5results about How to "Large frequency adjustment range" patented technology

The present invention relates to a distributed liquid level balance type vertical damper, comprising at least two first water tanks, at least one second water tank, and a liquid level balance connecting pipe for connecting the adjacent first water tanks and the second water tanks; a pressure regulating hole is provided on the top of the first water tank, and at least one baffle is provided in the first water tank, and the baffle is fixed to the first water tank through a fixing assembly; a closed air chamber is provided on the top of the second water tank; the present invention has a simple structure, low price, easy installation, good energy consumption capacity, good automatic activation performance, and strong frequency modulation capability, and can perform distributed design of dampers according to the vibration mode and damping characteristics of the bridge structure itself, and can provide damping for multi-order vertical bending vibration modes of the bridge, effectively control the vertical vibration of the bridge structure, and improve the comfort and safety of the bridge.

The invention relates to the technical field of cable fittings, in particular to a fast-assembly frequency-adjustable damper for an optical cable, which comprises a clamping piece provided with a cable groove, one side of the clamping piece is provided with a clamping port communicated with the cable groove, and the bottom of the clamping piece is provided with a mounting block. A driving screw extending in the direction parallel to the cable groove is rotationally arranged on the mounting block, and the two ends of the driving screw are symmetrically arranged on the two sides of the mounting block. The two groups of damper assemblies are respectively arranged on two sides of the mounting block. Each vibration damper assembly comprises a vibration damper body and a driving block, and the driving block is provided with a driving nut in threaded connection with the driving screw. A first guide rod is fixedly arranged on one side of the driving screw, and the driving block is slidably connected with the first guide rod. The number of the vibration damper bodies in each vibration damper assembly is two, and the two vibration damper bodies are symmetrically arranged on the two sides of the driving block. The driving blocks on the two sides can be driven to be close to or away from each other along the first guide rods by rotating the driving screw, and the overall position adjustment of the damper assembly is achieved.

This invention discloses a dynamic calibration device for a frequency-adjustable variable cross-section gas flow meter, belonging to the field of gas flow metering technology. The device includes a variable frequency motor, a rotary valve, a fan, a rectifier, a stabilizing section, a contraction section, a development section, and a testing section connected in sequence. The rotary valve consists of a stator and a rotor; the rotor rotation causes the flow cross-sectional area to change sinusoidally, generating a standard sinusoidal flow signal. The variable frequency motor is used to adjust the rotor speed, achieving precise control of the signal frequency. The fan provides suction power. The rectifier, stabilizing, contraction, and development sections are used to ensure the airflow reaches a fully developed laminar flow state. The testing section measures the pressure gradient using a dynamic pressure sensor. This invention also provides a method for obtaining a standard volumetric flow signal by solving the analytical solution of the Navier-Stokes equations based on the pressure gradient. This device solves the problems of difficulty in controlling the generation of dynamic flow signals and the difficulty in directly tracing the source of standard flow, achieving high-precision calibration of the dynamic characteristics of the gas flow meter.

The invention belongs to the field of oscillators, particularly relates to a differential cross-coupling voltage-controlled oscillator of a CLASS-D structure, and aims to solve the problem that the advantages of low power consumption, extremely low noise, wide frequency regulation range and complete output waveform cannot be achieved in the prior art. According to the invention, a resonance stage module and a filtering stage module are connected through blocking capacitors Cm1 and Cm2; the resonance level module is based on a CLASS-D structure and is used for generating an oscillation signal with extremely low noise, and the frequency of the oscillation signal is adjusted through frequency band selection and a variable capacitance diode; and the filtering stage module is used for carrying out band-pass filtering and swing adjustment on the signal generated by the resonance stage module, realizing distortion waveform recovery and outputting a pair of differential sine wave signals. The circuit has the advantages of extremely low noise, wide frequency adjustment range, good signal integrity, low power consumption and the like.

The application provides a four-mode voltage-controlled oscillator, comprising four kernel units, one kernel unit is composed of two cores, and the whole is an eight-core structure, four different modes are generated to achieve a double-octave tuning range. The application benefits from a completely magnetically induced mode, which does not use additional capacitors, and finally realizes a high figure of merit (FoM) in the ultra-high frequency range, enhancing the frequency range of the PLL. The application is based on an eight-core four-mode wide tuning VCO structure of 8-shaped inductors, which skillfully uses the magnetic field coupling and inductance evanescent scheme to tightly couple the eight cores together, achieving super-multi-core and super-wide tuning range without losing additional area. It has a wider frequency adjustment range, smaller area and lower power consumption.