Performance Characteristics of a Tillage Machine with Active-Passive Components

An experimental tillage machine that combines active, rotary-powered tillage elements with conventional passive chisel tines was field tested. Negative draught created by the active elements was used to contribute to the passive tine draught requirements. A tillage machine of this configuration could improve power transmission efficiency for tillage, reduce wheel slip, allow use of lighter tractors and allow tillage to take place in more difficult tractive conditions. Field tests of the experimental active-passive tillage machine were conducted to investigate the effects of velocity ratio (ratio of rotor tip velocity to forward velocity), forward speed and active/passive depth ratio (ratio of depth of active elements to depth of passive elements) on machine performance. The draught of the active-passive tillage machine was at least 50% lower in all cases than a similar machine using purely passive tillage tools. The active-passive tillage machine reduced the gross specific fuel consumption by a maximum of 27% and net fuel consumption by a maximum of 36%. Wheel slip was reduced by at least 55% with the active-passive tillage machine. The active-passive tillage machine was able to reduce the draught, fuel consumption, wheel slip and engine flywheel power requirements compared to a similar passive tillage tool when the velocity ratio was less than 2·0. The velocity ratio was the most influential factor affecting the operating characteristics. Copyright 1993, 1999 Academic Press