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.

1 . A vibrating screen feeder unit comprising:
 a generally rectangular fixed base with a plurality of upward extending support coil springs, said support coil springs fixedly attach to a top surface of said fixed base and fixedly attached to a bottom surface of a generally rectangular intermediate base, said intermediate base having at least two rows of alternating large and small triangular abutments extending upward therefrom, said large triangular abutments having a first side forming about a forty-five degree angle with a top surface of said fixed base, said first side of said large triangular abutment having a drive coil spring extending upward therefrom at about a forty-five degree angle with a top surface of said fixed base member, said small triangular abutments having a second side forming about a forty-five degree angle with a top surface of said fixed base, said second side of said small triangular abutment having two spaced apart leaf spring rockers extending upward at about a forty-five degree angle with a top surface of said fixed base, said first side of said large abutment facing toward said second side of said small abutment;   a generally rectangular vibrating screen housing having at least two rows of downward extending trapezoidal abutments on a bottom surface thereof, said trapezoidal abutments fixedly connected on a third side to free ends of said upward extending drive coils and on a fourth side to free ends of said upward extending leaf springs, said vibrating screen housing having at least one screen, an input hopper and at least two output apertures formed therein;   said vibrating screen housing having a plurality of single or 3 phase electrically adjustable alternating current motors mounted at one end thereof, said motors having output shafts extending from top and bottom ends with eccentric weights mounted on said shafts in mechanical time with one another said motors fully electrically adjustable over the complete range of zero to maximum output;   a vibration drive isolation assembly for vibrating said vibrating screening unit;   said vibration drive isolation assembly including at least two parallel longitudinal counterbalance beams supported on a plurality of isolation drive springs distributed across the width of said vibrating screening unit; at least one vibratory drive motor installed on said longitudinal counterbalance member;   said vibration drive isolation assembly includes a variable speed motor controller for adjusting vibration intensity;   said variable speed motor controller being operatively arranged for dynamically adjusting vibration intensity during a timed cycle;   
       said timed cycle includes an electrical control enabling a full zero to maximum output adjustment by means of adding a standard variable frequency (VFD) combined with adjustable timers so that a vibratory stroke required screening has an automatic capability of a momentary “pulsing” to 60 hertz (or higher) for a brief time of usually 3 to 5 seconds, which generates a “spurt” or “pulse” to the entire screening body for clearing screen media of a lump or a particle stuck in a screen opening or to break free accumulated layers of adhesive and cohesive particles that try to “stick” or adhere to the surface of a screening media and a passed “unders” collecting pan therebelow;
 said input hopper includes a vibratory motor; and 
 a programmable motor control unit driving said motors with said weights synchronized with one another and capable of driving said motors at a selected speed and of periodically changing said speed for a selected time interval by a selected amount. 
 
     
     
         2 . A vibrating screen feeder unit consisting of:
 a generally rectangular fixed base with a plurality of upward extending support coil springs, said support coil springs fixedly attach to a top surface of said fixed base and fixedly attached to a bottom surface of a generally rectangular intermediate base, said intermediate base having at least two rows of alternating large and small triangular abutments extending upward therefrom, said large triangular abutments having a first side forming about a forty-five degree angle with a top surface of said fixed base, said first side of said large triangular abutment having a drive coil spring extending upward therefrom at about a forty-five degree angle with a top surface of said fixed base member, said small triangular abutments having a second side forming about a forty-five degree angle with a top surface of said fixed base, said second side of said small triangular abutment having two spaced apart leaf spring rockers extending upward at about a forty-five degree angle with a top surface of said fixed base, said first side of said large abutment facing toward said second side of said small abutment;   a generally rectangular vibrating screen housing having at least two rows of downward extending trapezoidal abutments on a bottom surface thereof, said trapezoidal abutments fixedly connected on a third side to free ends of said upward extending drive coils and on a fourth side to free ends of said upward extending leaf springs, said vibrating screen housing having at least one screen, an input hopper and at least two output apertures formed therein;   said vibrating screen housing having a plurality of single or 3 phase electrically adjustable alternating current motors mounted at one end thereof, said motors having output shafts extending from top and bottom ends with eccentric weights mounted on said shafts in mechanical time with one another;   a vibration drive isolation assembly for vibrating said vibrating screening unit;   said vibration drive isolation assembly including at least two parallel longitudinal counterbalance beams supported on a plurality of isolation drive springs distributed across the width of said vibrating screening unit; at least one vibratory drive motor installed on said longitudinal counterbalance member;   said vibration drive isolation assembly includes a variable speed motor controller for adjusting vibration intensity;   said variable speed motor controller being operatively arranged for dynamically adjusting vibration intensity during a timed cycle;   
       said timed cycle includes an electrical control enabling a full zero to maximum output adjustment by means of adding a standard variable frequency (VFD) combined with adjustable timers so that a vibratory stroke required screening has an automatic capability of a momentary “pulsing” to 60 hertz (or higher) for a brief time of usually 3 to 5 seconds, which generates a “spurt” or “pulse” to the entire screening body for clearing screen media of a lump or a particle stuck in a screen opening or to break free accumulated layers of adhesive and cohesive particles that try to “stick” or adhere to the surface of a screening media and a passed “unders” collecting pan therebelow;
 said input hopper includes a vibratory motor; and 
 a programmable motor control unit driving said motors with said weights synchronized with one another and capable of driving said motors at a selected speed and of periodically changing said speed for a selected time interval by a selected amount. 
 
     
     
         3 . A method of screening aggregate using a vibrating screen unit including a fixed base unit supporting an intermediate base with connecting vertical support coil springs, and a vibrating screen and housing rotatably connected to said intermediate base by drive coil springs and leaf spring rockers driven by drive motors with eccentric weights attached to said intermediate base, comprising the steps of:
 a) providing said vibrating screen unit comprising:   a generally rectangular fixed base with a plurality of upward extending support coil springs, said support coil springs fixedly attach to a top surface of said fixed base and fixedly attached to a bottom surface of a generally rectangular intermediate base, said intermediate base having at least two rows of alternating large and small triangular abutments extending upward therefrom, said large triangular abutments having a first side forming about a forty-five degree angle with a top surface of said fixed base, said first side of said large triangular abutment having a drive coil spring extending upward therefrom at about a forty-five degree angle with a top surface of said fixed base member, said small triangular abutments having a second side forming about a forty-five degree angle with a top surface of said fixed base, said second side of said small triangular abutment having two spaced apart leaf spring rockers extending upward at about a forty-five degree angle with a top surface of said fixed base, said first side of said large abutment facing toward said second side of said small abutment;   a generally rectangular vibrating screen housing having at least two rows of downward extending trapezoidal abutments on a bottom surface thereof, said trapezoidal abutments fixedly connected on a third side to free ends of said upward extending drive coils and on a fourth side to free ends of said upward extending leaf springs, said vibrating screen housing having at least one screen, an input hopper and at least two output apertures formed therein;   said vibrating screen housing having a plurality of single or 3 phase electrically adjustable alternating current motors mounted at one end thereof, said motors having output shafts extending from top and bottom ends with eccentric weights mounted on said shafts in mechanical time with one another said motors fully electrically adjustable over the complete range of zero to maximum output;   a vibration drive isolation assembly for vibrating said vibrating screening unit;   said vibration drive isolation assembly including at least two parallel longitudinal counterbalance beams supported on a plurality of isolation drive springs distributed across the width of said vibrating screening unit; at least one vibratory drive motor installed on said longitudinal counterbalance member;   said vibration drive isolation assembly includes a variable speed motor controller for adjusting vibration intensity;   said variable speed motor controller being operatively arranged for dynamically adjusting vibration intensity during a timed cycle;   
       said timed cycle includes an electrical control enabling a full zero to maximum output adjustment by means of adding a standard variable frequency (VFD) combined with adjustable timers so that a vibratory stroke required screening has an automatic capability of a momentary “pulsing” to 60 hertz (or higher) for a brief time of usually 3 to 5 seconds, which generates a “spurt” or “pulse” to the entire screening body for clearing screen media of a lump or a particle stuck in a screen opening or to break free accumulated layers of adhesive and cohesive particles that try to “stick” or adhere to the surface of a screening media and a passed “unders” collecting pan therebelow;
 said input hopper includes a vibratory motor; and 
 a programmable motor control unit driving said motors with said weights synchronized with one another and capable of driving said motors at a selected speed and of periodically changing said speed for a selected time interval by a selected amount; 
 b) inputting aggregate material to an input hopper at an input end of said vibrating screen; 
 collecting and using screened aggregate; 
 c) collecting coarse aggregate; 
 d) reprocessing coarse aggregate and recycling reprocessed aggregate into said input hopper; and 
 e) setting programmable drive motor controller for proper cycling between normal speed and a slightly higher speed for selected time periods to prevent clogging of vibrating screen. 
 
     
     
         4 . A vibrating screening feeder for feeding biomass and other fuels comprising:
 a hopper containing a biomass having particles of various sizes, said hopper including a down chute;   a vibrating screening unit;   said hopper including a outlet interfacing with an inlet chute of said vibrating screening unit, said inlet chute including a baffle of 30 to 60 degrees for spreading said biomass particles across a selected width of a feed plate of said vibrating screening unit;   a vibration drive isolation assembly for vibrating said vibrating screening unit;   said vibration drive isolation assembly including a longitudinally extending longitudinal counterbalance member; a plurality of drive springs supported by said longitudinal counterbalance member with said drive springs being distributed across at least the width of said vibrating screening unit; at least one vibratory drive motor installed on said longitudinal counterbalance member; and a plurality of isolation springs supporting said longitudinal counterbalance member.   
     
     
         5 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly includes a variable speed motor controller for adjusting vibration intensity. 
     
     
         6 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly has a set operating frequency; and said vibration drive isolation assembly having a linear stroke for developing a unidirectional conveying action for directionally vibrating biomass particles to multiple discharge openings located at a defined discharge end. 
     
     
         7 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly has a defined stroke angle and includes drive springs that are in alignment with said stroke angle. 
     
     
         8 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly is positioned under said vibrating screening unit. 
     
     
         9 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly includes a plurality of drive springs being distributed across at least the width of said grate unit. 
     
     
         10 . The vibrating screening feeder of  claim 4 , wherein n said vibration drive isolation assembly includes a longitudinal counterbalance member. 
     
     
         11 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly includes a plurality of isolation springs supporting said longitudinal counterbalance member. 
     
     
         12 . The vibrating screening feeder of  claim 4 , wherein said isolations springs and said drive springs are steel coil springs; said drive springs being stiffer than said isolation springs. 
     
     
         13 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly includes a pair of three phase, A-C squirrel cage vibratory motors installed on said longitudinal counterbalance member. 
     
     
         14 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly includes at least one electrical vibratory drive motor. 
     
     
         15 . The vibrating screening feeder of  claim 4 , wherein said vibration drive isolation assembly includes a variable speed motor controller for adjusting vibration intensity. 
     
     
         16 . The vibrating screening feeder of  claim 4 , wherein said variable speed motor controller being operatively arranged for dynamically adjusting vibration intensity during a timed cycle. 
     
     
         17 . The vibrating screening feeder of  claim 16 , wherein said timed cycle includes an electrical control enabling a full zero to maximum output adjustment by means of adding a standard variable frequency (VFD) combined with adjustable timers so that a vibratory stroke required screening has an automatic capability of a momentary “pulsing” to 60 hertz (or higher) for a brief time of usually 3 to 5 seconds, which generates a “spurt” or “pulse” to the entire screening body for clearing screen media of a lump or a particle stuck in a screen opening or to break free accumulated layers of adhesive and cohesive particles that try to “stick” or adhere to the surface of a screening media and a passed “unders” collecting pan therebelow. 
     
     
         18 . The vibrating screening feeder of  claim 16 , wherein an electrical control enables a full zero to maximum output adjustment by means of adding a standard variable frequency (VFD) combined with adjustable timers so that a vibratory stroke of about 50 Hz for about 25 seconds has an automatic capability of a momentary “pulsing” to 60 hertz or higher for a brief time of from 3 to 5 seconds generating a greater vibratory action to the entire screening body for clearing screen media of a lump or a particle stuck in a screen opening or to break free accumulated layers of adhesive and cohesive particles that try to “stick” or adhere to the surface of a screening media and a passed “unders” collecting pan therebelow. 
     
     
         19 . The vibrating screening feeder of  claim 4 , wherein said variable speed motor controller includes a variable voltage motor controller. 
     
     
         20 . The vibrating screening feeder of  claim 4 , wherein said variable speed motor controller includes a variable frequency motor controller. 
     
     
         21 . A method of vibrating a conveying apparatus to convey material, said method 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 drive spring having a first end attached to said bed and a second end attached to a support, each said drive spring adapted to compress and extend along a line of stroke; providing a plurality of stabilizers attached to said bed, each said stabilizer being more rigid in a direction transverse to said line of stroke than said stabilizer is rigid in the direction of said line of stroke; providing a first vibratory motor having a first rotatable eccentric weight adapted to state about a first axis, a second vibratory motor having a second rotatable eccentric weight adapted to rotate about a second axis, a third vibratory motor having a third rotatable eccentric weight adapted to rotate about a third axis, and a fourth vibratory motor having a fourth eccentric weight adapted to rotate about a fourth axis, said first and second axis being located substantially in a first plane and said third and fourth axes being located substantially in a second plane, said second plane being non-coplanar with said first plane said first and second axes being spaced from said third and fourth axes along the direction the material is conveyed, said eccentric weights being free-wheeling with respect to one another, each said vibratory motor adapted to operate at substantially the same operating speed and to provide an output force generally perpendicular to its axis of rotation, said rotatable eccentric weights adapted to accumulatively synchronize with one another without being rotationally coupled to one another such that the combined resulting output force of said first pair of rotatable eccentric weights is generally parallel to said line of stroke and the combined resulting output force of said second pair of rotatable eccentric weights is generally parallel to said line of stroke; operating said vibratory motors to rotate said eccentric weights, such that said rotating eccentric weights 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 each said vibratory motor at substantially the same selected operating speed which approaches being equal to, or is less than, the natural frequency of said drive springs which are vibrating said bed. 
     
     
         22 . The method of  claim 21  including the step of operating said pair of vibratory motors located closest to said outlet end of said bed so as to provide a greater force output than the remainder of said pairs of vibratory motors. 
     
     
         23 . The method of  claim 21  including the step of uniformly adjusting the vibration frequency of said bed by electrically and simultaneously adjusting the rotational speed of each of said vibratory motors, while said vibratory motors continue to operate at substantially the same rotational speed with respect to one another. 
     
     
         24 . The method of  claim 21  including the step of adjusting the operating stroke and frequency of said drive springs and stabilizers by use of an electrical control connected to each said vibratory motor for simultaneously changing the rotational speed of said vibratory motors, while said vibratory motors continue to operate at substantially the same rotational speed with respect to one another. 
     
     
         25 . The method of  claim 21  wherein said first and second rotatable eccentric weights are rotated in opposite directions relative to one another, and said third and fourth rotatable eccentric weights are rotated in opposite directions relative to one another.