Measurement of tractive effort at the drawbar of tractor in aggregate with mounted agricultural machine
Dynamometer test is used in scientific researches and in operation of tillage machines. It is necessary for completing of tractor units, for setting of rate of production and fuel consumption, and also for ensuring the control of technical condition of tractors and agricultural machines and correctness of their regulation. Under operating conditions, dynamometer test consists in determination of a horizontal component of tractive resistance of tillage machines. According to these data, it is possible to give the general comparative assessment of power consumption of various machines. There are methods of dynamometer test with the use of dynamometer frames, and also with the use of load cells, which embed into linkages and pins of the three-point hitch. All these methods have several disadvantages. Main of them is the use of several force sensors, which provides the lack of possibility of direct measurement of the total forces and raw errors of determination of the sought quantities. The aim of the research is to develop a device for dynamometer test of mounted agricultural machines, allowing to make the necessary measurements using one force-measuring sensor, without design changes of tractor and mounted machine. Presented dynamometer automatic coupler is made on the basis of two standard automatic couplers with a force measuring sensor mounted between them. Experimental studies showed the operability of the presented dynamometer automatic coupler. The proposed device is universal, it can be used with any tractor and any mounted agricultural machine and does not require design changes of tractor and agricultural machine. The application of one force measuring sensor enables the measurement with high precision.