Vibrating screening feeder and method of use

A vibrating conveyor screening and feeding process including the steps of:

• providing a bed having an inlet end and an outlet end on which material is adapted to be conveyed in a direction, said bed having a vibrating screen housing including at least one screen in flow communication with a pan extending the width and length of said bed;
• providing a plurality of drive springs, each one of said plurality of drive springs having a first end attached to said bed and a second end attached to a longitudinal counterbalance, each one of said plurality of drive springs adapted to compress and extend along a line of stroke;
• providing a plurality of stabilizers, each one of said plurality of stabilizers having a first end attached to said bed and a second end attached to a longitudinal counterbalance, each one of said plurality of stabilizers being more rigid in a direction transverse to said line of stroke than in a direction of said line of stroke;
• fixedly connecting said bed to said plurality of said drive springs and said plurality of stabilizers at an angle to said longitudinal counterbalance supporting said longitudinal counterbalance with a plurality of isolation springs extending upward from a base;
• providing a plurality of paired vibratory motors including at least a first vibratory motor having a first rotatable eccentric weight adapted to rotate about a first axis and a second vibratory motor having a second rotatable eccentric weight adapted to rotate about a second axis, said first axis being located substantially in a first plane and said second axis being located substantially in a second plane, said second plane being non-coplanar with said first plane, said first axis being spaced apart from said second axis along the direction the material is conveyed, said first rotatable eccentric weight and said second rotatable eccentric weight are free-wheeling with respect to one another, said first vibratory motor and said second vibratory motor are adapted to operate at substantially the same operating speed and to provide an output force generally perpendicular to its axis of rotation, said first rotatable eccentric weight and said second rotatable eccentric weight are adapted to accumulatively synchronize with one another without being rotationally coupled to one another such that the combined resulting output force of said first rotatable eccentric weight is parallel to a line of stroke and a combined resulting output force of said second rotatable eccentric weight;
• operating said first vibratory motor and said second vibratory motor to rotate said first rotatable eccentric weight and said second rotatable eccentric weight, such that said first rotatable eccentric weight and said second rotatable eccentric weight accumulatively synchronize and accumulatively add their output forces and their respective power outputs and thereby vibrate said bed along said line of stroke at a vibration frequency;
• operating said first vibratory motor and said second vibratory motor at substantially the same selected operating speed which approaches being equal to, or is less than, the natural frequency of said plurality of drive springs which are vibrating said bed;
• using a programmable motor control unit providing a standard variable frequency combined with an adjustable timer creating a vibratory stroke of a selected first hertz rate for a selected first time and an automatic momentary pulsing of at a selected second higher hertz rate for a selected second shorter time enabling a full zero to maximum output adjustment.