US2795861A

US2795861A - Apparatus for drying coated sheet stock

Info

Publication number: US2795861A
Application number: US409681A
Authority: US
Inventors: James A Black
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-02-11
Filing date: 1954-02-11
Publication date: 1957-06-18
Anticipated expiration: 1974-06-18

Description

June 18, 1957 J. A. BLACK APPARATUS FOR DRYING COATEDSHEET STOCK Filed Feb. 11, 19 4 R m m V W.

O N Jame- 41.310 51 ATTORNEY June 18, 1957 J. A. BLACK APPARATUS FOR DRYING COATED SHEET STOCK HW llllll ll ATTORNEY 8 Sheets-Sheet s Na .VV N m 0% Wal -LE3 F:

. qwmwmwl i I ll Im I QWI WIMH Wr-IHI v mmu lEFM Filed Feb. 11 1954 June 18, 1957 J. A. BLACK 2,795,861

APPARATUS FOR DRYING CQATED SHEET STOCK Filed Feb. 11,

8 Sheets-Sheet 4 IN VENTOR James A. Black:

ATTORNEY June 18, 1957 J. A. BLACK 2,795,851

APPARATUS FOR DRYINGCOATED SHEET STOCK Filed Feb. 11, 1954 8 Sheets-Sheet 5 lllll Hi INVENTOR 757-1. 1.02 l

60 I63 145 J l 149 75 F .9 72 BY flmgazdzme 76 77 ATTORNEY June 18, 1957 J. A. BLACK 2,795,851

APPARATUS FOR DRYING COATED SHEET STOCK Filed Feb. 11, 1954 8 Sheets-Sheet 6 'IIIIIIIIIIIIIIIIIIIIIIIIIIIIIII llllhl filhmwul INVENTOR JilznesAuBlacli 46 i i WWW- ATTORNEY June 18, 1957 J. A. BLACK APPARATUS FOR DRYING CQATED SHEET STOCK 8 Sheets-Sheet 8 Filed Feb. 11, 1954 OOH- mm M bu Jilmes A. .Blacli ATTORNEY Unitd States Patent APPARATUS FOR DRYING COATED SHEET STOCK James A. Black, Grand Rapids, Mich.

Application February 11, 1954, Serial No. 409,681

8 Claims. (Cl. 34-150) The present invention relates to apparatus for drying coated sheet stock and more particularly to apparatus for drying flexible sheet stock such as paper which has been coated with paint or ink by the process known as silk screen stencil printing. a

In the process of silk screening decalcomanias, signs and other coated sheet stock, the coating materials used are of necessity relatively tacky and therefore slow drying. It is important, therefore, that the coated sheets be kept separate from each other while drying so that when they are finally piled in stacks they will not stick together. it is also important for reasons of space economy that the separate coated sheets be dried quickly and for this reason they are sometimes dried in a heated region or oven. However this last procedure may result in buckling and even shrinking of the sheets so that subsequent applications of coating material (when the sheets are multi-coated) cannot be applied in perfect registry with prior coatings. I have discovered that these conditions prevail partly because of the quick drying of the sheets but more particularly because the dried sheets are not permitted to return to their original, normal room temperature and humidity before piling them up or running them for a subsequent coating.

The primary objects of this invention are therefore to provide a method and apparatus whereby the sheets after coating with one material are quickly dried and are subsequently permitted to return to their normal temperature and humidity prior to being stacked one sheet upon another; and more particularly to provide a machine or apparatus which operates automatically to achieve the above desirable ends; and further to provide a machine wherein heat and humidity may be controlled so that the drying conditions can be adjusted to suit the qualities of the stock being coated and also the qualities of the coating materials used.

An illustrative embodiment of the invention is shown in the accompanying drawings, wherein;

Figure 1 is a side elevational view, somewhat diagrammatic, of the machine or apparatus of the present ht Figure 2 is a top plan view of the same;

Figure 3 is an enlarged fragmentary vertical sectional view of the machine, the general plane of section being indicated by lines- 3-3 of Figures 2 and and detail planes of section beingindieated by lines 33 of Figures 4 and 6; i l I Figure 4v is a fragmentary top plan view of certain parts of the machine;

g 5 is a ho i ontal sectional e o e machin talgen on lines 55 of Figures 1, 3, 6, and 14;

F u 6 is a a g d agment ry ie of he le an n the m n h wn Partl hi end el vat on and partly in vertical; section t;a ken on lines five-r6 of Figures 1, 5, 7 and 9;

Figure 7 is a fragmentary vertical sectional: view of parts oi the same taken on line ll-m7 of Figure 6;

ice

Figure 8 is a fragmentary vertical sectional view of parts of the same taken on line 8--8 of Figure 6; Figure 9 is a fragmentary vertical sectional view of parts of the same taken on line 9-9 of Figure 6;

Figure 10 is a fragmentary vertical sectional view of parts of the same taken on line 1010 of Figure 6;

Figure 11 is an enlarged fragmentary top plan viewof a sheet-carrying rack as it appears when traversing the table surface of the machine, and parts adjacent thereto;

Figure 12 is a fragmentary vertical sectional view of parts of the same taken on line 1212 of Figure 11;

Figure 13 is a fragmentary vertical sectional view of other parts of the same taken on line 13--13 of Figure 11;

Figure 14 is a fragmentary right hand end elevational view of the machine; and

Figure 15 is a fragmentary vertical sectional view of said right hand end of the machine taken on line 1515 of Figure 14.

Referring now in detail to these drawings, the automatic machine there shown for drying coated sheet stock is built upon a base frame of generally rectangular parallelpiped form constructed of angle bars all secured together as shown by means of rivets, bolts or the like. Mounted on top of this lower base frame 20. is a sheet metal superstructure generally designated 21 which has a horizontally elongated upper oven compartment 22 extending from the left or receiving end of the machine to a point near the right or discharge end of the machine. The right hand end of the sheet metal superstructure 21 is vertically elongated to form a stack 23 which is divided by an upstanding sheet metal partition 24 into an air inlet duct 25 and an air outlet duct 26 both of which communicate with the room atmosphere at their upper ends.

A blower 27 driven by an electric motor 28 is mounted near the upper end of the stack 23 (see Figure 1) and is interposed between the upper and lower portions of the air inlet duct 25 for circulating air through the duct 25 and the horizontally elongated upper oven compartment 22, thence through diagonally extending

side ducts

29 and 30 at opposite sides of the machine, thence through a lower oven compartment 31 disposed beneath the upper oven compartment 22 and extending from the left hand or receiving end of the machine to a point near the right hand end of the machine, whence the circulated air is exhausted through a vent 32 (see Figures 3 and 8) whose function is hereinafter more particularly described and'into the vertical air outlet duct 26, all as indicated by the air circulation arrows in Figures 1, 3, 5, 6, l4 and 15.

The oven of the machine is constituted by the upper oven compartment 22 and the lower oven compartment 31,the oven being divided thus by a horizontal table elet em 33-, secured to the framework 20 of the machine and ex nding from; a. poin near. the left hand or receiving and of th m hine to, a, point near the right hand or dis har e and of the a h ne. Mo n ed; on ap Sides of th -e ram mat the. t p f the frame, are t. of vert c l y ex ending: thr a ed columns or Posts 3 cm hi h. a e ve ti ally adi stabl-y hounteda Pai o ec c h at ng p at 35 y means of: nuts .6 hread d '0 he PQ I -4 which pp rt frames: 37 fQ T'ih heating pla e 35 at ver ica -1y ec d positions. Lugs- 8cm the upport: f am s 37 ext n hrough vert c l slots. 32 in the machinessheet metal'superstructure 21 so that the e e a on f the. heating plat s above the. t b 33. an be adjus ed m the ex er or. of he machine. E s r d Wir s 40 x en r m. t e hea insp ates35 through the ceiling ofthe ovens uppercompartment 22. In Figures 3; and 8 the heating platesc35 are shown in dotted lines intheir extreme uppermost position and in solid lines in an intermediate position of elevation above thetable 33.

A drive shaft 41 has its ends journalled on opposite sides of the machines frame 20 near the upper right or receiving end of the machines oven. This drive shaft 41 extends beyond the machines frame 20 a slight distance to the left as viewed in Figure 6 and is provided at that end with a sprocket 42 over which passes a chain 43 which is connected to a suitable source of power (not shown) for driving this drive shaft and other parts of the machine which are mechanically connected thereto as hereinafter described. This drive shaft 41 is driven in a clockwise direction as viewed in Figures 3 and 7 through 10.

A shaft 44 has its ends journalled on opposite sides of the machines frame 20 near the upper left or discharge end of the machines oven. The drive shaft 41 and shaft 44 have mounted thereon aligned pairs of

sprocket wheels

45, 46 on

shaft

41 and 47, 48 on shaft 44. Sprocket chains 49, 50 pass over these aligned pairs of sprocket wheels respectively and are driven by the drive shaft 41, the upper sections of the chains 49, 50 passing in unison through the upper oven compartment 22 and constituting a conveyor therethrough hereinafter referred to as the upper conveyor.

A shaft 51 has its opposite ends journalled on opposite sides of the machines frame 20 below the drive shaft 41 near the receiving end of the machines oven, and a shaft 52 is similarly journalled below shaft 44 near the discharge end of the oven. These

shafts

51 and 52 have aligned pairs of

sprocket wheels

53, 54 on shaft 51 and 55, 56 on shaft 52.

Sprocket chains

57 and 58 pass over these aligned pairs of sprocket wheels respectively, the lower sections of these

chains

57, 58 constituting a lower conveyor beneath the oven, which lower conveyor travels in a direction opposite to that of the upper con veyor.

At one side of the machine (the near side as viewed in Figures 1, and 7, and the right hand side as viewed in Figure 6) and at the receiving end of the oven, is mounted a gear box 59 having a cover 60. The chain of gears within this gear box 59 includes a small driving gear 61 on the drive shaft 41, a large idler gear 62 on an idler shaft 63 which gear 62 meshes with the gear 61, a small idler gear 64 also on the idler shaft 63, and a large driven gear 65 on shaft 51 meshing with the idler gear 64. The arrangement and the gear ratios are such that shaft 51 and the lower conveyor chains 57,- 58 are driven by the drive shaft 41 in an opposite direction and at a much slower speed than the drive shaft 41 and the upper conveyor chains 49, 50.

Upper tracks

66, 67 are secured to opposite sides of the machines frame 20 slightly above the table 33, and

lower tracks

68, 69 are secured to opposite sides of the machines frame spacedly beneath the ovens lower compartment 31. Curved track sections 70, 71 connect the upper tracks with the lower tracks respectively at the receiving end of the machines oven, and similar

curved tracks

72, 73 connect the upper tracks with the lower tracks respectively at the right or discharge end of the machines oven.

Sheet-carrying racks 74, the opposite end details'of which are best shown in Figures 11-13, are provided for carrying the coated sheets through the machine. Each rack comprises a rack shaft 75 on the opposite ends of which are turnably mounted

rollers

76, 77 which travel in the continuous tracks at opposite sides of the machine. A guide arm 78 is rotatably mounted on the rack shaft 75 near one end thereof (the far end as viewed in Figure 3) and is provided with a roller 79 the function of which is hereinafter described. A block 80 is also rotatably 'mounted on the rack shaft 75 near its opposite end (the near end as viewed in Figure 3). An angle-bar gripper bar 81 extending from side to side of the machine has one of its ends fixedly secured to the guide arm 78 by means of a bracket 82 (see Figures 11 and 12), which bracket 82 is fastened to the guide arm 78 by means of a screw 83 and to the gripper bar 81 by means of another 4 screw 84; and the gripper bar has the other of its ends secured to the block by means of a screw 85.

Each sheet-carrying rack 74 also has a trip arm 86 fixedly secured by means of a set screw 87 on the near end of the rack shaft 75, adjacent block 80, and this trip arm 86 has a roller 88 turnably mounted on its outer end the purpose of which roller is hereinafter described. Each sheet-carrying rack 74 is also provided with a plurality of spaced gripper fingers 89 secured thereon which are normally urged toward contact with the gripper bar by means of coil springs 90 but which, when the rack shaft 75 is turned relative to the gripper bar 81, are moved by pins 90.0n the rack shaft 75 out of engagement with the gripper bar.

The loaded sheet-carrying racks 74 are moved across the

upper tracks

66, 67 from left to right as viewed in Figure 3 by means of the upper conveyor chains 49, 50 which are provided with lugs 92, 93 (see Figure 11) which engage the rack shafts 75 during their travel from the receiving end of the oven to the discharge end of the oven. Transfer means are provided for transferring the racks from the upper conveyor chains 49, 50 to the lower conveyor chains 56, 57 at the discharge end of the oven. These transfer means comprise a turnover lever 94 pivotally mounted on an upright post 95 secured to the machines frame 20, which lever has a lower, normally horizontal arm 96 and an arcuate upper arm 97 and which is urged to its normal position shown in full lines in Figure 8 by a tension spring 98, and a pair of transfer segments 99 mounted on the opposite ends of a shaft 100 which is journalled in spaced support arms 101 secured to the machines frame 20 and extending transversely of the machine in parallellism with

shafts

44 and 52. This mechanism, the operation of which is hereinafter more fully described, transfers the racks 74 from the upper conveyor to the

lower conveyor chains

57, 58 which are provided with

lugs

102, 103 respectively for engaging the rack shafts 75 and thus carrying the racks from right to left on the

lower tracks

68, 69 as viewed in Figure 3, beneath the machines oven.

Transfer means are also provided at the left hand or receiving end of the machine for transferring the racks 74 from the

lower conveyor chains

57, 58 to the upper conveyor chains 49, 50. These transfer means comprise a pair of lifting arms 104, 105 and a pair of cooperating supporting

levers

106, 107 at opposite sides of the machine (see Figures 6, 7 and 8). The lifting arms 104, 105 are provided with slots 108 (see Figure 8) into which extend pins 109 on the machines frame 20 for slidingly supporting the lifting arms in the rear. Forwardly of these connections, the lifting arms 104, 105 are pivotally connected to cranks 110, 111 mounted on

shafts

112, 113 journalled on the machines frame 20. Shaft 112 at the right hand side of the machine as viewed in Figure 6, extends into the gear box 59 and has a driven gear 114 (see Figure 7) which meshes with an idler gear 115 on an idler shaft 116 journalled in the gear box, and the idler gear 115 in turn meshes with a driving gear 117 mounted on the drive shaft 41. At the opposite side of the machine the shaft 113 to which lifting arm 105 is connected by crank 111, is provided with a driven gear 118 which meshes with an idler gear 119 on an idler shaft 120 journalled on the machines frame 20, and the idler gear 119 in turn meshes with a driving gear 121 on the drive shaft 41.

The supporting

levers

106, 107 are mounted on blocks 122 secured to the arcuate tracks 70, 71 at the receiving end of the machine and are normally maintained in their position shown in Figure 8 by means of tension springs 123 secured to the adjacent arcuate tracks and to these levers, in which position the supporting levers are adaptelg tosupport a sheet-carrying rack 74 by its rollers .76,

A camwheel 124 having a raised cam surface 125 is rotatably mounted on the'drive shaft 41 near the right hand side of the machine as viewed in Figure 6. (See also Figures 9 and 13.) This camwheel 124 is providedfor the purpose of tripping the trip arms 86 on the racks 74 at the receiving endof the machine as hereinafter more fully described. Although mounted for rotation on the drive shaft 41, the camwheel 124 rotates in a direction opposite to that of the drive shaft 41 as indicated by the arrows in Figure 9. As best seen in Figures 6 and 10, the camwheel 124 is driven by means of a sprocket chain 126 which passes over a sprocket wheel 127 on the camwheels hub 128 and over an idler sprocket wheel 129 mounted on a shaft 130 journalled in spaced supports 131, 132 depending from the machines frame 20. The chain 126 is driven by a sprocket wheel 133 on a shaft 134 also journalled in the depending supports 131, 132, and shaft 134 is driven by means of a sprocket chain 135 which passes around a sprocket wheel 136 on the shaft 134 and a sprocket wheel 137 on the drive shaft 41. It will be seen that the arrangement is such that the camwheel 124 is driven in a direction opposite to that of the drive shaft 41.

Operation Coated sheet stock is fed into the drying machine at the left hand or receiving end of the machine as viewed in Figures 1, 2, 3 and 5 of the drawings. As each sheetcarrying rack 74 moves upwardly in the curved track sections 70, 71, at which time the rack is empty, it is engaged by the lifting arms 104, 105 as illustrated in Figure 8 and is lifted past the supporting levers 106, 167. During this movement the

rollers

76, 77 on the rack 74 cam the levers out of the way as indicated by dotted lines in Figure 8. When the rollers have cleared the

levers

106, 107 these levers are returned to their solid line positions shown by

springs

123, 124, in which positions they support each rack 74 for a brief pause in its circuit of the machine. During this pause the raised surface 125 of camwheel 124 engages the trip arm 86 on the rack as shown in Figures 9 and 13, thus rotating the racks shaft 75 relative to the racks gripper bar 81 and turning the gripper fingers 89 away from the gripper bar, thus opening the rack so that a coated sheet 138 can be fed into it, either manually or by means of a sheett'eeding device.

When the raised surface 125 of camwheel 124 passes the trip arm 86 of the rack, the rack is closed by springs 90 so as to grip the coated sheet therein. When this occurs, a pair of

lugs

92, 93 on the upper conveyor chains 49, 50 pick up the rack 74 by its shaft 75 and move the rack and its coated sheet swiftly across the upper surface of the machines table 33 and through the oven from its left hand or receiving end to its right hand or discharge end, during which travel the coated sheet is quickly dried.

When the dried sheet 138 reaches the right hand or discharge end of the oven, it receives a blast of warm air from the vent 32 in the upper surface of the table 33. This air is forcefully moved by a blower 139 driven by motor 140 through pulley belt 141, from the ovens lower compartment 131 through chamber 142, through vent 32 and thence upwardly into the vertical air outlet duct 26 of the machines stack 23. The air is then discharged from duct 26 through its upper end, or it may be re-circulated through the oven either in whole or in part. Damper 143 may be manually set to control the amount of warm air re-circulated from duct 26 and the amount of fresh air taken in through the air inlet duct 25.

The blast of air which the dried coated sheet 138 receives from vent 32 tends to throw the sheet over to the right as indicated in Figures 3, 5, 14 and 15. At about this same time, the racks shaft 75 reaches the horizontal arm 96 of the turnover lever 94, and as the rack is driven past this lever by the upper conveyor chains the lever is rotated and its arcuate upper arm 97 engages the guide arm 78- on the rack and throws it over to the right thus rotating the entire rack in a clockwise direction. As soon as

lugs

92, 93 on the upper conveyor chains 49, 50 leave the rack 74 at this point, the rack is picked up by the radial edges 144 of the rotating transfer segments 99 and the rack is gently lowered thereby through the lower portions of the curved end tracks 72, 73. At this point the rack is picked up by a pair of

lugs

102, 103 on the

lower conveyor chains

57, 58 and is moved at slow speed from right to left on the straight

lower tracks

68, 69 beneath the oven. During this travel the rack is maintained in proper position with the dried sheet 138 depending vertically therefrom by means of a lower guide rail along which travels the roller 79 at the end of the racks guide arm 78. This slow travel of the sheet from right to left enables the sheet to return to normal room temperature and humidity.

When the rack 74 reaches a point near the left end of the

tracks

68, 69, its upwardly projecting trip arm 86 strikes an angular release bar 146 (see Figures 3 and 4) depending from a post 147' mounted on lower track 68. This contact momentarily rotates the racks shaft 75 relative to its gripper bar 81, thus opening the rack so that the dried sheet carried thereby is deposited in a depository therefor here shown as a tote box 148.

The rack then travels back to the receiving end of the machine to progress upwardly along the curved tracks 70, 71, and is maintained in proper position during such upward travel by travel of the rollers 79 on the racks guide arm 78 in a curved guideway 149 secured to the machine by means of posts 150 mounted on arms 151 on the machine. The racks circuit of the machine is then repeated as above described.

It will thus be seen that the invention provides a novel method and apparatus whereby coated. sheet stock may be quickly dried and thereafter slowly permitted to return to normal room temperature and humidity before stacking, and while but one specific embodiment of the invention has been herein shown and described, it will be understood that'numerous details may be altered or omitted without departing from the spirit of the invention as the same is defined by the following claims.

I claim:

1. A machine for drying coated sheet stock comprising: a frame; a horizontally elongated oven mounted on the frame in elevated position and having a receiving end and a discharge end; a horizontal table Within the oven; parallel horizontal upper tracks on opposite sides of the frame extending through the oven above the table;

parallel horizontal lower tracks on opposite sides of the frame beneath the oven; sheet-carrying racks movable in the tracks and provided with grippers movable to closed positions for gripping coated sheets and to open positions for releasing dried sheets; means for closing the grippers near the receiving end of the upper tracks to thereby grip coated sheets fed thereto; an upper conveyor inside the oven for moving the fil-led racks on the upper tracks across the upper surface of the table from the receiving end to the discharge end of the oven; a lower conveyor beneath the oven for moving the filled racks on the lower tracks from the discharge end of the oven to a depository near the receiving end of the oven; means near the discharge end of the oven for transferring the racks from the upper conveyor to the lower conveyor; means near the depository for opening the grippers thereby to deposit the dried sheets at the depository; and means near the receiving end of the oven for transferring the empty racks from the lower conveyor to the upper conveyor.

2. A machine for drying coated sheet stock comprising: an elevated, horizontally elongate oven having a receiving end and a discharge end; an upper conveyor inside the oven for moving coated sheets through the oven from the receiving to the discharge end thereof; a lower conveyor outside and beneath the oven for moving dried sheets from the discharge end of the oven to a depository; a. plurality of sheet carrying members for engaging coated sheets and engageable with said conveyors for movement of the sheets therewith; means for transferring said sheet carrying members from the upper to the lower conveyor adjacent the discharge end of the oven; and means for releasing the sheets from the carrying members on the lower conveyor at the depository.

3. A machine for drying coated sheet stock comprising: an elevated, horizontally elongate oven having a receiving end and a discharge end; an upper conveyor inside the oven for moving coated sheets through the oven from the receiving to the discharge end thereof; a lower conveyor outside and beneath the oven for moving dried sheets from the discharge end of the oven to a depository; a plurality of sheet carrying members for engaging coated sheets and engageable with said convcyors for movement of the sheets therewith; means for transferring said members from the upper to the lower conveyor adjacent the discharge end of the oven; means for releasing the sheets from the carrying members on the lower conveyor at the depository; and means for transferring said carrying elements from the lower to the upper conveyor adjacent the receiving end of said oven.

4. Amachine for drying coated sheet stock comprising: a frame; a horizontally elongated oven mounted on the frame in elevated position and having a receiving end and a discharge end; a horizontal table within the open; parallel horizontal upper tracks on opposite sides of the frame extending through the oven above the table; parallel horizontal lower tracks on opposite sides of the frame beneath the oven; sheet-carrying racks movable in the tracks and provided with grippers movable to closed positions for gripping coated sheets and to open positions for releasing dried sheets; means for closing the grippers near the receiving end of the upper tracks to thereby grip coated sheets fed thereto; an upper conveyor inside the oven for moving the filled racks on the upper tracks across the upper surface of the table from the receiving end to the discharge end of the oven; a lower conveyor beneath the oven for moving the filled racks on the lower tracks from the discharge end of the oven to a depository near the receiving end of the oven; means near the discharge end of the oven for transferring the racks from the upper conveyor to the lower conveyor; means near the depository for opening the grippers thereby to deposit the dried sheets at the depository.

5. A coated sheet drying machine according to claim 2 including a horizontal table disposed within said oven and extending substantially between the receiving and discharge ends thereof; said sheet carrying members being moved through said oven by said upper conveyor above said table whereby said sheets rest upon the table in substantially horizontal position as they are moved through the oven; and said sheet carrying members being carried by said lower conveyor in substantially depending relation therefrom whereby said sheets are carried in substantially vertical disposition thereby.

6. A coated sheet drying machine according to claim 3 including a horizontal table disposed within said oven and extending substantially between the receiving and discharge ends thereof; said sheet carrying members being moved through said oven by said upper conveyor above said table whereby said sheets rest upon the table in substantially horizontal position as they are moved through the oven; and said sheet carrying members being carried by said lower conveyor in substantially depending relation therefrom whereby said sheets are carried in substantially vertical disposition thereby.

7. A coated sheet drying machine according to claim 4 wherein said table is disposed just below said upper tracks whereby coated sheets rest upon the table in substantially horizontal position as they are moved through the oven; and said racks being suspended from the lower conveyor such that the sheets are disposed in depending substantially vertical disposition from the lower conveyor.

8. A coated sheet drying machine according to claim 1 wherein said table is disposed just below said upper tracks whereby coated sheets rest upon the table in substantially horizontal position as they are moved through the oven; and said racks being suspended from the lower conveyor such that the sheets are disposed in depending substantially vertical disposition from the lower conveyor.

References Cited in the file of this patent UNlTED STATES PATENTS 860,621 Taylor July 16, 1907 881,602 Marr Mar. 10, 1908 1,115,551 Lamey Nov. 3, 1914 1,194,647 Lipsius Aug. 15, 1916 1,446,947 Taliaferro Feb. 27, 1923 1,572,180 Buzza Feb. 9, 1926 1,660,901 Willsea Feb. 28, 1928 2,355,697 Belluche Aug. 15, 1944 2,359,825 Campbell Oct. 10, 1944 2,625,394 Brown Ian. 13, 1953