Apparatus and method for forming a block of folded material

Abstract

The invention includes an apparatus for forming a block of folded material, and a method for forming a block of folded material. The inventive apparatus includes a folder for folding a web onto a block, a holder holding an end of the web from a bottom layer of the block. The apparatus further includes a cutter for providing an end portion from an uppermost layer of the block. The inventive method includes the steps of folding a web onto a receiving element until a portion of the web forms a folded block of a preselected height, and feeding the uppermost web layer to a cutter. The inventive method further includes cutting an uppermost web layer to form an end portion, and laying the end portion from a bottom layer of the block at least partly on top of the block.

Description

BACKGROUND AND SUMMARY OF THE INVENTION

[0001] This present invention relates to an apparatus and a method for forming a block of folded material. Preferably, the apparatus and method will be used in the production of festooned packages that are commonly used in the hygienic industry, which commonly uses a web of non-woven fabric or airlaid material.

[0002] International document WO 98/58864 shows a package of festooned web material that is cut into several stacks. As shown, the end of each stack is accessible so that it can be connected to the end portion of another stack. A strip portion is pulled from underneath the stack in order to provide a free end from the bottom of the stack. This operation generally had to be carried out manually, requiring someone to grip the end portion and arrange it in the preferred position. This requirement for manual handling presented a serious inconvenience, because the festooned packages are generally used in the hygienic industry. Cleanliness of materials used in this application is crucial and the elimination of manual operations is of utmost importance in order to preserve sterile and clean stacks of material. In addition, removing a strip from the bottom required flipping of the festooned block—a time consuming procedure.

[0003] The present invention provides an apparatus and a method for separating the web from a block of folded material that can be used for hygienic products. The inventive apparatus and method is more effective in handling the web after the festooning of a block is completed.

SUMMARY OF THE INVENTION

[0004] The apparatus comprises a holder for holding an end of the web from the bottom layer of the block, and a cutter for providing an end portion from the uppermost layer of the block so that manual handling of the web is no longer necessary during the entire process. The elimination of manual handling is particularly important for the production of materials that will be used in hygienic products, such as diapers and other sanitary products. Additionally, automatic handling of the web material reduces down time of the production line, thus increasing production efficiency. The apparatus also includes a holder integrated into the apparatus so that the end portion from the bottom layer can be laid on top of the block without requiring the entire block of material to be flipped.

[0005] The holder may include a roller for winding and unwinding a portion of the web. The holder allows effective handling of the web as the height of the block increases in continued folding. This allows a continuous unwinding of the end portion and prevents loose portions from protruding or hanging from the block.

[0006] The block may be formed on a receiving element which may be moved to a horizontally adjacent processing station. This movability decreases down time of the folder during the cutting operation. Alternatively, a conveyor may be used to move the block of folded material.

[0007] In order to ensure effective and accurate cutting of the web, an accurate and precise cutter is required. The cutter includes a sledge and a cutting knife movable on the sledge. The knife can be rolled on the web, engaging the sledge in order to cut the web so that the material stress is minimized during the cutting of the web material. In order to obtain a more clean cut, a clamping bar may be used to fix a portion of the web onto the sledge.

[0008] The holder may include a needle roller having protruding needles which may be inserted into the web, enabling the apparatus to handle the web without an additional clamp which would increase the risk of damaging the material. The protruding needles can be small enough in diameter to avoid any damage, since the web of non-woven or airlaid material is relatively light.

[0009] In order to prevent damage to the needles during rotation of the roller, the sledge may have notches through which the needles may pass during its rotation. The notches guarantee the needles do not contact the sledge. Contact may fracture a needle, requiring one to discard an entire block of material, as broken needle parts wedged into the block may be exceedingly dangerous.

[0010] A stripper may be positioned adjacent to the roller in order to ease the final release of the web from the roller.

[0011] The invention also includes a method for forming a block of material. According to the inventive method, the web is folded on a receiving element until the folded block reaches a desired height. Thereupon, the uppermost web layer is fed into a cutter and is then cut, whereby the end of the bottom layer is laid at least partly on top of the block.

[0012] An end portion from the bottom layer of a block may be withheld on a holder before starting to form the block, so that during the block formation, the holder can retain a sufficient part of the web to allow arrangement of the end portion at the side of the block, since the height of the block increases as the block is formed.

[0013] The block is moved in the horizontal direction so that the holding and releasing of the end portion results in laying down the end portion on top of the block. This step ensures that the end portion from the bottom of the block is laid on top of the block.

[0014] Preferably, the uppermost web layer is cut, and its end portion falls down on one side of the block. If the web is perforated to enable different lines of the web to be pulled from the festooned block, the different lines may be connected to one another. Such a splicing operation requires the connecting portions to have a preselected length, because removing the end portions from the stack could result in damage to the web.

[0015] Other objects, advantages and novel features of the present inventive method and apparatus will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a side view of the inventive apparatus according to the principles of the invention.

[0017] FIG. 2 is a side view showing a beginning of the method for providing loose end connecting portions on top of a block of folded material.

[0018] FIGS. 3-9 show various steps of the method for forming a block with loose ends arranged partly on top of the block.

[0019] FIG. 10 is a side view of the apparatus according to the principles of the invention.

[0020] FIG. 11 is a plan view showing the sledge and needle roller of the inventive apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] As shown in FIG. 1, the apparatus for forming a block of folded material includes a frame 1 to which a left folding cylinder 2 and right folding cylinder 3 are mounted. A web 4 of airlaid material passes between the folding cylinders 2 and 3. The web is gripped and folded by a rotation of the folding cylinders 2, 3 to form a block 5.

[0022] Still referring to FIG. 1, the block 5 is arranged on a receiving element 6 which is movable and preferably formed of a lifting element. The bottom layer of the block 5 has an end portion 7 which is retained by a tail holding roller 8. A sledge 9 is positioned near the upper left side of block 5. A rail system guides the sledge 9, which is moved in a horizontal direction by an electric drive system (not shown).

[0023] A needle roller 10 is positioned on the upper right side of the block. A clamping bar 11 is positioned below the needle roller 10. The clamping bar 11 is movable in a horizontal direction. Before beginning the cutting operation, the finished block 12 is removed from the position found in FIG. 1.

[0024] FIG. 2 shows the starting position for separating the web from a block 5 of folded material. Initially, the block 5 is moved horizontally from the receiving element 6, so that the block passes under the tail holding roller 8.

[0025] As shown in FIG. 3, the end portion is laid down on top of the block. The horizontal movement of the block 5 may be accomplished by either moving the receiving element 6, or by using any known conveyor means.

[0026] As seen in FIG. 4, the block 5 is moved completely beyond the tail holding roller 8, so that the end portion 7 from the bottom layer of the block 5 is arranged on top of the block.

[0027] As seen in FIG. 5, the sledge 9 begins to move under the folding cylinders 2, 3 to the clamping bar 11. Meanwhile, the tail holding roller 8 is moved in the same direction as the sledge 9.

[0028] As seen in FIG. 6, the sledge 9 moves under the needle roller 10, and the clamping bar 11 clamps a portion of the web 4 to this sledge 9 in order to cut the web 4. In this position, the needle roller rotates, thereby inserting some of the needles into the web 4. This prevents the web 4 from falling after it has been cut. Then a cutter is moved onto the sledge 9, separating the web 4. The cutter 13 may include a rolling knife in order to reduce a friction between the cutter 13 and the sledge 9. At the cutting area, the sledge is made of hardened steel in order to reduce wear.

[0029] As shown in FIG. 7, the cutting of the web 4 leaves an end portion 14. Both portions 7 and 14 are laid down, at least partly on top of the block 5, so that they can be easily detected and gripped for further processing of the folded web. The other part of the web 4 forms another end portion 7′, which is fixed to the needle roller 10. Thereafter, the sledge 9 returns from its position under the needle roller 10, to its original position, which is shown in FIG. 2.

[0030] As shown in FIG. 8, the needle roller 10 rotates about its axis in order to provide an end portion 7′ of sufficient length before beginning to fold another block. This winding process is followed by the folding cylinders 2, 3 which release a sufficient portion of the web 4. An addition, the tail holding roller 8 is moved to the left side under the needle roller 10.

[0031] FIG. 9 shows the starting position for forming a new block of folded material. The new end portion 7′ from the bottom of the new block is partly unwound from the needle roller 10, and hangs between the needle roller 10 and the tail holding roller 8. The rotation of the folding cylinders 2, 3 cause a new block to be build and the receiving element 6 moves downward. This action pulls a part of the end portion 7′ on the side of the new block. After forming the new block, the cycle repeats and the parts move to their position as shown in FIG. 2.

[0032] FIG. 10 shows the apparatus according to the principles of the invention. Note that the apparatus is shown in a position similar to the position depicted in FIG. 7. The cutter 13 has a cutting edge 21 which engages the hardened surface of the sledge 9. The web 4 is clamped between the sledge 9 and the clamping bar 11.

[0033] The needle roller 10 has recesses 22 with needle holders 16 in which needles 15 are mounted. The needles 15 are angled with respect to the radio direction. Recesses 22 may be integrated into the cylinder 17 of the needle roller 10 in order to locate the needle holders 16. As the roller 10 rotates, some needles 15 are inserted into the web. This ensures a holding of the web 4 onto the needle roller 10.

[0034] As shown in FIG. 11, the sledge 9, shown on the bottom side, may include notches 18 which are slightly wider than the diameter of the needles 15. As the needle roller 10 rotates, the needles 15 pass through the notches 18, so that the needles 15 do not contact the sledge 9. As the web 4 is held between the sledge 9 and the needle roller 10, the needles are inserted into the web 10. As evident in FIG. 11, the sledge may be driven by belts 19, 20 which engage two-toothed wheels that are driven by a motor (not shown).

[0035] A stripper 30 may be arranged at the needle roller 10 in order to ensure that the web 4 is released from the needle roller 10 when it unwinds. The stripper 30 can be made of one or more rollers (one of which is shown in phantom in FIG. 9) that guide the web in the desired direction.

[0036] Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only, and is not to be taken by way of limitation. The spirit and scope of the present invention are to be limited only by the terms of the appended claims.

Claims

1. An apparatus for forming a block of folded material, comprising: a folder for folding a web onto a block; a holder holding an end of the web to extend from a bottom layer of the block; a cutter for providing an end portion from an uppermost layer of the block.

2. An apparatus as in claim 1, wherein the holder includes a roller for winding and unwinding a portion of the web.

3. An apparatus as in claim 1, further including a receiving element on which the block is formed, the receiving element being movable in both a vertical and horizontal direction.

4. An apparatus as in claim 1, wherein the cutter includes a sledge and a cutting knife movable on the sledge.

5. An apparatus as in claim 4, wherein the cutter includes a clamping bar for fixing a web portion on the sledge.

6. An apparatus as in claim 4, wherein the holder includes a needle roller having protruding needles which are insertable into the web.

7. An apparatus as in claim 6, further comprising notches formed on the sledge, the notches being formed to allow the needles to pass through during rotation of the roller.

8. An apparatus as in claim 6, further comprising a stripper adjacent the roller, the stripper positioned adjacent the roller in order to remove the web from the roller.

9. The apparatus as in claim 1, wherein the holder is movable to put the end of the web on top of the block.

10. An apparatus for forming a block of folded material, comprising: a folder for folding a web onto a block; a cutter for providing an end portion from an uppermost layer of the block; a holder for holding an end of the web to extend from a bottom layer of the block, the holder having a roller with protruding needles which are insertable into the web; and wherein the cutter includes notches formed to allow the needles to pass therethrough when the roller rotates.

11. A method for forming a block of folded material, the folded material having loose ends accessible for connection, the method comprising the steps of: folding a web on a receiving element until a portion of the web forms a folded block of a preselected height; feeding an uppermost web layer to a cutter; cutting the uppermost web layer to form an end portion; laying an end portion from a bottom layer of the block at least partly on top of the block.

12. The method as in claim 11, further comprising the step of withholding an end portion of the bottom layer on a holder before starting to form the block.

13. The method as in claim 12, further comprising the step of unwinding the end portion of the bottom layer while forming the block.

14. The method as in claim 12, further comprising the steps of moving the receiving element in the horizontal direction, and laying the end portion of the bottom layer on top of the block.

15. The method as in claim 14, further comprising the step of cutting the uppermost web layer so that its end portion falls down on one side of the block.

16. A method for forming a block of folded material, the folded material having loose ends accessible for connection, the method comprising the steps of: withholding an end portion of a bottom layer of the material on a holder; folding a web on a receiving element until a portion of the web forms a folded block of a selected height; feeding an uppermost web layer to a cutter; cutting the uppermost web layer to form the end portion; laying the end portion from the bottom layer of the block at least partly on top of the block; unwinding the end portion of the bottom layer while forming the block; and cutting the uppermost web layer so that its end portion falls down on one side of the block.