US3666095A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vibrating screen for fine screening of liquids
Assignee: FMC Corp
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Filing: 1970-02-02
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Granted: 1972-05-30
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Expires: 1990-02-02
Abstract
Abstract A vibrating screen is provided for screening with cloths having 60 to 100 mesh openings. A rotary vibrator mechanism producing a minimum stroke of five-sixteenths inch is located above the screen cloth and forward of the longitudinal center of the screen box to obtain a high acceleration and unequal elliptical motion at the ends of the box. The screening surface has a first horizontal section and a second section sloped downwardly at 5* to obtain maximum dewatering on the first section and maximum retention on the second section. Adjustable flow control vanes are included in the feed flume.
Inventors
- 👤 Robert A Krynock
- 👤 Robert W Ruhe Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:05
CPC Classifications
B; B07; B07B; B07B1/00; B07B1/46; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18056; Y10T74/18064
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
424 words
In a vibrating screen of the type including a base, a screen box having a feed end and a discharge end, said screen box resiliently supported on the base, and a drive, said vibrating screen used for the fine screening of solids from a slurry containing solids, the improvements which comprise: a. a feed box attached to said base on the feed end of said screen box, said feed box providing surge storage capacity to even out fluctuations in the volume of slurry fed to the screen, said feed box having a slurry feed inlet opening at the bottom of said feed box near the bottom portion of said base, said feed box having a transition section rising vertically from said inlet opening increasing in width to the full width of said screen box and having a flume section connected to the upper end of the transition section, said flume section having a slurry discharge opening extending across the full transverse width of said screen box, said discharge opening in the flume section located substantially above and projecting over the feed end of said screen box, sufficient to impart potential energy to the slurry to increase its impact on the screen cloth; b. adjustable flow control vanes mounted in the flume section to uniformly distribute the slurry across the full width of said screen box and to direct the flow of the slurry in a direction parallel to the longitudinal axis of said screen box; downwardly c. a screen deck attached to said screen box, said screen deck having spaced apart longitudinal and transverse members connected together to form a single rigid unit, said screen deck comprising a first horizontal section adjacent the feed end of said screen box and a second section downwardly inclined in the direction of flow, said second section starting at a lower elevation than the end of said first section; d. a fine mesh screen cloth resiliently mounted on each section of said screen deck and removably secured to saId screen box; e. a rotating eccentric weight vibrator attached to said screen box above said screen cloth, said vibrator being connected to said drive, said vibrator is located slightly forward of the longitudinal center of said screen box toward the discharge end, and f. coil springs at both the feed end and the discharge end of said screen box resiliently supporting said screen box on said base, whereby elliptical vibrating motion is produced at both the feed end and the discharge end of said screen box by said vibrator.
Claim 2
Dependent Claim
424 words
In a vibrating screen of the type including a base, a screen box having a feed end and a discharge end, said screen box resiliently supported on the base, and a drive, said vibrating screen used for the fine screening of solids from a slurry containing solids, the improvements which comprise: a. a feed box attached to said base on the feed end of said screen box, said feed box providing surge storage capacity to even out fluctuations in the volume of slurry fed to the screen, said feed box having a slurry feed inlet opening at the bottom of said feed box near the bottom portion of said base, said feed box having a transition section rising vertically from said inlet opening increasing in width to the full width of said screen box and having a flume section connected to the upper end of the transition section, said flume section having a slurry discharge opening extending across the full transverse width of said screen box, said discharge opening in the flume section located substantially above and projecting over the feed end of said screen box, sufficient to impart potential energy to the slurry to increase its impact on the screen cloth; b. adjustable flow control vanes mounted in the flume section to uniformly distribute the slurry across the full width of said screen box and to direct the flow of the slurry in a direction parallel to the longitudinal axis of said screen box; downwardly c. a screen deck attached to said screen box, said screen deck having spaced apart longitudinal and transverse members connected together to form a single rigid unit, said screen deck comprising a first horizontal section adjacent the feed end of said screen box and a second section downwardly inclined in the direction of flow, said second section starting at a lower elevation than the end of said first section; d. a fine mesh screen cloth resiliently mounted on each section of said screen deck and removably secured to saId screen box; e. a rotating eccentric weight vibrator attached to said screen box above said screen cloth, said vibrator being connected to said drive, said vibrator is located slightly forward of the longitudinal center of said screen box toward the discharge end, and f. coil springs at both the feed end and the discharge end of said screen box resiliently supporting said screen box on said base, whereby elliptical vibrating motion is produced at both the feed end and the discharge end of said screen box by said vibrator.
Claim 3
Dependent Claim
46 words
A vibrating screen as defined in claim 1 wherein said vibrator is provided with a total stroke of vibration of at least five-sixteenths inch, whereby sufficient motion is provided to toss the slurry and to reduce the blinding of the screen cloth by the fine solids.
Claim 4
Dependent Claim
10 words
a bearing mounted in each end of said tubular housing;
Claim 5
Dependent Claim
10 words
a bearing mounted in each end of said tubular housing;
Claim 6
Dependent Claim
27 words
a rotating shaft concentrically mounted in said bearings and having a single extension on one end beyond the bearings, nd a double extension on the otheR end;
Claim 7
Dependent Claim
27 words
a rotating shaft concentrically mounted in said bearings and having a single extension on one end beyond the bearings, nd a double extension on the otheR end;
Claim 8
Dependent Claim
34 words
A vibrating screen as defined in claim 2, wherein said vibrator is operated at a rotational speed of at least 1,100 RPM, whereby a relatively high rate of acceleration is provided to the slurry.
Claim 9
Dependent Claim
18 words
A vibrating screen as defined in claim 3, wherein said vibrator is a spring controlled, speed responsive vibrator.
Claim 10
Dependent Claim
42 words
a hub attached to the shaft extension on each end of said shaft adjacent the bearings having a spring seat on one projection of the hub over said shaft and a depending clevis type flange on the opposite side of the hub;
Claim 11
Dependent Claim
42 words
a hub attached to the shaft extension on each end of said shaft adjacent the bearings having a spring seat on one projection of the hub over said shaft and a depending clevis type flange on the opposite side of the hub;
Claim 12
Dependent Claim
19 words
a pair of counterweights, each pivotally mounted on the clevis flange of each hub equidistant from the shaft centerline;
Claim 13
Dependent Claim
19 words
a pair of counterweights, each pivotally mounted on the clevis flange of each hub equidistant from the shaft centerline;
Claim 14
Dependent Claim
24 words
A vibrating screen as defined in claim 4, wherein said screen cloth has at least 60 openings per lineal inch of the screen cloth.
Claim 15
Dependent Claim
18 words
a spring mounted on each of the spring seats extending away from said hub opposite to said counterweights;
Claim 16
Dependent Claim
18 words
a spring mounted on each of the spring seats extending away from said hub opposite to said counterweights;
Claim 17
Dependent Claim
398 words
In a vibrating screen of the type including a base, a screen box having a feed end and a discharge end resiliently supported on the base and a drive, said vibrating screen used for the fine screening of solids from a slurry containing solids, the improvements which comprise: a. a feed box attached to said base on the feed end of said screen box, said feed box rising vertically from a central slurry feed inlet opening near the bottom of the feed box on the transverse centerline of the screen, said feed box uniformly increasing in width through a transition section to a rectangular flume section of the full transverse width of the screen, said flume section having a discharge opening extending substantially above and projecting over the feed end of said screen box, sufficient to impart potential energy to the slurry to increase its impact on the screen cloth; b. flow control means mounted transversely across the flume section to uniformly distribute the feed slurry across the full width of the screen and to direct the flow in the direction of the longitudinal axis of said screen box; c. a screen deck attached to said screen box, having spaced apart longitudinal and transverse members welded together to form a single rigid unit, said screen deck having a first horizontal section followed by a second section downwardly inclined slightly in the direction of flow, said horizontal first section providing a longer retention time than a correspondingly sized inclined section and said inclined second section providing gravitational assistance to convey the oversize solids off the end of said second section; d. a fine mesh screen cloth resiliently mounted on each section of said screen deck and removably secured to said screen box; and e. speed responsive vibrator means attached to said screen box and connected to said drive, said vibrator means being located forward of the longitudinal center of said screen box toward the discharge end, whereby elliptical vibrating motion is produced at the ends of the screen to effect slightly more vertical motion at the discharge end than at the feed end, said vibrator means further being provided with a total stroke of vibration of at least five-sixteenths inch and being operated at a rotational speed of at least 1,100 RPM to provide a relatively high rate of acceleration to the slurry being screened, said vibrator means comprising:
Claim 18
Dependent Claim
398 words
In a vibrating screen of the type including a base, a screen box having a feed end and a discharge end resiliently supported on the base and a drive, said vibrating screen used for the fine screening of solids from a slurry containing solids, the improvements which comprise: a. a feed box attached to said base on the feed end of said screen box, said feed box rising vertically from a central slurry feed inlet opening near the bottom of the feed box on the transverse centerline of the screen, said feed box uniformly increasing in width through a transition section to a rectangular flume section of the full transverse width of the screen, said flume section having a discharge opening extending substantially above and projecting over the feed end of said screen box, sufficient to impart potential energy to the slurry to increase its impact on the screen cloth; b. flow control means mounted transversely across the flume section to uniformly distribute the feed slurry across the full width of the screen and to direct the flow in the direction of the longitudinal axis of said screen box; c. a screen deck attached to said screen box, having spaced apart longitudinal and transverse members welded together to form a single rigid unit, said screen deck having a first horizontal section followed by a second section downwardly inclined slightly in the direction of flow, said horizontal first section providing a longer retention time than a correspondingly sized inclined section and said inclined second section providing gravitational assistance to convey the oversize solids off the end of said second section; d. a fine mesh screen cloth resiliently mounted on each section of said screen deck and removably secured to said screen box; and e. speed responsive vibrator means attached to said screen box and connected to said drive, said vibrator means being located forward of the longitudinal center of said screen box toward the discharge end, whereby elliptical vibrating motion is produced at the ends of the screen to effect slightly more vertical motion at the discharge end than at the feed end, said vibrator means further being provided with a total stroke of vibration of at least five-sixteenths inch and being operated at a rotational speed of at least 1,100 RPM to provide a relatively high rate of acceleration to the slurry being screened, said vibrator means comprising:
Claim 19
Dependent Claim
11 words
a cap mounted over the top of each of said springs;
Claim 20
Dependent Claim
11 words
a cap mounted over the top of each of said springs;
Claim 21
Dependent Claim
78 words
A screen as defined in claim 6, wherein said drive further comprises a motor supported directly on said screen box, a counterweight fixed to said screen box on the side opposite said motor to counterbalance said weight of said drive, a second sheave secured to the shaft of said motor, and an endless transmission belt drivingly connecting said motor and said vibrator means, whereby said motor moves with said screen box eliminating excessive belt whipping and early failure.
Claim 22
Dependent Claim
79 words
linkage means pivotally connecting said cap and said counterweights at a point beyond the pivot mounting of said counterweights to said hubs, whereby the spring restrains the counterweights in a dynamically balanced condition about the shaft centerline until the centrifugal force due to the speed of rotation in the rotating counterweights is sufficient to overcome the springs'' restraining force and permits the counterweights to pivot radially outward to become dynamically unbalanced so as to produce a vibrating motion; and
Claim 23
Dependent Claim
79 words
linkage means pivotally connecting said cap and said counterweights at a point beyond the pivot mounting of said counterweights to said hubs, whereby the spring restrains the counterweights in a dynamically balanced condition about the shaft centerline until the centrifugal force due to the speed of rotation in the rotating counterweights is sufficient to overcome the springs'' restraining force and permits the counterweights to pivot radially outward to become dynamically unbalanced so as to produce a vibrating motion; and
Claim 24
Dependent Claim
40 words
A screen as defined in claim 6, wherein a tank extending substantially under the area of the screen box is integrally formed into said base with a discharge outlet on each longitudinal side for the collection of the undersize material.
Claim 25
Dependent Claim
87 words
A screen as defined in claim 6, wherein said screen deck has a difference in elevation between the first section and the second section and has a connecting flow plate at an intermediate elevation, whereby the solid particles flowing over the end of the first section reorient their direction as they drop and impact on the connecting flow plate and the beginning of the second section which tends to break up any large globules to make further size and moisture separation more efficient on the second section.
Claim 26
Dependent Claim
18 words
a drive sheave secured to the outer end of said double shaft extension for connecting to said drive.
Claim 27
Dependent Claim
18 words
a drive sheave secured to the outer end of said double shaft extension for connecting to said drive.
Claim 28
Dependent Claim
53 words
A screen as defined in claim 9, wherein said screen deck has a transverse convexly shaped camber not exceeding one quarter of an inch per foot of screen width, whereby said screen cloth can be stretched over the screen deck to eliminate unevenness without causing the material to be screened to flow laterally.
Claim 29
Dependent Claim
50 words
A screen as defined in claim 10, wherein said screen deck has longitudinal support bars having a transverse spacing not exceeding 6 1/2 inches, said support bars further having soft cushioning strips on their top edges for supporting said screen cloth to extend its fatigue life under the vibrating action.
Claim 30
Dependent Claim
18 words
A screen as defined in claim 11, wherein the screen cloth has openings no larger than 60 mesh.
Claim 31
Dependent Claim
376 words
In a vibrating screen of the type including a base, a screen box having a feed end and a discharge end, said screen box resiliently supported in the base, and a drive, said vibrating screen used for the fine screening of solids from a slurry containing solids, the improvements which comprise: a. a feed box attached to said base on the feed end of said screen box, said feed box having a slurry feed inlet opening at the bottom of said feed box near the bottom portion of said base and on the transverse centerline of the screen, said feed box further having a transition section rising vertically from said inlet opening and having a rectangular flume section connected to the upper end of the transition section, said flume section having a slurry discharge opening extending across the full transverse width of said screen box, said discharge opening In the flume section located substantially above and projecting over the feed end of said screen box, sufficient to impart potential energy to the slurry to increase its impact on the screen cloth; b. a screen deck rigidly mounted within said screen box having spaced apart longitudinal and transverse members connected together to form a rigid unit and having a transverse convexly shaped camber to the top surface of said screen deck not exceeding one quarter of an inch rise per foot of screen box width; c. a screen cloth having openings no larger than 250 microns resiliently supported on said screen deck and removably secured to said screen box; and d. a rotating eccentric weight vibrator means attached to said screen box above said screen deck and located slightly forward of the longitudinal centerline of said screen deck toward the discharge end; and e. coil springs at both the feed end and the discharge end of said screen box resiliently supporting said screen box on said base, whereby elliptical vibrating motion is produced at both ends of said screen box, the vibrating motion at the discharge end having slightly more vertical motion than at the feed end, the horizontal motion at the feed end being directed in the direction of flow, and the horizontal motion at the discharge end being opposed to the flow of the slurry.
Claim 32
Dependent Claim
376 words
In a vibrating screen of the type including a base, a screen box having a feed end and a discharge end, said screen box resiliently supported in the base, and a drive, said vibrating screen used for the fine screening of solids from a slurry containing solids, the improvements which comprise: a. a feed box attached to said base on the feed end of said screen box, said feed box having a slurry feed inlet opening at the bottom of said feed box near the bottom portion of said base and on the transverse centerline of the screen, said feed box further having a transition section rising vertically from said inlet opening and having a rectangular flume section connected to the upper end of the transition section, said flume section having a slurry discharge opening extending across the full transverse width of said screen box, said discharge opening In the flume section located substantially above and projecting over the feed end of said screen box, sufficient to impart potential energy to the slurry to increase its impact on the screen cloth; b. a screen deck rigidly mounted within said screen box having spaced apart longitudinal and transverse members connected together to form a rigid unit and having a transverse convexly shaped camber to the top surface of said screen deck not exceeding one quarter of an inch rise per foot of screen box width; c. a screen cloth having openings no larger than 250 microns resiliently supported on said screen deck and removably secured to said screen box; and d. a rotating eccentric weight vibrator means attached to said screen box above said screen deck and located slightly forward of the longitudinal centerline of said screen deck toward the discharge end; and e. coil springs at both the feed end and the discharge end of said screen box resiliently supporting said screen box on said base, whereby elliptical vibrating motion is produced at both ends of said screen box, the vibrating motion at the discharge end having slightly more vertical motion than at the feed end, the horizontal motion at the feed end being directed in the direction of flow, and the horizontal motion at the discharge end being opposed to the flow of the slurry.
Claim 33
Dependent Claim
24 words
A screen as defined in claim 13, wherein said vibrator means is provided with a total stroke of vibration of at least five-sixteenths inch.
Claim 34
Dependent Claim
22 words
A screen as defined in claim 14, wherein the vibrator means is operated at a rotational speed of at least 1100 RPM.
Claim 35
Dependent Claim
47 words
A screen as defined in claim 15, whereby the screen deck has a first horizontal section at the feed end followed by a second section downwardly inclined about 5* in the direction of flow having a difference in elevation between the two sections of about three inches.
Claim 36
Dependent Claim
39 words
A screen as defined in claim 16, wherein the vibrator means is a rotating, spring controlled speed responsive vibrator, whereby the vibrator remains dynamically balanced during starting and stopping but becomes dynamically unbalanced as it approaches normal operating speed.
Claim 37
Dependent Claim
52 words
A screen as defined in claim 17, wherein a plurality of adjustable, vertically pivotable vanes are mounted transversely across the flume section of said feed box to uniformly distribute the feed liquid across the full width and to direct the flow in the direction of the longitudinal axis of said screen box.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |