539results about "Mechanically variable capacitors" patented technology

A capacitive proximity switch for detecting the change in the capacitance relative to a setpoint capacitance by the approach or retreat of an object in the sensitive area of a proximity switch, especially for use in the door handle of a motor vehicle, provides reliable error detection and error suppression at a fundamentally high sensitivity of the capacitive proximity switch by utilizing an evaluation unit that evaluates a measured value of the change in capacitance over time and depending on the time behavior of the measured value activates changes the operating threshold from a first threshold (which can be caused by a false object coming into or out of the sensitive area of the proximity switch) to a higher second threshold which can be reached only at a relatively greater change in capacitance caused by a target object coming into or out of the sensitive area of the proximity switch.

An anode (14, 208, 410) and / or cathode (12, 212, 420) of a capacitor has a large surface area. The high surface area of the anode is provided by forming the anode from a thin, electrically conductive layer (16) formed from metal particles (18) or an electrically conductive metallic sponge (416). These materials provide a porous structure with a large surface area of high accessibility. The particles are preferably directional or non-directional sponge particles of a metal, such as titanium. The conductive layer has a dielectric film (36, 236, 414) on its surface, formed by anodizing the particle surfaces. The dielectric film has a combination of high dielectric constant and high dielectric strength. The cathode (12, 212, 420) of the capacitor is either a conventional solid material or, more preferably, has a large surface provided by forming the surface from a sponge or particles analogously to the anode. The high dielectric strengths obtainable from the capacitor allow for extreme miniaturization, making the capacitor particularly suited for integrated circuit applications.

Disclosed herein is a structural sheet includes an energy storage density that is greater than 10-mWh / ft2 and is capable of withstanding greater than 5-KPa stress under at least 5% strain.

A solid electrolytic capacitor comprising a capacitor element obtainable by compressing a porous valve-acting metal substrate having on the dielectric film surface thereof a solid electrolyte layer containing an electrically conducting polymer in the thickness direction, wherein assuming that the maximum thickness and the minimum thickness of the electrically conducting polymer layer including the substrate before the compression are Hamax and Hamin, and the maximum thickness and the minimum thickness of the electrically conducting polymer layer after the compression are Hbmax and Hbmin, the percentage decrease ΔH in the difference of thickness represented by the following formula is preferably from 5 to 95%: Formula (I). The thin solid electrolytic capacitor element of the present invention, which can be stably produced with a small variety in shape, enables fabrication of a solid electrolytic multilayer capacitor having a high-capacitance and small-size with a low height, which, free from short-circuit failure, exhibits stable performanceΔ⁢⁢H⁡(%)=[1-(Hb⁢⁢max-Hb⁢⁢min)(Ha⁢⁢max-Ha⁢⁢min)]×100.(I)

A method for increasing the surface area of foil electrodes of electrolytic capacitors. A valve metal is deposited by evaporation on a valve metal foil in a low pressure inert atmosphere including oxygen at a pressure one to two orders of magnitude lower than the pressure of the inert gas. The resulting surface is fractal-like. The foil thus treated is suitable as such for use as a cathode. Prior to anodization to produce an anode, a discontinuous layer of a valve metal oxide is deposited on the foil, to preserve the high surface area of the fractal-like surface and otherwise promote the formation of a dielectric coating whose interface with the metal foil has a high surface area.