FR2575796A1 - MECHANICAL FIXING DEVICE FOR FIBROUS MATERIAL - Google Patents

Abstract

FIXING DEVICE INTENDED TO BE PLACED IN A FIBROUS MATERIAL, CHARACTERIZED IN THAT IT INCLUDES: -A FIRST CYLINDRICAL ELEMENT 10 INCLUDING A CENTRAL BODY 13 INCLUDED BETWEEN TWO ENDS 11 AND 12, ONE OF THESE TWO ENDS 11 HAVING A DIAMETER EXTERIOR 17 SUPERIOR THAN CENTRAL BODY 13; THE ELEMENT BEING CROSSED THROUGHOUT BY A BORE 14; A SECOND CYLINDRICAL ELEMENT 20 INCLUDING A CENTRAL BODY 19 INCLUDED BETWEEN TWO ENDS 21, 22 ONE OF THESE TWO ENDS 22 HAVING AN EXTERNAL DIAMETER 31 GREATER THAN THAT OF THE CENTRAL BODY; THESE CENTRAL BODY HAVING AN EXTERNAL DIAMETER CORRESPONDING TO THE INTERNAL DIAMETER OF THE BORE 14 OF THE FIRST ELEMENT 10 AND BEING CROSSED THROUGHOUT BY A BORE 23 EQUIPPED WITH A THREAD 24; - MEANS TO TIGHTEN THE ONE ON THE OTHER THE FIRST AND THE SECOND ELEMENT AFTER INTRODUCING THE SECOND IN THE FIRST.

Description

Mechanical fastening device for fibrous material This

  The invention relates to fasteners for use in fibrous material

  such as a composite material, and it concerns more

  In particular, a type of attachment device

  sertion for such matters.

  The present invention aims to satisfy a certain

  in industries currently using machines

  fibrous materials for panels and the like, instead of conventional metallic materials. Fibrous materials are

  normally constituted by a plurality of layers of

  individual fibers, held together by means of a binder.

  When it is necessary to attach an article to a fibrous structure by means of a bolt or similar fastening component, it is necessary to pierce an opening in the

material and tapping it.

  When an opening is created in fibrous material, the layers of fibers are necessarily disturbed and the individual fibers delimiting the opening break

  necessarily. This then leads to a reduction in the

  resistance of the material in the area surrounding the opening.

  It is difficult to tap a hole made in

  fibrous materials in the sense that satisfactory tapping can not often be achieved. In addition, by tapping, slice between the fiber layers and this further leads to a decrease in the resistance of the material in this area. Broken fibers also tend to tear off the mass of the material, resulting in some cases, cracks, which is

unfortunate.

  The present invention aims to suppress the

aforementioned problems.

  The present invention consists of an insertion piece fixing device for fixing in a fibrous material. It comprises two pieces, a first element (female) or socket and a second element (male) or insertion piece. The insert is made of

  so that it can be screwed into the socket.

  To secure the two parts, a deformable portion of the insert is stamped or deformed to penetrate a fluted portion of the sleeve. Thus, the two parts are mechanically secured. The device according to the invention subjects the surfaces of both sides of the opening to a compression effect. The arrangement obtained eliminates the aforementioned problems and partly compensates for the loss of resistance due to the creation of the opening for the implementation.

  place of the insertion part of the fixing device.

  Other features, objects and benefits of

  the invention will emerge from the detailed description which will

  follow, with reference to the annexed drawing, representing examples

  non-limiting embodiments, of which: FIG. 1 is a plan view from above of the

  socket corresponding to a preferred embodiment of the invention.

  vention; Figure 2 is a side elevation and sectional view of the bushing shown in Figure 1; Fig. 3 is a bottom plan view of the socket shown in Fig. 1; Figure 4 is a top plan view of the insertion part corresponding to the preferred embodiment of the invention; Figure 5 is a side elevation and sectional view of the insertion member shown in Figure 4; Fig. 6 is a bottom plan view of the insertion member shown in Fig. 4; Figure 7 is a side elevational view in section of a fibrous material in which is formed an opening for the placement of the device according to the invention; Figure 8 is a side elevational view in section of a fibrous material in which is practiced an alternative opening for the placement of the device according to the invention; FIG. 9 is an exploded perspective view of the

  preferred method of execution and a structure of

  fibrous; FIG. 10 is a side elevational sectional view of the preferred embodiment of the invention, before

  the joining of the two pieces; -

  Figure 11l is a side elevational view and

  section of the preferred embodiment of the invention,

  feeling the two pieces as they should appear after their joining; Figure 12 is a side elevation and sectional view of the preferred embodiment of the invention, when mounted in the opening variant shown in Figure 8; Figure 13 is a side elevational view and

  section of a second embodiment of the invention,

felt in the assembled state.

  A preferred embodiment will be described below.

  of the invention, with reference to FIGS. 1 to 6.

  positive embodiment according to the invention comprises two parts, a first (female) cylindrical element or socket 10 and a

  second cylindrical element (male) or insertion piece 20.

  As shown in Figures 1 to 3, the sleeve 10 has a first end 11, a second end 12 and a central body 13 between them. A bore 14 extends from one end to the other, a portion 15 thereof being threaded. The body 13 is delimited by an outer wall

  continues 16. The first end il1 has a shoulder-

  collar 17 with an outside diameter greater than

  to the outer diameter of the central body 13.The bore 14 comprising

  at the first end 11, a multiplicity of cane-

  18. The second end is open and

  limits the termination of the wall 16 of the body 13.

  Referring to Figures 4 to 6, we can see the representation of the structure of the insert

  corresponding to the preferred embodiment of the invention.

  The insert 20 has a first end 21, a second end 22 and a central body 19 included

  between them. A bore 23 extends from the first end

  21 at the second end 22, a portion 24 thereof

  being tapped. A plurality of opposing or

  25 are formed inside the threaded portion 24. The central body 22 is delimited by an outer wall

  continues 26 most of which is threaded. The first

  end 21 delimits the termination of the outer wall.

  26 of the central portion 22. The portion of the insertion piece 20 located at the first end 21 is constituted by a deformable material relative to

  to the material of which the sleeve 10 is made.

  The deformable element has a first frustoconical surface 28 which connects to a flat surface 27 at the top of the insertion piece and ends with a

  smooth inner surface 29 formed substantially perpendicularly

  culutely to the upper flat area 27. The second

  mité 22 comprises a shoulder or collar 31 which has an outer diameter greater than the outer diameter of the

  central portion 22 of the insert. The outer diameter

  the inside of the body 22 of the insertion piece is of a di-

  mension allowing to screw the insertion piece in the bore 14 of the sleeve 10. Preferably, the outside diameter of the collar 17 of the sleeve and that of the collar 31

  of the insertion piece are equal.

  FIG. 7 shows an orifice 32 conventionally made in a structure made of fibrous material, for mounting the device according to the invention. The structure 33 has a first surface or upper surface 34 and

  a second surface or lower surface 35.

  Figure 8 shows a structure in terms of

  Composite iron similar to that shown in Figure 7, but the orifice 32 'is supercharged at the upper surface 34' and the lower surface 35 'to provide

  a variant of a mounting aperture for the execution mode

preferred embodiment of the invention.

  Figures 9 to 13 relate to the mounting of the

  tif corresponding to the preferred embodiment of the invention.

  Figure 9 is an exploded view illustrating the placement on the fibrous panel structure. The bushing 10 is inserted into the orifice 32 by one side 34 of the structure. The insertion piece 20 is then screwed into the sleeve 10 by the opposite side 35. In the preferred embodiment, the two shoulders or flanges 17, 31 are made flush against the surfaces 34 and 35 of the panel 33 A conventional tool or key (not shown) is inserted into the slots 25 to clamp the insert and socket together by applying the desired torque for assembly. At the end of this part of the installation,

  the whole will present itself as it has been represented on the

gure 10.

  To complete the installation, so that the two parts are permanently secured, a conventional stamping tool is inserted in the fastener, at the end where the fluted portion of the sleeve 10 is

  adjacent to the deformable portion of the insertion piece 20.

  The deformable end 21 of the insertion piece 20 is then pressed or otherwise deformed to penetrate the grooves 18. The two pieces are thus secured in a single-piece device. At the end of the operation, the device is presented as it was

shown in Figure 11.

  To mount the device according to the invention in the

  variant ovalésée opening 32 ', so that the device

  Once mounted, flush the two surfaces 34 ', 35' of the fibrous structure, one proceeds in a manner identical to that described above. It is shown in section on the

figure 12 the appearance obtained.

  A second embodiment of the invention is shown in the mounted state in a fibrous structure in FIG. 13. All the features of this variant of execution are identical to those described with regard to the preferred embodiment. with one exception. A

  grooved or knurled section 40 is formed on the periphery

  The knurled section 40 has the advantage that, when the bushing 10 is pushed into the orifice 32, the flutes penetrate and become fixed in the fibrous material. The interaction between the bushing and the fibrous material is such that the bushing

  is held more firmly in place during installation.

tion.

  The present invention compresses the

  faces located on each side of the structure,

  when the sleeve and the insert are tightened one on the other.

  The lower surfaces of the collars 17, 31 constitute

  supporting surfaces in this respect. This action effectively maintains

  curing the fiber layers in place around the opening

  ture, which prevents adverse effects, such as

  cracks. The device according to the invention also maintains

  the fibers closely together in the area of the opening 32, 32 'and thus compensates for a part of the loss of strength of the structure that would otherwise result from the creation of the orifice 32. Finally, the tapping of the piece of insertion of the mounted fastener provides rigid steel tapping in a material in which

  otherwise it would not be possible to tapping satisfactorily

tory.

  It goes without saying that we can add to the descrip-

  previous version and the attached drawing of numerous amendments

  without going beyond the scope of the

  vention. The choice of the materials of manufacture of the socket

  and the insertion piece depends on the particular use of

  of the fastening device and the type of material

posite.

Claims (5)

  1. Fixing device intended to be placed   in a fibrous material, characterized in that   takes: - a first cylindrical element (10) comprising a central body (13) between two ends (11 and 12), one of these two ends (11) having an outside diameter (17) greater than that of the central body ( 13); said element being traversed right through by a bore (14); a second cylindrical element (20) having a central body (19) between two ends (21,22), one of these two ends (22) having an outer diameter (31) greater than that of the central body; said central body   having an outer diameter corresponding to the inside diameter   bore (14) of the first element (10) and being   poured through by a bore (23) provided with a file   floor (24); - means for clamping one on the other the first and the   second element after introduction of the second in the first.   2. Fastening device according to claim 1, characterized in that the clamping means on one another of the two elements consist of a thread (15) formed in the bore (14) of the first element (10). ) sure   which is screwed a thread (26) disposed on the outer wall   from the central part of the second element (20).   3. Device according to claim 2, characterized in that the end (21) of the central body (19) of the   second element (20) consists of a deformed material   mable so that it can be flared by deformation in   housing (18) provided in the first member (10).   4. Device according to claim 3, wherein said end (21) comprises a frustoconical portion (28).   - which by deformation of matter comes, by force,   in grooves (18) arranged along the perimeter   internal pheme of the end (17) of the central body (13) of the first element (10) so that the two elements   can be mechanically locked onto each other.   5. Device according to any one of the claims   1 to 4 in which the outer cylindrical wall of the   device after assembly, ie the cylindrical wall   external jig (16) of the first element (10) has a notched or knurled portion so as to fit into the wall of the orifice (32) formed in the structure (33) in which the fixing device is placed in place according to the invention.