454results about How to "Suppress resonance" patented technology

The invention discloses a combined vibration damper of a screw drill complete machine test-bed and a manufacturing method thereof. The combined vibration damper comprises a vibration attenuation base which comprises a loading system base, a first clamping system base and a second clamping system base, wherein the loading system base is arranged on an equipment foundation in a rigidity way; the first clamping system base and the second clamping system base are connected into a whole through a bolt and are arranged on the equipment foundation through a rubber vibration attenuation block; an interval of 30-50 mm is reserved between the loading system base and each clamping system base; the first clamping system base and the second clamping system base are respectively internally provided with a plurality of cubic cavities with an equal size; the volume of each cubic cavity is 0.1-0.2 cubic meter; discrete type balance weight sand is respectively filled into the cubic cavities, and the filling efficiency is 80-90 %; and the weight of the balance weight sand is 25-35 % of the total weight of the whole device. The test-bed is capable of restraining resonance and testing precisely in the testing process by the combined vibration damper, and the usage precision of surrounding working devices is not affected.

A locking device for a lock cylinder (12) has an electronically controlled inhibiting element (2), which in an inhibit position (x.sub.S) blocks movement of a rotor (1) relative to a stator (6) and frees the rotor (1) in a free position (x.sub.F). A drive (9) exerts a working force (F.sub.A) on the inhibiting element (2), by which inhibiting element (2) can be reversibly transferred from the inhibit position (x.sub.S) into the free position (x.sub.F) and vice versa. A guide (52-57) is connected to the drive (9) and, at least outside the free position (x.sub.F), clearly defines the position of the inhibiting element (2). A restoring device (3) exerts a restoring force (F.sub.R) directed away from the free position (x.sub.F) on the inhibiting element (2), when that element is between the free position (x.sub.F) and a rest position (x.sub.O). In the rest position (x.sub.O) and in positions between the rest position (x.sub.O) and the free position (x.sub.F), the inhibiting element inhibits movement of the rotor (1). The locking device is resistant to external, undesired vibration and / or shock effects or magnetic action.

In a molded motor having a motor frame molded by covering a stator composed by a straight core with a molding resin, the straight core has a stack of laminas each having a plurality of tees projecting from one long side of a belt-shaped back yoke and a V-shaped cut formed between every two adjoining tees along the back yoke and on its side from which the tees project. The straight core has an insulating layer formed by pre-molding from an insulating resin on its portions excluding at least the inner periphery of each tee. The straight core also has a winding formed about each tee having the insulating layer formed thereon. The stator is formed by bending the straight core at the cuts into an arcuate or annular shape, and joining the opposite ends of the back yokes to each other by welding or adhesion.

The invented optical-fibre grating vibration sensor is characterized by that it utilizes a demodutation grating and a sensing grating and makes them be series-connected together, and respectively makes them be stuck on a main beam and an auxiliary beam, two beams are made of identical material and have identical heat expansion coefficient, so that their central wavelengths can be synchronously shifted with temperature, therefore they have automatic temperature compensation function so as to implement matching filter demodutation. Said invention utilizes the detection of light intensity change of sensing grating reflecting light to monitor the parameters of vibration frequency and vibration amplitude of monitored body, finally utilizes computer or single-chip computer to make analysis and processing of body vibration frequency spectrum.

The invention discloses a multi-converter parallel circulating current restraining method with quick and reactive support. For a single converter, drop control calculation is adopted, and an output reference voltage of the converter is synthesized; resistance-capacitance virtual complex impedance is guided in the output current feedback of the inverter, so that the equivalent output impedance of the converter is of resistance-capacitance performance, wherein capacity component realizes quick and reactive support of the inverter, the resonant vibration between the output impedance of the inverter and the impedance of an electrified wire fence is restricted through resistance component, and fundamental wave circulating currents and harmonic circulating currents are reduced; and through a voltage current control loop, the stability and control precision of a system are further strengthened, and accurate distribution of power is realized. According to the method, the problem that the existing method is not high in power equipartition precision, relatively large in circulating current and relatively large in voltage fluctuation, and the method can be applied to power generation parallel control systems of industrial special power supply and new power supply.

The invention discloses a current source type PWM (Pulse-Width Modulation) rectifier and a grid-connected control method based on a virtual resistor. A grid-connected rectifier consists of commercial power, an alternating-current filtering inductor, an alternating-current filtering capacitor, a three-phase current source type rectifier, a direct-current inductor, a direct-current capacitor and a digital controller. Sampled alternating-current filtering capacitance voltage is transmitted to a microprocessor to perform digital phase locking, and after phase locking is finished, the alternating-current filtering capacitance voltage and phase are transmitted to an alternating-current controller. The alternating-current controller consists of a coordinate converter, a virtual impedance regulator and a divider. The coordinate converter converts the three-phase alternating-current filtering capacitance voltage into the voltage under a two-phase static coordinate system, after the voltage is regulated by the virtual resistance regulator, current passing through a virtual resistor is obtained, control amount of the alternating-current side is obtained through the divider, the control amount is superposed on the control amount on the direct-current side, a driving signal obtained through a PWM generator is transmitted to a driving plate, and after the signal is amplified by the driving plate, the connection and disconnection of a three-phase current source type rectifying bridge switch are controlled. The control effect of the virtual resistance regulator in the alternating-current controller is equivalent to the control effect that a resistor is directly connected in parallel on an alternating-current capacitor, so that oscillation can be effectively damped, loss is not caused, and ultraharmonics in grid-connected current can be effectively inhibited. The rectifier is high in dynamic response speed, stable in dynamic response and high in power factor, the total harmonic distortion rate of the grid-connected current is low, and the method can be applied to an uninterruptible power supply.

The invention relates to a magnesium alloy integrally cast sound box which comprises a sound box body (1), wherein, a high-frequency loudspeaker (10), a medium / low-frequency loudspeaker (11) and an electronic frequency divider (7) are installed in the sound box body (1), the sound box body (1) is connected with a wiring post (8) through a wire, and a sound absorption layer (9) is arranged on the inner wall of the sound box body (1). The sound box body (1) is a magnesium alloy integrally cast structure, and a high-frequency loudspeaker hole (3) is arranged at the upper part of the sound box body (1); a medium / low-frequency loudspeaker hole is arranged at the middle part of the sound box body (1); and a sound-wave reversed phase hole (5) is arranged at the lower part of the sound box body (1). The manufacturing method comprises the following steps: the magnesium alloy is melted in a smelting furnace in the air or under the protective atmosphere, and the casting core can adopt a wooden core, metal core, and the like, by various molding and casting processes such as sand casting, metal mold casting, and the like; the magnesium alloy adopted in the method comprises the following component of Mg-X alloy, wherein, X can be an element such as Ni, Zr, Al, Cu, and the like, and one or more of the elements can be adopted to be combined with Mg to form binary, ternary or polynary magnesium alloy; and the sound box is characterized in that the seamless sound box body can be conveniently in any shape and complex structure. The invention has the advantages of simple structural process, low manufacturing cost and good tone color.

A double-wall structure (1), comprising plate-like bodies (2) and (3) disposed oppositely to each other to form an inner room (4) therebetween, peripheral members (5) disposed so that the inner room (4) can be completely or approximately closed, and perforated plates (13) with a large number of holes (8) disposed between the plate-like bodies facing each other. The double-wall structure is characterized in that an air layer (A) is interposed between the perforated plates and the peripheral members. Thus, since the double-wall structure can suppress the deterioration of a sound reduction index for sound with specific frequencies, it can stably develop sound insulation performance for sound with the various frequencies.

A method and a structure for suppressing resonance in an anti-shake lens focusing module are disclosed. The resonance suppressing method includes the steps of providing a lens focusing structure having a first movable part and a first immovable part; providing an anti-shake structure having a second movable part and a second immovable part; providing at least one shock-absorbing material between the first movable and immovable parts as well as between the second movable and immovable parts; and using the shock-absorbing material to absorb any vibration caused by movements of the first and the second movable part, so as to suppress any resonance possibly generated due to the movements of the first and the second movable part.

A hybrid power device is formed of a normally-on type SiC-JFET and a normally-off type Si-MOSFET, which are connected in cascode with a source of the SiC-JFET and a drain of the Si-MOSFET being connected to each other thereby forming a hybrid power FET. A gate of the SiC-JFET and a source of the Si-MOSFET are connected via a switching speed regulating resistor. A capacitor is connected to the switching speed regulating resistor in parallel to control a switching speed to a first speed in a former part of the switching period of the hybrid power FET and to a second switching speed in a latter part of the switching period. The second switching speed is lower than the first switching speed.

A motor controller having a damper that dampens resonance in a motor drive of a common mode filter to prevent it from becoming over excited by operation of the motor drive at a resonant frequency of the common mode filter. The damper is connected to an output feeder line of a motor drive in the motor controller and provides a common mode path to ground for the common mode filter. Thus, even if the motor drive is operating at a resonant frequency of the common mode filter, the resulting resonance in the common mode filter is attenuated by rather than amplified by the common mode filter, thereby preventing the common mode filter from excessive excitation.

To provide a tread pattern of a pneumatic tire for heavy load enhancing both low noise performance and on-snow performance. Longitudinal length L4C of a central block, longitudinal length L4M of an intermediate block and longitudinal length L4S of an outer block, i.e., circumferential distances of respective tires between the most projecting end points on both sides of a tire circumferential direction of the central, intermediate and outer blocks (4) are defined; and lateral length W4C of the central block, lateral length W4M of the intermediate block and lateral length W4S of the outer block, i.e., tire axial distances between the most projective terminals at both sides in a tire axial direction of the respective central, intermediate and outer blocks (4) are defined. A longitudinal length ratio of the respective blocks is made to (L4S / W4S)<(L4M / W4M)<(L4c / W4C), 1.50 B60C 11 / 117 4 15 2 2006 / 7 / 31 1907738 2007 / 2 / 7 100473547 2009 / 4 / 1 2009 / 4 / 1 2009 / 4 / 1 Sumitomo Rubber Industries, Ltd. Japan Takahashi Nobugo xu qian luo yunpo 11227 Japan 2005 / 8 / 4 2005-226922

A power converter includes a rectifier section, an inverter section, a capacitance element connected between inverter section input ends, an inductance element forming part of an LC filter with the capacitance element, a voltage detector detecting an inductance element voltage, and a controller controlling the inverter section based on the detected voltage. The LC filter has a resonance frequency set such that ripple current components contained in DC current outputted from the rectifier section passes through, and current components of a frequency equal to a carrier frequency of the inverter section are dampened. The controller controls the inverter section so that a transfer characteristic of input voltage of the inverter section versus the DC voltage from the rectifier section becomes a damping characteristic given by a phase lead element and a second-order lag element connected in series, and a damping coefficient of the transfer characteristic is set larger than 1.

An electric power steering system for a vehicle works to determine an assist command based on steering torque to produce assist torque through an electric motor for assisting in turning a steering wheel of the vehicle, also determines a tracking command for producing automatic steering torque which brings a value of a given physical quantity associated with steering of the vehicle into agreement a target value, and calculates a vibration correction command for use in producing vibration correction torque which suppresses vibration of the steering torque which arises from output of the torque from the electric motor based on a transfer characteristic of transmission of the output of torque from the electric motor as a part of the steering torque through the steering mechanism. A motor driver works to actuate the electric motor based on the sum of the assist command, the tracking command, and the vibration correction command.

Pressure detecting apparatus includes: a housing; a pipe extending from one end of the housing and having an elongated shape; and a pressure sensitive element for detecting pressure and outputting a signal corresponding to the pressure. The pipe includes a top end capable of receiving the pressure. The pressure sensitive element is disposed on the top end of the pipe. The housing includes a connector for retrieving the signal from the pressure sensitive element. The pipe further includes a wiring member disposed inside the pipe so that the wiring member connects between the pressure sensitive element and connector electrically.

In a monolithic electronic component in which a resistive element is incorporated by forming a resistor film on a terminal electrode, a plating film can be formed on the terminal electrode having the resistor film via electroplating in an efficient manner and with a uniform film thickness. In order to form the terminal electrode, the resistor film is disposed directly on the surface of the component body, and a conductive resin film having a relatively low volume resistivity is disposed over the resistor film. The conductive resin film is preferably adapted to have a specific resistance of less than about 1×10−4 Ω·m, on which a plating film having a uniform film thickness can be formed efficiently via electroplating.

The resonance of a hard disk drive using a notch filter is suppressed by detecting a resonance frequency after a far distance search is conducted, in a state in which the notch filter is disabled, and storing the detected resonance frequency as a start frequency, determining a coefficient of the notch filter to correspond to the start frequency and enabling the notch filter, detecting a resonance frequency after a far distance search is conducted, in a state in which the notch filter is enabled, and storing the detected resonance frequency as a target frequency, and changing the coefficient of the notch filter to correspond to the target frequency.

The invention discloses a damping control method in a non-electrolytic capacitance permanent-magnet synchronous-motor air conditioning drive system and relates to a method for inhibiting resonance inthe built-in permanent-magnet synchronous-motor air conditioning drive system with an aim to solve the problem about resonance generated from interaction of an input side filter and a direct-current bus capacitor of the air conditioning drive system. The damping control method includes: 1), when the permanent-magnet synchronous motor runs, processing direct-current bus voltage by using a band-passfilter and multiplying the direct-current bus voltage by a coefficient K to obtain damping current; 2), performing processing according to the obtained damping current to obtain equivalent damping power and controlling the damping current by controlling the damping power, wherein the expression of the damping power is the damping current multiplied by the direct-current bus voltage; 3), changingoutput power of an inverter to achieve the damping power, generating an extra voltage reference value to have the output power of the inverter changed, and finally, generating an extra voltage commandsignal to have resonance in the system inhibited. The damping control method is applicable to the technical field of motor control.

The invention discloses a method for restraining a voltage background harmonic wave of a grid-connected inverter. The method adopts a direct-current source, an IGBT (Insulated Gate Bipolar Transistor) intelligent power module and an LCL (Lower Control Limit) type filter, wherein the direct-current source is subjected to a single-phase inversion output through the IGBT intelligent power module; and the single-phase inversion output is accessed to a power grid after being accessed with the LCL type filter. The method disclosed by the invention is characterized by comprising the following steps of: multiplying a sampling voltage signal of the power grid with a reference current amplitude I* after carrying out PLL (Phase Locking Loop) phase locking, so as to obtain a reference current signal; carrying out closed-loop adjustment on the reference current signal and a feedback current iL2 so as to obtain a first path of signals; multiplying the sampling voltage signal of the power grid with a feed-forward function so as to obtain a second path of signals; multiplying a capacitive current signal led by a capacitive branch of the LCL type filter with a virtual resistance function so as to obtain a third path of signals; and combining the first path of the signals, the second path of the signals and the third paths of the signals and then sending the combined signals to Ginv(s) for modulation so as to generate a PWM (Pulse Width Modulation) gate pole drive signal; and triggering a switching tube of the IGBT intelligent power module to be switched on or off by the PWM gate pole drive signal. With the adoption of the method disclosed by the invention, the influence of the background harmonic wave of the power grid can be effectively removed.

The present invention provides a shake correction device which can not generate the hysteresis phenomenon and can suppress unnecessary resonance and improve endurance with respect to drop impact. In this shake correction device, the eddy current induction plate 16a of +Z side is opposite to and has a gap with the surface (14a) of the +Z side of the permanent magnet (14) which is arranged to wind around the optical axis at an interval of 90 degree in the Z direction, the eddy current induction plate 16b of radial direction is opposite to and has a space with the surface (14b) of the outside in the radial direction, and the eddy current induction plate 16c of the periphery direction is opposite to and has a gap with the surface (14c) in the periphery direction.

The invention relates to a redundant drive five degrees of freedom parallel machine tool with a large rotation angle. The redundant drive five degrees of freedom parallel machine tool with the large rotation angle includes a fixed platform, a movable platform for installing a main shaft head and a first driving branch, a second driving branch, a third driving branch and a fourth driving branch forconnecting the fixed platform and the movable platform, the structures of the first driving branch and the second driving branch are similar, and the first driving branch includes a hooke hinge, a servo driving unit, a revolute pair and a compound sphere hinge; the third driving branch includes a hooke hinge, a servo driving unit and a compound sphere hinge, the fourth driving branch includes a revolute pair, a servo driving unit, a hooke hinge and a revolute pair, and the movable platform of a machine tool and the four driving branches are hinged to form a space closed-cycle parallel mechanism; and the three-dimensional translation and the two-dimensional rotation of the space can be achieved by controlling six servo motors to drive the four branches. The redundant drive five degrees offreedom parallel machine tool with the large rotation angle has the advantages that the branch structures are simple and compact, the orientation workspace is large, the flexibility is high, the rigidity is large, and the singular configuration can be prevented, and can be used for high-speed, high-precision and efficiency machining for free-form surface in complex space.

In an ion trap mass spectrometer including an ion trap space surrounded by a ring electrode and two end cap electrodes placed opposite each other with the ring electrode between them, a method of trapping object ions of a predetermined mass-to-charge ratio in the ion trap space more assuredly and effectively. The method includes the steps of: applying an RF voltage to the ring electrode to trap the object ions; and applying an auxiliary AC voltage to the end cap electrodes, where the auxiliary voltage has a frequency spectrum with a first notch at the basic frequency of the object ions and a second notch at a a beat frequency. Then the second stage is performed where another auxiliary AC voltage of the beat frequency is applied to the end cap electrodes to expel non-object ions still remaining in the ion trap space.

The present invention relates to the lens driving device comprising the spring 90. The spring 90 comprises the holder installation parts 93a to 93d installed to the lens holder 40, the flame installation parts 94a to 94d installed to the flame 60, and the wire installation parts 92a to 92d installed to the suspension wire 16. The space 63 is formed between a first step plane 64a of the flame 60, and a part of the spring 90 positioned between the flame installation part 94a and the wire installation parts 92a to 92d; and the vibration absorbing member 70c is placed at the space 63. At the damper space between the damper table 24 and the rear plane of the flame 60, the vibration absorbing member 70a is filled. At the inner circumference plane of the flame 60, the depression part 74 is formed which is opened towards the space, and the vibration absorbing member 70b which is filled in the space is also continuously filled to the depression part 74.

The invention relates to a traction power supply network tail end voltage boosting device with a power fusing function and a method of the device. The device includes a multiple voltage reduction module and a power-fusing current-converting module; the multiple voltage reduction module is connected into two power supply arm power sources of the tail end of a traction power supply network and includes two single-phase multi-winding transformers of the same structure which are correspondingly connected into the two power supply arm power sources respectively through connection switches; the power-fusing current-converting module is used for performing energy conversion on the two power supply arm power sources and includes a plurality of current conversion sub modules; one set of voltage is connected into two input sides of each current conversion sub module through corresponding secondary windings of the two single-phase multi-winding transformers, so that energy conversion can be performed; and through controlling the switch-on of the current conversion sub modules, output voltage can be boosted, and power fusion of the two power supply arms can be performed. According to the method of the invention, the voltage of the tail end of the traction power supply network can be stabilized and boosted through controlling the power-fusing current-converting module. The device and the method of the invention have the advantages of simple structure, low cost, power fusion and train power network resonance suppression, and can boost the voltage of the tail end of the traction power supply network.

A loudspeaker comprises a diaphragm, an edge operable to support, on a frame, the diaphragm in such a manner that enables vibration thereof, and a voice coil operable to generate a driving force. The voice coil is of an approximate rectangular shape, and a length of a long axis direction of the voice coil is no less than 60% of a length of a long axis direction of the diaphragm. Positions of long sides of the voice coil to be fixed on the diaphragm are positions corresponding to nodes of a primary resonance mode in a short axis direction of the diaphragm, or in the respective vicinities thereof. Accordingly, it is possible to realize a high sound quality loudspeaker having a narrow width (elongated structure), but not easily causing resonance, thereby obtaining a flat frequency characteristic.

The present application provides a linear actuator which uses a magnetic drive mechanism to drive a movable element and which can effectively suppress resonance of the movable element even when a spring member is connected thereto. Specifically, this linear actuator (1) is provided with: a stator (2), a movable element (6), a spring member (8) connected to the movable element (6) and the stator (2), and a magnetic drive mechanism (5) which drives the movable element (6) along an axis (L). Further, between the stator (2) and the movable element (6), gel-like damper members (9) that comprise silicone gel, etc., are arranged in positions on the axis (L) and / or positions surrounding the axis (L). For example, in the stator (2), the gel-like damper members (9) may be arranged in positions along the axis (L) between the movable element (6) and a base (4) opposite the movable element (6). The gel-like damper members (9) include a first gel-like damper member (91) positioned on the axis (L), and second gel-like damper members (92) positioned so as to surround the axis (L).

In an optical deflector including a mirror, a movable frame supporting the mirror, a support body surrounding the movable frame, and a first group of piezoelectric actuators and a second group of piezoelectric actuators alternating with the first group of piezoelectric actuators, a driver combines first and second original saw-tooth waves having the same waveform into first saw-tooth waves, and applies a first drive voltage having the first saw-tooth waves to the first group of piezoelectric actuators. The driver applies a second drive voltage having second saw-tooth waves opposite in phase with the first saw-tooth waves to the second group of piezoelectric actuators.

In a clutch device 1, a second flywheel assembly 5 is axially movable within a predetermined range relative to a crankshaft 2, and a flywheel 21 has a friction surface 21a on a side remote from an engine. The damper mechanism 6 elastically couples the flywheel 21 to the crankshaft 2. The clutch disk assembly 9 has a friction facing 54 neighboring the first friction surface 21a. The clutch cover assembly 8 is attached to the flywheel 21, and biases the friction facing 54 toward the first friction surface 21a. The release device 10 applies an axial load directed toward the engine to the clutch cover assembly 8, and thereby releases the load toward the friction facing 54. The relative rotation suppressing mechanism 24 couples the second flywheel assembly 5 to the disk-like member 13 when the clutch cover assembly 8 receives the axial load directed toward the engine.