Patent ID: 7412818

Claim:
A rotor spinning machine comprising: a plurality of working stations, a bobbin supplying device disposed at a fixed position relative to the plurality of working stations, the bobbin supplying device including a conveyance device extending along the working stations for delivering bobbins to the individual working stations in a predetermined direction of bobbin conveyance, at least two service units arranged to travel along the working stations for transferring a bobbin from the conveyance device to an individual working station when in need of a new bobbin, each service unit adapted for transmitting a bobbin request to the bobbin supplying device for delivery of a bobbin along the conveyance device to an individual working station, and a control device for controlling the service units, the control device including an arrangement, operative when a first one of the service units transmits a bobbin request to the bobbin supplying device for a working station disposed more remotely from the fixed position of the bobbin supplying device in relation to the direction of bobbin conveyance than the disposition of a second one of the service units, to suppress a subsequent bobbin request from the second service unit for a working station disposed more closely to the bobbin supplying device in relation to the direction of bobbin conveyance until the bobbin request from the first service unit has been fulfilled, thereby to prevent the second service unit from taking from the conveyance device the bobbin being delivered to the first service unit.