US2700364A - Work controlled glue impression roll release - Google Patents

Description

P. E. ElScHr-:R 2,700,364

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Jan. 25, 1955 WORK CONTROLLEUGLUE IMPRESSION ROLL RELEASE Filed July 18, 1952 Jan. 25, 1955 P. E. FlscH-ER 2,700,364

WORK CONTROLLED GLUE IMPRESSION ROLLI RELEASE l Filed .my 18. 1952 2 sheets-sheet 2 oFF oN INVENTOR. PAUL E. /scHL-R Flc. 2.

United States Patent WORK CONTRGLLED GLIUE IlVIP-RESSION ROLL RELEASE Claims. (Cl. 118-1) This invention relates to improvements in machines that are used for making boxes, cartons, envelopes and the like, of paper and other brous material in which areas of glue or adhesive are applied to pre-cut pieces of paper, ber, cellophane, textiles or the like. In previous apparatus for making articles of sheet materials which are adhesively secured together, the practice has been to apply adhesive to certain areas that are to be glued together by means of rolls that are provided with appropriately shaped adhesive impression pads. The sheets to which the adhesive is to be applied are fed along a straight line course through a suitable machine and may either be cut beforehand and fed one at a time orA may be cut by the machine itself, and after having been cut, severed, shaped, or punched are fed along a straight line lcourse of action through the machine. As the piece or pieces move along at a certain stage in the machine they pass between pairs of opposed rollers for applying glue, either to the entire piece or to selected areas of each piece. For this purpose the glue impression roller may have a continuous periphery, as where an unbroken line of glue is applied, or it may be provided with shaped pads for applying glue to only selected areas where the pad'comes in contact with the sheet. The glueis applied to the roller by glue feeding rolls of known design. In order that the glue may be pressed rmly onto the sheet, the sheet is supported opposite the glue applying roll by a supporting roll.

In such prior machines where the strip is severed into discrete lengths, it is undesirable to have the supporting roller run in contact with the glue impressing roller, and accordingly, the glue carrying rollersrare provided with pads projecting from the periphery thereof throughout certain arcuate segments and only these segments run in contact with the sheet, the sheet meanwhile being held against the glue impression roller by the supportingy roller. Such devices work satisfactorily where the sepa-rated sheets are fed in properly timed relation, but occasionally a sheet may not be fed where it is supposed to be, or may become jammed or misplaced. In such case the supporting or presser roller may run in contact withthe glue impression roller which is covered withgluefand in this way the presser roller is coated with glue from the glue impression roller, and as subsequent sheets of material come through the machine, -glue may be applied to both sides of the sheet. This is a disadvantage since it causes the sheet to stick to unwanted portions of adjacent sheets. Efforts have been made to overcome this difficulty in prior machines by making the presser roller in a form such that it has thin circumferential grooves around it rather than a smooth or'continuous surface. This is onlya partial solutionof the problem since the glue is applied to the crests of the ridges, where the sheet ow is interrupted.

Other efforts have been made to overcome this problem by providing a continuous cleansing arrangement forthe presser rollers so that if glue should be rolled onto it due to the absence of a sheet at the appropriate `time, the presser roller will then be cleaned automatically. However, Vthis is a makeshift solution and the results are not very satisfactory.

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It is an object of the present invention to overcome the diiculties aforesaid and to provide improvements in glue impression roll devices for box and carton-making machines, envelope-making machines and the like.

It is a further object of the invention to provide a pressure roll release for withdrawing the presser roller out of proximity with the glue impression roll when there is no work sheet available between them at the time that the sheet should be there.

It is a further object of the invention to provide an improved presser roll release for glue impression devices.

It is another object of the invention to provide an auf tomatic device operating in timed relation to the flow of separated sheetsV going through a machine, for withdrawing the presser roll from a position adjacent the glue impression roll when a sheet is absent from the machine at thetime that it should be owing through the machine. l

Other and further objects of the invention are those inherent in the apparatusherein illustrated, described and claimed.

The invention is illustrated with reference to the drawings in which corresponding numerals refer to the same parts and in which Figure l is a 'fragmentary longitudinal sectional view of a part of a typical box or envelope making machine in which the improvements of the present invention have been applied;

Figure 2 is a wiring diagram and enlarged fragmentary sectional view of a portion of the machine shown in Figure l, showing the elements in connected relationship;

Figure 3 isa diagrammatic view or sequence chart.

Referring to Figure l, a representative machine on which the improvements of the present invention may be applied is'there illustrated. This machine is of well known type and may be used for making boxes, cartons or the like, that are made from pre-cut blanks of suitable shape vfor foldingV in the machine after having had glue applied to selected portions of the blank. Thus, the machine has al frame generally designated 10 and at one end .under the bracket l171 there is provided a feeding apparatus which includes a chute 12, afeed roll 13 and a feed `roll brush 14. Upon the machine there is also a horizontal bed 15, and a feed belt 16 running over the rollers 18, 19, 2t) and 21. The beltusually is provided with projections from its outer'surface and is run in timed relation to the feeding roller 13. As a result, the pre-cut blanks which are appropriately stacked in the chute 12 are drawn olf one at a time and onto the belt 16. As the belt proceeds in the direction of arrow 22 in its upper course of travel, the fingers or projections at `24 lrun into abutment with the trailingedge of the blank andthus carry the blanks along in the'direction of arrow 22, in appropriately spaced relationas determined by the spacing of the ngers 24.

The blanks -are shown schematically in Figure 3 where the blank B1 is followed by the blank B3. In the vspace to the ``right of blank B1, there -should have been feda blank under the bracket B2, but itmay be assumed that this was a fault in themachine operation which caused no blank to be fed at, this point, but subsequently other blanks wereffed at B3 and B4. Thus, in the operation of the machine the blanks B1, B3, etc-should move along in spaced relation.

Referring again to IFigure l under the bracket 25 are a plurality of feed rolls. Thus, feed creasing or work rolls 2.6, 27, 28, 29, 30 and 31 operating'in pairs, being spaced above and below the line of travel 32 of the .blanks off Vthe end 15A of the guide bed 15. Thus, as the blanks are moved along the bed 15 by operation of thebelt 16vand its fingers /24-24, the blanks are fed directly into the nip of rolls 26 and 27 and are carried by'these rolls which rotate as shown by the arrows 34. Hence, the rolls 26 and 27 pick up theleading edgeof theblanks as they move along and carry them in the direction of arrow 22 andrintovtheznipof rolls-28 and 29` which likewise rotate as :shown vbythe arrows 65. Further along, then'blank goes between the rolls 30 and 31, also rotating in the direction of arrows 36. These pairs of rolls 26-27; 28-29; and 30-31 may be utilized for creasing or otherwise producing work operations on the blanks as they pass along the course of travel denoted by the line 32.

Under the bracket 40 are shown the glue impression devices of the machine. The glue impression apparatus includes an upper roll 41 journalled at 42, and this roll of the present apparatus is of the same general character as heretofore used in the prior art. It may have a continuous glue impression surface or may be provided, as illustrated, throughout segments of its surface with pads of appropriate dimensions for spotting appropriate shapes and areas of adhesive onto the material passing through the machine. Roll 41 and shaft 42 are held by a bracket 44 on the machine. Adjacent the roll 41 there are additional guiding rolls 46 over which a belt or belts 48 run. The belt or belts 48 may be considered as running alongside of the glue impression roll. The glue impression roll in the usual machine is made so that it can be shifted and adjusted sideways, its width and shape changed, if desired, and pads of different shapes and sizes placed on its periphery for applying adhesive only in the appropriate places to the sheets going through the machine.

Referring to Figure l and to the lower part of Figure 2 particularly, the glue impression roll will be observed at 41 and it is in this instance provided with pads 56 and 57 set diametrically opposite each other on the peripheral surface of the roll 41. It will be understood that the shape and the size and the number of pads 56 and 57 that are placed around the roll depend entirely upon the particular gluing job being done.

The sheets of cardboard, paper or the like after being operated upon by the glue impression apparatus 40 are carried between the belt 48 and another belt 47 carried by rollers on the machine, of which roller 43 is shown in the lower part of Figure 2. The two belts 47 and 48 thus run back to back and then pick up the sheets as they are delivered and carry them along through the machine. The rollers 49 and 52 are spaced above and below the belts 47 and 48 and serve to apply pressure to the belts and hence to the work running between them.

Beneath the glue impression roll 41 there is positioned a presser roller 60 journalled on the shaft 61, the shaft in turn being carried by a bent lever 62 mounted on the shaft 64. The bent lever 62 is thus permitted to swing about the shaft 64 arcuately in the direction of the arrows 65 and 66. Also pivoted upon the shaft 64 is a lever arm 67 which is unattached to the bent lever 62, being simply pivoted on the same shaft 64 as the lever 62. The arm 67 has a pivot pin at 68 and another pivot pin at 69, the latter being connected by the link 70 to the core 71 of a solenoid generally designated 72 that is attached at 73-73 to the frame of the machine. The solenoid mechanism 72 has a winding 74 which, when energized, causes the core 71 to be moved in the direction of arrow 75, thus pulling on link 70 and hence causing the lever 67 to be moved in the direction of arrow 76. Upon the frame 10 there is a bracket at 78 having a pivot at 79. To the pivot 79 there is attached the lower link 80 of a toggle having an upper link 81 pivotally attached at 82 to the bent lever 62. The center pivot 83 of the toggle is connected by a link 85 to the pivot 68 on the solenoid actuated lever 67. The center pivot 83 of the toggle has one end of a spring 86 attached to it, the spring being anchored at 87 on the frame 10. The back position of travel of the toggle 80-81 is determined by the adjustment screw 88 that is mounted in the ear 89 on bracket 78. The spring 86 accordingly pulls the toggle 80-81 in the direction of the arrow 90 until the link 80 runs into engagement with the end of screw 88, which being adjustable permits any amount of back travel of the toggle in the direction of arrow 90.

The toggle 80-81 accordingly determines the distance between the pivots 79 and 82 and hence determines the position of the bent arm 62 on which the shaft 61 and the presser roller 60 are mounted for rotation. By adjusting the screw 88 the arm 62 may thus be positioned as desired until the presser roller 60 runs with appropriate contact against the glue impression pads 56 and 57 of the glue impression roller 41. It will be understood, of course, that when the pads 56 and 57 are running to a position where they would contact the presser roller 60, the precut blanks going through the machine should at such time be between the pads 56-57 and the roller 60. Otherwise,

the glue would be applied to the roller 60. However, when the solenoid 72 is energized, the movement of arm 67 in the direction of arrow 76 pulls the toggle 80-81 in a direction opposite arrow 90, thereby causing the arm 62 to be brought smartly down in the direction of arrow 65, thus retracting the presser roller 60 away from any position where it would contact the glue impression pads 56 and 57.

According to the present invention the roller 60 is thus made retractable and controls, both automatic and manual, are provided so that the roller 60 may be retracted at will or automatically should the machine fail to feed a blank, to which glue should be applied, at an appropriate time when the glue impression pads 56 and 57 are in a position to apply glue thereto. For accomplishing this control of the presser roll 60 the following mechanisms and circuits are provided:

On the shaft 42 on which the glue impression roll 41 is carried there are provided a plurality of cams 94 and 95 which are arranged to operate the roller 96 of a cam operated electrical switch generally designated 98 carried on a bracket 99 connected to the frame 10. As many cams 94-95 are provided as there are provided glue irnpression pads 56-57 on the periphery of the glue impression roll 41 and the cams 94-95 are spaced so that an appropriate angle 100-100 is provided between the leading edge of each of the cams 94 or 95 and the point where the roller 96 is located when corresponding pads 56 or 57 first come into contact with the pressure roller 60. This times the operation of the switch 98 appropriately so that the switch is operated when the pads 56 and 57 reach a certain position, as will be more fully explained. As a further means of adjustment the switch 98 is provided with a slotted mounting at 101 so as to allow precise adjustment of this timing. At another position along the machine, as at the line 102-103, which intersects the line of travel 22 of the sheets going through the machine, there is provided a second sensing device which may be either mechanical or photoelectric, as shown in the illustrative form of the invention. Thus, in Figures l and 2 a lamp is provided at 105 and a photoelectric cell at 106, each of these being mounted upon an appropriate slotted mounting 105A for the lamp and 106A for the photoelectric cell so as to provide a precise adjustment back and forth in the direction of arrow 108. Referring to the wiring diagram shown in the upper part of Figure 2, power is supplied over lines L1 and L2. A first circuit extends from junction 109 on line L1 through a manually operable on or off switch 110 and thence through junction 111 to the primary 112 of a transformer generally designated 113 and thence to line L2. The transformer has a low voltage secondary 114 which is connected through low voltage lines 115 to the lamp 105. If desired, the transformer 113 may be eliminated and power supply at the voltage of lines L1 and L2 supplied directly over line 116 and L2 to the lamp 105.

From junction 111 a circuit also extends over line 117 to a terminal 118 of the photoelectric amplifier generally designated 120. The other supply terminal 121 of the amplifier being connected over line 122 to junction 123 on line L2. The photoelectric amplifier has a pair of input terminals 125 and 126 that are connected through the shielded cable 127 to the terminals 128 and 129 of the photoelectric cell 106. The signal derived from the cell 106 is thus applied through the shielded leads 127 to terminals 125 and 126 and is amplified, the output being delivered at the output terminals 130 and 131. These terminals are connected directly to a coil 132 of the relay generally designated 133. The relay 133 has one normally open contact 133A. Thus, a circuit extends from junction 134 on line L1 through 135 to one terminal of the relay contact 133A and thence through the other terminal thereof to junction 136 and to the terminal 98B of the cam operated switch 98 that has been referred to previously. The switch 98 is shown in the wiring diagram portion of Figure 2 and also in the vertical sectional portion at the lower part. It will be understood that it is the same switch and is cam operated as previously described. The opposite terminal 98A of the switch 98 is a junction that is connected to the coil 138 of the relay generally designated 139. This relay has two normally open contacts 139A and 139B. The opposite side of the coil 138 of relay 139 is connected through line 140 to junction 141 on line L2. From junction 144 on line L1 a circuit extends at 145 through the manually operable from the line 164 to the line 165.

1 end at 171.

" ergized).

normally open push-button switch 146 and thence through line `147 to junction 98A. From junction l136 a circuit extends at 148 through the contacts 139A`of relay y139 and thence to junction 98A. From junction 150 on line L1 a circuit extends at 151 through the contact 139B of the relay 139, thence to terminal 152. A circuit then extends to the lamp 153, to the terminal 154, and'through line 155 to junction 156 on line L2. From terminal 152 and 154 lines are also connected through cable 158 -to the terminals of winding 74 on the solenoid 72.

Referring to Figure 3 there is illustrated `the sequence of operation of the cam operated switch 98 and of the lphotoelectric cell operated sensing device S- 106 and ,bracket so designated and it will be assumed that due to improper feeding of the machine or other causes, no blank has been fed at that position. In Figure3 the blank B1 extends from the line 162 to the line 163 and theA glue spot on the blank may be assumed to extend It will be understood, of course, that a blank may have more than one spot of glue placed on it and that the length and disposition of the spots of glue is dependent entirely upon the particular carton, cover, box, envelope, etc. that is being sent through the machine. The area and extent of such glue spots are determined by the area and extent of the glue 4applying pads 56 and 57 on the roller 41. in theillustration herein the roller 41 has two such glue applying pads 56 and 57 that are usually made of rubber of suitable density and resilience. Likewise, in the present illustration it will be assumed that one revolution of the roller 41 applies the glue to two successive blanks. Thus,

the pad 57 of the roller is shown as just about to apply :40

the glue spot GB1 of Figure 3 to the blank`B1. Referring to Figure 2 the glue spot GB1 will begin at the line 164 and as the glue impression roller 41 turns the blank B1 will be carried along and the glue applied until the end of the pad 57 reaches the line 165 corre-y sponding to the end of pad 57. The blank B1 will then continue to the left through the machine and its trailing edge 163 will graduallyvpass out from between the glue impression roll 41 and the presser roll 60 and be carried along by the belts `47--48.

The nger 24 which pushed the trailing edge 163 of the blank B1is shown in Figure 2 at '24131. It has already proceeded around the roller 19. It will be assumed that the next blank B2 has not been fed Vdue to some malfunctioning of the machine. The leading edge of this blank should have occurred at168 and with the blank in place glue would then be applied beginning at 169, the glue spot continuing to 170 (see Figure 3) and the trailing edge of the (assumed missing) blank would However, due to failure of feeding this Vblank B3 is assumed not present, and hence the light beam L is uninterrupted at position 16S. This vultimately has the effect 'of retracting the-presser roll-60 out of the way at a time when that-position 169 normally would have reached the nip between the'gluefimpression pad 56 andy the 'roll'60. lt will benderstood, of course, that the belt 16, the rolls 26lthr'ough 31 and the rolls 41 and 60, as well as the belts 47 and 48 all Vare synchronized so as to produce uniform travel through the machine. i

Referring again to Figure 3, it will be assumed that succeeding blanks B3, B4 are fed properly in spaced relation.

When the photoelectric cell 106 is illuminated the input at terminals 12S-126 is ampliiied by the amplifier 120 and current is then sent through the coil 132, 'thus energizing that coil. This causes the closure of contact 133A. Similarly, when the photoelectric cell 106 is darkened (as when a blank interrupts the beam of light L from the lamp 105 to the photocell 106), the coil 132 is de-energized and the contact 133A opens. It may be noted parenthetically that the relay 133 is thus designated a normally open relay (openwhen de-en- If desired, this may be reversed, so as to be normally closed, in which case the amplier 120 shall include an intermediate i"relay fallowi'ng E the coil; ,il 2 5to be de-energized,v when tlie 'photocellf106' fis illuminated. Such reversal of relay contacts vwill `be-i'm'de'rst'od to be within the provinceof the electricaldesignenI Likewise, if desired, a` mechanical sensing nger Vmay be substituted for the `lamp and vpliotocell J106. Tt would ride upon each blank a/sitpasseshroughthe nia'- chine and be'lifted bythe blank, thus,causinglthe closure Vof a -switch corresponding to 133A whenever a bla'nk is fed. The photoelectric sensing unit is preferred y"since it is weightless and is vthus capable "o' handling l'exceedingly iine materials, -sch as 'thin p"z`ip`er.

Referring to Figures 2 and 3, :it will therefore be assumed that the rstblank Bil is proceeding throughithe machine as illustrated in'Figu're 2 Vand vglu'e -is about to be applied to thespot G'Bl bythe glue impressiohfp'ad '57, the blank B1 being supported against the 'glue yifnpression pad by the pesserroll ,60 whichis in -thepsitin shown. As the leadi'ngedg'e- 162 of the blank AB1 Vpproached the lightbeam-L, it interrupted lthe ylight'heath thereby darkening the photocell li106 'and consequently cleenergizing the coil 132. This caused cohfa'ets 133At'o `be opened. As Yithe blank B1 proceededftowards [the rolls 41-60 rthe cam'9`5 `ranfunder the wheel `96jbf switch l98, thus causing the closure of 'the switch I98B. A circuit 'would have been vestablished 'through lthe gcoil v13s of relay 139, but'the Contact `133A was open and therefor'ecoil138 was not de-energized. Had vit 'been v.r'rer'gizedit Would Ahave established'its Vo`vvnjself-"sustaining circuit `through contact,139A andheld the ,circuiteven `after thecam switch 9'8B="opened lal'idyvouldthave iclosed thecontact 139B renergizing the fsolenoid '72. VHowever, all of this wasinte'rrupted and prevented due -to the-'fact that the photoelectric sensing vsystem had not energized the'relay 133. As Vthe't'railing edge `163'o'f"the"bla'rk B1 lamp 105 again was'cast'u'p'on the Lphotocell "106, and

accordingly in -the space `between the fft'railing ilend 163 and the leadingl edge 168 o'ffthetassumed) nmissing blank,

'the photocell "106r is illuminated, causing 4relay '(133 'to be'energizyed and contact 133A to be closed. This pre'- "pares va circuit from line 'L1 through critactf133A, junction 136, but the circuit is not at -tht ti'rne completed Il ;f`l:cai`1s`e the contact'sp98B are ythenfopen. Asl'the 'machine proceeds, and assuming `that there 'is no leading edge'of ajblank at 1ine168,lthe position of themis'sing lblank B2, the photocell-106 continues-tobeillurninted,

even whenthatleading'edge16Sfreachs and passes the positionsshown in Figure 2. Consequently,the-photoelectricallyl controlled relay "1733 continues energized and its contact 133A continues to be closed.y Then vasUth'e position 168 of the missing blank proceedstwards the glue 'impression roll 41a`ndthep`resser roll60,'and just prior to the time the glue v impression pad 56 ycornes @around to ythe `position where it 1shall v`apply glue, I*the leadin'gfedge o f the vca'r'n'f94 vrunsn'u'nder the switch98, thus closing said switch'at 1.74. When this occurs acir- 'cut isimmediately completed'from junction 136"thrug`l1 the terminal 98A, coil y133 ofrelay 139 and 4th'rc'nughline 140 to junction :141 on line L2.. Relay 138, therefore,

xenergizes and closes bothof its normally open contacts 139A and 139B. Contact 139A is in parallel with the cam `operated switchf98Bran`d hence maintains thefcirvcuit throughthe `coil 139 even after the'camfswitch 98 has'rbeenopened 'at position 175, seeFig'ure 3. The other contact 139B of relay l'139, completes a'circuit'fror'n junction on line L1 through line 151, contacts 139B, `'therminal 152,y through ,the solenoid coil 74 ofsolenoid `72, thence to junction `154, line Hto junction 156 on lin'e L2. The solenoid 72 accordingly is energized.` jAt the same time the pilot lamp 153 is illuminated. The 'e'nergization of the solenoid 72 causes the toggle links80 V871 to be pulled to the right, thus smartly drawing down 'tacts 133Afand relay 139 is likewise dee'nergiz'ed, therelby opening its selfsustaining "contacts 139A A'and the solenoid-lamp control contact 139B. As the properly fed blank B3 proceeds again the cam switch 98 is operated by the leading edge of cam 95 running under the roller 96 at position 178, thus closing the cam switch 98A. However, this does not complete a circuit through relay 139 since the photoelectric cell 106 is then dark due to the properly fed blank B3 interrupting the beam. Accordingly, relay 133 which is controlled by the phootelectric cell is de-energized and its contacts 133 are open.

For the purpose of adjusting the machine or of otherwise withdrawing the roll 60 away from the roll 41, there is provided the manually controlled push-button switch 146 which, when pushed, closes a circuit from junction 144 on line L1 to line 145, switch 146, line 147 to junction 98A, thence through the relay coil 138 of relay 139 and line 140 to junction 141 and line L2. This energizes the relay 139 so long as the button 146 is held closed,

and accordingly illuminates the lamp 153 and energizes the solenoid 72, the latter effecting withdrawal of the roll 60 to a lowered position out of the way of the pads 56 and 57 on the roller 41.

In the illustrated form of the invention the presser roll 60 is shown as being retractible from adjacent the adhesive impression roll 41, but it will be understood that the adhesive impression roll may be made so retractible and the presser roll 60 made stationary, if desired, although usually this is less convenient because roll 41 is heavier and because of the adhesive feeding means which must be operated in cooperation with it would also then be movable. Likewise, both rolls may be mounted for relative movement toward and away from each other. I prefer to journal the adhesive impression roll for rotation on a constant axis of rotation, and to mount the presser roll for movement toward and away from the adhesive impression roll for applying the necessary pressure to the under side of the sheet.

In the form of invention illustrated, the biasing spring 86 holds the rolls together and the power device or solenoid 72 pulls them apart. If desired, the mounting of the presser roll (or of both rolls or the adhesive impression roll if the machine is so laid out) may be made so that pressure is held by the action of the power means (here illustrated as the solenoid 72) and a resilient bias then used for pulling the,two rolls relatively away from each other -at such times as the sensing devices may indicate as when a sheet has not been properly fed. It will be understood that this may be a mere reversal of the form shown.

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that I do not limit myself to the specific embodiments herein.

What I claim is:

1. In a device having an adhesive impression roll and a presser roll positioned to operate in rolling contact, and means for feeding pre-cut sheets serially in spaced relation for movement between said rolls for applying adhesive to selected portions thereof, the improvement comprising means mounting said rolls for relative movement toward and away from each other, said rolls in one position being in resilient rolling contact with each other and in another position being retracted out of contact with each other, means for normally biasing said rolls to one of said positions and power means responsive to the rotation of said adhesive impression roll for moving the rolls from said normally biased position to the other position, sensing means responsive to the progression of sheets moving serially between said rolls and connected to said power means for rendering said power means inoperative.

2. In a device having an adhesive impression roll and a presser roll positioned to operate in rolling contact, and means for feeding pre-cut sheets serially in spaced relation for movement between said rolls for applying adhesive to selected portions thereof, the improvement comprising said adhesive impression roll being journalled for rot-ation in a fixed position, and said presser roll being mounted upon-supporting arms for movement from a position in rolling contact with said adhesive impression roll to another position out of rolling contact therewith, toggle means connected to said supporting arms for moving the supporting arms and the presser roll thereon toward and -away from said adhesive impression roll, power means connected to said toggle means for moving said presser roll to said other position and sensing means responsive to the progression of sheets moving serially between said rolls and connected to said power means for the actuation thereof.

3. The apparatus of claim 2 further characterized in that said toggle means is resiliently biased to one position for holding the presser roll in rolling contact with the adhesive impression roll and said power means is connected to said toggle for moving the toggle to broken position for moving the supporting arms to a position such that the presser roll is out of contact with said adhesive impression roll.

4. The apparatus of claim 3 further characterized in that an adjustable stop is provided for determining the position at which the toggle is stopped when moved under influence of said biasing means.

5. In a device having an adhesive impression roll and a presser roll positioned to operate in rolling contact, and means for feeding pre-cut sheets serially in spaced relation for movement between said rolls for applying adhesive to selected portions thereof, the improvement comprising means mounting said rolls for relative movement toward and away from each other, said rolls in one position being in rolling contact against each other and against said sheets when they are moved between said rolls, said rolls in another position being moved relatively out of contact with each other, power means connected to said means mounting said rolls for moving the rolls to said other positions, and sensing means including a first normally operative electrical control rendered inoperative responsive to the movement of sheets toward said rolls, and second electrical control rendered operative responsive to the rotation of one of said rolls, said rst and second electrical controls being connected to said power means for moving the rolls relatively away from each other when no sheet is fed between them by said means for feeding said pre-cut sheets serially in spaced relation, at a time when a sheet should be fed between them.

6. The apparatus of claim 5 further characterized in that said power means is a solenoid, the operative circuit of which is connected through contacts controlled by said trst electrical control and said second electrical control.

7. In a device having an adhesive impression roll and a presser roll positioned to operate in rolling contact, and means for feeding pre-cut sheets serially in spaced relation for movement between said rolls for applying adhesive to selected portions thereof, the improvement comprising means mounting said rolls for relative movement toward and away from each other, said rolls in one position being in rolling contact against each other and against said sheets when they are moved between said rolls, said rolls in another position being moved relatively out of contact with each other, power means connected to said means mounting said rolls for moving the rolls to one of said positions, and sensing means including a light source and photoelectric cell positioned for casting a beam of light across the path of movement of said pre-cut sheets as fed by said means for feeding sheets, and cam operated switch means on one of said rolls, said photoelectric cell and switch means being connected to said power means for moving the rolls away from each other relatively when no sheet is fed between them by said means for feeding said pre-cut sheet serially in spaced relation at a time when a sheet should be fed between them for applying adhesive thereto.

8. In a device having an adhesive impression roll, a presser roll positioned to operate in rolling contact, and means for feeding pre-cut sheets serially in spaced relation for movement between said rolls for applying adhesive to selected portions thereof, the improvement comprising means mounting said rolls for relative movement toward and away from each other, said rolls in one position being in rolling contact against each other and against said sheets when they are moved between the rolls, said rolls in another position being moved relatively out of contact with each other, power means connected to said means mounting said rolls for moving the rolls to one of said positions, and sensing means including a. light source and photoelectric cell positioned for casting :a beam of light across the path of movement of said precut sheets as fed by said means for feeding sheets, an amplitier actuated by said photoelectric cell, and cam operated switch means on one of said rolls, said photoelectric cell, amplifier and switch means being connected to 9 said power means for moving the rolls away from each References Cited in the le of this patent other relatively when no sheet is fed between them by said UNITED STATES PATENTS means for feeding said precut sheet serially in spaced rel lation at a time when a sheet should be fed between them 1,848,138 Novick Mar. 8, 1932 for applying adhesive thereto. 5 2,000,325 Ford et al. May 7, 1935 9. The apparatus of claim 8 further characterized in 2,027,523 Erbe Ian. 14, 1936 that said amplier operates a relay for controlling said 2,167,430 Booty et al July 25, 1939 2,614,522 Snyder Oct. 21, 1952 power means.

10. The apparatus of claim 8 further characterized in that said cam operated switch regulates the operation 10 of a relay for controlling said power means.

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