US1798026A - Agitating and conveying apparatus - Google Patents

Description

March 24, 1931. M. MCGUINNESS 1,798,026

AGITATING AND CONVEYING APPARATUS Filed Jan. 29, 1929 3 Sheets-Sheet 5 lily/1111111111 ATTORNEXS M. M GUINNESS 1,798,026

AGITATING AND CONVEYING APPARATUS Filed Jan. 29, 1929 3 Sheets-Sheet 1 March 24, 1931.

E I/pu/nnc s 5 ATTURNE 70' Patented Mar. 24, 1931 UNITED TATES MAXWELL MCGUINNESS, OF LONDON, ENGLAND AGITA'IING AND CONVEYING APPARATUS Application filed January 29, 1929, Serial No. 335,887, and in Great Britain February 11, 1928.

This invention relates to the treating of materials particularly by mechanical agitation during conveyance with or without simultaneous chemical or physical treatment such as by heat. The apparatus embodying the present invention is particularly applicable to the treatment of materials that become tacky or plastic when heated such for example as shale coal petroleum refining residues and similar carbonaceous material as used in the manufacture of smokeless fuel by low temperature carbonization and for the driving off of hydrocarbon vapours therefrom, but it is not exclusively and solely applicable to the low temperature carbonization of coal as the apparatus is equally applicable to the mixing or agitation and simultaneous conveyance of tacky or pasty or solid materials generally as hereinafter mentioned.

Various substances that are solid under normal conditions become so tacky or viscous while undergoing heat treatment and adhere so firmly to the apparatus employed in treating them and set so hard on cooling that the apparatus soon becomes so coated, clogged and otherwise obstructed as to be rendered unworkable. The chief object of the present invention is to provide apparatus for enabling substances of the kind above stated to undergo heat treatment without rendering the apparatus inoperative. p,

The inventionis however applicable to the agitation and simultaneous conveyance of materials for thoroughly mixing two or more components or drying or cooling or simultaneous heating and drying or, heating and cooling various substances such for example as wood pulp.

lVith the above object in view and such others as are incidental thereto or hereinafter appear the invention in its broad aspect may be regarded as consisting in a chamber or casing and impellers therein which while impelling the material through the chamber are continually cleaning one another.

By regulating the feed of the material into the chamber in which it undergoes the treatment and by continually moving it onwards through the chamber an accumulation of an unwieldy mass is avoided, and by so shaping and spacing the impellers that they are continually scraping or cleaning one another and the wallsof the chamber, no firm adherence of thematerial either in pasty or solid form to the said impellers or chamber walls can take place.

In one simple form of the apparatus the impellers operate paddle-wise their paths of movement being overlapping circles and their distance apart being such that the'tip of each impeller sweeps over the surface of a correspondingly shaped portion of an adjacent impeller during part of its travel. The chamber is preferably so formed that each impeller sweeps closely over a portion or portions of its wall during other portions of its travel.

The impellers may be arranged on a row of parallel shafts extending transversely across the chamber, into one end of which. the material is fed from a chute and feed regulator.

According to one constructional form of the impellers each of them is rectangular in face view and multiple concave in end view or cross section. Each impeller may for example have two, three or four concave faces and be correspondingly rotated in two, three or four stages of angular movement per revolution and become temporarily locked in position after each stage of movement while the other impeller or impellers turn through one stage. I

driving and locking mechanism for the impellers.

Figure 4 is a group of diagrams (a) to (e) illustrating the principle of operation of the apparatus.

Figure 5 is a longitudinal sectional elevation showing somewhat diagrammatically a modified form of apparatus.

Fi ure 6 is a fragmentary sectional elevation of the delivery end of the apparatus and means for removing the treated material therefrom.

Figure 7 is a fragmentary sectional elevation of special means for maintaining a gas passage along the upper part of the apparatus.

Figure 8 is a diagrammatic view of a further embodiment of the apparatus.

Figures 9 and 10 are diagrammatic views in plan and elevation of a further embodiment.

Referring first to the apparatus shown by way of example in Figures 1 to '5 it is to be observed that the apparatus comprises four impellers A, B, C, D, arranged side by side on parallel horizontal shafts projecting from ieir assembled casings which constltute the continuous chamber 1 in which the impellers turn. Each impeller is in the form of a drum having four concave faces and the impeller shafts are so spaced that the impeller paths overlap as shown. Impellers A and L are turned through a quarter revolution while B and D-are locked stationary and then B and D turn in the same direction while A and G are locked stationary and so on. The tip of each moving impeller sweeps out the concavity presentedby the adjacent face of the adjacent stationary impeller.

The material to be treated enters past a regulator-2 in-a chute or hopper 3. In Figure 1 it passes along the top spaces of the impellers to the end one and thence down and along the bottom spaces to the outlet 4: (Figure 1-). In Figure 5 on the other hand the material enters at one end of the chamber and passes out at the other end.

The operation of both types of apparatus above described will be readily understood by a consideration of Figure 4 in relation to Figure 5.

InFigure a stage (a) it is assumed that impellers A and C have performed 4 quarterrevolutions and that B and D are in the act of performing their fourth quarter-revolu- As will tion while A. and C are stationar be seen and readily understood unpeller B ing Figure 4 it will be seen that each impeller scrapes material from the preceding one and eventually presents it to the succeeding one. The material is thus conveyed along by impellers which constantly clean each other and also clean the walls of the chamber.

Any gases that may be evolved or any gases that maybe introduced as a gaseous medium can escape through the gas passage 5.

If the material after treatment is not too sticky it will fall from the last impeller through the outlet 4 (Figure 5) and may be received into a tank 6 or one or other of two alternative tanks of water or other liquid Which acts also as a gas-seal. If thematerial is liable to stick to the last impellermeans may be provided to positively remove the same. An example of such means is shown in Figure 6,-in which 7 represents a plate which is reciprocated by any convenient means (such as a cam slot not shown) to move inwards and recede at the correct rate to preserve in turn against each face of the impeller A a wall which diverts the plastic mass into a delivery conduit 8 along-which it is forced and may be treated as it escapes so as to assume any desiredform such as briquettes.

Although-in the preferred constructional form above described, the floor and roof of the chamber are composed of arcuate portions corresponding to the sweep of the impeller tips the roof need not be so shaped'but may be fiat .or arched to provide a clear space above the impellers paths, nor indeed need the floor be thus shaped particularly in the case of treating material that is orbecomes semi-plastic because even if the floor he uniformly fiatsuch material will collect to some extent and be shapedby the sweep of the impellers to assume a multiple arcuate formation as shown in Figure 5. The arcuateshaped roof for-the multiple-impeller chamher is preferable in some respects but it does not present an easy path of travel for evolved gases, and I may-therefore resort to the construction'shown incFigure 7 to ensure thispath. This consists in forminggaps or slots 9'on the end edges of the impellers near their tips and providing sta-tlonary lugs or studs 10 orthe like onthe chamber end walls which registerwith the slots as the slotted portions 'of the impellers sweep past them. In this way the saidslots or gaps which would n o1 mally'become cloggedbythe solid material 5 un dertreatment are automatically de-clogged by the lugs or studs. The most convenient position for the dc-clogging lugs or studs is symmetricallyin the space thatis common to adjacent impellers as shown in Figure 7 so T thatthey first serve to clearthe slots on one impellerand become themselves loaded by the clogging mass and then themselves become cleared by the slots of the adjacent impeller.

It will'be understood that the-lugs or studs project inwardly from the end walls of the enclosing chamber, each lug or stud being substantially diamond shaped in end view but with arcuate edges instead of straight edges.

The impellers are not necessarily arranged as a single row on parallel horizontal axes as in Fi ures 1 and 5 but may be nested as for "example by being arranged in a plurality of rows with intervening interconnecting impellers as for example in-zig zag form as shown in Figure 8.

The impeller shafts are not necessarily horizontal and may in fact be vertical as will be understood by regarding Figures 4 and 8 for example as being plan views instead of elevations; in this case gravity will prevent the material from rising to to the roof and a free space for gases will naturally be preserved over the top ends of the impellers, as shown in Figure 10.

In Figures 9 and 10 the impellers shown have three arcuate faces in place of four, this construction being preferable with some materials as the cavities are deeper and the scraping edges have a greater scooping effect and a less squeezing effect on the material than is the case with shallow cavities.

The intermittent movements of the impellers may be efiected by any appropriate means such for example as ratchet and pawl or rack and pinion mechanism the odd numbered impellers (A and C) being moved together while the even numbered impellers (B and D) are locked and vice versa, and the driving of these two groups of impellers being alternating for the successive stages of movement. Driving mechanism of this kind is shown in Figure 3 where a driving shaft 11 operates through gears to drive a rotary cam disc 12 which actuates a roller 12 common to two lever mechanisms adapted to rock locking pawls 13 and 14 against the counterforce of springs 13 and 1st into and out of engagement with quadrantally notched discs 15 and 18 on countershafts 17 and 18, while eccentrics 19 and are operated from the same driving shaft to swing ratchet pawls 21 and 22 repeatedly through small angular feed movements, and thereby turn ratchet wheels on the shafts 17 and 18 and hence also the shafts themselves angular distances cumulatively amounting to quarter revolutions between each locking stage, shaft 17 being locked while 18 is turned and vice versa. The shafts 17 and 18 are geared at 17, 18 to the shafts of the impellers A O and B D respectively. As shown the locking pawls 13 and 14 are integral with rocking levers 18 and 14 respectively formed with curved tracks 13 and 14 adapted to engage rollers 21 and 22* on the tails of the pawls 21 and 22 which are pivotally carried on arms 21 and 22 on the shafts 17 and 18 respectively.

The connecting rods 19 and 20 respectively between the eccentrics 19 and 20 and effect in the event of the impellers becoming ammed 111 their cylinders by obstructive material and thereby preventing the ratchet 'pawls 21 and 22 from turning the shafts 17 and 18.

The conditions to be observed in utilizing the apparatus will naturally difier for different substances. In the case for example of requiring to merely heat or dry or both heat and dry a damp or pasty or sticky mass the apparatus may be heated to a uniform temperature or to temperature progressively increasing along its length and the heat may be applied externally as for example by gas jets as shown at 1 in Figure 5 or for example by hot air or steam or other gases. If the mass enters the apparatus in a hot condition and requires to be cooled, the apparatus may be kept cool in any desired manner as for example by a cold water jacket r by circulation of cold air or gases inside the apparatus. In either of the above cases the impellers themselves may if desired be made hollow to accommodate a heating or cooling medium.

In the case of requiring to subject a material to some treatment regardless of temperature as for example the exposure of a mass to the action of a gaseous chemical reagent, the provision of heating or cooling means may be dispensed with.

In the case of mixingtwo or more substances with or without the application of heat, particularly the mixing of materials that become tacky or pasty during the mixing operation, provision may be made for the introduction of the component materials at any suitable point or points along the apparatus.

In the case 'ofheating material to evolve gases or vapours therefrom I may utilize the evolved gases or vapours after superheating the same as the heating medium. For this purpose a fan may be employed to force the superheated gases or vapours throughthe interior of the chamber. To assist in the heating of the chamber the evolved gases or vapours after issuing therefrom may be conducted under or around the chamber before passing to condensers or'the like for subsequent treatment. The length of the chamber and the speed of travel of the material through it are such that practically all or as much of the gases and vapours as may be desired are extracted.

The impellers may be made of metal or concrete or other suitable material and their scraping tips may be metal-shod or otherwise I renewable. Similarly the chamber may be of firebrick or other non-metallic material or it may be of metal and provided with liners.

The apparatus may be adapted for treatme t als unde pre su v--e" ate than atmospher c or-u nd er reducedpressure providing overlapping paths of rotary movement, and means for imparting-a partial r0 tation tooddnumbered drums While the even numbered are stationary and vice versa.

2. Agitating and conveying apparatus comprising a chamber 'a plurality of concave-faceddrums of polygonalcross section mounted rotatably within the chamber with their axes parallel and at a distance apart such that each drum during a partial rotaiion sweeps into the concavity ofthe adjacent faceof an adjacent drum, and means for imparting a partial rotation to odd numbered drums while the even numbered are stationary and vice versa.

3. Agitating and conveying apparatus comprising a chamber, a plurality of concave-faced impeller drums of polygonal cross section mounted rotatably within the chamber with their axes parallel and so shaped and spaced that each drum during rotation sweepsinto the concavity of the adjacent face of a preceding drum thereby scooping out material in the cavity and thereafter by furth r rotationpresents it for being scooped by a succeeding drum, andmeans for rotating odd numbered drums while the even numbered are stationary and vice versa.

4. Agitating and conveying apparatus comprising a chamber, a plurality of concave-faced impeller drums of polygonal cross section rotatably mounted within the chamber with their axes parallel and so shaped and spacedthat, eachdrum during rotation scoops materialundertreatment from a preceding drum and presents it i'orbeing scooped by a succeeding drum, means for rotating odd numbered drums while'the even numbered are stationary. and viceversa, and means forlocking each'drum while the material on one face thereof is being removed by a succeeding drum. 7

5. Agitating and conveying apparatus comprising a chamber, a-pluralityoi concave-faced impeller drums of polygonal cross section rotatably mounted within the cnamber with their axes parallel and so shaped and spaced that each drum during rotation sweeps into the concavity of the ad jacent face of an adjacent drum, meansfor rotating odd numbered drums ,whilethe even numbered are stationary and vice versa,,and means for heating the material as itisbeing impelled 6. Agitating and conveying apparatus se p i g: am w th mult p e n e d arched floor, a plurality of concave-faced drums of polygonal cross section mounted ,rotatably withinthechamber with their axes parallel and-at a distance apart providing overlapping paths of movement each corresponding with an arch of the floor and means 01 imparting a partial rotation toodd nunr bered drums while the even numbered are stationary and vice versa.

7 Agitating and conveying apparatus comprising a chamber-With multiple arched roof and multiple inverted arched floor, and a plurality of concave-faced impeller drums of polygonal cross sectionmountedrotatably within the chamber with their axes parallel and soshaped and spacedthat each drumdur ing rotation sweeps closely over correspgnding-arched roof anclfloor portions-and into the concavity of the adjacentiface ot-apre? ceding drum thereby scoopingout material in the cavity and thereafter bywfurther rotation presentsit for being scoopedby asiics ceeding drum, and means-for rotatingodd numbered drums while theeven numbered are tionaryand vice-versa.

8. Agitating and conveying apparatus comprising a chamber ithmultiple arched roof and multiple inverted arched floora plurality of concave-faced impeller drumsof polygonal cross section mounted'r tatabl-y within the chamber withtheiraxes parallel and so'shaped and spaced that each drum during rotation sweeps closely over COIIe spending arched roof and floor portions and into the concavity of thead 'acent face of a preceding drum therebyscooping out material in the cavity and thereafter-by fur-then rotation presents it for being scopedby asucceeding drum; means for rotating odd numbered drums while the even numberedare stationary and vice versa, and means for locking eachdrum whilethe material on one face thereof is being removed by a succeeding drum. I

9. Agitating and conveying apparatus comprising a chamber Withmultiplearched roof and multiple inverted arched floor, a plurality of concave-faced impeller drums of polygonal cross section mounted rotatably within the chamber withtheir axes parallel and so shaped and spacedthat each drumdun ing rotation sweeps closely over corresponding arched roof and fioor portions and into the concavity of the adjacent face-of a preceding drum thereby scooping outmaterialinthe cavity and thereafter by further rotation presents it for being scooped by a succeeding drum, means for rotatingodd numbered drums while the even numbered are stationary and vice 'versa, and projecting means on the wallof the chamber in registering position withrespect toslots on the ends of thedrumswhereby sa id s lots;are

automatically de-clogged by saidlmeans as 13:

the drums rotate and thereby ensure a continuous gas passage along the chamber.

10. Agitating and conveying apparatus comprising a chamber with multiple arched roof and multiple inverted arched floor, a plurality of concave-faced impeller drums of polygonal cross section mounted rotatably within the chamber with their axes parallel and so shaped and spaced that each drum during rotation sweeps closely over corresponding arched roof and floor portions and into the concavity or" the adjacent face of a preceding drum thereby scooping out material in the cavity and thereafter by further rotation presentsit for being scoped by a succeeding drum, means for rotating odd numbered drums while the even numbered are stationary and vice versa, and substantially diamond shaped studs projecting from the 2 end wall of the chamber each in a symmetrical position with respect to the overlapping paths of adjacent drums whereby said studs pass through the de-clog correspondingly located slots in the ends of the drums as they 5 rotate.

11. Agitating and conveying apparatus comprising a chamber, a plurality of con cave-faced impeller drums of polygonalcrcss section mounted rotatably within the chamo ber with their axes parallel and so shaped and spaced that each drum during rotation sweeps into the concavity of the adjacent face of a preceding drum thereby scoping out material in the cavity and thereafter by further rotation presents it for being scooped by a succeeding drum, means for rotating odd numbered drums while the even numbered are stationary and vice versa, means for locking each drum while the material on one face thereof is being removed by a succeeding drum, and positive means for removing the material from the successive faces of the last impeller drum.

In testimony whereof, I havesigned my name to this specification.

MAXWELL McGUINNESS.

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