Abstract: A method for closing an open end of a thermoplastic tube by applying ultrasonic energy to the end in a direction normal to the longitudinal axis of the tube. A horn adapted to undergo ultrasonic vibrations is provided and includes an open cavity disposed substantially at an antinodal region of longitudinal motion of the horn and oriented normal to the direction of longitudinal motion of the horn. The horn is rendered resonant along its longitudinal axis while the open end concomitantly is urged into the cavity in a direction normal to the direction of longitudinal motion of the horn thereby forming the end to the shape of the cavity.

Abstract: A method for securing a thermoplastic part to another part by applying ultrasonic energy to a projection of the thermoplastic part in a direction substantially normal to the longitudinal axis of the projection. The exposed end of the projection is urged into an open cavity disposed in a side wall of a horn adapted to undergo ultrasonic vibrations. The cavity further is disposed substantially at an antinodal region of longitudinal motion of the horn and oriented normal to the direction of longitudinal motion of the horn. The horn is rendered resonant along its longitudinal axis while the exposed end concomitantly is urged into the cavity.

Abstract: A corner is formed in corrugated thermoplastic material or board using ultrasonic vibrations by disposing the corrugated material between an anvil and a half wavelength resonator having a portion of its frontal surface shaped for producing a crease. Contact is provided between the shaped portion of the resonator frontal surface and the material so as to crush the material. The resonator is rendered resonant for causing the material in contact with the resonator frontal surface to soften and flow. After a sufficient period of time, usually a fraction of a second, the frontal surface is withdrawn from contact with the material. When the softened and flowing material solidifies a crease is manifest in the material which then is folded to form a corner.

Abstract: The invention refers to a method of joining two non-fusible workpieces using frictional energy. A first workpiece having a higher melting temperature is provided with a recess extending from the mating surface of the workpiece into the interior thereof. The recess is shaped for trapping material. A static force applied in a direction normal to the mating surfaces of the workpieces to be joined urges the first workpiece into intimate contact with a second workpiece having a lower melting temperature. The workpieces are subjected to relative motion in the plane of the mating surface for causing frictional energy and a softening of the second workpiece. The softened material flows into the recess and solidifies upon cessation of the relative motion. The workpieces are thus joined by virtue of the solidified material trapped in the recess.

Abstract: A storage battery comprising a thermoplastic cover having a hollow metallic terminal therein and a thermoplastic case having an upstanding metallic core member passing through the terminal is assembled using vibratory energy. The cover and the case undergo relative reciprocating translating motion while under the influence of a static force applied in a direction perpendicular to the plane of the mating surfaces between the cover and case. The terminal and core are dimensioned for providing a peripheral clearance around the core in the direction of the reciprocating motion at least equal to the peak-to-peak displacement of the vibratory motion. The gap existing between the core and the terminal when the battery is assembled is sealed.