FR2636983A1 - Braiding with an insert made of plastic and elastically flexible material - Google Patents

Abstract

A braiding of the kind comprising an apron 2 ending in a hollow reed 3 in the form of a tube housing an insert 10 made of plastic material is characterised in that this material has an elastic flexibility modulus of between 2700 and 3100 MPa. The plastic is preferably chosen from the group consisting of polyacetal and polyarylate materials.

Description

 The profiles, called piping, are well known in upholstery, luggage and furniture.

 A piping allows the assembly of two parts of fabric or hide hiding and thus aligning the seams of junction of two or more assembled elements.

 A piping is an element comprising a rod extended by a bib. The rod can be hollow or solid, grained or smooth in order to best combine with the adjacent tissues or skins.

 When this rod is hollow. so that it has a good hold, it is frequently provided with an insert which can be made of plastic. like polyolefins or PVC.

 The use of such PVC or polyolefin inserts is of attractive economic results, but these inserts have little nervousness. Other inserts in the form of steel spring with contiguous turns have sufficient nervousness to have a tensioning effect on the fabrics or skins but are difficult to implement which entails an expensive cost price. Furthermore. these metal inserts are of considerable weight. are susceptible to corrosion and cause magnetic disturbance.

 In order to remedy the drawbacks succinctly set out above. the Applicant proposes a new piping of the kind comprising a flap ending in a hollow rod in the form of a tube housing a plastic insert characterized in that this material has a modulus of elastic flexibility of between 2,700 and 3,100 MPa.

 The present invention thus makes it possible to obtain inserts and thereby piping that is both nervous and light with a favorable economic balance and does not have the drawbacks of piping with a metallic insert.

 In another aspect of the invention, the plastic material is also extrudable for rapid and economical production.

The characteristics and advantages of the present invention will become apparent from the description which follows, by way of example with reference to the appended schematic drawings in which
- Figure 1 shows in axial section a schematic assembly of principle made by a piping and two pieces of fabric
- Figure 2 shows in perspective a piping with hollow rod housing an insert constituted by a solid rod. according to the present invention
- Figure 3 shows in perspective a piping with a hollow rod housing a tubular insert, according to the present invention
- Figure 4 shows in perspective a piping with hollow rod housing an insert having the shape of a plastic spring.

 In a known manner and as shown in Figure 1, a piping 1 comprises a strip or flap 2 which is extended on one of its sides by a hollow and flexible rod 3 of generally cylindrical shape of revolution. Two separate pieces of fabric or skin 4, 5 are assembled by sewing or gluing. each with the flap 2, after having been superimposed by its end zone 4a or 5a, respectively with one of the faces of the flap 2. This assembly makes the parts 4 and 5 respectively secured to the flap 2.

so between them. at least in the immediate vicinity of the rod 3. The latter masks by its size and with the cooperation of the fold zones 4b, 5b of the parts 4, 5, the zone of connection of the parts 4, 5 with the flap 2.

 Figure 2 shows a piping according to the invention or the rod 3 is lined with an insert 10 having the shape of a solid rod 11, cylindrical of revolution, flexible and flexible.

This rod is made of a plastic material selected to have the desired mechanical qualities of flexibility. Thus, the plastic has a flexibility modulus of between 2,700 and 3,100 MPa and is preferably chosen from the group consisting of polyacetal and polyarylate materials. The mechanical qualities of this insert 10 are transmitted to the rod 3 and flap 2 assembly, insofar as the latter are made of a flexible and deformable material so as to be able to adapt and follow the deformations of the rod 11 when the latter is folded.

 FIG. 3 shows a second embodiment of the invention in which the insert 20 is constituted by a tube 21 made of a plastic material having the same elastic flexibility module as above. Preferably, this material will be chosen from the same group as above. The tube shape allows the mechanical properties of this insert to be adjusted as desired by decreasing or increasing the thickness of the wall of the tube 21 until a solid rod similar to that 11 in FIG. 2 is obtained at the limit.

 Figure 4 shows a third embodiment of an insert according to the invention. The insert 30 is in the form of a helical spring 31 shaped in a plastic material having the same elastic flexibility module as above.

 The plastic material will preferably be chosen from the same group as above. This spring 31 has contiguous turns to increase its elastic flexibility.

Claims (7)

RVENDICATIONS  1. Piping (1) of the type comprising a flap (2) ending in a hollow rod in the form of a tube housing an insert (10, 20, 30) of plastic material, characterized in that this material has an elastic flexibility module between 2700 and 3100 Mpa.  2. Piping according to claim 1 characterized in that the plastic is extrudable.  3. Piping according to claim 1 or 2, characterized in that the plastic material is chosen from polyacetal and polyarylate materials.  4. Piping according to any one of claims 1 to '3, characterized in that the insert (10) is in the form of a solid rod (11).  5. Piping according to any one of claims 1 to 3, characterized in that the insert is in the form of a tube (21).  6. Piping according to any one of claims 1 to 3, characterized in that the insert is in the form of a reloidal spring (31).  7. Pas-sepoil according to claim 6, characterized in that the helical spring has contiguous turns.