44results about How to "Guaranteed amplitude" patented technology

The invention relates to the field of circuit design, and discloses a novel crystal oscillator circuit. A principal oscillation metal-oxide-silicon (MOS) tube circuit is imaged, bias of a principle oscillation tube is indirectly controlled by controlling direct-current bias of an imaging tube, so that a direct-current level of a sinusoidal signal outputted by the crystal oscillator is biased to a preset value, control over the direct-current level of the output signal is realized, Miller compensation can be used for compensating the stability of a negative feedback control loop, and the stability of the system is guaranteed on the premise that not a very large chip area is occupied. An output signal of a peak detection circuit is compared with a second fixed level by a second operational amplifier so as to dynamically adjust a value of a bias current and to ensure that the output signal is maintained at preset amplitude.

The invention relates to the technical field of groove profile rolling, in particular to an ultrasonic and pulse current mixing auxiliary wedge-shaped cavity profile rolling line and a rolling process. The ultrasonic and pulse current mixing auxiliary wedge-shaped cavity profile rolling line is characterized in that a left horizontal alignment roller, a pre-rolling roller, a left ultrasonic vibration roller, a left electric brush, a roller set, a right electric brush, a right ultrasonic vibration roller, a right height alignment roller and a right horizontal alignment carrier roller are sequentially arranged along the rolling line, the left horizontal alignment roller and a right horizontal alignment roller are composed of a left roller and a right roller which are horizontally arranged, the pre-rolling roller and the right height alignment roller are composed of an upper roller and a lower roller which are vertically arranged, the left ultrasonic vibration roller and a right ultrasonic vibration roller are composed of an upper roller and a lower roller which are vertically arranged, and the roller set is composed of an upper roller and a lower roller which are vertical arranged; the ultrasonic vibration module is connected with the left ultrasonic vibration roller and the right ultrasonic vibration roller, and drives the left ultrasonic vibration roller and the right ultrasonic vibration roller to vibrate ultrasonically; and the left electric brush and the right electric brush are connected with a pulse current source. The rolling difficulty of a wedge-shaped cavity profile is reduced, the rolling efficiency is improved, and the size precision and the surface finish of the wedge-shaped cavity profile are improved.

The invention relates to the technical field of wedge-shaped cavity sectional material rolling, in particular to an ultrasonic wave and induced current mixed auxiliary wedge-shaped cavity sectional material rolling line and a rolling process. A left horizontal calibration roller, a pre-rolling roller, a left ultrasonic vibration roller, a heating coil, an upper roller, a lower flat roller, a rightultrasonic vibration roller, a right height calibration roller and a right horizontal calibration carrier roller are sequentially arranged along the rolling line, the left horizontal calibration roller and the right horizontal calibration roller are composed of a left roller and a right roller which are arranged in the horizontal direction, the right height calibration roller is composed of the upper roller and a lower roller which are arranged in the vertical direction, the left ultrasonic vibration roller and the right ultrasonic vibration roller are composed of the upper roller and the lower roller which are arranged in the vertical direction, the upper roller and the lower flat roller are arranged up and down in the vertical direction, an ultrasonic vibration module is connected withthe left ultrasonic vibration roller and the right ultrasonic vibration roller and drives the left ultrasonic vibration roller and the right ultrasonic vibration roller to vibrate ultrasonically, andthe heating coil is connected with an induction current source. According to the ultrasonic wave and induced current mixed auxiliary wedge-shaped cavity sectional material rolling line and the rollingprocess, the processing forming performance is improved, the processing forming difficulty is reduced, the sectional material size precision and smoothness are improved, and the processing energy consumption is reduced.

The invention discloses an intelligent slipper low-temperature distance measurement device and method. The device comprises a distance detection module, a temperature module, a power management module, a battery, a main control module, and a wireless transmission module. The distance detection module, the wireless transmission module and the temperature module are respectively connected with the main control module, and the main control module is used for the operation coordination of a whole system. The method employs four types of methods to improve the low-temperature ultrasonic ranging precision according to temperature difference, and comprises the steps: correcting a sound speed through temperature; adjusting a driving voltage of an ultrasonic probe; dynamically adjusting the number of transmitted pulses according to the temperature, and adjusting the threshold voltage of a receiving end. Through the adjustment of software and hardware circuits, the device and method improve the distance measurement precision of an intelligent slipper under low temperature, especially in a northern cold region, and plays an important role in preventing a train from escaping and guaranteeing the safety.

The invention discloses a signal calibration circuit for an industrial building fire fighting system. The signal calibration circuit for the industrial building fire fighting system comprises a frequency acquisition circuit, a mean push-pull circuit and a filtering emission circuit; the frequency acquisition circuit acquires a signal frequency of an input end in an analog signal transmission channel in a signal transmission module of the industrial building fire fighting system; a first path of the mean push-pull circuit applies an operational amplifier AR1 to follow up a signal, and a secondpath of the mean push-pull circuit applies an operational amplifier AR4 and a triode Q3 as well as a capacitor C2 to form a noise reduction circuit to reduce a signal-to-noise ratio; then an operational amplifier AR2 is applied to carry out addition processing on two paths of signals; an output signal of the operational amplifier AR2 is input into a mean circuit consisting of an operational amplifier AR3 and a diode D2 as well as a diode D3; the filtering emission circuit applies an inductor L2 and a capacitor C4 as well as a capacitor C5 to form a filtering circuit to carry out filtering on the signal; the filtered signal is sent into a control terminal of the industrial building fire fighting system through a signal emitter E1; and after being automatically calibrated, the signal is converted into an error correction signal of the control terminal of the industrial building fire fighting system.

A digital regulated Local Oscillator (LO) buffer receives an unregulated LO signal from a local oscillator to create a regulated LO signal. Embodiments include not only the digital regulated LO buffer, but also a transceiver and/or a receiver including at least one instance of the digital LO buffer. They may be implemented as an integrated circuit. The digital regulated LO Buffer may include: A LO buffer receiving the unregulated LO signal and an amplitude control signal to create the regulated LO signal. A peak detector receives the regulated LO signal to create an analog peak signal that is presented to a digital output comparator along with a reference amplitude signal to create a digital threshold detect signal. An amplitude controller receives the digital threshold detect signal to create a digital control signal that drives a digitally controlled source to create the amplitude control signal.

The invention provides a dedusting color sand vibrating screen. The dedusting color sand vibrating screen comprises a base and a screen box. A screen is arranged in the screen box. A vibration exciter is arranged on the screen box. The screen box comprises a screen box main body and limiting bodies located on the two sides of the main body. Spring supporting devices are arranged between the limiting bodies and a bottom plate. A support is arranged on the base. An exhaust device is arranged on the support and comprises an air duct extending outwards from the top of the screen box, a fan located in the air duct, and fan blades located at an air duct port. Each flan blade comprises a fan blade main body and a material crushing plate which is close to one side of the screen box and can rotate relative to the fan blade main body. A water pipe is arranged at the side end of the top of the main body. A water mist spray nozzle is arranged on the water pipe.

The invention discloses a parameter determination method and system for an extra-high voltage direct current cable superposition impact test device. The parameter determination method comprises the steps of guiding the type selection of a voltage source of the extra-high voltage direct current cable superposition impact test device according to the test demands of an extra-high voltage direct current cable test sample segment, analyzing the efficiency and characteristics of the extra-high voltage direct current cable superposition impact test device, and selecting a reasonable resistance-capacitance isolation device for parameter configuration. Parameters of the voltage generator and the impulse direct-current voltage isolation element in the extra-high voltage direct-current cable direct-current voltage superposition impulse test device are determined by performing parameter calculation on the extra-high voltage direct-current cable and performing circuit simulation on the direct-current superposition impulse voltage test device, so that effective isolation of impulse voltage and direct-current voltage is realized, the output efficiency of the direct-current superimposed impulse voltage test device is brought into full play, thereby guaranteeing that the amplitudes of impulse voltage and direct-current voltage on a cable sample meet test regulations, and satisfying the requirement for the test device when an extra-high-voltage direct-current cable is subjected to a direct-current superimposed impulse voltage test.

The invention provides a multi-line laser radar device and a light output power control method, the multi-line laser radar device comprises a plurality of laser emission assemblies, a plurality of laser receiving assemblies, an emission signal selection circuit, a receiving signal selection circuit, a controller and a feedback regulation circuit, the controller selects and drives the corresponding laser emission assemblies, and the feedback regulation circuit drives the corresponding laser emission assemblies. Echo signals of the corresponding receiving channels are obtained through the correspondingly-arranged laser receiving assemblies and the receiving signal selection circuit, the feedback adjusting circuit carries out signal processing on the echo signals, and high-voltage driving signals with the pulse width negatively correlated with the pulse width of the echo signals are output to the corresponding laser emitting assemblies. The output power of the laser pulse is automatically adjusted for objects to be measured with different reflectivity, the amplitude of the echo signal is ensured to be within a preset range, the stability of the echo signal is improved, the signal distortion is reduced, and the ranging precision is effectively improved while the laser receiving assembly is protected.

The invention provides a ceramic loudspeaker which comprises an upper shell, a lower shell, a PCB and a ceramic sheet. The upper shell and the lower shell are in butt joint, and the PCB and the ceramic sheet are bonded and attached to form a vibration assembly. The ceramic loudspeaker further comprises an installation plate located between a bottom plate of the lower shell and the upper shell, and the vibration assembly is bonded and attached to the top face or the bottom face of the installation plate. Due to the fact that the installation plate is located between the bottom plate of the lower shell and the upper shell, a distance exists between the installation plate and the bottom plate of the lower shell; besides, the vibration assembly is bonded and attached to the installation plate, and thus a distance exists between the vibration assembly and the bottom plate; in this way, when the ceramic loudspeaker is applied to a wearable intelligent device, the vibration assembly cannot make direct contact with the outside part such as the human body, and the amplitude of the ceramic loudspeaker is ensured, so that the sound pressure level and the tone quality clearness degree of the ceramic loudspeaker are increased, and the subjective listening effect is improved.

The invention discloses an aircraft pilot steering force sensor signal conditioning circuit, system and method, and the circuit comprises three groups of signal processing circuits, and the input endsof the three groups of signal processing circuits are respectively connected with the output ends of a steering column force sensor, a steering wheel force sensor and a pedal force sensor. The outputends of the three groups of signal processing circuits are connected with the input end of the flight parameter and audio recording system; the signal processing circuit comprises an input filter circuit, a first-stage amplification circuit, a second-stage amplification circuit and a second-order filter circuit which are connected in sequence. The driving force of a driver can be collected and recorded in real time, and a basis is provided for flight control state and flight fault judgment. Output signal processing circuits of the steering column force sensor, the pedal force sensor and the steering wheel force sensor are independent of one another and do not interfere with one another.