RU2481237C1 - Method of making curved cellular structure spoke from composite materials and curved cellular structure spoke from composite materials - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: set of invention relates to aerospace engineering and may be used for making reflector frames, manipulator beams, etc.Proposed method comprises applying separation layer of unfast material with cross-section defined by intersection of two lateral surfaces and two curvilinear surfaces, outer cylindrical and inner toroidal surfaces. Four grooves to laying bundles of the spoke main lengthwise ribs are made at intersections of all surfaces. Grooves for extra lengthwise ribs are made on cylindrical and toroidal surfaces while helical grooves of both coiling directions for bundles of spoke helical ribs are made on all surfaces. Helical grooves on curved, cylindrical and toroidal surfaces are made to ensure coiling angle φ₀ between tangent to coiled bundle and tangent to curvilinear surface generatrix, on lateral surfaces in transition from plane to curved surface with coiling angle between bundle being coiled and normal to curved surface guide circle φ₀, while in transition from curved surface to plane - (φ₀+Δφ), with φ₀ equal for all surfaces of the mandrel.

EFFECT: higher operating characteristics.

6 cl, 10 dwg

Description

The invention relates to the aerospace industry and can be used to create skeletons of reflectors, boom manipulators, as well as skeletons of domes of minimum weight and increased requirements for rigidity.

Known mesh shells of circular cross section according to patent US 3940891 A from 03/02/1976, MCP ⁷ B64G 1/22, patent RU 2189907 from 06/26/2000, MCP ⁷ B32B 3/12, patent RU 2392122 from 05.11.2008, MCP ⁷ B32B 1 / 08, application WO 9307412 A1 of 04/15/1993, MCP ⁷ B32B 1/08, patent RU 2153419 of 03/10/1999, MCP ⁷ B32B 1/08, patent RU 2149761 of 03/03/1999, MCP ⁷ B32B 1/00, US patent 4137354A dated 1/30/1979, INC ⁷ B32B 1/00. Known long mesh shells of rectangular cross section according to utility model RU 89070 from 09/03/2009, MKP ⁷ B64C 1/08, utility model RU 89069 from 09/03/2009, MKP ⁷ B64C 1/08.

The listed mesh shells are formed by a system of longitudinal, annular and spiral both directions of the ribs of circular and rectangular profiles and are made of unidirectional bundles of high modulus fibers impregnated with a synthetic binder. The main feature of all the mentioned methods and designs is that the line of centers of the cross section of the shells is a straight line, and the spiral ribs are wound with a constant winding angle ± φ. Shell rectangular profile formed by the intersection of four planes.

Known technical solutions that determine the achieved level of technology in a simple class of shells cannot be extended to structures with a curved line of centers and are not particularly relevant. Therefore, the proposed solutions eliminate the disadvantages of the General prior art.

The disadvantage of the prior art for the method is as follows.

When winding spiral ribs of a curved spoke of a rectangular profile, the outer surface of which is formed by the intersection of two side planes and two cylindrical surfaces, with a constant winding angle (see Fig. 6) equal to the initial φ ₀ (for cylindrical surfaces φ is the angle between the tangent to the winding spiral rope and tangent to the generatrix of this cylindrical surface, for planes φ is the angle between the winding straight-line tourniquet and the normal to the guiding circle of the cylindrical surface), spiral amotka degenerates into an annular and spiral fins winding becomes impossible. This is because when winding on the lateral plane, the normal vector changes its position with each step of the winding.

From the point of view of spiral winding of a concave cylindrical surface, it has a negative curvature, and the trajectory of the bundle when it is tensioned is a straight line over the concave surface of the mandrel, i.e. the winding of these segments of spiral ribs occurs with no contact with the surface of the mandrel (see figure 3), that is, without contact pressure, and the structure of the ribs is loose, which reduces the bearing capacity of the structure.

When using a curved needle as an element of the mirror reflector frame with a working surface formed by spraying a mirror material onto a sheet material (flexible film), the known methods cannot provide (due to the natural spread of the elastic modulus of the material, thicknesses, etc.) the elastic the lines of the spokes of a set of several spokes, that is, the same deformation of the console of each spoke of the frame under a given bending load (a given bending stiffness in very narrow limits), which leads to perceptible distortion of the mirror under operational loads.

A disadvantage of the prior art for the device is as follows.

A curved rectangular-shaped spoke made using well-known features of known devices, for example, for a spoke with a constant angle (see Fig. 6) φ (here is the angle between the spiral rectilinear edge of the side plane and the normal to the corner edge), the frequency of arrangement of the spiral ribs on the lateral planes of the spoke increases, the angle (β) (see Figs. 5, 6) between the spiral ribs of both directions of the lateral planes increases (the optimum value is β≈90 °), and the reliability of the cantilever spoke, which is loaded mainly by bending effort is greatly reduced, in addition, increased design weight predominantly in the direction of the free end of the console, which also negatively.

The spiral ribs of the inner cylindrical surface have a loose structure due to the lack of contact pressure during manufacture (winding and heat treatment), which reduces the reliability of the spoke due to a decrease in its bearing capacity.

When using a curved needle as an element of the mirror reflector frame with a working surface formed by spraying the mirror material onto a sheet material (flexible film), known devices (due to the natural spread of the elastic modulus of the material, thicknesses, etc.) cannot ensure the elastic lines of consoles of each spoke of the frame under a given bending load (a given bending stiffness in very narrow limits), which leads to unacceptable distortion of the mirror under operational loads.

The technical problem to which the claimed invention is directed is the development of the design and manufacturing technology of knitting needles, eliminating these disadvantages.

The technical result for the method, which can be obtained by solving the technical problem, consists in increasing its manufacturability and the quality of the spoke by winding spiral ribs on the lateral planes of a curved needle with stepwise adjustment (see Fig. 6) of the winding angle φ, due to winding of spiral ribs on the inner curved surface of the needle with contact pressure while eliminating the concavity of the mandrel under the wound harnesses of the ribs, and also due to the possibility of optimizing the bending stiffness of the spoke no.

The technical result for the device, which can be obtained by solving the technical problem, is to increase the reliability of its operation due to the location of the spiral ribs on the lateral planes with a stepwise change (see Fig.6) of the angle (φ) between the spiral rectilinear edge of the lateral plane and the normal to the angular rib, by ensuring the approximation of the angle (β) (see Figs. 5, 6) between the spiral ribs of both directions of the lateral planes to the straight line, and also by eliminating the looseness of the spiral ribs on a concave curvilinear rotation Nost spokes. In addition, the technical result is the optimization of the bending stiffness of the spokes along its length, as well as weight reduction, mainly in the direction of the free end of the console.

The problem with the achievement of the technical result is solved by the fact that the method of manufacturing a curved needle from composite materials, in which a dividing layer of easily removable material is applied to a rigid curved mandrel, the profile of which is set by the intersection of two side planes and two curved, outer cylindrical and inner torus surfaces, at the intersections of all surfaces, four grooves are made for laying the bundles of the main longitudinal ribs of the spoke, on a cylindrical and torus surface - of the groove for the additional longitudinal edges and on all the surfaces - the spiral grooves in both directions for filament winding spiral fins spokes, wherein the spiral groove on the curved, cylindrical or torus, surfaces operate with software winding angle φ ₀ between the tangent to the take-up coil wiring and the tangent to forming a curved surface, on the lateral planes when switching from a plane to a curved surface - with ensuring the winding angle between the wound bundle and the normal to the defining circumference of this curved surface is φ ₀ , and when passing from a curved surface to a plane, it is (φ ₀ + Δφ), ensuring equality φ ₀ for all surfaces of the mandrel, while Δφ is determined by the formula:

,

,

;

, где:

;

where:

x ₀ , y ₀ - coordinates of the center of the transition circle on the plane to which the wound edge belongs;

x _n , y _n - coordinates of the point on the plane from which the edge comes out;

x _{n + 1} , y _{n + 1} - coordinates of the end of the edge in the plane,

wherein the generatrix of the torus radius r is determined by the formula:

r <R _int · ctg ² φ ₀ , where:

R _vn is the radius of the guide circle of the torus surface;

φ ₀ is the angle of winding between the wound tourniquet of the rib and the tangent to this generatrix of the circumference of the torus surface,

Then, bundles of unidirectional polymer fibers impregnated with a synthetic binder are wound in layers into the grooves with the provision of winding parameters for obtaining a mesh structure of the spoke and ensuring the straightness of the segments of the longitudinal ribs on the torus inner surface of the spokes, the segments of spiral ribs on the lateral planes, the curvature of the longitudinal ribs of the outer cylindrical surface and the convexity of the segments of the spiral ribs on the cylindrical and torus surfaces, after curing the binder, the knitting needle is stripped Yelnia layer is removed from the mandrel and spokes removed from the separation layer.

The specified bending stiffness of the knitting needles of the set is experimentally selected by the method of symmetric cutting of sections of additional ribs on each spoke during its testing.

The cross-sectional area of the main longitudinal rib is performed at least 4-5 times more than the spiral and additional longitudinal.

For the device, the task with the achievement of the technical result is solved by the fact that a curved needle made of composite materials, the profile of which is defined by the intersection of two lateral planes and two curved, outer cylindrical and inner torus surfaces, including wiring harnesses made of unidirectional with the formation of a cellular structure synthetic fiber polymer fibers four main longitudinal ribs located at the intersection of all surfaces located on a curvilinear GOVERNMENTAL surfaces of the additional longitudinal edges and disposed on all surfaces of the spiral ribs in both directions, wherein the helical ribs on the curved, cylindrical or torus, surfaces arranged at an angle φ ₀ between the tangent to the rib and tangential to the generatrix of the curved surface on the side planes in the transition from the plane on curved surface - at an angle between the edge and the normal to the guiding circle of this curved surface - φ ₀ , and when changing from a curved surface to a plane b - (φ ₀ + Δφ), ensuring equality φ ₀ for all surfaces of the spokes, while Δφ is defined by the formula:

,

,

;

, где:

;

where:

x ₀ , y ₀ - coordinates of the center of the transition circle on the plane to which the edge belongs;

x _n , y _n - coordinates of the point of origin of the edge in the plane;

x _{n + 1} , y _{n + 1} - coordinates of the end of the edge in the plane,

wherein the generating radius of the torus r is defined by the formula:

r <R _int · ctg ² φ ₀ , where:

R _vn is the radius of the guide circle of the torus surface;

φ ₀ - the angle between the edge and the tangent to the generatrix of the circumference of the torus surface.

The set bending stiffness of the knitting needle of the set is experimentally selected by the method of symmetric cutting of sections of additional ribs on each spoke during its testing.

The cross-sectional area of the main longitudinal rib is made at least 4-5 times larger than the spiral and additional longitudinal.

Distinctive features for the method are the following features:

- the separation layer profile is set by the intersection of two lateral planes and two curved, outer cylindrical and inner torus - the signs are significant, they include the presence of new operations and their new execution, aimed at solving the problem with achieving a technical result, to improve the manufacturability of the method by winding spiral ribs on the inner curved surface of the spoke with the exception of the negative curvature of the winding path;

- spiral grooves on the lateral planes during the transition from a curved surface to a plane are performed to ensure the winding angle between the wound bundle and the normal to the guiding circle of this curved surface is (φ ₀ + Δφ), while Δφ is determined by the formula:

,

,

;

, где:

;

where:

x ₀ , y ₀ - coordinates of the center of the transition circle on the plane to which the wound edge belongs;

x _n , y _n - coordinates of the point on the plane from which the edge comes out;

x _{n + 1} , y _{n + 1} - coordinates of the end of the edge in the plane -

- significant signs, include the availability of new parameters of the process operations, aimed at solving the problem with achieving a technical result, at improving the manufacturability of the method with providing its parameters and the possibility of spiral winding without degeneration into a ring due to winding of spiral ribs on the lateral planes of a curved spoke with stepwise adjustment (see Fig.6) of the winding angle φ;

- forming the radius of the torus r is determined by the formula:

r <R _int · ctg ² φ ₀ , where:

R _vn is the radius of the guide circle of the torus surface;

φ ₀ - the angle of winding between the wound tourniquet of the rib and the tangent to this generatrix of the circumference of the torus surface -

- the sign is significant, provides for the availability of new parameters of operations of the technological process, is aimed at solving the problem with achieving a technical result, at increasing the manufacturability of the method by winding spiral ribs on the inner curved surface of the spoke with contact pressure, which improves the quality of the spoke by eliminating the friability of spiral ribs on the concave surface of the knitting needle;

- the specified bending stiffness of the knitting needles of the set is experimentally selected by the method of symmetric cutting of sections of additional ribs on each spoke when it is tested - the signs are significant, they include the presence of new operations, a new sequence of their execution and their new performance, aimed at solving the problem with achieving a technical result - improving manufacturability the method due to the possibility of optimizing the bending stiffness of the knitting needles along its length and selecting spokes of the same stiffness to ensure no tviya distortion reflector mirror;

- the cross-sectional area of the main longitudinal ribs is performed at least 4-5 times more than the spiral and additional longitudinal ribs - the signs are significant, they include the presence of new operations and their new execution, aimed at solving the problem with achieving a technical result, to improve the manufacturability of the method and the quality of the spoke due to the possibility of optimizing its bending stiffness with minimal weight.

Distinctive features for the device are the following features:

- the profile of the spokes is given by the intersection of two lateral planes and two curved, outer cylindrical and inner torus surfaces, the signs are significant, they provide a new shape of the elements and their new relative position, aimed at solving the problem with achieving a technical result, to increase the reliability of the structure due to exclusion of friability of spiral ribs on a concave surface of a spoke;

- spiral ribs on the lateral planes during the transition from a curved surface to a plane are located at an angle between the edge and the normal to the guiding circle of this curved surface - (φ ₀ + Δφ), with Δφ defined by the formula:

,

,

;

, где:

;

where:

x ₀ , y ₀ - coordinates of the center of the transition circle on the plane to which the edge belongs;

x _n , y _n - coordinates of the point of origin of the edge in the plane;

x _{n + 1} , y _{n + 1} - coordinates of the end of the edge in the plane -

- the signs are significant, provide for a new mutual arrangement of the elements and a new ratio of sizes, aimed at solving the problem with achieving a technical result, increasing the reliability of the structure by arranging spiral ribs on the lateral planes with a step-by-step change (see Fig. 6) of the angle (φ ) between the spiral rectilinear edge of the lateral plane and the normal to the angular rib, due to the approximation of the angle (β) between the spiral ribs of both directions of the lateral planes to the straight edge Moreover, the sign is aimed at reducing weight, mainly in the direction of the free end of the console;

- the generating radius of the torus r is defined by the formula:

r <R _int · ctg ² φ ₀ , where:

R _vn is the radius of the guide circle of the torus surface;

φ ₀ - the angle between the edge and the tangent to the generatrix of the circumference of the torus surface -

- the sign is significant, provides a new ratio of sizes, aimed at solving the problem with the achievement of a technical result, to improve the reliability of the structure by eliminating the friability of spiral ribs on the concave surface of the spokes;

- the specified bending stiffness of the knitting needle of the set is experimentally selected by the method of symmetric cutting of sections of additional ribs on each spoke during its testing - the signs are significant, provide for a new mutual arrangement of the elements and the removal of known elements aimed at solving the problem with achieving a technical result, increasing the reliability of the structure due to optimization of the bending stiffness of the spokes along its length, as well as weight reduction, mainly in the direction of the free end of the con and;

- the cross-sectional area of the main longitudinal rib is made no less than 4-5 times larger than the spiral and additional longitudinal rib - the sign is significant, provides a new ratio of sizes, is aimed at solving the problem with the achievement of a technical result, to improve the reliability of the structure by optimizing the bending knitting stiffness, as well as weight reduction.

To prove the materiality of the features of inventions represented by formulas, the mathematical conclusions of these formulas are given.

To derive the formula for stepwise adjustment of the spiral winding angle

, где

;

,

where

;

,

consider winding spiral ribs, see Fig.7.

A straight line corresponding to a spiral edge passing through a point with coordinates, for example, x _n , y _n , is described by a well-known equation (see A.E. Tsikunov. Mathematics Collection, 2008, p. 55): yy _n = a ₁ (x-x _n ), where a ₁ = tan α ₁ . A straight line passing through the point x _n , y _n in the direction normal to the circumference of the cylindrical part is described in the same way yy _n = a ₂ (x-x _n ).

.The angle between two straight lines according to the cited reference (p. 55)

.

;

.Define a ₁ and a ₂ through the projection of lines, Fig.7. Obviously

;

.

From Fig.7 it follows that α ₂ > 90 ° and tgα ₂ <0, respectively, and y _n -y ₀ <0.

The above arguments prove the correctness of the formula for stepwise correction of the spiral winding angle.

To derive the formula for the generatrix of the torus surface radius r <R _int · ctg ² φ ₀ , the cross section of which is described by the equation:

,R = r (t + sinυ), where

,

consider winding spiral ribs on a torus surface, see Fig. 8, 9.

Contact pressure will be provided during winding if the curvature of the thread (tow) wound with tension is positive. The curvature of the bundle K _n can be determined by the well-known Euler formula (see A.V. Pogorelov, Differential Geometry, 1974)

Then:

;K _n = K ₁ cos ² φ ₀ + K ₂ sin ² φ ₀ >0;

;

Here:

ρ _n is the radius of curvature of the tow on the mandrel;

φ ₀ - angle of winding of the torus;

;

- главные кривизны для тора.

;

are the main curvatures for the torus.

Given the expressions for K ₁ and K ₂ we get:

t cos ² φ ₀ + sin υ> 0.

The most critical case is when sin υ = -1; (υ = -90 °),

this case corresponds to R = R _min = R ₀ -r;

For the torus surface of the spoke in question:

R _min - unknown, known R _ext .

From Figure 10 it follows R _ext = R ₀ -r sinγ;

;

;

;

;

и sinγ≈1, тогда R_вн≈R_min.Since thin needle N≈30 mm, and R _ext ≈3000 mm, then

and sinγ≈1, then R _ext ≈R _min.

Thus, the restriction has the form:

.

.

Whence we obtain the required formula r <R _int · ctg ² φ ₀ .

In our case, at φ ₀ = 45 °, ctg45 ° = 1 and r <R _ext .

These distinctive features are significant, since each individually and all together are aimed at solving the problem with the achievement of a technical result. The use of a single set of essential distinguishing features in the known solutions was not found, which characterizes the conformity of the technical solution to the criterion of "novelty."

A single set of new essential features with common known provides a solution to the problem with the achievement of the technical result and characterizes the proposed technical solution with significant differences compared with the prior art and analogues. This technical solution is the result of research and experimental work to improve the manufacturability of the knitting needles of the mesh structure and the reliability of its operation without the use of well-known design solutions, recommendations, materials and is non-obvious, which indicates its compliance with the criterion of "inventive step".

The invention is illustrated by drawings, where in Fig.1 shows a General view of the method, Fig.2 is a section of the mandrel along the path of the winding, Fig.3 is the same for the prior art, Fig.4 is a section of the mandrel along the grooves, Fig .5 is a knitting needle, the left view, in Fig.6 is the trajectory of the winding of the bundles, in Fig.7 is a diagram for deriving the formula for step-by-step adjustment of the winding angle, in Fig.8, 9, 10 are diagrams for deriving the formula of the radius of the torus surface.

A method of manufacturing a curved needle 1 from composite materials, in which a dividing layer 3 of easily removable material is applied to a rigid curved mandrel 2, the profile of which is defined by the intersection of two lateral planes 4 and two curved, outer cylindrical 5 and inner torus 6, surfaces, at the intersections of all surfaces perform four grooves 7 for laying bundles 8 of the main longitudinal ribs 9 of the spoke 1, on the cylindrical 5 and torus 6 surfaces - grooves 7 for additional longitudinal ribs 10 and n all the surfaces - the spiral groove 7 in both directions for filament winding spiral fins 11 needles 1, wherein the spiral groove 7 on the curved, cylindrical 5 and torus 6, surfaces operate with software winding angle φ ₀ between the tangent 12 to the take-up coil wiring 8 and the tangent 13 to the forming 14 curved surface, on the lateral planes 4 when switching from plane 4 to curved surface 5 and 6, providing a winding angle between the wound cord 8 and normal 15 to the guide circle 16 of this curved surface - φ _0, and the transition from the curved surface 5 and 6 on the plane 4 - (φ ₀ + Δφ), ensuring equality φ ₀ for all mandrel surfaces, wherein Δφ is given by:

,

,

;

, где:

;

where:

x ₀ , y ₀ - coordinates of the center of the transition circle on the plane to which the wound edge 11 belongs;

x _n , y _n - the coordinates of the point on the plane from which the edge 11;

x _{n + 1} , y _{n + 1} - coordinates of the end of edge 11 in the plane.

The forming radius r of the torus 17 is determined by the formula:

r <R _int · ctg ² φ ₀ , where:

R _vn is the radius of the guide circle of the torus surface;

φ ₀ - the angle between the edge 11 and the tangent 13 to the generatrix of the circle 14 of the torus surface 6, see figure 4, 6.

Then, bundles 8 of unidirectional polymer fibers impregnated with a synthetic binder are wound in layers into the grooves 7 to provide winding parameters for obtaining a mesh structure of the spoke 1 and ensuring straightness of the segments of the longitudinal ribs 9 and 10 on the torus 6 of the inner surface of the spokes 1, the segments of the spiral ribs 11 on the side planes 4, the curvature of the longitudinal ribs 9 and 10 of the outer cylindrical surface 5 and the bulge 18 (see figure 2) of the segments of the spiral ribs 11 on the cylindrical 5 and torus 6 surfaces, after curing eniya binder needle 1 with a separating layer 3 is removed from the mandrel 2 and the spokes 1 of the separation layer 3 was removed.

The specified bending stiffness of the spokes 1 is experimentally selected by the method of symmetrical cutting sections of additional ribs 10.

The cross-sectional area of the main 9 longitudinal ribs is performed at least 4-5 times more than the spiral 11 and an additional 10 longitudinal.

Curved knitting needle 1 made of composite materials, the profile of which is defined by the intersection of two lateral planes 4 and two curved, outer cylindrical 5 and inner torus 6, surfaces, including bundles 8 made of unidirectional with the formation of a honeycomb structure, four main 9 longitudinal ribs impregnated with a synthetic binder located at the intersection of all surfaces, located on curved surfaces an additional 10 longitudinal ribs and located on all surfaces tyah spiral 11 edges in both directions, wherein the helical ribs 11 on the curved, cylindrical, 5 and torus 6, surfaces arranged at an angle φ ₀ between the tangent 12 to the edge and the tangent 13 to the generator 14 of the curved surface on the side plane 4 at the transition from the plane 4 curved surface 5 and 6 - at an angle between the edge and the normal 15 to the guide circle 16 of this curved surface - φ ₀ , and when passing from curved surface 5 and 6 to plane 4 - (φ ₀ + Δφ), ensuring equality φ ₀ for all surface needles 1, wherein Δφ is defined by the formula:

,

,

;

, где:

;

where:

x ₀ , y ₀ - coordinates of the center of the circle of transition to the plane to which the edge 11 belongs;

x _n , y _n - coordinates of the point of origin of the edge 11 in the plane;

x _{n + 1} , y _{n + 1} - coordinates of the end of edge 11 in the plane.

The generating radius r of the torus 17 is defined by the formula:

r <R _int · ctg ² φ ₀ , where:

R _vn is the radius of the guide circle of the torus surface;

φ ₀ - the angle between the edge 11 and the tangent 13 to the generatrix of the circle 14 of the torus surface 6, see figure 4, 6.

The specified bending stiffness of the spokes 1 is experimentally selected by the method of symmetric cutting of sections of the additional ribs 10, and the symmetry (relative to the longitudinal plane of symmetry of the spokes 1) of the sections cutting ensures that the console does not torsion during bending.

The cross-sectional area of the main longitudinal rib 9 is made at least 4-5 times larger than the spiral 11 and the additional longitudinal 10.

An example of a specific implementation of the method is that the spoke 1 is wound while providing winding parameters, including φ ₀ , Δφ, as well as the radius R of curvature 19 of the spoke 1 (see Fig. 5). Moreover, the curvature of the 19 knitting needles based on the technical requirements of the design documentation can be defined by more than one mating radii with the corresponding centers of the circles (x ₀ , y ₀ ). In this case, the parameters Δφ ₁ , Δφ ₂ , Δφ ₃ , etc. are also determined. for each winding section based on R ₁ , R ₂ , R ₃ , etc. and defined by the drawing for use in the presented formula, for example, the coordinates of the point (x _n , y _n ) (see Fig. 7) belonging to a curve, for example, of radius R ₁ (see Fig. 5), from which the bundle comes out at an angle to the normal (φ ₀ + Δφ) (see Fig.7). The coordinates of the point (x _{n + 1} , y _{n + 1} ) (see Fig. 7) are determined from the condition that the point of the curve has a radius of R ₃ (see Fig. 5) and the condition that the tow comes to this point at an angle φ ₀ = const ( see Fig. 7) to the normal to this curve. The bundles 8 are wound along a geodesic path except for the case of a transition from a curved surface 5, 6 to a lateral plane 4, that is, at the time of correction φ. In this case, in order to improve the quality of laying of the bundles 8 in the grooves 7 (so that the bundle was not held due to the recess in the groove, but as on a smooth mandrel), it is necessary to fulfill the condition | tgΔφ / 2 | <k _tr , where k _tr is the coefficient of friction during winding . If necessary, the fulfillment of this condition can be provided, for example, by adjusting the angle φ ₀ . In addition, to ensure a given bending stiffness of the spoke 1, it is loaded cantilever (see Fig. 5) with a unit force q, and to ensure that the measured deflection and its dispersion between the individual spokes meets the technical requirements, sections of symmetrical additional longitudinal ribs 10 are cut out on surface 5 or surface 6 , adjusting the decrease in stiffness to the desired value. Moreover, to ensure a given stiffness along the length of the knitting needle (coincidence of an elastic line 20 for several knitting needles of a set), the deflection is measured at several points of the knitting needles with a symmetrical notch of the ribs 10 in the corresponding sections.

The curved spoke 1 works as follows. When using a spoke as an element of the frame of a mirror reflector with a working surface formed by spraying a mirror material onto a sheet material (flexible film), increased demands are made on the matching of elastic lines 20 under the action of bending loads to each spoke 1 of the frame to eliminate distortion of the mirror. When changing the position of the mirror reflector (rotation, displacement), inertial loads act on the frame, which are reduced for each spoke 1 to the effect of bending force on it. Due to the proposed optimization of the bending stiffness of the spoke 1 along its length, the distortion of the mirror does not occur.

The use of inventions will allow you to create a high-tech design of a curved mesh needle of high quality and with increased reliability, which confirms the intended use. The feasibility of the inventions is confirmed by the positive test results of the prototypes and prototypes of the knitting needles, knots and prototypes of the reflector, the development and manufacture of which are fully based on the presented description. In this regard, the new technical solution also meets the criterion of "industrial applicability", i.e. level of invention.

Claims (6)

1. A method of manufacturing a curved needle from composite materials, in which a dividing layer of easily removable material is applied to a rigid curved mandrel, the profile of which is defined by the intersection of two lateral planes and two curved, outer cylindrical and inner torus surfaces, four grooves are made at the intersections of all surfaces for laying the bundles of the main longitudinal ribs of the knitting needles, on the cylindrical and torus surfaces - grooves for additional longitudinal ribs, and on all surfaces ostakh - spiral grooves in both directions for winding bundles of spiral ribs of a spoke, and the spiral grooves on curved, cylindrical and torus surfaces are performed to provide a winding angle φ ₀ between the tangent to the coiled coil and tangent to the generatrix of the curved surface, on the lateral planes when moving from the plane on the curved surface - with the software of the angle between wound winding wiring and the normal to the curved surface of the guide circle - φ _0, and the transition from a ivolineynoy surface plane - (φ ₀ + Δφ), ensuring equality φ ₀ for all mandrel surfaces, wherein Δφ is given by:

where x ₀ , y ₀ are the coordinates of the center of the transition circle on the plane to which the wound edge belongs;
x _n , y _n - coordinates of the point on the plane from which the edge comes out;
x _{n + 1} , y _{n + 1} - coordinates of the end of the edge in the plane,
wherein the generatrix of the torus radius r is determined by the formula:
r <R _int · ctg ² φ ₀ ,
where R _VN is the radius of the guide circle of the torus surface;
φ ₀ is the angle of winding between the wound tourniquet of the rib and the tangent to this generatrix of the circumference of the torus surface,
Then, bundles of unidirectional polymer fibers impregnated with a synthetic binder are wound in layers into the grooves to provide winding parameters for obtaining a mesh structure of the knitting needle and ensuring the straightness of the segments of the longitudinal ribs on the torus inner surface of the spoke, the segments of spiral ribs on the lateral planes, the curvature of the longitudinal ribs of the outer cylindrical surface and the convexity pieces of spiral ribs on a cylindrical and torus surfaces and, after curing the binder, a spoke with a section the integral layer is removed from the mandrel and the separation layer is removed from the spoke. 2. The method according to claim 1, characterized in that the specified bending stiffness of the spokes of the kit is experimentally selected by the method of symmetrical cutting of sections of additional ribs on each spoke during its testing. 3. The method according to claim 1, characterized in that the cross-sectional area of the main longitudinal ribs is performed at least 4-5 times more than the spiral and additional longitudinal. 4. A curved needle made of composite materials, the profile of which is defined by the intersection of two lateral planes and two curved, outer cylindrical and inner torus surfaces, including four main longitudinal ribs impregnated with a synthetic binder of polymer fibers made of unidirectional with the formation of a cellular structure polymeric fibers located at the intersection all surfaces located on curved surfaces additional longitudinal ribs and located on all surfaces of the joint oral ribs of both directions, and spiral ribs on curved, cylindrical and torus surfaces are located at an angle φ ₀ between the tangent to the rib and tangent to the generatrix of the curved surface, on the lateral planes when changing from a plane to a curved surface - at an angle between the rib and the normal to the guide circumference of the curved surface - φ _0, and the transition from the curved surface onto the plane - (φ ₀ + Δφ) with equality φ ₀ for all surfaces of the spokes, wherein Δφ is defined pho muloy:

where x ₀ , y ₀ are the coordinates of the center of the transition circle on the plane to which the edge belongs;
x _n , y _n - coordinates of the point of origin of the edge in the plane;
x _{n + 1} , y _{n + 1} - coordinates of the end of the edge in the plane,
wherein the generating radius of the torus r is defined by the formula:
r <R _int · ctg ² φ ₀ ,
where R _VN is the radius of the guide circle of the torus surface;
φ ₀ - the angle between the edge and the tangent to the generatrix of the circumference of the torus surface. 5. The spoke according to claim 4, characterized in that the specified bending stiffness of the spoke set is experimentally selected by the method of symmetric cutting sections of additional ribs on each spoke during its testing. 6. The spoke according to claim 4, characterized in that the cross-sectional area of the main longitudinal rib is made at least 4-5 times larger than the spiral and additional longitudinal.

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