presence or absence of textile fibers carried on the conveyor 30 fig3 illustrates schematically the control system for selectively operating the conveyor 30 through its motor 68 the details of the electrical circuitry included in this control system forming no part of the present invention it will be noted in fig3 that the conveyor motor 68 is controlled by the aforesaid operation of the weigh pans 14 and the photocell 72 and by a time delay control 76 and a demand switch 74 which is associated with apparatus such as a bale press not shown downstream of the receiver unit 28 to indicate when fibers are required or not required from the receiver unit 28 the relationship of the control components shown schematically in fig3 will become apparent in connection with the following description of the operation of the present invention in the normal operation of the disclosed embodiment of the present invention the entire apparatus will be turned on manually by the operating personnel using conventional manually operated electrical switches the downstream bale press not shown will likewise be started up through its own control system this initial start up places the drive motors 62 66 and 70 for the belt conveyor 16 the blower 24 and the beater roll 50 respectively in continuous operation so long as the blending apparatus is turned on this initial start up also makes power available to the feeders 10 and weigh pans 14 and to the conveyors 30 and 46 and to the various controls therefor assuming that the normal operational supply of fibers is being supplied to the feeders 10 either manually or automatically as is common in the art and that the weigh.