A vibratory conveyor compri sing: (a) a frame; (b) a first conveying member mounted on said frame and having a conveying surface; (c) a source of vibratory force for providing vibratory movement to said conveying member; wherein said first conveying member is pivotally connected to a counterweighting member by a plurality of rocker arms, each rocker arm being pivotally connected to said first conveying member at a first axis of rotation, to said counterweighting member at a second axis of rotation and being biased for oscillating motion about a third axis of rotation, wherein each said rocker arm is biased for oscillating motion about said third axes of rotation by being mounted on said frame for oscillating motion about the central axis a first end of a torsion bar to which it is fixed, wherein said source of vibratory force wherein said source of vibratory force is springless and comprises a motor, a rotatable eccentric shaft and two drive arms (226, 227); characterized in that the second end of each said torsion bar is fixed to the frame; wherein the motor drives a sheave through a drive belt, wherein the sheave is mounted on the rotatable eccentric shaft, which rotates in a bearing, wherein a balancing weight is attached to the eccentric shaft by a hub and a first lock assembly in order to assist in balancing the drive system by countering the offset of the eccentric shaft, wherein each drive arm (226, 227) is journaled at one end thereof on the eccentric shaft for rotation on a respective bearing and each pivotally connected at the other end thereof to one end of a respective torsion arm, wherein each torsion arm is locked at its upper end on a respective torsion bar adjacent the first end of said torsion bar by a respective second lock assembly adjacent a respective flange in which the end of said torsion bar is free to rotate in a respective bushing, and wherein the other end of said torsion bar is locked in the central axis of a respective rocker arm by a respective third lock assembly to transmit vibratory motion to said rocker arm. (a) a frame; (b) a first conveying member mounted on said frame and having a conveying surface; (c) a source of vibratory force for providing vibratory movement to said conveying member; wherein said first conveying member is pivotally connected to a counterweighting member by a plurality of rocker arms, each rocker arm being pivotally connected to said first conveying member at a first axis of rotation, to said counterweighting member at a second axis of rotation and being biased for oscillating motion about a third axis of rotation, wherein each said rocker arm is biased for oscillating motion about said third axes of rotation by being mounted on said frame for oscillating motion about the central axis a first end of a torsion bar to which it is fixed, wherein said source of vibratory force wherein said source of vibratory force is springless and comprises a motor, a rotatable eccentric shaft and two drive arms (226, 227); characterized in that the second end of each said torsion bar is fixed to the frame; wherein the motor drives a sheave through a drive belt, wherein the sheave is mounted on the rotatable eccentric shaft, which rotates in a bearing, wherein a balancing weight is attached to the eccentric shaft by a hub and a first lock assembly in order to assist in balancing the drive system by countering the offset of the eccentric shaft, wherein each drive arm (226, 227) is journaled at one end thereof on the eccentric shaft for rotation on a respective bearing and each pivotally connected at the other end thereof to one end of a respective torsion arm, wherein each torsion arm is locked at its upper end on a respective torsion bar adjacent the first end of said torsion bar by a respective second lock assembly adjacent a respective flange in which the end of said torsion bar is free to rotate in a respective bushing, and wherein the other end of said torsion bar is locked in the central axis of a respective rocker arm by a respective third lock assembly to transmit vibratory motion to said rocker arm.