Line drawing method for winding track of circular arc section framework of flexible right-angle elbow with small bending diameter ratio

Abstract

The invention discloses a small-bend-diameter-ratio flexible right-angle bent pipe arc section framework winding track line drawing method which comprises the following steps that a small-bend-diameter-ratio flexible right-angle bent pipe arc section framework winding track line drawing template is manufactured firstly, and then one side of the line drawing template is aligned with a central circle ring of an arc section to be subjected to circle closing and attaching; drawing a skeleton winding track line along the other side of the line drawing template, after a previous skeleton winding track line is drawn, moving and rotating the line drawing template to the joint of the head end or the tail end of the drawn skeleton winding track line, and drawing an adjacent skeleton winding track line; and repeating the steps so as to draw all skeleton winding tracks of the circular arc section of the small-bending-diameter-ratio flexible right-angle bent pipe. The drawing tool has the advantages that operation is convenient, the framework winding track of the arc section of the small-bending-diameter-ratio flexible right-angle bent pipe can be drawn easily, and the small-bending-diameter-ratio flexible right-angle bent pipe can be machined and manufactured conveniently.

Description

Technical Field

[0001] The invention relates to the technical field of flexible right-angle bend pipes with small bend-diameter ratio, and in particular to a method for drawing a winding trajectory of a circular arc segment skeleton of a flexible right-angle bend pipe with small bend-diameter ratio. Background Art

[0002] Flexible pipes play an important role in the transmission of media, flexible connection of pipelines, compensation of displacement of the system and connected equipment caused by vibration and impact, and reduction of structural noise transmission along the pipeline in modern ship piping systems.

[0003] Flexible right-angle elbow is a commonly used flexible pipe in the piping system, generally containing a 90° arc section and straight pipe sections on both sides, such as Figure 1 and Figure 2 As shown, the shape of the arc segment is a 1 / 4 annular ring, and the hollow diameter is the diameter DN of the entire elbow. The bend-diameter ratio of the flexible right-angle elbow is related to its flow effect and occupied space. The smaller the bend-diameter ratio, the smaller the occupied space. The bend-diameter ratio refers to the ratio of the ring radius R of the arc segment to the diameter DN of the entire elbow. Therefore, when the space of the pipeline system is limited, a flexible right-angle elbow with a small bend-diameter ratio is often required while ensuring the flow effect. When manufacturing flexible right-angle elbows, controlling the winding angle of the cord (i.e., the skeleton material) is the key technology for the flexible right-angle elbow to maintain balance under the action of the internal fluid pressure of the pipe.

[0004] At present, in the manufacturing process of flexible right-angle bend pipes, a special winding machine is generally used to complete the winding of the tube body skeleton material (i.e., cord) to achieve the balance requirements of the connecting pipe, but due to the structural limitations of the winding machine, the above method cannot process flexible right-angle bend pipes with small bend-diameter ratios. In order to achieve the balanced performance of the flexible right-angle bend pipe under the pressurized state, the skeleton must be designed to wind the straight pipe section and the arc section at a certain winding angle. At present, when winding the skeleton, it is generally necessary to first draw the winding trajectory line of the skeleton material on the surface of the inner rubber layer 01 of the flexible right-angle bend pipe, and then wind the skeleton material according to this winding trajectory line. This winding trajectory is a regular spiral curve in the straight pipe section of the flexible right-angle bend pipe, which is easy to determine and draw, but it is a complex spatial curve in the arc section and is not easy to determine. To this end, the present application provides a method for drawing the skeleton winding trajectory for the arc section of a flexible right-angle bend pipe with a small bend-diameter ratio. Summary of the invention

[0005] The purpose of the present invention is to provide a method for drawing the winding trajectory of the arc segment skeleton of a flexible right-angle bend pipe with a small bend-to-diameter ratio, so as to solve the technical problems existing in the background technology.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A method for drawing a winding trajectory of a circular arc segment skeleton of a flexible right-angle bend pipe with a small bend-to-diameter ratio, comprising the following steps:

[0008] S1, making a skeleton winding track drawing template for a small bend-to-diameter ratio flexible right-angle elbow circular arc segment, wherein the drawing template comprises a straight line edge, an arc edge and a curved line edge;

[0009] S2, aligning the straight edge of the line drawing template with the center circle of the small bending ratio flexible right angle elbow pipe arc segment and pasting the ring circle on the inner rubber layer surface of the small bending ratio flexible right angle elbow pipe arc segment;

[0010] S3, drawing a skeleton winding trajectory line of the small bending ratio flexible right angle bend pipe circular arc section on the surface of the inner rubber layer of the small bending ratio flexible right angle bend pipe circular arc section along the curved edge of the line drawing template;

[0011] S4, after the last skeleton winding trajectory line is drawn, the drawing template is moved along the axial direction of the small bending ratio flexible right angle bend pipe arc segment and rotated to the position where the drawing skeleton winding trajectory line is connected with the head end or tail end of the drawn skeleton winding trajectory line, and then a skeleton winding trajectory line adjacent to the drawn skeleton winding trajectory line is drawn on the inner rubber layer surface of the small bending ratio flexible right angle bend pipe arc segment along the curved edge of the drawing template;

[0012] S5, repeat step S4 until all the skeleton winding trajectory lines of the small bending ratio flexible right angle bend pipe circular arc section are drawn on the inner rubber layer surface of the small bending ratio flexible right angle bend pipe circular arc section, and the drawing of all the skeleton winding trajectory lines of the small bending ratio flexible right angle bend pipe circular arc section is completed.

[0013] Further, in step S1, the steps of making the line drawing template are as follows:

[0014] S11. Draw a plane contour diagram of a circular arc segment of a flexible right-angle elbow with a small bending-diameter ratio in a professional drawing software, wherein the plane contour diagram of the circular arc segment is a circular ring segment, and the circular ring segment is composed of two upper and lower arc edges and two left and right straight edges;

[0015] When the arc segment plane contour diagram is drawn in the drawing software, the straight edge on the right is drawn in a vertical state, and the upper arc edge is represented by an arc solid line segment aA, the lower arc edge is represented by an arc solid line segment Bb, the left straight edge is represented by a dotted straight line segment aB, and the right straight edge is represented by a dotted straight line segment Ab;

[0016] The left and right endpoints of the arc solid line segment aA are represented by point a and point A respectively, the left and right endpoints of the arc solid line segment Bb are represented by point B and point b respectively, the upper and lower endpoints of the imaginary straight line aB are represented by point a and point B respectively, and the upper and lower endpoints of the imaginary straight line Ab are represented by point A and point b respectively;

[0017] S12, drawing a plane projection of the skeleton winding trajectory line of the small bending-diameter ratio flexible right-angle elbow circular arc segment on the circular arc segment plane contour diagram, the plane projection of the skeleton winding trajectory line is a curve connecting the right end point of the arc solid line end aA and the left end point of the arc solid line Bb, recorded as curve AB;

[0018] S13, determining the center point of the circular ring of the small bending-diameter ratio flexible right-angle elbow circular arc segment on the circular arc segment plane contour diagram, and recording it as O, wherein the determined circular ring center point O is located on the extension line of the virtual straight line segment Ab;

[0019] S14, draw a semicircle with the same diameter as the ring circle of the small bending ratio flexible right angle elbow arc segment on the right side of the arc segment plane contour diagram, and align the semicircle with the virtual straight line segment Ab;

[0020] S15, divide the semicircle into N equal parts to obtain N+1 equal parts, and then draw horizontal lines from the N+1 equal parts to the imaginary straight line segment Ab in sequence, and then draw horizontal lines with the center point of the circular arc segment of the flexible right-angle elbow with small bending diameter ratio as the center of the circle, R i Draw an arc with radius C i , draw N+1 arcs C i ; Among them, R i The distance from the intersection of the horizontal line drawn from the equally divided point i and the imaginary straight line segment Ab to the center point O of the circular arc segment of the flexible right-angle elbow with a small bending diameter ratio, N is an integer ≥ 1;

[0021] S16, draw a straight line H with a length equal to the circumference of the semicircle next to the arc segment plane contour diagram, and divide the straight line H into N segments according to the equal fractions of the semicircle to obtain N+1 equal division points, and then sequentially divide the N+1 arcs C drawn in step S15 into i Copy it to the N+1 equally divided points of the straight line H, and then copy the N+1 arcs C i The end far from the straight line H is connected with a smooth curve to obtain a curve, which is recorded as curve A'B';

[0022] S17, printing out the figure including the straight line H, N+1 arcs Ci and the curve A'B' drawn in step S16, and then cutting out the printed figure along the outer contours of the straight line H and the curve A'B' to obtain the line drawing template.

[0023] Further, in step S12, the step of drawing a plane projection of the winding trajectory line of the small bending ratio flexible right angle bend pipe arc segment skeleton on the arc segment plane contour diagram is as follows:

[0024] S111. Draw a cylinder whose pitch circle radius is the same as the pitch circle radius of the small bending diameter ratio flexible right angle bend pipe arc segment and whose length is the same as the small bending diameter ratio flexible right angle bend pipe arc segment, and is recorded as cylinder a. 1 ;

[0025] S112, with cylinder a 1 With the left end face of the pipe as the center, draw a torus with the same radius as the circular segment of the small bending ratio flexible right angle elbow, denoted as torus a 2 ;

[0026] S113, according to the designed skeleton winding angle α, first on the cylinder a 1 Make a spiral trajectory m on the cylindrical surface 1 , and then calculate the spiral trajectory m 1 Mapping to the torus a 2 The coordinate values ​​of a series of points on the torus surface are connected in sequence to obtain the spiral trajectory line m 1 Mapping to the torus a 2 The spiral trajectory m on the torus 2 , the spiral trajectory m 2 That is the skeleton winding trajectory line of the required small bending-diameter ratio flexible right-angle elbow circular arc section;

[0027] S114, using the spiral trajectory m calculated in step S113 2 The coordinate value of the plane diagram of the trajectory line is drawn on the 1 / 2 arc segment plane contour diagram, and the plane projection of the winding trajectory line of the small bending diameter ratio flexible right angle elbow arc segment skeleton can be obtained.

[0028] Further, in step S113, the spiral trajectory m is calculated 1 Mapping to the torus a 2 The coordinate values ​​of a series of points on the torus surface are used to obtain the spiral trajectory m 2 The method is as follows:

[0029] (1) With cylinder a 1 The center of the left end face is the coordinate origin O, the vertical direction is the X coordinate axis, the horizontal direction is the Y coordinate axis, and the axis along the cylinder is the Z coordinate axis, establishing a three-dimensional rectangular coordinate system;

[0030] (2) Determine the spiral trajectory m 1 Any point A 2 The corresponding coordinate values ​​in the three-dimensional rectangular coordinate system in (1);

[0031] Among them, for the spiral trajectory m 1 Any point A on 1 , which corresponds to the spiral trajectory m1 With cylinder a 1 The pitch circle C of a cylindrical surface 1 If the intersection point is recorded on the corresponding cylindrical surface pitch circle C 1 The angle of rotation is θ, and its corresponding coordinate values ​​in the three-dimensional rectangular coordinate system in (1) are as follows:

[0032] x 1 =r×cosθ

[0033] y 1 =r×sinθ

[0034]

[0035] Among them, x 1 ,y 1 , z 1 Point A 1 In (1), the coordinate value in the three-dimensional rectangular coordinate system; r is the cylinder a 1 Pitch circle C of a cylindrical surface 1 The radius of

[0036] (3) Determine point A 1 Mapping to the torus a 2 Point A on 2 , and find point A 1 Map to point A 2 The coordinate value of

[0037] Among them, for the spiral trajectory m 1 Any point A on 1 , in the torus a 2 There are corresponding mapping points A on the torus surface 2 , and this mapping point A 2 At the same time, the spiral trajectory m 2 The point on;

[0038] Among them, due to point A 1 On the cylindrical surface pitch circle C 1 When the cylinder a 1 Mapping to the torus a 2 When , there is a cylindrical pitch circle C 1 Corresponding mapping to torus a 2 The pitch circle of the torus surface C 2 , and the pitch circle C of the torus 2 The center point O 2 The length of the arc from the origin O of the three-dimensional rectangular coordinate system in (1) is equal to the pitch circle C of the cylindrical surface. 1 The center point O 1 The distance to the origin O of the three-dimensional rectangular coordinate system in (1), and the torus a2 Surface pitch circle C 2 The plane passes through the torus a 2 The axis of

[0039] Among them, due to point A 2 Point A 1 The mapping point of point A 2 On the torus pitch circle C 2 The angle of rotation and point A 1 On the cylindrical surface pitch circle C 1 The angle of rotation is the same;

[0040] Among them, in finding point A 1 Map to point A 2 When the coordinate value of the torus a is 2 The center of the bottom of the ring O 3 is the origin, the radial distance is ρ, the azimuth is β, and the height is h. Find point A 2 The coordinate value in this cylindrical coordinate system; then point A 2 The coordinate values ​​in the cylindrical coordinate system are transformed back to the three-dimensional rectangular coordinate system in (1) to find point A. 1 Map to point A 2 The coordinate value of

[0041] Among them, the point A 2 The coordinate values ​​in the cylindrical coordinate system are as follows:

[0042] ρ 2 =R+x 1

[0043] β 2 =z 1 / R

[0044] h 2 =y 1

[0045] Among them, ρ 2 ,β 2 ,h 2 Point A 2 Coordinate values ​​in the cylindrical coordinate system; R is the torus a 2 The radius of the circle;

[0046] Among them, the point A 1 Map to point A 2 The coordinate values ​​are as follows:

[0047] x 2 =ρ 2 ×cosβ 2 -R=(R+x 1)×cosβ 2 -R

[0048] y 2 =h 2 =y 1

[0049] z 2 =ρ 2 ×cosβ 2 =(R+x 1 )×sinβ 2

[0050] Among them, x 2 ,y 2 , z 2 Point A 2 In (1), the coordinate value in the three-dimensional rectangular coordinate system; R is the torus a 2 The radius of the circle;

[0051] (4) Follow the above steps (3) to find the spiral trajectory m 1 Mapping to the torus a 2 The coordinate values ​​of all points on the torus surface are then connected with lines to obtain the spiral trajectory m. 2 .

[0052] Compared with the prior art, the advantages of the present invention are as follows: simple operation, and the skeleton winding trajectory of the arc section of the flexible right-angle bend pipe with a small bend ratio can be easily drawn, which is convenient for the processing and manufacturing of the flexible right-angle bend pipe with a small bend ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solution in this embodiment, the following is a brief introduction to the drawings required for use in the description of the embodiment. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0054] Figure 1 It is a structural schematic diagram of a flexible right-angle elbow with a small bend-diameter ratio;

[0055] Figure 2 It is a cross-sectional view of a flexible right-angle elbow with a small bend-to-diameter ratio;

[0056] Figure 3 This is a diagram showing an embodiment of a drawing template used in a drawing method for drawing a track of a circular arc segment skeleton of a flexible right-angle bend pipe with a small bend-diameter ratio according to the present invention;

[0057] Figure 4 It is a planar schematic diagram of a skeleton winding trajectory drawn on a circular arc section of a flexible right-angle elbow with a small bending-diameter ratio using a line drawing template;

[0058] Figure 5 It is a planar schematic diagram of a series of skeleton winding trajectories drawn on the arc section of a flexible right-angle elbow with a small bending-diameter ratio using a line drawing template;

[0059] Figure 6 It is the plane contour diagram of the arc section of the flexible right-angle elbow with a small bend-to-diameter ratio;

[0060] Figure 7 It is a plane contour diagram of a circular arc section of a flexible right-angle elbow with a small bending-diameter ratio;

[0061] Figure 8 It is a schematic diagram of a plane projection of a skeleton winding trajectory line drawn on a plane contour diagram of a circular arc section of a flexible right-angle elbow with a small bending diameter ratio;

[0062] Figures 9 to 12 It is a schematic diagram of the production process of the line drawing template;

[0063] Figure 13-14 Schematic diagram of the mapping principle between the cylinder and the torus. DETAILED DESCRIPTION

[0064] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the following further describes how the present invention is implemented in conjunction with the accompanying drawings and specific implementation methods.

[0065] The present invention provides a method for drawing a winding trajectory of a small bend-to-diameter ratio flexible right-angle bend pipe arc segment skeleton, comprising the following steps:

[0066] S1. Make a skeleton winding track drawing template for making a small bending ratio flexible right angle elbow circular arc segment. The drawing template includes a straight line edge, an arc edge and a curved line edge. Figure 3 As shown;

[0067] S2, align the straight edge of the line drawing template with the center circle of the small bending ratio flexible right angle elbow arc segment and stick the ring circle on the inner rubber layer surface of the small bending ratio flexible right angle elbow arc segment;

[0068] S3. Draw the skeleton winding trajectory line of the small bending ratio flexible right angle elbow circular arc section on the inner rubber surface of the small bending ratio flexible right angle elbow circular arc section along the curved edge of the drawing template. Figure 4 As shown;

[0069] S4, after the previous skeleton winding trajectory line is drawn, the drawing template is moved along the axial direction of the small bending ratio flexible right angle elbow pipe arc segment and rotated to the position where the skeleton winding trajectory line that has been drawn is connected with the head end or tail end, and then the skeleton winding trajectory line that is adjacent to the skeleton winding trajectory line that has been drawn is drawn on the inner rubber layer surface of the small bending ratio flexible right angle elbow pipe arc segment along the curved edge of the drawing template;

[0070] S5, repeat step S4 until all skeleton winding trajectory lines of the small bending ratio flexible right angle bend pipe arc segment are drawn on the inner rubber layer surface of the small bending ratio flexible right angle bend pipe arc segment, and the drawing of all skeleton winding trajectory lines of the small bending ratio flexible right angle bend pipe arc segment is completed. Figure 5 shown.

[0071] Specifically, in step S1, the steps of making the line drawing template are as follows:

[0072] S11. In professional drawing software (for example, AutoCAD drawing software), draw a plane contour diagram of a circular arc segment of a flexible right-angle elbow with a small bending-diameter ratio. The plane contour diagram of the circular arc segment is a circular ring segment, which is composed of upper and lower arc edges and left and right straight edges;

[0073] When drawing the plane contour of an arc segment in a drawing software, refer to Figure 7 As shown, the straight side on the right is drawn in a vertical state, and the upper arc side is represented by an arc solid line segment aA, the lower arc side is represented by an arc solid line segment Bb, the left straight side is represented by a dotted straight line segment aB, and the right straight side is represented by a dotted straight line segment Ab;

[0074] Among them, the left and right endpoints of the arc solid line segment aA are represented by point a and point A respectively, and point A is the outer arc point on the right vertical side, point a is determined by the radius of the ring passing through point B, the left and right endpoints of the arc solid line segment Bb are represented by point B and point b respectively, and point B is the plane projection of the small bending diameter ratio flexible right angle elbow arc segment skeleton winding trajectory line on the inner circle of the arc segment plane contour diagram, the upper and lower endpoints of the virtual straight line aB are represented by point a and point B respectively, and the upper and lower endpoints of the virtual straight line Ab are represented by point A and point b respectively;

[0075] S12. Draw the plane projection of the skeleton winding trajectory line of the small bending diameter ratio flexible right angle elbow arc segment on the arc segment plane contour diagram. The plane projection of the skeleton winding trajectory line is a curve connecting the right end point of the arc solid line end aA and the left end point of the arc solid line Bb, recorded as curve AB, refer to Figure 8 As shown;

[0076] Among them, point A and point B are the two end points of the plane projection of the arc segment skeleton winding trajectory line of the small bending diameter ratio flexible right angle elbow pipe, point a is the outer point on the same radius line of the circle as point B, and point b is the inner point on the same radius line of the circle as point A;

[0077] S13, determine the center point of the circular ring of the small bending diameter ratio flexible right angle elbow circular arc segment on the circular arc segment plane contour diagram, and record it as O. The determined circular ring center point 0 is located on the extension line of the virtual straight line segment Ab, refer to Fig. 9 As shown;

[0078] S14. Draw a semicircle on the right side of the arc segment plane outline drawing, which has the same diameter as the ring circle of the arc segment of the flexible right-angle elbow with a small bending diameter ratio, and align the semicircle with the virtual straight line segment Ab;

[0079] S15. Divide the semicircle into N equal parts to obtain N+1 equal parts, and then draw horizontal lines from these N+1 equal parts to the imaginary straight line segment Ab in sequence, and then draw horizontal lines with the center point of the circular arc segment of the flexible right-angle elbow with a small bending diameter ratio as the center of the circle, R i Draw an arc with radius C i , draw N+1 arcs C i , see Fig.10 As shown; where R i The distance from the intersection of the horizontal line drawn from the equally divided point i and the imaginary straight line segment Ab to the center point O of the circular arc segment of the flexible right-angle elbow with a small bending diameter ratio, N is an integer ≥ 1;

[0080] S16, draw a straight line H with a length equal to the circumference of the semicircle next to the arc segment plane contour, and divide the straight line H into N segments according to the equal fractions of the semicircle to obtain N+1 equal division points, and then sequentially divide the N+1 arcs C drawn in step S15 into i Copy it to the N+1 equally divided points of the straight line H, and then copy the N+1 arcs C i The end away from the straight line H is connected with a smooth curve to obtain a curve, which is called curve A'B'. Fig.11 As shown;

[0081] S17, print out the figure including the straight line H, N+1 arcs Ci and the curve A'B' drawn in step S16, and then cut the printed figure along the outer contour of the straight line H and the curve A'B' to obtain the line drawing template, see Fig.12 shown.

[0082] Specifically, in step S12, the steps of drawing the plane projection of the winding trajectory line of the small bending diameter ratio flexible right angle elbow circular arc segment skeleton on the circular arc segment plane contour diagram are as follows:

[0083] S111. Draw a cylinder whose pitch circle radius is the same as the pitch circle radius of the small bending diameter ratio flexible right angle bend pipe arc segment and whose length is the same as the small bending diameter ratio flexible right angle bend pipe arc segment, and is recorded as cylinder a. 1 ;

[0084] S112, with cylinder a 1 With the left end face of the pipe as the center, draw a torus with the same radius as the circular segment of the small bending ratio flexible right angle elbow, denoted as torus a 2 , see Fig.13 ;

[0085] S113, according to the designed skeleton winding angle α, first on the cylinder a 1 Make a spiral trajectory m on the cylindrical surface 1 , and then calculate the spiral trajectory m 1 Mapping to the torus a 2 The coordinate values ​​of a series of points on the torus surface are then connected in sequence to obtain the spiral trajectory line m 1 Mapping to the torus a 2 A spiral trajectory line m on the torus 2 , see Fig.14 , the spiral trajectory m 2 That is the skeleton winding trajectory line of the required small bending-diameter ratio flexible right-angle elbow circular arc section;

[0086] S114, using the spiral trajectory m calculated in step S113 2 The coordinate value of the arc segment is used to draw the plane diagram of its trajectory line on the plane contour diagram of the arc segment, and the plane projection of the skeleton winding trajectory line of the small bending diameter ratio flexible right-angle elbow arc segment can be obtained.

[0087] Specifically, in step S113, the spiral trajectory m is calculated. 1 Mapping to the torus a 2 The coordinate values ​​of a series of points on the torus surface are used to obtain the spiral trajectory m 2 The method is as follows:

[0088] (1) With cylinder a 1 The center of the left end face is the coordinate origin O, the vertical direction is the X coordinate axis, the horizontal direction is the Y coordinate axis, and the axis of the cylinder is the Z coordinate axis. A three-dimensional rectangular coordinate system is established. Fig.13 ;

[0089] (2) Determine the spiral trajectory m 1 Any point A 2 The corresponding coordinate values ​​in the three-dimensional rectangular coordinate system in (1);

[0090] Among them, for the spiral trajectory m1 Any point A on 1 , which corresponds to the spiral trajectory m 1 With cylinder a 1 The pitch circle C of a cylindrical surface 1 If the intersection point is recorded on the corresponding cylindrical surface pitch circle C 1 The angle of rotation is θ, and its corresponding coordinate values ​​in the three-dimensional rectangular coordinate system in (1) are as follows:

[0091] x 1 =r×cosθ

[0092] y 1 =r×sinθ

[0093]

[0094] Among them, x 1 ,y 1 , z 1 Point A 1 In (1), the coordinate value in the three-dimensional rectangular coordinate system; r is the cylinder a 1 Pitch circle C of a cylindrical surface 1 The radius of

[0095] (3) Determine point A 1 Mapping to the torus a 2 Point A on 2 , and find point A 1 Map to point A 2 The coordinate value of

[0096] Among them, for the spiral trajectory m 1 Any point A on 1 , in the torus a 2 There are corresponding mapping points A on the torus surface 2 , and this mapping point A 2 At the same time, the spiral trajectory m 2 Points on, see Fig.14 ;

[0097] Among them, due to point A 1 On the cylindrical surface pitch circle C 1 When the cylinder a 1 Mapping to the torus a 2 When , there is a cylindrical pitch circle C 1 Corresponding mapping to torus a 2 The pitch circle of the torus surface C 2 , and the pitch circle C of the torus 2 The center point O 2 The length of the arc from the origin O of the three-dimensional rectangular coordinate system in (1) is equal to the pitch circle C of the cylindrical surface.1 The center point O 1 The distance to the origin O of the three-dimensional rectangular coordinate system in (1), and the torus a 2 The pitch circle of the torus surface C 2 The plane passes through the torus a 2 The axis of

[0098] Among them, due to point A 2 Point A 1 The mapping point of point A 2 On the torus pitch circle C 2 The angle of rotation and point A 1 On the cylindrical surface pitch circle C 1 The angle of rotation is the same;

[0099] Among them, in finding point A 1 Map to point A 2 When you need to find the coordinate values ​​of a cylindrical coordinate system, first create a cylindrical coordinate system. Fig.13 , with a torus 2 The center of the bottom of the ring O 3 is the origin, the radial distance is ρ, the azimuth is β, and the height is h. Find point A 2 The coordinate value in this cylindrical coordinate system; then point A 2 The coordinate values ​​in the cylindrical coordinate system are transformed back to the three-dimensional rectangular coordinate system in (1) to find point A. 1 Map to point A 2 The coordinate value of

[0100] Among them, the point A 2 The coordinate values ​​in the cylindrical coordinate system are as follows:

[0101] ρ 2 =R+x 1

[0102] β 2 =z 1 / R

[0103] h 2 =y 1

[0104] Among them, ρ 2 ,β 2 ,h 2 Point A 2 Coordinate values ​​in the cylindrical coordinate system; R is the torus a 2 The radius of the circle;

[0105] Among them, the point A 1 Map to point A 2 The coordinate values ​​are as follows:

[0106] x 2 =ρ 2 ×cosβ 2 -R=(R+x 1 )×cosβ 2 -R

[0107] y 2 =h 2 =y 1

[0108] z 2 =ρ 2 ×cosβ 2 =(R+x 1 )×sinβ 2

[0109] Among them, x 2 ,y 2 , z 2 Point A 2 In (1), the coordinate value in the three-dimensional rectangular coordinate system; R is the torus a 2 The radius of the circle;

[0110] (4) Follow the above steps (3) to find the spiral trajectory m 1 Mapping to the torus a 2 The coordinate values ​​of all points on the torus surface are then connected with lines to obtain the spiral trajectory m. 2 .

[0111] Specifically, as an embodiment of the present invention: the semicircle in the above step S15 is divided into 18 equal parts, and 19 equal parts are obtained, that is, N=18; 19 horizontal lines can be drawn from these 19 equal parts to the virtual straight line segment Ab, and the 19 horizontal lines have 19 intersections with the virtual straight line segment Ab; with the center point of the circular ring of the small bending ratio flexible right-angle bend pipe arc segment as the center of the circle and the distance from the 19 intersections to the center point of the circular ring as the radius, 19 arcs can be drawn.

[0112] Figure 1 and Figure 2 What is shown is a schematic diagram of the structure of a flexible right-angle elbow with a small bending-diameter ratio;

[0113] Figure 3 What is shown is a schematic diagram of a drawing template used in the method for drawing a winding track of a circular arc segment skeleton of a flexible right-angle bend pipe with a small bend-diameter ratio according to the present invention;

[0114] Figure 4 The figure shows a plan view of a skeleton winding track drawn on a circular arc section of a flexible right-angle elbow with a small bending-diameter ratio using a line drawing template;

[0115] Figure 5 What is shown is a plan schematic diagram of all skeleton winding tracks drawn on a small bending-diameter ratio flexible right-angle elbow circular arc segment using a line drawing template;

[0116] Figure 6 What is shown is the plane profile of the arc section of the flexible right-angle elbow with a small bending-diameter ratio;

[0117] Figure 7 The figure shows a plane profile of a circular arc section of a flexible right-angle elbow with a small bending-diameter ratio;

[0118] Figure 8 The figure shows a schematic diagram of a plane projection of a skeleton winding trajectory line drawn on a plane contour diagram of a circular arc section of a flexible right-angle elbow with a small bending-diameter ratio;

[0119] Figures 9 to 12 Shown is a process diagram for making a line drawing template;

[0120] Fig.13 and Fig.14 The cylinder a is shown 1 With torus a 2 Schematic diagram of the mapping principle between them.

[0121] in, Figure 4 and Figure 5 The red curve in the middle represents the skeleton winding trajectory; Fig.14 Middle C 1 Represents a cylinder 1 A cylindrical surface pitch circle on the spiral trajectory m 1 Connected to A 1 ; C 2 Represents C 1 Mapped on torus a 2 The pitch circle of the torus on the 3 Represents a torus 2 The center circle of the ring; C 1 and C 2 The radius of C is r. 3 The radius is R.

[0122] Finally, it should be noted that the above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for drawing a winding track for a circular arc segment skeleton of a flexible right-angle bend pipe with a small bend-diameter ratio, characterized in that: The following steps are included: S1, making a skeleton winding track drawing template for a small bend-to-diameter ratio flexible right-angle elbow circular arc segment, wherein the drawing template comprises a straight line edge, an arc edge and a curved line edge; S2, aligning the straight edge of the line drawing template with the center circle of the small bending ratio flexible right angle elbow pipe arc segment and pasting the ring circle on the inner rubber layer surface of the small bending ratio flexible right angle elbow pipe arc segment; S3, drawing a skeleton winding trajectory line of the small bending ratio flexible right angle bend pipe circular arc section on the surface of the inner rubber layer of the small bending ratio flexible right angle bend pipe circular arc section along the curved edge of the line drawing template; S4, after the last skeleton winding trajectory line is drawn, the drawing template is moved along the axial direction of the small bending ratio flexible right angle bend pipe arc segment and rotated to the position where the drawing skeleton winding trajectory line is connected with the head end or tail end of the drawn skeleton winding trajectory line, and then a skeleton winding trajectory line adjacent to the drawn skeleton winding trajectory line is drawn on the inner rubber layer surface of the small bending ratio flexible right angle bend pipe arc segment along the curved edge of the drawing template; S5, repeat step S4 until all the skeleton winding trajectory lines of the small bending ratio flexible right angle bend pipe circular arc section are drawn on the inner rubber layer surface of the small bending ratio flexible right angle bend pipe circular arc section, and the drawing of all the skeleton winding trajectory lines of the small bending ratio flexible right angle bend pipe circular arc section is completed.

2. The method for drawing the trajectory line of the arc segment skeleton winding of a flexible right-angle bend pipe with a small bend-diameter ratio according to claim 1 is characterized in that: In step S1, the steps of making the line drawing template are as follows: S11. Draw a plane contour diagram of a circular arc segment of a flexible right-angle elbow with a small bending-diameter ratio in a professional drawing software, wherein the plane contour diagram of the circular arc segment is a circular ring segment, and the circular ring segment is composed of two upper and lower arc edges and two left and right straight edges; When the arc segment plane contour diagram is drawn in the drawing software, the straight edge on the right is drawn in a vertical state, and the upper arc edge is represented by an arc solid line segment aA, the lower arc edge is represented by an arc solid line segment Bb, the left straight edge is represented by a dotted straight line segment aB, and the right straight edge is represented by a dotted straight line segment Ab; The left and right endpoints of the arc solid line segment aA are represented by point a and point A respectively, the left and right endpoints of the arc solid line segment Bb are represented by point B and point b respectively, the upper and lower endpoints of the imaginary straight line aB are represented by point a and point B respectively, and the upper and lower endpoints of the imaginary straight line Ab are represented by point A and point b respectively; S12, drawing a plane projection of the skeleton winding trajectory line of the small bending-diameter ratio flexible right-angle elbow circular arc segment on the circular arc segment plane contour diagram, the plane projection of the skeleton winding trajectory line is a curve connecting the right end point of the arc solid line end aA and the left end point of the arc solid line Bb, recorded as curve AB; S13, determining the center point of the circular ring of the small bending-diameter ratio flexible right-angle elbow circular arc segment on the circular arc segment plane contour diagram, and recording it as O, wherein the determined circular ring center point O is located on the extension line of the virtual straight line segment Ab; S14, draw a semicircle with the same diameter as the ring circle of the small bending ratio flexible right angle elbow arc segment on the right side of the arc segment plane contour diagram, and align the semicircle with the virtual straight line segment Ab; S15, divide the semicircle into N equal parts to obtain N+1 equal parts, and then draw horizontal lines from the N+1 equal parts to the imaginary straight line segment Ab in sequence, and then draw horizontal lines with the center point of the circular arc segment of the flexible right-angle elbow with small bending diameter ratio as the center of the circle, R i Draw an arc with radius C i , draw N+1 arcs C i ; Among them, R i The distance from the intersection of the horizontal line drawn from the equally divided point i and the imaginary straight line segment Ab to the center point O of the circular arc segment of the flexible right-angle elbow with a small bending ratio, N is an integer ≥ 1; S16, draw a straight line H with a length equal to the circumference of the semicircle next to the arc segment plane contour diagram, and divide the straight line H into N segments according to the equal fractions of the semicircle to obtain N+1 equal division points, and then sequentially divide the N+1 arcs C drawn in step S15 into i Copy it to the N+1 equally divided points of the straight line H, and then copy the N+1 arcs C i The end far from the straight line H is connected with a smooth curve to obtain a curve, which is recorded as curve A'B'; S17, printing out the figure including the straight line H, N+1 arcs Ci and the curve A'B' drawn in step S16, and then cutting out the printed figure along the outer contours of the straight line H and the curve A'B' to obtain the line drawing template.

3. The method for drawing the trajectory line of the arc segment skeleton winding of a flexible right-angle bend pipe with a small bend-diameter ratio according to claim 2 is characterized in that: In step S12, the steps of drawing the plane projection of the winding trajectory line of the small bending ratio flexible right angle elbow circular arc segment skeleton on the circular arc segment plane contour diagram are as follows: S111, draw a cylinder whose cylindrical pitch circle radius is the same as the circular segment circle radius of the small bending diameter ratio flexible right angle bend pipe arc segment and whose length is the same as the small bending diameter ratio flexible right angle bend pipe arc segment, recorded as cylinder a1; S112, taking the left end face of the cylinder a1 as the center, draw a torus with the same radius as the circular segment of the small bending ratio flexible right angle elbow arc segment, recorded as torus a2; S113, according to the designed skeleton winding angle α, first make a spiral trajectory line m1 on the cylindrical surface of the cylinder a1, then calculate the coordinate values ​​of a series of points on the torus surface of the torus a2 mapped from the spiral trajectory line m1, and connect these calculated series of points in sequence to obtain a spiral trajectory line m2 on the torus surface of the torus a2 mapped from the spiral trajectory line m1, and the spiral trajectory line m2 is the skeleton winding trajectory line of the required small bend-to-diameter ratio flexible right-angle elbow circular arc segment; S114. Use the coordinate values ​​of the spiral trajectory line m2 calculated in step S113 to draw a plane diagram of its trajectory line on the 1 / 2 arc segment plane contour diagram, so as to obtain the plane projection of the small bend-diameter ratio flexible right-angle bend pipe arc segment skeleton winding trajectory line.

4. The method for drawing the winding trajectory line of the arc segment skeleton of a flexible right-angle bend pipe with a small bend-diameter ratio according to claim 3 is characterized in that: In step S113, the coordinate values ​​of a series of points on the torus surface of the torus a2 mapped to the spiral trajectory m1 are calculated, and the method for obtaining the spiral trajectory m2 is as follows: (1) Establish a three-dimensional rectangular coordinate system with the center of the left end face of the cylinder a1 as the coordinate origin O, the vertical direction as the X coordinate axis, the horizontal direction as the Y coordinate axis, and the Z coordinate axis along the axial direction of the cylinder; (2) Determine the coordinate value of any point A2 on the spiral trajectory m1 in the three-dimensional rectangular coordinate system in (1); Among them, for any point A1 on the spiral trajectory m1, it corresponds to the intersection of the spiral trajectory m1 and a cylindrical surface pitch circle C1 of the cylinder a1. If the angle it rotates in the corresponding cylindrical surface pitch circle C1 is θ, then its corresponding coordinate value in the three-dimensional space rectangular coordinate system in (1) is as follows: x1=r×cosθ y1=r×sinθ Where x1, y1, z1 are the coordinates of point A1 in the three-dimensional rectangular coordinate system in (1); r is the radius of the pitch circle C1 of a cylindrical surface on the cylinder a1; (3) Determine the mapping of point A1 to point A2 on the torus a2, and calculate the coordinate value of the mapping of point A1 to point A2; Among them, for any point A1 on the spiral trajectory line m1, there is a corresponding mapping point A2 on the annular surface of the annular body a2, and this mapping point A2 is also a point on the spiral trajectory line m2; Among them, since point A1 is on the cylindrical pitch circle C1, when the cylinder a1 is mapped to the torus a2, the cylindrical pitch circle C1 is mapped to the torus pitch circle C2 on the surface of the torus a2, and the arc length from the center point O2 of the torus pitch circle C2 to the origin O of the three-dimensional rectangular coordinate system in (1) is equal to the distance from the center point O1 of the cylindrical pitch circle C1 to the origin O of the three-dimensional rectangular coordinate system in (1), and the plane where the torus pitch circle C2 on the surface of the torus a2 is located passes through the axis of the torus a2; Among them, since point A2 is the mapping point of point A1, the angle that point A2 rotates in the torus pitch circle C2 is the same as the angle that point A1 rotates in the cylindrical pitch circle C1; When calculating the coordinate value of point A1 mapped to point A2, a cylindrical coordinate system is first established, with the bottom center O3 of the ring where the torus a2 is located as the origin, the radial distance is denoted as ρ, the azimuth is denoted as β, and the height is denoted as h, and the coordinate value of point A2 in this cylindrical coordinate system is calculated; then the coordinate value of point A2 in the cylindrical coordinate system is transformed back to the three-dimensional rectangular coordinate system in (1), and the coordinate value of point A1 mapped to point A2 can be calculated; Among them, the coordinate values ​​of point A2 in the cylindrical coordinate system are as follows: ρ2=R+x1 β2=z1 / R h2=y1 Among them, ρ2, β2, h2 are the coordinate values ​​of point A2 in the cylindrical coordinate system; R is the radius of the ring where the torus a2 is located; Among them, the coordinate values ​​of point A1 mapped to point A2 are as follows: x2=ρ2×cosβ2-R=(R+x1)×cosβ2-R y2=h2=y1 z2=ρ2×cosβ2=(R+x1)×sinβ2 Where x2, y2, z2 are the coordinates of point A2 in the three-dimensional rectangular coordinate system in (1); R is the radius of the ring where the torus a2 is located; (4) According to the above step (3), the coordinate values ​​of all points on the annular surface of the annular body a2 mapped to the spiral trajectory m1 are calculated in sequence, and then these points are connected in sequence with lines to obtain the spiral trajectory m2.

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