| 摘要 |
An ultrasonic rotary horn intended to be excited at a frequency of from about 18 to about 60 kHz, which horn is shaped, solid metal object having a radial surface terminated by a first end and a second end, and a rotational axis, in which each of the ends is defined by a surface. The diameter of the horn can vary from about 4 cm to about 19 cm. The width of the horn at the radial surface is in the range of from about 0.6 cm to about 13 cm. The thickness of the horn at its rotational axis is from about 0.6 cm to about 15 cm and is independent of the width of the horn at the radial surface. The horn has a mass in the range of from about 0.06 kg to about 30 kg. The diameter, width, and thickness values are selected for a desired frequency so that the horn, upon being excited by ultrasonic energy at such frequency which is input at the rotational axis at, and substantially perpendicular to, one or both ends, is adapted to resonate in a manner such that: (1) the excited end moves substantially in phase with the movement of the source of excitation; (2) the opposing end, whether or not it is actively excited, moves substantially out of phase with the movement of the excited end; (3) said radial work-contacting surface also moves substantially out of phase with the movement of the excited end; and (4) said horn exhibits a single nodal point at its geometric center. The horn may include hubs on each of the two ends; the hubs being integral parts of the horn; the horn may also include threaded studs which protrude from the ends or from the hubs. The ultrasonic rotary horn of the present invention is particularly useful in continuous processes for bonding together two or more layers of at least partly thermoplastic materials, such as woven and nonwoven fabrics and films. <IMAGE> |
