94results about How to "Prevent external electromagnetic interference" patented technology

The invention discloses an integrated optical isolation lightning electric field measurement apparatus, which integrates the measurement of fast change and slow change of a lightning electric field. The measurement apparatus mainly comprises an electric field receiving antenna, a signal conditioning circuit, an optical transmitter, an all-dielectric optical cable, an optical receiver and a signal acquisition and real-time processing terminal. The signal conditioning circuit and the optical transmitter are integrated to realize signal acquisition and photoelectric conversion and transmit an optical signal through the all-dielectric optical cable. The entire conditioning circuit and the optical transmitter are closed in a flat metal cylindrical box, and have high electromagnetic interference resistance. The optical receiver converts the received optical signal into an electrical signal which is subjected to compensation, correction and amplification and then output to a recording apparatus. A signal of which the change (slow change or fast change) is not measured is inverted by a system function inversion method according to a certain change (fast change or slow change) signal of the measured electric field. Apart from simple structure and small volume, the integrated optical isolation lightning electric field measurement apparatus, which adopts optical fiber transmission and is powered by lithium batteries, has the advantages of high reliability, high adaptability, high electromagnetic interference resistance, adjustable dynamic range of measurement and high precision.

A wireless communication frequency hopping method is disclosed and comprises the following steps: a plurality of wireless frequency points are preset, and a master terminal sends out predetermined format data; if return data from a slave terminal is received in preset time, communication connection is successfully established; otherwise the master terminal repeatedly sends out the preset format data and again confirm whether the return data from the slave terminal is received; if the return data from the slave terminal is not received when the times for which the master terminal sends out the preset format data reaches a preset number, the master terminal hops to another wireless frequency point and continues sending the preset format data after sleeping for a first time, and the preset format data sent from the main terminal is received by the slave terminal according to a fixed cycle; if the preset format data is received in a cycle, the data is returned to the master terminal, and communication with the master terminal is kept at corresponding frequency points; otherwise, the slave terminal hops to another wireless frequency point, and the master terminal and the slave terminal have a fixed frequency hopping sequence. The method is advantaged by simplicity, high efficiency and high reliability.

The present invention discloses a compression-resistant and wear-resistant coaxial cable. The coaxial cable comprises a rubber protective sleeve, a wear-resistant layer, wire cores and cable center bodies. One end of the inside of the rubber protective sleeve is provided with an external insulation layer, and the central location of the inside of the rubber protective sleeve is provided with the cable center bodies uniformly. The wire cores are uniformly arranged between the cable center bodies and the external insulation layer. The outside of each wire core is provided with a protective sleeve, the central location of the inside of each wire core is provided with conductors, and the outside of each conductor is provided with an internal crust. The other end of the inside of the rubber protective sleeve is provided with the wear-resistant layer, and a metal mesh layer is arranged between the wear-resistant layer and a buffer layer. According to the coaxial cable, by providing the buffer layer, a damping spring and reset springs uniformly arranged at the outside of each conductor, even if the coaxial cable is deformed under an external force, the coaxial cable can restore to the original state quickly after the external force is disappeared, and thus the cable can not be damaged.

The invention relates to the field of mechanical equipment condition monitoring, in particular to a metal particle detection sensor based on a high-frequency high-gradient magnetic field and a detection method thereof. The sensor comprises a sensor shell assembly, a magnetic field loop assembly and an oil pipe detection assembly. The sensor shell assembly comprises a shell, a first pipe connector and a second pipe connector, a through hole is formed in the side face of the shell, and the first pipe connector and the second pipe connector are arranged at through hole openings in the two sides of the shell respectively. The oil pipe detection assembly is located in the center of the shell and comprises an induction coil and an oil pipe, the oil pipe is located in an inner cavity of the sensor, the two ends of the oil pipe are connected with the first pipe connector and the second pipe connector in an embedded mode respectively, a groove is formed in the outer side of the pipe wall of the oil pipe, and the induction coil is wound in the oil pipe groove. The magnetic field loop assembly is located on the outer surface of the induction coil and comprises a first tank-shaped magnetic pole, a second tank-shaped magnetic pole and an excitation coil.

The invention discloses an in-phase alternating-current signal amplifying type gate drive system based on a logic protection emitter-coupled type. The in-phase alternating-current signal amplifying type gate drive system is mainly composed of a drive chip M, a self-locking optical excitation circuit, a drive circuit connected with the drive chip M and an in-phase alternating-current signal amplifying circuit arranged between the drive chip M and the self-locking optical excitation circuit. The in-phase alternating-current signal amplifying type gate drive system is characterized in that a logic protection emitter-coupled circuit is further connected between the output end of a NOR gate IC2 and the negative electrode output end of a NOR gate IC3 in series. According to the in-phase alternating-current signal amplifying type gate drive system, the relevant function of the drive chip M can be automatically excited according to external illumination condition, an extra starting device is not needed, and therefore the in-phase alternating-current signal amplifying type gate drive system is quite low in power consumption.

The invention discloses a novel gate drive system for blue LED lamps. The novel gate drive system mainly comprises a transformer T, a driver chip M, a switching current source, a diode D1, a capacitor C3, a resistor R7 and a transistor Q4, wherein the switching current source is serially connected between a VCC pin and an INP pin of the driver chip M, the diode D1 is serially connected between the VCC pin and a BOOST pin of the driver chip M, the capacitor C3 is serially connected between the BOOST pin and a TG pin of the driver chip M, the resistor R7 is serially connected between the TG pin and a TS pin of the driver chip M, a base electrode of the transistor Q4 is connected with the TG pin of the driver chip M, a collecting electrode of the transistor Q4 is grounded after passing by a capacitor C4 and a capacitor C5 sequentially, and an emitting electrode of the transistor Q4 is grounded. The novel gate drive system for the blue LED lamps has the functions of short-circuit protection, overvoltage protection and open-circuit protection and is low in power consumption, and starting time of the novel gate drive system is one fourth of that of a traditional gate drive circuit.

The invention discloses an LED lamp protection system based on a logic protection emitter-coupled amplifying circuit, mainly composed of a transformer T, a driving chip M, a switching current source connected in series between a VCC pin and an INP pin of the driving chip M, a capacitor C3 connected in series between a BOOST pin and a TG pin of the driving chip M, a resistor R7 connected in series between the TG pin and a TS pin of the driving chip M, and a transistor Q4 of which the base is connected with the TG pin of the driving chip M, the collector is grounded sequentially through a capacitor C4 and a capacitor C5, and the emitter is grounded. The LED lamp protection system is characterized in that a logic protection emitter-coupled amplifying circuit is connected in series between the VCC pin and the BOOST pin of the driving chip M. The LED lamp protection system of the invention not only has the functions of short-circuit protection, over-voltage protection and open-circuit protection, but also has very low power consumption. Moreover, the starting time is only 1 / 4 of that of a traditional gate driving circuit.

The invention discloses a double-power amplification type drain electrode driving system for an LED lamp with blue rays. The system mainly consists of a partial pressure switch circuit, a control switch circuit connected with the output end of the partial pressure switch circuit, a nonlinear trigger circuit arranged at the output end of the control switch circuit, and a power amplifying circuit arranged at the output end of the nonlinear trigger circuit. The system is characterized in that a light beam excitation type logic amplifying circuit and a logic protection emitter coupling type amplifying circuit are also connected between the partial pressure switch circuit and the power amplifying circuit in series. According to the system, the nonlinear trigger circuit, the power amplifying circuit and the light beam excitation type logic amplifying circuit are combined for use creatively, so that the nonlinear characteristic of the nonlinear trigger circuit can be ensured, the safe and reliable trigger voltage can also be supplied to the power amplifying circuit, the interference of electromagnetic pulses can be obviously reduced, and the stable performance of the power amplifying circuit can be ensured.

The invention discloses a gate drive system based on a logic protection amplifying circuit. The gate drive system mainly comprises a switch current source, a transformer T, a drive chip M, a diode D1, a capacitor C3 and a resistor R7, wherein the diode D1 is serially connected between a VCC pin and a BOOST pin of the drive chip M, the capacitor C3 is serially connected between the BOOST pin and a TG pin of the drive chip M, and the resistor R7 is serially connected between the TG pin and a TS pin of the drive chip M. The gate drive system is characterized in that the logic protection amplifying circuit is serially connected between the drive chip M and a switch power amplifying circuit. The gate drive system has the advantages that functions of short circuit protection, overvoltage protection and open circuit protection are realized, low power consumption is achieved, and starting time of the gate drive system is only 1 / 4 of that of a traditional gate drive circuit; moreover, owing to the switch power amplifying circuit, power signals inputted into the drive chip M can be guaranteed against attenuation so as to guarantee integral performance stability.

The invention discloses an in-phase alternating current signal amplification type optical excitation grid drive circuit mainly composed of a drive chip M, a self-locking optical excitation circuit and a drive circuit, and the drive circuit is connected with the drive chip M. The in-phase alternating current signal amplification type optical excitation grid drive circuit is characterized in that an in-phase alternating current signal amplification circuit is connected between the drive chip M and the self-locking optical excitation circuit in series; the in-phase alternating current signal amplification circuit is composed of a power amplifier P, a resistor R4, a resistor R5 and the like, one end of the resistor R4 is connected with a VCC pin of the drive chip M, the other end of the resistor R4 is connected with the positive electrode input end of the power amplifier P, one end of the resistor R5 is connected with the negative electrode input end of the power amplifier P, and the other end of the resistor R5 is connected with the self-locking optical excitation circuit. The related functions of the drive chip M are automatically excited according to external light conditions, additional starting devices do not need to be added, and therefore the power consumption of the drive circuit is reduced.

An optical image anti-shake device with a yoke is provided. The optical image anti-shake device includes: a casing having a first aperture; a fixing portion having a bottom plate, the bottom plate having a second aperture corresponding in position to the first aperture; and an active portion enclosed by the casing and resiliently clamped between the casing and the bottom plate by the fixing portion, the active portion including: a correcting module for correcting, with a magnetic force, a blur of images caused by a shake of the optical image anti-shake device; a frame having a receiving space; a lens holder disposed in the receiving space of the frame; a lens unit corresponding in position to the first aperture and the second aperture, the lens unit being carried by the lens holder and having an image-capturing optical axis; and a yoke fixed to the frame.

The invention discloses a mixed type grid driving system which is mainly composed of a driving chip M, a driving circuit, a same-phase alternating current signal amplifying circuit, a self-locking light exciting circuit, a bootstrapping circuit and a power driving amplifying circuit, wherein the driving circuit is connected with the driving chip M, the same-phase alternating current signal amplifying circuit is connected with the driving chip M, the self-locking light exciting circuit is connected with the same-phase alternating current signal amplifying circuit, the bootstrapping circuit is connected with the self-locking light exciting circuit, and the power driving amplifying circuit is arranged between the self-locking light exciting circuit and the driving chip M. The mixed type grid driving system is characterized in that the mixed type grid driving system is further provided with a light beam exciting logic amplifying circuit and a logic protective emitter-coupled type amplifying circuit, wherein the light beam exciting logic amplifying circuit is connected with the bootstrapping circuit, the self-locking light exciting circuit and the power driving amplifying circuit respectively, and the logic protective emitter-coupled type amplifying circuit is connected between the power driving amplifying circuit and the driving chip M in series. The related functions of the driving chip M are excited automatically by the mixed type grid driving system according to external lighting conditions, a starter does not need to be arranged additionally, and therefore power consumption is extremely low. Meanwhile, the starting time of the mixed type grid driving system is only one fourth of that of a traditional grid driving circuit, and the stating time of the mixed type grid driving system is extremely short.

The invention discloses a grid drive system for an LED lamp protection system. The grid drive system is characterized by mainly comprising a transformer T, a drive chip M, a switchable current source connected between a VCC pin and an INP pin of the drive chip M in series, a diode D1 connected between the VCC pin and a BOOST pin of the drive chip M in series, a capacitor C3 connected between the BOOST pin and a TG pin of the drive chip M in series, a resistor R7 connected between the TG pin and a TS pin of the drive chip M in series, and a transistor Q4, wherein the base of the transistor Q4 is connected with the TG pin of the drive chip M, the collector of the transistor Q4 is grounded after passing through a capacitor C4 and a capacitor C5, and the emitter of the transistor Q4 is grounded. The grid drive system for the LED lamp protection system not only has the short circuit protection, over-voltage protection and open circuit protection functions, but also is low in power consumption, and the starting time of the system is only one fourth that of a traditional grid drive circuit.

The invention discloses a Blue-LED lamp nonlinear drain electrode drive system based on a logic protection amplifying circuit. The blue-LED lamp nonlinear drain electrode drive system is mainly composed of a voltage-distributing switching circuit, a control switching circuit, a nonlinear triggering circuit and a power amplifying circuit, wherein the control switching circuit is connected with the output end of the voltage-distributing switching circuit, the nonlinear triggering circuit is arranged at the output end of the control switching circuit, and the power amplifying circuit is arranged at the output end of the nonlinear triggering circuit. The blue-LED lamp nonlinear drain electrode drive system based on the logic protection amplifying circuit is characterized in that the logic protection amplifying circuit is further connected between the nonlinear triggering circuit and the power amplifying circuit in series. According to the Blue-LED lamp nonlinear drain electrode drive system based on the logic protection amplifying circuit, the nonlinear triggering circuit and the power amplifying circuit are creatively used together, the nonlinearity of the nonlinear triggering circuit can be guaranteed, a safe and reliable triggering voltage can be also provided for the power amplifying circuit, the interference of electromagnetic pulse can be remarkably reduced, and the stable performance of the power amplifying circuit can be guaranteed.