# US 5,707,483 A · Rotary acoustic horn > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,707,483 A - Document ID: US5707483A - Status: Granted - Kind: A - Application number: 08/676,016 - Filed: 1996-07-05 - Granted: 1998-01-13 - Earliest claimed: 1996-07-05 - Assignees: Minnesota Mining and Manufacturing Company - Inventors: Satinder K. Nayar; Haregoppa S. Gopalakrishna - Web page: https://patentgrep.com/patent/US5707483A ## CPC - B29C 66/83411: {Roller, cylinder or drum types (B29C66/83431 takes precedence; rollers, cylinders or drums moving relative to and tangentially to the parts to be joined B29C66/8362)} - B06B 3/02: involving a change of amplitude - B23K 20/106: {Features related to sonotrodes} - B29C 65/085: {using a rotary sonotrode} - B29C 65/087: {using both a rotary sonotrode and a rotary anvil} - B29C 66/83417: {said rollers, cylinders or drums being hollow} - B29C 66/9512: {by controlling their vibration frequency} - B29C 66/9516: {by controlling their vibration amplitude} - G10K 11/025: {horns for impedance matching (see provisionally also G10K11/28)} - B29C 66/73921: {characterised by the materials of both parts being thermoplastics} - B29C 66/9517: {characterised by specific vibration amplitude values or ranges} - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B06B: METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, {e.g.} FOR PERFORMING MECHANICAL WORK IN GENERAL (for particular applications, see the relevant subclasses, e.g. B07B1/40, B23Q17/12, B24B31/06; measurement of mechanical vibrations G01H; in direction finding, locating, distance or velocity measuring G01S; {generating seismic energy G01V1/02}; control of mechanical vibrations in general G05D; sound-producing devices, e.g. bells, sirens, whistles G10K, {e.g. methods or devices for transmitting, conducting, or directing sound in general G10K11/00}; generation of electrical oscillations H03B; electromechanical resonators in general H03H; electromechanical transducers {for communication techniques, e.g. microphones, speakers} H04R) - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM - G10K: SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR ## Abstract A rotary acoustic horn imparts energy at a selected wavelength, frequency, and amplitude. The horn includes a cylindrical shaft and a cylindrical welding portion mounted on and coaxial with the shaft. The diameter of the welding portion is greater than the diameter of the shaft. The welding portion has a cylindrical weld face having a diameter that expands and contracts with the application of ultrasonic energy, and first and second opposing end portions. At least one end portion is formed with a first undercut; the radial width and the depth of the first undercut is selected to affect the amplitude of vibration at the weld face to provide a desired amplitude profile along the axial length of the weld face. ## Claims ### Claim 1 A rotary acoustic horn for imparting energy at a selected wavelength, frequency, and amplitude, wherein the horn comprises: a shaft having an axial input end and an axial output end; a welding portion mounted on the shaft, and having a diameter that is greater than the diameter of the shaft, wherein the welding portion comprises a weld face having a diameter that expands and contracts with the application of acoustic energy to the input end of the shaft, and first and second opposing end portions, wherein at least one end portion is formed with a first undercut, wherein the first undercut has a width and depth selected to control the amplitude of vibration at the weld face to provide a desired amplitude profile along the axial length of the weld face. ### Claim 2 (depends on 1) The horn of claim 1 wherein the width and the depth of the first undercut are selected to affect the amplitude of vibration at the weld face to provide an amplitude profile that is one of: substantially uniform along the entire axial length of the weld face; greater at the axial ends of the weld face than at the axial center; greater at the axial center of the weld face than at the axial ends; and increasing from one axial end of the weld face to the other axial end, wherein any of the amplitude profiles is attainable. ### Claim 3 (depends on 1) The horn of claim 1 wherein the first undercut has an inner radius that is one of coextensive and non-coextensive with an outer radius of the shaft. ### Claim 4 (depends on 1) The horn of claim 1 further comprising a first undercut formed in the other end portion of the welding portion. ### Claim 5 (depends on 1) The horn of claim 1 further comprising a second undercut in the same end portion as the first undercut. ### Claim 6 (depends on 5) The horn of claim 5 wherein the second undercut is closer to the weld face than the first undercut. ### Claim 7 (depends on 6) The horn of claim 6 wherein the second undercut has a width and depth at least one of which is one of: less than, more than, and equal to the respective depth and width of the first undercut. ### Claim 8 (depends on 1) The horn of claim 1 wherein the axial length of the welding portion can be up to one-half of a wavelength of the horn material. ### Claim 9 (depends on 8) The horn of claim 8 wherein the axial length of the horn is one of (a) substantially equal to one wavelength of the horn material and (b) no more than one-half wavelength of the horn material. ### Claim 10 (depends on 9) The horn of claim 9 wherein the shaft is hollow for at least part of its axial length. ### Claim 11 (depends on 9) The horn of claim 9 wherein the shaft is shorter than one wavelength of the horn material and the welding portion is located so that it extends beyond the end of the shaft to make the entire horn the desired length. ### Claim 12 (depends on 9) The horn of claim 9 further comprising a shaft extension at the output end of the horn. ### Claim 13 (depends on 12) The horn of claim 12 wherein the shaft extension extends beyond the welding portion by a distance of one or more multiples of one-half wavelength of the horn material. ### Claim 14 (depends on 1) The horn of claim 1 wherein the shaft is cylindrical, the welding portion is cylindrical, and the welding portion is coaxial with the shaft. ### Claim 15 (depends on 1) The horn of claim 1 wherein the first undercut is one of continuous and discontinuous around the shaft, and wherein the depth and width of the first undercut each are one of constant and varying. ### Claim 16 (depends on 1) The horn of claim 1 wherein the weld face expansion and contraction moves substantially in phase with the movement of the axial input end of the horn and wherein the horn exhibits two nodal points for axial motion. ### Claim 17 (depends on 1) The horn of claim 1 wherein the weld portion is mounted on and coaxial with the shaft. ### Claim 18 (depends on 1) The horn of claim 1 wherein the weld face expansion and contraction moves substantially out of phase with the movement of the axial input end of the horn and wherein the horn exhibits one nodal point for axial motion. ### Claim 19 (depends on 1) The horn of claim 1 which is an ultrasonic horn. ### Claim 20 (depends on 1) The horn of claim 1 further comprising means for changing the gain at the radial weld face by changing the mass at the axial input end of the horn. ### Claim 21 (depends on 1) The horn of claim 1 comprising a plurality of coaxial welding portions mounted on the shaft, wherein the welding portions are spaced from each other, and wherein the welding portions are mounted in one of series and parallel with each other. ### Claim 22 (depends on 21) The horn of claim 21 wherein the distance between midpoints of adjacent welding portions is at least one multiple of one-half wavelength of the horn material. ### Claim 23 (depends on 21) The horn of claim 21 wherein the amplitude of vibration of each welding portion differs from the amplitude of vibration of adjacent welding portions.