EP2366555B1 - Device for applying adhesive to the back of a book block - Google Patents

Description

The invention relates to a device for applying adhesive to the book block spine of a guided past in a conveyor block book block of folded signatures and / or single sheets according to the preamble of claim 1.

In the production of buchbinderischen end products that have a book block, this is initially composed of individual folded sheets and / or single sheets, then processed on the book block back by milling tools or thread stitched, and finally connected with an adhesive, possibly even an envelope or a Fälzel am The book block back is glued on. The book block is clamped laterally in a conveyor for applying the adhesive with downwardly projecting block back and passed along the back of a stationary adhesive applicator.

Are known Walzenleimwerke, see [Industrial Binding; Dieter Liebau, Inés Heinze; 2nd edition 2001; Publisher Profession + School, Itzehoe; Page 284f], with two successively arranged, immersed in an adhesive tank application rollers that roll through the concurrent to the block conveying direction rotation on the book block back while transferring the adhesive to the back. The applied amount of adhesive or the adhesive layer thickness is determined by an adjustable at a distance from the applicator roll doctor. An order length can be defined by appropriately closing and opening this delivery gap, so that in particular a defined head and / or foot-side end portion of the block back can be kept free of adhesive.

The adhesive stored in the open adhesive tank is subject to relatively rapid decomposition and / or curing due to its relatively large atmosphere-contacting surface, the air entry of the rotating applicator rollers, and the constant circulation of adhesive on both sides of the block spine on the applicator rollers , The resulting contamination of the adhesive leads to a deterioration of the adhesive properties and produces voids in the adhesive layer on the applicator roll when adhesive crumbs settle in front of the squeegee. This applies in particular to the irreversibly curing adhesives, such as dispersion and polyurethane (PUR). The adhesive pool must therefore be cleaned frequently. Not inconsiderable amounts of adhesive are disposed of.

From the US 5,417,797 A an applicator for PUR adhesive is shown, which has a staff on the circumference of the applicator, upwardly open doctor box. Between stationary side walls there is a pivotally mounted rear wall, which has a squeegee arranged at the lower outlet of the squeegee and can be pivoted by an actuating device into a closed position and an adjustable open position of the squeegee. In the doctor box, only a relatively small amount of glue is stored. Controlled by a level control supplied PUR adhesive flows through the inclined rear wall to the outlet and mixes with adhesive which passes back through the applicator roll back into the basin or stripped by the spinner roll to level the job back from the block back, so again the risk the decomposition and / or curing of the adhesive consists.

The invention has for its object to provide a device for applying adhesive to the book block spine of a guided past in a conveyor book block of folded signatures and / or single sheets according to the preamble of claim 1, which allows a reliable and proper application of the adhesive and at the accumulated adhesive waste is minimized.

This object is achieved in that at least one side wall of the doctor box is adjustable according to the block thickness of the book block to be glued in the axial direction of the applicator roll. The adhesive layer removed from the applicator roll from the doctor box is only applied to the applicator roll as wide as required by the thickness of the block back to be glued. Additional adhesive is not discharged and circulated and therefore does not come into unnecessary contact with the atmosphere. By adjusting the at least one side wall according to the application width or block thickness, the adhesive volume stored in the doctor box is also adapted to the respective delivery volume flow, which is largely determined by the block thickness. The risk of decomposition and / or curing of the adhesive is significantly reduced by these two effects, which is why the device according to the invention is preferably suitable for the processing of moisture-sensitive polyurethane adhesives or in a doctor blade heated dispersion. By applying heated dispersion, a required bond strength can be achieved more quickly without having to use infrared or high frequency drying. The cleaning cycles can not only be extended with the device according to the invention, it must be disposed of even a small amount of adhesive ..

The sealing of the doctor box can by an elastic, between cheeks of the side walls clamped, sealing against the applicator roll and the rear wall Seal made of PTFE. PTFE seals have a low coefficient of friction with abrasive seal against the rotating applicator roll and not only have non-stick properties but are also resistant to the adhesives used. The clamping between the cheeks, worn seals can be easily replaced.

In the outlet of the doctor box possibly in the width swelling adhesive and / or laterally pushed away from the block back adhesive can be returned to the doctor box, if the side walls have an opposite to the direction of rotation of the applicator roll opening bevel.

The adjustment of the at least one side wall can be effected in a simple manner in that the side wall is guided on an adjustable according to the block thickness guide bar of the conveyor, so that a separate adjustment can get away with.

A detrimental air entry can be avoided that the adhesive supply takes place below the level of adhesive present in the doctor box.

Adhesive possibly dripping off the application device can be reliably received by a collecting trough arranged below the at least one application roller. The adhesive waste can easily be disposed of via a silicone-containing paper liner from the drip tray. Contamination of the held in the doctor box adhesive can be avoided that adhesive, which is stripped from one of at least one applicator roll downstream spinner roller from the book block back, is derived via a baffle in the drip pan.

In a preferred embodiment, the doctor is formed by a clamped in a groove of the rear wall, exchangeable application tongue made of spring steel. A worn squeegee can be easily replaced or moved in the groove to set its distance to the applicator roll. In addition, a respective in their material properties to the adhesive viscosity to be processed doctor can be used. Furthermore, the squeegee can be adjusted by adding one or more support tongues. Preferably, the application tongue is assigned a set back from the applicator roll drip tongue, which allows a reaction-free dripping of possibly flowing over the application tongue adhesive.

For adjusting the distance of the doctor blade to the applicator roll, be it for the employment of the doctor box and in particular the doctor blade to the application roller in the course of a basic setting or for clockwise opening and closing of the doctor during operation, it is provided that the rear wall of the doctor box is movable relative to the applicator roll and the side walls , A simple construction results if, for the distance adjustment of the doctor, the entire doctor box is movable relative to the applicator roll. The doctor box and the applicator roll can be conveniently cleaned when the doctor box is movable away from the applicator roll and / or removable.

Fig. 1

in einer Vorderansicht eine Klebstoffauftragsvorrichtung für einen Klebebinder mit Transportklammern;

Fig. 2

die Klebstoffauftragsvorrichtung aus Fig. 1 in einer Seitenansicht;

Fig. 3

die Klebstoffauftragsvorrichtung gemäß Seitenansicht der Fig. 2 für einen Klebebinder mit einem Klemmkettenförderer;

Fig. 4

einen Ausschnitt der Klebstoffauftragsvorrichtung aus Fig. 1 in einer Draufsicht;

Fig. 5

ein Detail von der Rakelaufnahme in der Klebstoffauftragsvorrichtung aus Fig. 1.

The invention will now be explained in more detail with reference to the drawing. Show it

Fig. 1

in a front view of an adhesive applicator for an adhesive binder with transport brackets;

Fig. 2

the adhesive applicator off Fig. 1 in a side view;

Fig. 3

the adhesive application device according to side view of Fig. 2 for an adhesive binder with a Klemmkettenförderer;

Fig. 4

a section of the adhesive application device Fig. 1 in a plan view;

Fig. 5

a detail of the doctor blade receptacle in the adhesive application device Fig. 1 ,

The adhesive application device 1 is intended for an adhesive binder, are bound in the folded sheets and / or cut sheets book block 2 in the back 2 a. The book blocks 2 are transported in brackets 3 of a transport device in the conveying direction F. When passing the adhesive applicator 1, the downwardly projecting spine 2 a are glued.

The adhesive application device 1 consists of two successively arranged, parallel to the conveying direction F rotating applicator rollers 4, on whose lateral surface in each case a doctor box 7 is employed with adhesive 6 located therein. The applicator rollers 4 take with their lateral surface adhesive 6 and transfer it in a rolling motion on the book block back 2 a. The two layers applied by the two applicator rollers 4 adhesive layer on the book block back 2 a is finally smoothed by a counter-rotating spinning roller 5.

The respective adhesive layer 11 to be transferred to the applicator rollers 4 is determined by a squeegee 10 which is arranged at a distance s from the applicator roller 4 and which is arranged at the lower outlet of the doctoring box 7. An order length can be defined by appropriately closing and opening this delivery gap. This is useful if the head and foot end portions of the book block back 2 a should not be glued.

The upwardly open doctoring box 7 consists of a rear wall 8 and side walls 9.1, 9.2, each having an elastic, between cheeks 12 clamped against the support roller 4 and the rear wall 8 sealing sealing element 13 preferably made of PTFE. The rear wall 8 is pivotally mounted in the frame-side bearing blocks 16 via holders 14 and a respectively received therein, parallel to the applicator roll 4 axis 15. By means of a rotatable eccentric shaft 18 determined by a servomotor 19, the outlet-side end of the rear wall 8, at which the doctor blade 10 is located, can be changed at a distance s from the applicator roller 4 for opening and closing the doctor blade 10 in a timely manner. Alternatively, the doctor box 7 can be guided for pivoting away from the applicator roll 4 in linear guides.

According to the invention, a side wall 9.2 is adjustable according to the block thickness D of the book block 2 to be glued in the axial direction of the applicator roll 4 so that the outlet width of the adhesive layer 11 removed from the applicator roll 4 from the doctor box 7 is equal to the block thickness D of the block back 2 a to be glued already explained in the description of benefits. The side walls 9.1, 9.2 have at the inlet end of the doctor box 7 opposite the direction of rotation of the applicator rollers 4 opening bevels 9 a, which in the outlet of the doctor box 7 possibly in the width of swelling adhesive and / or from the book block back 2 a laterally pushed away adhesive back into the Doctor box 7 is returned.

Like from the Fig. 1 . 2 and 4 can be seen, the side walls 9.1, 9.2 are each attached to a boom 20 a of a guide block 20 which is guided on a parallel to the applicator roll 4, fixed to the rear wall 8 guide rail 21 slidably. Because in the exemplary embodiment Fig. 1 and 2 a block edge is stationary, the first side wall 9.1 is fixed with its guide block 20 on the guide rail 21. The second side wall 9.2 is adjustable via an adjusting spindle 22 and an associated adjusting nut 23 in the arm 20 b of the guide block 20. For an automated adjustment, a servo motor 24 connected to the adjusting spindle 22 is provided.

In Fig. 3 a modified adhesive applicator for an adhesive binder with a clamping chain conveyor 25 is shown. The book blocks 2 are between two synchronously driven, clamping plates 26 having conveyor chains 27 a, b clamped, which are guided symmetrically on block center 2 b adjustable guide bar 28. Attached to the guide beam 28 drivers 29 engage the upwardly extended arms 20 a of the guide blocks 20 so that when thickness adjustment of the Klemmkettenförderers 25, the side walls 9.1, 9.2 are equally adjusted automatically with and the discharged width of the adhesive layer 11 is always equal to the book block thickness D.

The doctor box 7 is filled with adhesive 6 by a hole 30 located below the adhesive level in the rear wall 8. Harmful air entry is thereby avoided. The bore 30 is connected to a hose 31 of an adhesive supply, not shown, the fresh adhesive 6 controlled by a level sensor 32 pumps quasi from below into the doctor box 7.

For processing hot adhesive 6, such as PUR or hotmelt, the rear wall 8 of the doctor box 7 is equipped with heating cartridges 33 and also a heated applicator roll 4 is provided. This also dispersion can be processed, which is heated immediately before application to a maximum of 100 ° C. By applying heated dispersion, a required bond strength is achieved more quickly, without the need for infrared or high-frequency drying. Cracking of the dispersion is avoided because no excess already heated adhesive 6 is returned to the doctor box 7.

Below the application rollers 4, a collecting tray 34 designed with silicone-containing deposit paper is provided, in which possibly adhesive dripping from the application device 1 can be collected. The stripped from the spinner roller 5 from the book block back 2 a adhesive can also be supplied via a discharge plate 35 of the drip pan 34 to avoid possible contamination by recycled into the doctor box 7 adhesive. Very well, as is common in the known Walzenleimwerken, the adhesive derived from the spinner roll 5 in the doctor box 7 or a reservoir of the adhesive supply are returned.

The collecting trough 34 also serves to receive the adhesive 6 stored at the end of production in the doctoring boxes 7 as well as the cleaning liquid used in the final cleaning of the adhesive application device 1. Due to the small storage volume of the doctor box 7 only a very small amount of adhesive must be disposed of as waste.

The solid caking of adhesive is prevented by non-stick coatings on the adhesive-contacting components of the adhesive applicator 1. The cleaning is facilitated by the fact that - by releasing the bearing blocks 16 from the frame walls 17 of the adhesive applicator 1 - the doctor boxes 7 can be removed from the applicator rollers 4 total.

The squeegee 10 is as out Fig. 5 can be seen from a composite of an application tongue 36, a set back from the applicator roll 4 drip tab 37 and a support tongue 38 which are clamped together in a groove of a arranged at the outlet end of the rear wall 8 squeegee receptacle 39 and made of spring steel in different lengths and thicknesses are. By combining different tongues 36, 37, 38, a doctor blade 10 can be configured according to the properties of the respective adhesives 6 to be processed, which differ mainly in their viscosity from each other. Worn application tongues 36 can be exchanged. The drip tab 37 allows a reaction-free dripping of possibly on the application blade 36 effluent adhesive. 6

In the case of the adhesive application device 1 shown in the figures, a doctor blade box 7, which is pivotable in its entirety, is provided. Nevertheless, the invention can also be embodied in that the side walls 9.1, 9.2 are adjustable on a rail fixed relative to the applicator roll 4, whereby the side walls 9.1, 9.2 having a complementary radius to the applicator roll 4 can be set exactly against the applicator roll 4. The rear wall 8 could then be moved within the scope of the elasticity of the sealing element 13 used in the side walls 9.1, 9.2 for opening and closing the doctor blade 10, without the adhesive 6 exiting. Or the rear wall 8 is fixed at least during operation and only the squeegee holder 39 is moved to open and close the squeegee 10.

Furthermore, the invention can also be embodied in that a doctoring box 7 fixed at least during operation is used, in which the doctor blade 10 is set at a distance s from the applicator roll 4 for an uninterruptedly thick adhesive layer 11 on the applicator roll 4.

Claims (12)

1. A device (1) for applying glue (6) on the book block spine (2a) of a book block (2) that consists of gathered signatures and/or single sheets and is transported past the device by a transport device (F),

   • with at least one application roller (4) that is rotationally driven in the same direction as the book block (2) and in rolling contact with the book block spine (2a) with its circumference,

   • with a blade box (7) featuring a rear wall (8) and sidewalls (9.1, 9.2), wherein said blade box is screwed down on the circumference of the application roller (4) and forms a receptacle for liquid glue (6) together with the application roller,

   • with a doctor blade (10) that is provided on the end of the rear wall (8) of the blade box (7) and can be adjusted with respect to its distance (s) from the application roller (4) in order to thereby define the thickness of the glue layer to be transferred onto the book block spine (2a), and

   • with a glue supply (30, 31) for supplying liquid glue (6) to the blade box (7),

   characterized in

   • that at least one sidewall (9.2, (9.1)) of the blade box (7) can be adjusted in the axial direction of the application roller (4) in accordance with the block thickness (D) of the book block (2) to be glued.
2. The device according to claim 1, characterized in that the sidewalls (9.1, 9.2) feature an elastic sealing element (13), preferably of PTFE, that is clamped between flanges (12) and forms a seal relative to the application roller (4) and the rear wall (8).
3. The device according to claim 1 or 2, characterized in that the sidewalls (9.1, 9.2) feature infeed chamfers (9a) that open opposite to the rotating direction of the application roller (4).
4. The device according to one of claims 1-3, characterized in that the at least one adjustable sidewall (9.2, (9.1)) is guided on a guide beam (28) of the transport device (25) that can be adjusted in accordance with the block thickness (D).
5. The device according to one of claims 1-4, characterized in that the glue supply (30, 31) takes place below the glue level in the blade box (7).
6. The device according to one of claims 1-5, characterized by a collecting tank (34) that is arranged underneath the at least one application roller (4).
7. The device according to claim 6, characterized in that glue stripped off the book block spine (2a) by a spinner roller (5) arranged downstream of the at least one application roller (4) can be diverted into the collecting tank (34) by means of a deflector plate (35).
8. The device according to one of claims 1-7, characterized in that the doctor blade (10) is formed by an exchangeable application blade (36) mounted in a groove of the rear wall (8, 39).
9. The device according to claim 8, characterized in that a drip blade (37) is assigned to the application blade (36).
10. The device according to one of claims 1-9, characterized in that the rear wall (8) of the blade box (7) can be moved relative to the application roller (4) and the sidewalls (9.1, 9.2) in order to adjust the distance of the doctor blade (10).
11. The device according to one of claims 1-10, characterized in that the entire blade box (7) can be moved relative to the application roller (4) in order to adjust the distance of the doctor blade (10).
12. The device according to one of claims 1-11, characterized in that the blade box (7) can be moved away and/or detached from the application roller (4) in order to clean the application device (1).

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