Spring Mattress and Method for Assembling a Spring Mattress

The invention belongs to the field of spring suspension mattresses—as opposed to foam core mattresses—typically the family of mattresses resting on a frame.

The invention is suitable for all mattress dimensions, including large or very large dimensions—in terms of thickness, length and/or width—hence including high-end and luxury positioning mattresses.

The invention is also suitable for mattresses used with a relaxation bed base, i.e. mattresses with raisable head and feet. The frame may be a bed base, a slatted frame, a bed frame, or a boxspring bed base. The mattress may be reversible, i.e. have upper and lower faces that can both be used for sleeping, and that it is advisable to use e.g. one for the summer and the other for the winter. It may also be non-reversible, with two different faces, only one being recommended for sleeping.

The suspension springs may be composed of pocket springs assembled in a sheet, or of single springs forming a spring frame. The suspension may also consist of a superposition of spring assemblies of the same type or of different types, including a superposition of a stack of pocket springs and of a non-pocket sprung carcass.

Mattresses with such a spring suspension are known, in a ticking which is a thick fabric, arranged in the form of a rectangle on each of the faces and sewn on the four sides of each face, by means of a braid, with ticking flanks arranged on the four edges of the mattress. The interior of the ticking often encloses sheets of non-woven fabric, blocks of fairing foam, points or lines of glue, sometimes staples and sometimes a metal frame.

Within the framework of a sustainable approach, one seeks to eliminate from the composition of the mattresses, the foam, glue, metal frame, staples and the sheets of non-woven fabric.

Moreover, such an approach is likely to reduce supply and production costs.

It is thereby possible to propose an ecological mattress made almost exclusively of natural materials, apart from the springs, or coming from recovery or recycling sectors, which also reduces the carbon footprint.

One of the manufacturing and assembly constraints is to ensure the sizing, stability and the perfect geometry of the mattress. In terms of sizing measurement and control, the standards only tolerate a margin of error of 1 cm with regard to the length and the width of the mattress.

According to the known manufacturing and assembly methods, it is not easy to ensure such dimensioning, stability and geometry by assembling only the spring layer or carcass and the ticking, i.e. the thick fabric covering, whether by pocketing the layer in the ticking or by padding the layer and ticking assembly, once assembled.

The necessary flexibility and elasticity of the spring layer, more particularly the pocket springs, is substantial, in particular along the lengthwise direction of the mattress when the spring strips are assembled lengthwise. The layer is at risk of retracting or stretching with variable force, depending on the size and the number of assembled springs, when pressing from the edge or when pressing on the layer from above.

According to the most widespread solutions, the sizing, stability and the geometry are ensured by the installation of a steel frame attached to each of the faces of the layer or carcass, or by fairing with foam blocks, bordering the edges of the layer or of the carcass, and glued to a sheet of non-woven fabric on each side of the suspension.

For mattresses composed of sheets of large pocket springs, the framing alone may not suffice. The pressure exerted by the springs with variable force, depending on the height of the springs, twists the lateral band of the framing positioned lengthwise either outwards (extension) or inwards (retraction). In such case, it is necessary to compensate with the addition of a slight foam fairing to stabilize the layer once same is assembled. The invention proposes solutions to such difficulties.

The invention consists of a bedding mattress comprising a suspension with springs defining a sleeping plane and a ticking on each face and on the edges.

The mattress is remarkable because same further comprises a fabric closed around the suspension and maintaining said suspension in compression parallel to said sleeping plane, the ticking being placed outside the fabric. The fabric is defined by the resistant character thereof: the fabric stretches little, whether plastically or elastically, and keeps such a property over time despite regular and significant stresses.

Thereby, due to the use of the fabric, the suspension is maintained in compression to undergo the stresses imposed on a daily basis by the bodies of people sleeping on the mattress, and the dimension of the latter is constant over time. Thereby, the size of the fabric when it is closed guarantees the size of the mattress.

The invention further consists of a method for manufacturing or assembling a bedding mattress comprising the installation of a suspension with springs defining a sleeping plane and the installation of a ticking on each face of the suspension and on the edges of the suspension.

The method is remarkable because same further comprises the compression of said suspension parallel to said lying plane and the closing of a fabric mounted tightly around the suspension under compression.

Thereby, the fabric keeps the suspension springs in compression, and ensures the longevity of the mattress.

According to advantageous and optional features of the method,

For high-end mattresses, a known composition for a summer-winter double-sided mattress is the composition shown in. The method used for sizing and stability is the method of the foam fairing. The composition with framing is not suitable for mattresses used with an articulated relaxation frame wherein the frame would fold irremediably when the articulation system starts to work.

shows the composition of the mattress: the pocket springsform a layer on each of the faces of which sheet of non-woven fabricwas placed, with a weight of 50 g/m2, glued at the periphery over foam blocksforming the fairing, and folded over the flank thereof. The adhesiveis present on the face, at the periphery and extends on the flank.

On each of the faces, on the non-woven face, a thick sheet of foam is present forming a coating. However, the coatingis not mandatory. The function thereof is to give more comfort quality to the mattress. The coating is preferably made of foam but may be composed of any useful synthetic or natural material. It is glued on the periphery to the non-woven sheet. The adhesiveis present on the face at the periphery.

On each of the faces, on the outer face of the coating, there is a sheet of non-woven fabricof 15 g/m2. Same is glued at the periphery to the coating. The adhesiveis present on the face at the periphery.

The padding materials, fabrics, textiles or other, are inserted into two trays, which are closed by sewing and pressed against the suspension by cushions(each consisting of a thread passing through the assembly from side to side and a button placed on the surface that holds the pad tightly against the suspension). The cushions are placed e.g. over the entire surface, in rows and columns, according to a rectangular two-dimensional array. A button on one surface can be connected by a common thread to a button on the opposite surface, arranged in the same place on the second side. The threads pass between two springs or through a spring.

is a sectional view of the same mattress, certain parts being artificially removed to allow the parts same would have hidden, to be seen. In addition, the lateral stripprotecting the side of the mattress can be seen, attached by a braidto the edges of the pads.

Shown in, the new embodiment is a significant development. An envelope or cover for the layer of pocket spring is created. Same does not use non-woven fabric.

The composition of the envelope or cover and of the layer or carcass of springs is shown in, which is a sectional view.

The new spring suspension mattressis based on the creation of a cretonne cover, or another preferably natural material, with low elasticity and sufficient resistance to absorb without deformation over time, the movements of the spring layer, without being stretched. Cretonne is a fairly strong fabric, consisting of hemp, linen or cotton threads on a weave (the weave being the mode of interlacing of the threads) such as a fabric and the contexture (interlacing) of which is square. For example, a cretonne with a grammage of 140 g/m2 or a fabric with a grammage of between 120 and 160 g/m2 is chosen. A cotton cretonne is preferred, or even 100% cotton.

An assembly is used in a compression table, without framing, and without fairing, or else with a lightweight fairing. The assembly is carried out without gluing, with the exception of gluing the pocket springs together (in the case where the mattress suspension consists of a layer of pocket springs).

The order of assembly is the following.

Step 1. Parts of the cretonne fabric cover are sewn, by sewing the bottom part, which is a rectangular facewith the dimensions of the suspension face, to the lateral part, the strip forming the flank, and choosing adjusted dimensions to prepare a tight threading of the suspension into the cover. The strip is assembled continuously with a coverage of about 10 cm. Two of the four sides,and, are visible in the figure whereas two other sides at 90° are not visible in the figure. The sides are of the same material as the face and have the dimension of the flanks of the suspension. The seam is referenced by. The seam is carried out over the entire rectangular perimeter of the rectangular face.

Step 2. The blank of the cretonne cover is placed in the compression table.

Step 3. A coatingformed for one of the faces, e.g. the summer face, is placed in the blank of the cover in the table, preferably without gluing.

Step 4. Blocksof foam, or of fiber agglomerate, or assembly of cotton wool and cretonne are placed so as to form the sides of the suspension, preferably without gluing, in the blank of the cover, in the table. The dimensions of the cover were chosen knowing that the flanks will be present. The flanks form a perimeter belt, which in the case of foam is a fairing.

Step 5. The layer or carcass of springsis laid. The layer has to be completely flattened by pressure without there being too much resistance nor space between the layer and the foam blocksforming the flanks. The compression table, or “cadreuse”, compresses the suspension: the springs are compressed perpendicular to the axis thereof, and are thus ready to accommodate the weight of a person sleeping on the mattress.

Step 6. A coatingformed for the winter face without gluing is preferably placed over the layer or the carcass of springs and on the blocks.

Step 7. The upper part of the cretonne, which is a rectangular face cut to the right size, is placed on the winter face.

Step 8. The envelope (or cover) is closed by stapling on the periphery of the upper part. The staples are referenced by. The stapling is carried out over the entire rectangular perimeter of the rectangular face of cretonne, with the four sides of which only two are visible in the figure-same are referenced byand.

The closing is carried out tightly, and the suspension is thus kept compressed parallel to the plane of the sleeping surface, because the thickness of the mattress is less than the length and width thereof. The suspension can be taken out of the “cadreuse” (or compression table). Since the cover is closed along the lengthwise direction and along the widthwise direction of the mattress, the compression parallel to the plane of the sleeping surface is maintained in both dimensions.

If appropriate, a row of quilting pointsis fitted along the edges, in line with the blocks. The quilting point each consist of a thread passing through the assembly from side to side and a button placed on the surface which keeps the face of the cretonnetight against the blocks). A button on one surface can be connected by a common thread to a button on the opposite surface, placed in the same place on the second side. The thread runs through the foam. In order to reinforce stability, in the absence of gluing, it is preferable to carry out the quilting of the assembly of the cover and the layer springs, on the periphery, at the blocks.

shows the suspension in the cover thereof, in a three-quarter view, certain parts being artificially removed to allow the parts same would have hidden, to be seen.

The coatingis not mandatory. Same improves the stability of the assembly and has a comfort function.

Stapling on one of the faces of the cretonne envelope (herein the upper face, i.e. the winter face) is envisaged to ensure the stability of the assembly when sitting on the mattress, whether on the winter face or on the summer face. On the other hand, the mattress remains perfectly stable, the cretonne sewn on one of the faces (herein the lower face or the summer face) thereof. But it is also possible that there is no stapling.

The dimensions of the envelope determine with reliability and reproducibility the size of the mattress, according to the length of the cretonne fabric and the height of the peripheral cretonne strip. The size of the seams and of the stapling of the top and bottom perimeter of the cretonne cover ensures the sizing and the geometry of assembly of the cover and of the layer (or spring frame).

It is specified that the blocksinternal to the envelope can be made without foam.

The blocks of material placed around the circumference of the layer or the carcass of springs can then be composed of three layers, parallel to the flank of the suspension (and hence of the mattress): a layer of cretonne or cotton, a layer of cotton wool and a new layer of cretonne, in this order, and the three layers are pre-assembled by sewing. The strip of the assembly is in four parts-two lengths and two widths, with the four parts joining each other in the corners.

The effect of the strip is to eliminate an undesirable effect on the edges of the mattress, called a rollover effect, which occurs if the sheet of springs comes directly into contact with the bell-shaped cover. To reinforce the corners, in the absence of fairing foam, it is also proposed to insert connections in the corners to smooth the geometric appearance of the spring strips and fill the void related to the circular character of the corner spring. But it is also possible to put a set of three layers, cretonne, cotton wool, cretonne on the entire flank.