Method for manufacturing an electrorheological device

Abstract

To easily provide manufacture of small quantities of many kinds of electric rheology device without requiring an expensive insert metal mold etc.SOLUTION: An electric rheology device comprises: an electrode 9 to which a flat reverse surface 7b of an ER sheet 7 is fitted by cutting the ER sheet 7 in a predetermined shape, the ER sheet 7 having ER particles 5 dispersed in an electric insulator 3 and also exposed on a top surface 7a; and a conductive adhesive layer 10 which is located between a fitting surface 9a of the electrode 9 and the reverse surface 7b of the ER sheet 7, the fitted surface 9a of the electrode 9 being stuck on the reverse surface 7b of the ER sheet 7.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrorheological device capable of electrically adjusting frictional force or adhesive force, and a manufacturing method thereof. [Background technology]

[0002] Conventional electrorheological devices include, for example, those described in Patent Document 1 that are applied to torque transmission devices and the like.

[0003] Such an electrorheological device is configured as a part of a multi-plate clutch, and is provided with a friction sliding material formed of an electrorheological sheet on one side of the clutch plate. The electrorheological sheet is an electrical insulator having electrorheological particles dispersed therein.

[0004] Therefore, by applying a voltage through a conductive clutch plate which functions as an electrode, the coefficient of friction with respect to the mating clutch plate can be changed.

[0005] Due to the characteristics of the clutch, such electrorheological devices require surface precision on the electrode surface, and in order to realize this precision, conventionally, electrorheological sheets and electrodes such as clutch plates have been integrated by insert molding, etc. However, this manufacturing method requires expensive insert molds for each electrorheological device, which makes it difficult to meet the demand for small-lot, high-mix production in recent years. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2013-177907 A Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved is to provide a method for easily producing a wide variety of electrorheological devices in small quantities without requiring expensive insert molds or the like. [Means for solving the problem]

[0008] The present invention relates to electrorheological particles in electrical insulators. of dispersion Let The electrorheological particles are exposed on one side and the other side is flat. N Electro-Rheological Sheet of , The electrode or the electrode-attached member is formed into a predetermined shape according to the surface to which the electrode or the electrode-attached member is attached, The above Of a given shape The other side of the electrorheological sheet or the above Electrode or The above Electrode-attached parts a conductive adhesive layer is attached to the mounting surface of the electrorheological sheet of the predetermined shape; The electrode or The above The mounting surface of the electrode-attached member The above conductive adhesive layer The two pieces are then pasted together with , Electrorheological Device a method for manufacturing an electrorheology device, comprising: fixing the electrode or the member with electrode and pressing the electrorheology sheet against the electrode or the member with electrode to remove air between the electrorheology sheet and the electrode or the member with electrode; the electrorheology sheet of a predetermined shape is annular; the air removal is performed by an air removal tool which applies pressure while rotating along the circumferential direction of the annular shape; and the air removal tool has protrusions which guide air to an inner or outer circumference of the annular shape in response to the rotation. to provide.

[0009] The present invention also relates to a method for manufacturing an electrorheological device, comprising the steps of: dispersing electrorheological particles in an electrical insulator, forming an electrorheological sheet having one side on which the electrorheological particles are exposed and the other side which is flat into a predetermined shape corresponding to a mounting surface of an electrode or an electrode-attached member; attaching a conductive adhesive layer to the other side of the electrorheological sheet of the predetermined shape or to the mounting surface of the electrode or the electrode-attached member; and bonding together the other side of the electrorheological sheet of the predetermined shape and the mounting surface of the electrode or the electrode-attached member with the conductive adhesive layer interposed therebetween. a voltage higher than a voltage used by the electrorheological device is applied through the electrodes to destroy the electrorheological particles aggregated and dispersed in the electrorheological sheet, thereby correcting bias in electrical resistance and removing electrophoretic impurities. to provide. Effect of the Invention

[0010] The present invention does not require expensive insert molds or the like, and can easily provide for the production of a wide variety of electrorheological devices in small quantities. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an electrorheological device according to a first embodiment. [Diagram 2] FIG. 2 is a schematic perspective view of an electrorheological device. [Diagram 3] FIG. 3(A) is a schematic cross-sectional view showing a state in which the paste is spread on a base film, and FIG. 3(B) is a schematic cross-sectional view showing the formation of a semi-finished sheet. [Figure 4] FIG. 4 is a schematic cross-sectional view showing the electrorheological sheet according to the first embodiment. [Diagram 5] FIG. 5 is a schematic perspective view showing a process of removing air from an electrorheological device using an air removal jig. [Figure 6] 6(A) is a schematic perspective view showing an air removal jig used in the air removal step of FIG. 5 as viewed from above, and FIG. 6(B) is a schematic perspective view showing the bottom surface of the air removal jig used in the air removal step of FIG. 5. [Figure 7] FIG. 7 is a schematic perspective view showing an electrode bonding and air evacuation process for an electrorheology device using an air evacuation jig according to a modified example. [Figure 8] FIG. 8 is a graph showing the characteristics of the electrorheological sheet before and after correction of the electrical resistive bias. [Figure 9] FIG. 9 is a schematic cross-sectional view showing an electrorheological device according to Example 2. As shown in FIG. [Figure 10] FIG. 10 is a schematic perspective view showing an electrode-attached member used in the electrorheological device of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The objective of providing a wide variety of electrorheological devices in small quantities with ease, without the need for expensive insert molds, has been achieved by punching out an electrorheological sheet adjusted to a specified precision and attaching it to electrodes or components with electrodes using a conductive adhesive layer.

[0013] The electrorheological device 1 comprises an electrorheological sheet 7, an electrode 9 or an electrode-attached member 90, and a conductive adhesive layer 10.

[0014] The electrorheological sheet 7 has electrorheological particles 5 dispersed in an electrical insulator 3, the electrorheological particles 5 exposed on a front surface 7a, and a flat back surface 7b. The electrode 9 or electrode-attached member 90 has an attachment surface 9a or 90a to which the back surface 7b of the electrorheological sheet 7 is attached. The conductive adhesive layer 10 is a conductive adhesive or conductive double-sided adhesive tape, and is located between the attachment surface 9a or 90a of the electrode 9 or electrode-attached member 90 and the back surface 7b of the electrorheological sheet 7, and bonds the attachment surface 9a or 90a of the electrode 9 or electrode-attached member 90 to the back surface 7b of the electrorheological sheet 7.

[0015] The method for manufacturing the electrorheology device 1 involves forming the electrorheology sheet 7 into a predetermined shape corresponding to the attachment surface 9a or 90a of the electrode 9 or electrode-attached member 90. A conductive adhesive layer 10 is attached to the back surface 7b of the electrorheology sheet 7 of this predetermined shape, or to the attachment surface 9a or 90a of the electrode 9 or electrode-attached member 90. Then, the back surface 7b of the electrorheology sheet 7 of the predetermined shape and the attachment surface 9a or 90a of the electrode 9 or electrode-attached member 90 are bonded together with the conductive adhesive layer 10 interposed therebetween.

[0016] In one embodiment, the electrode 9 or electrode-attached member 90 may be fixed and the electrorheological sheet 7 may be pressed against the electrode 9 or electrode-attached member 90 to remove air between the electrorheological sheet 7 and the electrode 9 or electrode-attached member 90.

[0017] When the electrorheological sheet 7 of a predetermined shape is annular, the air may be removed by an air removal tool 23 that applies pressure while rotating along the circumferential direction of the annular shape. In this case, the air removal tool 23 preferably has a protrusion 23aa that guides the air to the inner or outer circumference of the annular shape in response to the rotation.

[0018] The electrorheological device 1 may be configured such that a metal plate is placed on the surface of the electrorheological sheet and a voltage higher than the working voltage is applied between the electrodes 9 to remove electrophoretic impurities in the electrorheological sheet 7 and destroy low-resistance areas, thereby correcting the bias in electrical resistance. It is preferable that the metal plate be disposable and have a higher ionization tendency than the electrorheological particles.

[0019] In the electrorheology device 1, low molecular weight components may be removed from within the electrorheology sheet 7 by reducing pressure, heating, humidifying (adding water) or the like.

[0020] Furthermore, in the electrorheological device 1, the roughness and flatness of the surface of the electrorheological sheet 7 may be adjusted by polishing or the like. EXAMPLES

[0021] [Electro-rheological sheet] Fig. 1 is a schematic cross-sectional view showing an electrorheological device according to Example 1. Fig. 2 is a schematic perspective view of the electrorheological device.

[0022] The electrorheology device (hereinafter referred to as "ER device") 1 in Figs. 1 and 2 can be used in various equipment as a member capable of adjusting frictional force and adhesive force. In this embodiment, the ER device 1 is formed into a circular ring shape as a whole. However, the shape of the ER device 1 can be appropriately set depending on the application, etc.

[0023] The ER device 1 includes an electrorheological sheet (hereinafter referred to as “ER sheet”) 7, an electrode 9, and a conductive adhesive layer 10.

[0024] The ER sheet 7 is a sheet-like member in which electrorheological particles (ER particles) 5 are dispersed in an electrical insulator 3. The ER sheet 7 is capable of electrically adjusting frictional force and adhesive force by the electrorheological effect (hereinafter referred to as the "ER effect"). The ER sheet 7 of this embodiment is formed into a circular sheet shape in accordance with the ER device 1.

[0025] The frictional force and the adsorption force are adjusted on a front surface 7a, which is one side surface of the ER sheet 7. An electrode 9 is provided on a back surface 7b, which is the other side surface of the ER sheet 7.

[0026] The rubber hardness of the ER sheet 7 is preferably in the range of 30 to 100 IRHD (JIS K 6253), and the thickness is preferably 0.1 mm to 3 mm.

[0027] The electrical insulator 3 used in the ER sheet 7 may be any material having electrical insulation properties, and may be formed of elastomers, for example, silicone resins, urethane resins, fluorine resins, synthetic rubbers such as NBR, etc. In this embodiment, the electrical insulator 3 is made of elastic silicone resin. The electrical insulator 3 is formed to a certain thickness, for example, about 0.1 mm to 3.0 mm. The specific gravity of the electrical insulator 3 is about 0.9 to 2.2. From the viewpoint of expression of the ER effect, the volume resistivity of the electrical insulator 3 is set to 1×10 10 It is preferable that the resistivity is Ω·cm or more.

[0028] The ER particles 5 are conductive fillers that exhibit the ER effect when dispersed in the electrical insulator 3. Examples of the ER particles 5 that can be used include solid particles such as metal particles, metal oxide particles, and silica gel, carbon particles, and composite particles consisting of a core material of an organic polymer compound and a surface layer of electrically semiconducting inorganic particles.

[0029] The particle size of the ER particles 5 is about 0.1 μm to 100 μm. The specific gravity of the ER particles 5 is, for example, about 0.8 to 11.0, and is about 1.16 in this embodiment. The volume resistivity of the ER particles 5 is 1×10 3 ~1×10 8 The range of Ω·cm is preferable. The dispersion ratio of the ER particles 5 in the electrical insulator 3 is preferably 5 vol % to 90 vol %, and more preferably 40 vol % to 90 vol %.

[0030] In order to achieve a sufficient ER effect, the volume resistivity of the ER sheet 7 must be 1×10 7 ~1×1011 If the volume resistivity of the resulting ER sheet 7 is within this range, in addition to the ER particles 5, a conductive filler or a non-conductive filler may be appropriately added to adjust the friction coefficient between the surface of the ER sheet 7 and the clutch plate.

[0031] Examples of the conductive filler include metal particles, metal oxide particles, solid particles such as silica gel, carbon particles, etc., and examples of the non-conductive filler include silica powder, glass powder, alumina powder, talc powder, boron nitride powder, organic polymer compound particles, etc. The particle size of the conductive filler or non-conductive filler to be added is preferably about 0.1 μm to 100 μm.

[0032] A plurality of ER particles 5 are randomly exposed on the front surface 7a, which is one side surface of the ER sheet 7. Exposed here means that the ER particles 5 protrude from the surface of the electrical insulator 3 of the ER sheet 7. The other side surface, the back surface 7b, of the ER sheet 7 is flat and the ER particles 5 are not exposed. A state in which the ER particles 5 are not exposed refers to a state in which the ER particles 5 do not protrude from the electrical insulator 3, and also includes a state in which the ER particles 5 are visible from the outside.

[0033] Therefore, the front surface 7a of the ER sheet 7 has a friction coefficient that depends on the exposed ER particles 5, and the back surface 7b of the ER sheet 7, where the ER particles 5 are not exposed, has a friction coefficient that depends on the electrical insulator 3. In this embodiment, the ER particles 5 have a lower friction coefficient than the electrical insulator 3, so the front surface 7a of the ER sheet 7 has a lower friction coefficient than the back surface 7b. The back surface 7b of the ER sheet 7 is provided with the electrode 9 as described above.

[0034] The electrode 9 is made of a circular metal plate corresponding to the ER device 1. The electrode 9 has an ER sheet 7 attached to an attachment surface 9a via a conductive adhesive layer 10. In this embodiment, the attachment surface 9a is treated with a primer to improve adhesion.

[0035] The conductive adhesive layer 10 is located between the attachment surface 9a of the electrode 9 and the back surface 7b of the ER sheet 7, and bonds the attachment surface 9a of the electrode 9 to the back surface 7b of the ER sheet 7. The conductive adhesive layer 10 can be in the form of a conductive adhesive applied in liquid or gel form, or it can be in the form of a conductive double-sided adhesive tape or the like.

[0036] When using the ER device 1, a voltage is applied via the electrodes 9 arranged on the rear surface 7b of the ER sheet 7. This makes it possible to adjust the adsorptive force, frictional force, etc., of the front surface 7a of the ER sheet 7 with respect to an object.

[0037] In this embodiment, the ER particles 5 exposed on the surface of the ER sheet 7 sink into the electrical insulator 3 in response to application of a voltage, increasing the adsorptive force and frictional force that depend on the electrical insulator 3. The ER sheet 7 may generate an attractive force by electrical force based on Maxwell stress. In this case, the ER particles 5 do not need to be immersed, and the electrical insulator 3 may be configured to have no elasticity.

[0038] To reduce the adhesive force or frictional force with respect to the object, the application of voltage can be stopped.

[0039] [Method of manufacturing electrorheological devices] The manufacturing method of the electrorheological device of the embodiment of the present invention includes 1. a kneading process, 2. a dividing and rolling process, 3. a hardening process, 4. a cutting process, 5. an impurity removal process, 6. an electrode bonding process, 7. an air removal process, and 8. a process of correcting electrical resistance bias and removing impurities.

[0040] First, an ER sheet 7 is formed through 1. kneading process, 2. extrusion rolling process, 3. hardening process, 4. cutting process, and 5. impurity removal process. Then, the ER sheet 7 is attached to an electrode 9 through 6. electrode bonding process, 7. air removal process, and 8. correction of electrical resistance bias and impurity removal process, to obtain an ER device 1.

[0041] 1. Mixing process The binder 12 and the ER particles 5 are kneaded with a kneader or the like, and the ER particles 5 are dispersed in the binder 12 to form a kneaded paste 13 (see FIG. 3(A)). At this time, a conductive filler or a non-conductive filler may be added as appropriate. When kneading, it is preferable to pre-disperse the ER particles 5 and other fillers in a closed system. In addition, it is preferable to knead using a material that is almost solvent-free.

[0042] The binder 12 has a degree of fluidity that allows the ER particles 5 to be appropriately dispersed, and is changed into the electrical insulator 3 by a subsequent curing process. In this embodiment, for example, liquid-type RTV silicone rubber (manufactured by Shin-Etsu Chemical Co., Ltd.) is used as the binder 12. In this embodiment, composite particles are used as the ER particles 5.

[0043] The dispersion ratio of the ER particles 5 in the binder is 40 vol% to 90 vol%. By dispersing the ER particles 5 in the binder 12 at such a dispersion ratio, the Young's modulus of the paste 9 is about 100 to 2500 kPa. Note that the Young's modulus of the paste 13 only needs to be such that the layer shape can be maintained at least on a flat surface.

[0044] 2. Separation and rolling process FIG. 3(A) is a schematic cross-sectional view showing a state in which paste 13 is spread on a base film 15, and FIG. 3(B) is a schematic cross-sectional view showing the formation of a semi-finished sheet 19.

[0045] As shown in Fig. 3(A), in the spreading and rolling process, the paste 13 is spread on a base film 15, which is a base material. When spreading, the paste 13, which has been formed into a plate or sheet shape in advance, is placed on the base film 15. The plate thickness of the paste 13 at this time is set to be larger than the plate thickness of the ER sheet 7. The base film 15 can be, for example, a PET film.

[0046] 3(B), the base film 15 having the paste 13 thereon is passed between a pair of pressure rollers 17a and 17b to be rolled. The pressure rollers 17a and 17b preferably have mirror surfaces.

[0047] By this rolling, the surface 13a of the paste 13 is uniformly rolled against the base film 15. At this time, the surface 13a of the paste 13 is formed flat. The paste 13 may be flattened by sandwiching it between a pair of mirror bodies. In this case, one of the mirror bodies is peeled off from the paste 13, and the other mirror body is used as the base material, and the base film 15 can be omitted.

[0048] In this way, the paste 13 is spread in a layer on the base film 15, and the surface 13a is formed flat to obtain a semi-finished sheet 19. The thickness of the semi-finished sheet 19 is, for example, 0.1 mm to 3.0 mm at the portion of the paste 13. If the base film 15 is made of a transparent material, it becomes possible to visually check for the presence of foreign matter or air.

[0049] 3.Curing process The binder 12 in the semi-finished sheet 19 is cured to form the electrical insulator 3 shown in Fig. 1. The method of curing is appropriately set depending on the properties of the binder 12, and moisture curing, heat curing, UV curing, etc. can be used.

[0050] The curing process in this embodiment is moisture curing, and under conditions of, for example, a temperature of 40° C. and a humidity of 50%, curing can be achieved in about 16 hours.

[0051] Due to the curing treatment, front surface 13a of paste 13 is open and not covered by base film 15, and therefore shrinks to form the surface of electrical insulator 3. As a result, ER particles 5 are randomly exposed on front surface 7a of ER sheet 7 according to their dispersion state. In addition, back surface 13b of paste 13 is covered by base film 15 and does not shrink to the extent that ER particles 5 are exposed, and in this state forms electrical insulator 3 with base film 15 attached.

[0052] 4.Cutting process 4, the ER sheet 7 from which impurities have been removed after the curing process is punched out using a form or cut into a predetermined shape (annular in this embodiment) corresponding to the attachment surface 9a of the target electrode 9. In this way, the ER sheet 7 is held on the base film 15 until the cutting process, which makes it possible to prevent foreign matter from entering the back surface 7b.

[0053] 5.Impurity removal process The hardened semi-finished sheet 19 may be subjected to a process of removing low molecular weight components by a process of reducing pressure, humidifying (adding water), or the like.

[0054] 6. Electrode adhesion process 4, the base film 15 is peeled off from the electrical insulator 3, and the electrode 9 is adhered to the back surface 7b of the ER sheet 7 with a conductive adhesive layer 10. Specifically, the conductive adhesive layer 10 is attached to the back surface 7b of the ER sheet 7 having a predetermined shape or to the attachment surface 9a of the electrode 9. Then, the back surface 7b of the ER sheet 7 having a predetermined shape and the attachment surface 9a of the electrode 9 are attached to each other with the conductive adhesive layer 10 interposed therebetween.

[0055] 7. Air removal process After the electrode 9 is bonded to the ER sheet 7, the ER sheet 7 is pressed by an air removal tool 23 to remove the air trapped between the ER sheet 7 and the electrode 9.

[0056] Fig. 5 is a schematic perspective view showing the air removal process of the ER device 1 using the air removal jig 23. Fig. 6(A) is a schematic perspective view showing the air removal jig 23 used in the air removal process of Fig. 5 as viewed from above, and Fig. 6(B) is a schematic perspective view showing the bottom surface of the air removal jig 23 used in the air removal process of Fig. 5.

[0057] 5, in Example 1, a base jig 21 and an air vent jig 23 are used. The base jig 21 is provided with a support recess 21a and a support protrusion 21b that correspond to the annular shapes of the ER sheet 7 and the electrode 9. The air vent jig 23 presses the ER sheet 7 against the electrode 9 while rotating about an axis along the annular shape of the ER sheet 7. This air vent jig 23 is provided with a rotating portion 23a, a driving shaft portion 23b, and a load adjustment weight 23c.

[0058] As shown in FIG. 6, the air vent jig 23 has a ridge 23aa. The ridge 23aa is provided in a spiral shape on the rotating part 23a. In this embodiment, a plurality of ridges 23aa are provided at equal intervals in the rotation direction. The ridges 23aa guide air to the inner or outer circumference of the annular shape according to the rotation of the rotating part 23. The center of the rotating part 23a is provided with a fitting hole 23ab. The load adjustment weight 23c is formed, for example, in an annular shape, and is attached to the air vent jig 23 with the drive shaft part 23b inserted therethrough. The load adjustment weight 23c may be omitted.

[0059] When removing air, the ER sheet 7 with the electrode 9 adhered thereto is set in the support recess 21a of the base jig 21 shown in Fig. 5. The outer peripheral edges of the ER sheet 7 and the electrode 9 are fitted and supported in the support recess 21a, and their central holes are fitted into the support protrusion 21b. The ER sheet 7 and the electrode 9 are held concentrically by the support protrusion 21b. In this state, the electrode 9 is received and fixed from below in the support recess 21a, and the ER sheet 7 is exposed upward.

[0060] Next, the air vent jig 23 is lowered to insert the rotating part 23a into the supporting recess 21a, and the lower surface of the rotating part 23a is brought into contact with the ER sheet 7. The fitting hole 23ab of the rotating part 23a is fitted into the supporting protrusion 21b and set.

[0061] When a pressing force and a rotating force are applied to the drive shaft portion 23b, the rotating portion 23a presses the ER sheet 7a against the electrode 9. This pressing is performed by the rotating ridges 23aa in this embodiment. At this time, the ridges 23aa guide the air between the electrode 9 and the ER sheet 7 toward the inner or outer periphery in the radial direction, and the air that has reached the inner or outer periphery of the ER sheet 7 is discharged to the outside.

[0062] FIG. 7 is a schematic perspective view showing an electrode bonding and air evacuation process of the ER device 1 using an air evacuation jig 23 according to a modified example.

[0063] As shown in FIG. 7, the ER sheet 7 from which the base film 15 has been peeled off, the conductive double-sided adhesive tape 10 as a conductive adhesive layer, and the electrode 9 are supported in this order within the supporting recess 21a.

[0064] The adhesion and air removal between the ER sheet 7 and the electrode 9 are completed by operating the air removal jig 23 in the support recess 21a in the same manner as described above. In this example, the electrode adhesion step and the air removal step can be performed simultaneously.

[0065] 8. Correction of electrical resistance bias and removal of impurities After the electrodes 9 are attached to the ER sheet 7, a voltage higher than the operating voltage is applied to the ER sheet 7 to correct the bias in electrical resistance of the ER sheet 7.

[0066] FIG. 8 is a graph showing the characteristics before and after the correction of the bias in electrical resistance of the ER sheet 7 and the removal of impurities.

[0067] As shown in Figure 8, when the ER particles 5 in the ER sheet 7 are in a dispersed state with a bias in electrical resistance due to an aggregated state with low electrical resistance caused by insufficient dispersion, etc., current easily flows through the aggregated parts with low electrical resistance of the ER particles 5 when a voltage is applied. In addition, if the ER sheet 7 contains a trace amount of raw materials or ionic impurities generated during the manufacturing process as impurities, current easily flows when a voltage is applied. For this reason, the current increases sharply temporarily as shown by line segment B in Figure 8, and then becomes constant. In this case, the peak b where the current increases sharply makes it difficult to stably operate the ER sheet 7 and the ER device 1.

[0068] In contrast, in this embodiment, when the voltage used is, for example, 500V, a higher voltage, for example, 600V to 1500V, which is 1.2 to 3 times the voltage used, more preferably 750V to 1000V, which is 1.5 to 2 times the voltage used, is applied intermittently, for example, for 1 to 120 minutes, more preferably 30 to 90 minutes. As a result, the electrically low resistance aggregated parts of the ER particles 5 are destroyed by overcurrent or discharge and become electrically high resistance. Furthermore, impurities in the ER sheet 7 are also electrophoresed by the voltage application and are discharged to the counter electrode.

[0069] Therefore, the ER particles 5 aggregated and dispersed in the ER sheet 7 are destroyed to correct the bias in electrical resistance and also remove electrophoretic impurities, thereby reducing the height of peak a as shown by line segment A in Fig. 8, and allowing the ER sheet 7 and the ER device 1 to perform stable operation at the operating voltage from the beginning of use. Note that the reduction in the height of peak a is preferably 1% to 50% of the height of peak b before the reduction.

[0070] In the electrorheology device 1, low molecular weight components may be removed from within the electrorheology sheet 7 by reducing pressure, heating, humidifying (adding water) or the like.

[0071] Furthermore, the electrorheological device 1 may have the surface roughness and flatness of the electrorheological sheet 7 adjusted by polishing or the like. In this case, it is preferable to adjust the surface roughness Ra to about 2 μm to 40 μm. If Ra is less than 2 μm, strong ringing occurs between the ER sheet 7 and the opposing surface upon application of a voltage, and the dechucking property of the opposing surface deteriorates. If Ra is more than 40 μm, stable contact between the ER sheet 7 and the opposing surface cannot be obtained, and a sufficient ER effect cannot be obtained.

[0072] As described above, the ER device 1 of this embodiment comprises an ER sheet 7 in which ER particles 5 are dispersed in an electrical insulator 3, the ER particles 5 are exposed on a front surface 7a, and a flat back surface 7b; an electrode 9 whose mounting surface 9a is attached to the back surface 7b of the ER sheet 7; and a conductive adhesive layer 10 located between the mounting surface 9a of the electrode 9 and the back surface 7b of the ER sheet 7, and bonding the mounting surface 9a of the electrode 9 to the back surface 7b of the ER sheet 7.

[0073] Therefore, compared to a device in which the electrical insulator 3 and the electrode 9 are directly bonded together, it is possible to obtain an ER device 1 that maintains quality relatively inexpensively and easily in response to demands for small-lot, high-mix production without using expensive molds, etc.

[0074] The manufacturing method of the ER device 1 is to form the ER sheet 7 into a predetermined shape corresponding to the mounting surface 9a of the electrode 9, and to attach a conductive adhesive layer 10 to the back surface 7b of the ER sheet 7 having the predetermined shape or to the mounting surface 9a of the electrode 9. Then, the back surface 7b of the ER sheet 7 having the predetermined shape and the mounting surface 9a of the electrode 9 are bonded together with the conductive adhesive layer 10 interposed therebetween.

[0075] Therefore, the ER device 1 can be obtained easily and at a relatively low cost while maintaining the quality in response to demands for small-lot, high-mix production without using expensive molds or the like.

[0076] Furthermore, in the manufacturing method of this embodiment, the electrode 9 is fixed and the ER sheet 7 is pressed against the electrode 9 to remove air from between the ER sheet 7 and the electrode 9, so that an ER device 1 with better quality can be obtained.

[0077] In addition, when the ER sheet 7 of a predetermined shape is annular, air is removed by an air removal tool 23 that rotates and presses along the circumferential direction of the ring, and the air removal tool 23 can have a protrusion 23aa that guides air to the inner or outer circumference of the ring as it rotates.

[0078] In this case, air can be easily removed from the ER sheet 7 by simply rotating the air removal jig 23 while pressing the ER sheet 7. A weight can be inserted into the central axis 23b of the air removal jig 23 to adjust the pressing force according to the physical properties of the ER sheet 7 and conductive adhesive layer 10 used, making it possible to remove air with an optimal pressing force. The air removal jig 23 can be made of inexpensive general-purpose materials such as standard products or made using a 3D printer.

[0079] After the ER sheet 7 is attached to the electrode 9, a voltage higher than the operating voltage is applied to the ER sheet 7 via the electrode 9, so that the ER particles 5 aggregated and dispersed in the ER sheet 7 are destroyed, the electrical resistance bias is corrected, and electrophoretic impurities are also removed.

[0080] Therefore, in this embodiment, the ER particles 5 aggregated and dispersed in the ER sheet 7 are destroyed, the bias in electrical resistance is corrected, and electrophoretic impurities are also removed, thereby improving the quality of the ER device 1. EXAMPLES

[0081] Fig. 9 is a schematic cross-sectional view showing an electrorheological device according to Example 2, and Fig. 10 is a schematic perspective view showing an electrode-attached member used in the electrorheological device of Fig. 9. Note that the basic configuration of this example is common to Example 1, and components that are the same as or correspond to those of Example 1 are given the same reference numerals and redundant explanations will be omitted.

[0082] The ER device 1 of this embodiment is formed by attaching an ER sheet 1 to an electrode-attached member 90 with a conductive adhesive layer 10 and an insulating adhesive layer 11. The electrode-attached member 90 has electrodes 9A and 9B provided on a surface 27a of an insulating support 27.

[0083] The insulating support 27 may be made of any material having electrical insulation properties, such as elastomers, for example, silicone resins, urethane resins, fluorine resins, synthetic rubbers such as NBR, PET films, imide films, glass, glass epoxy boards, ceramic boards, phenol boards, etc. The insulating support 27 of this embodiment is formed in a rectangular sheet shape. The thickness of the insulating support 27 is, for example, 0.01 mm to 50 mm, and can be arbitrarily selected according to the required characteristics of the device, regardless of the thickness of the ER sheet 7.

[0084] The electrodes 9A and 9B are formed in a comb-like planar shape and have a plurality of teeth 9Aa and 9Ba. The teeth 9Aa and 9Ba of the electrodes 9A and 9B are alternately arranged at intervals. The teeth 9Aa and 9Ba of the electrodes 9A and 9B can be formed by various methods. For example, the teeth 9Aa and 9Ba can be formed by printing a conductive paste on the insulating support 27 and then curing it, inkjet coating of a conductive ink, pattern etching of the insulating support 27 with a conductor attached thereto, bonding of a patterned metal foil to the insulating support 27, forming a pattern on the insulating support 27 by sputtering or vapor deposition, etc.

[0085] The height, width, and electrode spacing of the teeth 9Aa and 9Ba of the electrodes 9A and 9B can be selected as desired to suit the required characteristics of the device. If the physical properties of the raw materials used are known, the optimal values ​​for the height, width, and electrode spacing may be calculated using an electric field calculation method.

[0086] The insulating adhesive layer 11 can improve the dielectric strength between the electrodes 9A and 9B and reduce the dielectric breakdown (discharge) between the electrodes 9A and 9B. The insulating adhesive layer 11 is made of an insulating adhesive or an insulating double-sided adhesive tape, and is arranged in a strip shape between the teeth 9Aa and 9Ba of the electrodes 9A and 9B. A conductive adhesive layer 10 of a conductive adhesive or a conductive double-sided adhesive tape is arranged on the surfaces of the electrodes 9A and 9B. The ER sheet 7 is attached to the surface 90a, which is the attachment surface of the electrode-attached member 90, via the insulating adhesive layer 11 and the conductive adhesive layer 10.

[0087] In the second embodiment, the same effects as those in the first embodiment can be achieved. [Explanation of symbols]

[0088] 1. Electrorheological Device 3 Electrical insulators 5. Electrorheological Particles 7. Electrorheological Sheet 7a Surface (one side) 7b Back side (other side) 9 electrodes 9a Mounting surface 10 Conductive adhesive layer 90 Electrode-attached parts 90a Mounting surface

Claims

1. Electrorheological particles are dispersed in an electrical insulator, and the electrorheological sheet is formed so that the electrorheological particles are exposed on one side and the other side is flat, and the electrorheological sheet is shaped in a predetermined shape corresponding to the surface to which the electrode or the electrode-equipped member is to be attached; A conductive adhesive layer is attached to the other side surface of the electrorheological sheet having a predetermined shape or to the mounting surface of the electrode or the electrode-attached member; the other side surface of the electrorheological sheet having a predetermined shape and the surface to be attached of the electrode or the electrode-attached member are bonded together with the conductive adhesive layer interposed therebetween; 1. A method for manufacturing an electrorheological device, comprising the steps of: the electrodes or the member with electrodes are fixed, and the electrorheology sheet is pressed against the electrodes or the member with electrodes to remove air between the electrorheology sheet and the electrodes or the member with electrodes; The shaped electrorheological sheet is annular, The air venting is performed by an air venting jig that rotates and presses along the circumferential direction of the annular shape, and the air venting jig has a protrusion that guides air to the inner circumference or outer circumference of the annular shape in response to the rotation. A method for manufacturing an electrorheological device.

2. Electrorheological particles are dispersed in an electrical insulator, and the electrorheological sheet is formed so that the electrorheological particles are exposed on one side and the other side is flat, and the electrorheological sheet is shaped in a predetermined shape corresponding to the surface to which the electrode or the electrode-equipped member is to be attached; A conductive adhesive layer is attached to the other side surface of the electrorheological sheet having a predetermined shape or to the mounting surface of the electrode or the electrode-attached member; the other side surface of the electrorheological sheet having a predetermined shape and the surface to be attached of the electrode or the electrode-attached member are bonded together with the conductive adhesive layer interposed therebetween; 1. A method for manufacturing an electrorheological device, comprising the steps of: applying a voltage higher than the operating voltage of the electrorheological device through the electrodes to destroy the electrorheological particles aggregated and dispersed in the electrorheological sheet, thereby correcting the bias in electrical resistance and removing electrophoretic impurities; A method for manufacturing an electrorheological device.

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