US3640245A

US3640245A - Circulating device

Info

Publication number: US3640245A
Application number: US1797A
Authority: US
Inventors: Charles F Schaefer
Original assignee: Individual
Current assignee: SCHAEFER MACHINE COMPANY Inc PO BOX 512 BOSTON POST ROAD CLINTON CT 06413 A CORP OF CT
Priority date: 1970-01-09
Filing date: 1970-01-09
Publication date: 1972-02-08
Anticipated expiration: 1989-02-08

Abstract

This disclosure relates to a device for preventing adhesive in an adhesive coating mechanism from thickening and decreases the problem of air drying of such adhesive. A mechanism is provided to constantly recirculate liquid adhesive which is deposited between a pair of cooperating rolls so that excess liquid is removed from between the rolls and air drying thereof is substantially decreased.

Description

United States Patent Schaeier 51 Feb. 8, 1972 [54] CIRCULATING DEVICE [72] Inventor: Charles F. Schaefer, captaints Drive film's Point, brook, Conn. 06498 221 Filed: Jan. 9, 1970 21 Appl.No.: 1,797

[52] US. Cl. ..ll8/259- [51] Int. Cl. B05c 1/08 [58]- FieldofSearch ..1 18/203, 227, 259, 261;

117/ l l l [56] References Cited UNITED STATES PATENTS 2,953,476 9/1960 Armstrong .Q ..u7/111 2,981,226 Murray ..1 18/227 3,094,924 6/ 1963 Stark .118/259 X 3,097,968 7/1963 Schaefer ..1 18/259 3,162,545 12/1964 Dearsley ..1 18/203 Primary Examiner-Louis K. Rimrodt Attomey-Delio and Montgomery [57] ABSTRACT This disclosure relates to a device for preventing adhesive in an adhesive coating mechanism from thickening and decreases the problem of air drying of such adhesive. A mechanism is provided to constantly recirculate liquid adhesive which is deposited between a pair of cooperating rolls so that excess liquid is removed from between the rolls and air drying thereof is substantially decreased.

10 Claims, 6 Drawing Figures BY Dee/ GJWQ W I32 Chades F. SchaeFer ATTORNEYS HEU FEB 8 I972 sum 3 BF 2 INVENTOR CIRCULATING DEVICE This invention relates to machines for applying liquid coatings such as adhesives to sheet material, and more particularly relates to such machines wherein the liquid is deposited between two cooperating rolls which define a liquid reservoir therebetween.

A device of the type to which the present invention is applicable is generally shown in US. Pat. No. 3,097,968. In such a coating applying apparatus there is provided a pair of cooperating rolls wherein one roll is utilized to place an adhesive coating or layer on strip material passing thereby. The second roll which is generally of smaller diameter is in rolling contact with the coating roll and maybe termed a coating control roll. The two rolls define a reservoir or cavity therebetween which, together with suitable damming means placed at each end, retains a liquid adhesive in the reservoir.

In operation, liquid adhesive is deposited in the reservoir through a conduit and as the two rolls rotate the coating control roll causes a thin coating of the liquid adhesive to be spread evenly along the coating roll which then contacts the sheet material passing thereby.

Where the adhesive is of the solvent-containing cement type a problem is presented due to air drying of adhesive on the rollers, and the agitation in the adhesive produced by the rotation of the rollers hastens evaporation of the solvent.

Thus, the adhesive will quickly thicken beyond the point of practical use. Dependent upon the type of adhesive, this thickening may take place in as little as minutes. Where the adhesive is thin with a high percentage of solvent, the adhesive will flow to the sides of the rolls and then down to a catch tank at a substantially controlled rate. However, the solvent type adhesives generally must be used in a mixture with a high percentage of solids and a low percentage of solvents, and the adhesives will not flow freely towards the end of the rolls or pass through a drain hole at a practical rate. The wider the sheet material to be processed the greater the problem. For example, the roll lengths may vary from l5 up to 42 inches or greater.

The present invention is designed to overcome the problems presented by the use of viscous liquids.

Accordingly, an object of this invention is to provide a new and improved machine for applying a liquid coating to sheet or strip material.

Another object of this invention is to provide a new and improved adhesive applying machine. including apparatus for recirculating the adhesive to prevent rapid air drying thereof.

A further object of this invention is to provide a new and improved device to be used in combination with a pair of rolls defining a liquid reservoir which includes a liquid moving means which moves along the length of the reservoir to remove excess liquid therefrom and decrease the amount of adhesive exposed to the air.

Briefly stated, the invention in one form thereof comprises an adhesive coating roll and a coating control roll disposed in rotating contacting relation and defining a reservoir which holds the adhesive to be coated. The apparatus further comprises an adhesive tank together with a lead-in conduit and also a return conduit to the tank. A paddlelike member is provided which will sweep down the length of the roll defined reservoir to remove excess liquid therefrom and propel it into the return conduit. On the return path,mechanism is provided for rotating the paddle 90 so that it will not produce flow of the liquid in the opposite direction.

The features of the invention which are believed to be novel are particularly set forth and distinctly claimed in the concluding' portion of the specification. The invention, however, both as to its organization and operation, together with further objects and advantages thereof, may best be appreciated by reference to the following detailed description taken in conjunction with the drawings, wherein:

FIG. 1 is a top plan view of the preferred embodiment of the invention, as combined with a plurality of rollers for applying glue;

FIG. 2-is a front elevational view of the preferred embodiment of the invention shown in FIG. 1;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a sectional view taken along line 44 of FIG. 3, showing the toggle lever means in a locked position;

FIG. 5 is a view similar to FIG. 4, showing the toggle lever means ina released position about to be engaged by an abutment member; and

FIG. 6is a view taken along line 66 of FIG. 3.

As will be described in detail hereinafter, a liquid reservoir is definedbetween a coating roll 14 and a coating control roll 16 together with

damming plates

60 and 64 at the ends of the roll. Liqiiid is supplied to the reservoir through a conduit 149 from a tank 80, and a return to the tank from an overflow conduit 78 leading from plate 60. To move excess liquid to the overflow conduit, a support or carrier member 84 carries a paddlelike member 138 along the length of the reservoir in a liquid sweeping position toward the overflow conduit. On the return path the paddlelike member is rotated 90. When the paddlelike member returns to its starting point it is rotated back to itls' sweeping position and the cycle is then repeated.

With reference to FIGS. l-3, the apparatus comprises a frame lfl' having spaced apart upright side frame members 12 and l3. A coating roll 14 and a coating control roll 16 are rotatably mounted between

side frames

12 and 13 on

shafts

18 and 20, Irespectively. A drive means (not shown) drives a sprocket chain 22 received on a sprocket wheel 24 on a shaft 26 rotatably carried by side frame 13. Shaft 26 has a gear 28 thereon in driving relation with a gear 30 on the shaft of a roll 32. A roll'34 is driven by similar means (not shown).

Rolls

32 and 34 cooperate with coating roll 14 to apply a liquid coating to strip material passing therebetween.

Shaft 26 carries a second sprocket member 38 which is connected to a sprocket member 40 by means of a sprocket chain 42. Sprocket 40 is on the shaft 18 of coating roll 14.

Also carried on shaft 18 is a pulley 44 which drives a belt 46 about apulley 48 mounted on a rod 50 which is rotatably carried by

side frames

12 and 13. Rod 50 is threaded and serves asa lead"v screw, as will hereinafter be explained. Gear 52 is mounted on shaft 18 so as to engage and drive a gear 54 on shaft 20 of roll 16. As sprocket chain 22 is driven it drives shaft 26 and, in turn, roll 14. Roll 16 in contact with roll 14 is driven thereby and acts to control the layer of adhesive that passes between the nip of the rolls. Sheet material 56 to be coated passes beneath roll 14 and over

rolls

32 and 34. In this manner, the liquid deposited in the reservoir between

rolls

14 and 16 is carried down to the upper surface of material 56 and evenly applied thereto by roll 14.

Rolls

14 and 16 define a liquid cavity or reservoir 58 therebetween which receives the coating liquid. The liquid in cavity 58 is maintained therein by a plate 60 having thereon a wear layer 62 of hard fibrous material, and a plate 64 also having thereon a wear layer of hard fibrous material.

Layers

62 and 66 contact the ends of

rolls

14 and 16.

Plate 64 is resiliently mounted on bolts 68 carrying springs 70 to insure a tight seal between the rolls and damming plates. A spring :72 is located on a guide 74 to maintain layer 66 in contact with the ends of rolls l4 and 16. The pressure of the damming; means provided by

plates

60 and 64 is not sufficient to hinderrotation of the rolls I4 and 16. Plate 60 and layer 62 thereon define an aperture 75 therethrough which lead to a conduit 78. Conduit 78 leads to a liquid tank or reservoir 80. This permits excess liquid in cavity 58 to pass into conduit 78 and return by gravity to tank or reservoir 80.

Carried between side frames 12 and 13 are a pair of rods 82 which slidably carry a support or carrier member 84. A member 86 is pivotally mounted to support member 84 as more clearly shown in FIG. 3. Member 86 carries a cantilever spring member 88 which is attached to a threaded shoe 90 which rides on shaft 50 as more clearly seen in FIGS. 4 and 5. When shoe 90 is in engagement with shaft 50, rotation of shaft 50 will produce motion of carrier member 84 from side frame 12 towards side frame 13. Cantilever spring 88 is biased upwardly by means of a spring 92 connected to member 84. A toggle linkage 94 acts to either lock shoe 90 on shaft 50 or upon release of the toggle permits spring 92 to lift spring 88 and shoe 90 therewith out of engagement with shaft 50. Toggle 94 includes a lower lever 96 pivotally mounted to member 86 by means of a pin 98. Lever 96 is pivotally connected at its upper end to a lever 100 by means of a pin 102 and lever 100, in turn, is pivotally mounted to a block 104 carried on member 84 as by means of bolts 108 and studs 110. Stud 110 is also adjustable to limit the pivotal movement of lever 100.

A lever 114 is pivotally mounted to an overhanging support member 112 carried on member 84. Lever 114 is adapted to reset or relock toggle 94, as will be hereinafter described.

A boltlike securing member 116 is located on arm member 84 and extending therefrom is a spring strip 118 which winds about a spool 120 carried on the left upright 12, FIG. 1. Toggle 94 as shown in FIG. 4 is adapted to be broken by an abutment member 122 carried on the right upright 12, FIGS. 1 and 2, when arm member 84 travels to the extreme right position shown in dotted line in FIGS. 1 and 2.

When am 84 travels to the extreme-left position shown in FIGS. 1 and 2, lever 114 carried on extension 112, engages an abutment in the form of a bolt 124 which is resiliently mounted to a supporting member in the form of another bolt 126 by means of a spring 128. This will again lock the toggle 94. When toggle 94 is an unlocked or raised position, as shown in FIG. 5, nut 90 is out of engagement with shaft 50. Conversely, when toggle 94 is in a locked position, as shown in FIG. 4, nut 90 is held in threadable engagement with shaft 50.

When nut 90 is out of engagement with shaft 50, the tension in spring strip 118 will return carrier member 84 on slides 82 from the right-hand position to the left-hand position as shown in FIGS. I and 2.

With the mechanism thus described, it will be seen that carrier member 84 initially travels from left to right, as viewed in FIG. 1, until abutment member 122 breaks the lock of toggle 94. Then spring 118 returns support arm 84 along rod 82 to the left-hand position, as shown in FIG. 1, while nut 90 is withdrawn from engagement with shaft 50.

As will now be described, the support arm carries a paddlelike member which acts to return excess liquid back through conduit 78 through reservoir 80, and is then rotated 90 as it returns through the roll cavity or reservoir to its initial position to commence another cycle of operation.

A shaft 132 is rotatably mounted in arm member 84 and supported therein as by means of a washer 134. A member 136 is carried on shaft 132 which is adapted to produce rotation thereof as hereinafter described. At the bottom of shaft 132 is a paddle member 138.

As more clearly shown in FIG. 6, shaft 132 has a portion 140 of generally rectangular cross section but with two concave portions essentially 90 apart which are adapted to be engaged by a roller 144 carried on a lever 142. Lever 142 is pivotally mounted to arm member 84 on the lower surface thereof.

Lever 142 is biased towards arm member 84 by means of spring 145. Shaft 132 is adapted to be in either of one of two positions which are 90 apart and the arrangement of lever 142, roller 144 and spring 145 in conjunction with the con- I cavities 140 acts as a detent to releasably lock shaft 132 in either one of these two positions.

When arm member 84 moves to the right as viewed in FIGS. 1 and 2, such that member 136 is struck by abutment 146, shaft 132 will be rotated by the torque exerted thereon to member 136. This force will be sufficient to cause portion 140 to turn against the bias of spring 145, FIG. 6, and then roller 144 will fall into the other concavity in portion 140. When the support arm travels sufficiently to the left in the opposite direction, arm 136 which will be 90 disposed from the position shown in FIG. 1, will hit an abutment member 148 which will then rotate

shaft

132, 90 in the opposite direction.

In operation, pump 152 will force the glue or other viscous liquid through a conduit 149 to the cavity or reservoir defined by

rolls

14 and 16 and

dams

60 and 64. As the machine is operated, shaft 50 is driven through belt 46 with nut in contact therewith. Accordingly, carrier member 84 will travel from the left to the right as viewed in FIGS. 1 and 2 with paddlelike member 138 moving broadside to the glue in the reservoir. As paddlelike member 138 moves along the reservoir it will push the liquid therein into conduit 78 and, hence. return it to tank 80. When arm 74 has reached the right extremity of travel, member 122 breaks toggle 94 and shoe 90 is raised. At the same time, shaft 132 is rotated 90 by abutment 146 acting on member 136. Carrier member 84 is now returned to the left under the pull of spring strip 118. At this time, the thin edge of paddlelike member 138 travels through the liquid and thus does not move or paddle the liquid in the wrong direction. When carrier member 84 has traveled to the left most extremity, toggle 94 will be again locked by engagement of abutment bolt 124 on lever 114 and nut 90 will be forced down into engagement on shaft 50. The described cycle of operation will then be repeated.

A further benefit from this arrangement is the substantial elimination of the normal rotary motion of the adhesive in the reservoir due to rotation of the roll. This rotary motion agitates the liquid therein and will unduly hasten solvent evaporation and thickening of the cement.

It may thus be seen that the objects of the invention set forth as well as those made apparent from the preceding description are efficiently attained. Inasmuch as other embodiments of the invention may occur to others skilled in the art, the appended claims are intended to cover all modifications of the disclosed embodiments of the invention as well as other embodiments thereof.

What is claimed is:

1. A device for use in combination with an apparatus for applying a viscous liquid through a narrow elongated orifice and having an elongated reservoir defined above said orifice, a liquid tank, a conduit leading from said tank to the reservoir, an overflow opening at one end of said reservoir defining means, a second conduit providing communication between the overflow opening and the tank together with means for moving liquid from the tank to the reservoir, comprising a carrier member, means movably mounting said carrier member above said reservoir, a generally flat surfaced paddlelike member carried by said carrier member extending into the reservoir, means for moving said carrier member on said mounting means toward the overflow aperture so that said paddlelike member forces liquid in the reservoir toward the overflow aperture, means for rotating said paddlelike member as it nears said overflow aperture and returning said paddlelike member toward the other end of the reservoir whereby a minimum surface area of said paddlelike member is presented to the liquid upon the return travel.

2. The device of claim 1 further including spaced apart frame means and support means comprising rods upon which said carrier member is slidable carried between said frame means.

3. The device of claim 2 wherein said drive means includes a threaded shaft rotatably mounted between said frame means, and a threaded member on said carrier adapted to be engaged on said shaft.

4. The device of claim 3 further including a locking mechanism for holding said shoe on said shaft, means for unlocking said locking mechanism and lifting said shoe when said paddlelike member approaches said overflow aperture.

5. The device of claim 4 wherein said locking mechanism is a two-link toggle and said means for unlocking is an abutment member which is struck by said toggle linkage as the paddlelike member approaches the overflow aperture end of the reservoir.

6. The device of claim 4 further including means disposed at the nonoverflow aperture end of the reservoir for relocking tions essentially 90 apart, means mounted to both of said frame means for rotating said paddlelike member between said two positions.

8. The device of claim 4 wherein said locking means is a two-link toggle, one end of one toggle link being pivotally mounted to said carrier member, one end of said other toggle link being pivotally mounted to said shoe, the other ends of said links being pivotally mounted to each other.

9. The device of claim 4 further including spring means for returning said carrier member toward the other end of said reservoir.

10. Apparatus for applying liquid adhesive or the like to sheet or slab material, spaced apart support means, a coating roll and coating control roll rotatably supported between said support means in rolling contact and defining a reservoir therebetween, end plates at the opposite end of the rolls extending above the line of rolling contact of the rolls and arranged to define the reservoir with the rolls, one of the end plates having an overflow opening therein, a tank, a conduit extending from the overflow opening to the tank, a pump and conduit for delivering liquid from the tank to the reservoir; a member movable back and forth over said reservoir and a generally flat surfaced paddlelike member connected to said member movable so that said paddlelike member forces liquid in the reservoir toward the overflow opening and means for rotating said paddlelike member as it nears said overflow opening and returning said paddlelike member toward the other end of the reservoir whereby a minimum surface area of said paddlelike member is presented to the liquid upon the return travel.

Claims

6. The device of claim 4 further including means disposed at the nonoverflow aperture end of the reservoir for relocking said locking mechanism.

7. The device of claim 2 wherein said paddlelike member is mounted to said carrier member for rotation between positions essentially 90* apart, means mounted to both of said frame means for rotating said paddlelike member between said two positions.