FR2842263A1 - Wire fastener, for inserting into metal mesh forming sealing collar for oven door, has diamond-shaped head connected to two horizontal loops and helical screw - Google Patents

Abstract

The wire fastener which can be inserted into a metal mesh forming a sealing collar for an oven door is twisted to form a diamond-shaped head (26) which is inserted into an aperture in the door. This is connected to two horizontal loops (21, 22) and a helical screw (27). This can be screwed into the metal mesh. An independent claim is included for a sealing collar for an oven door comprising a tubular sleeve of metal mesh which is fastened together using fasteners as described above and then covered by braiding.

Description

IMPLANTABLE STAPLES BY SCREWING INTO A STRUCTURE

  MESHES IN PARTICULAR FOR OVEN JOINTS AND METHOD OF MAKING

  MANUFACTURE OF AN OVEN JOINT EQUIPPED WITH SUCH STAPLES

  The present invention relates to an element formed by bending a section of wire, said element being intended to serve as a means of fixing a mesh support, such as a wire mesh used in particular in the manufacture of a gasket for baking oven. This metallic element which will be designated by the term staple in the present

  text can also be referred to as clip or clip attachment.

  The present invention also relates to a method of manufacturing a seal for a baking oven using

a plurality of staples.

  Baking oven door trim and seals generally include a tubular wire mesh over which is woven a textile lining of high temperature resistant material. To secure and hold in position such a seal on the frame of the oven door, it is known to use a fixing clip or a staple made by bending a metal wire whose head has a configuration deformable, suitable for clipping into a

  recess in the oven door.

  In document US.5.341.601, the staple is located both in the textile lining and in the wire mesh. For this, the clip has two tapered ends which penetrate vertically through the two aforementioned layers, from the outside to the inside, over a certain length and which is then folded back so that the tapered end again enters the two aforementioned layers, from the inside to the outside. In document WO.98 / 40631, the clip has a structure which is substantially equivalent to that of document US.5.341.601 with the exception that the two tapered ends are in a plane perpendicular to that of the head of the clip. Their penetration into the tubular element forming a seal is carried out so that each tapered end crosses twice the thickness of the tubular element over a short distance. The extreme portion of the tapered ends is then folded over

  the outside of the tubular element forming a seal.

  In document EP.916.898, the clip has a part having a diamond-shaped configuration, forming a fixing head, and two longitudinal extensions, the first having a hook shape intended to penetrate the thickness of the wire mesh and the second having one end in the form of a loop to come to bear on the visible face of the wire mesh. The textile lining is attached to the wire mesh while the clip is already positioned and already hung on it. It covers the two longitudinal extensions and leaves visible only the diamond-shaped part, that is to say the head of

fastening the clip.

  The clip of document EP.916.898 has advantages compared to that of the two documents US.5.341.601 and WO.98 / 40631 mentioned above. In these documents, the operator who handles the seal when it is mounted on the oven door risks catching the tapered ends of the clip which protrude from the surface of the seal and possibly injuring themselves. On the contrary in document EP.916.898, only the fastening head of the clip is apparent and this risk is therefore completely avoided. Furthermore in this last document the stability of the clip is ensured on the one hand by the hook which penetrates into the wire mesh and on the other hand and especially by the clamping of the two longitudinal extensions between the wire mesh and the textile lining . However, this clip is not entirely optimal. It itself has drawbacks. For example during the manufacture of the seal, the only hooking of the clip in the wire mesh by a hook is not completely satisfactory since the clip can be caused to pivot and not to be positioned correctly during the application of the textile upholstery or even to unhook. In addition, the end of the second loop-shaped extension risks piercing the textile lining and damaging the seal.

see the oven door.

  The object of the present invention is to provide a clip which

  overcomes the aforementioned drawbacks.

  It is a staple implantable in a mesh or openwork structure, in particular a wire mesh, for oven door gasket, which in a manner known by document EP.916.898 is formed from a rhombus , able to be clipped into a recess in the oven door and having at least one support extension. Typically, according to the invention, this clip has a spiral end portion so that it can be positioned on a mesh or perforated support, in particular a trellis

metallic, by screwing.

  Thus, according to the particular arrangement of the staple of the present invention, the implantation of the staple is carried out, during the manufacture of the joint, the spiral end part penetrating inside the mesh or perforated support which is functional of the screwing angle and at most until application of the support extension on the external surface thereof. There is therefore no risk of variation in the positioning of the clip when the textile lining is placed over the support extension. The spiral end part is preferably substantially in the plane of the support extension, below the latter, so that the presence of this spiral part does not create an unacceptable excess thickness.

when the joint is crushed.

  To facilitate the positioning of the clip, during the screwing operation, it is preferable that the end of the spiral part is folded back to form a positioning point. It is then enough to position the point in a space between the meshes or in a day of the support then to rotate on itself the staple so as to carry out the screwing and therefore the final fixing of the staple on the support, the spiral part

  penetrating into said space following the positioning tip.

  In an alternative embodiment, the clip comprises, as a support extension, two longitudinal extensions formed by two isosceles triangles whose vertices are substantially at the base of the deformable head. The triangular configuration of the lateral extensions gives better rigidity to the clip. In addition, the fact that there are two lateral extensions, symmetrical with respect to the base of the head, makes it possible to obtain very good stability of the clip between the trellis.

  metal and textile trim.

  In this embodiment, the section of metal wire forming the clip defines successively, from one end to the other: a) the first longitudinal extension in the horizontal plane, b) the second longitudinal extension in the horizontal plane, c ) the head in the vertical plane, d) the spiral part in the horizontal plane,

  e) the positioning tip in the vertical plane.

  Advantageously, the common top of the triangles forming the two longitudinal extensions and the positioning tip are substantially on the vertical axis of symmetry of the part in

rhombus, forming the head.

  In another alternative embodiment, the clip comprises, as a support extension, two longitudinal extensions, each having successively a first straight portion, an end portion forming substantially a semicircle, a second portion

  straight, parallel to the first torsion.

  Preferably the spacing between the first and the second rectilinear sections of each longitudinal extension is substantially equal to the outside diameter of the spiral part, this diameter possibly being constant. In this embodiment, the section of metal wire forming the clip successively defines, from one end to the other: a) the first longitudinal extension in the horizontal plane, b) the head in the vertical plane, c) the second longitudinal extension in the horizontal plane,

  d) the spiral part under the horizontal plane.

  The spiral part comprises from one to three turns, preferably of

  one and a half to two full turns.

  The present invention also relates to a method of manufacturing a baking oven joint which consists of unwinding a tubular wire mesh, to implant by screwing into the mesh a succession of staples having the structure as described above, the part spiral terminal of said staples having penetrated into the wire mesh and to cover by braiding the wire mesh and the

  extension of the staples of a textile upholstery.

  The present invention will be better understood on reading the

  description which will be given of a particular example of a staple

  implantable in a mesh support by screwing and its application in a joint for a baking oven, illustrated by the appended drawing in which: FIG. 1 is a schematic perspective view of a first example of a staple implantable by screwing, FIG. 2 is a schematic top view, in plan, of the clip of FIG. 1, FIG. 3 is a schematic side view of the clip of FIG. 1 at the time of its implantation in a wire mesh, FIG. 4 is a partial schematic view of the clip of Figure 3 implanted in the wire mesh, Figure 5 is a schematic view of a braiding template, suitable for the formation of the textile lining around the wire mesh in which are installed staples and Figures 6 and 7 are schematic perspective views (Figure 6) and from above (Figure 7) of a second example of staple implantable by screwing.

  The description which will be given below is related to the use

  a screwable clip as a clip for fixing a gasket seal for an oven door, said gasket being constituted by a tubular wire mesh 2 and by a textile gasket 3 made of a material resistant to high temperature and covering , by braiding, the trellis

tubular metal.

  The clip 1 is formed by bending a section of metal wire. It therefore has two free ends between which are obtained, by the folding operation, the various constituent parts of this clip, namely, in the example illustrated, a head 4, two longitudinal extensions 5, 6, a spiral part 7 and a positioning tip 8. The head 4 of the clip is the part which is intended to make, by clipping, the fixing of the seal in a recess made in the oven door. It generally has the diamond-shaped configuration which is illustrated in particular in FIGS. 1 and 3, with two opposite wings 4a, 4b on either side of the axis of symmetry DD of said diamond. The maximum spacing between the two branches 4a, 4b is substantially greater than the diameter of the recess in the oven door. It is therefore necessary that the head 4 is elastically deformable in width so that it can penetrate

  by force in this recess by bringing the two branches 4a, 4b.

  The blocking in position in the recess is obtained thanks to the forces exerted by the pressure of the uprights 4a and 4b against the walls of the recess. However, it is understood that this blocking is only temporary and that it suffices to exert traction in the opposite direction to remove the head 4 from the clip 1 from the recess. Head 4 can have any other

  form, fulfilling the function recalled above.

  The two longitudinal extensions 5, 6 have several functions.

  They serve in particular as stops during the screwing operation of the clip 1, by limiting the penetration of the spiral part 7 into the wire mesh 2, as will be explained below. They ensure a very high stability to the clip 1 in all the operations of handling it by the operator during the installation and removal of the seal. Indeed, they constitute a bearing surface between the metal mesh 2 and the textile lining 3 which distributes the force brought into play when the operator forcibly introduces the head 4 into the recess of the oven door and, similarly, when removing the seal. Finally they make it possible to guide the longitudinal placement, in the general direction of the joint, of the head 4 during the

manufacture of the seal.

  The spiral portion 7 allows the fastening of the clip 1 in the wire mesh 2 or more generally in the mesh or openwork support, by screwing, that is to say by a simple angular pivoting. This fixing greatly facilitates the manufacture of the joint since it makes it possible to carry out, in automatic, continuous or semi-continuous sequences, on the one hand the positioning of the clip on the wire mesh and on the other hand the covering of the wire mesh and partially of the clip with the textile trim. If the clip 1 was not fixed on the wire mesh 2, these two operations should necessarily be carried out simultaneously or else it would be necessary to use external means for holding the clip in position during the

  2 0 covering by the textile lining.

  The purpose of the positioning tip 8 is to facilitate the introduction of the spiral part 7 into a free space of the mesh or openwork structure in which the clip 1 is to be implanted. Once the positioning tip 8 is placed in this space, it suffices to rotate the clip 1 to obtain that all or part of the spiral part 7

  also enters this space, like a screwing operation.

  This total or partial penetration is perfectly controllable, being

  function of the angle of rotation which is subjected to the clip 1.

  In the first exemplary embodiment which is illustrated, there are two longitudinal extensions 5, 6, which are both triangular, symmetrical and opposite by their apex, which is

  substantially at the level of the axis DD of symmetry of the diamond-shaped head 4.

  The triangle configuration of the longitudinal extension gives it improved rigidity.

  It goes without saying that other embodiments could have been envisaged both as to the shape and as to the number of longitudinal extensions or more generally of support extensions, capable of increasing the contact between the clip 1 and the support 2 on which it is located and also preferably the contact between the clip i and the

  gasket covering said support and partially said clip.

  In the first example illustrated, the spiral portion 7 comprises substantially two and a half turns, its maximum longitudinal dimensions L2 is substantially half of the maximum longitudinal dimensions Li of the two longitudinal extensions 5, 6 and twice the maximum longitudinal dimensions L3 of head 4. These provisions are

  given for information only and not exhaustive.

  The arrangement of the various parts indicated above and constituting the staple is obtained by folding with the following succession, from a first free end of the wire section to the second free end: a) first triangular longitudinal extension in the horizontal plane, b) second triangular longitudinal extension in the horizontal plane, c) diamond-shaped staple head in the vertical plane, d) spiral part in the horizontal plane, under the two triangular longitudinal extensions,

  e) positioning tip in the vertical plane.

  It should be noted that in this configuration, the first free end of the section corresponds to the apex 20 of one of the two triangles forming a longitudinal extension 5, which apex 20 is surmounted by the head 4. There is therefore no risk during the manipulation of the joint by the operator of displacement of this free end and therefore of

  perforation of the textile lining and degradation of the seal.

  The other free end of the wire section ends the positioning tip 8, the length of which is as short as possible to avoid possible degradation of the seal, when the latter is compressed, on the face opposite to the clip 1. Preferably this length is

  order or slightly less than 0.5mm.

  The spiral part is preferably made in the horizontal plane, as are the longitudinal extensions. The representation which has been made of them in Figures 3 and 4 shows the spiral part developed over a certain thickness, for the sake of clarity. However, it is indeed possible that this spiral portion is not strictly carried out in the horizontal plane; this is not annoying insofar as it will find

  in any case, this configuration when the seal is crushed.

  The joint manufacturing process can be, thanks to the staple of the invention, carried out automatically according to the following steps. The tubular wire mesh, already made up elsewhere, is unwound from a spool and directed towards the staple implantation station. It should be noted that the wire mesh, when it is unrolled with a low tension, finds its initial tubular configuration. At the staple implantation station, a given staple 1 is removed by a gripping tool, which grabs the head 4 and moves the staple 1 towards the tubular lattice so that the positioning tip 8 penetrates into a free space of a determined column of meshes of the trellis then the tool rotates the clip 1 on itself by a determined angle while following the continuous movement of the trellis and maintaining a certain pressure of the clip against the trellis. This has the effect of making the spiral part 7 of the clip 1 penetrate into the interior of the mesh 2, possibly until the latter 2 comes into abutment against the longitudinal extensions 3 0 5,6. Once this angular pivoting is achieved, the clip can be released and the mesh continue to move towards the braiding station, without risk

  the clip does not come off the trellis.

  FIG. 5 shows the braiding station 9 with in particular a cone 10 for guiding the wires 11 intended to constitute the

  braid 12 serving as a textile lining 3 for the seal 13.

  The cone 10 has a notch 14 which allows the passage of

head 4 of clip 1.

  The cone 10, which is in fact a hollow truncated cone, is supplied in the lower part by the wire mesh 15 in which are located, according to

  the same row of stitches, a plurality of staples 1.

  The braider, not shown, animates the wires 11 with appropriate movements for the constitution of the interlacing which constitutes the braid 12 from a braiding zone 16. This braiding zone 16 must be located downstream of the cone 10 to avoid that head 4 of

  the clip is not trapped between the braid 12 and the wire mesh 15.

  Preferably, the braiding area is about 2 cm above the

cone top 10.

  During braiding, the longitudinal extensions 5, 6 are covered by the braid 12 and are therefore interposed between this braid 12 and

the wire mesh 15.

  It is the braiding speed which determines the production rate.

  The distance between two staples depends on their location on the joint, being smaller in the corner areas of the door; it is generally of the order of 3 to 10 cm. It is therefore entirely possible to implement an automaton for implanting staples with a cycle of the order of 3 to 5 seconds for implanting a determined staple. A second example of embodiment is illustrated in FIGS. 6 and 7. This second example differs from the first mainly by the particular configuration of the two longitudinal extensions, by the constant diameter of the spiral part, by the absence of a positioning tip terminating said part. spiral and by the folding mode of the

stretch of metal wire.

  As regards the support extension, the clip 20 in question comprises two longitudinal extensions 21, 22, together defining the support surface. Each longitudinal extension 21, 22 successively has a first straight portion 21a, 22a, an end portion forming substantially a semicircle 21b, 22b and a second straight portion 21c, 22c, which is parallel to the first straight portion 21a, 22a. Compared with the aforementioned first example, the longitudinal extensions of which were in the form of an isosceles triangle, the longitudinal extensions 21, 22 according to this second example delimit a greater bearing surface for the same external dimensions, dimensions which correspond to the spacing d between the two rectilinear portions 21a, 21c. In a specific embodiment, this

  spacing was of the order of 5mm.

  As is clear from an examination of FIG. 7, this spacing d is substantially equal or even slightly greater, than the outside diameter of the spiral part. It is therefore the spacing d which defines the maximum overall dimensions of the clip 20 in width, this overall dimensions being a function of the dimensions of the mesh structure or

  perforated in which the clip 20 is to be implanted.

  In this second example, the diameter of the spiral portion remains constant so that the free end 24 of said spiral portion 23, used for introduction into the mesh or openwork structure, is offset

  with respect to the vertical axis of symmetry of the spiral part 23.

  The arrangement of the various constituent parts of the clip 20 is obtained by folding with the following succession, from a first free end 25 of the wire section to the second free end 24, serving for the introduction of the spiral part 23 in the mesh or openwork structure: a) first longitudinal extension 21 in the horizontal plane, b) diamond-shaped head 26 in the vertical plane, c) second longitudinal extension 22 in the horizontal plane and d) spiral part in the horizontal plane , below the two

longitudinal extensions 21, 22.

  As shown more precisely in Figure 7, the diamond head 26 and the spiral portion 23 have substantially the same vertical axis S of symmetry. The passage of the second rectilinear portion 21 of the first longitudinal extension 21 to the head of the clip 26 requires a particular folding of the section of metal wire, with an internal bent recess 27. It is the same for the passage of the head 25 to the first

  portion 22a of the second longitudinal extension 22.

  In top view in FIG. 7, it can be seen that only the two upper parts 26b and 26c of the head 26 of the clip 20 are in the vertical plane passing through the axis of symmetry S, the lower parts 26a and

  26d being on either side of said vertical plane.

  It should be noted that the first free end 25 of the section of metal wire partially overlaps the spiral portion 23 so that this free end 25 is locked in position during recovery by the

  braid of the longitudinal extensions 21, 22.

Claims (10)

CLAIMS 1. Staple implantable in a mesh or openwork structure, in particular a wire mesh, for oven door gasket, formed from a metal wire, having a deformable head, in particular in the shape of a diamond, suitable for be clipped into a recess in the oven door and having at least one support extension, characterized in that it has a spiral end portion (7) so that it can be positioned on the mesh support or perforated by screwing.   2.Staple according to claim 1 characterized in that the spiral end portion is substantially in the plane of the extension support, below it.   3.Staple according to one of claims 1 or 2 characterized in that   the end of the spiral part (7) is folded back to form a point positioning (8).   4.Staple according to one of claims 1 to 3 characterized in that it   comprises, as a support extension, two longitudinal extensions (5, 6) formed by two isosceles triangles whose vertices   are substantially at the base of the deformable head.   5.Staple according to one of claims 3 or 4 characterized in that   the section of metal wire forming the clip successively defines, from one end to the other: a) the first longitudinal extension (5) in the horizontal plane, b) the second longitudinal extension (6) in the horizontal plane, c ) the head (4) in the vertical plane, d) the spiral part (7) in the horizontal plane,   e) the positioning tip (8) in the vertical plane.   6.Staple according to one of claims 4 or 5 characterized in that   the common vertex of the triangles forming the two longitudinal extensions (5,6) and the positioning tip (8) lie substantially on the vertical axis of symmetry (DD) of the part in rhombus, forming the head (4).   7.Staple (20) according to one of claims 1 or 2 characterized in that   that it comprises, as a support extension, two longitudinal extensions (21, 22), each having successively a first straight portion (21a, 22a), an end portion (21b, 22b) substantially forming a semicircle, a second portion   rectilinear (21c, 22c), parallel to the first portion.   8.Staple according to claim 7 characterized in that the spacing (d) between the first and the second straight sections (21a, 21c) of each longitudinal extension (21) is substantially equal to   outer diameter of the spiral portion (23).   9.Staple according to claim 8 characterized in that the part   spiral (23) has a diameter which remains constant.   1O.Staple according to one of claims 1, 7 to 9 characterized in   that the section of metal wire forming the clip defines successively from one end to the other: a) the first longitudinal extension (21) in the horizontal plane, b) the head (26) in the vertical plane, c ) the second longitudinal extension (22) in the horizontal plane,   d) the spiral part (23) below the horizontal plane.   11.Staple according to one of claims 1 to 10 characterized in that   the spiral part (7,23) comprises from one to three turns, preferably   from one and a half turns to two turns.   12. Process for manufacturing a baking oven seal consisting of unwinding a tubular wire mesh (15), to be implanted by screwing into the mesh (15) a succession of staples (1.20) according to one of the   claims i to 1i, the spiral end portion (7,24) of said   staples (1,20) having entered the wire mesh and covering the wire mesh (15) and the support extension by braiding   (5,6,21,22) staples of a textile lining (12).