US2586122A - Gyratory crusher - Google Patents

Description

Feb. 19, 1952 s. w. TRAYLOR, JR 2,586,122

GYRATORY CRUSHER Filed Feb. 6, 1948 2 SHEETS-SHEET l /7 I Shawn tom Samuel (71113101702- Feb. 19, 1952 S. W. TRAYLOR, JR

GYRATORY CRUSHER 2 SHEETSSHEET2 Filed Feb. 6, 1948 Patented Feb. 19, 1952 UNITED STATES PATENT OFFICE GYBATORY CRUSHER Samuel William Traylor, J r.,' Allentown, Pa.

Application February 6, 1948, Serial No. 6,633

12 Claims. (Cl. 241209) The present invention relates to crushers for mate'rialsuc-h as rock and ore. More particularly, therinvention constitutes. improvements in gyratory-crushers in. which crushing. heads. having. mantels supported thereon are given gyratorymotion withrespect-to downwardly facing concaves.

A primary object of the invention is to reduce theoverall height: of such. crushersand to supportwthe gyratory shaft from its lower end, in-

stead of hangingthe shaft in an upper bearing from above. In many crushers of the. gyratory type, the gyratory shaft-which carries the crushing head and mantelis suspended by bearings having sphericalsurfaces, in a spider carried. by the upper'frame section-and the lower end of the shaft is mounted, without bottom support, in theinterior cfa rotatable eccentric, by which gyratorymovement isimparted to. the shaft and head. Althoughsuch crushers have. beenfound entirely satisfactory inuse, numerous. adv-an.- tagesflow in. many cases from a construction. in accordance withi the. present invention, in which the length of the shaft is. reduced and the shaft supported in a novel manner. from below, with- I in the eccentric. 1

A further object of the. invention is to provide improved .antiefriction bearing means forsupporting a gyratory crusher shaft. in. the eccentric. Another object is to provide improved anti-friction bearing .means fror supporting the eccentric itself...

.Another object is to provide improved structural .features associated with the. support, or guiding means for the upper end of. the gyratory shaft. to theend that this portion .of the shaft may have. universal movement about a central pointofnomotion Another objectis to .provi'dean improvedconnection between the upperframasecti'onof the crusher andthe, bearing means for: the upper end of the shaftlto the. end that the upper frame may be-adiusted vertically with respect to thelower frame, andcthecrusher head, to adjust the space between the downwardly facing concave, carried by the upper frame section,,and' the upwardly facing crusher head,, s l.Pported by the lower framesection.

-A further object of the invention is to, improve. the lubricating system. of. a gyratory crusher. More specifically, the .inventionaims to provide an. improved oil cooling system, including means forpositiv'ely circulating the .oil in heat exchange. relation to cooling coils, through which a cooling medium ispositiyely circulated.

ings, in which,

Figure 1 is a vertical section and partial elevation ofacrusher;

Figure 2 is an enlargedvertical section'showin'g the supporting means for the lower end of the shaft;

Figure 3 is a horizontal section on line 3-3 of Figure 2, and l Figure 4 is a sectional detail taken on-line 4-4 of Figure 3.

The crusher includes a fixed lower frame or casing Ill, including a heavy cylindrical section II terminating at its lower end in an outwardly projecting, supporting flange l2. 'A plurality of inwardly extending webs l3 join a'top housing section I' l having an upwardly projecting, centrally arranged hub I5. A lower or bottom housing section l6 may be bolted or otherwise secured to the housing M, with an inwardly projecting annular plate or ring H interposed, for purposes hereinafter described.

The upper portion of the outer surface of the cylindrical section I I of the fixed lower frame or casing in is shaped to provide a heavy screw thread [8, upon which a cylindrical member [9, 4

constituting a part of the upper frame section 20., is supported for vertical adjustment by relative rotation. with respect thereto, the member t9. having a, complemental screw thread 2| formed .on its inner circumference, .A locking ring 22, disposed below the cylindrical member I9, serves to secure the parts, in adjusted position. The upper frame section. i9 is shaped. to provide an upper, outwardly turned annular flange 23, upon which is mounted-a ring 24,, constituting aseat for a plurality of inwardly projecting arcuate: members 25-, each having an upwardly and inwardly inclined flange 2:6 upon which the backing-21' is'mounted. The backing 2'1 and its supporting-meansv may be constructed substantially as shown and described in mycopending application Serial No. 743,078, filed April 22, 1947, which matured into Patent No. 2,550,098

on April 24, 1951, and may support the concave 28 by means of pins 29, engaged by hooks 30 integral with the concave and extending upwardly through appropriate openings in the holder, as there described.

The upper frame further comprises an upper cylindrical section 3|, having lower and upper outwardly projecting flanges 32 and 33, the former being seated upon the arcuate members 25 and secured in place by bolt and nut assemblies 34, extending through the flange 23, the ring 24, the arcuate members 25 and the flange 32.

The upper flange 33 serves as a support for an inwardly projecting, annular cover casting or spring cage 35, held in place by tie bolts 36 having outwardly flaring heads at their lower ends counter-sunk in correspondingly shaped recesses in the arcuate members 25 and having nuts 31 on their upper ends. Although only one such tie bolt is shown in the accompanying drawings, it will be understood that an annular series is employed.

The cover casting 35 has its undersurface shaped to provide a plurality of bosses 38 and annular recesses 39, constituting upper end seats for compression springs 40, engaging upwardlv projecting bosses M on the concave backing 21. permitting limited upward tilting movement of the concave, under the influence of forces transmitted thereto by non-crushable objects, such as tramp iron, entering the crushing zone, as explained in the above identified application.

A cylindrical casing 45 for confining the material delivered to the crusher mav be supported upon the cover plate 35, and the springs 40 may be isolated from the material by a cylindrical guard 46, supported on the concave holder for vertical sliding movement with respect to the cover plate 35.

An upper spider 50, secured at its outer extremity to and carried by the cover casting 35, terminates centrally in a hub 5I having a keyed connection 52 with a bearing sleeve 53, hereinafter described, permitting relative vertical movement between the sleeve and the hub.

The inwardly projecting annular'member I'I associated with the lower frame section constitutes a support for the lower race of a thrust bearing assembly 60, arranged on a vertical axis and including a plurality of radiallv arranged roller bearings or the equivalent. The upper race of this assembly carried the outwardly projecting flange 6I of a cylindrical member or eccentric 62. The latter includes an upwardly projecting cylindrical body 63 journalled for rotation in the hub I5 coaxially with liner 60. with a stationary bearing sleeve or bushing 64 interposed between its outer surface and. the inner surface of the hub. A ring gear 65, fast on the flange 6| of the cylindrical member or eccentric is disposed in mesh with a driving pinion 66, carried by a drive shaft 61, journalled bearings carried by a lateral extension 68 of the lower housing I4 and receiving rotation from any suitable source of power.

The cylindrical interior of the eccentric body 53' is disposed on an axis eccentric with respect to the axis of bearing 60 and the outer surface of the body, and inclined with respect to the vertical, the axes of the interior and exterior surfaces of the eccentric intersection at the point of no motion Ill. The bottom surface II of the eccentric interior is normal to the axis thereof and terminates centrally in an aperture I2. The bottom surface constitutes a support for the lower race of a thrust bearing assembly 13, the upper race of which supports the lower end 14 of a shaft supporting sleeve I5. The latter includes an interior transverse wall I6 and an upwardly extending cylindrical side wall TI, having its inner and outer surfaces concentric to the inner surface of the eccentric and coaxial with the bearing assembly I3. A wear plate I8 ma be interposed between the bottom wall I6 of the sleeve I5 and the lower'end face of the gyratory shaft 80.

At its upper end, the stationary hub I5 carries an inwardly projecting, annular plate 85, having an upwardly extending, outer marginal rib 86 and a plurality of apertures 81 spaced equally therearound. The plate 85 extends inwardly over the upper end of the eccentric sleeve 63 and makes sliding contact with the upper end face 88 of the shaft supporting sleeve 11. Within the apertures 81 in the plate 85, there are a plurality of downwardly extending pipe sections 89, disposed in spacedrelation to the walls of vertical recesses 90 formed in the inner face of the hub I5, each recess being in communication through a vertical groove 9| with an annular groove 92 disposed substantially midway in the vertical height of the inner face of the hub I5. The annular groove 92 communicates with a passage 93 formed in the lower frame section I I, arranged to deliver oil to the lateral extension 68, for lubrication of the bearings for the shaft 61, as hereinafter explained.

The undersurface of the eccentric 62 carries a positive displacement pump. casing I00, having intermeshing gears IOI, I02 therein, the former being fast on a shaft I03 having a laterally projecting arm I04 secured to its lower end, in engagement with a post I05, projecting upwardly from the bottom of the lower housing section I6, to restrain the shaft I 03 and gear IOI against rotation with the pump housing I00, thereby to cause the gear I02 to planetate about the stationary gear and to deliver oil under pressure from the oil reservoir, defined by housing sections I4 and I6, to the interior of the eccentric, through the central opening I2 in the bottom thereof. It should be understood that the lower frame 'or casing I0, including housing sections I4 and I6, define an oil reservoir and that the oil normally stands at the level indicated by the broken line I06. The oil forced upwardly by the gear pump floods the bearing assembly 13, fills the hollow interior of the shaft sleeve 15, below the transverse wall I6, and is forced laterally through passage I01 formed therein. The eccentric side wall is provided with vertically extending flats or grooves I08, I09 in its inner and outer surfaces, constituting conduits for the flow of oil to the upper end of the eccentric, and to lubricate the surface contact between the inner face of the eccentric and the outer surface of the shaft supporting sleeve, and between the outer surface of the eccentric and the inner surface of the bushing 64, fixed to the inner face of the hub I5. Oil flowing upwardly through groove I08 to the upper end face of the eccentric is received in a plurality of grooves I I0 formed therein. As shown in Figure 3 these grooves are curved and inclined outwardly and rearwardly with respect to the direction of rotation of the eccentric, with the result that the oil is forced outwardly therein under the influence of centrifugal force, to return between the outer face of the eccentric and the inner face of the sleeve 64, the oil being confined by the upper plate 81.

1 Some. oil: escapes .inwardlylthrough. the sliding fit between the upper end face 88. of the shaft supporting sleeve 11 and the plate: 85, and substantially fills the space H I, betweenthe lower lend of the shaft 80 and sleeve 11. As the oil overflows tothe upper surface of plate 85, it will beconfined by themarginal rib 86 and willflow downwardly through the apertures 81 and pipes 98into passages 90 'andLBI, to the annular groove ill-and the lateral conduit 93, for delivery to the bearings for shaft 61. The pipes 89 prevent any oil, thrownoutwardly by centrifugal force by the eccentric "63, from. splashing'upwardly through aperturesIlI in plate 85.

- The eccentric sleeve 63 is provided with an aperture H2, establishing communication between vertical passages I98 and I09. Theaperture may be positioned near the upper ends of the vertical grooves or flats as suggested in Figurel or adjacent the pasage I01, as shown in Figure 2. In any event, there will be a preferential flow of oilupwardlythrough passage I08 and the space between the shaft supporting sleeve and the eccentric, and downwardly through the space between the eccentric and the bushing 64 and passage I09, as a result of the additional pressure applied to the oil by the centrifugally acting grooves III] in the upper end face of the eccentric.

In the oil reservoir within the lower casing sec tion I6, there is disposed a coil of tubing II5, having inlet and outlet fittings H6 and III, for the circulation through the coil of a cooling medium, such as water or the like. Such coils .havebeen used in the past, in an attempt to reduce the temperature of the oil in gyratory cr ushers', but their efficiency has not been what might be desired.

[A pipe. II3, disposed within the lateral passage 83, extends through the bushing sleeve 64 and. leads to a pressure gauge, to indicate the oil pressure in the system as a whole and more particularly, the pressure conditions between the sleeve and the outer surfaces of the eccentric.

The presentlinvention provides means for positively circulating the oil in the reservoir in heat exchange relation to the coil II5. Supported from theifloor of the lower housing section I6 is a fixed bafll'e means or conduit member, constitutinga centrifugal pump stator, and including anaXial-ly disposed cylindrical section H8, having a plurality of openings I I9 adjacent its lower end and. a laterally flaring, outwardly projecting upper portion I29. Above the latter portion, and arranged coaxially with the cylindrical portion H3 are a plurality of laterally projecting vanes IZI, curved rearwardly with respect to the direction of. rotation of the eccentric and secured at theirinnerends to the gear pump casing Hi0 for rotation therewith. These vanes constitute the impeller or rotor or a centrifugal pump, discharging laterally ln the space-between the outwardly flaring, laterally directed flange I20 of the stator and the bottom surface of the eccentric. The cylindrical'portion H8 of the stator constitutes the inlet, delivering oil axially and upwardly to the impeller, by inflow through the openings I19. Hence, the oil is positively circu- Iated at all times, downwardly and inwardly, over the. lower pipes of coil I I5, through openings ltd, upwardly to the impeller and outwardly past the upper pipes of the coil, forcefully into lubricating relation to the bearing assembly 60.

'.Th shaftd'b carries the usual crushing head I362, uponwhicha mantel I3I is. secured by a nut I32. The lower end of the head supports a sealing ring I33, making sliding engagement on a spherical surface with a ring I34 embracing the hub I5, thereby effectively preventing the admission of dust to the parts within the hub.

A floating crushing ring I35 may be interposed between the mantel I3I and the concave 28, as is understood in the art.

At its upper end, the shaft is surmounted by anupwardly and inwardly tapering bearing cap I40 disposed within the bearing sleeve 53, and having its upper end in spherical sliding contact with a sealing ring MI, carried by the bearing 5.3 and interposed between. the cap and a nut I42 having a complemental spherical undersurface. A gyratory fed plate I45. may be secured to the upper end face of the shaft, for controlling the delivery of material to the crusher, and may have vertically slidin connection with a weighted sealing ring I46 having a lower spherical surface making sliding contact with a complemental, upwardly facing surface on a sealing plate I41 carried by the central hub 5| of the spider. All of the above mentioned spherical surfacesare struck about the point of no motion 70, as a center.

In operation, the eccentric 62 is rotated by gears 66 and 65, thereby imparting gyratory movement to the lower end of the shaft, supported in the sleeve mounted on the thrust bearing I3, the upper end of the shaft beingsimply guided by the bearin 53 within the spider hub 5I. I

The rotation of the eccentric results in the oil circulation previously described. All parts are maintained lubricated and the oil is-kept cool.

Vertical adjustment of the crushing space between the mantel and concave may be eifectedby loosening the locking ring 22 and rotating the entire upper frame, thereby raising the concave. The. slidable, key connection between the spider hub andthe bearing 53 for the upper end of the shaft permits relative vertical movement of the spider with respect to the shaft, its upper bearings, and the crushing head, but prevents relative rotation between the bearings and the spider.

The invention is not limited to the details of construction shown in the accompanying drawings and described above, but covers all modifications comin within the appended claims and their equivalents.

I claim:

1. A crusher comprising a fixed lower frame, an upper frame secured thereto for relative vertical adjustment with respect thereto, a spider carried by the upper frame having a central opening, an. upper shaft bearing in the opening restrained against rotation with respect thereto, an annular thrust bearing supported in the lower frame on a vertical an upright cylindrical member journalled forrota-tion coaxially on and supported by said thrust bearing, said member having a cylindrical upwardly opening eccentric interior disposed in angular relation to its axis of rotation, and anti-friction thrust bearing in the bottom of and coaxial with the interior of said member, a cylindrical sleeve closely fitting said interior and supported on the bearing therein, a shaft having its lower end disposed within and supported exclusively by said sleeve and projecting upwardly therefrom on said angularly disposed axis, a crushing head carried by said shaft, an upwardly facing mantle thereon, and a downwardly facing, annular concave carried by the upper frame for vertical adjustment therewith,

the upper end of the shaft being disp'osedwithin said upper shaft bearing.

2. A crusher comprising a fixed lower frame, an upper frame secured thereto, a spider carried by the upper frame having a central opening, an upper shaft bearing in the openin restrained against rotation with respect thereto, an annular thrust bearing supported in the lower frame on a vertical axis, an upright cylindrical member journalled for rotation coaxially on and supported by said thrust bearing, said member having a cylindrical upwardly opening eccentric interior disposed in angular relation to its axis of rotation, an anti-friction thrust bearing in the bottom of and coaxial with the interior of said member, a cylindrical sleeve closely fitting the interior, supported on the bearing therein and having a transverse wall normal to its axis, a shaft having its lower end supported exclusively by said transverse wall and projecting upwardly therefrom on said angularly disposed axis, a crushing head carried by said shaft, an upwardly facing mantel thereon and a downwardly facing, annular concave carried by the upper frame, the upper end of the shaft being disposed within said upper shaft bearing.

3. A crusher comprising a fixed lower frame, an upper frame secured thereto for vertical adjustment with respect thereto, a spider carried by the upper frame having a central opening, an upper shaft bearing in the opening restrained against rotation with respect thereto but having vertically slidable connection therewith, an annular thrust bearing supported in the lower frame on a vertical axis, an upright cylindrical member journalled for rotation coaxially on and supported by said thrust bearing, said member having a cylindrical upwardly opening eccentric interior disposed in angular relation to its axis of rotation, an anti-friction thrust bearing in the bottom of and coaxial with the interior of said member, a cylindrical sleeve closely fitting the interior, supported on the bearing therein and having a transverse wall normal to its axis, a shaft having its lower end supported exclusively by said transverse wall and projecting upwardly therefrom on said angularly disposed axis, a crushing head carried by said shaft, an upwardly facing mantel thereon and a downwardly facing, annular concave carried by the upper frame, the upper end of the shaft being disposed within said upper shaft bearing.

4. A gyratory crusher comprising a fixed lower frame or casing defining an oil reservoir, an annular thrust bearing supported in said frame on a vertical axis, an upright cylindrical member journalled for rotation coaxially on said bearing, said member having a cylindrical, upwardly opening eccentric interior disposed in angular relation with respect to its axis of rotation, an anti-friction thrust bearing in the bottom of the interior of said member, a shaft having its entire weight supported by the last mentioned bearing and projecting upwardly therefrom on said angularly disposed axis, a lubricant pump carried by said member in said reservoir to deliver oil therefrom to the interior of the member for lubrication of said anti-friction thrust bearing, a plurality of outwardly projecting vanes supported below the eccentric for rotation about the axis thereof and deriving rotation therefrom to act as a centrifugal impeller, an upwardly extending centrifugal stator below said vanes cooperating therewith to circulate the oil in said reservoir, and oil cooling means in'the path of circulation of the oil.

5. A crusher comprising a lower frame or casing defining an oil reservoir in its lower portion and including an upwardly projecting cylindrical hub, an annular thrust bearing in said casing on a vertical axis, an upright cylindrical member journalled for rotation in said hub coaxially on said bearing, said member having a cylindrical, upwardly projectin eccentric interior surface having an axis disposed in angular relation to its axis of rotation, an anti-friction thrust bearing in the bottom of and coaxial with the interior surface of said member, a sleeve closely fitting said interior surface and supported by the bearing therein, a shaft having its lower end supported within and exclusively by said sleeve and projecting upwardly on said angularly disposed axis, a positive displacement pump carried by the bottom of said member, delivering oil from the reservoir forcefully to the interior of the member for lubrication of the anti-friction bearing, the sleeve, the eccentric and the hub surfaces and for return to the reservoir, a plurality of outwardly projecting vanes connected to and rotatable with the displacement pump and constituting a centrifugal impeller, fixed baffle means in the reservoir for circulating the oil under the influenceof -the impeller through a definite path, and oil cooling means in said path of circulation of the oil' 6. In a gyratory crusher, a lower casing or frame defining an oil reservoir, a rotatable eccentric journalled for rotation on a vertical axis in the frame, a plurality of outwardly projecting vanes mounted for rotation in the reservoir on the axis of the eccentric, constituting a centrifugal impeller and deriving rotation from the eccentric, bafile means associated with the impeller, having a downwardly extending, axially disposed cylindrical portion and an outwardly turned upper flange below the vanes, arranged to guide the oil through a definite circulatory path under the influence of force imparted thereto by the impeller, and oil cooling means in the path of circulation of the oil.

'7. In a gyratory crusher, a lower casing or frame defining an oil reservoir, an eccentric journalled for rotation on a vertical axis in the frame, a positive displacement pump housing in the reservoir suspended from the bottom of the eccentrio and rotatable therewith, a plurality of outwardly projecting vanes suspended from the bottom of the eccentric and rotatable therewith and constituting a centrifugal rotor, an upwardly extending centrifugal stator within said reservoir axially aligned with the rotor, defining an intake for delivering oil to the rotor and having a laterally turned portion defining a circumferential discharge conduit, and cooling coils in the path of circulation of oil discharged by said impeller.

8. In a gyratory crusher, a lower casing or frame defining an oil reservoir, an eccentric journalled for rotation on a vertical axis in the frame, a positive displacement pump housing in the reservoir suspended from the bottom of the eccentric and rotatable therewith, a plurality of outwardly projecting vanes carried by the pump housing and constituting a centrifugal rotor, an upwardly extending centrifugal stator within said reservoir axially aligned with the rotor, defining an intake for delivering oil to the rotor and having a laterally turned portion defining a circumferential discharge conduit, and cooling coils in the path of circulation of oil discharge by said impeller.

9. A gyratory crusher comprising a lower casing providing an oil reservoir and having an integral, cylindrical, upstanding hub shaped to provide oil return passages, an eccentric journalled for rotation in the hub, a shaft sleeve within the eccentric, a crusher shaft having its lower end disposed within the sleeve to receive gyratory motion from the eccentric, an annular plate se cured to the upper end of the hub, having an upstanding outer marginal rib and projecting inwardly in overlapping relation to the upper end of the eccentric and the sleeve, said plate having apertures aligned with the passages in the hub, and means for delivering oil under pressure upwardly adjacent the inner surface of the eccentric for overflow to the upper surface of said plate and for return through said apertures and return passages.

10. A gyratory crusher comprising a lower casing providing an oil reservoir and having an integral, cylindrical, upstanding hub shaped to provide oil return passages, a non-rotatable liner in the hub, an eccentric journalled for rotation in the liner and having a plurality of outwardly and rearwardly extending grooves in its upper end face, a shaft sleeve within the eccentric, a crusher shaft having its lower end disposed within the sleeve to receive gyratory motion from the eccentric, an annular plate secured to the upper end of the hub, having an upstanding outer marginal rib and projecting inwardly in overlapping relation to the upper end of the liner, the eccentric and the sleeve, said plate having apertures aligned with the passages in the hub, and means for delivering oil under pressure upwardly adjacent the inner surface of the eccentric for delivery un'der the influence of centrifugal force through said end grooves to the outer surface of the eccentric and for overflow to the upper surface of said plate and for return through said apertures and return passages.

11. A gyratory crusher comprising a lower frame or casing providing an oil reservoir and having an integral cylindrical upstanding hub shaped to provide oil return passages, a non-rotatable liner in the hub, an eccentric journ-alled for rotation in the liner, having a plurality of outwardly and rearwardly curved grooves on its upper end face and a vertically extending groove on its inner vertical face, a shaft sleeve within the eccentric, a gyratory crusher shaft having its lower end disposed within and supported by the sleeve to receive gyratory motion from the cocentric, an annular plate secured to the upper end of the hub, having an upstanding marginal rib, and projected inwardly in overlapping relation to the upper end of the liner, the eccentric and at least a portion of the upper end of the sleeve, said plate having apertures aligned with the pass-ages in the hub, and means for forcing oil under pressure upwardly through the groove in the inner vertical surface of the eccentric for delivery under the influence of centrifugal force through the grooves in the eccentric end 5 face to the liner and the outer vertical surface of the eccentric and for overflow into the interior of the sleeve and to the upper surface of the plate and for return to the reservoir through said apertures and hub passages.

12. A gyratory crusher comprising a lower frame or casing providing an oil reservoir and having an integral cylindrical upstanding hub shaped to provide oil return passages, a non-rotatable liner in the hub, an eccentric journalled for rotation in the liner, having a plurality of outwardly and rearwardly curved grooves on its upper end face and vertically extending grooves on its inner and outer vertical faces, a shaft sleeve within the eccentric, a gyratory crusher shaft having its lower end disposed Within and supported by the sleeve to receive gyratory motion from the eccentric, an annular plate secured to the upper end of the hub, having an upstanding marginal rib, and projected inwardly in overlapping relation to the upper end of the liner, the eccentric and at least a portion of the upper end of the sleeve, said plate having apertures aligned with the passages in the hub, and means for forcing oil under pressure upwardly through 2 1) the groove in the inner vertical surface of the eccentric for delivery under the influence of centrifugal force through the grooves in the eccentric end face to the liner and the outer vertical surface of the eccentric and for overflow into the L5 interior of the sleeve and to the upper surface of the plate and for return to the reservoir through said apertures and hub passages, said eccentric having a passage through its vertical side wall establishing communication between the 4 vertically extendin grooves therein.

SAMUEL WILLIAM TRAYLOR, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 313,818 Fraser Mar. 10, 1885 5-0 525,413 'Gates Sept. 4, 1894 525,443 Carman et al. Sept. 4, 1894 1,336,015 Bernhard Apr. 6, 1920 1,691,553 Rumpel Nov. 13, 1928 1,837,102 Bernhard Dec. 15, 1931 2,342,371 Roubal Feb. 22, 1944 2,291,122 Van Saun July 28, 1942 2,486,478 Kennedy Nov. 1, 1949 FOREIGN PATENTS Number Country Date 702,140 France Jan. 19, 1931 292,638 Italy Jan, 26, 1932

Images