Drier.

Application filed May 4, 1909. Serial No. 493,839.

, To all whom it may concern:

Be it known that I, Marshall Whit----_—yATGH,--a'citizeivof'theUnited-States,residing at New York city,'in the county of Kings 5 and State of New York, have invented certain new and useful Improvements in Driers, of which the following is a specification.

In the designing oLJriers—heretofore many difficulties have been encountered, 10 chief among which has been that of subject-, ing the material to be treated to a constantly changing, fresh and unsaturated drying current of air or heated air without the formation of air pockets in the drier or per15 mitting air which has once been in contact with the material to again come in contact therewith. The formation of air pockets occurs in spaces within the drier which are not directly in the line of flow of the current 20 through the same, such pockets being composed of air in a more or less saturated condition, which tends- to impair the drying conditions which it is desired to maintain within the drier, and also is liable to again 25 be brought in contact with the material treated should a current empty all or a portion of a pocket. The difficulty of treating the. material in the drier to a current of air which comes into contact with the material 30 but once and then passes out of the drier, results also from the fact that any and all material inserted in the drier offers a resistance to the current of air passing through the same in a degree corresponding to the char35 acter of the material, the flow of the air being impeded, back currents formed, and the efficient operation of the drier otherwise interfered with.

It is the purpose of my invention to pro40 vide a drier which will be free both from the disadvantages and objections as above set forth, and other difficulties which have heretofore impaired the efficiency of driers of the class to which my invention relates.

In carrying out my invention I have provided a. drier (1) in which the material treated is subjected to the drying action of a constant flow of substantially unsaturated air, the air being removed from the drier 50 instantly upon having come in contact with the material; (2) in which the entire drying chamber throughout its whole extent receives an equal supply of constantly changing and substantially unsaturated air, every 55 portion of the material within the chamber being thus treated alike.

A drier embodying my invention is of novel design, form and construction and -comprises among its advantages novel supply and withdrawal of air, control of the 60 temperature of the same, distribution of the air within the drying chamber, manner of _treating4he'material, etc.

In the drawings herewith I have shown, and will hereafter describe, for the purpose 65 of illustration a drier embodying my invention which is more especially adapted for use in the drying of tobacco although it will readily be seen that a drier embodying my invention may be constructed for use in any 70 desired drying operation without departing from the spirit of my invention which consists in the design, arrangement, construction, combination and operation of parts as set forth in and falling within the scope of 75 the claims hereto appended.

In the drawings herewith like characters of reference denote like parts in all the figures thereof.

. Figure 1 represents a side view in eleva- ⁸⁰tion of a drier embodying my invention; Fig. 2 represents a plan view οϊ a drier embodying. my invention; Fig. 3 represents a detail, view in side elevation of the heater and air supply end of a drier embodying ⁸⁵my invention; Fig. 4 represents a detail plan view of the portion of the drier as shown in Fig. 3; Fig. 5 represents a detail view in end elevation of the supply and exhaust mechanism of a drier embodying my ⁹⁰invention, the drier chamber being shown in section; Fig. 6 represents a detail view in side elevation of an end of a drier embodying my invention, portions of the side of the drier being broken away and the distribu- ⁹⁵tion of air currents shown; Fig. 7 represents a detail view in side elevation of the opposite side of- the end of the drier shown in Fig. 6, portions of the side being removed; Fig. 8 represents a detail sectional 100 view in end elevation taken centrally through the end compartment of the drier as shown in Fig. 6 ; Fig. 9 represents a detail sectional view in end elevation taken centrally through the supply and exhaust end 105 of the second compartment of the drier as shown in Fig. 6. Fig. 10 represents a plan view of a portion of one of the perforated plates contained in a drier embodying my invention; the preferred arrangement of the HO perforations being shown therein.

A drier embodying my invention and

848,751 shown in Figs. 3, 4 and 5 The supply fan 18 draws air through a tempenng coil 1. and delivers it through hood 2» to supp y mssao-es 14 and 15, the air passing directly into temperate air passage 14, and ^ιηΐθ ξ^β' ⁷⁰heated air passage 15 through a_] second heater 20, passage 15 being preferably below passage 14. Low pressure steam is supplier through pipes 26 and live steam through pipes 27 through headers 28 to heating pipes ₇₅A ~ ίΑννΛΥ,Ληιη Ο’ ΟΛ1 I Ί9 ΠΠΠ tne heater 20. The heati’ng pipes 29 passing • . i nn ,_1M p^eferabiv arranged in llllo neater *v on pLviviauij &-.-_λ· indenendentlv valved sections each controlled by a hand valve 30. In this manner ₈₀it will be seen that temperate air is supplied directly to the temperate air passage 14, while the air passing into reheated air- passage 15 may be increased m tempengie to any desired degree by the operation of heatei .85 20 The fans 18 and 21 are prefeiably driven through chain driving connections 31 with motors 22 which are designed to operate the fans at equal capacities of supply θθ and exhaust. . «· · „

In order to gain the maximum efficiency of the drier the supply passages are uniform in size throughout their extension over the drying compartments, while the exhaust passage 16 is of uniformly increasing size, 95 being at its point of connection to the drying compartment farthest removed from the exhaust fan, of a size necessary to receive the exhaust air from, that compartment be ing of double the initial capacity at its point 100 of connection to the second compartment, of triple the capacity at the third compartment • and so on as the volume of exhaust an ; which it must receive is increased by its con) nection with additional drying compart- 105 ^m<The delivery of air to and exhaust of air from the drying compartments is shown in Fios. 6, 7, 8 and 9, the construction being such that a drier of the highest efficiency 110 and uniformity of operation is produced. In Fig 8, which illustrates, m the construction shown, the first drying compartment, the air is delivered through the ml^P^ sao-e 13 over the perforated plate 11 and in 115 a direction parallel with said plate between the same and the top of the drying compartment; in like manner the air„is~ drawn out through the exhaust passage 16 from be “een pSated plate 12 and the bottom of 120 the drying compartment. In the secon chamber, as shown in Fig. 9, the air is delivered below the plate 12 and exhausted from above plate 11. _o ,

By means of the construction as above de- 12» scribed each drying compartment is m effect divided into three chambers, one between adapted especially for use in the drying of I tobacco is shown in side elevation and in plan view in Figs. 1 and 2 respectively. As therein shown, the drier with top 1 and bot5 tom 2 is divided into ten drying compartments 3, two cooling compartments 4, and reordering compartment 5. The dividing walls 6 between compartments are provided with horizontal openings through which 10 passes the upper length of an endless conveyer apron 7, preferably of wire net, supported on drums 8 at the end of the drier and passing over rollers 9 intermediate its upper length, preferably at the points of its 15 passage through walls 6, the bearings o rollers 9 being preferably oufside of the drier. The lower length of the ap.on < passes underneath the drier, the direction of travel of the upper length of the apron : 20 being from left to right. At each opening ;

in walls 6 a light swinging shutter 10 is provided adapted to rest on the apron and substantially close the opening between compartments except for the passage of the apron. Over the apron 7 and adjacent thereto is placed a perforated plate 11, a second perforated plate 12 being in a h <e manner placed underneath the apron. Each drying compartment 3 is connected by an inlet passage 13 with temperate air supply 14 and reheated air supply 15 above th drier, an exhaust passage 16 connecting each drying compartment with the exhaust pipe 17’underneath the drier. The inlet passages 35 13 enter alternate chambers above plate 11 ³⁵ and below plate 12, th. exhaust parges being arranged accordingly. A supply fan 18 draws the air supply through a tempering coil 19 and delivers it to supply pipes 40 14 and 15, a second heater or reheater 20 being placed at the entrance to ^r^^ted air supply pipe 15. An exhaust fan 21 withdraws the/ air through exhaust pipe 17. Motors 22 of equal capacity are preferably used to operate the fans. Cooling compartments 4 are connected with a cold air supply duct 23, the air being withdrawn through exhaust passages 16 connected with exhaust pipe 17. Over the apron conveyer 7 at tne delivery end of the drier is located a vapor ^h°It will readily be apparent from the detail description of my invention hereafter that the above general design of a drier ^ma7 _.

changed or modified as desired to^ accord with the purpose for which it is to be used, the capacity and drying effect desired,etc., without departing from the spirit of my invention · the general form of drier as above designed having been found in practice to be of e^Sal value in the drying of tobacco on a large scale.

heSs^drandⁱⁿsup5y’ and exhaust fans as pipes 27 through headers 2» to neavuig i»!^ ₉%_ssi„g in£tb« «η Lx

--------- ----- divided HILO Illiev Y t 7 ’ 7 17 'SiiSnw the gjrg^^™7±5ί’ JS SueTfens as I forated plates through which the apron eon048,781

Veyer passes, a third between the lower perforated plate and the bottom of the compartment. The first or upper chamber constitutes an air distributing chamber, the third, or lower a “distributing” exhaust chamber or vice versa, and the middle a drying chamber? The upper plate 11 is necessarily farther removed from the conveyer belt than the lower plate 12 since the tobacco to be dried is piled upon the conveyer.^. The perforations in the plates 11 and 12 are preferably arranged in rows, the perforations of each row being offset or out ot line with the perforations in adjacent rows (see Fig 10). Each inlet passage 13 .. connects with both temperate air supply 14 and reheated air supply 15 through, connecting pipes 321 in which are placed pivoted dampers 33 which are connected by chain 34 and may be regulated simultaneously to . supply temperate air and reheated air in desired volumes. Each inlet passage thus forms a mixing passage for the temperate and reheated air. Pivoted dampers 35 are also placed in inlet passages 13 and exhaust passages 16, each pair being connected by chain 36 in such a manner that they may be simultaneously controlled to regulate the supply and exhaust equally. In the second chamber and m all chambers where the supply to the drying compartment is from below dampers 35 in inlet Nnd exhaust passages 13 and 16 are simultaneously controlled through being mounted in the same horizontal plane on a shaft 37. The side of the drying compartments and supply passages opposite the'supply inlet and exhaust outlet is formed in removable panels 38 which may be readily removed to expose the 40 interior of the drier. The lower length of the conveyer apron being exposed underneath the drier,' any damage thereto may be instantly noted and repaired. The drier is supported on standards 39, in which stand45 ards outside of the drier are also provided bearings for the ends of the rollers 9.

The supply and withdrawal of air is as follows: The fans being operated at equal capacities, the supply fan delivers a constant now of temperate air to the temperate air passage and reheated air to the re leated air passage, such temperate air and reheated air being mixed m the inlet passage to each drying compartment before entering the compartment. The air being delivered in each compartment over or under a perforated plate and m a direction parallel therewith at a considerable velocity, flows at once to the opposite end of the air distributing chamber^at the same time expanding and tilling the chamber in its entire width after leaving the constricted mouth of the inlet passage. Upon striking the opposite end wall of the distributing chamber the air backs or piles tip, the entire chamber over or I under every portion of the perforated plate being thus supplied with air. Owing to the comparatively small size of the air. distributing chamber and the manner of delivery of U? ^{the a descr}₁^ifced supply occurs in a 7 0 .space of time and is substantially completed before the action of the exhaust fan from the opposite side of the plate through the drymg chamber draws the air down ot up through the plate. The action of the ex- 75 haust having become effective, the air is drawn through the plate ovei· its entire extent m fine streams and immediately strikes the material to be dried; the material being E θ^Π TJ^{eyer a}P^ron and filling the 80 grater part of the space between the apron and the upper plate, and the lower plate being adjacent to the apron. The air upon owin^ln? J® ^m?^{terial is not} diffused, f>ut, owing to the exhaust through the perforated °£^th? °PP^0Slt® side of the apron con, ,^eyer’ streams of air are drawn through the material substantially unbroken, every SS?¹¹ n^he .^raat?^riai being subjected ^ally at all points in its course of travel through the drier to the drying effect of unsaturated, constantly flowing, heated air which is immediately removed after passing through the material. In a like manner the formation of a comparatively small air distributing exhaust chamber with the .flow of he exhaust parallel to the perforated plate through which the air is drawn, provides for an equal withdrawal of air at all the perforaJf?⁸ °? ^S?^{ld pl}.^a,^te’‘ ^tbe construction of the loo exhaust pipe with uniformly increasing capacity insuring an equal withdrawal of air ^tr™ each drying compartment.

Ihe drying operation above described has proved to be especially efficient for use in 105 connection with tobacco which permits of the passage of the air through it in fine, spaced streams. Other material as desired may, however, be efficiently treated in the same manner.

. It will be seen that a drier embodying· mv invention provides uniform and complete distribution of air supply in a distributing chamber, the passage of the air in spaced ana positively directed streams through the entire extent of the drying chamber and a uni-° formly distributed withdrawal in the exhaust chamber. The tendency of the air to pass directly from inlet to outlet is overcome, the resistance offered by the material through • which the air must pass is provided against, and the use of saturated air or its presence m the dtying chamber is rendered irnposThe temperature of the air in the supply passages or inlet passages may be governed hy the use of necessary thermometers or indicating devices and the proper regulation of the mixing and throttling dampers for each drying compartment independent of the 130

110

115

120

125

Θ48,7δ1 saee, an outlet from said withdrawal chamber into said air withdrawal passage, means for supplying air to the distributing chamber through the inlet, and means for withdrawing air from , the withdrawal chamber 70 through the outlet. , ·_

In a drier, in combination, a dryi g tions forming a portion of the distributing chamber and Jbe drying chamber, a second plate provided with Per forations forming a portion of wall between the drying chamber and the withdrawal chamber, an inlet to the distributing I chamber, an outlet from the J^lth^awal chamber, and means for causing a flow ot air into said distributing chamber in a direction substantially parallel with the perto rated plate between the distributing cham^to₅ ΐ . drying compartment comprising an ⁹⁰ chamber, a drying chamber and an air-witn drawal chamber arranged substantially in parallelism, a plate provided ^h Perforations forming a portion of the the distributing chamber and the drying chamber, a second plate provided Withj?er forations forming a portion of th wall be tween the drying chamber and the withdrawal chamber, an inlet to the distributing .₀₀Smber, an ^th? ’ίΐΓοΐ chamber and means for causing a flow of air from the withdrawal chamber in a direction substantially parallel with the perforated plate between the withdrawal cha ber and the drying.chamber. . ·

In a drier, m combination, a ary g compartment, comprising an ing chamber', a drying chamber, andnnai withdrawal chamber arranged substantiaUy in parallelism, a plate provided.with per. il ¹ forations forming a portion of the wall beween tne aisu’iuuuuig —-- .

¹ ing chamber, a second plate. P^r0Vld®£ perforation^ forming a portion of the waU Γ . ji nl-iomhpr n.nd tne W1VH J ^x

I the distributing chamber, an outlet from the chamber, means for causing a flow o: air

I the distributing chamber in a direction sXantW ^with the perforated 120 plate between the distributing chamber and

S^Tdrying £ £™ ’ ¹ chamber and the drying chamber.

7. In a drier, m combination, a dry g compartment comprising an air-distributothers; in like manner the volume of air supplied any one compartment may be independently regulated.

The tobacco being placed on the apron - conveyer (as indicated in Fig. 6) passes ⁵ through successive drying compartments, is cooled in the cooling compartments, is treated in the reordering compartments, as is usual in the handling of tobacco, to prevent excessive dryness, and is delivered at the op¹⁰ pS end of the drier, the slight vapor or steam arising from the tobacco being drawn off through the vapor hood.

A drier embodying my invention is of ₁₅ maximum capacity, and of absolutely JT ¹⁵ form operation with a minimum ot time, labor and expense required for its care and ^^hasT before been stated the supply of _M reheated air and of temperate air admitted ²⁰ to the inlet or mixing passage of each com- | partment may be controlled by simultaneous operation of dampers 33 by means of .chain 34 and it will be noted as shown that the 25 movement of chain 34 to, dose one dam²⁵ ner 33 opens the second damper 33 to an. equal degree; thus the exact.volumes of.reheated air and temperate air desired may be obtained and any desired temperature 30 maintained in each of the drying compartments independent of the others.