An ultrasonic scanning device includes a stator and a rotor pivotably mounted on the stator for oscillation around the axis of rotation. The rotor (or stator) has two elastic bumper stops spaced from the axis of rotation and spaced from each other. An elastic bumper is attached to the stator (or rotor) and arranged between the bumper stops. The resulting scanning device conserves energy by converting kinetic energy in one direction to potential energy, and then by converting the potential energy back into kinetic energy in the opposite direction.

A scanning apparatus and method for scanning an object including a frame, a transducer for obtaining information from an object and a motor oscillating the transducer. The motor comprises a spring/solenoid combination driven at the resonant frequency of the spring/motor system. The actual displacement of the transducer is measured and compared to a desired displacement to provide a control signal to the motor. The scanning apparatus is at least partially enclosed by a housing containing a heat transfer fluid for damping the resonant vibration of the apparatus.

An improved ultrasonic mechanical sector scanning transducer assembly is disclosed. An ultrasonic transducer is disposed for movement within a generally tubular housing. A drive element extends longitudinally within the housing and is coupled for transmitting motion to the transducer. Power means produces oscillatory rotative movement of the drive element and transducer. A diaphragm seal, comprising a resilient tubular membrane, provides a liquid tight seal between longitudinally displaced interior sections of the housing. The tubular membrane has one relatively narrow end and flares along its length to a wider opposite end. The narrow end is bonded about the drive element. The wider end is affixed about the periphery of the housing. A coaxial cable is coupled to the transducer and extends to the exterior of the housing. The cable is wrapped within a spiral groove extending about the outer surface of a spool or reel mounted for movement in unison with the transducer.

An ultrasonic scanning apparatus includes a rotor, first and second electromagnetic stators, and an ultrasonic transducer mounted on the rotor. Each electromagnetic stator has two curved pole faces arranged opposite pole faces on the rotor. The electromagnetic stators are arranged on opposite sides of the axis of rotation of the rotor. The stator pole faces are tapered such that on rotation of the rotor in one direction, the gaps between the rotor and a first stator decrease while the gaps between the rotor and the other stator increase. On rotation of the rotor in the opposite direction, the gaps between the rotor and the first stator increase and the gaps between the rotor and the second stator decrease. Means are provided for alternately energizing the first and second electromagnetic stators to cause the rotor to oscillate about the axis of rotation.

A mechanical ultrasonic scanner includes a transducer element which is swingably supported in a housing, and a sensor for detecting a swinging angle of the transducer element. The sensor includes a permanent magnet swung together with the transducer element, and a magnetoresistive element fixed to the housing to be opposite to a swinging locus of the permanent magnet. The permanent magnet generates a magnetic field between the permanent magnet and the magnetoresistive element. The magnetoresistive element detects a strength of the magnetic field which changes in correspondence with a swinging angle of the magnet, so that the swinging angle of the transducer element is detected on the basis of the change in the strength of the magnetic field. Even if the housing contains a sound transmitting medium, the magnetic field generated by the sensor is not adversely affected by the sound transmitting medium. Therefore, the swinging angle of the transducer element can be accurately detected to accurately obtain a radiating/returning direction of an ultrasonic beam, thus accurately reconstructing an image. In addition, the position of the transducer element can be controlled with high precision.