US3076549A

US3076549A - Vibrating unit for screening and feeding

Info

Publication number: US3076549A
Application number: US11852A
Authority: US
Inventors: George D Becker
Original assignee: Nordberg Manufacturing Co
Current assignee: Nordberg Manufacturing Co
Priority date: 1960-02-29
Filing date: 1960-02-29
Publication date: 1963-02-05
Anticipated expiration: 1980-02-05

Description

Feb. 5,; 1963 G. Di BECKER VIBRATING UNIT FOR SCREENING AND FEEDING Filed Feb. 29, 1960 4 Sheets-Sheet 1 as m INVENTOR. & "5 g eorqe DMBeCIe/Z N parker Z, Carzer Ht tormgg s- Feb. 5,; 1963 G. D. BECKER VIBRATING UNIT FOR SCREENING AND FEEDING Filed Feb. 29. 1960 4 Sheets-Sheet 2 IN VEN TOR.

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VIBRATING UNIT FOR SCREENING AND FEEDING Filed Feb. 29, 1960 4 Sheets-Sheet 3 IN VEN TOR.

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VIBRATING UNIT FOR SCREENING AND FEEDING Filed Feb. 29, 1960 4 Sheets-Sheet 4 :F I I I i l l I I l I g l E L? T :1: F m 1 x v LA A l H NM F a INVENTOR. g Q g earqe Becker,

United States Patent Ofiiice 3,076,549 Patented Feb. 5, 1963 3,076,549 VIBRATING UNIT FOR SCREENING AND FEEDING George D. Becker, Wauwatosa, Wis., assignor to Nordberg Manufacturing Company, Milwaukee, Wis., a corporation of Wisconsin Filed Feb. 29, 1960, Ser. No. 11,852 2 Claims. (Cl. 209-367) This invention relates to a screen assembly, and in particular to improved means for providing vibratory motion thereto.

One purpose of the present invention is a screen assembly including a simple and eflicient drive means for providing vibratory motion.

Another purpose is an improved wear-resistant, drive arrangement for vibrating a screen assembly.

Another purpose is an improved means for providing straight line vibratory motion for a screening assembly or the like.

Another purpose is an improved drive arrangement for rotating a pair of weights in opposite directions about a common shaft.

Another purpose is an improved drive arrangement for simultaneously driving a plurality of actuators each of which include a pair of weights rotating in opposite directions.

Another purpose is an improved means for vibrating a screen assembly which includes a pair of counter rotating unequal weights which produce elliptical vibration.

Other purposes will appear in the ensuing specification, drawings and claims.

The invention is illustrated diagrammatically inthe following drawings wherein:

FIGURE 1 is a perspective View of a screening assembly with the improved drive means of the invention included thereon,

FIGURE 2 is an enlarged section along plane 2-2 of Figure 1, and

FIGURE 3 is a section along plane 33 of FIGURE 2.

FIGURE 4 is an enlarged view, similar to FIGURE 2, showing a further form of the invention.

n FIGURE 1, a screening assembly 10, which as shown herein is supported as a free body, is suitably supported at the four corners thereof by rods 12 suspended from springs 14. The screening assembly includes side plates 16 having out turned flanges 18 along the top and bottom thereof, and an end plate 20 closing one end of the assembly. It should be noted that the opposite end 22 of the assembly may be open so that if the material to be screened or sifted is introduced at one end, the end adjacent theplate 20, and the vibratory motion of the screen has a horizontal component as well as a vertical component, the material being screened will be gradually directed toward the open end. The assembly shown herein may be used in sizing, sorting, grading or otherwise and is particularly useful in mining operations.

It is conventional in screening assemblies of the type shown herein to provide a driving means which provides or imparts vibratory motion, generally in a straight line, to the screen. This vibratory motion may be provided by a pair of weights adapted to rotate in opposite directions on a shaft projecting outwardly from the side of the screening assembly. The weights are conventionally positioned so that during rotation they will complement and oppose each other every 90 degrees, thus providing points of coincidence 180 degrees apart. A line connecting the points of coincidence forms a straight line which defines the direction of vibration of the actuator. As can be seen in FIGURE 1 there are four actuators providing the driving force for the screening assembly, however there may be more or less depending upon the size and particular application. tion of the actuators may be horizontal, vertical, or at any angular position in between, or my be relatably varied while in use. Additionally, each of the actuators may be set so that the direction of vibration is the same or the actuators may be set with different directions of vibration, so that the material will be moved toward the open end 22 as it is screened.

A suitable driving means, not shown, is connected through a flexible drive member 24, which may be a belt, chain or otherwise, to a driving pulley 26. A drive shaft 30, supported on plate 20 by spaced brackets 28, is rigidly connected to the driving pulley 26 and to two spaced pulleys 31 and 32 which drive the actuators. As shown herein, there is a pair of adjacent actuators along each side of the screening assembly. Each pair of actuators is driven by a drive pulley, either the pulley 31 or the pulley 32. As the actuators and their associated drive means are similar, only one pair of actuators and drive means will be described in detail.

Spaced actuators 34 and 36 are suitably connected to. the screening assembly by means of stub shafts 38 and 40 respectively. The stub shafts are suitably mounted on plates 42, and 44 which are in turn fastened to the. flanges 18.

As each of the actuators is. identical, only. one will be described in. detail. Turning now to FIGURE 3, the actuator is shown to comprise two spaced

wheels

46 and 47 each mounted for independent rotation on stub shaft 48. In the preferred form, each of thewheels include a peripheral outer Wall 49, connected to acenter hub 50 by a web' 50a. A weight 51, which is preferably semicircular, is connected by a bolt 52 to each of the webs. 50a. Suitable bearings 54 positioned between the hubs and stub shaft provide a smooth surface for rotation of the Wheels. nected by screws 55a to the outer the actuator structure.

As clearly shown in FIGURE 3, the outer circum-v ference of each of the wheels have two upstanding flanges '56 thereon which define the outer boundary of two paths; or tracks 58 for the drive members hereinafter described. Each path extends approximately one-half the. width of the space between the flanges 56 and is generally equal to the width of the flexible drive members wheel 47 to complete hereinafter described. The paths preferably have a series of generally equally spaced slots or recesses 60. The

actuator 34. Each of the flexible drive members shown' herein are belts having a smooth surface 70 on one side and a series of generally equally spaced teeth 72 on the other side which willmate withthe equally spaced slots 60.

Hereinafter I will use the terms weight and wheel interchangeably and the term weigh may be thought of as including both the wheel and the mass'or weight maintained on the wheel.

As the weights aremounted for independent rotation, it will be seen that weight 66 on actuator 34 will be driven in a predetermined direction, for example that shown by the arrows, by belt 64 and pulley 32. A second flexible drive member 76 may be positioned around outside path 78 on weight 66 and on outside path 80 formed on weight 82 of .actuator36 to drive weight 82 inthe direction of.

The direction of vibra- A suitable cap or the like 55 may be conthe direction of the arrows. The driving connection between the pair of actuators is completed by a second belt 84 which is positioned on inside path 86 on outside weight 88 of actuator 36 and on the inside path 90 formed on weight 92 of actuator 34. The driving means, as thus far described, show means whereby the rotation of weight 66 drives weight 82 through belt 76. Belt 84 provides a connection between weights 88 and 92 so that they will be driven in the same direction.

FIGURE 2 shows the details of the reversing means whereby the rotational motion of weight 82 is given to weight 88, but in an opposite direction. Spaced, freely rotatable, idler pulleys 94 and 96 are suitably mounted by means of a bracket or plate 98 on plate 16 adjacent actuator 36. The idler pulleys each have a generally

central channel

100 and 102 respectively formed by spaced flanges 104 and 106 to provide a path for the flexible drive member hereinafter described. As shown in the drawings, the idlers have a smooth channel surface to receive the flexible drive member although it may be otherwise, for example, the channel surface may have teeth or grooves. The idlers are preferably disposed at a slight angle to the vertical to provide a more compact sructure. A flexible drive member 108 which is usually the same as the flexible drive belts heretofor described connects both of the idlers and the two weights on actuator 36. In order to better understand the reversing assembly shown herein, the path of belt 108 will be traced starting at weight 82 and returning thereto. Belt 108 is positioned on weight 82 on inside path 110 and as the belt leaves the bottom of this weight it is rotated or twisted through 90 degrees so that it may be wound around idler 96 which rotates at an angle of 90 degrees to the plane of rotation of the actuators. From idler 96 the belt is against twisted or rotated through 90 degrees and then placed on outside path 112 on weight 88. The belt will travel on weight 88 through 180 degrees after which it will run to idler 94, again after being twisted or rotated through an angle of 90 degrees while passing between the weight and the idler. The belt moves around idler 94 and then returns, again after being rotated through 90 degrees, to weight 82. From the above description of the reversing mechanism it can be seen that a single flexible driving member or belt and two spaced, freely rotating, idler pulleys provide a means whereby the inside weight of actuator 36 drives the outside weight, but in the opposite direction.

FIGURE 4 shows a modified form wherein provision is made for varying the direction of vibration of the rotating weights. The plate 98 mounting the idlers 94 is not mounted directly on plate 16, as was the case in FIGURE 2, but may be secured to a rotatable plate 120. In the alternative, the idlers may be mounted directly to the rotatable plate 120. In any event, the plate 120 is rotatable about the axis of the actuator 36 and is held in any angular position by a bolt or the like 122 extending from plate 16 through an arcuate slot 124. By changing the angular position of the plate 120 and so the angular position of the weights, the points of coincidence of the weights are varied, thus changing the direction of vibration of actuator 36.

The use, operation and function of the invention are as follows:

Shown and described herein is an improved means for imparting straight line or elliptical vibratory motion to a screening assembly or the like. Each of the actuators used herein include rotating weights which may be equal or unequal and which revolve in opposite directions and have points of coincidence and opposition 90 degrees apart. The points of coincidence may form a straight line which is the direction of vibration of the actuators, or if the weights are unbalanced the motion may be elliptical. In any such screening assembly it is necessary to provide a simple and eflicient method of driving the actuators so that the weights are properly rotated. In-

stead of the conventional gears, pinions, etc., which have been used in the past to provide the driving means for such oppositely rotating weights, shown and described herein is an improved driving means including flexible driving members which may be belts, chains, or other wise. Also shown is a reversing assembly including two spaced idlers and a belt positioned therearound which rotates the weights in opposite directions. As a screening assembly is conventionally used to screen, sort, or grade minerals or ore it is necessary to have a system for driving the screen which will not easily clog or become inoperative when small particles become embedded in the machinery. The cog-belts or other flexible driving means shown herein will have an extremely long life and are highly wear-resistant.

In the operation of the driving means one of the weights on one actuator, which may be either the inside or outside weight, is driven by a conventional driving pulley. A second belt runs around the same weight and around the corresponding weight on the other actuator. Therefore, the corresponding weight on the second actuator will be driven at the same rate and in the same direction as the weight being driven by the driving pulley. Another belt, positioned on the driven weight on the second actuator, is wound around two spaced, freely rotating idler pulleys and the other weight on the second actuator. The belt is rotated degrees as it passes between an idler and a weight as the idlers rotate in a plane forming an angle of 90 degrees with the plane of rotation of the weights. The idlers then provide a means for reversing the direction of movement of the weights so that the second weight, which as shown herein as the outside weight, but may be otherwise, of the second actuator rotates in the opposite direction from the first weight on the actuator. As the second weight or outside weight, rotates in the opposite direction, and as it is connected through a second belt back to the first actuator, both actuators have weights rotating at the same speed and in opposite directions.

As shown in the drawings, the belts may have equally spaced teeth formed thereon which mate with equally spaced grooves formed in the outer periphery of the weights. This is the preferred form of drive member although a chain is also satisfactory. It should be noted, that when the belt passing around the idlers is rotated through 90 degrees the surface of the belt having the teeth is on the outside of the idler and does not contact the idler surface. This prevents wear on the teeth and provides smoother operation.

Whereas the driving means has been generally described as comprising a pair of actuators along each side of the screening assembly it should be realized that a third actuator may be positioned on each side and the now second actuator would become the center actuator. The third actuator would then have the reversing mechanism associated therewith. In the same manner, a fourth or fifth actuator may be driven through the same mechanism. By the same token, if there is only one actuator, the reversing means shown herein would be positioned next to the first actuator to provide a means of driving the weights thereon in opposite directions.

As has been described, the counter-rotating weights provides straight line vibratory motion. The direction of this vibratory motion may be varied by positioning the weights so that the points of coincidence, although remaining under 180 degrees apart, are at different circumferential positions. As shown herein, once the weights have been set for a certain direction of vibration, this direction remains the same during operation. However it is possible to provide means for rotating the points of coincidence of the weights during operation so that the direction of vibration may be correspondingly varied. For example, as shown in FIGURE 4, the plate may be rotated about the axis of the actuator either during operation of the screen or while the machine is 7 at rest. Rotation of the plate 120 and hence the idlers change the points of coincidence of the weights and so the direction of vibration. It is also possible to use weights of unequal size on adjacent wheels thus producing elliptical motion whose long axis will respond to variation the same as for weights of equal size.

Whereas the preferred form of the invention has been shown and described herein it should be realized that there are many modifications, substitutions and alterations thereto within the scope of the following claims.

I claim:

1. A screening assembly or the like including a screen and two adjacent actuators secured thereto, each actuator including a pair of weights mounted for opposite rotation about a common shaft secured to the assembly, the forces produced by the revolving weights alternately complementing and opposing each other every 90 degrees, the outer surface of each weight being formed into two parallel tracks, means for rotating the weights including two flexible drive members each of which is positioned in a track on a weight of one actuator and a track on a weight of the other actuator to simultaneously rotate said weights in the same direction, said two flexible drive members moving in opposite directions and in parallel paths, power means for rotating a weight on one actuator in a predetermined direction, and a flexible drive member positioned in a second track of both weights of the other actuator and arranged to drive said last-named weights in opposite directions.

2. The structure of claim 1 further characterized by two spaced freely rotatable idler members positioned adjacent said other actuator, the flexible drive member connecting both Weights of said other actuator moving in a path from one weight around an idler, around the other weight, and then around the other idler and back to said first weight, said flexible drive member being rotated through degrees while passing between a weight and an idler.

References Cited in the file of this patent UNITED STATES PATENTS 2,144,382 Lincoln Jan. 17, 1939 2,831,359 Carle Apr. 22, 1958 2,865,210 Fisher Dec. 23, 1958 2,994,431 Becker et a1 Aug. 1, 1961 FOREIGN PATENTS 411,191 Great Britain June 7, 1934 550,015 Germany Apr. 21, 1932 729,933 France May 3, 1932 976,918 France Mar. 23, 1951