1. An insulating varnish that is applied onto a surface of a conductor, subsequently passes through a die to remove the excess applied insulating varnish, and is then dried or baked to form an insulating coating film on the surface of the conductor, the insulating varnish having a viscosity of 10 Pa\xb7s or more at 30\xb0 C.
2. The insulating varnish according to claim 1, containing no filler.
3. The insulating varnish according to claim 2, being a polyimide precursor solution.
4. An insulated electrical wire comprising an insulating coating film obtained by applying the insulating varnish according to claim 1 onto a conductor, and subsequently baking the insulating varnish.
5. The insulated electrical wire according to claim 4, wherein the conductor is a flat conductor having a rectangular cross section.
6. The insulated electrical wire according to claim 5, wherein, for 30 cross sections of the insulating coating film at intervals of 50 cm in the longitudinal direction of the electrical wire, with respect to an average of film thicknesses at 16 points on each of the cross sections (average film thickness of 16 points\xd730 sections=480 points), a variation ratio represented by a formula below is 20% or less:
Variation ratio (%)=(4\u03c3average film thickness)\xd7100
(where \u03c3 in the formula represents the standard deviation.)
7. An insulated electrical wire comprising an insulating coating film obtained by applying the insulating varnish according to claim 2 onto a conductor, and subsequently baking the insulating varnish.
8. An insulated electrical wire comprising an insulating coating film obtained by applying the insulating varnish according to claim 3 onto a conductor, and subsequently baking the insulating varnish.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An apparatus for generating vibrations, the apparatus comprising:
a housing having an internal space;
a direction changing member installed in the housing so as to be disposed in the internal space;
a piezoelectric actuator fixed to the direction changing member such that a horizontal deformation thereof is restrained, and deforming the direction changing member by a horizontal deformation thereof; and
a vibrator fixed to the direction changing member and vertically displaced in a vertical direction according to a vertical deformation of the piezoelectric actuator,
wherein the piezoelectric actuator comprises
positive electrode layers and negative electrode layers iteratively alternately vertically laminated,
piezoelectric element layers interposed between the positive electrode layers and the negative electrode layers, respectively,
a positive electrode connection pillar provided in a position corresponding to less than 50% of maximum displacement in the event of driving and penetrating the electrode layers and the piezoelectric element layers to connect the positive electrode layers, and
a negative electrode connection pillar provided in a position corresponding to less than 50% of maximum displacement in the event of driving and penetrating the electrode layers and the piezoelectric element layers to connect the negative electrode layers.
2. The apparatus of claim 1, wherein the direction changing member comprises:
a fixed end fixed to the housing;
horizontal portions extending from the fixed end to both sides in a horizontal direction;
vertical portions extending from horizontal outer portions of the horizontal portions downwardly in a vertical direction; and
displacement extending portions extending from vertical lower portions of the vertical portions to both sides in a horizontal direction and having the vibrator fixed to both sides thereof in the horizontal direction.
3. The apparatus of claim 2, wherein the piezoelectric actuator is provided in a space formed by the horizontal portions and the vertical portions.
4. The apparatus of claim 2, wherein the piezoelectric actuator is attached to one surface of at least any one of an upper surface in a vertical direction and end and side surfaces in a horizontal direction.
5. The apparatus of claim 1, wherein the housing comprises a bracket on which the direction changing member is installed, and a case covering the bracket and incorporated with the bracket to provide an internal space.
6. The apparatus of claim 1, further comprising a board attached to the bracket and providing power to the piezoelectric actuator.
7. The apparatus of claim 1, wherein the positive electrode layers have a quadrangular shape having a horizontal side and a vertical side, and the positive electrode connection pillar and the negative electrode connection pillar are provided in a position corresponding to less than 50% of maximum displacement in the event of driving in a horizontal direction.
8. The apparatus of claim 7, wherein the positive electrode layer has a positive dummy pattern formed on one side of a portion corresponding to less than 50% of maximum displacement in a vertical direction in the event of driving in a horizontal direction, and separated from the positive electrode layer,
the negative electrode layer has a negative dummy pattern formed in the other side of the portion corresponding to less than 50% of maximum displacement in a vertical direction in the event of driving in the horizontal direction, and separated from the negative electrode layer,
the positive electrode is connected in a penetrative manner vertically in the other side in a vertical direction where the negative dummy pattern is provided, and
the negative electrode connection pillar is connected in a penetrative manner vertically on one side in the vertical direction where the positive electrode dummy pattern is provided.
9. The apparatus of claim 8, wherein the positive electrode dummy pattern and the negative electrode dummy pattern are provided symmetrically, based on the center of the piezoelectric actuator in the vertical direction and have the same shape.
10. The apparatus of claim 7, wherein the vertical side is shorter than the horizontal side.
11. The apparatus of claim 8, wherein the lowermost layer of the electrode layers does not have a dummy pattern.
12. The apparatus of claim 11, wherein only a connection pillar having a corresponding polarity is connected to the lowermost layer of the electrode layers.