US2132972A - Drier - Google Patents

Description

Oct. 11, 1938. H. l.; SCHMIDT DRIER Filed March 27, 19257 lllttlnt. H

Patented Oct.' l1, 1938 l UNifTiaii)v .STATES nsriow L. schmidt, Milwaukee, wis., mignonto The Heil Co., a corporation of Wisconsin application Maren 27,

c 4 Claims.

My present invention relates in general'to improvements in the art of heating, and relates4 'more specifically to improvements in the construction and operation of internally heated drums having peripheral annular supporting ele- 5 ments or tires coacting with rotary members such as rollers to rotatably support the drums.

Generally defined, an object-of the present invention is to provide an improved mounting. for rotary cylinders or the like, `and improved instrumentalities for preventing excessive heating of the supporting' elements.

It has heretofore been common commercial practice to support the drumsv of rotary driers, l kilns and the like upon tires secured to the outer i 3 shells and coacting with rollers journaled in stationary supporting structure. Due'to the intense internal heat, the supporting tires are frequently subjected to sufficiently high temperatures to warp and otherwise distort the same, thereby not only producing irregular lrotation of the drums but also subjecting Vthe tires to excessive stress and possible rupture. It is however desirable for structural reasons, to attach the tires directly to the shell of the drum near the end heads, and

.in extremely long-shells intermediate' tires may also be required.A In most devices of this general class, it is also undesirable to provide deep pockets near the end heads, withinwl'iich material tends to accumulate, but dishing'of the heads in vorder to eliminate such pockets is rather costly and objectionable for this reason.

My present invention therefore contemplates the provision of improved means for preventing excessive heating of the supporting tires oi a drier drum or the like, due to internal heat.

My invention also contemplatesthe provision of improved means lfor eliminating undesirably deep pockets near-the end heads of a drum, within which material tends to lodge. l,

' The Iinvention furthermore contemplates the provision of simple and eiective structure for insulating or-segregating the supporting tires voil! a drier drum 'fromthe internal heated zones by ventilated air spaces, while at the same time obviating deep material collectingcorners; and

` pockets within the shell of the drum.

` These and other specic objects and advantages of the present invention will be apparent from the following detailed description.

A clear conception of embodiments ofthe features constituting my present improvement, and of the mode of constructing "and of operating driers built in accordance with this invent/ion, s maybe had by referring to thedrawing accompanying and forming a part of this specication fan Il is adapted to constantly create a now of 1937, seria. No. 133,365V

roi. 3.4-5)

wherein like reference characters designate the same or similar parts in the several views.

Fig. 1 is a substantially longitudinal vertical section through a rotary drierv embodying the improvement;-

Fig. 2 is a part sectional end view of the drier 5` of Fig. 1, lookingtowardthe feed end thereof Fig. 3 is a considerably enlarged section taken through the feed en d corner of the drier drum of Fig. 1; and

' Fig. 4 is a similarly enlarged seetion'through 10 the feed end corner of a slightly modiijled asf semblage. y

While my invention has been shown and described herein as being specifically applied to a particular type of drier drum and for the specic 15 purpose of protecting a smooth annular periph.-

. leral tire from detrimental effects of internal heat,

it is not the .intent to thereby unnecessarily re;v strict the scope, since the improvement is also applicable to other types of rotary drum drives 20 and for the protection of such drives against any ki'nri of temperature changes. ,c

Referring to the drawing,- the improved drier shown ratherdiagrammatically in Figs. 1 and 2, comprises in general a drum assemblage` consist- 25 ing of three concentric elongated shells 8, "I, 8 and end closure heads 9, I0, II coacting therel with; a hot gas supply duct or pipe I2 and a material supply spout I3 communicatingwlth the feed end ofthe inner shell. 8; an outlet pipe Il 30 communicating with vthe' dischargel end of the outer shell 8 and with ari exhaust fan I5; peripheral tires I8 secured' to the opposite ends of the outer shell) adjacent to the end heads 9, III; and rota-ry supporting rollers I1 coacting with the 35 tires I 6 and b'eing journaled in the bearings I8ki 'carriedby suitable foundation beams I9. The gas supply pipe I2 is fixed and communicates with anysuitable source of hot'gas, and the material supply spout *I3 is also stationary and may be 40 provided with a rotor as Ashown for regulating the delivery of fibrous. or granular'material into the innerdrum shell 8 vwith the heated' gases. The outlet pipe I4 is also stationary, and the exhaust 45 mixed gas and fibrous material through the re-r volving drum assemblage and tov deliver the treated mixture toa suitable separator. The interiors of the shells 0, 1. 8 may also be provided with 50 internal, nights for showering the solid particles across the interiors of these shellsgso as -to en- .hance the drying action, but these ilightsform no part of the present in ventio'n and have there- Iorebeen omitted in order to avoid confusion.

CTL

, The sheus s, 1, s and the end heads '91, lo,

may bevformed of sheet metal and are preferably closes an end of the shell 1.- The opposite end f the intermediate shell 1 is supported concentrically of the outer shell 8 by means of a similar ring 23 and gussets 24, near the end head 9;

and the space between the end heads I0, I I yhas a series of radial ights 25 therein which cooperate with a cone 26 on the exterior of the end head Il to deliver the treated material into'the outlet pipe I4. The outer end head I0 may alsobe pro-- vided with a sealing plate 20 coacting with the l pipe I4, anda deflecting vcone 21 may also be provided onthe inner face of the end head Il, but these details of construction are relatively unimportant so. far as my present invention is concerned. Itis to be noted, however, that the relative mounting of the concentric shells 6, 1, 8

:and the location of the end heads 9,- I0, II, is .A such that acontinuous circuit'ous path is pro-v vided in the drum assemblage, extending from the inlet pipe I2 to the outlet pipe I4, and the gussets 22, 24 as well as the flights 25 are radially disposed.

The tires I6 vare rigidly attached, as by welding, to the periphery of the outer shell 8, adjacent to the end heads 9, I 0,'and the gusset 24 and -ilights'25 extend into theannular corners formed by the end heads andthe shell 8 directly within these tires. The shelli3 is also embraced by a jacket 28 of insulating material, which-extends 40 @from one tire I6 to the other, and the end heads 9, I0 may also be covered withr like linsulation, if so desired. In accordance with the present invention, inorder to segregate the tires I6 from the heated interior`of the drum, a series of segment plates 29 are inserted across the corners of the outer shell' 8 between the successive radial gussets 24 and flights 25,` to ,provide substantially annular air'spaces 30 having substantiallytriv angular cross-section, as clearly shown in Fig. 3.

lIn order to vent`these annular spaces '36, the end heads 9, I0 are provided with' openings 3l whereby the heated air may escape and cool air may ,enter the spaces 36. Besides providing insulating air spaces 36, these segment plates v29 also eliminate the deeppockets exposed to the Vdrum interior, and within which solid particles might other- I wise tend to accumulate, and these 'pockets are obviously done away'with without necessityyof Adisliing the end heads 9, I0.

The segment plates 29 may be eitherstraight or curved as shown, and the spaces 30 may be ad ditionally vented as in Fig. ,4, by shortening'the y insulating jacket 28 andfby providing other openings 32 in the shell 6 laterally adjacent 'tothe tires I6. Theradial gussets 24 and flights'25 ex- .tending into the spaces 30, will'then act as fan blades 'tending to draw freshl air into the side' .openings 3I vand to deliver-.the I peripheral openings 32.

During normal operation ofthe improved drier, heated gas from Aany suitable source is being constantly delivered into the inlet end of the central shell s throughqthe pipelz, together with the material which is to be treated, this material being constantly discharged inregulated 'quant1-- air through the shell providedwith end heads and an inner shell ties from the supply spout I3 into the entering stream of hot gas. The drier drum is being constantly rotated from any suitable source of power, throughthe supporting rollers I1 which frictionally engage the tires I6. The suction fan I5 is operating to' constantly draw the mixture of material and ,gases through the shells 6, 'I, B in succession as indicated by the arrows inrFig. 1,` and the ilights 25 normally function to deliver the nally treated material' into the discharge pipe I 4 from whence it is withdrawn by the fan I5 and is delivered to the separator. material admitted from the feed spout I 3 is constantly dried and is delivered in dried condition to a separator or other point of utilization.

Because of the relatively high temperature of the gases passing through the drum, the shell 8 and end heads 9, I6 will naturally become heated. In order to prevent the tires I6 from becoming excessively heated, I have provided the segment plates 29 which form the chambers or spaces 30 segregating the tires I6, from the heated interior of the drum. While the air within the spaces 30 disperse -=this heat and will thereby prevent excessive heating of the tires I6. The plates 29, besides providing substantially annular insulating air spaces for the tires I6, also eliminate deep pockets between the successive radial v nes or plates at the corners formed by the junctions of the end heads 9 with the shell 6, thereby preventing the material beingtreated from accumulating at these corners. The\provision of the openings 3I does not materially weaken the end heads 9, I 0, and if additional ventilation .of the spaces 30 is required, openings 32 such as shown in Fig. 4, may also be provided.

From the foregoing detailed description, it will be apparent. that the present invention provides simple and highly eflicient means for protecting the tires I6 against excessive heating due to the vhigh internal temperatures prevailing within the drum. The tire insulating means also functions to'prevent accumulation-of material in the corners of the drum structure, and all of these advantageous resultsy are obtained by merely placing the segment plates 29 diagonally across the corners and by`providing .ventilatingopenings 3|. ,The assemblage can obviously be produced at extremely moderate cost and vfunctions automatically to produce the desired results. l

It should be understood that it is not desired to limit thisinvention to the exact details of In this manner, the

may tend to heat, the openings 3| will quickly construction or to the precise mode of operation herein shown and described, for variousmodi cations within the scope of the claims may occurj to persons skilled in the art.

` 1. In combination, an internally heated drum .having outer and inner shells, an annular series 'of radial plates for .supporting said inner shell from said outer shell, a tire secured to the periphery of said outer shell-adjacent to said plates, anda series of segment platesv connecting the successive 'supporting plates and providing an air space between saidtire and the heated drum interior. "i

2. In combination,a drum having an outerl lwith said outer shell, a tire secured to each end oi' said outer shell near the adjacent end head,

and a series ofsegment plates connecting the aisaova successiveradial plates near each endhead to p rovide air spaes between said tires .and the interior of saidv drum.

3. In combination, a rotars1 drum having an annular end corner separated into segments by a series of plates, an annular driving element secured to said drum at said corner, and an annular series of segment plates ,connecting said rst mentioned plates to provide an a'nnular air chamber at said comer separating said element frorn thedrum interior. Y

'42 1x1-combination, .a cy11ndricu drum having at each end an annular corner divided into segments by a series of radialA plates, -an annular -tire'secured tothe periphery of said? drum at each` of the cornered ends' thereof, and annular HARLQW L. scm/nur.

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