US2542804A - Apparatus for applying adhesive to a mass of wood chips - Google Patents

Description

4 0 l a 2 m M. w J .g I Fr 7 W m j R H A F F APPARATUS FOR APPLYING ADHESIVE TO A MASS OF WOOD CHIPS Feb. 20, 1951 Filed Jan 9, 1948 Feb. 20, 1951 F. FAHRNI 2,542,804

APPARATUS FOR APPLYING ADHESIVE TO A MASS 0F WOOD CHIPS Filed Jan.- 9, 1948 5 Sheets-Sheet 2 Feb. 20, 1951 F. FAHRNI 2,542,804

APPARATUS FOR APPLYING ADHESIVE TO A MASS OF WOOD CHIPS I Filed Jan. 9, 1948 3 Sheets-Sheet 3 Patented Feb. 20, 1951 APPARATUS FOR APPLYING ADHESIVE TO A MASS OF WOOD CHIPS Fred Fahrni, Zurich, Switzerland Application January 9, 1948, Serial No. 1,361 In Great Britain September 4, 1945 Section 1, Public Law 690, August 8, 1946 Patent expires September 4, 1965 9 Claims.

The present invention relates to an apparatus for applying adhesive to a mass of chips, which may include shavings and other discrete particles of wood or other similar material, for the manufacture of pressed articles.

In the manufacture of artificial boards or other shaped articles made of wood particles of miscellaneous shapes bonded together, the uniform mixture of the adhesive with the wood particles improves the quality of the product. When using a liquid adhesive many difficulties interfere with obtaining a uniform distribution of the adhesive on the wood particles forming the mass which is to be bonded and tend to cause production of a lumpy, uneven mass.

The present invention has for an object to provide an improved apparatus for applying adhesive evenly distributed throughout the mass of chips or the like which are to be bound together to form a finished product.

Another object is to so distribute the adhesive in the mass of particles and to so apply it to the discrete particles of wood or other material that maximum efflciency of the quantity of adhesive used will be obtained.

Another object is to provide an efficient apparatus whereby a mass of material may be alternately tumbled and put in contact with the adhesive the more advantageously to provide a thorough distribution of the adhesive throughout the material.

The invention provides in its preferred embodiment a hopper and an adhesive-applying roll or drum or, better, a plurality of such drums, to which adhesive is applied in a thin film and from which it is taken up by the chips or other similar material which i alternately tumbled in the hopper and pressed into firm contact with the adhesive. For the purpose of tumbling and mixing the material as well as pressing it into contact with the adhesive-applying drum a plurality of machine embodying the invention illustrating the location and operation of the diiferent cylinders or rolls.

fluted rolls are arranged in the hopper and means Fig. 2 shows the adjustable measuring means for the glue transfer roll operating in the glue trough.

Fig. 3 shows the scraper co-operating with one of the glue-applying rolls as associated with a baffle plate for mixing and overflow adjustment.

Fig. 4 is a perspective view of the arrangement of Fig. 1 as seen in the direction of arrow Z, Fig. 1, including the driving means for the corrugated rolls lying above the gluingrolls, all baflles and the glue transfer rolls lying underneath same and their driving means being left out for the sake of the clarity of the drawing.

Fig. 5 shows the arrangement and drive of the glue transfer rolls.

Figs. 6 and 7 illustrate a movable bearing for the corrugated rolls, Fig. 6 being a sectional elevational view and Fig. 7 a horizontal sectional view.

Figs. 8 and 9 are cross-sectional views, respectively elevational and horizontal, of an adjustable yieldable carriage-bearing system for a glue transfer roll.

In the illustrative apparatus adhesive i applied in a thin film to a plurality of similar rolls or drums. A hopper is arranged over the adhesiveapplying drums and fits over the drums in a manner to contain a considerable mass of chips which may be shavings and discrete particle of miscellaneous sizes and shapes but all of relatively small size for convenient handling in the machine. The term "chips is used in its broad sense to define a variety of material and not in a restrictive sense.

By maintaining a thin film of liquid adhesive on the two drums and by agitating the mass of material and bringing various portions thereof repeatedly into contact with the drums the adhesive is well distributed throughout the mass.

A supply of liquid glue or other adhesive is maintained in a tank I in which roll 2 is partly immersed and rotate in the direction of the arrow. A scraper 3 (Fig. 2) that may be adiusted through a threaded control without any clearance serves for measuring the amount of glue required for the feeding of the following series of glue transfer rolls.

The transfer of the glue over the rolls: 5, 6, I on one hand and 5', 6', and l on the other serves to apply a thin film of glue to the two large gluing rolls 8 and 8'. It should be remarked that the intermediary transfer rolls 5, 8, and I and 8'. 8', and I are separated from one another by gaps that become narrower in the mentioned order of succession of the rolls in each series while the peripheral speed of said rolls increases in accordance with the same order of succession.

A closed container 8 allows the continuous introduction of wood particles from above in the direction of the arrow Y so as to drop on to the rotary gluing roll 8. Above each of said gluing rolls 8 and 8 and relatively close thereto are provided three corrugated cylinders lying one behind another, said corrugated rolls or cylinders shown, respectively, at l8, Ii, and I2 and at l8, II, and I2, providing for the continuous tumbling of the wood chips and intimate contacting thereof with the gluing rolls. The first corrugated roll or cylinder l8 takes hold of the wood particles with a greater peripheral speed than that of the roll 8 and carries said particles along in the same direction of rotation through 8. The second corrugated roll or cylinder ll assuming an opposite direction of rotation and lying also at a suitable distance from the roll 8 shows a higher peripheral speed than the first corrugated roll or cylinder l8. Said roll rotating in the opposite direction takes hold of the particles fed by the first corrugated roll and provides for their tumbling and stirring with one another while furthermore the particles that have already received a glue coating rub against those that are not yet entirely coated so as to provide all the particles with a uniform coat of glue through the mutual action of the rolls and particles. The corrugated roll II also engages masses of chips and carries them in the direction of its rotation between itself and the smoother glue-applying roll 8. The chips by this action are moved along in a direction opposite to the direction of peripheral movement of the glue-applying roll, wiping against the roll to pick up glue. The third corrugated roll l2 rotates again to move its periphery in the same direction as that of the gluing roll 8 and lies also at an adjusted distance from the latter and rotates at a still greater peripheral speed than the corrugated roll ll; said roll I! engages the particles again and urges them in a direction such that they move away from the following particles over the ballle plate l8 of metal sheet and fall on to the second gluing roll 8' with reference to which the whole operation begins over.

In order that the gluing rolls 8, 8 may retain a clean peripheral surface beyond the baflle plates l8, l8 there is associated with each bailie a scraper l4, l4 (Fig. 3) that serves for removing any particles and glue residuum that may possibly adhere thereto. Such residual glue is continuously removed by the wood particles wiping over the scrapers under the action of the last corrugated roll l2.

As the gluing is entirely provided over the two rolls 8 and 8' and this leads to a thorough coating of the particles with glue'the machine described may be termed a twin machine.

After the particles have left the machine, having passed over the second baflle plate l8 of metal sheet, they drop on to a belt conveyor lying underneath same and are fed by this to the means used for further operation, that is for moulding and compression.

The mechanical part of the machine will now be described in further detail:

Fig. 4 shows the main control system of the machine that is actuated by a motor driving the smallbelt pulley i8 controlling thelarge belt pulley I 8 through the fiat belt I1.

The pinion 28 carried by the main drive shaft l8 drives the two large gears 22 and 228 through the intermediate gear wheel 2|, and these large gear wheels are carried by the same shaft as the corresponding gluing rolls 8 and 8' that are thus driven.

The pinions 28 and 28' that are in mesh with the gear wheels 22 and 22', respectively, drive in their turn the sprocket wheels Y28 and 24' that are rigid with the shafts carrying the said pinions 28 and 23' respectively. Said sprocket wheels drive through the chains 25 and 25' the cooperating sprocket wheels 26 and 26 that are rigidly secured to the shafts of the corrugated rolls l8 and I2 for the sprocket wheels 26 and I8 and I2 for the sprocket wheels 28'. i

The corrugated rolls II and II that rotate in reverse directions are driven through the large gear 21 rigid with the-shaft of the gluing roll 8; said large gear 21 engages an intermediary pinion 28 that in its turn engages the pinion 28 to the shaft of which are rigidly secured sprocket wheels 88 controlling respectively the shafts of the corrugated rolls II and II through the chains 8| and 81 and the sprocket wheels 82--82' rigid with said shafts. 1

The corrugated rolls l0; Ii; 12 and III; II and II are movably carried (Figs. 2, 6, and 7) in a manner such that in the case of any irregular feeding of wood particles said rolls may adjust themselves automatically to the thickness of the layer of particles passing in the gap between the corrugated roll and the gluing rolls. In order to prevent a crushing of the wood particles, especially when the mass consists mainly of wood shavings, by the heavy corrugated rolls the latter are carried by means of adjustable springs so as to nullify the effects of gravity. In order to check, however, an unlimited rising movement of the corrugated rolls their free shifting upward is restricted by means of an adjustable opposing spring 84. The bearlugs 88 of the corrugated rolls slide in a guiding groove 88. There is provided, as a packing between the corrugated rolls and the .wall of the closed container Qfor the mass of wood shavings or particles, a sheet of metal 81 that may slide inside a guiding groove and that rests on a ball bearing 88 surrounding the shaft of the corrugated roll considered. The metal sheet forming a packing is thus carried along in both directions by the upwardand downward-moving shaft of the corrugated roll.

In order to prevent, in case of any failure in the feeding of shavings or other particles,

any contact between the corrugated rolls and the gluing cylinders 8 or 8, the bearing for a corrugated roll is protected at its lower end by means of an abutment 89 forming simultaneously a securing bolt for the spring 88, whereby there always remains some clearance between the corrugated rolls and the gluing rolls or cylinders. I

Fig. 5 shows the driving means for the glue transfer rolls 5, 8, I and 5', 6, I',as provided again through the main control shaft is carrying the belt controlled pulley H. To the other end of the shaft I8 is keyed a pinion 40 controlling through an intermediary pinion H the auaaoc gear wheel 42 carried bythe shaft of the immersed roll I for controlling same. Said shaft of the immersed roll 2 carries at its opposite end a pinion 43 that is keyed thereto and that controls the two adjacent glue transfer rolls 5 and I through the corresponding gear wheels 44 and 44', rigid therewith. The gear system thus described provides a higher peripheral speed for the glue transfer rolls 5 and 5' than for the roll 2. This difference in peripheral speed results in furthering the spreading and drawing of the glue film.

The glue transfer rolls 5 and 5 carry each a further gear wheel 45 and 45 respectively, engaging the corresponding gear wheels 46 and 46' whereby they provide for the drive of the adjacent glue transfer rolls 8 and 6' also at a higher peripheral speed than the rolls 5 and 5.

The gear wheels 41 and 41 rigid with the opposite ends of the shafts of the glue transfer rolls 6 and 6 control through the gear wheels 48 or 48' the glue transfer rolls l--l" that are again caused to rotate at a higher peripheral speed than the rolls 6 and 6. Thus the peripheral speed increases continuously from one roll to the next in the order of rolls 2, 5, 6, I and 8 or 2, 5', S, l and 8'.

Figs. 8 and 9 show a movable bearing system for the glue transfer rolls, that is for the rolls 5-l, 5'l'. Between two glue transfer rolls that have stationary bearings, say between the rolls 2 and B (Fig, 1), there lies in fact a movable roll the possibility of moving of which is indicated by the straight arrows.

The possibility of shifting the bearings of such a roll has for its object to answer two purposes simultaneously: in the first place, it is possible thereby to provide a more accurate adjustment of the desired thickness of the glue film through a stop 54 that is adjustable through the operation of the threaded screw 53; this arrangement allows in fact an adjustment of the distance with reference to the two adjacent rolls lying in stationary bearings. A further threaded screw 50 provides an adjustment, corresponding to the tenacity of the glue, of the elastic pressure of the spring 49 acting on the bearing 5| of the roll shaft. On the other hand, the ad- -justrnent of the bearing considered allows in co-operation with the opposing spring 49 a shifting of the roll carried in its movable bearing in the direction of the arrow referred to, shown in Fig. 1. in case of the passage between the rolls considered of any shavings or other particles that are thicker than the gap provided therefor through a suitable adjustment. The spring 49 inthe case illustrated urges the roll bearing 5| that is guided in the groove 52 against the above-mentioned adjustable abutment 54.

The apparatus described herein embodies certain features of the apparatus described in applicant's prior application Ser. No. 617.881, filed September 21, 1945, now abandoned, and of which this application is a continuation-inpart.

The foregoing description of a particular apparatus is illustrative merely and is not intended as defining the limits of applicant's invention.

Iclaim:

1. In a machine for applying adhesive to chips or the like, in combination, an adhesiveapplying drum, means for applying adhesive to the surface thereof, a hopper positioned adjacent to the drum to contain a quantity of chips for engagement with the drum, means arranged within said hopper for agitating the chips in the hopper and pressing them against the drum comprising rotating rolls fluted to engage and push the chips forward in the direction of rotation of such rolls, said rolls being spaced from the adhesive-applying drum to permit the chips to be passed between the adhesive-applying drum and each fluted roll in the direction of rotation of the fluted roll; and means for rotating said fluted rolls at a greater surface speed than the surface speed of said adhesive applying drum. 2. In a machine for applying adhesive to chips or the like, in combination, an adhesive-applying drum, means for applying adhesive to the surface thereof, a hopper positioned over the drum to hold a mass of chips onand above the drum, a series of fluted rolls within the hopper parallel to and somewhat spaced from the adhesiveapplying drum and from each other to provide space for the passage of chips as the fluted rolls rotate within the mass of chips in the hopper, and means to drive the adhesive-applying drum in one direction and the fluted rolls in different directions to cause the chips to be wiped against the adhesive-applying drum both while being moved in the same direction as the surface of the adhesive-applying drum and while being moved in the opposite direction.

3. In a machine for applying adhesive to chips or the like, in combination, an adhesive-applying drum, means for applying adhesive to the surface thereof, a hopper positioned over the drurn to hold a mass of chips on and above the drum, means to press the chips against the adhesiveapplying drum comprising a series of fluted rolls within the hopper parallel to' and somewhat spaced from the adhesive-applying drum and from each other to provide space for the passage of chips as the fluted rolls rotate within the mass of chips in the hopper, means to drive the adhesive-applying drum at a predetermined surface speed, and means to drive at least two of the fluted rolls at a higher surface speed adjacent to the adhesive-applying drum and in the same direction and to drive a fluted. roll between said two fluted rolls in the opposite direcion 4. In a machine for applying adhesive to chips or the like, in combination, an adhesive-applying drum, means for applying adhesive to the surface thereof, a hopper positioned over the drum to hold a mass of chips on and above the drum, means to press the chips against the adhesiveapplying drum comprising a series of fluted rolls within the hopper parallel to and somewhat spaced from the adhesive-applying drum and from each other to provide space for the passage of chips as the fluted rolls rotate within. the mass of chips in the hopper, and means to drive alternate fluted rolls in opposite directions, respectively, and to drive the adhesive-applying drum.

5. A machine for applying adhesive to chips as defined in claim 4 wherein the successive rolls of i the series of fluted rolls are driven at successively higher surface speeds, substantially as described.

6. A machine for applying adhesive to chips comprising a plurality of relatively large adhesive-applying drums, means for supplying adhesive to the surfaces thereof, a hopper over said drums to hold a mass of chips engaging the drums, a series of fluted rolls arranged within said hopper and coacting with each adhesiveapplying drum to agitate the chips within the hopper and to cause the chips to rub against the adhesive-applying drums, means for driving the several rolls in directions to rub the chips against each adhesive-applying drum in opposite directions and to tumble and mix the chips, and a stripper blade engaging each adhesive-applying drum for separating the chips therefrom.

7. In a machine for applying adhesive to chips or the like, in combination, an adhesive-applying drum, means for applying adhesive to the surface thereof, a hopper positioned adjacent to the drum to contain a quantity of chips for engagement with the drum, and means arranged within said hopper for agitating the chips and pressing them against the drum to receive adhesive.

8. In a machine for applying adhesive to chips or the like, in combination, an adhesive-applying drum, means for supplying adhesive to the surface thereof, a hopper positioned adjacent to the drum to contain a quantity of chips for engagement with the drum, means arranged within said hopper for agitating the chips and pressing them against the drum to receive adhesive, said means comprising at least one roll arranged within said hopper parallel to and adjacent to the drum and means for driving said drum and 25 said roll with their adjacent sides moving in opposite directions.

9. In a machine for applying adhesive to chips or the like, in combination, an adhesive-applying drum, means for applying adhesive to the surface thereof, a hopper positioned above the drum to hold a mass 01' chips on and above the drum, means to press the chips against the drum comprising two fluted rolls within the hopper parallel to and somewhat spaced from the drum and from each other to provide space for the passage of chips as the fluted rolls rotate within the mass of chips in the hopper and means to rotate the drum and to rotate the two fluted rolls in opposite directions to force two streams of chips against the drum and between the drum and the respective rolls and toward each other and to tumble the meeting chips in the hopper. FRED FAHRNI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 686,930- Heard et al Nov. 19, 1901 1,931,570 Brown et a1 Oct. 24, 1933 2,177,093 Burke Oct. 24, 1939 2,302,526 Card Nov. 17, 1942 2,313,082 MacDonald Mar. 9, 1943

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