Abstract: The present disclosure relates to an apparatus for determining and/or monitoring a process variable of a medium in a containment, including an oscillatable unit with a membrane, three rods secured to the membrane and extending perpendicularly to a base area of the membrane, a housing, wherein the rods extend into the housing a driving/receiving unit disposed at an end region of the rods and configured to excite the oscillatable unit and transduce mechanical oscillations into a received signal, and an electronics unit configured to produce an exciter signal from the received signal and to ascertain the process variable at least from the received signal. At least one of the rods is secured to the membrane at a site on the base area where the second derivative of the deflection of the membrane from a rest position as a function of the site on the base area is essentially zero.

Abstract: An electromechanical transducer unit for a field device includes a membrane embodied to execute mechanical oscillations, two rods perpendicular to the membrane and secured to the membrane, a housing, wherein the membrane forms at least one portion of a wall of the housing, and wherein the two rods extend into the housing interior, two magnets, wherein each magnet is secured in an end region away from the membrane to a different one of the two rods, and a coil with a core, wherein the coil is secured above the magnets within the housing, and is contactable with an electrical, alternating current signal, wherein the coil is embodied to produce a magnetic field that causes the two rods via the two magnets to execute mechanical oscillations, and wherein the two rods are secured to the membrane such that oscillations of the membrane result from oscillations of the two rods.

Abstract: The present invention relates to a vibronic sensor for determining a process variable of a medium in a containment, comprising a mechanically oscillatable unit, a driving/receiving unit and an electronics unit having an adaptive filter. The present invention relates also to a method for operating the sensor. The electronics unit is embodied alternately to execute a first operating mode and a second operating mode. The driving/receiving unit is embodied during the first operating mode to excite the oscillatable unit using an electrical excitation signal. During the second operating mode, the exciting of the oscillatable unit is interrupted and the oscillations of the oscillatable unit are received and transduced into an electrical, received signal. At least one filter characteristic of the adaptive filter is set such that a predeterminable phase shift is present between the excitation signal and the received signal, and the process variable is determined from the received signal.

Abstract: The present disclosure relates to an apparatus for determining and/or monitoring a process variable of a medium in a containment, including an oscillatable unit with a membrane, three rods secured to the membrane and extending perpendicularly to a base area of the membrane, a housing, wherein the rods extend into the housing a driving/receiving unit disposed at an end region of the rods and configured to excite the oscillatable unit and transduce mechanical oscillations into a received signal, and an electronics unit configured to produce an exciter signal from the received signal and to ascertain the process variable at least from the received signal. At least one of the rods is secured to the membrane at a site on the base area where the second derivative of the deflection of the membrane from a rest position as a function of the site on the base area is essentially zero.

Abstract: The present disclosure includes an electromechanical transducer unit for a field device of automation technology including a membrane having a base area and displaceable to execute mechanical oscillations, three rods secured to the membrane perpendicular to the base area, a housing, wherein the rods extend into the housing, three magnets, each secured to one of the rods opposite the membrane, and a coil having a core and secured within the housing adjacent the magnets, the coil embodied to produce a magnetic field that causes the rods to execute mechanical oscillations. The rods are secured to the membrane such that oscillations of the membrane result from the oscillations of the rods. At least one of the rods is secured to the base area where the second derivative of the deflection of the membrane from a rest position as a function of the site on the base area is essentially zero.

Abstract: An electromechanical transducer unit for a field device comprising a membrane embodied to execute mechanical oscillations, two rods perpendicular to the membrane and secured to the membrane, a housing, wherein the membrane forms at least one portion of a wall of the housing, and wherein the two rods extend into the housing interior, two magnets, wherein each magnet is secured in an end region away from the membrane to a different one of the two rods, and a coil with a core, wherein the coil is secured above the magnets within the housing, and is contactable with an electrical, alternating current signal, wherein the coil is embodied to produce a magnetic field that causes the two rods via the two magnets to execute mechanical oscillations, and wherein the two rods are secured to the membrane such that oscillations of the membrane result from oscillations of the two rods.

Abstract: A vibronic sensor for monitoring a process variable of a medium in a containment, comprising a mechanically oscillatable unit, a driving/receiving unit and an electronics unit. The mechanically oscillatable unit has two oscillatory rods and a tuning element of variable stiffness mechanically connected with at least one of the oscillatory rods. At least a first, outer, oscillatory rod is tubular and surrounds a second, inner, oscillatory rod coaxially, wherein each of the two oscillatory rods is secured in such a manner on a shared carrier that each oscillatory rod can execute oscillations transversely to its longitudinal direction.

Abstract: An apparatus for determining and/or monitoring at least one process variable of a medium in a container, comprising at least an oscillatable unit having at least one membrane, and at least one oscillatory element, a driving/receiving unit embodied to excite the mechanically oscillatable unit by means of an electrical, exciter signal of adjustable excitation frequency to execute oscillations in an oscillation mode corresponding to the excitation frequency and to receive mechanical oscillations from the oscillatable unit and to convert such into an electrical received signal, and an electronics unit embodied, to produce the exciter signal, and to ascertain from the received signal the at least one process variable. The membrane is connected with the driving/receiving unit. The oscillatory element has the shape of an oscillatory rod, on which a paddle is terminally formed, and the oscillatory element is secured on the membrane in an end region remote from the paddle.

Abstract: A vibration sensor comprising an oscillatable unit, which is composed of a membrane with an inner surface and an outer surface and, in given cases, at least one oscillatory element secured on the outer surface of the membrane. A transmitting/receiving unit is provided, which with a predetermined exciter frequency excites the oscillatable unit to execute oscillations and which receives oscillations of the oscillatable unit. A control/evaluation unit is provided, which signals reaching of the predetermined fill level or ascertains the density, respectively the viscosity, of the medium. In order to be able to apply the vibration sensor in high temperature applications, a disc shaped element of a magnetostrictive material is provided, which has a force transmitting connection with the inner surface of the membrane. The transmitting/receiving unit is an electromagnetic drive.