82results about How to "Prevent electromagnetic leakage" patented technology

A wireless IC device includes a wireless IC chip, a power supply circuit board upon which the wireless IC chip is mounted, and in which a power supply circuit is provided, the power supply circuit includes a resonant circuit having a predetermined resonant frequency, and a radiation pattern, which is adhered to the underside of the power supply circuit board, for radiating a transmission signal supplied from the power supply circuit, and for receiving a reception signal to supply this to the power supply circuit. The resonant circuit is an LC resonant circuit including an inductance device and capacitance devices. The power supply circuit board is a multilayer rigid board or a single-layer rigid board, and between the wireless IC chip and the radiation pattern is connected by DC connection, magnetic coupling, or capacitive coupling.

A wireless IC device includes a wireless IC chip, a power supply circuit board upon which the wireless IC chip is mounted, and in which a power supply circuit is provided, the power supply circuit includes a resonant circuit having a predetermined resonant frequency, and a radiation pattern, which is adhered to the underside of the power supply circuit board, for radiating a transmission signal supplied from the power supply circuit, and for receiving a reception signal to supply this to the power supply circuit. The resonant circuit is an LC resonant circuit including an inductance device and capacitance devices. The power supply circuit board is a multilayer rigid board or a single-layer rigid board, and between the wireless IC chip and the radiation pattern is connected by DC connection, magnetic coupling, or capacitive coupling.

The present application describes various embodiments regarding systems and methods for providing a lightweight and durable portable computing device having a thin profile. The portable computing device can take the form of a laptop computer. The laptop computer can include a uni-body top case having an integrated support system formed therein, the integrated support system providing structural support that distributes applied loads through the top case preventing warping and bowing.

The invention relates to a time-domain calibration method for an electromagnetic pulse magnetic-field probe. The method is used for calibrating an electromagnetic pulse magnetic-field probe in the time domain. The method comprises an anechoic chamber, a pulse signal source, a transmitting antenna, a standard receiving antenna, and a digital oscilloscope. According to the method, the transmitting antenna and the standard receiving antenna are placed at fixed places in the anechoic chamber, and the pulse signal source and the digital oscilloscope are placed in an anechoic chamber control room. A pulse voltage signal is fed into the transmitting antenna via a through-wall cable by the pulse signal source, and the transmitting antenna radiates an electromagnetic pulse to the outside. The standard receiving antenna receives the pulse electric field radiated from the transmitting antenna. The digital oscilloscope is connected with the receiving antenna and a to-be-calibrated magnetic-field probe via another through-wall cable so as to record a voltage signal waveform measured by the receiving antenna and the to-be-calibrated magnetic-field probe. Measured voltage signals are processed based on a certain algorithm, so that the time-domain transfer function of the to-be-calibrated magnetic-field probe is obtained. In this way, the time-domain calibration on the electromagnetic pulse magnetic-field probe can be realized.

The invention relates to the technical field of wave-absorbing materials, in particular to a preparation method of a silicon carbide / carbon hollow porous microsphere wave-absorbing material. The invention aims to solve the technical problems of large particle size and easy agglomeration of silicon carbide particles in the silicon carbide / carbon composite material prepared by the existing method. The method includes: mixing deionized water, anhydrous ethanol and ammonia water, adding a surfactant, resorcinol, a silicon source and a formaldehyde solution, stirring the substances uniformly at room temperature, then adding melamine, performing stirring, transferring the mixture into a high-temperature and high-pressure reactor for reaction, and conducting high temperature calcination; and thenperforming mixing with magnesium powder, conducting high temperature calcination in a nitrogen atmosphere, washing off redundant magnesium powder with hydrochloric acid, and carrying out washing anddrying. The silicon carbide / carbon hollow porous microsphere obtained by the method has good chemical homogeneity and large specific surface area, and can effectively avoid agglomeration and sinteringof silicon carbide particles. The material prepared by the method provided by the invention is used for making light and efficient wave-absorbing coatings.

The invention discloses a formula of electromagnetic wave shielding paint and a preparation method thereof. It is mainly based on nickel powder with excellent oxidation resistance, adding ferrite powder as a wave-absorbing material, together with epoxy resin, film-forming aids, coupling agents, dispersants, etc., to make water-soluble coatings. Above 23MPa, it can achieve 55dB-75dB shielding effectiveness for electromagnetic waves in the frequency range of 40MHz-18GHz.

The invention discloses a four-frequency dual-polarized antenna and a wireless communication device. The four-frequency dual-polarized antenna comprises a first metal layer, a first substrate integrated waveguide, a second metal layer, a second substrate integrated waveguide and a metal floor which are arranged in sequence from top to bottom, wherein the first metal layer is provided with a rectangular ring radiation gap; the middle portion of the second metal layer is provided with a cross-shaped coupling gap; rectangular coupling gaps are respectively arranged at four sides of the cross-shaped coupling gap, the middle portion of the second substrate integrated waveguide is provided with a feed through hole, and the metal floor is provided with a circular gap arranged on the correspondingposition of the feed through hole; and the wireless communication device comprises the antenna mentioned above. The antenna employs the coaxial feed excitation mode to couple the energy at the upperportion through different coupling gaps and from different paths and radiate the energy by the rectangular ring radiation gap, and the antenna is compact in structure, low in profile and stable in radiation pattern and can achieve simple and adjustable four-frequency dual-polarized performances.

The invention discloses a non-flange waveguide connecting structure, which comprises a male connecting part and a female connecting part, and is characterized in that the male connecting part comprises a first waveguide and a periodic metal convex body array, wherein the periodic metal convex body array is arranged on the peripheral surface of the outer wall of the tail end of the first waveguide,and a plurality of metal convex bodies are respectively and uniformly arranged according to a periodic layout rule; the female connecting part comprises a second waveguide and an expanded cavity structure; the expanded cavity structure is arranged at the tail end of the second waveguide, and the end, provided with the periodic metal convex body array, of the male connecting part is inserted intothe expanded cavity structure of the female connecting part to form the whole non-flange waveguide connecting structure. Compared with a traditional waveguide flange, the non-flange waveguide connection structure provided by the invention has the advantages that the size is greatly reduced, the structure layout is more facilitated, and more convenient and flexible assembly can be realized throughthe pluggable design.

A wireless IC device includes a wireless IC chip, a power supply circuit board upon which the wireless IC chip is mounted, and in which a power supply circuit is provided, the power supply circuit includes a resonant circuit having a predetermined resonant frequency, and a radiation pattern, which is adhered to the underside of the power supply circuit board, for radiating a transmission signal supplied from the power supply circuit, and for receiving a reception signal to supply this to the power supply circuit. The resonant circuit is an LC resonant circuit including an inductance device and capacitance devices. The power supply circuit board is a multilayer rigid board or a single-layer rigid board, and between the wireless IC chip and the radiation pattern is connected by DC connection, magnetic coupling, or capacitive coupling.

The present invention provides a shield structure for an electronic device allowing conductive members to be connected electrically to each other at low impedance while preventing the leakage of electromagnetic waves effectively. The first conductive member and the second conductive member for enclosing the electronic device respectively have laid portions that are laid one on the other and fastened to each other at plural positions by means of screw members. Through-holes into which the screw members are to be inserted are formed on both of the laid portions. Protruding portions, which protrude toward the laid portion of the second conductive member, each are formed between the adjacent through-holes on the laid portion of the first conductive member. The protruding portions each have a shape extending in the direction connecting the adjacent through-holes and bulging from both ends toward the center thereof in a smooth curve.

The invention discloses an intelligent wireless charging type battery electric vehicle charging pile. The charging pile comprises a shell and an electromagnetic transmitting coil installed inside magnetic induction coils of a battery electric vehicle. One side of the shell is provided with a circular installation hole. A disc is installed inside the circular installation hole. The center of the disc is provided with a circular accommodating slot. A photoelectric switch is installed on the axial center of the bottom inner wall of the circular accommodating slot. The electromagnetic transmitting coil is installed along the sidewall of the circular accommodating slot. The two horizontal sides of the circular accommodating slot are provided with detection coil installation holes. The magnetic induction coils are installed inside the detection coil installation holes. A display screen is installed above the circular installation hole. A buzzer is installed on one side of the display screen. A flashing light is installed on the top of the shell. A controller is installed inside the shell. With the charging pile adopted, parking position offset of battery electric vehicles during charging is avoided, electromagnetic leakage of battery electric vehicles during charging is avoided, the charging efficiency of battery electric vehicles is improved, and energy waste is prevented.

The invention relates to the field of electronic communication equipment, in particular to a sealed shielded power network protection cabinet. The cabinet comprises a cabinet body, a cabinet door, a voltage stabilizer, a circuit breaker, a contactor, a transformer, a relay, a current Hall transformer, a switch power supply, a digital board, an analog board and a connecting terminal. A transition chamber is arranged outside the cabinet door; and a foaming plastic layer, a metal shielding layer and an elastic foam layer are arranged in the plates of the cabinet body, the cabinet door and the transition chamber respectively. The transition chamber and the cabinet body are connected integrally to encircle the cabinet door, and a sealed door is arranged on the transition chamber. The metal shielding layers added in the plates of the cabinet body and the cabinet door can effectively prevent electromagnetic radiation and electromagnetic leakage, obviously improve the positioning reliability, improve the production efficiency and ensure system safety and power supply quality safety; and the transition chamber can greatly improve the protective tightness.

The present invention discloses an electromagnetic shielding cover, comprising a shielding frame and a shielding lid. The shielding lid is made from a metallic conduction shielding adhesive tape. The shielding frame is adhered to the surface of the shielding cover. The shielding cover has the advantages that the shielding cover can reduce the material cost, the labor cost and the quality inspection cost of the manufacture, the size of the shielding cover can be reduced, the electromagnetic leakage due to the gap between the shielding lid and the shielding cover can be avoided, and the handling operation is simple and convenient.

The invention relates to a wire terminal connecting device comprising a shield shell body and at least one terminal, wherein a conductive structure is arranged in the shield shell body, a matching part extends from the shield shell body along the matching direction and is provided with an insulation shell body, the at least one terminal is arranged in the insulation shell body, the shield shell body is provided with a matching side edge along the matching direction, a conductive elastic piece is arranged on the matching side edge of the shield shell body, and the conductive elastic piece is in electrical connection with the conductive structure in the shield shell body. The invention further relates to a plate terminal connecting device comprising a conductive outer shell and a connecting device shell body located in the conductive outer shell, wherein at least one terminal is arranged on the connecting device shell body, the conductive outer shell limits a matching part which is provided with a matching side edge along the matching direction, a conductive elastic piece is arranged on the matching side edge of the matching part, and the conductive elastic piece is in electrical connection with the conductive outer shell. Besides, the invention further relates to a corresponding plate terminal connecting device assembly and a corresponding connecting device assembly.

The invention relates to the field of electric communication equipment, in particular to a shielded power grid protective cabinet. The cabinet comprises a cabinet body, a cabinet door, a voltage stabilizer, a breaker, a contactor, a transformer, a relay, a current Hall transformer, a switch power supply, a digiboard, an analog board and a wiring terminal, wherein the board structure of the cabinet body and the cabinet door is formed by a steel plate layer, a foaming plastic layer, a metal shielding layer, a flexible foam layer and an insulating shell layer successively from inside to outside, wherein an air conditioner is arranged on the top of the cabinet body, and an insulating earthing lead wire is arranged on the bottom of the cabinet body. The metal shielding layer is added between the cabinet body board and the cabinet door board, so that electromagnetic radiation and electromagnetic leakage can be effectively prevented, positioning reliability can be remarkably improved, production efficiency can be improved, and system safety and quality safety of power supply can be ensured.

The invention provides a low-noise attenuator based on a microwave directional coupler. The low-noise attenuator based on the microwave directional coupler adopts a four-port microwave directional coupler as a low-noise attenuator. The four-port microwave directional coupler is made of a low-temperature superconducting metal material; the four-port microwave directional coupler is provided with amicrowave signal input port, a microwave signal straight-through port, a microwave signal coupling port and a microwave signal isolation port; the microwave signal straight-through port is connected with a microwave matching load; the microwave signal isolation port is short-circuit, so that most of the signals coupled to the microwave signal isolation port from the microwave signal input port areshort-circuit to the microwave signal coupling port, and the rest of the signals return to the microwave signal input port and the microwave signal straight-through port; the amplitude of the microwave signal input port coupled to the microwave signal coupling port meets the set microwave signal attenuation requirement; the low noise attenuator is placed in a low temperature environment of a K level. The low-noise attenuator based on a microwave directional coupler can only generate thermal noise equivalent to that generated by the attenuator under the extremely low temperature condition onlyby a low temperature environment without the extremely low temperature condition.

The invention provides an automatic charging device of an AGV and aims to avoid a short circuit phenomenon generated because of cell anode and cathode reverse connection caused by AGV reverse driving-in operation during charging. The automatic charging device comprises a vehicle charging unit, wherein the vehicle charging unit comprises a bottom board and a vehicle electrode fixed on the bottom board. The automatic charging device is characterized in that the charging device further comprises a lifting turning device and a polarity detection device, the lift turning device comprises a first electric cylinder and a first motor used for driving the first electric cylinder to rotate, a telescopic rod of the first electric cylinder is fixedly connected with the bottom board, the polarity detection device comprises a second electric cylinder and a second motor used for driving the second electric cylinder to rotate, a tail end of a telescopic rod of the second electric cylinder is provided with a polarity detection copper plate, the bottom board is provided with an arc-shaped demising groove, the second electric cylinder penetrates through the arc-shaped demising groove, and an arc angle of the arc-shaped demising groove is greater than 180 DEG.

The invention discloses a radio frequency front end with high stability, and belongs to the technical field of radio frequency front ends. The radio frequency front end comprises a multi-layer circuitboard, chips, a vertical transition structure and a dielectric enclosure frame, and realizes the high-stability work of the radio frequency front end under high-frequency and high-integration requirements. The multi-layer circuit board is a multi-layer dielectric plate comprising a radio frequency transmission line layer, a control line layer, a power supply network layer and an isolation groundlayer, and is connected with the chips through solder balls and a heat dissipation substrate to realize electrical and thermal transmission. The chips are a power amplifier, an LNA, a radio frequencyswitch, an amplitude-phase control chip, a power divider chip and the like. The vertical transition structure is a vertical metal connecting hole connected with a strip-shaped transmission line, the dielectric material of the dielectric enclosure frame is the same as that of the multi-layer circuit board, vertical metal grounding holes are formed in the periphery of the dielectric enclosure frame,and the dielectric enclosure frame is prepared on the periphery of a chip cavity to form an isolation boundary with a certain height. According to the invention, the performance and the working stability of the radio frequency front-end module and the application system are effectively improved.

The invention discloses a ruggedized computer display screen electromagnetic compatibility processing method, and belongs to the display screen electromagnetic compatibility processing technology field. The problems are solved that electromagnetic leakage is easy to cause and the electromagnetic shielding reliability is lowered during display screen electromagnetic compatibility processing. The technical scheme is as follows: a structural form combined with a liquid crystal screen front cover, an electromagnetic shielding conducting adhesive, a shielding silk screen and conductive foam is employed, and the method comprises the following steps: firstly, a boss is reserved in a position, where shielding glass is installed, of the liquid crystal screen front cover, and a square groove is processed on the boss; secondly, the shielding glass exposed from the shielding silk screen is fixed on the liquid crystal screen front cover by conductive double faced adhesive tapes, and the shielding and the boss are level; thirdly, the electromagnetic shielding conducting adhesive is painted inside the square groove; fourth, one side, with a binder, of the conductive foam is connected with the shielding silk screen, the shielding silk screen is pressed into the square groove in a manner of pressing the conductive foam, and after the electromagnetic shielding conducting adhesive is cured, tight contact of the shielding silk screen and the shielding glass is achieved.

The invention relates to a microwave heating film device and system, the microwave heating film device comprises a rectangular waveguide and a compression ridge, the compression ridge is arranged in a cavity of the rectangular waveguide, a dielectric plate is arranged on the compression ridge, the compression ridge and a to-be-heated film are separated to form a gap, and electromagnetic waves pass through the gap after being compressed by the compression ridge; the rectangular waveguide is provided with an anti-leakage device, and the anti-leakage device absorbs / blocks leakage of electromagnetic waves in the cavity; and a ventilation structure is arranged in the rectangular waveguide, and hot air and moisture in the cavity are brought out of the cavity through the ventilation structure. The objective of the invention is to change the original electric field distribution in the waveguide through the dielectric plate arranged on the T-shaped ridge waveguide, and achieve the heating of a lossy dielectric film attached to the metal surface through microwaves.

The invention provides an electromagnetic shielding film preparing method. The method comprises the steps that a carrier film layer is provided, and an insulating layer is prepared on the carrier filmlayer; conductive treatment is carried out on the insulating layer through vacuum plating; an insulating layer matrix after conductive treatment is placed in an alkaline electrolyte, and at least three times of electroplating sedimentation is carried out on the surface of the conductive matrix by using an alkaline liquor precipitation method to prepare a metal shielding layer; the metal shieldinglayer is placed in a micro-etching solution, and surface micro-etching is carried out to acquire a micro-etched layer; the micro-etched metal shielding layer is placed in an acidic electrolyte, and acid liquid sedimentation is carried out at least once to prepare a foamed metal layer; and a conductive adhesive layer and a protective film layer are sequentially prepared on the surface of the foamed metal layer to acquire an electromagnetic shielding film.

The invention relates to a flat cable used for a computer display, and belongs to the computer connecting line technology field. The flat cable used for the computer display comprises a plurality of conductors, which are arranged at certain intervals; and an insulation layer, which is disposed on the peripheries of the conductors in a covered manner. The plurality of conductors and the insulation layer are used to form a cable main body, and the conductors comprises two grounding conductors disposed on the end parts, and a plurality of signal transmission conductors disposed between the two grounding conductors. The outer part of the cable main body is provided with a copper foil layer, and an insulation covering layer used for covering the copper foil layer. The grounding conductors are electrically connected with the copper foil layer, and the oxidation treatment of the copper foil layer can be carried out. The flat cable used for the computer display is advantageous in that the flexibility is good, and the shielding performance can be improved, and the electromagnetic leakage can be effectively prevented, and therefore the requirements of the display on the miniaturization performance, the thinning performance, and the flexibility performance can be satisfied.

The invention discloses an induction-type tank welding seam drying and heating device which comprises a heating circuit and a heating body, wherein the heating body comprises a bottom frame, an upper cover, a temperature sensor, a fan, microcrystalline glass, a coil plate and a magnetic block; and the heating circuit comprises an induction heating inverter major loop and a control circuit. In the device provided by the invention, the high-frequency induction vortex thermal effect technology is applied to the tank welding seam drying device first domestically, and the technologies of embedded-type loop control, full-cavity shield thick film integrated circuit design, electromagnetic compatible design and the like are integrated first, and a full-cavity shield structure design technology of metal outer shell shield, multi-layer printed board, twisted shield cable, embedded molding magnetic strips and the like is adopted first.

The invention provides a positioning method and system for a shielding shell hole seam position. The positioning method for the shielding shell hole seam position includes the step S101 of focusing on electromagnetic waves transmitted by the shielding shell hole seam through a focusing device, the step S102 of receiving electromagnetic waves in different positions within the focused electromagnetic wave range through an electromagnetic wave receiving device, the step S103 of converting the electromagnetic waves received by the electromagnetic wave receiving device into electromagnetic energy values through an optical recording device and recording the electromagnetic energy values, the step S104 of comparing the electromagnetic energy values through an analysis device to obtain the maximum electromagnetic energy value and determining the position of the obtained maximum electromagnetic energy value, and the step S105 of locating the shielding shell hole seam position through the position of the maximum electromagnetic energy value. According to the positioning method and system for shielding shell hole seam position, micro-hole seams can be accurately positioned, and electromagnetic leakage of a shielding shell can be effectively prevented.

The invention provides a cabinet capable of electromagnetic shielding. The cabinet comprises a shielding cabinet body, a cable assembly and a connector, the connector is in connection and communication with external equipment of the shielding cabinet body, the connector is connected with the output end of the cable assembly, a shielding layer of the cable assembly is provided with a flange assembly which prevents the shielding layer from electromagnetic leakage, the shielding cabinet body is provided with through holes through which the cable assembly penetrates, and the flange assembly is mounted at the positions of the through holes in a sealed manner. The cabinet can prevent transmission signals from interference, and the installation position of the connector can be changed.

The invention discloses a terahertz radial power distribution / synthesis network with a multilayer structure, and belongs to the technical field of terahertz power synthesis, the terahertz radial power distribution / synthesis network comprises an input rectangular waveguide, an input mode converter, a multilayer structure, an output mode converter and an output rectangular waveguide which are connected in sequence, the multilayer structure comprises M layers, a radial power divider / synthesizer and N bent waveguides arranged along the outer side of the radial power divider / synthesizer at equal included angles are arranged between the (M-1) th layer and the Mth layer, the third layer to the (M-2) th layer are detachable structures, N functional structures for realizing power amplification or / and frequency multiplication are arranged between the third layer and the (M-2) th layer, and each first bent waveguide is connected with the corresponding second bent waveguide through the corresponding functional structure. According to the invention, the functional chip can be debugged and replaced without influencing other structures, the module has great flexibility in module maintenance and engineering application, the assembly difficulty is reduced, and the module is suitable for power synthesis and module packaging of the terahertz frequency band.

The invention provides a cabinet capable of electromagnetic shielding. The cabinet comprises a shielding cabinet body, a cable assembly and a connector, the connector is in connection and communication with external equipment of the shielding cabinet body, the connector is connected with the output end of the cable assembly, a shielding layer of the cable assembly is provided with a flange assembly which prevents the shielding layer from electromagnetic leakage, the shielding cabinet body is provided with through holes through which the cable assembly penetrates, and the flange assembly is mounted at the positions of the through holes in a sealed manner. The cabinet can prevent transmission signals from interference, and the installation position of the connector can be changed.

The invention discloses an electromagnetic oven. The electromagnetic oven comprises a housing, a panel, a control circuit board, a coil disc and a magnetic stripe device arranged inside the coil disc,wherein the magnetic stripe device comprises a plurality of magnetic stripes which are independent from one another; the magnetic stripes are arranged in the form of a circular array by taking the center of the coil disc as the center of a circle; a magnetic shielding part is arranged at the radial outer side of the magnetic stripe device; and the magnetic shielding part is fixedly arranged on the outer wall of the coil disc. According to the electromagnetic oven disclosed by the invention, the magnetic shielding part is arranged at the radial outer side of the magnetic stripe device, and themagnetic shielding part generates induction current under action of high-frequency magnetic fields, so that electromagnetic leakage of the electromagnetic oven is effectively reduced.

The invention belongs to PVC (polyvinyl chloride) floors and particularly relates to a PVC plastic floor with a conducting layer, which is characterized by comprising the conducting layer, a PVC layer and a composite enhancement layer sequentially from top to bottom; the conducting layer is formed by a film and a wire mesh; the PVC layer contains conductive black; the composite enhancement layer is formed by a non-woven fabrics layer and an adhesive layer; and the film is made of fluorinated ethylene propylene. On the basis of a traditional anti-static PVC plastic floor, the PVC plastic floor provided by the invention also additionally provided with the conducting layer, i.e. the metal mesh, so that the electrical conductivity is greatly enhanced, electromagnetism leakage is prevented, and the PVC plastic floor with the conducting layer is particularly suitable for occasions with high electromagnetism such as nuclear magnetic resonance and the like.