6tXG\ on tKe emSt\inJ time of Jrain Karvester KoSSers

Abstract

Editors and Sections Genetics and Breeding ntro tionThe systems for emptying harvester grain hoppers consist of several consecutively operating augers located at a different angle ithin the hopper space igure 1 . By means of cover plates 1, located above the horizontal auger 2 the grain intake is controlled to prevent any blockage of the system. The e tent of the cover plates opening is controlled according to the type of grain, volumetric eight and its moisture level. hen the cover plates are half closed, the blockage of the system is practically impossible, but its flo rate decreases. These systems are ith a simple, easy to actuate and do not re uire special maintenance Cole, 2002 . The re uirement is to have high flo rate in order to empty the hopper for a short period of time and thus provide greater hourly and daily performance, especially hen unloading hoppers at a standstill Delchev and Trendafilov, 2002 . Usually, designers match the auger flo rate to the hopper volume, so that at 1 grain moisture the emptying to be done for 1. 2 min Isaacson, 197 .The flo rate of emptying systems, the re uired capacity of actuation and the percentage of damaged grain depend on a number of factors geometric parameters of augers, slope angle of grain transportation, type of grain, moisture, etc. It has been established that the auger slope angle has a significant effect on its flo rate, but almost no effect on grain damaging Hall, 1974 . In addition, by increasing the slope angle the re uired capacity for actuating the auger also increases and reaches its ma imum at an angle bet een 4 and 0 , and then it drops do n since the flo rate decreases. ith a vertical auger at an angle of 90 , the 2 1 e mail krasimir.trendafilov trakia uni.bg 1.: 1 -2 -3 -4 -292 capacity required for actuating is the same as in horizontal position but the flow rate is considerably lower (Midwest Plan Service, 1988). It has been found that dry grain damages (with low moisture) are minimum when using the maximum flow rate of the auger (Sands and Hall, 1971). The main characteristic of the systems for emptying harvester grain hoppers is their designed flow rate, which is given as а flow rate of the unloading auger in l/s. In fact, this flow rate is maximum possible and is reached at a nominal angle speed of the engine. This is the angle speed that drives all harvester mechanisms and systems at harvest. When unloading the grain hopper at a standstill and well-adjusted cover plates the designed flow rate of the system is practically used.It has been established that in Bulgaria the grain hopper unloading in 90% of the farms is done at a standstill (Delchev et al., 2016). In this case the operators, usually do not use the engine nominal engine revolutions, but lower ones. In that way, the designed flow rate of the emptying system is not reached, the unloading time increases and the grain harvester performance decreases. The designed flow rate cannot be reached either in the cases when cover plates 1 (Figure 1) are half-closed and not adjusted for the ...

Study and Analysis of the Structure of the Working Time of Combine Harvester for Harvesting of Wheat

“…The rest of the time is lost for moving the combine or the truck and positioning for unloading [2]. Because an average of 73% of the flow rate of the unloading auger is used, the unloading time is 43% greater than the theoretical [5]. The work of individual authors provides detailed information on the duration of separate operations in harvesting and mainly for unloading the grain hopper.…”