JP2010096970A - Model of topological soliton circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a model of a topological soliton circuit. <P>SOLUTION: A hollow elastic shaft 11 is used which stores elastic energy as a restoring force when it is twisted in the circumference direction around the center axis, reduces its outside diameter ϕn inward in the radial direction when a tensile force is applied in the axial direction and it is extended in the axial direction, has a diameter expanding force serving as a restoring force outward in the radial direction, and has a restoring force also in the axial direction. A plurality of unit cells 12 are attachably and detachably fixed at intervals in the axial direction of the hollow elastic shaft 11. The unit cell is provided with a rotary drive shaft 51 which is inserted in the inside of the hollow elastic shaft 11 along the axial direction, has the outside diameter ϕr smaller than the inside diameter ϕi of the hollow elastic shaft and, therefore, is in contact with the inner peripheral surface of the hollow elastic shaft 11 at a position Pc vertically above the outer circumference surface of the hollow elastic shaft, and conveys a rotary drive force to the hollow elastic shaft 11 via a friction force at the contact portion Pc when it receives rotary drive. This rotary drive shaft 51 is rotated by a rotary drive mechanism capable of controlling the numbers of rotation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a model for visualizing and explaining the operation of a topological soliton circuit which is one of superconducting circuits.

Among the one-dimensional solitons, topological solitons that follow the Sine-Gordon equation have been used since the 1960s as recognized in the following non-patent document 1 as models of elementary particles and crystal transitions. It has been studied in detail.
Iwanami Lecture: Modern Physics 14, “Nonlinear Waves”, Miki Wada (ISBN4-00-010444-6), especially Section 3 p.34-p.42

However, this topological soliton is also of a type, and in addition to what is defined as flux quanta, called fluxon, a multiband superconductor is used as a transmission line, and the phase difference between multiple superconducting components is used. There is also an interband phase difference soliton that operates without the involvement of magnetic flux, and the latter is disclosed in, for example, the following Patent Documents 1 to 3 in which the present inventors are also involved.
Japanese Patent Laid-Open No. 2003-209301 Japanese Unexamined Patent Publication No. 2005-085971 JP 2008-053597

Actually, the interband phase difference solitons are also in a realistic research stage. Regarding the generation of the interband phase difference solitons, as disclosed in Patent Documents 1 and 2 and Non-Patent Document 2 below, the interband phase difference solitons are generated. A boundary condition for creating a boundary condition by using a magnetic field, or a non-equilibrium current flowing into a superconductor as disclosed in Patent Document 3 or Non-Patent Document 3 below, and an interband phase difference soliton along with the current. A method has been proposed.
“Soliton in Two-Band Superconductor”, Y. Tanaka, Physical ReviewLetters, Vol.88, Number 1, 017002 “Interband Phase Modes and Nonequilibrium Soliton Structures in Two-Gap Superconductors”, A.Gurevich and VMVinokur, Physical Review Letters, Vol.90, Number 4, 047004

  Similarly, with respect to detection, as disclosed in Patent Documents 1 and 2 and Non-Patent Document 2, a method of detecting the generation of a halfway magnetic flux quantum (Fractional Flux) generated by an interband phase difference soliton, and the above-mentioned non-patent As can be seen in Document 3, the generation of a voltage due to the pair annihilation of the interband phase difference soliton and the antiband phase difference soliton is detected, or, as disclosed in Patent Document 3, the soliton collides with the Josephson junction. A method of generating a voltage by the AC Josephson effect and detecting it is disclosed.

As one utilizing a phase difference of a plurality of superconducting components, a structure in which two thin superconducting layers are stacked as disclosed in Non-Patent Documents 4 and 5 below has been proposed. If the film is thick, the superconducting film confines the magnetic flux between the two superconducting layers, and becomes a fluxon. Smaller than Flaxson. When the effect of magnetic flux is very small, this can be considered the same as the interband phase difference solitons. That is, it is possible to realize a device using a component phase difference soliton that eliminates the involvement of magnetic flux by utilizing the phase difference of a plurality of superconducting components (reduced to a negligible level).
“Magnetic Response of Mesoscopic Superconducting Rings with Two Order Parameters”, Hendrik Bluhm, Nicholas C. Koshnick, Martin E. Huber, and Kathryn A. Moler, Physical Review Letters, Vol. 97, (2006) 237002 “Phase Textures Induced by dc-Current Pair Breaking in Weakly Coupled Multilayer Structures and Two-Gap Superconductors”, A. Gurevich and VM Vinokur, Physical Review Letters, Vol. 97, (2006) 137003

  However, it is very meaningful to create a model to explain the circuit operation in an easy-to-understand manner regardless of whether it is related to fluxon or such interband phase difference solitons. It can also be applied practically.

Actually, as recognized in Non-Patent Documents 6 to 9 below, a model has been devised to assist understanding by visually displaying the circuit operation, although it relates to Fluxon.
“Physics and Applications of Josephson Effect”, A. Barone and G. Paterno, John Wiley & Sons, ISBN-0-471-01469-9, Chapter 10 Fluxson Dynamics P264-271. “A Nonlinear Klein-Gordon Equation”, AC Scott, Am. J. Phys. 37 (1969) 52-61. “Mechanical analogue of active Josephson transmission line”, Koji Nakajima, Tsutomu Yamashita, and Yutaka Onodera, J. Appl. Phys. 45 (1974) 3141-3145. Josephson effect << Fundamentals and Applications >> The Institute of Electrical Engineers of Japan, cryoelectronics permanent edition 1978 (Corona) 3055-007690-2353, especially pages 38-51

  In such a model, all the Sine-Gordon equations are replaced by discrete models. In other words, it is a model in which a plurality of unit cells are arranged and fixed in parallel with an interval between them adjacent to each other in the axial direction of the shaft member (the direction in which the shaft member has a one-dimensional length). In this case, the shaft member is made of an elastic member that stores elastic energy as a restoring force when twisted in the circumferential direction around its central axis, such as a long rubber or coil spring.

  For example, in the model disclosed in Non-Patent Document 6 described above, a long coil spring is used as a shaft member, and a bronze plug is soldered inside the spring at intervals in the axial direction. A nail that is fixed and extends radially from the plug is fixedly provided, and each nail constitutes a unit cell.

  In the initial state (reset state), the coil spring is not twisted, and elastic energy that exhibits a restoring force in the circumferential direction is not stored. In this state, when the coil spring is parallel to the ground surface, the above soldering is performed so that all unit cells hang in the direction of gravity, that is, the vertical direction, and a model is made.

  When one end of the coil spring is fixed and the other end is twisted, the elastic energy increases. Of course, even if the difference in the rotation angle between adjacent cells is 360 degrees, the elastic energy does not return to the initial state of zero, and the elastic energy increases more as it is rotated beyond 360 degrees. to continue. The magnitude of the elastic energy that is stored depends on the absolute value of the difference in rotation angle. If the absolute value of the rotation angle is the same even if rotated in the opposite direction, the same amount of elastic energy is stored.

  On the other hand, since the axial direction (one-dimensional direction) of the model is parallel to the ground, the gravitational energy of the unit cell returns to zero each time it rotates 360 degrees. That is, the gravitational energy has a periodic potential with respect to the rotation angle. The unit cell is also expected to have an inertia moment during rotation.

  These three physical quantities, namely, the elastic energy generated when the shaft member is twisted around the central axis, the gravitational energy applied to the unit cell, and the moment of inertia expected in the unit cell are handled by the sine-Gordon equation. Each parameter is satisfied. Basically, it has an energy structure that monotonously increases with the rotation angle difference between the adjacent unit cell and itself, and a periodic potential structure that returns to zero when it rotates 360 degrees with respect to its own rotation. This is a condition required for a model of a topological soliton circuit. Since the unit cell is a massive tangible object that receives gravity, the moment of inertia is naturally expected. However, it can be said that what kind of functional system is actually not an essential problem when creating a model of a topological soliton.

  Non-Patent Document 6 mentioned above also touches on an example of making a model that is simpler, using a sewing pin (town needle) and a rubber string, and piercing the needle in the length direction of the rubber string. There is also a proposal to make

  However, the model disclosed in Non-Patent Document 6 is not necessarily easy to manufacture. Plugs for fixing the unit cells in the coil springs, placing them one by one carefully, and placing them in place and soldering there are extremely hard work. The work of fixing the cells so that all the unit cells are aligned in one plane including the central axis of the shaft member is also extremely troublesome. The work of piercing the rubber string with the town needle is also very troublesome, and the nerve is used for the work of piercing so that all the town needles are located in one plane. First, the work of using the gusset needle is also dangerous, and when you move the model, you may fly off and get injured. The above-mentioned non-patent documents 7 to 9 also have the same drawbacks, and if an attempt is made to actually make a model, it takes a lot of trouble and tends to increase in size.

  However, what is more problematic is the method of applying the bias when simulating the bias applied to the soliton. In models that cannot simulate bias, solitons will eventually stop. For this reason, in Non-Patent Documents 8 and 9 and the like, a device for blowing wind is attached to each unit cell, thereby simulating a bias. However, such a wind power utilization method considerably increases the size of the apparatus. In fact, a fairly large fan is required. In addition, the setting of the blowing angle for blowing the wind is troublesome, and the reproducibility is difficult. Every time you move the model, you have to move the big fan and set it up again.

  In view of such a conventional situation, the present invention performs a bias application reasonably and reliably without using a large apparatus as a model for explaining the circuit operation of topological solitons such as fluxon and interband phase difference solitons. In addition, it is easy to assemble and disassemble, and it is very easy to reset to the initial state, and if necessary, parameter adjustment and change, for example, adjustment and change of the interval between adjacent unit cells, etc. The purpose is to provide a model that can be used.

In order to achieve the above object, the present invention first has a basic configuration as follows:
It has a length with the one-dimensional direction as the axial direction, and when it is twisted in the circumferential direction around the central axis, it stores elastic energy as a restoring force, and when it is stretched in the axial direction by applying a tensile force in the axial direction A hollow elastic shaft member that reduces the outer diameter radially inward, exhibits a diameter expansion force that is a restoring force radially outward in the reduced state, and also exhibits a restoring force in the axial direction;
A unit cell in which a plurality of the hollow elastic shaft members are detachably fixed at intervals in the axial direction and the center of gravity is located at a position different from the fixing portion with the hollow elastic shaft member;
The hollow elastic shaft member is inserted along the axial direction in the axial direction, has an outer diameter smaller than the inner diameter of the hollow elastic shaft member, and in the posture in which the hollow elastic shaft member is parallel to the ground, the upper part of the outer peripheral surface in the vertical direction A shaft member for rotation driving that contacts the inner peripheral surface of the hollow elastic shaft member at the position and transmits the rotation driving force to the hollow elastic shaft member through frictional force at the contact portion when receiving rotational driving;
A rotational drive mechanism capable of controlling the rotational speed for rotating the rotational drive shaft member;
We propose a model of topological soliton circuit.

  In addition to the basic configuration described above, the contact portion between the outer peripheral surface of the rotary drive shaft member and the inner peripheral surface of the hollow elastic shaft member is substantially point contact by contacting only at a portion where the unit cell is fixed. Also proposed is the configuration. For this purpose, the following configuration can be proposed.

  That is, each unit cell has a through hole that penetrates the hollow elastic shaft member in the fixed portion, and the inner diameter of the through hole is larger than the outer diameter when the tensile force is not applied to the hollow elastic shaft member. The unit cell is fixed to the hollow elastic shaft member by the above-described radial outward expansion force that is exhibited when the hollow elastic shaft member is radially reduced in the through hole. When a tensile force is applied to the elastic shaft member, the outer diameter of the hollow elastic shaft member is reduced to a smaller diameter than the inner diameter of the through hole, so that the unit cell is fixed, and the unit cell is fixed to the hollow elastic shaft member. When the unit cell is fixed to the hollow elastic shaft member at the fixed portion, the hollow elastic shaft member at the fixed portion has a radius. Bending inward Therefore, the inner diameter of the hollow elastic shaft member at the bent portion is smaller than the inner diameter of the portion where the unit cell is not fixed. A model configured to come into contact with the outer peripheral surface can be proposed.

  On the other hand, the rotational drive shaft member may be provided halfway along the length of the hollow elastic shaft member. This can simulate a state in which a bias is applied to the middle of the hollow elastic shaft member.

  In addition, not only when the rotational drive shaft member is only halfway through the length of the hollow elastic shaft member as described above, but also when it is longer than the hollow elastic shaft member so as to pass through the entire length of the hollow elastic shaft member, The rotational drive shaft member itself can also be hollowed, and a model support support shaft member can be passed in the axial direction without impeding the rotation of the rotational drive shaft member.

  Further, as a subordinate aspect of the present invention, the rotation drive mechanism capable of controlling the rotation speed can be simply configured by a motor driven by electric power, and as is well known, such a motor can be rotated by variable adjustment of voltage or current. The number can be easily controlled. Even if a transmission, preferably a continuously variable transmission, is interposed between the rotational drive mechanism and the rotational drive shaft member, the rotational speed of the rotational drive shaft member can be controlled. The hollow elastic shaft member may be a rubber hose or a coil spring, and the unit cell may be a sheet-like member. You may be comprised from the hole-shaped member and the rod-shaped member extended from a part of this through-hole formed member. However, the shape of the unit cell is almost free as long as it satisfies the requirements defined by the above basic configuration.

  Further, a part of the outline of the through hole of the unit cell is connected to a slit opened toward the peripheral edge of the unit cell, and the shaft member can be fitted into the through hole in the radial direction via the slit. A possible configuration can also be proposed.

  Furthermore, the inner peripheral edge of the through hole of the unit cell may be provided with a protrusion that protrudes inward in the radial direction and engages with the outer peripheral surface of the shaft member, and the unit cell is along a dividing line that passes through the through hole. Can be divided into at least two parts, and these two parts can be assembled with each other via a snap-engaging fastener structure to form a through-hole, and can be detached from the shaft member by releasing the snap-engagement. It may be.

  From a point of view different from these configurations, as a configuration suitable for observing the behavior of soliton shape change and line impedance change, at least some of the unit cells are provided with weights that can be selectively fitted. May be.

  According to the present invention, when a model of a topological soliton circuit that needs to simulate a bias is provided, a large-scale device is not required to simulate the bias. As before, there is only an image as a completely separate device from the model, and there is no need for a fan that is large and troublesome to install and set up. It is almost integrated with the model and is extremely small and easy to assemble. In addition, it can be a model with a built-in bias application device that also operates reliably.

  Moreover, since the bias is applied to the soliton by skillfully using the frictional force accompanied by the slip at the contact portion between the inner peripheral surface of the hollow elastic shaft member and the outer peripheral surface of the rotary drive shaft member, the rotational speed of the rotary drive mechanism is reduced. By appropriately adjusting on the spot, the bias that leads to the running force can be applied in a good manner only to the soliton without rotating the hollow elastic shaft member as a whole. In particular, according to a specific aspect of the present invention, the outer peripheral surface of the rotary drive shaft member is in contact only with the inner peripheral surface of the portion where the unit cell is fixed and the hollow elastic shaft member is bent radially inward. In other words, by making a set of contact portions in a state that is substantially close to a point contact, the controllability is further improved.

  Further, in order to achieve a contact that can be recognized as a substantially point contact between the hollow elastic shaft member and the rotary drive shaft member at the fixed portion of the unit cell as described above, a specific aspect of the present invention as described above is used. This also provides a model of a topological soliton circuit that is extremely easy to assemble and disassemble. Restoration (reset) to the initial state in which the center of gravity of all the unit cells should be aligned vertically downward when viewed from the fixed portion with the shaft member is completely simplified and can be performed almost instantaneously.

  That is, if the diameter of the shaft member is reduced while pulling in the axial direction, the outer diameter of the reduced diameter shaft member can be smaller than the inner diameter of the through-hole of the unit cell. The members can be easily passed, and the operation of shifting each unit cell in the axial direction in order to adjust the interval between the unit cells is extremely simple. If the pulling force of the shaft member is released, the shaft member expands toward the original diameter by the restoring force in the radial direction of the shaft member itself, and becomes sufficiently larger than the inner diameter of the through hole. The unit cell is fixed to the shaft member by the radial force. It is self-evident that the disassembly is easy, and it is only necessary to pull out the unit cell sequentially in the axial direction by pulling the shaft member.

  Similarly, after the model is operated, all the unit cells do not return to the initial state where they are hung downward in the vertical direction. If the shaft member is pulled in the axial direction to reduce the diameter, the shaft member and the unit cell are temporarily fixed, the unit cell escapes from the restraint due to the radial expansion force of the shaft member, and rotates in the circumferential direction by its own weight. It is easily reset so that the center of gravity is directed vertically.

  In addition, it is easy to adjust the interval after assembly of the unit cell to the shaft member, and if the shaft member part near the unit cell is pulled to reduce the diameter, the unit cell can move freely in the axial direction, so that The position can be easily fine-tuned.

  According to a specific aspect of the present invention, among the plurality of unit cells fixed to the shaft member, at least one unit cell fixed at least at a predetermined axial position is selectively weighted, and at least some By changing the moment of inertia of each unit cell, it is possible to easily observe the behavior of solitons in a non-uniform propagation line, such as a change in line impedance.

  In summary, according to the present invention, the operation and function of the topological soliton circuit can be understood intuitively, and as a model useful for circuit design, a pattern with a bias applied can be simulated without requiring a large incidental device. Therefore, a suitable model can be provided. In addition, it is easy to assemble and disassemble, and can provide extremely useful models that can easily change parameters, including non-uniformity of space, and can be used in many educational settings outside research institutions. It will be a thing. There is a small number of parts, including parts necessary for bias simulation, and it is based on a structural principle that can provide an inexpensive product.

  FIG. 1 shows a preferred embodiment to which the present invention is applied as a model of a topological soliton circuit. First, as a necessary component element, there is a hollow elastic shaft member 11 having a length with a one-dimensional direction as an axial direction, which stores elastic energy as a restoring force when twisted in the circumferential direction around the central axis. . When the hollow elastic shaft member 11 is extended in the axial direction by applying a tensile force Ft in the axial direction, as shown in FIGS. The outer diameter in a steady state shown in FIG. 3B, that is, the outer diameter φn when the tensile force Ft is not applied is reduced radially inward to a diameter φs (<φn). In such a reduced diameter state, it exhibits a radially outward expansion force that is a restoring force to return to the original steady-state outer diameter φn, and also restores to return to the original length in the axial direction. Shows power. Examples of such a hollow elastic shaft member 11 that are easily available and inexpensive include, but are not limited to, a rubber hose (rubber tube) made of an appropriate material.

  Next, an important component element is a unit cell 12, and this unit cell 12 is detachably fixed to a plurality of 12 .... while being spaced from each other along the axial direction of the hollow elastic shaft member 11, There is a position of the center of gravity at a position different from the fixed portion 21 fixed to the hollow elastic shaft member 11.

  The unit cell 12 in the illustrated embodiment is, as an example of a configuration that is easy to manufacture, a sheet-like member, in particular, a strip-like shape made of rectangular cardboard, and a position 21 that deviates from the diagonal intersection of the rectangle becomes the fixing portion 21. Here, by being fixed to the hollow elastic shaft member 11, the center of gravity is located at a position different from the fixing portion 21. In this embodiment, as will be described later, the fixing portion 21 includes a through-hole 13 (FIG. 3) opened in the unit cell 12 and a through-hole in a state where no axial tensile force Ft is applied. The inner diameter φc of 13 is substantially constituted by the elastic engagement relationship with the hollow elastic shaft member 11 having a larger steady diameter φn.

  Further, as a necessary component element, there is a rotational drive shaft member 51 inserted in the hollow portion of the hollow elastic shaft member 11 in the axial direction. In the case shown in the figure, the rotational drive shaft member 51 is longer than the hollow elastic shaft member 11, passes through the hollow elastic shaft member 11, and has a general motor as a rotational drive mechanism 52 at one end in the axial direction. The other end of the rotary shaft 52 connected to the hollow elastic shaft member 11 is rotatably supported by a bearing 54 such as a bearing bearing, which preferably has as little rotational frictional force as possible. However, if stated in advance, the rotational drive mechanism 52 that rotationally drives the rotational drive shaft member 51 as needed can adopt any known structure in the mechanical system and can control the rotational speed. There is no principle limitation.

  However, if you select the most commonly considered power drive type motor 52 as the rotation drive mechanism 52, it is convenient because it can easily and reliably control the rotation speed with considerable accuracy by variable adjustment of the applied voltage or current. is there. Although the motor is used also in the experiment of the present inventors, the electric power applied to the motor 52 becomes variable by the model operator turning the knob attached to the rotation speed control device 53, so that the motor rotation speed is different. Such devices are very readily available. However, this is not restrictive, and the device may be a device that adjusts the rotational speed by changing the amount of electricity, for example, via a transmission, preferably a continuously variable transmission.

  As shown in FIG. 3 (B), the rotational drive shaft member 51 used in the present invention has an outer diameter φr smaller than the inner diameter φi of the hollow elastic shaft member 11, and preferably FIG. As shown in (D), the outer diameter of the hollow elastic shaft member 11 is smaller than that of the hollow elastic shaft member 11 when the outer diameter is reduced to φs at the time of assembling this model, which will be described later, or at the time of resetting the unit cell. The meaning of this will be described later.

  FIG. 1 (A) shows the initial state of the model. When the hollow elastic shaft member 11 is placed in a posture parallel to the ground, the plurality of unit cells 12 are all viewed from the fixed portion 21 in the position of the center of gravity. The hanging postures are aligned so as to be vertically downward (gravity direction).

  In the case of this embodiment, the hollow elastic shaft member 11 is simply placed on the rotational drive shaft member 51, and both ends in the axial direction, that is, the first free end 11fa on the front side of the drawing are also connected to the shaft. The second free ends 11fb that face each other in the direction are not positively fixed together, and can be slidably rotated in the circumferential direction with respect to the rotation drive shaft member 51, but the rotation drive shaft member A so-called temporary fixed relationship is established by the frictional force between the outer peripheral surface of 51 and its own inner peripheral surface.

  However, first, without rotating the rotational drive shaft member 51, the first free end 11fa of the hollow elastic shaft member 11 is, for example, as shown by an imaginary line arrow Fr in FIG. Let's say you twisted from about 360 degrees. Then, the unit cells 12 are rotated one by one in order from the front, and the state of rotation is propagated toward the second free end 11fb, which generates topological solitons. It is a simulation of how it propagates through the transmission line.

  For example, if an image viewed from the side is taken with a certain time width, it is as shown in FIG. 2 (A). When a sine wave or mountain is shown, the first free end twisted in the direction of the arrow Fr. It is observed that the pattern proceeds on the hollow elastic shaft member 11 along the direction Ff from the 11fa side toward the second free end 11fb at the other end. The part corresponding to this mountain is the topological soliton So, and the axial distance from the foot to the foot of this mountain is the length of the topological soliton So.

  If the initial torsional force is large, the topological soliton So has a relationship such that the topological soliton So is temporarily fixed by the frictional force by riding on the rotational drive shaft member 51 as shown in FIG. 2 (B). When it reaches a certain second free end 11fb, it is reflected there, and as indicated by the arrow Fb, it also moves back toward the first free end 11fa. FIG. 2 (C) schematically shows a front view of each unit cell 12 that rotates 360 degrees in the same rotation direction Fr along with the twist of the hollow elastic shaft member 11, and the rotation angle position P0 is in an initial state, that is, fixed. The position of the center of gravity is aligned in the vertical direction when viewed from the portion 21, and from there, the rotation angle positions P1, P2,..., P7 are reached again to return to the initial position P0.

  That is, as described above, even if the difference in the rotation angle between adjacent cells is 360 degrees, the elastic energy of the hollow elastic shaft member 11 does not return to the zero state. As the number of rotations further increases, the elastic energy continues to increase, but the gravitational energy of the unit cell 12 returns to zero each time it rotates 360 degrees. In the model of the present invention, this state is realized by a model having an extremely small number of parts, and the behavior of the topological soliton can be visualized.

  Furthermore, the present invention is characteristically that the bias can be reasonably and reliably simulated with a simple structure. That is, as described above, first, the hollow elastic shaft member 11 is slightly twisted in the direction of the arrow Fr to generate the topological soliton So. However, if nothing is done as it is, the topological soliton So will eventually stop.

  Therefore, as shown in FIGS. 1B and 2B, the motor 52 in this case, which is the rotation drive mechanism 52, is rotated, and the rotation elastic shaft member 51 is twisted to rotate the hollow elastic shaft member 11. When the rotation is performed in the same direction as the direction Fr as indicated by the arrow Fm, the generated topological soliton So can be continued without stopping by appropriately controlling the rotation speed. That is, it simulates a bias. Moreover, the configuration is much simpler than the case where a separate electric fan is prepared as before, and the reliability with respect to the rotational drive is remarkably high. It can be said that the model is fully covered as a model.

  The degree of bias application can be arbitrarily set on the spot.For example, when the rotational drive mechanism 52 starts to rotate slowly and the hollow elastic shaft member 11 does not rotate as a whole, only the topological soliton So begins to advance. It can be set as the base point state. If the bias is increased, that is, if the rotational speed of the rotational drive mechanism 52 is increased, the soliton So can be advanced quickly, and if it is rotated in the reverse direction, it can be observed that it moves backward.

  Here, in a sense, a subtle bias application relationship, that is, a rotational drive force transmission relationship, can be realized very skillfully, for example, according to the following configuration. This can simplify the assembly and disassembly of the model and the topological soliton So. It is possible to contribute to a simple reset. 3B again, the outer diameter φr of the rotary drive shaft member 51 is smaller than the inner diameter φi of the hollow elastic shaft member 11 when the outer diameter is the steady diameter φn. As a result, the hollow elastic shaft member 11 should be in a relationship of being freely rotatable outside the rotation drive shaft member 51. However, since there is gravity, when both shaft members 11 and 51 are in a posture parallel to the ground, the contact position between them is the position of the upper part in the vertical direction on the outer peripheral surface of the rotary drive shaft member 51, that is, the gravity. A surface portion extending linearly in the axial direction at the highest position in the direction opposite to the application direction, and a surface portion extending linearly at the position on the inner peripheral surface of the hollow elastic shaft member 11 and in the same vertical direction And are in linear contact with each other along the axial direction. This is a contact with frictional force that produces moderate slip.

  If this contact is a contact that is point-to-point and substantially point-to-point when viewed in the axial direction, the rotational force of the rotational drive shaft member 51 is appropriately and well transmitted to the hollow elastic shaft member 11. desirable. Therefore, in this embodiment, the following devices are devised. That is, since the stationary diameter φn of the hollow elastic shaft member 11 is thicker than the inner diameter φc of the through-hole 13 opened in the unit cell 12, the portion where each unit cell 12 is fixed is schematically shown in FIG. As is well shown, the portion of the hollow elastic shaft member 11 is pushed radially inward, where the inner diameter is further narrower than the steady inner diameter φi so that it is substantially rotated. The driving shaft member 51 and the hollow elastic shaft member 11 come into contact with each other as viewed in the axial direction only at a portion Pc where the hollow elastic shaft member 11 is bent inward in the radial direction. That is, the above-described linear contact extending in the axial direction further changes to a contact relationship in which contact portions Pc that can be regarded as point contacts are arranged at intervals in the axial direction.

  If the diameter relationship is appropriately selected in this way, the bias can be simulated very well. The portion of the topological soliton So, that is, the unit cell 12 facing downward in the vertical direction, is rotated by the rotation of the motor 52 by the rotation of the motor 52 due to its own weight and the frictional force at the point contact portion Pc. However, the unit cell 12 in the topological soliton So part that has already rotated is the center of gravity as viewed from the fixed part 21, while maintaining the state of hanging from the hollow elastic shaft member 11 as it is without causing rotation. As a result of the position deviating from the downward direction in the vertical direction and the vertical vector component of the gravitational energy being reduced, an appropriate rotational drive is performed from the rotational drive shaft member 51 via the frictional force accompanied by the slip at the point contact portion Pc. As a result, you can see how the topological soliton So continues to run stably.

  When viewed in the radial direction, the second free end 11fb is not shown in the both ends of the hollow elastic shaft member 11 riding on the rotation drive shaft member 51, but it is intentionally made non-rotatable by appropriate gripping means. When fixed, this also simulates the memory mechanism of the topological soliton So even when a bias is applied. That is, even if the topological soliton So travels while being applied with a bias, it stops at the second free end 11fb, and the topological solitons So that are rotated one after another accumulate here.

  Further, assuming that the rotational drive shaft member 51 is halfway in the length of the hollow elastic shaft member 11, it is possible to simulate the case where a bias is applied only to the middle portion. In this case, the support of the second free end 11fb of the hollow elastic shaft member 11 is considered separately. For example, if the rotation drive shaft member 51 itself is a hollow hollow pipe, it is not shown in the figure. If a highly rigid shaft member is inserted as a model support shaft member and the rotation drive shaft member 51 is supported so as not to impair rotation, the entire model can be stably supported.

  As described above, the bias application to the topological soliton So, which is one of the major features of the present invention, has been described. In addition, in this embodiment, as described below, assembling and disassembling, and parameter adjustment and change are performed. However, the structure can be performed very easily.

  3D again, in the present invention, the inner diameter φc of the through hole 13 of the unit cell 12 is smaller than the steady diameter φn when the tensile force Ft is not applied to the hollow elastic shaft member 11. I understand that. Therefore, as shown in FIG. 5B, in the assembled state, the hollow elastic shaft member 11 is forcibly pressed and narrowed in the radial direction in the through-hole 13 of the unit cell 12, and the inner diameter in the steady state described above. Since the diameter is further reduced from φi, the unit cell 12 is fixed to the hollow elastic shaft member 11 by the radially outward expansion force that is the elastic repulsion force. That is, the inner peripheral surface of the through-hole 13 of the unit cell 12 looks as if it bites the outer peripheral surface of the hollow elastic shaft member 11, thereby preventing relative rotation between the hollow elastic shaft member 11 and the unit cell 12, When the hollow elastic shaft member 11 is twisted and rotated, the structure in which the unit cell 12 is also stably rotated is realized. Thus, as described above, the diameter relationship φc <φn is that the rotational driving force from the rotational driving shaft member 51 is applied to the hollow elastic shaft member 11 and thus to the unit cell 12 via the frictional force with appropriate slippage. This is not only a good idea to convey well, but also a relationship useful for easily fixing the unit cell 12 to the hollow elastic shaft member 11.

  On the other hand, as shown in FIGS. 3 (C) and 3 (D), when a tensile force Ft is applied to the hollow elastic shaft member 11, the hollow elastic shaft member 11 having elasticity in the axial direction also has a through hole. The inner diameter φc of 13 can be reduced to a smaller diameter φs. When this happens, the fitting relationship between the hollow elastic shaft member 11 and the through-holes 13 of the unit cell becomes a so-called “buzzy” state, so that the fixing of the unit cell 12 is released, and the unit cell 12 is released from the hollow elastic shaft member 11. It can move both axially and circumferentially.

  What this means is that it is very easy to assemble and disassemble the model and to reset the model to its initial state after operating the model. For example, first, the hollow elastic shaft member 11 is reduced in diameter while being pulled in the axial direction, and the reduced diameter of the shaft member outer diameter φs at that time is smaller than the through hole inner diameter φc of the unit cell 12. The hollow elastic shaft member 11 can be easily passed through 13, and the assembling work in which a large number of unit cells 12 are fixed to the hollow elastic shaft member 11 is remarkably simplified.

  The operation of shifting each unit cell 12 in the axial direction in order to adjust the interval between adjacent unit cells 12 is extremely simple. That is, for the time being, after all the unit cells 12 are passed through the hollow elastic shaft member 11, the operation of shifting all the unit cells 12 to the respective predetermined positions while pulling the hollow elastic shaft member 11 is performed on the hollow elastic shaft member 11 side. Because it does not receive any resistance from, it can be done very smoothly.

  However, if one end of the hollow elastic shaft member 11 is kept in a state of being sufficiently reduced in diameter by being wound with a tape or the like even at the time of assembly, the unit cells 12 are sequentially hollowed out through the through-holes 13 in this manner. The work going through the shaft member 11 is more advanced.

  If the tensile force of the hollow elastic shaft member 11 is released after all the unit cells 12 are attached to the target positions, the hollow elastic shaft member 11 is directed toward the steady diameter φn by the restoring force in the radial direction of the shaft member itself. The diameter of the unit cell 12 is sufficiently larger than the inner diameter φc of the through hole. Therefore, as already described with reference to FIG. Fixed. Therefore, it will be obvious that the reverse operation and the disassembly are simple. The hollow elastic shaft member 11 may be pulled and the unit cells 12 may be sequentially pulled out in the axial direction.

  In addition, the initial state of all unit cells 12 so that the center of gravity of all unit cells 12 is aligned in the vertical direction when viewed from the fixed portion 21 is only one time. For the time being, after the unit cell 12 is fitted to the hollow elastic shaft member 11 or after the model is operated as described above, the unit cell 12 may not be in the initial state where it is suspended vertically. is there. As shown in FIG. 3 (A), some unit cells 12 may remain stationary while being twisted. However, according to the model of the present invention, the hollow elastic shaft member 11 and the unit cell 12 can be unfixed simply by pulling the hollow elastic shaft member 11 in the axial direction to reduce the diameter. Can be easily set or reset so as to rotate in the circumferential direction and direct its center of gravity in the vertical direction.

  This effect is extremely large. There is no doubt that the present invention is superior to the conventional example described above as compared to the case where the assembly is remarkably troublesome, the reset to the initial state is troublesome, or parts that may cause injury such as gusset needles are used. . In particular, if the hollow elastic shaft member 11 is simply pulled in the axial direction, the skill of resetting it to the initial state with that is no more convenient.

  Incidentally, in the experiment of the present inventor, an elastic tube having an outer diameter φn of 7 mm and an inner diameter φi of 5 mm was used as the hollow elastic shaft member 11. Specifically, it is the product name “Unitube” related to the sales of Nippon Riken Kikai Co., Ltd. located in Koraku, Bunkyo-ku, Tokyo. As the unit cell 12, a strip having a length of 9 cm and a width of 3 cm was made of thick paper, and a through-hole 13 having an inner diameter φc of 6 mm was formed at a position about 1 cm inward from one short side of the strip. When the elastic tube was pulled, its outer diameter could be reduced to a state thinner than the inner diameter of 6 mm of the through hole 13, and the unit cell 12 could be easily assembled and moved in the axial direction. In addition, even after the model was operated, all the strips 12 were easily reset by simply pulling the elastic tube. About 200 strips were made. Further, an aluminum pipe having an outer diameter φr of 3 mm was used as the rotational drive shaft member 51 inserted in the elastic tube in the axial direction.

  However, the unit cell 12 need not be limited other than that limited by the gist of the present invention. The fixing portion 21 with the hollow elastic shaft member 11 has a through-hole 13 that penetrates the hollow elastic shaft member 11, has a center of gravity position at a position different from the position where the through-hole 13 is located, and the inner diameter of the through-hole 13 As long as φc is smaller than the steady diameter φn of the hollow elastic shaft member 11, it may be any other shape including a circular shape. Even if it is circular, the requirement of the present invention is satisfied if the through-hole 13 is removed from the center.

  Some convenient modifications to the unit cell 12 itself can be proposed. For example, as shown in FIG. 4A, the hollow elastic shaft member 11 protrudes radially inward from the inner peripheral edge of the through hole 13 of the unit cell 12. When the protrusion 14 that engages with the outer peripheral surface of the hollow elastic shaft member 11 is provided, the fixing force between the hollow elastic shaft member 11 and the unit cell 12 when the hollow elastic shaft member 11 is at the steady diameter φn can be further increased. Of course, when the hollow elastic shaft member 11 is pulled, the hollow elastic shaft member 11 is required to be elastic so that the diameter φs of the reduced diameter is sufficient to clear the protrusions 14 without being broken.

  Further, as shown in FIGS. 4B to 4E, a part of the outline of the through-hole 13 of the unit cell 12 is connected to the slit 15 opened toward the peripheral edge of the unit cell 12, and this The hollow elastic shaft member 11 may be fitted into the through hole 13 in the radial direction via the slit 15 so that the assembly can be easily performed. Also in this case, the effect of the present invention in which all the unit cells 12 can be easily reset by pulling the hollow elastic shaft member 11 can be similarly enjoyed.

  Of course, it is necessary to keep the opening width of the slit 15 at a width that does not come off the hollow elastic shaft member 11 even if the hollow elastic shaft member 11 is pulled to reduce the diameter for resetting. The slit shape is also arbitrarily arbitrary. Especially, as shown in FIGS. 4 (D) and 4 (E), if the mouth is opened on the taper, the fitting operation of the hollow elastic shaft member 11 is easier. Become.

  The material of the unit cell 12 is cardboard in the experimental examples described above, but is not limited to this, and the material may be plastic, wood, or in some cases metal. In particular, when it is made of plastic, a convenient structure as shown in FIGS. 5A and 5B can be proposed. In the field of so-called plastic fasteners, an easily attachable / detachable fastener structure has been proposed, and this is used to divide the unit cell 12 into at least two parts 12a and 12b along a dividing line passing through the through hole 13. These two portions 12a and 12b can be assembled to each other by snap engagement in the fastener structure 16 to form a through hole 13 so that it can be assembled to the hollow elastic shaft member 11, while releasing the snap engagement. For example, the hollow elastic shaft member 11 may be easily removed.

  Thus, using the unit cell 12 that can be attached to the hollow elastic shaft member 11 by so-called lateral fitting operation may be more convenient to increase the degree of freedom of parameters. Basically, in the model of the present invention, it is possible to easily create a state in which the unit cell interval is partially short while the hollow elastic shaft member 11 is pulled, so that the behavior of topological solitons in a non-uniform propagation line is seen. In addition to this, if the unit cell 12 having a structure as shown in FIGS. 4 (B) to 4 (D), 5 (A) and 5 (B), which is easy to assemble and remove, is used. It is also possible to prepare multiple types of different lengths in advance and experiment with all or part of them as necessary. Using short unit cells and unit cells with a small moment of inertia, topological It can be observed that the length of the soliton So is shortened.

  As for the shape change, as shown in FIG. 6, the unit cell 12 has a circular or arc-shaped through-hole forming member 12c forming the outline of the through-hole 13, and a rod-like shape extending from a part of the through-hole forming member 12c. It may be configured of the member 12d. Such a structure is generally suitable for making light unit cells. Further, in the illustrated case, the slit 15 is also formed in a part of the through hole forming member 12c, and can be fitted in the radial direction. As shown in FIG. 4 (A), it is naturally possible to further provide the slit 15 even in the structure in which the protrusion 14 is provided on the inner peripheral edge of the through hole 13 of the unit cell 12.

  The hollow elastic shaft member 11 can be a rubber spring, a coil spring, or the like, and can be used as long as it is a hollow elastic body exhibiting a Poisson effect in which a longitudinal strain produces a lateral strain. It can be used as the member 11. Even in these cases, it is possible to obtain an appropriate rotational frictional force with the rotational drive shaft member 51 passing through the hollow interior.

  As a preferred configuration for using the model of the present invention to see the behavior of changes in topological soliton shape and line impedance, as shown in FIG. 7, at least some of the unit cells 12 are selective. You may make it provide the weight 17 which can be fitted in. Depending on the weight of the weight 17 and how many unit cells 12 are continuously provided with weights, the reflection path indicated by the arrow Ff to the arrow Fb is normally indicated by the arrows Ff ′ and Fb ′. Thus, after a certain part of the unit cell 12 with the weight, even if a bias is applied, it is not possible to proceed, and the state of reflection and return can be clearly shown. Or, conversely, overcoming this barrier can be simulated depending on the magnitude of the bias.

  As mentioned above, although this invention was demonstrated according to embodiment, as long as it corresponds to the summary structure of this invention, arbitrary modification | changes are free. In any case, according to the present invention, it becomes very easy to create a model for visualizing a soliton circuit and intuitively grasping its function, and in particular, the spatial dynamics of topological soliton dynamics in a one-dimensional propagation path. The parameters can be easily changed including the aspect. Above all, the bias application to the topological soliton can be rationally simulated by a simple and reliable configuration even when assembled.

It is a schematic block diagram in desirable one Embodiment of the topological soliton circuit model of this invention. It is explanatory drawing regarding the basic operation | movement of this invention model. It is explanatory drawing regarding the fixed relationship of the shaft member and unit cell of this invention model. It is explanatory drawing regarding the modification of the unit cell of this invention model. It is explanatory drawing of the other modification regarding the unit cell of this invention model. It is explanatory drawing of the further another modification regarding the unit cell of this invention model. It is explanatory drawing regarding other embodiment of this invention model, and its operation example.

Explanation of symbols

11 Hollow elastic shaft member
12 unit cells
13 Through hole
14 Protrusion in the through hole
15 slit
16 Fastener structure
17 weights
21 Hollow elastic shaft member and unit cell fixing part
51 Rotating drive shaft member
52 Rotation drive mechanism (motor)
53 Speed controller
54 Bearing
So topological solitons

Claims (6)

It has a length with the one-dimensional direction as the axial direction, and when it is twisted in the circumferential direction around the central axis, it stores elastic energy as a restoring force and is stretched in the axial direction by applying a tensile force in the axial direction. And a hollow elastic shaft member that exhibits a diameter expansion force that is a restoring force radially outward in the reduced diameter state and a restoring force also in the axial direction. When;
A unit cell in which a plurality of hollow elastic shaft members are detachably fixed at intervals in the axial direction, and the center of gravity is located at a position different from the fixing portion with the hollow elastic shaft member;
The hollow elastic shaft member is inserted along the axial direction and has an outer diameter smaller than the inner diameter of the hollow elastic shaft member. For the rotational drive that contacts the inner peripheral surface of the hollow elastic shaft member at the upper position in the vertical direction and transmits the rotational driving force to the hollow elastic shaft member via the frictional force at the contact portion when the rotational drive is received. A shaft member;
A rotational drive mechanism capable of controlling the rotational speed for rotating the rotational drive shaft member;
A model of a topological soliton circuit comprising: A model of a topological soliton circuit according to claim 1;
The contact portion between the outer peripheral surface of the rotary drive shaft member and the inner peripheral surface of the hollow elastic shaft member is in contact only with a portion where the unit cell is fixed;
A model of a topological soliton circuit characterized by A model of a topological soliton circuit according to claim 2;
Each of the unit cells has a through hole penetrating the hollow elastic shaft member in the fixing portion, and the inner diameter of the through hole is smaller than the outer diameter when the tensile force is not applied to the hollow elastic shaft member. Thus, the unit cell is fixed to the hollow elastic shaft member by the radially expanding force exerted when the hollow elastic shaft member is radially reduced in the through hole. on the other hand;
When the tensile force is applied to the hollow elastic shaft member, the outer diameter of the hollow elastic shaft member is reduced to a diameter smaller than the inner diameter of the through hole, so that the unit cell is fixed, and the unit cell is Configured to be able to move axially and circumferentially relative to the hollow elastic shaft member;
When the unit cell is fixed to the hollow elastic shaft member at the fixed portion, the hollow elastic shaft member at the fixed portion is bent inward in the radial direction and the hollow elastic shaft at the bent portion. As a result of the inner diameter of the member being smaller than the inner diameter of the portion where the unit cell is not fixed, only the bent inner peripheral surface portion is in contact with the outer peripheral surface of the rotary drive shaft member. is being done;
A model of a topological soliton circuit characterized by A model of a topological soliton circuit according to claim 1;
The rotational drive shaft member is provided partway along the length of the hollow elastic shaft member;
A model of a topological soliton circuit characterized by A model of a topological soliton circuit according to claim 1;
The rotary drive shaft member itself is also hollow inside, and the support shaft member for supporting the model passes through the internal hollow portion of the rotary drive shaft member in the axial direction without hindering the rotation of the rotary drive shaft member. What;
A model of a topological soliton circuit characterized by A model of a topological soliton circuit according to claim 1;
The rotational drive mechanism capable of controlling the rotational speed is a motor driven by electric power;
A model of a topological soliton circuit characterized by

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