GB2055346A - Tab inserters - Google Patents

Abstract

A tab inserter severs a tab from a strip 3 advanced along a guideway 4 before moving the tab to a position for insertion into a stack of sheets or onto a moving web. The inserter carries a pivotally mounted device 9 which is automatically pivoted by means of solenoid 15 firstly about a horizontal axis 11 to cause a roller 23 carried by plate 18 to frictionally engage the strip 3 and press it against a die 6 where it is cut by knife 5, the device 9 then automatically being pivoted about vertical axis 17 such that the friction between the roller and the tab drags the tab out from under the die until its end is positioned in the insertion position. The guideway may extend beyond the knife 5 and die 6 and be provided with an anvil at its end, in which case the device 9 is mounted for pivotal movement through 180 DEG in each direction, and presses the outer end of the tab against 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 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 airturbulance 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 head is provided with a pivotally mounted insertion device which is automatically operable to frictionally engage a tab to be severed from the tabbing strip, press the tab against the surface of a die cooperating with the knife or against the surface of a separate anvil or the like positioned beyond the knife, and move the tab, in contact with said surface, towards a suitable point of insertion or application before moving away from said surface and returning to its initial position.

Said insertion device may be moved in a substantially vertical plane, towards and away from said surface, by a first solenoid and in a substantially horizontal plane, towards and away from the point of insertion, 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 inserter head and transmit their movement to the insertion device through small-diameter connecting rods.

For use with non-adhesive tabs the insertion device is operable to hold each tab momentarily in the insertion position before releasing the tab and swinging back but for use with adhesive tabs it is operable to hold each tab clear of the point of application and then swing it into position at the correct moment. As soon as an adhesive tab is applied 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 to the tabs.

One embodiment of the invention will be described, by way of example, with reference to the accompanying drawings in which: Figures 1 to 3 are perspective views of the outer end of a tab inserter showing an insertion device in accordance with the invention in three of its positions of operation.

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 and beneath a pivoted flap 1,shown lifted in the drawings to reveal the elements beneath it, to a rotary knife 5 which cooperates with a die 6 to sever tabs of the required length from the end of 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 strip 7 of siliconised-paper which is removed at a roller 8 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 adhere to a moving web immediately prior to a tab being severed therefrom and this requirement involves the difficulties already referred to.

In orderto overcome these difficulties and achieve accurate placement of tabs the head of the inserter is provided with a device shown generally at 9.

This device includes a substantially vertical plate 10 pivotally mounted at 11 for movement about a substantially horizontal axis on the guideway 4 and secured at 12to a rod 13 connecting itto a solenoid 14 mounted in a casing 15 beneath the guideway.

The forward end of the plate 10 carries a block 16 provided with a substantially vertical pivot 17 for the outer end of a substantially horizontal plate 18 which is secured at 19 to the forward end of a rod 20 connecting the plate to a solenoid 21 in the casing 15 and carries at its inner end, an angle member 22 in which a roller 23 is rotatably mounted.

When the feed device is operated to advance the strip 3, the device 9 is positioned with the roller 23 immediately under the die 6, as shown in Fig. 1, but separated therefrom to allow the end of the strip to pass without hindrance beneath the die. At the end of the feed step, the solenoid 14 is operated to move the plate 10 in a clockwise direction, as viewed in Fig.

1, to bring the roller into engagement with the underside ofthe strip 3 and press its upper surface against the underside of the die 6. The knife 5 is then operated through the medium of a connecting rod 24 to sever a tab 25 formed by the projecting end of the strip 3, after which the solenoid 21 is operated to swing the plate 18 in an anti-clockwise direction, as viewed in Fig. 1. This movement of the plate 18 is instrumental in swinging the roller 23 relative to the die 6, as shown in Fig. 2, and the friction between the roller and the tab 25 is sufficient for the tab to be The drawings originally filed were informal and the print here reproduced is taken from a later filed formal copy.

dragged across the under surface of the die until its end is positioned to be inserted in a stack of sheets being formed, or stuck to a moving web being wound into a roll. In the former case, the tab 25 is released immediately upon insertion by operating the solenoid 14to move the plate 10 in an anticlockwise direction about its pivot 11, but in the latter case, the momentum of the moving web is sufficlient to drag the inner end of the tab from between the roller 23 and the die 6 and the device 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 out to the position shown in Fig. 3 before applying the tab 25 to a moving web. If then, the roller 23 is coated with P.T.F.E.

or other material affording minimal adhesion, the adhesion of the tab 25 to the web will be that much greater and 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 insertion device.

In a modification (not shown) the guideway 4 may be extended beyond the knife 5 and die 6 and provided at its outer end with an anvil which cooperates with an insertion device 9 which is mounted on said outer end for pivotal movement through 180" in each direction. When a tab has been dispensed the insertion device is operated to press the outer end of the tab against the anvil and after the tab has been severed the device can be pivoted about a vertical axis into any position required for insertion or application of the tab.

Claims (1)

1. Atab inserterofthe 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 outer end of the guideway or an extension thereof is provided with a pivotally mounted insertion device which is automatically operable to frictionally engage a tab to be severed from said strip, press the tab against the surface of a die cooperating with the knife, and move the tab, in contact with said surface, towards a suitable point of insertion or application before moving away from said surface and returning to its initial position.

2. A tab inserter according to Claim 1, wherein said insertion device includes a roller, rotatable about a horizontal axis, for engaging and moving said tabs, said roller being carried by a first pivotal member rotatable about a substantially vertical axis on a second pivotal member rotatable about a substantially horizontal axis on said guideway.

3. Atab inserter according to Claim 2, wherein said first pivotal member is a substantially horizontal plate positioned below the level of said die or anvil and provided on its upper surface with a fixed mounting for said rotatable roller.

4. Atab inserter according to Claim 2, wherein said second pivotal member is a substantially vertical plate arranged on one side of said guideway and carrying a pivot for said first plate.

5. A tab inserter according to any one of Claims 2 to 4, wherein said roller is coated with a material affording minimal adhesion to the tabs.

6. Atab inserter according to Claim 5, wherein said material is P.T.F.E.

7. Atab inserter according to any one of Claims 2 to 6, wherein said first and second pivotal members are operable by solenoids connected thereto by rods extending longitudinally of said guideway.

8. Atab inserter according to any preceding claim, wherein said guideway is extended beyond said knife and said insertion device is mounted at the outer end of said guideway for cooperation with a separation anvil or the like.

9. Atab inserter according to Claim 8, wherein said insertion device is pivotablethrough 1800 in opposite directions in a substantially horizontal plane.

10. A tab inserter substantially as hereinbefore described with reference to the accompanying drawings.

New claims or amendments to claims filed on 21 Nov. 1980 Claims 8 and 9 deleted. Claim 10 renumbered as claim 8.

New claims or amendments to claims filed on 10 Dec. 1980 Superseded claims 1 New claim 1 as per attached sheet

1. Atab inserterofthe 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 ofthe guideway characterised in that the outer end of the guideway or an extension thereof is provided with a pivotally mounted insertion device which is automatically operable to frictionally engage a tab to be severed from said strip, press the tab against the surface of a die cooperating.