175results about How to "Eliminate resonance" patented technology

A control system for a resilient support mechanism such as a suspension mechanism of a wheeled vehicle including a damper disposed between an unsprung mass member and a sprung mass member of the vehicle, wherein a damping coefficient of the damper is divided into a linear portion and a nonlinear portion, and wherein the nonlinear portion of the damping coefficient is defined as a control input u and applied with a frequency weight Wu(s), while a vertical velocity of the sprung mass member, a relative velocity of the sprung mass member to the unsprung mass member and a vertical acceleration of the sprung mass member are defined as an evaluation output zp and applied with a frequency weight Ws(s). In the control system, a nonlinear Hinfin control theory is applied to a generalized plant to obtain a positive definite symmetric solution P and to calculate a target damping force based on the positive definite symmetric solution P and a state amount such as the vertical velocity of the sprung mass member, a relative displacement of the sprung mass member to the unsprung mass member or the like.

The invention relates to a movable micro turbine jet engine test bed, which consists of a test bed rack and a control cabinet. An engine to be tested and various measurement sensors are installed on the test bed rack. The test bed rack is connected with the control cabinet through conducting wires. Various meters and a computer are installed in the control cabinet. The control cabinet is used for receiving test data and controlling the running state of the engine. The test bed rack consists of a flow measuring pipe, a weighing sensor, a weighing sensor support, sliding rail shafts, sliding rail shaft supports, an oil tank, moving wheels, fixed wheels, lead screw supports, a main body support steel frame, a fixing plate, a tail jet pipe support, a tail jet pipe, temperature sensors, a protection cover, a sliding plate, an engine supporting base, a pressure measuring joint, the engine to be tested, a front inner flow guide cover, sliding plate connecting blocks, a flow meter, a micro differential pressure transmitter, an electronic control unit (ECU) and pressure transmitters. The control cabinet consists of a cabinet body, various meters, the computer, four corner wheels and an ECU control assembly. The movable micro turbine jet engine test bed is flexible and convenient, and provides an equipment support for the accurate determination of the performance of the micro turbine jet engine.

Embodiments provide a lens moving apparatus including a housing supporting a driving magnet and having an opening, a bobbin provided at an outer circumferential surface thereof with a coil located inside the driving magnet, the bobbin being moved in a first direction parallel to an optical axis within the housing via electromagnetic interaction between the driving magnet and the coil, and a damper located between the housing and the bobbin.

The invention relates to a spinning process of bamboo-like flat filaments produced by a semi-continuous high-speed spinning machine and belongs to the technical field of spinning of semi-continuous spinning machines. The spinning process comprises glue supply, filament strip forming, spinning and winding. The spinning process is characterized in that the glue supply is achieved through a glue supply device which comprises a metering pump, a glue supply tube and a filter; the metering pump is connected with a frequency converter which is used for controlling the amount of the glue supply of the metering pump; the frequency converter controls the metering pump to perform intermittent glue supply; the spinning is achieved through a spinning device which comprises at least one spinning roller which is horizontally arranged relative to an operating surface of a spinning surface; and filament strips surround the spinning roller to achieve drafting, solidification and deacidification in the spinning processes under the rotation of the spinning roller. The spinning process of the bamboo-like flat filaments produced by the semi-continuous high-speed spinning machine has the advantages of solving the problems that the filament strips of the semi-continuous spinning machines are inadequate in response, so that the spinning speed cannot be improved and the production efficiency and product quality cannot be integrated, enabling the arrangement direction of the spinning roller to be changed to enable the spinning speed of the spinning machine to be improved and enabling the high quality bamboo-like flat filaments to be spun out.

An automobile test bench comprises a portal frame, at least one group of actuator, a clamp mechanism and a supporting mechanism which supports the structure of the whole test bench, the clamp mechanism is respectively connected with the actuator and the supporting mechanism and used for fixing a test article, the actuator is movably installed on the portal frame and comprises a sliding mechanism, an actuating cylinder and spherical hinges, wherein the sliding mechanism is installed on a beam of the portal frame, the spherical hinges are arranged at the upper and lower ends of the actuating cylinder, the sliding mechanism is connected with the actuating cylinder through the upper end spherical hinge, and the clamp mechanism is connected with the actuating cylinder through the lower end spherical hinge. The actuator is connected through the gapless spherical hinges, the problem of resonance vibration caused by fit clearance is eliminated, moreover, the actuating cylinder is capable of moving, convenience of the installation of the test article is increased, and working efficiency is improved.

The invention discloses an ultrafine pulverizer. A gear ring of a pulverizing mechanism of the ultrafine pulverizer is formed by connecting and splicing a plurality of identical gear ring arc sections end to end; inclined teeth inclining towards the axial direction of the gear ring are arranged in the arc sections of the gear ring; alloy strips are arranged on the inclined teeth by oxygen welding; a plurality of grooves are formed in the alloy strips; a dentoid structure is arranged on one side, facing to the gear ring, of each hammerhead; the dentoid structures are inclined teeth inclining towards the normal direction of a wearproof tray; and the inclination directions of the inclined teeth on the hammerheads are opposite to those of the inclined teeth on the gear ring. According to the ultrafine pulverizer, with the adoption of the inclined tooth structures of the gear ring and the hammerheads, the impact of a high-speed air flow on materials in the pulverizer is improved, and the collision and the friction among materials are increased, so that the pulverizing efficiency and effect are improved effectively; the yield by the pulverizer is increased; the abrasion performances of the hammerheads and the gear ring are improved with the adoption of the alloy materials; the service life of the hammerheads and the gear ring is further prolonged; and the maintenance cost is reduced.

The invention discloses a digital automatic harmonic elimination device which comprises a residual voltage input unit, a harmonic elimination unit, a singlechip and a display setting unit. Data collected by the residual voltage input unit collects is converted by an A/D and sent to the singlechip which calculates and obtains data larger than a fixed value given by the display setting unit and triggers a bidirectional thyristor to switch on by controlling an optocoupler; the harmonic elimination unit is switched in a PT open triangle, a voltage collecting unit for collecting the three-phase voltages of a bus is also switched in the A/D connected with a data interface of the singlechip which calculates the data collected by the voltage collecting unit, obtains a residual voltage by and compares the residual voltage with a residual voltage obtained by the open triangle; single-phase grounding occurs if a difference value is smaller than the setting value, and power frequency resonance occurs if the difference value is larger than or equal to the setting value. The invention can accurately distinguish the defaults, such as the power frequency resonance, the single-phase grounding, and the like, accurately eliminates the system resonance in time and has the functions of over-voltage protection, low-voltage protection and PT break judgment.

The invention discloses an arc and resonance elimination comprehensive device for a power grid, which solves the problems that the conventional arc elimination cabinet cannot determine a circuit in which arc light is generated and an arc suppression coil cannot limit intermittent arc overvoltage and cannot eliminate high-frequency intermittent arc grounding. The device comprises a high energy voltage limiter, a vacuum contactor, a current limiting fuse, a controller and a voltage transformer; and an operation module of the controller performs operation processing on information sent by a main measurement module, a main control module and a line selection module, and the controller sends an instruction to control the vacuum contactor to correctly act so as to eliminate the arc and the resonance and select a line. The arc and resonance elimination comprehensive device can completely eliminate arc grounding and the resonance of a power grid system, and reliably realizes segment protection for the power grid system and equipment; and a defect that the conventional arc and resonance elimination cabinets use and all act in the same potential is overcome.

A sounding body unit has a sounding body, a mesh section, and a housing mounting the sounding body with the mesh section. The housing has a projection, and the projection is pressed against the mesh section in order to prevent the mesh section from resonating with sounds radiated from the sounding body.

The invention relates to a multi-frequency antenna system and a method for controlling inter-frequency interference in the multi-frequency antenna system. The multi-frequency antenna system comprises at least one first radiating element and at least one second radiating element, and is characterized in that the operating frequency band of the first radiating element is higher than the operating frequency band of the second radiating element; each of the first radiating element comprises a grounding structure, a balun and at least two radiating arms, and one end of the balun is electrically connected with the at least two radiating arms; the balun comprises at least one conduction structure; and the balun is used for acquiring differential mode signals and inputting the differential mode signals into the grounding structure through the at least one conduction structure, and the differential signals are obtained in a way that the balun senses signals from the second radiating element in a differential mode manner. Inter-frequency interference brought about by differential mode resonance between radiating elements with different frequencies can be reduced through adopting the scheme.

The invention provides a production process of soundproof cotton. The production process comprises a cotton combing process, a melt-blowing net forming process, a covering process, an embossing and cutting process and a punching process. According to the production process of the soundproof cotton, polypropylene is melt-blown on a hollow polyester cotton roll to improve the strength of the soundproof cotton and ensure that the soundproof cotton can not be damaged easily during mounting and use, can not be aged easily and is good in weather resistance and long in service life. In the covering process of the production process of the soundproof cotton, a small amount of glue is uniformly sprayed on the surface of the hollow polyester cotton roll at first, then a non-woven fabric covering process is carried out, and a glue is added between the non-woven fabric and the hollow polyester cotton roll to ensure that the produced soundproof cotton is more stable and durable in structure, and the service life of the soundproof cotton is effectively prolonged.

The invention relates to a unidirectional pulley, in particular to the unidirectional pulley for an AC generator, which is arranged on a transmission shaft of the AC generator and allows the speed of the pulley to fluctuate relative to the transmission shaft of the AC generator owing to speed fluctuation of an engine. The unidirectional pulley consists of the pulley, a core shaft, a torque spring, a friction spring, a thrust washer and a retainer, wherein, the retainer is made of plastics and composed of a roughly annular end part and a tubular spacer bush part which is provided with an axial elongated slot which is equally distributed circumferentially and used for eliminating resonance generated while the pulley runs; and the friction spring is wound on the spacer bush part of the retainer, and the torque spring is sheathed on the core shaft and positioned in the spacer bush part of the retainer. The unidirectional pulley can eliminate the resonance generated while the AC generator runs and prolong service life of the unidirectional pulley for the AC generator.

The invention discloses an oil supporting positioning device for machining of a thin-walled spherical workpiece. The oil supporting positioning device comprises a supporting pedestal. The top of the supporting pedestal is provided with a table board. The oil supporting positioning device is characterized in that the table board is provided with a semispherical groove allowing the thin-walled spherical workpiece to be embedded in; an oil filling nozzle is arranged on the outer wall of the supporting pedestal; oil filling holes communicating with the oil filling nozzle are formed in the inner wall of the semispherical groove; the oil supporting positioning device further comprises an annular pressing plate used for fixing the thin-walled spherical workpiece; a circle of positioning flange isarranged on the periphery of the upper portion of the supporting pedestal integrally; the positioning flange is provided with a plurality of positioning holes used for arranging bolts in a penetrating mode so that the annular pressing plate can be locked to the table board; the inner edge of the annular pressing plate inwards extends our of the inner wall of the semispherical groove; and after the thin-walled spherical workpiece is arranged in the semispherical groove, an oil filling cavity for oil filling is formed among the annular pressing plate, the outer wall of the thin-walled sphericalworkpiece and the inner wall of the semispherical groove. Through the device, the thin-walled spherical workpiece can be better supported, resonance is avoided, in addition, pressure does not need tobe applied through an air compressor or an oil press, and the workpiece is prevented from being deformed.

The invention discloses a processing technology of a speaker frame with precisely punched riveting holes and mounting holes. The processing technology comprises a series of steps of cutting, blanking, punching location holes, drawing, punching and trimming, punching the riveting holes, punching shock absorption slots, flanging and screeding, punching ear patterns, punching ear holes, punching single patterns, and punching the mounting holes. The invention aims to provide the processing technology of the speaker frame with the precisely punched riveting holes and mounting holes.

The invention discloses an automatic tracking small-current line selection device and a line selection method. The device is characterized in that a neutral point is arranged in a system with a small-current grounding mode, a controllable impedance part capable of achieving automatic tracking adjustment is arranged between the neutral point and the ground, and a maximum value of the controllable impedance part is set according to the rated voltage of the system; the controllable impedance part is tracked and adjusted according to the system-to-ground voltage or the current of the controllableimpedance part. According to the device and the method, the zero sequence current of a fault line is maximized, the judgment precision of the line selection current is high, the fault line is accurately judged, and line selection is not affected by an arc suppression coil; moreover, the device can be applied to judgement of the fault line when a small-resistance grounding system is grounded with high resistance, and a protection dead zone of the neutral point small-resistance grounding system is removed.

The invention provides an air bag type intermediate supporting device for a transmission shaft of a commercial vehicle, an assembling method and a using method. The air bag type intermediate supporting device comprises a rim type bearing seat. The rim type bearing seat is provided with an inner ring and an outer ring which are connected with each other; a bearing is pressed on the periphery of theinner ring; a clamping groove is formed between the outer edge of the inner ring and the outer ring; an elastic check ring is installed in the clamping groove and used for axially fixing the bearing;an annular air bag is arranged outside the outer ring; the inner side face of the annular air bag abuts against the outer ring face, and the outer side face of the annular air bag is connected with an annular combined support; and the annular combined bracket is connected with the frame. The radial rigidity of the supporting assembly is adjusted by adjusting the air pressure of the air bag, so the inherent frequency of the supporting assembly is adjusted, the resonance frequency is avoided or disturbed, and the driving comfort of the whole vehicle is improved. Meanwhile, the problem of heat dissipation of vulcanized rubber supporting is effectively solved, and the service life of the bearing is prolonged. The device is simple in structure, simple and convenient in assembly process and reliable in performance.

The invention discloses a vertical shaft blower or a wind driven generator. The vertical shaft blower or the wind driven generator is characterized in that a main shaft or a transmission shaft is movably connected with a wind wheel to successfully solve the longstanding problem influencing the further development of the vertical shaft wind driven generator that resonance is easily caused by the main shaft. In the invention, through adopting a vibration reduction sleeve, the longstanding problem influencing the further development of the vertical shaft wind driven generator that the output power fluctuates caused by different acting moments at different corners can be successfully solved.