Abstract: In an angular velocity sensor, an acceleration sensor is arranged on a resonator formed of a multilayer substrate and attached to a resonating bar. The multilayer substrate includes a top silicon layer, an insulating sacrificial layer arranged below the top silicon layer, and a bottom silicon layer arranged below the insulating sacrificial layer. An excitor causes the resonator to vibrate while a limit stop, configured out of the multilayer substrate, limits the movement of the resonator.

Abstract: An RPM sensor for anti-lock and/or traction control systems of motor vehicles or for engine speed governing or gasoline or Diesel injection control. The RPM sensor has a housing, receiving electrical components, with a first housing part of plastic that is at least partly enveloped by a second housing part, produced in an injection molding process, likewise from plastic. To attain a moisture-proof, material bond between the two housing parts, a melting element of a plastic having a lower melting point than that of the plastic of the housing parts is disposed in a contact zone between the two housing parts. When the second housing part is formed, the melting element is heated above its melting point, and a material bond of the two housing parts is attained which protects the RPM sensor against moisture dirt, stress, etc.