JP4815753B2 - Piezoelectric actuator wiring method and flexible substrate - Google Patents

Description

  The present invention relates to a wiring method and a wiring board, and is particularly suitable for application to a wiring method of a bimorph type piezoelectric actuator and a flexible substrate for conductive connection to the piezoelectric actuator.

  Conventionally, as shown in FIG. 9, this type of bimorph type piezoelectric actuator 1 is bonded by sandwiching an intermediate electrode 3 made of a conductive material between piezoelectric ceramics 2A and 2B made of two ceramic thin plates. The surface electrodes 4A, 4B made of a conductive material formed on the outer surface of each of the piezoelectric ceramics 2A, 2B and the intermediate electrode 3 are wired so as to be polarized in opposite directions.

  In this piezoelectric actuator 1, when a driving voltage is applied from an external power source (not shown), a current flows in both piezoelectric ceramics 2A and 2B in the same direction as the polarization direction, while the intermediate electrode 3 is polarized. Since the current flows in the direction opposite to the direction, the piezoelectric ceramics 2A and 2B extend or shorten along the longitudinal direction, so that the piezoelectric actuator 1 as a whole exhibits a distortion proportional to the applied voltage in the direction of arrow a or in the opposite direction. Has been made to occur.

Here, the conventional piezoelectric actuator 1 has a surface electrode made of copper foil attached to the outer surface of each of the piezoelectric ceramics 2A and 2B, as shown in FIG. The lead wires 5A and 5B are pulled out as jumpers from predetermined portions of 4A and 4B, and the lead wire 6 is pulled out from one end of the intermediate electrode 3, and a bundle of these lead wires 5A, 5B and 6 is combined into a single connector 7. It is customary to connect with each other. (For example, refer to Patent Document 1).
JP 2004-94389 A (FIG. 6, [0045] and [0046])

  By the way, in the piezoelectric actuator 1 shown in FIG. 10, in order to connect the lead wires 6A and 6B from predetermined portions of the surface electrodes 5A and 5B attached to the outer surfaces of the piezoelectric ceramics 2A and 2B, the surface electrodes Generally, the end portions of the lead wires 6A and 6B are soldered onto the portions 5A and 5B.

  However, such a soldering method has a problem that the production efficiency is very poor in view of mass productivity. Further, the lead wires 6A and 6B may be peeled off from the copper foil pattern which is the surface electrodes 5A and 5B attached to the external surfaces of the piezoelectric ceramics 2A and 2B.

  Furthermore, when constructing a vibration functional unit using a plurality of piezoelectric actuators, the bending direction of each piezoelectric ceramic is mostly determined with respect to the polarity of the applied voltage. Need to be arranged to be the same.

  The present invention has been made in consideration of the above points, and an object of the present invention is to propose a wiring method of a piezoelectric actuator and a flexible substrate that can remarkably improve product reliability and production efficiency.

In order to solve this problem, in the present invention, in the wiring method of the piezoelectric actuator for electrically connecting the flexible substrate to the piezoelectric actuator, one end portion of the piezoelectric actuator is sandwiched from both sides of the flexible substrate. A first step of providing a holding portion having terminal shapes corresponding to a plurality of driving electrodes formed on both surfaces of one end portion of the piezoelectric actuator, and a holding portion of the flexible substrate, At the same time as sandwiching one end portion of the piezoelectric actuator from both sides, each driving electrode is provided with a second step of conducting connection corresponding to each terminal electrode, and in the first step, as a sandwiching portion of the flexible substrate, The piezoelectric actuator has opposing surfaces opposite to both surfaces of the piezoelectric actuator, and the piezoelectric actuators are provided on the opposing surfaces. First and second substrate portions each having a terminal electrode corresponding to each drive electrode of the data are provided, and in the second step, the first fold line is set with reference to a predetermined fold line set in the holding portion. The first substrate portion is folded and bonded to the second substrate portion, and in the first step, a dummy terminal electrode having one side coincident with the folding line is formed in the sandwiching portion .

  As a result, in this piezoelectric actuator wiring method, the peel strength of the flexible substrate with respect to the piezoelectric actuator can be remarkably increased as compared with the conventional method of drawing a jumper wire.

In the present invention, one end portion of the piezoelectric actuator has a shape that can be sandwiched from both sides, and terminal electrodes are respectively formed corresponding to the plurality of drive electrodes formed on both surfaces of the one end portion of the piezoelectric actuator. A sandwiching portion is provided , and the sandwiching portion has opposing surfaces that respectively oppose both surfaces of the piezoelectric actuator, and first and second terminal electrodes corresponding to the respective drive electrodes of the piezoelectric actuator are formed on the opposing surfaces. The first substrate portion is used by being folded back to the second substrate portion with reference to a predetermined folding line set in the clamping portion at the time of joining, and the clamping portion has one side that coincides with the folding line. dummy terminal electrodes are in so that have been formed.

  As a result, in this flexible substrate, a remarkably high peel strength can be easily obtained as compared with a conventional method of drawing a jumper wire.

As described above, according to the piezoelectric actuator wiring method of the present invention , the peel strength of the flexible substrate with respect to the piezoelectric actuator can be remarkably increased, and thus the reliability and production efficiency of the product can be remarkably improved. A wiring method can be realized.

Further, according to the flexible substrate of the present invention , a remarkably high peel strength can be easily obtained, and thus a flexible substrate that can remarkably improve the reliability and production efficiency of the product can be realized.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

(1) Configuration of portable information terminal according to the present embodiment In FIG. 1, reference numeral 10 denotes a portable information terminal according to the present embodiment as a whole, and a plurality of piezoelectric actuators 13 </ b> A to 13 </ b> A interposed between the display unit 11 and the touch panel 12. The 13D is controlled to vibrate according to the contact state of the user touching the touch panel 12, and the user is fed back with a pseudo tactile sensation such as a click feeling or a stroke feeling.

  The portable information terminal 10 has a main body portion 14 having a substantially square plate shape as a whole, and a display portion 11 formed of an LCD (liquid Crystal Display) for displaying images, characters, and the like on the upper central portion on the surface side. A touch panel 12 is provided in an overlapping manner, and an operation unit 15 including a press-type button group to which various functions are assigned is provided in a central lower part.

  As shown in FIG. 2, a holding frame 17, which is a frame having a plurality of piezoelectric actuators 13 </ b> A to 13 </ b> D fixed and held on the surface, is attached to the main body 14 so as to expose the display unit 11. The touch panel 12 is laminated and pasted so as to cover the piezoelectric actuators 13A to 13D on the frame 17.

  The touch panel 12 is a thin polyester film obtained by depositing a transparent conductive film (ITO) in a strip shape with a predetermined thickness, and the two polyester films are electrically connected to each other in the strip direction of the conductive film. It is formed so as to be bonded in a non-contact manner so as to maintain a typical insulating property.

  A thin plate-like frame 12A made of a conductive material is formed on the peripheral side of the touch panel 12 as a conductive path between two conductive films of a polyester film, and the flexible body is drawn from one end of the frame 12A. A current source (not shown) is conductively connected through the substrate 12B. When this touch panel 12 receives an external contact, a current flows through the corresponding portion of the conductive film of both polyester films, so that the contact position can be recognized as a coordinate position using the screen of the display unit 11 as a two-dimensional coordinate system. it can.

  The holding frame 17 has two holding portions 17FA and 17FC, 17FB and 17FD formed on the surface of a rectangular frame 17F along the longitudinal direction of the holding frame 17 at predetermined intervals, and the holding portions 17FA to 17FD. The piezoelectric actuators 13A to 13D are respectively fixed and held via an adhesive (not shown).

  Specifically, as shown in FIGS. 3A and 3B, the holding frame 17 is fixedly held on the surface of the frame 17F with the plurality of piezoelectric actuators 13A to 13D exposed (FIG. 3). (A)) On the back surface of the frame body 17F, a pair of flexible substrates (hereinafter referred to as first and second flexible substrates) 18 having a predetermined shape along both short sides of the frame body 17F. , 19 are attached, and the piezoelectric actuators (13A and 13B, 13C and 13D) facing each other through the opening in the frame 17F are electrically connected to the first and second flexible boards 18 and 19, respectively. (FIG. 3B).

  Here, the piezoelectric actuators 13A to 13D are of a bimorph type, and are configured as shown in FIGS. That is, the piezoelectric actuators 13A to 13D have a configuration in which an intermediate electrode 21 made of a conductive material is sandwiched between piezoelectric ceramics 20A and 20B made of two thin ceramic materials and bonded with an epoxy adhesive or the like. The surface electrodes 22A and 22B made of a conductive material respectively formed on the outer surfaces of the piezoelectric ceramics 20A and 20B and the intermediate electrode (for example, SUS301) 21 where only one piezoelectric ceramic 20A is exposed are polarized in opposite directions. Wired to 4A shows a top view, FIG. 4B shows a side view, and FIG. 4C shows a bottom view.

  Specifically, in each of the piezoelectric ceramics 20A and 20B, coating agents (for example, USR-2G (Tamura Chemical Research)) 23A and 23B are applied so as to cover the surface electrodes 22A and 22B except for one end portion of the outer surface. Thus, the surface electrodes 22A and 22B are exposed only at the one end portion. In one end portion of the outer surface of both piezoelectric ceramics 20A and 20B, part of the surface electrodes 22A and 22B (hereinafter referred to as ceramic electrodes) 22AX and 22BX is formed only on one half, and the other half on the other side. Only one of the piezoelectric ceramics 20B is exposed with a part of the intermediate electrode 21 electrically insulated from the surface electrode 22B (hereinafter, a part of the intermediate electrode 21 is referred to as a shim electrode 21X). On the other hand, nothing is applied to the other piezoelectric ceramic 20A (hereinafter, this portion is referred to as an electrodeless portion 20AN).

  Further, as shown in FIG. 5 showing a cross section taken along the line AA ′ of FIG. 4B, each of the piezoelectric ceramics 20A and 20B in the piezoelectric actuators 13A to 13D includes five layers each having a thickness of, for example, 0.05 [mm]. The intermediate electrode 21 is composed of, for example, 0.1 [mm] with a multilayer structure. Piezoelectric ceramics generally have the property that the bending force generated in proportion to its thickness increases, but on the other hand, both have the property of reducing the magnitude of the electric field obtained at a constant voltage in proportion to its thickness. In consideration of the above characteristics, by forming a multilayer structure, the bending force and the magnitude of the electric field per unit voltage as a whole can be sufficiently ensured in practical use.

  FIG. 6 shows the first and second flexible boards 18 and 19 described above. The first and second flexible substrates 18 and 19 are configured by attaching a predetermined wiring pattern made of copper foil or the like to a polyimide film having a predetermined shape by etching, and the shape and the wiring pattern are mutually connected. It is designed in advance so as to have a symmetrical relationship.

  Specifically, the first and second flexible substrates 18 and 19 have a generally long line shape as a whole, and T-shaped sandwiching portions 18A and 19A and a cross shape for sandwiching the piezoelectric actuators 13A to 13D at one end and the center, respectively. The clamping portions 18B and 19B are molded, and the connection terminals 18C and 19C are formed at the other end.

  The T-shaped sandwiching portions 18A and 19A are formed as a part of the flexible substrates 18 and 19 and have a partial line-symmetric shape with the dotted line A as a reference for folding. 18AF and 19AF, which are movable substrate portions (hereinafter referred to as movable substrate portions) 18AM and 19AM are used by being folded in the directions of arrows R1 and R2 with dotted lines A1 and B1 as folding lines. ing.

  The T-shaped sandwiching portions 18A, 19A are respectively provided with ceramic electrodes 22AX, 22BX, shim electrodes formed on the front and back surfaces of the piezoelectric actuators 13A, 13C at one ends of the fixed substrate portions 18AF, 19AF and the movable substrate portions 18AM, 19AM. Terminal electrodes are respectively formed corresponding to 21X and the electrodeless portion 20AN.

  Among these, in the fixed substrate portions 18AF and 19AF, terminal electrodes corresponding to the ceramic electrodes 22BX (hereinafter referred to as ceramic terminal electrodes) 30T and terminal electrodes corresponding to the shim electrodes 21X (hereinafter referred to as shim terminal electrodes). Both 31T are conductively connected to the wiring pattern. On the other hand, in the movable substrate portions 18AM and 19AM, the ceramic terminal electrode 32T corresponding to the ceramic electrode 22AX is conductively connected to the wiring pattern, but the terminal electrode corresponding to the non-electrode portion 20AN is connected to the wiring pattern. Without being electrically insulated (hereinafter referred to as a dummy terminal electrode 33D).

  Further, the T-shaped sandwiching portions 18A and 19A are fixed when the movable substrate portions 18AM and 19AM are folded using the dotted lines A1 and A2 as the folding lines with the piezoelectric actuators 13A and 13C positioned on the fixed substrate portions 18AF and 19AF. The shape and land pattern of the substrate portions 18AF and 19AF and the movable substrate portions 18AM and 19AM in advance so as to overlap each other (ceramic terminal electrode 30T and dummy terminal electrode 33D, shim terminal electrode 31T and ceramic terminal electrode 32T) overlap each other. Is designed.

  Similarly to the T-shaped sandwiching portions 18A and 19A, the cross-shaped sandwiching portions 18B and 19B are molded as a part of the flexible substrates 18 and 19, and the dotted lines B1 and B2 parallel to the dotted lines A1 and A2 are used as the folding reference. The movable substrate portions 18BM and 19BM are folded and used in the directions of arrows R3 and R4 with dotted lines B1 and B2 as folding lines with respect to the fixed substrate portions 18BF and 19BF.

  The cross-shaped sandwiching portions 18B and 19B are respectively provided with ceramic electrodes 22AX and 22BX, shim electrodes formed on the front and back surfaces of the piezoelectric actuators 13B and 13D at one ends of the fixed substrate portions 18BF and 19BF and the movable substrate portions 18BM and 19BM. Terminal electrodes are respectively formed corresponding to 21X and the electrodeless portion 20AN.

  Among these, in the fixed substrate portions 18BF and 19BF, the ceramic terminal electrode 35T corresponding to the ceramic electrode 22BX and the shim terminal electrode 36T corresponding to the shim electrode 21X are both conductively connected to the wiring pattern. On the other hand, in the movable substrate portions 18BM and 19BM, the ceramic terminal electrode 37T corresponding to the ceramic electrode 22AX is conductively connected to the wiring pattern, but the dummy terminal electrode 38D corresponding to the non-electrode portion 20AN is connected to the wiring pattern. Without being electrically insulated.

  Further, in the cross-shaped sandwiching portions 18B and 19B, when the movable substrate portions 18BM and 19BM are folded using the dotted lines B1 and B2 as the folding lines with the piezoelectric actuators 13B and 13D positioned on the fixed substrate portions 18BF and 19BF, the fixed substrate The shape and land pattern are previously set so that the terminal electrodes of the portions 18BF and 19BF and the movable substrate portions 18BM and 19BM overlap (the ceramic terminal electrodes 35T and the dummy terminal electrodes 38D, and the shim terminal electrodes 36T and the ceramic terminal electrodes 37T). Designed.

  The dummy terminal electrodes 33D formed on the movable substrate portions 18AM, 18BM, 19AM, and 19BM in the T-shaped sandwiching portions 18A and 19A and the cross-shaped sandwiching portions 18B and 19B of the first and second flexible substrates 18 and 19, In 38D, substantially square land portions 33DL and 38DL are formed relatively large in the vicinity of the folding lines (dotted lines A1, A2, B1, and B2) of the movable substrate portions 18AM, 18BM, 19AM, and 19BM. As a result, if one side of the land portions 33DL and 38DL is made to coincide with the folding line (dotted lines A1, A2, B1 and B2), the movable substrate portions 18AM, 18BM, 19AM and 19BM are indicated by arrows R1, R2, R3 and R4. When folded back in a direction, it is folded back naturally with one side of the land portions 33DL and 38DL having high hardness as a reference, so that the movable substrate can be remarkably easily made compared with the case where no land portions 33DL and 38DL are formed. The portions 18AM, 18BM, 19AM, and 19BM can be folded back with reference to a desired portion.

  The first flexible substrate 18 includes two wirings L1A electrically connected to the ceramic terminal electrodes 30T and 32T in the T-shaped sandwiching portion 18A and wiring L2A electrically connected to the shim terminal electrode 31T. In addition, four wirings L1A including two wirings L3A electrically conductively connected to the ceramic terminal electrodes 35T and 37T in the cross-shaped sandwiching portion 18B and two wirings L4A electrically conductively connected to the shim terminal electrode 36T are combined. To L4A are bundled together at the other end connection terminal 18C.

  The second flexible substrate 19 includes two wires L1B, which are conductively connected to the ceramic terminal electrodes 30T, 32T in the T-shaped sandwiching portion 19A, and a wire L2B, which is conductively connected to the shim terminal electrode 31T. In addition, four wirings L1A including two wirings L3B electrically connected to the ceramic terminal electrodes 35T and 37T and two wirings L4B electrically connected to the shim terminal electrode 36T in the cross-shaped holding portion 19B are combined. -L4B are bundled together at the connection terminal 19C at the other end.

  The first and second flexible substrates 18 and 19 have four wirings L1A to L4A and L1B to L4B that form connection terminals 18C and 19C at the other ends, respectively, and a main body portion 14 (FIG. 1) of the portable information terminal 10. Are connected to the connectors 50 and 51 provided in the connector.

  In the present embodiment, wires L1A and L3A that are electrically connected to the ceramic terminal electrodes 30T, 32T, 35T, and 37T in the T-shaped sandwiching portion 18A and the cross-shaped sandwiching portion 18B in the wiring pattern of the first flexible substrate 18, Of the wiring pattern of the second flexible substrate 19, the wirings L 2 B and L 4 B conducting to the shim terminal electrodes 31 T and 36 T in the T-shaped sandwiching portion 19 A and the cross-shaped sandwiching portion 19 B are connected in the main body 14 via the connector 50. 1 is electrically connected to the connector end 52A.

  Further, among the wiring patterns of the first flexible substrate 18, the wirings L 2 A and L 4 A that are electrically connected to the shim terminal electrodes 31 T and 36 T in the T-shaped sandwiching portion 18 A and the cross-shaped sandwiching portion 18 B and the wiring pattern of the second flexible substrate 19. Of these, the wiring L1B and L3B conducting to the ceramic terminal electrodes 30T, 32T, 35T, and 37T in the T-shaped holding portion 19A and the cross-shaped holding portion 19B are connected to the second connector end 52B in the main body portion 14 via the connector 51. And continuity connection.

  In the main body 14, the input and output ends of a pulse generator (not shown) are connected to the first and second connector ends 52A and 52B, so that the first and second pulse output ends 52A, An AC pulse having a predetermined level (for example, 18 [V]) and a predetermined width (for example, 45 [ms]) can be applied between 52B.

  Specifically, the CPU (Central Processing Unit) in the main body 14 has an output timing at which the plus (+) or minus (−) differential waveform of the first and second pulse output terminals 52A and 52B is optimal. Thus, two types of pulse signals having the same pulse width without a time lag are given to a bridge driver (not shown) in the pulse generator. In this case, “optimal” refers to a state in which the user's finger touching the touch panel 12 (FIG. 1) can feel as if the user has pressed the button. The bridge driver is driven based on two types of pulse signals to apply an AC pulse of one cycle between the first and second pulse output terminals 52A and 52B.

  In this way, the first and second flexible substrates 18 and 19 are generated from a pulse generator (not shown) because the substrate shape is line symmetrical and the wiring pattern is formed in the opposite direction. AC pulses are applied so that they are in opposite phases. As a result, the piezoelectric actuators 13A and 13B on the first flexible board 18 side and the piezoelectric actuators 13C and 13D on the second flexible board 19 side can be always distorted in the same direction. Thus, in the portable information terminal 10, the entire touch panel 12 can always be vibrated integrally in the same bending direction.

(2) Step of connecting first and second flexible boards to each piezoelectric actuator When connecting the first and second flexible boards 18 and 19 to each of the piezoelectric actuators 13A to 13D actually applied, A wiring connection processing procedure RT1 as shown in FIG. 7 is executed from step SP0 to step SP4. In this wiring connection processing procedure RT1, the case where the first flexible substrate 18 is connected to each piezoelectric actuator 13A, 13B will be described.

  First, with respect to the first flexible substrate 18, the ceramic terminal electrodes 30T, 32T, 35T, and 37T, the shim terminal electrodes 31T and 36T, and the dummy terminal electrodes 33D and 38D of the T-shaped sandwiching portion 18A and the cross-shaped sandwiching portion 18B are respectively soldered. At the same time, an adhesive such as double-sided adhesive paper is attached to a portion of the joint surface at the time of folding in each movable substrate portion 18AM, 18BM (or each fixed substrate portion 18AF, 18BF) excluding the electrodes (step). SP1).

  Subsequently, in the T-shaped sandwiching portion 18A and the cross-shaped sandwiching portion 18B of the first flexible substrate 18, the piezoelectric actuators 13A and 13B are fixed to the fixed substrate portions 18AF and 18BF and the movable substrate portion 18AM using a jig (not shown). It is sandwiched between 18BMs in a conductive state (step SP2).

  That is, one end of each of the piezoelectric actuators 13A and 13B is connected to each of the fixed substrate portions 18AF and 18BF of the T-shaped sandwiching portion 18A and the cross-shaped sandwiching portion 18B in the first flexible substrate 18, and the ceramic electrode 22BX and the shim electrode 21X are ceramic terminals. After positioning and contacting the electrodes 30T and 35T and the shim terminal electrodes 31T and 36T, the movable substrate portions 18AM and 18BM are folded back in the directions of the arrows R1 and R3 with reference to the folding lines A1 and B1, respectively. , 13B electrodeless portion 20AN and ceramic electrode 22AX are positioned and brought into contact with dummy terminal electrodes 33D and 38D and ceramic terminal electrodes 32T and 37T, respectively.

  Next, the T-shaped sandwiching portion 18A and the cross-shaped sandwiching portion 18B of the first flexible substrate 18 are thermally welded with the piezoelectric actuators 13A and 13B sandwiched between the fixed substrate portions 18AF and 18BF and the movable substrate portions 18AM and 18BM, respectively. As a result of the processing, the electrodes of the piezoelectric actuators 13A and 13B can be joined in a conductive state in correspondence with the terminal electrodes of the first flexible substrate 18 (step SP3).

(3) Operation and effect according to the present embodiment In the above configuration, as a step before the plurality of piezoelectric actuators 13A to 13D are fixedly held on the holding frame 17 attached to the main body 14 of the portable information terminal 10, The piezoelectric actuators 13 </ b> A to 13 </ b> D are conductively connected to the first and second flexible substrates 18 and 19.

  First, in the first and second flexible substrates 18 and 19, the T-shaped sandwiching portions 18A and 19A and the cross-shaped sandwiching portions including the fixed substrate portions 18AF, 18BF, 19AF and 19BF and the movable substrate portions 18AM, 18BM, 19AM and 19BM, respectively. The portions 18B and 19B are formed, while the fixed substrate portions 18AF, 18BF, 19AF, 19BF and the movable substrate portions 18AM, 18BM, 19AM, 19BM are formed on the same surface, on both surfaces of one end portion of each of the piezoelectric actuators 13A to 13D. A terminal electrode is formed corresponding to each formed electrode.

  In the T-shaped sandwiching portions 18A and 19A and the cross-shaped sandwiching portions 18B and 19B of the first and second flexible substrates 18 and 19, the movable substrate portion 18AM and the fixed substrate portions 18AF, 18BF, 19AF, and 19BF, respectively. 18BM, 19AM, and 19BM are folded back so that the piezoelectric actuators 13A to 13D are joined so as to sandwich each other, so that a remarkably high peel strength can be easily achieved as compared with a conventional method of pulling out a jumper wire. As a result, it is possible to remarkably improve the reliability with respect to a change with time due to self vibration.

  Further, the first and second flexible substrates 18 and 19 are formed so that the substrate shapes thereof are in a line symmetrical relationship and are arranged so that the wiring patterns are opposite to each other. When all the 13Ds are arranged so that the front and back directions are the same, all the piezoelectric actuators 13A to 13D are always in the same direction only by applying an AC pulse of opposite phase to the first and second flexible substrates 18 and 19. As a result, the entire touch panel 12 in the portable information terminal 10 can always be vibrated integrally in the same bending direction. Further, the degree of freedom in designing the first and second flexible boards 18 and 19 can be increased, and not only wiring can be easily drawn, but also assembly equipment, work, and parts can be shared.

  According to the above configuration, in the holding frame 17 attached to the main body portion 14 of the portable information terminal 10, the T-shaped sandwiching portions 18A and 19A and the cross-shaped sandwiching portion 18B of the first and second flexible substrates 18 and 19 are used. 19B, one end portions of the corresponding piezoelectric actuators 13A to 13D are sandwiched from both sides so that the movable substrate portions 18AM, 18BM, 19AM, and 19BM are folded with respect to the fixed substrate portions 18AF, 18BF, 19AF, and 19BF. As a result, it is possible to easily obtain a remarkably high peel strength as compared with the conventional method of pulling out a jumper wire, thus significantly improving the reliability and production efficiency of the product. it can.

(4) Other Embodiments In the above-described embodiments, the piezoelectric actuator wiring method according to the present invention is applied to the holding frame 17 attached to the main body 14 of the portable information terminal 10 as shown in FIG. Although the present invention is not limited to this, the main point is that a piezoelectric commander is used for vibration control of the touch panel, etc. In addition to this, a remote commander, LCD monitor, electronic notebook, portable The present invention can be widely applied to various input / output devices such as telephones, fixed telephones with screens, cash dispensers, personal computers, and home appliances.

  Further, in the above-described embodiment, the first and second flexible substrates 18 and 19 have a shape in which one end portions of the piezoelectric actuators 13A to 13D can be sandwiched from both sides, and the piezoelectric actuators 13A to 13A. Ceramic terminal electrodes 30T and 32T, shim terminal electrodes 31T and dummy terminal electrodes corresponding to ceramic electrodes 22BX and 22AX, shim electrodes 21X and electrodeless portions 20AN (plural drive electrodes) formed on both surfaces of one end of 13D, respectively. The case where the T-shaped sandwiching portions 18A and 19A and the cross-shaped sandwiching portions 18B and 19B (the sandwiching portions) on which 33D (terminal electrodes) are formed has been described. However, the present invention is not limited thereto, and As long as one end portion of each piezoelectric actuator 13A to 13D can be sandwiched from both sides and joined, It can be widely applied to clamping unit having the structure.

  In the case of the present embodiment, the T-shaped sandwiching portions 18A and 19A and the cross-shaped sandwiching portions 18B and 19B (sandwich portions) of the first and second flexible substrates 18 and 19 are respectively disposed on both surfaces of the piezoelectric actuators 13A to 13D. Ceramic terminal electrodes 30T and 32T, shim terminal electrodes corresponding to the ceramic electrodes 22BX and 22AX, the shim electrode 21X, and the electrodeless portion 20AN (drive electrode) of the piezoelectric actuators 13A to 13D. As the first and second substrate portions on which 31T and dummy terminal electrodes 33D (terminal electrodes) are respectively formed, the movable substrate portions 18AM, 18BM, 19AM, 19BM and the fixed substrate portions 18AF, 18BF, 19AF, 19BF are applied, Set to T-shaped clamping parts 18A and 19A and cross-shaped clamping parts 18B and 19B (clamping parts) With reference to the predetermined folding lines A1, A2, B1, and B2, the movable substrate portions (first substrate portions) 18AM, 18BM, 19AM, and 19BM are fixed to the fixed substrate portions (second substrate portions) 18AF, 18BF, 19AF, While the piezoelectric actuators 13A to 13D can be joined so as to sandwich the piezoelectric actuators 13A to 13D, various other configurations can be applied to the first and second substrate portions. Also good.

  Further, in the above-described embodiment, the T-shaped sandwiching portions 18A and 19A and the cross-shaped sandwiching portions 18B and 19B (sandwich portions) of the first and second flexible substrates 18 and 19 are connected to one end portions of the piezoelectric actuators 13A to 13D. Are sandwiched from both sides, and at the same time, the ceramic electrodes 22BX and 22AX, the shim electrode 21X and the electrodeless portion 20AN (drive electrode) are respectively connected to the ceramic terminal electrodes 30T and 32T, the shim terminal electrode 31T and the dummy terminal electrode 33D (terminal electrode). However, the present invention is not limited to this, and each drive electrode and the corresponding terminal electrode can be joined in a conductive state. If possible, various other methods may be used.

  INDUSTRIAL APPLICABILITY The present invention can be widely applied to various input / output devices that use a piezoelectric actuator to control vibration of a touch panel, in addition to a portable information terminal, in a piezoelectric actuator wiring method and a flexible substrate.

It is a perspective view which shows the external appearance structure of the portable information terminal by this Embodiment. It is a rough-line disassembled perspective view which shows the structure of a touchscreen and a holding frame. It is a rough-line top view which shows the surface and back surface of a holding | maintenance frame shown in FIG. It is the top view, side view, and bottom view which show the external structure of a piezoelectric actuator. It is a fragmentary sectional view of the piezoelectric actuator of FIG. It is a rough-line top view and block diagram with which it uses for description of the wiring state of the 1st and 2nd flexible substrate. It is a flowchart with which it uses for description of a wiring connection process procedure. It is a top view with which it uses for description of the connection process of the 1st and 2nd flexible substrate with respect to each piezoelectric actuator. It is a basic diagram with which it uses for description of the concept of the conventional bimorph type piezoelectric actuator. It is a rough-line perspective view which shows the external appearance structure of the conventional bimorph type piezoelectric actuator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 13A-13D ... Piezoelectric actuator, 2A, 2B, 20A, 20B ... Piezoelectric ceramics, 3, 21 ... Intermediate electrode, 4A, 4B, 22A, 22B ... Surface electrode, 10 ... Portable information terminal, 11 ...... Display unit, 12 ... Touch panel, 14 ... Main body unit, 15 ... Operation unit, 17 ... Holding frame, 18 ... First flexible substrate, 19 ... Second flexible substrate, 22AX, 22BX ... ... Ceramic electrode, 21X ... Shim electrode, 20AN ... No electrode part, 18A, 19A ... T-shaped clamping part, 18AF, 18BF, 19AF, 19BF ... Fixed substrate part, 18AM, 18BM, 19AM, 19BM ... Movable substrate part, 18B, 19B ... Cross-shaped clamping part, 35T, 37T ... Ceramic terminal electrode, 36T ... Shim terminal electrode, 38D ... Dummy terminal Poles 50, 51 ...... connectors, 52A ...... first connector end, 52B ...... second connector end, L1A~L4A, L1B~L4B ...... wiring, RT1 ...... wiring connection procedure.

Claims (4)

In the wiring method of the piezoelectric actuator for electrically connecting the flexible substrate to the piezoelectric actuator,
A part of the flexible substrate has a shape in which one end portion of the piezoelectric actuator can be sandwiched from both sides, and terminal electrodes respectively correspond to a plurality of drive electrodes formed on both surfaces of the one end portion of the piezoelectric actuator. A first step of providing the formed clamping part;
A second step of sandwiching the one end portion of the piezoelectric actuator from both sides of the sandwiching portion of the flexible substrate and simultaneously connecting the driving electrodes to the terminal electrodes, respectively ,
In the first step,
As the sandwiching portion of the flexible substrate, a first surface having opposing surfaces respectively opposed to both surfaces of the piezoelectric actuator, and the terminal electrodes corresponding to the drive electrodes of the piezoelectric actuator are formed on the opposing surfaces, respectively. And providing a second substrate portion,
In the second step,
The first substrate portion is folded and joined to the second substrate portion with reference to a predetermined fold line set in the clamping portion,
Furthermore, in the first step,
A method of wiring a piezoelectric actuator, wherein a dummy terminal electrode having one side that coincides with the folding line is formed on the clamping portion . In the first step,
2. The method of wiring a piezoelectric actuator according to claim 1, wherein the dummy terminal electrode is formed so that one piece of a square land portion which is a part of the dummy terminal electrode coincides with the folding line . The piezoelectric actuator has a shape in which one end portion can be sandwiched from both sides, and includes a sandwiching portion in which terminal electrodes are respectively formed corresponding to a plurality of drive electrodes formed on both surfaces of the one end portion of the piezoelectric actuator ,
The clamping part is
The first and second substrate portions each having a facing surface respectively opposed to both surfaces of the piezoelectric actuator, wherein the terminal electrodes corresponding to the drive electrodes of the piezoelectric actuator are formed on the facing surfaces, respectively.
At the time of joining, the first substrate portion is folded back to the second substrate portion using a predetermined fold line set in the holding portion as a reference,
Furthermore, the flexible board | substrate with which the dummy terminal electrode which has one side which corresponds to the said folding line is formed in the said clamping part . The dummy terminal electrode is
The flexible substrate according to claim 3, wherein the flexible substrate has a rectangular land portion, and one piece of the land portion is formed to coincide with the folding line .

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