Patent Publication Number: US-2019170135-A1

Title: Diaphragm assembly including puller with retaining ledge

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application relates to and claims the benefit of and priority to U.S. Provisional Patent Application No. 62/594,668, entitled IMPROVED COMPONENT ASSEMBLY FOR PUMPING SYSTEM, filed Dec. 5, 2017, the entire disclosure of which is hereby wholly incorporated by reference. 
    
    
     STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
     Not Applicable 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates generally to improved components of a pumping system. More particularly, the disclosure relates to an improved diaphragm assembly for a pumping system. 
     2. Related Art 
     Certain pumping systems, such as breast pumps and wound therapy pumps, have vacuum generating assemblies within a vacuum chamber of the pumping system. Such systems can include complex connections between components to meet product life requirements, which also add cost to the device. As illustrated in  FIGS. 1 and 2 , an example of a known assembly for a diaphragm assembly  10  for a pump system can include a diaphragm  12  over-molded upon a puller  14 , and a flexible cap  16  supporting back motion of the diaphragm  12  in conjunction with a retaining bar or spring pin  18 . The retaining bar or spring pin  18  is disposed through an aperture  20  of the puller  14 . Certain components of such a system are illustrated, for example, in FIG. 9 of U.S. Pat. No. 6,997,897, incorporated herein by reference in the entirety. The diaphragm  12  includes a front face  22  and a back face  24 . The diaphragm assembly  10  maintains all actuating components for actuating the diaphragm assembly  10 , such as the puller  14 , and a cam  26  operatively connected thereto on a back face  24  of the diaphragm  12 , such that none of the actuating components of the diaphragm assembly  10  are visible along the front face  22  of the diaphragm  12  once assembled. However, costs and manufacturing complexities arise from the over-molding process, and additional components are required to manufacture and assemble such a diaphragm assembly  10 . 
     In view of the foregoing, there is a need in the art for an improved diaphragm assembly in comparison to the prior art. 
     BRIEF SUMMARY 
     In accordance with one embodiment, there is provided a diaphragm assembly. The diaphragm assembly includes a flexible diaphragm and a puller. The flexible diaphragm has a front face and an opposing back face, and a top opening formed through the diaphragm and a bottom opening. The puller has a diaphragm end, a cam end, a puller body extending between the diaphragm end and the cam end along a puller longitudinal axis, and a first retaining ledge extending laterally from the puller body with respect to the puller longitudinal axis. The puller body is disposed through the top opening with the diaphragm disposed between the diaphragm end and the first retaining ledge and with the diaphragm end disposed adjacent the front face and the first retaining ledge disposed adjacent the back face. 
     According to various embodiments, the diaphragm assembly may further include a cap having a cap central opening concentrically disposed adjacent the top opening at the back face. The puller body is disposed through the cap central opening. The first retaining ledge may include a cap engagement surface facing the diaphragm end. The cap engagement surface may be engaged with the cap with the cap disposed between the cap engagement surface and the back face of the diaphragm. The cap may have a stiffness greater than a stiffness of the diaphragm. The cap may be flexible. The diaphragm may be compressed between the first retaining ledge and the diaphragm end. The puller may be snap-fit through the top opening of the diaphragm with the first retaining ledge engaged with the cap. The diaphragm assembly may further include a cap ring concentrically disposed about the cap with the cap disposed between the cap ring and the first retaining ledge of the puller. The puller may further include a second retaining ledge extending laterally from the puller body and opposite the first retaining ledge with respect to the puller longitudinal axis. The puller may be snap-fit through the diaphragm with the second retaining ledge engaged with the cap. The first retaining ledge may have a tapered surface that is laterally more distant from the puller longitudinal axis in a direction from the cam end toward the diaphragm end. The puller may further include a second retaining ledge extending laterally from the puller body and opposite the first retaining ledge with respect to the puller longitudinal axis. The first retaining ledge and the puller body may be integrally formed of a single contiguous piece of material. The diaphragm assembly may further include a cam rotatably attached to the puller adjacent the cam end. 
     According to another aspect of the present invention, there is provided a method of assembly of a diaphragm assembly. The method includes providing a flexible diaphragm having a front face and an opposing back face. The flexible diaphragm further has a top opening formed through the diaphragm and a bottom opening. The method further includes providing a puller. The puller has a diaphragm end, a cam end, and a puller body extending between the diaphragm end and the cam end along a puller longitudinal axis. The puller further has a first retaining ledge extending laterally from the puller body with respect to the puller longitudinal axis. The method further includes inserting the cam end through the top opening from the front face of the diaphragm until the first retaining ledge of the puller is disposed at the back face of the diaphragm. 
     According to various embodiments, the method of assembly may further include compressing the diaphragm between the first retaining ledge and the diaphragm end. The method of assembly may further include providing a cap having a cap central opening concentrically disposed adjacent the top opening at the back face. The inserting of the cam end may further include inserting the cam end through the cap central opening until the first retaining ledge engages the cap with the cap and the diaphragm disposed between the diaphragm end and the first retaining ledge. The method of assembly may further include attaching a cap ring concentrically disposed about the cap with the cap disposed between the cap ring and the first retaining ledge. The cap ring may be over-molded upon the cap. 
     The present invention will be best understood by reference to the following detailed description when read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which: 
         FIG. 1  is a bottom perspective view of a prior art diaphragm assembly; 
         FIG. 2  is a bottom view of the prior art diaphragm assembly of  FIG. 1 ; 
         FIG. 3  is a bottom perspective view of the diaphragm assembly according to an aspect of the present invention; 
         FIG. 4  is a bottom view of the diaphragm assembly of  FIG. 3 ; 
         FIG. 5  is a left side view of the diaphragm assembly of  FIG. 3 ; 
         FIG. 6  is a right side view of the diaphragm assembly of  FIG. 3 ; 
         FIG. 7  is a front view of the diaphragm assembly of  FIG. 3 ; 
         FIG. 8  is a back view of the diaphragm assembly of  FIG. 3 ; 
         FIG. 9  is a top view of the diaphragm assembly of  FIG. 3 ; 
         FIG. 10  is a bottom view the diaphragm of  FIG. 9 ; 
         FIG. 11  is a cross sectional side view of the diaphragm as depicted along axis  11 - 11  of  FIG. 10 ; 
         FIG. 12  is a cross sectional side view of the diaphragm assembly as depicted along axis  12 - 12  of  FIG. 5 ; 
         FIG. 13  is an exploded view of the diaphragm assembly of  FIG. 12 ; and 
         FIG. 14  is a symbolic schematic diagram of the diaphragm assembly with a pump system and a drive mechanism. 
     
    
    
     Common reference numerals are used throughout the drawings and the detailed description to indicate the same elements. 
     DETAILED DESCRIPTION 
     The detailed description set forth below in connection with the appended drawings is intended as a description of certain embodiments of the present disclosure, and is not intended to represent the only forms that may be developed or utilized. The description sets forth the various functions in connection with the illustrated embodiments, but it is to be understood, however, that the same or equivalent functions may be accomplished by different embodiments that are also intended to be encompassed within the scope of the present disclosure. It is further understood that the use of relational terms such as top and bottom, first and second, and the like are used solely to distinguish one entity from another without necessarily requiring or implying any actual such relationship or order between such entities. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments. 
     Referring now to  FIG. 3 , there is depicted a bottom perspective view of a diaphragm assembly  28  according to an aspect of the present invention.  FIGS. 4-8  are respectively bottom, left side, right side, front and back views of the diaphragm assembly  28 .  FIGS. 9 and 10  are respectively top and bottom views of a diaphragm  30  of the diaphragm assembly  28 .  FIG. 11  is a cross sectional side view of the diaphragm  30  as depicted along axis  11 - 11  of  FIG. 10 , and  FIG. 12  is a cross sectional side view of the diaphragm assembly  28  as depicted along axis  12 - 12  of  FIG. 5 .  FIG. 13  is an exploded view of the diaphragm assembly  28  of  FIG. 12 . 
     According to an embodiment of the invention, there is provided the diaphragm assembly  28 . The diaphragm assembly  28  includes the flexible diaphragm  30  and a puller  32 . The flexible diaphragm  30  has a front face  34  and an opposing back face  36 , and a top opening  38  formed through the diaphragm  30  and a bottom opening  40 . The puller  32  has a diaphragm end  42 , a cam end  44 , and a puller body  46  extending between the diaphragm end  42  and the cam end  44  along a puller longitudinal axis  48 . Importantly, the puller  32  includes a first retaining ledge  50  extending laterally from the puller body  46  with respect to the puller longitudinal axis  48 . The puller body  46  is disposed through the top opening  38  of the diaphragm  30  with the diaphragm  30  disposed between the diaphragm end  42  and the first retaining ledge  50  and with the diaphragm end  42  disposed adjacent the front face  34  of the diaphragm  30  and the first retaining ledge  50  disposed adjacent the back face  36  of the diaphragm  30 . As will be discussed further below, the foregoing diaphragm assembly  28  facilitates an improved design that may eliminate or mitigate costs and complexities over prior art designs, such as depicted in  FIGS. 1 and 2  and reduces the number of components required to form a suitable diaphragm assembly. 
     According to various embodiments, the diaphragm assembly  28  may further include a cap  52  having a cap central opening  54  (as best viewed in  FIG. 13 ) concentrically disposed adjacent the top opening  38  at the back face  36 . The puller body  46  is disposed through the cap central opening  54 . The first retaining ledge  50  may include a cap engagement surface  58  (as best viewed in  FIG. 13 ) facing the diaphragm end  42 . The cap engagement surface  56  of the puller  32  may be engaged with the cap  52 , with the cap  52  disposed between the cap engagement surface  56  and the back face  36  of the diaphragm  30 . The cap  52  may have a stiffness greater than a stiffness of the diaphragm  30 , although the cap  52  may be somewhat flexible. The puller  32  may be snap-fit through the top opening  38  and the cap  52  with the first retaining ledge  50  engaged with the cap  52 . With the foregoing configuration, the diaphragm  30  may be compressed between the first retaining ledge  50  and the diaphragm end  42 . Such compression is used to provide a vacuum seal between the cap end  44  of the puller  32  and the diaphragm  30 . In this regard, an aspect of the present invention is that the puller  32  may be attached to the diaphragm  30  in sealed engagement while avoiding the diaphragm  30  having to be over-molded upon any other components, such as a cap or the like, and thereby avoiding the costs and complexities associated therewith. 
     The cap  52  may further include an outward facing flange  58 . The outward facing flange  58  is generally radially disposed and includes a circular edge. The diaphragm assembly  28  may further include a cap ring  60 . The cap ring  60  includes an inward facing circular slot  62 . The cap ring  60  may be attached to the cap  52  with the outward facing flange  58  disposed in the inward facing slot  62 . The cap ring  60  is concentrically disposed about the cap  52  with the cap  52  disposed between the cap ring  60  and the first retaining ledge  50  of the puller  32 . The cap ring  60  may be over-molded upon the cap  52  and may be formed of a material having a stiffness less than the stiffness of the cap  52 . In this regard, the cap ring  60  may be more flexible and softer than the cap  52 . The cap ring  60  may be disposed in contact with the back face  36  of the diaphragm  30 . 
     As the cap ring  60  may be configured to contact the back face  36  of the diaphragm  30 . Such contact may be used to push out the diaphragm  30  from the back face  36  in a direction of the front face  34  so as to spread the loading upon the diaphragm  30  and lessen wear at other locations about the diaphragm  30  (such as immediately adjacent the contact locations of the diaphragm end  42  of the puller  32  and the first retaining ledge  50 ). The contact by the cap ring  60  may also provide a degree of sealing with the diaphragm  30 . The cap ring  60  may also provide a degree of structural to support to the cap  52  to maintain the structural shape to the cap  52  as the cap  52  is exposed to compression forces with the diaphragm  30  being compressed in engagement with diaphragm end  42  of the puller  32 . 
     The puller  32  may further include a second retaining ledge  64  extending laterally from the puller body  46  and opposite the first retaining ledge  50  with respect to the puller longitudinal axis  48 . The puller  32  may be snap-fit through the diaphragm  30  with the second retaining ledge  64  also engaged with the cap  52 . In this regard, it is contemplated that there may be any number of addition retaining ledges similar to or different from the first and second retaining ledges  50 ,  64 . 
     The first retaining ledge may have a tapered surface  66  that is laterally more distant from the puller longitudinal axis in a direction from the cam end  44  toward the diaphragm end  42 . Such tapered surface  66  is contemplated to facilitate slidable contact between the first retaining ledge  50  and the diaphragm  50  at the top opening  38  upon insertion of the puller  32  and passage of the first retaining ledge  50  through the top opening  38 . However, rather than a smooth tapered surface  66 , a more stepped surface may be used. 
     It is contemplated that other configurations of the first and second retaining ledges  50 ,  64  may be implemented. In this regard, as used herein the terms first and second retaining ledges  50 ,  64  refer to a structure that laterally extends or protrudes from the puller body  46  capable of engagement or interference with a counter-force acting in a direction opposite to a movement of the puller  30  in a direction from the cam end  44  towards the diaphragm end  42  along the puller longitudinal axis  48 . Such configuration would also need to consider the degree of elastomeric deformation of the diaphragm  30  at the top opening  38  that may be required when inserting the puller  32  there through, and in particular the passage of the first and second retaining ledges  50 ,  64  there through. 
     The first and second retaining ledges and the puller body may be integrally formed of a single contiguous piece of material. In this regard, the first and second ledges  50 ,  64  may be used to engage the puller  32  with the diaphragm  30  in sealed engagement without the need for an additional separate attachment component, like a retaining bar, a spring pin or other fastener. This eases the task of assembly and reduces the overall number of components of the overall diaphragm assembly  28 . 
     It is contemplated that the materials and techniques used to manufacture of the various components of the diaphragm assembly  28  (such as the diaphragm  30 , the puller  32 , the cap  52  and the cap ring  60 ) may be chosen from those which are well known to one of ordinary skill in the art and may include, for example, injection molding and over-molding processes with various types of plastics and elastomeric materials as may be suitable for the particular intended applications. 
     The diaphragm end  42  of the puller  32  may include an end flange  72  with an overhang annular surface  74  facing the cam end  44 . The overhang annular surface  74  may be disposed in contact with the diaphragm  30  about the top opening  38  at the front face  34 . The overhang annular surface  74  may include concentric ridges  76 . In this regard the diaphragm  30  may include annular ribs  78  which extend from the front face  34  about the top opening  38 . The concentric ridges  76  may be cooperatively sized and configured with the annular ribs  78  and interspersed alternatively to form a sealing engagement between the diaphragm end  42  of the puller  32  and the diaphragm  30  at the top opening  38 . The annular ribs  78  may be relatively thin with a short profile so as to be crushable or readily deformable upon exposure to compressive forces. As such, a vacuum seal may be achieved with respect to the interior of the diaphragm  30  so as to prevent any gas passage between adjacent the front face  34  and the back face  36  of the diaphragm  30  through the top opening  38 . 
     The diaphragm assembly  28  may further include a cam  68  rotatably attached to the puller  32  adjacent the cam end  44 . It is understood that the puller  32 , as the name suggests, is used to repetitively pull the diaphragm  30 . Such reciprocating movement may be achieved through the rotation of the cam  68 . The cam  68  may be constructed and attached to the puller  32  in accordance to any of those techniques and materials which are well known to one of ordinary skill in the art. 
     With reference to the symbolic schematic diagram of  FIG. 14 , it is understood that diaphragm assembly  26  is suitable for use with a pump system  82 . In this regard, it is further understood that the diaphragm  30  may be used to form a portion of a vacuum chamber. In addition there is provided a drive mechanism  80  for powering reciprocating movement of the puller  32 . 
     According to another aspect of the present invention, there is provided a method of assembly of the diaphragm assembly  28 . The method includes providing the flexible diaphragm  30  having the front face  34  and the opposing back face  36 , and the top opening  38  formed through the diaphragm  30  and the bottom opening  40 . The method further includes providing the puller  30  having the diaphragm end  42 , the cam end  44 , the puller body  46  extending between the diaphragm end  42  and the cam end  44  along the puller longitudinal axis  48 , and the first retaining ledge  50  extending laterally from the puller body  46  with respect to the puller longitudinal axis  48 . The method further includes inserting the cam end  44  through the top opening  38  from the front face  34  until the first retaining ledge  50  is disposed at the back face  36 . 
     According to various embodiments, the method of assembly of the diaphragm assembly  28  may further include compressing the diaphragm  30  between the first retaining ledge  50  and the diaphragm end  42  of the puller  32 . The method of assembly of the diaphragm assembly  28  may further include providing the cap  52  having the cap central opening  54  concentrically disposed adjacent the top opening  38  at the back face  36  of the diaphragm  30 . The inserting of the cam end  44  may further include inserting the cam end  44  through the cap central opening  54  until the first retaining ledge  50  engages the cap  52 , with the cap  52  and the diaphragm  30  disposed between the diaphragm end  42  and the first retaining ledge  50  of the puller  32 . It is understood that the insertion of the cam end  44  refers to relative movement of the puller  32  to the diaphragm  30  and the cap  52 . As such, such insertion of the cam end  44  may include movement of the cap  52  about the cam end  44  and along the puller body  46  while the puller  52  is stationary. 
     The method of assembly of the diaphragm assembly  28  may further include attaching the cap ring  60  concentrically disposed about the cap  52 . The cap  52  is disposed between the cap ring  60  and the first retaining ledge  50  of the puller  32 . The cap ring  60  may be over-molded upon the cap  52 . In this regard, the cap  52  as combined with the cap ring  60  may be attached to the puller  32 . 
     The particulars shown herein are by way of example only for purposes of illustrative discussion, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the various embodiments set forth in the present disclosure. In this regard, no attempt is made to show any more detail than is necessary for a fundamental understanding of the different features of the various embodiments, the description taken with the drawings making apparent to those skilled in the art how these may be implemented in practice.