Patent ID: 8974006
Filing Date: 2015-03-10
Classification: B60K,E01C

Abstract:
1. A method of driving a working unit of a self-propelled civil engineering machine, the machine including: a frame having a direction of travel; a milling drum supported from the frame for working engagement with a ground surface, the milling drum having a drum axis; a first internal combustion drive engine arranged on the frame transversely to the direction of travel; and a second internal combustion drive engine arranged on the frame transversely to the direction of travel, the second internal combustion drive engine being substantially parallel to the first internal combustion drive engine and non-coaxial with the first internal combustion drive engine, the first and second engines being arranged next to one another in a plane located above the milling drum axis; the method comprising: (a) operating the first internal combustion drive engine to produce a first driving power; (b) operating the second internal combustion drive engine to produce a second driving power; and (c) adding together and transmitting the first and second driving powers to the milling drum with a belt drive system; and (d) setting a crankshaft angle of the first engine relative to a crankshaft angle of the second engine and thereby at least partially cancelling rotary oscillations produced by the first engine with rotary oscillations produced by the second engine.