Patent Publication Number: US-7723625-B1

Title: Ultra low pressure switch system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   Not applicable to this application. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable to this application. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to pressure switches and more specifically it relates to an ultra low pressure switch system for efficiently reducing switch deterioration. 
   2. Description of the Related Art 
   Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. 
   Pressure switches have been in use for years. Typically, low pressure switches utilize a deflecting beam contact and a stationary contact, wherein a desired pressure will move the deflecting beam contact downward against the stationary contact thus completing a circuit. The prior pressure switches are generally constructed using rivets through a plastic housing of the pressure switch. The rivets generally pass through the housing and connect the stationary contact and deflecting beam contact to the outside of the pressure switch. 
   Small variations of pressure switch walls typically found in plastic components can make it difficult to control riveting operations through the contacts. This can make it very difficult to control the placement of the stationary contact and deflecting beam contact upon the rivet. The result of the contacts not maintaining a consistent distance from one another may result in a different trip point for every low pressure switch. The switches also often have to be calibrated after they are riveted which can be very costly and time consuming. 
   Environments in which the pressure switches are utilized in generally are very inconsistent. Expansion and contraction of the chamber walls of the switch from temperature changes and induced stress during riveting operation of the contacts may have a significant effect over the functioning and stability of the switch trip points. Because of the general lack of efficiency and practicality in the prior art there is the need for a new and improved ultra low pressure switch system for efficiently reducing switch deterioration. 
   BRIEF SUMMARY OF THE INVENTION 
   The general purpose of the present invention is to provide an ultra low pressure switch system that has many of the advantages of the pressure switches mentioned heretofore. The invention generally relates to a pressure switch which includes a housing comprised of a first portion and a second portion, wherein the first portion and the second portion define a cavity between thereof, a first port fluidly connected to the housing, a diaphragm member positioned within the cavity, a first terminal positioned within the cavity, a second terminal positioned within the cavity and a spacer member positioned within the cavity and between the first terminal and the second terminal. 
   There has thus been outlined, rather broadly, some of the features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and that will form the subject matter of the claims appended hereto. 
   In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction or to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting. 
   An object is to provide an ultra low pressure switch system for efficiently reducing switch deterioration. 
   Another object is to provide an ultra low pressure switch system that is small in size. 
   An additional object is to provide an ultra low pressure switch system that is not affected by temperature changes. 
   A further object is to provide an ultra low pressure switch system that requires no calibration after the switch has been manufactured. 
   Another object is to provide an ultra low pressure switch system that is low in cost. 
   Other objects and advantages of the present invention will become obvious to the reader and it is intended that these objects and advantages are within the scope of the present invention. To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
       FIG. 1  is a side cutaway view of a prior art pressure switch. 
       FIG. 2  is an upper perspective view of the present invention. 
       FIG. 3  is an exploded upper perspective view of the present invention. 
       FIG. 4  is a top view of the present invention. 
       FIG. 5  is a bottom view of the present invention. 
       FIG. 6  is a cross-sectional view taken along line  6 - 6  of  FIG. 4 . 
       FIG. 7  is a cross sectional view with the upper casing removed from the lower casing. 
       FIG. 8  is a cross sectional view with the upper casing partially attached to the lower casing. 
       FIG. 9  is a cross sectional view with the upper casing attached to the lower casing. 
       FIG. 10  is an exploded upper perspective view of the first terminal and the first portion. 
       FIG. 11  is an exploded upper perspective view of the first terminal attached to the first portion. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   A. Overview 
   Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views,  FIGS. 2 through 11  illustrate an ultra low pressure switch system  10 , which comprises a housing  20 ,  60  comprised of a first portion  20  and a second portion  60 , wherein the first portion  20  and the second portion  60  define a cavity  23  between thereof, a first port  21  fluidly connected to the housing  20 ,  60 , a diaphragm member  40  positioned within the cavity  23 , a first terminal  30  positioned within the cavity  23 , a second terminal  50  positioned within the cavity  23  and a spacer member  40  positioned within the cavity  23  and between the first terminal  30  and the second terminal  50 . 
   B. First Housing Portion 
   The first housing portion  20  is preferably comprised of a substantially circular configuration as illustrated in  FIGS. 2 and 3 ; however it is appreciated that the first housing portion  20  may be comprised of various configurations rather than the preferred embodiment, such as but not limited to elliptical or rectangular. The first housing portion  20  is preferably comprised of a material to withstand variant temperatures and pressures. The first housing portion  20  is also preferably able to expand and contract accordingly with variant environment conditions. The material of the first housing portion  20  is further preferably comprised of plastic; however other suitable materials may be utilized with the first housing portion  20  rather than the preferred material. 
   The first housing portion  20  includes a first port  21 , wherein the first port  21  preferably receives a first pressure. The first port  21  is preferably comprised of a tubular configuration. The first port  21  also preferably extends horizontally outward from the first housing portion  20  as illustrated in  FIGS. 2 through 5 . The first port  21  is also preferably fluidly connected to an inner portion of the first port  21 . The first pressure of the first port  21  is preferably comprised of a vacuum pressure. 
   The first housing portion  20  also includes at least one mounting member  28  as shown in  FIGS. 2 through 5 . The mounting member  28  preferably extends horizontally outward from the first housing portion  20 . There preferably exists a mounting member  28  on each opposing side of the first housing portion  20 . The mounting members  28  also preferably each receive a screw or other fastener to fasten the ultra low pressure switch system  10  to an object. 
   The first housing portion  20  also preferably includes a plurality of slots  22 . The plurality of slots  22  preferably vertically extends through the first housing portion  20 . The plurality of slots  22  are also preferably radially positioned substantially near an outer edge of the first housing portion  20  as shown in  FIG. 5 . 
   An outer wall of the first housing portion  20  preferably includes a first recessed portion  24  and a second recessed portion  26 . The first recessed portion  24  and the second recessed portion  26  preferably both form a depression along the outer wall of the first housing portion  20  as illustrated in  FIGS. 3 ,  10  and  11 . The first recessed portion  24  is preferably at a substantially lower vertical height than the second recessed portion  26 . The first recessed portion  24  and the second recessed portion  26  are also both preferably comprised of a rectangular configuration; however it is appreciated that the first recessed portion  24  and the second recessed portion  26  may be comprised of various configurations rather than the preferred embodiment. 
   Extending vertically upward from the first recessed portion  24  is preferably a first connecting member  25 . A second connecting member  27  also preferably extends vertically upward from the second recessed portion  26 . The first connecting member  25  and the second connecting member  27  are both preferably comprised of a pin configuration. A first width of the first connecting member  25  and a second width of the second connecting member  27  are each preferably substantially less than a width of the outer wall of the first housing portion  20  as shown in  FIGS. 3 ,  10  and  11 . 
   The first housing portion  20  also includes a cavity  23 . The cavity  23  of the first housing portion  20  is preferably comprised of a circular configuration. The cavity  23  of the first housing portion  20  preferably extends within the first housing portion  20  to receive the first terminal  30 , the plurality of seal members  42 , the spacer member  40 , the diaphragm member  44  and the second terminal  50 . An outer diameter of the cavity  23  is preferably substantially similar to an outer diameter of the first outer member  32  of the first terminal  30  and to an outer diameter of a second outer member  52  of the second terminal  50 . 
   An adjustment member  29  is also preferably removably attached to a lower end of the first housing portion  20 . The adjustment member  29  is preferably threadably attached to the first housing portion  20 . The adjustment member  29  is preferably threadably positioned against the first terminal  30  to adjust the pressure that is desired to complete the circuit of the ultra low pressure switch system  10 . 
   C. First Terminal 
   The first terminal  30  is preferably comprised of a substantially circular configuration; however it is appreciated that the first terminal  30  may be comprised of various configurations rather than the preferred embodiment, such as but not limited to elliptical or rectangular. The first terminal  30  is also preferably positionable within the cavity of the first housing portion  20  as illustrated in  FIGS. 3 ,  10  and  11 . The first terminal  30  is preferably comprised of a metal material. The first terminal  30  is further preferably comprised of an electrically conductive material. 
   The first terminal  30  preferably includes a first outer member  32  and a first inner member  36 . The first outer member  32  is preferably comprised of a ring configuration as shown in  FIGS. 3 ,  10  and  11 . The first outer member  32  is further preferably comprised of a hard metal material so as not to bend or deform over extended use. An outer diameter of the first outer member  32  is preferably substantially similar to an outer diameter of the cavity  23 . 
   The first outer member  32  preferably includes a first extended portion  34  and a first fulcrum portion  33 . The first extended portion  34  preferably extends outwardly to form the first outer member  32 . The first extended portion  34  is further preferably comprised of a rectangular configuration. The first extended portion  34  is preferably positionable within the first recessed portion  24  of the first housing portion  20 . 
   The first outer member  32  also preferably includes a first connecting aperture  39 . The first connecting aperture  39  extends through the first extended portion  34 . The first connecting aperture  39  further preferably aligns with the first connecting member  25  and is positionable over the first connecting member  25  thus securing the first terminal  30  within the first housing portion  20  as illustrated in  FIGS. 10 and 11 . 
   The first outer member  32  also preferably includes a first fulcrum portion  33 . The first fulcrum portion  33  preferably extends across the first outer member  32 . The first fulcrum portion  33  preferably provides an overlapping region for the first inner member  36  to attach to the first outer member  32 . 
   The first inner member  36  is preferably comprised of a circular configuration. An outer diameter of the first inner member  36  is also preferably slightly less than an inner diameter of the first outer member  32 . The first inner member  36  is also preferably comprised of a brass material; however other materials may be utilized with the first inner member  36  rather than the preferred material. 
   The first inner member  36  is preferably spot welded to the first fulcrum portion  33  of the first outer member  32 . Utilizing weld substance as a fastener between the first inner member  36  and the first outer member  32  preferably prevents the first inner member  36  from becoming loose upon the first outer member  32  over extended use. A concentric origin of the first inner member  36  is also preferably substantially similar to a concentric origin of the first outer member  32  when attaching the first inner member  36  to the first outer member  32 . 
   The first inner member  36  also preferably includes a first contact  37 . The first contact  37  preferably extends upward from an outer edge of the first inner member  36 . The first inner member  36  is also preferably attached to the first outer member  32  in a manner, wherein an electrical current is able to flow between the first contact  37  and the first extended portion  34  of the first outer member  32 . 
   D. Second Terminal 
   The second terminal  50  is preferably comprised of a substantially circular configuration; however it is appreciated that the first terminal  30  may be comprised of various configurations rather than the preferred embodiment, such as but not limited to elliptical or rectangular. The second terminal  50  is also preferably positionable within the cavity of the second housing portion  60  as illustrated in  FIG. 3 . The second terminal  50  is preferably comprised of a metal material. The second terminal  50  is further preferably comprised of an electrically conductive material. Further, the second terminal  50  and the first terminal  30  are preferably comprised of substantially similar configurations. 
   The second terminal  50  preferably includes a second outer member  52  and a second inner member  56 . The second outer member  52  is preferably comprised of a ring configuration as shown in  FIG. 3 . The second outer member  52  is further preferably comprised of a hard metal material so as not to bend or deform during or after extended use. An outer diameter of the second outer member  52  is preferably substantially similar to an outer diameter of the cavity  23 . 
   The second outer member  52  preferably includes a second extended portion  54  and a second fulcrum portion  53 . The second extended portion  54  preferably extends outwardly form the second outer member  52 . The second extended portion  54  is further preferably comprised of a rectangular configuration. The second extended portion  54  is preferably positionable within the second recessed portion  26  of the second housing portion  60 . 
   The second outer member  52  also preferably includes a second connecting aperture  59 . The second connecting aperture  59  extends through the second extended portion  54 . The second connecting aperture  59  further preferably aligns with the second connecting member  27  and is positionable over the second connecting member  27  thus securing the second terminal  50  within the second housing portion  60 . The second outer member  52  also preferably includes a second fulcrum portion  53 . The second fulcrum portion  53  preferably extends across the second outer member  52 . The second fulcrum portion  53  preferably provides an overlapping region for the second inner member  56  to attach to the second outer member  52 . 
   The second inner member  56  is preferably comprised of a circular configuration. An outer diameter of the second inner member  56  is also preferably slightly less than an inner diameter of the second outer member  52 . The second inner member  56  is also preferably comprised of a brass material; however other materials may be utilized with the second inner member  56  rather than the preferred material. 
   The second inner member  56  is preferably spot welded to the second fulcrum portion  53  of the second outer member  52 . Utilizing weld substance as a fastener between the first inner member  56  and the first outer member  52  preferably prevents the first inner member  56  from becoming loose upon the first outer member  52  over extended use. A concentric origin of the second inner member  56  is also preferably substantially similar to a concentric origin of the second outer member  52  when attaching the second inner member  56  to the second outer member  52 . 
   The second inner member  56  also preferably includes a second contact  57 . The second contact  57  preferably extends downward from an outer edge of the second inner member  56 . The second inner member  56  is also preferably attached to the second outer member  52  in a manner, wherein an electrical current is able to flow between the second contact  57  and the second extended portion  54  of the second outer member  52 . 
   The second inner member  56  also preferably includes a pivot slot  55  positioned on an inside edge of the second fulcrum portion  53  of the second outer member  52  as shown in  FIG. 3 . The pivot slot  55  preferably allows the second inner member  56  to pivot about the second outer member  52 . 
   The second contact  57  is preferably positioned so that when the second inner member  56  pivots the second contact  57  is able to be positioned against the first contact  37  of the first inner member  36 . When the first contact  37  and the second contact  57  are positioned against one another a circuit is preferably completed thus allowing an electrical current to flow from the first extended portion  34  of the first terminal  30  to the second extended portion  54  of the second terminal  50  or vice versa. 
   The ultra low pressure switch system  10  also preferably includes a plurality of seal members  42 , at least one spacer member  40  and at least one diaphragm member  44 . The seal members  42  are preferably comprised of an O-ring configuration. The seal members  42  are further preferably comprised of a rubber material so as to provide a fluid seal within the ultra low pressure switch system  10 . An outer diameter of the seal member  42  is preferably comprised of a substantially similar size and configuration as the outer diameter of the first outer member  32  and the second outer member  52 . 
   The seal members  42  are preferably spaced at various positions within the ultra low pressure switch system  10  where a fluid seal is desired. The seal members  42  preferably prevent the first pressure and/or the second pressure from escaping the cavity  23  of the housing  20 ,  60  through the outer wall. The seal members  42  are also preferably able to expand and contract with the housing  20 ,  60  to consistently provide a fluid seal within the ultra low pressure switch system  10  for multiple environmental conditions. The seal members  42  also preferably fit within a channel  62  of the first housing portion  20 , second housing portion  60  and upper and lower ends of the spacer member  40  as illustrated in  FIGS. 6 through 8 . The channels  62  are also preferably formed to receive the seal members  42  and prevent the seal members  42  from moving from side to side while positioned within the channels  62 . 
   The spacer member  40  is preferably positioned between the first outer member  32  and the second outer member  52  to prevent and keep a consistent distance between the first outer member  32  and the second outer member  52 . The spacer member  40  preferably moves up and down with the terminals  30 ,  50  and expansion/contraction of the housing  20 ,  60 . The spacer members  40  are preferably comprised of an O-ring configuration. The spacer member  40  is further preferably comprised of a thermoplastic or ceramic material; however it is appreciated that the spacer member  40  may be comprised of various materials rather than the preferred embodiment. 
   It is appreciated that the number of spacer members  40  utilized depends on the size and configuration of the ultra low pressure switch system  10 . An outer diameter and an inner diameter of the spacer member  40  are preferably comprised of a substantially similar size and configuration as the outer diameter and the inner diameter of the first outer member  32  and the second outer member  52 . It is further appreciated that the spacer member  40  may be weldably attached between the first terminal  30  and the second terminal  50 . 
   The diaphragm member  44  is preferably comprised of a circular configuration. The diaphragm member  44  is also preferably comprised of a material to prevent the passage of the fluid throughout the ultra low pressure switch system  10  from the first port  21  or the second port  61 . The diaphragm member  44  preferably forms a first cavity portion and a second cavity portion within the cavity  23  of the housing  20 ,  60 , wherein the first cavity portion is fluidly sealed from the second cavity portion. An outer diameter of the diaphragm member  44  is preferably comprised of a substantially similar size and configuration as the outer diameter of the second outer member  52 . The diaphragm member  44  is preferably attached to an upper end of the second outer member  52  and provides a barrier to prevent the second inner member  56  from pivoting upward. 
   E. Second Housing Portion 
   The second housing portion  60  is preferably comprised of a substantially circular configuration as illustrated in  FIGS. 2 through 4 ; however it is appreciated that the second housing portion  60  may be comprised of various configurations rather than the preferred embodiment, such as but not limited to elliptical or rectangular. The second housing portion  60  is preferably comprised of a material to withstand variant temperatures and pressures. The second housing portion  60  is also preferably able to expand and contract accordingly with variant environment conditions. The material of the second housing portion  60  is further preferably comprised of plastic; however other suitable materials may be utilized with the second housing portion  60  rather than the preferred material. 
   The second housing portion  60  includes a second port  61 , wherein the second port  61  preferably receives a second pressure. The second port  61  is preferably comprised of a tubular configuration. The second port  61  also preferably extends horizontally outward from the second housing portion  60  at an opposing side as the first port  21  as illustrated in  FIGS. 2 through 5 . The second port  61  is also preferably fluidly connected to an inner portion of the second port  61 . The second pressure of the second port  61  is preferably comprised of an outwardly blowing pressure. 
   The second housing portion  60  also preferably includes a plurality of attachment members  63 . The plurality of attachment members  63  preferably vertically extend from the second housing portion  60 . The plurality of attachment members  63  are also preferably radially positioned substantially near an outer edge of the second housing portion  60  as shown in  FIGS. 3 and 5 . The attachment members  63  are further preferably positioned to align with the slots  22  of the first housing portion  20 . 
   Each of the attachment members  63  preferably includes a locking portion  64 . The locking portion  64  preferably extends out horizontally from the attachment members  63  as shown in  FIGS. 7 through 9 . The locking portion  64  is also preferably positioned at a lower end of the attachment members  63 . The locking portion  64  preferably extends horizontally beyond a lower end of the slots  22  when the attachment members  63  are positioned within the slots  22 . The locking portion  64  further preferably prevent the attachment members  63  and second housing portion  60  from being easily removed from the first housing portion  20 . 
   An outer wall of the second housing portion  60  preferably includes a first connecting portion  66  and a second connecting portion  68 . The first connecting portion  66  and the second connecting portion  68  preferably both extend vertically downward from the outer wall of the second housing portion  60  as illustrated in  FIGS. 2 and 3 . The first connecting portion  66  is preferably positioned at a substantially lower vertical height than the second connecting portion  68 . 
   The first connecting portion  66  and the second connecting portion  68  are also both preferably comprised of a rectangular configuration; however it is appreciated that first connecting portion  66  and the second connecting portion  68  may be comprised of various embodiments rather than the preferred embodiment. The first connecting portion  66  is preferably substantially similar in size and configuration to the first recessed portion  24 . The second connecting portion  68  is also preferably substantially similar in size and configuration to the second recessed portion  26 . 
   Extending vertically upward from the first connecting portion  66  is preferably a first receiving aperture  67 . A second receiving aperture  69  also preferably extends vertically upward from the second connecting portion  68 . The first receiving aperture  67  preferably receives the first connecting member  25  and the second receiving aperture  69  preferably receives the second connecting member  27 . When the second housing portion  60  is attached to the first housing portion  20  the first extended portion  34  of the first terminal  30  is preferably sandwiched between the first connecting portion  68  and the first recessed portion  24 . The second terminal  50  is also preferably sandwiched between the second connecting portion  69  and the second recessed portion  25  when the second housing portion  60  is attached to the first housing portion  20 . 
   F. Assembly of Invention 
   In assembly, the first housing portion  20  is first positioned so that the cavity  23  faces upward. A first seal member  42  is then positioned within the channel  62  of the cavity  23 . The first terminal  30  is then positioned over the first seal member  42 , wherein the first connecting aperture  39  of the first terminal  30  is positioned over the first connecting member  25  of the first housing portion  20 . A second seal member  42 , subsequent spacer member  40  and subsequent third seal member  42  are then positioned over the first terminal  30 , wherein the second seal member  42  is positioned within a channel  62  adjacent to the lower end of the spacer member  40  and the third seal member  42  is positioned within the channel  62  adjacent to the upper end of the spacer member  40 . It is appreciated that more or less seal members  42  and spacer members  40  may be utilized if desired with the ultra low pressure switch system  10 . 
   The second terminal  50  is then preferably positioned over the third seal member  42 , wherein the second connecting aperture  59  of the second terminal  50  is positioned over the second connecting member  27  of the first housing portion  20 . The first terminal  30  is fluidly sealed with respect to the second terminal  50  and the first housing portion  20  via the spacer member  40 , second seal member  42  and third seal member  42 . The diaphragm member  44  is then attached to the upper end of the second terminal  50  and a fourth seal is then positioned over the diaphragm member  44  and within the channel  62  of the second housing portion  60 . 
   The diaphragm member  44  is preferably fluidly sealed with respect to the second housing portion  60  of the housing  20 ,  60  defining a first cavity portion within the housing  20 ,  60 . The second terminal  50  is preferably fluidly sealed with respect to the diaphragm member  44 . A second cavity portion is formed within the housing between the diaphragm member, the first terminal, the second terminal and the first portion of the housing. The second cavity portion is also preferably fluidly sealed from the first cavity portion. 
   The second housing portion  60  is then attached to the first housing portion  20  via the attachment slots  22  removably attaching within the slots  22  and the connecting portions  66 ,  68  removably attaching within the recessed portions  24 ,  26 . The first terminal  30 , plurality of seal members  42 , spacer member  40 , second terminal  50  and diaphragm member  56  are all preferably freely floating within the first housing portion  20  and the second housing portion  60  when the ultra low pressure switch system  10  is assembled. 
   The free floating structure allows the ultra low pressure switch system  10  to expand and contract while maintaining a consistent trip point for the first pressure or the second pressure. What has been described is the preferred method of assemblage as illustrated in  FIG. 3 . Other methods of assemblage may be utilized with the ultra low pressure switch system  10 . 
   G. In Use 
   In use, the adjustment member  29  is first adjusted so that the second contact  57  of the second terminal  50  makes contact with the first contact  37  of the first terminal  30  at the desired pressure. Extending the adjustment member  29  upwardly forces the first inner member  36  of the first terminal  30  upward thus reducing the pressure needed to complete the circuit of the first terminal  30  and the second terminal  50 . Lowering the adjustment member  29  subsequently lowers the first inner member  36  of the first terminal  30  thus increasing the pressure needed to complete the circuit of the first terminal  30  and the second terminal  50 . 
   A pressure hose may now be attached to the first port  21  or the second port  61 . If the pressure hose is comprised of a vacuum hose the pressure hose is preferably removably attached to the first port  21 . The first pressure of the first port  21  pulls the second inner member  56  downward to complete the circuit. If the pressure hose is comprised of a forwardly blowing pressure hose the pressure hose is preferably removably attached to the second port  61 . The second pressure of the second port  61  pushes the second inner member  56  downward to complete the circuit. 
   To remove the second housing portion  60  from the first housing portion  20  an inward force is applied to the attachment members  63  forcing the locking portion  64  of the adjustment members  63  to align with the slots  22  of the first housing portion  20 . The second housing portion  60  may now be pulled away from the first housing portion  20 . 
   What has been described and illustrated herein is a preferred embodiment of the invention along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations are possible within the spirit and scope of the invention, which is intended to be defined by the following claims (and their equivalents) in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Any headings utilized within the description are for convenience only and have no legal or limiting effect.