Abstract:
The invention relates to an improved stuffing tube assembly ( 100 ) and method for traversing a bulkhead with a cable. The stuffing tube assembly ( 100 ) can accommodate a plurality of cables of varying cross-sectional areas. The improved stuffing tube ( 100 ) can also allow cables to pass through the stuffing tube ( 100 ) without having to remove and/or resolder the cables&#39; end connectors. The invention can include a resilient material that is positioned between two opposing flanges ( 407, 413 ). A cable bore ( 112 ) can define an opening extending through the resilient material. A compression device can include a system of opposing flanges ( 407, 413 ). When the compression device selectively applies a compressive force to the resilient material, the distance between the opposing flanges ( 407, 413 ) can be varied. The compressive force can vary the cross-sectional profile of the cable bore (112) such that the cross-sectional profile of the cable bore ( 112 ) engages a peripheral portion of the cable where the cable passes through the cable bore ( 112 ).

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Statement of the Technical Field  
         [0002]     The inventive arrangements generally relate to a cable stuffing tube. In particular, the invention relates to an improved multi-cable stuffing tube assembly.  
         [0003]     2. Description of the Related Art  
         [0004]     Communication system devices often require the use of stuffing tubes where cables are extended through bulkheads. Conventional stuffing tubes typically contain an asbestos or other polymer composition seal that is wrapped around the cable to create an airtight seal around the cable. Various machined parts are used to compress the seal so as to substantially prevent air flow from one side of the bulkhead to the other. Air flow prevention is usually needed to meet equipment specifications.  
         [0005]     Considering that electrical cables come in many different diameters, a comparable number of sizes of tubular bodies has been necessary for conventional stuffing tubes. The current state of the art consists of Heyco® fittings, customized bulkhead panels with panel mount connectors, and even empty stuffing tubes packed with putty or rubber corking. In view of this large variety of sizes and types of tubular bodies and panel mount connectors, the inventory costs to maintain such variety of wire protection devices increases. In addition, this variety also makes such installations even more complex.  
         [0006]     A further problem arises in the context of military vehicle or shelter overhauling and refurbishing. This problem relates to changes in the size of electrical cables. For example, cables are sometimes reduced in size due to the different electrical requirements of modern electronic equipment. This has meant that the old tubular bodies, which have been previously welded into place, have had to be cut out of the bulkheads and replaced with new and different sized tubular bodies. Again, the cost has been very high and the time required has been excessive. Many prior stuffing tube installations also have a tendency to leak, requiring a great deal of time and expense in reworking to make them substantially airtight in accordance with equipment specifications.  
         [0007]     Aside from changing the size of electrical cables, cable routing assignments may require changing the number of cables that are employed. Changing the number of cables has sometimes meant that additional bulkhead holes must be created and additional stuffing tubes must be welded into place. Currently, most NATO and ex-Soviet armored vehicle antenna feed-thru hole patterns, which number in the millions, are potentially affected by cable rework upgrades.  
         [0008]     To compound the difficulties in rearranging cable routes, the cables that pass through the stuffing tubes must typically have their connectors removed before inserting or removing the cables from their respective stuffing tubes. Cable connectors often have a diameter that is considerably larger than the cable to which they are attached. The cable stuffing tube often will not accommodate the larger connector. Accordingly, the connectors must be removed before the cable is passed through a bulkhead. This rework task is also very time consuming. On average, the rework time per cable per vehicle takes about 1-2 hours. The problem is compounded when such reworking occurs in an uncontrolled environment such as in a combat zone, where the conditions may not offer the best probability for quality workmanship.  
         [0009]     Therefore, what is needed is a cable stuffing tube design that can accommodate greater adaptability in cable reworking. Such a design should accommodate cables of varying sizes and quantities. In addition, the design should facilitate the reworking of cables without having to remove and re-solder their connector ends.  
       SUMMARY OF THE INVENTION  
       [0010]     The present invention concerns a stuffing tube for traversing a bulkhead with a cable and method for doing the same. The cable stuffing tube can accommodate several types of cables, such as power cables, RF communication cables, and data cables. The stuffing tube can also accommodate a plurality of cables of different shapes and cross-sectional areas. The cable stuffing tube comprises a rigid peripheral wall that can enclose an internal area. The rigid peripheral wall can further comprise a flange that outwardly extends from an outer surface of the rigid peripheral wall. A core can be formed of a resilient material that can be disposed within the internal area. The core can have a first and second opposing faces that are spaced apart. The cable stuffing tube can include one or more cable bores that can each have different cross-sectional profiles.  
         [0011]     The invention can further include a compression device. The compression device can be at least partially disposed within a control bore of the core. The compression device can selectively vary an application of a compressive force to the resilient material. The compression device can further comprise a system of opposing flanges that are separated by the core. The flanges outwardly extend from a longitudinal axis of the compression device.  
         [0012]     The invention can further include at least a first cable bore. The cable bore can be exclusive of the control bore formed in the core. The first cable bore can extend between the first and the second opposing faces. The compressive force can produce a dimensional variation in a cross-sectional profile of the first cable bore. According to one alternative, a pierceable cable bore membrane can be disposed within and transverse to a longitudinal axis of the first cable bore. According to another alternative of the invention, the first cable bore can have a cross-sectional profile that is substantially circular in shape.  
         [0013]     A gap can be formed along a peripheral wall that defines the first cable bore. The gap can extend generally in a direction between the first and second opposing faces. A gap width can be variable responsive to the compressive force. In particular, the compressive force can produce a reduction in the gap width, as well as a reduction in the cross-sectional area of the first cable bore.  
         [0014]     According to yet another embodiment, the stuffing tube can be comprised of a resilient material that is positioned between two opposing flanges. The cable stuffing tube can further include a rigid peripheral wall that is formed around an outer surface of the resilient material. A first cable bore can define an opening that extends through the resilient material. A compression device can include a system of opposing flanges. The compression device can selectively apply a compressive force to the resilient material by varying the distance between the opposing flanges. The compressive force can vary a cross-sectional profile of the first cable bore to engage a peripheral portion of a cable where it passes through the first cable bore. Moreover, a seal can be formed between an interior wall of the first cable bore and a periphery of the cable.  
         [0015]     The cross-sectional profile of the first cable bore can be designed to accommodate a particular size cable. In addition, the cross-sectional profile can be selected to be larger than a standard cable end connector for the selected cable when there is no compressive force being applied to the resilient material. The invention can further include a gap having a predetermined width defined along a wall of the first cable bore. The gap can be variable responsive to the compressive force. According to another embodiment, the cable stuffing tube can include a pierceable membrane within the first cable bore. One or more cables can be positioned within one or more cable bores extending through the resilient material. The second cable bore can have a different cross-sectional profile as compared to the first cable bore. The compression device can concurrently vary a cross-sectional profile of each cable bore. The cable bore can be responsive to the compressive force to engage a peripheral portion of each cable where the cable passes through the cable bore.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1  is a perspective view of a cable stuffing tube that is useful for understanding the invention.  
         [0017]      FIG. 2  is a front view of the cable stuffing tube that shows the cable stuffing tube in its uncompressed position.  
         [0018]      FIG. 3  is a front view of the cable stuffing tube that shows the cable stuffing tube in its compressed position.  
         [0019]      FIG. 4  is a cross-sectional view of  FIG. 2  along the line  4 - 4  that shows the cable stuffing tube in its uncompressed position.  
         [0020]      FIG. 5  is a cross-sectional view of  FIG. 3  along the line  5 - 5  that shows the cable stuffing tube in its compressed position.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]     A stuffing tube assembly  100  shown in  FIGS. 1-5  can include: a peripheral wall  101 , a core  102 , and a compression device  103 . The peripheral wall  101  can at least partially enclose the core  102  as shown. The core  102  can be formed of a resilient material that is comprised of a system of bores. For example a control bore  401  and at least one cable bore  112  can be provided. The system of bores,  401  and  112  define an opening extending through the resilient material between a first and second face ( 402  and  403 , respectively), of the core  102 . Portions of the compression device  103  can be partially disposed within the control bore  401  of core  102 . The compression device  103  can vary an application of a compressive force to the resilient material of the core  102 .  
         [0022]     The peripheral wall  101  can have any shape and can be comprised of an inner and outer surface ( 104  and  105 , respectively). The outer surface  105  can be sized and shaped to fit a bulkhead opening of a vehicle or shelter. The inner surface  104  can be sized and shaped to accommodate the size and shape of the core  102 , such that a seal can be formed between the inner surface  104  and surface portions of an outer periphery  106  of the core  102 . The peripheral wall  101  can include a flange  107  that extends outwardly from the outer surface  105  thereon. The flange  107  can be configured for securing the stuffing tube assembly  100  to the bulkhead. Moreover, the flange  107  can form a seal when secured to the bulkhead. In  FIGS. 1-5 , a plurality of screws  113  can be used to secure the stuffing tube assembly to the bulkhead by passing the screws  113  through holes bored on the flange  107 . However, the invention is not limited in this regard. Other ways to secure the stuffing tube assembly can include soldering the flange to the bulkhead, or employing other fastening methods.  
         [0023]     In  FIG. 1 , the peripheral wall  101  is shown to be substantially cylindrical in shape, although it should be understood that the invention is not limited in this regard. For example, other shapes for the peripheral wall  101  can include tubular or parallelepiped shapes. The size and shape of the peripheral wall  101  is designed to enclose an internal area  108  defined by the size and shape of the core  102 . The internal area  108  can include a longitudinal axis  109  that extends perpendicularly to an exterior and interior cross-sectional opening ( 110  and  111 , respectively). The inner surface  104  is shown in  FIG. 1  to be cylindrical and smooth, in accordance with the smooth surface portions of the outer periphery  106  of the cylindrical core  102 . However, the invention is not limited in this regard and may include other types of surface types, so long as a seal is formed between inner surface  104  and surface portions of an outer periphery  106  of the core  102 .  
         [0024]     The peripheral wall  101  can be formed of a rigid material in order to limit the deformation of the core  102 . There are several reasons for forming the peripheral wall of a rigid material. The inner surface  104  of the peripheral wall  101  should be rigid so as to provide a counteracting force directed against the varying compression force that causes the resilient material to push against the inner surface  104  of the peripheral wall  101 . In addition, the rigidness of the peripheral wall helps to maintain the aforementioned seals. The flange  107  can also be formed of a rigid material so as to securely mount the peripheral wall  101  to the bulkhead. Moreover, both the peripheral wall  101  and the flange  107  can be formed of a corrosion-resistant material to weather any harsh environmental conditions. Examples of rigid and/or corrosion-resistant materials include, but are not limited to, iron, aluminum, nickel, copper, and alloys thereof such as stainless steel and brass.  
         [0025]     The core  102  can be disposed within the internal area  108  formed by the inner surface  104  of the peripheral wall  101 . The length of the core  102  can extend in a direction defined by the longitudinal axis  109 . The core  102  can be sized and shaped to fit within the internal area  108 , such that a seal can be formed between the inner surface  104  and the surface portions of the outer periphery  106  of the core  102 . In view of the foregoing, any number of core shapes and can be used. Such core shapes include, but are not limited to cylindrical, tubular, and parallelepiped shapes.  FIG. 1  shows a circular cross-sectional area of a cylindrically shaped core  102 . However, the invention is not limited in this regard. Other shapes can be used so long as the core  102  can securely fit within the internal area  108  defined by the peripheral wall  101 , and a seal can be formed between the inner surface  104  and the surface portions of the outer periphery  106  of the core  102 . The core  102  can be formed of any suitable resilient material. Examples of such resilient material can include, but are not limited to, rubber/elastomer types such as polyurethane rubber, buna rubber, Viton® rubber, neoprene™, EPDM rubber, silicone RTV, fluorosilicone rubber, and other polymer materials.  
         [0026]     Referring to  FIGS. 2 and 4 , a system of bores ( 401  and  112 ) can be formed through the core  102  and can be aligned with the longitudinal axis  109 . One such type of bore, a control bore  401 , can be designed to accommodate portions of the compression device  103  disposed therein. Another type of bore, a cable bore  112 , can be designed to accommodate portions of a particular size cable extending between the first and second opposing faces ( 402  and  403 , respectively) of the core  102 . The cross-sectional profile areas of both the control bore  401  and the cable bore  112  can be of any shape, and are not limited to circular cross-sections as shown in the  FIGS. 1, 2 , and  4 . Examples can include elliptical and polygonal cross-sectional shapes. A gap  201  can be formed along a peripheral wall of a cable bore  202  and can extend parallel to the longitudinal axis  109 . The width of the gap  201  can vary depending upon the compressive force intended to be applied to the core  102  by the compression device  103 , and the amount of variation desired in the cross-sectional profile area defined by the cable bore  112 .  
         [0027]     When the core  102  is in an uncompressed position, as shown in  FIGS. 2 and 4 , the width of the gap  201  and the cross-sectional profile area of the cable bore  112  can both be at a maximum. This cross-sectional profile area can be selected to be larger than a standard cable connector for the cable. This allows a particular size cable to pass through the cable bore  112  without having to remove its cable connector. However, when the core  102  is in a compressed position, as shown in  FIGS. 4 and 5 , the width of the gap  201  and the cross-sectional profile area of the cable bore  112  can be reduced responsive to the compressive force being applied to the core  102 . As this narrowing occurs, a seal is formed between the peripheral wall of the cable bore  202  and a peripheral surface portion of the cable. In order to form the aforementioned seal, the width of the gap  201  must close completely.  
         [0028]     Although the cable bores  112  shown in  FIGS. 1-5  show identical cross-sectional profile areas to accommodate cables of equal sizes, the invention is not limited in this regard. The stuffing tube assembly  100  can be adapted to accommodate one or more cables having different cross-sectional areas. This can be achieved by forming one or more cable bores  112  with different respective cross-sectional profile shapes and sizes. In addition, the relative placement of the control and cable bores represented in  FIGS. 1-5  need not be placed in such an arrangement. For example, the control bore  401  is not required to be centrally placed, and can be positioned in other areas of the core  102 . Moreover, the cable bores  112  do not have to be evenly spaced around the periphery of the control bore as is shown in  FIGS. 1-5 . Instead, a wide variety of bore placement configurations are possible without affecting the functionality of the invention.  
         [0029]     According to one embodiment, a pierceable membrane  419  can be disposed within one or more cable bores  112  when the particular cable bores are not used. Moreover, the pierceable membrane  419  can be disposed transverse to a longitudinal axis of the first cable bore that is aligned with the longitudinal axis  109 . The membrane  419  can be formed from a resilient material similar to the resilient material used to form the core  102 . Such resilient material can include, but is not limited to, rubber/elastomer types such as polyurethane rubber, buna rubber, Viton® rubber, neoprene™, EPDM rubber, silicone RTV, fluorosilicone rubber, and other polymer materials. The membrane  419  can be designed to form a seal around the peripheral wall  304  of the cable bore  112 . When the particular cable bore  112  is ready for use, the membrane  419  can be pierced to allow a cable with its corresponding cable end connector to extend through the cable bore  112 . It should also be understood that in order for a cable and its connector to pass through a membrane-pierced cable bore  112 , the core  102  should remain in an uncompressed position.  
         [0030]     Referring to  FIGS. 4 and 5 , the compression device  103  is shown in an uncompressed position and a compressed position, respectively. In the embodiment shown, the compression device  103  includes a thumbscrew  404  and a receiving member  405 . The thumbscrew  404  can be further comprised of a key handle  406 , a thumbscrew flange  407 , a thumbscrew cylinder  410 , a thumbscrew unthreaded portion  408 , and a thumbscrew threaded portion  409 . The key handle  406  can be mechanically coupled to the thumbscrew unthreaded portion  408 , which is in turn coupled to both the thumbscrew flange  407  and the thumbscrew threaded portion  409 . The thumbscrew flange  407  can extend outwardly from the thumbscrew unthreaded portion  408  that is aligned with the longitudinal axis  109 . Moreover, the thumbscrew flange  407  can be disposed on a portion of the first face  402  of the core  102 . The thumbscrew threaded portion  409  can be partially disposed within the control bore  401 .  
         [0031]     The receiving member  405  can be further comprised of a flanged end  413  and a threaded receiving cylinder  414  that threadingly engages the thumbscrew threaded portion  409 . The flanged end  413  of the receiving member  405  can extend outwardly from the threaded receiving cylinder  414  that is aligned with the longitudinal axis  109 . The flanged end  413  of the receiving member  405  can be disposed on the second face  403  of the core  102 . The flanged end  413  of the receiving member  405  and the thumbscrew flange  407  can form a system of opposing flanges separated by the core  102 . The threaded receiving cylinder  414  can be at least partially disposed within the control bore  401 . The threaded receiving cylinder  414  of the receiving member  405  can be further comprised of an outer cylindrical surface  415  and a threaded inner surface  416 . The outer cylindrical surface  415  can be smooth and have a circular cross-sectional profile. However, the invention is not limited in this regard. An alternative cross-sectional profile to the outer cylindrical surface  415  can be that of a star-shaped cross-sectional profile. The star-shaped outer surface can be interlockingly mated with a peripheral wall of the control bore  417  having a star-shaped cross-sectional profile. This alternative can avoid any rotation of the receiving member  405  when engaged with the thumbscrew  404 . It should be noted, however, that the structure of the compression device  103  is not limited to what is shown in  FIGS. 1-5 . For example, the compression device  103  may instead be comprised of an internally threaded thumbscrew cylinder that can threadingly engage an externally threaded receiving cylinder.  
         [0032]     Upon rotation of the key handle  406  of the thumbscrew  404  and relative advancement by the thumbscrew threaded portion  409 , the core  102  can be compressed using the system of opposing flanges ( 407 ,  413 ) disposed on opposing faces of the core  102 . As the thumbscrew threaded portion engages the threaded receiving cylinder  414 , the opposing flanges ( 407 ,  413 ) move toward each other. As the core  102  is compressed by its interaction with the opposing flanges and the rigid inner surface  104  of the peripheral wall  101 , the resilient material becomes distorted. This distortion results in the narrowing of the gap  201  and cross-sectional profile area of the cable bore  112 . In order to form a form a seal around the peripheral portion of the cable disposed within the cable bore  112 , the gap  201  must close completely during the compression of the core  102   
         [0033]     While the specific embodiments of the invention have been disclosed, it will be appreciated by those skilled in the art that various modifications and alterations to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof.