Abstract:
A cable carrier apparatus has a bracket having a vertical mounting surface interface for mounting securely to a post, wall, or other stable support, and a horizontal portion, a first roller rotatable on a vertical post anchored to be stationary relative to the frame bracket, with the first roller positioned below the horizontal portion of the bracket, the first roller having a circumferential groove symmetrical around an axis of the post and about a horizontal plane, the groove having a cross-section with a radius describing a portion of a semicircle, but less than a full semicircle, and a second roller matching the first roller and rotatable on a second post having an axis, the second roller mounted to be translatable against spring force away from the first roller, wherein a traveler translating on a cable being held between the two rollers traverses through the rollers, maintaining the cable between the rollers.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
       [0001]    The present invention is in the technical area of cable runs, and pertains more particularly to support devices for configuring cable runs and passing travelers connected to loads. 
       2. Description of Related Art 
       [0002]    It is well known in the arts to suspend a cable from one anchor point to another, and to harness a mechanical traveler to such a cable, the traveler enabled to slide or roll along the suspended cable, connected to a load of some sort intended to be supported or constrained by the cable in a path defined by the cable between the anchor points. Dog runs are one simple example. Another example is safety equipment for such as steel workers in construction. 
         [0003]    A problem with such cable runs is that they are typically limited to the cable length between the anchor points. It is known to provide a plurality of anchor points, and to support cable from one to another and another, in a pattern, but typically one must disconnect the mechanical traveler from one cable and reconnect to another, to move the connected load to the next cable run. This process is labor intensive at best, and in the circumstance of safety equipment can be dangerous as well, as a worker disconnects a harness from one run and reconnects to another. 
       BRIEF SUMMARY OF THE INVENTION 
       [0004]    In one embodiment a pass-through cable carrier apparatus is provided, comprising a frame bracket having a vertical mounting surface interface for mounting securely to a post, wall, or other stable support, and a horizontal portion, a first roller rotatable on a first vertical post anchored to be stationary relative to the frame bracket, with the first roller positioned below the horizontal portion of the frame bracket, the first roller having a first circumferential groove symmetrical around a central axis of the post and about a horizontal plane, the groove having a cross-section with a radius describing a substantial portion of a semicircle, but slightly less than a full semicircle, and a second roller matching the shape and dimensions of the first roller and rotatable on a second vertical post having a central axis, the axes of the first and second vertical posts lying in a plane at a right angle to the mounting surface of the frame bracket, the second roller mounted to be translatable against spring force away from the first roller. 
         [0005]    In one embodiment the second vertical post is mounted in a translatable carriage guided by shafts in bores in a guide block, wherein the translatable carriage is urged toward the first roller by one or more springs. Also in one embodiment the second vertical post is mounted at an upper end pivotally at a free end of a horizontal cantilever arm mounted at an opposite end pivotally at a position such that rotation of the cantilever arm about the pivot causes the second roller to move away from the first roller. Also in one embodiment the cantilever arm bears on one side against a leaf spring that urges the cantilever arm in a rotary direction to move the second roller against the first roller. In one embodiment the first and the second rollers are cylinder shapes with the grooves cut to be symmetrical about a plane orthogonal to a central axis of the cylinder, leaving cylindrical lands above and below the grooves that may bear on one another when the rollers are touching. 
         [0006]    In one embodiment the first and the second rollers are spherical shapes with the grooves cut to be symmetrical about a plane passing through a center of the spherical shape of each roller. Also in one embodiment the frame bracket has two vertical mounting surface interfaces, one on each end of the horizontal portion, extending downward from the horizontal portion, enabling mounting to a wall, post or other vertical support, with the translatable roller nearer to the vertical support, or alternatively away from the vertical support. Also in one embodiment the apparatus further comprises a traveler having a body symmetrical about a central axis, with a length and a circumference along a central portion of the length, the circumference having a radius equal to the radii of the grooves of the first and second rollers, a tapered shape from the central portion to each end of the body, a tongue extending from the central portion of the length of the body at a right angle to the central axis of the traveler, the tongue having a length along the body substantially less than the length of the central portion of the body, and a thickness substantially less than the diameter of the central portion of the body, the body further having a central bore along the axis, through which a cable passes, that also passes through the pass-through cable carrier apparatus between the rollers. And in one embodiment the traveler is urged to pass between the rollers, such that a first tapered end guides the traveler into contact with the grooves in the rollers, the rollers roll upon the traveler body when the central round portion of the traveler body is between the rollers, the traveler urges the rollers apart providing passage between the rollers for the tongue of the traveler while supporting the cable, and the tapered opposite end of the traveler body allows the rollers to close as the traveler passes through, the closed rollers capturing and supporting the cable. 
         [0007]    In another aspect of the invention a method for supporting a cable while allowing a cable traveler to pass through is provided, comprising steps of (a) mounting a pass-through cable-carrier apparatus to a post, wall, or other stable support, by a vertical mounting surface of a frame bracket having a horizontal portion extending from an upper extremity of the vertical mounting interface, the apparatus comprising a first roller rotatable on a first vertical post mounted to be stationary relative to the frame bracket, with the first roller positioned below the horizontal portion of the frame bracket, the first roller having a first circumferential groove symmetrical around a central axis of the post and about a horizontal plane, the groove having a cross-section with a radius describing a substantial portion of a semicircle, but slightly less than a full semicircle, and a second roller matching the shape and dimensions of the first roller and rotatable on a second vertical post having a central axis, the axes of the first and second vertical posts lying in a plane at a right angle to the mounting surface of the frame bracket, the second roller mounted to be translatable against spring force away from the first roller, (b) passing a cable through an opening formed by the grooves of the first and second rollers in contact, (c) passing the cable through a bore through the length of a cable traveler having a body symmetrical about a central axis of the bore, with a length and a circumference along a central portion of the length, the circumference having a radius equal to the radii of the grooves of the first and second rollers, a tapered shape from the central portion to each end of the body, a tongue extending from the central portion of the length of the body at a right angle to the central axis of the traveler, the tongue having a length along the body substantially less than the length of the central portion of the body, and a thickness substantially less than the diameter of the central portion of the body, and (d) causing the traveler to pass between the rollers, such that a first tapered end guides the traveler into contact with the grooves in the rollers, the rollers roll upon the traveler body when the central round portion of the traveler body is between the rollers, the traveler urges the rollers apart providing passage between the rollers for the tongue of the traveler while supporting the cable, and the tapered opposite end of the traveler body allows the rollers to close as the traveler passes through, the closed rollers capturing and supporting the cable after the traveler passes. 
         [0008]    In one embodiment the method further comprises a step mounting a plurality of pass-through cable carrier apparatuses in a pattern to a plurality of stable supports, the pass-through apparatuses spaced apart in a non-linear pattern, anchoring the cable to fixed anchors at opposite ends of the cable, and passing the traveler along the cable through individual ones of the pass-through cable carrier apparatuses. Also in one embodiment individual ones of the pass-through cable carrier apparatuses are mounted to have the translatable roller nearer the stable support, or away from the stable support, as needed to provide for tension on the cable without tending to urge the roller apart. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0009]      FIG. 1  is a side elevation view of a pass-through cable carrier in an embodiment of the invention. 
           [0010]      FIG. 2  is the side elevation view similar to  FIG. 1  illustrating the rollers separated to a maximum extent in an embodiment of the invention. 
           [0011]      FIGS. 3 a , 3 b  and 3 c    illustrate a cable traveler in an embodiment of the invention. 
           [0012]      FIG. 4  illustrates a cable run with multiple pass-through carriers in an embodiment of the invention. 
           [0013]      FIGS. 5 a , 5 b , 5 c , 5 d    illustrate how the traveler riding a cable interacts with a pass-through carrier according to an embodiment of the invention. 
           [0014]      FIG. 6 a , 6 b , 6 c    illustrate a pass-through cable carrier in another embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0015]      FIG. 1  is a side elevation view of a pass-through cable carrier  100  in an embodiment of the invention. Cable carrier  100  is supported by an external frame  101  bolted typically by conventional fasteners  112  to a structure  102 , such as a post, pole, wall or other stable structure. A first bracket  103  serves as support for a roller  103  mounted above and below by a shaft and bearings  107 , such that the roller may freely rotate about its longitudinal axis. Roller  103  has a groove  113  that is circular in shape, but describes only a major portion of a circle, as is described below in more detail. 
         [0016]    A second bracket  106  serves as support for a second roller  104  that has the same shape and dimensions as the first roller  103 , and is supported on a shaft and bearings  107  as is roller  103 . In the circumstance illustrated in  FIG. 1  rollers  103  and  104  are in contact. Bracket  106  has two or more shafts  109  extending in a direction at a right angle to the axes of rollers  103  and  104 . In this particular embodiment there are four shafts  109  arranged in a rectangular pattern. Shafts  109  slip fit into matching bores in a guide block  108  such that bracket  106  may translate to a limited extent in the direction of shafts  109 . In  FIG. 1  guide block  108  is shown in section through two of the four bores for shafts  109 . 
         [0017]    Each shaft  109  has a portion  114  of lesser diameter than the maximum shaft diameter, such that a strong compression spring  110  may be located around the lesser-diameter extension. Compression springs acting on all of the shafts  109  urge bracket  106  and hence roller  104  toward roller  103  until contact is made. By managing the length and spring rate of springs  110 , the force applied to roller  103  by roller  104  may be controlled. 
         [0018]    In  FIG. 1  it may be seen that, with bracket  106  urged by springs  110  to contact roller  103  by roller  104 , there is a space of dimension “d” between the end of shafts  109  and the depth of the bores within which the shafts are constrained and guided. This dimension limits the distance roller  104  may be withdrawn from roller  103 . The significance and purpose of this limitation is made clear in further figures and description below. 
         [0019]      FIG. 2  is the side elevation view similar to  FIG. 1  illustrating the rollers separated to a maximum extent in an embodiment of the invention. The separation is accomplished in this example by moving a traveler  115 , having a round cross-section through the rollers. Traveler  115  has a circular cross-section of a maximum radius equal to the radius of the grooves  113  in  FIG. 1  for rollers  103  and  104 , and in this example a through hole  116  of a lesser diameter. Traveler  115  is described in further detail, and its use is described, as traveler  301  in  FIGS. 5 a , 5 b  and 5 c    below. 
         [0020]    It was described above in regard to  FIG. 1  that grooves  113  describe less than a full half-circle. The difference in this example is just sufficient that fully round traveler  115  causes rollers  103  and  104  to separate by dimension “d”, which is the distance described in  FIG. 1  to which separation is limited by the length of shafts  109  and the bores that guide the shafts in guide block  108 . The amount of separation may be very small, or considerably larger, depending on design and scale of the pass-through carrier. 
         [0021]      FIG. 3 a    is a side elevation view of a cable traveler  301  in an embodiment of the invention, and  FIG. 3 b    is an end view of cable traveler  301  of  FIG. 3 a   . Cable traveler  301  comprises a body  302  having a maximum diameter D for a portion D 1  of length L centered on the length. Traveler  301  in this example is the same as traveler  115  of  FIG. 3 . A connector tongue  303  extends dimension D 2  from body  302  centered on the length of body  302 , and has a hole  304  near the end away from the traveler body, for connecting to a harness, a dog leash, or other device that may be enabled to follow a cable run with the traveler. In other embodiments the connection from tongue  303  need not be by a hole  304 , but could be any of a number of fasteners and techniques. A bore  306  on the long axis of the traveler body is for following cable  305 , which may be a metal cable comprising braided strands, a cord, a rope, or other material. Bore  306  is somewhat larger in diameter than cable  305 , so the traveler may easily travel along the cable, supported at intervals by pass-through carriers of the sort described with reference to  FIGS. 1 and 2 . 
         [0022]      FIG. 3 c    illustrates an implementation in which tongue  303  is engaged by a pivot at point  307  to allow the tongue to assume an angle other than 90 degrees with the body of the traveler. For example the tongue may pivot forming an angles less than 90 degrees in a direction of travel of the traveler  301 . The skilled person will understand that this may be accomplished in a variety of ways. 
         [0023]      FIG. 4  illustrates a plan view from above of a cable run using four pass-through cable carriers as described relative to  FIGS. 1 and 2 . Cable  305  is anchored securely on opposite ends and supported by pass-through carriers  100  labeled A, B, C and D. As seen in the layout, it is not necessary that the cable direction be constant. the cable can change direction between points A, B, C and D. A traveler  301  as described with reference to  FIG. 3  is shown riding the cable between the pass-through carriers at A and B. The traveler moves along the cable between pass-through carriers, and through the pass-through carriers, by virtue being pulled along by a tethered person or animal in some cases. In other uses pass-through carriers and travelers in embodiments of the invention may be used for many purposes, such as, for example, overhead conveyors, cable cars, and other heavy-duty applications, in some of which the traveler may be powered to move along the cable. 
         [0024]      FIG. 5   a, b, c  and  d  illustrate how the traveler riding a cable interacts with a pass-through carrier according to an embodiment of the invention. In  FIG. 5 a    traveler  301  has entered a pass-through carrier between rollers  103  and  104 . Dotted circles  501  indicate the minimum diameter of each roller at the root of the groove in each roller. The tapered shape of traveler  301  guides the traveler between the rollers until the point shown where the diameter of the traveler is just large enough to touch the both rollers. At this point tongue  303  has not reached the rollers. 
         [0025]      FIG. 5 b    illustrates the traveler has moved into the pass-through carrier to where the max diameter of the traveler has pushed roller  104  against the springs and opened a passage between the rollers for tongue  303 , which may be seen just entering the area between the rollers. 
         [0026]      FIG. 5 c    illustrates a further movement of the traveler to where the traveler is one-half way through the rollers, and tongue  303  is moving through the gap between the rollers caused by the traveler opening the rollers. 
         [0027]      FIG. 5 d    illustrates the traveler having moved through the rollers to a point where the rollers are allowed to close to contact, and tongue  303  has cleared the rollers. The traveler may now move along the cable to the next pass-through carrier point. 
         [0028]    The actual interaction between the traveler and the rollers is over a short distance, and in contact with the traveler, the rollers rotate rather than dragging on the traveler, which action facilitates the forward movement of the traveler. When the traveler passes through, the springs snap the rollers closed again, and help to push the traveler out of the pass-through carrier along the cable. 
         [0029]      FIGS. 6 a, b , and  c    illustrate a pass-through cable carrier according to another embodiment of the invention. In this example two spherical rollers  603   a  and  603   b  having grooves  605  the same as grooves  113  of rollers  103  and  104  in  FIG. 1 , are pivoted on shafts  604  beneath a horizontal portion of a frame bracket  601 . One post  604  is pivoted in the top portion of bracket  601 , and the other is pivoted at an end of a cantilever arm  606 , which is pivoted in the top portion of bracket  601  at post  610 . Arm  606  pivoting about post  610  enables roller  603   b  to move away from and toward roller  603   a . A leaf spring  607  urges arm  606  in a direction that moves roller  603   b  toward and against roller  603   a.    
         [0030]    It will be apparent to the skilled person, having read the above descriptions of the apparatus of  FIGS. 1-3 , that the apparatus of  FIG. 6 a    will operate in essentially the same manner as that of  FIG. 1-3 . In particular, referring now to  FIGS. 5 a  through 5 d   , it should be apparent that a traveler  301  moved into and through rollers  603   a  and  603   b  will cause roller  603   b  to move away from roller  603   a  against leaf spring  607 , so the opening formed by grooves  605  will define a circle the diameter of the traveler, and the traveler may pass, with the rollers rolling against the traveler. 
         [0031]    An advantage of the apparatus of  FIG. 6 a    is that it is substantially simpler and less bulky than that of  FIGS. 1-3 .  FIGS. 6 b  and 6 c    illustrate a further advantage of the apparatus of  FIG. 6 a   , which is the fact that bracket  601  may be bolted to support post or wall  102  as shown in  FIG. 6 b   , wherein roller  603   b  moves away from support  102 , and also as shown in  FIG. 6 b   , such that roller  603   b  is closer to the support post, and moves in operation toward the support post rather than away. 
         [0032]    The ability to reverse the operation of the pass-through carrier of  FIG. 6 a    allows flexibility in providing cable runs over a plurality of pass-through carriers. Referring now back to  FIG. 4 , it may be seen that the cable run shown through A, B, C and D needs to have the pass-through carriers properly oriented to be able to apply substantial tension to cable  305 . Consider the pass-through carrier at B, for example. With the cable in tension that carrier needs to have the roller to the outside (away from the post support) to be the roller that does not move, that is pivoted in the frame bracket. And the inner roller needs to be the roller that may move against spring pressure. The same is true at D, but the opposite is true at C. The interchangeable design shown as  FIGS. 6 a , 6 b  and 6 c    provide this flexibility. 
         [0033]    It will be apparent to the skilled person that there are different ways that cantilever arm  606  may be implemented, and that there are a variety of ways that spring pressure may be applied to arm  606  to bias the arm and urge roller  603   b  toward roller  603   a.    
         [0034]    The apparatus thus far described, and the traveler, are relatively light-weight implementations useful for such as safety harnesses, dog runs, and the like. It is to be understood, however, that the same and similar mechanisms may be scaled for more demanding applications, such as cable car runs, overhead commercial conveyors and much more. 
         [0035]    In one embodiment, in a more heavy-duty application, traveler  301  may be considerably larger, and may be mechanically driven along cable  305 , having drive and power elements within an outer shell that provides the tapered in and out shape and a round cross-section centrally, so the traveler opens the rollers for pass-through, which than close as the mechanically driven traveler passes through. 
         [0036]    Rollers in a pass-through cable carrier described above with reference to  FIGS. 1 through 6   c  uniformly describe a system wherein the traveler has a round cross-section orthogonal to the direction of the traveler&#39;s motion on a cable, and rollers in the pass-through carriers that present a round aspect to the traveler in interaction. The roundness, however, is not a limitation in the invention. There are a variety of other shapes that travelers and compatible rollers might exhibit. As a single example, if grooves  113  as seen in  FIG. 1  were, rather than having a circular radius, V-shaped grooves wherein opposite straight sides of the groove are at complementary angles with horizontal, so the V-shape points toward the axis of the roller, then a traveler, to be compatible, would have a square or a diamond shape in cross section, rather than round. The traveler shape would be square if the included angle of the groove were ninety degrees. 
         [0037]    Referring now to  FIG. 4 , showing a cable system comprising several pass-through carriers, it was described above that the carriers might have either the inside or the outside roller movable against spring loading, depending on which way the cable turns toward the next carrier. IN such applications it is important that the cable from end to end remain in some tension. Sagging cable between carriers might well impede proper operation. The ensure tension on the cable, one or both ends of the cable, where anchored, may be anchored with strong tension springs to keep the cable in tension. Understanding that fatigue may cause stretching over time, one or more turnbuckles or similar devices may also be incorporated in a cable system. 
         [0038]    Further to the above, in some applications the cable run may not be anchored at ends, but may be implemented as a moving cable with travelers constrained so they do not translate along the cable. IN this implementation the travelers may carry one or another of a variety of loads, such as a monorail, chairs of a ski lift, or a cable car. IN one implementation cable reels on each end may be operated to move a cable to translate the travelers through the pass-through cable carriers, or a system may have an endless aspect, so a cable run doubles back upon itself, and the cable is driven by geared or friction drives. 
         [0039]    Referring again to  FIGS. 1 and 6   a - 6   c , two different means of providing relative movement between rollers in a carrier are illustrated and described. These are but two of a wider variety of mechanical means to accomplish this purpose. In another example, rollers may be mounted on bent and folded rods much as a paint roller is mounted, so the equivalent handle of the roller may be spring loaded and pivoted to allow the captured roller to move relative to a mating roller. Further, it is not necessary or a limitation that one roller be stationary and the other movable against a spring. Both rollers may move and be spring-loaded. 
         [0040]    Further to the above, relative movement between two rollers is not the only way the pass-through of a traveler might be accomplished. In an alternative embodiment a carrier frame may be implements in a circular shape orthogonal to cable direction with a downward-facing opening for the tether of a traveler, an inside diameter of the frame being larger than the outside diameter of the traveler. In this embodiment a plurality of detents may be implemented in the inside diameter of the frame, the detents presenting spring-loaded balls toward a center of the circular aspect of the frame. The balls present a passage for the traveler with a somewhat smaller diameter than the traveler diameter, so a small retraction of the balls allows the traveler to pass. 
         [0041]    In the implementation illustrated by  FIG. 1  wherein one roller is mounted in a frame that may translate toward and away from the other roller, there are a variety of ways that the translating carriage may be constrained to translate, and in which spring pressure toward the other roller may be provided. 
         [0042]    In another alternative two rollers of either the design of  FIG. 1  or of  FIG. 6 , or other shapes, may be mounted on parallel shafts that extend to a coiled pattern above the rollers, the coils providing displacement under tension between the rollers. This mounting may be thought of as a “clothes-pin” mounting. In this embodiment the rollers do not move relative to one another with their axes parallel. In this implementation the framing may be such that the spring rate may be adjustable, and stops or rings may be provided to limit the separation of the rollers. 
         [0043]    The embodiments described above are exemplary only, and do not describe every possible aspect and application of the invention, as many of the mechanisms may be implemented in a variety of ways. The scope of the invention is limited only by the claims that follow.