Abstract:
A retractable hose vacuum cleaning system comprising a retractable vacuum hose configured to retract through a dual port valve assembly, into a system vacuum tube responsive to the vacuum communicated from a vacuum source. The dual port valve assembly comprising one port adapted to receive the full length of a retractable vacuum hose into a system vacuum tube for storage, a second port adapted to connect to the hose end fitting and supply electrical grounding, electrical power and vacuum to the hose for use, valve seals to stop air flow through the port that is not in use and a third port to connect the valve to the system vacuum source. The dual port valve assembly also comprises a debris trap.

Description:
[0001]    This application claims the benefit of U.S. Provisional Application No. 61/519,842 filed May 31 2011. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates, generally, to vacuum cleaning systems. More particularly, the invention relates to central vacuum systems of the type having retractable suction hoses and valve assemblies that permit the hose to be moved into retractably stored position in the system vacuum tubing connecting the valve assembly to the central vacuum source. 
       BACKGROUND 
       [0003]    Central vacuum cleaning systems are well known and have been available for many years. One early design is 15 U.S. Pat. No. 3,593,363 issued in 1972 disclosing a central vacuum cleaning system using a retractable hose. The inserted end of the hose has a compressible annular seal. The hose is pulled out of the suction conduit located in a wall or floor until the foot end or inserted end reaches the receptacle mounted on the floor or wall, at which time the annular seal on the hose engages a corresponding annular abutment at the receptacle to hold the hose in position and seal between the hose and the receptacle. Accordingly, this design requires that the full length of the hose be pulled out prior to the user using the vacuum. 
         [0004]    In 1987, U.S. Pat. No. 4,688,596 issued disclosing a wall outlet box for a control vacuum system that connects to a vacuum hose. The &#39;596 design does not provide any hose storage, or retractable hose features. 
         [0005]    In 1990, U.S. Pat. No. 4,895,528 issued disclosing a hose-to-wall fitting for a central vacuum system. Like the earlier &#39;596 reference, the features of the &#39;528 patent were directed to a hose connection fitting only. 
         [0006]    Later, in 1996, U.S. Pat. No. 5,526,842 issued to Christensen disclosing a motorized hose wind-up mechanism that requires a somewhat complicated and expensive mechanism for the operation thereof. 
         [0007]    While most of the above noted central vacuum system designs include features that are useful in the task to perform the debris vacuum removal process, they typically do not provide a simple, quick way of deploying a long vacuum hose to a selected length. In addition, these designs do not address the problems associated with convenient storage of such long hoses. 
         [0008]    Accordingly, a need remains for a central vacuum cleaning system that is easy to install, and facilitates ease of deployment of the vacuum hose therein, and ease of storage of the same following the use of a long vacuum hose to quickly clean large areas. 
         [0009]    There is a recognized problem in the central vacuum cleaning industry with vacuum hose management. Typical vacuum hoses are 10 to 50 feet long; difficult to coil up, unwieldy to carry from room to room and bulky to store. Such central vacuum cleaning systems having retractable suction hoses and hose-retracting valve assemblies, that use vacuum suction to retract the hoses back into the system type vacuum plumbing, such as U.S. Pat. No. 7,010,829 B2 issued to Harman in 2006, provide a solution to this problem but heretofore have never been provided with the means to provide an electrical grounding path from the vacuum hose receptacle to the operator end of a hose equipped with a industry standard grounding conductor. 
         [0010]    Furthermore such central vacuum cleaning systems having retractable suction hoses and hose-retracting valve assemblies, that use vacuum suction to retract the hoses back into the system type vacuum plumbing, heretofore have never been provided with the means to provide electrical current along the hose to conventional tools attached to the end of the hose through various types of handles, extensions and fittings. 
         [0011]    Furthermore such central vacuum cleaning systems having retractable suction hoses and hose-retracting valve assemblies, that use vacuum suction to retract the hoses back into the system type vacuum plumbing, heretofore have never provided a sharp angle debris trap in the air stream adjacent to the vacuum valve to stop such items as pens, pencils and screw drivers from entering the system. 
         [0012]    Furthermore such central vacuum cleaning systems having retractable suction hoses and hose-retracting valve assemblies, that use vacuum suction to retract the hoses back into the system, and whose vacuum plumbing relies on traveling hose end seals or circumferential hose clamps and seals to prevent vacuum leakage and in the latter case to restrain hose movement while using the system. While both of these approaches provide use of the hose at any length extended they leak vacuum suction and their components are subject to wear and fatigue resulting in increased vacuum leakage and eventual failure. 
         [0013]    Briefly stated, this improved vacuum system has been achieved by using a dual port vacuum valve which allows the hose to be removed from the system tubing through a hose retraction port on the vacuum valve and the hose end fitting inserted into a vacuum inlet port on the vacuum valve which provides vacuum and electrical connections. The sharp, tight angle between the vacuum valve inlet and connection ports forms a debris trap. The moving hose end seal and circumferential hose clamp and seal described in U.S. Pat. No. 7,010,829 have been eliminated reducing the number of moving components thus improving reliability of the system and minimizing vacuum leakage. 
       SUMMARY OF THE INVENTION 
       [0014]    One object of the present invention is to provide a dual port valve assembly for a retractable vacuum hose cleaning system. The dual port valve assembly has two ports that interact with a retractable vacuum hose: a vacuum hose retraction port and vacuum hose inlet port. A third port, the vacuum connection port, connects the valve to vacuum system tubing and the vacuum source of the cleaning system. The vacuum retraction port is configured to allow the retractable hose to be stored in the system tubing, and the vacuum connection port is configured to receive the hose to form a tight seal to allow for use of the hose in vacuum cleaning. 
         [0015]    Another object of this invention is to provide a dual port valve assembly that has a conductor in its hose inlet port to provide a path for electrical ground to a retractable vacuum hose. The retractable vacuum hose can either have an attached electrical grounding conductor, such as a wire, or the hose can be made of an electrical grounding material, such as carbon impregnated plastic. Connection of the hose to the conductor in the hose inlet port provides electrical grounding for the hose. 
         [0016]    A further object of the instant invention is to provide a dual port valve assembly that has a conductor in its hose inlet port for electrical current from a power source. The conductor is configured to connect with a conductor in a retractable vacuum hose, so that electrical current may be provided through the conductor in the hose to the hose end cuff. Electrical current delivered through the vacuum hose may then be used to power a cleaning tool that attaches to the hose end cuff, and/or to provide control voltage for the system vacuum source. For example, the hose inlet port may contain 2 separate conductors, a higher voltage and lower voltage conductor. Each of these conductors connects to respective higher and lower voltage conductors in the vacuum hose, to provide power via the higher voltage conductor to a cleaning tool that attaches to the hose and to provide power via the lower voltage conductor for controlling operation of the central vacuum source. 
         [0017]    The present invention further provides for a dual port valve assembly for a vacuum cleaning system in which the valve assembly has a debris trap. The debris trap is formed by an angle between the axis of the vacuum hose inlet port and the axis of the vacuum connection port. 
         [0018]    Another object of this invention is to provide an improved vacuum cleaning system whereby an electrical current path is provided from the receptacle and along the hose to the operator end of the hose so as to provide a grounding path for static electricity. Typically, such hose is pre-wound with an electrical conductor fitted within its flexible coils. 
         [0019]    A further object of this invention is to provide an improved vacuum cleaning system whereby electrical current is supplied to the hose from the receptacle and along the hose so as to provide current to cleaning tools at the operator end of the hose. Typically, such hose is pre-wound with electrical wires fitted within its flexible coils. 
         [0020]    Yet another object of this invention is to provide an improved vacuum cleaning system whereby there is a tight angle debris trap in the air stream in or adjacent to the vacuum valve to capture such objects as pens, pencils and screwdrivers and prevent them from entering the vacuum system plumbing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which: 
           [0022]      FIG. 1  is a schematic perspective view of one embodiment of the improved vacuum cleaning system wherein the central vacuum source is connected via system vacuum tubing to one or more valve assemblies known in the industry as a “valve” that provide for a vacuum hose to be removed from the system vacuum tubing and vacuum valve assembly through one port and the hose end fitting inserted into a second port that provides vacuum and an electrical grounding path. 
           [0023]      FIG. 2  is an enlarged perspective view of the valve assembly mounted on a column or other structure showing the open or unsealed valve housing configuration, the dual port valve assembly, the vacuum hose with grounding conductor in the stored position with the hose cuff ball seal in place. The vacuum inlet port seal is closed. 
           [0024]      FIG. 3  is an enlarged perspective view of the vacuum valve assembly mounted on a column or other structure showing an open valve housing configuration, the dual port vacuum valve assembly and the vacuum hose with grounding conductor, end fitting ready for insertion into the vacuum inlet port. Hose retraction port seal is closed. 
           [0025]      FIG. 4  is an enlarged fragmentary horizontal sectional view taken along line A-A in  FIG. 3  showing the open housing configuration and valve assembly mounted on a vertical column or other structure and the vacuum hose with grounding conductor in the stored position. 
           [0026]      FIG. 5  is a schematic perspective view of one embodiment of the improved vacuum cleaning system wherein the central vacuum source is connected via system vacuum tubing to one or more valve assemblies known in the industry as a “valve” that provide for a vacuum hose to be removed from the system vacuum tubing and vacuum valve assembly through one port and the hose end fitting inserted into a second port that provides vacuum and electrical current. 
           [0027]      FIG. 6  is an enlarged perspective view of the valve assembly mounted in a vertical wall structure of a building showing the enclosed valve housing configuration, the dual port valve assembly, the vacuum hose with electrical conductors in the stored position. The double faced port seal is positioned to close the electrified vacuum inlet port. 
           [0028]      FIG. 7  is an enlarged perspective view of the valve assembly mounted in a vertical wall structure of a building showing the enclosed valve housing configuration, the dual port valve assembly, and the vacuum hose with electrical conductors. The hose is fitted on one end with a hose cuff making electrical contact with the hose conductors and on the other end with a hose end fitting making electrical contact with the hose conductors. The hose end fitting is equipped with electrical and vacuum connectors ready for insertion into the electrified vacuum inlet port. 
           [0029]      FIG. 8  is an enlarged fragmentary vertical sectional view taken along line B-B in  FIG. 6  and showing the sealed housing configuration with door closed and the valve assembly mounted in a vertical wall structure of the building. The vacuum hose is the stored position. 
           [0030]      FIG. 9  is an enlarged perspective view of the hose end fitting showing the high voltage electrical connectors and conductors and vacuum connections. 
           [0031]      FIG. 10  is an enlarged perspective view of the hose end fitting showing the low voltage electrical connectors and conductors and vacuum connections. 
           [0032]      FIG. 11  is an enlarged perspective view of the dual port vacuum valve with 2 single faced seals in the “hose stored” position. 
           [0033]      FIG. 12  is an enlarged perspective view of the dual port vacuum valve with 2 single faced seals in the “hose in use” position. 
           [0034]      FIG. 13  is an enlarged perspective view of the dual port vacuum valve with a single double faced seal in the “hose stored” position. 
           [0035]      FIG. 14  is an enlarged perspective view of the dual port vacuum valve with a single double faced seal in the “hose in use” position. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0036]    Referring more specifically to the drawings,  FIG. 1  is one embodiment of the improved vacuum cleaning system  8  of this invention which comprises a vacuum cleaning system of the type having a retractable suction hose  20 , a dual port valve assembly  10  and a central vacuum source  12 . A plurality of valve assemblies such as valve assembly  10  may be installed in the vacuum cleaning system and may be positioned at various locations in the building. 
         [0037]    The system utilizes industry standard vacuum plumbing with minor exceptions. Enlarged radius elbows  50  are required to allow the hose to pass through the bends in the system vacuum tubing for hose storage. A valve housing  26  is required to support the dual port vacuum valve and port seals and for sealing and restraining the tool end of the vacuum hose when in the stored position. Valve assembly  10  is communicatively connected by suitable system vacuum tubing  14  fitted with large radius elbows such as elbow  50  to facilitate hose storage and connected to the inlet of vacuum source  12 . 
         [0038]    Valve assembly  10  is preferably formed with a suitable open or unsealed valve housing  26  that may be installed on a column  18 , wall or other structure as is shown in  FIGS. 1 ,  2 ,  3  and  4 . Valve assembly  10  is configured so it can be removed from its mounted position for servicing and replacement without altering the building structure or the vacuum system plumbing. 
         [0039]      FIGS. 2 and 3  are enlarged views of vacuum valve assembly  10 . For system operation the vacuum hose  20  shown in  FIG. 3  is extracted from storage by pulling down and pushing back on spring loaded ball seal yoke  40  shown in  FIG. 2 , which is moveably attached to housing  26  by ball seal yoke guide pin  32  in a travel slot  44  in each side of housing  26 , to remove the ball seal  36  from the end of the hose end cuff  42 . Ball seal  36  is mounted on yoke  40  by way of ball seal shaft  46 . By releasing the ball yoke seal, it will move upwards behind hose end cuff  42  and out of the way. The hose end cuff  42  is grasped and pull downward and the full length of the hose is extracted. The operator then grasps finger tab  129  on hose retraction port seal  38 , better shown in  FIG. 4 , pulling it away from magnetic latch  56  and moves the seal to the closed position. Port seal  38  is typically spring loaded in the closed position but can be held in either its open or closed positions by springs, latches or other mechanisms. 
         [0040]    The operator then grasps finger tab  127  shown in  FIG. 2  on vacuum inlet port seal  28  with one hand and holds it open while inserting the hose end fitting  34  into vacuum inlet port  24  as shown in  FIG. 3 . Vacuum inlet port seal  28  is then allowed to rest on hose end fitting  34 . Hose retention hook  118  on vacuum inlet port seal  28  is permitted to engage hose retention groove  119  on hose end fitting  34  preventing the hose from being accidentally pulled from vacuum inlet port  24 . Vacuum inlet port seal  28  is normally spring loaded closed but can be held in its open and closed positions by springs, latches or other mechanisms. 
         [0041]    As best shown in  FIGS. 2 ,  3 , and  4 , vacuum inlet port  24  is oriented at a 90 degree angle to the axis of vacuum connection port  58  to form a sharp angle debris trap  60 . It can be oriented at an angle greater than 90 degrees if desired. However this will result in a more shallow angle in the debris trap decreasing its effectiveness in stopping foreign objects. 
         [0042]    The vacuum tool  52  can be attached to the vacuum hose end cuff  42  as shown in  FIG. 1  and the vacuum unit  12  can be turned on. The vacuum cleaning system is now ready to use in the conventional manner as shown in  FIG. 1 . 
         [0043]    Hose end fitting  34  and vacuum inlet port  24  shown in  FIG. 3  must be made from electrically conductive materials or contain electrical conductors that connect and provide a suitable path to ground. Hose end fitting  34  or its conductor are electrically connected to the conductor in vacuum hose  20  using industry standard techniques. 
         [0044]    When the operator is finished with the vacuuming task, cleaning tool  52  is removed from hose end cuff  42 . Cleaning tool  52  must be made from an electrically conductive material or contain suitable conductors that connect to hose cuff  42 . Vacuum hose  20  is retracted and stored by first grasping finger tab  129  on hose retraction port seal  38  shown in  FIG. 3  and moving it to and securing it in the open position with magnetic latch  56 . The latched position is shown in  FIG. 4 . This bleeds suction away from the vacuum inlet port  24 . 
         [0045]    The operator then grasps finger tab  127  shown in  FIG. 3  on vacuum inlet port seal  28  and lifts up slightly with one hand, releasing hose retention hook  118  from hose retention groove  119  and pulls the hose end fitting  34  from vacuum inlet port  24  with the other hand. The vacuum inlet port seal  28  is then moved to the closed position. 
         [0046]    Hose end fitting  34  can be inserted into hose retraction port  22 , which is now open as shown in  FIG. 4 , on the vacuum valve  16  and the system suction draws the hose  20  through the vacuum valve and into the system plumbing  14  until the hose end cuff  42  contacts retraction port lip  30  on retraction port  22  and stops as shown in  FIGS. 2 and 4 . The rate of hose retraction can be varied by restricting the air flow into hose end cuff  42  with the operator&#39;s hand or other air restriction device. 
         [0047]    The operator then grasps ball seal yoke  40  pulling downward and forward seating ball seal  36  over the open end of hose end cuff  42 . The spring loaded ball  36  forms a seal on one of hose cuff  42  and forces the opposite end of hose cuff  42  against retraction port lip  30  forming a seal. Hose retraction and storage are now complete as shown in  FIG. 4  and the operator may turn off vacuum unit  12  or leave it on depending on overall configuration and usage of the vacuum system. 
         [0048]    This system may be configured with a vacuum valve assembly that does not provide a path to electrical ground and a vacuum hose that does not contain an electrical grounding conductor. 
         [0049]    This system may be configured with a vacuum valve assembly that supplies electrical current to the vacuum inlet port, a vacuum hose containing electrical conductors and hose end fittings with electrical connectors to provide electrical current to a vacuum cleaning tool and provide control voltage for the vacuum unit  12  in a manner similar to that shown in  FIGS. 5 ,  6 ,  7  and  8 . 
         [0050]    Another embodiment of the improved vacuum cleaning system in this invention is shown in  FIGS. 5 ,  6 ,  7  and  8  and comprises a vacuum cleaning system  62  of the type having a retractable suction hose  64 , a dual port valve assembly  80  in a sealed housing and a central vacuum source  12 . A plurality of valve assemblies such as valve assembly  80  may be installed in the vacuum cleaning system  62  and may be positioned at various locations in the building. 
         [0051]    The system utilizes industry standard vacuum plumbing with minor exceptions. Enlarged radius elbows  50  are required to allow the hose to pass through the bends in the system vacuum tubing for hose storage and an enlarged valve housing is required to contain the hose clamping/sealing mechanism and for accessing the tool end of the vacuum hose. Valve assembly  80  is communicatively connected by suitable system vacuum tubing  14  fitted with large radius elbows  50  to facilitate hose storage and connected to the inlet of vacuum unit  12 . 
         [0052]    Valve assembly  80  is preferably formed with a sealed valve housing  102  that may be installed within a standard wall construction between wall surfaces  82  and  82 A as shown in  FIGS. 5 ,  6 ,  7  and  8 . Valve assembly  80  may be mounted to wall stud  86  or to wall  82  or  82 A and is designed to fit completely into the space inside a standard 2×4 stud wall  82  and  82 A through an opening in the wall that is larger, by a clearance gap, than the foot print of the valve housing face flange  116  shown in  FIG. 6 . Faceplate  109 , best shown in  FIG. 8 , and faceplate seal  112  mount to valve housing face flange  116 . Faceplate flange  110  fits flush with outside surface of wall  82 A and covers the clearance gap. Door  113  is hinged at door hinge  115  to faceplate  109 . Door seal  114  seals housing  102  air tight. 
         [0053]    As shown in  FIGS. 6 , and  7 , vacuum connection port  106  is connected to system vacuum tubing  14  with a suitable vacuum tubing coupling  120  and seal  104  to sealed housing  102 . 
         [0054]    When vacuum hose  64  is in the stored position as shown in  FIGS. 7 and 8  double faced port seal assembly  100  is covering and sealing inlet port  96 . The end of hose cuff  76  is open but there is no vacuum leakage because door  113  is closed making housing  102  air-tight. 
         [0055]    For system operation door  113  is opened and vacuum hose  64  is extracted from the system plumbing  14  through hose retraction port  78  by reaching inside valve housing  102 , grasping hose end cuff  76  and pulling down and outward. The full length of the hose must be extracted. 
         [0056]    The operator then grasps finger tab  121  on double faced port seal  100  as shown in  FIG. 6 , which now covers vacuum inlet port  96  with seal face  117 A, and pivots the seal over center around seal pivot post  108  until the seal now covers and seals retraction port  78  with seal face  117  leaving vacuum inlet port  96  open. 
         [0057]    Double faced port seal  100  typically has a material suitable for sealing attached to both sides forming seal faces  117  and  117 A. Double faced port seal  100  has dimensions and geometry which allow it to cover and seal vacuum inlet port  96  in one operating position and hose retraction port  78  in the other operation position when rotated around seal pivot post  108 . It is held in either of its two operating positions by over center spring(s)  98 . However it can be held in either position by latches, springs or other mechanisms. 
         [0058]    Best shown in  FIG. 7 , the operator then inserts hose end fitting  84  into vacuum inlet port  96  and thereby mates electrical connector  92  on hose fitting  84  with electrical connector  90  in vacuum inlet port  96 . Similarly, mating of low voltage electrical connector (not shown) on hose fitting  84  with low voltage electrical connector  91  in vacuum inlet port  96  occurs. High and low voltage is brought to port  96  by way of high and low voltage electrical conductors  88 . Hose end fitting  84  orientation is keyed so house and low voltage contacts cannot be crossed. While not shown, a detent or twist lock feature can be employed to prevent accidental extraction of hose end fitting  84  from hose port  96 . 
         [0059]    Vacuum inlet port  96  is shown in  FIG. 7  oriented at a 90 degree angle to the axis of vacuum connection port  106 . It can be oriented at an angle greater than 90 degrees if desired. However this will result in a shallower angle in the debris trap decreasing its effectiveness in stopping foreign objects. 
         [0060]    The operator now attaches hose handle  68  as shown in  FIG. 5  to the vacuum hose end cuff  76  which is equipped with electrical connectors to provide electrical current to hose handle  68 . Hose handle  68  and wand  70  are equipped with electrical connectors, conductors and switches to provide and control electrical current to vacuum cleaning tool  74 . Hose handle  68  is equipped with connectors, conductors and switches to provide control voltage for the vacuum unit  12 . Vacuum cleaning system  62  is now ready to use in the conventional manner as shown in  FIG. 5 . 
         [0061]    When the operator is finished with the cleaning task hose handle  68  is removed from hose end cuff  76 . Vacuum hose  64  as shown in  FIG. 7  is retracted and stored by grasping hose end fitting  84  with one hand, releasing the latching mechanism if used, and pulling it out of vacuum inlet port  96 . The operator then pivots double faced port seal  100  around pivot post  108  until the seal face  117  now covers and seals vacuum inlet port  96  leaving hose retraction port  78  open. 
         [0062]    The operator then inserts hose end fitting  84  into hose retraction port  78  on the dual port vacuum valve  94  and the system suction draws the hose through the vacuum valve and into the system plumbing  14  until the hose end cuff  76  contacts hose retraction and storage port lip  81  on retraction port  78  and stops as shown in  FIG. 7 . The rate of hose retraction can be varied by restricting the air flow into hose end cuff  76  with the operator&#39;s hand or other air restriction device. 
         [0063]    Hose retraction and storage are now complete as shown in  FIGS. 7 and 8 . The operator then closes door  113  to seal the valve housing and may turn off vacuum unit  12 . 
         [0064]    Hose end fitting  84  as shown in  FIG. 9  provides high voltage connectors  92  which are electrically attached to conductors  121 A which attach to electrical conductors in vacuum hose  64  in  FIG. 7 . These are used to provide electrical power to an electrical tool at the other end of the hose  64  or handle  68  as shown in  FIG. 5 . 
         [0065]    Hose end fitting  84  as shown in  FIG. 10  provides low voltage connectors  123  which are electrically attached to conductors  124  which attach to electrical conductors in vacuum hose  64  in  FIG. 7 . These provide control voltage to a switch at the opposite end of the hose, handle or tool as shown in  FIG. 5  and are used for turning the vacuum source  12  on and off. 
         [0066]    Hose end fitting  84  as shown in  FIG. 10  also provides a vacuum port connector  125  for connection to vacuum inlet port  96  in  FIG. 7 . Hose end fitting  84  provides a hose connector  122  as shown in  FIG. 9  for connecting to hose  64  in  FIG. 7  providing a vacuum passage  126  from vacuum inlet port  96  to hose  64 . 
         [0067]    As shown in  FIG. 11 , the dual port vacuum valve  16  is depicted with single faced port seal  28  and single faced port seal  38  in the “hose stored” position. 
         [0068]    As shown in  FIG. 12 , the dual port vacuum valve  16  is depicted with single faced port seal  28  and single faced port seal  38  in the “hose in use” position. 
         [0069]    Dual port vacuum valve  94  is best depicted in  FIGS. 13 and 14 . 
         [0070]    This system may be configured as a “non-electrified” version with a vacuum valve assembly that supplies vacuum to the inlet port, an electrical path from the vacuum inlet port to ground for static electricity and a vacuum hose that contains an electrical conductor for grounding purposes similar to that shown in  FIGS. 1 ,  2 ,  3 , and  4 . 
         [0071]    This system may be configured with a vacuum valve assembly that does not provide a path to electrical ground and a vacuum hose that does not contain an electrical grounding conductor. 
         [0072]    In the drawings and specifications there have been set forth preferred embodiments of the invention and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation. The design of the hose seal and restraint depicted in this invention combine several functions, that of sealing, restraining and wear reduction, into one device or mechanism. Separate devices or mechanisms could be used for each function. Other devices or mechanisms could be used to achieve the functions and results. 
         [0073]    In addition, whereas the drawings and specifications relate to central vacuum cleaning systems for a home or building, the application is not limited to this industry alone but to any industry or operation where a vacuum system is used. 
         [0074]    Having illustrated and described the principles of my invention in a preferred embodiment thereof, it should be readily apparent to those skilled in the art that the invention can be modified in arrangement and detail without departing from such principles. I claim all modifications coming within the spirit and scope of the accompanying claims.