FR2941645A1 - Band fabricating method for forming style extension line in cushion for seat of motor vehicle, has rolling band formed of foam support carrying sections of self-gripping elements on receiving roller - Google Patents

Abstract

The method involves casting polyurethane foam on a rolling carpet. Sections (651) carrying self-gripping elements in a front face are formed on the polyurethane foam during polymerization, where the sections are applied by periphery of wheels defining a section of a band (69). The band formed of a foam support (695) carrying the sections of the self-gripping elements is rolled on a receiving roller. Independent claims are also included for the following: (1) a band defining style extension line of a cushion for a seat of a motor vehicle (2) a method for fabricating a cushion.

Description

B9168 - 2585 1.EN 1 MAKING SELF-PROPELLED BANDS FOR MOTOR VEHICLE SEAT

Field of the Invention The present invention relates generally to motor vehicle seats and, more particularly, to the provision of a seat member lining. The invention is more particularly applicable to the production of hook and loop strips integrated in a padding of a seat element to form styling lines. DISCUSSION OF THE PRIOR ART Seat upholstery for a motor vehicle is generally in the form of a quilting coated with a cap. The padding is a block of foam, molded to the desired final shape for the seat element. This block is assembled to a frame of the seat and is covered with a textile cap (woven or not), skin or synthetic material. The flexibility of the cap allows it to adapt to the shape of the padding. Most often, lines or reminder lines of form are provided in the apparent face of the padding and are provided with self-gripping strips to hold the cap and make him marry the forms of padding.

The styling lines are obtained by grooves in the pouring pan of the face of B9168 - 2585 1.EN

2 padding, these grooves receiving self-gripping strips whose pins are directed to the tank side. The foam then poured on the bowl fixed the self-gripping strips at the bottom of the throats of the padding.

It is important that the foam does not fill the pins of the hook and loop strips. For this, the back of the Velcro strips is usually coated with a thin layer of foam, whose role is to ensure a seal in the grooves of the tank. In practice, the foam is flamed on the back of a roll of hook-and-loop material which is then cut into slabs to obtain narrow hook-and-loop strips. These strips are then cut to the desired lengths to be placed in the grooves present in the quilting forming casting. The current strips are poorly suited to producing curved return lines in the surface of the seat element. Indeed, to be able to bend a strip in its plane, it is usually led to incise on its edges to provide notches allowing it to deform. A disadvantage is that such longer side edge edges leave gaps in which the casting foam passes to drown the pins. The cap attached to the padding can no longer be gripped by the hook-and-loop strips in the corresponding sections. In addition, the ends of the bands are problematic. Either the strip is shorter than the groove of the mold and foam can then pass through the end of the groove, or the band is longer and the pins then overflow from the end of the groove creating gaps in which the foam can also be injected. The ends of the style return lines are therefore, in practice, not functional.

B9168 - 2585 1.EN Abstract It would be desirable to improve the sealing of the casting foam at the level of the hook and loop strips. It would also be desirable to have self-gripping strips that can be used interchangeably on rectilinear sections and on curved sections of style return lines. It would also be desirable that the curved positioning of such shape-return lines is not accompanied by a risk of the self-gripping spikes embedded in the casting foam. It would also be desirable to obtain functional ends for the style reminder lines. To achieve all or part of these objects, as well as others, there is provided a method of manufacturing a band provided on one side, self-gripping elements and intended to form a styling line reminder in a quilting for motor vehicle seat, comprising the following steps: casting a polyurethane foam on a carpet; applying, on the foam during polymerization and by their rear faces, sections bearing on the front face of the self-gripping elements, the sections being applied by the periphery of a wheel defining the section of the strip; and winding, once the polymerized foam, the resulting strip consists of a foam support carrying the sections of self-gripping elements on a receiving roller. According to one embodiment of the present invention, the foam is deposited on a polyethylene film from which it is separated after polymerization.

According to one embodiment of the present invention, the foam is cast on a conveyor belt. There is also provided a strip for defining a style reminder line of a padding for a motor vehicle seat, comprising a foam support carrying a 3 B9168 - 2585 1.EN

4 minus a section of self-gripping elements covering the support only partially. According to one embodiment of the present invention, the ends of the strip are devoid of self-gripping elements. According to one embodiment of the present invention, the strip comprises sections of short length relative to the length of the strip, separated from each other by zones devoid of hook-and-loop fasteners. According to one embodiment of the present invention, triangular zones are devoid of self-gripping elements. According to one embodiment of the present invention, the foam support defines longitudinal sealing lips. There is also provided a method for producing a padding for a motor vehicle seat, in which polyurethane foam is injected into a mold whose bowl defines the apparent face of the padding and comprises grooves for receiving webs. self-gripping elements. It is also provided a padding for a motor vehicle seat. BRIEF DESCRIPTION OF THE DRAWINGS These and other objects, features, and advantages will be set forth in detail in the following description of particular embodiments in a non-limitative manner with reference to the accompanying figures in which: FIG. schematic view of a seat for a motor vehicle; Figure 2 is a perspective view, partly in section, of a seat cushion; Figure 2A shows a detail of Figure 2; Figure 3 is a perspective view of an example of a casting vessel of a seat cushion; Figure 3A shows a detail of Figure 3; B9168 - 2585 1.EN

FIG. 4 diagrammatically represents an installation for making self-gripping strips according to one embodiment of the present invention; Figures 5A, 5B and 5C are top views of various embodiments of hook and loop strips; Figs. 6A, 6B and 6C are sectional views of three embodiments of a belt forming wheel of the plant of Fig. 4; Figs. 7A, 7B, and 7C are partial sectional views illustrating the mounting of strips, obtained by the embodiments of Figs. 6A, 6B, and 6C, in a casting mold; and Figure 8 is a schematic perspective view of an example of a deformed strip for a curved pattern.

The same elements have been designated with the same references in the various figures. Detailed Description For the sake of clarity, only the steps and elements useful for understanding the invention are shown and will be described. In particular, the realization of the other elements of the padding has not been detailed, the invention being compatible with the usual techniques for molding a seat element padding. In addition, we will refer to the qualifiers superior, inferior, external, internal, front, back, etc. according to the seat member in the normal use position, and will be called "apparent" the faces intended to receive the user. Figure 1 is a schematic side view of a seat 1 for a motor vehicle. Such a seat comprises a seat 11 on which is articulated a backrest 12, usually surmounted by a headrest 13. The seat 11, the backrest 12 and the headrest 13 each comprise a lining attached to its frame , usually metallic. The armature 14 of the seat 11 can be connected to the floor 15 of the vehicle by means of a B9168 - 2585 1.FR mechanism.

6 slide. The seat 1 may also include one or more armrests (not shown). Figure 2 is a perspective view, partially in section, of a padding 2 of a seat for a motor vehicle. The padding defines a central portion (medallion) 21 framed by two lateral ribbings 22 and 23 generally thicker than the medallion 21, a front rim 24, also generally thicker, and a rear portion 25, most often hidden from the bottom of the backrest (12, figure 1) once the seat is assembled. Style recall lines are defined by grooves 26 of the apparent face of the padding at the bottom of which are embedded the self-gripping strips 3 (Figure 2A). These lines are generally present at the interfaces between the different parts 21, 22, 23, 24 and 25. The self-gripping strips 3 are intended to hook the underside of the cap (not shown) reported later on the padding to form the complete liner. FIG. 3 is a perspective view of a casting vessel 52 of an injection mold for obtaining the padding of FIG. 2. FIG. 3A is a sectional view illustrating a detail of the tank 52 at level of a style reminder line. The bottom of the tank 52 defines the upper form of the padding. To better bring out the bottom of the tank 52, its walls have been represented only by their edges. The style return lines are defined by sections 54 provided with grooves 542 (FIG. 3A) into which hook and loop strips 3 are inserted, the pins of the strips being directed towards the tank side 52. The objective is to fix the hook-and-loop strips in the foam of the padding by their back side without drowning the self-gripping elements or pins of these bands. According to the desired style reminders, the strips 3 are rectilinear or curved. The profiles 54 are formed so that the bottom of the grooves 542 are overhanging from the bottom of the B9168-2585 1.FR

7 zones 521, 522, 523, 524 and 525 of respectively definition of the inset medallion 21, the lateral embroiderings 22 and 23, the front rim 24 and the rear zone 25. This overhang allows the bands 3 to be found, in padding, at the bottom of grooves 26 (Figure 2). In practice, the profiles 54 are fixed to the bottom of the tank 52. To improve the sealing of the casting foam, the edges 544 and 546 of the profile 54 define a groove 542 of trapezoidal section and enlarged base. Thus, when the operator positions the band 3 in the groove 542, it is stuck by the shape of this groove. With a conventional band, if it is too short relative to the groove of the section 54, foam passes through the ends of the grooves. If it is too long, the pins protrude from the end of the section 54, thus removing the rear face of the band of the tank, which causes an interval through which the foam can pass and drown the tips of the ends. According to the embodiments described, a new technique for producing strips of self-gripping elements avoids these drawbacks. In particular, this technique makes it possible to create strips consisting of a foam support carrying sections of strips of self-gripping elements. The areas without pins allow either to solve the end problems of the profiles, or to create compressible areas to follow curved paths. FIG. 4 is a schematic side view of an embodiment of a foam tape manufacturing plant carrying sections of self-gripping elements. In this installation, the self-gripping elements are in the form of a band 61 of a width corresponding to the desired final width (width of the grooves of the profiles 54), carried by a roll 41. In the usual manner, the band 61 is formed of a synthetic film on one side the self-gripping pins. The roller 41 carries the band with the pins on the outside. The tape 61 is unwound B9168 - 2585 1.EN

8 of the roller 41 to a wheel 40 of application of its rear face on a cast foam 62. The objective is to apply sections 651 of self-gripping elements on the foam 62 during polymerization.

The application wheel 40 defines, by its periphery, the final shape of strips 6 for the profiles 54 and different sections will be illustrated later in connection with Figures 6A to 6C. Foam 62 comes from a mixing head 43 of foam forming chemical compounds. Typically, an isocyanate contained in a reservoir 44 is mixed with a formulated polyol contained in a reservoir 45. The chemical composition of the foam conditions its polymerization time and other characteristics. The foam 62 is deposited on a polyethylene film 63 unwound from a roll 47 on a conveyor belt 46 between at least two rollers 461 and 462. The film 63 serves as a temporary support for the strips produced. On the other side of the head 43 (at the output of the wheel 40), the fabricated strip comprises a foam support carrying hook-and-loop sections. This strip 6 is wound on a roll 48 while the polyethylene film 63 is separated from its rear face and recovered by a roller 49. Different intermediate guide rollers 42 are generally provided in the installation. In the example shown, the roller 41 directly contains sections 651 of good length regularly spaced according to the desired final destination. In another example, a cutting tool (not shown) dissociates the sections on their arrival on the wheel 40 so that they are spaced on the foam 62.

According to a particular embodiment, the flow of foam 62 continuously on the carpet 46 is carried out at a rate of a few grams per second (for example of the order of 1 to 10 grams per second). The application time of the band 61 on the foam during polymerization takes place between 10 to 30 seconds after casting. This time depends on the formulation B9168 - 2585 1.EN

This is the chemical time of the foam, and in particular its yarn time, which is defined as the time after casting when the foam makes a yarn if it is immersed in it and removes a wedge from a rectangular test piece. The speed of the installation is such that the separation on the roller 42 is effected, for example, between 40 to 60 seconds after casting, when the foam is sufficiently polymerized to be able to be wound on the roller 48. An installation of the type of that illustrated in Figure 4 may be provided to make one or more rollers 48 simultaneously. In the latter case, several wheels 40 respecting the profiles to be given to the foam strips are mounted in parallel on the same axis. We then find the same arrangement at the level of the other rollers. Only the polyethylene film 63 is, where appropriate, of great width and can temporarily wear several strips spaced apart from each other. FIGS. 5A, 5B and 5C show three examples of hook-and-loop strips on a foam support that can be produced by means of an installation as illustrated in FIG. 4.

The example of FIG. 5A is a strip 64 in which a self-gripping section 641 is supposed to cover the entirety of a rectilinear section 54. With respect to the usual strips, a difference is that the ends 642 of the strip 64 are devoid of pimples. Thus, the length of the section 641 is slightly less than the length of the profile 54, while the total length of the strip 64 is greater than the length of the profile. This allows, during assembly, that the entire section 641 is in the profile, which does not interfere with the injection of foam. In addition, the ends 642 form somehow end sealing lips for the band 64. The strip sections are, during the unwinding of the roller 48, cut in the gaps 642 between two sections 641. Such a mode of embodiment is more particularly adapted to the case where the length of the grooves 542 is known.

B9168 - 2585 1.EN

FIG. 5B illustrates another example of strip 65, in which several self-gripping sections 651 of relatively short length (of the order of a few centimeters for example) with respect to the lengths of profiles 54 (generally several tens of centimeters) are distributed over a foam support. The intervals 653 between two sections 651 may be of variable length, as well as the length of the sections 651. As in the previous embodiment, end sections 652 devoid of hook and loop elements are provided. The band 65 of FIG. 5B can not only be used in rectilinear profiles, but also in curved sections, taking advantage of the possible deformation of the intermediate zones 653 without pins. Where appropriate, the sections 651 are small enough that the individualization of the bands is effected at the level of the zones 653 (the zones 652 and 653 being undifferentiated) without it being necessary to know the length of the sections 54. 5C is a top view of still another example of strip 66 in which the gaps 663 between spiked areas 661 have triangular shapes on either side. This makes it possible to use a continuous hook and loop section (the sections 661 being connected to each other at their center in the width of the strip), while allowing placement in a curved section. Again, the ends 662 of the strips are free of pins. Figures 6A, 6B and 6C are sectional views along the line A-A 'of Figure 4, illustrating three wheel section embodiments 401, 402 and 403 and the strips then made. FIGS. 7A, 7B and 7C illustrate the placement of the strips 67, 68 and 69 obtained by the wheels 401, 402 and 403 in a profile 54 of a tank 52. In the example of FIG. 6A, the wheel 401 comprises 35 a groove 404 of rectangular section so as to give the B9168 - 2585 1.EN

11 band 67 a 675 foam support of rectangular section. As illustrated in FIG. 7A, the band 67 is set up like a conventional band (FIG. 3A). The difference is, in addition to the thickness of the foam 675, the fact that at least the ends (not visible in the sectional views) of the strips are devoid of pins. Figure 6B illustrates another example of a wheel 402 in which the foam support 685 has a wider base (in the orientation of Figure 6B). This allows that in position in the section 54 (Figure 7B), this base 686 covers by its edges the ends 544 and 546 of the section 54, which improves the seal. FIG. 6C illustrates yet another example of a wheel 403, in which a core of rectangular section 695 of the foam support is framed by two grooves 697 having shapes that are opposite to the ends 544 and 546 of the section 54. 6B, this amounts to providing a wider base 696 intended to protrude from the section 54 by engaging in the ends 544 and 546. As illustrated in FIG. 7C, this allows these ends 544 and 546 to be surrounded. of the profile 54 during the injection of the casting foam, which further improves the seal. The carpet 46 of the tape manufacturing facility is associated with rails 462 (FIG. 6C) for defining the edges of the foam support.

In the three examples above, the strip may be semi-continuous (FIG. 5A), discontinuous (FIG. 5B), semicontinuous notched (FIG. 5C), etc. FIG. 8 is a perspective view of a strip section 69 of the type of that illustrated in FIGS. 6C and 7C with sections of the type of those of FIG. 5B, in which sections 651 of pin elements are distributed over the foam core 695. The intervals 652 between the sections 651 allow the foam to undergo deformations 80 to absorb curved paths.

B9168 - 2585 1.EN

The installation of FIG. 4 can be adapted to successively produce rolls of strips of different size depending on the styling lines to which these strips are intended. According to one variant, several rollers are manufactured in parallel, each roll being intended for a different return line. According to yet another example, the length of the strips manufactured is variable on the same roll so that it successively carries the strips for the lines of reminders of a lining.

An advantage of the present invention is that it makes it possible to produce strips of self-gripping elements that do not pose a sealing problem in profiles to achieve styling reminders in a quilting. In particular, the invention makes it possible to solve the end problems of the profiles. Another advantage is that it allows the production of strips compatible with curved profiles without damaging the sealing in such traces. Another advantage is that the invention is compatible with existing tanks and profiles casting quilting. Various embodiments with various variants have been described. It will be appreciated that those skilled in the art may combine various elements of these various embodiments and variants without demonstrating inventive step. In particular, the choice of press and polymerization times depends on the nature of the foam used and is within the reach of the home of the trade. In addition, the distribution of spiked sections depends on the destination of the belts and may vary according to the types of profiles and ranges of seats.

Claims (10)

REVENDICATIONS1. A method of manufacturing a strip (6, 64, 65, 66, 67, 68, 69) provided on one side with self-gripping elements and intended to form a styling line in a padding (2) for a seat motor vehicle, characterized in that it comprises the following steps: pouring a polyurethane foam (62) on a carpet (46); applying, on the foam during polymerization and by their rear faces, sections (641, 651, 661) carrying, on the front face, hook-and-loop fasteners, the sections being applied by the periphery of a wheel (40, 401, 402, 403) defining the section of the strip; and winding, once the polymerized foam, the resulting strip consisting of a foam carrier (675, 685, 695) carrying the hook-and-loop sections on a receiving roll (48). 2. The method of claim 1, wherein the foam (62) is deposited on a polyethylene film (63) from which it is separated after polymerization. 20 3. The method of claim 1 or 2, wherein the foam (62) is cast on a conveyor belt (46). 4. Strip (6, 64, 65, 66, 67, 68, 69) for defining a styling line of a quilting (2) for a motor vehicle seat, characterized in that it comprises a support foam (675, 685, 695) carrying at least one section (641, 651, 661) of self-gripping elements covering the support only partially. Strip (64, 65, 66) according to claim 4, the ends (642, 652, 662) of which do not have self-gripping elements. 6. Tape (65) according to claim 4 or 5, comprising sections (651) of short length relative to the length of the strip, separated from each other by zones (653) devoid of self-gripping elements.B9168 - 2585 1.EN 14 7. Strip (66) according to claim 4 or 5, wherein triangular areas (663) are devoid of self-gripping elements. The strip (68, 69) according to any one of claims 4 to 7, wherein the foam support (685, 695) defines longitudinal sealing lips. 9. A method of producing a padding (2) for a motor vehicle seat, wherein polyurethane foam is injected into a mold whose bowl (52) defines the apparent face of the padding and comprises grooves (542 ) of bands of self-gripping elements, the strips of self-gripping elements being in accordance with any one of claims 4 to 8. 10. padding for motor vehicle seat 15 comprising at least one strip according to any one of claims 4 to 8.