Abstract: A torsional vibrating device is disclosed for operation as a two mass vibrating system consisting of a first mass having a generally circular work member and a spring mechanism connecting the first mass to the second mass excited by a motor driven eccentric weight or weights so that the second mass vibrates in a circular path having a circular component and a vertical component which will cause material on said work member to be conveyed in a circular direction. The spring member is unique in this combination. The entire system is isolated from the supporting means. This system has application for controlling the flow of bulk material from a hopper, screen or feeder or for elevating or lowering a material in a helical trough or for orientation of discrete particles or other applications depending on a properly designed work member.

Abstract: A vibratory device operable as a two mass vibrating system for driving a work member as used in feeders, screens, conveyors and the like, employs a motor driven eccentric weight exciter attached to one mass which is spring coupled to a second mass with the entire device being supported by isolator springs. The spring coupling is adjustable in a generally vertical plane to vary the direction of application of the exciter forces transmitted from the first mass to the second mass to fix this direction as conditions of use call for, the second mass being vibrated with the work member forming a part of such second mass to perform the work produced by the vibratory device in driving the work member. A D.C. brush or brushless motor is particularly useful to drive the exciter for driving relatively small work members to achieve ease of changing the rotative speed of the eccentric weight exciter as conditions dictate.