US2119594A - Egg dehydrator - Google Patents

Description

June- 7, 1938. C. MGLEAN l 2,119,594 n EGG DEHYDRATOR Filed Dec. 6', 1934 4 sheets-sheet s IN V EN TOR. 6M'

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June 7,1938;

C.M6LEAN EGG DEHYDRATOR Filed Dec. e, 1934l 4 sheets-sheet 4 VENT R ma w ATTORNEYS.

Patented June 7.19378v y y A v l UNITED STATES PATENT OFFICE l Y EGG DEHYDRATOB,

Charles McLean, Berkeley, Calif. Application December 6, 1934, SerlalNo. 756,312

'a claims. (ci. 15s-'ii e e This invention relates to egg dehydrators for the feeding apparatus `illustrated in Fig. 1, showdehydrating or desiccating eggs or any other ing the details of construction thereof. more or less viscous substance, or any substance Fig. 3 is a plan view of the feeding apparatus containing moisture. illustrated in Fig. 2.

The machine is of the class which comprises Fig. 4 is a sectional view of the feeding appa- 5 generally an endless metallic-belt, means for deratus, taken on line IV--IV of Fig. 3. livering the iiuid to be dried to the'belt as it Fig. 5' is an enlarged viewof one end of the travels, means for heating or otherwise causing distributing roller which forms a part of the feeddesiccation of the fluid on the belt, and means for ing apparatus illustrated in Figs. 2, 3, and 4. l

removing the finished product. The efliciency of Fig. 6 is a view in side elevation of the scrap- 10 a machine of this class depends greatly upon its ing mechanism. ability to operate continuously and uniformly Fig. 'I isa plan'view of thescraping mechanism over an indefinite period of time. This is parillustrated in Fig. 6.

ticularly true, owing to the practice of operating Fig. 8 is an enlarged view of the mechanism the machine under vacuum to assist in the de- ,employed'for maintaining the belt under tension'ls hydration of the product. Whenever it is necesand adjusting the tension on the belt to compen-' sary to cease operation to repair, adjust or clean 'sate for variations due to uneven expansion and the machine, it is necessary to break the vacuum contraction. in the housing which encases the machine and Fig. 9 is a sectional view, takenon the line reestablish the vacuum at a; considerable loss in IX--IX of Fig.' 8.

time and energy. l .v The machine, as illustrated in the drawings,

The metallic beit" employed travels over a pair comprises an elongated housing ilsupported on of spaced cylindrical drums, and in the event of leg members Il which may besuitably secured to uneven distributionl of heat, which may be caused the iioor as by pins i! and which is insulated by an uneven layer of fluid on the belt or failure as shown to prevent unnecessary-loss of heat. One 25 to remove parts of the dried product, the belt will end of the housing is closed by a door I3, supbecome distorted. Upon distortion, caused by ported on hinges i4 and provided with a gasket irregular expansion and contraction, the beit i5 vof rubber or-other suitable gasket'material tends tooverride the edges of the drums with the for the purpose .0f foi-miba an air-tight seal. A

result that operation must be discontinued. Caster I3 may be Provided at the bOttOm 0f the 30V It is, therefore, the object of the present in- 091' t0 engage the n01' and Pawn? 'support vention to provide an improved egg dehydratOr ggl'seight or th? door as it is swung Pon itsin which the iluid to be dried is uniformly spread upon a drying beltand thoroughly cleaned therewitmn the housing I. an endless metallic belt riod; and to provide means for impartingv heat to the belt uniformly throughout its entire-width; gg fmxnch ma jmmls n centran f re received b bearings 2i and and to provide means for adjusting the drums 22 so that upon rotation of tige drums as they over rides,'1n event of dlstorare supported these bearings the may be tion, without'the necessity 0f breaking the vacaused to travel continuously within the nouso uum in which the machine operates; and toproing, These bearings which support the drums vide further novel-featuresA of construction that are mounted on an elongated'framewhich is will promote eflicient,.continuous, uniform operaillustrated as formed of channel iron andl which tion. y is provided with casters 24 which ride on tracks One form of my invention is exemplified in the 2l supported by' brackets 2O to the inner accompanying drawings, to which reference is" wall of the housing.`

made in thefoilowing specification. In the speci- The atmosphere .within the housing is maincation further objects and advantages of the mined at low pressure through suitable pump v invention aremade ppalentlmeans (not shown) connected with pipe, suchas 50,

In the drawingsillustrated at 21, communicating lwith' the intc- Fig. 1 is a. longitudinal, :vertical section of an lrior .of the housing so that-"the drying operation egg dehydratorconstructed 'in accordance with 1 may take place with as little .heat as necessary my invention. f and without danger ofcooking .0r burning the 5 Fig. 2 is en emerged view in side elevation orproduct being dried.

will impart rotation to the other Suitable gauge means, such as illustrated at 2l, may be provided for determining the condition of vacuum within the housing,'and temperature, registering gauges, such .as illustrated at 29 and 30, are provided forregistering the exact temperature at various points within the machine.

'Ihe fluid that is to undergo desiccation is delivered through a pipe 3| and nozzles 32 to the feed mechanism, generally indicated at 33, by meansofwhich it isv evenly distributed upon the belt in a manner to be more fully described and carried throughoutA substantially the entire length of the belt in a heated atmosphere of low pressure for a time sufllcient to accomplish the desired desiccation. whereupon it is removed from the belt by scrapingmechanism, generally indicated at 34, to fallagainst a chute 35, by means of which it is directed into a receptacle il. The receptacle 36 may also be supported on casters 31 bearing on rails 38 to facilitate its removal from the housing when the` door is opened.,

In order to impart rotation to the drums which carry the belt, a drive shaft 39,`extending transversely of the housing, projects through one wall thereof, Where it Amay be connected with any suitable source of power (not shown). A gear 40 is carried vby this drive shaft and meshes with a gear 4I lsecured to the drum I 8, so that upon rotation of the drive shaft this drum will be caused to. rotate and move the belt which drum' through frictional contact therewith.

During` the operation of the machine, the'interior. of "the housing may be illuminated by electric lights, such' as illustrated at 42, and

' the process may be observed through suitable positions..

glass-covered ports, such as illustrated at 43, arranged in the wall of the housing at convenient The ,interior of the housing may be heated by steam, hot'wat'er, electricity, or any vother suitable medium, and the apparatus shown in the.

drawings is designed for the use of steam. The main heating element comprises a stationary steam table 44 positioned directly beneath the upper flight of the belt i1. 'I'his table is provided interiorly with opposed bailles which cause a more or less retarded flow of the heating medium therethrough. lThe top surface of the table is fiat and preferably of slightly greater width than the belt which' passes Aover the table in direct contact therewith so that the amount of vheat A,transferred to the material on the belt will be`as great as possible. 'I'he direct contact' between the steam table and the belt also inf sures equal .heating of the belt throughout its width,"as it eliminates the possibility of air currents between the belt and table which would interfere with the uniform heating of the belt. A similar table to that shown at 44 may also be' provided directlyabove the` lower flight oi.' the belt, as illustrated vat 45.`

Steam (from a source 'of supply not shown) is` delivered through a pipe 48 which enters the housing horizontally above the belt, drops vertically downwardly, as at 41, and .again passes rearwardlyand horizontally parallel to the axes *of the drums i8 and IS. Branch lines 48A and 4 5' supply steam to the forward ends of the' steam 'tables 4 4 and, which steam passes through the tables lengthwise, discharging at the opposite ends thereof-'through the. lines 50 .and 5| to enter a main discharge line 52,/by means of which the steam is carried out of the housing.

In the event that it'is desired to heat the belt as it passes over the drums, I have provided means for supplying steam to the interior of the drums. To accomplish this, the journals 20 of the drums are concentrically bored to permit pipes-to enter the drums from the main' drums and gathers at the bottom thereof is forced outwardly by the pressure of the incoming steam; and, furthermore, this positioning of the outlet opening causes the steam to-circulate and lill the entire drum rather than to pass directly through the center of the drum.

The steam supply line is provided with a union yconnection 56 and a similar union 51 is provided in the discharge line. Upon .disconnection of the unions 56 and 51 theentire unit, including the belt, drums, feed mechanism and scraping mechanism, is free to roll out of the housing vI on the tracks 25. Outside tracks (not shown) may be positioned to receive the unit. en thus removed from the housing the unit may be thoroughly cleaned with steam under high pressure, or any other suitable cleansing medium,

and the interior ofthe housing is also unobstructed to facilitate repairing or cleaning.

When the interior of the housing is washed or steam-cleaned, the surplus moisture may Vbe drawn off at the rear end through a pipe 8 which serves as a drain. As previously stated, the material to be desiccated is delivered to the belt I1 in fluid or pasty form by means of the feedmechanism, generally indicated at 33, the construction of which is shown in detail in Figs. 2, 3, and 4. 'I'his feed mechanism comprises a box to which the fluid is delivered through the nozzles 32, consisting of side Walls 59 and a back wall 60 positioned over the belt. The lower edges of the side walls and back wall are providedl with sealing members 6I of rubber or other similar material secured to the box by means o1' screws, such as indicated at 62. Across the back wall of the box an anglemember 63 supports downwardly extending brackets 64 Whichcarry rollersl65- underlying the edges of the belt to maintain the box in close contact therewith. The belt itself forms the bottom ofthe boxand the front wall thereof consists of a distributing drum 66. 'Ihe distributing drum 66 is rotatable and, therefore,

.can not be securely fastenedto the side walls 'of the box, but a duid-tight seal is produced by cutting the front ends of the side walls arcuately to fit over the heads of the drum, as shown,`

and byproviding metal plates 61 secured to the inner sides of the ends ofthe box and arcuately cutat their forward edges to be received in milled annular slots 68 in the heads of the' drum, as illustrated in Figs. 2, 3 and 4. The said slots are of substantially the Asame width as the metal members 61 vand the close fit of these members, together with the motion due to rotation 'of the drum, prevents the escape of fluid at these points.-

The distributing drum 66 is mounted for rotation in conventional roller bearings 69, the housings for these bearings being formed on bearing arms 10, pivotally supported on pins 1| to permit raising and lowering of the drum to vary the thickness of the uid spread upon the belt. Springs 12 normally urge the distributing drum toward the belt, and cams 13, xed to a camactuating shaft 14, bear against the bearing arms 10 .to move them against the tension of the springs 12 and thus vary the space between the drum and the belt. The cam-actuating shaft 14 extends transversely of the machine and one ofits ends may be squared for the reception of a wrench to'adjust the position of the. cams 13. The central part of thisshaft may also serve to carry a scraper blade 15, as shown in Figs. 2 and 3, for the purpose of cleaning the distributing drum as it rotates; and the tension on scraper blade may be adjusted through a crank arm 18 connected by means of a link 11 to a lever 18 on a rotatable shaft 19 (Figs. 3 and 4).

The belt1 I1 is maintained at a constant level directly beneath the distributing drum by means of a roller 80 carried for rotation by journals 8| in bearings 82 at its ends. The roller 80 is'rotated by a chain 83 (see Fig. l)` which drives a sprocket 84 xed to the roller shaft, which chain is driven by a sprocket 85 carried bythe main drum I9. The distributing drum is rotated by a gear 86 which meshes with a gear 81 secured to the roller shaft to rotate with the roller.

It is desirable to co'ol the surface of the distributing drum in order to prevent the fluid from drying or coagulating as it contacts the surface of the drum. To accomplish this I have provided means for circulating cold water through the drum while the machine is in operation. said means comprises an inlet tube 88 entering the drum axially at one end thereof and supplying water torthe interior of the drum through ports 89, which water, after passing through the interior of the drum, exits through similar ports 90 and through an outlet tube 9| arranged concentricaliy Within the tube 88 and surrounded by a sealing gasket 92 to prevent mixture of the incoming and outgoing water. The tubes 88 and 9| are, of course, non-rotatable and preferably will be carried directly outwardly through theV wall of the vacuum` chamber by suitable conventional connections V(not shown). A rotary springpressed seal 93 is Vprovided. to prevent escape of the cooling water between the surfaces of the non-rotatable tube 88 and the rotatable head of the drum.

Upon operation of the machine, the fluid to be desiccated entering through the nozzles 32 is deposited in the 'feed box, preferably after passing over a distributing. plate, such as'illustrated at 94, which is provided with spaced drain lips 95. Due to the heated and partially evacuated atmosphere, this fiuid, particularly if it isan egg, tends towardebulliency and is in a more or less agitated statewithin the feed box. Upon coming in contact withthe cooled distributing drum, the fluid is restored to a quiet state and as it is carried by the belt from the feed box under the y distributing' drum, this drum spreads it in an evenlayer, whereupon it is subjected to uniform treatment during its passage over the heated table and through the atmosphere ofheat and low pressure. Thel temperature and pressure Within the housing and the speed' ofv travel of the belt upon which vthe fluid is spread are so r'egulatedtha't the fluid carried by the belt will have been suitablyand uniformly treated in the The their ends.

` screws I I2.

period of time that is required 'for it te traveI from the feed mechanism to the scraper mech-A anism, generally indicated at 34, by means of which it is removed'from the belt.

This scraper mechanism is shown in detail in Figs. 6 and '1, and comprises a plurality of relatively narrow scraper blades 96 positioned side by side. vidual bearing member 91, which bearing members `are supported for radial adjustment on a tube 98 so that their scraping edges may rest against the belt, as best shown in Fig. 6.

The bearing members are held against endwise movement on the tube 98 by means of a collar 99 secured to one end of said tube and a collar secured to the opposite end thereof. The tube 98 is mounted for sliding movement on a rotatable bar |0I which extends transversely of the belt and is journaled in suitable bearings |02. A cylindrical cam |03, provided with a cam groove |04, is secured to the bar IOI, and the collar 99 is provided with an arm carrying a dog |06 which rides in the said cam groove |04. A bracket |01 is providedwith a milled slot |08 which receives the lower edge of the arm |05 for sliding movement, thus preventing rotation of the tube 98. -The outer end of the bar |0| is fittedwith a sprocket |09, which sprocket is engaged and driven by the same chain 83 which drives the distributing drum 66, as referred to aboveand illustrated in Fig. 1. Upon rotation of the bar |`0I the cam |03 is rotated and through engagement of the arm |05 with the cam groove |04, the tube which supports the scraper blades is caused to oscillate transversely of the belt. This oscillating movement causes the scraping edges of the blades to describe a zig-zag path on the belt, and a slicing action is produced which is considerably more effective in-removing the desiccated product from the belt than is a simple scraping action.

Each blade is provided `with an indi-4 y Each scraper blade is' held in contact with the belt by means of a spring I|0 secured to the scraper bearing by a bolt I|| at its upper end, and fitted withJ an adjusting screw ||2 at its lower end, which screw bears against the top surface of the blade. The tension may be simultaneously increased on all of the blades by means of `a transversely extending rotatable cam bar |I3 which engages the springs ||0 intermediate The portion of this cam bar engaging the springs is formed eccentrically with respect to the axis of rotation of the bar, so that upon rotation the pressure on the` springs may be increased or decreased. 'I'he tension of the springs may be varied individually and independ-f ently of the cam bar by means of the adjusting A plurality of narrowblades, as i1- lustrated, has been found to be most effective in removing the product from the belt, as whena single blade is employed it is `found that slight ir- -regularities in the surface of the belt or the hardness of the product that is being removed will result in incomplete scraping and the building up of hard masses of the product' which become i overcooked upon ybeing repeatedly subjected to the drying temperature-.

With the heating means and described above there is little opportunity for the metal belt to become distorted, due to variation in temperature throughout its width. However, in the event of any such distortion I have provided means for adjusting the bearings which support the main drum I9, which means may be feed mechanism operated from the exterior of the housing, without the necessity` of breaking the vacuum, to

counteract any tendency of the belt to override the edges of the drums. This means comprises an adjustable tension device which may be apend and provided withA a head H6 at its opposite end. A compression spring |I1 is interposed between the head IIS and the saddle |I4, and as the opposite end ofthe bar ||5 is anchored to the frame, this spring exerts a force which tends to tighten the belt at all times. By varying the pressure on the spring III of one bearing, the entire drum may be thrown slightly out of line to counteract the tendency of the belt to ride off in the event of any unevenness caused by temperature variations. The threaded end of the bar H5 is-anchored to the channel by a bearing member I'I'I secured thereto by bolts, as shown. This bearing member carries foi'- rotation an elongated nut ||9 threaded on the bar and provided at one of its ends with a bevel gear |20. The bevel gear |20 is in mesh with a second bevel gear |2| having an integrally formed trunnion supported in a bearing |22 carried by a bracket |23. This trunnion may be provided with a squared hole at its end for the reception of the squared end of a crank-shaft |24 extending outwardly through the wall of the housing through a conventional stumng-box |25,.and tted at its outer end with a hand crank |28. Upon rotation of this crank the bevel gear |2|, at -its inner end, rotates the bevel gear on the nut H9, thereby lfeeding the rod ||5 in either direction to increase or decrease the pressure on the spring 1, as desired. In order to permit vthis adjustment of the drum, the steam discharge line 54, illustrated in Fig. 1, is preferably made of rubber or other lflexible material, so that the otherwise rigid pipe connections will not be broken due to movement of the drum.

When it is desired to remove the entire unit from the housing-for cleaning, the crank shaft |24 may be pulled outwardly through its stuifing box for a distance sufficient to remove its squared end from the socket in the bevel gear I2 I.

-While I have shown and described a speciilc form of my invention, it is, of course, to be understood that various changes may be resorted to in the arrangement and construction of its several parts within the spirit and scope of the appended claims.

Having described my invention, what 1. In combination with a belt for conveying iiuid matter to be dried, means for delivering such matter to the b elt, a box-like structure overlying the belt at the point of delivery of matter thereto, means forming 'a seal between the lower edges of the box-like structure and the belt to conne the matter to the belt, a rotatable drum forming one wall of vsaid box-like structure to evenly distribute the matter over the surface of the belt, said drum having annular grooves adjacent its ends, and means on the box-like structure iltting within said grooves to form a fluidtight joint with the drum.

2. In combination witha belt for conveying fluid matter to be dried, means for delivering such matter to the belt, abox-like structure overlying the belt at the point of delivery of matter thereto, a rotatable drum forming one wall of said boxlike structure to evenly distribute the matter over the surface of the belt, said drum having annular grooves adjacent its ends, and means on the boxlike structure tting within said grooves to form a fluid-tight joint with the drum.

3. In combination, a belt for conveying iluid matter to be dried, means for delivering said matterto the belt, a rotatable roller spaced from the 1 claim,

belt and positioned adjacent the delivery means for causing even distribution of the matter over the surface of the belt, and means for adjusting the spacing between the roller and the belt.

CHARLES MCLEAN.

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