RU2791942C1 - Method for manufacturing composite power element - Google Patents

Abstract

FIELD: power element production.

SUBSTANCE: manufacturing parts from composite materials, namely a power element - a rod having mounting holes at opposite ends. The method includes winding bundles of continuous reinforcing fibres impregnated with a binder onto two annular mandrels using a spreader moving around the support pins along an oval trajectory and reciprocating along the axes, forming a closed belt. Then the reduction of two straight sections of the closed belt into a continuous section with the formation of a rod, the tension of the resulting element, polymerization, tension relief and removal of the finished product from the pins. Moreover, the end caps are moulded in one piece with the product from the same fibrous material as the rod itself, by winding the first, then the second end caps alternately on the removable annular mandrels. After that, a closed belt is wound around two ends, two or more blanks can be wound in series, after winding at least one of the pins rotates around the product axis at an angle that is a multiple of 180 degrees, and at the last turn at an angle from 0 to 180 degrees, with forming a plane of the first and second ends, rotated relative to each other at an angle from 0 to 180 degrees. In this case, two straight sections of a closed belt are twisted with the formation of a rod and at the same time with its tension, after polymerization, tension release and removal of the finished product from the pins, the extraction of the ring mandrels from the end caps, and the reinforcing bundles can be made of mineral glass, basalt, carbon, organic, natural, plant and synthetic polymer fibres.

EFFECT: reduction of labour intensity, the simplification of the manufacturing method and the increase in reliability in comparison with analogues.

1 cl, 3 dwg

Description

The invention relates to a method for manufacturing parts from composite materials, namely a power element - a rod having mounting holes at opposite ends.

Products made by the proposed method can be used in electrical engineering as composite stretch marks, rods for electrical insulators, in mechanical engineering and automotive industry as a thrust, in aviation as an integral element of the chassis.

A known method of manufacturing thrust from a composite material containing reinforced ends [RF Patent No. 2499669, publ. November 27, 2013]. A method for manufacturing a rod from a composite material with reinforced ends includes the steps of manufacturing a mandrel containing a sleeve made in the longitudinal direction and reinforcing inserts rigidly connected to the ends of this sleeve, forming a rigid system around this mandrel, which is moved in the longitudinal direction by a machine for weaving reinforcing fibers surrounding it along its entire length, one or more layers of fiber braid are made, resin is injected and polymerized to provide adhesion and a rigid connection between the layers of fiber braid and at least the ends of the mandrel to form a traction housing with reinforced ends. At each end of the traction housing, a transverse hole is drilled, passing through the layers of fiber braid, as well as through the insert.

The disadvantages of this method is the need to pre-create a mandrel and additional drilling of holes for thrust, which violates the structure of the composite and reduces its mechanical strength and increases the complexity of manufacturing parts.

Also in the invention described above [RF Patent No. 2499669, publ. 11/27/2013] mentions a method for manufacturing a strut link, containing a tubular section made of aluminum, at the ends of which two tips are fixed, which are massive metal parts made by casting or forging, containing a hole and forming, each, an eye. The tubular design of the rod body provides its optimal resistance to deflection, while the tips, given the large amount of material they contain, provide the necessary collapse resistance. To reduce the weight of such a rod, as is known, the central tubular housing of the rod is replaced by a central tubular housing made of a composite material, for example, based on carbon fibers.

The disadvantage of the known part is that it has a sufficiently large mass, since the tips are metal and are decisive for the mass of the entire thrust, given the amount of material contained in them. When replacing the central tubular body with a composite one, the complexity of manufacturing the part increases, caused by the need to connect dissimilar materials and control the quality of the connection, the metal-composite junction creates a stress concentration and inevitably reduces the strength of the structure.

Known mechanical part and method of its manufacture [RF Patent No. 2398056, publ. 27.08.2010]. The mechanical part is intended to be articulated with other parts at their end points, for example as a landing gear support lever. The part is made of composite materials and consists of a fibrous central preform made from a three-dimensional fabric and a fibrous peripheral preform made from a three-dimensional fabric. The central and peripheral preforms are attached to each other by tie wires, with each tie wire passing through each of the preforms, or at least a portion of them. The resulting mechanical part has a small mass and can withstand loads well.

The main disadvantage of this invention is that the individual elements of the part, namely the inserts and molded blanks, are made separately, which makes the part demountable and reduces its reliability, and also increases the complexity of manufacturing.

Closest to the proposed invention (analogue) is the author's certificate N 1753496, B.I. N 29, 1992. A well-known insulating bearing element contains a straight rod section and two end sections made of continuous strands impregnated with a binder of glass fibers, two end caps (which may be fiberglass bushings) that are covered by the end sections, as well as a transverse layer of glass fibers enclosing a straight rod section. The method of manufacturing known insulating carrier element is as follows. Two end fittings in the form of support bushings are mounted on two support pins. With the help of a spreader moving around the support pins along an oval trajectory and performing reciprocating movements of the layout along the axes, the glass bundles impregnated with a binder are wound onto the support bushings, forming a closed belt. Crimping of end caps is carried out, the reduction of two straight sections of a closed belt into a continuous section (organization of the rod). The tension of the resulting element is carried out using hydraulic cylinders. Then, with the help of a drive shaft, the resulting element is rotated around its longitudinal axis and winding of transverse glass bundles impregnated with a binder is carried out using the reciprocating movement of the spreader along the longitudinal axis of the element. After that, the polymerization of the binder is carried out, tension is released and the finished product is removed from the fingers.

The disadvantages of the known method include the complexity of manufacturing the product, the need to use additional equipment (hydraulic cylinders for tensioning, a drive shaft and a spreader for applying a transverse reinforcing layer), insufficient reliability during long-term operation under tensile load, since in this case the formed rod will tend to its original state. in the form of two straight sections, and the load on the transverse retaining layer will increase, which may collapse over time.

The technical objective of the invention is to create a method for manufacturing a composite power element, devoid of the above disadvantages inherent in known technical solutions: reducing labor intensity, simplifying the manufacturing method and increasing reliability compared to analogues.

The technical problem posed is solved by the fact that in the method of manufacturing a composite power element, including winding impregnated with a binder bundles of continuous reinforcing fibers on two annular mandrels using a spreader moving around the support pins along an oval trajectory and reciprocating along the axes, forming a closed belt , bringing two straight sections of a closed belt into a continuous section with the formation of a rod, tensioning the resulting element, polymerization, relieving tension and removing the finished product from the fingers, the end caps are formed in one piece with the product from the same fibrous material as the rod itself, by winding on the extractable annular mandrels in turn of the first then the second end caps, after which a closed belt is wound around two end caps, two or more blanks can be wound in series, after winding at least one of the fingers rotates around the axis of the product at an angle multiple of 180 degrees, and on the last turn at an angle from 0 to 180 degrees, with the formation of the plane of the first and second ends, rotated relative to each other at an angle of 0 to 180 degrees, while two straight sections of a closed belt are twisted with the formation of a rod and at the same time its tension , and reinforcing tows can be made of mineral, glass, basalt, carbon, organic, natural, vegetable and synthetic polymer fibers.

The essence of the invention is illustrated by drawings (Fig. 1 - 3) with a brief description. Designations on the drawings: 1, 2 - ends; 3 - rod; 4 - fibrous reinforcing material; 5, 6 - ring mandrels; 7 - fixture; 8, 9 - fingers; 10 - spreader.

In FIG. 1 shows a composite power element obtained by the claimed method, which consists of two ends (1, 2) and a twisted profile rod (3), made of the same material in one technological cycle.

In FIG. 2 and 3 show the sequence of execution of the method for manufacturing a strength element. The method of manufacturing a composite power element is as follows. The product manufacturing process includes winding continuous reinforcing fibers (4) pre-impregnated with a thermosetting binder onto two annular mandrels (5, 6) fixed on fixture (7) with fingers (8, 9). The mandrels are spaced apart by a distance determined by the length of the part and serve to form end caps (1, 2) with holes. Winding is carried out on winding machines, mainly equipped with a numerical control system, and the manufactured part is located along the main axis of rotation at a certain distance from the center of rotation, determined by the design of the device (7).

First, the first end cap (1) is wound onto the annular mandrel (5) by synchronized reciprocating motion of the spreader (10) and oscillating (oscillatory) rotation of the fixture (7), then the spreader (10) moves to the second annular mandrel (6) and the second one is wound end cap (2) similarly to the first. Then, the reinforcing fibrous material (4) is wound on both annular mandrels (5, 6) using a spreader (10) moving around the mandrels (5, 6) mounted on the support pins (8, 9) along an oval trajectory and reversing - translational movements along the axes of the mandrels, forming a closed belt, up to the set of the required transverse size of the rod (Fig. 2). Next, the mandrel turns and the second workpiece is wound according to the above scheme. Two or more workpieces can be wound in series. At the end of the winding process, the fastening of the pin (8 or 9) of one of the two annular mandrels (5, 6) is loosened, one of the fingers rotates around the axis of the product at an angle multiple of 180 degrees (Fig. 3), and at the last turn, at an angle from 0 to 180 degrees, with the formation of the plane of the first and second ends, rotated relative to each other at an angle from 0 to 180 degrees, while the reinforcing material is twisted to form a rod (3). As the rod (3) is twisted, the length of the power element (the distance between the ends) decreases and, at the same time, the rod is tensioned. The pins (8, 9) of the annular mandrels (5, 6) are fixed with a certain force, providing the required tension of the reinforcing material in the core part of the part. The thermosetting binder is cured in accordance with the accepted temperature-time conditions, after which the tension is released, the pressurization and removal of the removable ring mandrels from the end caps and the finished product is removed.

The proposed method for manufacturing a composite power element is simple and less labor intensive compared to analogues, and makes it possible to obtain a product from one material without using the assembly operations of the end cap and the rod, in one technological cycle. The product is completely composite, has no metal parts and a connection surface of dissimilar materials. Unlike analogues, the rod is formed by twisting with simultaneous tension, and after polymerization it is fixed in this state, without the need to apply annular transverse layers to maintain the shape of the rod. The mechanical and operational characteristics of the power element and its reliability are improved.

The developed method for the manufacture of a composite strength element can be used in various industries - in electrical engineering for the manufacture of rods and terminations of polymeric electrical insulators, electrically insulating stretch marks, suspensions and other strength elements from composites, in mechanical engineering and construction - for the manufacture of traction, cable-stayed braces, ropes and their terminators, for creating prestressed concrete structures, fastening formwork, in the aircraft industry - for the manufacture of chassis elements and other load-bearing parts from composites.

Claims (1)

A method for manufacturing a composite power element, which includes winding bundles impregnated with a binder from continuous reinforcing fibers on two annular mandrels using a spreader moving around the support pins along an oval trajectory and reciprocating along the axes, forming a closed belt, bringing two straight sections of the closed belt into solid section with the formation of a rod, tension of the resulting element, polymerization, tension relief and removal of the finished product from the fingers, characterized in that the end caps are formed in one piece with the product from the same fibrous material as the rod itself, by winding on removable ring mandrels alternately the first, then the second ends, after which a closed belt is wound around two ends, two or more blanks can be wound in series, after winding at least one of the fingers rotates around the axis of the product at an angle that is a multiple of 180 degrees, and at the last turn ote at an angle from 0 to 180 degrees, with the formation of the plane of the first and second ends, rotated relative to each other at an angle of 0 to 180 degrees, while two straight sections of a closed belt are twisted with the formation of a rod and at the same time its tension, after polymerization, reset tension and removal of the finished product from the fingers, the extraction and removal of the removable ring mandrels from the ends are performed, and the reinforcing bundles can be made of mineral glass, basalt, carbon, organic, natural, plant and synthetic polymer fibers.

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