US2915183A - Vibrating screen - Google Patents

Description

Dec. l, 1959 w. E. sAxE 2,915,183

VIBRATING SCREEN Filed July 6, 1954 4 sheets-sheet 1 WALTER E'. SAXE,

INVENTOR.

HUEBNER, aEEf/L En, won/m. a Hmz/c,

By! D DATTRNEVSZ l, 1959 w. E. sAxE VIBRATING SCREEN 4 Sheets-Sheet 2 Filed July 6. 1954 vlm i AT WW.

WALTER E. SAXE, INVENTOR.

HUEBNER, BEEHL El?,

WOR/PEL HERZ/G,

Dec. l, 1959 w. E. sAXE 2,915,183

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IN VEN TOR.

HuEs/vEmaEEf/L En, Wonne/ a HERZ/c, By U ATTORNEKSZ Dec. 1, 1959 w. E. sAxE 42,915,183

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' AHORA/Em Mika United States Patent O The invention relates to power operated screens and has particular reference torelatively large screens for commercial use which are vibrated in order to advance the aggregate over the screen and wherein the vibrating mechanism is adapted to adjustment in order to acconimodate diierent types of aggregate and diierent conditions.

The application is a continuation-impart of co-pend ing application Serial No. 296,374, led June 30, l952,

now Patent No. 2,707,559, issued May 3, 1955.

Although attempts have been mare heretofore to provide screening devices which are power operated, where attempts have been made to shakethe screen by use of power, the mechanism has been extremely inadequate to meet varying c onditions for screens of diferent types. Movement of a iixed type has apparently been considered sutlicient and little or no attention has been given to providing a means of adjusting the movement or shaking effect to produce a versatile machine with relatively little application of force. Further still, where agitation has been resorted to, attempts to advance the larger particles screened out by the process to a location where in a continuous process they can be discharged from the screen have not been satisfactory.

It is therefore an object of 'this invention to provide controlled vibration at approximately right angles to the screening medium in preference to what may be termed circular vibration, which circular vibration wastes a large portion of the operation in motion which only disturbs the screening action by striking the material particles sideways instead of moving directly at them to produce a more orderly and controlled advance of the material over the screen. i i, .i

lt is further among the objects of the invention to provide a new and improved power operated screen so constructed that it can handle relatively heavy loads at a continuous rate and further so constructed that the material being screened is steadily and gradually advanced toward a discharge end of the screen in order that the screening surface may be kept clear of larger particles which are screened out.

Another object of the invention is to provide a vibrating screen wherein the application of vibrating force is in a plane tilted with respect to horizontal so that particles screened out are advanced from a loading end of the screen to a discharge end of the screen either by reason of the tilt o f the screen, by reason of the application oi the vibrating force, or a combination of both. e

Still another object of the invention is to provide a new and improved power vibrated screen device wherein l`the application .of vibrating power to a screening surface is in such variety that e number of individual screens cell be mounted in vseries so that aggregate to be screened after beine passeduover one screen ceu be discharged upon-successive. screens ,in e continuous Process With'vibretions adjusted to the `screen size thereby to divide ou,t Particles ot .a stent ,runny .ditlerent sizes by use of screens of diierent mesh one in series with the next.

2,915,183 VEatented Dec. l, 1959 ICC Still another object of the invention is, to provide a` vibrating elementfor articles in the nature of vibrating screens so constructed that weight in the olf-,center port tion of the vibrating elementcan be changedwhile the, opertaion is in progress so as to change the vibrating characteristics of the off-center mechanism without it being necessary to make mechanical or physical adjustments in those portions of the device. e

Still further among the objects of the invention is to provide for vibrating different portions of thel screen atl different rates as, for example, by changing the speed of rotation o f ythe vibrator as well as adjusting the vi-V bretor physically, thereby to produce different vibrational characteristics in the saine screen et ,dilerent stages ol the screening process,

Further still anions the objects of vthe invention is to provide a movable mounting means for securing a vibrat-l ing screen to a stationary support which will readily p er` mit application ot .e variety of, vibrational characteristics to the 'screen While .at the seine time -firmly holding the ,screen in its location upon the support With these and other objects. in view, the invention consists in the construction, arrangement and combina; tion of the various, parts of the device whereby the .objects contemplated are attained, as hereinafter slet forth, pointed out in the appended claims .and illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a plan view of one form of the device ilmlostrating the invention.

Figure 2 is a side elevational view of the screen shown in Figure 1.

Figure 3 is a partial cross-sectional view taken on the line 3-3 of Figure 2.

Figure 4 is a crossfsectional view through one of the vibrating elements partially broken away teken on. the line 4-4 of Figure 2. v v a Figure 5 is a fragmentary longitudinal sectionalview on the line 5-5 of Figure 4 l Figure 6 is a planview of a multiple drive arrange,- ment showing a screen o f extra length in ycombination With e multiple vibrator rnechenistnv Figure 7 4is aside elevational view :of the screen of. Figure 6.

Figure 8 is a plan view of still another forrn'of the device. a e

Figure 9 .is a side elevational view .of the device .shown in Figure r8. i

Figure 10 is a plan view partially kbroken away showing still another form of the device.

Figure ll is aside elevational view ofthe device shown in Figure 10.

Figure 12 is av plan view of still another form ofthe invention showing weights located onall sides of the screen.

Figure 1,3 is a side` elevational view on the line 13-13 of Figure l2.

In the form of the device illustrated in Figures 1 to 4, inclusive, there is shown a pair etk supportingchannels 10 and 11 resting upon S9111@ permanent stationary surface 12 to which they may besecured by appropriate conf ventional means,.not shown. A screen frame indicated generally by the'reference character 13 is mounted upon the supporting channels in a horizontal plane. The screen frame -consists of frame channels 14 and 15 forming the llongitudinal sides of the screen frame. "l`hese'chan-` nels are secured together byl cross beams 16 and ,117,

suitably welded in place. The rectangular screen frame i upturned rigid flange 21 on the screen is engaged by the hooked member 19. On the opposite side of the screen a similar upturned'flange 22 is adjustably secured by means of a screw hook 23 held in the upstanding leg of an angle bar 24, this bar in turn being fastened to the channel 15. By this means the screen may be firmly stretched over the top of the screen frame.

In order to resiliently support the screen frame upon the supporting channels and 11, there are provided a series of rods or columns 2S on each side. Each rod has an eyelet 26 at the top'adapted to receive a bolt 27, thereby to pivotally secure the eyelet to a boss 28 in turn fastened to the channel 14 or 15, as the case may be. Similar means is used to secure the bottom end of each rod 25 to the appropriate supporting channel as, for example, an eyelet 29' secured by a bolt 29. The rods and their securing bolts are in a parallelogram arrangement, as clearly shown in Figure 2, so that thevscreen frame is free to raise and lower, dependingl upon its resilient support, and as it raises or lowers it maintains itself in a horizontal plane.

To secure the screen frame in elevated position, there is provided an upstanding bracket 30 secured to the supporting channel 11 by means of a bolt 31. A downwardly extending bracket 32 is secured at the upper end of the bracket to the lower flange of the frame channel 14 or 15, as the case may be, by welding or other appropriate means. As noted there is a pair of the brackets 30, 32 on each side of the frame. The brackets have free ends locatedopposite each otherin spaced relation, as indicated particularly in Figure 2. A bolt 34 extends through the lower end of the bracket 32 and thence over the distance between the bracket and throughthe upper end of the bracket 30. A spring is interposed between the bracket 30 and a nut 36 and surrounds the bolt. By providing a device as just described on each side of the frame, the frame -is held in elevated position from which position it can be vibrated upwardly against the compression of the spring 35 as the operation proceeds.

To provide motive power properly located to vibrate the screen a pedestal 37 is mounted upon the stationary surface 12 at the upper end of which is a platform 38 supporting a motor 39. From the motor a belt drive 40 is connected to a pulley 41 keyed upon a shaft 42.

yThe shaft in turn is rotatably mounted upon bearing brackets 43, 44, 45 and 46 secured to the cross beam 17 of the frame.

At each end of the shaft 42 is a bevel gear 47 meshing with a similar bevel gear 48 on a shaft 49. The shaft 49 in turn is mounted upon bracket 50 which is secured to the respective frame channel and 51 secured to the lower end of the bracket 32. The shaft 49 is mounted in an oblique direction substantially parallel to the direction of the rods 25 and slightly oblique relative to the axis of the bolt 34.

` Non-rotatably mountedV on the shaft 49 is a hollow cylindrical housing 52 shown in detail in Figures 4 and 5.

The cylindrical housing is mounted off-center upon the shaft. Inside of the housing is a pair of eccentric weights 53 and 54 located, as shown in Figure 4, so as to provide a space or chamber 55 therebetween. rl`he shaft 49 is a tubular shaft and has a block 56 therein through which passes a pipe 57 centrally disposed within the shaft 49. The pipe protrudes through the block and has a right angularly bent portion 58 extending radially outwardly of the housing S2 and centerably disposed within the charnber 55. The portion 58 of the pipe terminates near an inner wall 59 of the housing 52. Although the eccentric weights 53, 54 provide for the vibration of the shaft and consequently the screen, the vibration characteristic can be altered by varying the quantity of a liquid 60 in the chamber 55, the chamber being closed as indicated by a plate 61. The pipe 57 may be connected by suitable means, not shown, to a source of the liquid 60 and additional liquid passed into the chamber 55 for the achievement of certain vibrational characteristics where a heavier weight might be needed or withdrawn from the chamber for other vibrational characteristics where a lighter weight might be needed.

When the screen of Figures l, 2 and 3 is set in vibration by operation of the motor 39, the direction of application of the vibrating force is in an angular direction toward the right from vertical as viewed in Figure 2, this because of the direction of mounting of the shaft 49. The force imparted by the vibration is at the left end of the screen, as viewed in Figure 2. When aggregate is loaded at this end of the screen, which may be considered as the loading end, the aggregate will be bounced step by step toward the right, during which time the liner aggregate falls through the screen and the coarser aggregate which cannot pass the screen gradually passes to the right end of the screen where it can be projected oi the screen to be collected by a suitablel receptacle, not shown, beneath the right end of the screen. The vibrational characteristics of the vibrator may be varied to suit different types of aggregate placed on the screen or perhaps different kinds of screenings which it may be desired to collect.

In a second form of the invention illustrated in Figures 6 and 7 there is shown a single long screen 70. The screen is supported at the corners of each by means of a rod 72 extending upwardly to a link 73 which in turn passes through a beam support 74 at the upper end of which is a spring housing 75 having a spring 76 therein. The link 73 is attached to the spring at its upper end so that the spring acts in compression to resiliently support the respective corner of the screen 70. Intermediate supports may also be used. It should be noted that an eyelet 77 is used to connect the rod 72 to the screen, the eyelet connection being similar to the connection between the rod and the link 73 suicient that there be a certain freedom of motion at these points.

The screen in turn comprises frame channels 7S and 79 having beams 81 at the opposite ends, one of which is shown in Figure 6, whereby to complete the frame construction. Screen Wire 82 is stretched over the frameand secured in the same manner as described in connection with Figures l, 2 and 3. It will further be noted that the frame and screen wire thereon occupies a position in a horizontal plane in the case of Figures 6 and 7.

For imparting vibration to the screen at different locations along its length there is provided a shaft 83 rotatably mounted one on each side of one end of the screen by means of bearing brackets 84, 85 and 86. There is an appreciable obliqueness or slope to the mounting of the shaft 83 in each case. Vibration is produced by the presence of eccentric weights 87 and 88 non-rotatably secured to the shaft 83. Effective vibration is achieved when the weights 87 at the upper ends of the shaft 83 have their off-center weighted portions extending in opposite directions when the weighted portions are in the same plane. To this end the weighted portions will both be directed upwardly at the same time and downwardly at the same time, therebyy to act together. In side positions such as that shown in Figure 6, they counter-balance each other so that there is no sideward thrust or vibration imparted to the screen.

To provide for rotation of the'shaft 83, power is taken from a suitable source and transferred through a belt drive 89 to a pulley 90 non-rotatably mounted upon a shaft 91. The shaft in turn is rotatably mounted by means of brackets 92, 93, 94 and 95 to the frame and in particular to the cross-beam 81. A bevel gear 96 is located at each end of the shaft 91, meshing with a similar bevel gear 97 at the upper end of the shaft 83. By this train of power, shafts 83 on opposite sides of the frame are rotated at the same rate of speed and simultaneously with respect to the weights 87. The tilted direction of the shaft 83 effects an application of vibrational force an `oblique direction toward the right, as

viewed in Figures 6 and 7. This tiltedor oblique application of vibrating force tends to advance thev heavier particles which do not pass through themesh of the screen in periodic jumps from the left end of the screen toward the right end of the screen as the liner particles are sifted or screened through. Hence the left end of the machine may be designated as the loadingend.

To secure a continuous operation and in order to screen out all particles of the various different size which comprise the aggregate, minimizing waste dumped oithe discharge end, the screen may be made virtually any desired length, as illustrated.

To continue the application of power from the vibrating portion of the left end of the screen to the right end of the screen, a sprocket 98 is mounted atthe lower end of the shaft 83 and has a chain 99 extending thereover toy a sprocket 100 at the upper end of the shaft 83 of the screen 71. When the sprockets 98 and 100 are made of the same diameter and number of teeth, rotation of the shafts 83 on the left and right ends of the screen, respectively, will be at the same rate of speed. Obviously, ifvthe screen be extra long, it is further possible to add still a third vibrating mechanism, not shown, in exactly the same fashion as already described. The process may thus be extended to any reasonably desirable length without varying structure from that shown and described. So long as the application of the vibrational effect is in an oblique direction, particles not screened through the mesh of the screen will continue to advance toward the right until discharged olf the discharge end of the screen.

In still a third form of the device illustrated in Figures 8 and 9 there is provided a tilted support105 comprising channels 106, the upper end of each of which is mounted upon a column 107 and the lower end of eachrof which is mounted upon a pivot ange 108. The column and the pivot ange in turn are bolted to a suitable stationary surface 109. For convenience in adjusting the slope of the support the column 107 may be provided with a series of holes 110 through which a bolt 111 may be passed in order to secure the upper end of the channel 106 on each side in any one of the different positions indicated by the holes.

A screen 112 of the form of the invention of Figures 8 and 9 is constructed in a fashion similar to the screens heretofore described in that they comprise a frame of side channels 113 secured together by transverse beams 11,4, one at each end. A wire mesh 115 is stretched across the upper edges o f4 the frame to provide the screening element.

In the case of Figures 8 and 9 compression springs 116 mounted in pairs support each corner of the frame of the screen, the springs being held by suitable keepers. To more securely anchor the frame upon the supporting channels, there is provided on each side a tension rod 117 pivotally secured at the left end by means of an eyelet 118 in turn attached to a bracket 119 at the upper or left-hand end of the channel 106 by use of a bolt 120. At the right-hand end of the tension rod 117 an eyelet 121 is secured to a bracket 122 by means of a bolt 123. The tension rod thus mounted tends to hold the screen in the position shown in Figure 9 to the extent that as the screen is vibrated transversely relative to the plane of its mounting, it will not tend to be urged toward the right. Freedom of motion up and down permitted by the springs 116 is not impaired.

To vibrate the screen there is provided a motor support 124 upon which is mounted a motor 125 operating a belt drive 126 to rotate a pulley 1217 in turn keyed to a shaft 128 rotatably mounted upon brackets 1219, 130, 131 and 132 on the cross-beam 114. Bevel gears 133 and 134 transfer the rotational eect to shafts 135, one on each side of the frame. The shafts are secured by appropriate brackets 136 to the channel 113 of the frame, the shafts in turn being in a plane parallel to the plane of the mesh 115 and parallel to each other. Eccentric weights 137 are non-rotatably secured to the shaft `on each side and these eccentric weightsimparta vibrational eifectfup and down to the screen when the shafts 135 are rotated, rotation being as show at the same rate of speed. 1

Because of 'the sloping disposition of the screen frame and screen,` the elect of the vibration imparted to the screen is to lift the particlesof aggregate placed at the upper end of the screen upwardly in a direction normal to the surface of the screen. After the apex of the lift curve has been reached, the particles will fall straight down by action of gravity, to a position lower down `on the screen and thus step by step traverse the length of the screen until the particles not screenedxthrough the mesh willV fall from the lower or discharge end of the screen. Therefore, although the shafts'carrying the eccentric weights are mounted parallel to the plane of the screen, nevertheless the effect of vibration imparted to the screen by the eccentric weights on the shaft tends to advance the aggregate from a loading end toward adis? charge end, while the finer screened* aggregate passes through the screen.

vIn still another formv of. the invention illustratedV in Figures 1 0 and 11 there is shown a screen 140 mounted horizontally. The screen is'constructed of two channels 141 suspended at each end by a suspension rod 142 ex.- tending into a spring housing 143 on a stationary support 144 in a manner similarr to themounting described in detail in connection with Figure 7. The mounting referred to provides a resilient support at each of the four corners of the screen. Transverse beams 145 complete the frame structure.

iIn this form of the device there is a shaft 146' rotatably secured to the frame at the left end by means .of brackets y147'. A similar shaft 148 is securedv to the-right end by means of brackets 149. The brackets in each case are suitably bolted to the lowermost flange ofthe channel 141 on each respective side of the frame. Shafts 146 and.148 areparallel to each other and parallel to the horizontal plane in which the screen 140 is mounted. Wire mesh 150 is attached over the frame in the same manner as previously described in connection with the rst and suc ceeding forms of the invention. On each of the shafts 146 and 148 is an eccentric weight 151 shown centerably disposed in the form of the invention selected for the i purpose of illustration.

To elfect rotation of the shafts 146 and 148 there is provided a motor 152 secured to a stationary surface 153 by suitable bolts. The motor is equipped with sprockets 154 and 154' non-rotatably mounted upon a, motor shaft 155. A chain 156 transfers rotational motion from the sprocket 154 to a sprocket 157 non-rotatably mounted upon the adjacent endof the shaft 146. A similar chain 158 transfers rotational motionfrom the sprocket 154 to a sprocket 159 mounted upon an idler shaft 160. Also mounted upon the idler shaft is a gear 161 meshing with `a gear 16,2 of the same diameter. The idler shaftr in turn is mounted for rotation on a suitable idler bracket 163 on the underside of the respective channely 141 at the right end of each. The weights 151 maybe made different if it be desired to vibrate one end of the screen differently from the other. l

lIn the form of `the device illustrated in Figures l2 and 13 vibration is applied at each of four sides of a rectangu lar ,screen assembly 170. The screen assembly is suspended at each of four corners by -a rod 171 mounted on a beam 172 through an appropriate resilient support 173. In this form a motor 174 mounted with its drive sprocket, 175 parallel to the vplane of the screen rotates a master driven shaft 176 by means of a chain 177 and sprocket 178. Bearing brackets 179 support the shaft on the screen assembly. Side shafts 180 and 181 are secured to the screen assembly by brackets 182. In each instance a bevel gear 183 carried by the respective shaft is driven by a corresponding bevel gear 184 on the master driven shaft 176. A shaft 185 secured to the 7 screen assembly by brackets 186 is driven by bevel gears 187 and 188 from thefshaft 181. Each of the shafts has an eccentric weight 189 fixed thereon with the weighted side so located that the weights oppose and balance each other in all directions except the vertical direction, regardless of where along the respective shafts the weights may be set. Hence there will be effective vibrationin a direction perpendicular to the plane of the screen and vibration in this direction will be facilitated by the resilient mountings in the supports 173.

There has accordingly been described herein certain vibrational characteristics and screens having certain inherent vibrational designs such that whether mounted horizontally or tilted the vibration provides for a progress of unscreened aggregate from the loading end to the discharge end, which progress is continuous until the unscreened aggregate is discharged. The screens are so devsigned with respect to their vibrational portions that the vibrating effects may be varied to a certain extent. Moreover, by reason of the design and location of the vibrational portions of the devices, the screens in many cases may be placed end to end so that should a screen of the usual length not be su'lcient to perform the necessary operation, it may be extended to a sufficient length on the same frame without the necessity of providing transfer points and thus effect an efficient continuous operation.

While I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A vibrating screen device comprising a support, a horizontal frame having a screen thereon, a plurality of obliquely extending parallel rods on each side of the screen pivotally connected at ends thereof to the frame and the support, a resilient supporting connection on each side of the screen extending transversely to the axial direction of said columns, a shaft rotatably mounted on each side of the frame at an angle substantially parallel to the axes of said rods, a weight on each shaft'extending off-center in a direction opposite fromvthe weight on the shaft opposite thereto when reaching laterally extended positions, a rotating source of power on the support and a flexible power train from said source to said shaft adapted to rotate said shaft simultaneously at the same speed. Y

2. A vibrating screen device comprising a support, a horizontal frame having a screen thereon, a plurality of obliquely extending parallel columns on each side pivotally connected at ends thereof to the frame and the support, a pair of brackets on each side of the frame, one bracket of each pair comprising an upwardly extending bracket on the support and the other bracket of each pair comprising a bracket on the frame extending downwardly and laterally spaced from said first bracket, a resilient connection between each pair of brackets and extending transversely to the axial direction of said columns whereby to yieldingly fix the location of said frame, a pair of spaced obliquely extending bearings on each side of the frame having axes thereof substantially parallel to the column, and a shaft rotatably mounted in each pair of bearings at an angle substantially parallel to the axes of said columns, a weight on each shaft extending olf-center in ardirection opposite from the weight on the shaft opposite thereto when reacing maximum outer and inner rotative positions, a rotating` source of power on the support and a-flexible power train from said source to said shafty adapted to rotate said shaft simultaneously at the same speed whereby to concentrate the vibration impulses in the screen and isolated from the support.

3. A vibrating device comprising a tubular shaft, and an eccentric device non-rotatably secured to the shaft, said eccentric device comprising a closed hollow housing mounted eccentrically on the shaft and forming a chamber, and a pipe centrally mounted in the tubular shaft and having an open end extending radially outwardly from the shaft and in said chamber to the outer portion thereof and comprising means for changing the quantity of liquid in said chamber whereby to vary the vibration characteristics of the device.

4. A vibrating screen device comprising a tubular shaft rotatably mounted on the screen device, and an eccentric device non-rotatably secured to the shaft, said eccentric device comprising a closed hollow housing mounted eccentrically on the shaft and forming a liquid receiving chamber on one side only of said rod, a liquid partially filling said chamber, and a pipe mounted in the tubular shaft on onefside only of said shaft and having an open end extending radially outwardly in said chamber to the outer portion thereof and comprising means for adding to andsubtracting from the quantity of liquid in said chamber whereby to vary the vibration characteristics of the screen device.

5. A vibrating screen device comprising a support, a screen frame having a plurality of separate resilient connections between opposite sides of the frame and the support, tubular shafts rotatably mounted on opposite sides of the frame in an oblique position relative to a horizontal plane, and an eccentric device non-rotatably secured to each shaft, said eccentric device comprising a closed hollow cylindrical housing mounted eccentrically on the shaft and forming a chamber, eccentric weight elements partially lling opposite sides of the chamber` and forming a space therebetween on one side only of the shaft, a liquid partially filling said chamber a pipe centrally mounted in the tubular shaft and having an open end extending radially outwardly in said chamber to the outer portion thereof and comprising means for adding to and subtracting from the total quantity of liquid in said chamber whereby to vary the vibration characteristics of the screen device.

References Cited in the file of this patent UNITED STATES PATENTS 1,185,611 Dougan May 30, 1916 1,363,495 Cottrell Dec. 28, 1920 2,200,724 Robins May 14, 1940 2,304,573 Kessler Dec. 8, 1942 2,353,492 OConnor July 11, 1944 2,367,070 Symons Ian. 9, 1945 2,596,281 OBrien May 13, 1952 2,597,503 Larsson May 20, 1952 2,634,617 Dryg Apr. 14, 1953 2,707,559 Saxe May 3, 1955 2,722,840 Kececioglu Nov. 8, 1955 FOREIGN PATENTS 854,007 Germany Oct. 30, 1952 722,218 Great Britain Jan. 19, 1955

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