PRESSURE SENSOR AND MANUFACTURE THEREOF

PURPOSE:To detect pressure conveniently by detecting the conduction between flexible electrodes provided on both sides of an insulation rubber sheet with the deformation of one thereof under a specified external pressure after conductive fine wires are arranged side by side along the thickness of the rubber sheet with the length thereof shorter than the thickness thereof. CONSTITUTION:A magnetic stainless steel fibers are cut off to make a number of short fibers with a fixed length. The short fibers thus obtained are mixed into a low temperature hardening type silicon rubber liquid, the mixture is sandwiched between two polyester sheets at the thickness slightly larger than the length of the short fibers with a spacer placed and then, a magnetic field is applied to orient the short fibers thicknesswise being held between glass plates. In this manner, a pressure-sensitive conductive rubber sheet 4 is formed. The sheet 4 thus obtained is placed between a back conductor 1 having a conductor 3 laminated on an insulation substrate 2 and a flexible conductor 5 adapted to press it 4 with a detection pressure through a spacer 6 and mounted in case 7 and 8. With such an arrangement, when the conductor 5 receives a certain external pressure, an electric flow takes place between the conductors 3 and 5.