DE2314172A1 - Three layer fibre reinforcement - fibres laid without weaving then bonded - Google Patents

Abstract

A reinforcing element consisting of fibres, or of fibres spun to form endless filaments, consists of three superimposed layers of filaments, oriented at angles differing by 60 degrees and bonded together by an adhesive esp. one having a larger rupture strain than the fibres themselves. Pref., one layer runs longitudinally like a warp thread.

Description

Reinforcing element made of fibers or threads The invention relates on a reinforcing element made from fibers or from fibers spun into continuous filaments.

Both inorganic fibers, such as glass, quartz, Asbestos or metal fibers or thin wires or the like as well as organic Fibrous materials, such as Natural and man-made fibers can be used.

It is known mats and fabrics as reinforcing elements in one Embed a matrix of reactive resins or the like or with a hardening one To provide a layer of more or less viscous or dough-like masses or them to soak in it (glass fiber reinforced plastics, Selden, Springer Verlag 1967, Page 534).

These well-known composite materials, which are made with reinforcing elements woven, knitted or similarly intertwined threads usually no longer have a smooth surface because the structure of the Tissue or loop of the reinforcement threads on it plastically outlines that is often felt to be disadvantageous.

But above all in all these cases the reinforcing property becomes of the threads are not used optimally, because in all types of weave, due to entanglement, Linking or the like, the reinforcing threads always have corrugations and curvatures must be subjected in tight radii. This will have the reinforcing effect both the individual fibers and the threads are reduced. The underlying of the invention The task is to find a reinforcing element and a suitable one for its production To propose method in which the reinforcing properties of fibers existing threads are optimally used and the disadvantages of well-known reinforcing elements be avoided The invention consists in that a reinforcing element of the type mentioned is characterized by three superimposed on one level and in it main directions to each other by 600 oriented threads, their respective Layers are fixed by means of a binder. In this way a quasi arises isotropic scrim, which z. B. with spherical deformations of the reinforcing element has a particularly favorable effect. What is also decisive is that of not having one conventional weave allowed the fibers to be fully stretched.

Reinforcing threads can also be used in the so-called winding process Process into hollow bodies, which when cut open in the direction of the winding axis and placed in a plane, also result in a scrim of a plane design. The length and width of such a mat are always dependent on the diameter and Length of the winding core used. So it is not possible to use sheet goods in this way manufacture analogous to a fabric. In addition, one inevitably arises when winding Quasi-fabric structure that leads to a waviness of the fibers. Also is the manufacture such clutches are very expensive because, among other things, lathe-like winding machines must be used.

Due to the manufacturing process, there is also a strong curvature of the whole Bobbin; it has an unfavorable effect when used to reinforce flat surfaces because the winding layer that was laid last and is on the top is longer Has reinforcing threads as the underside of a manufactured in the winding process Laid. With such reinforcement inserts naturally result differently in the company high loads on the threads on top and bottom Underside of the reinforcement mat, an optimal use of the reinforcing properties is therefore in these cases not possible.

In the case of the reinforcement element according to the invention, however, all layers of thread are of the same length, there are also no substantial ones in its manufacture Waviness or kinking of the fibers, which impair their high reinforcement effect can. Rather, it comes into its own; because the threads are all pulled taut and the matrix is about the thickness of the crosshairs.

In a further development of the invention, a binder is also proposed, which has a greater elongation at break than the reinforcing fiber used. The stretch is important for the reinforcing effect of the fibers. At the subject of the invention, the tensile strength of the resin is not fully in the load Claimed, but there is security that the tensile strength of the reinforcing element can be fully exploited.

In the context of the invention, it also includes specifying a method the application of which creates a reinforcing element fulfilling the task of the invention This method consists in that on a warp thread guided in the usual way at least one further brought in from a direction pivoted by about 60 degrees Thread is deposited and that the resulting fiber fabric with the help of a binder is fixed.

According to advantageous developments, the method according to the invention It is suggested that at least two warp beams be used to produce an endless scrim to use.

The coating of the scrim can be according to the intended purpose of the reinforcing element made with a suitable plastic in order to, for. B. later to be finally processed in the manner of anes prepreg. One can use the reinforcement element also surrounded by or embedded in a matrix.

Another advantage is the possibility of prestressing the scrim, and either only its threads running in the main direction or those in the directions deviating from the main direction.

Furthermore, the subject matter according to the invention eliminates the expense for the otherwise customary special equipment to be woven threads as well as for labor and machine hours required for weaving. The most necessary fabric finish can be saved as well as all other or necessary for weaving but appropriate pre- and post-treatment of the woven material. The reinforcement element according to the invention is furthermore free from disturbing tissue knots: it has one in cross section homogeneous fiber distribution with a uniformly flat fiber complex.

On the drawing described below, the method is in accordance with the invention explained with reference to two schematic drawings. Not from the drawing shown warp beams in the direction of arrows 19 and 20 brought up in itself parallel and practically lying in one plane thread layers 1 and 2 exist each from any number of reinforcement threads. The thread layer 2 is about r (, Compared to the thread layer 1 in the plane of the drawing, the latter becomes complicated, like it z. Bo in the making of tissues is common, tight danger and may receive a desired pretension. The thread layer 2 is attached to the outer threads of the layer 1, namely at points 3 to 10 or those previously passed Points 11 to 18 are diverted by suitable means, and the thread position also changes 21 results, and also a fixation of the layers by means of a binder Basically there are four different indentations at the crossing points of the thread layers in question: a) binding, as with nonwovens b) needling known per se with or without a support c) sewing d) chemical bond, analogous to that ei fiberglass chip mats.

According to FIG. 2, the orientation of the threads is determined by the coordination of the Draw-off speeds of the thread 1 according to FIG. 1 = V1 with the thread layer 2 according to Fic 1 = V2 can be influenced as required and can be changed during production, so that the structure of the reinforcement element is adapted to its later intended use Can be grounded - claims -

Claims (9)

Claims 1. Reinforcing element made of fibers or of continuous filaments spun fibers, indicated by three superimposed on one level and in their main directions to each other about 600 oriented threads, their respective Layers are fixed by means of a binder. 2. Reinforcing element according to claim 1 g e k e n n -z e i c h n e t by a binder, which has a greater elongation at break than that for Application of reinforcement fiber. 3. Reinforcing element according to claims 1 and 2, characterized g e k It is noted that on a thread deposited in the manner of a warp thread about 600 deviating from the main direction further threads are deposited and the scrim coated with plastic or embedded in a matrix. 4. Process for the production of a reinforcing element according to the Claims 1 to 3, characterized in that on one in the usual Way guided warp thread at least one from a direction pivoted by about 600 brought up further thread is deposited and that the resulting fiber structure is fixed with the help of a binder. 5. The method according to claim 4 g e k e n n z e i c h n e t by the Use of at least two warp beams. 6. The method according to claims 4 and 5 g e k e n n -z e i c h n e t by coating the fabric with synthetic resin. 7. The method according to claims 4 and 5 g e k e n n -z e i c h n e t by embedding the scrim in a matrix. 8. The method according to claims 4 to 7 g e k e n n -z e i c h n e t through further processing of the scrim as prepreg. 9. The method according to claims 1 to 8, characterized in that g e -k e n n z e i c h n e t that the scrim is at least partially pretensioned.