초록 ▼

An ultrasonic apparatus for measuring the speed of sound in a gaseous medium comprises a chamber in which an ultrasonic transducer is mounted at one end of the chamber and first and second ultrasonic reflecting surface are mounted at the opposite end of the chamber with a temperature insensitive mou

An ultrasonic apparatus for measuring the speed of sound in a gaseous medium comprises a chamber in which an ultrasonic transducer is mounted at one end of the chamber and first and second ultrasonic reflecting surface are mounted at the opposite end of the chamber with a temperature insensitive mounting member for mounting the second ultrasonic reflecting surface at a predetermined distance closer to the ultrasonic transducer than the first ultrasonic reflecting surface and a circuit connected to the transducer for converting ultrasonic energy reflections from the first and second reflecting surfaces to a signal corresponding to the speed of the ultrasonic energy between the two ultrasonic reflecting surfaces. Thus, the distance from the transducer to the targets is not relevent - only the distance between the two reflectors which is established by the temperature insensitive mounting member is relevant. In a preferred embodiment, the ultrasonic reflecting surfaces are concentric and coaxial and, the chamber includes a cylindrical cylinder which has a diameter larger than the most remote of the two reflecting surfaces and an annular groove is formed beyond the second reflecting surface.

대표청구항 ▼

Ultrasonic apparatus for measuring the speed of sound in a gaseous medium, comprising: (1) a closed chamber having a first end and an opposing end, (2) an ultrasonic transducer mounted at said first end of said closed chamber, (3) a first ultrasonic reflecting surface mounted at said opposing end of

Ultrasonic apparatus for measuring the speed of sound in a gaseous medium, comprising: (1) a closed chamber having a first end and an opposing end, (2) an ultrasonic transducer mounted at said first end of said closed chamber, (3) a first ultrasonic reflecting surface mounted at said opposing end of said closed chamber, (4) a second ultrasonic reflecting surface, (5) a mounting member having a low coefficient of linear expansion for mounting said second ultrasonic reflecting surface at a predetermined distance spaced from said first ultrasonic reflecting surface and closer to said ultrasonic transducer, and (6) circuit means connected to said transducer for converting ultrasonic energy reflections from said first and said second ultrasonic reflecting surfaces to a signal corresponding to the speed of ultrasonic energy in said gaseous medium between said ultrasonic reflecting surfaces.