US2248255A - Machine for applying and drying adhesive - Google Patents

Description

July 8, 1941. 5G, STAUDE' MACHINE FOR APPLYING AND DRYING ADHESIVE 5 Sheets-Sheet l N 6E h k E II E ym? ATTORNEY- July 8, 1941. E. e. STAUDE MACHINE FOR APPLYING AND DRYING ADHESIVE Original Filed April 9, 1938 3 SheetsSheet 2 E D M Y MQMMO I W UV July 8, 1941. E; ca. STAUDE MACHINE FOR APPLYING AND DRYING ADHESIVE Original Filed April 9, 1938 3 Sheets-Sheet 3 INVENTOR EDWIN GSTHUDE BY /M @114,

ATTORNEY NIHH FIG 6 Patented July 8, 1941 Edwin G. Staude, Minneapolis, Minn.

Original application April 9, 1938, Serial No. 201,045. Divided and this application August 3, 1939, Serial No. 288,102

18 Claims.-

This invention relates to a machine for obtaining high speed drying of adhesive material applied while articles are being consecutively fed at high speed, and is divisional of my application Serial No. 201,045, filed April 9, 1938.

An object is to hasten drying of adhesive applied to articles whilebeing fed toward a delivery point, and to so quickly dry them that it is unnecessary to reduce the speed of the machine. Insofar as I am aware, this object has not been accomplished by those machines which use hot v air applied by fan or oven. The present machine does not use heat, and has, therefore, numerous advantages over those older schemes.

This invention broadly relates to a mechanism for applying adhesive to flat surfaces of articles, including paper blanks and the like, and for quickly drying the adhesive after application.

A valuable application of this invention is in gumming and quickly drying thesealing flaps of open-side or open-end envelopes, but it is understood that the invention is not entirely limited to gumming a particular type of article.

The usual practice is to first feed the envelope blanks in overlapped relation and gum the entire exposed sealing flap surface during feeding, and

later to expose the gummed surfaces to either'gas or electric heat, supplemented by a blast of air from a fan to quickly remove the vapor or moisture from the gum or adhesive. This procedure is quite unsatisfactory for various reasons, among which are: uneven application of the adhesive, poor adhesive ability of the finished article, and/or expensive drying apparatus and slow speed.

It is necessary, in order to obtain even applicadiiferent in bronzing because adsorption is not necessary. In the dusting of powdered adhesive on moist adhesive previously applied, the moisture immediately or quickly penetrates the powder and forms a paste, dry enough so it will not adhere unless re-moistened.

Inventors in the past sought to obtain quick drying by using a varnish sizing upon which they dusted powdered adhesive, such as dextrine flour, with the idea that the powder would adhere to the varnish sizing, which is not soluble in water, and thus avoid the paste condition. The result, however, is that the amount of dextrine flour that adheres to the sizing is so small that upon remoistening and sealing (as when used on the sealing flap of an envelope) the amount of adhesive on the flap is not suflicient to make a secure seal. However, the varnish penetrates the dextrine and is not soluble in water and therefore will not adhere upon re-moistening.

If, in order to cause a greater amount of dextrine flour to adhere to the varnish sizing, more varnish sizing is added, then the dextrine flour will become still more embedded in the varnish, which, after drying, is not soluble in water and therefore is not practical as a sealer.

I have discovered and developed a machine for applying adhesive'to the sealing flaps of envelopes and to other articles, which produces a quality of work quite superior to that obtained in the ordinary manner wherein at least two minutes are required for the adhesive to dry betion of adhesive to the surface of the blank, that the adhesive be of a smooth, even flow consistency. This adhesive has a certain moisture content which must be absorbed by the paper or be evaporated in order to prevent accidental or premature sticking of the gummed surface to another part of the envelope.

I am aware that bronzing machines first print on a sizing consisting of a prepared varnish which is not water soluble, and over this moist surface a bronze powder is dusted. In the bronzing process, however, there was no problem of removing moisture by absorption. It is only'necessary to add a product that is not soluble in Water, and in sufilcient amount to cover up the surface. The actual drying takes several hours. Bronzing powder dusted on varnish sizing" acts quite differently from dextrine flour dusted on a liquid water-soluble adhesive. The problem is fore the sealing fiap'can be folded over onto the envelope and placed in a box without premature accidental sticking.

Objects, features and advantages obtained by the use of my gumming and drying machine are many, some of which are the following:

First.--There are only a few blanks in transit during the gumming and drying operation, instead of more than five hundred in the case of the conventional dryer, so that when obliged to shut down the machine for a few minutes, there will be a loss of only a few blanks, instead of more than five hundred, which under the old I conditions will be spoiled because of over-drying and curling.

Sec0nd.The entire operation herein is accomplished in a linear space of about three feet,

instead of in more than one hundred feet for a conventional machine of equal capacity.

Third.There is no annoyance from use of drying heat, either gas or electric, which I do not require, and which often causes stifling heat in a room in which usually from fifty to more than one hundred machines are operating, especially in hot weather. If the room is air conditioned, it produces a terrific load on the air conditioner, at practically prohibitive expense.

Fourth.This process controls the amount'of adhesive application by varying the amount of the moist adhesive application, without the usual slowing down of the speed as a result of the use of the conventional drying apparatus, whenever heavy adhesive is required on sealing flaps. Fifth.By using an adhesive flour on the outer surface there is no worry about the adhesive being overcooked, thus causing a loss of adhesive qualities. 1 1

Sixth.The adhesive can be applied and dried in one-tenth of a second, instead of requiring one and one-half minutes, as is required when the conventional drying scheme is used.

Seventh.With my process there is no difierence in the drying time, due to changes in humidity. This is important to envelope makers during the moist or rainy season.

Eighth-If the gluten of the adhesive has not been released through cooking, the envelope seal made under my process does not become rancid.

In the conventional schemes rancidlty must be disguised by flavoring. By the use of this invention there is no odor nor obnoxious taste, because of the dry, powdered adhesive application which produces a smooth, satin-like finish and is practically tasteless.

Features of the invention include, separately and in various combinations: The use of a powdered adhesive added to a liquid adhesive in a manner to quickly dry the latter, and obtain a required total amount of adhesive; the rubbing or working of powdered adhesive into wet adhesive; to obtain a smooth and even distribution and mixing of the materials of the adhesive coating; the rubbing in by a movement in the same direction as the direction of travel of the article; the rubbing in by means which travels at a greater .speed than the speed of travel of the article; the

removal of surplus powdered adhesive by the use of mohair or other suitable material; the removal of such surplus by means which travels substantially at right angles to the direction of feed of the article; the removal of surplus by a rapidly traveling means; the removal by means traveling more rapidly than the article being operated upon; the application of powdered material by brushes; the application by brushes between which the material is delivered, one of which brushes rotates in the same direction as the article, and the other of which rotates in an opposite direction and at slightly different speeds for self-cleaning purposes; the application of the powdered adhesive by brushes which are spaced in direction of feed of the article and which contact with each other; the operation of that brush which is forwardmost indirection of the feed so its surface moves in the same direction with the article; the submission of the applied adhesive successively to a plurality of working operations for removal of the surplus; and the removal of surplus from the face of the article opposite to that face to which the powdered adhesive is applied.

In the drawings, I have shown my invention applied to a conventional type of envelope machine in which the open-end envelope blank is fed and the adhesive applied at the properpoint,

and then the various folds, during which operations I apply the gum to the sealing flap in a sufficient amount. and dust on the dextrine or other article.

tion will appear in the description of the drawings, and in said drawings Figure 1 is a plan view illustrating a preferred form of the invention and showing the sequence of the operations and the location of the various devices;

Figure 2 is a side elevation, parts being broken away to more clearly show the construction;

Figure 3 is a vertical transverse section on the line 3-3 of Figure 2;

Figure 4 is a vertical transverse section on the line 4--4 of Figure 2;

Figure 5 is a vertical transverse section on the line 5-5 of Figure 4;

Figure 6 is a vertical transverse section on the line .6-.@ of Figure 2;

Figure 7 is a vertical transverse section on either line '|l or line la-1a of Figure 2;

Figure 8 is a vertical section on the line 8-8 of Figure 2; and

Figure 9 is a plan view of an open-end, center -seam envelope to which the sealing flap gum has been applied, showing the envelope as before the sealing flap is folded preparatory to boxing.

Referring first to Figure 2, numeral 2 desig nates an ordinary feed hopper provided with a feed wheel 3 having a friction feed surface 4, in this instance adapted tofeed one envelope per revolution in timed relation.

In practice this feeder will not be used at this point but will be placed at another point in the machine. The feeder is shown here merely to indicate that the blanks are fed in timed relation to an adhesive-applying mechanism, herein comprising an adhesive-applying wheel 5, a wheel Ii for holding the blank against the adhesive-applying wheel, an adhesive-transfer wheel 1, and flow regulators 8 and 9.

The article or envelope is fed forward by means The lower stretch.

of a pair of belts l0 and II. of the upper belt and the upper stretch of the lower belt co-act to advance the envelope or Any suitable feeding means may be used, depending on the handled.

After receiving the adhesive from the adhesiveapplying wheel 5, the envelope travels past the duster station," which includes (see Figures 4 and 5) a slowly revolving one-eighth inch mesh tubular screen' 12, into the center of one side of which the adhesive dextrine or gum flour is fed from a hopper by a spiral screw l3 through a circular opening 55 of that side. As the screen I2 slowly revolves in the casing l2a. (Figure 5), the dextrine or gum flour is dusted onto brushes or rollers II and i5. One of these rollers travels somewhat faster than the other and assists in combing out 'or equalizing the flow of the gum flour to obtain a more'uniform application or distribution of the dextrine or gum flour in the moist adhesive.

The application of the powdered material by brushes l4 and I5 is not absolutely necessary. The adhesive is sometimes dropped directly upon the blank. There is, therefore, no intention to entirely limit the invention to the use of brushes, although the use of brushes is desirable, and when used they are operated as above set forth.

In practice it is necessary to apply rather a type of article being substantial layer of dextrine or gum flour, for example, a layer at least one-sixteenth of an inch or more in thickness. This layer lies on the surface and absorption by capillary attraction of the moisture is too slow. I therefore provide a pair of squeeze rolls I6 and H. The squeeze roll I! has the same surface speed as the speed of travel of the blank or article and assists in feeding the same. However, if the squeeze roll l6 operating at the same surface speed as the squeeze roll I! is adjusted to engage the dextrine or gum flour (which has now covered the moist adhesive to a depth of one-sixteenth of an inch or more) the dextrine is rolled into a flat cake similar to a stick of gum, and practically all of the dextrine or gum flour is wiped off in cakes toproduce an uneven and useless gum surface. I find, however, that by speeding up the squeeze roll l6 to make its speed greater than that of the speed of travel of the blank, I get a sort of "troweP or "wiping effect and can squeeze in or force the dextrine or gum flour into the moist adhesive without proremoving the surplus dextrine or gum flour can be carried out. The mohair-covered belt I8 is driven by a pulley 21 running over an adjustable idler 28 and around idlers 29 and 30, and over a beater 3|, This beater revolves quite rapidly and vibrates the belt l8 by a series of machine hammer blows, shaking the dust out, which dust drops into a hopper 32. The roller i9 is mounted on a shaft 33 which is driven by a gear 34. A scraper 35 is provided for cleaning the surface of the roller I9.

A screw conveyor 36 is provided in the bottom I of the hopper for carrying the surplus dextrine ducing a caked condition. Moreover, this procedure quickly causes a dry, putty-like paste to appear, which will not stick without re-moisten ing.. This putty-like paste later drys after the envelopes have been boxed, under which conditions the sealing flaps cannot curl.

After the envelope or .articlehas'passed the squeeze rollers I6 and H, the flap is passed under a swiftly traveling belt l8,-preferably having a I surface covered with thick mohair. The blank or article is held against the belt by a roller I9 The roller I9 is adapted to travel in the same direction as that of the envelope blank or article. The mohair-covered belt l8 travels at right angles to the direction of travel of the blank and is adapted to remove the bulk of the surplus dextrine or gum flour. The object in operating the belt in a direction at right angles to the line of feed is to remove the surplus dextrine or gum.

flour out of the path of the traveling article as quickly as possible. Moreover, in order to pass the flap of the envelope or article or material to which adhesive is to be applied, under the belt i8, it is necessary to operate the belt l8 at very high speeds, otherwise the sealing flap on an envelope or article will not pass underneath, because the mohair-covered belt 18 travels at right angles to the direction of travel of the envelope or other article. a

Numeral lBa designates a mohair-covered belt similar to that shown at It. It is somewhat winder and is adapted to remove the final loosedust and polish the surface. In Figure 8, there is shown a mechanism similar to that of Figure '7,

except that the mohair-covered belt arrangement operates on the underside of the blank to completely remove any dextrineor gum flour that may have accumulated on the opposite side of the blank.

The arrangement of the squeeze rolls is shown in Figure 6. Upper and lower belt stretches l0 and H advance the blank or article 20 between the rolls. The lower squeeze roll I! is mounted on a shaft 2| in a .bearing 22, and is driven by a spur gear 23 meshing with a spur gear 24, secured to a shaft 25, operating in a bearing 26, the shaft 25 being secured to the upper squeeze roll IS.

or gum flour back to the intake hopper 31 (Figure 4). This mechanism for moving the dextrine from hopper to hopper is not'shown. The pulley 21 is mounted on a shaft 38 and is driven through a reducing gear mechanism by a high speed motor shown at 39 in Figure 7.

On the underneath wiper, as shown in Figure 8, substantially the same mechanism is used as that on the overhead wiper, and a roller 40 traveling at blank surface speed is used to hold the envelope or other article well against the mohair-covered belt I8. The roller 46 is mounted on a shaft 4|, operating in a bearing 42, and is driven from any suitable source.

To hold the blank up while passing beneath the brushes l4 and I5, there is provided (see Figure 4) a series of narrow rails 43,,having spaces 44 between them to permit the dextrine or gum flour to fall through into the hopper 45 when the blank 20 or,other article is not directly beneath the said brushes l4 and I5. In order to keep the screen clean, there is provided an idler brush 46 (see Figures 4 and 5) mounted on a shaft 41, and revolving loosely in bearings 48 and 49. bristles 50 of this brush enter the openings of the screen mesh and clean same. There is also provided a loose roller 5| or ball to further assist in agitating the material to prevent clogging of.

wall 53 of the screen I2 is providedwith an inwardly directed hub 59 receiving a shaft 60, and held thereon against rotation by the thumb-screw 6|. This shaft 66 telescopes or rotates within the shaft 5'! to provide separate drives respectively for the screen l2 and the spiral screw l3. In practice the pitch of the spiral screw is so constructed that the screen l2 may be attached directly to the shaft 51.

The brushes l4 and I5 are mounted on suitable shafts 62 as provided with bearings 63. The shafts 62 are driven from any suitable source.

The usual supporting rollers 65 are provided. for the upper stretches of the belt I I and the pressure roller 66 for holding down the lower stretches of the belt Ill.

Although repeated reference has been made to dextrine or gum flour, it is \mderstood that any other suitable powdered or granular material may be used which is water-soluble or which is usable for obtaining the proper seal.

It is further understood that the lateral-wiping The scheme may be used for removing surplus materials of other' kinds from fiat articles as they are fed at high speed. The high speed operation of the wipers to draw the surplus, granular or powdered material laterally in a direction at right angles to the line of feed, is considered per se to involve a new conception to obtain new and better results and to involve new ideas of means. The idea or step of polishing the adhesive by the same means and as a result of the same motion is also considered new.

I believe myself the first to provide means for applyingv pressure to the adhesive mix, that is, after the dry adhesive has been added to the wet adhesive, for the purpose herein.

Another feature of the invention relates to the application of the adhesive to a part of the article which projects laterally of the means which feeds or advances it.

Reverting to the wipers l8 and la, it is noted that in this instance the blank is clamped between the belts to hold it against motion while passing under the mohair wiper. The blank should always be held against movement for this purpose, but other means may be used for holding it.

.I have found that powdered adhesive has less tendency to adhere to mohair after the wiping operation than-to any other material thus far experimented with and the powder is more readily thrown off of mohair material by centrifugal force when the wiper l8 starts around the pulley 21 (see Figures '7 and 8) after the powdered adhesive has been loosened by the agitator 31. It is noted that there should be considerable difference in rates of travel between the wiping means and the article. As an example of difference in In the experimental and development work, it was found necessary to hasten absorption of the moisture of the wet adhesive into the dry adhesive by mechanical means, and the best and simplest method I have thus far found is that of pressure applied by motion in direction of the motion of the article and at a greater speed than the article, .to thoroughly impregnate the moist adhesive and iron down the dry adhesive substances to a dry; non-sticky condition, after which it is possible to remove the surplus powder and polish the material to a smooth condition without destroying the finish or otherwise producing an article which is not commercially acceptable, or which will not have the proper adhesive qualities.

Because of the high speed and the turbulence of the powder set up by this high speed action, the article must finally be brushed on both sides so that any surplus may be removed and the article delivered free of the loose, dry, powdered adhesive;

The use of this invention entirely eliminates the long, messy, drying chains of previous machines, which chains are usually to 50 feet in length, and operate in a tunnel, and have to be submitted to a heated blast of air to assist speed it may be said that the speed of the wipers I8 and la should be about six times the speed of travel of the blank. On a machine in which the blank travels at a surface speed of 300 feet per minute, the surface speed of the wipers is about 1800 feet per minute. The surface speed of the wipers must be such that the sealing flap of the blank 20 (traveling at right angles to the wipers) will not "tangle or crinkle against the wipers. To obtain high-speed of the wipers .the motor 39 is used and in this embodiment it runs continuously whether the mechanism is advancing the blanks or not.

Under the process herein I am able to apply and completely dry the gum of a sealing flap of an envelope in one-tenth of a second and while the article travels a distance of approximately thirty inches, at a surface speed of 250 to 300 feet per minute.

The wet adhesive is initially applied and then I apply the powder uniformly to a depth of about three sixty-fourths of an inch and then force the powder into the wet adhesive by a roller, the working surface of which travels at a greater speed than the feeding speed of the envelope or blank, whereby the dry powder is forced into the wet adhesive. 7

In practice I have found that the speed above mentioned is so great that capillary action alone istoo slow, and if depended upon entirely, results in a somewhat unevensurface. It is necessary that the dry materialbe rolled into the wet material to obtain a thick, pasty consistency clear down to the paper. If such a consistency is not obtained, any wiping action will (because of the great feeding speed) quickly remove practically all of the dry adhesive or powder, and produce a commercially unfit product.

drying. Using such chains, even-under the most favorable conditions, requires more than two minutes to dry, if a'sufficient amountof adhesive is applied to the flap so that the final product may have the proper adhesive quality.

The invention not only eliminates this cumbersome chain mechanism and heated air blast, but produces an envelope flap having the desired amount of adhesive to obtain uniform sealing, and this is accomplished so that'the flap may be folded over without sticking, after the blank or envelope has traveled a distance of 30 inches at the high rate of speed mentioned. Thus, the actual time of applying the adhesive and drying the same to a point at which the sealing flap may be folded without sticking is less than one-tenth of a second.

A further advantage of great importance is that, because of the short time required for application, there are never more than three or four envelopes'in the actual process of being gummed and dried, whereas, in adrier 35 to 50 feet long with the envelope flap lapped one inch, there are usually from 400 to 600 envelopes on the drier chain before the envelope can be folded. It often happens that the machine has to be stopped, and when this occurs on the old style machine over-drying immediately occurs, causing the sealing flaps to curl, and more often than not these envelopes with curled sealing flaps are baled as waste. Under this process if the machine is stopped, curling can occur only on the three or four envelopes actually in transit through the gumming device. This is a very important feature, because spoilage is considerable with the old systems. Under this process the adhesive drying speed is not substantially affected by weather conditions, such as high humidity, which is often a very serious obstacle in drying envelopes under the old schemes, because the ordinary machines with the conventional drier when operating on damp days frequently require slowing down of the feeding speed of the envelope by fifty per cent.

It will be understood that I do not wish to be entirely limited to the simultaneous use of all the devices shown, because in some cases a very good adhesive seal can be obtained, for example by dropping the powder directly on the brushes without the use of a squirrel cage" l2. This deposition of the powder can be accomplished by the worm screw I3 alone.

It will be further understood that under some conditions the rollers l6 and I I may be omitted, and it will be further understood that under some conditions good results may be obtained by substituting some other form of device for the belt I8.

It will further be understood that the squirrel cage l2 may be used without the brushes l4 and I5. -It is therefore intended herein to claim various combinations of the devices shown, particularly in view of the fact that I believe myself a pioneer in the art of quick drying at high speed, without the use of drying means other than the application of dry to wet adhesive.

I claim as my invention:

1. A device of the class described comprising, a conveyor for moving articles, means for applying water-soluble adhesive to a face of each article while moving, a pair of rotary members for applying dry powdered water-soluble adhesive to said wet adhesive of each article while it continues to move, means for feeding powdered adhesive to said rotary members, means acting to distribute the dry adhesive, and means including mohair material operating to remove surplus powdered material from each adhesively treated area.

2. A device of the class described comprising, a conveyor for moving articles, means for applying water-soluble adhesive to a face of each article while moving, a pair of rotary members for applying dry powdered water-soluble adhesive to said wet adhesive of each article while it continues to move, means for feeding powdered adhesive to said rotary members, means for pressing and wiping the mix to distribute the dry adhesive, and means moving in a direction transverse to the direction of motion of the article for wiping oil the surplus adhesive.

3. A device of the class described comprising, a conveyor for moving articles, means for applying water-soluble adhesive to a face of each article while moving, a pair of rotary members for applying dry powdered water-soluble adhesive to said wet adhesive of each article while it continues to move, means for feeding powdered adhesive to said rotary members, including a screen through which the material passes on the way to said members, means for pressing and wiping the mix to distribute the dry adhesive therein and operating in direction of feed and at greater speed than the feeding speed, and means moving in a direction transverse to the direction of motion of the article for wiping off the surplus adhesive.

4. A' machine for applying and drying adhesive, having means for feeding articles, means for applying wet adhesive to each article, a duster and wiping mechanism comprising a revolving drum having perforations for dusting powdered adhesive onto the wet adhesive of each article, means for feeding dry powdered adhesive'into the drum, and a pair of rollers adapted to work said dry adhesive into said wet adhesive.

5. A machine for applying and drying adhesive, having means for feeding articles, means for applying wet' adhesive to each article, a.

duster and wiping mechanism comprising a slowly revolving drum having perforations for dusting dry powdered adhesive onto the wet adpowdered adhesive into said drum, means contacting the dry adhesive for rolling the same into said wet adhesive and having a surface speed faster than that of the feeding speed of'the article, and means for removing the surplus dry adhesive from said wet adhesive.

6. A machine for applying and drying adhesive having means for feeding articles, means for applying wet adhesive to each article, a duster and wiping mechanism comprising a slowly revolving drum having perforations for dusting dry powdered adhesive onto the wet adhesive of each article, means for feeding dry powdered adhesive into said drum, means contacting the dry adhesive for rolling the same into' said wet adhesive and having a surface speed faster than that of the feeding speed of the article, means for removing the surplus dry adhesive from said wet adhesive, including a brushing belt moving at high speed and in a direction trans I verse to the direction of feed of the articles. v

7. A machine for applying and drying adhesive, having means for feeding articles, means for applying wet adhesive to each article, a duster and wiping mechanism comprising a slowly revolving drum having perforations for dusting dry powdered adhesive onto the wet adhesive of each article, means for feeding dry, powdered adhesive into said drum, a pair of rollers for rolling said dry adhesive into said wet adhesive, one of the rollers contacting the dry ad'- hesive and being adapted to operate at a faster surface speed than that of the feeding speed of the article, and means for removing the surplus dry adhesive from said wet adhesive, said means including a brushing belt moving'at high speed and in direction transverse to the direction of feed of the articles, said belt having a fine brushing surface of material such as mohair.

8. A device of the class described comprising, a conveyor for' continuously moving articles, means for applying water-soluble liquid adhesive to an article while moving, means for applying dry powdered water-soluble adhesive to said previously appliedwet adhesive, including a pair a of rotary brushes by which the dry adhesive is applied, and a, rotary screen through which the adhesive'is delivered to the brushes.

9. A device of the class described comprising, a conveyor for moving articles continuously, means for applying water-soluble liquid adhesive to a predetermined area of an article as it moves, means for thereafter applying dry powdered water-soluble adhesive to the previously applied wet adhesive, said means comprising a pair of rotary brushes by which the dry adhesive is applied, a drum screen arranged above the brushes, a screw conveyor for moving powdered adhesive into the screen, and a shaft 'for rotating the screen, said shaft being rotatable within said conveyor.

10. A device of the class described comprising,

a conveyor,- for' moving articles continuously,

means for applying water-soluble liquid adhesive to a predetermined area of an article as it moves, means for thereafter applying dry powdered Water-solubleadhesive to the previously applied plied; a screen arranged above the brushes and from which the dry adhesive is discharged upon hesive of each article, means for feeding dry the brushes, means for cleaning the outside of the screen, and means for cleaning the inside of the screen, both of said last mentioned means acting to keep the screen open for allowing the passage of dry material therethrough.

11. A machine for applying and drying adhesive, having means for continuously feeding articles, means for applying wet adhesive to an article, means for applying dry adhesive to the wet adhesive, means for pressing the dry adhesive into the wet adhesive, means for removing surplus adhesive, comprising a belt which moves across the adhesive surface in a direction transverse to the direction of travel .of the article, means acting on the belt to salvage the picked-up surplus adhesive and a receptacle into which said salvaged material is delivered as a result of the action of the last mentioned means.

12. A device of the class described comprising,

a conveyor for continuously moving articles, means for applying water-soluble liquid adhesive to an article while moving, means for applying dry powdered water-soluble adhesive to said previously applied wet adhesive, means acting on the adhesive mixture for. pressing said dry adhesive into the wet adhesive, and a belt of mohair material adapted to remove surplus dry adhesive and pressing against the same and moving in a direction transverse to the direction of motion of the article.

13; A device of the class described comprising, means for feeding articles, plural means for respectively consecutively applying to the same area of an article, first a water soluble liquid adhesive, then a dry powdered water-soluble liq-- uid adhesive, and means for removing surplus dry adhesive consisting of a belt having a facing of mohair acting on said adhesive, in a direction transverse to the direction of motion of the article, and at a speed considerably greater than the feeding speed of the article.

14. A device of the class described comprising, means for feeding a blank, means for applyin liquid adhesive to the blank, means for applying dry adhesive powder to the liquid adhesive to quickly dry and. increase the total amount of the adhesive, means for rolling the dry adhesive powder into the liquid adhesive to hasten and make more thorough the mixing action, and means for removing surplus dry powder, following said rolling action.

15. A device of the class described comprising, means for feeding a blank, means for applying liquid adhesive to the blank, means for applying dry adhesive powder to the liquid adhesive to quickly dry and increase the total amount of the adhesive, and means for rolling the dry adhesive powder into the liquid adhesive to hasten and make more thorough the mixing action, said rolling means traveling in the same direction as the blank.

16. A device of the class described comprising, means for feeding a blank, means for applying liquid adhesive to the blank, means for applying dry adhesive powder to the liquid adhesive to quickly dry and increase the total amount of the adhesive, means for rolling the dry adhesive powder into the liquid adhesive to hasten and make more thorough the mixing action, and means for removing surplus dry powder, following said rolling action, said surplus-removing means moving in a direction transverse to the direction of movement of the blank.

17. A device of the class described comprising, means for feeding a blank, means for applying liquid adhesive to'the blank, means for applying dry adhesive to the liquid adhesive to quickly dry and increase the total amount of adhesive, and means for pressing the dry adhesive powder into the liquid adhesive to hasten and make more thorough the mixing action.

18. A device of the class described comprising, means for feeding a blank, means for applying liquid adhesive to the blank, means for applying dry adhesive to the liquid adhesive to quickly dry and increase the total amount of adhesive, means for pressing the dry adhesive powder into the liquid adhesive to hasten and make more thorough the mixing action, and means for removing surplus dry powder.

EDWIN G. STAUDE.

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