This application is based on and claims the priority under 35 U.S.C. xc2xa7119 of German Patent Application 198 38 494.7, filed on Aug. 25, 1998, the entire disclosure of which is incorporated herein by reference.
The invention relates to a method and an apparatus for producing multi-layer hygiene products from various generally web-shaped starting materials forming the individual layers of the finished products, whereby the starting materials are supplied from material supply stations and processed in processing stations to form the finished products.
Methods and apparatus of the above mentioned general type are known in the art and are used for producing feminine hygiene pads, liners and shields, sanitary napkins, incontinence pads, liners, shields, panties, and the like, as well as baby diapers and the like, for example. Such modern hygiene products of this type generally comprise several parts and several layers that are connected together in a sandwiched or layered structure. For this purpose it is typical to supply narrow webs or bands of various starting materials from large supply rolls to the actual processing stations in which the starting materials are processed in a suitable manner to form the finished products.
Generally, the supply roll arrangements for supplying the web-shaped starting materials are arranged above the processing stations so that they are easily accessible, and so that successive web-shaped materials can be supplied and seamlessly spliced into the processing sequence from new supply rolls without problems when a prior supply roll has been exhausted. Although the known arrangements with the supply rolls above the processing stations are made as compact as possible, these known arrangements are still often more than 15 meters and up to 20 meters long and very tall.
Generally, the above mentioned apparatus are extremely noisy during operation. In fact, they generate such a level of noise that they must be enclosed in order to reduce the externally emitted noise level. Due to the large size of the overall apparatus arrangement, the noise abatement enclosures or housings are also very large and become inefficient and expensive. Moreover, since the supply stations as well as the processing stations must be housed within the enclosures in the prior art arrangements, the enclosures must have large access doors or flaps through which empty supply rolls may be replaced by new full supply rolls. In view of the high operating speed of the modern apparatus of this type, the material supply provided by the supply rolls is relatively quickly exhausted. Thus, after a relatively short time it will again be necessary to open the enclosure access doors in order to carry out another replacement of the now-empty supply rolls. This, of course, leads to the undesirable emission of noise, and extra complexity and extra work steps in the overall operation of the apparatus.
During each exchanging of the supply rolls it is necessary to temporarily reduce the operating speed of the entire apparatus, to ensure a problem-free splicing of the head or lead end of the web-shaped material of the respective next supply roll onto the tail end of the material supplied by the previous, almost-empty supply roll. Nonetheless, it remains necessary to remove or reject and then dispose of or recycle and reprocess a certain number of the products produced during the transition period when a supply roll exchange is carried out, because these products are likely to have defects resulting from the switch and splicing of the supply material.
In view of the above, it is an object of the invention to improve an apparatus and a method for producing multi-layer hygiene products, such that the apparatus can operate at the highest possible operating speed and output capacity for the longest possible periods of time without slow-downs or interruptions, whereby it is necessary to utilize material supply rolls having the largest possible diameter. Furthermore, it is an object of the invention to minimize the waste and reject rate of products and of the various starting materials per work shift. Also, the manpower necessary for operating and monitoring the apparatus should be as low as possible. The invention further aims to avoid or overcome the disadvantages of the prior art, and to achieve additional advantages, as apparent from the present specification.
The above objects have been achieved in a method and an apparatus for producing multi-layered hygiene products, according to the invention, wherein plural starting materials which are generally in a web shape are supplied from material supply stations to a plurality of processing stations in which the starting materials are processed as required, e.g. by being embossed, supplied with an adhesive, bonded together, cut and folded to appropriate sizes and shapes, and the like, in order to form the finished hygiene products. Particularly according to the invention, the at least one processing station used for producing the finished products is spatially separated from the at least one material supply station by respectively arranging the processing station and the supply station in separate parallel planes. More particularly, these separate parallel planes, namely a processing plane and a supply plane, are respective vertical planes that are spaced apart from each other in a horizontal direction. Thus, the one or more material supply stations and the one or more processing stations are arranged laterally next to one another with a passage aisle or alley therebetween, in a preferred arrangement.
Basically according to the invention, at least one, but preferably as many as possible or all of the material supply rolls of the supply station are arranged on the supply plane which is separate and parallel relative to the processing plane on which are arranged the processing stations serving for the production of the hygiene products. By separating the supply rolls from the processing stations in this manner, it is possible to provide a noise abatement enclosure or housing around the noise-generating processing stations, whereby this enclosure or housing substantially encloses the entire processing stations continuously during the operation of the apparatus. In this context, xe2x80x9csubstantially enclosingxe2x80x9d means enclosing a predominant portion (e.g. at least 90%) of the top and all sides of the processing equipment.
On the other hand, the supply stations including the supply rolls typically generate a very low level of noise, and so these supply stations do not need to be enclosed for noise abatement purposes at all. Instead, only simple worker safety enclosures or guards are provided around the supply stations for the protection of the operating personnel. By thus separating the supply stations from the processing stations, and keeping the supply stations outside of the noise abatement enclosure of the processing stations, it is no longer necessary to repeatedly open the noise enclosure for the purpose of switching supply rolls. Also, the noise abatement enclosure can be made smaller and thereby more effective for its noise abatement purpose as well as more economical.
Moreover, with the present inventive arrangement, the supply rolls arranged on their own separate supply plane can be made larger than typical prior art supply rolls, because these supply rolls do not need to fit inside a noise abatement enclosure. In this manner, the larger supply rolls provide a longer continuous supply of material, and the operating time during which the apparatus can be operated at the highest output speed between exchanges of the supply rolls can be increased. Consequently, it is possible to reduce the amount or rate of reject products and also to increase the production output per work shift, because the apparatus suffers less down time and slow-downs due to supply roll exchanges.
These benefits are particularly achieved in connection with a complete separation between the processing plane on which the processing stations are arranged and the supply plane in which the starting material is stored on respective supply rolls of the supply stations. In other words, preferably all of the various material supply arrangements (including supply rolls supplying web-shaped materials and other supply means supplying non-web materials) included in the apparatus are arranged together on the supply plane, and all of the processing equipment is arranged together on the processing plane.
It is further advantageous if the starting material is guided generally along or near the floor, from the supply plane to the processing plane. This can be carried out in a supply channel or under a floor platform arranged between the supply plane and the processing plane. It should also be understood that such an advantageous arrangement is not limited to the supply of web-shaped starting materials. To the contrary, starting materials that are not web-shaped also can be transported along or near the floor from the supply plane to the processing plane through an appropriate channel or transport arrangement such as a conveyor arrangement.
Nonetheless, the invention is not limited to a transport of the starting material along or near the floor. Instead, the starting material can be transported overhead or along or near the ceiling for example, between the supply plane and the processing plane.
Various types of starting materials, including starting materials that are not in a web-form and that are therefore not stored on supply rolls, can be supplied from appropriate supply stations that are also arranged on the supply plane. Such non-web-shaped starting materials include flaky or flocculent materials, super absorbent materials comprising absorbent swelling substances based on acrylic or cellulose materials for example, deodorant substances, odor blocking or masking substances, binders, glues and/or adhesives, or the like.
For supplying web-shaped starting materials from supply rolls, it should be noted that the supply rolls themselves can be arranged either parallel or perpendicular relative to the supply plane and relative to the processing plane, with suitable transport and guide arrangements so that the web-shaped starting material can be rolled from the supply roll and then driven and deflected as necessary to be supplied from the supply roll to the processing stations in the processing plane.