WO2007046211A1

WO2007046211A1 - Fastener strip for a moulded foam seat bun

Info

Publication number: WO2007046211A1
Application number: PCT/JP2006/318679
Authority: WO
Inventors: Mineto Terada
Original assignee: Ykk Corporation
Priority date: 2005-10-21
Filing date: 2006-09-14
Publication date: 2007-04-26
Also published as: GB0521492D0

Abstract

A fastener strip (103) to be moulded into a foam seat bun (141) comprises a cover portion (105) and a fastener portion (107). The fastener portion (107) comprises hooks (111) for attaching a seat cover to the formed foam seat bun (141). The cover portion (105) comprises resiliently flexible arms (115) which hold the fastener portion (107) in place and which grip a pedestal (101) of a mould. When the foam seat bun (141) is moulded, the fastener strip (103) is attached to the pedestal (101) by pushing the arms (115) over the top of the pedestal (101) to hold the fastener strip (103) in place during moulding and to form a seal between the cover portion (105) and the pedestal (101) to prevent liquid foam material fouling the hooks (111) of the fastener portion (107).

Description

DESCRIPTION

Fastener Strip for a Moulded Foam Seat Bun Technical Field

This invention relates to a fastener strip for a moulded foam seat bun. In particular it relates to a hook and loop-type fastener strip for a moulded foam seat bun, a foam seat bun incorporating a hook and loop-type fastener strip therein and a mould for forming a moulded foam seat bun having a fastener strip incorporated therein.

Background Art

Moulds for forming foam seat buns comprising a hook and loop-type fastener strip are well known. Such fastener strips are used to securely retain a portion of a seat cover bearing a co-operating hook and loop-type fastener (typically loop material) within a groove in the foam seat bun. To incorporate the fastener strip into the foam seat bun, the strip is placed on an inner surface of the mould and liquid foam material is injected into the cavity of the mould. The liquid foam material expands and solidifies to incorporate the fastener strip therein.

In general, such moulds and fastener strips should satisfy two specific requirements of the moulding process.

Firstly, the fastener strip should be held securely in place while the liquid foam material is injected into the cavity of the mould. When the liquid foam mateπal is injected into the cavity of the mould, it exerts a force on the fastener strip and the mechanical relationship between the fastener strip and the surface of the mould should prevent the fastener strip from shifting during injection of the liquid foam material. To this end various methods of attaching the fastener strip to the surface of the mould have been described.

Secondly, when the fastener strip is seated on the surface of the mould, a seal should be formed between the fastener strip and the surface of the mould so that liquid foam material is prevented from reaching the face of the fastener strip which is in contact with the surface of the mould, thereby avoiding fouling of the hooks (or loops) on the fastener strip by seepage of the liquid foam material thereon.

US 5005242 and US 5101539 descπbe a clip for holding a hook and loop fastener on the surface of a mould. The clip holds the hook and loop fastener in place while preventing liquid foam material from engulfing the elements of the hook and loop-type fastener.

US 5171395 and US 5259905 describe a pedestal for a mould and a cooperating fastener strip. The fastener strip has pre-formed foam walls running along its longitudinal edges. The foam walls enable positioning of the fastener strip on the top of the pedestal, with the pedestal located between the foam walls. The foam walls prevent seepage of liquid foam material onto the elements of the fastener strip.

It is also known to incorporate magnetic material into the fastener strip and a corresponding portion of the wall of the mould. EP 1358826 describes a fastener strip having two flange-like sealing legs having a relatively flat bottom surface. Magnetically attractive particles are incorporated in the sealing legs to hold the fastener strip securely to the surface of a portion of the mould containing magnetic material and to seal the sides of the fastener strip against the wall of the mould during moulding of a foam seat bun.

EP 1452106 describes a fastener strip having magnetic particles dispersed in individual discontinuous areas thereof. The fastener strip has a substrate and hook elements formed on a surface of the substrate to which a seat cover can be attached.

It is clear that any mechanism which is employed to attach the fastener strip to the wall of a mould should also allow separation of the fastener strip from the wall of the mould after the foam seat bun has been moulded. Using magnetic parts in the fastener strip addresses this need while providing a seal between the fastener strip and the wall of the mould and maintaining the fastener strip in place during moulding. However, using such magnetic parts makes these fastener strips expensive and difficult to recycle. Also, use of such magnetic strips is inefficient, as they are only required during moulding of the seat bun and are not needed thereafter.

JP 06-091662 describes a mould having an elongate recess for receiving a fastener strip. The side walls of the recess are sloped such that the recess widens from its mouth to its base. This results in the corners of the mouth having a sharp edge.

The recess is suitable for holding a fastener strip having a hook and loop-type fastener mounted on a compressible backing material. The fastener strip is partially inserted into the recess by pushing the face bearing the hook and loop type fastener elements beyond the mouth of the recess. The fastener strip is held in place by the gripping action of the edges of the mouth of the recess on the compressible backing mateπal of the fastener stnp

A disadvantage of this mould is that it only suitable for a fastener stnp comprising hook and loop-type fastener elements mounted on a compressible backing material, which is complex and costly to produce A further disadvantage is that the sharp edge of the mouth of the recess may damage the fastener stnp when it is inserted into and removed from the recess

US 6439537 descnbes a seat bun mould with a recess to receive a fastener strip to be moulded into a seat bun The recess has an end wall shaped so as to provide a snap-fit with the end of the fastener stnp, in order to prevent fouling of the fastener stnp during moulding of the foam seat bun The end wall has a generally concave shape in cross section and has a bevelled opening to facilitate insertion of the fastener stnp into the recess The end of the fastener stnp is inserted into the recess by placing the fastener stnp over the recess and by pushing the fastener stnp into the recess

A disadvantage of this anangement and of the arrangement of JP 06-091662 is that as the fastener strip sits within the wall of the recess, the face and part of both of the edges of the fastener stnp are contained within the recess and when the liquid foam matenal is injected into the mould only the rear face of the fastener stnp is in contact with the foam It is preferable if the two edges of the fastener stnp are also m contact with the foam, to improve the bond between the fastener stnp and the foam

A further disadvantage of these arrangements is that the recess must be wider than the fastener stnp When forming a foam seat bun, the fastener stnp is commonly located at the bottom of a groove in the bun, so that the cooperating loop matenal on the seat cover can be inserted within the groove to form a smooth surface on the finished seat bun It is preferable that the width of the groove is as small as possible, so that the presence of the groove cannot be felt in the finished seat bun In the arrangements of US 6439537 and JP 06-091662, if the recess is at the top of a pedestal in the wall of the mould, then the resulting groove produced by the pedestal will be relatively large, in order for the groove to accommodate the fastener stnp

It is an object of this invention to provide a hook and loop type fastener that can be incorporated securely at the bottom of a nanow groove formed m a foam seat bun and a mould for forming a moulded foam seat bun having a fastener strip incorporated therein

Disclosure of Invention One aspect of the present invention provides a fastener strip to form part of a moulded foam seat bun, the fastener strip comprising: a fastener portion for attachment of a cover to the seat bun; and a clip portion for removably mounting the fastener strip in a mould prior to moulding the foam seat bun.

The fastener portion and the cover portion may be formed separately or may be formed as one piece.

The fastener strip cooperates with a pedestal in a mould to form a moulded object to which the fastener strip is to be attached, a portion of the pedestal being receivable within the fastener strip.

Preferred features and advantages of the invention will be apparent from the following description and the accompanying claims.

The invention will be further described by way of examples with reference to the accompanying drawings in which:

Brief Description of Drawings

Figure 1 is a perspective view a prior art fastener strip having magnetic particles in a projection running along a central portion of the strip;

Figure 2 is a partial sectional view of a prior art fastener strip, similar to that shown in Figure 1 ;

Figure 3 is a cross sectional view taken along a line HI-ITI of Figure 2;

Figure 4 is a cross sectional view of a fastener strip and pedestal according to a first embodiment of the invention;

Figure 5 is a cross sectional view of a fastener strip and pedestal according to a second embodiment of the invention;

Figure 6 is a cross sectional view of a fastener strip and pedestal according to a third embodiment of the invention;

Figure 7 is a perspective view of a foam seat bun comprising fastener strips according to the invention;

Figure 8 is a perspective view of the cover portion of Figures 4 and 5; and

Figure 9 is a perspective view of the pedestal of Figures 5 and 6. Best Mode for Carrying out the Invention

Figure 1 is a perspective view of a prior art fastener strip 1 having magnetic particles in a projection running along a central portion of the strip, as described in EP 1452106. The fastener strip 1 has a substantially flat substrate 3 and engaging elements 5, in the form of hooks 5, directed upwards from the substrate 3. Projections 7 project from the substrate 3 along a central portion of the substrate 3. The projections 7 are made of the same synthetic resin as the substrate 3, and have magnetic particles mixed within the resin. Magnetic particles are not dispersed throughout the fastener strip 1, but are only located within the projections 7. Walls 9 project upwards from the substrate 3 along longitudinal edges 10 of the fastener strip 1. Each wall 9 is made up of a plurality of wall portions 11 arranged in two rows 13. The wall portions 1 1 of one row 13 overlap the spaces 15 between the wall portions 11 of the other row 13.

When the fastener strip 1 is to be incorporated into a foam seat bun, the fastener strip 1 is inverted and placed on the surface of the mould so that the hooks 5, walls 9 and projections 7 lay on the surface of the mould, and so that the substrate 3 faces the interior of the mould. The wall of the mould includes a magnetised material to which the magnetic particles in the projections 7 are attracted when the fastener strip 1 is placed on the surface of the mould. This attractive force between the wall of the mould and the projections 7 keeps the fastener strip 1 in place when the liquid foam material is injected into the mould during moulding of the foam seat bun. The top 17 of the walls 9 of the fastener strip 1 are at least as high as the projections 7 and hooks 5 so that when the fastener strip 1 is inverted and placed on the surface of the mould, the top 17 of the walls 9 is in contact with the surface of the mould. In this manner the walls 9 prevent passage of liquid foam material beyond the walls 9 to the hooks 5. The seal between the top 17 of walls 9 and the surface of the mould is enhanced by the attraction between the magnetic components in the wall of the mould and those in the projections 7. When the fastener strip 1 of Figure 1 is used in a mould to form part of a foam seat bun, the fastener strip 1 may be placed on a portion of the surface of the mould which is flush with adjacent parts of the wall, or it may be placed on an elevated portion of the wall of the mould, i.e., on a pedestal.

Figure 2 is a sectional view of a central portion of a fastener strip having a structure similar to that of the fastener strip 1 of Figure 1. The portion of the fastener strip 1' shown has a central projection 7 and two adjacent hooks 5. In this prior art fastener strip 1', the projections 7 do not contain magnetic particles dispersed throughout the projections 7, rather a magnetic wire material 19 is disposed within the projections 7.

Figure 3 shows a cross sectional view along the line Ill-Ill of Figure 2. It can be seen that the magnetic wire 19 passes between the projections 7 and is held in place by the projections 7. In other known prior art fastener strips a plurality of metal wires 19 are disposed across the width of the fastener strip and the upper surface 21 of the projections 7 is not flat but comprises hooks 5 like the hooks 5 on the rest of the substrate 3.

Figure 4 is an end view of a fastener strip and pedestal according to a first embodiment of the invention. The pedestal 101 is partially recessed in the wall of a mould 110 for moulding the foam seat bun, so that the pedestal 101 projects into the cavity of the mould 110. In other embodiments the pedestal 101 may sit on the surface of the mould. The fastener strip 103 is comprised of a cover portion 105 and a fastener portion 107. A perspective view of the cover portion 105 is shown in Figure 8. The fastener portion 107 is bonded to the cover portion 105 by the use of adhesive or is connected to the cover portion 105 by a mechanical or form-locking connection, as described below.

The fastener portion 107 has a structure similar to the fastener strip 1 of Figure 1, having a substrate 109 and fastener elements 111 projecting from the substrate 109. However, the side walls 9 and the central magnetic formations 7 are not required. In this embodiment the fastener elements 111 are hooks but in other embodiments the fastener elements may be any type of surface fastener such as loops or a mixture thereof to co-operate with a another surface fastener provided on the seat cover. The cover portion 105 is comprised of an elongate base 113 having two opposed arms 115 running along its length and extending therefrom. The arms 115 extend from edge portions 119 of the base 113 and bend in towards each other to form a C-shape with the portion of the base 113 therebetween. The two arms 115 are resiliency flexible and cooperate to form a clip portion, as described below.

The cover portion 105 is preferably made of a mateπal which bonds with the material of the foam seat bun. For example, if the foam seat bun is made of polyurethane (PU) then a suitable material for the cover portion is polybutylene terephthalate (PBT) or PU. The fastener portion 107 is made of a material which can easily be moulded to the desired shape having hooks 111 using conventional methods and is readily secured or adhered to the cover portion 105, such as polypropylene (PP).

The base 113 extends beyond the point of connection of the arms 115 to provide flanges 121 running along the length of the cover portion 105. These flanges 121 provide anchor portions for the fastener strip 103 when integrated with a foam seat bun. In other embodiments anchors are attached to the outer surface 123 of the base 113 to prevent the fastener strip 103 being separated from a moulded foam seat bun, as is known m the art. Such anchors are described, for example, in EP 1358826.

The pedestal 101 has a generally rectangular cross section. Towards the upper surface 125 of the pedestal 101 there are grooves 127 in the sidewalls 129 of the pedestal 101, to receive the ends 128 of the arms 115 of the cover portion 105 in a snap- ^' fit arrangement. The pedestal 101 can be coated with a suitable composition prior to moulding, to prevent the foam seat bun from adhering to the pedestal 101 following moulding.

In use, the fastener portion 107 is inserted into the cavity 131 of the cover portion 105 formed between the base 113 and the arms 115. The fastener portion 107 may inserted by sliding the fastener portion 107 into the end of the cover portion 105 or by pushing the fastener portion 107 through the opening in the cover portion 105 between the ends 128 of the arms 115. The fastener portion 107 can be bonded to the cover portion 105 using adhesive applied to the cover portion 105 and/or to the fastener portion 107 prior to insertion of the fastener portion 107 into the cover portion 105. Generally the [arts 105, 107 are relatively flexible to avoid discomfort when the seat is in use. However, in some applications the parts may be sufficiently rigid to enable the fastener portion 107 to can be held between the arms 115 of the cover portion 107 without adhesive.

Once the fastener strip 103 has been assembled in this manner, it is removably attached to the top 125 of the pedestal 101 by snapping on to the pedestal or by pushing the ends 128 of the arms 115 along the sidewalls 129 of the pedestal until they enter the grooves 127 in the sidewalls 129. The resiliency flexible arms 115 cooperate to form a clip portion so that the arms 115 sitting in the grooves 127 form a mechanical connection between the fastener strip 103 and the pedestal 101 which is sufficiently strong to hold the fastener strip 103 on the pedestal 101 during moulding of the foam seat bun, to resist the force exerted on the fastener strip 103 by the liquid foam material when it is injected into the cavity of the mould. Furthermore, the mechanical snap-fit connection between the fastener strip 103 and the pedestal 101 creates a seal between these parts 101, 103 to prevent seepage of liquid foam material beyond the arms 115, thereby preventing fouling of the hooks 111 of the fastener portion 107 of the fastener strip 103. End walls may be provided on the cover 105 to prevent ingress of the foam polymer material to the hooks. The end walls can be formed when a strip of cover 105 is cut to a desired length, using a heat cut or welder cut process. In another embodiment, transverse walls on the fastener portion 107 may be provided to prevent ingress of material. These may be moulded in situ or may be formed by a heat cut or weld cut process. In yet another embodiment, the fastener strip is located between end walls on the pedestal.

Once the foam seat bun has solidified, the formed foam seat bun is removed from the mould thereby detaching the fastener strip 103 from the pedestal 101.

In this embodiment the fastener strip 103 is made of two separate parts 105, 107. In an alternative embodiment the fastener strip 103 may be formed as a single part although suitable moulding materials which bond to the foam seat bun material during moulding tend to be more expensive.

Figure 5 shows a second embodiment of the invention. In this embodiment the shape of the pedestal 101' is different to that of the pedestal 101 of Figure 4. A perspective view of the pedestal 101 ' is shown in Figure 9. In particular, the corners 133 running along the longitudinal edges of the top wall 125 of the pedestal 101' are rounded to ease attachment of the fastener strip 103 to the pedestal 101'. A further difference between the two pedestals 101, 101 ' is that the cross sectional shape of the pedestal 101' of this embodiment is generally T-shaped, i.e. the wall portion below the grooves 127 of the pedestal 101 of Figure 4 has been removed. This avoids the possibility of grooves 127 from being clogged with liquid foam material during moulding of a foam seat bun and results in a relatively narrowly trench formed in the foam seat bun, which is advantageous as explained above.

In Figure 6, a further embodiment of invention is shown In this embodiment, the shape of the cover portion 105' is different to the shape of the cover portion 105 in the first embodiment of Figures 4 and 5. The ends 128' of the arms 115' are bulbous, having a generally round cross section. An advantage of arms 115' of this type is that the fastener strip 103' can be easily pushed over the top of the pedestal 101' as the bulbous ends 128' of the arms 115' ride over the curved corners 133 of the upper wall 125 of the pedestal 101'. A further difference between the cover portion 105' of Figure 6 and the cover portion 105 of Figures 4 and 5 is that on the inside of the arms 115' there is a shoulder 135 which holds the fastener portion 107 within the cover portion 105'.

Figure 7 shows a foam seat bun 141 having fastener strips 103, 103' according to the invention integrated therein. A fabric cover can attached to the foam seat bun 141 by means of loop portions attached to the inside surface of the cover or forming part of the ^' fabric cover, as is known in the art.

Various modifications will be apparent to those in the art and it is desired to include all such modifications as fall within the scope of the accompanying claims. For example, some of the outer rows of the fastener elements 111 may be omitted from the fastener strip portion 107 at the longitudinal edges as these are not likely to engage with the fastener elements on the seat cover or the like.

Industrial Applicability

From the detailed foregoing description, the reader will see that this invention provides a mould for forming a foam seat bun having a hook and loop type fastener incorporated securely therein at the bottom of a narrow groove.

Claims

CLAIMS:

1. A fastener strip to form part of a moulded foam seat bun, the fastener strip compπsing: a fastener portion for attachment of a cover to the seat bun; and a clip portion for removably mounting the fastener strip in a mould prior to moulding the foam seat bun.

2. A fastener strip as claimed in claim 1, wherein the clip portion comprises two opposed resiliently flexible arms.

3. A fastener strip as claimed in claim 2, wherein the clip portion is part of a cover portion which, during moulding, covers the fastener portion, the clip portion compπsing the two arms and a base, the arms projecting from the base and bending inwards towards each other to form a C-shape with a portion of the base therebetween.

4. A fastener strip as claimed in claim 3, wherein the fastener portion is disposed within a cavity formed by the base and the two arms.

5. A fastener strip as claimed in claim 3 or 4, wherein the cover portion further comprises anchor-portions.

6. A fastener strip as claimed in claim 5, wherein the anchor portions comprise flanges projecting from the base.

7. A fastener strip as claimed in any one of claims 1 to 6, wherein the ends of the arms are bulbous.

8. A fastener strip as claimed in claim 4, wherein the fastener portion is retained within the cavity formed by the base and the two arms by the two arms.

9. A fastener strip as claimed in claim 8, wherein each arm comprises a shoulder for retaining the fastener portion within the cover portion.

10. A fastener strip as claimed in any one of claims 1 to 9, wherein longitudinal edge regions of the fastener portion are devoid of fastener elements.

11. In combination, a fastener strip and a pedestal for a mould for forming a moulded object to which the fastener strip is to be attached, a portion of the pedestal being receivable within the fastener strip.

12. A combination as claimed in claim 11, wherein the pedestal comprises sidewalls having indents therein for receiving a portion of a fastener strip.

13. A combination as claimed in claim 11, wherein the pedestal is substantially T- shaped in cross section.

14. A combination as claimed in any one of claims 11 to 13, wherein the corners of the pedestal which are received in the fastener strip are rounded.

15. A combination claimed in any one of claims 11 to 14, wherein when the fastener strip is attached to the pedestal the fastener strip to form a seal with the portion of the pedestal received within the fastener strip.

16. A foam seat bun comprising a fastener strip as claimed in any one of claims 1 to 17.

17. A fastener strip to form part of a moulded article, the fastener strip comprising: a fastener portion; and a clip portion for removably mounting the fastener strip in a mould prior to moulding the article.

18. In combination, a fastener strip and a pedestal for a mould for forming a moulded object to which the fastener strip is to be attached, a portion of the pedestal being receivable within the fastener strip.