US1397338A

US1397338A - Screen-separator

Info

Publication number: US1397338A
Application number: US388461A
Authority: US
Inventors: Thomas J Sturtevant
Original assignee: Sturtevant Mill Co
Current assignee: Sturtevant Mill Co
Priority date: 1920-06-12
Filing date: 1920-06-12
Publication date: 1921-11-15
Anticipated expiration: 1938-11-15

Description

T J. STURTEVANT.

SCREEN SEPARATOB.

APPLICATION FILED JUNE 12, 1920.

Patented Nov. 15 1921,

4 SHEETSSHEET I.

T. J. STURTEVANT.

SCREEN S EPARATOR. APPLICATION FILED JUNE 12, 1920' Patented NOV. 15, 11921. 4 SHEETSSHEET 2.

Jm m. m

T. J. STUHTEVANT.

SCREEN SEPARATOR.

APPLICATION FILED JUNE 12. 1920.

1 397 888 Patentefi Nov. 15, 1921,

4 SHEETSSHEET 3,

I11 vent o r:

T. J. STURTEVANT.

SCREEN SEPARATOR.

APPLICATION FILED JUNEIZ, 1920.

Patented Nov. 15, 11921:

4 SHEETSSHEET 4.

to the scalper and finer screen.

THOMAS J. EziTURTEVAIIT, 9F WELLESLEY, MASSACHUSETTS, ASSIGNOR T0 STURTE- VANCE MILL COMEANY, 0F BOSTON, MASSACHEFSET'I'S, A GORPORATIQN 0F MASSA- SCREEN-SEPABATOR.

Application filed June 12,

To all whom it may concern Be it known that I THOMAS J. STURTE- VANT, a citizen of the llnited States, residing at Welleslev, in the county of Norfolk and State of Massachusetts, have invented an Improvement in Screen-Separators, of which the following description, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts.

The invention to be hereinafter described relates to screen separators for grading materials.

It is desirable in separators of this type that the screen shall be vigorously vibrated to maintain the meshes of the screen clothing in open condition for efficient grading effect. ()ne of the purposes of the present invention, therefore, is to provide improved mechanism for vibrating the screen. In the present instance of the invention, this is accomplished by means of cams located beneath the screen, and serving to support the same. Preferably the arrangement of the cams is such that the screen is supported in distributed points, and the cams may be rotatedout of step so as to impart complex vibratory movements to the screen.

In some cases it is desirable to employ a coarse or scalper screen for initially grading the materials, and a finer screen beneath the same for further grading the materials. Another purpose of the present invention is to provide an arrangement of cams which may vibrate the fine screen, and through the latter vibrate the scalper screen.

It is desirable to be able to have ready access to the screens for the purpose of in spection, replacement or repair of parts thereof. Another purpose of the invention, therefore, is to provide a construction whereby convenient access may readily be had both In carrying this feature of the invention into effect, in the present instance. of the invention, the scalper screen is mounted on hangers depending from the cover of the separator casing, so that when the cover is lifted, the scalper screen will be lifted upward therewith away from the finer screen, thereby desirably exposing both of said screens.

Another purpose of the invention is to provide an arrangement of springs between the screens which may serve the dual function of transmitting vibratory movements Specification of Letters Patent.

Patented Nov. in, rear. 1920. Serial in. 388,461.

from the fine screen to the scalper screen, and yieldingly press the finer screen down toward the supporting camstherefor.

W1th the aforesaid and other purposes in view, the character of the invention mav be best understood by reference to the following descrlption of one good form thereof shown in the accompanying drawings. where1n:--

Figure 1 is a vertical longitudinal section through the separator shown herein as embodying the invention;

Fig. on an enlarged scale is a vertical longitudinal section through a portion of the separator shown in Fig. 1;

F g. 3 on an enlarged scale is a transverse sect on taken on line 3-3 of Fig. 1;

F igs. 3 and 3 are details to be referred to;

Fig. 4 011 an enlarged scale is a plan of the portion of the separator beneath the feed box with the cover removed, and a plan of a portion of 'an adjacent separator; V

F g. 5 IS a side elevation of the fine screen;

F g. 6 is a plan of the fine screen; and

Fig. 7 on an enlarged scale is an end elevation of a portion of the screen shown in Fig. 6.;

Referring to the drawings, the screen separator shown therein as one good form of the lnvention, may be provided with an suitablesupport, and preferably is inclosed by a casing, in the present instance, comprislng side walls 1, a front wall 3, an inclined rear wall 5 and a cover 7 provided with hinges 9 adjacent the upper end thereof,

' and a horizontal angle bar 11 at the lower edge thereof having a long flange 13 adapted to rest upon an inturned flange 15 of the front wall 3. The cover may be stiffened by transverse angle bars 17 disposed at suitable intervals. The bottom 19 of the casing may be open to deliver materials therefrom. Adjacent the front end of the casing, partitions 21 and 23 may be provided affording passages for conducting the tailings and finer materials graded from the casing. The upper end of the casing may be supported on suitable posts 25.

Suitable means may be provided for feeding the material to be graded into the casing described. To-accomplish this, in the present instance, a feed box 27 is mounted at the upper end of the casing, and contains a feed screw 29 adapted to feed the materials introduced at one end of the feed box along the same. \Vithin the feed box is a feed board 31 carried by adjusting screws supported on brackets 35 mounted at the ends of the feed box. Beneath the feed board 31 is a delivery plate 37 inclined downward toward the top of the casing. The construction is such that the materials fed along the feed box by the screw 29 will flow over the feed board 31 and gravitate downward onto the inclined plate 37 and be delivered thereby into the upper end of the casing.

The coarse or scalper screen, in the present instance of the invention, comprises screen clothing 39 having its mar ins riveted or otherwise secured to a frame, in the present instance, comprising side angle bars 41 connected by transverse end angle bars 43.

' To stiffen said frame and prevent the side bars 11 from flexing inward, tubular brace bars 15 may be provided preferably of arched form and having their ends flattened and secured to the side bars 11. These brace bars l5 may be connected to the screen clothing intermediate the side bars 41 by stirrups l7. l

The present invention contemplates that the scalper screen shall be supported by the hinged cover 7 of the casing. To accomplish this, in the present instance, hanger plates 49 may be secured to and depend from the cover into the casing a substantial distance. At the lower edges of these hangers plates are flanges 51 on which the side bars 41 of the scalper screen may rest. At the upper ends of the hanger plate flanges 51 are leaf spring stops 53 having portions normally standing up somewhat from said flanges. To hold the scalper screen down on the flanges 51, limiting lugs 55 may be provided secured to the hanger plates at points somewhat above the flanges 51. The construction is such that when the cover 15 opened, the scalper screen may be slid inward between the hanger flanges 51 and the lugs 55, and in the course of this movement, the depending flange of the upper transverse angle bar 43 of the scalper screen will ride over the stop springs 53. Thereupon, the latter will spring upward and engage said transverse bar so as to prevent the scalper screen from sliding down along the hanger plates.

The finer screen, in the present instance of the invention, comprises screen clothing 57 having its margins tacked or otherwise secured to wooden side bars 59, and further secured by wooden bars 61 connected by screws or other suitable means to the bars 59. The wooden side bars 59 may be adjustably connected by bolts 63 with side angle bars 65.

having the ends thereof connected to transverse angle bars 67. \Vooden bars 69 may be mounted on these end angle bars and be secured thereto by bolts 71. The side angle bars 65 are preferably connected by a pair of channel bars 73 riveted or otherwise secured to the side angle bars, and these channel bars serve to support the side angle bars 65 and the screen carried thereby as will be described. An angle :bar 75 rivetedor otherwise secured to the angle bars 65 and located upward a substantial distance above the' wooden side bars 59 so as to prevent the ma terials passing through the scalper screen onto the upper surface of the finer screen from escapingover the edges of the latter.

The present invention contemplates that the screens may be supported on and vibrated by cams -located beneath the finer screen.

In the present instance of the invention,

four cams 79 are provided, each having six projections 81. These cams may be desirably constructed of sections which may be secured together by bolts 83, and may be mounted fast on horizontal shafts 85, a pair of cams being provided on each of said shafts. The ends of the shafts may project outward through elongated openings 87 in the side Walls of the casingfand may be journaled in bearings 89 in brackets 91 secured by bolts 93 to the side walls of the casing and to channels 95 riveted to the side walls of the casing. Preferably the bearings 89 are located eccentrically with respect to the brackets 91, so that they may be reversed and vary the elevation of the shafts 85, and vary the distance of the finer screen from the scalper screen as desired. The elongated openings 87 in the side walls of the casing andin the channels 95 enable ready reversal of the bearing brackets 91, the construction of the brackets being such that they close the portions of the elongated openings 87 not occupied by the shafts in either position of the brackets, and thereby prevent escape of materials from the casing through said openings.

The shafts may be rotated by sprocket wheels 97 fast on ends thereof projecting beyond the bearings at one side of the casing, said sprocket wheels being connected by a sprocket chain 99. A pulley 101 may be mounted on the upper shaft and be driven by a belt from any suitable source of power.

Above the cams are rollers 103 having to transmit vibratory movements from the cams to the channel bars, and the vibrations will be transmitted therefrom tothe side bars of the screen frame and efficiently vibrate the screen clothing mounted thereon. The rollers 103 are preferably secured to the channels 7 3 in such a position that the channels serve to house the rollers more or less, as shown, to protect them from the falling materials.

The screens are mounted in inclined position in the casing, and therefore, it is desirable to provide means to hold the fine screen frame inposition such that the rollers 103 will be properly mounted on the cams 81. To accomplish this, in the present instance, a pair of hanger rods 109 are provided having their upper ends provided with eyes 111 mounted on pins 113 carried by brackets 115 secured to the upper end of the casing. Coil springs 117 encircle the lower ends of the hanger rods 109, and are confined between washers 119 engaging nuts 121 threaded on said hanger rods. Intermediate the ends of the coil springs 117 and encircling the hanger rods are a pair of washers 123 adapted to engage opposite sides of the upper flange 125 ofthe upper channel bar 73 of the fine screen frame. The construction is such that on rotation of the cams in a clockwise direction, the fine screen may be given a reciprocatory movement longitudinally as the rollers 103 ride over the cam projections 81.

As stated, the present invention contemplates that the vibratory movements imparted to the fine screen by the cams shall be transmitted therethrough to the scalper screen. To accomplish this, in the present instance of the invention, coil springs 127 are provided intermediate said screens and have their lower ends mounted in sockets 129 secured to a longitudinal bar 131 of wood or other suitable material located intermediate the side bars of the fine screen frame and secured to the end angle bars 67, the channel 73 and the angle bar 75. The upper end of these coil springs 127 may engage plates 135 secured to the scalper screen clothing 39. The construction is such that these coil springs 133 serve to impart Vibratory movements from the finer screen to the scalper screen, and the same cams which serve to vibrate the Ifiner screen will als serve to vibrate the scalper screen.

In some instances it may be desirable to assemble side by side a plurality of separator units such as described, and to have cam shafts common to all of the separator units.

To enable proper spacing of the casings of the separator limits, the bearings at one side of the casin {may be mounted on the inside thereof, an spacer members 145' may be provided adapted to be interposed between and engage the side walls of the adjacent walls of the separator units. Bolts of sulficient length may be provided to extend through the bearing brackets 91 and the spacing member 145.

In operation, the materials to be graded are delivered as described from the feed box down into the upper end of the casing. The materials will flow downward along the 'upper surface of the scalper screen, the coarser materials being discharged over the lower .end thereof, while other materials will pass throughthe screen clothing, and fiow down-' ward along the fine screen. The coarser of these materials will be delivered over the lower end of the fine screen, while the finer materials will pass therethrough and be .delivered through the opening 19 at the bottom of the casing. The cams 81 rotated as described, will impart complex vibratory movements to the fine screen including up and down vibratory movements as well. as

movement longitudinally of the screen. These vibratory movements will be transmitted in turn by the springs 127 and the bar 131 to thescalper screen.

The cams supporting the lower screen produce a highly desirable shaking or vibration effect which maintains the meshes of the clothin in open condition even when materials o sticky character are graded. Since the frame of the lower screen is unconfined,

the projections of the cams on rotation thereof willproduce successive bumps which will knock the screen as a whole bodily upward. The disposition of the cams and the timing of the engagement of their projections with the screen are such that the screen may be given a'composite longitudinal and lateral rocking motion which will toss and turn over the materials so that the materials may readily reach the screen to be graded. Hence this prevents formation of layers or strata of materials and flow of the upper layer along the lower layer without coming in contact with the screen clothing so as to be graded thereby. Not only is the screen vigorously shaken as a whole,- but also the clothing receives a consequent vibration relatively to the screen frame, thereby desirably cooperating with the bodily vibration to pro duce eflicient grading effect.

These vigorous vibratory movements of the lower screen are in turn transmitted to the upper screen through the coil springs which are confined between the screens. The springs react from the upper screen so as to press the lower screen down against the supporting cams therefor. As a conse quence the rollers carried by the fine screen are snapped down into the hollows between the projections of the cams, which further contributes to the vigorous vibration of the screens.

If it is desired to have access to the screens for the purpose of inspection, replacement or repair thereof, it is merely necessary to swing the cover to open position, thereby l and having carrying with it the coarser screen mounted plates 135 will return to the coil springs without requiring attention on the part of the operator.

By my invention, a simple, strong and efficient separatoryis provided, and the screens are given powerful vibratory movements which will maintain the meshes of the clothing thereof [in open condition f/or eflicient grading effect.

It will be understood that the invention is not limited to the specific embodiment shown, and that various deviations may be made therefrom without departing from the spirit and scope of the appended claims.

What is claimed is:-

1. A separator for grading materials, comprising, in combination, a casing, a frame therein, screen clothing connected to said frame, channel bars extending transversely of said frame and having depending flanges, rollers secured to the channel bars in the space between the depending flanges for protection from the falling materials, cams supporting said rollers, and shafts for rotating said cams, thereby to vibrate said frame and clothing.

2. A separator for grading materials, comprising in combination, a lower screen comprising a frame having screen clothing connected thereto, an upper screen supported independently of the lower screen screen clothing connected thereto, cams adapted to floatingly support and vibrate the lower frame, and means located at distributed points between the clothings of the two screens to transmit vibrations from the lower frame to the upper clothing.

3. A separator for grading materials, comprising, in combination, upper and lower screens, cams for sustaining and vibrating the lower screen, and spring means to transmit vibrations from the lower screen to the upper screen.

4. A separator for grading materials, comprising, in combination, upper and lower screens each comprising a frame having screen clothing connected thereto, means for supporting the upper screen independently of the lower screen, cams for supporting and vibrating the lower frame, and means to transmit vibrations from the lower frame to the upper screen clothing.

5. A separator for grading materials, comprising, in combination, upper and lower screens, a support for the upper screen, cams for supporting and vibrating the lower screen, means for llmitlng longitudmal movements of the lower screen, and

springs for transmitting vibrations from the lower to the upper screen.

6. A separator for grading materials, comprising, in combination, a casing having a hinged cover, hangers depending from said cover, an upper screen mounted on said hangers, and movable with the jeover, a

lower screen beneath the upper screen, cams for supporting and vibrating the lower screen, and means to transmit vibrations from the lower to the upper screen, said cover and upper screen being movable up from the lower screen to render said screens readily accessible.

7. A separator for grading materials, comprising, in combination, a casing having a cover, upper and lower inclined screens therein, means to support the upper screen from the cover, shafts journaled in bearings mounted on'the casing, cams on saidshafts supporting and vibrating the lower screen, means to limit longitudinal movement of said screens relatively to said cams, and means to transmit vibrations from the lower to the upper screen.

8. A separator for ading materials, comprising, in combination, a casing having a cover, upper and lower inclined screens therein, means to support the upper screen from the cover, shafts, cams on said shafts for supporting and vibrating the lower screen, hanger means connected to the cas' ing and the lower screen to limit longitudinal movement of the lower screen relatively to said cams, and means to transmit vibrations from the lower to the upper screen.

9. A separator for grading materials, comprising in combination, a support, an upper inclined screen, a lower inclined screen comprising a frame having screen clothing connected thereto, cams mounted on said support for sustaining and vibrg; ing the lower frame and clothing, hanger means connected to the lower screen and support to limit longitudinal movement of the lower screen on the cams, and means to transmit vibrations from the lower to the upper screen.

10. A separator for grading materials, comprising, in combination, a casing, a pair of shafts journaled in bearings thereon, a pair of cams on each of said shafts, a lower screen resting on and supported by said cams and vibrated on rotation of said cams, and an upper screen above and supported independently of the lower screen, and means for transmitting vibrations from the lower to the upper screen.

11. A separator for grading materials comprising, in combination, a. casing having a cover, hangers depending from said cover, an upper screen mounted on said hangers, means on the hangers to limit upward movement of said screen thereon, a

eer/nee for supporting and vibrating the lower screen, and spring means confined between said screens for pressing the lower screen toward said cams.

12. A separator for grading materials, comprising in combination, a casing, upper and lower screens mounted therein, cams for supporting and vibrating the lower screen, and brackets having bearings eccentrically disposed thereon, said brackets being reversible to vary the distance of the lower from the upper screen.

15. A separator unit comprising a casing having side walls, a screen therein, cams vibrating said screen, a shaft for said cams, bearings for said shaft mounted on the side walls of the casing, and a spacing member adapted to be interposed between a side wall of said unit and a side wall of a. similar separator unit positioned to one side of the first unit to space said units.

14:. A separator for grading materials, comprising, in combination, a' screen comprising a frame having channels extending across the frame and provided with depending flanges, and screen clothing on said frame; cam engaging means secured to the channels between each end and the center thereofand in the space between the depending flanges for protection from the falling materials, a supporting cam beneath each of said cam means and in position to engage the same and to floatingly support the frame, and means to operate the cams to vibrate the frame and screen clothing.

15. A separator for grading materials, comprising, in combination, a casing havmg a cover, an upper screen carried by the cover and movable therewith, screen supporting cams carried by the casing, a lower screen floatingly supported beneath the upper screen by said cams and vibrated by the cams, and means to transmit vibrations from the lower to the upper screen.

16. In a separator for grading materials, in combination, an upper screen, a lower screen comprising a screen frame having spaced longitudinally extending side bars and transversely extending channel bars secured to the side bars at points substantial distances from the ends of the latter to hold the side bars in spaced relation, means for supporting screen clothing from the side bars, means below said channel bars to support them and operable to vibrate the frame and screen clothing carried thereby, and means to transmit vibrations from the lower to the upper screen.

17. In a separator for grading materials, in combination,- an upper screen, a lower screen comprising a screen frame having spaced longitudinally extending side bars and transversely extending channel bars secured to the side bars at points substantial distances from the ends of the latter to hold the side bars in spaced relation, cam means below said channel bars to support them and fioat'ingly support the screen frame, means to operate the cam means to vibrate the frame and screen clothing carried thereby, and means to transmit vibrations from the lower to the upper screen.

lln testimony whereof, I have signed my name to this specification.

THOMAS J. STURTEVANT.