US2441021A - Vacuum chamber loading means - Google Patents

Description

-exit end of the chamber.

Patented Mn! 4 1 I 2.441.021 vacuum CHAMBER LOADING MEANS Arnold H. Heineman; Chicago, Ill.,' assignor, by mesne assignments, to Guardite Corporation, Wilmington, Del., a corporation of Delaware Application February 2, 1944, Serial No. 520,773

8 Claims. 1

This invention relates to a vacuum chamber and more particularly to a vacuum drying chamber in which a plurality of spaced rows of conveyors are employed.

. In the preferred form the invention, finely divided material for drying is conveyed in trays along conveyors in vertically spaced rows.

The invention is illustrated in the drawings in which Fig. 1 is a plan view of the drier system; Fig. 2 is a side elevation; Fig. 3a is a sectional side elevation of the cooking chamber in the drier; Fig. 3b is a similar view of the receiving chamber Fig. 3c is a similar view or the discharge chamber; Fig. 4a is a plan view partly in section of the top of the cooking chamber; Fig. 4b is a similar view of the receiving chamber; Fig. 4c is a similar view of the discharge chamber; Fig. 5 is a section taken along the line 5 in Fig. 3a; and Fig. 6 is a sectional view taken along the line t@ in Fig. do.

As shown in the drawings, the invention is applied to a drying system it comprising a vacuum chamber H. The vacuum chamber l I is made up of a cooking chamber i2, and an adjacent receiving chamber it separated therefrom by a door it, which may be moved sidewardly into the space it as shown in- Fig. l- The drier includes an entrance ii and an exit M which are provided with suitable doors. The structure of the entrance and exit closures are described in my co-pending applications Serial Nos. 501,398 and 501,399, filed September 6, 1943, now Patents Nos. 2,370,660 and 2,373,891, respectively, Suitable means for evacuation it are provided with a draw-on preferably from the central upper portion of the vacuum chamber.

Supporting means it are provided within the chamber for maintaining a series of conveyors 2| in spaced vertical rows. The series of trays 25 are mounted upon the conveyors and conveyed by any suitable system from the entrance to the convey sy tem will be described later in more detail.

Means it for heating the material within the vacimm chher by radiant heat is provided. A

preferred heating system is described in more detail in co-pending application Serial No. 500,9i9, ed ieptember 2, 1943, now abandoned. It is preferred t each row of material be provided with heating means above and below it and in close proty thereto. Accordingly, the heating means is connected to a header pipe 26a irom which radiation pipes 2th lead across the chamber, with apipe 20b being positioned above and ow e a The material which is ordinarily a food product in sliced, diced, or other finely divided form, is carried within the trays 25. It is placed in such trays individually outside of the drying chamber and the trays are then suspended in a buggy 30 as shown in Figures 1 and 2. The buggy is provided with a series of supports it mounted in vertically spaced rows corresponding to the spacing of the conveyor rows 2!. Each tray is wide enough to span the width of the drying chamber, as shown in Figure 5. In a typical buggy there will be six rows 0! supports, each containing eight trays, or a total of 48 trays of material. The buggy 30 is adapted to be suspended from a trolley 01 mounted on a track ll. The buggy is mounted on a series 01 wheels 36 which wheels also serve to guide the buggy on tracks '34 and 32 and the extension track 35 in the receiving chamber. It is preferred to employ at least two buggies, one of which may be unloading within the drying chamber while the other is loading. This may be accomplished by providing one or more spurs 40 in which one buggy may be sidetracked to permit entrance of the other into the drying chamber.

Assuming that the buggy 30 has been loaded on track32 with 48 trays of material for drying, it is then pushed on the track 32 until it is on the trolley 31 and the trolley is then pushed on produce the desired cooking temperature for the desired length oi time, The door it may then be opened, allowing the steam to escape into the vacuum chamber, or the cooking chamber may itself be evacuated'before opening the door. A vacuum pipe 42 is shown and may be connected to any suitable form of evacuating equipment.

The position of the buggy within the cooking chamber is indicated in Figures 3a and 5. After the buggy 80 has been moved into the chamber the proper distance, the lever 45 is moved inwardly toward the buggy to lock the pin 40 in the opening 41 in the beam of the traveler ll.

- This is accomplished by mounting the lever 45 substantially at right angles to the front of the cooking chamber i2 with extensions leading to the pins it and mounted in a cam-like arrangewhich roll in the channels it ment so that when the lever is pushed inwardly toward the buggy the gagement with the openings 47.

' It will be observed that the cooking chamber also forms a lock chamber.

It is obvious that means must be provided for carrying the trays from the buggy onto the conveyor system. This is accomplished by a double cantilever apparatus in which the conveyor itself provides one cantilever and the buggy provides the second cantilever. In this way the buggy may be run into the receiving chamber I 3 and at the same time the conveyor may be extended as a cantilever into the same chamber to pick up the trays from the buggy.

The carriage trated in Figures 3a. 3b, 4a, 4b and 5. As is there shown, 60 is a drive shaft carrying a pair of sprockets 5| and 52 and a pair of chains 53 and 54 thereon. These chains extend to the idlers Bi and 62 on the shaft 55 which is mounted on the framework of the apparatus and extends across it. Each of the chains 53 and 54 is secured by 9. lug 63 to the floating frame or carriage 56.

In this way movement of the chains 53 and 54 moves the carriage correspondingly.

The floating frame or carriage 58 is mounted on another chain 65 by the sprocket wheels 66 and 51, as shown in Figure 3a, and is carried by the lug 64 in channel 72 attached to the ceiling of the structure. The under portion of the chain 65 is secured by the lugs 13 to the traveler 48 which is free to move with respect to the carriage 56.

The floating frame is mounted on the rollers secured to the celling of the drier. The front end of the channel, as shown in Figure 5, is boxed in at 12 to limit forward movement of the frame.

The movement of the buggy into and out of the drier is accomplished by the chains 53 and 54. As-

suming that the buggy has entered the drier and 56 by the pins 46 and the doors closed, the buggy remains in the cooking chamber with the door I 4 to the receiving chamber closed and cooking is carried out as will be hereinafter described. After this operation is complete, the door i4 is opened and the shaft 60 driven to drive the chains 53 and 54. As these chains turn, by a counterclockwise motion of the shaft, as seen in Figure 3a, the lugs 63 secured to the carriage 55 necessarily draw that carriage from left to right, as viewed in Figure 3a. At the same time the chain 65 carried on the frame and secured by the lugs 64 to the ceiling of the drier, moves in the opposite direction relative to the frame. This causes the lower half of the chain 65 to move forward and carries the traveler 49 with it at a speed which is twice that of the chalns s: and 54. The result is that when the end of the carriage 56 has reached its most advanced position, as shown in Figure 8b, the traveler 49 has carried the buggy completely into the receiving chamber 13 so that the buggy has moved twice as far as the carriage 55. In this operation, the advanced end of the trolley which extends into the receiving chamber I3 is cantilevered from its position in the channels H. while the buggy is riding on the I- beam which is an extension of the I-beam 34 in the cooking chamber but is separated therefrom to permit closing of the door between the two chambers.

The movement of the carriage 58, and, therefore, of, the buggy. is limited by any suitable limit switch mechanism. A satisfactory system is indiplns are pulled into en- 4 be used to contact any suitable switch, not shown,

system 50 for the buggy ls illushas been clamped to the floating frame or trolley 4 j cated in Figures 3a and do by the rack 15, driven by the-pinions I8 on the shaft 60. The rack may at each end of its movement. This switch should be electrically connected to the drive motor for drive shaft 60.

The conveyor system illustrated comprises a verticalseries of conveyor tracks extending from the discharge end of the drier into the receiving chamber. These are best shown in Figures 4b and 6. The tracks 80 are mounted in six vertical rows and are secured to the vertical supports 8! and the cross members vB2. In Figures 30 and 6 trays 25 are illustrated in position on the tracks. These trays comprise a foraminous bottom 25a and solid side walls 250 having dependent extensions 250. The trays are also provided with longitudinal extensions 25d which act as carriers for the trays and rest upon the guides 83, as shown in Figure 6.

The tracks 80 are provided at spaced intervals with dogs 84 which are pivotaliy mounted in the seats 85 and are so constructed as to assume the position shown in Figure 3b by the force of gravity. In this position, the dogs permit motion of the trays from left to right of the figure; that is, in a forward direction, but do not permit rearward motion of the trays. The extensions 250 on the side walls of the trays are ufiiciently long so that they will catch upon the steep forward side 84a of the dogs and that the dogs will not touch the screen bottom of the trays 25a.

The trays are caused to progress through the drier by the conveyor tracks which are likewise provided with a series of dogs 84 of the same type as those in the fixed tracks 80. It will be understood that the spacing of the dogs is sufiicient to permit one tray to rest between them, as shown in Figure 3c. The guides 83 extend from thefront of the receiving chamber I 3 to the rear of the drier and into the discharge chamber IS. The fixed tracks 80 extend from the front of the receiving chamber to the rear of the drier and into the discharge chamber. The conveyor tracks 90 terminate approximately two trays short of the discharge end of the drier, and the front end thereof is cantilevered into the receiving chamber 50 as to pick up the last of the trays carried by the buggy. The posts 14, as shown in Figure 3b, serve as a support for the cantilevering of the tracks 90, 80 and the guides 83. It will be noted in Figure 3b that the horizontal supporting rows 31 are maintained in this relationship by the posts 31a and 31b and are cantilevered at their forward ends. The posts 3|b can, therefore, go into the receiving chamber up to the posts 14. Furthermore, the posts 3 l b and Me of the buggy are at the extreme outside and move in the channels I I3 and H4 at the outside of the first half of the receiving chamber. In this way the entire guide and conveyor mechanism is cantilevered into the first half of the receiving chamber and the buggy mechanism is cantilevered into the second half of the receiving chamber. Intermediate cross members H5 serve to hold the guides 83 and the stationary tracks 80 in lateral spaced relationship and the movable tracks 90 are held in similar relationship by cross members H6. The tracks 80,

supported by the cross members 82, and these same members, support the tracks 90 except where they are cantilevered into the receiving chamber. The tracks 90 are maintained in fixed relationship to each other by the cross members 9|.

At the discharge end of the chamber a third set of tracks 96 is provided having a single dog It on each track.

Thetracks 90 are moved in reciprocating motion bythe motor I provided with the reversing switches IOI and I02. These switches limit the motion of the conveyors 90 in each direction to a distance just greater than the width of one tray. It is preferred that motion of the trays be reasonably rapid but that the trays rest in each position a suitable itme as, for example, from 1 to 3 minutes. Any suitable timing device is, therefore, employed so that the motor I00 is inoperative during this time. The motor I00 is provided with a sprocket wheel I03 which drives the larger sprocket wheel I04 through the chain I05, and this in turn drives the gear box I08, and this in turn drives the shafts I01 and I08. Each of these shafts carries a sprocket wheel IIO which drives the sprocket wheel III through the chain 2. This chain H2 is secured to the lug I which is in turn secured to the beam I2I upon which the ends of the movable conveyor 90 are mounted. Reciprocation of the wheel III, therefore, causes the conveyors 90 to move alternately rearwardlyand forwardly adistance which is slightly more than the width of one tray. This may best be illustrated in Figure 3c, in which the dogs 84b represent those carried by the conveyor 90, and the dogs 84c represent those carried by the fixed tracks 80. The motion of the conveyor toward the rear of the drier causes the dogs 84b to carry the trays beyond the dogs 840. The conveyor then 6 1 foot in width. The material isloaded on the screen bottom to a depth of not much more than A inch. The loaded-buggy is moved onto the trolley 31 across to the tracks 34 and then into the cooking chamber I3. the door 4| having been opened to receive it. The door I is then closed. At this time the door I4 to the receiving chamber is closed. The material is cooked in the cocking chamber by first evacuating it to remove air and then introducing steam to produce cooking or blanching for a short period. A suitable temperat re is 212 F. at 0 lb. steam pressure, which is maintained for about 2 minutes. This time and temperature of course varies with the material being'treated and the particular figures given are for a typical product such as potatoes in diced orm.

After the cooking operation has been completed the doors I4 are opened and the buggy is driven into the receiving chamber by the dual operation of the floating frame 58 and the carrier frame 49. At the conclusion of this operation, the front moves toward the front of the drier and any tendwheels I which drive chains I3! and the wheels I32. The chains I3I are attachedby a lug I33 to the beams I34 which in turn are secured to the cross members I35 which maintain the discharge tracks 95 in spaced relationship. It will be noted that the wheels I32 and I30 are larger than the wheels I I0 and I I I, so that, on reciprocation of the motor, the chain I3I is driven farther in each direction than is the chain I I2. This is important because the trays, upon discharge, must be forced to clear the necessary opening for the discharge lock and, therefore, cannot be maintained in con- I tact at this point.

The discharge lock is described in detail in my co-pending application Serial No. 501,399, filed end of the bug y is cantilevered over the conveying system proper, whereas the front end of the conveying system is cantilevered under the rear end of the bug y. The buggy is then withdrawn, the dogs at holding the trays in position upon the conveying system. The doors I4 are then closed and the drying operation proper commences. During all of this time the drying chamber is maintained at a suitably low pressure. which is normally below 100 mm. and suitably is below 60 mm. Drying is accomplished mainly by retaining heat which may be produced by steam coils suitably disposed between the trays. A specific disposition of such coils is disclosed in my co-pending application Serial No. 500,949, filed September 2, 1943, and these are not disclosed in detail in the present application because their presence would unduly complicate a description of the conveying system.

Drying is promoted in addition by the liberal use of superheated steam which is preferably in- September 6, 1943. In brief, it consists, as shown in Figure 4c, of the chamber I8 closed by two sets of doors I36 and I31. These doors are never opened at the same time during operation of the device. Before discharge of a. series of trays from the system, both of the doors are closed and the discharge chamber is evacuated to the pressure of the system. The doors I36 are then opened and at that time conveyors 90 and 35 operate and the conveyors 95 press one tray in each row into the discharge chamber. The doors I36 then close and the doors I31 are opened and the trays removed from the discharge chamber. The doors I31 are again closed, the system evacuated, and the process repeated. It is obviously desirable, when employing such'a system, that the motion of the conveyor in the discharge direction be followed immediately by motion in the opposite direction, and that the necessary rest period ensue while the conveyors are in their retracted position.

In the operation of the entire system, the bug 30 is first loaded with 48 trays of material, each tray being approximately 5 feet across and about .troduced at both the receiving and discharging ends of the system and is removed from the center thereof by the vacuum line I9.

It will be understood of course that the entire system may be and preferably is controlled by automatic time control operated through accordinated master system. In this way the only manual operations are the loading of the trays at the beginning and the removal of the trays from the discharge end. Both of these operations may be made mechanical if desired.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitatitons should be understood therefrom.

What I claim as new,"and desire to secure by ber, a. buggy mounted for movement along a path extending from the lock chamber into the vacuum chamber, a traveler adapted to drive the buggy along said path and carried by the car-.

riage, endless chain means on the carriage secured to a fixed point and to the traveler, and second endless means for driving the carriage.

2. In a drying system including a vacuum chamber: a lock chamber adjacent the vacuum chamber, a'carriage mounted within the lock chamber. a buggy mounted for movement alon a pathentending from the lock chamber into the vacuum chamber, a'traveler adapted to drive the buggy and carried by the carriage-,endleas chain means on the carriage secured to a fixed point and to the traveler, and-second endless means for driving the carriage and the buggy so constructed and arranged thatupon movement of the carriage the buggy is advanced completely outside of the lock chamber and into the vacuum chamber while retaining-at least a portion of the carriase within the lock chamber.

3. Apparatus as set forth in claim 2, in which the vacuum chamber includes a conveying system having a plurality of conveying tiers adapted to convey the material to be dried, with the buggy having a corresponding plurality of complementarily spaced loading tiers, and the buggy and the traveler of the conveying means are adapted for interlock over substantially the entire length oi the buggy when the buggy is advanced into the vacuum chamber.

4. In a drying system including a vacuum chamber: a lock chamber adjacent the vacuum chamber, a carriage mounted 'within the lock chamber, a buggy mounted for movement along.

a path extending from the lock chamber into the vacuum chamber and including a plurality of loading tiers and vertical posts holding the tiers in spaced relationship with at least substantial parts of the forward portions of the tiers being vertically unconnected to provide a cantilever structure, a traveler adapted to drive the buggy and carried by the carriage, endless flexible means on the carriage secured to a fixed point and to the traveler, and second endless flexible means for driving the carriage and the buggy so constructed and arranged that upon movement of the carriage the buggy is advanced completely outside of the lock chamber and into the vacuum chamber while retaining'at least a portion of the carriage within the lock chamber.

5. In a'vaclium drier, a vacuum chamber provided with an entrance and an exit, a plurality of separate drying zones in vertically spaced relationship to each other formed by spaced heating elements within the vacuum chamber extending longitudinally through amajor portion of it, loading means sub-divided into loading tiers forming loading zones specially corresponding with the drying zones and adapted to hold at least one container in each such zone, conveyor means supported i each drying zone within the drier, means for guiding the loading means into the drier, said conveyor means being cantilevered 6. In a vacuum drier, a vacuum chamber provided with an entrance and an exit, a plurality of separate drying zones in vertically spaced-relationship to each other formed by spaced heating elements within the vacuum chamber extendin longitudinally through a maiorportion of it.-

loading means sub-divided into loading tiers forming loading zones specially corresponding with the drying zones and adapted to hold at least one containerin each such zone conveyor means supported-in each drying zone within the drier, said conveyor means including gravity actuated stop members permitting motion of said containers in a forward direction only, and means for guiding the loading meansinto the drier, said conveyor means being cantilevered at its receiva Number at its receiving end to extend into each of the movable trays adapted to move upon both guides.

in each zone simultaneously. vided in the chamber for rial to be dried.

said trays being procontaining the mateing and to..extend.:-into each of the plurality of.

loading zones.

7. Apparatus as set forth in claim 6 including independent foraminous bottomed containers carried by the conveyor means and provided with side wall extensions depending below the-. foraminous bottom and adapted to contact the stop members 8. Apparatus as set forth in claim 6 including independent foraminous bottomed containers carried by the conveyor meanaand provided with side wall extensions depending below the foreminous bottom andadapted to contact the stop members, theamount of contact being less than the width of the side wall extensions.

ARNOLD H. HEINEMAN.

assurances crrnn Um'mn "sra'ras PATENTS I Name. Date 720,669 1 Chopin Feb. 17, 1903 888,257 Passburg May 19, 1908 1,275,547 Forrest Aug. 13, 1916 1,417,528 Irish et a1, May 30, 1922 1,449,659 Dworzak Mar. 27, 1923 1,454,675 Gantvoort; May 8, 1923 1,903,102 Farley Mar. 28, 1933 1,949,917 Muench Mar. 6, 1934 959,662 Ellis May 22, 1934 2,021,257 Kosman Nov. 19, 1935 2,098,154 Mauch Nov. 2, 1937 2,127,278 Welsh Aug. 16, 1938 2,165,641 Mattox July 11, 1939 3.321.253 Schellentrager June 8, 1943 2,376,457 Skoog May 22, 1945 FOREIGN PATENTS Number Country Date Great Britain 1907