A CONTROL COUPLING FOR A DELIMBING AND CUTTING APPARATUS

摘要

A control coupling for a delimbing and cutting apparatus, provided for feedi ng means and for changing their feeding speed, and compirising at least two fee d motors (1, 2) driven by a pressurized medium, each of the motors being intended to drive a feeding means which is intended to be placed against a tree trunk and to feed the tree trunk through said apparatus, a first channe l (4), via which the pressurized medium can be supplied to the first feed moto r (1) and alternatively returned therefrom, and a second channel (5), via whic h the pressurized medium can be returned from the second feed motor (2) and alternatively supplied to the same. Said feed motors are multi-capacity motors, wherein each motor (1, 2) has at least a first rotational capacity (1a, 2a) and at least a second rotational capacity (1b, 2b) as well as a fir st and a second basic connection for each capacity. The first basic connections of each motor (1, 2) are coupled together as a first connection (R1, R2), an d the second basic connections of each motor (1, 2) constitute a second connection (A1, A2) and a third connection (B1, B2), which are separate. The control coupling further comprises first valve means for coupling at least t wo different feeding speeds in operation, wherein the valve means are arranged to couple desired connections (A1, A2, B1, B2, R1, R2) and channellings (4, 5) together.