Patent Abstract:
An external portion of an auditory prosthesis includes magnets, electronics, and other components. In bone conduction auditory prostheses, reducing the amount of mass subject to vibrations in an auditory prosthesis has a positive effect on tuning of the device. One way of reducing such mass is to resiliently more massive components within the auditory prosthesis housing. Such resilient mounting reduces the dampening effect that these massive components have on vibrations generated by the prosthesis. When electronic components are suspended, feedback to said components is also reduced, resulting improved performance.

Full Description:
BACKGROUND 
       [0001]    An auditory prosthesis can be placed on the skull of a recipient to deliver a stimulus in the form of a vibration to the skull. These types of auditory prosthesis are generally referred to as bone conduction devices. The auditory prosthesis receives sound via a microphone located on a head-mounted processor. The head-mounted processor is secured to the head with a magnet that interacts with a magnet implanted in the head of the recipient. Processed sound signals are delivered as a vibration stimulus from the external portion to a bone anchor via the implanted magnet. The bone anchor vibrates the skull of the recipient at the appropriate frequency to generate a hearing percept. The magnets form a mass that can make tuning of the auditory prosthesis difficult, due to the dampening of vibrations by the mass. 
       SUMMARY 
       [0002]    Reducing the amount of mass subject to vibrations in an auditory prosthesis has a positive effect on tuning of the device. One way of reducing such mass is to resiliently mount magnets, electronics, and other components within the auditory prosthesis housing. Such resilient mounting reduces the dampening effect that these massive components have on vibrations generated by the prosthesis. When electronic components are suspended, feedback to said components is also reduced, resulting improved performance. 
         [0003]    This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1A  depicts a partial perspective view of a percutaneous bone conduction device worn on a recipient. 
           [0005]      FIG. 1B  is a schematic diagram of a percutaneous bone conduction device. 
           [0006]      FIG. 2  depicts a cross-sectional schematic view of a transcutaneous bone conduction device worn on a recipient. 
           [0007]      FIGS. 3A-3C  depict partial cross-sectional schematic views of external portions of transcutaneous bone conduction devices. 
           [0008]      FIG. 4  depicts a partial perspective view of a plate/mass subsystem for use in an external portion of a transcutaneous bone conduction device. 
           [0009]      FIG. 5  depicts a partial cross-sectional schematic view of an external portion of a transcutaneous bone conduction device. 
           [0010]      FIGS. 6A and 6B  depict partial cross-sectional schematic views of alternative embodiments of plate/mass subsystems for use in an external portion of transcutaneous bone conduction devices. 
           [0011]      FIG. 7  depicts spring deformation curves for springs utilized in an external portion of a transcutaneous bone conduction device. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    The technologies described herein can typically be utilized with transcutaneous bone conduction devices. Such devices utilize one or more magnets disposed in an external portion and/or implanted portion of the bone conduction device. The magnetic field of an external magnet interacts with a magnetic field of a magnet disposed in an implanted portion of the bone conduction device. The technologies described herein are also applicable to percutaneous bone conduction prostheses that utilize an anchor that penetrates the skin of the head. An external portion of the auditory prosthesis is secured to the anchor with, e.g., a snap connection. By utilizing the technologies described herein, the anchor can be manufactured in whole or in part of a magnetic material, and a mating magnetic material can be disposed in the external portion to mate with the anchor, either alone, or also in conjunction with a snap connection. Additionally, the technologies described herein contemplate a single bone conduction device that can be utilized in both percutaneous and transcutaneous applications. Such devices can include a housing containing sound processing components, microphones, and a vibration element. When used in a percutaneous application, the vibration element can be directly connected to the anchor that penetrates the skin. When used in a transcutaneous application, a module can be attached to the vibration element and then held on the skin via, e.g., the magnetic components described above. 
         [0013]      FIG. 1A  depicts a partial perspective view of a percutaneous bone conduction device  100  positioned behind outer ear  101  of the recipient and comprises a sound input element  126  to receive sound signals  107 . The sound input element  126  can be a microphone, telecoil or similar. In the present example, sound input element  126  can be located, for example, on or in bone conduction device  100 , or on a cable extending from bone conduction device  100 . Also, bone conduction device  100  comprises a digital sound processor (not shown), a vibrating electromagnetic actuator and/or various other operational components. 
         [0014]    More particularly, sound input device  126  converts received sound signals into electrical signals. These electrical signals are processed by the sound processor. The sound processor generates control signals that cause the actuator to vibrate. In other words, the actuator converts the electrical signals into mechanical force to impart vibrations to skull bone  136  of the recipient. 
         [0015]    Bone conduction device  100  further includes coupling apparatus  140  to attach bone conduction device  100  to the recipient. In the example of  FIG. 1A , coupling apparatus  140  is attached to an anchor system (not shown) implanted in the recipient. An exemplary anchor system (also referred to as a fixation system) can include a percutaneous abutment fixed to the recipient&#39;s skull bone  136 . The abutment extends from skull bone  136  through muscle  134 , fat  128  and skin  132  so that coupling apparatus  140  can be attached thereto. Such a percutaneous abutment provides an attachment location for coupling apparatus  140  that facilitates efficient transmission of mechanical force. 
         [0016]    It is noted that sound input element  126  can comprise devices other than a microphone, such as, for example, a telecoil, etc. In an exemplary embodiment, sound input element  126  can be located remote from the BTE device  100  and can take the form of a microphone or the like located on a cable or can take the form of a tube extending from the BTE device  100 , etc. Alternatively, sound input element  126  can be subcutaneously implanted in the recipient, or positioned in the recipient&#39;s ear canal or positioned within the pinna. Sound input element  126  can also be a component that receives an electronic signal indicative of sound, such as, from an external audio device. For example, sound input element  126  can receive a sound signal in the form of an electrical signal from an MP3 player or a smartphone electronically connected to sound input element  126 . 
         [0017]    The sound processing unit of the BTE device  100  processes the output of the sound input element  126 , which is typically in the form of an electrical signal. The processing unit generates control signals that cause an associated actuator to vibrate. In other words, the actuator converts the electrical signals into mechanical vibrations for delivery to the recipient&#39;s skull. These mechanical vibrations are delivered by an external portion of the auditory prosthesis  100 , as described below. 
         [0018]      FIG. 1B  is a schematic diagram of a percutaneous bone conduction device  100 . Sound  107  is received by sound input element  152 . In some arrangements, sound input element  152  is a microphone configured to receive sound  107 , and to convert sound  107  into electrical signal  154 . Alternatively, sound  107  is received by sound input element  152  as an electrical signal. As shown in  FIG. 1B , electrical signal  154  is output by sound input element  152  to electronics module  156 . Electronics module  156  is configured to convert electrical signal  154  into adjusted electrical signal  158 . As described below in more detail, electronics module  156  can include a sound processor, control electronics, transducer drive components, and a variety of other elements. 
         [0019]    As shown in  FIG. 1B , transducer or vibration element  160  receives adjusted electrical signal  158  and generates a mechanical output force in the form of vibrations that is delivered to the skull of the recipient via a coupling apparatus  140 , as described above. The coupling apparatus  140  connects to the anchor system  162 , so as to couple the anchor system  162  to bone conduction device  100 . Delivery of this output force causes motion or vibration of the recipient&#39;s skull, thereby activating the hair cells in the recipient&#39;s cochlea (not shown) via cochlea fluid motion. 
         [0020]      FIG. 1B  also illustrates power module  170 . Power module  170  provides electrical power to one or more components of bone conduction device  100 . For ease of illustration, power module  170  has been shown connected only to user interface module  168  and electronics module  156 . However, it should be appreciated that power module  170  can be used to supply power to any electrically powered circuits/components of bone conduction device  100 . 
         [0021]    User interface module  168 , which is included in bone conduction device  100 , allows the recipient to interact with bone conduction device  100 . For example, user interface module  168  can allow the recipient to adjust the volume, alter the speech processing strategies, power on/off the device, etc. In the example of  FIG. 1B , user interface module  168  communicates with electronics module  156  via signal line  164 . 
         [0022]    Bone conduction device  100  can further include external interface module that can be used to connect electronics module  156  to an external device, such as a fitting system. Using external interface module  166 , the external device, can obtain information from the bone conduction device  100  (e.g., the current parameters, data, alarms, etc.) and/or modify the parameters of the bone conduction device  100  used in processing received sounds and/or performing other functions. 
         [0023]    In the example of  FIG. 1B , sound input element  152 , electronics module  156 , vibration element  160 , power module  170 , user interface module  168 , and external interface module have been shown as integrated in a single housing, referred to as housing  150 . However, it should be appreciated that in certain examples, one or more of the illustrated components can be housed in separate or different housings. Similarly, it should also be appreciated that in such embodiments, direct connections between the various modules and devices are not necessary and that the components can communicate, for example, via wireless connections. 
         [0024]      FIG. 2  depicts an exemplary embodiment of a transcutaneous bone conduction device  200  that includes an external portion  204  and an implantable portion  206 . The transcutaneous bone conduction device  200  of  FIG. 2  is a passive transcutaneous bone conduction device in that a transducer or vibration element  208  is located in the external portion  204 . In general, the external portion  204  can include the control and sound processing components depicted above in  FIG. 1B . For clarity however, these components are generally not depicted; instead, structural elements particular to a transcutaneous bone conduction device  200  are shown. Vibration element  208  is located in housing  210  of the external component, and is coupled via a coupling apparatus  211  to the plate  212 , which can be discrete from the housing  210  as depicted, or disposed within the housing  210 . Plate  212  can be in the form of a permanent magnet and/or in another form that generates and/or is reactive to a magnetic field, or otherwise permits the establishment of magnetic attraction between the external portion  204  and the implantable portion  206  sufficient to hold the external portion  204  against the skin of the recipient. In other embodiments, magnets or magnetic materials can be discrete from plate  212 . Magnetic attraction can be further enhanced by utilization of a magnetic implantable plate  216 . In alternative embodiments, multiple magnets in both the external portion  204  and implantable portion  206  can be utilized. 
         [0025]    In an exemplary embodiment, the vibration element  208  is a device that delivers vibration stimulus to the skull of a recipient. In operation, sound input element  126  converts sound into electrical signals. Specifically, the transcutaneous bone conduction device  200  provides these electrical signals to vibration element  208 , or to a sound processor (not shown) that processes the electrical signals, and then provides those processed signals to vibration element  208 . The vibration element  208  converts the electrical signals (processed or unprocessed) into vibrations. Because vibration element  208  is mechanically coupled to plate  212 , the vibrations are transferred from the vibration element  208  to plate  212  via coupling apparatus  211 . Implantable plate assembly  214  is part of the implantable portion  206 , and can be made of a ferromagnetic material that can be in the form of a permanent magnet, that generates and/or is reactive to a magnetic field, or otherwise permits the establishment of a magnetic attraction between the external portion  204  and the implantable portion  206  sufficient to hold the external portion  204  against the skin  132  of the recipient. Accordingly, vibrations produced by the vibration element  208  of the external portion  204  are transferred from plate  212  across the skin  132  to implantable plate  216  of implantable plate assembly  214 . This can be accomplished as a result of mechanical conduction of the vibrations through the skin  132 , resulting from the external portion  204  being in direct contact with the skin  132  and/or from the magnetic field between the two plates  212 ,  216 . These vibrations are transferred without a component penetrating the skin  132 , fat  128 , or muscular  134  layers on the head. 
         [0026]    As can be seen, the implantable plate assembly  214  is substantially rigidly attached to bone fixture  220  in this embodiment. Implantable plate assembly  214  includes through hole  220  that is contoured to the outer contours of the bone fixture  218 , in this case, a bone screw that is secured to the bone  136  of the skull. This through hole  220  thus forms a bone fixture interface section that is contoured to the exposed section of the bone fixture  218 . In an exemplary embodiment, the sections are sized and dimensioned such that at least a slip fit or an interference fit exists with respect to the sections. Plate screw  222  is used to secure implantable plate assembly  214  to bone fixture  218 . As can be seen in  FIG. 2 , the head of the plate screw  222  is larger than the hole through the implantable plate assembly  214 , and thus the plate screw  222  positively retains the implantable plate assembly  214  to the bone fixture  218 . In certain embodiments, a silicon layer  224  is located between the implantable plate  216  and bone  136  of the skull. 
         [0027]    Notably, the external portion of a bone conduction auditory prosthesis can be utilized in both the percutaneous application of  FIGS. 1A and 1B , and the transcutaneous application of  FIG. 2 . For example, a bone conduction auditory prosthesis can include a housing containing, e.g., the various modules and elements depicted in  FIG. 1B . Those elements include vibration element  160  ( FIG. 1B ), which is equivalent to vibration element  208  ( FIG. 2 ). The vibration element can be connected to a coupling apparatus  140  ( FIG. 1B ) or  211  ( FIG. 2 ). Such a coupling apparatus can be connected to an anchor system  162  ( FIG. 1B ) in a percutaneous bone conduction application. Alternatively, the coupling apparatus can be connected to a plate or other transmission element  212  (FIG.  2 ) to be utilized in a transcutaneous application. This increases manufacturing efficiencies by allowing the same bone conduction device to be used in either configuration. 
         [0028]      FIGS. 3A-3C  depict partial cross-sectional schematic views of external portions  300   a - c  of transcutaneous bone conduction devices. These depicted embodiments are described generally together followed by a description of each specific embodiment. Each of the depicted embodiments includes a housing  304   a - c  that includes a vibration element, sound processing electronics, batteries, and other elements disposed therein. These elements are not depicted in the FIGS. A coupling apparatus  306   a - c  extending from the housing  304   a - c  is connected to the vibration element. The coupling apparatus  306   a - c  can be connected to a bone anchor system (in the case of a percutaneous bone conduction device) or to a transmission element  308   a - c  (in the case of a transcutaneous bone conduction device). An underside  318   a - c  of the transmission element  308   a - c  is adapted to contact the skin of a recipient. A magnet housing  302   a - c  contains one or more masses  310   a - c . Either or both of the housing  302   a - c  and the masses  310   a - c  are connected to the transmission element  308   a - c  with one or more resilient elements  312   a - c . Different types of resilient elements  312   a - c , such as coil springs, leaf springs, torsion springs, shape-memory elements, wave springs, and elastomeric elements, can be utilized in the external portions described herein. 
         [0029]    The masses  310   a - c  can be any type of material that can be utilized to help secure the external portion  300   a - c  to the skin of a patient, proximate an implanted portion of a bone conduction device. As described above, the external portion  300   a - c  is held against the skin of a recipient due to magnetic force between elements of the external portion  300   a - c  and the implanted portion. Thus, the masses  310   a - c  can be a magnetic component, such as a permanent magnet, a soft magnetic material, or other materials capable of transmitting magnetic flux, e.g., iron, nickel, cobalt, and compositions thereof. In general, utilizing permanent magnets on both an external portion  300   a - c  and an implanted portion can exhibit the strongest retention forces. However, in other embodiments, the masses  310   a - c  can be permanent magnets while a soft magnetic material can be utilized in the implanted portion. In yet another embodiment, the masses  310   a - c  can be a soft magnetic material and permanent magnets can be disposed in the implanted portion. Regardless of the type of magnetic component used, the presence of the masses  310   a - c  can display undesirable effects on the auditory performance of the auditory prosthesis. In one example, the added weight of the masses  310   a - c  can reduce the level of force transmitted through the skin by the transmission element  308   a - c  at higher frequencies. Indeed, the heavier the masses  310   a - c , the greater the force reduction. In another example, the masses  310   a - c  cause increased feedback. This feedback can be at least partially be caused by the pumping of air by the masses  310   a - c . To remedy this and other problems, resilient elements  312   a - c  flexibly connect the housing  302   a - c  and/or the masses  310   a - c  to the transmission element  308   a - c . By utilizing resilient elements  312   a - c , vibration of the masses  310   a - c  is reduced or eliminated while the transmission element delivers vibrational stimulus to the skull of a recipient. In other embodiments, the masses  310   a - c  can be incorporated into the vibration element  304   a - c . The external portions  300   a - c  are utilized in conjunction with transcutaneous bone conduction devices and are individually described in more detail below. 
         [0030]    Referring to the external portion  300   a  of  FIG. 3A , specifically, the transmission element  308   a  includes a rigid connection element  314   a  that connects to the coupling apparatus  306   a . The rigid connection element  314   a  passes through an opening  324   a  in the magnet housing  302   a , which has a substantially annular shape. The connection can be made with a screw, bolt, press-fit connection, threaded connection, adhesive, and/or other mechanical or chemical connections. In certain embodiments, the coupling apparatus  306   a  can be eliminated such that the rigid connection element  314   a  can be directly connected to the vibration element  304   a . The rigid connection element  314   a  is connected to, or integral with, a plate  316   a  that has an external surface  318   a  that is adapted to contact a skin surface of a recipient when worn. In embodiments, the masses  310   a  are disposed within a magnet housing  302   a  and are proximate an internal surface  320   a  of the plate. One or more resilient elements  312   a  connect the plate  316   a  to the magnet housing  302   a . An odd or even number of resilient elements  312   a  can be disposed so as to evenly balance the weight of the masses  310   a  about an axis A defined by the rigid connection element  314   a.    
         [0031]      FIG. 3B  depicts an external portion  300   b  having a generally similar configuration to that depicted in  FIG. 3A , thus, many of the components are not described further. In this embodiment, the magnet housing  302   b  and the masses  310   b  contained therein are disposed proximate an internal surface  320   b  of a plate  316   b . In this case, however, the magnet housing  302   b  is flexibly connected to the rigid connection element  314   b  of the transmission plate  316   b  with one or more resilient elements  312   b . An odd or even number of resilient elements  312   b  can be disposed so as to evenly balance the weight of the masses  310   b  about axis A.  FIG. 3C  depicts another embodiment of an external portion  300   c  with components generally similar to that depicted in  FIG. 3A , thus, many of the components are not described further. In this embodiment, the transmission element  308   c  is the rigid connection element  314   c , which has sufficient surface area so as to deliver a vibration stimulus to the skull of a recipient via the external surface  318   c . Here, as in  FIG. 3B , the magnet housing  302   c  is flexibly connected to the rigid connection element  314   c  with one or more resilient elements  312   a . An odd or even number of resilient elements  312   c  can be disposed so as to evenly balance the weight of the masses  310   c  about the axis A. 
         [0032]      FIG. 4  depicts a partial perspective view of a plate/mass subsystem  400  for use in an external portion of a transcutaneous bone conduction device such as described herein. As described above, an external portion of a bone conduction device can be utilized for both percutaneous and transcutaneous applications. The plate/mass subsystem  400  depicted in  FIG. 4  can be connected to the coupling apparatus of the external portion so as to enable the external portion to be utilized in a transcutaneous application. The plate/mass subsystem  400  includes a mass  402  that, in the depicted embodiment, includes a magnet housing  404  having one or more magnets  406  disposed therein. Other materials, such as those described above, can be used in place of the magnets  406 . Although two magnets  406  are depicted, other numbers of magnets can be utilized, although it is advantageous to position the magnets about the magnet housing  404  so as to balance the forces attendant therewith. 
         [0033]    The mass  402  is connected to a transmission element  408  via a number of resilient members  410 , such that a bottom surface  412  of the mass  402  is spaced apart from a top surface  414  of the transmission element  408 , which in this embodiment is a plate. A rigid connection element  416  such as a shaft is connected to or integral with a central portion of the transmission element  408 . The rigid connection element  416  penetrates a central opening or through-hole  418  defined by both a top surface and a bottom surface of the mass  402 , so as to not contact the mass  402 . Since the mass  402  is connected to the transmission element  408  with resilient members  410 , contact between the connection element  408  and the mass  402  would cause vibrations to be transmitted to the mass  402 , thus defeating one of the purposes of the proposed configuration. The rigid connection element  416  includes an interface  420  for releasably securing the rigid connection element  416  to a coupling apparatus of a vibration element, as described above. The interface  420  can be a shaft, a threaded rod, a screw, a bolt, or other connection structure that allows the plate/mass subsystem  400  to be connected to the vibration element of an external portion of an auditory prosthesis. Once secured, the complete external portion can be placed on the head and used as a transcutaneous bone conduction auditory prosthesis. The magnets  406  magnetically couple with one or more implanted magnets proximate the skull of a recipient. 
         [0034]      FIG. 5  depicts a partial cross-sectional schematic view of another embodiment of an external portion  500  of a transcutaneous bone conduction device. The external portion  500  includes a housing  502  in which is disposed a vibration element  504 . The vibration element  504  is connected directly to a transmission element  508  without, e.g., a coupling apparatus such as described above. Thus, the external portion  500  of  FIG. 5  is utilized in a dedicated transcutaneous bone conduction application, unlike certain of the previous embodiments that can be interchanged between transcutaneous and percutaneous applications. In the depicted embodiment, the transmission element  508  includes a shaft  514  connected to or integral with a plate  516 . As in the previous embodiments, the plate  516  has a lower surface  518  adapted to contact the skin of a recipient, as well as an upper surface  520 . Resilient members  512  flexibly connect the upper surface  520  to one or more masses  510 . The external portion  500  also includes a number of additional components  524  required for the functionality of the external portion  500 . These are described generally above and can include a battery, electronics, wireless communication devices, sound input elements such as microphones, and so on. To further reduce feedback, the components  524  can be connected to the masses  510  at interface  526 . In such an embodiment, the housing  502  can be connected to the transmission element  508  such that vibrations generated by the vibration element  504  are dissipated into the housing  502 , while the components  524  are isolated from vibration via the resilient elements  512 . In another embodiment, the components  524  can be connected to the housing  502  at interface  528 . In such an embodiment, the vibration element  504  and/or transmission element  508  can be connected to the housing via a flexible or resilient connection, not shown. 
         [0035]      FIGS. 6A and 6B  depict partial cross-sectional schematic views of alternative embodiments of plate/mass subsystems  600  for use in an external portion of transcutaneous bone conduction devices. The plate/mass subsystems  600  of both  FIGS. 6A and 6B  are described together. Each plate/mass subsystem  600  includes a transmission element  608  having a form factor in the shape of a plate, although other configurations are contemplated. A rigid connection element  616  extends from the transmission element  608  and includes an interface  620  can be a shaft, a threaded rod, a screw, a bolt, or other connection structure that allows the plate/mass subsystem  600  to be connected to the vibration element of an external portion of an auditory prosthesis. Masses  606  can be magnetic components such as described above. In  FIG. 6A , the masses  606  include one or more arms  630  that can extend from the mass  606 . The arm  630  provides a point of connection for a resilient element  610  that connects the mass  606  to the transmission element  608 . Similarly the masses  606  of  FIG. 6B  can define bores  632  therein. One or more resilient elements  610  can be disposed in the bores  632  to resiliently connect the masses  606  to the transmission element  608 . Contrasted with the embodiments described above where the resilient elements are connected to a lower surface of a mass, the configurations depicted in  FIGS. 6A and 6B  connect the resilient elements  610  proximate an upper portion of the masses  606 . This can also allow for use of smaller masses  606  than might otherwise be utilized in the embodiments where resilient elements are connected to the underside of the mass (for example, as depicted in  FIG. 3A ). 
         [0036]      FIG. 7  depicts spring deformation curves for springs utilized in an external portion of a transcutaneous bone conduction device. Again, different types of resilient elements, such as coil springs, leaf springs, torsion springs, shape-memory elements, wave springs, and elastomeric elements, can be utilized in the external portions described herein.  FIG. 7  depicts curves for springs with linear characteristics, degressive characteristics, and progressive characteristics, each of which can be utilized in conjunction with the embodiments described herein. The label W depicts work performed in the spring. In certain embodiments, a degressive spring can be desirable, as it will minimize the required length of compression from the static magnetic attraction force (e.g., the force generated by attraction to an implanted portion of an auditory prosthesis and an associated magnet). Such a degressive spring is non-linear with respect to force and length and still allows for a low spring constant (e.g., a weak spring) in the working range, which allows for a low decoupling frequency. 
         [0037]    This disclosure described some embodiments of the present technology with reference to the accompanying drawings, in which only some of the possible embodiments were shown. Other aspects, however, can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments were provided so that this disclosure was thorough and complete and fully conveyed the scope of the possible embodiments to those skilled in the art. 
         [0038]    Although specific embodiments were described herein, the scope of the technology is not limited to those specific embodiments. One skilled in the art will recognize other embodiments or improvements that are within the scope of the present technology. Therefore, the specific structure, acts, or media are disclosed only as illustrative embodiments. The scope of the technology is defined by the following claims and any equivalents therein.

Technology Classification (CPC): 0