Scientific Papers Series B Horticulture

Scientific Papers. Series B, Horticulture. Vol. LVII, 2013Print ISSN 2285-5653, CD-ROM ISSN 2285-5661, Online ISSN 2286-1580, ISSN-L 2285-5653KINEMATICS AND OPERATION PROCESS OF THE COMPLEXAGGREGATE USED TO PREPARE THE GERMINATIVE BED INVEGETABLE FARMINGConstantin VLAD 1 , Gheorghe BRTUCU 21 Research and Development Station for Vegetables Growing, 23 Mesteacanului Street, 120024,Buzau, Romania2 Transilvania University, 29 Eroilor Avenue, 500036, Brasov, RomaniaAbstractCorresponding author email: vlad.constantin44@yahoo.comPreparing the germination bed represents an essential work for growing and developing plants in vegetable farming.The machinery used can have a positive or negative influence on improving or degrading the soil’s physio-mechaniccharacteristics and on the quality of the work, therefore choosing them requires a lot of attention. These aspects are aresults of studying the kinematics and work process of the complex aggregate that is used during this stage.Key words: soil, germinative bed preparation, complex aggregate, kinematics, work process.INTRODUCTIONModeling the soil consists of a set of activitiesperformed with the purpose of improve thesoil’s physical, chemical and biological properties.During these activities the soil is overturned,aerated, mixed, crumbled, leveled, pressed andmodeled. Soil activities can be basic activitiesand germinative bed preparation activities.During the germinative bed preparation, thesoil is aerated up to the seeding or plantingdepth, in order for the soil to provide therequired pedoclimatic conditions for the plantsto develop, during the seeding and sproutingstages.The complex aggregates are machines that areused for preparing the germinative bed.The working organs that are shaped like bladeswith variable size are mounted on parallel barscalled blade-bearing bars. These bars are givenan oscillating motion from the tractor’s poweroutlet. They move on a plane perpendicular tothe machinery’s movement direction. Themechanism powering the bars transforms therotation movement into translational-oscillatormovement.MATERIALS AND METHODSThis piece of work will determine and study thetrajectory of the F(x F ,y F ,z F ) point, the top of the127lateral blade on the studied complex aggregate’sblade-bearing bar.The mechanism powering the blade-bearing baris presented in figure 1.a. This case presents acrank-rod mechanism featuring a crankshaft.The running element is the AB crank, while theled element is represented by the BC bar. Theblade-bearing bar executes the translationaloscillatormovement (Caproiu St., 1982,Naghiu L., 2003, Pásztor J and Bratucu Gh.,2008, Sztachó-Pekáry I. et al., 2007). Thechosen frame of reference, xGz, is a mobilesystem which moves at a constant speedreported to a stationary system, according tofigure 1.b.Figure 1. 1. a - Kinematics of a point from the complexaggregate blade-bearing bar, the running mechanism; b -mobile and stationary referenceThe F(x F ,y F ,z F ) point’s coordinates aredetermined using the coordinates of points A,