Abstract:
A wand for delivering therapeutic ultrasonic energy to a target area includes a module and a transducer. The transducer converts electrical energy into ultrasonic vibrations that are delivered to the module. The module includes a fluid chamber that houses an ultrasonic fluid. In order to reduce or eliminate the deleterious effects of bubbles that may form in the ultrasonic fluid, one or more bubble traps are defined in the fluid chamber that capture, store, and/or assist in keeping the bubbles outside of the direct transmission path of the ultrasonic energy through the fluid. One or more barriers may be included in the trap(s) that obstruct movement of the bubbles into the transmission path when the wand is tilted to different orientations. After passing through the fluid, the ultrasonic energy is delivered to the skin of a patient, or other surface to which the ultrasonic energy is being directed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. provisional patent application Ser. No. 61/657,316 filed Jun. 8, 2012 by Bradley J. Pippel and entitled Ultrasonic Head Trap, the complete disclosure of which is hereby incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to ultrasonic devices, and more particularly to ultrasonic devices adapted to deliver heat energy to one or more targeted locations. 
         [0003]    Ultrasonic energy may be used to deliver heat energy to a target by focusing the ultrasonic vibrations such that they arrive at the target in a concentrated manner. Such techniques may be useful for delivering ultrasound treatments to human or other animal tissue, particularly treatments intended to treat fatty tissues underlying the skin for cosmetic reasons. Systems for delivering ultrasonic energy to mammalian tissue in order to heat the tissue typically include an ultrasonic transducer, a control system for controlling the ultrasonic transducer, and a fluid chamber coupled to the ultrasonic transducer. The fluid chamber is adapted to focus the ultrasonic energy created by the transducer so that the energy is delivered to the mammalian tissue in the right location and with the desired level of concentration. The fluid inside of the fluid chamber may be in contact with a driving member of the ultrasonic transducer so that the ultrasonic energy is transmitted from the driving member into the fluid, which then passes the ultrasonic energy onto a contact membrane, or other structure that is in physical contact with the human or other mammal. 
         [0004]    In the past, the transmission of ultrasonic energy through the fluid contained within the fluid chamber has been degraded by the presence of any air bubbles, or other gas bubbles. Such bubbles tend to interfere with the transmission of ultrasonic energy from the transducer to the target, decreasing the efficiency of the transfer and/or changing the focusing of the ultrasonic energy. In some cases, the interference of the bubbles may be so detrimental that the ultrasonic energy delivery system has to be replaced, leading to waste and increased costs. 
       SUMMARY OF THE INVENTION 
       [0005]    Accordingly, the present invention overcomes and/or reduces the disadvantages of bubbles associated with ultrasonic heat energy delivery systems. According to one aspect, one or more bubble traps are provided that capture, maintain, and/or assist in keeping bubbles in one or more locations outside of the direct ultrasonic energy transmission path through the fluid, thereby reducing or eliminating any interference the bubbles would otherwise create with the transmission of ultrasonic energy through the fluid. In other aspects, an ultrasonic energy delivering wand is provided that includes a bubble trap for storing bubbles out of the direct transmission path of the ultrasonic energy, and/or for capturing bubbles that may temporarily be in the direct transmission path. In yet other embodiments, a method may be provided for delivering ultrasonic energy in a manner that reduces interference from any bubbles present in an ultrasonic fluid medium through which the ultrasonic energy passes. The methods, apparatus, and systems of the present invention can be applied to any energy transmission media, whether fluid or otherwise, in which bubbles may form. 
         [0006]    According to a first embodiment, an ultrasonic module for transmitting ultrasonic energy from a transducer to a target is provided. The module includes a first end for receiving ultrasonic energy from an ultrasonic transducer, and a second end for delivering ultrasonic energy to a target, a fluid chamber, and a bubble trap. The fluid chamber is positioned between the first and second ends and is adapted to contain an ultrasonic fluid. The bubble trap is adapted to hold bubbles formed in the ultrasonic fluid in a location outside of a direct ultrasonic energy transmission path defined between the first and the second ends. 
         [0007]    The module may further include a seat defined at the first end for positioning an ultrasonically vibrating member, and a barrier surrounding the seat that obstructs bubbles in the bubble trap from escaping out of the bubble trap and into the transmission path. The barrier may prevent bubbles in the bubble trap from escaping out of the bubble trap and into the transmission path when the module is tipped from a vertical orientation to a tipped orientation, wherein the vertical orientation is defined by the first and second ends being vertically aligned, and the tipped orientation is defined by the first and second ends not being vertically aligned. In some embodiments, the tipped orientation may include angular deviations as great as ninety degrees from the vertical orientation such that bubbles are retained in the trap for all angular deviations up to at least ninety degrees from the vertical orientation. 
         [0008]    The module may be configured to capture bubbles positioned in the transmission path whenever the module is tipped such that the first and second ends are not vertically aligned. The bubble trap may be positioned closer to the first end than to the second end. The fluid chamber may include a first section and a second section, wherein the first section includes a first inner dimension and the second section includes a second inner dimension that is smaller than the first inner dimension. The bubble trap may be defined in the first section. A barrier may be defined adjacent a junction of the first and second sections wherein the barrier obstructs bubbles from escaping out of the bubble trap and into the transmission path. 
         [0009]    In some embodiments, both a first barrier and a second barrier may be provided. The first barrier may be defined near the first end and adapted to obstruct bubbles in the bubble trap from escaping out of the bubble trap and into the transmission path, and the second barrier may be defined between the first barrier and the second end, wherein the second barrier is also adapted to obstruct bubbles in the bubble trap from escaping out of the bubble trap and into the transmission path. The first barrier may be adapted to obstruct bubbles when the first end is positioned higher than the second end, and the second barrier may be adapted to obstruct bubbles when the second end is positioned higher than the first end. 
         [0010]    The module may include a releasable fastening system for releasably securing the module to an ultrasonic transducer such that the module may be discarded without discarding the ultrasonic transducer. The module may also be attached to the ultrasonic transducer by way of a plurality of apertures adapted to receive a plurality of fasteners having a length sufficient to extend into a plurality of corresponding apertures defined in the ultrasonic transducer such that, when the fasteners are inserted into the apertures and the corresponding apertures, the module is secured to the ultrasonic transducer. 
         [0011]    According to another embodiment, a hand-held ultrasonic wand for delivering heat energy to human tissue using ultrasonic energy is provided. The wand includes an ultrasonic transducer, a fluid chamber, and a bubble trap. The ultrasonic transducer is adapted to convert electrical energy into ultrasonic energy. The fluid chamber is coupled to the ultrasonic transducer and adapted to contain an ultrasonic fluid through which the ultrasonic energy is transmitted. The bubble trap is defined within the fluid chamber and is adapted to hold bubbles formed in the ultrasonic fluid in a location outside of a direct ultrasonic energy transmission path defined between the ultrasonic transducer and the first and second ends. 
         [0012]    The wand may include a first barrier defined in the fluid chamber near the ultrasonic transducer that is adapted to obstruct bubbles in the bubble trap from escaping out of the bubble trap and into the transmission path, as well as a second barrier defined in the fluid chamber and spaced away from the second barrier wherein the second barrier also is adapted to obstruct bubbles in the bubble trap from escaping out of the bubble trap and into the transmission path. The first barrier may be adapted to obstruct bubbles when the wand is positioned above the human tissue, and the second barrier may be adapted to obstruct bubbles when the wand is positioned below the human tissue. 
         [0013]    The wand may also include a releasable fastening system for releasably securing the fluid chamber to the ultrasonic transducer such that the fluid chamber may be discarded without discarding the ultrasonic transducer. A seat may be defined in the fluid chamber for receiving a driver of the ultrasonic transducer, and a contact membrane may be positioned at an end of the fluid driver in a location where it is adapted to contact human skin when delivering ultrasonic energy to the human tissue. The bubble trap may hold bubbles therein when the wand is tilted up to at least as much as ninety degrees from a vertical orientation, wherein the vertical orientation is defined by vertical alignment of the seat with the contact membrane. The wand may further be adapted to hold bubbles therein when the wand is rotated three-hundred and sixty degrees around a vertical axis while being tilted up to at least as much as ninety degrees from the vertical axis. 
         [0014]    The wand may also be adapted to capture bubbles positioned in the transmission path whenever the wand is tipped such that the seat and the contact membrane are not vertically aligned. The fluid chamber may include a first section and a second section, wherein the first section is positioned adjacent the ultrasonic transducer, and the second section is positioned away from the ultrasonic transducer. The bubble trap may be defined in the first section. The first section may include a first inner dimension and the second section may include a second inner dimension that is smaller than the first inner dimension. The ultrasonic transducer may include a driver portion having a non-planar surface in contact with the ultrasonic fluid, wherein the non-planar surface urges the bubbles toward the bubble trap whenever the bubbles push against the non-planar surface of the driver portion. 
         [0015]    According to yet another embodiment, a method for delivering ultrasonic energy to a target in order to create heat at the target is provided. The method includes generating ultrasonic vibrations in a driver portion of an ultrasonic transducer; transmitting the ultrasonic vibrations of the driver portion through a transmission path of an ultrasonic fluid that is in contact with the driver portion; and capturing bubbles in a location outside of the transmission path such that the bubbles do not interfere with the transmission of the ultrasonic vibrations through the fluid toward the target. 
         [0016]    The method may further include retaining bubbles in the location outside of the transmission path when the ultrasonic transducer is tilted as much as at least ninety degrees from a vertical orientation. In another embodiment, the method may also include retaining bubbles in the location outside of the transmission path when the ultrasonic transducer is tilted as much as at least ninety degrees from a first vertical orientation, wherein the first vertical orientation is defined with the transducer positioned above the fluid; and also retaining bubbles in the location outside of the transmission path when the ultrasonic transducer is tilted as much as at least ninety degrees from a second vertical orientation, wherein the second vertical orientation is defined with the fluid being positioned above the transducer. 
         [0017]    The method may also include storing the fluid in a fluid chamber that may be released from the transducer to allow a different fluid chamber to be attached to the transducer. The method may alternatively include storing the fluid in a fluid chamber that is permanently affixed to the transducer. 
         [0018]    In any of the foregoing embodiments of the module, wand, and/or method, the target may be human tissue and the fluid and/or fluid chamber may be adapted to focus the ultrasonic energy in order to generate heat within the human tissue. A contact membrane may also be added to the fluid chamber that is adapted to contact the patient&#39;s skin when delivering ultrasonic energy to the tissue. The ultrasonic fluid may be an acoustic gel. 
         [0019]    Before the various embodiments of the invention are explained in detail below, it is to be understood that the invention is not limited to the details of operation or to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention may be implemented in various other embodiments and is capable of being practiced or being carried out in alternative ways not expressly disclosed herein. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof. Further, enumeration may be used in the description of various embodiments. Unless otherwise expressly stated, the use of enumeration should not be construed as limiting the invention to any specific order or number of components. Nor should the use of enumeration be construed as excluding from the scope of the invention any additional steps or components that might be combined with or into the enumerated steps or components. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]      FIG. 1  is a diagram of an ultrasonic energy delivery system according to one aspect of the invention that is adapted to deliver ultrasonic energy to a patient; 
           [0021]      FIG. 2  is a diagram of the ultrasonic energy delivery system of  FIG. 1  shown in an upside-down orientation in comparison to the orientation of  FIG. 1 ; 
           [0022]      FIG. 3  is a bottom view of an ultrasonic module that is part of the ultrasonic energy delivery system of  FIGS. 1 and 2 ; 
           [0023]      FIG. 4  is a sectional view of the ultrasonic module taken along the line IV-IV in  FIG. 3 ; 
           [0024]      FIG. 5  is a sectional view of the ultrasonic module taken along the line V-V in  FIG. 3 ; 
           [0025]      FIG. 6  is a sectional view of the ultrasonic module taken along the line VI-VI in  FIG. 3 ; 
           [0026]      FIG. 7  is the same sectional view as  FIG. 4  but flipped upside down in order to illustrate a different potential orientation of the ultrasonic module; 
           [0027]      FIG. 8  is a sectional view similar to  FIG. 4  of a first alternative embodiment of an ultrasonic module according to another aspect of the present invention; 
           [0028]      FIG. 9  is an elevational view of the ultrasonic module of  FIG. 8  viewed from the direction of arrow  100  in  FIG. 8 ; 
           [0029]      FIG. 10  is a sectional view similar to  FIG. 8  of a second alternative embodiment of an ultrasonic module according to another aspect of the present invention; and 
           [0030]      FIG. 11  is an elevational view of the ultrasonic module of  FIG. 10  viewed from the direction of arrow  100  in  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0031]    An ultrasonic delivery system  20  according to one embodiment is shown in  FIG. 1 . Ultrasonic delivery system  20  includes an ultrasonic wand  22  and an external controller  24 . Wand  22  includes an ultrasonic transducer  26  and an ultrasonic module  28 . Wand  22  is adapted to be applied to the skin  30  of a patient in order to deliver ultrasonic energy to a target area  32 . The delivery of the ultrasonic energy to the target area  32  is adapted to generate heat, and, in some embodiments, the delivery of heat is useful for cosmetic purposes. It will, however, be understood by those skilled in the art that the delivery of ultrasonic energy to target area  32  may be for any useful purpose, whether cosmetic or otherwise. It will further be understood by those skilled in the art that the position of the target area  32  may vary from that shown in  FIGS. 1 and 2 . That is, in some embodiments, target area  32  may be positioned internally under the skin  30 , such as shown in  FIGS. 1 and 2 , while in other embodiments target area  32  may be on or nearer to the surface of the patient&#39;s skin  30 . 
         [0032]    Controller  24  includes the electrical circuitry necessary for controlling wand  22  and delivering ultrasonic energy to target area  32 . In some embodiments, controller  24  may be external to wand  22 , such as is shown in  FIGS. 1 and 2 . However, in other embodiments, controller  24  may be incorporated inside of wand  22 . When so incorporated, it may be possible to dispense with control cable  34 . Indeed, in such an embodiment, wand  22  could be completely cable free (if an internal source of power is provided), or it may include only a power cable. The circuitry of controller  24 , whether internal or external, could be any conventional circuitry suitable for implementing the desired delivery of ultrasonic energy to a target area. 
         [0033]    Transducer  26  is adapted to convert electrical energy into ultrasonic vibrations that may be focused and delivered to the target area  32 . Transducer  26  may utilize any known or conventional techniques for converting electrical energy to ultrasonic energy. In one embodiment, transducer  26  may include piezoelectric material that physically changes shape when an electrical voltage is applied thereto. By applying an appropriately varying voltage to the piezoelectric material, the material may be driven to vibrate with ultrasonic frequency. The ultrasonic vibrations created by transducer  26  are delivered to module  28 , which focuses the ultrasonic energy and delivers it to the target area  32 . 
         [0034]    Wand  22  is adapted to be used in any desired orientation. That is, wand  22  may direct ultrasonic energy to target area  32  when wand  22  is positioned above the target area  32  (as shown in  FIG. 1 ), or when wand  22  is positioned underneath the target area  32  (as shown in  FIG. 2 ), or in any of the intermediate orientations (not shown) defined between the two vertical orientations shown in  FIGS. 1 and 2 . Thus, wand  22  can deliver ultrasonic energy to a target area no matter what its orientation is with respect to the target area. 
         [0035]      FIGS. 3-7  illustrate module  28  in greater detail. Module  28  includes a receiving end  48  and a delivery end  50  ( FIGS. 4-7 ). Receiving end  48  is adapted to receive ultrasonic vibrations from transducer  26 , while delivery end  50  is adapted to deliver the ultrasonic vibrations to the patient and, more specifically, target area  32  of the patient. Module  28  includes a base  36  positioned at delivery end  50  and a cover  38  that is positioned at receiving end  48 . Cover  38  is adapted to be secured to base  36  such that the cover  38  and base  36  may be secured together to thereby define a fluid chamber  40  when so secured ( FIGS. 4-7 ). A transducer aperture  42  is defined in cover  38  and dimensioned to receive a head portion of transducer  26 . Cover  38  further defines a seat  44  that is dimensioned to receive a driver or driver portion  46  of transducer  26 . 
         [0036]    Fluid chamber  40  includes a first section  56  and a second section  58  ( FIG. 4 ). First section  56  is positioned adjacent receiving end  48  of module  28  and abuts second section  58  on a side opposite receiving end  48 . Second section  58  is defined adjacent delivery end  50  of module  28  and abuts first section  56  on an opposite side. As will be discussed in greater detail below, a bubble trap  60  is defined around the interior perimeter of first section  56  that helps to prevent bubbles formed in the ultrasonic fluid inside of fluid chamber  40  from migrating into a transmission path  54  of the ultrasonic energy. First section  56  includes a first interior dimension D 1  while second section  58  includes a second interior dimension D 2  ( FIG. 5 ). While the precise value of interior dimensions D 1  and D 2  will vary depending upon the height at which they are measured (i.e. how far toward or away from receiving end  48  and/or delivery end  50 ), it can be seen that dimension D 1  is larger than dimension D 2  at all of the different heights. 
         [0037]    Driver  46  may be made of piezoelectric material such that an appropriately varying voltage applied thereto causes it to vibrate at an ultrasonic frequency, or it may be made of another material that is caused to ultrasonically vibrate due to its physical contact with another vibrating structure within transducer  26 . Regardless of the construction of transducer  26 , when wand  22  is activated, the head portion of the transducer will cause driver  46  to vibrate at an ultrasonic frequency. 
         [0038]    The vibration of driver portion  46  causes a corresponding vibration of an ultrasonic fluid that is contained within fluid chamber  40 . The ultrasonic fluid may be any known or conventional fluid used for transmitting ultrasonic vibrations. The ultrasonic fluid may include fluids with high viscosity, as well as fluids with low viscosity, and also fluids exhibiting viscoelastic properties. In one embodiment, the fluid may be an ultrasonic gel. Some examples of fluids that may be used include water or glycerin, although it will be understood by those skilled in the art that other fluids may be used, and that this list of acceptable fluids is only a non-limiting list of examples. The term “fluid” and/or “ultrasonic fluid” as used herein will refer to not only liquids (which may have any range of viscosity), but also to any transmission media in which bubbles may form, including, but not limited to, colloids, emulsions, substances exhibiting mesophases, and other states of matter. 
         [0039]    The ultrasonic vibrations created in the ultrasonic fluid travel away from driver portion  46 , which is positioned at receiving end  48  of module  28 , toward a contact membrane  52  that may be positioned at the extreme end of delivery end  50 . Contact membrane  52  may be any conventional material that is adapted to contact the patient&#39;s skin and to transfer the ultrasonic vibrations to the target area within the patient. Examples of some suitable materials that may be used for contact membrane  52  include polycarbonate, polyetherimide or polypropylene, although it will be understood by those skilled in the art that other materials may also be used. 
         [0040]    The transmission of ultrasonic energy from driver portion  46  to contact membrane  52  follows a direct transmission path  54  that is highlighted in  FIG. 4 . More specifically, the outer boundaries of transmission path  54  are shown in  FIG. 4  in dashed lines. These outer boundaries are generally defined by straight lines that extend from the outer edges of driver portion  46  to the outermost interior edges of second section  58 . 
         [0041]    The ultrasonic waves created in the ultrasonic fluid initially pass through an interior region of first section  56  before continuing on through second section  58 . While it is expected that the ultrasonic vibrations created by driver portion  46  will also travel outside of transmission path  54 , transmission path  54  defines the direct transmission path between driver portion  46  and contact membrane  52 . It is within this direct transmission path  54  that any bubbles are desirably removed. Bubbles positioned outside of this transmission path  54  will have minimal, if any, effect on the transmission of ultrasonic energy to target area  32 . 
         [0042]    As was noted, bubble trap  60  is defined generally in first section  56  of base  36 . More specifically, bubble trap  60  is defined around the outside perimeter of transmission path  54  such that bubbles inside of bubble trap  60  do not cause any significant interference with the flow of ultrasonic energy down transmission path  54 . While the precise shape of bubble trap  60  may vary from one embodiment to another, in the examples shown in  FIGS. 4-6 , bubble trap  60  includes a first barrier  62  positioned around the edges of seat  44  and a second barrier  64  positioned at the junction of first section  56  with second section  58 . Both first and second barriers  62  and  64  extend around the entire interior perimeter of fluid chamber  40 . In other words, first barrier  62  completely circumscribes seat  44 , while second barrier  64  extends completely around the fluid chamber  40  such that it forms a single continuous ridge-like structure. 
         [0043]    First and second barriers  62  and  64  serve to obstruct bubbles contained within trap  60  from migrating into transmission path  54 . This obstruction is carried out by a combination of gravity and the shape of first and second barriers  62  and  64 . In some situations, it is expected that wand  22  will be oriented such that transducer  26  will be positioned either wholly or partially above module  28  (such as shown in  FIG. 1 ). In other situations, wand  22  may be held in an orientation in which module  28  is positioned above transducer  26 , such as that illustrated in  FIG. 2 . Wand  22  may also be held in an intermediate orientation between those illustrated in  FIGS. 1 and 2 . The operation of bubble trap  60  will be explained more fully below with respect to both of the orientations shown in  FIGS. 1 and 2 , as well as the intermediate orientations. 
         [0044]    Beginning with the orientation shown in  FIG. 1 , in which module  28  is oriented in the same manner as in  FIG. 7 , the operation of bubble trap  60  will be explained. While in this orientation, or any intermediate orientation in which transducer  26  is positioned above module  28 , any bubbles formed in the ultrasonic fluid will move upward (opposite the direction of gravity) toward cover  38 . Depending upon the initial position of the bubble, it will continue to move upward until it impacts one of a top surface  66  of bubble trap  60 , an exterior edge  68  of driver portion  46 , or a flat surface  70  of first barrier  62  (see  FIG. 7 ). If the bubble impacts top surface  66  of trap  60 , the shape of trap  60 —including first barrier  62 —will tend to retain the bubble therein such that it cannot escape and migrate into transmission path  54 . This will be explained in greater detail below. 
         [0045]    If the bubble impacts either exterior edge  68  of driver portion  46  or flat surface  70  of first barrier  62 , the bubble may tend to stop and remain in that position provided two conditions are met. First, the wand  22  cannot be tilted, and second, there can be no fluid movement within fluid chamber  40 . Because both of these conditions are unlikely to occur for any extended period of time (due to a person moving and/or tilting wand  22  during use), any bubbles positioned adjacent exterior edge  68  of driver portion  46  or flat surface  70  of first barrier  62  will eventually migrate in one direction or another toward bubble trap  60 . Once the bubble has migrated past barrier  62 , it will become trapped in trap  60 . More specifically, once the bubble moves past barrier  62 , the tendency of the bubble to move upwardly (i.e. opposite the force of gravity) will cause the bubble to move into contact with top surface  66  of trap  60 . 
         [0046]    Once a bubble is in the top portion of trap  60  (i.e. near top surface  66 ), it will be prevented from migrating out of the trap by either a side wall  72  of barrier  62  or an outer wall  74  of trap  60  ( FIG. 7 ). Which of these two walls  72  and  74  initially prevents the bubble from escaping from trap  60  will depend upon how wand  22 , and thus module  28 , is tipped, as well as the initial position of the bubble. Suppose, for example, that module  28 —as shown in FIG.  7 —is tipped such that a left side  76  is raised higher than a right side  78 , and also suppose that a bubble is initially positioned in the portion of trap  60  adjacent right side  78 . This bubble will initially migrate toward side wall  72  of barrier  62 . Once it impacts side wall  72 , however, it will be prevented from migrating further toward transmission path  54  by side wall  72 . In fact, side wall  72  will continue to obstruct any movement of the bubble toward transmission path for any tipping of module  28  that is less than ninety degrees. 
         [0047]    When module  28  is rotated ninety degrees (clockwise with respect to  FIG. 7 ), side wall  72  will no longer be vertical as shown in  FIG. 7 , but will instead be horizontal. The upward vertical force of the bubble will therefore still urge the bubble toward side wall  72 , however, no physical structure will prevent the bubble from moving laterally. Further, if module  28  is tipped more than ninety degrees, side wall  72  will be angled such that it will urge a bubble pressing against it toward transmission path  54 . However, any such bubble that moves beyond side wall  72  toward transmission path will likely move completely through transmission path  54  all the way over to the portion of bubble trap  60  positioned near left side  76  because this portion of trap  60  will be positioned higher than any fluid in transmission path  54 , and the bubble&#39;s natural tendency to move to the highest position in the fluid will therefore carry it into this portion of trap  60 . 
         [0048]    Thus, if module  28  is tipped or rotated in a clockwise fashion (with respect to  FIG. 7 ) any amount equal to or less than ninety degrees, any bubble that initially starts out on a right side  78  of trap  60  will be prevented from escaping from trap  60  by barrier. Further, if module  28  is rotated clockwise more than ninety degrees, such a bubble may escape out of trap  60 , but such escape will likely only be temporary as the bubble floats completely through transmission path  54  and eventually re-enters trap  60  on an opposite side. 
         [0049]    It should be further pointed out that, even in some situations where wand  22  is tipped more than ninety degrees in a clockwise fashion (with reference to  FIG. 7 ), a bubble positioned initially in the right side  78  portion of trap  60  might still not escape from trap  60 . This is because, in response to the tipping, the bubble may move either into or out of the plane of the page defined by  FIG. 7  (due to the curvature of barrier  62  when viewed from either above or below (e.g.  FIG. 3 ). This movement may be sufficient to allow the bubble to completely stay out of transmission path  54  at all times while it migrates toward the portion of trap  60  adjacent left side  76  (of  FIG. 7 ). An example of this potential movement is illustrated in  FIG. 3  by arrows  86  and  88 . Depending upon the degree and orientation of the tilting, as well as the initial position of the bubble, it may migrate in either direction  86  or  88  such that it circumnavigates transmission path  54  on its journey toward the opposite side of module  28 . 
         [0050]    When module  28  is rotated in a clockwise direction ( FIG. 7 ), any bubbles that are initially positioned in trap  60  adjacent left side  76  will remain in the left portion of trap  60 . This is true even if module  28  is rotated beyond ninety degrees. Indeed, if module  28  is rotated 180 degrees clockwise (with respect to  FIG. 7 ), any bubbles that are initially positioned in trap  60  adjacent left side  76  will migrate along outer wall  74  until they end up trapped adjacent second barrier  64 , as will be discussed in more detail below. However, before turning to a further discussion of second barrier  64 , it should be noted that the same type of bubble trapping will occur if the module  28  of  FIG. 7  is rotated counterclockwise. That is, the counterclockwise rotation will tend to urge bubbles toward a portion of trap  60  that is near right side  78 . If bubbles are initially positioned near left side  76 , they may get caught by barrier  62  and prevented from migrating through transmission path  54  unless such counterclockwise rotation exceeds ninety degrees. Even if it does exceed ninety degrees, some bubbles initially on left side  76  of trap  60  may still completely avoid traveling through transmission path  54  by moving into or out of the plane defined by the page of  FIG. 7 , and thus staying in bubble trap  60  during their complete journey over toward right side  78 . Still further, those bubbles initially positioned in trap  60  near right side  78  will remain in trap  60  toward right side  78 . 
         [0051]    To the extent the counterclockwise rotation of module  28  (as shown in  FIG. 7 ) continues past ninety degrees, the bubbles in trap  60  on the right side  78  of module  28  will continue to migrate along outer wall  74 . If such counterclockwise rotation continues for 180 degrees, the bubbles will eventually end up adjacent lower or second barrier  64 . Second barrier  64 , as will be discussed more below, operates in a similar fashion to first barrier  62 , except that it performs its functions when module  28  is tipped upside down (i.e. when wand  22  is oriented such that module  28  is positioned above transducer  26 , examples of such an orientation are shown in FIGS.  2  and  4 - 6 ). 
         [0052]    It will be understood by those skilled in the art that the precise shape of side wall  72  and outer wall  74  may be changed from that illustrated. For example, the shape of side wall  72  could be changed so that it was concavely shaped (as viewed in  FIG. 7 ), and thus it would be able to capture bubbles therein even when module  28  was tipped more than ninety degrees. Further, side wall  72  could have its shape changed so that it did not include any flat portions when viewed from above or below (e.g.  FIG. 3 ). By replacing the flat sections with curved sections, any tipping of the wand  22  would cause bubbles that were abutting side wall  72  to experience a force that tended to urge them to circumnavigate transmission path  54  in either a clockwise or counterclockwise direction (e.g. in the directions of arrows  86  or  88  in  FIG. 3 ). This could help prevent any bubbles from crossing transmission path  54 . Still other variations are possible. 
         [0053]    It will further be understood by those skilled in the art that the shape of exterior edge  68  of driver portion  46  could be changed from the planar shape illustrated in  FIGS. 4-7  to a non-planar shape. Still further, the shape of flat surface  70  could be changed so that it was not horizontal (in the orientation of  FIG. 7 ), but was instead angled upwardly such that its edge closest to side wall  72  was higher than its edge closest to driving member  46  (as viewed in  FIG. 7 ). Either of these variations could facilitate the migration of bubbles toward trap  60  whenever module  28  was positioned in the vertical orientation of  FIG. 1  or  7 . In these perfectly vertical orientations, any bubbles in the transmission path that migrated up to driver  46  or flat surface  70  might tend to stay within transmission path  54  until module  28  was tipped. However, by angling flat surface  70  and/or changing exterior edge  68  of driver  46  to be non-planar, the bubbles could be directed outwardly toward trap  60 . 
         [0054]    Barrier  64  will now be described with reference to FIGS.  2  and  4 - 6 . As noted, barrier  64  operates in substantially the same manner as barrier  62 . The primary difference is that barrier  64  prevents bubbles from escaping trap  60  when module  28  is delivering ultrasonic energy upwardly (e.g. FIGS.  2  and  4 - 6 ), while barrier  62  prevents bubbles from escaping trap  60  when module  28  is delivering ultrasonic energy downwardly (e.g.  FIGS. 1 and 7 ). Just as barrier  62  includes a side wall  72  that obstructs nearby bubbles from migrating into transmission path  54 , barrier  64  likewise includes a side wall  80  that functions in the same manner. Thus, when module is tipped in a clockwise or counterclockwise direction (with respect to  FIG. 2  or  4 - 6 ), side wall  80  of barrier  64  will prevent nearby bubbles from entering transmission path  54  provided such tipping does not exceed ninety degrees from vertical (as defined by gravity). Tipping greater than ninety degrees may allow a bubble to escape into transmission path  54 , however, this will depend upon whether the bubble is positioned adjacent a curved section of barrier  64  or a flat section of barrier  64 . If positioned along a curved section, the curvature may urge the bubble to travel around, rather than through, transmission path  54 . In any event, bubbles traveling through transmission path  54  will likely re-enter trap  60  on the opposite side. Thus, bubbles in trap  60  will be substantially prevented from escaping therefrom for virtually all orientations of wand  22 , and even in those orientations where a bubble may cross transmission path  54 , the traversal of path  54  will like only be temporary until the bubble re-enters trap  60  on an opposite side. 
         [0055]    It will be understood that the examples of tipping described herein are not the only types of tipping in which bubbles are retained within trap  60 . That is, module  28  may be tipped in other orientations beyond the purely orthogonal directions shown in  FIGS. 4-7 . For example, module  28  may be tipped a certain amount such that it rotates clockwise in  FIG. 4   a  certain amount, as well as also simultaneously being tipped a certain amount such that it also rotates clockwise in  FIG. 6 . In such situations where there is a non-zero amount of tipping in two orthogonal directions, barriers  62  and  64  will serve to prevent bubbles from migrating into transmission path in the same manners described above. Indeed, module  28  may have its vertical axis  90  ( FIG. 4  or  6 ) tipped, and then have the component of its vertical axis  90  that is projected into the horizontal plane rotated three-hundred and sixty degrees around a gravitationally vertical axis without having any bubbles escape from traps  60 . 
         [0056]    As shown more clearly in  FIGS. 4 ,  5 , and  7 , module  28  may include a plurality of fastener apertures  82  that are adapted to receive fasteners for securing module  28  to transducer  26 . Fastener apertures  82  may be internally threaded so as to threadingly mate with threaded fasteners, or they may be configured in different manners. The fasteners inserted into apertures  82  are sufficiently long so as to extend into corresponding apertures (not shown) defined in transducer  26 . In this manner, the fasteners can secure module  28  to transducer  26 . The securement of module  28  to transducer  26  may be either permanent or temporary. That is, in some embodiments, the fasteners may allow module  28  to be removed from transducer  26  so that the module may be discarded, if no longer useful, or repaired separately from transducer  26 . In other embodiments, module  28  may be permanently secured to transducer  26  such that any non-repairable malfunction of either module  28  or transducer  26  will require the entire wand  22  to be discarded. 
         [0057]    Cover  38  and base  36  of module  28  may be made from any suitable material. Examples of such suitable materials include polycarbonate, polyetherimide or polypropylene, although it will be understood by those skilled in the art that these examples are not limiting, and that other materials may be used. Cover  38  may be secured to base  36  in any suitable manner. This may involve ultrasonic welding, RF welding, the use of adhesives, or any other techniques that are suitable for creating a fluid-impermeable seal between base  36  and cover  38 . In some embodiments, it may be suitable to replace base  36  and cover  38  with a one-piece unit that defines fluid chamber  40  and that includes a sealable aperture for injecting the interior with the ultrasonic fluid. Still other variations are possible. 
         [0058]      FIGS. 8-9  illustrate a modified ultrasonic module  128  that may be used with the ultrasonic energy delivery system  20  described above, as well as with other ultrasonic energy delivery systems. Modified ultrasonic module  128  includes a substantial number of components that are the same as those found in module  28 , and those common components are labeled in  FIGS. 8-9  with the same reference numbers used to describe module  28 . These common components function in the same manner as has been described above and may be made of the same materials as has been described above with respect to module  28 . Accordingly, repeated description of these common components is not necessary. In addition to these common components, modified ultrasonic module  128  also includes several new components that have been labeled with new numbers. 
         [0059]    Modified ultrasonic module  128  differs from module  28  in that it includes a modified second section  158  having a delivery end bubble trap  94  positioned adjacent contact membrane  52 . The delivery end bubble trap  94  is designed to help remove bubbles from the ultrasonic transmission path  54  that form in, or migrate to, a close proximity of contact membrane  52 . In the embodiment shown in  FIGS. 8 and 9 , delivery end bubble trap  94  is defined by angled sidewalls  92 . More specifically, there are two angled sidewalls  92  defined in module  128 : a first one of which is positioned adjacent contact membrane  52  along left side  76  and a second one of which is positioned adjacent contact membrane  52  along right side  78 . Angled sidewalls  92  provide space for bubbles to migrate to that is not contained within transmission path  54 . 
         [0060]    The space provided for bubbles by delivery end bubble trap  94  is better shown in  FIG. 9 , which is an end view of the module  128  of  FIG. 8  viewed from the direction of arrow  100  in  FIG. 8 . Angled sidewalls  92  are shown at right and left sides  78  and  76 , respectively, and these create a relatively large gap between transmission path  54  and the angled sidewalls  92 . This gap provides space for bubbles to reside which does not interfere with the transmission of ultrasonic energy to membrane  52 . Although bubble traps  94  do not include any lips, ledges, or barrier walls that prevent bubbles from migrating out of bubble traps  94  and into transmission path  54 , the normal usage of ultrasonic energy delivery system  20  will normally not take place in a perfectly vertical and stationary orientation, such as that shown in  FIG. 8 . Instead, the module  128  will likely be tipped and moved to non-vertical orientations. When in such non-vertical orientations, any bubbles in transmission path  54  will tend to move to the side ( 76  or  78 ) of module  128  that is at a higher elevation. Consequently, such bubbles will tend to move toward the higher of the two bubble traps  94  (when module  128  is oriented generally upside down from the orientation shown in  FIG. 8 ). When module  128  is oriented generally as shown in  FIG. 8 , or tipped somewhat, any bubbles in traps  94  will tend to slide upward along sidewall  92  and into trap  60 . 
         [0061]      FIGS. 10-11  illustrate a second modified ultrasonic module  228  that may be used with the ultrasonic energy delivery system  20  described above, as well as with other ultrasonic energy delivery systems. Modified ultrasonic module  228  includes a substantial number of components that are the same as those found in modules  28  and  128 , and those common components are labeled in  FIGS. 10-11  with the same reference numbers used to describe module  28  and/or module  128 . These common components function in the same manner as has been described above and may be made of the same materials as has been described above with respect to module  28  and/or module  128 . Accordingly, repeated description of these common components is not necessary. 
         [0062]    Ultrasonic module  228  includes a modified second section  258  having a delivery end bubble trap  294  positioned adjacent contact membrane  52 . Delivery end bubble trap  294  differs from bubble trap  94  of module  128  in two primary ways. First, delivery end bubble trap  294  includes a curved wall  296  instead of an angled and generally straight sidewall  92 . Second, delivery end bubble trap  294  extends circumferentially around the entire transmission path  54 , as can best be seen in  FIG. 11 . That is, instead of residing primarily only at right and left sides  78  and  76 , as bubble trap  94  does, bubble trap  294  extends between the right and left side  78  and  76 , as well as residing at right and left sides  78  and  76 . Tipping ultrasonic module  228  either forwardly or rearwardly out of the plane of the page of  FIG. 10  will cause any bubbles positioned nearby to move forwardly or rearwardly out of interference with transmission path  54 . 
         [0063]    It will be understood by those skilled in the art that bubble traps  94  and/or  294  can be used in still other embodiments where there are no additional bubble traps. That is, in some additional embodiments, module  128  or  228  can be modified so as to exclude bubble trap  60  and only rely on bubble traps  94  and/or  294 . It will further be understood by those skilled in the art that the angled walls  92  of module  128  could be replaced with curved walls, such as curved walls  296  of module  228 , or other types of curved walls. Similarly, the curved walls  296  of module  228  could be replaced with angled walls, such as angled walls  92  of module  128 , or with other types of straight or angled walls. Finally, it will be understood by those skilled in the art that the shape of bubble traps  92  and/or  294  can be varied in other manners from those shown in  FIGS. 8-11 . 
         [0064]    Various other alterations and changes can be made to the foregoing embodiments without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. This disclosure is presented for illustrative purposes and should not be interpreted as an exhaustive description of all embodiments of the invention or to limit the scope of the claims to the specific elements illustrated or described in connection with these embodiments. For example, and without limitation, any individual element(s) of the described invention may be replaced by alternative elements that provide substantially similar functionality or otherwise provide adequate operation. This includes, for example, presently known alternative elements, such as those that might be currently known to one skilled in the art, and alternative elements that may be developed in the future, such as those that one skilled in the art might, upon development, recognize as an alternative. Further, the disclosed embodiments include a plurality of features that are described in concert and that might cooperatively provide a collection of benefits. The present invention is not limited to only those embodiments that include all of these features or that provide all of the stated benefits, except to the extent otherwise expressly set forth in the issued claims. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular. Still further, any references to “first” and “second,” or other numerical designations, should not be construed as excluding additional elements that may be added beyond those specifically identified by number.