Patent Application
20250107632
The object of the invention is a pocket spring assembly having at least one stiffened edge of the assembly. The invention also relates to a mattress comprising such an assembly, as well as to a method of manufacturing of the pocket spring assembly.
The present invention belongs to the field of mattresses comprising a pocket spring assembly. Such pocket spring assemblies, also referred to in the industry as innersprings, are formed by a plurality of coil springs which are enclosed in pockets of textile material, each spring being placed in an individual pocket, the adjacent pockets forming pocket springs strings, also referred to as pocket springs webs, the said pocket springs webs being connected side to side to form a pocket spring assembly which can serve as a mattress layer in a mattress.
One of the important technical problems in the design of pocket spring assemblies is to ensure that the edges of such assemblies are stiffened. A number of solutions can be found in the state of the art, which are based on a suitable adjustment of the parameters of the spring elements at the edge of the assembly, e.g. through a suitable selection of the wire thickness or the number of spring coils or the hardness of the foam from which the blocks constituting the spring element in the assembly of pocket spring elements are made. One known solution is also to pack the springs more densely in the edge area of the mattress layer, as for example disclosed in publication DE 40 31 654 A1.
In another solution, the springs to form a stiffened border are placed in the intermediate space created between two springs of an adjacent row of pocket springs.
Still another approach is proposed in publication WO2018/224139A1, which discloses a method of manufacturing a pocket spring assembly having an edge with springs having different stiffness characteristics compared to the springs of the core of the assembly. The disclosed method comprises the step of providing a core (body) of the pocket spring assembly comprising a plurality of first webs (or strings) of pocket springs, followed by the step of attaching at least one second web of pocket springs to a lateral surface of said core of the pocket spring assembly, so that at least one second web of pocket springs extends (runs) in the longitudinal direction of the core of the pocket spring assembly. The springs of at least one second web of pocket springs have spring characteristics or spring geometry different from the springs in the first webs forming the core of the pocket spring assembly. At least one second pocket springs web, when connected, forms a pocket spring assembly together with the core. In order to stiffen the longitudinal edges of the assembly, the step of providing the aforementioned core additionally comprises terminating the core at both longitudinal ends with pocket spring webs in which springs with different spring characteristics or geometries are provided compared to the springs contained in the pockets of the first pocket spring webs, forming the core of the pocket spring assembly. This provides stability at the longitudinal ends of the assembly. In an advantageous embodiment of such a pocket spring assembly, the method also comprises attaching at least one second pocket spring web to both the first lateral surface and the second lateral surface of the core of the pocket spring assembly, which, in combination with the stiffening provided by said pocket spring strings provided at the longitudinal ends of the core, results in the pocket spring assembly thus formed having a stiffened periphery completely surrounding the core built of the first pocket spring webs. The longitudinal core ends or the longitudinal core edges are to be understood here in the context of the core-forming process, which takes place by attaching successive pocket springs webs side by side, parallel to each other. The first pocket springs web, to which the subsequent webs are subsequently attached, and the last one of the attached pocket springs webs provide the longitudinal core ends/longitudinal core edges, and the direction in which the core is built up by attaching the subsequent webs is referred to as the longitudinal direction.
Furthermore, in the method according to the invention described in WO2018/224139A1, providing the main core of the assembly comprises attaching a pair of non-woven layers to the upper and lower surfaces of the core of the pocket spring assembly so that the non-woven sheets cover said core and extend beyond the core transversely with respect to the longitudinal direction, ensuring that the attachment of at least one second web of pocket springs to the lateral surface of the core is carried out so that said at least one second web is placed between the pair of non-woven sheets. Furthermore, to achieve the attachment of the at least one web between the non-woven sheets, the method comprises holding the non-woven sheets by means of a clamping device and pushing said at least one second pocket springs web by means of a pusher between the non-woven sheets to the lateral surface of the core. The method also comprises compressing the springs of at least one second pocket springs web before attaching at least one second pocket spring to the core of the assembly, and allowing the compressed webs to relax when attached to the side surface of the core of the assembly. This step ensures that the second web adheres well to the non-woven sheets, as the adhesive is pressed against the upper and lower non-woven sheets due to the relaxation of the previously compressed springs.
The described solutions from the state of the art are quite complex in the context of manufacturing the described pocket spring assemblies. Furthermore, although the presented known solutions make it possible to ensure edge stability/stiffening, the implementation of the mentioned solutions in practice involves significant and costly modifications to already existing production lines, which are usually based on conventional spring assembly machines producing spring assemblies from continuous (so-called endless) pocket springs webs, in which all springs have the same or very similar elastic properties. The attachment of the stiffening spring webs to the longitudinal ends of the assembly can easily be done with the already mentioned conventional spring assembly machines, using technology that is well-known and has been used for years. To this end, one simply provides an additional source of stiffening spring web and ensures that it is attached in a manner analogous to the attachment of the first webs forming the core of the assembly. However, a complex technical problem is presented by providing a means of stiffening the assembly on the sides extending along the longitudinal direction of the core (i.e. in the direction of the attachment of the successive webs to form the core). The realization of such a method by attaching second stiffening web/second stiffening webs attached to the lateral plane of the core and running in its longitudinal direction requires the addition of a new step, necessitating the provision of additional equipment or significant modification of already existing machines in the production line.
The purpose of the present invention is therefore to provide a pocket spring assembly with a stiffened edge, suitable for use in the construction of a mattress, and which can be produced simply and cheaply and at the same time can provide better edge stability compared to solutions known from the state of the art.
This has been achieved by solutions according to the invention, as defined by independent claims. Advantageous embodiments of the invention are defined by the dependent claims.
The object of the invention is a pocket spring assembly comprising:
In an advantageous embodiment of the invention, at least one and preferably two third pocket springs webs are positioned at one of the longitudinal ends of the core of the pocket spring assembly, the springs in said third pocket springs webs having different stiffness characteristics than the springs of the first pocket springs webs.
In another advantageous embodiment of the invention, the invention, at least one and more advantageously two third pocket springs webs are positioned at both longitudinal core ends of the pocket spring assembly, the springs in said third pocket springs webs having different stiffness characteristics than the springs of the first pocket springs webs.
In yet another advantageous embodiment of the invention, a set of two second pocket springs webs is attached to the first lateral surface of the pocket spring core, whereby a first textile strip and a second textile strip are attached to said set of two second pocket springs webs and to the first and second layers of the textile sheet.
In another advantageous embodiment of the invention, the pocket spring assembly comprises at least one second pocket springs web and advantageously a set of two second pocket springs webs attached to the second lateral surface of the core of the pocket spring assembly, the assembly comprising an additional first textile strip and an additional second textile strip, which are attached to at least one second pocket springs web, and preferably to a set of two second pocket springs webs attached to the second lateral surface of the core of the pocket spring assembly and to the first and second layers of textile material, respectively.
Also an object of the invention is a mattress comprising a pocket spring assembly, which comprises:
In an advantageous embodiment of a mattress according to the invention, in the pocket spring assembly at least one, and more preferably two third pocket spring webs are positioned at one of the longitudinal core ends of the pocket spring assembly, the springs in said third pocket spring webs having different stiffness characteristics than the springs of the first pocket spring bands.
In another advantageous embodiment of a mattress according to the invention, in the pocket spring assembly at least one, and more preferably two third, pocket springs webs are positioned at both longitudinal core ends of the pocket spring assembly, the springs in the third pocket springs webs having different stiffness characteristics than the springs of the first pocket springs webs.
In yet another advantageous embodiment of a mattress according to the invention, in the pocket spring assembly a set of two second pocket springs webs is attached to the first lateral surface of the pocket spring core, whereby a first textile strip and a second textile strip are attached to said set of two second pocket springs webs and to the first and second layers of the textile sheet.
In another advantageous embodiment of a mattress according to the invention, the pocket spring assembly comprises at least one second pocket springs web, and advantageously a set of two second pocket springs webs, attached to a second lateral surface of the core of the pocket spring assembly, whereby the assembly comprises an additional first textile strip and an additional second textile strip, which are attached to at least one second pocket springs web and preferably to a set of two second pocket springs webs attached to the second lateral surface of the core of the pocket spring assembly and to the first and second textile layers, respectively.
Also an object of the invention is a method of manufacturing a pocket spring assembly comprising the steps:
wherein, according to the invention, the method is characterized in that it comprises the additional steps of:
d) attaching a first textile strip to the first textile layer along the longitudinal direction of the pocket springs core, so that a part of said first strip extends beyond the core of the pocket spring assembly,
In an advantageous example of the implementation of the method according to the invention, step a) provides a core of the pocket spring assembly with at least one and preferably two third pocket spring webs attached to the outermost pocket spring web at the longitudinal end of the core of the pocket spring assembly, the springs in the third pocket spring web having different stiffness characteristics than the springs in the first pocket spring webs.
In another advantageous example of the implementation of the method according to the invention in step (a), a pocket spring assembly core is provided with at least one and preferably two third pocket spring webs attached to the outermost pocket spring webs at both longitudinal ends of the core of the pocket spring assembly, the springs in the third pocket spring web having different stiffness characteristics than the springs in the first pocket spring webs.
In yet another advantageous example of the implementation of the method according to the invention, in step d) the two first strips of textile material are attached to the first layer of textile material along the longitudinal direction of the pocket spring core, so that two parts of said first two strips project beyond the pocket spring core on both opposite sides thereof, and in step e) at least one second pocket spring web, and preferably a set of two second pocket spring webs, is additionally connected to the second lateral surface of the core of the pocket spring assembly, while in step f) the attachment of the second textile strips to at least one second pocket spring web and preferably a set of two second pocket spring webs and to the second layer of textile material is carried out on both opposite sides of the core of the pocket spring assembly.
The terms used in this description are to be understood in the manner accepted in the technical field of the invention, including the description of the state of the art presented above and the state of the art documents cited, unless the description clearly indicates otherwise.
Within the meaning of the invention, the pocket spring assembly comprises a core of the assembly and at least one second pocket springs web connected to the lateral surface of the core and extending in the longitudinal direction of the core, the core of the assembly being formed by a plurality of first pocket springs webs containing springs having different stiffness characteristics from the springs contained in said at least one second pocket springs web connected to the lateral surface of the core. Thus, there are at least two types of webs in the pocket spring assembly: the first webs, containing springs with a first stiffness characteristic, which, connected side to side, form the core of the pocket spring assembly. The longitudinal direction of the core is to be understood as the direction in which the successive webs forming the core are attached to each other, the longitudinal ends of the core being the outermost first webs from which the core of the pocket spring assembly is formed. The core of the pocket spring assembly may also according to the invention comprise at least one and more preferably two third pocket springs webs, which are positioned at both longitudinal ends of the core of the pocket spring assembly and attached to the outermost first webs, the springs in the third pocket springs webs having different stiffness characteristics than the springs of the first pocket springs webs.
Put together in the design of the pocket spring assembly according to the invention, the coil springs in the first, second and third pocket spring webs differ in their stiffness characteristics and are thus able to provide an assembly with a stiffened edge. It is known to the expert in the field that the stiffness characteristics of the helical springs can be adjusted accordingly, for example by using different spring diameters. Within the meaning of the invention, a helical spring has upper and lower coils and a plurality of central coils between the upper and lower coils, the largest of the diameters of the central coils of the spring being taken as the diameter of the spring within the meaning of the invention. It is known to the expert in the field that by using the same wire thickness, it is possible to achieve different spring stiffness (hardness) by selecting the coil diameter accordingly. Thus, assuming springs are made from the same diameter wire and are of the same spring height, a smaller diameter spring will be harder (stiffer) than a larger diameter spring. In addition, the spring's stiffness is influenced by the number of coils and the wire thickness, with the spring's stiffness increasing as the thickness of the wire from which the spring is made increases, while decreasing the number of coils increases the hardness.
The stiffness of the spring is also influenced by its primary height, understood as the height of the spring before it is placed in the pocket. As the primary height of the spring increases, its stiffness increases. With the above in mind, an expert in the field will easily realize a selection of springs with different stiffness characteristics by adjusting accordingly the above-mentioned parameters of spring construction, in particular the wire diameter, the original height and the diameter and number of spring coils. All parameter combinations known to the expert in the field that ensure different stiffness characteristics of the springs arranged in the first, second and third webs of the pocket spring assembly according to the invention are within the scope of the invention.
A textile material in the sense of the invention includes any textile material providing ability to join webs to form a mattress layer. Examples of such materials are non-woven fabrics, felts, woven fabrics.
The object of the invention is illustrated in more detail in the following description and in the drawing wherein:
All references in the figures showing different embodiments of the invention refer to identical elements of the pocketed springs assembly.
As it is better illustrated in the exploded view of
As also shown in
Using
As also shown in
The solution according to the invention is an effective, simpler and cheaper alternative to reinforcing the edge of the pocket spring assembly compared to solutions known in the art. Attaching strips connecting at the same time the second pocket spring webs and the first and second layers of textile material not only provides effective reinforcement of the edge, but also significantly improves and stabilizes the shape of the corners, which become more filled and shapely. Depending on the configuration of the strips used and the geometry of the springs, the solution according to the invention allows for providing different comfort/stiffness zones in the middle and outer part of the mattress layer. Regardless of the above advantages, the production of the pocket spring assembly proposed by the invention can take place at reduced production costs compared to the production of the assemblies using known methods. In the embodiments shown in the drawing, a complete stiffening of the edge of the assembly is provided by ensuring that the second pocket spring webs are glued on both sides of the core, which is also equipped with stiffening resulting from placing third pocket spring webs on the longitudinal ends of the core. It is clear to the person skilled in the art, however, that the scope of the invention also includes solutions in which only partial stiffening of the edge is provided, for example by adding only one second pocket spring web without adding third webs. In the embodiment shown, adding second and third pocket spring webs in sets of two webs is arranged. It is clear to the person skilled in the art that stiffening of the edge, depending on the needs, can also be achieved by adding single second and third webs, or by adding sets comprising more than two second and third webs. Each such solution is covered by the content of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| PL446290 | Oct 2023 | PL | national |
