TECHNICAL SCOPE OF THE INVENTION The present invention refers to a method, a system of mechanisms and a product where the assembly of the innerspring mattress unit is done by using mainly independent spring cores, which are adhered onto the two surfaces of non-woven or other mattress making material that cover the spring cores.

STATE OF THE ART Until recently, construction of innerspring units was based on the following : First, the spring cores that are needed for the construction of the mattresses are produced by single head production machines and are subsequently interlaced with spiral connector wires and thus comprise an integrated entity.

This innerspring mattress unit is then covered by the mattress making materials that are laid over the large surface sides and are usually connected between them on the sides through a third material entity. At the middle parts of the mattress the mattress making materials are not connected or are connected with adhesive that is sprayed over the internal surface areas with the objective to bond subsequently the spring cores.

This does not lead to successful results because a large quantity of adhesive is needed to cover a surface area of 90 mm by 90 mm in order to be able to bond the spiral connector wire that has a thickness of 2 mm.

Thus, effort is concentrated to mainly attach the mattress materials to the sides of the innerspring unit in order to achieve firm support.

The second group of innerspring mattress units includes the method with the referred as independent spring cores, which are 100% encapsulated one by one within pockets made of fabric or non woven. These spring cores are encapsulated in such a manner, so as to be in a pre-compressed state, which imparts advantages to the mattress.

The spring cores are connected between them through the fabric that separates them from the adjacent ones. Some of the inventions with the above mentioned methods are the following ones: EP0154076, EP00155158, EP00421496 and EP00304798.

There exists a method that utilizes independent spring cores but in order to achieve the firm positioning of the spring end turns on the upper and lower mattress surface it essentially abolishes the materials that are used in mattress making, such as fabric, non woven, coconut fibre, felt, foam, etc. and instead makes use of liquid polyurethane into which the spring core end turns are immersed, achieving thus firm encapsulation of the spring cores once the polyurethane solidifies.

PRESENTATION OF THE FIGURES Figure 1: Part of an innerspring mattress composed of independent spring cores with unequal distribution of the distances between successive spring cores.

Figure 2: Spring core connected to the mattress materials either by the application of adhesive onto the two end spring turns or through its attachment with metallic connector clips.

Figure 3: Creation of pre-compression in free mattress spring cores.

Figure 4: Part of an innerspring unit that is comprised of spring cores interconnected with spiral connector wires.

Figure 5: Interconnection of the end turns of adjacent spring cores via the mattress materials with the utilization of a connector clip.

Figure 6: Part of a machine complex that produces and thermally processes the spring cores of a mattress using a multi-head complex that assembles mattresses comprised of independent spring cores and creation of pre- compression.

REVELATION OF THE INVENTION The objective of this invention is to construct a new product that contains independent and pre-compressed spring cores, by employing a new method that does not encapsulate the spring cores within pockets as other methods do and without immersing the two free end turns of the spring cores into liquid media that with time solidifies and achieves attachment. Only with the usage of typical mattress materials we attain the complete independence of the spring cores between them, as well as the pre-compression. The firm attachment takes place only on the surface of the typical mattress materials.

To this aim we employ two ways that we apply either in an alternate fashion, depending on the mattress material or by employing both ways, so as to achieve the strong support of the spring cores on the mattress materials.

In the one way we make use of warm adhesive, which we apply onto the spring core spiral (6) that has been slightly heated up either through direct surface coverage or through immersion in warm adhesive. Thus, a large quantity of adhesive is economized, because the spiral of the spring core only holds up as much quantity as needed. The retention strength of the adhered spring core surpasses the 15 kg level per spring core, for spring cores having a 5,5 cm diameter and a 0.18 cm wire thickness. Thus for example, for the surface of a large innerspring mattress unit with dimensions of 180 cm x 200 cm to which approximately correspond 800 spring cores, the force necessary to detach the two mattress surfaces that the spring cores hold up, reaches the 800 x 15 = 12.000 kg. In this way, the flexible materials do not get detached from their positions.

This method solves in a perfect way a large problem faced by all mattress makers.

In the second attachment way we employ metallic connector clips (7) through which the end turns of the spring cores are attached to the mattress material in tow or more points for each spring core.

The mechanisms that achieve the adherence with the metallic lips are similar to the known binding devices used to staple paper, fabric, wood, etc. The metallic clips are stapled from the outside towards the inside in such a manner as to attach the mattress material with the end turns of each core, in order to achieve attachment.

The clipping mechanisms can be as many in number as the spring cores of each row, being capable to attach the whole spring core row simultaneously. Each stapling mechanism needs a counter plate, which the metallic clips can contact in order to bend their two ends towards the inside and up so as to achieve the attachment. This counter plate is positioned between adjacent spring cores, can be a whole single piece for the upper and lower clipping of each pair of spring cores, being capable to be adjusted in height, depending on the spring core height. Its support is done at the entry area of the spring cores through the space opening that is left between spring cores.

Stapling is done in one or more positions of each spring core, depending on the retainment strength we would like to achieve.

The metallic clips (7), depending on their strength, can be used to attach also the end turns of two adjacent spring cores (6a) that do not have to contact one another.

Thus, we accomplish the interconnection of the independent spring cores through the fabric (Figure 5).

Until now the employed method is the one that sprays or applies adhesive over the whole surface of the mattress material and where the spring cores are positioned. The surface that a single spiral connector wire (6) of 2 mm wire thickness and 90 mm diameter covers is about 9 cm x 9 cm = 81 cm i. e. about 15 times larger than the surface area of the wire we seek to adhere.

This proves that it is pointless to utilize large quantities of adhesive to achieve coverage of such a surface and to do it simultaneously in such a depth, so as to surely cover the thin spiral of the spring core. For this reason, the method we employ is a new application and provides a very good solution to this problem.

We apply the adhesive on the small surface of the wire and not on the large mattress material surface, achieving thus 90% adhesive savings.

The objective of our invention is to be able also to impart to the produced mattresses via the pre-compression method we employ, the proper positive qualities.

The pre-compressed spring cores have two important advantages: The first is that, even if the spring cores loose some length from their height with time due to pre-compression, there is still tension stored so that the mattress does not have recesses, but rather it remains level.

The second important quality of pre-compressed spring cores is the following one.

As it is known, spring cores, for every 1 cm of contraction, increase their resistance analogously. If, for example, at the 1 cm for a specific type of spring core the contraction creates a resistance of 200 grams, at the 2 cm it creates a 400 gr resistance and at the 10 cm contraction it creates a 2,000 gr resistance. Therefore, it is increased by a enfold.

If the spring core has already been pre-compressed for each incremental centimeter of contraction, the resistance is not doubled, but rather it increases only in a small percentagewise fashion, contributing little to the overall resistance level, as compared to the initial pre-compression that accounts for the majority of the imparted resistance in the spring core.

The method that is currently used to pre-compress the spring cores is their total encapsulation into pockets made of fabric or non-woven that is costly and expensive.

Our method incorporates the pre-compression of the spring core by their reapproachment between them of the two surfaces (7a) of non-woven materials that have been adhered on the end turns of each spring core with a flexible connecting clip (9). First, in order to accomplish our first objective, which is the adherence of independent springs onto mattress materials that cover the spring cores, e. g. in the non- woven we need strong adherence of the two end turns (6) of each spring core onto the mattress material.

To achieve this, we slightly warm up the end turns of the spring cores, so that from one point of view the adhesive does not loose heat quickly before it penetrates the non- woven surface and from another point of view, a better adherence quality on the spring core surface is achieved.

If the spring core with which the warm adhesive comes into contact is cold, then the adhesive cools faster, before a strong bond is achieved.

The non-woven or other mattress material in such a case functions as the medium that holds up the spring cores. The upper and lower surfaces (3) of the non-woven materials that the unity of the innerspring mattress exhibit large resistance and cannot be sheared off by forces that act on the plane of their surface. Thus, the produced product holds well the shape of the mattress.

These surfaces onto which the spring cores are to be adhered, are selected from mattress-making materials such as non-woven, felt, coconut fibre, foam, cotton etc.

In this manner, we achieve the independent spring core structural suspension. To achieve the pre-compression of the spring cores, we employ the following method and mechanism: When the non-woven or other materials have been strongly adhered on the two end turns of the spring cores (6), the discs of material (7a) that are situated within each spiral end turn are getting compressed with a suitable mechanism in order for them to approach each other to the degree we would like to achieve the pre-compression.

At that position their center is penetrated by a sharp lengthwise needle through which a suitable flexible connector clip (9) of appropriate strength is carried. At its two ends it bears plastic hooked ends (8) that are bonded or attached at their middle parts to the two ends of the connector clip. When this connector clip penetrates the two discs of the adhered non-woven, the plastic or metallic hooks come to a 90° position with respect to the connector clip and encapsulate the spring core that remains in the pre-compression position.

The compression of the spring cores is accomplished with the utilization of multiple mechanisms.

The compression can be done in the same mattress and in a varying depth at selected points of the mattress. Thus, it is possible to produce mattresses with an anatomical shape, having varying rigidity.

Also, whenever we utilize spring cores with a different height, we can pre-compress all of them uniformly, creating thus zones with a varying degree of rigidity.

The pre-compression mechanism (20) picks up the mattress after the adherence stage (19) of the spring cores onto the mattress materials. It contains many mechanisms to compress the spring cores and to effect the penetration of the connecting fibres.

By the motion of the mattress through this mechanism, we attain the gradual compression and attachment of all the rows of the spring cores.

An additional important innovative feature in our invention is the following one: Until now, automatic mattress assembly machines make use of one or rarely two spring- forming coilers.

Herein, as many spring coilers (15) can be utilized as there are springs in each mattress row of course we can make use of more than three spring coilers to achieve a greater productivity level. In this manner, we can produce simultaneously the necessary spring cores for the materialization of this invention with different wire thickness, different pitch, different spring core diameter and different number of twist turns. Thus, the produced innerspring mattress units acquire zones with a selected degree of rigidity.

The spring coilers (15) can be autonomous but can also have common operations, eg.

They can have: - Common motion source.

- Common regulation of the spring core pitch.

- Common adjustment of the spring core diameter.

- Common setting to produce the number of turns for each spring core.

- Common source to cut the wire.

It is possible through for them to be equipped with a separate motion source that is activated on a per case basis in the above operations, eg. In the pitch adjustment, changing the common parameter for a particular spring coiler.

Thus, from each spring coiler it is possible to produce alternatively spring cores having different heights.

The spring cores that are taller than the rest, after their adherence onto the mattress materials impart a slight material elevation to the mattress structure or it is possible to have the opposite. As mentioned above, it is feasible during compression to stabilize the spring core height by either subtracting this height difference or by achieving the same compression level in all the spring cores.

The produce row of spring cores from the multitude of spring coiler machines is advanced in parallel to the work station (16), where the spring cores undergo thermal processing and are subsequently led through a cooling space (17).

Following that, they are picked up by a carrier that has the analogous number of grippers. Each gripper engulfs each spring core around the middle area, leaving free the end turns that are to be covered with adhesive. If the temperature of the end turns after the thermal processing is not yet suitable to accept the adhesive material, then all the spring cores are transported over two warm surfaces, one on top and one at the bottom where by contact they get appropriately warmed up.

Subsequently, the carrier leads the spring cores over a container (17) that has the warm adhesive and rotates them from the vertical orientation to the horizontal position, so that the flat side surfaces come to the vertical position.

From within the adhesive container two bars emerge in a revolution type motion that come into contact with the two flat sides of the spring cores, where they deposit the necessary adhesive quantity.

Subsequently the two bars recess again into the adhesive. The spring cores with the proper carrier motion com again to the vertical position.

Following that, the spring cores are transferred to another carrier that consists of a set of grippers, where each gripper can slide on a common carrier bar so as to receed or approach the neighboring grippers. This is achieved with the known mechanisms and thus the necessary distance density between spring cores of each row is accomplished.

In this manner, we achieve not only to have a regulated adjustment of the distances between the spring cores of each row, but also varying spring core density from row to row.

This was until now impossible with the orthogonal arrangement distribution and assembling method for spring cores.

Subsequently, another carrier picks up the spring cores and starts to move towards the assembly mechanism (19) to the upper and lower sheets of mattress materials. These sheets await at an angle so as to facilitate the entry of the spring cores that bear at their end turns the adhesive. Thus, they come into contact with the mattress materials.

Upon their first contact and while in motion, the mattress materials acquire motion and are adhered on their internal surfaces. The mattress materials are advanced by a measured length and are ready to accept a new row. The additional movement of the mattress materials is adjusted so as to create the necessary distance density between the rows.

Further, the spring cores are led underneath the mechanisms (20) that create the pre- compression of the spring cores of the row with a punctuation of the two discs (7) of the mattress materials that are contained within the two end turns of each spring core and thus achieve their maintenance in the compressed position through a flexible connector clip (9). Each row is pre-compressed to the appropriate depth.

Subsequently, the processed product is cut (21) to the desired length of mattress needed. It is feasible through not to cut it and to have it rolled packed by a packaging machine (22) prepared fro transportation.

The mattress materials for the upper and lower surface of the created mattress can be supplied in cylinders that continuously unravel or could be from pre-cut stock of suitable lengths.

The utilization of spring cores of varying diameters from the different spring coiler machines, the capacity of each spring coiler machine to produce spring cores of two different rigidity values by differentiating the pitch and the capacity to approach or receed the spring cores between them, provide the possibility for multiple degrees of rigidity.

The machine complex offers four different choices of rigidity regulation that can be applied simultaneously or by choice in each mattress. These are: 1. The utilization within the production rows of spring cores with varying diameter as compared to the neighboring rows.

2. The production in the same row of spring cores, having different pitch and subsequently different height.

3. The change of the positioning distance density from one spring core row to the next one, as there are put in place and are getting adhered onto the mattress material.

4. The creation of rows where the spring cores have different distances between them as compared to the previously positioned row.

Thus, with this invention mattresses can be produced with controllable rigidity in different areas of the mattress.

All these selection capabilities permit the construction of innerspring mattress units, where each one can differ from any other one, without affecting the overall productivity and so as to satisfy all the demands.

The described method and the production mechanism permit an estimate of the productivity by analogy which can lead to a 5 to 10 times increase over the productivity of single head spring coilers that until recently are being utilized.

ADVANTAGES OF THE METHOD With this invention the innerspring mattress units that are produced have the following properties: 1. The spring cores are independent, so that they can receed independently without affecting their adjacent ones when these are compresses, and aspect occurring in spirally wound together spring cores.

2. There is pre-compression in the spring cores that, as described previously, provides comfort to the mattress.

3. The utilization of four different ways and degrees of rigidity that are applied by choice at every desired point of the mattress.

4. Large productivity. The output production of spring cores from 25 or 30 simultaneously operating spring coilers provides a great push for productivity, so that the production level of 100 springs/min in current machines is increased to a 500-600 springs/min level.

5. It provides a solution to the problem of attaching the spring cores to the mattress materials. Thus, the mattress materials do not need to be supported at the sides.

DESCRIPTION OF THE OPERATION First, the production run is programmed as to the type of mattress that is to be produced and with which wire thicknesses. Through the computer interface the following variables are set : - Width of the mattress.

- Length of the mattress.

-Density of the spring cores of each row.

-Density of distances between row.

-Thickness of spring core wire.

In addition, the degree of pre-compression is input (0%-100%).

The majority of the types of mattresses are standardized and coded and for this reason only the appropriate code is provided and the number of mattresses that are to be produced for that type.

The spring coilers (15) commence simultaneously to produce the spring cores for the whole row. We choose to have the construction of the mattress done from the lengthwise side so as the majority of the spring coilers can be involved to produce the necessary spring cores.

Subsequently, the produced row of spring cores is advanced with grippers to the work station (16) where thermal processing of the spring cores takes place. After the thermal processing, the whole row is transported to an area, where the gradual cooling down of the spring cores is achieved. Following that, each advanced row is being picked up by a carrier mechanism that leads the spring cores over the container with the hot melt (17). Simultaneously it rotates then by 90°, so that the end turns come to a vertical position. In that position two bars emerge from the adhesive container and by rotation they contact the two end turns, where they deposit the appropriate adhesive quantity and they then retreat submerging into the adhesive.

The carrier subsequently rotates by 90° and advances the spring core row, bringing it to a vertical position. Following that, the spring cores are being picked up by another transport mechanism (18) that bears the respective pairs of grippers where each gripper engulfs a single spring core. The grippers have the capacity with one of the known mechanisms to approach or receed from one another by the desired length. Thus, the desired in-between spring cores distance density is achieved. After picking up the spring cores from the set positions they have at the adhesive container station, the above-mentioned carrier regulates the desired distance density and the spring cores are subsequently led through two cylinders (19) that unravel the mattress materials. These materials await at an angle, so that they can come into contact with the spring core row.

By their in-between contact, the same mattress materials are set in motion. With this advance, the adherence of the whole row is achieved. After the completion of this motion, the mattress materials are further unraveled by the desired length, coming to the position where they will accept the next row of spring cores. Thus, the density of distances between the rows in the produced mattress is adjusted.

With subsequent adhesions of spring core rows, the innerspring mattress unit is completed.

Subsequently, the innerspring mattress unit comes to a mechanism that will convert it to pre-compressed. Row by row is compressed to the desired depth and there the proper in number mechanisms (20) are activated that penetrate the two discs (7a) of non- woven or other mattress materials that are contained within the two end spring turns of each spring core.

After the installation of the connector (9) that has the two plastic hooks at its ends, the permanent attachment of the spring cores in the pre-compressed state is achieved.

The produced innerspring unit product is sectioned with a cutting mechanism (21) to the desired mattress dimensions. It is possible though to produce it as a continuous product without cutting it and this facilitates its roll packing (22) for its transport.