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Publication numberUS1563173 A
Publication typeGrant
Publication dateNov 24, 1925
Filing dateMay 8, 1924
Priority dateMay 8, 1924
Publication numberUS 1563173 A, US 1563173A, US-A-1563173, US1563173 A, US1563173A
InventorsDoerres John H
Original AssigneePennsylvania Crusher Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Coal breaker or crusher
US 1563173 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Nov. 24' 1925;


'Irukrdofi Patented N my. 24, 192 5. 7 NITED STATES PATENT OFFICE.

JOHN H. DOERRES, or sr. LOUIS, mrssouar, ASSIGNOR To PENNsYLvANiA cnusunn comrany, or NEW-YORK, N. Y., A conroaa'rron or new YORK. 1 u

COAL BREAKER on cnusnim.

Application filed May 8, 1924. Serial No. 711,778.

To all whom it may concern."

Be it known that L'JOHN H. DOERRES, a citizen of the United'States, and aresident of the city of St. Louis, Missouri, have invented certain new and useful Improvements 1n Coal Breakers or Crushers, of

which the following is-a specification.

' calcage or screen made up of longitudinal f m'emberssupported by end rings attached to central hubs by suitable spokes, and

screen .plates which are secured to said longitudinal members. These structures are .of very large size and the amount of material passing through the same is such that the screen plates under normal screening conditions are subjected to tremendous strains and stresses due to the weight of the falling material undergoing crushing and screening.

One object of my invention is to provide an improved form of screen plate having an increased area of contact with the supporting means therefor, and a further object of my invention is to provide improved means for securing the screen plates to their supporting members.

These and other features of my invention are more fully described hereinaftemreference being bad to the accompanying draws, in which:

igure 1,, is a cross sectional view of a 'Bradford breaker or crusher, showing the use of my improved screen plates: and the manner of mounting them with respect to their supporting members in accordance with my invention.

Fig. 2, is a perspective view of one of my improved screen plates. Fig. 3,'is a fragmentary SGCtlOIlfllVlGW on alargerscaleillustrating in greater detail the manner in, which my improved plates are secured to the longitudinal supporting ture, and w Figs.-4= and 5, are sectional views illustrating modified details of construction within the scope of my invention.

My present improvements relate to the character of the screen plates; the manner of mounting: them with respect to'the longimembers of the breaker or crusher structudinalsupporting members, and the man- 7 ner ofsecuring thesame thereto.


In the former practice the foraminous plates employed in making up the screen drum, usually perforated plates, have been mounted on the longitudinal supporting members withtheir meeting edges abutting 1n lines substantially parallel with the longitudinal axis of the screen drum. The longitudinal supporting members were usually I- 'shape in cross section, and the plates were secured in place by bolts or rivets passing through apertures adjacent to the edges-of the same and through apertures in the flanges of said longitudinal members, .Ad-

ditionally, the abutting plates heretofore employed were curved on the arc of a circle struck from the axis of rotation of the screen 1 in line but are spaced apart and approximate a cylindrical wall to which the several screen plates are secured.

The screen plates forming the subject of" my invention and which I propose to employ'to make up the screen drum are rectangular and flat. They may be of any suitable length longitudinally of the drum and circumferentially are of an extent equaling the distance between the flanges of any pair of the longitudinal supporting The edges or edge portions of said plates for engagement with said longitudinal members are bent to conform to the angle the supporting flange portion thereof presents with respect-to a straight line ex-. tending from flangeto flange of two of said longitudinal members.

In addition, the screen plates are so mounted with respect to the longitudinal supporting members that the bent. edges, or what may be termed the flanges of the successiveplates overlap each other circumferentially of the drumand are secured in place by bolts or rivets passing through two thicknesses of lapped plates and through the flanges of the longitudinal supporting members of the frame; thereby providing a better anchorage for the plates than is possible with theiormer construction.

Inthe drawings, 1 represents one of the trunnions of a breaker or crusher structure of the Bradford type, to which a spider comprising a hub 3, radiating spokes 4, and a circular head structure 5, is connected; a similar arrangement being provided at the opposite end of the screen drum. The trunnions may be supportedin suitable bearings 6, and these bearings may be hung from beams or girders 7, (one of which is shown), supported in any suitable manner.

Extending longitudinally between the head members 5, which may be in the form of truncated cones, are longitudinal supporting members 10, to which the screen plates 11, are secured, and the ends of these supporting members 10 may be secured to socket plates 12, suitably secured to said headv structures 5, or said socket plates may be formed integral therewith. The longitwdinal supporting members 10 may be of I- shape or other suitable cross section with the web set radially with respect to the axis of rotation, and it is to the inwardly disposed flanges 10 of said longitudinal supporting members that the screen plates 11 are secured. The surface of these flanges is normal to the axis of rotation, or at right angles to planes passing through the axis of rotation, and in such relation each adjacent longitudinal member has a surface disposed at an oblique angle with respect to the others,

, and so on throughout the cylindrical portion of the screen structure.

The screen plates, indicated at 11, may be of any convenient size, usually about 30 square, and provided with perforations 11*,

whose size is dependent upon the work the screen is to accomplish. 7 These plates are flat throughout their screening extent with slightly turned edge portions or flanges 11*,

whose angle with respect to the flat surface of the major portion of the screen plate accords with the angle of the flanges of the supporting members to which said plates are secured.

These screen plates are so mounted and sevcured to the longitudinal members 10" that each succeeding plate overlies or underlies the preceding one to the extent of the flanges of thesupporting members to which they are secured. The flanges 11 of each plate are provided with two rows or sets of holes 13 for the passage of securing means, which may be in the form-of rivets, or headed bolts 14, secured by nuts 14 and lock nuts 14"; spring washers 14 being preferably interposed between the nuts'I4 and the flangesof the supportin in Fig. 3.

through two plates and the flan supporting members 10, it canv readily members, as clearly shownv 5 these securing bolts pass: of the seenthat a very rigid construction is provided.

I have shown in Figs. 1, 2 and 3, flat plates 11, with bent edge portions forming flanges 11 the flange of one plate overlying the preceding or succeeding plate, as the case may be, when such plates are assembled to form the screen drum, and such overlying portions being disposed above the plane of the underlying plate. While this arrangement may be preferred in some instances, I have illustrated in Figs. 4 and 5 modified forms of screen plates having one edge joggled, as indicated at a; and m, respectively, such edge portion or flange being offset or recessed to such an extent that the plates when assembled will provide a drum having a substantially smooth inner surface.

In Fig. 4, I have illustrated a plate 111, with one edge a", offset or recessed with respect to the plane of the major portion of its surface and receiving the edge flange 11 of the succeeding plate. In Fig. 5, substantially the same arrangement is shown except that the plates 111*, which have one edge 00 oiiset or recessed, are curved on the arc of features which may be summed up as follows: v

The ends of the screen plates are held in plaoeby two setsof securing members and the plates act as a continuous beam, circumferentially of the drum. Such arrangement prevents bending of the plates as well as any leverage action on-the securing bolts and eliminates any tension on the bolts which 1 would tend to loosen them. 'As the bolts are under double shear, instead of single shear and tension, more than twice the strength is added to each bolt. While no more bolts are required with my arrangement over the prior construction, each screen plate is secured in place by twice the number of bolts heretofore employed in securing the screen plates in breaking or crushing structure of this type; v

This condition, together with the change in stress on the bolts materially reduces the strain on each bolt. Any shearing action on the supporting members cause l by the bolts is toward the centre of the same instead of 9 toward the outer edges, and it isimpossible for the bolts 'to tear any holes through the flanges of said supporting members. As the overlapping of the plates makes a practically continuous beam around the breaker drum; very little anchorage to the support- 6. ing members is actually -required: in other 15 and from the plane of the main body of the words, the flat screen plates could be bolted together independently of the'longitudin'al supporting members and still provide an efficient screen structure.

I claim: 7

1. The combination, in 'a coal breaker, ot a screening drum comprising a seriesbf substantially flat screen plates having edge portions in flat planes diflering from each other plate; said edge portions being arranged in overlapping position, and means for securng the overlapping portions of said plates together. l t

2. The combination, in a coal breaker, of a series of substantially flat screen plates disposed circumferentially and forming a screening dru1n, said plates having edge por-' tions in flat planes diifering from each other and from the plane of the main body of the plate with said edge portions in overlapping position, and meansfor securing said plates together at their overlapping portions.

{ The combination, in a coal breaker, of a screening drum comprising longitudinal supporting members, and substantially fiat screen plates having overlapping, flanged edges secured to said longitudinal supporting members. i

l. The combination, in a coal breaker, of

a screening drum comprising longitudinal .supportingmcmbers, and a series of screen plates secured to. said longitudinal supporting members; said screen plates being substantially flat and having edge flanges overlapping each other circumferentially of the drum with the securing ,means passing through said overlapping portions.

5. The combination, in a coal: breaker, of a screening drum comprising longitudinal supporting members, end supports for the same, and substantially flat screen plates having overlapping edge flanges secured to said longitudinal supporting members circumferentiall of said drum. v

6. The com ination, in a coal breaker, of

a screening drum comprising a series of longitudinal. supporting members and a series of flat screen plates having edge flanges in engagement with the longitudinal supporting members; said flanges having a width substantially equal to the engaging I surface of the longitudinal supporting mem bers and overlapping each other at the point of engagement, with securing means passing through said overlapping plates and the the longitudinal supporting members and w overlapping each other at'the point of engagement therewith, and a plurality of securing members passing through said overlapping plates and the flanges of said \supporting membbrs.

In Witness whereof I have signed this specification.

JOHN H. nonnnns.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2575484 *Sep 9, 1949Nov 20, 1951Borton George WSupport structure for screening cylinders
US2692087 *Oct 1, 1951Oct 19, 1954Pennsylvania Crusher CoWall plate structure for drum type breaker mills
US2710150 *May 22, 1953Jun 7, 1955Bath Iron Works CorpScreen plate and mounting
US5021150 *Jan 17, 1990Jun 4, 1991Buerklin WernerSieve drum for sieving out waste or the like
U.S. Classification241/91, 209/298, 209/288
International ClassificationB02C17/00, B02C17/02
Cooperative ClassificationB02C17/02
European ClassificationB02C17/02