US1308998A - Screen - Google Patents

Description

A. L. AND J. M. STONE.

SCREEN.

APPLICATION FILED APR.19, ma.

1,308,998. v Patented July 8, 1919.

' ATTORNEY 55 capable of moving parallel withand angu- AVON L. sworn: AND JOHN s'ronn, or LODI, CALIFORNIA.

SCREEN.

Specification of Letters Patent.

PatentedJuly 8., 1919.

Application filed April 19, 1918. Serial No. 229,615.

ments in Screens, of which the, following is a specification.

This invention'relates to grain separators, and more particularly to the separating screens thereof, aiming primarily to provide improvements upon separating screens of 'the general character illustrated inthe patent granted to John M. Stone, October 41th 1910, #971,701.

A further object of the invention is to provide a screen so constructed as to. obtain the highest degree of vibration in the wires thereof, whereby the efficiency of screens of this character is greatly increased.

A further object is to provide a screenineluding a frame of simpleconstruction and possessing great strength, and which is equipped withsuch improved means for at taching the wires to the ends of the frame as will permit of the various strands of thewire being stretched at equal tension, and which automatically distributes the slack or'loosen'ess occurring in any one strandfev'enly. to all of the strands, thus greatly reducing the opportunity for breakage of the wires.

Further objects and advantageswill-ap pear hereinafter. i l

In the drawings Figure 1 is'a lan view of a screen con.- structed in accor ancewith the invention,

Fig. 2 is an enlarged longitudinal sectional view of the screen taken substantially upon line 22 of Fig. 1, and

upon line 3 3 of Fig. 1. t

In carrying out the invention, we provide a frame constituting side and end bars formed preferablyof metal, and disposed at, right angles to each other. The end members of this frame support the ends of the wire strands which coverthe frame, and thebearing surfaces provided by these end members are extremely narrow soas' 'to minimize the area of contact of the wires withthe bearing surface, and yet these surfaces-are not so narrow as to out orinjure the wires; Each of the end members is provided with a stretching or tensioning rod, and. these tensioning rods are rotatably supported and Fig. 3 is a transverse sectlonal view taken larly toward or away fromthe bearing surfaces. Hook bolts or other suitable securing elements are engaged with the tensioning 'rods,and'are capableof being'minutely adjusted 'so as jtojcontrolthe -movement of the rods. The hook boltsor'securing elements are constructed in such manner as not to permit ofthe ro'ds'moving' into the same plane'with the adj acent'bearing surfaces, so thatthe high degree of vibratory action or the strands caused by stretching the same across the restricted bearing surfaces will not be impaired or destroyed. It is preferred that a single wirebe' used for the screen, and this wire is crossedjback and forth across the frame and the bearing surfaces thereof, and around the tightening rods at the ends of the frame. By loosely extending the wire around the tensioning rods, the various strandsare capable ofad- -justing "themselves longitudinally .of the frame, whereby uniform tension in all of the strands is established andImaintained. In order that the variousfstrands may be spaced apart 3 an equal distance throug'hout the width of the frame and to maintain the strands so positioned, the bearing surfaces at'the endsv of the" frame'm'ay be provided with shallow notches to receive the strands. 1 -As the frame is formedof metallic bars there'is a greater orless'amountof resili ency therein, and when 'thesecuring elements for the tensioning bars are moved so asto stretch the strands tightly across the frame, the latter is bowedslightly, and the tendency of the frame to fstraighten or assu'me normalor relaxed position causes the various strands to possess the requisite ten:- sion.

Referring now more particularly to the drawings, 5 indicates the longitudinal or side bars of the improved frame, whichbars are connected at their extremities by the end barsindicated at 6;" The side'bars'5 are preferably made of T iron as shown in Fig. 3, and the upstanding portions of these irons are cut'and bent inwardly atthei'r extremities to provide retaining feet 7 to which the end members 6 are connected. The frame also includes a reinforcing or strengthening bar 8, disposed in spaced parallel relation to v which are secured by bolts 9 to the bottom portions of the longitudinal members 58, while the upstanding portions of the L-irons are bolted as at 10 to the retaining feet 7 of the longitudinal members. By constructing the frame in this manner it is obvious that the latter will be capable of withstanding the strains to which the same will be subjected when the Wires are tightened, and such strains are equally distributed to all parts of the frame.

Each of the end bars 6 is provided with means for supporting and tensioning the wires which cover the frame, and this means includes cylindrical tensioning rods 11. These rods are arranged parallel to and slightly beyond the upper edges of the end members 6, and are below the horizontal plane of the said edges. The rods 11 are confined within the hook ends 12 of the bolts 13, the threaded ends of the said bolts being extended through the horizontally disposed portions of the L-irons 6, and the said threaded ends are equipped with nuts 14 to enable the said bolts to be adjusted. The portions of the end members 6 through which the bolts 13 extend are bent angularly as shown in Fig. 2 of the drawings, and the bolts 13 are thus capable of moving angularly across the end members. By tightening the nuts 1a the bolts will be drawn downwardly, bringing with them the rods 11, and this downward movement of the rods causes the wires indicated at 15 to be tensioned. When the nuts 14. are loosshed, the strain of the wires 15 causes the rods 11 to move upwardly and inwardly, but it will be observed that the hook ends 12 of the bolts will engage the upstanding portions of the members 6 before the rods 11 move into the same horizontal plane with the upper edges of thesaid L-irons. By so constructing the device, the wire strands 15 are always tensioned between the bearing surfaces on the end bars 6 so that the vibratory action of the strands cannot be impaired. 1

It is preferred that the bearing surfaces provided by the members 6 be very narrow so that the actual surface contact between the strands and the supporting surface will be small. This bearing surface is provided with anumber of grooves of shallow depth, spaced apart the desired distance and in which the wire strand rests. By thus grooving the bearing edges of the end members, the strands will be prevented from moving toward or away from each other and will at all times be maintained in proper spaced parallel relation.

a The frame is strung preferably with a single wire, secured at one corner of the frame to the tensioning rod 11 and passes upwardly therefrom and over the adjacent bearing su fa e to the orpesi e end. a th The wire is then passed around the tensioning rod at the said end and then back to the opposite end of the frame. The continuous strand is thus woven back and forth across the frame until the latter is entirely covered, and the end of the wire may then be secured to the tensioning rod adjacent which it is disposed. The strands are then tensioned by operating the nuts 14:, and by reason of the fact that the strands pass loosely around the tensioning rods and as the latter are rotatably supported within the hook portions 12, an even tension in all of the strands is established and maintained. By this particulararrangement, the various strands are capable of automatically adjusting themselves, whereupon the strain throughout the frame and upon all of the wire strands is equalized, and danger of overstraining some of the wires or break ing of the latter is exceedingly remote. By reason of the fact that the frame is formed of metallic bars, the same will be slightly bowed when the wires are tensioned, and the elasticity in the frame tends to maintain the wire strands at the requisite tension.

While the present is a disclosure of the preferred embodiment of the invention, it is to be understood that the invention is not limited thereto, as variouschanges in the minor details of construction, proportion, and arrangement of parts may be resorted to if desired without departing from the spirit of the invention as defined by the appended claims.

We claim 1. In a grain separating screen, a frame having bearing surfaces at each end, hook bolts at the ends of said frame capable'of moving angularly toward or away from said surfaces, cylindrical bars loosely inclosed by said hook bolts and disposedparallel with and below the plane of said hearing surfaces, nuts on said bolts for adjusting the latter, and strands covering said frame and resting at their ends upon said surfaces and passed around said bars.

2. In a grain separating screen, a frame having parallel end membersformed of angle bars, the ends of the upstanding por. tions of said bars forming bearing surfaces, retaining elements supported by the other of said portions and capable of moving angularly toward or away from the first mentioned portion, cylindrical rods rotatably carried by said retaining elements and disposed parallel with said bearing surfaces, and strands covering said frame resting at their ends upon said surfaces, and engaged saidbolts having hooks, wire strands ex- In testimony whereof we afiix our signatending between the said L lI'OIlS and tures in presence of two witnesses. mounted upon the edges of the Vertical pora AVON L. STONE. tlons of the sald L-lrons, tenslonmg rods carried by the said hooks and attached to JOHN STONE the said wire to tension the wires when the Witnesses:

said bolts are adjusted in the said angularly DAN W. BIRD,

bent portion of the L-irons. L. H. Rnm.

Copies otthis patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G."

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