초록 ▼

A method and apparatus for casting molten metal in an opaque container and for determining the level of the metal within the container. This is accomplished by locating a strain sensing transducer over the container and metal, and sending a current pulse from the transducer along a wire located in t

A method and apparatus for casting molten metal in an opaque container and for determining the level of the metal within the container. This is accomplished by locating a strain sensing transducer over the container and metal, and sending a current pulse from the transducer along a wire located in the tube connected to the transducer and extending toward the vessel and molten metal. A permanent magnet is located on a stem connected to a float within the container, the float being effective to rest and float on the upper level of the molten metal within the container. A current pulse is sent along the wire from the transducer, which pulse produces a magnetic field, and which field interacts with a magnetic field of the permanent magnet. The interaction of the two fields exerts a strain on the tube, which strain is sensed by the transducer. The transducer also notes the time at which the current pulse is sent along the wire and produces and output signal indicative the time elapsed between the sending of the current pulse and the sensing of the strain on the tube. The elapsed time being proportional to the level of molten metal within the opaque container.

대표청구항 ▼

Apparatus for sensing the level of molten metal in a container, comprising: an electrical, strain sensing, pulse producing and output signal producing transducer located above the molten metal and external of the container, a structure for supporting said transducer above the molten metal and contai

Apparatus for sensing the level of molten metal in a container, comprising: an electrical, strain sensing, pulse producing and output signal producing transducer located above the molten metal and external of the container, a structure for supporting said transducer above the molten metal and container, a first tube connected to and extending downwardly from the transducer toward the molten metal, a magnet located adjacent said first tube and at a location spaced from both the transducer and molten metal, said magnet providing a magnetic field, a second, vertically moveable tube located beneath said first tube and attached to said magnet, float means connected to a lower end of said second tube for floating on the surface of the molten metal and for vertically moving the magnet, said float means being made from a heat resistant material, and a wire located in said first tube and electrically connected to the transducer, the wire, in addition, extending to a location adjacent the magnet, said transducer being capable of sending a pulse of current down the wire, which pulse creates a magnetic field that travels with the current pulse and interacts with the field of the magnet in a manner that strains the first tube, and said transducer sensing said strain and producing said output signal proportional to the time between the sending of the pulse and the sensing of the strain, said output signal varying with the level of molten metal in the container.