have led to the widespread implementation of mining complexes with coal-cutting machines. To ensure high operational efficiency under various conditions, coal-cutting machines must incorporate regulation of both feed and cutting speeds. ...

Methods of calculating the performance of mining machines, associated with the use of energy characteristic and motor characteristic , have a number of significant disadvantages. Firstly, they do not take into account the significant load irregularity arising from random factors (variability of cutting resistance, feed irregularity, finite number of cutters, etc.). Secondly, the energy characteristic does not provide information for predicting instantaneous values of maximum loads, which may be the cause of motor overturning. Thirdly, it does not take into account the additional heating of the motor during operation with reduced voltage, which is not uncommon in the conditions of district electric networks.

Studies of friction-pulsating feed mechanism (in KMP-2 cutting machine) and hydraulic mechanism of volumetric type (in Ural-33 cutting machine) with rigid mechanical characteristics have shown that the feed speed at work in the face changes unevenly. This is explained by the unevenness of the process of destruction of the mineral, as well as the presence of a flexible rope in the feed drive ...

At Slantsy plant in 1965 there was carried out an experimental notching on the upper part of the limestone “slab” layer, where there is a 0,04 m thick interlayer of clay shale with lower strength. At the total height of the cutting slot of 115-120 mm, the destroyed part of the limestone was 75-80 mm, and 40 mm were in the clay shale interlayer. The cutting was made by the Ural-33 cutting machine mounted on skids above the scraper conveyor, with a bar length of 2 g and an unauthorized seven-line chain. The useful depth of the cut was 1.7 m. The machine was operated at a reduced cutting speed (1.6 m/sec) with I-80 cutters, whose back angle was increased from 5 to 15°.

Objectives of mine testing. In mine tests of downhole machines it is necessary to determine the design and operational characteristics of operation in given mining and geological conditions, rational mode of operation, stability of the machine, its productivity, the influence of the area network on the machine operation. To establish these characteristics it is necessary to fix instantaneous and average values of the following values ...

Failure of windings of electric motors of mining machines in most cases occurs due to the discrepancy between the actual thermal loads to the passport data of the electric motor. According to the data of the Department of Electrical Equipment of Mining Enterprises of the Leningrad Mining Institute, 80% of the failed motors of the combine “Intaugol” had damage to the windings ...