DE1938554A1 - Rod with high flexural strength and application of the same - Google Patents

Description

Rod with high flexural rigidity and application of the same

The subject of the present invention is a prismatic rod with high bending stiffness.

It is known that rods depending on the cross-sectional shape with a certain cross-sectional area and certain material very can have different specific bending stiffnesses. The bending stiffness of a rod in relation to a certain direction is the product of the moment of inertia of the cross-sectional area in relation to the corresponding neutral axis and the Ε module of the materials used.

Particularly high demands are placed on bars for a wide range of applications in terms of the highest possible flexural rigidity with low weight. This is common in the .building technology and in machine and apparatus engineering, especially for dynamically stressed bars of l'all.

009814/1284

According to the invention, in spite of a prismatic rod low weight a high bending stiffness achieved in that a prismatic lightweight support rod along its longitudinal edges with edge reinforcements made of a material with a substantial relative to the Ε module of the material of the lightweight bearing rod higher 'Ε module is connected.

Using this inventive principle, it is possible to use a prismatic lightweight support rod, which in itself only with regard to one for the intended use of the to be manufactured Rod has sufficient resistance to the expected static shear and pressure loads and the lowest possible weight is designed to meet the mega-stiffness required for the particular application to give the central planes of symmetry of the prismatic rod profile that along the longitudinal edges of the support rod suitable profiled and dimensioned edge reinforcements made of material with a correspondingly high Ε module. Since the cross-sections of such edge reinforcements are natural the greatest possible radial distance from the central axis of the rod and thus also the greatest possible surface inertia ; moment, when using materials with bej especially high Ε module, especially steel, even with small ones; Cross-sectional dimensions of such edge reinforcements are very high

Flexural stiffnesses can be achieved without the improvement . the bending stiffness requires a lot of additional weight.

The invention also relates to the particularly advantageous one Use of a rectangular bar according to the invention as a support bar in a heald frame, which is then advantageously is also to be designed as a carrier for a heald lined up bar.

ÖÖ9 8147T2 9A

Purely heald frame is namely the observance of the promotion after the smallest possible weight with the highest possible flexural rigidity or dimensional rigidity particularly essential if a high working speed, i.e. high stroke frequencies, is to be achieved. The one necessary to drive the heald frames Energy grows proportionally to its weight and to the square of the speed of movement and must be supplied by correspondingly powerful motors. on the other hand and bending of the shaft rods due to insufficient porosity, i.e. flexural rigidity of the same, is the cause puncture disorders, because they are the upsetting and / or tearing of the healds attached to the heald frame can cause. In addition, the minimum weight and maximum flexural rigidity of mechanical components mean that the Natural frequencies of the components in question are increased, whereby the excitation of resonance vibrations in the first place starts with corresponding high-frequency dynamic loads.

Preferred embodiments of the subject matter of the invention are shown in the drawing. It shows in cross section:

Fig. 1 shows a first embodiment

Pig. 2 one designed as a support rod of a heald frame Rod according to the invention

PIg. 3 shows a further embodiment with a one-piece Cell structure as a supporter of the edge reinforcements.

The rod shown in Pig «1 comprises a lightweight support rod 1 in the form of a Mchtmetallhohlprofils with the cavity 1o. There are recesses on the longitudinal edges of the tiohl profile

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0098U / T294

121, 122, 123, 124 to accommodate angularly profiled edge reinforcements 21, 22, 23, 24 made of high-quality steel or other material with a particularly high Ε module. These edge reinforcements are along their entire length connected to the light metal hollow profile, preferably glued in its edge recesses with high-quality adhesive.

The thicknesses and lengths & er edge reinforcement angle profiles are the required flexural strengths in the specific case adjust in the two main directions of the rod, with superfluous material to keep the total weight low is to be avoided. The external dimensions are similar and the wall thicknesses of the light metal hollow profile 1 as much as possible in the interest of saving weight to be kept low, but without the necessary pressure and shear strengths are not reached. In many cases, the cavity 1o can be filled with supporting material 11 of the lowest possible specific weight, i.e. a maximum of 0.5 kg / which contribute to an improvement of the rod.

The rod of Fig. 2 is formed as a supporting rod for a heald frame, and the hollow profile 1 is provided for this purpose on the one narrow side with a molded-I ⁿ ragsteg 1 'for a healds-Aufreihschiene 12th Otherwise, the design of the rod according to FIG. 2 corresponds to that of the rod according to FIG. 1 with the small one. Modification that as edge reinforcements 21, 22, 23, 24 instead of ^ angle profiles, flat profiles made of high quality steel are glued into corresponding edge recesses 121-124 of the light metal hollow profile.

Fig. 3 shows an embodiment with a square Cross-section, as a lightweight strut 1. It consists preferably

009814/1294

made of round, mutually connected foam grains, or hollow spheres with a relatively small outer diameter. The older Swiss patent specifications No. 436 696 and Mo. 464.5o7 disclose a method for producing such 2-cell structures. For example, round foam grains made of expanded polystyrene are first mixed with liquid epoxy resin or other synthetic resin adhesives that do not split off any volatile constituents during thermal curing, and then with fine 3? Est powder or with short fiber material, whereby a free-flowing mass of externally dry, but adjustable fret grains arises, which can be pressed in a mold to a specifically light cell structure with relatively excellent moisture properties. The resulting polyhedral cell walls are cured under the influence of increased temperature, possibly with simultaneous gluing with cover layers and / or inserted reinforcement parts in the press mold. In the German patent application P 19 17 362.7 other possibilities for the production of specifically light cell structures of high quality in terms of strength and other properties are disclosed. By mixing hollow microspheres {0 α 0.05 mm) based on phenolic resin or expanded but small ¹ polystyrene grains (0 τ * & 1 - 2 mm) with liquid, thermally curable course resin, preferably epoxy resin and possibly also with short thin ones Glass fibers (0 1-2 mm), {0 , o1 mm) a plastically deformable, adhesive, but non-sticky mass can be produced, which can be deformed and thermally hardened in a: Press mold with adhesive bonding with cover layers and reinforcement inserts. With the methods and means described above, light, mechanically stable cell structure rods according to fig. 3 together lengthways

_ 6 0098ΊΪ7Ί2 94

the edges embedded in it round or otherwise profiled edge reinforcements 21-24 and a glued-on, abrasion and local pressure resistant outer layer 3 »zH based on epoxy resin with or without glass insert or made of a metal foil.

Expectations;

0098U / 1294

Claims (8)

Expectations Prismatic rod with high flexural rigidity, characterized in that a prismatic lightweight support rod (1) along its longitudinal edges with edge reinforcements (21-24) made of a material with relative to the E-hodul des Material of the lightweight support rod is connected to a significantly higher Ε module. 2. Rod according to claim 1, characterized in that a lightweight support rod (1) with a basically rectangular cross-section along its outer edges for receiving recesses of glued-in edge reinforcements (21 - 24). 3 · rod according to claim 2, characterized in that a light metal hollow profile is used as a lightweight support rod (Fig. 1, 2). 4. Rod according to claim 3 »characterized in that Cavities of the light metal hollow profile (1o) with supporting material (11) of a specific weight of at most 0.5 kg / dnr are filled out. 5. Rod according to claim 1, characterized in that the lightweight support rod {A) consists essentially of a one-piece cell structure, which are provided with edge reinforcements (21-24) made of material with a relatively high Ε module (Fig. 3), 6. Rod according to claim 5, characterized in that the outer surfaces of the cell structure rod (1) are provided with a scnutzbelag {3) to improve the mechanical resistance (Fig. 3). · . - 8 00981 Λ 712 94 7. application ring of the rod according to claims 1-6 as a support rod in a heald frame. 8. Use according to claim 7, characterized in that the rod is used as a carrier for a heald heald bar (.12) is formed (Pig. 2). The patent attorney 009814/129 4