CN203008123U - Folding tubular structure with rigidity free degree - Google Patents

Abstract

The utility model discloses a foldable tubular structure with a rigid degree of freedom, which is a tubular structure formed by end-to-end connection of a plurality of single-layer annular units, each single-layer annular unit is a prism with 2N sides, and is relatively Two adjacent prisms with 2N sides are connected by sharing the intersection line of 2N polygons on the intersecting surface formed by the end-to-end connection, and each of the prisms with 2N sides is composed of 2N rigid planar quadrilaterals The ridges of each prism are parallel to each other, and the end-to-end ridges in the tubular structure are located in the same plane. When two adjacent single-layer ring units form a 2N polygon on the intersecting plane, there is only one symmetry When the line symmetry of the axis is a 2N polygon, the planes where the end-to-end ridges of the tubular structure are located are all perpendicular to the axis of symmetry. The device can be used to precisely control the folding and unfolding process of the structure.

Description

Foldable tubular structure with one rigid degree of freedom

technical field

The utility model relates to a foldable structure, in particular to a foldable tubular structure with a rigid degree of freedom.

Background technique

The expandable and foldable tubular structure composed of planar units has multiple uses, for example, it can be used as a large component of a space station, or even the construction of a moon base, or it can be used as a support for human blood vessels, digestive tract, etc., or it can replace a board room as a Large, medium and small temporary shelters after severe natural disasters. Such a tubular structure constructs a space with a specified volume after unfolding. At the same time, such a tubular structure can be folded to minimize its own volume, which is convenient for storage and transportation. In recent years, different forms of foldable tubular structures proposed by researchers such as Hoberman (US4780344, US4981732, US5234727), Guest and Pellegrino, Sogame (US6233880B1) and Furuya, and Nojima have the above-mentioned unfolding and folding functions, but Since the folding and unfolding functions of these structures depend on large elastic-plastic deformations of the materials used, it is difficult to precisely control the folding and unfolding process, which limits their usefulness. Moreover, the existing tubular folded structure is usually used as a disposable structure due to the change of the overall shape due to the deformation of the structural constituent units.

Contents of the invention

The purpose of the utility model is to overcome the deficiencies of the prior art, to provide a reusable and reusable folding and unfolding process with a rigid degree of freedom. Fold the tubular structure.

The utility model has a foldable tubular structure with a rigid degree of freedom, which is a tubular structure formed by end-to-end connection of multiple single-layer annular units, each single-layer annular unit is a prism with 2N sides, adjacent The two prisms with 2N sides are connected by sharing the intersection line of 2N polygons on the intersecting surface formed by the end-to-end connection, each of the prisms with 2N sides is composed of 2N rigid planar quadrilateral units Composition, the two adjacent single-layer annular units include 2N spherical mechanisms with only four planar quadrilateral units intersecting at one vertex, and the adjacent two single-layer annular units are in The 2N-gon formed by the intersecting surfaces is a line-symmetric 2N-gon or a central symmetric plane 2N-gon with a symmetry axis, and the ridges of each of the prisms with 2N sides are parallel to each other, and in the tubular structure The ridges connected end to end are located in the same plane, and when the 2N polygon formed by two adjacent single-layer annular units on the intersecting surface is a line-symmetric 2N polygon with only one axis of symmetry, the tubular The planes where the ridges connecting the end to end of the structure are located are all perpendicular to the axis of symmetry, and the said N is an integer greater than 1.

The device of the utility model has the following advantages:

A foldable tubular structure composed of a planar unit that will not deform and the connection line of two adjacent planar units as the center of rotation of the revolving pair can precisely control the folding and unfolding process of the structure; moreover, this structure As a mechanism with only one rigid degree of freedom, the complexity of unfolding and folding of the structure is reduced, and the structure is more reliable and reusable than existing structures.

The design method of the tubular structure described in the utility model is simple, and the assembly is convenient. Since it can be completely folded into a state with a small volume, the storage and transportation of the structure are very convenient. It is not limited to a certain shape or size of the tubular structure, but also meets the needs of constructing structures for different purposes.

Description of drawings

Figure 1 is a first embodiment of the foldable tubular structure with one rigid degree of freedom of the present invention, that is, a schematic diagram of the foldable tubular structure composed of quadrangular prism single-layer units in an unfolded state. In this structure, two adjacent layers The line of intersection is a line-symmetrical quadrilateral, that is, a kite-shaped, with one axis of symmetry;

Fig. 2 is a structural schematic diagram of the foldable tubular structure shown in Fig. 1 in a fully folded state;

3 is a schematic diagram of adjacent two-layer annular structures forming the foldable tubular structure shown in FIG. 1;

Fig. 4 is a top view of the annular structure shown in Fig. 3;

Fig. 5 is the concave folded state of the ring structure shown in Fig. 3, and the intersection line of two adjacent layers is transformed from a convex kite shape to a concave kite shape;

Fig. 6 is a top view of the concave folded state of the annular structure shown in Fig. 5;

Fig. 7 is a concave folded state of the foldable tubular structure shown in Fig. 1, and also a result diagram of superposition and connection of the ring structure shown in Fig. 5;

Fig. 8 is a structural schematic diagram of the foldable tubular structure shown in Fig. 7 in a fully folded state;

Fig. 9 is a second embodiment of the foldable tubular structure with one rigid degree of freedom of the present invention, that is, a schematic diagram of a foldable tubular structure composed of a single layer of quadrangular prisms in an unfolded state. In this structure, two adjacent layers The line of intersection is a centrosymmetric quadrilateral, and the center of symmetry is at the intersection of the diagonals of the quadrilateral.

Fig. 10 is a schematic diagram of the foldable tubular structure shown in Fig. 9 in a fully folded state;

Fig. 11 is a schematic diagram of adjacent two-layer annular structures forming the foldable tubular structure shown in Fig. 9;

Fig. 12 is a top view of the annular structure shown in Fig. 11;

Fig. 13 is a third embodiment of the foldable tubular structure with one rigid degree of freedom of the present invention, that is, a schematic diagram of a foldable tubular structure composed of a single layer of hexagonal prisms in an unfolded state. In this structure, the intersection of two adjacent layers The line is a line-symmetric hexagon with one axis of symmetry;

Fig. 14 is a schematic diagram of the foldable tubular structure shown in Fig. 13 in a fully folded state;

Fig. 15 is a schematic diagram of adjacent two-layer annular structures forming the foldable tubular structure shown in Fig. 13;

Fig. 16 is a top view of the annular structure shown in Fig. 15;

Figure 17 shows the concave folded state of the annular structure shown in Figure 15, and the intersection line of two adjacent layers is transformed from a convex hexagon to a concave hexagon;

Fig. 18 is a top view of the annular structure shown in Fig. 17;

Fig. 19 is a concave folded state of the foldable tubular structure shown in Fig. 13, and it is also a result diagram of superposition and connection of the ring structure shown in Fig. 17;

Fig. 20 is a schematic diagram of the foldable tubular structure shown in Fig. 19 in a fully folded state;

Figure 21 is a schematic diagram of the fourth embodiment of the foldable tubular structure with one rigid degree of freedom of the present invention, that is, a foldable tubular structure composed of a single layer of hexagonal prisms in an unfolded state. In this structure, two adjacent layers The line of intersection is a centrosymmetric hexagon, and the center of symmetry is located at the intersection of the diagonals of the hexagon;

Fig. 22 is a schematic diagram of the foldable tubular structure shown in Fig. 21 in a fully folded state;

Fig. 23 is a schematic diagram of a ring structure forming the foldable tubular structure shown in Fig. 21;

Fig. 24 is a top view of the annular structure shown in Fig. 23;

Fig. 25 is a sixth embodiment of a foldable tubular structure with one rigid degree of freedom of the present invention, that is, a schematic diagram of a foldable tubular structure composed of a single layer of octagonal prisms in an unfolded state. In this structure, the intersection of two adjacent layers The line is a line-symmetric octagon with one axis of symmetry;

Fig. 26 is a schematic diagram of the foldable tubular structure shown in Fig. 25 in a fully folded state;

Fig. 27 is a schematic diagram of adjacent two-layer annular structures forming the foldable tubular structure shown in Fig. 25;

Fig. 28 is a top view of the annular structure shown in Fig. 27;

Fig. 29 is a sixth embodiment of the foldable tubular structure with one rigid degree of freedom of the present invention, that is, a schematic diagram of a foldable tubular structure composed of a single layer of octagonal prisms in an unfolded state. In this structure, two adjacent layers The line of intersection is a centrosymmetric octagon, and the center of symmetry is located at the intersection of the diagonals of the octagon;

Fig. 30 is a schematic diagram of the foldable tubular structure shown in Fig. 29 in a fully folded state;

Fig. 31 is a schematic diagram of adjacent two-layer annular structures forming the foldable tubular structure shown in Fig. 29;

Figure 32 is a top view of the annular structure shown in Figure 31;

Fig. 33 is a seventh embodiment of a foldable tubular structure with one rigid degree of freedom of the present invention, that is, a schematic diagram of a foldable elbow structure composed of single-layer units corresponding to the same angle of intersection line in an unfolded state;

Fig. 34 is a schematic diagram of the foldable elbow structure shown in Fig. 33 in a fully folded state;

Fig. 35 is the initial stage of constructing the structure shown in Fig. 33, and a ring structure is formed as the basis of the structure shown in Fig. 33 by two intersecting lines corresponding to the same single layer;

Figure 36 is a schematic diagram of adding a new single-layer ring unit on the basis of the structure shown in Figure 35;

Figure 37 is a schematic diagram of adding a new single-layer ring unit on the basis of the structure shown in Figure 36;

Fig. 38 is the eighth embodiment of the foldable tubular structure with one rigid degree of freedom of the present invention, that is, the front view of the foldable elbow structure composed of any single-layer unit;

Fig. 39 is a left view of the foldable elbow structure composed of any single-layer unit shown in Fig. 38;

Fig. 40 is a top view of the foldable elbow structure composed of any single-layer unit shown in Fig. 38;

Fig. 41 is a schematic diagram of the foldable elbow structure composed of any single-layer unit shown in Fig. 38;

Fig. 42 is a schematic diagram of the ninth embodiment of the foldable tubular structure with one rigid degree of freedom of the present invention, that is, a foldable elbow structure composed of a single layer of hexagonal prisms in an unfolded state;

Fig. 43 is a schematic diagram of the foldable elbow structure shown in Fig. 42 in a fully folded state;

in:

1- A foldable tubular structure composed of a single layer of quadrangular prisms, the intersection of two adjacent layers is a line-symmetrical quadrilateral with a symmetric axis

2- A foldable tubular structure composed of a single layer of quadrangular prisms, and the intersection line of two adjacent layers is a centrally symmetrical quadrilateral

3- A foldable tubular structure composed of a single layer of hexagonal prisms, the intersection of two adjacent layers is a line-symmetric hexagon with a symmetrical axis

4- A foldable tubular structure composed of a single layer of hexagonal prisms, and the intersection line of two adjacent layers is a centrally symmetrical hexagon

5- A foldable tubular structure composed of a single layer of octagonal prisms, the intersection of two adjacent layers is a line-symmetric octagon with a symmetrical axis

6- A foldable tubular structure composed of a single layer of octagonal prisms, and the intersection line of two adjacent layers is a centrosymmetric octagon.

7- A foldable elbow composed of the same single-layer units at the angle of intersection

8-Foldable elbow composed of arbitrary single-layer units

9-Example of a foldable elbow structure composed of a hexagonal prism monolayer

i1 - the unfolded state of structure i (i=1,2,3,4,5,6,7,8,9)

i2 - fully folded state of structure i (i=1,2,3,4,5,6,7,8,9)

i3-The cyclic structure of structure i, consisting of two adjacent single-layer cyclic units (i=1,2,3,4,5,6,7)

i4-ring structure i3 is in a concave folded state (i=1,3)

i5 - unfolded state of structure i when in concave folded state (i=1,3)

i6 - folded state of structure i when in concave folded state (i=1,3)

iX-The intersection point of four planar units in structure i, which represents the center of the spherical mechanism, is also the vertex of the intersection line of two adjacent layers in the ring structure (X=A, B, C, D, E, F, G, H )

iXj-the intersection j of the vertex X in the structure i, the edge of the intersection of two adjacent layers in the ring structure (j=1,2,3,4). Viewed from the outside of the tubular structure, the four intersection lines are numbered counterclockwise around the vertex iX.

iXj(j+1)-the angle between the intersection line j and the intersection line j+1 intersecting at the vertex X in the structure i

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in detail.

The utility model has a foldable tubular structure with a rigid degree of freedom, which is a tubular structure formed by end-to-end connection of multiple single-layer annular units, each single-layer annular unit is a prism with 2N sides, adjacent The two prisms with 2N sides are connected by sharing the intersection line of 2N polygons on the intersecting surface formed by the end-to-end connection, each of the prisms with 2N sides is composed of 2N rigid planar quadrilateral units Composition, the two adjacent single-layer annular units include 2N spherical mechanisms with only four planar quadrilateral units intersecting at one vertex, and the adjacent two single-layer annular units are in The 2N-gon formed by the intersecting surfaces is a line-symmetric 2N-gon or a central symmetric plane 2N-gon with a symmetry axis, and the ridges of each of the prisms with 2N sides are parallel to each other, and in the tubular structure The ridges connected end to end are located in the same plane, and when the 2N polygon formed by two adjacent single-layer annular units on the intersecting surface is a line-symmetric 2N polygon with only one axis of symmetry, the tubular The planes where the ridges connecting the end to end of the structure are located are all perpendicular to the axis of symmetry, and the said N is an integer greater than 1.

The tubular structure may be a straight tube structure, and the planar quadrilateral unit is a parallelogram. The straight pipe structure includes two adjacent single-layer annular units forming a 2N polygon on the intersecting plane, which is a kite shape or a concave kite shape with a symmetrical axis, a centrally symmetrical quadrilateral, and a square with a symmetrical axis. Line-symmetric hexagon or concave hexagon, centrosymmetric hexagon, line-symmetric octagon or centrosymmetric octagon.

Said tubular structure may be a curved pipe structure with a bending axis. The planar quadrilateral units of the elbow structure are all trapezoidal or partially trapezoidal.

In the structure of the utility model, the intersection lines of adjacent planar quadrilateral units are equivalent to the rotation center axis of a revolving pair, and there are only four intersection lines intersecting at the same vertex, which is equivalent to a spherical 4R mechanism and has a rigid degrees of freedom. The connection that there are and only four planar quadrilateral units intersecting at one vertex ensures that the folding movement of adjacent two layers of annular units has only one rigid degree of freedom. Furthermore, it is ensured that the formed tubular structure has a rigid degree of freedom. The tubular structure expands and folds radially while expanding and folding axially. The fully expanded state of the tubular structure is achieved when a certain elementary combination of structures is maximally expanded. The fully collapsed state of the tubular structure is achieved when the planar quadrilateral unit is in surface contact with an adjacent unit.

The utility model is described in detail again below in conjunction with each accompanying drawing:

FIG. 1 is a schematic diagram of a foldable tubular structure 1 with one rigid degree of freedom composed of a single layer of quadrangular prisms in the unfolded state 11 , and FIG. 2 is a schematic diagram of the structure 1 in a fully folded state 12 . FIG. 3 is a schematic diagram of two adjacent two-layer annular units 13 forming the structure shown in FIG. 1 . In Fig. 3, two adjacent single-layer annular units are connected by two quadrangular prisms sharing an intersection line on the same plane, and each quadrangular prism is composed of four rigid planar quadrilateral units. The two adjacent single-layer annular units include four spherical mechanisms formed by intersecting one vertex with only four planar quadrilateral units, and the vertices are respectively 1A, 1B, 1C and 1D. The polygon formed by two adjacent single-layer annular units on the intersecting plane is kite-shaped 1A1B1C1D as shown in FIG. 3 , and has a symmetry axis. The symmetry axis coincides with the diagonal line 1A1C as shown in FIG. 4 .

The four ridgelines of each quadrangular prism monolayer are parallel to each other, that is, the ridgelines 1A1 , 1B3 , 1C1 and 1D3 are parallel to each other as shown in FIG. 3 . At the same time, in addition to satisfying the parallel relationship, each group of head and tail ridgelines must be located on the same plane, and this plane must be perpendicular to the axis of symmetry 1A1C, for example, the plane 1A11A3 where the two ridgelines are located in Figure 3 (1A3 is one of the single The ridge line of the layer, not shown in the figure), 1B31B1, 1C11C3 and 1D31D1 are all perpendicular to the axis of symmetry 1A1C. 1A2 , 1A4 , 1B4 , 1B2 , 1C2 , 1C4 , and 1D4 in the figure are respectively the ridgelines that can be seen in this view of the two quadrangular prisms in FIG. 3 .

The annular structure 14 shown in Fig. 5 and Fig. 6 is the configuration of the apex 1C in the annular structure 13 shown in Fig. 3 during the movement process approaching the apex 1A, and the annular structure 13 enters into a state having a In the folded state 14 of the concave kite-shaped cross-section. Figures 7 and 8 show, respectively, the unfolded state 15 and the fully folded state 16 of the foldable tubular structure 1 in the concave folded state. In contrast, the fully folded state 16 shown in FIG. 8 further reduces the space occupied by the structure compared to the fully folded state 12 shown in FIG. 2 .

Figure 9 shows the unfolded state 21 of the foldable tubular structure 2 consisting of a single layer of quadrangular prisms. FIG. 10 , FIG. 11 and FIG. 12 respectively show the fully folded state 22 of the structure 2 , the ring structure 23 constituting the structure 2 and the top view of the ring structure 23 . As shown in FIG. 11 , the annular structure 23 is the same as the annular structure 13 shown in FIG. 3 , and is composed of two adjacent quadrangular prisms connected by sharing an intersection line on the same plane. The ridge lines of each quadrangular prism are parallel, as shown in the figure, the ridge lines 2A1, 2B3, 2C1, and 2D3 in the upper quadrangular prism single layer are parallel; the ridge lines 2A3, 2B1, 2C3, 2D1 in the lower quadrangular prism single layer are parallel. Each group of end-to-end ridges is also located on the same plane. The difference is that the intersection of the two adjacent quadrangular prisms is a centrosymmetric quadrilateral 2A2B2C2D as shown in FIG. 12 , and its center of symmetry is the intersection of diagonals 2A2C and 2B2D as shown in FIG. 12 .

FIG. 13 shows that the foldable tubular structure 3 composed of a single layer of hexagonal prisms of the present invention is in an unfolded state 31 . FIG. 14 , FIG. 15 and FIG. 16 respectively show the structure 3 in the fully folded state 32 , the ring structure 33 constituting the structure 3 and the top views of the ring structure 33 . As shown in FIG. 15 , the annular structure 33 is formed by connecting two adjacent hexagonal prisms. The intersection line is a line-symmetric hexagon 3A3B3C3D3E3F, and the axis of symmetry passes through vertices 3A and 3D as shown in FIG. 16 . The six ridges of each hexagonal prism are parallel to each other, that is, as shown in Figure 15, the ridges 3A1, 3B3, 3C1, 3D3, 3E1 and 3F3 are parallel, while 3A3, 3B1, 3C3, 3D1, 3E3 and 3F1 are parallel (not shown in the figure show the serial number). Each group of end-to-end ridgelines on the tubular structure 31 shown in FIG. 13 is located on the same plane, and the plane is perpendicular to the symmetry axis of the intersection lines of adjacent hexagonal prisms.

FIG. 17 shows the annular structure 33 in FIG. 15 in a concave folded state 34 . FIG. 18 , FIG. 19 and FIG. 20 respectively show the top view of the ring structure 34 , the expanded state 35 and the fully folded state 36 of the tubular structure formed by the ring structure 34 .

Figure 21 shows the unfolded state 41 of the foldable tubular structure 4 composed of a hexagonal prism single layer of the present invention, and Figure 22, Figure 23 and Figure 24 show that the tubular structure 4 is in a fully folded state 42 respectively, forming the structure 4 The ring structure 43 and the top view of the ring structure 43. Different from structure 3, as shown in FIG. 23, the intersection line of adjacent hexagonal prisms forming the ring structure 43 is a centrosymmetric hexagon 4A4B4C4D4E4F, and the center of symmetry is the diagonal lines 4A4D, 4B4E and The intersection of 4C4F. The ridges of the hexagonal prisms in the ring structure 43 are parallel respectively, that is, 4A1, 4B3, 4C1, 4D3, 4E1 and 4F3 are parallel, and 4A3, 4B1, 4C3, 4D1, 4E3 and 4F1 are parallel (the serial number is not shown in the figure). The connecting ridges of vertices in the tubular structure 41 must lie on the same plane. The structure 4 also functionally has a fully unfolded state as well as a concave or convex folded state.

Fig. 25, Fig. 26, Fig. 27 and Fig. 28 show that the foldable tubular structure 5 composed of octagonal prism single layer of the present utility model is in the unfolded state 51, and is in the fully folded state 52, forming the annular structure 53 of the structure 5 And the top view of the ring mechanism 53. The intersection line of adjacent octagonal prism units shown in FIG. 27 is an octagon 5A5B5C5D5E5F5G5H, which has a symmetry axis and passes through vertices 5A and 5E shown in FIG. 28 . Similar to the aforementioned structures, the structure 5 also has a fully unfolded state and a concave or convex folded state functionally. The eight ridges of each octagonal prism are parallel to each other, that is, 5A1, 5B3, 5C1, 5D3, 5E1, 5F3, 5G3, and 5H3 are parallel to each other. Same as the aforementioned structure with a cross-section of a symmetric axis, each group of end-to-end ridges of the structure 51 are located on the same plane, and these planes are all perpendicular to the symmetry axis of the intersection lines of adjacent octagonal prisms. Functionally, the structure 5 also has a fully unfolded state as well as a concave or convex folded state.

Fig. 29, Fig. 30, Fig. 31 and Fig. 32 show that the foldable tubular structure 6 composed of octagonal prism single layer of the present utility model is in the unfolded state 61, is in the fully folded state 62, and forms the annular structure 63 of the structure 6 And a top view of the annular structure 63 . Structure 6 has the same unfolding and folding functions as structure 5, the parallel conditions of the ridges in each single layer and the coplanar conditions of the connected ridges. Ridge lines 6A1, 6B3, 6C1, 6D3, 6E1, 6F3, 6G3, and 6H3 are parallel to each other. Different from structure 5, as shown in Figure 31 and Figure 32, the intersection line 6A6B6C6D6E6F6G6H of two adjacent octagonal prism single layers in structure 63 is centrosymmetric, and the center of symmetry is the intersection point of diagonal lines 6A6E, 6B6F, 6C6G and 6D6H . Functionally, the structure 6 also has a fully unfolded state as well as a concave or convex folded state.

The foldable tubular structure composed of quadrangular prism, hexagonal prism and octagonal prism monolayer can be extended to the foldable tubular structure composed of 2N prism monolayer, and has the corresponding unfolding and folding functions. The parallel conditions of the ridge lines in each monolayer and the coplanar condition of connected ridges. When the intersection line of adjacent 2N prisms has a symmetry axis, the plane where each group of end-to-end ridgelines is located also needs to be perpendicular to the symmetry axis.

From FIG. 33 to FIG. 41 , the construction structure of the foldable elbow structure is introduced by enumerating specific examples of the elbow structure composed of a quadrangular prism single layer. These structures for building bent pipes are also applicable to the construction of foldable bent pipe structures composed of hexagonal prisms, octagonal prisms, and even 2N prism monolayers.

Figure 33 and Figure 34 respectively show the unfolded state 71 and the fully folded state 72 of the foldable elbow structure 7 composed of single-layer units with the same angle of intersection. 73 is the ring structure forming the structure. Figure 35, Figure 36 and Figure 37 show the process of building structure 7, adding a single layer on top of the previous structure from top to bottom. The single-layer units in the elbow structure 7 are connected by four plane trapezoids to form a ring structure. Each monolayer in structure 7 is built on the basis of the previous monolayer, and is not necessarily the same as the other monolayers. The rules followed in the construction of a single layer are as follows: 1) The angle of intersection of the constructed single layer is the same as the corresponding angle of the previous single layer, for example, 7B23=7B12, 7C12=7C23, 7C41=7C34, 7D34= 7C41. Because the ridgelines 7A3 (not shown in the figure), 7B1, 7C3 and 7D1 in the previous single layer are parallel to each other, the ridgelines 7A1, 7B3, 7C1 and 7D3 in this single layer are also parallel to each other. 7B2 and 7D4 are intersection lines on the intersection surfaces of two adjacent prisms. 2) The intersection line between the constructed single layer and the previous single layer is always a line-symmetric or centrally symmetrical plane 2N polygon, as shown in Figure 35, the cross-section 7A7B7C7D is a line-symmetric quadrangle. 3) When constructing a single layer, it must be satisfied that the ridge line should be located in the same plane as the ridge line of the previous single layer connected to it. When the intersection line of two adjacent layers is a line-symmetric 2N polygon with only one axis of symmetry, These planes must all be perpendicular to the axis of symmetry.

Fig. 38, Fig. 39, Fig. 40 and Fig. 41 are respectively the front view, left side view, top view and structural appearance schematic diagram of the foldable elbow structure 8 composed of any single-layer unit. Similar to structure 7, structure 8 is also constructed by adding a single layer, and the constructed structure must meet the following conditions: 1) The intersection line between each single-layer unit and the previous single-layer unit is line-symmetric or central A symmetrical planar 2N polygon, such as a line-symmetrical quadrilateral 8A8B8C8D as shown in FIG. 41 . 2) The ridgelines in each single-layer unit are parallel to each other 3) Each group of end-to-end ridgelines in the entire tubular structure is located on the same plane. When the intersection line 2N polygon of adjacent two-layer units has only one symmetry axis, these Both planes must be perpendicular to the axis of symmetry. The difference between structure 8 and 7 is that the angle of the intersection line in each single layer in structure 8 is not the same as the corresponding angle of the adjacent two layers, and therefore structure 8 cannot always achieve surface contact between adjacent plane elements. In the fully folded state, usually only the single layer with the smallest foldable range reaches the fully folded or fully unfolded state. Compared with the elbow structure 7, the construction constraints of the structure 8 are the least, so the structure 8 is the most common case of the foldable elbow structure, and the construction rule of the structure 8 also includes the construction of all the aforementioned foldable straight pipe structures in the utility model. the law.

Fig. 42 and Fig. 43 illustrate an elbow structure designed and established by the method for building an elbow described above, which are the unfolded state 91 and the fully folded state 92 of the elbow structure 9 composed of a single layer of hexagonal prisms.

At the same time, it needs to be explained: 1) When all the planar quadrilaterals in the structure are parallelograms, the constructed tubular structure with 2N prisms as a single layer behaves as a foldable straight tube structure, such as structures 1, 2, 3, and 4 , 5, and 6; 2) When some or all of the planar quadrilaterals in the structure are trapezoidal, the constructed tubular structure with a single layer of 2N prisms behaves as a bendable bend structure, such as structures 7, 8, and 9. Thereby the straight pipe structure is a special case of the bent pipe structure, both of which are within the protection scope of the present utility model.

The above schematically describes the utility model and its implementation, which is not restrictive, and what is shown in the accompanying drawings is only one implementation of the utility model, and the actual structure is not limited thereto. Therefore, if those skilled in the art are inspired by it, without departing from the purpose of the utility model, they can use planar quadrilateral units of different materials to construct the structure of the utility model, or use other forms of connection combinations without creative design. Structural manners and embodiments similar to the structure of the utility model shall belong to the protection scope of the utility model.

Claims (5)

1. the collapsible tubular structure that has a rigidity degree of freedom, it is characterized in that: its tubular structure for being connected to form from beginning to end by a plurality of individual layer annular units, each individual layer annular unit is the prism with 2N side, adjacent two prisms with 2N side are connected to form by the mode that shares the 2N limit shape intersection that is positioned on the phase cross surface that head and the tail are connected to form, the prism of each described 2N of having side is comprised of 2N rigid plane quadrilateral units, two adjacent described individual layer annular units comprise that 2N has and only have four plane quadrilateral unit to intersect at the spherical mechanism that a summit forms, two adjacent described individual layer annular units form in the phase cross surface 2N limit shape is the symmetrical 2N limit shape of line or the Center Symmetry Plane 2N limit shape with an axis of symmetry, the crest line of the prism of each described 2N of having side is parallel to each other, in described tubular structure, end to end crest line is positioned at same plane, the 2N limit shape that forms in the phase cross surface when two adjacent described individual layer annular units is during for the symmetrical 2N of the line limit shape that only has an axis of symmetry, the plane, end to end crest line place of described tubular structure is all perpendicular to axis of symmetry, described N is the integer greater than 1.

2. collapsible tubular structure with a rigidity degree of freedom described according to right 1, it is characterized in that: described tubular structure is straight tube structure, described plane quadrilateral unit is parallelogram.

3. the collapsible tubular structure with a rigidity degree of freedom according to claim 2 is characterized in that: described straight tube structure comprises that two adjacent described individual layer annular units form in the phase cross surface 2N limit shape is zither shape or recessed zither shape, the Central Symmetry quadrangle with an axis of symmetry, the symmetrical hexagon of line with an axis of symmetry or recessed hexagon, Central Symmetry hexagon, the symmetrical octagon of line or Central Symmetry octagon.

4. collapsible tubular structure with a rigidity degree of freedom described according to right 1, it is characterized in that: described tubular structure is the bend pipe structure with axis of bending.

5. collapsible tubular structure with a rigidity degree of freedom described according to right 4 is characterized in that: the plane quadrilateral unit of described bend pipe structure be all trapezoidal or part for trapezoidal.

Images