US2422480A - Means for treating rubber - Google Patents

Description

June 17, 1941- w. A. GORDON I MEANS FOR TREATING RUBBER Filed June 29, 1945 4 Sheets-Sheet 1 Y June 17, 1947. w. A. GORDON MEANS FOR TREATING RUBBER Filed June 29. 1945 4 Sheets-Sheet 2 June 17, 1947. G'QRDON 2,422,480

MEANS FOR TREATING RUBBER Filed June 29, 1945 4 Sheets-Sheet 3 June 17, 1947. w. A. GORDON 2,422,480

MEANS FOR TREATING RUBBER Filed June 29, 1945 '4 Sheets-Sheet 4 Patented June 17, i947 MEANS FOR TREATING RUBBER William A. Gordon, Shelton, Coma, aulgnor to rmlng Company,' Incorporated,

Farrel-Bi Ansonia, Conn., a corporation of Connecticut Application June 29, 1945, Serial No. 622,245

ilaims. 1

This invention relates to means for treating rubber, and has particular reference to pelletizing machines of the general type disclosed in my Patent No. 2,288,405, of June 16,1942, and my Patent No. 2,370,952, of March 6, 1945.

In machines of this type the uncured plastic rubber is forced through peripheral perforations of a shell so as to emerge as strings or pencils, and these are cut oil by revolving knives and are sub- .lected to treatment while in the machine to overcome their tackiness, so that when discharged from the machine they will not stick together.

The .present invention is concerned particularly with provision for cuttlngoi! the strings or pencils, and provisions for treating the emerging strings and the pellets with a dusting powder to insure effective dusting before the pellets are discharged from the machine.

One object of the invention is to provide for very eflective treatment of the rubber with thedusting powder so that the pellets will be thoroughly covered.

Another object is to provide improved means whereby the dusting powder employed in the machine is supplied, distributed and conserved.

Another object is to improve in general and in detail the structure of machines of this type where the cutting mechanism and the dusting mechanism are embodied in the same machine.

In the accompanying drawings:

Fig. 1 is a side elevation, partly in v'ertical section and partly broken away, of a machine embodying the invention, the external powder supply receptacle being omitted.

Fig. 2 is an end elevation of the machine looking toward the left-handend of Fig. 1;

Fig. 3 is an enlarged section on line 3-3 of Fig. l; I

Fig. 4 is an enlarged section on line 4-4 of Fig. 1;

Fig. 5 is an enlarged section of a portion of the machine taken on line 5-! of Fig. 2;

Figs. 6 and 7 are sections on lines 8-! and 1-1, respectively, of Fig. 5;

Fig. 6A is an enlargement of a portion of Fig. 6;

Fig. 8 is a section on line I-Ioi' Fig. '1;

Fig. 9 is an elevation of the knife-carrying cage. the knives themselves being omitted;

Fig. 10 is an enlarged section on line iO-IO of Fig. 5:

Fig. 11 is an enlarged section on line il-ii of Fig. 6; and

Fig. 12 is a fragmentary view of certain parts shown in Fig. 11.

In its Beneral features the machine selected for illustration comprises a casing provided with a feed hopper into which the mass of rubber to be treated is introduced, said casing being provided with a long shaft or rotor driven atone end from suitable gearing, and having through a considerable portion of its length a feed screw which picks up rubber in the hopper and forces it through the casing longitudinally. The rubber is discharged laterally by the end portion of the feed screw through small perforations in the periphery of a cylindrical shell, so that the rubber emerges from the shell in the form of strings or pencils. the latter being cut off by a which, as the rubber issues from the perforations, cuts it into small pieces. These small pieces, during and after their formation and while they .are dropping from the shell, are treated in a confined space within a supplemental easing by subjecting them on all sides to the action of tackiness-destroying material such as talc or other powder sprayed into the supplemental casing so that, upon discharge from the supplemental casing, the pellets inhibit adhesion and maintain their individuality without sticking or locking together.

In this particular case the rubber supplied to the hopper has been rendered sufficiently plastic by suitable treatment, and the screw previously referred to is primarily a forcing screw for fore. ing the rubber mass out of the shell in the form of strings or pencils. This, however, is only by way of example.

In the drawings, the indicated generally at the large gear at one casing of the machine is it, the long shaft at H. end at it, the hopper or receiving chamber, which is intermediate the ends of the shaft, at it, and the feed screw at It. In the casing, shaft II has uitable bearings,

V such as shown at II and it, and at the discharge end of the machine for the end portion of is an outboard bearing l1 the shaft which is made in a separate piece, indicated at Il The outboard bearing "is provided upon a pedestal II. The cylindrical perforated shell through which the rubber is forced by the end portion of the feed screw is indicated at it, the same bein enclosed within a supplemental casing 20 within which is mounted a rotary cutting mechanism, generally indicated at II. The cutting mechanism ii is rotated from a suitable external prime mover such as an electric motor 22 mounted on top of the casing i0.

The dusting powder is sprayed into the supplemental casing from the left-hand end of the latter (Fig. 5) so that the pellets being produced revolving knife mechanism the main casing by l the ring member may, as

' ber 26 is fastened 7 rated shell is, and has and dropping from the perforated shell are thoroughly covered with the powder. The supplementaicasing 20 in this form ha an open lower end through which the completed pellets are discharged. v

The dusting powder to -bevused in-themachine is supplied from a suitable external receptacle 2!. which may which the powder passes to a suitable fan or blower. such as the rotary blower II, and from this blower the powder mixed with airis supplied under pressure to a ring-like chamber, generally-indicated at 2 from which it i elected of suitable nozzles into the ing the perforated shell I! and the frame memring member. The ring member 28 u n this no the open end portion of her maybe attached to shown, have a threaded socket 28 intowhich the right-hand end of shell I! (Fig. is screwed. The ring member "has an outstanding portion to which the frame memat a number of points by means such'as bolts 30. The framemember it is in the form of a shallow hollow housing extending above and below the main casing. It has parallel walls 28 and 28 of which the first is fastened to the ring member by the bolts ill, and the second of which serves as a support for the peripheral wall of the supplemental casing 20. The wall 28', moreover, is provided at its inner part with an opening in which rotates a portion of the knife cage, as hereinafter described.

The feeding screw is extends into the perfoits hollow body portion somewhat enlarged toward the left-hand end of the shell (Fig. 5), at the left-hand end of the body portion of the shaft or rotor. The separate shaft portion II is attached by means of bolts 3|, which bolts pass through a flange portion of shaft part II. This flange portion is surrounded by a bearing ring 82 fixed to the rotor, fitting closely against the inner surface of the perforated shell. To provide for possible leakage of rubber between the ring 32 and the inner surface of the perforated shell, the shell is provided with certain extra perforations at. the end, as will be noted from Fig. 5, these extra perforations being placed in a group beyond the regular perforations through shaft portion H has a portion ll which is received in the outboard bearing H. The bearing H has at the inner part a cap 33 formed on a spider 84 having a ring forated shell it by means such as bolts 36. In this manner the left-hand end (Fig. 5) of the perforated shell is effectivelysupported and centered. a

The cutting mechanism 2|, tioned, includes in its structure a cage, generally indicated at 40 (Fig. 9). This cage has suitable end members interconnected by connecting bars, and the right-hand and member (Fig. 9) has provisions whereby the cage can be driven from the motor 22. The left-hand and member is indicated at t! and the right-hand one previously mencasing 20, is alsomeans such as bolts 28, and

which the rubber is forced. The

35 attached to the per revolving knife aeaaeeo at 8|. These end members are interconnected by be a'vibratory receptacle from about in this parbars l1, shown as angle bars.

The end .member ll includes in its structure a plate ll attached to a The ring member 42 is adapted to rotate upon a bearing sleeve 44 embracing the ring member 21. and the plate H is adapted to rotate with a radially outward edge thereof in approximate contact with plate 28" and with a radially inward edge thereofin approximate contact with the shell ii. The member 42 above mentioned is provided at its outer periphery with teeth ll, thereby providing a sprocket engaged by a'chain 4U driven by a sprocket 41 on a shaft 48 driven from shaft 40 of motor 22 through a suitable coupling ill and a reduction gearing ll. The frame 26 rovides a housing in which a portion of one of the end members of the knife cage is disposed, and in which the driving provisions for the cage are disposed in part.

The left-hand end member 30 of the cage (Figs. 5 and 9) includes in its structure an annular member or collar 52 and a plate-like member 53. The annular member I2 is provided with a flange 84 to which the member II is attached by means 'suclnas bolts ll. The annular member I! has a smooth inner surface in contact with a solid portion of the perforated shell II, and at one side the annular member 82 is in contact with the ring it, previously mentioned, in a manner to holdthe knife cage in the proper longitudinal position with-respect to the perforated shell as the cage chamber, previously mentioned, which chamber. receives the dusting powder and supplies it to the interior of the supplemental casing. The

ring-shaped chamber 2! is preferably supported in a suitable manner from the structure supporting the rotary feed shaft, as by means of a supporting ring 51 interposed between the spider 84 and the inner part of chamber 25.

The chamber 25 varies in width at different points in its periphery, the same being of maximum width at the lower, part, where the same is joined to an inlet pipe 88 leading upwardly from the blower 24, and said chamber 25 being of minimum width at a point diametrically opposite the inlet. Within this chamber are a number of a nozzles that are adapted to receive the dust coming from the blower and elect it into the dusting chamber provided by the casing 20. These nozzles may be of a suitable number, and each may he of angular formation, having an inlet mouth at one end and at the opposite end an outlet directed at an angle to the inlet, the inlet branches being located within the chamber 25 and the outlet branches, on the other hand, being dlsposedexternally of said chamber.

In the form shown, there are nozzles, the same being indicated at 69. 'However, I do not limit myself to any particular number. In the form shown, there are two groups of nozzles, said groups being at opposite sides, respectively, of a diametrical line such as the section line 8-8 of Fig. 7, all of the inlet mouths of each group beingfaced toward the inlet pipe.

The inlet pipe supplies both groups, the arrangement preferably being substantially as shownin placed in front of the ring member 42 by bolts ll.

twelve of these of the nozzles of one group. The nozzles can be of simple form, as shown in'Fig. 10, and each can be readily fastened, as by welding, to the sheet metal wall It which constitutes oneof the walls of the chamber 25, the ejecting portion of each nozzle being within the main dusting chamber.

The nozzles preferably have their ejecting ends directed at. an angle to the axis of the perforated shell it, as shown in Fig. 5, so that the dust is ejected toward the strings or pencils as they issue from the perforated shell. In order to permit the nozzles to have full action in dusting the emerging strings, the plate member 53 of the knife cage is suitably open or cut away. It may be cut away in the manner shown in order to provide windows which, as the knife cage rotates, will pass the nozzles and permit the streams of dust to move directly through the plate 53, as well as over it. In the form shown, six windows 6| are provided in plate 53,-each window being comparatively wide compared to the outlet of one of the nozzles. Each nozzle will, therefore, direct powder through a window forv an interval as the knife cage rotates, and then a solid portion of the cage will be presented opposite said nozzle, and then another window will be presented opposite the nozzle, and so on. In the form shown, the windows 6| are placed so as to alternate with the connecting angle bars 31 of the knife cage, there being six of these bars. Alternate bars 31 act as supports for knives or cutting devices, generally indicated at 62, there being in this embodiment three of these cutting devices.

The alternate bars supporting the cutting devices 62 have flanges 31' arranged for support and adjustment of a knife structure, which is preferably constructed in the following manner: A knife 83, adapted to cut of! emerging rubber strings, is clamped in place in a knife holder comprising a body 64 and a cap 85. These parts are elongated and extend between the end members or heads of the knife cage, and the body 84 is mounted to swing on a longitudinal axis afford'ed by a longitudinal rod 68 fixed at its ends in the heads. The knife blade is clamped in place by a number of clamping screws 61 pass- 6 contact between the knife and the shell (note Fig. 6A) The rotation of the knife cage causes.

the edges of the knives to impinge against the sides of the strings of rubber. and the latter are cut oil in an effective manner. The plane of the knife blade may be at an angle of 50 or thereabouts with respect to the axis along which the string or pencil moves in issuing from the shell.

tended to provide a short depending vertical discharge throat presefiting a downwardly leading discharge of rectangular cross section, and

' this discharge throat is continued downwardly to some extent by the provision of a housing 16 having a discharge opening 16 registering with the throat 14. (See Fig. 5.) In horizontal cross section the housing or manifold 15 has the shape ing through the cap plate 85 and screwing into threaded sockets in the body 64. The flange 31?, previously mentioned, is provided adjacent its free edge with notches 68 in which are engaged the threaded shanks of headed bolts 89, of which the threads engage threads in sockets I0 in the side of the cap 66.

By screwing in the bolts 89, the knife holder can be swung so as to move the cutting edge of the knife in a direction away from the surface of the shell. Alternating with the bolts 68 is a series of bolts 'Il (Figs. 11 and 12) having threaded shanks screwing in and out in threaded sockets 12 of flange 31', and having ends abuttingthe side of the cap plate 65. The function of these bolts H is to swing the body'in a direction to move the knife edge toward the shell. After the knife has been adjusted to the desired position, it is firmly set in the fixed adjusted position by means of bolts I3 (one at each end of the knife i structure) which have threaded shanks enga ing threaded sockets in the flange 31 and have ends engaging the body 84 at points slightly oil'- set from the swinging axis of the body.

The knife is preferably held in a position in which the edge portion, which is beveled, has a very small clearance between it and the outer surface of the shell. it being unnecessary to have shown in Fig.4, the same having a body 11 extending lengthwise of the supplemental casing 20 at one side of the latter, and having branch portions .18 and Ill. The body 11 and the branches l8 and H! are hollow so as to provide a fork-shaped conduit-80. The body 11' has a flanged inlet 8| in communication with a conduit 82 which leads oil from the blower 24 at the suction side of the latter, whichis the righthand side as viewed in'Fig. l. The conduit 8.0 is, therefore, subjected to suction while the blower or fan is in operation, and the branch portions 18 and 19 are provided at their inner sides with elongated scireens 83 and 84. Through these screens the fine dust which has not been used in cpating the pellets is enabled to pass, but the pellets are screened out. By having this dust go back to the blower, it can be kept in circulation and can pass again into the dusting chamber to be applied to the pellets. As a substantial part of the dusting powder, which is in a free state, is caught before it enters the discharge, and returned into the machine, there is a very noticeable saving of powder. Also the air in the vicinity of the machine is much cleaner than it would be otherwise, which is an important point.

The external receptacle for the dusting powder is usually placed alongside the machine in the manner indicated in Fig. 2. In Fig. 1 this resuction conduit 82, so that said conduit takes fresh powder into circulation as needed.

It is believed thatthe operation of the machine in creating strings of rubber and in subdividing the strings will be apparent from the previous description. The knife cage can be rotated at any desirable speed in respect to the stationary perforated shell, so as to cut the strings into pellets. The pellets. as cut off at the exitsv of the perforations in the shell, drop off of the shell and move downwardly in the dusting chamber and are ejected by gravity from the opening at the lower end of the chamber. In the form shown, the lower open end of the discharge throat is spaced upwardly somewhat from the floor of the room, and a conveyor, not shown, may be used for carrying away the pellets as they drop out, but other provisions may be made for disposing of the dropping pellets as the conditions may require, the present showing being only by way of example.

The dusting powder being blown into the chamber from the left-hand end (Fig. in the manner above described, the same has full access to the pellets as they issue from the shell, and as they drop off from the shell during cutting and after being cut. The dusting streams move'toward and to the right-hand end of the cage (Fig.

5), and the dust moving into that region and not taken up by the pellets comes against the solid annular plate 4|, which may have suitable seal-' ing packing. not shown in detail, introduced between it and the adjacent fixed parts of the ma- .chine for the purpose of excluding powder, any

perforated shell is preferably cylindrical, it is of advantage to inject a considerable body of dusting powder into the dusting chamber at one end of the latter, in such a manner that a more or less uniform cloud or suspension of powder may have full access to the region where the strings are issuing and are being cut off. It is also of advantage to, haven plurality of streams coming in at the end of the chamber and directed at an angle to the shell so as to be inwardly converging, as previously described, and it is of advantage to have these streams supplied by nozzles, of which a plurality are used in connection with a distributing chamber, sai chamber being provided with a ring-like series of nozzles, as above described.

It will be seen that the present invention provides improved means for cutting off the strings by reason of the fact that it is, not required to maintain the knife edges in contact with the shell, and because, among other things, the knives can be very readily placed and held in the required operative positions. Three knives ,are shown in the present embodiment, but it will be understood that I do not limit myself to any particular number.

It will also be seen that the means for supplying is also improved to a notable degree.

It will be understood that while only one form of the improved machine is illustrated, the invention can take many diflerent forms, and various modifications in the procedure 'and in the organization of the machine parts may be made without departing from the principles of the invention or the scope of the claims.

What I claim is:

i. In a rubber-treating machine, a rotor portion. a surrounding cylindrical shell having a multiplicity of peripheral perforations, means on the rotor for forcing rubber out of said perforations, a casing enclosing the shell into which the emerging rubber enters and having a body portion substantially concentric with the rotor and also having a substantially radial and downward extension below the rotor forming a discharge throat, means external to the casing and at one end thereof for supplying powder into the casing in a plurality of streams converging toward the periphery of the shell, and revolving cutting. means in said casing for cutting 01! the rubber It is Of emerging from said perforations, a blowerfor supplying powder-containing air under pressure to said supply means, and means in association with said discharge throat for recovering free powder associated with the discharging pellets' and returning it to said blower.

2; In a rubber-treating machine, a rotor portion, a surrounding cylindrical shell having a multiplicity of peripheral perforations, means on the rotor for forcing rubber out of said perforations, a casing enclosing the shell into which the emerging rubber enters and having a body portion substantially concentric with the rotor and also having a substantially radial and downward extension below the rotor forming a discharge throat, means external to the casing and.

at one end thereof for supplying powder into the casing in a plurality of'streams converging toward the periphery of the shell, and revolving cuttingmeans in said casing for cutting off the rubber emerging from said perforations, a blower for supplying powder-containing air under pressure to said supply means,.and means-in association with said discharge throat for recovering free ing the pellets with a tackiness-destroying coatpowder associated with the discharging pellets and returning it to said blower, said last-named means including a suction manifold.

3. In a rubber-treating machine, a rotor 'por-" tion, a surrounding cylindrical shell having a multiplicity of peripheral perforations, means on therotor for forcing rubber out of said perforations, a casing enclosing the shellinto-which the emergingrubberenters and having a body portion substantially concentric with the rotor and also having a substantially radial and downward extension below the rotor forming a discharge throat, means external to the casing and at .one end thereof for supplying powder into thecasing in a plurality of streams converging toward the periphery of the shell, and revolving cutting means in said casing for cutting off the rubber emerging from said perforations, a blower for supplying powder-containing air under pressure to said supply means, and means in association with said discharge-throat for recovering free powder associated with the discharging pellets and returning it to said blower, said last-named means including a suction manifold, said manifold constituting a downward extension of said throat.

4. In a rubber-treating machine, a rotor portion, a surrounding shell having a multiplicity of perforations, means on the rotor for forcing rubber out of said perforations, rotary knife means disposed about the shell for cutting off the rub-. ber, a casing in which the cutting action takes place, said casing having-at the lower part a discharge throat, a plurality of nozzles for spraying dust-laden air into the casing. a blower for supplying dust-laden air to said nozzles under pressure, and a suction manifold and connections in association with the discharge throat for returning to the blower .free dust accompanying the discharging rubber pieces.

5. In a machine such as described, a cylindrical shell having a multiplicity of peripheral perforations, a rotor portion in the shell having means for forcing the rubber out of said perforations, a cage disposed about the shell and having end heads and bars interconnecting said heads.-

means to rotate 'said cage, a rod interconnecting said end heads adiacent one of said bars. a knife holder mounted on said bar and comprising a 1 a knife blade clamped bebody and a cap plate, tween the body and cap plate, and means between a 9 the said bar and the knife holder whereby the holder is rigidly clamped so as to hold the edge of the knife blade at a predetermined outward spacing from the external surface of the shell.

6. In a machine such as described, a cylindrical shell having a multiplicity of peripheral perforations, a. rotor'portion in the shell having means for forcing rubber out of said perforations, a cage surrounding the shell and rotatable about the same and including a longitudinal bar disposed outwardly of the shell and a longitudinal rod adjacent said bar, a knife structure including a knife blade, a holding body and a holding cap, said body being mounted'by means of said rod so that it can swing in and out relatively to the shell, and means in connection with the bar and knife holder whereby the knife blade is rigidly set in position with its edge at a predetermined outward spacing from the external surface of the shell.

7. In a machine such as described, a cylindrical shell having a multiplicity of peripheral perforations, a rotor portion in the shell having means for forcing rubber out of said perforations, a cage surrounding the shell and rotatable about the same and including a longitudinal bar disposed outwardly of the shell and a longitudinal r'od ad- 2,42a,4eo

7 members mounted in the bar adapted to swing Jacent said bar, a knife structure including a knife blade, a holding body and a holding cap, said body' being" mounted by means of said rod so that it can swing in and out relatively to the shell, and means in connection with the bar and knife holder whereby the knife blade is rigidly set in position with its edge at a predetermined outward spacing from the external surface of the shell, said last-named means including adjusting screw members mounted in the bar adapted to swing the knife holder outwardly, and other screw the knife holder inwardly.

WILLIAM A. GORDON.

REFERENCES CITED The following references. are of record in the file of thispatent:

' UNITED STATES PATEN'IS 1,829,831 Hiskey Nov. 3, 1931

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