43results about How to "Small frequency change" patented technology

A method of drying an object comprising, providing an object into an RF cavity; applying broadband RF energy to the object in controlled manner which keeps the object within a desired temporal temperature schedule and within a desired spatial profile; and terminating the drying when it is at least estimated that a desired drying level is achieved.

A surface acoustic wave device includes: a quartz substrate; and at least a single-type IDT electrode provided on a surface of the quartz substrate for exciting a Rayleigh surface acoustic wave in the upper limit mode of the surface acoustic wave stop band with the following relationships satisfied;φ=0°, 110°≦θ≦140°, and 38°≦|ψ|≦44°, when the quartz substrate cut angles and the surface acoustic wave propagation direction are represented by Euler angles (φ, θ, ψ), and wherein the electrode thickness relative to wavelength set such thatH / λ≧0.1796η3−0.4303η2+0.2071η+0.0682, with the thickness of the IDT electrode defined as H, the width of an electrode IDT finger defined as d, the pitch between the electrode fingers of the IDT electrode as P, the wavelength of the surface acoustic wave as λ, and where η=d / P.

The invention discloses an online analyzing method for grid forced power oscillation caused by internal disturbance of a power plant and relates to the field of power system operation and control. The method is mainly used for judging whether the grid forced power oscillation is caused by internal periodical disturbance of the power plant. In actual operation of a grid, the forced power oscillation caused by generator disturbance is the most common oscillation mode, but whether grid oscillation is caused by the internal disturbance of the power plant where the grid is connected or by the disturbance at the grid end is difficult to judge directly through the characteristics of oscillation amplitude, frequency and the like. Therefore, the method is provided to identify measured data parameters of the power plant connected into grid nodes based on FFT (fast Fourier transform) and conduct energy flow phase difference analysis to judge whether the grid oscillation is caused by the internal disturbance of the power plant where the grid is connected. By means of the method, judgment can be conducted directly at a measuring terminal, and the method is simple in calculation and high in analyzing speed and has good actual application value.

A transversally coupled double-mode SAW filter using a surface acoustic wave has two SAW resonators which have curtain-like electrodes and a pair of reflectors on both side thereof, respectively, and which are disposed in parallel on a piezoelectric flat plate in the propagation direction of the surface acoustic wave. The curtain-like electrodes of the SAW resonators have a first bus bar of electrically positive electrode which extends in the propagation direction of SAW and second and third bus bars of electrically negative electrode which extend in parallel on both sides of the first bus bar. The first bus bar has multiple electrode fingers of electrically positive electrode which face the second and third bus bars on both sides thereof and which extend in a direction perpendicular to the propagation direction of SAW so as to suitably have a space of lambd / 2, lambd being the wavelength of the surface acoustic wave, and a width of lambd / 4. The second and third bus bars have multiple electrode fingers of electrically negative electrode which correspond to the electrode fingers of electrically positive electrode, face the first bus bar and extend in a direction perpendicular to the propagation direction of SAW so as to similarly have a space of lambd / 2 and a width of lambd / 4. Thereby, the curtain-like electrodes are constituted to invert the direction of driving field by 180° with the first bus bar therebetween, and to enable making the passband width sharply broader than before by use of the frequency difference between excited primary symmetric mode and primary anti-symmetric mode.

A surface acoustic wave device includes: a quartz substrate; and at least a single-type IDT electrode provided on a surface of the quartz substrate for exciting a Rayleigh surface acoustic wave in the upper limit mode of the surface acoustic wave stop band with the following relationships satisfied;φ=0, 110°≦θ≦140°, and 38°≦|ψ|≦44°, when the quartz substrate cut angles and the surface acoustic wave propagation direction are represented by Euler angles (φ, θ, ψ), and wherein the electrode thickness relative to wavelength set such thatH / λ≧0.1796η3−0.4303η2+0.2071η+0.0682, with the thickness of the IDT electrode defined as H, the width of an electrode IDT finger defined as d, the pitch between the electrode fingers of the IDT electrode as P, the wavelength of the surface acoustic wave as λ, and where η=d / P.

A compact resonator has a wide bandwidth and a small variation of the specific vibration frequency. The resonator is a thin film tuning-fork type inflection resonator in which a thin film made of a piezoelectric material is formed on a substrate on which a lower electrode is formed, and an upper electrode is formed on the piezoelectric thin film.

The invention relates to an isolation DC-DC power supply module meeting the GJB181 standard. The isolation DC-DC power supply module comprises a fuse tube, an EMI filter circuit, an anti-reverse-connection protection circuit, a transient peak pulse bleeder circuit, a surge current suppression circuit, a Buck-Boost circuit and an LLC resonant conversion circuit which are connected in turn. The self-restoring type fuse tube is selected so that input overcurrent can be avoided; the positive and negative surge peak voltage is controlled to the acceptable degree of the DC-DC switching power supplyby the transient peak pulse bleeder circuit; the problem of excessively high surge current can be solved by the active surge current suppression circuit; the Buck-Boost wide voltage circuit handles the input overvoltage / undervoltage situation; and the LLC resonant converter topology realizes soft switching so that the overvoltage stress of the switch MOSFET can be reduced and the stored electromagnetic energy can be increased, and the switching frequency and efficiency of the converter can be effectively enhanced.

The invention discloses a high-precision relaxation oscillator capable of being trimmed and regulated. The high-precision relaxation oscillator comprises an oscillation generator, a high-precision current bias generator, a voltage regulator and a driving and output part, wherein the high-precision current bias generator provides the bias for a constant current source in the oscillation generator, the voltage regulator generates two threshold levels for a comparator in the oscillation generator, and the oscillation generator utilizes capacitor charging and discharging to generate oscillation waveform to be provided for the driving and output part. The high-precision relaxation oscillator has the positive effects that through the realization of the high-precision bias current and the trimming and regulation of a register of the comparison threshold levels, the process deviation and the oscillator frequency change during the power supply voltage or environment temperature change can be reduced, and the value after the frequency modification can meet the designed precision requirements.

The embodiment of the invention provides an image display device and an image display method, relating to the field of display devices, and being capable of increasing the charging time and reducing the switching frequency of drive data in the process of driving the display device. The image display method is used for driving the display device, the display device comprises m rows and n lines of combined pixels, each combined pixel comprises a first line of sub-pixels and a second line of sub-pixels (the second line of sub-pixels is arranged below the first line of sub-pixels, and constitutes the combined pixel with the first line of sub-pixels), a first grid lead is connected with the first line of sub-pixels, a second grid lead is connected with the second line of sub-pixels, and while the display device is driven in a 2D (two-dimensional) image mode, the first lines of sub-pixels and the second lines of sub-pixels of each line of combined pixels all receive display data; and when the display device is driven in a 3D (three-dimensional) image mode, the first lines of sub-pixels of each line of combined pixels receive data, and the other liens of sub-pixels of each line of combined pixels do not receive data. The method disclosed by the embodiment of the invention is applied to the driving of image display devices.

A lamb wave type high frequency device includes: an interdigital transducer (IDT) electrode having an electrode finger interdigitated therein; a pair of reflectors having an electrode finger and being disposed at both sides of a propagation direction of a lamb wave excited by the IDT electrode; and a piezoelectric substrate on a surface of which the IDT electrode and the reflectors are disposed, wherein a pitch of the electrode finger of the IDT electrode and a pitch of the electrode finger of the reflectors are different from one another.

A piezoelectric shear resonator has a substantially rectangular-column piezoelectric element that excites a shear-vibration mode and that has opposing substantially rectangular shear strain surfaces. The shear strain surfaces each have an aspect ratio at which the electromechanical coupling factor reaches substantially a maximum value. When the vertical dimension of the shear strain surfaces is D and the horizontal dimension thereof is Le, the aspect ratio Le / D is expressed by Le / D={α·(S44E / S33E)1 / 2+β}±0.3, where S44E and S33E are elastic compliances, α=0.27·n+0.45, β=1.09·n+0.31, and n is a positive integer.

The invention discloses a measuring system of relative position of a laser mode and an aperture and a measuring method thereof, and mainly solves the disadvantage of low measurement precision of present systems. The whole system comprises a laser (1), an optical system (15), a resonator to be measured (6), a spectroscope (7), a total reflective mirror (8), an image acquisition and data acquisition system (16), a main control computer (13), and a piezoelectric ceramics driver (14); the piezoelectric ceramics driver drives the laser to output laser; the optical system is adjusted to allow the laser outputted by the laser to be coupled to the resonator to be measured; the laser outputted by the resonator to be measured are divided into two paths by the spectroscope and the total reflective mirror; the two-path laser is collected and transmitted to the main control computer by the image acquisition and data acquisition system; the main control computer processes images of the aperture andthe laser mode by using a high-precision image processing algorithm, and calculates the central coordinates of the aperture and the laser mode respectively. The invention has the advantages of synchronous CCD camera acquisition and sawtooth wave signals, and high measurement precision, and is applicable to the high-precision automatic regulation of the laser.

The invention discloses a clock calibration method and device. The clock calibration method comprises the following steps of: receiving a standard second pulse signal; acquiring a first local second pulse signal; acquiring a first phase difference between the first local second pulse signal and the standard second pulse signal; and acquiring a threshold value of a filtering phase difference according to the first phase difference, and filtering an interference signal in the standard second pulse signal by utilizing the threshold value of the filtering phase difference. By means of the clock calibration method, the threshold value of the filtering phase difference for filtering out the interference signals can be automatically adjusted, the influence of the interference signals is reduced,and the stability of the local clock is improved.

A resonator includes a resonator element including a substrate gradually increasing in thickness from an outer edge toward a center, excitation electrodes respectively disposed on both principal surfaces of the substrate, and a pair of electrode pads electrically connected to the excitation electrodes, disposed on at least one of the both principal surfaces, and disposed on one end side of the substrate, and a second substrate as a base, the pair of electrode pads are bonded to the second substrate via respective first bonding members, two places of the other end of the substrate on the opposite side to the one end are bonded to the second substrate via respective second bonding members, and a distance S1 between the two first bonding members, and a distance S2 between the two second bonding members fulfill S1<S2.

The invention discloses an automatic distinguishing system for an impact-cone concrete pile foundation soil layer kinds and a work method of the automatic distinguishing system. The system comprises a frequency collector, a wireless digital sensor and a computer. The frequency collector transmits data to the computer through the wireless digital sensor. The frequency collector and the wireless digital sensor are arranged in an impact-cone concrete pile machine heavy hammer. The automatic distinguishing system can accurately obtain the actual soil layer kind according to comparison between the field punching frequency and a standard soil layer database in the computer, the problem that when constructors at the current stage subjectively assess the soil layer kind, the kind of the soil layer cannot be accurately obtained is solved; and meanwhile, the construction design can be checked or the initial design can be changed, the project quality is improved, and the project cost is reduced. By means of the automatic distinguishing system, the thickness of the operation soil layer can be accurately measured, the construction error caused by the uneven change of the construction field soil layer and the insufficient bearing layer thickness and bearing layer thickness measured during lofting are avoided, and construction safety is guaranteed.

The invention discloses a method for improving a coaxial-cavity dielectric oscillator. The method is characterized by comprising the following steps: reducing the output frequency of the coaxial-cavity dielectric oscillator to the half in a normal state; accessing the reduced output frequency to a high-pass filter and selecting second harmonics of the reduced output frequency; increasing the length of a resonator by three times than a quarter wavelength mode. The method has the advantages that the adjustment is more convenient and the operability is higher; the frequency variation is small, so that the difficulty in circuit debugging is greatly reduced.

To provide a piezoelectric part manufacturing method by which a frequency change before and after soldering to a substrate is small, and by which a time can be reduced until a frequency becomes stable. A piezoelectric part manufacturing method includes a process of soldering lead terminals 20-22 to terminal electrodes of a piezoelectric element 1, a process of obtaining piezoelectric parts by spreading an armoring resin 30 around the piezoelectric element 1 in which the lead terminals are soldered and by curing the resin, a process of performing heat aging to the piezoelectric parts after curing the resin, a process of leaving the parts at room temperature until the characteristic of the piezoelectric element 1 becomes stable after the heat aging, and a process of selecting the parts by measuring the characteristic of the piezoelectric element 1 after leaving the parts at room temperature. By performing the heat aging at a stage of a completed product, a frequency change upon flow soldering at a subsequent process is made small, and a frequency is promptly made stable.(C)2004,JPO.

The invention discloses an inverter power supply device. The circuits sequentially consist of a low frequency oscillator circuit, a circuit consisting of a pulse distributor, a pulse duty ratio control switch, a high frequency oscillator and two paths of power control switches, a circuit consisting two distributors and a booster transformer, a reversion and filtration circuit, a voltage sampling circuit, a voltage stabilization and amplification circuit, an overload protection circuit, a fault protection circuit and a shell, wherein the reversion and filtration circuit is formed by serially connecting two ends of two inversely and parallelly connected silicon-controlled rectifiers first with coupled coils and then with parallelly connected capacitors. In the device, frequency-division technology and pulse width program modulation circuit as well as power switch tubes and a booster transformer circuit are adopted, high-frequency pulse width grows from small to big and from big to smalland finally to zero , two sets of power switch tubes operate alternately, and a pulse width-variable high-frequency voltage of which the polarity varies at a speed of 50Hz on the secondary side of thetransformer. The inverter power supply device is a low-frequency inverter power supply which is high in voltage stabilization performance, small in frequency variation and large in output power and has an output waveform of sine waves.

The invention provides a compressor. The compressor comprises a linear motor and a compression mechanism driven by the linear motor. The linear motor comprises a driving mechanism and a coupling shaft, wherein the coupling shaft comprises a first end part and a second end part, the first end part and the second end part are connected into a whole, the first end part is embedded in the driving mechanism, and one end of the second end part is connected with the compression mechanism. A conical spring is arranged on the outer periphery of the second end in a sleeving mode, and the conical springis positioned between the driving mechanism and the compression mechanism. The compressor has simple structure and simplified control and improves the compressor efficiency.

The invention provides a fast frequency response distributed coordination control method and system for a series-parallel wind and light micro-grid. The method comprises the following steps: acquiring operation state data of each distributed energy source; obtaining total optimal power input according to a model predictive control algorithm by using the obtained operation state data; and distributing total optimal power input on all distributed energy sources in the micro-grid through the maximum rated power and the charging state of the given time. The inertia of the wind energy or solar energy photovoltaic power supply AC micro-grid with a plurality of distributed converter interfaces is obviously improved, and when the power drawn by the load suddenly changes, the frequency change of the system is reduced.

The invention discloses a high-power synchronous rectification high-frequency switching power supply. The high-power synchronous rectification high-frequency switching power supply comprises a case, afirst conductive busbar, a second conductive busbar, transformers, a main control circuit, a three-phase input rectifier stack, a rectifier bridge module circuit board, a chopping module and a secondrectifier module. The first conductive busbar is positioned at the upper portion of the second conductive busbar, the first conductive busbar and the second conductive busbar are inserted in the casein parallel and in a staggered manner, one end of a conductive double-hole busbar is connected with the main control circuit, the other end of the conductive double-hole busbar extends out of the case, the transformers are fixedly arranged at the lower portion of the first conductive busbar in the extension direction of the first conductive busbar, the second rectifier module is arranged on the first conductive busbar and the transformers, and the chopping module, the three-phase input rectifier stack and the rectifier bridge module circuit board are arranged on the second conductive busbar.The switch power supply provided by the invention has the advantages of simple and reasonable arrangement of all parts, a compact structure, convenience in installation, disassembly and maintenance and good heat dissipation effect.

A crystal unit according to this disclosure includes an IT-cut round crystal element (1) supported at two points on an outer periphery portion of the IT-cut round crystal element. A straight line connecting these two points has a rotation angle in plane of -12 degrees to +4 degrees or +60 degrees to +80 degrees from Z'' axis of a double-rotation. Notched portions are included at the support position of the crystal element and are clamped to the a slit formed on the support to support the crystal element.

The invention is applicable to the technical field of crystal oscillators, and provides a frequency compensation system of a crystal oscillator with amplitude phase compensation. The system comprisesan acceleration sensor, an acceleration compensation circuit and a phase amplitude compensation circuit; the acceleration of the crystal oscillator is detected through the acceleration sensor, and then the acceleration voltage signal is subjected to acceleration compensation through the acceleration compensation circuit to obtain acceleration compensation voltage; finally, the amplitude and phasecompensation is carried out on the acceleration compensation voltage through the phase amplitude compensation circuit to obtain a final compensation voltage, so the final compensation voltage can reduce the amplitude and phase deviation of a voltage signal when the acceleration sensor monitors the vibration intensity of the crystal oscillator, thereby reducing the frequency change of the crystal oscillator, enlarging the frequency compensation range of the crystal oscillator, and optimizing the near-end dynamic phase noise of the crystal oscillator.

The invention concerns a novel bulk acoustic wave (BAW) resonator design and method of manufacturing thereof. The bulk acoustic wave resonator comprises a resonator portion, which is provided with at least one void having the form of a trench which forms a continuous closed path on the resonator portion. By manufacturing the void in the same processing step as the outer dimensions of the resonator portion, the effect of processing variations on the resonant frequency of the resonator can be reduced. By means of the invention, the accuracy of BAW resonators can be increased.

The invention discloses a high-precision relaxation oscillator capable of being trimmed and regulated. The high-precision relaxation oscillator comprises an oscillation generator, a high-precision current bias generator, a voltage regulator and a driving and output part, wherein the high-precision current bias generator provides the bias for a constant current source in the oscillation generator, the voltage regulator generates two threshold levels for a comparator in the oscillation generator, and the oscillation generator utilizes capacitor charging and discharging to generate oscillation waveform to be provided for the driving and output part. The high-precision relaxation oscillator has the positive effects that through the realization of the high-precision bias current and the trimming and regulation of a register of the comparison threshold levels, the process deviation and the oscillator frequency change during the power supply voltage or environment temperature change can be reduced, and the value after the frequency modification can meet the designed precision requirements.