Vibrating screening feeder and method of use

Abstract

A vibrating screen feed conveying apparatus for conveying and separating sticky “moisture laden bulk solids” which are sticky and wet flowing onto a vibrating screening feeder and into a hopper. The apparatus includes a bed on which material is conveyed, a longitudinal counterbalance supported on a plurality of isolation springs, a plurality of inclined drive springs extending between the bed and the longitudinal counterbalance, and a plurality of stabilizers for controlling movement of the drive springs along their central axes. A plurality of vibratory motors, each having rotatable eccentric weights are attached to the rear end of the longitudinal counterbalance. The eccentric weights rotate in phase with one another to vibrate the bed at a vibration frequency.

I claim: 
     
         1 . 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; and   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.   
     
     
         2 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of uniformly adjusting the vibration frequency of said bed by adjusting the rotational speed of each of said plurality of paired vibratory motors while operating at substantially the same rotational speed with respect to one another. 
     
     
         3 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of adjusting a rate of feed by adjusting an operating stroke and a frequency of said plurality of drive springs and said plurality of stabilizers. 
     
     
         4 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of rotating said first rotatable eccentric weight and said second rotatable eccentric weight in opposite directions relative to one another. 
     
     
         5 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of selecting a plurality of alternating current motors for said plurality of paired vibratory motors. 
     
     
         6 . The vibrating conveyor screening and feeding process of  claim 5 , including the step of adjusting said plurality of alternating current motors having an output shaft extending from a top end and a bottom end with an eccentric weights mounted thereon over a complete range of zero to maximum output. 
     
     
         7 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of controlling a rate of feed material on said vibrating conveyor screening feeder by monitoring the amps pulled by an apparatus being feed by said vibrating conveyor screening feeder and measuring the feedback to increase or decrease the rate of speed of said vibrating conveyor screening feeder by controlling the amps pulled by each one of said plurality of paired vibratory motors in accordance therewith. 
     
     
         8 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of mounting said plurality of vibratory motors mount to a selected end of said longitudinal counterbalance. 
     
     
         9 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of fixedly connecting said first end of said plurality of drive springs and said first end of said plurality of stabilizers at a selected angle to a plurality of downward extending abutments disposed on a bottom surface of said bed and mounting said second end of said plurality of drive springs and said second end of said plurality of stabilizers to said longitudinal counterbalance. 
     
     
         10 . The vibrating conveyor screen feeder of  claim 1 , wherein said plurality of paired vibratory motors have an output shaft extending from a top end and a bottom end with an eccentric weight mounted on each of said output shafts in mechanical time with one another. 
     
     
         11 . The vibrating conveyor screen feeder of  claim 1 , including a programmable motor control unit capable of controlling said plurality of paired vibratory motors synchronized with one another at a selected speed, and periodically changing said selected speed for a selected time interval by a selected amount. 
     
     
         12 . The vibrating screen feed process of  claim 1 , including the step of sub-resonant tuning said plurality of drive springs to drive harder under loaded conditions. 
     
     
         13 . The vibrating screening and feeding process of  claim 1 , wherein said plurality of isolations springs and said plurality of drive springs comprise steel coil springs and said plurality of drive springs are stiffer than said plurality of isolation springs. 
     
     
         14 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of operating said plurality of paired vibratory motors at an operating frequency below the resonance point of said drive springs. 
     
     
         15 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of adjusting vibration intensity during a timed cycle with an adjustable timer providing a momentary pulsing at a selected hertz for clearing said at least one screen. 
     
     
         16 . The vibrating conveyor screening and feeding process of  claim 15 , wherein said selected hertz is a momentary pulsing of at least 60 hertz for a time of from 3 to 5 seconds. 
     
     
         17 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of synchronizing the weight of said plurality of paired vibratory motors and driving said plurality of paired vibratory motors at a selected speed and periodically changing said selected speed for a selected time interval by a selected amount. 
     
     
         18 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of using said drive springs for producing a first portion of a load that opposes a vibratory motion and a plurality of said stabilizers for guiding the motion, and said plurality of paired vibratory motors for producing a remaining portion of the load that opposes said vibratory motion. 
     
     
         19 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of operating said vibrating conveyor screening feeder at a prescribed stroke at a selected distance over a selected frequency measured in cycles per minute whereby a rotational speed of said plurality of paired vibratory motors in revolutions per minute is the same as the operating frequency of said vibrating conveyor screening feeder. 
     
     
         20 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of selecting a range of from zero to maximum output adjustment of said plurality of paired vibratory motors with a vibratory stroke of 50 Hz for 25 seconds and a pulse stroke of at least 60 Hz from 3 to 5 seconds. 
     
     
         21 . The vibrating conveyor screening and feeding process of  claim 1 , including the step of forming equal acceleration in both directions of a back and forth movement of said vibratory stroke. 
     
     
         22 . The vibrating screen feed process of  claim 1  including the step of selecting a defined stroke angle which is perpendicular to an axial centerline of said plurality of stabilizers and in line with an axial centerline of said plurality of drive springs, whereby said vibrating screening feeder is dynamically counter-balanced. 
     
     
         23 . 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;   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 support, 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 said support, 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;   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; and   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.   
     
     
         24 . The vibrating conveyor screening and feeding process of  claim 23 , further including the step of providing said bed with at least one screen in flow communication with a pan extending the width and length of said bed, said bed fixedly connecting to said plurality of said drive springs and said plurality of stabilizers mounted at an angle to said support which comprises a longitudinal counterbalance. 
     
     
         25 . The vibrating conveyor screening and feeding process of  claim 24 , including the step of supporting said longitudinal counterbalance with a plurality of isolation springs extending upward from a base. 
     
     
         26 . The vibrating conveyor screening and feeding process of  claim 24 , including the step of mounting said plurality of vibratory motors mount to a selected end of said longitudinal counterbalance. 
     
     
         27 . The vibrating conveyor screening and feeding process of  claim 24 , including the step of fixedly connecting said first end of said plurality of drive springs and said first end of said plurality of stabilizers at a selected angle to a plurality of downward extending abutments disposed on a bottom surface of said bed and mounting said second end of said plurality of drive springs and said second end of said plurality of stabilizers to said longitudinal counterbalance. 
     
     
         28 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of uniformly adjusting the vibration frequency of said bed by electrically adjusting the rotational speed of each one of said plurality of paired vibratory motors while operating at substantially the same rotational speed with respect to one another. 
     
     
         29 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of rotating said first rotatable eccentric weight and said second rotatable eccentric weight in opposite directions relative to one another. 
     
     
         30 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of selecting a plurality of alternating current motors for said plurality of paired vibratory motors. 
     
     
         31 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of adjusting said plurality of alternating current motors having an output shaft extending from a top end and a bottom end with an eccentric weights mounted thereon in mechanical time with one another. 
     
     
         32 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of controlling a rate of feed material on said vibrating conveyor screening feeder by monitoring the amps pulled by an apparatus being feed by said vibrating conveyor screening feeder and measuring the feedback to increase or decrease the rate of speed of said vibrating conveyor screening feeder by controlling the amps pulled by said plurality of paired vibratory motors. 
     
     
         33 . The vibrating conveyor screen feeder of  claim 23 , including controlling said plurality of paired vibratory motors synchronized with one another at a selected speed, and periodically changing said selected speed for a selected time interval by a selected amount. 
     
     
         34 . The vibrating conveyor screen feeder of  claim 23 , including the step of producing a first portion of a load that opposes vibratory motion with said plurality of drive springs, guiding said vibratory motion with said plurality of stabilizers, and producing a remaining portion of said load opposing said vibratory motion with said plurality of paired vibratory motors. 
     
     
         35 . The vibrating screening and feeding process of  claim 25 , including the step of selecting said plurality of isolation springs and said plurality of drive springs from steel coil springs wherein said plurality of drive springs are stiffer than said plurality of isolation springs. 
     
     
         36 . The vibrating conveyor screening and feeding process of  claim 23  including the step of operating said plurality of paired vibratory motors at an operating frequency below the resonance point of said plurality of said drive springs. 
     
     
         37 . The vibrating conveyor screening and feeding process of  claim 23  including the step of adjusting vibration intensity during a timed cycle by adding a standard variable frequency combined with an adjustable timer providing a momentary pulsing at a selected hertz to said at least one screen. 
     
     
         38 . The vibrating conveyor screening and feeding process of  claim 37 , wherein said selected hertz is a momentary pulsing of at least 60 hertz for a time of from 3 to 5 seconds. 
     
     
         39 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of synchronizing a weight of said plurality of paired vibratory motors and driving said plurality of paired vibratory motors at a selected speed and periodically changing said selected speed for a selected time interval by a selected amount. 
     
     
         40 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of producing a vibratory stroke of 50 Hz for 25 seconds and an automatic momentary pulsing of at least 60 hertz of from 3 to 5 seconds. 
     
     
         41 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of operating said vibrating conveyor screening feeder at a prescribed stroke at a selected distance over a selected frequency measured in cycles per minute whereby a rotational speed of said plurality of paired vibratory motors in revolutions per minute is the same as the operating frequency of said vibrating conveyor screening feeder. 
     
     
         42 . The vibrating conveyor screening and feeding process of  claim 23 , including the step of forming equal acceleration in both directions of a back and forth movement of said vibratory stroke. 
     
     
         43 . The vibrating screen feed process of  claim 23 , including the step of selecting a defined stroke angle perpendicular to an axial centerline of said plurality of stabilizers and in line with an axial centerline of said plurality of drive springs, whereby said vibrating screening feeder is dynamically counter-balanced. 
     
     
         43 . The vibrating screen feed process of  claim 23 , including the step of sub-resonant tuning said plurality of drive springs to drive harder under loaded conditions.