Abstract:
A multi-use, hand held, single patient oscillatory positive expiratory pressure respiratory therapy device which is easily assembled and disassembled for cleaning, and which is not position dependent during therapy, but operable through a wide range of device orientation.

Description:
This application is a continuation in part of application Ser. No. 09/449,208 filed Nov. 24, 1999, which is now U.S. Pat. No. 6,581,598. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates in general to a hand-held, multi-use, single patient positive oscillatory expiratory pressure respiratory therapy device and, in particular, to an easily assembled and disassembled positive oscillatory expiratory pressure respiratory therapy device which is not position dependent during therapy, but operable through a wide range of device orientation. 
   2. Description of Related Art 
   Persons who suffer from mucus-producing respiratory conditions that result in large amounts of mucus being produced in the lungs often require assistance in the removal of these secretions. If these secretions are allowed to remain in the lungs, airway obstruction occurs resulting in poor oxygenation and possible pneumonia and/or death. One of the clinically recognized treatments for this condition is a technique known as positive expiratory pressure therapy or PEP. With PEP therapy, a patient exhales against a resistance to generate expiratory pressure at a substantially constant rate of flow. Prescribed expiratory pressures are generally in the range of 10–20 cm of H 2 0, although other pressure ranges and pressures can be used, with a preferred flow rate of between 10–25 liters per minute. 
   In the use of PEP therapy, a patient breaths through an orifice restricter to generate a positive pressure in the lungs during exhalation, with the pressure falling to zero at the end of the exhalation. By selection of the proper-sized orifice, a given pressure is determined for the exhalation flow rate generated by an individual patient. This extended, substantially constant, flow of elevated-pressure exhalation has been shown to be effective for moving secretions trapped in the lungs to the larger airways where the secretions can then be removed through coughing. It has also been found that in the treatment of patients having chronic obstructive pulmonary disease (COPD), chronic bronchitis, cystic fibrosis, atelectasis, or other conditions producing retained secretions, treatment with PEP therapy is improved by combining positive expiratory pressure therapy with airway oscillation and intermittent air-flow acceleration. To this end a hand-held, single patient multi-use, positive expiratory pressure respiratory therapy device was developed by assignees of the present invention, and is the subject matter of a co-pending application, Ser. No. 09/449,208, filed Nov. 24, 1999 for “POSITIVE EXPIRATORY PRESSURE DEVICE”. 
   The present invention comprises a positive oscillatory expiratory pressure respiratory therapy device which is easily assembled and disassembled for the purpose of cleaning, and is not position dependent for operation during PEP therapy. In addition, the translucency of the device housing permits inspection of the interior to insure that condensate is not being retained in the device, and the device construction is such that any condensate forming in the device may be easily removed. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to overcoming one or more of the problems or disadvantages associated with the relevant technology. As will be more readily understood and fully appreciated from the following detailed descriptions of preferred embodiments, the present invention is embodied in a positive oscillatory expiratory air pressure respiratory therapy device which is easily assembled and disassembled for cleaning and not position dependent for operation. 

   
     DESCRIPTION OF THE DRAWINGS 
     Further objectives of the invention, together with additional features contributing thereto and advantages accruing therefrom, will be apparent from the following description of preferred embodiments of the invention which are shown in the accompanying drawings with like reference numerals indicating corresponding parts throughout, wherein: 
       FIG. 1  is a perspective view of a first embodiment of the assembled invention; 
       FIG. 2  is an exploded perspective view of the invention illustrated in  FIG. 1  with portions removed to better illustrate the internal structure thereof; 
       FIGS. 3 ,  4 ,  5  and  6  are, respectively, an upper and lower perspective view, top elevation and sectional view of the platform portion of the invention to better illustrate a portion of the structure forming the non-linear orifice; 
       FIG. 7  is a perspective view of the rocker and platform portions of the invention as they are installed onto the lower portion of the device housing for producing an oscillatory positive expiratory air pressure; 
       FIG. 8  is a perspective view of the assembled device with the upper portion of the device open to better illustrate a portion of the structure for adjusting the magnitude and frequency of the oscillatory positive expiratory air pressure and the ease in which the device may be assembled and disassembled for cleaning; 
       FIG. 9  is a top elevation view of the assembled device; 
       FIG. 10  is a sectional view of the device as illustrated in  FIG. 9  taken along lines  10 — 10  to better illustrate the internal structure for creating the oscillatory positive expiratory air pressure and to control the oscillatory frequency and pressure, and the manner in which the magnitude and frequency of the oscillations can be adjusted; 
       FIG. 11  is a rear perspective view of an adjustment dial portion of the invention to better illustrate the manner in which the platform portion illustrated in  FIGS. 3–6  is positionable relative to the rocker portion illustrated in  FIG. 2  to determine the magnitude and frequency of the oscillations; 
       FIG. 12  is a planar view of the adjustment dial illustrated in  FIG. 11  to better illustrate the structure and function thereof; 
       FIG. 13  is a mechanical schematic of a second embodiment of the invention utilizing dual rocker and platform assemblies to generate an oscillatory positive expiratory air pressure; 
       FIG. 14  is a mechanical schematic of a third embodiment of the invention utilizing the platform and rocker assembly as illustrated herein, but without a magnet control to generate an oscillatory positive expiratory air pressure; and 
       FIG. 15  is a mechanical schematic of a fourth embodiment of the invention utilizing a spring-biased air-flow closure to generate an oscillatory positive expiratory air pressure. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to the drawings, there is illustrated in  FIGS. 1 and 2  an oscillatory positive expiratory pressure (PEP) respiratory therapy device  1000  for applying oscillatory positive expiratory air pressure (PEP) therapy to a patient. When expiratory air is passed from a patient through an air-flow tube  200  to an expiratory-air-driven oscillatory rocker assembly  400  contained within a two-part housing  300 , the expiratory-air-driven oscillatory rocker assembly  400  creates an oscillatory positive expiratory air pressure which is applied to the patient during exhalation. The expiratory-air-driven oscillatory rocker assembly  400  comprises two portions, a rocker portion  440  and a rocker support or platform portion  480  which act together in creating the oscillatory PEP therapy and are best illustrated in  FIGS. 2–10 . The details of the structure and operation of this oscillatory PEP portion of the device will be described in detail hereinafter. 
   To control the magnitude and frequency of the oscillatory pressure applied to a patient, a rotatable frequency control dial  350  is carried by and positioned at the discharge end of an air-flow tube  200 . The air-flow tube  200  is carried by a lower housing portion  302 , and supports the rocker assembly  400 . By operation of the adjustable frequency control dial  350  in a manner to be hereinafter described, the relative positioning between the oscillatory PEP inducing portions of the oscillatory rocker assembly  400 , the rocker portion  440  and the rocker support portion  480 , is adjusted to control the magnitude and frequency of the oscillatory expiratory air pressure. 
   The expiratory-air-driven oscillatory rocker portion  440  is best illustrated in the exploded view of  FIG. 2 , and  FIGS. 7 ,  8  and  10 . The rocker support portion  480 , which functions in cooperation with the rocker portion  440  to produce an oscillatory expiratory air flow and pressure, is also illustrated in the exploded view of  FIG. 2 , and in more detail in  FIGS. 3 through 6  and  10 . The expiratory-air-driven oscillatory rocker portion  440  and the rocker support portion  480 , when assembled together, form the rocker assembly  400 . 
   The rocker assembly  400  is supported on the air-flow tube  200  which comprises a sealed chamber from a patient input end  201  to a discharge opening  203  which is periodically closed to create the oscillatory PEP treatment. In this manner, the rocker assembly  400  functions to create an oscillatory positive expiratory air pressure and flow rate in response to a patient&#39;s exhalation, and the patient&#39;s expiratory air is thereby directed to and through the rocker assembly  400 . 
   As best shown in  FIGS. 2 ,  7  and  10 , there is illustrated the air-flow tube  200  having a first or patient input end  201  for receiving a standard  22  mm mouthpiece  202  into which a patient discharges expiratory air. The air passed into the air-flow tube through the input  201  passes out of the air-flow tube  200  through a discharge opening  203 , and is applied to the rocker assembly  400 . The air-flow tube discharge opening  203  is formed in the top flat planar surface  205  of the air-flow tube  200  and the expiratory air passed there through is applied to the oscillatory rocker assembly  400  for creating the oscillatory PEP therapy for the patient in a manner to be hereinafter described in detail. 
   While a second opposite end of the air-flow tube could be closed, for convenience of use, the opposite end  204  is open and carries a conventional one-way flapper valve  225 . The flapper valve  225  allows a patient to draw inspiratory air into the air-flow tube  200  through the opening  204 , but prevents expiratory air from being passed out of the air-flow tube  200  through the opening  204 . To this end the one-way flapper valve  225  is positioned on a spider  206  which is inserted into the opening  204  against a shoulder forming a space sufficient for the one-way operation of the valve. Upon inhalation by a user, the valve  225  opens and allows air to pass into the air-flow tube  200 , and upon exhalation, the valve  225  is held closed against the spider  206  thereby preventing expiratory air from passing out through the valve  225 . If the end  204  were closed, a user would not be able to inhale through the device  1000 , but that would not effect the operation of the device in providing oscillatory PEP therapy in the manner to be described herein. 
   After the expiratory air is applied to the rocker assembly  400 , the air thereafter exits from the device  1000  through openings in the rotatable adjusting dial  350  carried in the housing  300 . 
   As best illustrated in  FIGS. 2 ,  7 ,  8  and  10 , the rocker portion  440  is balanced for pivotal movement about pivot pins  441  on spaced pivot supports  481  formed on a platform  485  of the rocker support portion  480 . The pivot pins  441  form a transverse pivot axis for the rocker portion  440  which lies in a plane above and extends transverse to the longitudinal axis of the platform  485 . The pivot pins  441  are limited in their axial and vertical movement by a pair of locking guides  482 , carried by the platform  485 , one of which is positioned adjacent each of the pivot supports  481  to maintain the pivot pins  441  in their proper position on the pivot supports  481 . In this manner the rocker portion  440  is pivotal relative to the rocker support portion  480  regardless of the orientation of the device  1000 , allowing the oscillatory PEP device  1000  to function regardless of its orientation in use. A balance pad  442  and balancing cylinder  443  are formed at one end of a rocker arm  445  to balance the weight of a cone-shaped air-flow closure member  447  and a pin of magnetically attractable material, such as a steel pin  448 , both of which are carried at the opposite end of the rocker arm  445 . The pin  448  is carried at the distal end of the rocker arm  445  by a plurality of gripping fingers  446  which partially encircle the pin  448  for holding the pin in a position to be exposed to the magnetic field of a disc-shaped magnet  488  carried on the air-flow tube  200  in a magnet holder  490 . 
   The cone-shaped air-flow closure member or air-flow closure cone  447  is sized and positioned on the rocker arm  445  to be periodically inserted into a tapered bell-shaped or trumpet-shaped air-discharge outlet  487  formed in the platform  485  to create the oscillatory PEP when expiratory air is discharged through the opening  203  in the air-flow tube  200 . As best illustrated in  FIGS. 3–6 , the interior of the air-discharge outlet  487  has a non-linear taper or bell-shaped interior surface to form a non-linear air discharge outlet for creating the oscillatory PEP therapy in response to the pivotal movement of the air-flow closure cone  447  in to and out therefrom. In this manner the discharge outlet  487  is periodically closed and re-opened allowing the expiratory air discharged there through to be discharged from the housing  300  through the openings in the adjusting dial  350 . 
   The oscillatory rocker assembly  400  is secured on the air-flow tube  200  and positioned within the housing  300  by means of a positioning tang  484  which extends downwardly from the platform  485  as best illustrated in  FIGS. 2 ,  4  and  6 . A pair of side walls  486  of the platform  485 , the bottoms of which rest on the planar surface of the air-flow tube  200 , are formed with a ridged finger-engaging surface to facilitate the removal and repositioning of the rocker support portion  480  relative to the air-flow tube  200  for cleaning the device  1000  as necessary. Sidewalls  209  extend vertically outward from the planar surface  205  of the air-flow tube  200  and are spaced apart a distance sufficient to receive the rocker arm  445  there between. In this manner, the rocker arm is protected between the sidewalls  209  when the upper and lower housing portions,  301  and  302 , respectively, are separated for cleaning. This positioning protects the rocker assembly  400  from being inadvertently improperly grasped by a user when disassembling the device  1000  for cleaning, and the user&#39;s attention is directed to the ribbed or ridged finger-engaging surface of the side walls  486  which are preferred for grasping when the rocker assembly is to be removed. 
   The tang  484  is secured in a channel  284  extending upwardly from the top of the planar surface  205  of the air-flow tube  200  to securely position the oscillatory rocker assembly  400  onto the air-flow tube  200 . In this manner a circular guide  489  engages with a cowling  287  of the complementary air-flow tube discharge opening  203  so that the non-linear tapered, bell-shaped discharge outlet  487  carried by the platform  485  is aligned in fluid communication with and extends into the discharge opening  203  in the air-flow tube  200 . Another tang  384  extends downwardly from the interior of upper portion  301  of the housing  300  and passes through an aperture  444  in the rocker arm  445  to press downwardly against the platform  485  thereby securing the oscillatory rocker assembly  400  in the proper position on the air-flow tube  200  when the upper  301  and lower  302  portions of the housing  300  are engaged. 
   The upper and lower portions of the housing,  301  and  302 , respectively, are pivotally connected to facilitate the opening and closing of the housing such as when it is desired to clean the interior thereof. To this end, as best illustrated in  FIGS. 2 and 8 , the upper housing  301  is formed with a pair of tabs  303  for engaging a pair of complementary pivot pins  306  formed on the lower housing  302  in a position to engage the tabs  303  to form a pivotal connection therewith. A plurality of pins  307  extend outwardly from the upper housing  301  to engage complementary receptacles  308  formed on the lower housing  302  to maintain the two portions of the housing closed unless it is desired that they be opened for access to the interior of the housing  300 . When it is desired to open the housing  300 , the sides of the upper housing portion  301  are compressed towards each other to facilitate releasing the pins  307  from the receptacles  308 . When the pins  307  are so positioned, the two housing portions  301  and  302  are enabled to be pivoted relative to each other about the pivot connection  303 ,  306  providing access to the interior of the housing  300  and the components enclosed therein. A securing tab  305  extends outwardly from the end of the upper housing  301  opposite to the tabs  303  to engage a complementary recess formed in the lower housing  302  to facilitate securing the two housing portions  301 ,  302  of the housing  300  together and the mouthpiece  202  is passed over the tab  305  when place onto the end  201  of the air-flow tube  200 . 
   To create the periodically interrupted discharge of expiratory air for applying the oscillatory PEP therapy to a patient, the magnetically attractable material or steel pin  448  is carried on the pivotal rocker arm  445  at a position in operative proximity to the magnet  488  carried by the rocker support portion  480 . While the rocker assembly  400  may be constructed without magnetically attractable material and a magnet/magnet holder, the device  1000  will still provide oscillatory PEP therapy. The use of the magnetic material and magnet/magnet holder permits the device  1000  to control the magnitude and frequency of the oscillations. 
   The magnet  488  is carried in a magnet holder  490  having a receiver portion or pocket  491  formed in a circular configuration for receiving the disc-shaped magnet  488 , and has a plurality of gripping or centering fingers  492  for retaining the magnet  488  in the circular-shaped receiver pocket. The receiver pocket  491  is formed at one end of a vertically positionable carrier  495 , which is guided in its vertical movement by a pair of guide rails  210  extending outwardly from the flat planar surface  205  of the air-flow tube  200 . The opposite end of the carrier  495  extends vertically upward from a position adjacent to the circular-shaped receiver pocket  491  and terminates in a follower tip  496  which engages a cam surface  396  formed in the oscillation frequency control dial  350 , as illustrated in  FIGS. 7 ,  8  and  11 . 
   In this manner, rotation of the frequency control dial  350  will move the follower tip  496  causing the carrier  495  to move vertically between the guide rails  210 . Raising or lowering the carrier  495  moves the magnet  488  towards or away from the steel pin  448  to vary the magnetic attractive force there between. Rotation of the frequency control dial  350  controls the frequency of the oscillations by which the PEP treatment or therapy is applied in accordance with the desires of the healthcare provider. While the device  1000  will function to provide an oscillatory PEP pulse without the use of the magnetic field between the magnet  488  and the steel pin  448 , because of the opening and closing of the tapered non-linear discharge outlet  487  due to the movement of the tapered cone-shaped air-flow closure  447  induced in response to the patient&#39;s discharge of expiratory air, the use of the magnetic field permits the device  1000  to provide an adjustable range in the pressure of the patient&#39;s expiratory air discharge required to create the oscillatory positive expiratory pressure pulses. 
   To assist a patient or the healthcare provider in using the device  1000  once the proper magnetic field has been set, a plurality of indicia  310  are spaced along the control dial  350  and the top of the upper portion  301  of the housing  300 . These indicia  310 , in combination with a base reference point  360  on the upper housing  301 , are used to ensure that the correct setting is being maintained after the healthcare provider has established the desired level for treatment. To minimize the occurrence of the rotatable adjusting dial  350  being unknowingly rotated, as best illustrated in  FIG. 2  a series of tooth-like projections  211  are formed on the air-flow tube  200 . These projections are engaged by a mating tooth  351  formed on a thin chord  352  of plastic material from which the adjusting dial  350  is constructed, and which extends across the lower internal portion of the adjusting dial to form a sounding board. In this manner, when the rotatable adjusting dial  350  is turned, the tooth-like projections  211  and the mating tooth  351  provide resistance to movement and produce a mechanically generated audible sound to signal that a change in position has occurred. A pair of stops  354  are formed on the interior of the adjusting dial  350 , best illustrated in  FIGS. 11 and 12 , which in combination with a side portion  309  of the lower housing  302 , limit the rotational movement of the dial  350  relative to the housing  300 . 
   The rotatable adjusting dial  350  is rotatably mounted on the end of the air-flow tube  200  adjacent to the end  204  thereof, and is held in contact by a snap fit therewith and guides  355  which provide three point contact between the dial  350  and the end of the air-flow tube. As expiratory air is passed through the rocker assembly  400  the air will freely flow from the housing  300  through the spaces between the housing  300  and the adjusting dial  350 . 
   Referring now to the embodiments illustrated in  FIGS. 13 and 14 , there are illustrated two additional embodiments of the invention utilizing a rocker assembly  400  carried on an air-flow tube  200 . In the embodiment illustrated in  FIG. 13 , two cone-shaped air-flow closure members or air-flow closure cones  447  are utilized supported, one at each end, on a rocker arm  445   a  pivotally mounted at the approximate center thereof for mutually exclusively closing and opening one of a pair of complementary tapered bell-shaped or trumpet-shaped air-discharge outlets  487  formed in the air-flow tube  200  carried within a housing  300 , not shown in this illustration. As shown in this Fig. the end  204  of the air-flow tube is closed, but could be formed with a one-way valve  225  as previously described. In this embodiment it is believed that the flow of air out of one of the air-discharge outlets  487  will cause the complementary air-flow closure cone  447  to be accelerated downwardly increasing the pressure in the air-flow tube such that the other air-flow closure cone  447  will be forced upwardly from its associated air-discharge outlet  487  until the flow of expiratory air through the outlet  487  and over the combination of the conical surface of the air-flow closure cone  487  and the tapered non-linear orifice of the air-discharge outlet  487  will cause the cone  447  to be accelerated downwardly towards the outlet  487  repeating the cycle and generating an oscillatory expiratory air pulse to the user as the two discharge outlets are cycled on and off. 
   The embodiment illustrated in  FIG. 14  is similar to the embodiment described herein without the magnetic  488  and magnet carrier  495 . In this embodiment there would be no oscillatory frequency control and, therefore, no need for a frequency adjusting dial  350 . The unit would not be operable in all orientations, but would still provide oscillatory PEP therapy at a fixed frequency which would be dependent upon the weight of the rocker assembly components. 
   In the embodiment illustrated in  FIG. 15 , the air-flow tube  200  has an open end  204  through which expiratory air passes after passing through a modified air-flow closure cone  447  and associated air-discharge outlet  487 . The air-flow closure cone  447  is mounted on a spring-loaded shaft  447   b  which is adjustable to vary the force which is applied to hold the air-flow closure cone  447  against the expiratory air pressure applied through the associated air-discharge outlet  487 . When the expiratory air pressure increases above the spring force applied to the air-flow closure cone  447 , the expiratory air will be discharged through the associated air-discharge outlet functioning in the manner here to fore described and causing an oscillatory PEP to be applied to the user. 
   INDUSTRIAL APPLICABILITY 
   During use of the variable frequency or oscillatory PEP device  1000  a patient&#39;s expiratory air is delivered through the input end  201  of the air-flow tube  200  and passes through the opening  203  to the oscillatory rocker assembly  400 . Accordingly, the expiratory air pressure is applied against the cone-shaped closure  447  of the rocker assembly  400  which forms a closure of the non-linear discharge opening or orifice  487 . The pressure of the patient&#39;s expiratory air will raise the cone-shaped closure  447 , causing the rocker portion  440  to pivot about the pivot pins  441  against the force of the magnetic field between the magnet  488  carried on the pivotal rocker support portion  480  and the steel pin  448  carried on the rocker assembly  400 . As the cone-shaped closure  447  moves upwardly in response to the increasing expiratory air pressure, the constant taper of the conical shape in conjunction with the bell-shaped non-linear taper of the non-linear discharge opening or orifice  487  increases the effective discharge area thereby decreasing the air pressure applied against the cone-shaped closure  447  and reducing the upward acceleration of the rocker arm  445 . 
   When the magnetic force and the Coanda effect of the air flow over the bell-shaped or non-linear tapered interior of the discharge outlet  487  overcome the expiratory air pressure applied to the tapered cone-shaped closure  447 , the closure  447  will again begin to move downwardly and accelerate into the bell-shaped non-linear-tapered discharge orifice  487 . As the cone descends into the air flow path through the discharge outlet or orifice  487 , the annular flow area diminishes reducing the airflow rate and increasing the air pressure. This continues until the downward momentum is overcome and the cone  447  resumes its upward acceleration. Maximum pressure is obtained at this point and another cycle begins. 
   While this invention has been described in the specification and illustrated in the drawings with reference to preferred embodiments, the structures of which have been disclosed herein, it will be understood by those skilled in the art to which this invention pertains that various changes may be made and equivalents may be substituted for elements of the invention without departing from the scope of the claims. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed in the specification and shown in the drawings as the best modes presently known by the inventors for carrying out this invention nor confined to the details set forth, but that the invention will include all embodiments modifications and changes as may come within the scope of the following claims: