Rigid isolation of rotary ultrasonic horn

IS 2 395 019 Τ3

DESCRIPTION

Rigid isolation of a rotating horn

TECHNICAL SECTOR OF THE INVENTION

The present invention relates generally to a method and apparatus that can be used in ultrasonic treatment operations. As particular features, the method and apparatus may include a rotating sonotrode, and the ultrasonic treatment may include an ultrasonic bonding operation. More particularly, the invention relates to an ultrasonic treatment method and apparatus that can provide operational rotary horn isolation using a connection system having relatively high stiffness and toughness.

BACKGROUND OF THE INVENTION

Conventional ultrasonic systems have been including a rotating sonotrode that collaborates with a rotating anvil. Such a system is disclosed in US-A-5,976,316. Conventional rotating ultrasonic horns have been supported and mounted using rubber or other elastomeric components to provide ultrasonic isolation. As a result, the ultrasonic sonotrode exhibits low static toughness, low dynamic toughness, and exhibits excessively large amounts of off-center or other displacement during ordinary operation. Additionally, conventional ultrasonic sonotrode systems have been employing complicated and unreliable torque transmission techniques.

To help address the various drawbacks, conventional ultrasonic bonding systems have been employing additional support wheels to help hold the ultrasonic sonotrode in the desired position relative to the rotating anvil cooperating with the sonotrode. Typically, the support wheels have been configured to hold the rotating horn in direct, substantially continuous contact with the rotating anvil during ordinary operation. However, the use of such support wheels excessively increases the audible noise of the system and causes excessive wear on the ultrasonic horn work surface. Additionally, the sonotrode exhibits uneven wear or requires the use of an oscillating mechanism to distribute the wear more evenly. The torque transmission systems required for rotary horn drive are excessively expensive, require excessive maintenance, and are difficult to set up and adjust. Conventional ultrasonic horn systems also create areas on the horn work surface that are inadequate to perform the desired joining operations and do not provide sufficient levels of dynamic stability. Additionally, conventional ultrasonic sonotrode systems require excessively critical adjustments and are excessively complex and costly. When rubber or other elastic materials are used to provide sound insulating mounts, such mounts can generate excessive reflected energy if the elastomeric material is too compressed. As a result, there is a continuing need for an improvement in ultrasonic bonding systems.

BRIEF DESCRIPTION OF THE INVENTION

The ultrasonic treatment method and apparatus of the invention include an element of a rotating ultrasonic sonotrode operatively attached to an isolation element. In a particular aspect, the insulating element can have a high stiffness. The isolation element is configured to operatively bend under a range of sonic frequencies activated by the sonotrode to provide an operative component of motion along a radial direction and an operative component of motion along an axial direction.

The isolation element has a radial isolation component and an axial isolation component. The radial isolation component is operatively attached to the shaft member, and is configured to extend, at least radially, from the shaft member. The radial isolation component is configured to operably bend under the range of sonic frequencies activated by the sonotrode. The axial isolation component is operatively attached to an operative part of the radial isolation component and is configured to extend, at least axially, from the radial isolation component. The axial isolation component is configured to operably bend under the range of sonic frequencies activated by the sonotrode.

The invention provides a characteristic rotary ultrasonic sonotrode system including a corresponding waveguide and at least one isolating element having high rigidity and toughness. The isolation member can operatively isolate radial movement that may originate at the longitudinal node of a waveguide, and can provide a sufficient bandwidth to compensate for nodal displacements that may occur during ordinary operation. The insulating element can also provide better toughness to reduce deformations under load. The increase in

ES 2 395 019 Τ3 toughness can help maintain concentricity and help reduce off-center offsets. Additionally, the isolation element can transmit torque more efficiently and can provide improved effectiveness and efficiency. The isolation member can also be configured to reduce stress concentrations and increase fatigue resistance, and can provide a mounting system that can reduce relative movements between component parts. The method and apparatus of the invention can reduce the need for elastomeric isolation components and can eliminate the need for conventional elastomeric O-rings and associated isolation ring equipment. The method and apparatus can also reduce the need for keys for torque transmission and can avoid the use of auxiliary support wheels to maintain the desired rotary horn and rotary anvil positions.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood and additional advantages will be apparent upon reference to the following detailed description of the invention and the drawings, in which:

Figure 1 shows a schematic, side view of an exemplary method and apparatus that may incorporate the present invention;

Figure 2 shows a schematic, front view of an exemplary method and apparatus that may incorporate the present invention;

Figure 3 shows a representative perspective view of a representative element of a sonotrode and an isolation element that can be used with the method and apparatus of the invention;

Figure 4 shows a schematic view of a cross section, in a rotatably mounted configuration of the sonotrode element and the isolation element shown in Figure 3;

Figure 5 shows a representative perspective view of another horn element and isolation element that can be used with the method and apparatus of the invention;

Figure 6 shows a schematic cross-sectional view, in a rotatably mounted configuration of the sonotrode element and the isolation element shown in Figure 5;

Figure 6A shows a schematic cross-sectional view in an arrangement in which the sonotrode element and the isolation element are rotatably mounted with a series of support bearings;

Figure 7 shows a schematic side view of a representative sonotrode element and isolation element mounted with associated components on a substantially inelastic bearing;

Figure 8 shows a schematic view of a cross section through the mounted horn member and isolation member shown in Figure 7;

Figure 9 shows a representative perspective view of a sonotrode element and an isolation element that can be mounted with a pair of rigid, substantially non-elastic support bearings;

Figure 10 shows a schematic cross-sectional view of a configuration of a sonotrode element and an isolation element, in which the isolation element has an axial isolation component that is arranged separate from the radial isolation component, and the axial isolation component is integrally formed with an associated coupling device;

Fig. 10A shows a schematic cross-sectional view of another configuration of a sonotrode element and an isolation element, in which the isolation element has an axial isolation component that is disposed spaced from the radial isolation component, and the axial isolation component is integrally formed with an associated coupling device;

Figure 10B shows a schematic cross-sectional view of a configuration of a horn element and an isolation element in which the isolation element has an axial isolation component that is integrally disposed with the radial isolation component, and the isolation element is integrally formed with an associated coupling device;

Figure 10C shows a schematic cross-sectional view of a configuration of a sonotrode element and an isolation element, in which a coupling device is snapped into the axial isolation component of the isolation element.

IS 2 395 019 Τ3

DETAILED DESCRIPTION OF THE INVENTION

The method and apparatus incorporating the present invention can be used with any operational ultrasonic treatment operation. Representative examples of such processing operations may include ultrasonic cutting, punching, joining, welding, drawing, stapling, heat activation, or the like, as well as combinations thereof.

In the present invention, the terms "bonding" and "welding" can be used interchangeably and refer to substantially permanently bonding at least one layer of a material with another layer of a similar or different material. The nature of the materials to be joined is not considered to be critical. However, the present invention is particularly useful in bonding two or more layers of materials such as woven fabrics, nonwovens, and films.

The term "fabric" is used in the present invention in a broad sense to refer to a sheet or web of a fibrous, woven or non-woven material. The fabric or film layer may be continuous, such as on a roll, or it may be discontinuous.

Materials ultrasonically treated by the method and apparatus can include thermoplastic polymers or other thermoplastic materials. Alternatively, the treated materials may not include a thermoplastic material.

Representative method and apparatus configurations will be disclosed and described with reference to, for example, an ultrasonic bonding operation. It is clear that a suitable joint or welding can be achieved by a variety of mechanisms. For example, the bond may be the result of partial or complete fusion in the bond zone of all the materials to be bonded. In this case, there is a partial or complete fusion of said materials in the bonding zone of said materials. Alternatively, the joint can be the result of the partial or complete fusion of one of the materials to be joined, the partially or completely molten material flowing into or over the adjacent materials, which in turn produces a mechanical immobilization of a material. with the other.

The present invention will be expressed in terms of its various components, elements, constructive forms, configurations and arrangements that can also be individually or collectively referenced by the terms "aspect / s" of the invention, characteristic / s of the invention or other similar terms. .

It should also be noted that when used in the present invention, the terms "" comprise "," comprising "and other derivatives of the root term" comprise "are intended to be open terms that specify the presence of any characteristics, indicated elements, integers, stages or components, and are not intended to preclude the presence or addition of one or more other characteristics, elements, integers, stages, components or groups thereof.

The technology of the invention can be configured to produce various types of desired articles. Such items can be, for example, suits, covers, coats, curtains, garments, packaging or the like. The articles can also be absorbent articles, and the absorbent articles can include infant diapers, children's sweatpants, feminine hygiene articles, adult incontinence garments, and the like. The articles can be disposable and intended for limited use. Typically, it is not intended that disposable items can be washed and reused.

With reference to Figures 1 and 2, the process and apparatus of the invention may have a certain length in the machine direction -24- extending longitudinally, a lateral transverse direction -26- extending longitudinally. transverse, and a direction on the z axis. For the purposes of the present invention, the machine direction -24- is the direction along which a particular component or material is transported in the sense of length along and through a particular local position, of the apparatus and of the method. The transverse direction -26- is generally located in the plane of the material being conveyed in the process, and is aligned perpendicular to the local direction -24- of the machine. The z-direction is aligned substantially perpendicular to both the machine direction -24- and the transverse direction -26-, and extends generally along the thickness dimension in the depth direction.

Referring to Figures 1, 2 and 5, the various components used in the method and apparatus may have an axial direction -100-, a radial direction -102- and a circumferential direction -104-. The axial direction 100 extends along a designated axis of rotation of a selected component or element. The radial direction 102 extends radially from the axis of rotation and is substantially perpendicular to the axis of rotation of the selected component or element. The circumferential direction -104- is directed in an orbital path around the axis of rotation of the selected component or element, and is aligned substantially perpendicular to the radial direction -102- and is substantially perpendicular to the axial direction -100-.

IS 2 395 019 Τ3

As shown in Figures 1 and 2, a representative method and apparatus -20- for ultrasound treatment of a target material -98- may include an element -28- of an ultrasonic sonotrode and an element -86- of an associated ultrasonic rotary anvil. In a particular configuration, the method and apparatus may be arranged to provide a bonding operation. The rotating element 86 of the anvil may be associated, proximal to the sonotrode element 28, and an ultrasonic power source or piezoelectric converter 82 may be operatively connected to the sonotrode element. Typically, the sonotrode member and the anvil member may be configured to rotate in the opposite direction with respect to each other, and provide a nip between them where the bonding operation can be carried out. A suitable sonotrode drive 92 may be configured to rotate the sonotrode member, and a suitable anvil drive 94 may be configured to rotate the anvil member. The sonotrode drive and the anvil drive can be provided with individual drive mechanisms, arranged separately, or they can be provided with the same drive mechanism. In a particular arrangement, the sonotrode element can rotate by means of the selected actuation mechanism, and the anvil element can be actuated by a pressure contact that is generated in the area of ​​the constriction between the sonotrode element -28-, the target material -98- to work and the element -86- of the anvil. Suitable drive systems may include power drive shaft taps, motors, combustion engines, electric motors, or the like, as well as combinations thereof.

The rotating element -86- of the anvil has an axis of rotation -114- and can rotate by means of its corresponding rotation drive -94- to provide a minimum speed of the anvil on its outer peripheral surface -90-. In a particular aspect, the peripheral speed of the anvil can be at least a minimum of about 5 m / min. Alternatively, the peripheral speed of the anvil can be at least about 7m / min and optionally can be at least about 9m / min to provide improved performance. In another aspect, the peripheral speed of the anvil can be up to a maximum of about 700 m / min or higher. The peripheral speed of the anvil can alternatively be up to about 600 m / min and optionally can be up to about 550 m / min to provide improved effectiveness. The speed of the anvil can be substantially constant or it can be non-constant or variable, as desired.

As shown by way of example, the anvil element 86 may be disc-shaped, substantially circular, and the peripheral outer surface 90 of the anvil element may be substantially continuous. Alternatively, the anvil element may have a non-circular shape. Additionally, the outer peripheral surface of the anvil element can be discontinuous. Optionally, the anvil element can have a shape composed of one or more spokes or lobe elements, and the spokes or lobe elements can have the same size and / or shape or they can have different sizes and / or shapes.

The sonotrode element -28- has an axis of rotation -112- and can be rotated by its corresponding rotational drive -92- to provide a sonotrode speed at its outer peripheral surface -88 that substantially equals the peripheral speed of the anvil. Optionally, the peripheral speed of the sonotrode element 28 may be unadjusted and not equal to the peripheral speed of the anvil element 86.

As shown by way of example, the sonotrode element 28 may have a substantially circular disc shape and the peripheral outer surface 88 of the sonotrode element may be substantially continuous. Optionally, the horn element can have a non-circular shape. Additionally, the outer peripheral surface of the horn element may have a discontinuous configuration.

An ultrasonic piezoelectric converter 82 may be operatively connected to direct a sufficient amount of ultrasonic power to the sonotrode element 28 through suitable ultrasonic waveguides, intensifier elements, and connecting / transmitting components. Suitable ultrasonic piezoelectric converters, ultrasonic connectors, ultrasonic intensifiers, and ultrasonic waveguides are well known in the art and are available from commercial vendors.

Referring to Figures 3 through 9, the method and apparatus 20 for bonding or other treatment may include a rotating sonotrode ultrasonic element 28 and a rotating shaft element 34. The sonotrode element can have a first axial side -30- and a second axial side -32-. The shaft element may be operatively connected to the sonotrode element 28, and an isolation element 42 can be operatively connected to the sonotrode element 28. In a particular aspect, the isolation element -42- is capable of dynamically flexing and curving under a range of sonic frequencies activated by the sonotrode to provide an operational component of movement along a radial direction -102- of the isolation element. , and can provide an operating component of movement along a radial direction -100 of the isolation element.

In other aspects, the shaft element 34 may provide a plane 38 of the node, and the isolation element 42 may be operatively located close to the plane of the shaft element node. As illustrated in the configuration shown by way of example, the shaft element 34 can be configured to provide a

ES 2 395 019 Τ3 operational waveguide capable of directing ultrasonic energy from a suitable source of ultrasonic power to the sonotrode element.

In particular configurations, the shaft element 34 may provide a plane of the node and / or a plane of the antinode. The isolation element 42 may be located substantially in the corresponding plane of the node or approximately adjacent to it; it may be located substantially in or approximately adjacent to the corresponding plane of the antinode; or it may be located in a position that is separate from its corresponding plane of the node or from the plane of the antinode; as desired.

In additional aspects, the insulation member 42 may have high stiffness and toughness, and may be substantially non-elastomeric. The dynamic bending of the insulation element can be substantially non-elastomeric and can be provided by a mechanism that is substantially free of a component made of an elastomer; such as natural or synthetic rubber. In still other aspects, the insulation member may provide a generally cantilevered flex and curvature. Additionally, the isolating element may provide a bending or flexural displacement operating component that is directed transversely to the radial direction of the isolating element, and may provide a bending or flexural displacement operating component that is directed transversely to the axial direction of the insulating element.

In yet another aspect, the isolation member -42- may have a radial isolation component -46- and an axial isolation component -50-. Radial isolation component 46 may be operatively attached to shaft member 34 and may be configured to extend, at least substantially radially, from shaft member 34. In a particular aspect, the radial insulation component may extend from the shaft member in a generally cantilevered configuration. The radial isolation component 46 may be configured to operatively flex and bend under the range of sonic frequencies activated by the sonotrode. Additionally, the radial insulation component can be dynamically bent to provide transverse displacements that are directed along the thickness dimension of the radial insulation component. Consequently, the dynamic curvature of the radial insulation component can generally oscillate along the axial direction of the insulation element.

The axial isolation component 50 may be operatively attached to an operative portion of the radial isolation component 46 and may be configured to extend, at least axially, from the radial isolation component 46. In a particular aspect, the axial isolation component may extend from the radial isolation component in a generally cantilevered configuration. The axial isolation component 50 may be configured to operatively flex and bend under the range of sonic frequencies activated by the sonotrode. Additionally, the axial isolation component can be dynamically bent to provide transverse displacements that are directed along the thickness dimension of the axial isolation component. Consequently, the dynamic curvature of the axial insulation component can generally oscillate along the radial direction of the insulation element.

The various aspects, features, and configurations of the method and apparatus, taken alone or in combination, can provide a unique rotary ultrasonic horn system that includes a corresponding waveguide, such as that provided by y-axis element 34. at least one insulating element -42 having high rigidity and toughness. The isolation element can operatively isolate radial movement that may occur at the longitudinal node of the waveguide, and it can provide sufficient bandwidth to compensate for nodal displacements that may occur during ordinary operation. In particular, the isolation element can compensate for changes in the real-time position of the real nodal plane that occur during the actual transfer of ultrasonic energy through the waveguide. The insulating element can also provide a toughness improvement to reduce deformations under load. The improvement in toughness can help to maintain concentricity and reduce displacement due to off-centering at the working surface of the sonotrode element. Furthermore, the isolation element can more efficiently transmit the torque to the horn element and can provide improved operational effectiveness and efficiency. The isolation member can also be configured to reduce stress concentrations and increase fatigue resistance. Additionally, the isolation element can provide a mounting system that can reduce relative movements between component parts. The method and apparatus can eliminate the need for elastomeric isolation components, such as conventional elastomeric O-rings and associated isolation ring material. The method and apparatus can also reduce the need for keys for torque transmission and can avoid the use of auxiliary support wheels to maintain the desired rotary horn and rotary anvil positions.

The horn elements that can be used in the method and apparatus are well known in the art. For example, suitable elements of a rotary ultrasonic sonotrode are disclosed in U.S. Patent No. 5,096,532 entitled ULTRASONIC ROTARY HORN by Joseph G. Neuwirth et al., Issued March 17, 1992; in US Patent No. 5,110,403 entitled HiGh EFFICIENcY ULTRASONIC ROTARY HORN (High Efficiency Rotary Ultrasonic Sonotrode) by Thomas D. Ehlert et al.,

ES 2 395 019 Τ3 issued May 5, 1992; and in US Patent No. 5,087,320 entitled ULTRASONIC ROTARY HORN HAVING IMPROVED END CONFIGURATION (Rotary Ultrasonic Sonotrode Having an Improved End Configuration) by Joseph G. Neuwirth, issued February 11, 1992.

The incorporation of one or more waveguides, such as those provided by shaft element 34, is also well known in the art. The construction and arrangement of a suitable waveguide is conventional, and can be carried out with commonly understood engineering techniques that are used in ultrasonic treatment systems, such as ultrasonic bonding systems.

In the case of the present invention, the node plane of the selected waveguide is a longitudinal node located along the axial direction of the method and apparatus. In the plane of the node, approximately zero longitudinal displacements (eg, axial) occur during normal operation with selected ultrasonic excitations. However, radial displacements can still occur at the longitudinal node.

The elements of the rotary anvil that can be used in the method and apparatus are well known in the art and are available from commercial distributors. Examples of such distributors may include Sonobond, a company with offices located in West Chester, Pennsylvania; and Branson Ultrasonics a company that has offices located in Danbury, Connecticut.

Conventional ultrasonic piezoelectric converters and power sources can be used in the method and apparatus of the invention and are available from commercial distributors. Examples of suitable power ultrasonic systems include the Model 20A3000 system available from Dukane Ultrasonics, which has offices located in St. Charles, Illinois; and the Model 2000CS system available from Herrmann Ultrasonics, which has offices located in Schaumburg, Illinois. In a particular aspect, the method and apparatus may include an ultrasonic piezoelectric converter 82 which is operatively connected to the sonotrode element 28 and is capable of providing an operative amount of ultrasonic energy at a frequency within a range of approximately from 15 to 60 KHz (KiloHerz). It should be noted that other ultrasonic frequencies can also be used.

Referring to Figures 3 through 6A, at least one area of ​​the isolation element 42 can be bent under the selected range of sonotrode-activated sonic frequencies to provide a bending or bending beam type operating component, which is aligned generally transversely to the radial direction of the isolation element. In a particular aspect, the insulating element can provide one or more zones that can exhibit one or more dynamic bending and bending displacements, or movements that are generally directed along the axial direction of the insulating element. For example, the radial isolation component 46 of the isolation element may be configured to provide one or more dynamic bending and flexing displacements that can oscillate reciprocatingly in a path extending generally along of the axial direction of the insulating element. In a desired aspect, the isolation member can be displaced in the manner of a rocking diaphragm. In a more particular aspect, the radial isolation component 46 can be displaced in the manner of an oscillating diaphragm.

The isolating element may also provide one or more zones which may have one or more beam-type bending and bending movements or movements, or movements that are directed generally transversely to the axial direction of the isolating element. In a particular aspect, the insulating element can provide one or more zones that can exhibit one or more dynamic bending and bending displacements, or movements that are generally directed along the radial direction of the insulating element. For example, the axial isolation component 50 may be configured to provide one or more dynamic bending and flexing displacements that can vibrately oscillate with a reciprocating motion in a path extending generally along the direction. radial element of the insulation element. It can be easily understood that in addition to the described bending and bending movements exhibited by the insulating element -42-, said insulating element can undergo other dynamic movements that are usually induced during ordinary ultrasonic bonding operations.

It has been found that lateral translation, dynamic curvature, and bending displacements that can be induced generally along the axial direction and / or the radial direction can help compensate for any misalignment between the position of the isolation member and the position of the plane of the associated node. In a more particular aspect, the dynamic lateral translational curvature and flexural displacements can help to compensate for any mismatch between (a) the physical position in which the isolation element -42- connects with the corresponding element -34- of the axis, and (b) the real position of the plane -38- of the corresponding dynamic node along the axial travel of the corresponding element -34- of the axis. Said mismatches can occur during the operation of the method and the apparatus due to displacements produced by changes in temperature, changes in the frequency of ultrasound, changes in the target material to be worked or the like, as well as combinations thereof.

IS 2 395 019 Τ3

Dynamic bending and curvature displacements that are transverse to the radial and / or axial direction of the isolation member can desirably be provided without generating excessive fatigue on the corresponding isolation member. When a particular insulation element has individually identifiable radial insulation components -46-, and / or individually identifiable axial insulation components -50-, each of said radial and / or axial components may be configured to bend without undue fatigue by means of using conventional parameters and design techniques well known in the art. For example, the length, thickness, modulus of elasticity, and other parameters can be selected and configured to provide the operational curvature and fatigue strength of the radial insulation component. Similarly, the length, thickness, modulus of elasticity, and other parameters can be selected and configured to provide the operational curvature and fatigue strength of the axial insulation component.

In a particular aspect, the isolation member can operate under expected ordinary operating conditions for a minimum of about 4,000 hours without excessive fatigue failure. The isolation element can desirably provide a minimum ultrasound operating life of about 5,000 hours, with substantially no fatigue failure, as determined under expected normal operating conditions and, more desirably, can provide a minimum ultrasound operating life. about 6,000 hours with substantially no fatigue failure.

In a particular aspect, the insulation element may be configured such that during ordinary operation, the insulation element is subjected to a voltage level that is not greater than about 10% of the elastic limit of the insulation element. Alternatively, the insulation element may be configured such that, during ordinary operation, the insulation element is subjected to a voltage level that is not greater than about 1% of the elastic limit of the insulation element.

The isolation element may be configured to operatively bend and reciprocate under a range of sonic frequencies activated by the sonotrode, to provide an operative component of motion along a radial direction, and an operative component of motion through along an axial direction. The range of frequencies driven by the sonotrode may be a range that is approximately ± 3% of the nominal ultrasonic frequency. The nominal frequency is the target ultrasonic frequency at which the method and apparatus are intended to operate to carry out the selected treatment operation.

In various configurations of the method and apparatus of the invention, the radial insulation component may extend discontinuously or substantially continuously along a circumferential direction of the insulation element. Referring to Figures 3 to 6A, the exemplary radial insulation component 46 may be substantially disc-shaped or substantially annular in shape, as desired.

Referring to Figures 3-8, the axial isolation component 50 may be configured to provide a substantially axial extension from the radial isolation component 46. In the example of the arrangement shown by way of example, the axial isolation component -50- may be configured to provide an extension that is directed along the axial direction from a radially outer section to the radial isolation component -46- . The axial isolation component may be configured to provide a discontinuous or substantially continuous extension from the radial isolation component. Additionally, the axial isolation component may be configured to extend discontinuously, or substantially continuously, along a circumferential direction 104 of the isolation member. In the example of the configuration shown by way of example, the axial isolation component 50 may have a substantially cylindrical shape.

In various configurations of the invention, the horn member, the associated shaft member (s), and the associated isolation member (s) may be components that are separately disposed and operatively linked to each other. Alternatively, the horn member, the associated shaft member (s), and the associated isolation member (s) may be integrally formed from a single piece of material that is suitable for fabrication of the ultrasonic bonding devices. For example, the horn element, shaft elements, and isolation elements can be machined from the same piece of bar stock.

With respect to the isolation element -42-, the axial isolation component -50- and the radial isolation component -46- may be separately arranged fragments that are operatively linked together, or they may be integrally formed from the same piece of material that is suitable for the fabrication of ultrasonic bonding devices. For example, the axial insulation component and the radial insulation component can be formed from the same piece of bar stock.

IS 2 395 019 Τ3

In an alternative configuration, the axial isolation component 50 may be independent of the radial isolation component 46. In another feature, the axial isolation component may be integrally formed with an associated coupling element 58. A designated section of the axial isolation component can then be attached and secured to the separately disposed associated radial isolation component 46. As shown by way of example in Figure 10, the radial isolation component can be snapped into the axial isolation component. As shown in FIG. 10A, the radial isolation component may be bolted or otherwise secured to the axial isolation component.

In an optional arrangement, the isolation element -42- may have an axial isolation component -50 that is arranged integrated with the radial isolation component -46-, and the isolation element may be integrally formed with its associated coupling device, as shown by way of example in FIG. 10B. The radial isolation component may be operatively attached to the shaft member 34 with any suitable fastening system.

Another arrangement of the isolation element -42- may have the associated coupling device -58- snapped into the axial isolation component -50- of the isolation element -42-, as shown in FIG. 10C. It will be readily understood that the axial isolation component -50-, the radial isolation component -46- and the shaft element -34- may be further interconnected with each other in any operative configuration.

The method and apparatus may include at least one, and optionally, a number of rotary coupling devices, such as those arranged by one or more coupling devices 58. In the various arrangements of the invention, each coupling device may be configured to be operationally similar to some or all of the other coupling devices. Accordingly, the arrangements, structural features, operating features, or other configurations that have been described with respect to a particular coupling device can be incorporated into the other coupling devices as well.

As shown by way of example in Figures 4 to 10C, the insulating element -42- can be attached to a rotary coupling device -58- which, in turn, can be supported by at least one bearing rotary -66- and by the associated mounting structure. Consequently, the coupling device -58- can be interconnected between the isolation element -42- and the rotary bearing -66-. In a desired configuration, the rotary bearing -66- and the corresponding assembly -70-, can hold and permanently support the rotary coupling device -58-. The bearing assembly may generally be located adjacent to the plane of the shaft member node. Alternatively, the bearing assembly may be separated from the plane of the shaft member node by a significant distance. As shown by way of example, the support bearing assembly 70 may generally be located adjacent to the plane 38 of the node provided by the shaft element 34.

Referring to Figures 6A and 9, the sonotrode element -28- may be supported in a cantilevered position with a series of bearing elements -66- and -66a- and associated support assemblies -70- and -70a- . The coupling device 58 can be extended along its axial dimension, and a pair of bearing elements can be provided with a bearing element positioned proximate each axial end of the coupling device. The bearing elements may be attached to their corresponding mounting brackets so that they can hold the coupling device in a substantially fixed position exhibiting high rigidity and toughness. Appropriate waveguides and intensifier elements can be configured that extend through the coupling device and are operatively connected to shaft element 34 and sonotrode element 28.

In a particular aspect, the method and apparatus of the invention may be configured to provide a rotating sonotrode element 28 exhibiting greatly reduced static deformation. In a desired configuration, the static strain can be about 0.025 mm (about 0.0005 inches) or less, when subjected to a static force of 445 N (100 pounds), directed against the outer peripheral surface -88 of the -28 element. - of the sonotrode in a centered position along the axial dimension of the surface -88-, and along the radial direction of the rotating sonotrode. In other configurations, the static deformation can be a maximum of about 0.76 mm (about 0.03 inches). Alternatively, the horn deformation may not be greater than about 0.5mm (about 0.02 inches) and optionally may not be greater than about 0.3mm (about 0.012 inches) to provide improved effectiveness. In a particular arrangement, the static deformation of the horn element may not be greater than about 0.076mm (about 0.003 inches).

The method and apparatus may be further configured to provide a rotating sonotrode element -28- exhibiting a characteristic low level of dynamic offset: in a desired characteristic, the sonotrode offset may be about 0.0025mm (approximately 0, 00001 inches) or less, at a rotational speed of 5 revolutions per minute. In a further feature, the horn element may have a maximum offset of no more than about 0.018mm (about 0.0007 inches). The horn offset can alternatively be no more than about 0.013 mm (about 0.0005

ES 2 395 019 Τ3 inches), and optionally may not be greater than about 0.01 mm (about 0.0004 inches) to provide better performance.

Referring to the aspects of the invention shown in Figures 3 to 6A, the insulation element -42 may have a radial insulation component -46-, generally of annular shape, which has high stiffness and toughness and is connected and fixed. to the waveguide provided by the element -34- of the shaft. The fixture is located approximately in the expected plane of the waveguide node, the shaft element. An axial isolation component 50, generally cylindrical in shape, may have relatively high stiffness and toughness, and may be connected and attached to an outer distal region of the radial isolation component 46. The axial isolation component may extend from the radial isolation component, in an inner direction, toward the sonotrode element 28 or, in an outer direction, away from the sonotrode element. Alternatively, the axial insulation component can be extended in both the inner and outer directions.

As shown in the arrangements shown in Figures 3 and 4, the axial insulation component 50 may extend in both the inner and outer directions at substantially equal distances. Optionally, the axial insulation component can be extended in both directions, inside and outside, at different, unequal distances. The axial isolation component -50- may include one or more radially projecting substantially annular spacers -51- which support the axial isolation component at a distance away from its corresponding coupling device -58-. As shown by way of example, each pair of spacers 51 may be located at each opposite axial end of the axial isolation component. The gap distance is configured to allow a certain operating amount of dynamic flexural curvature of the axial isolation component.

Referring to the aspects of the invention shown in Figures 5, 6 and 6A, the insulation element 42 may include a radial insulation component 46, generally annular in shape, having high stiffness and toughness and It is connected and fixed to the waveguide provided by the element -34- of the shaft. The fixture is located approximately in the expected plane of the waveguide node, the shaft element. An axial insulation component -50-, generally cylindrical in shape, is configured to have high stiffness and toughness, and is connected and attached to a region of the outer edge of the radial insulation component -46-. The axial isolation component may extend from the radial isolation component in an outward direction, away from the sonotrode element.

In the various arrangements of the method and apparatus, the configuration of the fixture or other operative connection between the shaft member and its corresponding connected isolation member may be substantially free of rubber or other elastomeric components. Consequently, the locking mechanism can provide an operative connection that has high stiffness and toughness and is substantially inelastic.

The isolation member -42- may include a diaphragm-like member and a mounting flange -54-. The diaphragm-like element may include a substantially continuous radial component 46, which has high stiffness and toughness and extends substantially radially from the shaft or other waveguide element 34. Additionally, the radial component -46- may be located approximately in the nodal plane -38- of the shaft element or other waveguide. The radial component may protrude radially outward with a length that can allow this radial component to operatively bend under normal ranges of frequencies activated by the sonotrode, without impairing its fatigue life. Moving outward from the radial component, the structural shape of the isolation member 42 can change to provide an axial component 50 that extends along the axial direction of the isolation member. As shown by way of example, the axial component may have a protruding generally cylindrical shape, substantially parallel to the axis of rotation of the waveguide or shaft element 34.

The lengths of the radial and axial components of the isolation element -42- are large enough to allow these components to bend and flex dynamically under the normal range of radially and axially directed motions that may originate at the node, or near of the same, of a waveguide during its intended operation. In particular, the axial magnitude of the cylindrical shape can dynamically bend and flex under the normal range of radially directed motions that can originate at or near the node of a waveguide. Such radially directed movement can normally be caused by resonance oscillations produced by the ultrasonic energy directed towards the sonotrode element 28. The radial length of the diaphragm shape can be dynamically bent and flexed through the normal range of axially directed motions that can originate at or near the node of a waveguide. Said axially directed movement can also originate due to resonance oscillations produced by the ultrasonic energy directed towards the sonotrode element 28. The combination of the dynamic bending movements of the radial and axial components of the isolation element can act to damp the radial and axial movements induced in the sonotrode -28- and in the waveguide (for example, the element -34- axis) during normal oscillatory expansions and contractions that are excited by the ultrasonic power source. Damping can occur within the normal range of ultrasonic frequencies to which the sonotrode 28 is subjected during normal operation.

IS 2 395 019 Τ3

In a selected area, such as at one end of the outer diameter of the insulation element 42, a mechanism or operative clamping / clamping method can be used to secure and clamp the insulation element to other components of the joint system. ultrasound, such as the coupling device -58-. As shown by way of example, the clamping mechanism may be located, for example, at one end of the outer diameter of the axial insulation component 50. In one arrangement, the isolation member 42 (eg, the axial isolation component 50 of the isolation member) may include a portion 54 of an extending flange. As shown by way of example, the joining flange 54 may include a generally radially extending section, and may include a generally axially extending section. In a desired aspect, the attachment flange may be operatively located and secured in the opening 62 of the coupling device. In another aspect, the flange portion 54 of the coupling device may be operatively secured to the aperture 62 of the coupling device by including a friction interference fit. The flange may, for example, be snapped into a hole opening such as that provided by aperture 62 of the coupling device, and may be held in position, additionally or alternatively, by fasteners.

Alternatively, friction fit interference can be generated by heat expanding the part having the designated opening (eg, coupling device opening 62) and inserting the component or component part that an attempt is made to imprison or hold (for example, the isolation element -42-). When heat dissipates, the opening contracts and helps to secure the inserted component.

In another clamping arrangement, the flange can be appropriately extended, as required, and a clamping device can be used to hold the insulation member in position. Yet another fixation device may incorporate a single extension having a suitable surface for fixation.

In a further aspect, the connecting flange may be substantially contiguous and integrally formed with its corresponding isolation element 42. Optionally, the flange can be a separately arranged component that is subsequently attached to the insulation element.

Additionally, the isolation element may be substantially continuous and integrally formed with its corresponding waveguide or shaft element 34. Consequently, the sonotrode can be held in the selected position more precisely, it can better maintain the desired position when subjected to a much higher load. Additionally, the desired rotary drive torque can be transmitted to the sonotrode 28 more efficiently.

In a desired feature, the coupling device can provide a holding and clamping force that is substantially uniformly distributed around the circumference of the axial isolation component. For example, the coupling device may provide a substantially uniformly distributed compression force for clamping directed substantially radially inward against the axial isolation component. Optionally, the axial isolation component may provide a substantially uniformly distributed compression force for clamping directed substantially radially inwardly against the coupling device.

The coupling device 58 may provide a coupling opening 62 in which the first isolation element 42 is located and operatively fixed. In a particular aspect, the axial isolation component -50- of the isolation element -42- may be located and operatively fixed in the opening -62- of the coupling device (eg, Figures 4 and 6). For example, the coupling device 58 may provide a coupling opening 62, substantially cylindrical in shape, in which the insulation component 50 of the insulation element 42 can be located and operatively attached. The insulating element may, for example, be snap-fitted into the coupling opening.

Optionally, the axial isolation component may be configured to provide an opening in an isolation member and an operative end portion of the coupling device may be located and operatively secured in the opening in the isolation member. For example, the coupling device may be press fit into the opening of the insulation element.

As shown by way of example, the coupling device 58 can be configured to provide a tubular structure in which other components can be operatively located and directed. Referring to Figures 4 and 8, for example, the shaft element 34 may be arranged collinear and coaxial with the coupling device, and the shaft element may extend through the coupling device. Additionally, an ultrasonic intensifier element 74 can be arranged collinear and coaxial with the coupling device, and the intensifier element can extend through the coupling device. In addition, the intensifier element can be operatively connected to the shaft element -34- and an ultrasonic piezoelectric converter -82- can be operatively connected to the intensifier element -74- by using any technique or device.

ES 2 395 019 Τ3 conventional. For example, electrical power can be directed with suitable electrical conductors to a conventional slip ring assembly 78, and the slip ring assembly can be used to direct electrical power directly to the piezoelectric ultrasonic converter 82. The piezoelectric converter can use the electrical power to generate the desired ultrasonic energy and direct the ultrasonic energy to the sonotrode element 28. As shown by way of example, the ultrasonic energy can be directed to the intensifier element 74 through the shaft element 34 and into the sonotrode element.

The method and apparatus may be suitably mounted on a support frame 22. Coupling element 58 may be substantially inelastic supported with a mounting system that is substantially nonelastomeric and has relatively high stiffness and toughness. The mounting system can be substantially free of components made of an elastomer, such as natural or synthetic rubber. In a particular feature, the rotary bearing 66 may be mounted in a substantially inelastic manner, and the mounting system may be substantially free of elastomeric mounting elements, such as those provided by elastomeric O-rings. The support frame is desirably made of a suitable vibration damping material. Various conventional damping materials are well known in the art. For example, the frame can be made of iron, and the iron can have a damping capacity of about 100 to 500.

A desired attachment configuration -96-, or other selected treatment mechanism may be provided on the outer peripheral surface -90- of the rotary anvil element -86-, or it may be provided on the outer peripheral surface -88- of the -element. 28- rotary horn, as desired. In the configuration shown by way of example, the desired attachment arrangement is disposed on the outer circumferential surface 90 of the anvil member 86. The bonding arrangement may be comprised of a series of bonding elements -132- that are configured to project substantially radially away from the outer surface -90- of the anvil element -86- in a manner that is well known. in technique. The joining elements may be distributed discontinuously or substantially continuously in a regular or irregular distribution over the entire outer peripheral surface -90- of the anvil element -86-, or on the outer surface -88- of the element -28- of sonotrode, as desired.

The method and apparatus may be substantially free of rotating supports that are in direct contact with the sonotrode element 28. In particular, the method and apparatus may be substantially free of rotating supports that are in direct contact with the outer peripheral surface 88 of the sonotrode element 28.

In a further aspect, the method and apparatus be substantially free of supports that are in direct contact with the rotating anvil member 86 to maintain a selected position of the rotating anvil member relative to the rotating sonotrode member. More particularly, the method and apparatus may be substantially free of rotating supports that are in direct contact with the outer peripheral surface 90 of element 86 of the anvil.

In the various fasteners and guards used in the constructive forms of the method and apparatus of the invention, it is readily apparent that any conventional fastening and shielding technique can be used. Such techniques can include, for example, adhesives, welds, screws, bolts, rivets, pins, latches, staples, or the like, as well as combinations thereof.

Similarly, it is readily apparent that any conventional material can be used to make the various elements and components of the method and apparatus. Such materials can include synthetic polymers, fiberglass and resin composites, resin and carbon fiber composites, metals, metal composites, ceramic composites, and the like, as well as combinations thereof. For example, suitable metals can include steel, aluminum, titanium, or the like, as well as combinations thereof. Materials are commonly selected to provide desired levels of strength, toughness, low vibration damping, toughness, fatigue resistance, durability, ease of manufacture, and ease of maintenance.

The dimensions of the various components may depend on the particular application of the method and apparatus, and may be determined using standard engineering techniques. For example, component dimensions can be determined by checking the desired peak operating load and determining stress limits with a selected factor of safety (for example, a factor of safety of ten) to help ensure adequate life. and resistance to fatigue.

The rotating sonotrode element 28, corresponding waveguide / shaft elements, corresponding isolation elements, and other associated elements, can be manufactured as a unitary assembly integrally formed from a single piece of material. The one-piece design can eliminate interconnections that can be a source of excessive wear and excessive heat generation. Such interconnections can also contribute to the accumulation of tolerance errors during machining. Such tolerance errors can make it difficult to maintain the desired level of concentricity on the rotating horn work surface. As a result, various method and apparatus configurations can reduce

ES 2 395 019 Τ3 costs, provide increased toughness, can operate with lower tolerance margins, and can provide more regular behavior during high-speed manufacturing.

It will be readily understood that the various rotating components can be dynamically balanced in rotation to reduce wear, reduce vibrations, better hold desired positions, and further improve the performance of the desired joining operation. Each of the components can be dynamically balanced individually or in an operative combination with other components, as desired.