49results about How to "Not easy to electromagnetic interference" patented technology

There is provided a common mode filter capable of allowing an ultrahigh speed differential signal to transmit and hardly allowing a common mode noise to transmit, comprising: a lumped-constant differential delay line DL formed by arranging inductors Lo, being passive series elements, and capacitors Co, being passive parallel elements, in a ladder-shaped differential four terminal network composed of the passive series elements and the passive parallel elements arranged in the differential lines 1, 3. In the lumped-constant differential delay line DL, the capacitors Co, being the parallel elements, are formed of two capacitors connected in series equivalent to each other and having same values with each other such as Co / 2 and Co / 2, or Co and Co. Inductors L1 to L4 and resistors R1 to R4 for attenuating the common mode noise are connected between connection points T1 to T4 of the capacitors Co / 2 or Co connected in series, and a ground potential, thus forming a common mode noise attenuating series resonance circuit together with the capacitors Co / 2, Co.

The invention belongs to liquid level measurement, in particular relates to a photonic crystal fiber optic liquid level sensor and a system formed by same. The photonic crystal fiber optic liquid level sensor is characterized by comprising a single mode fiber SMF-28 and a photonic crystal fiber SC-4.0, wherein the single mode fiber SMF-28 is fused with the beginning end of the photonic crystal fiber SC-4.0; a beginning end cladding air hole of the photonic crystal fiber is closed at a fusing point to form a beginning end complete collapsing area; the length of the beginning end complete collapsing area is equal to 65 mu m; a fusing machine is used for charging the tail end of the photonic crystal fiber to form a tail end collapsing area; and a reflecting film is plated on the tail end of the photonic crystal fiber. The whole sensor is completely made of optical fibers and has convenient manufacture and no need of optical fiber corrosion. The sensing system is free from the influence of stray light and temperature and has the advantages of less signal noise, high system sensitivity and high reliability.

The invention discloses an information theft-preventing protecting device of financial self-service equipment and a working method thereof. The device comprises a shell, a laser distance measuring module, a control module and an interface module, wherein the laser distance measuring module, the control module and the interface module are installed in the shell; the optical axis of the laser distance measuring module aligns to a card reader on the financial self-service equipment and the periphery thereof; a circuit of the laser distance measuring module is electrically connected with the control module and the interface module sequentially; and the interface module is electrically connected with an external alarm system. When the device is operated, firstly, a precise distance parameter value between an installation point and a card reader of a laser emitting device is measured and used as an alarm distance parameter threshold value; then, measuring light beams are periodically projected to the periphery of the card reader, and the judgment is carried out according to the received measuring distance parameter and the preset early warning time parameter. When the measuring distancevalue exceeds the alarm distance parameter threshold value, the physical state or form at the periphery of the card reader is changed, and the alarm is given according to the set situation. The invention can effectively eliminate the phenomena of false alarm and missing alarm without changing the self-service equipment.

The invention relates to a multi-parameter measurement probe and a measurement method for on-orbit tiny space debris, belonging to the field of space debris monitoring and measurement, and relates to a method for measuring multiple parameters of size, velocity and mass of on-orbit passive tiny debris, which is used for spacecraft In-orbit space debris measurement payload. The invention includes front and rear thin film sensors, front and rear charge collection electrodes, charge measurement amplifiers and high frequency pulse counters. The front and rear films are plated with metal films, and there are equal-spaced charge collection wires behind the front film and in front of the back film. A negative DC voltage is applied between the collection electrode and the film to collect the charge signals generated by the impact of tiny fragments on the front and rear films. The charges generated by the front and rear films are collected by the collecting electrodes, and amplified into voltage pulse signals by the charge amplifier. The high-frequency pulse counter measures the time difference between the impact signals on the front and rear films to obtain speed and direction information. The energy of the impact debris is obtained from the charge signal, and the mass of the space debris can be obtained by combining the velocity.

The invention discloses a great-angle tilted fiber bragg grating mechanical vibration sensing array and a great-angle tilted fiber bragg grating mechanical vibration sensing system. The great-angle tilted fiber bragg grating mechanical vibration sensing array comprises an optical fiber core, and is characterized in that: the front section of the optical fiber core is provided with a 45-degree tilted fiber bragg grating, and the 45-degree tilted fiber bragg grating serves as a polarizer of a great-angle tilted fiber bragg grating vibration sensor; an included angle between tilted grating stripes of the tilted fiber bragg grating and an optical fiber cross section is 45 degrees; the middle section of the optical fiber core is provided with N great-angle tilted fiber bragg gratings, and N is a natural number greater than or equal to 1; grating stripes of the N great-angle tilted fiber bragg gratings are parallel to one another, and an included angle between the tilted grating stripes of each great-angle tilted fiber bragg grating and the optical fiber cross section ranges from 79 to 84 degrees; and the outer surface of an optical fiber cladding corresponding to each great-angle tilted fiber bragg grating is provided with an elastic membrane. The great-angle tilted fiber bragg grating mechanical vibration sensing array and the great-angle tilted fiber bragg grating mechanical vibration sensing system can be widely used in the fields of optical fiber perimeter and structural safety monitoring, landslide early warning and the like.

The invention relates to an electronic horn for a motor vehicle or a motor boat. The electronic horn for the motor vehicle or the motor boat comprises a booster circuit, a piezoelectric induction unit, a feedback circuit and a horn unit, wherein the booster circuit is used for carrying out boost processing on input voltage to generate boosted driving voltage, the piezoelectric induction unit is used for receiving the driving voltage generated by the booster circuit to drive a vibrating diaphragm of the horn unit to vibrate so as to give out a sound, and generating induction voltage with the oscillation frequency, the feedback circuit is used for receiving the induction voltage, and building oscillation switch-on and switch-off according to the induction voltage to control the working state of the booster circuit, the horn unit is used for vibrating to give out a sound together with the piezoelectric induction unit when the piezoelectric induction unit is driven by the driving voltage, when operation is carried out, the feedback circuit is controlled by the induction voltage to carry out switch-on and switch-off according to the oscillation frequency, and the booster circuit generates the driving voltage with the oscillation frequency. The electronic horn for the motor vehicle or the motor boat is high in electroacoustic conversion efficiency, improves the energy utilization rate, and is beneficial to energy saving and environmental protection.

The invention discloses a 10KV cable joint protecting device. The device comprises a shell body buried in a soil body, a partition plate structure arranged in the shell body and an explosion suppression device; a cable connecting cavity is formed in the shell body; the cable connecting cavity is transversely divided into two cable containing cavities and a middle cavity located in the middle by the partition plate structure; the middle cavity is divided into an upper layer and a lower layer; the lower layer of the middle cavity is a joint protection box and is uniformly divided into a plurality of joint protection sub-cavities in the longitudinal direction; the upper layer of the middle cavity is an explosion-proof cavity; sub-cavity openings which communicate with the joint protection sub-cavities in a one-to-one correspondence mode are formed in a joint protection cover; each sub-cavity opening is connected with a sub-cavity cover through a spigot structure in a covered mode; the bottom of each sub-cavity cover is provided with an explosion-proof box through a joint connecting frame; and an energy release hole is downward. Through the explosion-proof cavity, the impact generatedby explosion is effectively reduced, and a cable joint is prevented from damaging the side walls of the joint protection sub-cavities to damage an adjacent cable joint.