METHOD AND APPARATUS FOR APPLYING A PROTECTING FILM TO BOOKS AND BOOKLETS

Abstract: Method and apparatus for applying a protecting film to books or booklets comprising a conveyor belt (3) leading the book or booklet (5, 5', 5'') one by one with their back turning toward the middle of the adhesive side of a piece of cut off film (22) held in a stretched position between two rolls (20, 21) rolling the film onto the book or booklet. A length of film (12) is led down over a height adjustable roll (20), a cover film (11), if any, is removed, whereafter a piece of film is cut off by cutting tools (16, 18) in accordance with the pre-measuring of the dimensions of the book. Hereby is achieved an automatizing of the hitherto applied manual process of applying a protecting film to books or booklets. By the automatizing the speed of applying such a film is increased considerably, and a perfect and even film application is achieved, free from air bubbles, the film being rolled onto both sides of the book from its back toward the edges.

Description: METHOD AND APPARATUS FOR APPLYING A PROTECTING FILM TO BOOKS AND BOOKLETS. The invention relates to a method and an apparatus for applying a protecting film to books or booklets. Books or booklets often used, or often read or skimmed through by many people, are often protected by some kind of extra binding. To avoid providing the extra cover with the text from the actual cover, transparent paper or plastic material is used for the extra cover. Moreover, certain types of booklets, such as cartoons for instance, have a cover that is not strong enough to withstand frequent use, and where such booklets are lend from the library or reading room, the cover will quickly tear. They are therefore nearly always protected by a transparent and often self-adhesive protecting film. It is hard manual work to apply a protecting film to books, especially where the self-adhesive sort is applied, which is often desirable, as this type of film is highly resistant to wear and tear. First, a piece of film of correct size is cut, and a cover film on the adhesive side is then removed. The film is then applied to the book. The self-adhesive films applied are highly adhesive, and they should thus be placed correctly in the first attempt, as it is impossible to remove the film without damaging the book. It is also a problem to prevent air from being trapped at points between the film and the original binding of the book or booklet. which trapped air will cause bubbles in the cover. Manual application of a self-adhesive protecting film to a book or booklet, whereby air bubbles are completely avoided, requires experience and dexterity. An experienced worker may thus at a maximum apply thirty books or booklets with protect¬ ing film per hour. Object of the invention is to describe a method and an apparatus for applying a protecting film to books or booklets in order that a film is applied perfectly, but at the same time in order that the speed of application is increased considerably. This is achieved by proceeding as related to in the characterizing part of claim 1, e.g. by using an apparatus as related to in the characterizing part of claim 4. The manual process is thereby automatized, whereby an apparatus may apply film to books at a rate of 300 books per hour. By using rolls applying the film on the outer sides of the book or booklet, a smooth and even application, totally free from air bubbles, is always obtained. By using an apparatus as related to in the characte- rizing part of claim 5, it is achieved that the apparatus may apply film to books or booklets of varying thickness, making any changes in the appara¬ tus as well as adjustments for the thickness and other dimensions of the book unnecessary. By proceeding as related to in the characterizing part of claim 2, e.g. by using an apparatus as related to in the characterizing part of claim 6, .it is achieved that the same means may be applied both for holding the prepared piece of film as well as for applying the piece of film to the next book. The whole process of applying the film is fully automatized, in that the apparatus measures and cuts off a piece of film of correct size depend¬ ing on the thickness as well as the size of the book or booklet. Where a flap is required, and it usually is, the film is measured with the required excess measure, e. g. 2 x 15 mm for the edges of the book opposite the back, as flaps normally are not required for the edges of the book standing at right angles to the back of the book. The flap is folded manually after the application of the film is completed. By proceeding as related to in the characterizing part of claim 3, e.g. by using an apparatus as related to in the characterizing part of claim 7, a film may also be applied to books or booklets, having a highly sensitive cover. Where a film is to be applied to e.g. hardbacks, where the cover is not scratchproof, it is not sufficient merely to convey and position the books on an ordinary conveyor belt, as small sand or other dirt particles may cause scratches in the cover. By using an air cushion according to the invention, scratches and other damages to the cover caused prior to the application of a protecting film, are completely avoided. The apparatus for applying protecting films is primarily designed as related to in the characteri¬ zing part of claim 8. The apparatus may thus in a simple manner be adjusted for books or booklets of varying thickness. The apparatus is primarily designed in order that adjustment of height takes place according to the thickness of the next book. The invention is explained in more detail with reference to the drawing, which is an outline of a vertical plane section through an embodiment of the invention. In the drawing 4 is a table or a similar machine frame carrying the whole of the film applying appara¬ tus. On the left a case with books 1 is shown, which case is designed in order that it may hold books of varying sizes. The case is of a generally known sort and thus need be described in no further detail. From the bottom of the case, the books are delivered one by one by a generally known delive¬ ry device to an endless conveyor belt 3, always moving in the direction indicated by arrows. The books are placed with their backs facing to the right and are delivered to the belt 3 in the same position. It is therefore necessary that the books 1 are always placed in the case with their back in a certain direction, but it is irrelevant whether the book has its front up or down. When a book or a booklet is delivered, it meets a thickness sensing device 2 measuring the thickness of the just delivered book. The conveyor belt 3 is supplied with a number of holes or nozzles 14 for compressed air in order to create an air cushion between the book 5 and the belt 3. Thus, the book 5 may be moved or pushed to its correct place along the belt, without dirt, sand or unevennesses on the belt scratching the book cover. A micro switch or another type of sensing device 6 acts, as soon as a book 5 passes, thus actuating an air cylinder 26 controlling a lateral steering control placing the book 5 correctly on the belt; the length of the back of the book is measured simultaneously. Further to the front of the belt 3 is another micro switch or another type of sensing device 9. The sensing devices 6 and 9 are used for controlling the driving motor of the conveyor belt 3 in order that the books 5 and 5' are conveyed at a suitable pace and keeping a suitable distance. The sensing devices 6 and 9 are moreover applied for measuring the width of the book. The width of the book ma also be established by measuring the book case delivering the book to the belt 3. When a book 5' 1 has reached the actual application position, the film device has been prepared. From a store roll a length of film 12 with cover film is led to a main roll 20 with a unilateral direction of rotation as shown. The length of film 12 immedi¬ ately meets a pulling roll 15 pulling the length of film 12 forward and delivering the cover film 11 to a store roll. Arrows indicate the direction of motion of both the length of film 12 and the cover film 11. The protecting film is led further along by a roll 16, which moreover cuts the edge of the film to the correct width in accordance with the earlier mentioned measuring of the height of the book. By a leading roll 17 the film is led through an opening (not shown) in the table 4 down toward a drawing and holding roll 21. The holding roll 21, which may be a suction roll, catches the edge of the film and holds and draws this, the roll 21 at this stage having the same direction of rota¬ tion as the main roll 20. In accordance with the result of the pre-measuring of the width and thick¬ ness of the book, a cutting tool 18 is operated in such a manner that a piece of film 22 of suffici- ent size for the book 5 11 is cut off, which book has now reached the film application device. The prepared and clean cut piece of film 22 is now held and stretched between the rolls 20 and 21 both standing still, the holding roll 19 pressing the film toward the roll 20, and the film being sucked onto the roll 21. The film is now ready for application, in that the adhesive side turns toward the back of the book 5' ' now to be applied with film. The book 5' 1 is led toward the film by the conveyor belt 3 and between the rolls 20 and 21, of which the latter is now driven in the opposite direction of rotation, whereby the piece of film 22 is rolled onto the book 5' 1 from its back toward the edges. Another conveyor belt 8 now takes over and conveys the book 5' ' ' to a position 5' ' ' ' , where the book is delivered for further treatment, such as manual folding of excess film along the edges of the book opposite the back. The main roll 20 with the auxiliary rolls 15, 16, 17, and 19 as well as the cutting tool 18 are mounted on a holder 10, which may be turned around its centre of suspension 25, whereby the position of all the mentioned parts may be changed jointly, as indicated by the double arrow next to the holder 10. The distance between the main roll 20 and the holding roll 21 is thus controlled by raising and lowering the holder 10. The holder 10 is raised and lowered by means of an air cylinder 13 with a piston catching the holder 10 by means of an arm. The distance between the rolls 20 and 21 is adjusted according to the thickness of the book in order that the rolls always roll the piece of film 21 onto the book 5' ' exerting a certain press¬ ure, irrespective of the thickness of the book. The roll distance is thus automatically adjusted to correspond with the size of the next book to be applied with film exactly. Between the table 4 or the conveyor belt 8 and the holder 10 is a micro switch 23 or a similar sensing device sensing the O-position to prevent the rolls 20 and 21 from pressing too hard against each other, when the apparatus does not apply film to a book. Below the two conveyor belts 3 and 8 there may be room for placing various auxiliaries, such as a compressed-air pump or a vacuum pump 7 with a tank for compressed-air and vacuum, respectively, and one or more cases 24 with the necessary equipment for controlling and adjusting each operation of the apparatus. The driving motors for the conveyor belts may moreover be placed here. The individual rolls and auxiliary rolls may be driven by small electric motors or by compressed-air motors. The rolls 15, 16, 17, and 19, and possibly also the rolls 20 and 21 as well as the cutting tool 18 are constructed in such a manner that the highly adhesive film does not adhere, as they may be provi- ded with Teflon or a similar rejecting coating. The rolls 20 and 21 are primarily rubber rolls. The control case 24 controls the various operations of the apparatus in a generally known manner by sensing the position and size of the books, the controlling and adjusting taking place in a generally known manner by means of electric components or compressed-air components.

Claims: C L A I M S 1. Method for applying a self-adhesive protecting film to a book or a booklet, c h a r a c t e r i - z e d in that the book or booklet in its closed position and with its back pointing forward is led toward a cut off piece of protecting film with its adhesive side toward the book or booklet, said book or booklet and the film then being led between two rolls in order that film is rolled onto both sides of the book or booklet simultaneously. 2. Method according to claim 1, c h a r a c t e ¬ r i z e d in that the two rolls rolling the film onto the book or booklet are also applied for keeping the film stretched prior to it being applied. 3. Method according to claim 1, c h a r a c t e ¬ r i z e d in that the book is essentially conveyed on an air cushion until it meets the film. 4. Apparatus for performing the method according to claim 1, c h a r a c t e r i z e d in that the apparatus has means of conveyance (3, 14) design- ed so as to convey the book or booklet (5, 5' , 5* ' ) with its back toward the middle of the adhesive side of a piece of cut off film, which is kept in a stretched position by holding means (20, 21), and so as to lead the book or booklet between a pair of rolls (20, 21) designed so as to be able to roll the film onto the book or booklet, said rolls (20, 21) rotating and pulling the book or booklet forward between them. 5. Apparatus according to claim 4, c h a r a c t e ¬ r i z e d in that one of the rolls (21) in the operating position of the apparatus is situated immediately below a feeding device for the means of conveyance (3, 14), that the other roll (2 " 0) is placed above the former roll and attached to a roll holder (10), which is adjustable for height depending on the thickness of a book or booklet, and in that the apparatus has means for measuring the thickness of a book or booklet. 6. Apparatus according to claim 4, c h a r a c t e ¬ r i z e d in that the apparatus has means for conveying a length of film (12) down over the height adjustable roll (20), that any cover film (11) is removed , that a piece of film is cut off by the cutting means (16, 18) in accordance with the pre-measuring of the dimensions of the book, and whereby the height adjustable roll (20) and the bottom roll (21), which primarily is a suction roll, are designed in order to be able to keep said piece of film (22) in its stretched position, whereby the bottom roll (21) is reversible. 7. Apparatus according to claim 4, c h a r a c t e ¬ r i z e d in that the means of conveyance comprise an endless conveyor belt (3) and above this an air cushion formed by a number of nozzles or holes (14) for compressed air. 8. Apparatus according to claims 4-6, c h a r a c ¬ t e r i z e d in that the height adjustable roll holder (10) also carrying the cutting means (16, 18) is adjustable for height by means of a working I 11 cylinder (13) acting against the own weight of the roll holder (10).

Inventors: ANDERSSON DENNIS ERIK, ANDERSSON, DENNIS, ERIK
Applicants: ANDERSSON DENNIS E, ANDERSSON, DENNIS, ERIK
Application year: 1985
Main classification: B42C11
IPC codes: B42C15