77results about How to "Fast frequency response" patented technology

The invention provides a wind tunnel experiment strut vibration suppression system and method based on a piezoelectric technology. The system comprises a laser displacement sensor, a data collector, a control calculation module, a closed loop amplification module and a piezoelectric actuator. The method comprises the steps that: the laser displacement sensor collects the normal vibration displacement of a controlled strut; a normal vibration displacement signal is converted into a normal vibration displacement digital amount through the data collector; the normal vibration displacement digital amount is used as feedback control and is sent to the control calculation module; an actuating control voltage signal is obtained through performing PID control in the control calculation module; the actuating control voltage signal is amplified to drive the piezoelectric actuator to generate an actuating force to increase structure damping of the system, so that the vibration of the strut in the wind tunnel experiment is suppressed, the strut vibration caused by the impact of a wind tunnel starting impacting load to the model is reduced, the wind tunnel test device and the tested model structure are protected and the signal to noise ratio of the dynamic wind tunnel experiment data is increased.

A water-repellent earphone is formed of a main body and a water-repellent breathable member. The main body includes a receiving space for accommodating a speaker. The speaker partitions the receiving space to make a rear chamber. The main body includes a drainage tunnel communication with a first opening and a second opening, both of which are located on an external surface of the main body. The main body further includes a venthole communicating with the drainage tunnel and the rear chamber. The water-repellent breathable member is formed and located at the venthole. In light of the structure mentioned above, the drainage tunnel can help the earphone quickly expel the moisture to prevent the moisture from damage to the speaker and to boost the frequency response and acoustic performance within the low-frequency range.

The invention discloses an acoustic surface wave pressure sensor and an acoustic surface wave temperature sensor which can improve pressure-measuring sensitivity or a temperature frequency response speed and comprise a top cover and a base. The top cover and the base are sealed and mounted together, and metal electrodes penetrate through the base which is provided with a pressure conduction through hole; a fluid septum is sealed and fixed on the inner surface of the base to cover the pressure conduction through hole; a closing cavity is formed among the base, the top cover and the fluid septum; both ends of a substrate are fixed on the fluid septum, and the substrate bridges the pressure conduction through hole; an acoustic surface wave pressure sensing resonator and a datum resonator which are arranged on the substrate and the substrate are mutually parallel along the length direction; an acoustic surface wave temperature sensing resonator forms a horizontal included angle with the datum resonator; the acoustic surface wave pressure sensing resonator rightly faces to the central part of the pressure conduction through hole; the acoustic surface wave temperature sensing resonator, the acoustic surface wave pressure sensing resonator and the datum resonator are respectively connected with corresponding bonding pads; the metal electrodes are correspondingly connected with the two bonding pads; and a frontal projected area of a pressure sensitive area on the substrate is smaller than a cross section area of the pressure conduction through hole.

The invention discloses an automatic sorting platform used for weighing detection of materials. The automatic sorting platform comprises a frame, a storage groove, first springs, a supporting plate, asecond spring, a supporting block, a first travel switch, a third spring, a second supporting block, a second travel switch, an electric push rod, a timer, a motor, a rotary shaft and a rotary arm. The automatic sorting platform used for weighing detection of materials is ingenious in structure, powerful in function, easy to operate and capable of saving time and labor. First, materials with different weights are separated first through the design of a weight detection mechanism; second, the materials with different weights are transferred in a classified mode under the cooperative effect ofa rotating mechanism; and finally, by adoption of the automatic sorting platform, the problems of large time and labor consumption and low efficiency caused by manual sorting of the materials with different weights by workers are effectively solved, and the workload of the workers is reduced.

An inclined trough type 2D electro-hydraulic high-speed switching valve with a variable transmission ratio transmission mechanism comprises a valve body, the transmission mechanism for driving the valve body to be opened and a zero position keeping mechanism for driving the valve body to be closed. An oil inlet cavity communicates with an oil inlet in the valve body and communicates with a valve element through an oil passing hole in the valve element. High-pressure holes communicate with the valve element, and a sensitive cavity communicates with the oil inlet cavity through the oil passing hole, the high-pressure holes and inclined troughs. The sensitive cavity communicates with an oil outlet cavity through low-pressure troughs and the inclined troughs, and the oil outlet cavity communicates with an oil outlet in the valve body. The length, in the axial direction, of a second circular bead is larger than the diameter of the oil outlet, and the oil outlet is located in the motion track of the second circular bead. The lower half part of an upper lifting lever extends into a U-shaped fork of a lower shifting fork, a rotating shaft of rotating equipment is fixedly connected with the upper lifting lever, and a reset spring of the upper lifting lever enables the upper lifting lever to abut against the interior of the lower shifting fork in an inclined manner. The zero position keeping mechanism for forcing the valve body to be kept at the zero position is arranged on the right side of the valve body.

The invention discloses an automatic storage battery charging-discharging and capacity detection device which comprises an ARM control unit, a storage battery charging unit and a BUCK step-down circuit drive and constant current output unit. The output end of the ARM control unit is connected with the storage battery charging unit and the BUCK step-down circuit drive and constant current output unit; the ARM control unit is formed by a signal acquisition circuit, an ARM minimum system circuit, a communication control circuit and an upper computer, and the signal acquisition circuit, the ARM minimum system circuit, the communication control circuit and the upper computer are connected in sequence; the storage battery charging unit comprises a charger, a storage battery and a corresponding charging control circuit, the positive electrode of the charger is connected with the power supply positive electrode of the ARM control unit, and power supply to the ARM control unit is achieved; the BUCK step-down circuit drive and constant current output unit comprises an MOS drive circuit, a BUCK step-down circuit and a discharging load resistor. The automatic storage battery charging-discharging and capacity detection device is simple in structure and high in anti-jamming capability and has application and popularization value, and the storage battery is automatically charged and discharged without manual operation.

A liquid crystal display comprises a display panel that includes at least one pixel transistor, at least one pixel electrode in electrical communication with the pixel transistor, at least one common electrode, and a liquid crystal material between the pixel electrode and the common electrode. The pixel transistor includes a thin film layer of essentially single crystal silicon that has a thickness in a range of between about 100 nm and about 200 nm. The pixel electrode has a thickness in a range of between about 5 nm and about 20 nm. The common electrode has a thickness of between about 50 nm and about 200 nm.

The invention discloses a wind speed sensor and a detection method for detecting cotton heterosexual fibers. A central bearing is connected to a wind direction cup device through sliding balls, and several wind direction cups are horizontally distributed on the outside of the wind direction cup device along the circumferential direction; the middle section of the center bearing is coaxial Fixed gear, the top of each tooth of the gear is fixedly pasted with a magnetic steel sheet; there is an inductive switch element on the front end of the Hall sensor, the inductive switch element is located near the magnetic steel sheet and the two are on the same level, and the Hall sensor is connected internally The photoelectric coupler and the wind cup rotate with the wind to drive the central bearing and the gear to rotate synchronously, and the Hall effect is generated between the magnetic steel sheet and the Hall sensor switch; then the frequency of the pulse signal is measured by the multi-cycle synchronization method through the single-chip microcomputer, The pulse signal is proportional to the signal of the speed of the wind cup, so that the output signal can be measured with equal precision in the whole frequency range, the measurement error is reduced, and the measurement accuracy of the frequency of the pulse signal is improved.

The invention provides a wind power frequency modulation control method suitable for a high wind power penetration level, and relates to the field of wind power generation grid connection, and the method comprises the following steps: monitoring the frequency of a power grid in real time, calculating the instantaneous frequency of the power grid, and when the frequency deviation of the power grid exceeds a set dead zone range due to the disturbance of a power system, measuring the rotating speed of a fan, and when the rotating speed omega r of a fan rotor is larger than the allowable minimum rotating speed omega min, starting a virtual inertia control module of the doubly-fed wind turbine generator, wherein the fan actively participates in frequency modulation; calculating the active increment of the wind turbine generator; calculating the equivalent active power increment of the time domain; calculating an active reference value of the fan; and after the time delta t, gently switching the active power output of the fan to the maximum power tracking output power, so the rotating speed gradually recovers to the initial state. A virtual inertia control link is additionally added to a wind turbine generator rotor side converter controller, when the power grid frequency exceeds the limit due to disturbance, the virtual inertia control link participates in frequency modulation of a power system by use of the rapid throughput of kinetic power of the fan rotor, the frequency modulation response is faster, and the effect is better.

The invention discloses a pus drainage device with a sampling function for patients with burns, which comprises a drain tube, a housing, an upper cover, a support block, a guide tube, a filter net, aholding channel, a limiting channel, a slider, a spring, a flow hole, a receiving hole, and a floater. The pus drainage device is ingenious in structure, good in functionality, simple to operate and low in time and manpower consumption; a sampling mechanism enables medical personnel to conveniently carry out sampling detection on drained liquid during drainage therapy of a patient; the problem iseffectively avoided that a traditional sampling method is inconvenient to perform and high in time and manpower consumption; in addition, a drainage alarm mechanism helps effectively prevent untimelyemptying of the drained liquid in the housing from affecting the drainage therapy of the patient; operation is finally simplified for medical personnel, treatment and healing are benefited for the patient. The pus drainage device is suitable for clinical popularization and application.

The invention discloses an alternating current detection circuit and an automatic power-off circuit with zero power-off power consumption. The alternating current detection circuit comprises resistors R1 and R2, a capacitor C1, a filter element C2, diodes D1 and D2, and a photoelectric tube U1, wherein a positive end of the diode D1 is connected with a negative end of the diode D2, and a connecting end is an end point X; the negative end of the diode D1 is connected with the positive end of the diode D2, and the connecting end is an end point Y; two ends of the resistor R1 are connected with the end point X and the end point Y; and the alternating current detection circuit also comprises a diode D3 or a triode P1. The automatic power-off circuit with the zero power-off power consumption is provided with the alternating current detection circuit which serves as a current detection device. By adoption of the alternating current detection circuit and the automatic power-off circuit, a current can be quite conveniently detected, a circuit structure is easy to minimize, and after electric equipment is closed, a socket can be totally disconnected from an external power supply.

The invention discloses an electrically-controlled hydraulic steering control device, which comprises a frequency-voltage conversion chip (1), a voltage comparison module (2), a logical operation module (3), an electromagnetic valve drive module (4), a power module (5), an undervoltage protection module (6) and an overcurrent protection module (7). The control device is applicable to double-electromagnetic-valve bypass flow type electrically-controlled hydraulic steering systems. The control device controls opening and closing of the two electromagnetic valves of the double-electromagnetic-valve device jointly and adjusts the bypass flow to change flow of oil entering a steering gear, so that assisted adjustment can be realized. The electrically-controlled hydraulic steering control device is low in cost, quick in response, low in heat productivity and capable of effectively guaranteeing steering portability of an automobile at low speed and stability of the automobile at high speed, and enables a driver to have a good operating feeling.

The invention discloses a large-load and high-frequency in-situ tension and fatigue tester based on X-ray imaging. An imaging displacement stage can be rotatably mounted on a test platform; a base isfixed on the imaging displacement stage, a rack is arranged on the base, a servo hydraulic cylinder is arranged on the rack, a lower clamp is rotatably connected to an upper end of a piston rod of thehydraulic cylinder, a support seat platform is fixed on four uprights of the rack; a support tube is located at an upper side of the support seat platform, a transparent cover is embedded between thesupport seat platform and the support tube; an upper clamp is fixed on the support tube; an electrolyte servo valve is connected with an upper oil chamber and a lower oil chamber of the hydraulic cylinder; a load sensor, the electrolyte servo valve and a X-ray detector are orderly connected with a data collection and control unit and a data processing unit. The tester disclosed by the invention has the features of being large in load, high in frequency, small in volume, and high in precision.

The invention provides a constant-tension wire conveying device and a tension measurement method. The constant-tension wire conveying device comprises a wire storage cylinder, an electrode wire, an upper wire discharge wheel, a lower wire discharge wheel, a wire tightening mechanism, an upper guide wheel and a lower guide wheel. The constant-tension wire conveying device is characterized by further comprising an upper tension measurement wheel, an upper tension measurement sensor, a lower tension measurement wheel, a lower tension measurement sensor and a tension control circuit; the wire tightening mechanism comprises a connecting plate, a connecting plate driving device, an upper wire tightening wheel, an upper shock absorber, a lower wire tightening wheel and a lower shock absorber; onan electrode wire conveying path, the upper tension measurement wheel is located between the upper wire tightening wheel and the upper guide wheel, and the lower tension measurement wheel is located between the lower wire tightening wheel and the lower guide wheel; in the moving process of the connecting plate, the wrap angle where the electrode wire makes contact with the upper tension measurement wheel and the wrap angle where the electrode wire makes contact with the lower tension measurement wheel remain unchanged. Tension of the electrode wire at the upper end of an electric discharge machining area is transferred to the upper tension measurement sensor through the upper tension measurement wheel; the tension of the electrode wire at the lower end of the electric discharge machining area is transferred to the lower tension measurement sensor through the lower tension measurement wheel. The two parts of tension are added to serve as the basis for conducting constant-tension closed-loop control over the electrode wire.

The invention discloses an aircraft disturbance control method, system and device. The method comprises the steps of: acquiring the current acceleration value of an aircraft; comparing the current acceleration value with an acceleration given value, and judging whether a comparison result meets a preset comparison condition or not; and under the condition that the comparison result does not meet the preset comparison condition, controlling the aircraft. According to the control method, the current acceleration value of the aircraft is acquired, and the aircraft is controlled under the condition that the current acceleration value is different from the acceleration given value. As the acceleration is direct measurement of the force, the control method has the characteristics of short period and high frequency response speed, and the response speed of the system is greatly increased.

The present invention relates to one sensor converting elastic micro variation of rigid body into electrical parameter variation. The sensor includes metal film type mechanical resonant follower, electronic resonant frequency selector, resonant driver and detection and shaping circuit. After the sensor is installed in the sampled part of detected metal rigid body, the detected metal rigid body is applied with some external force to produce micro elastic deformation and the elastic deformation is fed via the mechanical resonant follower, electronic resonant frequency selector and resonant driver to the detection and shaping circuit, so that the variation is measured. The sensor has simple structure and high sensitivity.

The invention relates to a container cleaning-drying and filling-sealing interlocking machine set control system, which comprises a detection element, a control element, an actuator element and an operating element, wherein the detection element is a non-electricity measurement sensor; the control element is a programmable logic controller (PLC); the operating element is a touch screen; the programmable logic controller (PLC) comprises a central processing unit (CPU) and an extension unit; the extension unit comprises an output extension unit and a temperature control unit; the temperature control unit is connected with the CPU; the CPU of the programmable logic controller (PLC) is connected with the non-electricity measurement sensor, the actuator element and the touch screen respectively; and the temperature control unit is sequentially connected with the actuator element and the non-electricity measurement sensor to form a closed loop structure. The scheme ensures low production cost, and meets the requirements of electronic tags and electronic records of good manufacturing practice (GMP) as well as the requirements on energy saving, emission reduction and high efficiency.

The invention provides a leveling control system structure capable of realizing switching of multiple flow ranges. The leveling control system structure is used for leveling a pressure output end sliding block of a press, and a leveling unit powered by a constant-pressure oil source is arranged below each corner end of the sliding block; each leveling unit is in contact with the corner end of thesliding block through a leveling cylinder provided with a displacement sensor; a rod cavity of each leveling cylinder is connected with a first pressure sensor, and a rodless cavity of each leveling cylinder is connected with a second pressure sensor; and an oil outlet path of each leveling cylinder is connected with a control valve bank so as to switch the multiple flow ranges to meet different flow requirements of the system under multiple working conditions, and the levelness of the sliding block during falling is guaranteed by improving the position synchronous control precision of the leveling cylinders of the leveling units. According to the leveling control system structure, the flow requirements under various working conditions can be accurately matched, so that the flow control accuracy of the leveling system is improved.

The invention discloses a novel low-voltage high-frequency band inverter circuit. A hysteresis comparison input negative electrode is connected with a reference input R2 and a feedback input R3, a positive electrode is in integral association with a matching resistor R1 and a capacitor C1, and the output of a comparator directly drives a load resistor R4. The operational amplifier working power supply V + is connected to the emitting electrode of a triode D3, and the base electrode of the operational amplifier working power supply V + is connected with the reference voltage formed by a resistor, a voltage-regulator tube and a capacitor. A collector electrode of the operational amplifier power supply generation triode D3 is connected in series with a current-limiting resistor R9 and a driving resistor R7, and the two resistors are connected to a grid electrode of a power tube D2 through the current-limiting resistor after voltage division. A PNP triode, a current-limiting resistor R10 and a sampling resistor R11 form a power tube protection loop which is used for the real-time protection of the power tube D2. According to the invention, a brand-new inversion control idea is used, through the reasonable parameter design, hundreds of volt-amperes of power output can be provided for the loop, and the novel low-voltage high-frequency band inverter circuit has the advantages of fastfrequency response speed, simple structure, convenient debugging and the like.