Abstract:
High-power coaxial signal lines, as used for example in television transmitters, employ patch panels with coaxial connections typically 7 cm to 30 cm in diameter to permit rerouting of signals. Like smaller patch panels, these use U-shaped coaxial links; rigid U-links for this application may be a meter between centers and weigh many kilograms. A patch panel handle and latch mechanism includes a gripping handle element integral with a latching element, the combination of which permits the user to grasp a pair of handles, release the latches retaining a U-link, remove the U-link from its position on the patch panel, and reposition the U-link without altering grip. Unlike previous designs, the novel handle/latch mechanism avoids hammers and clamps, as well as avoiding grasping large, fragile, possibly hot or dirty equipment, allowing the task to be performed with integral handles.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to patch panels. More particularly, the present invention relates to manually operated coaxial line patch panels for radio frequency signal switching.  
       BACKGROUND OF THE INVENTION  
       [0002]     Patch panels are used in many industries for distribution and redirection of electrical signals. In the broadcast industry, coaxial lines in the range from a few centimeters to several decimeters in diameter carry radio frequency signals from amplifiers and transmitters to broadcast antennas atop towers that may stand up to half a kilometer or taller, as well as to non-broadcast loads. Such transmitters and coaxial lines may be highly reliable, but failure modes exist, and, as with virtually all electronic equipment, provisions may preferably be made for fault analysis requiring disassembly.  
         [0003]     Typical patch panels for the broadcast industry usually consist of coaxial ports connected to typically large, rigid, coaxial jumpers, the ends of which are fastened to their respective ports with nuts and bolts to form flanged assemblies, with collapsible finger structures on the ports deflected inward by clamps onto raised ridges on the jumpers, with which ridges grooves in the finger structures interlock, or with other attachment devices achieving robust, low-loss joints. The jumpers are typically referred to in the industry as U-links.  
         [0004]     The insertion and removal of fittings so restrained is time consuming, requires in many cases considerable physical effort, and can result in significant stress to the U-link and other patch panel components.  
         [0005]     Accordingly, it is desirable to provide a patch panel apparatus and method that allows a single user to readily and reliably redirect high power radio frequency signals without exerting significant physical effort and without applying significant stress to the patch panel.  
       SUMMARY OF THE INVENTION  
       [0006]     The foregoing needs are met, to a great extent, by the present invention, wherein in one aspect an apparatus and method are provided that in some embodiments allows a single user readily to grasp, unlock, disengage, move, reengage, and positively lock the elements of a patch panel and U-link assembly for rigid coaxial cable in diameters from a few centimeters to a few decimeters.  
         [0007]     In accordance with one embodiment of the present invention, a handle and latch mechanism for a patch panel and U-link system is provided, comprising a plunging and rotating rod attached to the U-link element of the patch panel and U-link system, a latch finger at a first end of said rod, a handle at a second end of said rod, a guide mechanism to constrain the motion of said rod to a path parallel to the axis of a first end section of the U-link orthogonal to the patch panel, and a catch fitting attached to the patch panel into which said latch finger inserts.  
         [0008]     In accordance with another embodiment of the present invention, a handle and latch mechanism for a mated patch panel and U-link system is provided, comprising means for urging the U-link into contact with the patch panel, means for latching the U-link to the patch panel, means for releasing the U-link from contact with the patch panel, and means for gripping the U-link without changing hand placement from that required for latching and releasing the U-link.  
         [0009]     In accordance with yet another embodiment of the present invention, a method for attaching, holding, and releasing a signal path linking component from a radio frequency signal path comprises urging the linking component into a position where it can complete a portion of a signal path, latching the linking component for indefinite situation at the location where urged, reversibly releasing the linking component from the latched condition, and grasping the linking component for disassembly and transport.  
         [0010]     There have thus been outlined, rather broadly, certain embodiments of the invention, in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.  
         [0011]     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 and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.  
         [0012]     As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is an illustration of a perspective view of an exemplary patch panel, U-link, and latch mechanism according to this invention.  
         [0014]      FIG. 2  is an illustration of a closeup view of an exemplary latch mechanism of  FIG. 1 .  
         [0015]      FIG. 3  is an illustration of an exemplary eight-port patch panel fully populated with U-links.  
         [0016]      FIG. 4  is an illustration of an exemplary four-port panel. 
     
    
     DETAILED DESCRIPTION  
       [0017]     The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout.  
         [0018]      FIG. 1  is an illustration of an embodiment of the present inventive apparatus and method. A patch panel  10  has a first U-link  12  inserted into a first port  14  and a second port  16  and retained by a first latch/handle  18  and a second latch/handle  20 . The first U-link  12  has an integral fitting  22  that permits the U-link to change length sufficiently to accommodate at least small spacing variations between pairs of ports  14  and  16 ,  24  and  26 , etc., as well as providing one of several possible mechanisms for assembling a U-shaped coaxial link. Each port, such as  24 , has an outer coaxial contact  28  and an inner coaxial contact  30 . The first U-link  12  has outer and inner contacts that mate with those of the ports, and insulating features that keep the spacing between the outer and inner conductors of the first U-link  12 , and thus the electrical impedance at each joint, as uniform as practicable.  
         [0019]      FIG. 2  is an expanded illustration of the patch panel of  FIG. 1 , showing the parts of a latch apparatus in greater detail. A support  32  is attached to a second end  34  of the first U-link  12 . The support  32  may be affixed to the first U-link  12  by welding, riveting, and other durable securing methods suitable to assemblies of the materials used. For example, since the first U-link  12  outer conductor material is commonly aluminum, and the support  32  may likewise be aluminum, welding may be practical. A support  32  made from fiberglass, another possible material, can be held in place by rivets, by epoxy or similar adhesives, or by a perimeter clamp band.  
         [0020]     A proximal guide  36  and a distal guide  38  are attached to the support  32 ; captured in a proximal guide hole  40  and a distal guide hole  42  is a rod portion  44  of the second latch/handle  20 . The guide holes  40  and  42  shown have arcuate gaps  46  closed with pins  48  instead of having, for example, complete, circular guide holes. This guide hole assembly eases installation and replacement of the latch/handle  20  by removal of the pins  48 . The rod  44  is formed into a handle  50  at the end distal to the patch panel  10 . The handle  50  can be formed of a material and size that can make it sufficiently sturdy that the U-link can be lifted, carried, twisted, worked to compensate for binding misalignment, and otherwise exercised without appreciable permanent deformation to the handle  50 .  
         [0021]     The rod end proximal to the patch panel  10  in the preferred embodiment is shown to be bent into a latch finger  52  at roughly a right angle to the central section of the rod  44 , which latch finger  52  is thus roughly parallel to the surface of the patch panel  10 . A catch fitting  54  is sized and located to accept the latch finger  52 . The catch fitting  54  can have a bearing surface  56  against which the latch finger  52  rests that has a retention pocket  58  to urge the latch finger  52  to remain engaged. The retention pocket  58  can take the form of a bent-down tip, a groove set back from the tip, or another configuration that tends to retain the latch finger  52 .  
         [0022]     To further urge the latch finger  52  to remain engaged, the portion of the rod  44  near the distal guide  38  can have a stop  60  fastened to the rod  44 , a helical compression spring  62  pressing outward against the stop  60  and the outer guide  38 , and inward against a thrust washer  64 , which parts can apply continuous pressure urging the rod  44  away from the patch panel  10  surface. It has been demonstrated that a sufficiently tight radius of bend  66  in the rod  44  where forming the handle  50  can cause a stop  60  with a close-fitting center hole to bind at the bend  66 , permitting the stop to function without recourse to drilling and pinning, grooving for a snap ring, welding, upset of the rod material into ears, or other retention treatments that can weaken the formed metal of the rod  44 . In order for the use of the handle bend as a part of the retention treatment to remain a net benefit, the radius of curvature of the bend  66  cannot be so tight as to weaken the rod  44  enough to degrade its mechanical strength below system needs. Alternative retention treatments can be used as long as the final strength of the mechanism meets system requirements.  
         [0023]      FIG. 3  is an illustration of a fully populated exemplary patch panel  70  with eight ports  72 - 86  and with four U-links  88 - 94  installed. The signal lines feeding the ports determine the desired connections; for a highly useful patch panel, two inputs from two transmitters, two outputs to a combiner, two return lines from the combiner, an antenna transmission line, and a connection to a high-power resistive load, known in the art as a station load, may be connected, and the layout may permit a variety of connections, such as connecting a transmitter to each of the combiner inputs, the antenna to one combiner output, and the resistive load to the other combiner output.  
         [0024]     A patch panel  70  configured to support all of these configurations may need to have each of the U-links  88 - 94  oriented to connect a first port to any of a large number of other ports, typically limited to those uniformly surrounding the first port, and oriented at angles thereto that are multiples of 60 degrees from a reference angle. In order to use the U-links, each of the orientations can have a catch fitting  54  at any of the useful angles. The shown ports  72 - 86  have mounting bolts  96  every 30 degrees, allowing the holes admitting the mounting bolts  96  to be used to secure the catch fittings  54 . For ports with numbers of mounting bolts  96  different from those shown, and thus at different incremental angles than the 30 degrees of a 12-bolt pattern, catch fittings  54  with longer upper surfaces can be positioned to capture latch fingers  52  at locations away from the mounting holes. As shown in  FIG. 2 , a catch fitting  54  can include a bevel  68  on its upper surface to deflect rather than stop a slightly misaligned latch finger  52  during assembly, easing the assembly operation.  
         [0025]     Coaxial signal ports  72 - 86 , fed to the panel  70 , for example, from the back of the panel, can be positioned so that equal-length, front-mounted, rigid U-links  88 - 94  can connect any first port to any second port that requires such a connection. An example of a useable set of connections is port  74 , which, possibly using pairs of permanent elbows on the back of the panel to complete some circuits, can connect to any of the ports  72 ,  80 ,  82 , or  76 . Retention of the U-links to connect pairs of desired ports may be accomplished using spring-loaded assemblies of handles, fasteners, guides, and receptacles. The spring-loaded retention assemblies further permit rapid release of the retention fittings and permit the user to grasp, remove, carry, reinstall, and lock in place a U-link while retaining a grasp on the assemblies.  
         [0026]      FIG. 4  is an illustration of an exemplary four-port patch panel  100 , which can be used to allow two signals to pass to either of two loads, such as to connect the normal output of a combiner to an antenna using a first U-link  102 , and the off-frequency output of that combiner to the station load using a second U-link  104 , or to send the normal output to the station load, such as for testing, while the off-frequency output is connected to the antenna, by repositioning the U-links  102  and  104  orthogonally to the positions shown. It may be observed that the U-links  102  and  104  in  FIG. 4  are constructed using a multiplicity of 45-degree bends rather than the two 90-degree bends shown in the U-links  88 - 94  in  FIG. 3 . Such variations are minor considerations regarding latch/handle  18  design. It may further be observed that the mounting bolt pattern in  FIG. 4  places bolts  96  at 45-degree increments, which is suitable for the design shown.  
         [0027]     Although an example of the exemplary latch mechanism is shown in use on a patch panel, as illustrated in  FIGS. 1-4 , it will be appreciated that the exemplary latch mechanism can be used with other items. Also, although the exemplary latch mechanism is useful to support, retain, and provide a handle for carrying patch panel U-links for high-power coaxial lines in radio frequency broadcast applications, it can also be used to support, retain, and carry other awkward items, such as, for example, waveguide elements, hot-pluggable electronic devices, food service wares, and other electronic and non-electronic apparatus generally stable while in place but standing to benefit from simple retention hardware designs that add convenience to lifting and orienting tasks.  
         [0028]     Several details of the preferred embodiment are according to design preference. For example, the latch/handles  18  and  20  shown in  FIGS. 1-4  are formed from single pieces of rod material. Simple handles with a single bend to afford an L shape may be suitable for some applications, particularly for small, low-mass systems. More constructed handles are also feasible, for example with a welded-on T made from the same rod material in place of the bent D shape  50  shown in  FIG. 2 . Likewise, other materials and forms for the handle end may be practical in other applications. A cushioned grip may be added. At the catch fitting  56  end shown in  FIG. 2 , the L bend  52  of the preferred embodiment may be replaced by fabricated, forged, or welded protrusive fittings that may permit a plurality of catch shapes to be used. The guides  36  and  48  used can be made in two fabricated parts instead of a groove  46  barred with a pin  48 ; this may be preferred if it can provide tighter positioning precision, improved appearance, greater strength, lower cost, or other benefit. The catch fitting  56  similarly may be fabricated from a solid block from which only the interference materials are removed in order to maximize strength within a particular size of catch fitting  56 , or may be extruded or bent to shape. The tensioning spring stop  60  can be attached to the rod  44  using a variety of methods and materials, such as grooves or holes in the rod, braising or welding of the stop  60  to the rod  44 , or affixing of a drilled block on the rod  44 , which block extends to the distal bend  66  to avoid weakening the rod.  
         [0029]     The mechanism can be formed as a stationary handle extending as a rod insertable into a capture mechanism, where a plunger within or alongside the rod forces at least one locking ball or pin outward to secure the rod in the capture mechanism, and a trigger or button on the handle may be pulled or pushed against a spring to release the ball or pin and allow the U-link to be pulled free of the patch panel.  
         [0030]     The mechanism of the rod can be fabricated from a slotted tube or from a block of material, with the guides formed as pins riding within and largely surrounded by the material of the rod.  
         [0031]     The material of the entire latch mechanism can be any metallic or nonmetallic material or combination of materials of sufficient strength and stiffness to be used as a support handle as well as a locking mechanism. Tradeoffs between manufacturability, durability, cost of materials, dissimilar metals promoting corrosion, and other issues may be considered.  
         [0032]     It should be appreciated that embodiments of this invention, among other capabilities, allow a single user to pick up and install a U-link of comparatively large size without needing to change grip or use tools. These embodiments afford further isolation of the user from dust, grease, or high temperatures that may make grasping the body of the U-link undesirable, and tends to prevent misadventures such as: squeezing or dropping the U-link, which may dent or otherwise distort its thin wall material, thereby introducing reflective transmission losses.  
         [0033]     The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to that fall within the scope of the invention.