US2829372A - Apparatus for stitching sheet material - Google Patents

Description

6 Sheets--Shee' 1 J. LOJ EWSKI APPARATUS FOR STITCHING SHEET MATERIAL April s, 1958 Filed Jan. 4. 1955 INVENTOR.

ATTORNEYS.

| JOSEPH Lwsm April 8, 1958 J. LoJEwsKl 2,829,372

APPARATUS FOR STITCHTNG SHEET MATERIAL Filed Jan. 4, 1955 I 6 Sheets-5h99?I 2 I N V EN TOR. JOSEPH Loan-:wma

ATTORNEYS.

April 8, 1958 Filed Jan. `4, 1955 J. LOJEWSKI APPARATUS FOR SITITCHING SHEET MATERIAL 6 Sheets-SheefI 3 F/G 3 im nu "13g" u u n Il u L I um LII

1N VEN TOR. JOSEPH kJw/m April 8, 1958 .1. LoJEWsKl 2,829,372

APPARATUS-Foa STITCHING SHI-:ET MATERIAL Filed Jan. 4, 1955 6 Sheets-Sheet 4 IN VEN TOR. a LoJEwsKx lM'To RNEYS.

April 8, 1958 .J. LJEwsKl 2,329,372

APPARATUS FOR STITCI-IING SHEET MATERIAL Filed Jan. 4, 1955 6 Sheets-Sheet 5 I INVENTOR. JOSEPH Loaewsw ATTORNEYS.

April s, 1958 J. LOJEWSKI APPARATUS FOR STITCHING SHEET MATERIAL Filed Jan. 4, 1955 6 Sheets-Sheet 6 0 LA j/ 15 51 /'B 15% C( '14k` A? sa 11.

I y 9 v 'I IJr INVEN TOR. JQSEPH Lo Jaws m ATTORNEYS.

United States Patent O APPARATUS FOR STITCHING SHEET MATERIAL Joseph Lojewski, Cleveland, Ohio Application January 4, 1955, Serial No. 479,835 7 claims.' (cl. 1-1o6) The present invention relates to the stitching of sheet material and more particularly to the automatic multiple stitching or stapling of paper sheets by means of a single stitcher head.

ln the production of magazines,pamphlets and other printed matter consisting of a plurality of paper sheets or pages, it is customary to secure such pages in assembled relationship by suitable fastening or adhesive means, or a combination of such means. Although thread stitching or sewing, as well as gluing are used to some extent, particularly in the production of permanent library pieces, such fastening methods are generally used in combination with stapling. By far the majority of printed or published matter is of a temporary or expendable character and stapling is generally used exclusively in assembling such matter.

There are broadly two general types of stapling or stitcher equipment. In the automatic type, the sheet material is conveyed to a position Where it can be engaged by two to five stapling heads which operate simultaneously on the material. The heads are adjustably mounted so that they can be spaced from each other to give the desired stapling spacing. The stapling heads are automatically actuated when the material is properly positioned.

There is also a semi-automatic type in which only a single stapling head is used. The material to be stitched is positioned manually, and the stapling head, though power driven, is controlled manually. The material can be moved manually and progressively to each of several desired positions under the single stapling head and thereby a plurality of stitches are obtained.

The automatic, multiple head stitching machine is utilized for high production of large quantities. The semiautomatic, single head stitching machine is used for small lots or for large production quantities which cannot be run on the automatic machine. It is well known that the manually controlled, semi-automatic operation is slower and considerably more costly in labor than the fully automatic operation. However, there are several valid reasons for the use of the semi-automatic operation, including the following:

v (a) The commercially available automatic stitchers do not have provision for more tha-n tive or six stapling heads, and therefore are not adapted for stitching sheet material which, due to its size or ultimate usage, require more ,thanl six stitches.

{(b) The automatic stitchers cannot place stitches any' closer together than the minimum center-to-center distane1between-adjacent' stapling heads which' is about .7n-21x27., Therefore when closer stitchingis required, a single headv must be used progressively. t f

1;(c) jAn automatic stitching machine has an initial cost which is -20 times more than lthat Vof a semi-automatic machine, therefore the labor savings of the automatic machinemay be outweighed by the amortization costs.

yIn v iew of Ithe foregoing, it is the primary object of my ,iaxeatinl te, provide. an. animatie. Single head.. stitcher.

y2,829,372 Patented Apr. 8, 1958 machine which can be utilized for multiple stitching operations.

Another object of my invention is to provide a method and apparatus for selectively'controlling the spacing and number of stitches.

Still another object of my invention is to provide stitching apparatus of the character described, which will be'.'V

In the accompanying drawings forming a part of this specification, and lin which like numerals are, employed to designate like parts throughout the same,

Fig. 1 is a front elevation of a stitcher embodying the i features of my invention, portions thereof being brokeny away to show details.

Fig. 2 is a top plan view of the stitchershown'in Fig.

l, taken as indicated by line 2-2 of Fig. 1.

. Fig. 3 is a cross-sectional view taken on line-3 3 of y Fig. 1 and showing the means employed for adjusting the, height of the conveyor bed of the stitcher.

Fig. 4 is an enlarged fragmentary cross-sectional view taken on line 4--4 of Fig. l showing details of the con f,

Vey-or drive mechanism.

Fig. 5 is an enlarged cross-sectional view taken "onf4 line 5 5 of Fig. 3 showing details of the height adjusting means.

Fig. 6 is an enlarged cross-sectional view taken on. line 6-6 of Fig. l and showing the idler sprocket adjusting means and portions of the conveyor bed structure'.

Fig. 7 is an enlarged cross-sectional view taken onk line 7-7 of Fig. 1 and showing details of the stitcher control mechanism.

Fig. 8 is an enlarged fragmentary cross-sectional View* ytaken on line 8-8 of Fig. 7. i

Fig. 9 is a fragmentary top plan view showing a modi 4 tied form of the invention.

Figs. 10, 11, 12 and 13 are electrical circuit diagrams showing Various forms of control for the stitcher operation.

Referring more particularly to Figs. 1-8, inclusive, the drawings, I have shown a stitcher machine which includes a table or bed, indicated generally by the 'reference character 20, which is mounted and secured on a The bed 20 may be a single at sheet of metal orA wood or preferably, as illustrated, it may be formed of three horizontally spaced strips 23, 24 and 25. Thematginal strips 23 and 24 are similar to each other and are A each provided with longitudinally-spaced laterally extending slots 26 in which are adjustably secured guide bars 27 and 28 by means of bolts 29. The guide bars are conj veniently formed of angle iron.

The strip 23 and the guide bar 27 extend beneath and in proximity to a stitcher head or stapling' head 30 Whic'hf,

is power driven by means of an electric motor drive 31 and clutch mechanism in a manner well known in the art.`

The stapling head 30 can be positioned or supported above the bed 20 in any suitable manner, and is shown supported upon a rigid, floor-engaging pedestal base 32,

which is yindependent of the frame 21 of the stitcher machine. sheet material which is conveyed on the bed 20. By mov-Y ing the guide bar 27 in the slots 26, the bar can lbe se` l lectively positioned to bring the edge of the sheet material into any desired 'relationship' to the stapling head '30."

The guide bar 28 is mounted on the bed strip 24 and has ,secured thereto laterally extendingsheet. engaging elements The guide bar'27 serves `to guide the edge ofA 3. 33 which are adapted to engage the edge of a stack of paper sheets and urge the sheets into abutment with the opposite guide bar 27. The elements 33 may be of any suitable form andare here shown as being arcuate leaf' springs which overlie the bed 20. The guide bar 28 is adjustable in thesame manner as the guide bar 27 so as to accommodate a variety of widths of paper sheets.

The central strip is disposed intermediate the strips 23 and 24 and spaced horizontally from the edges of said strips so as to define two spaced, parallel, longitudinallyextending slots 34 in therbed 20. The slots 34 provide clearance for the upper reach of a pair of endless roller chains 35 whichlie tiush with or slightly below the surface of the bed 20.

Each of the chains35 is trainedover a drive sprocket 36 and an idler` spocket 37. The drive sprockets 36 are secured to a common shaft 38 which is rotatably journalled in the frame 21. Power is transmitted to shaft 38 by means of an electric motor 39 which is connected,

by means of a belt and pulley transmission 40, to the high-speed shaft of a variable speed reducer 4l. The torque of the low-speed shaft of the speed reducer is transmitted by a chain and sprocket assembly 42 to an electrically actuated magnetic clutch 43 which is operativcly associated with the sprocket drive shaft 38.

In order to prevent sagging of the upper reach of the chain 35, the chain is supported by a series of idler rolls 44 which are journalled in the frame 21 at longitudinally spaced intervals.

The lower reach of each chain 35 is trained over a fixed idler sprocket 45 and an adjustablevidler sprocket 46. As best seen in Fig. 6, the sprockets 46 are rotatably secured to a horizontal shaft 47, the ends `of which are slidably retained `in vertically extending slots 4S in a U-shaped bracket 49k which is secu-red to the underside of the bed 20. The shaft 47 is provi-ded with a dependingJ stem 50 which is threaded internally to receive one end of a turnbuckle element 51, the other end of which threadedly engages a sleeve 52 which is rigidly secured 'to the bracket 49. The shaft 47 and sprockets 46 can be raised or lowered in response to 'rotation of element 5i' so as to keep the chain 35 under proper tension.

At predetermined points on the chain 35 are secured vertically and outwardly extending pins or posts 53. The posts 53 on one of the chains are each secured directly opposite corresponding posts 53 on the other of the chains 35 so that the posts form pairs. The distance hetween one pair of posts 53 and the following pair `of posts is uniform and fixed throughout the length of the chain, and is hereinafter referred to as loading length. It will be understood, however, that the number of pairs of posts may be increased or decreased as desired or required, provided that a uniform spacing between succeed ing pairs of posts is maintained.

The idler sprockets 37, heretofore mentioned, are fixed t to a shaft 54 which is rotatably journalled in the frame 21. A sprocket 55 is also fixed to the shaft 54 for ro tation therewith. An endless roller chain 56 is trained over sprocket 55 and over a sprocket 57 which is secured to a shaft 58 which is journalled in pedestal bearings 59.

The pedestal bearings 59 are mounted on a shelf or enclosure 60 beneath the bed 20 of the stitching machine. The relationship between` sprockets 55 and 57 must be such that the sprocket 57 will complete one revolution in response to a linear movement of chain 35 equal to the spacing between adjacentpairsy of posts S3. Thus, for example, if the distance between pairs of posts 53 is 24 links of chain 35, and sprockets 37 and 55 each have twelve teeth, then sprocket 57 should have 24 teeth so that it will rotate 180 for each` complte revolution of sprocket 550x 360 for a 24 link movement of the chain 35. synchronized with the rotationl of la control mechanism which willnowbe described. e

Fixedly secured to shaft 58 is disc 61 having .a coni- In this manner, the movement of the chains 35u;`

plementary disc 62 in axial abutment therewith. The disc.

62 is keyed to shaft 58 Aso as to be slidable thereon. A compression coil spring 63 is mounted on shaft 58 intermediate the disc 62 and the end of shaft 58 so as to yieldably maintain the disc 62 in clamping engagement with disc 61.

As best seen in Fig. 8, the ` discs 61 and 62 are adapted to releasably clamp a plurality of radially extending blades or interrupters 64 which are inserted between the opposed faces of the discs. The interrupters 64 may be of any convenient length and are, generally speaking, very narrow. It will be shown hereinafter that the width of a selected blade may be substantially increased to yobtain certain operating effects, when so desired. The blades 64 may be of metal, wood or any stiff self-supporting material. The interrupters 64 are clamped in selected angular positions between the discs depending upon thc stitching pattern which is desired. For convenience in identifying the positions `of the interrupters, the disc 62 is provided with circumferential indicia 65.

A photoelectric Vrelay 67 is mounted on a wall of the enclosure 60, and a light beam source 66 is mounted opposite thereto in such operative position that the light beam will be intercepted by the blades 64 during their angular rotation. The photo-electric system acts as a circuit switch, and the blades 64 act as switch actuators.

By reference to Fig. l0 it will be seen that the relay 67 forms an element of an electrical circuit which includes i a solenoid 68 and a micro-switch 69. The micro-switch 69 is mounted on the underside of the bed 2i) slightly in advance of the stapling head 30. The switch arm 70 of switch 69 extends through an opening 71 in the strip 23 and projects above the surface of the bed 20. The solenoid 68 is operatively associated with the clutch mechanism of the switchhead 30. A micro-switch 72 is also mounted on stitcher head 30 in operative association with any part thereof which moves cyclically in response to actuation of the stitcher head. inasmuch as such power-driven stitcher heads and the elements thereof are well known in the prior art, I have not shown or dcscribed the details thereof. An example of such a stitcher is the Acrne-Morrison Book Stitcher, Model N3A, sold by Acme Steel Company of' Chicago, Illinois. Examples of parts which move cyclically when the lstitcher head is actuated are the slide assembly, the wire draw bar assemblies and the plunger assembly. The micro-switch 72 is normally closed and is so located that its switch arm Y will be engaged in response to movement of a selected element of the stitcher head 30.

As shown in Fig. 10, the motor 39, which drives the conveyor chains 35, and the stitcher motor 31 are connected in parallel in the power supply circuit, each having a circuit switch 73. The photo-electric relay 67 is connected across the power supply and is also provided with a switch 73. The relay is normally open and is in series with the solenoid 68 and the normally open microswitch 69. The magnetic clutch 43 is in series with normally closed micro-switch 72 and is energized through a current converter 74 which is connected to the power supply.

The operation of the apparatus is as follows. First, the interrupters 64 are placed in selected positions of angularity between the clamping discs 6162. The quantity and position of the interrupters is determinative of the stitching pattern which will result. Assume that the sheet material to be wire stitched has a length equivalent to 22 links of chain 35, or 22 inches if each link is an inch. If the interrupters are positioned in the manner shown in Fig. 8, the following will occur. The stack of sheet material is fed onto the bed 20, either manually or mechanically, with one edge thereof abutting the guide bar 27. The sheets lie on the bed until a pair of posts 53 on moving chains 35 engage the rear edge of the stack and move it forwardly, as shown by the arrow, toward the stitcher head 30, the space between pairs of posts being t 24 inches. The indicia 65 on disc 62 are synchronized with the position of posts 53 relative to the stitcher head 30. Thus, when a pair of posts 53 is almost directly opposite the stitcher head 30, the disc 62 will have been rotated to a position where a blade 64in index position 24 would have interrupted the light beam. Accordingly, the blade 64 in index position 1 (Fig. 8) would interrupt the light lbeam and energize relay 67 when the posts 53 have traveled one inch beyond the stitcher head or 23 inches forwardly of the rear edge of the sheet material. Inasmuch as the stack is only 22 inches in length, the forward edge of the stack would not yet be under the stitcher head 30 at this time. Therefore, the micro-switch 69 in bed 20 would remain open'and prevent energzation of the stitcher solenoid 68 and therefore no stitching would occur.

The stack of sheet material continues to advance until the interrupter 64 in index position 4 interrupts the photoelectric light beam. The stack now underlies the stitcher head 30 and overlies the micro-switch 69, causing it to close. Therefore, solenoid 68 is energized and actuates the clutch mechanism of the stitcher head causing operation thereof. When the stitcher head is thus actuated, it causes micro-switch 72 to be opened and thus .interrupt the electrical circuit to magnetic clutch 43. The stack is momentarily arrested in movement during the stitching operation, and as soon as the stitchingv operation is completed, the magnetic clutch circuit is reestablished by micro-switch 72 and the chains 35 and the stack of sheet material continue to advance. The 'first stitch is thus effected 4 inches rearwardly of the preceding pair of posts SSequivalent to 2 inches from the forward edge of the stack.

Similarly, the interrupters 64 in the index positions 7, 8, 13, 17, 19 and 22 will cause a stitch to be made in the stack at points 5", 6", 1l", 15, 17" and 20" from the forward edge of the stack, respectively.` Thus lit will be apparent that any pattern of stitches can be obtained by proper positioning of the requisite quantity of interrupter blades 64. It will Ibe understood that normally there would be no reason for inserting an interrupter in a nonoperative position, such as index position l if the stack of sheet material is less than 24 inches in length, as in the example given. However, the example serves to indicate the function of the micro-switch 69 in preventing-any stitching operation unless there is sheet material present to be stitched. The example also shows that it is possible to run stacks of varying lengths through the stitching operation and have more stitches in the longer stacks than in the shorter stacks, with but a single setting of the interrupters 64, and without causing any wasted-operation of the stitcher head 30.

The rate of travel of the chains 35 is to a great extent necessarily coordinated with the rapidity'of the stitcher head cycle. Thus, if the stitcher cycle is one-half second and the staples are one-half inch in width, the preferred maximum conveyor speed would generally be one inch per second or vefeet per minute. This would permit one stitch to be immediately adjacent the preceding stitch during continuous operationv of the stitcher head, :which-is sometimes desired. l If such continuous stitcher operation is desired, during any part of the stitching pattern, one or more of the blades 64 are made wider so as to interrupt the light beam for a definite time interval. Thus, if it is desired that the stitching pattern include three continuous stitches, a blade 64 would be used which, in the example given, would be of sufficient width to interrupt the light beam for 11/2 seconds and thus keep the solenoid 68 energized for a sufficient length of time to cause stitcher head 30 to operate continuously for 11/2 seconds. If the speed of the conveyor chains 35 were increased slightly by means of the variable speed reducer 41, then the stitches would be spaced a slight distance from each other during continuous operation of the stitcher head 30.

Thus, the stitching machine is very flexible in operation. as any desired pattern of stitches can be obtained by varying the rate of travel of the chains 35 and varying the number, position and width' of the interrupters 64. j

In order to permit the height of the bed 20 to be adjusted in relation to the stitching head 30, so as to accommodate stacks of sheet material of varying thicknesses, height adjusting means are provided on the legs 22, as shown in detail in Figs. 3 and 5.

Each of the legs 22 has a foot portion 75 rigidly secured thereto as by welding. The foot is preferably a solid cube of metal provided with a vertical `bore 76 which is counter-bored as at 77 to form an annular shoulder 78. The piece '75 is also counterlbored from the underside thereof and threaded as at 79. A stud S0 having a flat, floor-engaging head 81 is threadedly secured in the bore 79Vof the piece 75. The stud 8!) has a central longitudinally extending cavity 82 of square cross-section. bevel or miter gear 83 having a cylindrical hub 84 and a square shaft is mounted on top of the piece 75. The hub 84 is provided with a circumferential recess 86 and is rotatably secured in the bore 77 by means of a dog-point screw 87. The square shaft 85 extends through bore 76 into telescoping engagement with cavity 82 Vof stud 80.

Each of the gears 83 is in mesh with a miter gear 89 which is xedly secured to a shaft 88 which is journalledv between each pair of legs 22. An endless chain 9i) is trained over a sprocket 91 on each of the shafts 88 and serves to transmit the rotation of one shaft 88 to the other shaft 88. A crank arm 92 is secured to one of the shafts 88 to provide for manual rotation of the shaft and the gears 89. Rotation of the gears 89 causes axial rotation of gears 83 which is transmitted simultaneously to all four of the studs 80. Rotation of the studs will cause raising or lowering of the legs 22 and a corresponding change in the elevation of the conveyor bed 20. j

In Fig. 11 I have illustrated a modification of my invention in which a normally open micro-switch 93 is utilized as a circuit element in lieu of the photo-electric relay 67. In this form of the invention, the switch arm 94 will be disposed in the path of movement of the actuator Iblades 64 so as to close the circuit to the solenoid 68 and thus actuate the stitcher head 39 in response to engagement of the blades with the switch arm.

In Fig. 12 I have shown another modification which is similar to that of Fig. 11 except that I eliminate microswitch 72 in the magnetic clutch circuit. In this form I employ a double pole-double throw micro-switch Y. 95,

which, when engaged by the interrupter blades 64, will simultaneously close the electrical circuit to solenoid 68 and open the electrical circuit to magnetic clutch 43.

Aacting in operation. It is slightly less expensive to manufacture, but it is not as versatile in performance as the preferred embodiment heretofore described. In this form of the invention, I do not employ the interrupter blades 64 and the-sprocket drive therefor, but, instead use Ya controlarrangementj comprising a plurality of microswitches 96 which are connected in parallel in the electrical circuit to solenoid 68. The switches are adjustably secured to a bar 97 which extends longitudinally in overlying relation to the bed 20 in a plane lying between and parallel to the spaced chains 35. l he bar 97 is supported in an elevated position by means of a bracket 98 which is rigidly secured to the frame 21 of the stitching machine.

The bar 97 is preferably slightly longer than the loading length or distance between adjacent pairs of posts 53 and is situated in a predetermined position relative to its distance from the stapling head 30.

The micro-switches 96 can ybe mounted on both sides of bar 97 so as to obtain a stitching sequence or pattern which will depend upon the quantity and spacing of the there is sheet material under the head 30, which will maintain micro-switch 69 closed. lf-,there is no stack of paper or other sheet materiall overlying switch 69, then the stapling head 30 will not operate.

Thus, as the posts 53 and web 100 advance toward the head 30, the web will successively engage the switch arms 99, and the stapling head 30 will be actuated to effect a stitching pattern which will conform directly to the number and longitudinal spacing of switches 96.

It will also be apparent, that if there be random lengths of stacks of sheet material, then a stitching pattern can be established which will be effective to produce more stitches in the longer lengths than in the shorter, if desired, as one or more of the micro-switches 96 'can be so located as to be engaged -by rod 100 when the forward edges of shorter stacks do not yet overlie micro-switch 69.

It will thus be apparent that I have provided a method and apparatus for effecting automatic multiple stitching by means of a single stitcher-head. Inasmuch as stitcher headsrequire frequent attention due to jamming, fouling, and breakage of wire, it is a distinct advantage to employ a single head rather than multiple heads. Thus, if five heads are used, it is safe to say that there are tive times as many chances for shut down of the machine as if only one head is-used. p

Further, the multiple head stitchers can be spaced no closer than their own bulk permits. This will ordinarily mean that the center-to-center distance of the stitches cannot be less than about 21/2 inches. As heretofore indicated my method and apparatus is subject to no such limitation, and stitches can be placed as close together as is desired. This feature is of particular importance camara driven stitcher head, endless means for conveying stacks of sheet material through saidV head, adjustable means for selectively establishing a sequential stitcher actuating pattern in response to anylmovement of said conveying in the stitching of narrow pads such as sales books, order blanks and restaurant checks, which often are less three inches in width. v

It will also be noted that any number of stitches can be produced with but a single'head. Thus,if it is necesthan sary to have ten stitches it is merely necessary to establish y the control mechanism for ten stitches, either through i use of the actuating blades 64 orfby means of ten microswitches 96. In contrast, thereto, the provision of a ten-I means,'acontrol circuit for actuating said' stitcher head, first switch means in said control circuit operable by said adjustable means in response to movement of said conveying means to prepare said control circuit, and normallyopen second switch means in series with said first switch means and operably disposed in the path of movement ot said sheet material for closing said control circuit in response to passage of said sheet material through said head.

2. A combination as dened in claim l, including means provided on said endless means for maintaining successive stacks of sheet material in uniformly-spaced relationship to each other.

3. A combination as defined in claim 1, including brake means for arresting movement of said endless means in response to actuation of said stitcher head.

4. In a stitching machine, 'the combination of a powerdriven stitcher head, an electrical actuating circuit associated with said stitcher head, a photo-sensitive switch in said circuit, a conveyor for feeding successive stacks of sheet material to said stitcher head, an adjustable lightbeam interrupter operatively associated with said switch to selectively close said circuit, and means responsive to movement of said conveyor for driving said light-beam interrupter to establish a selected stitcher actuating pattern.

5. A combination as defined in claim 4 wherein said light-beam interrupter comprises a plurality of opaque blades and means for adjustably securing said blades for angular rotation relatively to saidk switch.

6. A combination as defined in claim 5 wherein said blades are disposed in angularly spaced relationship to each other.

7. In a stitching machine, the combination of a powerdriven stitcher head, an electrical actuating circuit associated with said stitcher head, a photo-sensitive switch in said circuit, a conveyor for feeding successive stacks of sheet material to said stitcher head, an adjustable lightbeam interrupter operatively associated with said switch, said light-beam interrupter establishing a selected stitcher actuating pattern and cyclically movable into switchclosing position in response to movement of said conveyor, and means for maintaining each of said stacks at a fixed distance from its preceding stack.

References Cited in the `file of this patent UNITED STATES PATENTS 2,017,512 Reiser e Oct. 15, 1935 2,197,371 Thedford Apr. 16, 1940 2,304,510 Rosenmund Dec. 8, 1942 2,482,370 Rosenmund Sept. 20, 1949 2,569,355 Tubbs Sept. 25, 1951 2,578,936 Kingsley Dec. 18, 1951 l2,631,283 Cranston Mar. 17, 1953

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