Patent Description:
As is known, the perimeter strips are typically used to ensure uniform support for the peripheral portions of the mattress.

In other words, the perimeter portions are used to improve the structure of the mattress and to prevent local sagging and distortion caused by wear and tear.

As is also known, the perimeter strip may also be provided with a plurality of handles configured to facilitate flipping and rotating the mattress in order to ensure uniform wear over time.

These gripping handles are typically made according to one of two different methods.

In a first method, a web of fabric is sewn without interruption in such a way as to make a plurality of handles without taking into account the spacing between them or whether they are centred in relation to the perimetric band. This method is, for example, described and illustrated in document <CIT>, where a perimetric band is made in such a way as to provide it with a plurality of handles made one after the other by respective seams transverse to the longitudinal direction of extension of the perimeter band.

Using this method, it follows that when the mattress is covered, there will be a risk of having to close the perimeter band by joining the leading end with the trailing end at the centre of a pocket, thus adversely affecting its symmetricity and aesthetic appearance.

Moreover, according to this method, where the length of the pocket to be made is a parameter, the number of pockets is given by the perimeter of the mattress divided by the length of the pocket, without any possibility of changing it.

In another method, discrete portions of fabric are sewn onto the perimeter strip at predetermined intervals and positions so as to form handles by which to hold the mattress.

This method, however, has the disadvantage of being highly time consuming.

To overcome this drawback, document <CIT> describes a further method of making a perimeter band in which a ribbon strip is sewn onto a support taking advantage of the longitudinal stitch lines of the quilting process and the handles are formed of unstitched strip portions along the length of the strip.

Although this method fully overcomes the drawbacks of applying discrete handles to the support, it also has one all but negligible drawback, which is the possibility that the ribbon strip will tear when used since there is no reinforcement stitching transverse to the length of the strip.

In this context, the technical purpose which forms the basis of this invention is to propose a method and a machine for making a strip with handles designed for the perimeter covering of a mattress to overcome at least some of the above-mentioned disadvantages of the prior art.

More specifically, the aim of this invention is to provide a machine for making a strip with handles designed for the perimeter covering of a mattress, capable of optimizing operations in terms of time and reliability.

A further aim of this invention is to provide a machine for making a strip with handles designed for the perimeter covering of a mattress, that is at once aesthetically pleasing, highly versatile and robust. The technical purpose and aims specified are substantially achieved by a method for making a strip with handles designed for the perimeter covering of a mattress as described in the independent claim <NUM>.

Further features and advantages of this invention are more apparent in the exemplary, non-limiting description below, with reference to a preferred, but non-exclusive embodiment of a method and a machine for making a strip with handles designed for the perimeter covering of a mattress.

With reference to the accompanying drawings, the reference numeral <NUM> denotes in its entirety a method for making a strip F with handles designed for the perimeter covering of a mattress M.

The method <NUM> comprises a step a of providing a first continuous web N1 of fabric.

The first web N1 is substantially ribbon shaped. In other words, the first web N1 has a longitudinal dimension and a transverse dimension that are much greater than the thickness of the web N1. More specifically, the transverse dimension of the first web N1 substantially corresponds to the thickness of the mattress.

In a preferred embodiment, the method <NUM> may comprise a step a' in which a plurality of raw materials are assembled and sewn to obtain the first web N1 of fabric.

In this description, the term "raw materials" is used to mean a plurality of ribbon-shaped webs of fabric, which are assembled to form the above-mentioned first web N1, as well as the sewing thread and/or the adhesives used for assembling them.

The method <NUM> also comprises a step b of providing a second continuous web N2 of fabric.

Preferably, the second web N2 has a transverse dimension that is smaller than the transverse dimension of the first web N1. More specifically, the transverse dimension of the second web N2 is such as to make the web substantially suitable to be gripped by a user.

The method <NUM> then comprises a step c in which the second web N2 of fabric is superposed on the first web N1 of fabric along a main feed direction L of the webs N1, N2. The feed direction L of the webs N1, N2 is substantially parallel to their longitudinal dimension.

The method <NUM> comprises a step d of sewing the second web N2 onto the first web N1 in the main feed direction of the webs N1, N2.

In a preferred embodiment, there is a step of sewing an accessory element to a portion of the first web N1 along the feed direction L of the webs N1, N2, in particular, this accessory element being in the form of a hinge.

The step of sewing the accessory element is carried out during the above-mentioned step a' of assembling the raw materials.

The method <NUM> then comprises a step e of defining a production configuration for making gripping portions P on the strip F with handles at least as a function of the perimeter dimensions of the mattress M to be covered.

In this description, the expression "perimeter dimensions of the mattress" is used to mean a length and a width of the mattress M to be covered. Furthermore, the step e comprises defining a production configuration based on the length of the gripping portion P to be made.

Preferably, the step e is automated, as will become clearer as this description continues.

In other words, the positions of the gripping portions P along the strip F with handles are determined automatically as a function of the production configuration for making the gripping portions P.

After completing the step e of selecting the production configuration, the method comprises a step f of making a plurality of gripping portions P as a function of a production configuration by sewing the first web N1 and the second web N2 in such a way as to obtain the strip F with handles.

In other words, the first web N1 acts as load-bearing structure of the strip F with handles, while the second web N2, sewn onto the first web N1, is suitable for making the gripping portions P.

More specifically, the step f of making the gripping portions is accomplished by sewing the first web N1 and the second web N2 as the webs N1, N2 move along the main feed direction L.

The second web N2 is sewn onto the first web N1 by a sequence of stitches C parallel and transverse to the main feed direction L.

More specifically, in the method according to this invention, to make a gripping portion P as a function of the production configuration selected, the step of sewing the second web N2 to the first web N1 along the main feed direction L of the webs N1, N2 is interrupted and followed by a step of sewing the second web N2 of fabric onto the first web N1 of fabric along a direction transverse to the main feed direction L of the webs N1, N2, after which the step of sewing the second web N2 to the first web N1 along the main feed direction L of the webs N1, N2 is resumed.

The step of sewing the second web N2 of fabric onto the first web N1 of fabric along a direction transverse to the main feed direction L of the webs N1, N2 comprises making the transverse stitches in at least two distinct zones of the second web N2 spaced from each other along the main feed direction L of the webs N1, N2 so as to obtain a respective gripping portion P of the strip F with handles between the transverse stitch zones.

It should be borne in mind that during the step of sewing the second web N2 of fabric onto the first web N1 of fabric along a direction transverse to the main feed direction L, sewing the second web N2 of fabric to the first web N1 of fabric along the main feed direction L is interrupted.

The gripping portions P are each defined by the transverse stitch zones C disposed at a first and a second end of each gripping portion P, respectively. Preferably, as illustrated by way of non-limiting example in <FIG>, there may be one or more additional transverse stitch zones C1 so as to reinforce the connection between the first web N1 and the second web N2 in proximity to the gripping portions P.

Preferably, the method <NUM> may comprise a step of printing one or more images, logos, alphanumeric characters and/or special characters on the second web N2 as a function of the operating parameters.

As illustrated in <FIG>, this step is preferably performed by printing one or more images, logos, alphanumeric characters and/or special characters on the second web N2 in proximity to the gripping portions P.

Preferably, this step may be performed concurrently with the step c of providing the second web N2.

Preferably, the method <NUM> may comprise a step of cutting the strip F with handles as a function of the operating parameters, specifically the selected length of the strip F with handles and/or the perimeter dimensions of the mattress M to be covered.

This invention also has for an object a sewing machine <NUM> for making a strip F with handles designed for the perimeter covering of a mattress M, and which implements the method <NUM>.

The machine <NUM> is illustrated by way of non-limiting example in <FIG>.

The machine comprises a fixed frame <NUM> designed to support a sliding plane for feeding ribbon-like material along the main feed direction L.

Preferably, the sliding plane is configured for feeding the first and second webs N1, N2 of fabric. For this purpose, the frame is provided with means for moving and retaining the first and second webs N1, N2 of fabric along the above-mentioned feed direction L.

The machine <NUM> also comprises a first module <NUM> for feeding the first continuous web "N1" of fabric on the sliding plane along the feed direction "L". In a preferred embodiment, the first feed module <NUM> is suitable, in the method <NUM>, for carrying out the step a of providing a first continuous web N1 of fabric.

Preferably, the first feed module <NUM> may also comprise an assembly unit 102b and/or a sewing unit 102a for the first web N1 starting from a plurality of raw materials.

In a preferred embodiment, the assembly and sewing unit 102a is suitable for carrying out the step a' of the method <NUM>.

More specifically, the assembly unit 102b may comprise a sewing machine configured to make the first web N1 from a plurality of raw materials. Preferably, this sewing machine is a multi-needle sewing machine.

The sewing unit 102a may also comprise at least one additional sewing machine configured to make further, straight, wavy or zig-zag stitches on the first web N1 so as to reinforce the first web N1 and/or create patterns of a substantially aesthetic nature.

Preferably, the additional sewing machine is constrained to a respective guide which makes it movable relative to the feed direction L.

Preferably, the additional sewing machine is movable in a direction substantially transverse to the feed direction L.

Furthermore, the sewing unit 102a preferably comprises two additional sewing machines.

The machine <NUM> also comprises a second feed module <NUM> for feeding the second continuous web N2 of fabric on the sliding plane along the feed direction L in such a way that the second web N2 of fabric is superposed over the first web N1 of fabric. In a preferred embodiment, the second feed module <NUM> is suitable, in the method <NUM>, for carrying out the step b of providing a second continuous web N2 of fabric.

More specifically, the second feed module <NUM> is operatively positioned parallel with the first feed module <NUM> along the feed direction L. Preferably, but not necessarily, the machine <NUM> comprises a printing module <NUM>, operatively disposed downstream of the second feed module <NUM> and configured to print images, logos, alphanumeric characters and/or special characters on the second web N2 at the above-mentioned gripping portions P. In a preferred embodiment, the printing module <NUM> is suitable, in the method <NUM>, for performing the step of printing images, logos, alphanumeric characters and/or special characters on the second web N2 as a function of the operating parameters.

In an embodiment, the printing module <NUM> may be integrated in the second feed module <NUM>.

The machine <NUM> comprises a stitching module <NUM>, positioned downstream of the first and second feed modules <NUM>, <NUM> along the feed direction L, configured to sew the second web N2 on the first web N1, while also forming a plurality of gripping portions P using the first and the second web N1, N2 in such a way as to obtain the strip F with handles. In a preferred embodiment, the stitching module <NUM> is suitable for performing the step f of making a plurality of gripping portions P as a function of a respective production configuration by sewing the first web N1 and the second web N2 in such a way as to obtain the strip F with handles.

At structural level, the stitching module <NUM> preferably comprises at least two stitching units which are movably constrained to the frame <NUM> in such a way as to perform at least one controlled translation along a direction transverse to the main feed direction L.

Preferably, the two stitching units are spaced from each other by a quantity equal to the length of the handle P.

At functional level, the stitching performed by the stitching module <NUM> changes direction at the gripping portion P to be made. More specifically, the stitching is longitudinal and parallel to the feed direction L in the portions of the strip F with handles, where the second web N2 is sewn to the first web N1. Also, the stitching is transverse to the feed direction L in proximity to the gripping portions P, so as to define portions where the second web N2 is not sewn to the first web N1 to define the gripping portions P themselves.

In other words, the stitching module makes the stitching C transverse to the main feed direction L to define the gripping portions P.

It should be borne in mind that the stitching module <NUM> for sewing the second web N2 to the first web N1 does not interfere with the accessory elements, if any, such as the hinge, already assembled to the first web N1. As described in more detail below, the change in the direction of sewing the second web N2 to the first web N1 from the direction parallel to the main feed direction L to the direction transverse to the main feed direction L of the webs (and vice versa) is controlled by a control unit U.

According to an aspect of this invention, the machine <NUM> comprises a control unit U configured to send control signals to the stitching module <NUM> to make a specific strip F with handles.

The control unit is configured to control the sewing of the second web N2 to the first web N1 along the feed direction L of the webs N1, N2 and to control the sewing along a direction transverse to the main feed direction of the webs N1, N2 while interrupting the sewing of the second web N2 to the first web N1 along the feed direction L of the webs N1, N2.

In other words, the control unit U is configured for commanding the change of direction of sewing the second web N2 to the first web N1 from the direction parallel to the main feed direction L of the webs N1, N2 to the direction transverse to the main feed direction L of the webs N1, N2, and vice versa.

According to the present invention, the machine <NUM> also comprises a user interface unit I configured for entering at least the perimeter dimensions of the mattress M to be covered.

A calculator unit C is configured for defining the number and positions of the gripping portions P at least based on the perimeter dimensions of the mattress M to be covered and the longitudinal dimension of the gripping portion P.

The control unit U commands the change of direction of sewing the second web N2 to the first web N1 based on the positions and number of the gripping portions P as determined by the calculator unit.

According to another aspect, the machine <NUM> may comprise a cutting module <NUM> configured to cut the first web N1 and the second web N2 as a function of the selected value of the predetermined operating parameters selected. More specifically, the cutting module <NUM> may be configured to work automatically as a function of the predetermined operating parameters selected.

The invention achieves the preset aims and overcomes the drawbacks of the prior art.

In effect, a machine according to this invention are capable of optimizing operations in terms of time and reliability. In effect, thanks to the automated step of defining the production configuration, hence the positions of the gripping portions along the strip with handles, it is possible to increase the overall speed of the operations and to make them extremely precise.

Claim 1:
A sewing machine (<NUM>) for making a strip (F) with handles open seats designed for the perimeter covering of a mattress (M), comprising:
- a fixed frame (<NUM>) designed to support a sliding plane for feeding ribbon-like material along a feed direction (L);
- a first module (<NUM>) for feeding said first continuous web (N1) of fabric on said sliding plane along said feed direction (L);
- a second module (<NUM>) for feeding said second continuous web (N2) of fabric on said sliding plane along said feed direction (L) in such a way that said second web (N2) of fabric is superposed over said first web (N1) of fabric; said second feed module (<NUM>) being operatively positioned parallel with said first feed module (<NUM>) along said feed direction (L);
- a stitching module (<NUM>), positioned downstream of said first and second feed modules (<NUM>, <NUM>) along said feed direction (L), configured to sew said second web (N2) on said first web (N1), while also forming a plurality of gripping portions (P) using said first and said second web (N1, N2) in such a way as to obtain said strip (F) with handles open seats;- a control unit (U) configured for implementing a method according to one or more of the preceding claims, in such a way as to send control signals to said stitching module (<NUM>) for making gripping portions (P) of a strip (F) with handles open seats;
characterised in that it comprises
- a user interface unit (I) configured for entering at least the perimeter dimensions of the mattress (M) to be covered;
- a calculator unit (C) is configured for defining the number and positions of the gripping portions (P) at least based on the perimeter dimensions of the mattress (M) to be covered and the longitudinal dimension of the gripping portion (P);
the control unit (U) is configured for commanding the change of direction of sewing the second web (N2) to the first web (N1) from the direction parallel to the main feed direction (L) of the webs (N1, N2) to the direction transverse to the main feed direction (L) of the webs (N1, N2), and vice versa;
the control unit (U) commands the change of direction of sewing the second web (N2) to the first web (N1) based on the positions and number of the gripping portions (P) as determined by the calculator unit (C).