Transducer with a flexible sensor element for measurement of mechanical values

Claim 1

An apparatus for determining the pressure of a fluid, said apparatus comprising means forming a hollow enclosure in which the fluid whose pressure is to be measured is contained, said means including a wall member which has an edge surface that is configured to provide a cylindrical orifice that communicates with the interior of said hollow enclosure, said edge surface of said wall member including a continuous step portion which extends into said cylindrical orifice and a threaded portion, said step portion being positioned closer to the interior of said hollow enclosure than said threaded portion, a domed membrane which has a diameter that is greater than the diameter defined by the step portion of said wall member, said domed membrane being positioned in said cylindrical orifice such that the periphery thereof is positioned between said step portion and said threaded portion of said wall member and is oriented such that the center thereof is positioned further from the interior of said hollow enclosure than said periphery, a transducer means which has opposite ends and is positioned against the domed membrane on the side thereof facing away from the interior of said hollow enclosure, said transducer means comprising at least one flexible piezoelectric film, at least one flexible piezoelectric film in said transducer means having opposite sides and an electrically conducting surface associated with at least a portion of at least one of the opposite sides thereof, attachment means for stretching said transducer means across said domed membrane and thus across said orifice, said attachment means comprising an annular screw which has a threaded outer surface, said threaded outer surface of said annular screw being engaged with the threaded portion of said wall means such that the annular screw will cause the opposite ends of said transducer means to be clamped and the transducer means to be stretched over said domed membrane.

Claim 2

An apparatus for determining the pressure of a fluid, said apparatus comprising means forming a hollow enclosure in which the fluid whose pressure is to be measured is contained, said means including a wall member which has an edge surface that is configured to provide a cylindrical orifice that communicates with the interior of said hollow enclosure, said edge surface of said wall member including a continuous step portion which extends into said cylindrical orifice and a threaded portion, said step portion being positioned closer to the interior of said hollow enclosure than said threaded portion, a domed membrane which has a diameter that is greater than the diameter defined by the step portion of said wall member, said domed membrane being positioned in said cylindrical orifice such that the periphery thereof is positioned between said step portion and said threaded portion of said wall member and is oriented such that the center thereof is positioned further from the interior of said hollow enclosure than said periphery, a transducer means which has opposite ends and is positioned against the domed membrane on the side thereof facing away from the interior of said hollow enclosure, said transducer means comprising at least one flexible piezoelectric film, at least one flexible piezoelectric film in said transducer means having opposite sides and an electrically conducting surface associated with at least a portion of at least one of the opposite sides thereof, attachment means for stretching said transducer means across said domed membrane and thus across said orifice, said attachment means comprising an annular screw which has a threaded outer surface, said threaded outer surface of said annular screw being engaged with the threaded portion of said wall means such that the annular screw will cause the opposite ends of said transducer means to be clamped and the transducer means to be stretched over said domed membrane.

Claim 5

An apparatus for determining the pressure of a fluid, said apparatus comprising means forming a hollow enclosure in which the fluid whose pressure is to be measured is contained, said means including a wall member which has an edge surface that is configured to provide an orifice that communicates with the interior of said hollow enclosure, said edge surface of said wall member including a continuous step portion which extends into said orifice and a threaded portion, a domed membrane which has a diameter that is greater than the diameter defined by the step portion of said wall member, said domed membrane being positioned in said orifice such that the periphery thereof is positioned between said step portion and said threaded portion of said wall member, a transducer means which has opposite ends and is positioned against the domed membrane, said transducer means comprising at least one flexible piezoelectric film, at least one flexible piezoelectric film in said transducer means having opposite sides and an electrically conducting surface associated with at least a portion of each of the opposite sides thereof, attachment means for stretching said transducer means across said domed membrane and thus across said orifice, said attachment means comprising an annular screw which has a threaded outer surface, said threaded outer surface of said annular screw being engaged with the threaded portion of said wall means such that the annular screw will cause the opposite ends of said transducer means to be clamped and the transducer means to be stretched over said domed membrane.

Claim 6

An apparatus for determining the pressure of a fluid, said apparatus comprising means forming a hollow enclosure in which the fluid whose pressure is to be measured is contained, said means including a wall member which has an edge surface that is configured to provide an orifice that communicates with the interior of said hollow enclosure, said edge surface of said wall member including a continuous step portion which extends into said orifice and a threaded portion, a domed membrane which has a diameter that is greater than the diameter defined by the step portion of said wall member, said domed membrane being positioned in said orifice such that the periphery thereof is positioned between said step portion and said threaded portion of said wall member, a transducer means which has opposite ends and is positioned against the domed membrane, said transducer means comprising at least one flexible piezoelectric film, at least one flexible piezoelectric film in said transducer means having opposite sides and an electrically conducting surface associated with at least a portion of each of the opposite sides thereof, attachment means for stretching said transducer means across said domed membrane and thus across said orifice, said attachment means comprising an annular screw which has a threaded outer surface, said threaded outer surface of said annular screw being engaged with the threaded portion of said wall means such that the annular screw will cause the opposite ends of said transducer means to be clamped and the transducer means to be stretched over said domed membrane.