GB2081221A - Tab inserters - Google Patents

Abstract

A tab inserter is extended outwards beyond the knife (5) and is provided, at the outer end of the extension, with an anvil (27) and a device (9) which cooperates with the anvil to grip the outer end of a strip of tab material before a tab is severed and swing the subsequently severed tab about the gripped end to positively insert its other end into a stack or apply it at a pinch point to a moving web being formed into a roll, said device (9) comprising a roller (23) mounted on the upper end of a vertical shaft (17) which is movable longitudinally of and rotatable about its axis to move said roller toward and swing it relatively to the anvil. <IMAGE>

Description

SPECIFICATION Tab inserters This invention relates to devices, hereinafter referred to as tab inserters, for cutting tabs from a continuous strip of tabbing material and inserting them at predetermined intervals between the sheets or turns of a stack or roll of paper or other material during the course of its formation.

When employing tab inserters with web-fed winding machines it is usual either to insert the tabs at the take-up point of the winding reel or to stick adhesive tabs to the web at a pinch point remote from the reel. When tabs are to be inserted at a pinch point either in the path of the web or at the intake of the reel, care must be exercised in positioning the head of the inserter, since if the head is too close to the pinch area a tab could be sucked into the pinch point before being severed from the strip, with the consequent danger of the material being torn and the machine jammed.

Conversely, if the inserter head is positioned too far away from the pinch area it is necessary to drop the tab into position with the risk of it being displaced by air turbulance at the pinch point.

It is therefore, the principal object of the present invention to achieve positive insertion of tabs while maintaining the inserter head at a suitable distance from the point of insertion and to this end, according to the invention, the inserter is extended outwardly beyond the knife and the outer end of the extension is provided with an insertion device having a pivotally mounted insertion member which is automatically operable to frictionally engage the tabbing strip at or near its outer end, prior to severing a tab therefrom, to press the strip against the surface of an anvil or the like also positioned at the outer end of said extension, and, after severing a tab therefrom, to swing the severed tab, about that part thereof in contact with said surface, to move the end just severed towards a suitable point of insertion or application before moving away from said surface and returning to its initial position.

Said insertion member may be moved in a substantially vertical plane, towards and away from said surface, by a first solenoid and about a substantially vertical axis in contact with said surface, by a second solenoid, actuation of which is coordinated with that of the first solenoid and the knife-operating mechanism to achieve the required sequence of operations.

When employing solenoids it is preferable to mount them at a point remote from the insertion device and transmit their movement to the insertion device through small-diameter connecting rods.

For use with non-adhesive tabs the insertion device is required to insert each tab directly into the pinch point between a web and the reel on which it is being wound before releasing the tab and swinging back but for use with adhesive tabs it is sufficient to apply each tab to a web at a pinch point in advance of the reel, since as soon as an adhesive tab is applied under pressure to a web it will adhere to and pass along with the web to the reel even though it has been applied to the web some yards from the reel.For use with adhesive tabs, the insertion device is preferably coated with P.T.F.E. or other material affording minimal adhesion to the tabs and the extension is preferably provided with a ramp, also coated with P.T.F.E. or other material affording minimal adhesion to the tabs, up which the outer end of a tab can pass to the insertion device without the rest of the tab coming into contact with the extension.

The invention will be described, by way of example, with reference to the accompanying drawings in which: Fig. 1 is a side elevation of the outer end of a tab inserter extended and provided with an insertion device in accordance with the invention; and Fig. 2 is a perspective view of the outer end of a tab inserter having a modified form of extension for the insertion device.

In common with conventional tab inserters, the one shown in the drawings has a motor-driven feed device (not shown) for advancing a strip 3 along a guideway 4 to a rotary knife 5 which cooperates with a die 6 to sever tabs of the required length from the end af the strip.

The strip 3 may be plain or coated with an adhesive material and in the latter case, it is expedient to protect the adhesive-coated side of the strip by means of a further strip (not shown) of siliconised paper which is removed prior to reaching the knife 5 and returned to a rewind reel or waste receptacle.

In conventional machines it is necessary for the free end of the strip to enter a stack of sheets to be tabbed or be applied at a pinch point to a moving web immediately prior to a tab being severed therefrom and this requirement involves the difficulties already referred to.

In order to overcome these difficulties and achieve accurate placement of tabs, the inserter is extended outwards by means of an outrigger comprising upper and lower members 1, 2 slidably or otherwise adjustably mounted on the guideway 4 to vary the length of tabs dispensed.

An insertion device shown generally at 9 is mounted on the outrigger member 2 and an anvil 27 is mounted on the outrigger member 1 and may be made rotatable about a vertical axis relative thereto through the interposition of a thrust race (not shown). A ramp 28 and a deflector 14 are mounted on the outrigger members 2 and 1 respectively for guiding the outer end of the strip 3 issuing from the guideway 4, between the device 9 and the anvil 27.

The device 9 includes a bell-crank lever 10 pivotally mounted at 11 for movement about a substantially horizontal axis in a bracket 7 on the outrigger member 2 and having one end secured at 12 to a rod 13 connecting it to a first solenoid (not shown) mounted beneath the guideway 4.

The other end of the lever 10 engages one end of a substantially vertical shaft 1 7 which is slidable in and rotatable with a pinion 1 8 meshing with a substantially horizontal rack 1 9 secured to the forward end of a rod 20 connecting the rack to a second solenoid (not shown) also mounted beneath the guideway 4. The shaft 1 7 carries, at its upper end, a bracket 22 in which a roller 23 is rotatably mounted and the pinion 1 8 is prevented from rising out of engagement with the rack 1 9 by a trap 8 which is mounted on the outrigger member 2 and also serves as a guide for the rack.

When the feed device is operated to advance the strip 3, the device 9 is positioned with the roller 23 immediately under the anvil 27, but separated therefrom to allow the end of the strip to pass from the ramp without hindrance beneath the anvil.

At the end of the feed step, the first solenoid is operated to move the lever 10 in an anti clockwise direction, as viewed in the drawing, to move the shaft 1 7 and roller 23 upward relative to the pinion 19 and thus press the strip 3 against the underside of the anvil 27. The knife 5 is then operated to sever the projecting end of the strip 3 to form a tab, after which the second solenoid is operated to move the rack 19 forward or backward.This movement of the rack 1 9 is instrumental in rotating the pinion 1 8 which is operative through the shaft 17 and bracket 22 to swing the roller 23 about a vertical axis and the friction between the roller and the tab is sufficient for the tab to rotate in contact with the under surface of the anvil until its recentiy severed end is positioned to be inserted in a stack of sheets being formed, stuck at a pinch point to a moving web being wound into a roll, or inserted in the pinch point between the web and the roll.In the case of a stack, the tab is released immediately upon insertion by deenergising the first solenoid, whereupon the lever 10 is movable in a clockwise direction about its pivot 11 to permit the shaft 1 7 and roller 23 to move downward relative to the pinion 1 8 but in the case of a web, the pinch effect exerted on the tab at its point of application to the web is sufficient to drag the inner end of the tab from between the roller 23 and the anvil 27 and the roller can be moved into its released position after the tab has gone. With adhesive tabs, these will adhere to the roller 23 which can be swung through a large angle before applying the tab to a moving web.If, then, the roller 23 and the ramp 28 are coated with P.T.F.E. or other material affording minimal adhesion, resistance to movement of the strip 3 along the outrigger is minimised and the adhesion of a tab to the web at the pinch point will be that much greater than its adhesion to the roller, so that removal of the tab from the roller will be accomplished without difficulty.

In contrast with the usual procedure, in which each tab is severed at the point of insertion, the present invention enables the tabs to be severed from the strip before being moved to the point of insertion. The inserter head carrying the knife can, therefore, be positioned at a point farther away from the point of application of the tabs than is possible without provision of the outrigger and insertion device.

In the arrangement shown in Fig. 1, in which the insertion device is mounted for pivotal movement through 360 , variation of the length of the tabs to be dispensed requires adjustment of both the upper and lower members 1, 2 of the outrigger.

In the modification shown in Fig. 2, in which like parts are indicated by the same reference numerals as in Fig. 1, the adjustable upper member 1 of the outrigger also supports the insertion device 9 through the medium of an angle bracket 14 secured at 15 to the member 1 and comprising an upright member supporting the ramp 28 and the pivot for the lever 10 and a transverse member which is apertured for the passage of the shaft 1 7 and forms a mounting for the trap 8.

This arrangement requires adjustment only of the member 1 to alter the length of the tabs to be dispensed. It is no longer possible, however, to rotate the roller 23 through 3600, but it is still possible to rotate it through more than 1 800 and to employ a right-handed or left-handed bracket dependent upon the direction in which the tabs are to be rotated.

Furthermore, in order to avoid having to adjust the length of the connecting rods to correspond with the adjustment of the outrigger, it is possible to mount the solenoids or other devices for operating the lever 10 and rack 19, on the outrigger instead of the main body of the inserter.

Claims (12)

1. A tab inserter of the kind in which a continuous strip of material advanced by a feed device along a guideway is automatically cut into tabs of the required length by a knife at or near the end of the guideway, characterised in that the guideway is extended outward and the outer end of the extension is provided with an insertion device having a pivotally mounted insertion member which is automatically operable to frictionally engage said strip at or near its outer end prior to severing a tab therefrom, to press the strip against the surface of an anvil mounted on the outer end of said extension, and, after severing a tab therefrom, to swing the severed tab about the part thereof in contact with said surface, to move the end just severed towards a suitable point of insertion or application before moving away from said surface and retuming to its initial position.

2. A tab inserter according to Claim 1, wherein said insertion member is a roller, rotatable about' an axis parallel with the surface of said anvil, for .

engaging and moving said tabs, said roller being carried by a first pivotal member rotatable about an axis at right angles to the axis of rotation of said roller and movable longitudinally of its axis of rotation by a second pivotal member mounted on said extension for rotation about an axis at right angles to the axis of rotation of said first pivotal member.

3. A tab inserter according to Claim 2, wherein said first pivotal member is a substantially vertical shaft rotatable about its axis by a first operating device, said shaft being positioned below said anvil and provided at its upper end with a mounting for said rotatable roller.

4. A tab inserter according to Claim 3, wherein said second pivotal member is a two-armed lever, one arm of which is connected to a second operating device and the other arm of which engages the lower end of said first pivotal member.

5. A tab inserter according to Claim 4, wherein said first and second operating devices are solenoids located remote from said insertion device and connected to said pivotal members by rods extending longitudinally of said extension.

6. A tab inserter according to Claim 5, wherein said first pivotal member carries a pinion which is rotatable by a rack connected to one of said solenoids by one of said rods.

7. A tab inserter according to Claim 6, wherein one arm of said second pivotal member is connected directly to the other of said solenoids by the other of said rods.

8. A tab inserter according to any preceding claim, wherein said insertion member is pivotable through 3600 in a substantially horizontal plane.

9. A tab inserter according to any preceding claim, wherein said extension is in the form of an outrigger adjustably mounted on said guideway to permit variation in the length of tabs dispensed.

1 0. A tab inserter according to any preceding claim, wherein said extension includes a ramp positioned in the path of a strip of tab material issuing from said guideway, and extending upwardly to said insertion device.

11. A tab inserter according to Claim 10, wherein said roller and said ramp are coated with a material affording minimal adhesion to the tabs.

12. A tab inserter according to Claim 11, wherein said material is P.T.F.E.

1 3. A tab inserter substantially as hereinbefore described with reference to or as shown in the accompanying drawings.