Abstract: A piezoelectric microblower includes a vibrating plate including a piezoelectric element and arranged to be driven in a bending mode by applying a voltage of a predetermined frequency to the piezoelectric element, and a blower body arranged to fix both ends or a periphery of the vibrating plate and to define a blower chamber between the blower body and the vibrating plate, an opening being provided in a portion of the blower body facing a central portion of the vibrating plate. In a portion of the blower chamber corresponding to the central portion of the vibrating plate, a partition is provided around the opening and a resonance space is defined inside of the partition. A size of the resonance space is set such that a driving frequency of the vibrating plate and a Helmholtz resonance frequency of the resonance space correspond to each other.

Abstract: In a piezoelectric-actuator driving circuit for driving a piezoelectric actuator, an amplifier circuit amplifies a signal output from a feedback circuit and supplies the amplified signal to a non-inverting amplifier circuit and an inverting amplifier circuit. The non-inverting amplifier circuit amplifies the output voltage of the amplifier circuit with a predetermined gain and applies the amplified voltage to a first terminal of the piezoelectric actuator. The inverting amplifier circuit inverts and amplifies the output voltage of the amplifier circuit with the same gain as that of the non-inverting amplifier circuit and then applies the amplified voltage to a second terminal of the piezoelectric actuator through resistors. The feedback circuit amplifies a difference between voltages at respective ends of the resistor and supplies the amplified difference to the amplifier circuit.

Abstract: A piezoelectric fan includes a blade that is joined to a piezoelectric oscillator that bends in response to an application of a voltage, and the blade of the piezoelectric fan is arranged to swing in a space between neighboring heat dissipating fins of a heat sink. The formation of a hole in the blade increases the amplitude of the blade and also improves the sweep effect of sweeping high-temperature air in the vicinity of the wall of the heat dissipating fin, and thus, improves the cooling capability of the piezoelectric fan.

Abstract: A measurement error correcting method and electronic component characteristic measuring device capable of accurately coping with an electronic component which includes nonsignal line ports and whose electrical characteristics are changed by a jig. The method includes the steps of measuring an electrical characteristic, with correcting-data-acquisition samples mounted on a test jig enabling measuring nonsignal line ports, and the samples mounted on a reference jig; measuring a through device in which a signal line port and a nonsignal line port are electrically connected to each other; determining a numerical expression for calculating, from results of measurement on the test jig, an estimated electrical characteristic value obtained on the reference jig; measuring an arbitrary electronic component, on the test jig; and calculating the estimated electrical characteristic value obtained on the reference jig.

Abstract: A piezoelectric fan device includes four piezoelectric fans that are arranged side-by-side in their width direction, and ends of the piezoelectric fans opposite to other ends in which the blades extend are coupled side-by-side and supported by a support. The piezoelectric fans include piezoelectric vibrators arranged to flexurally vibrate when a voltage is applied thereto and blades coupled to the piezoelectric vibrators such that the blades can be excited by the piezoelectric vibrators. Two central piezoelectric fans are driven in the same phase and the other two piezoelectric fans are driven in the opposite phase by a voltage applying device. Accordingly, not only vibrations of the centroid acting on the support but also moments about three axes are cancelled out.

Abstract: A piezoelectric fan includes a piezoelectric vibrator that vibrates in a bending mode when a voltage is applied thereto and a plurality of parallel or substantially parallel blades connected to or integrated with the piezoelectric vibrator. The blades are arranged between heat-radiating fins of a heat sink such that the blades bend parallel or substantially parallel to side surfaces of the heat-radiating fins. A joint that connects the blades to each other is disposed at free ends in a longitudinal direction of the blades. When the blades are excited by the piezoelectric vibrator and warm air between the heat-radiating fins is blown, the joint prevents the blades from twisting.

Abstract: A piezoelectric pump includes a piezoelectric element, an intermediate plate, and a vibrating plate. The piezoelectric element has a substantially flat plate shape. The intermediate plate is bonded to a principal surface of the piezoelectric element and applies a residual stress in a compressive direction to the piezoelectric element. The vibrating plate is bonded to the intermediate plate such that the vibrating plate faces a principal surface of the piezoelectric element and receives a residual stress in a compressive direction from the intermediate plate. In addition, the vibrating plate defines a portion of a wall surface of a pump chamber having an open hole. A fluid passage is provided in the piezoelectric pump. The fluid passage communicates with the outside of the chamber at one end thereof, and communicates with the pump chamber through the open hole at the other end.

Abstract: An electronic-component high-frequency characteristic error correcting method for allowing a calibration work to be performed on a two-terminal impedance component using the same correction-target measuring system as that used in actual measurement. At least three correction data acquisition samples having different high-frequency characteristics are measured by a reference measuring system and an actual measuring system. An equation for associating the value measured by the actual measuring system with the value measured by the reference measuring system using an error correction coefficient of a transmission line is determined. A given electronic component is measured by the actual measuring system. An estimated high-frequency characteristic value of the electronic component obtained when the electronic component is measured by the reference measuring system is calculated using the determined equation.

Abstract: A measuring method and measurement system that includes a signal source that applies a signal to a device under test, a scalar measuring instrument that measures a reflected wave reflected from the device under test or a transmitted wave transmitted through the device under test as a scalar value, and a superimposing signal system that superimposes three different vector signals whose relation values are specified in advance on the reflected wave or the transmitted wave of the device under test. The three vector signals are superimposed on the reflected wave or the transmitted wave of the device under test, and the superimposed signals are each measured as a scalar value by the electric-power measuring instrument. The three measured scalar values are converted into a single vector value using the specified relation values of the three vector signals, thereby obtaining a transmission coefficient of the device under test.

Abstract: A piezoelectric micro-blower capable of efficiently conveying compressive fluid without use of a check valve and ensuring a sufficient flow rate. The micro-blower has a blower body with a first wall and a second wall. Openings are formed in the respective walls and face a center of a diaphragm. An inflow path allowing the openings to communicate with the outside is formed between the walls. By applying a voltage to a piezoelectric element to cause the diaphragm to vibrate, a part of the first wall close to the first opening vibrates. Thus, gas can be drawn from the inflow path and discharged from the opening in the second wall.

Abstract: A fluid conveyance device includes a substrate, and a disk-shaped piezoelectric element arranged in a bendable manner on the substrate. A plurality of substantially circular concentric segment electrodes are provided on the piezoelectric element, and are provided with voltages with phases that are shifted. A wavy ring deformation is thus produced on the piezoelectric element. A pocket produced between the piezoelectric element and the substrate is moved in a radial direction so as to convey a fluid from an outer substantially circular portion to a central portion and to discharge the fluid from the central portion.

Abstract: A piezoelectric micro-blower capable of efficiently conveying compressive fluid without use of a check valve and ensuring a sufficient flow rate. The micro-blower has a blower body with a first wall and a second wall. Openings are formed in the respective walls and face a center of a diaphragm. An inflow path allowing the openings to communicate with the outside is formed between the walls. By applying a voltage to a piezoelectric element to cause the diaphragm to vibrate, a part of the first wall close to the first opening vibrates. Thus, gas can be drawn from the inflow path and discharged from the opening in the second wall.

Abstract: A blower body is provided with a first wall and a second wall, and openings are provided in the walls at positions facing the approximate center of a diaphragm. An inflow passage that allows the openings to communicate with the outside is arranged between the two walls. When the diaphragm is vibrated in response to a voltage applied to a piezoelectric element, the first wall vibrates near the opening and sucks in air from the inflow passage so that the air can be ejected from the opening. A plurality of branch passages which provide sound absorption are connected to an intermediate section of the inflow passage so as to prevent noise generated near the opening from leaking from an inlet.

Abstract: A piezoelectric pump having a first opening in a center portion of a pump body, and a second opening apart from the center. An outer peripheral portion of a metal diaphragm is fixed to the pump body, and a piezoelectric element having a size that covers the first opening and does not cover the second opening is bonded to a back center portion of the diaphragm. By applying a voltage near the resonance frequency to the piezoelectric element, a portion of the diaphragm opposing the first opening and a portion of the diaphragm opposing the second opening are bent in opposite directions so that fluid is drawn in from one of the first opening and the second opening and is discharged from the other opening. Such a piezoelectric pump can increase the discharging pressure, and can reliably discharge the fluid even under a condition where the pressure on the discharging side is high.

Abstract: A piezoelectric pump capable of generating a large displacement at a central portion of a piezoelectric element even when a driving voltage is relatively low and preventing short-circuits caused by migration. The piezoelectric pump includes a pump body with a pump chamber, and a piezoelectric element that closes the pump chamber. The central area and the peripheral area of the piezoelectric element are bent in opposite directions by applying voltages to the piezoelectric element so that the volume of the pump chamber is changed. The piezoelectric element is a laminate including a plurality of piezoelectric layers with electrodes interposed therebetween. The central area and the peripheral area of each piezoelectric layer are polarized opposite to each other in the thickness direction, and the electrodes are formed such that voltages in the same direction in the thickness direction are applied to the central area and the peripheral area of each piezoelectric layer.

Abstract: A method of processing a ceramic capacitor includes a first step of applying a DC voltage to a ceramic capacitor by a first DC voltage source, and a second step of applying a DC voltage by a second DC voltage source to generate in the ceramic capacitor a polarization in a direction opposite to a direction of a polarization generated by the application of the DC voltage in the first step, thereby reducing electric charge remaining in the ceramic capacitor.

Abstract: A piezoelectric micropump in which a pump chamber is isolated by a diaphragm. A piezoelectric element is disposed on a back surface of the diaphragm, and the diaphragm is deformed by bending deformation of the piezoelectric element to change the volume of the pump chamber and transport fluid in the pump chamber. A support member for supporting a back surface of the piezoelectric element is provided so that the support member inhibits bending of a peripheral portion of the diaphragm in a reverse direction. The support member thus prevents the piezoelectric element from being floated. Accordingly, the displacement of the piezoelectric element can be reliably transmitted as the change in volume of the pump chamber, thereby enhancing the fluid transportation performance.

Abstract: A micropump having a diaphragm portion, a valve portion of an intake-side check valve, and a valve portion of a discharge-side check valve formed in a single elastic-member sheet. A piezoelectric actuator is attached onto a back surface of the diaphragm portion. The elastic-member sheet is sandwiched between a first case member and a second case member, the elastic-member sheet providing sealing between both case members. A vibration chamber is defined between the elastic-member sheet and the first case member, the vibration chamber housing the piezoelectric actuator. A pump chamber is defined between the elastic-member sheet and the second case member.

Abstract: A coil antenna structure includes a first magnetic component extending in the thickness direction of a tabular primary casing. A second magnetic component and a third magnetic component, which are magnetically connected to the first magnetic component, are disposed on the first principal surface side and the second principal surface side of the primary casing, respectively. The first magnetic component is provided with a coil component surrounding it. In this manner, a U-shaped magnetic path is provided at an end portion of the primary casing so as to detour around a substrate defining an internal conductor. Likewise, a U-shaped magnetic path including fourth to sixth magnetic components is provided in a secondary casing defining a clamshell type casing together with the primary casing so as to detour around a substrate defining as an internal conductor.

Abstract: A signal conductor whose first end is an open end, and a ground conductor are connected to associated measurement ports of a network analyzer. A short standard is connected between the signal conductor and the ground conductor at least three points in the longitudinal direction of the signal conductor, and electrical characteristics are measured, thereby calculating error factors of a measurement system including a transmission line. An electronic device to be measured is connected between the signal conductor and the ground conductor, and an electrical characteristic is measured. The error factors of the measurement system are removed from the measured value of the electronic device to be measured, thereby obtaining a true value of the electrical characteristic of the electronic device. Accordingly, a highly accurate high-frequency electrical characteristic measuring method, using a reflection method, that is not affected by connection variations can be implemented.