JP2012163201A - Expansion pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expansion pipe which has a sufficiently large amount of expansion, has wide flexibility in design, allows easy processing method, and can be applied to various materials.SOLUTION: The expansion pipe employs a tubular development structure which can be molded only by bending a flat plate and minimum welding based on a shape formed by combining two polyhedral faces comprising a trapezoid and a parallelogram, and allows a large amount of expansion, does not require complicated plastic work and can be applied to various materials.

Description

The present invention relates to a telescopic tube. More specifically, the present invention relates generally to a telescopic tube or tube structure in a broad sense, and relates to fields such as the machine industry, chemical industry, architecture, and civil engineering.

The problem with current technology in the production of telescopic tubes is that a large plastic deformation process is required. Since a thin-walled cylinder is inherently a very stable structure, in order to expand and contract it in the axial direction, in the current technology, the tube wall is formed into a deep zigzag (wave shape or saw blade type) shape along the axial direction. In order to manufacture such a complicated shape from a plate as a raw material, a large plastic working is inevitably required. Further, the zigzag obtained as a result of the zigzag contracts in the axial direction to become flatter, and as a result, tries to protrude outside the inner wall and the outer wall. However, since the inner wall and the outer wall each form a closed circumference, the inner wall and the outer wall are restrained, and the amount of expansion and contraction obtained is limited. Therefore, large plastic working and the limit of the amount of expansion and contraction obtained thereby inevitably lead to problems such as cost, material selection limitation, size limitation, and the like.

The reason why the use of the telescopic tube is limited to a relatively narrow range seems to be due to the above-mentioned problems. If there is a concept that can be manufactured relatively easily and inexpensively using a rigid material such as metal, the fields in which the telescopic tube can be used will be widened and beneficial. For the above reasons, there has been a demand for a new expansion tube construction principle that does not involve large plastic deformation. Recently, an invention deeply related to this problem has been proposed (Patent Document 1). This has the potential to bring new progress in this area.

Patent application 2009-239831

An object of the present invention is to provide a sufficiently large expansion / contraction amount, a wide range of design freedom, an easy processing method, and a novel expansion / contraction tube applicable to various materials.

As shown in claim 1 of the present invention, the telescopic tube 11 and the joint block 12 are constituent elements, and the shape of the telescopic tube is based on the pattern A and the pattern B shown in the folding design drawing, The pattern A has an isosceles trapezoid 3 in which an upper base and a lower base 3-1 are placed on the parallel lines in the band-like region 2 defined by two parallel lines 1 in the X-axis direction on the XY plane. Symmetrically on both sides of the trapezoidal trapezoid, a plurality of parallelograms 4 having an inclination angle 3-3 equal to the hypotenuse 3-2 of the isosceles trapezoid and having the parallel lines as two sides are arranged without gaps. This is the basic area A1, and starting from the basic area A1, a mirror image A2 having one parallel line of the basic area as a mirror is formed, and a mirror image A3 that is a mirror image of the mirror image A2 is formed by a similar operation. The pattern A is formed by repeating this process sequentially, and the pattern On the XY plane, the first mirror image A2 is set as B1, and the pattern B is formed by sequentially repeating the same operation as the pattern A, starting from B1, and the pattern A and the pattern B. All the sides of the isosceles trapezoid and the parallelogram included in the folds are creased, and the mountain folds and folds of the creases are determined as the folds of the oblique sides of the isosceles trapezoids, and the folds on the parallel lines are sandwiched All the dihedral angles β are made equal, and the basic regions of the patterns A and B are matched to each other on the back side such as A1 and B1, A2 and B2, A3 and B3, etc. It joins with the corresponding part 5-1 of the parallelogram 5 of an edge part, and makes it the shape of an expansion-contraction pipe | tube, materializes this shape with a board | plate material, and makes a joint block in the edge part of this expansion-contraction pipe | tube. Bind and restrain The above-mentioned problem is to be solved by the telescopic tube assembly 10 that expands and contracts within a certain range.

Further, as shown in claim 2 of the present invention, in the claim 1, the expansion tube assembly 10 is characterized in that the dihedral angle β is 60 degrees or less.

According to a third aspect of the present invention, there is provided a method of manufacturing the telescopic tube 11 based on the pattern A and the pattern B shown in the folding design drawing. The pattern A is two parallel in the X axis direction on the XY plane. An isosceles trapezoid 3 in which the upper and lower bases 3-1 are placed on the parallel lines is arranged in the belt-like region 2 defined by the line 1, and the hypotenuse 3 of the isosceles trapezoid is symmetrical on both sides of the isosceles trapezoid. -2 having an inclination angle 3-3 equal to -2 and having parallel lines as two sides, and arranging a plurality of even numbers without gaps, this is defined as a basic region A1, starting from the basic region A1, A mirror image A2 is formed with one parallel line in the basic region as a mirror, and further, a mirror image A3 that is a mirror image of the mirror image A2 is formed by a similar operation. B represents the first mirror image A2 on the XY plane as B1, and B The pattern A is formed by repeating the same operation as the pattern A, and the pattern A and the pattern B are all creased in the sides of the isosceles trapezoid and the parallelogram included therein. The crease mountain fold valley fold is determined as a fold on the hypotenuse of the isosceles trapezoid, and all dihedral angles β sandwiching the folds on the parallel lines are made equal to each other. The B member is manufactured, and the basic areas of the pattern A member and the pattern B member are aligned on the back such as A1 and B1, A2 and B2, A3 and B3. It is an object of the present invention to solve the above-mentioned problem by a method for manufacturing a telescopic tube, characterized in that the joining process is performed at the corresponding parallelogram contact portions of the portions.

According to a fourth aspect of the present invention, there is provided a method for producing an expansion tube according to the third aspect, wherein the pattern A and the pattern B are processed by members having the same total sum but different divisions. Is to solve.

Further, as shown in claim 5 of the present invention, in the third and fourth aspects, the tube manufactured with a dihedral angle β is changed to a dihedral angle β1 by an axial load. The method is intended to solve the problem.

Since the principle of the present invention is completely different from the prior art, this will be described prior to the description of the effects of the invention. The first basic principle of the present invention is based on the use of Patent Document 1. FIG. 2 shows the expansion / contraction process, which has been proposed as a cylindrical expansion / contraction structure. The structure is composed of a polyhedral surface and a fold (hinge) corresponding to the ridge. Conceptually, it may be considered that two cylindrical faces are combined to form one cylindrical shape. In FIG. 2A, the two polyhedron surfaces are in a substantially flat state with the back surfaces being combined. At this time, the dihedral angle β between the pair of trapezoidal surfaces shown in the drawing is almost 180 degrees. This dihedral angle β is the only variable parameter of this shape if a component is given, and applies to all pairs of trapezoids and parallelograms, and of course uniquely determines the entire shape. Thereafter, the shape gradually changes as the parameter β decreases. In FIG. 2 (e), where β is almost zero, it is folded back into another flat state.

Now, the most notable point about the telescopic tube will be between FIGS. In this vicinity, there is a feature that the shape is a range that can be considered as a tube in common sense, and that the shape of the enclosed space is not significantly changed. This is shown in FIG. 3 as the relationship between the cross-sectional area S perpendicular to the tube axis and the dihedral angle β corresponding to FIG. By observing this, it is confirmed that the cross-sectional area S has a slight fluctuation in the sections of FIGS. 2 (d) and 2 (e). As far as this is seen, it seems that the structure of this section has the property that it can be easily used as a telescopic tube.

One problem lies in seeking a method for manufacturing such seemingly complex structures. This is composed of a large number of parallelogram and trapezoidal face plates and a large number of folds (hinges), and there are also pyramid shapes in the local area. However, considering the geometry of its composition, one basic property emerges and can be used to solve this problem.

When the structure around FIG. 2D is disassembled, it can be seen that the unit structure consisting of a simple face plate 13 and a crease 14 is actually repeated. FIG. 4A shows a planar unit member of the pattern A and the pattern B. FIG. This shows a crease, and if the hypotenuse of the trapezoid is designated as a mountain fold, the other creases are automatically determined. The three-dimensional pattern A and pattern B members are combined as shown in FIG. 4B (plan view, front view) to form one ring structure. The ring structure can be expanded and contracted along the central axis and, for example, contracts by about half as shown in FIG.

What is important here is that the face plate is rigid and the fold is a perfect hinge, and this deformation is done without any distortion. The fact that the face plate constituting the circumference is not deformed means that the circumference formed thereby is unchanged. Therefore, there is no restriction on the circumference in expansion and contraction, and it is performed freely. This fact is completely different from the conventional expansion tube in which the restriction of the circumferential length accompanying expansion and contraction is a problem as described above. In other words, it is understood that the restraint is eliminated by the unique deformation of the circumference. This is the first basic concept of the present invention.

In the unit structures shown in FIGS. 4B and 4C, the connection between the members of the pattern A and the pattern B is the ridge line 5-3, and the cylinder has a single wall structure including 5-2. In FIG. 4 (a)), the surface 5-1 extended from these ridgelines is indicated by a broken line, and in this case, the surfaces can be connected to each other on this surface or a further extended surface thereof. The basic properties of both are almost the same, but in the latter case, surface bonding may be advantageous in manufacturing.

The second basic principle of the present invention will be described below. This relates to a more practical embodiment. The tubular telescopic structure is obviously a deployed structure as shown in FIG. Therefore, it has a mechanism and its shape is indefinite. However, if it is actually made by bending a thin plate, both the surface and the hinge of the crease are elastic, and the property as an elastic structure is maintained. Specifically, the surface remains substantially rigid, but the angle of the elastic hinge is likely to change and its shape changes easily. Moreover, as an embodiment, when an expansion tube is used, the end portion thereof is used by being coupled and fixed to another member such as a collar. That is, at least theoretically, it loses the degree of freedom as a deployment structure and becomes a rigid body. Therefore, it is necessary to investigate a practical relationship between the fixation and the stretchability of the telescopic tube.

FIG. 1 shows an example of a telescopic tube assembly 10 in which the telescopic tube 11 is actually fixed to a joint block 12, and is suitable for the purpose of showing the practical relationship. FIG. 1A shows a value of a certain reference value (β = 20 degrees) in which both ends of the telescopic tube 11 are coupled to the joint block 12. FIG. 1B shows a slightly expanded state (β = 60 degrees). Obviously, the elongation is small in the vicinity of both ends, but it becomes clear that the stretched state becomes substantially uniform as the distance from the ends increases. Such a property is a phenomenon that can be explained by Saint-Venant's law in material mechanics, and shows the attenuation of the local influence at the end of the elastic body.

In the case of the present invention, the above phenomenon has two important meanings. First, the part excluding the end part behaves like a developed structure around the reference value β, so that a high expansion / contraction amount can be obtained with a low reaction force. Next, elastic deformation (including in-plane deformation) of the face plate is performed at the end portion, thereby acting as an elastic spring. As described above, the basic portion of the present invention conforms to the original expanded structure, and the main portion excluding the vicinity of the end of the tube functions as a substantially expanded structure. Therefore, it is easy to obtain a large expansion / contraction amount. The above is the second basic concept of the present invention when actually used.

The first effect of the present invention is that a large amount of expansion and contraction can be obtained as compared with a conventional expansion tube. The reason is that, as described above, the main part except the vicinity of the end of the tube functions as a substantially expanded structure.

The second effect of the present invention is that a structure having a complicated shape is produced from a flat material mainly by bending. Returning to the basic principle of the formation of the cylindrical stretchable structure, the answer can be seen why this is possible. The structure is originally defined using inextensible deformation from a flat plate. The non-extension deformation from the flat plate means that the deformation is performed only by bending outside the plate surface without any expansion or contraction in the plate surface. The closest image is to fold the paper. At this time, the paper does not stretch or shrink in the plane. If it has the property of non-extensional deformation, it can be made by a process of bending from a flat plate in principle. This is quite different from current expansion tubes that require large deformations in the plate surface and therefore require large plastic working.

The third effect is that the degree of freedom of material selection is large. As described above, since the processing method is mainly bending, it does not depend much on the ductility of the material. The materials that can be used for the expansion tube are limited by various fluid materials and various temperature environments. In addition, if the workability of the material is added, the range of selection is significantly narrowed at present.

The fourth effect is a relatively simple manufacturing method, a variety of raw material selections, and no size limit. As a result, there is a possibility of spreading the use to fields that have not been used before. For example, since this is a tubular spring, it can be used as a general spring. Regardless of its own spring characteristics, it can be used as a damping or shock energy absorbing element as a cylindrical casing that can be expanded and contracted by a composite structure in which an elastic-plastic material is filled inside the pipe. In short, it is possible to expand the telescopic tube, which has been limited to special applications, to more general usage.

Example 1 is a so-called telescopic tube assembly used in a pipeline or the like, and is shown in FIG. Reference numeral 10 denotes a telescopic tube assembly, of which 11 is a telescopic tube, 12 is a collar, 13 is a face plate, and 14 is a fold. To be precise, the face plate 13 is an elastic flat plate and the fold line 14 is an elastic hinge. Based on the principle described above, this structure is made up of an elastic surface and an elastic hinge. The smaller the angle of the elastic hinge 14 (typically, the dihedral angle β between trapezoids), the more flexible the structure. For flexible structures, Saint-Venant's principle is well adapted and the effects of the terminal are known to decay rapidly. FIG. 1a shows the initial state, and FIG. 1b shows the state extended about 50% from FIG. 1a. Observations show that the effect of the end restraint decays rapidly, resulting in a nearly steady shape at the center.

Again, in the case of the present invention, the above phenomenon has two important meanings. First, the part excluding the end part behaves like a developed structure around the reference value β, so that a high expansion / contraction amount can be obtained with a low reaction force. Next, elastic deformation (including in-plane deformation) of the face plate is performed at the end portion, thereby acting as an elastic spring. As described above, the basic portion of the present invention conforms to the original expanded structure, and the main portion excluding the vicinity of the end of the tube functions as a substantially expanded structure. Therefore, it is easy to obtain a large expansion / contraction amount.

Moreover, in carrying out the present invention, as observed with respect to FIGS. 1, 2, and 3, it was shown that there is a range in which the dihedral angle β can be easily used as a normal telescopic tube. In view of this, it is assumed that the reference value of the dihedral angle β is most preferably 60 degrees or less (FIG. 3). Of course, depending on the mode of use, use outside this range is not excluded.

Example 2 is a method for manufacturing a telescopic tube. Manufacture is a manufacturing method based on the pattern A and the pattern B shown in the folding design drawing (FIG. 5). In the pattern A, an isosceles trapezoid 3 in which an upper base 3-1 and a lower base 3-1 are placed on the parallel lines in a band-like region 2 defined by two parallel lines 1 in the X-axis direction on the XY plane. Arranged parallel to both sides of the isosceles trapezoid and having an inclination angle 3-3 equal to the hypotenuse 3-2 of the isosceles trapezoid and having the parallel lines as two sides, parallelograms 4, 5, 6. .. and a plurality of even numbers are arranged without gaps, and this is used as a basic area A1, and a mirror image A2 is formed starting from the basic area A1 with one parallel line of the basic area as a mirror, and the same operation is performed. A mirror image A3 that is a mirror image of the mirror image A2 is formed, and the pattern A is formed by repeating this sequentially.

The pattern B is a pattern B formed by repeating the same operations as those of the pattern A, starting from B1, on the XY plane, with the first mirror image A2 being B1.

For pattern A and pattern B, all sides of the isosceles trapezoid and parallelogram included in the pattern A and pattern B are defined as folds, and the folds and folds of the folds are determined as folds on the hypotenuses of the isosceles trapezoids, and X All dihedral angles β across the fold line parallel to the axis are made equal, and the pattern A member and the pattern B member are manufactured by bending the plate material. The basic areas of the pattern A member and the pattern B member are A1 and A1, respectively. B1, A2 and B2, A3 and B3, etc. are arranged facing each other on the back surface, and by joining and processing at the contact portions of the even-numbered parallelogram corresponding to the ends, the expansion tube is To manufacture.

The rules are as follows. All the sides of the isosceles trapezoid and the parallelogram included in these are folds, and the folds of the hypotenuses of the isosceles trapezoid are folds, and the other folds are folds that match them. In addition, about the vertex where four folds concentrate, the number of folds of a mountain fold and a valley fold is limited to 3 and 1 or 1 and 3. All the dihedral angles β between the opposite isosceles trapezoid and the parallelogram are given equally. Since these are all fold deformations and do not require in-plane distortion, they can be performed only by bending. Further, since the creases are related to each other, the folding process needs to be performed at the same time as the folds included in the member.

FIG. 6 shows a process of manufacturing a target folded plate telescopic tube from a flat plate material by bending (perspective view). FIG. 6A shows a plate on which a crease is transferred for reference to the pattern A. FIG. FIG. 6B shows a state in which the dihedral angle β is given an intermediate value by bending. FIG. 6C shows a state in which a dihedral angle β is given. FIG. 6 shows the coupling between the bending member of the pattern A in FIG. 6C and the bending member of the pattern B manufactured in the same manner (perspective view). At this time, the two are aligned on the back so that the planes of symmetry passing through the respective isosceles trapezoids are on the same plane.

In addition, as described in claim 5, the tubular form in which the pattern A and the pattern B are combined to form the dihedral angle β is expanded and contracted by applying a load in the axial direction to form the dihedral angle β1. can do. For example, when β is large, both patterns A and B are relatively flat, and a space for joining (welding, etc.) work is wide. Using this fact, a predetermined dihedral angle may be obtained after the coupling.

Example 3 shows that the telescopic tube of the present invention can be applied even when the axis is a plane curve. FIG. 7 shows a bent telescopic tube assembly 15. In addition, the bending rigidity of the expansion-contraction pipe | tube of this invention has orthogonal anisotropy, and the example of illustration has taken the direction which is easy to bend. On the other hand, in the case of using the property in a straight line, it is possible to use a direction in which the bending rigidity is large with respect to the gravity.

As Example 4, since this is a kind of tubular spring, it can be used as a spring in general. In general, the tubular shape is a stable shape, and the variety of choice of materials is noted. Moreover, it can be used as a damping or impact energy absorbing element by a composite structure in which an elastic-plastic material or the like is filled inside the pipe as a tubular casing that can be expanded and contracted regardless of its own spring characteristics. In short, it is possible to expand the telescopic tube, which has been limited to special applications, to more general usage.

The present invention proposes novel principles and applications for telescoping tubes and telescoping tube assemblies.

Telescopic tube assembly (front view) (a) Reference state (b) Extended state Deformation process of cylindrical telescopic structure (perspective view) (a), (b), (c), (d), (e) The relationship graph symbols of the cross-sectional area S and the dihedral angle β corresponding to the cylindrical expansion / contraction structure of FIG. 2 correspond to FIGS. 2 (a), (b), (c), (d), and (e). Principle of telescopic tube (a) Unit member (plan view) (b) Ring structure (plan view, front view) (c) Ring structure at the time of reduction (plan view, front view) Blueprint of telescopic tube (a) Pattern A (b) Pattern B Stretch tube manufacturing process (perspective view) (a) Initial state (b) Bending process in progress (c) End of bending process (d) Combination of pattern A and pattern B combined Curved telescopic tube assembly (front view)

DESCRIPTION OF SYMBOLS 1 Parallel line 2 Band-like area | region 3 Isosceles trapezoid 3-1 Isosceles trapezoid bottom 3-2 Isosceles trapezoid hypotenuse 3-3 Inclined angle of equilateral trapezoid hypotenuse
4 Odd-numbered parallelograms from the center 5 Even-numbered and end-side parallelograms 5-1 Even-numbered and end-sided parallelogram junctions 5-2 Even-numbered and end-side from the center Necessary minimum part of the parallelogram 5-3 The connecting line 6 between the minimum part of the parallelogram that is even from the center and the edge of the parallelogram 4 and the ridgeline of the parallelogram 4 Become)
10 Stretch tube assembly 11 Stretch tube 12 Joint block or collar 13 Face plate 14 Crease (hinge)
15 Curved telescopic tube assembly A pattern, and member B of its shape, and members A1, A2, A3, A4,. . . Basic area (Figure 5 (a))
B1, B2, B3, B4,. . . Basic area (Fig. 5 (b))
S Stretchable tube cross section X, Y Cartesian coordinate system β, β1 Dihedral angle across parallel line 1 (dihedral angle between trapezoidal surfaces (3 and 6))
····················· FIG.

Claims (5)

The telescopic tube and the joint block are constituent elements, and the shape of the telescopic tube is based on the pattern (A) and the pattern (B) shown in the folding design drawing, and the pattern (A) is the (XY) plane. (X) In the band-shaped region defined by two parallel lines in the axial direction, an isosceles trapezoid with the upper and lower bases placed on the parallel lines is disposed symmetrically on both sides of the isosceles trapezoid, A plurality of parallelograms having an inclination angle equal to the hypotenuse of the isosceles trapezoid and having the parallel lines as two sides and an even number of parallelograms are arranged without gaps, and this is defined as a basic region (A1). For the first time, a mirror image (A2) is formed by using one parallel line of the basic region as a mirror, and a mirror image (A3) that is a mirror image of the mirror image (A2) is formed by the same operation. The pattern is (A), and the pattern (B) is the (XY) plane. Then, the first mirror image (A2) is set to (B1), and the pattern (B) is formed by sequentially repeating the same operation as the pattern (A) starting from (B1). ) And the pattern (B), all the sides of the isosceles trapezoid and parallelogram included in the pattern (B) are creased, and the mountain fold valley fold of the crease is determined as the fold of the hypotenuse of the isosceles trapezoid, All dihedral angles (β) sandwiching the folds on the parallel lines are made equal, and the basic regions of the patterns (A) and (B) are (A1) and (B1), (A2) and (B2), As shown in (A3) and (B3)..., They are arranged to face each other on the back, and are combined at the even-numbered and corresponding parallelograms at the ends of the parallelograms to form a telescopic tube. Materialized with a plate material to form a telescopic tube, the end of the telescopic tube A telescopic tube assembly characterized by connecting and constraining a joint block to a section and expanding and contracting within a certain range. 2. The telescopic tube assembly according to claim 1, wherein the dihedral angle (β) is 60 degrees or less. This is a manufacturing method based on the pattern (A) and the pattern (B) shown in the folded design drawing. The pattern (A) is a band-shaped region defined by two parallel lines in the (X) axis direction on the (XY) plane. An isosceles trapezoid having an upper base and a lower base on the parallel line, symmetrically on both sides of the isosceles trapezoid, having an inclination angle equal to the hypotenuse of the isosceles trapezoid and the parallel lines as two sides A plurality of parallelograms are arranged without any gaps, and this is used as a basic region (A1). Starting from the basic region (A1), a mirror image (A2) having one parallel line of the basic region as a mirror is obtained. Then, a mirror image (A3) that is a mirror image of the mirror image (A2) is formed by the same operation, and the pattern (A) is formed by repeating this sequentially, and the pattern (B) is (XY) On the surface, the first mirror image (A2) is (B1) and starts from (B1) The pattern (B) is formed by sequentially repeating the same operation as the pattern (A), and all the sides of the isosceles trapezoid and parallelogram included in the pattern (A) and the pattern (B) Folds, and the folds and folds of the folds are determined as folds of the hypotenuses of the isosceles trapezoid, and all dihedral angles (β) sandwiching the folds on the parallel lines are made equal, and the plate material is bent The pattern (A) member and the pattern (B) member are manufactured by the above, and the basic areas of the pattern (A) member and the pattern (B) member are (A1) and (B1), (A2) and (B2), respectively. , (A3) and (B3)..., An expansion tube characterized by being combined at the back side and joined at the even-numbered and corresponding parallelogram contact portions at the ends. Manufacturing method. 4. A method for manufacturing an expandable tube according to claim 3, wherein the pattern (A) and the pattern (B) are processed by members having the same sum but different divisions. 5. A method of manufacturing an expansion / contraction tube according to claim 3 or 4, wherein the expansion / contraction tube manufactured at a dihedral angle ([beta]) is converted into a dihedral angle ([beta] 1) by an axial load.

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