US2274701A - Screening apparatus - Google Patents

Description

March 3, 1942; c. E. JENKS 2,274,701

SCREENING APPARATUS Filed March 13, 1939 INVENTOR. Curran E. JEN/(5.

Patented Mar. 3, 1942 T QFFICE 2,274,701 SCREENING APPARATUS Clifton E. Jenks, Willoughby, Ohio, assignor to The W. S. Tyler Company, Cleveland, Ohio, a

corporation of Ohio Application March 13, 1939, Serial No. 261,560

3 Claims.

This invention relates, as indicated, to screening apparatus for wet or dry bulk materials and the like, but has reference more particularly to apparatus of this character in which the screens are mechanically or otherwise subjected to a gyratory movement.

Where fine screens are used in apparatus of the aforesaid character, such screens, unless supported in asuitable manner, are liable to becom' stretched as a result of continued usage, particularly in screening materials of high specific gravity, and therefore requires frequent replacements.

Moreover, where such fine screens are employed in screening wet materials, a film of water is formed, which adheres to the lower surface of the screen and which interferesto a considerable extent with the screening operations.

It is a primary object of the present invention, accordingly, to provide means for preventting the stretching of screens used in the fore going manner and to incorporate in such means a material which will not itself be too rapidly abraded by the screen itself or by the materials to be screened.

Another object of the invention is to provide means for this purpose which will not materially affect the screening action or efiiciency of the screens.

A further object of the invention is to provide I means which will aid in breaking up films of water adhering to the screens which interfere with the screening operations.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the annexed drawing and the following description setting forth in detail certain structure embodying the invention, such disclosed means constituting, however, but one of various means in which the principle of the invention may be used.

In said annexed drawing Fig. 1 is a plan view of screening apparatus embodying the device of the present invention;

Fig. 2 is a side elevation of the apparatus shown in Fig. 1;

Fig. 3 is a transverse cross-sectional View of the apparatus, taken on the line 33 of Fig. 1; and

Fig. 4 is a longitudinal cross-sectional view of the apparatus, taken on the line 44 of Fig. 1.

Referring more particularly to the drawing, it will be seen that the apparatus comprises a pair of spaced side plates or channels I and 2, be-

iii)

(Class 209-403) tween which a screen 3 is disposed. The screen is curled at its marginaledges to provide upwardly directed curved flanges 4, which are bound with taping 5 formed of strips of sheet metal.

' The screen is maintained under tension by means of stretcher-strips 6, which engage the inner surfaces of the flanges 4, or rather engage the taping 5 which binds these flanges. Each of the stretcher strips is secured to its adjacent side plate by means of bolts I and nuts 8.

The apparatus which has been described is adapted to be gyrated or otherwise vibrated by means of mechanism which is not shown, but which is well understood by those skilled in the art to which the invention relates.

For the purpose of resiliently supporting the screen 3 in a desired manner, so as to prevent undue stretching thereof, and for other purposes to be presently noted, a screen support is provided, which will now be described. I

This support comprises a panel or frame consisting of sides 9 and ends I0, this frame being substantially coextensive in area with that of the screen. Extending'between and secured as by welding to the ends ID of the frame at points spaced transversely of the frame are members, each of which consists of a pair of 2 bars, the

lower flanges II of which are spot welded or otherwise secured together and the upper flanges I2 of which are spaced apart to provide a recess or groove for the reception of a strip I3 of felt or similar soft and resilient material. The members III2 are of substantially the same height as the sides 9 and ends II], but the strips I3 project somewhat above these members, and bear against the lower surface of the screen 3, slightly bowing the screen, as clearly shown in Fig. 3.

Intermediate the members II-I2 andsecured as by welding the ends thereof to the ends Ill of the frame is an angle member I4, having a horizontal leg I5, which is co-planar with the top of the frame 9I0, and to which is secured the longitudinal central portion of the screen -3. In thus securing the screen to said angle member I4, a strip of felt I6 is first disposed on the leg I5, and a similar strip I! of felt is laid on the screen, after which a metal strip I3 is laid over the strip II. Bolts I9 are then inserted through the strips I6, I! and I8 and into nuts 20 which are welded or otherwise secured to the under surface of the leg I5 at spaced points.

Extending between and welded to the sides 9 of the frame and the members II-I2 at points spaced longitudinally of the apparatus are crossmembers, each of which consists of a pair of Z bars, the lower flanges 2| of which are spot welded or otherwise secured together and the upper flanges 22 of which are spaced apart to provide a recess or groove for the reception of a strip 23 of felt or the like. The strip 23 projects somewhat above the recess or groove and its upper edge slopes to conform with the inclination of the screen resulting from the bowing of the latter by the strip l3. V

Extending between and welded to the members lll2 and the member [4 at points in aligmnent with the members 2l22 are similar cross-members, each of which consists of a pair of 2 bars, the lower flanges 24 of which are spot welded or otherwise secured together and the upper flanges 25 of which are spaced apart to provide a recess or groove for the reception of a strip 26 of felt or the like. The strip 26 projects somewhat above the recess or groove and its upper edge slopes to conform with the inclination ofthe screen resulting from the bowing of the latter by the strip l3, it being noted that the upper edge of the strip 26 is inclined oppositely to that of the strip 23.

It is to be noted that the support, consisting of the elements 9, In, ||--l2, l4, 2l22 and 24-2 5, is aunit which may be removably secured to the side plates l and 2 in any desired manner, and that the felt strips are individually removable from their recesses. This enables any strip to be removed for replacement purposes without disturbing the remaining strips.

It is also to be noted that the felt strips provide a resilient support for the screen, and that the screen is supported at a sufficient number of judiciously spaced points to prevent the screen from becoming stretched during gyration of the apparatus.

It should also be noted that the felt strips are spaced apart sufficiently so as not tomaterially decrease the screening efficiency of the apparatus.

The felt strips, being to a great extent water absorbent, are effective to break up films of water which adhere to the lower surface of the screen, and which interfere, to a large extent, with the screening operations.

Due to the bowing of the screen by the felt strips I3, 23 and 26, the felt strips are compressed to a slight extent, and this compression.

is sufiicient to cause the individual wires of which the screen is composed to slightly embed themselves in the soft surface of the felt strips. In this way, the entrance of the materials being screened into spaces or crevices between the screen wires and the felt strips is precluded, and this source of abrasion of the screen and strips eliminated.

Instead of felt, other'soft, resilient, abrasionresistant materials may be employed for the screen-supporting strips, such, for example, as sponge rubber, asbestos compositions, etc. Moreover, the spacing of the felt strips may be varied within wide limits, providing the screening operations are not interfered with by the strips being too closely spaced or the screen support is not reduced to an undesirable extent by too wide spacing.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the structure herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. Screening apparatus comprising a screen frame, a screen extending across said frame, means for maintaining said screen under tension, and means independent of said first-named means for resiliently supporting said screen, said supporting means comprising a frame disposed within said screen frame below said screen and having recesses in its .upper portion and strips of a resilient material disposed in said recesses and extending above said recesses and into engagement with the lower surface of said screen.

2. Screening apparatus comprising a screen frame, a screen extending across said frame, means secured to said frame and maintaining saidscreen under tension, and means independent of said first-named means for resiliently supporting said screen, said supporting means comprising a frame disposed within said screen frame below said screen and consisting of members spaced transversely and longitudinally of said supporting means and having recesses therein, and strips of a resilient material disposed in said recesses and extending above said .recesses and into engagement with the lower surface of said screen.

3. Screening apparatus comprising a screen frame, a screen extending across said frame,

means secured to said frame and. maintaining said screen-under tension, and means independent of said first-named means for resiliently supporting said screen, said supporting means comprising. a frame disposed within said screen frame below said screen and consisting of members spaced transversely and longitudinally of said supporting means, each of said members comprising a pair of Z bars having flanges thereof secured to each other and flanges spaced apart to provide a recess, and strips of a resilient material disposed in said recesses and extending above said recesses and into engagement :with the lower surface of said screen.

1 CLIFTON E. JENKS.

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