A Simplified Approach Towards Draft Control in Hydraulic Machineries for Component/Cost Reduction 2019-26-0102
Draft control is a mechanism primarily provided in Tractors to maintain the penetration of its rear attachment (plough) in ground, such that there isn’t a condition of overload on the machine, i.e., the operation remains under control parameters. With time, the concept was introduced in excavators too, for controlling the cutting-edge penetration of bucket in the ground.
The technologies currently employed by global construction equipment manufacturers involve complex electronic components like John Deere is using Nano-sensors and ECU, KOMATSU uses stroke sensors in hydraulic cylinders to map real time position of the bucket and hence control the penetration depth, etc. The output of most of these systems are driver warnings, on the dash panel. Even if the system is automated, it involves additional components to automate the draft control.
The concept proposed in this paper not only reduce the number of components, but makes the system more reliable shifting from electronic sensing to mechanical sensing. Besides, the system is inherently automated without any additional cost/components.
The system uses a pressure relief valve to sense the pressure in the acting cylinder, like in excavation, the major work is done by the cylinder that controls the ARM. The relief valve acts as a pilot operation line to Control Boom input. The setting a pressure relief valve is made electronic with a knob provided in cabin with different modes for different terrains like soft soil, hard soil, debris, dust, etc. This allows the hydraulic pump to run under control conditions at all times, thus optimizing the efficiency of the complete system, reducing the cost of operation.
Sukrit Mittal, Rishabh Singh
Mahindra Mahindra, Ltd.
Symposium on International Automotive Technology 2019