US2627406A

US2627406A - Sheet-mounting machine

Info

Publication number: US2627406A
Application number: US215586A
Authority: US
Inventors: Mestre Luis
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-03-14
Filing date: 1951-03-14
Publication date: 1953-02-03
Anticipated expiration: 1970-02-03

Description

Feb. 3, 1953 MEsTRE 2,627,406

SHEET-MOUNTING MACHINE Filed March 14, 1951 7 Sheets-Sheet 3 INVENTOR. Lu/s MES TRE H TTORNEY Feb. 3, 1953 L, MESTRE 2,627,406

SHEET-MOUNTING MACHINE Filed March 14, 1951 '7 Sheets-Sheet 4 F; E-H.

INVENTOR. Lu/s MESTRE k =77 TORNEY L. MESTRE SHEET-MOUNTING MACHINE Feb.- 3, 1953 "7 Sheets-Sheet 5 Filed March 14, 1951 INVENTOR. Lu/s MES RE BY Q mew mmq

MFYTTORNEY Feb. 3, 1953 MESTREI SHEET-MOUNTING MACHINE 7 Sheets-Sheet 7 Filed March 14, 1951 INVENTOR. Lu/s MEsTRE fiwk? m A. HTTORNEY Patented Feb. 3, 1953 UNITED STATES PATENT OFFICE SHEET-MOUNTING MACHINE Luis Mestre, New York, N. Y.

Application March 14, 1951, Serial No. 215,586

25 Claims. 1

The present invention relates to sheet-mounting means, for example means for applying sheets of material to backing sheets and more particularly to means for superimposing sheets of material on sheets already attached to backing sheets and securing each sheet so super imposed to the corresponding backing.

An important object of the invention is to provide novel and advantageous means of the general character specified.

Another object of the invention is to provide apparatus of the general character specified wherein sheets of material to be attached successively to units comprising backing sheets are formed by intermittently drawing suitable lengths of material from a roll and severing the same to form said sheets, and the sheets thus formed are advanced intermittently to a position where they are to be secured to the corresponding backing sheets.

Still another object of the invention is to provide apparatus of the general character specified wherein sheets of material to be mounted successively on units comprising backing sheets are intermittently fed lengthwise to a position for such attachment, and said backing sheets facing downwardly have adhesive applied to the upper ends of their faces, and are fed one by one to the attaching position over corresponding mounting sheets where each unit is supported until properly positioned and is then dropped on the corresponding mounting sheet and pressed thereagainst along the position of the adhesive.

Yet another object of the invention is to provide apparatus of the general character specified wherein each sheet to be mounted and a corresponding unit of a plurality of downturned units comprising backing sheets and attached sheets, are brought together at an attaching position with each unit on top of a sheet and secured together at the head end of the backing sheet, and the assembly is advanced from the attaching position and turned downwardly and rearwardly to bring the sheet thus mounted into top position.

A further object of the invention is to provide apparatus of the general character specified wherein with a pile of units comprising downturned backing sheets with thin sheets attached to the faces thereof, each backing sheet is picked up at its head end, advanced with said head end forward to a position opposite an attaching position, is then moved sidewise and after application of adhesive to the upper end of its d-ownturned face is positioned on releasable supporting means immediately above said attaching position, is dropped on a thin sheet at the attaching position, and the elements are pressed together to render the adhesive effective.

A still further object of the invention is to provide apparatus of the general character specified wherein a sheet of dielectric material is fed from a roll to a belt of magnetic material and provision is made to produce static electricity on said sheet to hold the same against the belt.

According to one of its applications, the invention relates more particularly to the application of a protective sheet over a stencil sheet mounted on a backing sheet. The protective sheet may be of suitable material, such as Pliofilm. The Pliofilm is drawn from a roll and placed on a conveyor belt of magnetic material by which it is carried to a position for attachment to a backing sheet carrying, for example,

a stencil sheet. As the Pliofilm is intermittently advanced by the conveyor, it is severed at regular intervals by suitable means to form sheets of the proper size to be attached to the backing sheets. The Pliofilm both before and after severing is held on the belt by a staticelectricity-producing device which normally is close to the belt but is withdrawn each time the sheet is severed to provide an additional sheet of Pliofilm.

The backing sheets with the attached stencil sheets are supplied in a pile face down. By means of a suitable device each backing sheet is picked up at its head end and placed on a conveyor so that the stencil sheet is held between the conveyor and the backing. Each backing sheet is advanced to the attaching position so as to arrive there substantially at the same time as a Pliofilm sheet and on its way is provided with adhesive material at the head end of its face.

At said attaching position the backing sheet is positioned over the Pliofilm sheet and with the stencil sheet attached thereto is held directly above the Pliofilm sheet and then is dropped into position on the Pliofilm. As soon as this arrangement is completed pressure is applied to press the backing sheet and Pliofilm sheet together so as to render the adhesive means efiective. As soon as this attachment of the Pliofilm sheet to the backing sheet is completed, the assembly is fed forward and turned over so that the stencil sheet and Pliofilm sheet are on top of the backing. The assemblies of sheets are then conveyed to any suitable position in such a manner as to have the sheet assemblies pile up on each other.

To produce the desired result in bringing the backing sheets carrying stencil sheets into position over the Pliofilm sheets, the pile of stencil sheets and backings is so arranged that when the backing sheets are picked up at their upper ends they are conveyed forwardly in a direction parallel to the feed path of the Pliofilm sheets. When each backing sheet with attached stencil sheet reaches a position even with the assembling position it is fed sidewise toward the attaching position and during this movement the head of the backing sheet passes through a device which applies adhesive to the head of the backing. sheet in position for engagement with the endof the corresponding Pliofilm sheet.

As the backing sheet with attached stencil sheet reaches the assembling position it is deposited on fingers which are inserted from the opposite sides of the assembling position along lines corresponding to the movement of the backing sheet. These fingers act to support a backing sheet with attached stencil sheet during positioning of the same over the Pliofilm sheet. As soon as this positioning is completed, the fingers are withdrawn to drop the backing sheet and attached' stencil upon the Pliofilm sheet, and the backing sheet'and Pliofilm sheet are pressed together along the line of adhesive. These operations are repeated and the resulting assemblies are piled up as long as the supply of material is exhausted or the machine is stopped manually.

Other objects, features and advantages will appear upon consideration of the following detailed description and of the drawings, in which Fig. 1 is a front elevation of the left hand of a machine embodying the present invention, certain parts being omitted;

Fig. l-A is a front elevation of the right hand end of the machine and a part of the structure shown in Fig. 1, certain parts bein omitted;

Fig. 2' is a top plan view of the left end of the apparatus corresponding to that shown in Fig. 1;

Fig. 2-A is a top plan view of the right hand end of the machine corresponding to the part shown in Fig. I-A;

Fig. 3 is an end elevation of the machine as seen from the left of, Fig. 1, parts being broken away to show the underlying structure;

Fig. 4 is a fragmentary view on a larger scale showing mechanism as viewed from the right at the center of Fig. 2;

Fig; 5 is a fragmentary view illustrating a straightening roller and a mounting therefor arranged to act on the continuous band before it reaches the cutting device;

Fig. 6 is a detailed view partly in section showing a device for regulating the position of the straightening roller of Fig. 5;

Fig. '7 is a fragmentary View partly in section illustrating the means for cutting the continuous strip;

Fig. 8 is a fragmentary view illustrating the manner of applying adhesive tothe backing sheets;

Fig. 9'is a fragmentary view showing a backing sheet with the usual key-hole slots and with dots of adhesive alternating therewith;

Fig. 10 is a fragmentary sectional view illustrating a backing sheet resting on supporting fingers and a holding device located above the same;

Fig. 11 is a sectional view taken on the line Hll of Fig. 10;

Fig. 12 is a view corresponding to Fig. 10 but with the supporting fingers withdrawn and the holding device resting on a backing sheet;

Fig. 13 is a sectional view taken on the line !3l3 of Fig. 12;

Fig. 14 is a view corresponding to Fig. 9 but with a sheet severed from the continuous strip, attached by adhesive to the head of a backing sheet;

Fig. 15 is a section on line l5i 5 of Fig. 3; and

Fig. 16 is a section on line l$lfi of Fig. 15.

Referring to Figs. 1, l-A, 2 and 2-A, suitable material 2% such as Pliofilm is drawn intermittently from a roll 2i and fed to a conveyor belt 22 of metal link construction having at its edges sprocket chains 23. At its receiving end said belt 22 is mounted on sprocket wheels 26 which are fixed on a shaft 25 and cooperate with said sprocket chains 23. At the discharge end of said conveyor belt 22, the sprocket chains 23 at the sides of the belt are mounted on sprocket Wheels 23 fixed on a shaft 2?.

During the intermittent advance of Pliofilm on the conveyor belt, successive individual sheets 28 are cut from the leading end of the continuous sheet 29 of Pliofilm by cutting means indicated generally by Ed in Fig. 1 and operating through transverse slots 22 (Figs. 2 and 7) at regularintervals along the belt. As the operation of the machine continues individual sheets 28 are advanced one by one on said conveyor belt 22 to a final position at which a unit 3! comprising a downwardly facing backing sheet or backing 32 (Fig. 9) with a stencil sheet 33 attached is dropped thereon and secured thereto by adhesive previously applied to the head of the backing sheet 32 in spots 3 Concomitantly with the operation of advancing the continuous sheet 25, cutting off individual sheets 28 and advancing them one by one to said attaching position, downwardly facing units 3!, arranged in a pile on a table 35 with their head ends to the left, are picked up one by one and shifted to the left to conveying means 38 which advances them one by one to a transfer position opposite the attaching position on conveyor belt 22.

After reaching said transfer position, each unit 3! is shifted sidewise, supplied with spots 34 of adhesive, and finally after reaching a position over a corresponding Pliofilm sheet 28 is dropped on saidsheet and secured thereto by pressure along the line of spots 34. The assembly thus formed is advanced from the attaching position and due to bands 38 is carried down around the end of the conveyor belt 22 and dropped face up on a conveyor 3? which carries it to a discharge position practically below said Pli-ofilm roll 2!.

The machine as disclosed in Figs. 1, l-A, 2 and 2-A is of general U-shape and for convenience the lower part on Figs. 2 and Z-A will be referred to as the front part of themachine, the upper part of these figures will be referred to as the back part of the machine, and the left hand part will be called the connecting. part.

Power for driving the machine is provided by an electric motor 49, a pulley 4i driven by said motor, and a large pulley 42 driven from pulley ll by means of a belt 43. Said pulley i2 is mounted on a shaft 3 5 which at the rear of the front part of the machine carries a small sprocket wheel 45 connected in' turn by means of a sprocket chain 46 to a sprocket wheel 41 fixed to a shaft 48.

A disk 49 is fixed on the forward end of shaft 48 and from the front face of said disk 49 a pin 49' projects through a slot 59 in the upper part of a lever with its lower end mounted on a pivot 52 carried by a side-frame member 53 of the main frame. Connected by a pivot 54 to the upper end of lever 5| is a bar 55, extending to the left and provided at its left end with a downwardly facing rack 56 meshing with a pinion 51 loosely mounted on shaft 21. Said pinion 51 is connected to shaft 21 through a one-way clutch 58 arranged for use in turning shaft 21 intermittently in counterclockwise direction by leftward movement of the bar 55. It will be understood that rightward movement of bar 55 will be an idle movement. The intermittent advance movement of shaft 21 causes an intermittent advance of the upper reach of conveyor belt 22.

Extending to the right from the upper end of lever 5| is a bar 59 pivotally connected to said lever and having at its right end a downwardly facing rack 69 meshing with a pinion 6| on shaft 62 carrying a driving roller 63 (Fig. 2-A) for the Pliofilm, This pinion 6| is connected to shaft -62 by a one-way clutch 64 similar to clutch 58 at the far end of the conveyor belt 22. Leftward movement of arm 5| will therefore operate in a feeding direction both the conveyor belt 22 and the Pliofilm feeding roller 83 (Fig. 2-A). connection between the bar 59 and the lever 5| comprises a pivot 64 and means for securing said pivot at different positions along a longitudinal slot 65 in bar 59, so as to regulate the stroke of said bar 59.

A roller 66 acts to press the Pliofilm 20 against the driving roller 93. As shown in Figs. l-A and 2-A, a shaft 61 carrying the roller 86 is mounted on the forward ends of arms 88 pivoted on a cross rod or shaft 69 and extending rearwardly beneath a shaft 19 having a flat side 1| which when facing down enables roller 68 to rest on roller 63. However, if shaft 19 is turned by hand wheel 12 to bring the round part down, roller 85 will be raised from roller 63.

Mounted on shaft 62 at its rear end is a sprocket wheel 15 connected by a sprocket chain 16 with a sprocket wheel 11 on a shaft 18 rotatably mounted on the rear upright 19 of two uprights 19 on opposite side frames of the Pliofilm-feeding part of the machine. Said shaft 18 is also pro vided with a gear 89 which meshes with the left of two gears 8| carried by a rock frame 82 pivoted to turn about the axis of shaft 18. Said gears 8| are in mesh so as to turn in opposite directions.

As illustrated in Fig. 1-A left gear 8| not only is 'in permanent mesh with gear 89 but is temporarily in mesh with a gear 83 on a shaft 84. By shifting the frame 82 counterclockwise, left hand gear 8| will be withdrawn from gear 83 and the right hand gear 8| will mesh with gear 83 thus reversing the drive. As shown in Figs. l-A and 2-A, shaft 84 may be connected by means of

sprocket wheels

85 and 88 and a sprocket chain 81 to a shaft 98 mounted in the upper ends of uprights 19. A frame or plate 89 is pivotally mounted at one end on shaft 88 bymeans of.

brackets 99 and extends over roll 2| and at its other end and lower side is provided with a shaft 9| parallel to shaft 88. Shaft 9| is driven by means of a sprocket chain 92 connecting a sprocket wheel 93 on shaft 88 to a sprocket wheel 94 on shaft 9|. At a location midway between the ends of roll 2'| of Pliofilm said shaft 9| is The 6 provided with a feed roller 95 (Fig. Z-A) which normally rests on roll 2| and serves to turn the same in an unwinding direction. Said plate 89 is provided with a cutout 96 at the location of the feed roller 95. The strip of Pliofilm from the roll 2| passes over an idler roller 98 on a fixed axis,

under a tensioning roller 91 and over an idler roller 98 near the upper ends of uprights 19. From the roller 98 the Pliofilm strip 29 passes downwardly under a guide roller 99 and beneath the same to drawing rolls 63 and 66.

The tensioning roller 91 controls tension of the sheet 29 and in order to regulate the tension exerted by roller 91, shaft parts at the ends of said roller 91 are mounted in arms I09 pivoted at |9| in the sides of the frame and the downward pressure of roller 91 may be regulated by adjustment of a weight I92 along a member I93 connected to said arms I99 to counterbalance part of said downward pressure.

During a leftward movement of lever 5| Pliofilm 29 will be supplied to belt 22 and the belt will be advanced and carry forward Pliofilm placed thereon. One-half turn counterclockwise of gear 41 will throw arm 5| to the leftward limit of its movement. The forward movement of the continuous sheet or strip 29 will then stop and a sheet 28 of suitable length will be severed or cut off.

This severing action may be effected as indicated in Figs. 1, 2 and 7. Two parallel plates I95 are secured at their lower ends to the frame at opposite sides of belt 22. A shaft I96 is pivoted in said plates I95 near their rearward edges and fixed on said shaft near opposite ends thereof are arms I91 connected pivotally at I98 with a plate I99 carrying an upper knife I I9. Projecting upwardly from the central part of plate I 99 is a fork I99 provided with a pin or pivot ||I extending through a longitudinal slot H2 in one end of an arm H8 fixed at its other end on a shaft ||4 pivoted at opposite ends in said plates I95. Springs ||5 connect pin III to shaft H4 and draw said pin I|| toward the inner end of said slot H2 thus permitting the knife III) to be forced to the right by a lower knife I Hi while maintaining an effective cutting engagement.

Said knife H5 is beneath the upper reach of belt 22 and fixed on a plate ||1 carried by arms I|8 fixed on a shaft I I9 pivotally mounted at opposite ends in said plates I95. Fixed on said shaft I I9 at the outside of the front plate I95 is a short arm I29 provided with a follower I2! which rests on a low part of the top of a generally upright cam I22 pivoted at its lower end at I23 on the main frame. In its ordinary or normal position a swing of the cam I22 to the left will lift the follower I 2| to a dwell portion of the cam and swing blade 98 upwardly. This movement of cam I22 will start downward movement of blade H9 and further movement of the cam will leave the lower knife ||6 stationary while the downward movement of blade H9 is completed. It should be noted that the edge of the lower blade H8 is horizontal and that the edge of the upper knife 9 is inclined so as to facilitate cutting.

Fixed to shaft I95 which operates the upper knife H9 is a downwardly extending operating arm I24 pivoted to the rear end of an operating link 25. The forward end of link I25 is pivoted at I28 to the upper arm of a lever I21 pivoted in turn on the main frame by a pivot I28. A link I29 is pivoted to the lower end of lever I21 at I39 and also to cam |22 which has a low dwell.

portion on which the, follower I:2.I normally rests and a high dwell portion which determines the raised position of knife lit for cutting purposes.

Operation of lever I21 for cutting may be eifected by a link I35 pivoted at its rear end to lever I2? at I36 between the pivots I28 and I33. At its forward end link i35 is provided with a longitudinal slot i3? which receives a pin I38 at the upper end of a generally upright lever I39 pivoted on the main frame at lit and provided at its lower end with a follower MI in a cam groove I 22 onv the back of disk 59. The pin I38 is yieldably' held against the right hand end of slot i2! (Fig. 1) by a spring I43 (Fig. 2) connecting pin I38 and pivot 136.

Referring to Fig. 1,. it will be seen that a half rotation of sprocket ii in a counterclockwise direction will advance the belt 22 one step and will also effect a corresponding although somewhat shorter feed of Pliofilm is from roll 2i. A further half rotation of sprocket wheel All will leave the belt 22 at rest but will cause operation of the severing means through a slot 22' in the conveyor belt 22, to cut off a sheet 28 of Plio-film on the belt.

The operation of the cutting means also controls the operation of holding Pliofilm on the conveyor belt 22 by means of static electricity built up on the Pliofilm band or strip it. For this purpose arms I45 are clamped on shaft II!!- and extend rearwardly over a rod M6 supported at its ends in plates m and on which said arms M5 normally rest. Vertical rods I 18 are adjustably secured to the rear ends of said arms I45. Said rods Hi8 carry a transverse electrical element I49 normally close to the Pliofilm on the conveyor belt 22. As the knives cut the film the element I49 is raised and then lowered again, thus varying the charge of static electricity on the Pliofilm and the effect thereof in holding the Pliofilm on the conveyor belt 22.

Said element use is connected by conductors I56 to suitable sources of power and serves to cause the collection of static electricity on the opposite faces of the Pliofilm band 26! in such a manner that the band 2% is attracted by the belt 22 and held in such manner that it will be held on and advanced by belt 22. Said device or element M9 is of a type which has heretofore been used to destroy charges of static electricity on continuous sheets or bands. In the present case, said element M9 is used to establish such electric charges and utilize them in handling the Pliofilm 26 on the belt 22.

Obviously the machine must assemble with great accuracy the elements to be secured together. One requirement involves accurate guiding and support of the upper reach of the conveyor or belt 22. These effects may be attained by guiding and supporting the sprocket chains 23, as by means of fixed upper and lower guide strips we and i 56 respectively, which project into the spaces between the sides of links of the chains 23 (Figs. 3 and This arrangement prevents sidewise movement of the upper reach or stretch of the belt 22 and strength across the belt 22 is provided by transverse rods 55?. Sidewise movement of the Plicfilm 20 on the belt is limited by short upright guides H58 secured to the belt 22 in pairs at suitable intervals.

Suitable lateral adjustment of Pliofilm strip 20 for proper positioning on the belt 22, may be effected byxmeans of an adjustable guiding roller 99 under which the strip 20 is passed to the roller. 63 against which it is held by the roller 6%,

and by means of an adjustable rod I3 I under which the strip 20 passes from

rolls

63 and 66 to the belt 22.

As shown most clearly in Fig. 6, roller 99 is rotatably mounted in frame I62 mounted on a horizontal. pivot I53 carried by a fixed cross bar I64 secured at its ends to the main frame. shown inFigs. 5 and 6 the roller 55 can be tilted to proper position by means of a set screw I65 carried by a member I66 secured to the cross bar I64, and acting on frame IE2. Rod IEiI. is. mounted'to turn about a pivot I6? at right angles thereto and carried by a fixed cross bar I68 and adjusted by means of a set screw I69 carried by said fixed cross bar I68.

Means for supplying to the attaching or mounting position, units each comprising a backing sheet and an attached stencil sheet Units 3I each comprising a backing sheet 32 and a stencil sheet 33, are piled face down on table 35 and between guides I72. This table 35 I is part of a well known feeding apparatus in which the table is slowly lifted automatically step-by-step, as successive units BI are picked up therefrom by a head N3 of an automatic suction device; a rock shaft lid acts to rock head I13 about the axis of shaft lit. The suction appara-' tus may be put into use or out of use by a rock shaft I'i'i extending to the front of the apparatus.

The rocking of the shaft I'M may be effected by means of a link iii? connecting an arm I19 on shaft I14 with an arm I86 fixed on shaft d8.

Said suction head I73 after picking up a unit 3i inserts it between a driving roller I32 and spring-urged rollers I33 cooperating with roller I32 from above. From these rollers each unit 3% is passed to a conveyor 38. Said conveyor 38 comprises continuous bands I65 connecting a roller I86 adjacent to said roller I32, and a roller I81 at the forward end of a table I38 which supports the upper reaches of said bands I85. Each unit on conveyor 38 is pressed against the front band I85 by balls I89 held in position by a device I90 tensioned between fixed brackets I9I.

The rollers I82 and I86 are driven from shaft 44 which projects rearwardly from the front part of the machine. For this purpose a pulley I92 is fixed on shaft 44 and a belt I93 passing around pulley I92 cooperates with pulleys I94 and I95 on shafts I96 and I9? respectively to drive them and rollers I82 and H36 in the same direction as shaft 44. 7

Each unit 3i is thrown rapidly from the bands I85 to the top of a table I98 through which project from below two rollers I39 driven by a chain 2% connecting a sprocket wheel Zfil fixed to roller I87, with sprocket wheels M2 on shafts 263. Said chain 2% is also guided by suitable idlers. Above said table W3 are devices 254 to guide said units 35 over said rollers and resist upward movement thereof. Said devices 204 comprise strip elements 265 over said rollers I99 and fixed at their rear ends over the table I98 and spaced therefrom to admit units 3i one at a time. Beyond the front ends of said rollers each element 205 is secured to bar 266 perpendicular thereto. Said bar 2l6 is fixed with respect to said table I98 but spaced therefrom to permit the passage of'units 3!.

Balls 299 are mounted along a line in each of said members 2535 so as to project downwardly therethrough and exert light pressure on a unit 31 on the. table while at the same time offering substantially no resistance to movement of a unit 3| in different directions. On top of each member 205 there may be mounted another member having holes therein to accommodate said balls 209.

A unit 3| on table I98 may be moved toward the front of the machine by arms 2 I6 projecting upwardly through openings in table I65 and fixed on a shaft 2 mounted on a part of the main frame. A spring 212 attached at one end to a fixed part of the frame and at the other end to an arm 2| 3 on the shaft 2| I, urges the arms to operate. However, such movement is normally prevented by means of a cam 2I5 (Fig, 4) as set forth hereinafter.

Said devices 264, in addition to said strip elements 205, include strips 2|6 parallel to said elements 205 and which are attached at their rear ends to a fixed member 2|! and also to bar 266. Attached to said strips tilt at their lower sides and perpendicular thereto are strips 2 It with upturned ends toward roller I81, in order to receive units 3| beneath the same. Furthermore the movement of units 3| to the left over table I98 is limited by a stop member 2 I 9 which effects proper alignment of units 3| for their passage through the adhesive-applying unit.

Units 3| when moved to the right (Fig. 3) by arms 2 l6, are controlled by overlying flexible strips 2l9' secured to bar 266 and including downwardly to the edge of table I98 to guide the units 3| to the adhesive applying device.

All of the parts of the machine which have not hereinbefore been described, are operated or controlled from a shaft 226 (Figs. 1 and 3) beneath the rear sprocket chain 23 and slightly to the front thereof and just inside the rear edge of the front part of the machine. Said shaft 226 is driven from shaft 44 by a bevel gear 22! fixed on shaft 44 and a bevel gear 222 fixed on shaft 226 (Fig. 1). Fixed on shaft 226 at an intermediate part is a sprocket wheel 223 (Figs. 1 and 3) which is connected by a sprocket chain 224 with a sprocket wheel 225 on a shaft 226 which is rotatably mounted near its ends in brackets 22'].

Said shaft 226 controls the operation of arms 256, the operations of applying adhesive to a backing sheet, and of conveying a unit 3! from the adhesive applying means to a position over the mounting position.

As shown in Fig. 4 shaft 226 is driven in a counterclo kwise direction. to correspond to the movements. of units 35 to the left from table H8. The lower side of an endless sprocket chain 2315 engages the upper part of a sprocket wheel 23E fixed on shaft 226 and is driven to the left. From the sprocket wheel 235 the chain passes under idler sprocket wheels 2232 and 253 and then turns to the right over sprocket wheel 253 and engages the lower sides of

sprocket Wheels

234 and 235 on

shafts

236 and 23? respectively, and turns them in the same direction as shaft 226. From sprocket wheel 235 which is close to sprocket wheel 23f, chain 236 extends upwardly and over

sprocket wheels

236 and 235 fixed on

shafts

246 and 240 which turn in a direction opposite to that of sprocket wheel 26 i. From sprocket wheel 239, sprocket chain 236 passes along the lower part of a sprocket wheel 252 on a shaft 263 which turns in the same direction as sprocket wheel 23 I. From sprocket wheel 242, the sprocket chain 236 passes around an idler sprocket wheel 244 and returns to the top of sprocket wheel 23 i.

Mounted on said shaft 243 at suitable intervals are feed rolls 245 which cooperate for feeding purposes with rolls 246 on shaft 241. Shaft 241 is mounted in arms 248 fixed on a shaft 249 journalled in the brackets 22?. Shaft 249 may be turned to move rolls 246 toward and away from rolls 245 fixed on shaft 243, by means of an arm 256 fixed on shaft 249. Pivoted at its upper end to said arm 256 is an upright link 250' pivotally connected at its lower end to the end of a lever 25! of which the other end is mounted on a pivot 252 carried by the fixed frame. At an intermediate point lever 25! is provided with a follower 253 engaging a cam 254 on a shaft 255 parallel to shaft 226. Shaft 255 is operated counterclockwise or in the same direction as sprocket wheel 23!. Shaft 249 may be urged in a direction to cause rolls 246 to cooperate with feed rolls 2% by means of an arm 256 on shaft 249 and a spring 256 (Fig. 2) connecting this :arm to a fixed part of the machine.

Said cam 254 has a circular-arc high portion 256 extending through more than anda circular-arc low portion 251 which, with connections to cause outward and inward movements of the follower 253, complete the outline of the cam. While said follower 253 rests on said high portion, said rolls 246 are in raised position and are ineffective to cooperate with feed rolls 245 to advance units 3| into the adhesive applying device. However, as soon as said follower is permitted to engage said low portion 251, rolls 246 drop into position to cooperate with feed rolls 245.

Said cam 2l5 is engaged by a follower 266 on a lever 26! mounted at one end on a pivot 262 and connected at the other end by a pivot 263 with a link 254. Link 264 is also connected by a pivot 265 (Fig. 3) to said arm 2H3 which controls the movements of unit-advancing arms 2H]. Cam 2l5 has a circular-arc high portion 266 which, while in engagement with follower 260, holds arms 246 in rearward position. This high portion 2336 occupies about 270 of the circumference. The cam also includes a low portion 261 which occupies the remaining interval. Said low portion is substantially straight and permits, a full forward movement of arms 2 l 6 by spring2 l 2.

As indicated in Figure 4, the cam 254 has just acted on follower 253 to move rolls 246 away from feed rolls 245 and there will be no feeding of units 3| by these rolls until the cam 254 has turned through an angle of over 180. Also cam 285 on the same shaft 255 has just restored the arms 219 to retracted position (Fig. 3) against the tension of spring 2E2 after feeding a unit .3l into the adhesive-applying part of the machine.

As shaft 255 turns in counterclockwise direction, follower 253 will ride down oif said high portion 256 of cam 254 to permit rolls 246 to cooperate with feed rolls 245 and at almost the same time follower 266 will ride off high portion 266 of cam 2E5 and a unit 3! will be fed to

rolls

245 and 246.

From

rolls

245 and 246, each unit 3| passes beneath rolls 2Y6 on shaft 24! and correspondingly positioned rolls 21! or shaft 236 and over rolls 212 on shaft 226 positioned to operate for feeding purposes with all

rolls

210 and 21! except the last roll 276 and the last roll 21! which cooperate with an adhesive-applying member or disk 212' fixed on said shaft 226. Said member 212' is in the general form of a round plate with onehalf thereof provided with cutouts to form four radial fingers 213 positioned to apply to a backing sheet 32 four spots or dots 34 of adhesive alternating with the usual keyhole slots at the head of said backing sheet 32. It shouldbe lun'derstocd that .use may be .made of part submerged in said 7 tovanylbacking sheet 32.

,and carried at their other or acetate backing sheets without keyhole slots or openingsand that the adhesive may be applied in other patterns.

.The ,adhesive in liquid suitable container or pan applying memberZlZ" by a disk 215 with its lower adhesiveand a second disk'izlein edge engagement with disk tile and adhesive-applying member 212'. Said disks 215 and 213 '(Fig. .3) are driven by a sprocket chain fl'lflwithitsupper reach extending over a sprock- ...et wheel12l8 on shaft 2T9 carrying disk 215, a .sprocket wheel 28!! on a shaft 28| carrying disk i216, and asprocket wheel 282 on shaft 223 carry- .inga'dhesive-applying member 212'. The lower reach of sprocket chain 21'! extends from sprocket wheel282 to-sprocket wheeli'l'iii without engaging the sprocket wheel 283.

-A scraper or doctor knife 283 acts to smooth out .the adhesive on roll H5. Alsothe oppositely moving surfaces at positions of transfer from roll 215 to roll '215 and from roll 2'56 to .member 12.12, 'tendto distribute the adhesive to advantage. ,It should be understood that unit 3i is passed over member 2'52 at one revolution there- .of andthat the semi-circular part 2% of member .212 is idle, that is, it does not apply adhesive It would seem that the semicircular part might be omitted. However, it has' been found in. practice that better results are attained when the continuous semicircular .part' 284 is used in that it helps to maintain a more uniform distribution of adhesive enroll 'From rolls 21H on shaft .233 and rolls Eli! on vshaft '225, each unit passes overrolls 22:5 on-shaft 231 vatithe. exit end of the device. During the passage of a unit 3| at this part of the machine, it passes under resilient strips 236 (Fig. 3) atfltached at their rear ends to a cross bar 2877 car- ..rield'by brackets 122i. 'Said strips 28% pass be- .neathsaid shafts 248 and 2M and between disks I210 as well as betweendisks 2'! i.

' .From rolls 28,5 each unit 35 passes to a con- 'veyorJ290 comprising continuous bands 23E driven ibyioneor more rolls 292 on shaft 238 (Fig. 3) advance ends by one or morerolls 233 on shaft 2% mounted on the framed the machine. The bands 2% may be (held under proper tension'by tighteners 235. Over said bands 29| is a :resilient strip 2% which assures .the required pressure of a unit against .theban'ds, for efiective conveying action. Said resilient strip 235i is fastened at its rear end on a shaft 29'! supported in'said bracketsZZl, and

"itsfforward end extends beyond the discharge end gof'the conveyor 290.

. From the conveyor 2% the leading edge 'of the "unit 3| falls uponrods coveringthe mounting position. One setofrods 3% when retracted is located-entirely under conveyor 2% but may be advanced to a location over the mounting position. Another set of rods 33! is located at the ppositeside of the mounting position and may be advanced over said mounting position.

Each rod SM is secured at its rear end to a bar 3302 and at all times extends through a guiding opening 303 (Figs. 3, l and 12) in the upper guiding strip I55 for the sprocket chain 2'5 at the adjacent side of belt 22.

Said bar 332 is fixed to a carriage 3% located centrally thereof and mounted-to run on a track formed of two ;parallel rails 33% arranged in a horizontal plane. Theinner ends of said rails 3% are rigidly contnecteditoza part. of'the: main frame and the outer form is taken from a Z'id and is supplied to an upright bracket .endsof said rails are connected by a plate 396 secured thereto.

"Said-rails 335 are illustrated as round'and said carriage 33 comprises and iscarried by four rollers 3&1 engaging one rail and four other rollers fill-engaging the other rail. Two of the rollers3ll engagingeach rail are on pivots 338 inclined inwardly and downwardly and the other two rollers are inclined inwardly and upwardly.

The resultant effect is that carriage 3352, while easily movable along said rails is heldagainst upward or downward movement, against sidewise movement and against tilting.

Carriage tilt is also provided at its central portion with a fiat-top bar or member 3539 in the same general plane as rods 323i, andabovesaid member 3&3 to cooperate therewith a resilient strip or spring 3253 to yi'eldably grip a unit 3! and assure movement thereof into engagement with two guides E58 projecting upwardly from belt 22. Said spring 3H} is ore-shape (Figs. 3, l9 and 12) with the inner end turned upwardly and an. extension at its outer end for securing it to the carriage 33d.

Said rods 3% are rigidly connected at their rearends to a cross bar Sid and extend through openings in the adjacent guide strip |55. Cross bar 353 is also connected to a carriage 3|! similar'tc carriage 3%. The connection between said cross bar 359' and said carriageis by mean of 3 l 2 thus enabling the carriage 3H and its supporting rails M3 to be positioned at 'a'lower level than carriage "3M and rails 335.

Actuation of carriage fiddle eiiecte'd by means of a lever 3i5. Said lever has a pin and slot connection 326 with the carriage and is pivoted at ,3ll to a ;plate 3&3 near its lower edge, said plate 3h; being secured to two legs 3|9 of the main frame. A spring 3M connected at one end to lever Sid above th upper edge of plate 358 and at one other end to a fixed member urges lever tlfiinwardly. The movement of said lever ,is controlled, however, by a cam 323 engaging a follower 32! on said lever 3|5. Said cam SEQ-is controlled'by a sprocket wheel'322 fixed thereto, cam 321i and sprocket wheel 322 being mounted on plate 3E3 by means of a pivot 323.

The movements of carriage 3H are controlled by a lever 32 5 having a pin-and-slot connection with carriage 3H andpivoted at 3525 to plate 3i8. A spring 326 connected to lever 32!; above pivot 325 and to a part fixed to the main frame urges lever 324 to the right. Movement of lever 32 under the action of spring 325 is controlled by means of a link 32?! pivoted at 328 to the lower end o'f'lever 32d and at 329 above follower 32! to lever 3 i 5.

Each unit 3| as it passes from conveyor 290 to the mounting position over the upper reach of conveyor 22, is adjusted lengthwise between a positioning device 3353 having inclined portions for engagement with the bottom end of the unit to assure engagement of the head end of the backing sheet with a device for positioning the head end of the backing sheet. The head end positioning means comprises a vertical plate 33| adjustable longitudinally of belt 22 by screw and slot connections 332 (Fig. 2) between horizontal portions of supporting brackets 333 and a fixed member 334 (Fig. 2). Proper positioning of the lower edge of said plate 33| above the upper reach of belt 22 may be attained by screw and slot connections 33% between said plate 33| and vertical portions of brackets 333 (Fig. 3). Positioning device 330 should also be adjustable 13 and this result is attained by screw and slot connections 335 with a fixed member 336 (Fig 2).

As the rods and 30] are retracted to drop a unit 31 on a sheet 28 on the belt 22, a device 346 moves down to position the unit 3| against the sheet 23 and then to press the unit 3| back of the adhesive material thereon, thus securing the sheet 23 to the backing sheet 32 of the unit 3| by means of the adhesive previously applied. Said device 346 comprises a vertically movable frame 34l over the discharge end of the mounting position. At its bottom frame 34I is provided a pressing device or pad 342 of yieldable resilient material such as sponge rubber (Figs. 1, 11 and 13).

A support or rod 343 is hinged at one end to frame 34! in such manner that it will normally extend over the mounting position. A light pressing member or strip 344 extends across said mounting position perpendicular to said rod 343 and is suspended centrally therefrom by a vertical rod 345 fixed to member 344 and movable upwardl and downwardly through an opening in said rod 343. Said rod 345 although movable axially through said rod 343 is held against turning as by having a square section fitting in a corresponding opening in rod 343. Another pressing member 344 is arranged in the same way beyond the center of said mounting position. Said rod 345 is provided with a head of suflicient size to enable said rods to be lifted by said rod 343.

Lowering of frame 34! brings pressing members 344 into contact with the backing sheet 32 (Figs. 12 and 13) Upon further downward movement of frame 34L the bar 343 will move downwardly, along said vertical rods 345 without increasing the pressure of pressing members 344 on the backing sheet. Meanwhile pad 342 strips the head end of the backing sheet from guide or gauge 33! in the form of a vertical plate and finally presses the backing sheet against the sheet 28 along the line where adhesive had previously been applied.

The operation of frame MI is based upon an arrangement which will now be described. The side edges of frame 34] are provided with rolls 346 which travel in grooves of fixed vertical sides of a frame 341 fixed to the main frame. Short links 343 are mounted at their upper ends on pivots 349 projecting inwardly from the sides of frame 34! and at their lower ends on a rod 353. Said rod 353 is mounted in the ends of arms 350 extending away from the mounting position in a generally horizontal direction to a shaft 35| to which they are fixed. Said shaft 35l is mounted in the extended sides of the frame in which belt 22 is mounted.

Said shaft 35| is rocked by means of a downwardly extending arm 352 fixed thereon, a downwardly and rearwardly extending link 353 pivoted at its upper end to the lower end of said arm, a downwardly and forwardly extending lever 354 fulcrumed near its middle on a pivot 355 and pivoted at its upper end to the lower end of link 353, a follower 356 on said lever 354 and cam 35! mounted on a pivot 35B carried by a post of the main frame.

Cam 351 is secured to sprocket wheel 366 which is drive nby a sprocket chain 36l from a sprocket wheel 362 on a shaft 363 (Figs. 1 and 3). Shaft 363 has fixed thereon a bevel gear 364 meshing with bevel gear 365 fixed on shaft 220.

Means for discharging sheet assemblies from the machine After a Pliofilm sheet has been attached by adhesive to a backing sheet 32 having an attached stencil sheet 33 the sheet assembly 3! thus formed is advanced by the next movement of belt 22 between said belt 22 and said bands 36 which bend the assembly 3| downwardly and rearwardly so that the next advance movement of the belt will discharge the assemblage 3| face up on conveyor 31.

In order for said bands 36 to press assemblages 3! against the belt 22 as it moves around sprocket wheels 26, said bands 36 are guided by corresponding idlers 31! above the top level of sprocket wheels 26, idlers 312 below the bottom level of sprocket wheels 26, and idlers 313 to hold the outer stretches of bands 36 away from the inner ones between the idlers 3H and 312. Idlers 3' are carried by a shaft 314 mounted in brackets 315 mounted on the main frame. Idlers 312 are carried by a shaft 316 mounted in brackets 311. tighteners and are pivotally mounted between the arms 318 pivotally mounted on a shaft 3'19 for individual movement. Each of said frames 318 is urged outwardly from the downwardly curved belt 22 by springs 380, each connected at one end to arm 318 and at the other end to an adjustable member 380'.

Said conveyor 31 comprises a plurality of bands 31' passing around a roller 38I at the left of the machine (Fig. 1) and one or more rollers 382 on shaft 383 at the right of the machine (Fig. 1A). One or more arms 384 fixed on shaft 385 carry rollers 333 which press down on finished assemblies 31 leaving the machine and tend to hold a complete assembly in horizontal position as it is discharged from conveyor 31.

Said roller 333i is fixed on a shaft 390 pivotally mounted on the main frame. This shaft 390 drives conveyor 31 and is driven from said shaft 363 by means of a sprocket wheel 39! on shaft 363, a sprocket wheel 392 on shaft 390 and a sprocket chain 333 connecting these sprocket wheels.

Operation Assume the machine to be running, a roll 2| of Pliofilm 20 to be properly installed in the machine (Figs. 1A and 2A) and a pile of backing sheets 32 with attached stencil sheets arranged face down on table 35. The operation is substantially as follows: The Pliofilrn band 20 is fed from the roll 2! at uniform speed because of the frictional surface drive of roll 2| by positively driven roller 35. If there is too much slack in the loop of strip 23 around roll Ell, the [drive of roll 2! can be reversed by shifting rock frame 82 to bring right hand gear 8! (Fig. 1A) into mesh with gear 83.

Feed roll 63 is operated counterclockwise each leftward movement of bar 53 and in cooperation with roll 66 supported thereby feeds the Pliofilm strip a corresponding distance and supplies it to the upper reach of metal conveyor belt 22. The Pliofilm strip 23 is adjusted from side to side by an adjustable guide roller 39 at the receiving side of roller 63 and mounted in a frame i62 pivoted at I63 on bar I64. Adjustment of said guide roller 93 is effected by shifting frame I62 by means of a set screw 165. At the discharge side of roller 63 there is a guide rod l6! adjustable in the same general manner as guide roller 99. Leftward movement of bar 59 is accom- Idlers 313 are parts of band while on the belt 22.

I -feed-ofconveyo-rbelt2'22 issomewhat faster than that of 1'011552 and "55, each sheet 2% when sev- 'ered is separated by a distinct space from the leading end of the continuous strip. shown in Fig. '7, the static electricity device he comes less effective as'the cutting or severing device-i operated.

sets of rods Still and Bill.

7 paniediiby zleftwai'd'imovement of :bar :55ito advance conveyonb'eltfifi one step.

No mechanical means is used to hold strip 253 on belt '22 for movement therewith, but static electric charges are utilized for this purpose. *Suchchargesare obtained'by means of a static- ;pro'duc'ing device is? which is actually of the same construction as a known form of static eliminatorbut is connected in such a way as'to produce static on the Pllofilm strip Fit. The electrostatic charges tend not only to enable feeding of the strip but also to smooth the Pliofihn Due to the fact that the As best After-a Pliofilm sheet 28 has been severed,

another feed motion of the belt 22 carries the sheet-to the mounting position where a downwardly facing backing sheet 32 with attached stencil sheet is placed over the mounting position "almost simultaneously with the arrival of sheet 28.

In bringing a unit 3! comprising a backing sheet 32 and a stencil sheet 33 to the mounting position, the unit is picked-up at the proper time from table 35, carried by conveyor bands 285 to a position opposite the mounting position, and advanced by'arms 2m to the adhesive-applying device. The unit 3! is then passed through the adhesive applying device by rolls 2 32 and 2% so that adhesive from the four fingers 213 is applied during one-half turn of rolls 252. Then there would be an idle half turn before the next unit was'inserted.

The reason for advancing a unit 31 head on was-that this step was necessary to keep the stencil sheet flat before changing the direction of movement of the unit. If backing sheets only wereto be supplied to the "mounting position, it would be feasible to pick them up sidewise and feed them directly to the adhesive-applying device.

After leaving the adhesive-applying device, the unit is conveyed directly to the mounting position but supported above the same by the two In moving over these rods the'bottom of the backing sheet, if it engages the positioning device 339, will be pressed away "theref om to place the top of the backing sheet against head-positioning plate 335.

Also the leading lateral edge of the backing sheet will pass under spring Bill which will press it against member Sililso that when rods sec and 3M are retracted the backing sheet 32 will be -movedwith fingers 3M until it engages guides 58 at the opposite side of belt 22.

As soon as the rods see and 3d! are retracted,

the vertically movable frame 3 3! (Fig. 3) will be moved downwardly. The first eiiect will be to place pressing members 3% against the backing sheet in mounting position. Further downward movement oiframe 34! will not affect members 3st in that bar M3 will merely move downwardly oververtical rods 3&5.

However during this downward movement the pad 342 will firststrip the head of the backing sheet from gauge 33!, thus enabling the backing sheet to adjust its position, and then press the :backing sheet againstthe sheet 28 to render :effective the adhesiveonthe backing sheet. The

. frame MI and pad 342 wil1 then be vraisediby camtti' acting through interposed parts.

It should be understoodthat various changes may be rmadeand that certain features maybe used without others, without departing from the true scope-and spirit of theinvention.

What is claimed is:

l. A machine for attaching mounting sheets to backing'sheets, comprising a conveyor belt'operated intermittently toieed mounting sheets to and support them at amounting position, means for intermittently drawing a mounting-sheet length from a continuous roll of material and supplying it to said conveyor belt, means for holding the mounting sheet material on said conveyor belt, means forsevering a mounting sheet from the forward "end of said material while the conveyor is at rest, means for conveying a. downwardly facingibackingsheet laterally to a position over said mounting position, means for applying-adhesiveto the upper part of the face of each backing sheet during such conveying, means forpositioning each backing sheet above said mounting position and dropping the same on a mounting sheet supported bysaid conveyor belt in that position, and means for pressing the two sheets downwardly over said-adhesive on the backing sheetand against said conveyorbelt.

"2. A machine according to claim 1 wherein said conveyor belt is provided at backing-sheet intervals with transverse slots atwhich the severing means works.

3. A machine according to claim lwherein said conveyor belt is provided t backing-"sheet intervals with transverse slots and said severing means comprises'two blades normally'above and below the upper reach-of said belt, a connection between the .upper blade and the lower blade to cause concomitant operationthereof and means to operate said blades.

4. A ,machine according to claim 1 wherein said conveyor belt is provided at backing-sheet intervals with transverse slots to permit the severing therethrough of the mounting-sheet material, and said severing means comprises a blade above the upper reach of saidbelt and another bladebelow the same and blade operating means bringing the'lower blade to a 'fiXed position with its edge horizontal and continuing the downward movement ofthe'upper blade with its edge in inclined position to cooperate with said lower blade.

'5. Amachine according to claim 1 wherein said "conveyor belt is provided at backing sheet intervals with transverse slots and said severing means comprises two blades normally above and below the upper reach of said belt, an operating connection between the upper and lower blades, and

operating means for said .connectioncornprising portion to swing said lever and operate the severing means during the dwell period of the belt.

6. A machine according to claim 1 wherein said conveyor belt is provided at backing-sheet intervals with transverse slots, and said severing means comprises an upper blade normally above the upper reach of said belt and a lower blade normally below said upper reach, supporting ,means-for operatingsaidlower knife comprising 17 a rock shaft and arms connected at one end to said knife and fixed at the other end to said rock -shaft, and an arm fixed at one end to said rock-shaft and having a cam follower at the other end, a cam to operate said cam follower pivotally connected to the machine frame at its lower part and having at its top a low circular arc portion and a high circular arc portion to act through said cam follower and hold the lower blade in definite raised position for the severing operation and means to operate said upper knife to cooperate with said lower knife.

7. A machine according to claim 1 wherein said conveyor belt is provided with transverse slots at backing sheet intervals; and there is a driving shaft for said belt at its discharge end, a pinion on said shaft and a oneway driving clutch between said pinion and said shaft; said means for drawing sheet-lengths from said roll of material comprises a drawing roll, a driving shaft for said drawing roll, a pinion on the shaft and a one-way clutch between the pinion and the shaft; and the means for intermittent operation of said belt and drawing roll comprises racks meshing with said pinions, an operating member connected to both of said racks, and means for oscillating said operating member.

8. A machine according to claim 1 wherein said conveyor belt is provided with transverse slots at backing sheet intervals; conveyor-belt-driving means comprises a driving shaft at its discharge end of said belt, a pinion on said shaft and a one-way driving clutch between said pinion and said shaft; said means for drawing sheet-lengths from said roll of material comprises a drawing roll, a driving shaft for said drawing roll, a pinion on the shaft and a one-way clutch between the pinion and the shaft; and the means for intermittent operation of said belt and drawing roll comprises racks meshing with said pinions, an operating lever connected to both of said racks and having a longitudinal slot, and means for oscillating said operating lever comprising an operating shaft and a crank pin carried by said shaft and extending through said slot.

9. A machine according to claim 1 wherein said conveyor belt is provided with transverse slots at backing sheet intervals; the belt-driving means comprise a driving shaft at the discharge end of said belt, a pinion on said shaft and a one-way driving clutc'h between said pinion and said shaft; said means for drawing sheet-lengths from said roll of material comprises a drawing roll, a driving shaft for said drawing roll, a pinion on the shaft and a one-way clutch between the pinion and the shaft; the means for intermittent operation of said belt and drawing roll comprises racks meshing with said pinions, an operating member connected to both of said racks, and means for oscillating said operating member comprising an operating shaft; and the means for operating said severing means comprises a lever pivoted at an intermediate point and having a cam follower at one end, a connection between the other end of said lever and said severing means, and a cam on said operating shaft having a cam groove for said cam follower, said cam groove having a circular arc dwell portion to hold the severing means out of action during advance of the belt and an operating part to render the severing means effective while the belt is at rest.

10. A machine for attachin mounting sheets of dielectric material to backing sheets at a mounting pos t o p g a metal conveyor belt extending across said mounting position and having transverse slots at backing-sheet intervals, means for intermittently advancing said conveyor belt through said backing-sheet intervals, means for intermittently advancing to said conveyor belt mounting-sheet lengths of said dielectric material from a roll thereof, a device above the path of said dielectric material on said belt to impart thereto an electrostatic charge to hold it against said belt, severing means beyond said device to separate mounting sheets from the leading end of material from said roll, and means for attaching to each of said mounting sheets while in saidmounting position a downwardly facing backing sheet having adhesive thereon, by pressing said sheets against said metal conveyor belt.

11. A machine according to claim 10 comprising means for operating the belt advancing means and the advancing means for mounting sheet lengths are operated during the same time period but the latter at a lower speed than the belt-advancing means so as to produce spaces between successive sheets.

12. A machine for mounting at a mounting position mounting sheets on backing sheets comprising means includin a conveyor belt to feed mounting sheets one by one to and beyond said mounting position, means for feeding backing sheets laterally one by one face down to said mounting position, means for applying adhesive to the face of the head end of each backing sheet during such feeding action, means to position each backing sheet on a mounting sheet at the mounting position and means to press together the backing sheet and the mounting sheet of each pair at said mounting position to render the adhesive effective.

13. A machine according to claim 12 wherein the adhesive applying means comprises two rotatable rolls to engage from above the back of the head end of a backing sheet passing through the adhesive applying means and a rotatable adhesive applying disk against which said rolls press the backing sheet during a half turn of the disk leaving half of its circumference idle.

14. A machine according to claim 13 wherein there is an additional disk rotatable in the opposite direction to apply adhesive to said adhesiveapplying disk.

15. A machine according to claim 14 wherein there is a second additional disk rotatable in a direction opposite to that of the first additional disk to distribute adhesive on the first additional disk, and a receptacle containing adhesive into which the second additional disk dips.

16. A machine according to claim 12 wherein the adhesive applying means comprises an adhesive-applying disk having adhesive-applying fingers occupying one half of the circumference and the remaining semicircumference is idle, and g elans to press the face of said sheet against said 17. A machine according to claim 12 wherein the adhesive applying means comprises at its receiving side a set of feed rolls fixed on a feed shaft and located to engage from below an advancing backing sheet, means to operate said feed shaft continuously, a set of presser rolls to press a backing sheet against said feed rolls and means to raise said presser rolls to render the feed rolls ineffective.

18. A machine according to claim 12 wherein the means for conveying backing sheets laterally include a table on which the backing sheets are placed one by slots directed means; levers fixed ing upwardly through said slots, spring .means urging the arms in a direction to means, and including a cam to control the posi-. tion' and action of said "arms; the adhesive ap-. plying means including feed rolls above and below the entrance path for backing sheets and means including a cam for separating and bringing together the upper and lower rolls; and a shaft on which both of said cams are fixed.

19. A machine according to claim 12 wherein the backing sheet-positioning means comprisesa gauge to position the head end of the backing sheet and means to engage the foot of the backing sheet and cause the head thereof to engage said head gauge.

20. A machine according to claim 12 wherein the backing-sheet-positioning means comprises two sets of rods movable endwise across the conveyor belt at the mounting position to receive thereon a backing sheet before dropping the same on the mounting sheet at the mounting position on the conveyor belt, and means for moving said rods outwardly.

21. A machine according to claim 12 wherein the backing-sheet-positioning means comprises two sets of rods movable endwise across the conveyor belt at the mounting position to receive thereon 9, backing sheet before dropping the same on the mounting sheet at the mounting position on the conveyor belt, and means for moving said rods outwardly comprising levers connected at their upper ends to said sets of rods, spring-means urgingsaid levers inwardly to move said rods inwardly across the belt, and cammeans to swing said levers.

22. A machine according to claim 12 wherein the backing-sheet-positioning -means comprises guide members arranged at intervals along said belt at opposite sides of the path followed by mounting sheet carried thereby; the means for feeding backing sheets to the mounting position passing the backing sheets over the guidemembers at the adjacent side of the mounting-sheet path, two sets of rods endwise across the conveyor belt from opposite sides thereof and below the top of said guide members, means for advancing said rods and retracting the same to drop a backing sheet on a mounting sheet, and means on the rod-set opposite an advancing backing sheet to draw it against the guide memher at the opposite side of the mounting sheet path comprising a, fiat-top rod and an S-shape spring abovethe same with a'raised endto receive a backing shee'tbeneaththe same and guide it beneath the' bottom of the upwardly concave part'which engage the backing sheet and holds it against the fiat-top rod until it engages the guide member of the row at the oppositeside of the 'mounting sheet path.

'23. A machine for mounting at a, mounting poone, said :table. having parallel; toward the adhesive applyingon a rock shaft and extends;

advance a btCk-. ing sheet on the tableto said adhesiveeapplying.

sition mounting sheets on backing sheets comprisinglmeans including aconveyor belt to feed mounting sheets to and beyond said mounting position, means for feeding backing sheets laterally one by one face down to a position above saidmounting position, means for applying adhesive to the face of the head end of each backing sheet during such feeding action, means operating-to support each sheet above the mounting sheet and then to release the same, a gauge to position the head end of the backing sheet on the supporting means, means to engage the foot of each backing sheet and move the head end against the gauge while the sheet is on said supporting means, and means for attaching the backing sheet to the mounting sheet comprising a 'presser to engage thebacking sheet above the adhesive, strip the head end from said gauge and press the two sheets together.

24. A machine. according to claim 23 wherein the presser carries a rearwardlyextending member, vertical rods loosely mounted, in suitable openings for upward and downward movement without rotation, light presser members extending across said mounting position, said rods having heads to enable them'to be lifted but enabling other light presser members to. fall below the main presser member. r

25. A machine for mounting-at a; mounting position mounting sheets .on backingysheet units each comprising a backing sheetgand an, attached stencil sheet, comprising means including aconveyor belt to feed intermittentlyjmounting sheets one by one to and beyondsaid mounting position, a conveyor for feedingbackingtsheet units to a table opposite said mounting posi-tion,;means for picking up the head: ends of downwardly facing backing sheet. units in alpile with the head ends toward the backing-.sheet-unit.conveyor leading to said table, means: for feeding-hacking sheet units laterallyone by oneiace down from said table to said mounting position, means for ap plying adhesive to. the face .of thehead :end of each backing sheet :during: the last,,mentioned feeding action, means. to position each backing sheet unit on}; mounting sheetat the mounting position and means to press-together the backingsheet and the mounting sheet of each pair torenderthe adhesive effective. LUIS MESTRE.

REFERENCES CETED The" following-references are of record in. the file of this patent:

UNITED S'IATESiPATENTS