Tokin Corporation

Nec Tokin Corporation

Sharp Kabushiki Kaisha Corporation

Katsunori Kumasaka

Yoshiaki Fuda

Hiroyuki Sato

Hiroshi Shima

Masafumi Katsuno

Yoshiyuki Abe

Noriaki Ikezawa

Masao Yamaguchi

Koichi Okamoto

Tetsuo Yoshida

Naoki Wako

Yoshihiro Ino

Osamu Yamazaki

Hutoshi Shiotani

Koichi Saito

Kouichi Shuta

Takeshi Mizuno

In the present invention, a device is provided with a main surface member, a piezoelectric body plate, a first support part, and a housing. The main surface member is used as a vibration plate. The piezoelectric body plate vibrates according to an electric signal. The first support part supports the piezoelectric body plate. The housing has a second support part that supports the main surface member and extends in a prescribed direction that intersects the main surface member. The first support part is secured to the second support so that the second support part vibrates in the prescribed direction according to the vibration of the piezoelectric body plate. The vibration of the piezoelectric body plate is transmitted to the main surface member via the first support part and the second support part, and due to this the main surface member vibrates to generate a sound.

Device generating sound

A piezoelectric vibration module includes a piezoelectric element, a wiring member connected to the piezoelectric element and drawn out to the outside, and an elastic plate bonded to one surface of the piezoelectric element, wherein the elastic plate is made of a silicone rubber.

Piezoelectric element, piezoelectric vibration module, and methods of manufacturing the same

A piezoelectric transformer () comprises a layered structure () formed by alternately stacking a plurality of internal electrodes () and a plurality of piezo-electric ceramics layers () in thickness direction, first electrodes () formed on side surfaces of said layered structure () and connected to said internal electrodes (), at least one pair of second electrodes () formed on the side surfaces in areas different from those of the first electrodes () and having a same potential, and a circuit board for driving the piezoelectric transformer. The piezoelectric transformer () is mounted on the circuit board. Each of the at least one pair of the second electrodes () opposite to each other is electrically connected to the circuit board.

Piezoelectric transformer

In a structure in which a piezoelectric transformer element ( ) is mounted on a circuit board ( ) equipped with a circuit component for driving the piezoelectric transformer element ( ), at least one of a fixing member ( ) and a supporting member ( ) made of an elastic material having flexibility is interposed between the piezoelectric transformer element ( ) and the circuit board ( ) so as to cover vibration node portions ( ) of the piezoelectric transformer element ( ) and at least a part of the remaining portion except the vibration node portions ( ). Thus, the piezoelectric transformer element ( ) is fixed to the circuit board ( ).

Mounting structure of piezoelectric transformer and method of mounting piezoelectric transformer

To provide a cold-cathode tube lighting circuit which quickly and smoothly carries out lighting of a cold-cathode tube and prevents damage of a piezoelectric transformer as an inverter transform in the lighting circuit, the lighting circuit is provided with a protection circuit for detecting a primary current of the piezoelectric transformer. The protection circuit stops operation of an oscillator for driving the piezoelectric transformer when the primary current is excessive. The protection circuit may be provided to detect excess of a secondary voltage of the piezoelectric transformer. When the cold-cathode tube is used as a backlight for a liquid crystal display driven by the use of a scanning frequency, a dimmer circuit is used for producing a dimmer signal with a dimmer frequency and a controlled duty ratio given by a manual selector for controlling start and stop of the oscillator according to a desired brightness of the backlight. The dimmer frequency is obtained from frequency division of the scanning frequency. The controlled duty ratio is also modified corresponding to the divided frequency.

Cold-cathode tube lighting circuit with protection circuit for

A power supply including a piezoelectric transformer mounted and electrically connected to a defined board region of a printed circuit board having circuit components for forming the power supply together with the piezoelectric transformer. The transformer has FPC for connecting the transformer and the printed circuit board and is bound together with the board region by a wrapping sheet. In an embodiment, the board region is defined by a slit through which the wrapping sheet is wrapped. In another embodiment, the FPC has lugs standing up thereon to connect with the electrodes of the transformer. In another embodiment, a hard plate supports and covers the FPC and the transformer on the printed circuit board. In the other embodiment, the FPC is formed into a cover case and covers and holds the transformer element when is fixed to the printed circuit board.

Piezoelectric transformer and power supply including the same

A piezoelectric transformer element is wrapped together with primary lead members and secondary lead members by a thin soft insulating sheet, with the primary and secondary lead members being exposed outside the wrapping sheet, so that the transformer element is small in size, and easy in handling, and mounting operation on a circuit board. The primary and secondary lead members can be formed of a flexible flat cable. In an electric power supply device using the piezoelectric transformer element, the transformer element, and the flexible flat cable are wrapped by the wrapping sheet together with a portion of a circuit board on which the transformer element and other circuit elements are mounted.

Piezoelectric transformer wrapped by wrapping member of soft insulating

A piezoelectric transformer comprising a rectangular plate of a piezoelectric material which is polarized in a thickness direction in a first half section of the plate in a longitudinal direction but is polarized in a width direction in a second half section of the remaining half section. A pair of primary electrodes are coated on the upper and the lower surfaces of the first half section and a pair of secondary electrodes are coated on the opposite side surfaces of the second half section, in an alternative structure, the plate is polarized in the thickness direction in opposite end sections of the plate having a size one third of length of the plate and polarized in width direction at the remaining middle section of plate between opposite end sections. The pair of primary electrodes formed on upper and lower surfaces of opposite end sections of plate and pair of secondary electrodes formed on opposite side surfaces of middle section. The pair of secondary electrodes may be deposited on upper or lower surfaces adjacent opposite side edges. In a voltage converter using the piezoelectric transformer, a pulse generator generates two voltage pulse signals having frequency equal to resonance frequency of transformer but being reverse to each other in phase, which signals are applied to primary electrodes, respectively to produce high voltage AC output across secondary electrodes isolated from primary electrodes.

Growing community of inventors

Sendai, Japan

Katsunori Kumasaka