US2233361A

US2233361A - Adhesive sheet dispenser

Info

Publication number: US2233361A
Application number: US373954A
Authority: US
Inventors: Arthur A Anderson; Ralph H Munson
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: 3M Co
Priority date: 1941-01-10
Filing date: 1941-01-10
Publication date: 1941-02-25
Anticipated expiration: 1958-02-25

Description

A. A. ANDERSON ETAL Feb. 25, 1941.

' ADHESIVE 51mm DISPENSER Filed Jan. 10, 1941 2 Sheets-Sheet 1 Even/Z07 5 A Zorney Feb. 25, 1941. A. A. ANDERSON EAL 2,233,361

ADHESIVE SHEET DISPENSER Filed Jan. 10, 1941 2 Sheets-Sheet 2 A rrbqg Patented Feb.25, 1941 J 2,233,361

; UNITED STATES PATENT OFF-ICE? ADHESIVE SHEET DISPENSER Arthur A'. Anderson, Rose Township, Ramsey County, and Ralph H. Munson, St. Paul, Minn assignors to Minnesota Mining & Manufacturing Company, St. Paul, Minn., a corporation of Delaware ApplicationJanuary 1o, 1"9i1,'saa1ao.373;95i

6Claims. (c1. lei-845i This invention relates to a dispenser for northe tape is, dispensed for use is to be called the mally tacky or pressure-sensitive adhesive sheetfront end. I ing in roll form, such adhesive tape having a 1 Figures 1 and 2 are side elevations of the right paper or cloth backing, or a backing of a celluand left sides respectively (as one faces the malosic film, coated on one side with a tacky-adchine at its front end). r

hesive which is adherent without the necessity Figure 3 is a front elevation.

, of activation by water, solvents or heat, and t Figure 4 is a vertical section of the draft wheel which can be unwound from rolls thereof-withand clutch mechanism taken on the line. 4-4 out transfer or offsetting of the adhesive, due in Figure 3.

to the highly cohesive nature of the adhesive. Fi res 5 and 6 are ver ical s ctions taken on 10 One problem in using sheets carrying such lines 5,--5 and 66, respectively, in Figure 3; tacky pressure-sensitive adhesive is the difiiculty and Figure 7 is a vertical section taken on the in removing them in desired lengths from supply line 'I'| in Figure l.

rolls. Figures 8 and 9 are side-and front elevation The present invention has among its'0bjecviewsof the stripper wheel. 15 tives the following: r To the base II is rigidly attached the upright To provide a simple device whereby a predeframe l2 which, in the present embodiment, is termined lengthof pressure-sensitive adhesive cast inone long relatively, thin'piece with varisheeting is accurately measured and thrust out ous projecting lugs at proper. points to which are in position ready for grasping and severance, attached the various parts of the machine, all with its adhesive portionfree from contact with of said parts being supported directly or indiany object except at its inner end; i rectly by the frame l2. Base H may be ofheavy To provide a dispenser which can be easily weight to prevent movement of the portable maadjusted as varythe predetermined unit length chine during use. v of tape within-a substantial range, and which The supp y rollRof pres u ess sit ve dhes can be operated to dispense tape accurately tape S s carried on e p 0 h d u measured in lengths which are multiples of the 25 towa ds the rear of the machine while the unit length, while permitting the dispensing of mechanism for withdrawing the tape from the desired fractional lengths when something less supply roll and dispe s g i in ngths ready f l than aunit lengthKor multiple thereof) is deuseis towardsthefront. 30 sired; Tape holder drum 2! may be of a size to re- To provide such a device wherein the cutting, ceive the standard commercial sizes of rolls of means will not become clogged with adhesive; pressure-sensitive adhesive tape such as that To provide such a device wherein the severed sold under the tralde-mark Scotch," for examedge of each length will be a .smooth, straight ple, but if desired, the machine may be provided 35 cut; I with several interchangeableudrums of-varying To provide such a device wherein the severing sizes. of eaich length may be by tearing" it off with The periphery of tape drum 25 is provided at one hand rather than by use of a mechanical intervals with ridges -25a extending parallel to 40 cutting means, but so arranged and equipped the drums axis so as to provide a tight fit be-' 40 that such ftearing may be done without distween the drum and the roll of tape notwith- .turbi-ng the alignment of the undispensed porstanding the slight variance in size of rolls that tion of the tape in the machine; and, are used from time to time. The ridges also help To provide such a device which may be entirely to prevent slipping. mainually operated but which requires the use of Tape drum [5 is journaled onto axle-bolt 28 only one hand at any time when dispensing. so as to turn freely thereon between the head The machine that is described and illustrated 26a and a flanged part so as to be stopped in the following description and drawings as againstlengthwise movement. Lug lZb is proillustrative of our invention is a portable manvided as a part of frame I! to provide adequate ually operated tape dispenser, particularly suited support for axle-bolt 26 which pierces the lug 50 for use on store counters to dispense pressureat right angles to the upright frame i2 and parsensitive adhesive tape used in sealing packallel to base II. The end of axle-bolt 26 is in ages. threaded engagement with lug I2b, said engage- In the accompanying drawings the end of the ment being sufficiently tight to make the pin 'machine at which it is operated and from which relatively rigid in the frame. Head 26a is 55 knurled to form a thumb-turn. The axle-bolt may be turned by the thumb-turn to permit ad- Justment the tape drum 25 laterally in respect to the machine as a whole so as to adjust roll R of tape S behind draft wheel 32 in proper alignment.

The tape S is withdrawn from thesupply roll R and'projected through the machine by reason of its temporary adherence to the periphery of the draft wheel 32 which is a part of the dispensing mechanism at the forward part of the machine.

Draft wheel 32 is mounted to rotate freely on shaft 21b. Just below draft wheel 32 the frame i2 is provided with lug 12f (Figure.3).' At the right of draft wheel 32 there is a circular side plate-21 which is provided at its lower edge with lug 21a. Lugs 12! and 21a register with each other so that they may be held together by screws 35 which are in threaded engagement with lug i2}; Shaft 21b is held rigidly in plate 21 so that it is rigid in relation to the upright 7 frame l2, perpendicular thereto and parallel with the axis of the tape holder drum 25.

The periphery of draft wheel 32 to which tape S temporarily adheres as it is being drawn through the machine, is straight knurled in lines 32, and deep enough so that stripper wheel 31 may be inserted in the groove to a depth of about half the diameter of stripper wheel 31.

- Stripper wheel'arm 36 is held in place by being V shaped at its lower end to register with lugs i2f and 21a (Figure 5) and pierced by holes b to admitscrews 35, holes 361) being sufficiently large to permit adjusting the position of arm 38 to bring stripper wheel 31 into proper position relative to the severing knife 33 and draft wheel 32, after which screws 35 are tightened so that arm 36 is held rigid by the pressure of lug 21a and of lug i2! on either side. At its upperend stripper wheel arm 36 is split to form two arms 380., having between them suflicient space to permit stripper wheel 31 to turn freely on the pin 3'") which is journaled in arms 38a (Figures 8 and 9). Stripper wheel 31 is preferably quite small in diameter, as compared with the draft wheel, and is shaped so that its periphery 31a is very narrow or knife-like. It is located a sub stantial distance forwardly of the point at which the tape first contacts'the draft wheel.

Arm I2d extends upwardly from the top of frame l2 and to it is removably attached (by screws 34) a fixed transverse shearing blade or knife 33, located tangentially and in close proximity to the periphery of draft wheel 32 and with its edge pointing toward, and inclose proximity to, stripper wheel 31, so that adhesive tape passes under the shearing edge and then over the stripper wheel during rotation of the draft wheel (see Figure 5). The advancing tape is projected outwardly by the stripper wheel, and can be severed by grasping the end of the tape and pulling thetape against the blade. The blade or knife has a straight edge, as distinguished from a sawtoothor serrated edge, permitting of a clean cut. The knife edge is preferably only sufficiently far from draft wheel 32 to permit free movement of the wheel when its periphery is carrying a thickness of tape, and sufliciently above stripper wheel 31 to permit tape to be bent by stripper wheel 31 outwardly away from draft wheel 32, and sufficiently close to stripper wheel 31 so that tape is stripped off directly after it passes the knife edge.

Pin 40 which is rigidly attached to frame I2 at a point below draft wheel 32 where the frame is reinforced bylugs l2e, carries idler pulley 33, around which the tape may be trained (see S in Figure 1), whenever a greater pull by draft wheel 32 is needed than is provided by running tape S direct from roll it to wheel 32.

Draft wheel 32 is driven by the power wheel 24a through the clutch cam 240 which is rigidly attached to the wheel 24a. The side of draft wheel 32 which is adjacent to power wheel 24a is cut away in the form of a deep and wide concentric groove designed to receive cam 0 so that draft wheel 32 may turn freely in close proximity to power wheel 24a without contacting cam 240. g 1

Similarly, there is rigidly attached to side pla e 21 the clutch cam 21c. Also the adjacent side of draft wheel 32 is cut away to receive the cam and to pemiit wheel. 32 to'turn freely in close proximity to plate 21 without contacting cam 21c.

Refening to Figure 6, the

spaces

28a, 29a and 30a between the cam 24c and the inside rim of draft wheel 32 are of a size to receive

rollers

23, 29 and 30. When any one of therollers is located in relation to its space as is roller 23 in Figure 6, such roller is free to turn. But the

spaces

28a, 29a and 30a taper so that when a roller is located as are

rollers

23 and 30 in Figure 6, it is wedged tight between cam 24cand wheel 32 and cannot turn.

Similarly, the space 3la (Figure 4) between cam 21c and rim of wheel 32 permits roller 3i to turn freely. But the space tapers so that when roller 3! is located in the particular position shown in Figure 4, the roller is wedged tight and cannot turn.

In actual practice the taper of the spaces is such that only a slight change of position of the roller will either wedge the roller or render it free to turn. A greater distance is shown in the drawings for sake of clarity.

Referring to Figure 6, when the mechanism is motionless, at least one of the three rollers will be held by gravity in a wedged position between cam 24c and wheel 32 (like roller 28) so that when power wheel 24a, and with it cam 24c, is turned clockwise, draft wheel 32 is moved in unison therewith. But when power wheel 23a, and with it cam 24c, is moved counter-clockwise, all

the rollers 23, 23- and 30 are rolled away from their wedged position to where they are free to turn so that no turning impulse is applied to draft wheel 32.

To insure against any slight turning of wheel 32 in a counter-clockwise direction, the clutch cam 21c and its roller 3i, as previously described, are provided.v If the working of the parts or snap of the tape or other cause tends in any wayto turn the draft wheel counter-clockwise (Figure 4), the roller 3|, being held by gravity in wedged position in its space, instantly brakes the draft wheel. But when draft wheel '32 is turned clockwise by force of power wheel 24a, the roller 3| is moved toward its'space 3ia where 'it is free to turn, and being free to turn, it

cannot brake the wheel 32. Y

If there were any backward rotation of draft wheel 32, accuracy of measurement of dispensed lengths would be lost; also it would cause spoilage of the tape due to overlapping of adhesive coated surfaces upon each other. I

Instantaneous braking of the draft wheel 32 against backward turning, as contrasted with the delayed braking action secured by other one-way driving mechanisms, such as a ratchet, provides positive prevention of even the slightest shortening of the length of tape that has been projected. Likewise, since at least one of the three

rollers

28, 29 or is always in wedged position, the draft wheel 32 turns instantly as soonas power wheel 24:: is turned, so that the length of tape projected will coincide precisely with the amount of turn of the power wheel 24a, the length of whose turn is measured and controlled accurately as hereinafter described.

Accuracy of-measurement is particularly desirable in the dispensing of label tape which is printed to form a series of labels, such as airmail stickers. The mechanism herein described is inherently of a kind that minimizes inaccuracies and the accumulation of inaccuracies and permits the reduction of backlash to a negligible amount.

Power wheel 24a which turns draft wheel 32 is actuated by sprocket wheel 24, the two wheels 24 and 240 being spaced apart and joined by a common journal 24b. The upright supporting frame I2 is provided, at its upper forward portion, with lug IIc which is pierced in a direction perpendicular to frame I2 and parallel with the axis of the tape holderdrum 25 to form a bearing which receives the Journal 24b.

Wheels

24 and 24a and their journal 24b are all rigid in relation to each other but free to turn in the bearing that pierces lug Ho.

The journal 24b is pierced to receive shaft 21b which is rigid in relation to lug I20 and frame I! but is adjusted so that journal 24b turns freely between I20 and 21b.

The sprocket wheel 24 is actuated by chain 23 which passes over it in operative engagement therewith, being attached at its forward end to pin I90. on the forward part of 'the operating lever l9; and being attached at its rear end to coil spring 22 which is loaded to draw the chain rearwardly. The rear end of spring 22 is anchored to arm I 2a which is an extension of frame l2. On the front end of the lever I9 is fixed a handle 20 of a size and shape to receive the operator's hand or finger when the lever is to be pressed downwardly.

The operating lever is is attached to the machine in such a manner that by a downward stroke it drawschain 23 downwardly and forwardly so as to turn sprocket wheel 24 clockwise (looking towards the left side of the machine).

At the point where arm l2a is Joined to the frame I2, the rear end of lever I9 is pivoted to theirarne by the pivot 2i. The pivot has adequate support in the frame because the thickness of the frame is supplemented at this point by the thickness of the arm I2a. One of the ends of pivot 2| is formed into a screw-head 2Ia to permit adjustment of the pivot. Pivot 2| is in threaded engagement with frame I2, said engagement being sufficiently tight to make the pivot relatively rigid in the frame. The part of the pivot which passes through lever I! is not threaded, and is :Iournaled into the lever.

To prevent its lateral movement, the lever II is flanked on either side by guide plates I3 and I4. Plate I4 is pivoted to the frame I2 bypivot 41. Plate I4 is made thicker at this point by lug I40 which is a part of plate I4, and lug l2h is likewise provided as a partof frame I2, so that pivot ll may have adequate bearing. Pivot 4| may be in threaded engagement with either the frame or plate and journaled into the other. Plate I4 is also removably attached to another part of frame I2 by lug Ila, which is a part of plate ll. At the point where lug a meets frame l2, lug Ila isreduced in size to form pin Mb which extends through slot I20 to the other side of frame I2. Pin Ilb is threaded at its outer end to receive thumb-screw I8. By loosening screw I8, plate I4, may swing about pivot ii to the extent allowed by slot I2g.

Plate I 3 is rigidly attached to plate I4 by screws I5 and IS. The plates are held apart enough to permit passage of lever I9 between them by collars around the screws and between the plates (like collar I1).

Collar I1 also limits the downward stroke of lever I9, and a similar collar around screw I6 limits the upward stroke so that by loosening screw I8 and raising the front ends of plates I3 and I4, the stroke is shortened. Thus, the unit length of tape that is automatically measured by the machine may be accurately varied by a simple resetting of the machine without substitution of new parts.

Mode of operation Supply roll R. of pressure-sensitive adhesive tape S is mounted on the drum 25,-and by turning thumb-turn 26a, the drum may be adjusted laterally to align it directly behind the draft wheel 32, so that when the tape is threaded through the machine it will contact the stripper wheel 31.

The tape S, being wound on the roll R with its adhesive side facing inwardly, is led from roll R over draft wheel 32, the adhesive side contacting the draft wheel's periphery, until the forward edge of the tape extends as far asthe cutting edge of knife 33.

The normal position of the lever I9 is at the uppermost limit of its stroke, as in Figures 1, 2 and 3. It is held there by tension of spring 22. The hand of the operator presses lever I9 downto the limit of its downward stroke, 1. e. until lever I9 is stopped by collar I! (Figure 3). Collar Il may be raised or lower to limit .the length of the stroke and thereby to limit the unit length of tape dispensed to any length within that dispensed by the levers longest stroke, by raising or lowering the lever guide plates I3 and I 4 and fixing them in the desired position by v tightening thumb-turn I8.

The downward stroke of .the lever I8 pulls chain 23 which turns sprocket wheel 24 clockwise (as one faces the left of the machine as in Figure 2), and since power wheel 24a and the sprocket wheel are rigidly fixed to acommon journal 24b, the wheel 24a and its clutch cam 24c move clockwise in unison with the sprocket wheel. The cam 240, through at leastone of the

rollers

28,29 and 30 (in a manner previously described), imparts this impulse without lag or loss ofmotion to the draft wheel 12 so that draft wheel 32 also turns clockwise in unison with the sprocket wheel. v

The adhesion of the'tape S to the draft wheels periphery either when the tape is threaded directly from roll R to wheel 32 or by way of idler pulley 39 (as S is'threaded in Figure 1) is sufficient to withdraw the tape from the roll 'Rand project it beyond the cutting edge of the knife 33. v

Normally, the tape would continue to adhere to the draft wheel asthe wheel turns, but just asthe tape moves beyond the knife edge, the

[128138 meets the stripper wheel 31 and is forced tion:of tape projects clear of the machine and in position to be readily grasped. I

Straight knurling crosswise of the draft wheel 32, among other functions, provides the wheel with greater traction upon the tape being removed from the roll R, since thepull is in a direction tangential to the draft wheel 32. It also causes the wheel to exert less resistance to stripping off of the tape due to the limited contact area.

with-it wheel 24a and-cam 24c.

vAt the end of the down stroke of lever IS, the I lever is released and is returned to its normal position by spring 22 In so doing, it causes sprocket wheel 24 tov turn counter-clockwise and But as previously described, by reason of the rollers 28-, 29 and 30, no motion is conveyed to draft wheel 32 when wheel 24a moves counter-clockwise. Also, as previously described, draft wheel 32 is locked against any counter-clockwise or backward movement by clutch cam 210 on side plate 21 and by roller 3 I'.

Therefore, when the lever I9 is released by the operator all the mechanism is automatically returned to its original position in readiness for dispensing the next length, but during such return the draft wheel 32 remains stationary so that the projected length of tape S is still held out away from the machine ready to be cut on by pulling it diagonally up and across the knife edge. To do this, the operator may use the same hand that he used to press the lever. hand is free at all times to hold the article to which the tape is to be applied. If longer strips are desired, they may be'secured by repeated depressions of the lever before the length is cut oil".

During cutting, the slightly sidewardpull on the tape does not disturb the alignment of the unprojected portion partly because of the adhesive engagement of the tape with the draft wheel and the close set of the knife to the draft wheel. This permits the use of a straight knife edge in place of the old sawtooth type of cutter to which bits of adhesive will stick and which leaves a ragged edge.

A further insurance against the knife becoming gummed with adhesive is that the machine is designed to apply the cutting force to the non- I advance the next length.

The illustrated embodiment may be entirely encased, with operating'lever I9 and handle 20 extending through an opening therein and with at His other small opening at the front through which the tape is thrust by the machine, such opening shaped to expose enough of the knife 33 to permit severing the projecting tape as describedabove. In such an arrangement the thumb-turn 18 may project through an are shaped slot in the casing, calibrations being marked on the casing adjacent the slot to show what length of tape will be dispensedwhen the thumb-turn I8 is set at a given point. H

If atmospheric'conditions curl the tape so as to make it desirableto augment the outward guidance of projected tape, an extra guide wheel A or .roller of small diameter, similar to stripper wheel 31,-may be rotatably held by an arm forwardly of the stripper wheel 31 and in line therewith to guide the projected tape voutwardlystill farther away from contact with the. machine or casing.

The illustrated embodiment 'is suited to handling tape, but the invention may take form in machines where draft wheel 32 is of great width andv where there are aplurality of stripper wheels 31 to handle sheets of, material wider than the sheets commonly called tape. The sprocket wheel 24 may bepower driven, or lever l9 may be operated by a foot treadle.

We claim:

1. In a pressure-sensitive adhesive sheet dispenser, a holder for a supply roll of the adhesive sheeting, draft wheel means for withdrawing the adhesive sheeting from the roll by adhesive contact therewith, having a grooved periphery to limit the trans-verse extent of contact, one-way driving means for rotating the draft wheel in a direction to withdraw adhesive sheeting from its roll and means for preventing backward rotation of the draft wheel, a small rotatable stripping element. extending'intothe grooved portion of the draft wheel and located a substantial distance forwardly of the point at which the adhesive sheeting first contacts the draft wheel, adapted to separate the adhesive sheeting from the draft wheel and direct it outwardly as the latter rotates, a substantially fixed transverse shearing blade located in. close proximity to the periphery of the draft wheeland with its edge pointing toward, and in proximity to, said stripping element, so that adhesive sheeting passes under the shearing edge and then over the stripping element during rotation of the draft wheel and the adhesive sheeting can be severed by grasping the projecting part and pulling the nonadhesive backing against the shearing edge without substantial removal of the rearward portion of the adhesive sheeting from the draft 'wheel and without drawing it out of alignment.

2. The device of claim 1 in which the means for rotating the draft wheel includes a lever and means for controlling the stroke of the lever so as to vary the unit length of adhesive sheeting dispensed with each stroke of the lever.

3. The device of claim 1 in which the stripper element is arotatable wheel of an extremely small diameter as compared to the draft wheel's diameter and having an edge-like periphery.

4. The device of claim 1 in which the draft wheel's peripheral surface is knurled.

5. The device of claim 1 in which the knife blade has a straight edge located close to the draft wheel with a clearance not substantially more than sufiicient to permit passage of the adhesive sheeting between the knife and the draft wheel, and in which the stripping element is a wheel of very small diameter compared with the diameter of the draft wheel and with an edgelike periphery located so close to the knife edge as to strip the adhesive sheeting from the rotating draft wheel directly after the adhesive sheeting has passed beyond the knife edge.

6. In a portable dispenser for pressure-sensitive adhesive tape, adapted for counter use in stores, means for supporting a supply roll of tape. a draft wheel having its peripheral surface straight knurled in lines parallel to the wheel's axis for withdrawing the tape from said roll and having a grooved periphery to limit the transverse extent of contact, one-way driving means for rotating said draft wheel in a direction to withdraw tape from the roll, said means being adapted to impart its impulse to the draft wheel without loss of motion, and means for preventing backward rotation of the draft wheel, an operating lever for actuating said driving means and means for adjusting the stroke of the lever. a stripper wheel having an edge-like periphery and held in the grooved portion of the draft wheel and extending into said grooved portion a sufficient distance so that tape adhering to the draft wheel's periphery will be lifted off said periphery by said stripper wheel as the tape is advanced against the stripper wheel, said stripper wheel having an extremely small diameter as compared to the draft wheel's diameter, a fixed transverse shearing blade having its shearing edge in close proximity to the draft wheel at a point in relation to the stripper wheel such that tape will pass the shearing edge directly before it meets the stripper wheel, so that tape can be severed by grasping the projecting part and pulling the non-adhesive backing against the shearing edge without substantial removal of the rearward portion of the adhesive sheeting from the draft wheel, without drawing it out of alignment and without contacting the blade with the adhesive.

. ARTHUR A. ANDERSON.

RALPH H. MUNSON.