US3259323A - Adhesive-applying apparatus - Google Patents

Description

July 5, 1966 c. J. SANDERS 3,259,323

ADHESIVE-APPLYING APPARATUS Filed March 23, 1964 2 Sheets-Sheet l July 5, 1966 c, J, SANDERS 3,259,323

ADHESIVE-APPLYING APPARATUS Filed March 23, 1964 2 Sheets-Sheet 2 [.2 61 4' 5? %&

V I 7 0, jzz/e/ziar 43 42 C/larwfcfialzda/ts 4Z7 4 9 gflgawU QTEQAJZZZILJ United States Patent 3,259,323 ADHESIVE-APPLYIN G APPARATUS Charles J. Sanders, De Pere, Wis., assignor to Paper Converting Machine Co. Inc., Green Bay, Wis, a corporation of Wisconsin Filed Mar. 23, 1964, Ser. No. 353,745 1 Claim. (Cl. 239-585) This invention relates to adhesive-applying apparatus, and, more particularly, to apparatus for delivering adhesive onto a rapidly traveling web while the same is in the process of being rolled on itself about tubular cores.

The invention finds utility in the operation of rewinding toweling and tissue-exemplified in the manufacture of toilet tissue, where the tail of a web is secured to the main body of the wound roll.

The instant invention constitutes an improvement on my prior Patent No. 3,064,862. Reference may be had to the earlier patent for details of the environmental construction which may be omitted here for the sake of brevity.

The principal requirements of an adhesive-applying system of the character with which the instant invention is concerned include fast and reliable action. Winders currently operate in the range of 1500-1750 feet per minute, and are run continuously. Presently, there are no devices available for applying adhesive in the manner of the instant invention. The need for adhesive is primarily a quality" and a sheet count problem. The inventive device does several things to finished product quality:

(1) Sheet counts are exact from rewinder to consumer because glue keeps the end of the web secured to the roll from rewinder to wrapper;

(2) Tails are not mangled or loosened in handling from the rewinder to the wrapperthereby resulting in improved product appearance;

(3) Operating labor now employed to take care of loose tail problems is eliminated; and

(4) Rewrap of packages where the tail protrudes from the package or interferes with proper scaling is eliminated.

It is, therefore, a general object of this invention to provide an adhesive-applying system, particularly useful in connection with winders (alternatively termed rewinders) which meets the requirements of high speed and commercially reliable operation.

Another object of the invention is to provide an electromechanical system for controlling the application of adhesive to a fast-traveling web wherein the parts coact in a novel fashion to achieve high speed, reliable operation.

Still another object of the invention is to provide a unique valving arrangement useful in applying adhesive to a fast-traveling web, while a concomitant objective is to provide a unique electrical system for operating solenoid-equipped valves.

Other objects and advantages of the invention may be seen in the details of construction and operation set down in this specification.

The invention is described in conjunction with an illustrative embodiment in the accompanying drawing, in which:

FIG. 1 is a schematic representation of winder apparatus to which this invention has application;

FIG. 2 is a fragmentary elevational view of the adhesive-applying apparatus of FIG. 1;

FIG. 3 is a schematic representation of a wiring diagram of the electrical system associated with the adhesiveregulating valves of FIG. 2;

FIG. 4 is an enlarged sectional view of one of the valve devices seen in FIG. 2;

FIG. 5 is a perspective view, partially broken away, of the resilient valve element seen at the extreme lower Patented July 5, 11966 "ice pogtion of FIG. 4, but on enlarged scale relative thereto; an

. FIG. 6 is a bottom view of the element of FIG. 5.

Referring now to FIG. 1 of the drawing, the numeral 20 designates a fast-traveling web which is being unwound from a jumbo parent roll (not shown) and which passes over idler roll 21 associated with the machine frame (not shown). The general rewinder can-be seen in the US. Patent of Kwitek and Nystrand No. 2,769,600. The web 20 is partially wrapped around a perforating roll 22 associated with a perforating head 23, details of which can be seen in Kwitek Patent No, 2,870,840. Thereafter, the transversely perforated web is partially wrapped about a slitting bedroll 25 which coacts with a slitter roll 24-. In some instances, the slitter rolls may be eliminated and the rewound log transversely severed by means of a log saw such as that illustrated in the application of John J. Renard, Serial No, 247,433, filed November 28, 1962, now abandoned.

The web 20 is then partially wrapped around a cut-off bedroll 26 and then wound upon a mandrel 27, suitably equipped with a paperboard core as at 270. A substantially completely wound roll is seen in the lower portion of FIG. 1 on the mandrel 27b. Cut off of the web is achieved by a cut-off mechanism schematically shown in FIG. 1 and designated 28 as part of the bedroll 26. Timing for the cut-off is achieved through the mechanism 29, and after cut-01f is achieved, the inventive adhesive-applying system generally designated 30 functions to apply spots of adhesive transversely across the width of the web 20.

The adhesive-applying system can be seen in FIG. 2, which is a side elevational view of the apparatus designated 30 in FIG. 1, wherein the apparatus includes a frame extending across the width of the rewinder.

Referring now to FIGS. 2 and 4, the numeral 31 designates a casing in which liquid adhesive A is supported for subsequent discharge against the web 20. The casing 20 is equipped with the cover 32 which also provides a support for a solenoid frame 33 (see particularly FIG. 4). The numeral 34 designates a dashed line construction in FIG. 4 representing the solenoid coil which is disposed about the solenoid armature 35. Extending downward from the solenoid armature 35 and connected thereto is a plunger 36 serving to expel the liquid adhesive against the Web 20.

The numeral 37 (still referring to FIG. 4) designates a clamping element serving to secure, by means of bolts 38, the solenoid frame to the cover 32. The numeral 39 designates generally a retracting mechanism for the solenoid armature 35 and the associated plunger 36.

The apparatus functions to expel liquid adhesive whenever the solenoid coil 35 is energized, whereupon the armature 35 is drawn smartly downwardly and moving the plunger 36 therewith. To prevent shock to the mechanism, a urethane shock absorbing pad 34a is provided in the solenoid against which the armature may bottom. Through the provision of the pad 34a and the clearance bore 33a, the illustrated assembly has been operated 500,000 cycles without any parts failure. The system is operative to place a spot of tail seal adhesive within A3 of a target point on the surface of a roll which was moving at 1500 feet per minute. Coincidentally, the retraction or spring return mechanism 39 is extended, so that when current flow to the solenoid coil 34 is interrupted, the spring return mechanism 39 takes over and retracts the armature 35 to the position illustrated in FIG. 4.

The plunger 36 extends into the casing 31 and protecting the bottom portion of the solenoid against splashing and other penetration by the liquid adhesive A is a splash boot 40. Still referring to FIG. 4, it is seen that the splash boot 40 is constructed of rubber and has a recessed portion 40a in the central bottom of the cup-shaped structure. The recessed portion follows the plunger 36 during movements of the latter under the influence of the solenoid coil 34 and the spring return mechanism 39.

The numeral 41 designates generally the nozzle structure through which adhesive is pumped under the action of the plunger 36, the nozzle 41 including a nozzle body 42 which is threaded as at 42a for the receipt of a locking nut 43. The body 42 extends through an aperture 44 in the bottom of the casing 31 and the locking nut 43 is drawn up tight against the bottom of the casing 31 so as to clamp the same against the shoulder 42b of the nozzle body 42. Extending upwardly from the nozzle body 42 is a guide tube 45 to facilitate rapid assembly after cleaning and which surrounds the plunger 36. Just below the inlet tube 45, the valve body 42 is apertured as at 46 to provide inlet openings for the liquid adhesive A to enter the nozzle bore 47.

Provided at the bottom of the nozzle body 42 is a slit valve 48 (see also FIG. which is secured to the valve body by means of a supporting ring 49 engaged with the nozzle body 42 by means of detents 49a. The nozzle is equipped with a detent-type locking ring for rapid removal of the tip and also to overcome the problem of a threaded type tip gradually backing off because of vibration in the machine.

In operation, the downward movement of the plunger 36 expels liquid adhesive from the bore 47 through the resilient valve 48 which is equipped with a slit as at 48a (see FIG. 5). For the purpose of insuring this pistonlike action, the plunger 36 is equipped with a barrelshaped or spheroidal segment 50 at its lower end which effects a seal with the inner walls of the bore 47 irrespective of misalignment of the plunger 36. In like fashion, the upper end of the plunger 36 is also equipped with a spheroidal segment as at 51 which is positioned within a bore 52 provided within the armature 35. The bore 52 is closed by an annular plug 53 in which the lower end 54 of the retraction connection 55 is threadedly received. Separating the spheroidal segment 51 from the plug 53 is a urethane pad 56 and a urethane ring 57 is installed between the end wall 35a of the armature 35 and the lower portion of the spherical segment 51. Thus, slight movement of the plunger 36 within its armature connection is tolerable without hammering tending to distort or rupture the armature 35. At its upper end, the armature 35 bears against a leather packing 58 which is disposed about the connection member 55 and confined within a casing 59 provided atop the solenoid coil 34 and serving to protect the armature 35.

Proceeding upwardly in FIG. 4, it is seen that the connection member 55 is pivotally coupled to a U-shaped element 60 which serves as an upper limit or stop for the coil spring 61. The lower limit for the coil spring 61 is provided by an arm of a second U-shaped member 62, the U-shaped member 62 benig secured to the rigid portion of the apparatus 30 as at 63.

In operation, the downward movement of the armature 35 is accompanied by a downward movement of the U-shaped member 60, tending to compress the spring 61. When the electrical current to the armature coil 34 is interrupted, the spring 61 takes over and returns the apparatus to the condition seen in FIG. 4.

As soon as pressure is relieved on the slit valve element 48, the slit 48a is closed and no liquid adhesive A is permitted to flow out of the dome-shaped slit valve element 48. However, when the plunger 36 is depressed, the lower spheroidal segment 50 serves as a piston (in combination with the bore 47) to force a discrete amount of liquid adhesive into the slit valve element 48 and thereafter out of the slit 48a into impinging engagement with the moving web.

The electrical system will now be described and in conjunction with FIG. 3. First, it should be appreciated that quick and precise actuation of the solenoid armature 35 is required. In the winding of toilet tissue consisting of 4 /2" squares at a rate of about 1750 feet per minute, the apparatus 30 must be fully operated within about of a second so as to place the dime-sized spot of adhesive properly on the traveling web. For this purpose, I employ a silicon-controlled rectifier, type 2N1916, and which is designated 64 in FIG. 3, to control the various solenoid coils 34. A source of alternating current as at 65 is provided which is coupled to a transformer 66 and a full wave rectifier 67. The essentially direct current ouput from the rectifier 67 passes through a limiting resistor 68 and charges a condenser 69. Thus, upon the triggering of the rectifier 64 which serves as a gate, the condenser 69 discharges rapidly through the solenoid coils 34 to bring about the smart movement of the associated plungers 36.

The gating of the rectifier 64 is provided by an elec trical signal coming through the line 70 which is governed by a fiipflop circuit 71 and a limit switch 72. The limit switch 72 is operatively associated with the timing mechanism 29 and determines which revolution of a given winding cycle is the one in which the adhesive application occurs. This is determined by the rotation of the bedroll 36 which operates at a constant velocity. The flipflop circuit 71 is responsive to a second switch within the timing mechanism 29 for the purpose of delivering the electrical signal along the line 70 at just the precise time within a given revolution of the winding cycle. Simultaneously with the delivering of the electrical signal along the line 70, a signal is delivered along the line 73 to an RC time delay circuit 74. The output of the time delay circuit 74 is coupled to another rectifier 75 and serves to gate the same, which action shuts off the current in rectifier 64 and determines how much current drains from the condenser 69.

In the operation of the device, the liquid adhesive initially enters the chamber 48b provided by the slit valve element 48 and additional pressure developed by the plunger 36 causes the liquid adhesive to flow out of the slit 48a (see FIG. 5). After discharge, the plunger 36 rises, creating a partial vacuum in chamber 48b and bore 47. This follows from the fact that slit 48a acts as a check valve, sealing off entry of air intochamber 4811. When the plunger 36 is fully retracted, the adhesive enters the evacuated chamber 48]) through the passages 46. The arcuate nature of the generally spheroidal segment 50 in effect develops a line-type seal with the wall of the bore 47 to insure that adequate pressure is developed within the chamber 48b and loss of fluid laterally is avoided through the provision of the annular upstanding rib 480 provided as part of the cup-shaped valve element 48.

In the operation of the device, accuracy of adhesive spot placement is achieved, along with reliability of longtime performance. This is important with web travel of the speeds indicated, i.e., upwards of 1600 feet per minute. In such an installation, timing is ordinarily set for a given speed, but it is possible to equip the system with a governor-controlled timing switch as at 30a in FIG. 1 to correct for timing errors if they occur. Most rewinders are operated at a constant speed so as to eliminate the need for such a timing switch.

While in the foregoing specification a detailed description of an embodiment of the invention has been set down for the purpose of explanation thereof, many variations in the details herein given may be made by those skilled in the art without departing from the spirit and scope of the invention.

I claim:

A mechanism for applying adhesive to a moving web, comprising a frame equipped with an adhesive flow passage, conduit means for delivering fluid adhesive thereto, a plunger reciprocably mounted in said passage for ejecting adhesive from one end of said passage, said plunger being equipped with radially enlarged ends, the plunger enlarged end adjacent the passage one end being axially arcuate to develop a line-type seal with the wall of said passage, solenoid coil and armature means operatively coupled to said frame and the other end of said plunger for moving said plunger toward said passage one end, the plunger other enlarged end being rockably mounted in said armature whereby the axis of said shaft is displaceable from the axis of said passage without affecting the said line-type seal, a resilient element interposed between said plunger and said frame for returning the plunger to retracted position away from said passage one end, shock pad means on said frame for cushioning the impact of said plunger with said frame following retraction thereof by said resilient element, and a resilient cup-shaped closure member closing said passage one end, said closure having a cut extending therethrough normally effecting a seal for said passage, but under the pressure developed by said plunger opening to permit ejection of said adhesive, said closure being equipped 20 with an annular upstanding rib adjacent the open top necessarily developed by the cup-shape, said rib cooperating with said frame to develop a seal against lateral flow of adhesive.

References Cited by the Examiner UNITED STATES PATENTS M. HENSON WOOD, 111., Primary Examiner.

R. S. STROBEL, Assistant Examiner.

Images