4results about "Mechanically variable capacitors" patented technology

The application relates to the technical field of antenna matching and tuning devices, in particular to a medium wave antenna matching assembly based on double helix inductors, which comprises a shell, a coil set arranged in the shell, a movable magnetic core rod, a lead screw, a variable capacitor, a mounting plate, a coarse tuning knob, a fine tuning knob, an antenna interface and a speed reducer; wherein an operation table is arranged on the shell, the coarse tuning knob and the fine tuning knob are arranged on the operation table; the coil set comprises a first double helix inductor, the magnetic core rod is arranged along the axial direction of the first double helix inductor and can axially move relative to the first double helix inductor; the lead screw is arranged in the shell and is in transmission connection with the magnetic core rod, the coarse tuning knob is in transmission connection with the lead screw so as to drive the magnetic core rod to perform coarse tuning; the variable capacitor is arranged on the mounting plate, the fine tuning knob is in transmission connection with the variable capacitor through the speed reducer so as to perform fine tuning on the variable capacitor; and the antenna interface is arranged on the shell and is electrically connected with the first double helix inductor and the variable capacitor to form an antenna matching network.

With this invention, electronic circuit components such as transistors, diodes, zener diodes and varicap diodes, which are conventionally manufactured with semiconductors, can be produced without semiconductors by means of a much simpler and cheaper technology, and by the same technology a compensation capacitor can be manufactured whose capacitance is automatically varied so as to follow changes in the load simultaneously. This principle may also be applied in other areas such as microwaves. In simple terms, the electric and magnetic fields of the main capacitor are blocked by a control voltage and varied between zero and maximum values, and as a result the capacitance of the main capacitor is changed. The fundamental principle here is the control of the electric and magnetic fields between the two conductive plates of a fixed-capacitance capacitor. For this purpose, a control voltage is applied between a third metallic plate, designed as a grid or similar structure so as not to block the electric and magnetic fields of the main capacitor and placed closer to one of the two plates, and the adjacent metallic plate, while a DC voltage (VDD) of suitable value for the circuit is applied across the terminals of the main capacitor. In a slightly different version, two grids are provided so that the structure can be used both as a diode and as a transistor. In both cases, the capacitance value of the main capacitor varies depending on the control voltage, i.e. Co = f(Vi). This means that, similar to classical transistors, the impedance of the circuit varies depending on the control voltage. In this structure, which exhibits behaviour similar to FET transistors, the output voltage is taken across the two outer plates of the capacitor with a design similar to a classical transistor circuit. In the production stage, the dielectric will be formed by coating very thin special plastic or other suitable materials with an appropriate metal of suitable thickness for the design and winding it in roll form. Likewise, dielectric layers may also be formed as very thin oxide or other non-conductive chemical compounds on the surfaces of the metallic 24 plates. That is, use will be made of conventional capacitor technologies such as ceramic, tantalum and electrolytic capacitors. In addition, different methods may be developed depending on the field of application. These designs will find application areas as semiconductor-free transistors, diodes, voltage-controlled variable capacitors, and many other uses, some of which have been explained in this project.

Ultrasonic Probe This description relates to an ultrasonic probe (200) comprising: - an interconnecting substrate (230); - an array of ultrasonic transducers (201); - a control integrated circuit (202) electrically connected to the array of ultrasonic transducers and positioned on a first face (230A) of the interconnecting substrate; - a capacitive structure (210) positioned on a second face (230B) of the interconnecting substrate opposite the first face, the capacitive structure comprising a mechanically rigid insulating substrate, including at least one dielectric layer, and two metallic elements insulated from each other and positioned on either side of each dielectric layer, forming at least one capacitor. Figure for the abbreviation: Fig. 2A

Provided are a flexible variable capacitor and method for preparation thereof. The flexible variable capacitor includes two highly conductive flexible electrode layers and an elastomer dielectric insulation layer disposed between the two highly conductive flexible electrode layers, wherein the highly conductive flexible electrode layers include first polymeric elastomer and carbon nanomaterial, and the elastomer dielectric insulation layer includes second polymeric elastomer and functional ceramic nanoparticles. The method for preparation of the flexible variable capacitor is as follows: first, preparing an elastomer composite film with different functions, and then pressing upper and lower electrode layers with the intermediate elastomer insulation layer together to obtain a stretchable strip-shaped plate capacitor. Different from existing technologies, the present application uses independently developed highly conductive flexible electrodes to replace traditional silver oil electrodes, which greatly reduces the cost of variable capacitor devices, and enhances the integration and operability. The prepared flexible variable capacitor has characteristics such as high dielectric constant, low dielectric loss, simple preparation process, and capacitance being sensitive to deformation.