JP2019041459A - Article holding device - Google Patents

Abstract

To provide an article holding device capable of effectively utilizing an actuator containing polyrotaxane.SOLUTION: A grip 20 includes: a sheet-like dielectric layer 31 containing cross-linked polyrotaxane; and a pair of electrodes 32, 33 formed on both surfaces of the dielectric layer 31. A power supply 14 is provided that applies a DC voltage between the pair of electrodes 32, 33. An electronic controller 17 selectively switches an operation state of the power supply 14 to one of a "first operation state" in which the grip 20 is adapted to hold an article by increasing the DC voltage applied to the pair of electrodes 32, 33 to bend the grip 20 and a "second operation state" in which the grip 20 is adapted to separate the article by decreasing the DC voltage applied to the pair of electrodes 32, 33 to restore the previous state before the grip 20 is bent.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an article gripping apparatus that grips an article using a crosslinked polyrotaxane.

  A polyrotaxane is composed of a linear molecule, a plurality of cyclic molecules that are slidably inserted into the linear molecule, and a cyclic molecule that is arranged at the end of the linear molecule and is formed from the linear molecule. It is a composition (so-called slide ring material) containing a blocking group that suppresses elimination.

  An actuator using a polyrotaxane is known (see Patent Document 1). This actuator has a sheet-like dielectric layer containing a polyrotaxane crosslinked via cyclic molecules, and a pair of electrodes formed on both surfaces of the dielectric layer so as to sandwich the dielectric layer therebetween.

  This actuator operates by utilizing an attractive force between electrodes that is generated when a voltage is applied between a pair of electrodes. Specifically, when a voltage is applied between the pair of electrodes, the actuator is compressed in the thickness direction and extended in the in-plane direction due to the attractive force between the electrodes that accompanies this. On the other hand, when the voltage application between the pair of electrodes is stopped, the actuator is restored to the original state by the disappearance of the inter-electrode attractive force (specifically, the actuator expands in the thickness direction and contracts in the in-plane direction). )

JP 2017-66318 A

The actuator using the polyrotaxane described above has many characteristics that have not yet been clarified, and research on the actuator is being pursued and an effective utilization method is being sought.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide an article gripping apparatus that can effectively use an actuator containing a polyrotaxane.

  An article gripping apparatus for solving the above problems includes a sheet-like dielectric layer containing a crosslinked polyrotaxane, and a pair of bending-deformable electrodes formed on both surfaces of the dielectric layer so as to sandwich the dielectric layer therebetween A power supply unit that is connected to at least one of the pair of electrodes and applies a potential difference between the pair of electrodes, and an operating state of the power supply unit between the pair of electrodes. A first operating state in which the grip grips the article by increasing the potential difference applied to the grip, and before the grip is bent by decreasing the potential difference applied between the pair of electrodes. There is a switching unit that selectively switches to one of the second operating states in which the grip releases the article by restoring the state.

  The grip is bent by increasing the potential difference applied between the pair of electrodes (for example, applying a potential difference between the electrodes), while reducing the potential difference applied between the pair of electrodes ( For example, it has been discovered that it has a characteristic of being restored (returned to a state before bending) by stopping application of a potential difference between electrodes. In the above configuration, by utilizing such characteristics, the potential difference is increased (applied) and the grip is bent so as to wrap the article, or the potential difference is decreased (the application of the potential difference is stopped) before the grip is bent. By restoring the state, the article once grasped from the grip can be released. Thus, according to the said structure, the actuator containing a polyrotaxane can be used effectively in the apparatus which hold | grips an article | item.

In the above apparatus, one electrode of the pair of electrodes can be connected to the positive electrode of the power supply unit and the other electrode can be grounded.
In the above apparatus, the pair of electrodes includes one electrode connected to the power supply unit and the other electrode, and the grip is an auxiliary electrode that can be bent and deformed at the same potential as the other electrode. However, it is preferable that the dielectric layer is formed at a position spaced apart from the one electrode on one side of the dielectric layer.

  According to the above configuration, when an article comes into contact with the surface of the grip where one electrode and the auxiliary electrode (the same potential as the other electrode) are formed, with the potential difference between the pair of electrodes being increased, The electrostatic attraction force can be generated in a manner of being attracted to the grip. Therefore, since the electrostatic attraction force acting between the grip and the article can be used as the force for grasping the article, in addition to the grasping force by the bent grip, the article can be suitably grasped. become.

  In the above device, on one of both surfaces of the dielectric layer, the one electrode and the auxiliary electrode may be arranged in a comb shape, and the teeth in the comb shape may be arranged alternately. preferable.

  According to the above configuration, by disposing the comb-like electrode, the portion where the electrodes (one electrode and the auxiliary electrode) having different potentials are arranged at intervals, that is, the portion where the electrostatic adsorption force is easily generated. Can be placed over a wide area on one side of the grip. Therefore, it is possible to suitably generate an electrostatic attraction force for adsorbing the article.

  In the above apparatus, it is preferable that the auxiliary electrode is formed on a surface of the both sides of the dielectric layer that is inwardly bent in the grip when the grip is bent in the first operating state.

  According to the above configuration, since the auxiliary electrode for generating the electrostatic adsorption force can be arranged on the surface in contact with the article when the article is gripped by the grip, the electrostatic adsorption force is efficiently applied to the article. Can work well.

  In the above device, it is preferable that the switching unit applies a predetermined potential difference between the pair of electrodes over a predetermined time when external power is input to the power supply unit.

  In the above grip, when the same potential difference is applied between the pair of electrodes over a long period of time, the grip is bent and deformed at a relatively slow speed. For a while after that, it was found that the effect of re-applying the potential difference causes the grip bending deformation to proceed rapidly (so-called memory effect).

  According to the above configuration, such a memory effect can be generated in advance. Therefore, when an article is actually gripped by a grip, the grip can be quickly bent using the memory effect.

In the above device, the grip preferably includes a protective layer made of an insulating material and covering at least the outer surfaces of the pair of electrodes.
According to the above configuration, contact between one electrode and the other electrode and contact between the electrode and the article can be suppressed, so that the degree of freedom in using the grip can be increased.

  In the above apparatus, the grip is preferably hung with the upper end portion supported, and has a shape that becomes narrower as the upper portion is directed upward.

  Here, if the grip is a rectangular sheet and is hung with the entire upper end supported, the upper part of the grip is difficult to bend, and the entire grip is difficult to bend. On the other hand, if the grip is a rectangular sheet and is hung in a state where the center in the width direction of the upper end is supported, the upper part of the grip is easily bent. However, in this case, before the potential difference applied to the grip is increased, both sides in the width direction (so-called shoulder portions) of the upper portion of the grip are deformed so as to hang down due to their own weight. May have a structure in which it is difficult to grasp the article.

  According to the above configuration, since the upper part of the grip becomes narrower toward the upper side, when the grip is hung with the upper end supported, the upper side of the grip It is possible to suppress deformation of the portion so that both sides in the width direction hang down. As a result, when the potential difference applied between the pair of electrodes is small (for example, when no potential difference is applied), it is easy to keep the grip unbent. Can be made easier.

  In the above apparatus, the polyrotaxane includes polyethylene glycol as a linear molecule, a cyclodextrin as a plurality of cyclic molecules slidably inserted into the linear molecule, and an end of the linear molecule. And an adamantaneamine as a blocking group that suppresses elimination of the cyclic molecule from the linear molecule can be employed.

In the above apparatus, the dielectric layer is preferably one in which a crosslinking agent having an isocyanate group at the terminal is used.
According to the above configuration, the bending deformation amount of the grip when the potential difference between the pair of electrodes is increased can be increased.

  According to the article gripping apparatus of the present invention, an actuator including a polyrotaxane can be effectively used.

The side view which shows schematic structure of the article | item holding | grip apparatus of one Embodiment. The exploded perspective view of a grip. Sectional drawing of the center part of a grip. Sectional drawing which shows schematic structure of the center part of a grip. Sectional drawing which shows schematic structure of the lower part of a grip. (A) is a photograph showing a situation before voltage application to the grip, (b) is a photograph showing a situation where voltage application to the grip is being performed, and (c) is a voltage application to the grip. A photograph showing the situation where the support bar has been moved up with the grip. (A) And (b) is a principle figure for demonstrating the principle in which a grip bends. The time chart which shows the result of having applied the positive DC voltage to the test grip and measuring the deformation amount of the grip. The time chart which shows the result of having measured the deformation | transformation amount of the grip, performing in the aspect which stops the application of DC voltage to the grip for a test temporarily. The time chart which shows the result of having applied the negative DC voltage to the grip for a test, and measuring the deformation amount of the grip. The time chart which shows the result of having applied the negative DC voltage after applying a positive DC voltage to the test grip, and measuring the deformation amount of the grip.

Hereinafter, an embodiment of the article gripping device will be described.
As shown in FIG. 1, the apparatus main body 11 has a support bar 12 protruding from the side wall thereof. The support bar 12 is provided in such a manner that it can move relative to the apparatus main body 11 in the vertical and horizontal directions.

  The support bar 12 is attached with a sheet-like grip 20 for gripping an article in a state of being hung by the support bar 12. The grip 20 is supported by the support bar 12 via the wiring 13 at its upper end (specifically, a plus terminal 21 and a minus terminal 22 attached to the end). Note that the upper end of the grip 20 may be directly connected to the support bar 12.

  The apparatus main body 11 has a power supply device 14 as a power supply unit. A plus terminal 21 of the grip 20 is connected to the plus terminal 15 of the power supply device 14 via the wiring 13. The minus terminal 22 of the grip 20 is connected to the ground terminal 16 of the apparatus main body 11 through the wiring 13. Thereby, a DC voltage can be applied to the grip 20 from the power supply device 14.

  The apparatus main body 11 has an electronic control unit 17 composed of, for example, a microcomputer. The electronic control device 17 is one of a “first operation state” in which voltage is applied to the grip 20 and a “second operation state” in which voltage application to the grip 20 is stopped. It functions as a switching unit that selectively switches to. Note that the switching of the operating state of the power supply device 14 by the electronic control device 17 is performed according to the operation of the manual switch by the operator, or automatically performed in a predetermined pattern stored in the electronic control device 17 in advance. And so on.

Hereinafter, the specific structure of the grip 20 will be described in detail.
As shown in FIGS. 2 and 3, the grip 20 is formed on both surfaces of a dielectric layer 31 which is a sheet-like cured film containing a crosslinked polyrotaxane and the dielectric layer 31 so as to sandwich the dielectric layer 31 therebetween. It has a multilayer structure comprising a pair of electrodes (positive electrode 32 and negative electrode 33) and a pair of protective layers 34 and 35 covering both surfaces of the grip 20. In the grip 20 (specifically, the dielectric layer 31 and the protective layers 34 and 35), the upper part (upper part 23) has a rectangular shape with the same width, and the central part (central part 24) is the upper part 23. The lower end portion (lower portion 25) has a rectangular shape with the same width starting from the lower end of the central portion 24. The grip 20 has a structure in which a positive electrode 32 is sandwiched between one surface of the dielectric layer 31 and the protective layer 34, and a negative electrode 33 is sandwiched between the other surface of the dielectric layer 31 and the protective layer 35. It has become.

  The dielectric layer 31 is formed as follows. That is, a sheet-like cured film containing a crosslinked polyrotaxane (thickness = 0.05 mm in this embodiment) is formed by heating and curing a composition containing polyrotaxane under reduced pressure conditions. A film is used as the dielectric layer 31.

  The composition containing the polyrotaxane used for forming the dielectric layer 31 used in this embodiment is the same as Example 2 of Patent Document 1, and includes polyethylene glycol as a linear molecule and cyclodextrin as a cyclic molecule. And adamantaneamine as a blocking group. Further, the composition used for forming the dielectric layer 31 includes the substances described in [Substance A] to [Substance G] below. [Substance A] Polyrotaxane. [Material B] Block copolymer containing polysiloxane (polycaprolactone-polydimethylsiloxane-polycaprolactone block copolymer having an isocyanate group at the terminal). [Material C] Block polymer containing no polysiloxane (polypropylene glycol having an isocyanate group at the end). [Material D] Polypropylene glycol diol. [Material E] Catalyst for deprotection (dibutyltin dilaurate). [Material F] Silicone additive (“DBL-C31” manufactured by GELEST). [Material G] Antioxidant (“IRGANOX1726” manufactured by BASF). In the present embodiment, the above [Substance C] corresponds to a crosslinking agent.

The pair of electrodes (positive electrode 32 and negative electrode 33) is formed by applying carbon black powder (Ketjen Black [EC-300J]) to the dielectric layer 31.
The basic shapes of the positive electrode 32 and the negative electrode 33 are the same in a plan view (see arrow A in FIG. 2). Specifically, portions of the positive electrode 32 and the negative electrode 33 that are disposed in the central portion 24 of the grip 20 have a trapezoidal shape that becomes narrower as it goes upward. Further, the portions of the positive electrode 32 and the negative electrode 33 that are disposed in the lower portion 25 of the grip 20 are so-called comb teeth (a plurality of [in the present embodiment, seven in this embodiment] extending portions 32a extending linearly downward. 33a has a shape arranged in parallel at equal intervals in the width direction. A portion of the positive electrode 32 disposed on the upper portion 23 of the grip 20 extends in a band shape upward and is connected to the plus terminal 21. On the other hand, a portion of the negative electrode 33 disposed on the upper portion 23 of the grip 20 extends in a band shape upward and is connected to the negative terminal 22.

  FIG. 4 schematically shows a cross-sectional structure of the central portion 24 of the grip 20. As shown in FIG. 4, the positive electrode 32 of the grip 20 is connected to the plus terminal 15 of the power supply device 14 via the plus terminal 21 (see FIG. 1) and the wiring 13. Further, the negative electrode 33 of the grip 20 is connected to the ground terminal 16 of the apparatus body 11 via the negative terminal 22 (see FIG. 1) and the wiring 13.

  As shown in FIGS. 1 and 2, in addition to the positive electrode 32, an auxiliary electrode 36 is provided between one surface of the dielectric layer 31 in the grip 20 and the protective layer 34. The auxiliary electrode 36 is formed by applying carbon black powder (Ketjen Black [EC-300J]) to the dielectric layer 31 in the same manner as the pair of electrodes (positive electrode 32 and negative electrode 33).

  The auxiliary electrode 36 is disposed at a position spaced from the positive electrode 32. Specifically, the portions of the auxiliary electrode 36 disposed at the upper portion 23 and the central portion 24 of the grip 20 extend in a band shape along the outer edge of the grip 20 between the end portion of the grip 20 and the positive electrode 32. ing. A portion of the auxiliary electrode 36 disposed in the lower portion 25 of the grip 20 includes a base portion 36b extending in a strip shape along the lower outer edge of the grip 20, and a plurality of (this book) extending linearly upward from the base portion 36b. In the embodiment, it has a shape having seven extended portions 36a, and the extended portions 36a are arranged in parallel at equal intervals in the width direction of the grip 20 (so-called comb-like shape). Yes.

  Each extending portion 36a of the auxiliary electrode 36 is arranged so as to alternate with the extending portion 32a of the positive electrode 32 in the width direction. The upper end of the auxiliary electrode 36 is connected to the ground terminal 16 of the apparatus main body 11 via the minus terminal 22 and the wiring 13 (FIG. 1).

  FIG. 5 schematically shows a cross-sectional structure of the lower portion of the grip 20. As shown in FIG. 5, between one surface of the dielectric layer 31 of the grip 20 and the protective layer 34, an extended portion 32 a of a positive electrode 32 connected to the positive terminal 15 of the power supply device 14, and the device The extension portions 36a of the auxiliary electrodes 36 connected to the ground terminal 16 of the main body 11 (see FIG. 1) are arranged so as to be in alternate positions in the width direction.

  The pair of protective layers 34 and 35 are formed of a stretchable insulating material (specifically, a crosslinked polyrotaxane). Therefore, the grip 20 has a structure in which the outer surfaces of the positive electrode 32 and the auxiliary electrode 36 are covered with the protective layer 34, and the outer surface of the negative electrode 33 is covered with the protective layer 35. By providing the protective layers 34 and 35 on the grip 20, the positive electrode 32 and the negative electrode 33 (or the auxiliary electrode 36) come into contact with each other, and each electrode (the positive electrode 32, the negative electrode 33, and the auxiliary electrode 36). Therefore, it is possible to increase the degree of freedom in using the grip 20.

  In addition, the method of forming the grip 20 having the dielectric layer 31 (sheet-like cured film containing a crosslinked polyrotaxane) and the dielectric layer 31 described above is a cured film disclosed in Patent Document 1 (in detail, the This is the same as Example 2) and the method for forming the dielectric sheet with electrode layer having the cured film, and detailed description thereof is omitted here.

  From the results of various experiments and simulations by the inventors, the grip 20 is greatly bent by applying a DC voltage (for example, 1200 volts) between the positive electrode 32 and the negative electrode 33, while the voltage It has been discovered that by stopping the application, it can be restored to the state before bending.

  In the article gripping apparatus according to the present embodiment, using such characteristics, the grip 20 is bent by applying a voltage to bend the article, or the voltage application is stopped and the grip 20 is restored to the state before the grip 20 is bent. By doing so, the article once grasped is released.

Hereinafter, the operation | movement aspect of the article | item holding | grip apparatus of this embodiment is demonstrated, referring FIG.
FIG. 6 is a photograph showing a result of an experiment conducted by the inventors to lift the article J using the grip 20. Specifically, FIG. 6A is a photograph showing a situation before voltage application to the grip 20, and FIG. 6B is a photograph showing a situation where voltage application to the grip 20 is being performed. (C) is a photograph showing a situation in which voltage is applied to the grip 20 and the support bar 12 is moved upward together with the grip 20.

Here, first, an operation mode of the article gripping apparatus when no voltage is applied to the grip 20 (specifically, between the positive electrode 32 and the negative electrode 33) will be described.
As shown in FIG. 6A, when no voltage is applied to the grip 20, the grip 20 is not bent and deformed. Therefore, at this time, the grip 20 is simply hung from the support bar 12 and is not wound around the article J.

  Here, if the grip is a rectangular sheet and is hung on the support bar 12 in a state where the entire upper end is supported, the upper part of the grip is difficult to bend, so the entire grip is also difficult to bend. . On the other hand, if the grip is a rectangular sheet and is hung from the support bar 12 while supporting the center in the width direction of the upper end, the upper portion of the grip is easily bent. However, in this case, before applying a voltage to the grip, both side portions in the width direction (so-called shoulder portions) of the upper portion of the grip are deformed so as to hang down due to their own weight, and the grip is difficult to grip the article. There is a risk of structure.

  In this regard, in this embodiment, the upper portion (the upper portion 23 and the central portion 24) of the grip 20 has a shape that becomes narrower as it goes upward. Therefore, although the grip 20 is suspended from the support bar 12 with the upper end of the grip 20 supported, both sides in the width direction of the upper portion of the grip 20 (so-called shoulder portions) ) Is hardly present, so that both side portions can be prevented from being deformed so as to hang down. Thereby, when the voltage is not applied to the grip 20, it becomes easy to maintain the state where the grip 20 is not bent, so that it is possible to easily hold the article by bending the grip 20.

Next, an operation mode of the article gripping apparatus when a voltage is applied to the grip 20 will be described.
As shown in FIG. 6B, when a voltage is applied to the grip 20, the grip 20 is bent. As a result, the grip 20 is wound around the article J, and the article J is held by the grip 20.

The principle that the grip 20 is bent by applying a voltage is considered as follows.
As shown in FIGS. 7A and 7B, when a DC voltage is applied between the positive electrode 32 and the negative electrode 33 of the grip 20, the electrostatic stress and the electrode plate that are generated inside the grip 20. Due to the thinning force, the dielectric layer 31 is compressed in the thickness direction and expanded in the in-plane direction. In addition, since a strong electric field is applied at this time, a space charge distribution is generated inside the dielectric layer 31 and the charge distribution inside the dielectric layer 31 becomes non-uniform, so that the stress distribution inside the dielectric layer 31 is also non-uniform. Become. Specifically, in the portion on the negative electrode 33 side in the dielectric layer 31, the degree of compression increases due to an increase in charge compared to the portion on the positive electrode 32 side in the dielectric layer 31. Due to this stress distribution, the amount of expansion in the in-plane direction (indicated by a white arrow in FIG. 7A) in the portion of the dielectric layer 31 on the negative electrode 33 side becomes the positive electrode 32 side of the dielectric layer 31. This is larger than the amount of extension in the in-plane direction at the portion (indicated by a solid arrow in FIG. 7A). As a result, as shown in FIG. 7B, the grip 20 including the dielectric layer 31 is bent so that the positive electrode 32 side of the dielectric layer 31 is on the inner side in the bending direction.

  Since the grip 20 bends according to such a principle, in order to bend the grip 20 appropriately, it is desirable that the dielectric layer 31 has a high dielectric constant and high flexibility. Polyrotaxane has a higher dielectric constant and higher flexibility than common elastomers (such as silicon rubber and acrylic rubber). In view of this point, a crosslinked body of polyrotaxane is employed as the dielectric layer 31 in this embodiment.

  In addition, it has been confirmed by the inventors that the dielectric layer 31 of the present embodiment has a bias in the space charge distribution inside. On the other hand, although the component factor causing space charge distribution is unknown, it is presumed that a crosslinking agent having an isocyanate group at the terminal is involved.

Here, the speed of bending deformation of the grip 20 when a voltage is applied will be considered.
FIG. 8 shows the result of measuring the amount of deformation of the grip by applying a DC voltage (800 volts) to the test grip. In this measurement, a small sample (grip for test) that bends up and down when a voltage is applied is prepared and the grip is placed with its upper end fixed. The amount of movement in the horizontal direction of the lower end of the grip from the pre-deformation position at the time of voltage application was detected as the “deformation amount”.

  As shown in FIG. 8, when a voltage is applied to the grip (time t11), the grip bends in a direction in which the portion on the positive electrode 32 side is inward of the bending direction (direction in which the amount of deformation increases in FIG. 8). become. The speed of bending deformation of the grip at this time is extremely fast in the initial stage of deformation (time t11), and then gradually decreases (time t11 to t12), and eventually becomes a substantially constant speed (time t12 to t13). And so on. When the voltage application to the grip is stopped (time t13), the grip is quickly restored to the state before deformation (deformation amount≈0). As is apparent from the measurement results, it cannot be said that the bending speed of the grip can be sufficiently increased when a voltage is simply applied to the grip.

FIG. 9 shows the result of measuring the “deformation amount” while the application of the DC voltage to the test grip is temporarily stopped.
As shown in FIG. 9, when the voltage application is temporarily stopped after applying the voltage to the grip for a predetermined time (time t21 to t22) (time t22), the grip has a shape before the voltage application (deformation amount≈0). ) To restore promptly. Further, when the voltage application to the grip is resumed immediately after that (time t23), the grip quickly deforms (returns) to the shape (deformation amount≈ “K”) when the voltage application is stopped immediately before. Become. Thereafter, the deformation speed of the grip becomes substantially constant (after time t23).

  As is apparent from this measurement result, in the grip 20, the bending deformation proceeds at a relatively slow speed when the voltage is applied in a state where the voltage is not applied for a long period of time, whereas the voltage is applied. For a while after being bent to some extent by the above, a phenomenon (so-called memory effect) in which the bending deformation rapidly proceeds by applying a voltage again occurs. It has been confirmed from the results of various experiments by the inventors that the memory effect of the grip 20 is maintained for at least several hours.

  Therefore, when using the article gripping apparatus of this embodiment, that is, when external power is input to the apparatus to start the apparatus, prior to applying a voltage to the grip 20 for gripping the article. It is desirable to apply a predetermined voltage to the grip 20 (between the positive electrode 32 and the negative electrode 33) for a predetermined time. Thus, the memory effect can be generated in advance in the grip 20, so that when the article is actually gripped by the grip 20, the grip 20 can be bent quickly using the memory effect. In this case, a voltage application time and an applied voltage at which the grip 20 can be bent at a reasonably fast speed are obtained in advance from the results of various experiments and simulations, and the voltage application time is set to the predetermined time. And the same applied voltage may be used as the predetermined voltage.

  As shown in FIGS. 2 and 5, between the dielectric layer 31 and the protective layer 34 in the grip 20, a part of the positive electrode 32 and a part of the auxiliary electrode 36 both formed in a comb-teeth shape, The teeth in the comb shape (the extended portion 32a of the positive electrode 32 and the extended portion 36a of the auxiliary electrode 36) are arranged so as to be alternately arranged. For this reason, when an article comes into contact with the outer surface of the grip 20 on the side where the positive electrode 32 and the auxiliary electrode 36 are formed in a state where a voltage is applied to the grip 20, the electrostatic force that attracts the article to the grip 20 is obtained. An adsorption force is generated between the outer surface of the grip 20 and the article. In addition, since the extended portion 32a of the positive electrode 32 and the extended portion 36a of the auxiliary electrode 36 are arranged alternately, the positive electrode 32 and the auxiliary electrode 36 having different potentials are arranged at intervals. The portion where the electrostatic attraction force is likely to be generated can be disposed over a wide range of the outer surface of the grip 20. Therefore, it is possible to suitably generate an electrostatic attraction force for adsorbing the article.

  Further, the positive electrode 32 and the auxiliary electrode 36 are formed on the both surfaces of the dielectric layer 31 on the inner surface in the bending direction of the grip 20 when the grip 20 is bent by voltage application. As a result, since the auxiliary electrode 36 for generating the electrostatic adsorption force can be disposed on the surface that comes into contact with the article when the article is gripped by the grip 20, the electrostatic adsorption force can be efficiently applied to the article. Can act.

  As described above, according to the present embodiment, as the force for gripping the article, in addition to the gripping force by the grip 20 to be bent, the electrostatic adsorption force acting between the grip 20 and the article can be used. The article can be gripped suitably.

  Then, as shown in FIG. 6C, by applying a voltage to the grip 20 and holding the article J by the grip 20, the support bar 12 is moved upward, so that the grip 20 is returned to the article J. Can be lifted up.

  After that, after the article J is placed on the table by moving the support bar 12 downward, when the voltage application to the grip 20 is stopped, the grip 20 is restored to the shape before the voltage application. As a result, the grip 20 is released from the article J as shown in FIG.

As described above, according to the present embodiment, the following effects can be obtained.
(1) The operating state of the power supply device 14 is a first operating state in which a voltage is applied to the grip 20 to bend the article by bending the grip 20, and the application of the voltage to the grip 20 is stopped. It was made to selectively switch to one of the 2nd operation states to which goods were released by restoring 20 in the state before bending. Therefore, the actuator (grip 20) containing polyrotaxane can be effectively used in an apparatus for gripping an article.

  (2) The auxiliary electrode 36 having the same potential as that of the negative electrode 33 is formed at a position spaced from the positive electrode 32 on one of both surfaces of the dielectric layer 31. Thereby, in addition to the gripping force by the grip 20 to be bent, the electrostatic attraction force acting between the grip 20 and the article can be used as the force for gripping the article. Will be able to.

  (3) A part of the positive electrode 32 and a part of the auxiliary electrode 36, both of which are formed in a comb shape between the dielectric layer 31 and the protective layer 34, are connected to each tooth (positive electrode 32) in the comb shape. The extended portions 32a of the auxiliary electrodes 36 and the extended portions 36a of the auxiliary electrode 36) are arranged alternately. As a result, a portion where the positive electrode 32 and the auxiliary electrode 36 having different potentials are spaced apart from each other, that is, a portion where the electrostatic attraction force is likely to be generated is disposed over a wide range on one outer surface of the grip 20. Therefore, the electrostatic attraction force for adsorbing the article can be suitably generated.

  (4) The positive electrode 32 and the auxiliary electrode 36 are formed on both surfaces of the dielectric layer 31 on the inner surface in the bending direction of the grip 20 when the grip 20 is bent by voltage application. As a result, since the auxiliary electrode 36 for generating the electrostatic adsorption force can be disposed on the surface that comes into contact with the article when the article is gripped by the grip 20, the electrostatic adsorption force can be efficiently applied to the article. Can act.

  (5) Prior to applying a voltage to the grip 20 for gripping the article, the grip 20 actually applies the article by applying a predetermined voltage to the grip 20 for a predetermined period of time. When gripping, the grip 20 can be bent quickly using the memory effect.

  (6) It has a pair of protective layers 34 and 35 made of an insulating material and covering both surfaces of the grip 20. As a result, contact between the positive electrode 32 and the negative electrode 33 (or the auxiliary electrode 36) and contact between each electrode (the positive electrode 32, the negative electrode 33, and the auxiliary electrode 36) and the article can be suppressed. The degree of freedom for using the grip 20 can be increased.

  (7) A shape in which the grip 20 is suspended from the support bar 12 with the upper end supported, and the upper portion (the upper portion 23 and the central portion 24) of the grip 20 becomes narrower toward the upper side. I made it. Thereby, when the voltage is not applied to the grip 20, it becomes easy to maintain the state where the grip 20 is not bent, so that it is possible to easily hold the article by bending the grip 20.

  (8) A crosslinked polyrotaxane using polypropylene glycol having an isocyanate group at the terminal as a crosslinking agent was employed as the dielectric layer 31. Therefore, the amount of bending deformation of the grip 20 at the time of voltage application can be increased.

<Modification>
The above embodiment may be modified as follows.
The positive electrode 32 and the positive terminal 21 of the grip 20 may be connected to the positive terminal 15 of the power supply device 14, and the negative electrode 33 and the negative terminal 22 may be connected to the negative terminal of the power supply device 14. In short, it is only necessary to provide a potential difference between the positive electrode 32 and the negative electrode 33.

  The second operating state of the power supply device 14 is the state before the grip 20 is bent with a very small potential difference (potential difference> 0) applied to the grip 20 (specifically, between the positive electrode 32 and the negative electrode 33). It may be in an operating state in which the grip 20 releases the article by restoring. In this case, the first operating state of the power supply device 14 may be set to an operating state in which the grip 20 is gripped by bending the grip 20 by increasing the potential difference applied to the grip 20.

  The positive electrode 32, the negative electrode 33, and the auxiliary electrode 36 are not limited to being formed by applying carbon black powder to the dielectric layer 31, but are elastomers (silicon rubber) containing conductive particles (carbon particles, platinum particles, etc.). Or acrylic rubber, natural rubber, etc.).

  The polyrotaxane used for forming the dielectric layer 31 (specifically, its linear molecules, cyclic molecules, and blocking groups) can be arbitrarily changed as long as the grip 20 employing the dielectric layer 31 bends appropriately upon application of voltage. It is. Examples of such polyrotaxane linear molecules, cyclic molecules, and blocking groups include those exemplified in Patent Document 1.

  A cured film (same as “Comparative Example 1” in Patent Document 1) formed on the basis of a composition not containing the substance B (block polymer containing polysiloxane) is used as the dielectric layer 31 of the grip 20. It may be used as It was confirmed that a space charge distribution similar to that in the above embodiment was produced in this cured film.

  The shape of the grip 20 can be arbitrarily changed as long as the grip 20 can be appropriately bent and extended through switching between the first operating state and the second operating state of the power supply device 14.

-The arrangement | positioning aspect of the grip 20 can be changed arbitrarily, such as not only arrange | positioning in the state suspended, but arrange | positioning on the stand.
Since the positive electrode 32 and the negative electrode 33 (or the auxiliary electrode 36) are in contact with each other (unnecessary contact between each electrode (the positive electrode 32, the negative electrode 33, and the auxiliary electrode 36) and the article is suppressed. If present, the protective layers 34 and 35 can be omitted.

  The arrangement mode of the pair of electrodes (positive electrode 32 and negative electrode 33) and the arrangement mode of the auxiliary electrode 36 in the grip 20 can be arbitrarily changed. For example, the pair of electrodes and the auxiliary electrode 36 may be arranged in a predetermined pattern. In addition, it is also possible to arrange the positive electrode 32 and the auxiliary electrode 36 so that the gap between them extends in a labyrinth. By increasing the arrangement range of the pair of electrodes, the grip 20 can be appropriately bent and deformed over a wide range. On the other hand, by increasing the arrangement range of the auxiliary electrode 36, it is possible to generate an electrostatic adsorption force for adsorbing an article over a wide range. In view of this situation, the pair of electrodes and the auxiliary electrode 36 may be arranged so that the force for bending and deforming the grip 20 and the force for adsorbing the article are generated in a mode suitable for gripping the article by the grip 20. .

The auxiliary electrode 36 may be omitted.
A positive DC voltage may be applied to the positive electrode 32 and the negative electrode 33 of the grip 20 from the power supply device 14, and a negative DC voltage may be applied.

  FIG. 10 shows a result of measuring the “deformation amount” by applying a negative DC voltage (−800 volts) to the test grip. As shown in FIG. 10, when a negative DC voltage is applied to the grip (time t31), the grip is thereafter in the direction in which the negative electrode 33 side portion is inward of the bending direction (the negative deformation amount in FIG. 10 is Bend in the direction of increasing). Therefore, according to the said structure, the grip 20 can be bent in the direction opposite to the bending direction in the said embodiment, and an article can be grasped now.

  FIG. 11 shows a result of measuring the “deformation amount” by applying a negative DC voltage (−800 volts) after applying a positive DC voltage (800 volts) to the test grip. As shown in FIG. 11, when a positive DC voltage is applied to the grip for a predetermined time (time t41 to t42) and the grip is bent and deformed in the positive direction, the voltage application is temporarily stopped (time t42). The grip is quickly restored to the shape before the voltage application (deformation amount≈ “0”). Immediately thereafter, when a negative DC voltage is applied to the grip (time t43), the grip once bends in the positive direction and then gradually recovers to the shape before voltage application (time t43 to t44). Thereafter, the vehicle gradually turns in the negative direction (time t44 to t45).

  As is apparent from this measurement result, when the grip 20 is bent and deformed once by applying a positive DC voltage, the grip 20 has a memory effect when the voltage application is stopped and a negative DC voltage is applied. It was found that after bending in the positive direction, the bending direction changed to the negative direction. Therefore, when the article gripping device is used by switching the bending direction of the grip 20, the grip 20 is applied to the grip 20 for a predetermined time before applying the voltage to the grip 20 for gripping the article. It is desirable to apply a predetermined voltage (voltage corresponding to the bending direction after switching [positive DC voltage or negative DC voltage]). As a result, a memory effect acting in the direction of bending deformation can be generated in advance in the grip 20 so that the grip 20 can be bent quickly when the grip 20 actually grips an article. Become.

  The voltage application for causing the memory effect in the grip 20 does not necessarily have to be executed.

  DESCRIPTION OF SYMBOLS 11 ... Apparatus main body, 12 ... Support bar, 13 ... Wiring, 14 ... Power supply device, 15 ... Positive terminal, 16 ... Grounding terminal, 17 ... Electronic control unit, 20 ... Grip, 21 ... Positive terminal, 22 ... Negative terminal, 23 ... upper part, 24 ... central part, 25 ... lower part, 31 ... dielectric layer, 32 ... positive electrode, 32a, 33a ... extension part, 33 ... negative electrode, 34, 35 ... protective layer, 36 ... auxiliary electrode, 36a ... extension Installation part, 36b ... Base part.

Claims (10)

A grip having a sheet-like dielectric layer containing a crosslinked polyrotaxane, and a pair of bending-deformable electrodes formed on both surfaces of the dielectric layer so as to sandwich the dielectric layer, and
A power supply unit connected to at least one of the pair of electrodes and applying a potential difference between the pair of electrodes; and
An operating state of the power supply unit is a first operating state in which the grip grips an article by bending the grip by increasing a potential difference applied between the pair of electrodes, and between the pair of electrodes. An article gripping device having a switching unit that selectively switches to one of a second operating state in which the grip is released by restoring the potential difference applied to the grip and restoring the grip to the state before bending. The article gripping apparatus according to claim 1, wherein one of the pair of electrodes is connected to a positive electrode of the power supply unit and the other electrode is grounded. The pair of electrodes includes one electrode connected to the power supply unit and the other electrode,
The grip is formed by forming an auxiliary electrode which can be bent and deformed at the same potential as the other electrode at a position spaced from the one electrode on one of both surfaces of the dielectric layer. 3. The article gripping apparatus according to 2. The one of the two surfaces of the dielectric layer, the one electrode and the auxiliary electrode are both arranged in a comb shape, and the teeth in the comb shape are arranged so as to be alternately arranged. Article gripping device. 5. The article grip according to claim 3, wherein the auxiliary electrode is formed on a surface of the both sides of the dielectric layer that is inwardly bent in the grip when the grip is bent in the first operation state. apparatus. 6. The switch according to claim 1, wherein when the external power is input to the power supply unit, the switching unit gives a predetermined potential difference between the pair of electrodes over a predetermined time. The article gripping apparatus according to claim 1. The article gripping device according to any one of claims 1 to 6, wherein the grip includes a protective layer made of an insulating material and covering at least the outer surfaces of the pair of electrodes. 8. The grip according to any one of claims 1 to 7, wherein the grip is hung in a state where the upper end is supported, and has a shape that becomes narrower as the upper portion is directed upward. The article gripping device according to Item. The polyrotaxane is disposed at the end of the linear molecule, polyethylene glycol as a linear molecule, a cyclodextrin as a plurality of cyclic molecules slidably inserted into the linear molecule, and the linear molecule. The article gripping device according to any one of claims 1 to 8, further comprising adamantaneamine as a blocking group that suppresses elimination of the cyclic molecule from the linear molecule. The article gripping device according to any one of claims 1 to 9, wherein the dielectric layer uses a crosslinking agent having an isocyanate group at a terminal.