Abstract:
A rope-climbing device has an upper assembly with planar side plates spaced apart by a roller, such that the side plates rotate relative to one another about a roller axis, a spine unit comprising planar links of common width each of half the plate spacing, the links pivoted at a central point, and a lower assembly comprising third and fourth side plates spaced apart by a clamp element such that the third and fourth side plates are enabled to rotate relative to one another about the clamp axis, and the clamp element is enabled to clamp a rope between the plates. The device may be opened by aligning pivot points, a rope inserted, and closed on the rope. Engaged on the rope, the device may be set to slide on the rope, or clamp to the rope by action of a user.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 14/805,366, filed Jul. 21, 2015, which will issue as U.S. Pat. No. 9,604,079 on Mar. 28, 2017, the disclosure of which is hereby incorporated herein in its entirety by this reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention pertains to a rope ascending/descending apparatus. The use of such apparatus relates to, but is not limited to: rope access, rock climbing, rescue work, and more specifically to work positioning as pertains to rope-assisted tree work. 
       BACKGROUND 
       [0003]    In many jobs and activities it is highly desirable to provide a safe, secure, and easy to use way to both climb and descend a rope. This includes tree work, rock climbing, rescue work, and tower or building repair or maintenance. The nature of tree work in particular also requires that such systems/devices/apparatus allow for movement of a climber both vertically and horizontally within a tree. Traditional systems rely on friction hitches or prusik knots applied to a doubled length of rope which runs over a limb or other anchor point in a dynamic 2:1 fashion. This is referred to as doubled dynamic rope technique (DdRT). More modern systems utilize a single length of rope affixed at one end to a limb or other anchor point in a static 1:1 fashion. This is referred to as single rope technique (SRT). The climber utilizes a device or apparatus that allows movement and positioning along the non-anchored leg of the rope. Due to the 1:1 nature of SRT, traditional friction hitches and prussic knots do not function satisfactorily. This necessitates the use of a mechanical element or device. 
         [0004]    Since the introduction of SRT to the field of tree work, there is a need for a single device, which can not only be used to both ascend and descend in a safe manner, but also to do so in a simple, easy manner, using only one hand to tend the ascender/descender mechanism. In addition, there is a need to provide a device of this type that is durable, automatically clamps when weight is applied, easily and quickly attaches to, and detaches from the rope, is easily adjusted for a range of rope sizes and constructions, does not require the use of removable pins or parts, and is compact in size and comfortable in the hand. It is further desirable to be able to use a single device employing either SRT or DdRT without modification. 
       BRIEF SUMMARY 
       [0005]    In one embodiment of the invention a rope-climbing device is provided, comprising:
       an upper assembly comprising first and second parallel planar side plates each having a common shape with a first free end and a second pivotal end, the first and second side plates spaced apart a first dimension by a roller at a point between the first and second ends by a roller axis through both first and second side plates, such that the side plates are enabled to rotate relative to one another about the roller axis, and the roller is enabled to rotate on the roller axis, the first side plate having a first fixed pin extending beyond the first dimension at a point between the free end and the roller axis, and the second side plate has a slot extending from one edge a distance into the second side plate, such that, with the side plates in rotated position with first free ends and pivot ends matching, the pin is fully engaged in the slot, a spine unit comprising first and second elongated planar links of common length and shape, and a common width each of half the plate spacing, the links pivoted to one another at a central point, with one end of the first link joined pivotally to the pivot end of the first side plate of the upper assembly, and one end of the second link joined pivotally to the pivot end of the second side plate of the upper assembly, and   a lower assembly comprising third and fourth parallel planar side plates each having a common shape with a first free end and a second pivotal end, the third and fourth side plates spaced apart at the first dimension by a clamp element at a point between the first and second ends by a clamp axis through both third and fourth side plates, such that the third and fourth side plates are enabled to rotate relative to one another about the clamp axis, and the clamp element is enabled to rotate on the clamp axis, the clamp element having an operating end configured to couple to a user&#39;s body harness, and a clamp end, the third side plate having a second fixed pin extending beyond the spacing of the third and fourth side plates at a point between the free end and the clamp axis, and the third side plate having a slot extending from one edge a distance into the second side plate, such that, with the side plates in rotated position with free ends and pivotal ends matching, the pin is fully engaged in the slot. The pivot points of the device, aligned in just one specific pattern, allow the first and second side plates of the upper assembly, the links of the spine assembly, and the third and fourth side plates of the lower assembly to rotate in concert, opening the device to allow a rope to be engaged between the first fixed pin and the roller of the upper assembly, and between the clamp element and the second fixed pin of the lower assembly, and wherein, with the rope engaged, the elements of the device are enabled to rotate in concert to close the device around the rope, and a user is enabled to rotate the elements with the device closed to slide freely on the rope or to clamp to the rope with weight applied to the operating end of the clamp element.       
 
         [0008]    In one embodiment of the invention the operating end of the clamp element comprises a ring of a size to engage a carabineer. Also in one embodiment, the first fixed pin comprises a first body eccentric to the pin axis, such that the first eccentric body may be rotated and fixed in different positions to adjust a distance between the roller and the eccentric body of the pin, thus accommodating ropes of different diameter. Also in one embodiment, the body and the fixed pin comprise a splined extension configured to engage a splined opening in the first side plate, such that the eccentric body may be inserted at different points and fastened to strongly resist rotation of the eccentric body in use. In one embodiment, the second fixed pin comprises a second body eccentric to the pin axis, such that the body may be rotated and fixed in different positions to adjust a distance between the clamp element and the eccentric body of the pin, thus accommodating ropes of different diameter. And in one embodiment, the device further comprises a third eccentric body of a diameter significantly larger than that of the second eccentric body, joined adjustably to the third side plate, engaging the second eccentric body in a manner that rotation of the second eccentric body adjusts the position of the third eccentric body relative to the clamp end of the clamp element, providing additional compensation for accommodating ropes of different diameters. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is an isometric view of an on-rope work positioning device according to one embodiment of the present invention, shown in neutral working position installed on rope. 
           [0010]      FIG. 2  is an isometric view of the positioning device of  FIG. 1  shown in open position for installation of rope. 
           [0011]      FIG. 3  is a side view of the positioning device of  FIG. 1  shown in open position with rope installed preparatory for use. 
           [0012]      FIG. 4  is a side view of the positioning device of  FIG. 1  shown in weighted position on rope (with upper and lower side plates not shown for clarity). 
           [0013]      FIG. 5  is an exploded view of the eccentric pin and bollard assembly of the positioning device of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0014]      FIG. 1  illustrates an on-rope work positioning device  100  for ascending and descending on a rope, in neutral or collapsed position on a rope  115 . Device  100  comprises an upper assembly  111 , a spine assembly  112 , a lower assembly  113 , and a pin/bollard assembly  114 . 
         [0015]    Upper assembly  111  comprises two generally parallel side plates  101  and  102 . These side plates are elongate in shape, generally flat in cross section, are constructed of a rigid material appropriate for high wear and stress applications and comprise each a first, second, and third aperture arranged sequentially along the length, patterned such that the apertures of side plate  101  and  102  match. Both side plates  101  and  102  comprise a pivot end and a control end. The distal aperture of the control end of side plate  101  is formed as a slot sized to mate an end portion of eccentric pin  108   a,  which is bolt  119   a,  and is formed such that bolt  119   a  may pass out of the slot by means of rotation of either side plate  101  or  102  relative to the other side plate. Bolt  119   a  additionally constrains eccentric pin  108   a  laterally within the slot when in closed position, spacing the side plates  101  and  102 . The distal aperture of the control end of side plate  102  is formed as (but not limited to) a round hole in some embodiments, and as a lobed star-shaped hole in some other embodiments, patterned to mate a matching pattern in an extended portion of eccentric pin  108   a,  (see  FIG. 5 ). Roller element  107  is affixed between side plates  101  and  102  by bolt  118   a  through the center aperture of side plates  101  and  102 , providing a pivot axis for roller  107 , such that a rope  115  may pass within the aperture formed by the side plates  101  and  102 , the roller  107  and eccentric pin  108   a.  The pivot end aperture of side plate  102  is joined pivotally to the upper aperture of link  106  by bolt  116   c  ( FIG. 2 ). The pivot end of side plate  101  is similarly joined pivotally to the upper aperture of link  105  by bolt  116   a  (see  FIG. 2 ). 
         [0016]    Lower assembly  113  comprises two generally parallel side plates  103  and  104 . These side plates are elongate in shape, generally flat in cross section, and are constructed of a rigid material appropriate for high wear and stress applications, just as are the side plates  101  and  102  of the upper assembly  111 . Lower side plate  103  comprises a first, second, and third aperture arranged sequentially along the length. Lower side plate  104  comprises a first, second, third and fourth aperture arranged sequentially along the length (see  FIG. 5 ) patterned such that the first, second, and third apertures of side plate  103  and  104  align. Both side plates  103  and  104  comprise a pivot end and a pin/bollard end. The distal (third) aperture at the pin/bollard end of side plate  103  is formed as a slot sized to mate the end portion of eccentric pin  108   b,  which is bolt  119   b,  and is formed such that bolt  119   b  may pass out of the slot by means of relative rotation between side plates  103  and  104 . Bolt  119   b  additionally constrains eccentric pin  108   b  laterally within the slot when in closed position. A fourth aperture of the pin/bollard end of side plate  104  is formed as (but not limited to) a slot which has a long axis generally parallel to the long axis of lower side plate  104  (see  FIG. 5 ). The third aperture of the pin/bollard end of lower side plate  104  comprises, but is not limited to, a round hole in some embodiments, or a lobed star-shaped hole patterned to mate a matching pattern milled or cast in an end portion of eccentric pin  108   b,  (see  FIG. 5 ). Cam/anchor element  110  is pivotally joined between side plates  103  and  104  by bolt  118   b  through the center aperture of side plates  103  and  104 , such that it may rotate freely about the major axis of bolt  118   b,  and such that a rope  115  passing through the upper assembly  111  may then pass within the aperture formed by side plates  103  and  104 , the cam/anchor  110  and eccentric pin  108   b  without interference. 
         [0017]    Cam/anchor  110  comprises a first and second aperture and a concave cam/friction face. The first aperture of cam/anchor  110  is sized such that a standard climbing carabineer may easily pass through the first aperture for the purpose of attaching a climber to the device  100 . The second aperture of cam/anchor  110  mates pivotally to the second aperture of lower side plates  103  and  104  by means of bolt  118   b  and functions as a pivot fulcrum for the cam action of cam/anchor  110 . 
         [0018]    Pin/bollard assembly  114  serves as an adjustable counter face upon which cam/anchor  110  compresses rope  115  (see  FIG. 4 ) and comprises eccentric pin  108   b , bollard  109 , and bolts  119   b,    119   d  and  501  (see  FIG. 5 ). Eccentric pins  108   a  and  108   b  are identical and are constructed of a hard-wearing material such as steel and have a central portion with a width that matches that of the space between upper side plates  101  and  102  and lower side plates  103  and  104 . At each end of the central portion there are extensions, both of which are centered about a common long axis, which is in turn parallel to and offset from the long axis of the central portion of the pin. Thus, when eccentric pins  108   a  and  108   b  are rotated about the long axis (rotational axis) of the smaller end extensions, the central portion rotates about the long axis in an eccentric fashion. Eccentric pins  108   a  and  108   b  are drilled and tapped through the rotational axis to receive bolts  119   a - 119   c.  Further, one end of each of eccentric pins  108   a  and  108   b  may be milled and/or shaped to a pattern matching that cut/milled into the third aperture of upper side plate  102  and lower side plate  104 , thus providing a mechanism for indexing the position of rotation of the eccentric pin (see  FIG. 5 ). In this manner, overall size of the rope aperture may be adjusted to accommodate various rope sizes and constructions. 
         [0019]    Bollard  109  is constructed of a wear-resistant and lightweight material such as aluminum and comprises a circular barrel of the same width as the central barrel of eccentric pin  108   a  and  108   b.  Bollard  109  comprises a first and second aperture. The first aperture of bollard  109  is offset from center and parallel to the centerline such that the first aperture overlaps an edge of the barrel forming thereby a semicircular cutout (see  FIGS. 2-5 ). The diameter of the semicircular cutout is the same as the diameter of the central portion of eccentric pin  108   b.  The second aperture comprises a tapped hole offset from and parallel to the center axis of bollard  109 , and mates to the slot (fourth aperture) of lower side plate  104  by means of bolt  501  such that bolt  501  may move freely within the slot and bolt  501  further constrains an outer face of bollard  109  to be flush with an inner face of lower side plate  104  (see  FIG. 5 ). The central portion of eccentric pin  108   b  fits within the first aperture of bollard  109  and rotates freely therein. As eccentric pin  108   b  is rotated to different positions, the eccentric position of the center barrel consequently moves bollard  109  in a reciprocal fashion constrained by bolt  501  within the slot (fourth aperture) in lower side plate  104  (see  FIG. 5 ). 
         [0020]    Bolt  119   d  is loosened to make such adjustment, and tightened again to hold bollard  109  in a new position. 
         [0021]    Upper assembly  111  and lower assembly  113  are joined by means of spine assembly  112 . Spine assembly  112  comprises link  105  and link  106 , which are mirror images of one another, each having an upper and a lower end. Both links  105  and  106  are elongate in shape, generally flat in cross section, are constructed of a rigid material appropriate for high wear and stress applications, and comprise each a first, second, and third aperture arranged sequentially along the length. Both links  105  and  106  are affixed to one another pivotally by bolt  117  through their centermost (second) apertures in such a way that they may freely rotate about the major axis of bolt  117 . The uppermost (first) aperture of links  105  and  106  are affixed to the pivot ends (first) apertures of upper side plates  101  and  102  respectively by bolts  116   a  and  116   c  (see  FIG. 2 ). Bolts  116   a - 116   c  are identical and comprise a flat head countersunk into link  105  such that link  105  may lay flush to, and move freely past link  106  without interference from the bolt head, and such that upper side plate  101  may additionally rotate about the major axis of bolt  116   a.  Bolt  116   c  (see  FIG. 2 ), link  106 , and upper side plate  102  mirror the arrangement of bolt  116   a,  link  105  and upper side plate  101 . The lower (third) aperture of link  105  and  106  mate with the first aperture of the pivot end of lower side plates  103  and  104  respectively in the same fashion as the upper (first) aperture of link  105  and  106  mate the pivot end (first) apertures of upper side plates  101  and  102 . 
         [0022]    As shown in neutral position in  FIG. 1 , device  100  moves freely along the length of rope  115  until the climber&#39;s weight is applied to the cam/anchor element  110 , which moves the friction face of element  110  to compress the rope between the friction face and bollard  109 , at which time the device  100  becomes configured in the locked position, as seen in  FIG. 4 . 
         [0023]      FIG. 4  shows the device  100  in locked or stationary position with upper side plate  101  and lower side plate  103  removed for clarity. In this position, the device  100  holds the climber&#39;s weight and remains stationary on the rope  115  until such time as the device is unlocked by application of downward force upon upper assembly  111 , to return the device  100  to the freely-sliding position shown in  FIG. 1 . When a climber&#39;s weight is applied, the force is transmitted from the cam/anchor  110  through the lower side plates  103  and  104 , through links  105  and  106 , to upper side plates  101  and  102  where friction between rope  115  and eccentric pin  108   a  cause side plates  101  and  102  to rotate roughly about the major axis of bolt  118   a.  This in turn causes the rope  115  to bend in a roughly “S” shaped curve about roller  107  and eccentric pin  108   a  thus increasing the friction generated at eccentric pin  108   a  and imparting a dragging force on the upper assembly  111 . This force is transmitted down the spine assembly  112  to the connected ends of the lower side plates  103  and  104 , which causes side plates  103  and  104  to pivot about the major axis of bolt  118   b  forcing the pin/bollard assembly  114  downwards and pushing the rope  115  into the face of cam/anchor  110 . It is the combination of friction forces acting in concert at the upper and lower assemblies, which allow the climber&#39;s position to be held on the rope. 
         [0024]      FIG. 5  shows an exploded view of pin/bollard assembly  114  and the mating of eccentric pin  108   a  to upper side plate  102  to illustrate an indexing function of these elements. The pattern manufactured into the end portion of eccentric pin  108   a  mates to the pattern manufactured in the third aperture of the upper side plate  102  for the purpose of indexing the rotational position of eccentric pin  108   a.  By withdrawing bolt  119   c  from eccentric pin  108   a , eccentric pin  108   a  can be pulled out of its mating aperture and rotated to a new position. It is then reinserted and bolt  119   c  is tightened to hold eccentric pin  108   a  in place during use. Eccentric pin  108   b  mates with the third aperture of lower side plate  104  in the same fashion as above with the addition of bollard  109 . Bollard  109  comprises a first and a second aperture. The first aperture of bollard  109  is offset from center and parallel to the centerline such that the first aperture overlaps the edge of the barrel forming thereby a semicircular cutout, the diameter of which is the same as the diameter of the central barrel of eccentric pin  108   b.  The second aperture comprises a tapped hole offset from and parallel to the center axis of bollard  109  and mates to the slot (fourth aperture) of lower side plate  104  by means of bolt  501  such that bolt  501  may move freely within the slot and bolt  501  further constrains the outer face of bollard  109  to be flush with the inner face of lower side plate  104 . The central barrel of eccentric pin  108   b  fits within the first aperture of bollard  109  and rotates freely therein. As eccentric pin  108   b  is rotated to different positions, the eccentric position of the center barrel consequently moves bollard  109  in a reciprocal fashion constrained by bolt  501  within the slot (fourth aperture) in lower side plate  104 . 
         [0025]      FIG. 2  shows the device  100  in open position preparatory to engaging the device  100  to or disengaging the device from a rope. To open the device  100  from neutral position, the upper assembly  111 , spine assembly  112 , and lower assembly  113  must be aligned in such a way that bolts  118   a,    116   a,    117 ,  116   b  and  118   b  align in a straight line one to the other. Upper side plates  101  and  102  may then rotate in opposing directions about the major axis of bolt  118   a,  links  105  and  106  may rotate in opposing directions about the major axis of bolt  117 , and lower side plates  103  and  104  may rotate in opposing directions about the major axis of bolt  118   b.  This results in a scissors-like action, which moves upper side plate  101  and lower side plate  103  away from eccentric pins  108   a  and  108   b,  respectively, and allows the rope to be inserted between the roller  107  and the eccentric pin  108   a  of the upper assembly  111  and the cam/anchor  110  and pin/bollard assembly  114  of the lower assembly  113 . If any of the five pivot points is not in the straight line with the other four, then the device cannot open. 
         [0026]      FIG. 3  shows the device  100  in the open position with the rope path  115  illustrated, upper side plate  101  removed for clarity. The rope  115  is passed between eccentric pin  108   a  and roller  107  as shown, then down and between eccentric pin  108   b  and the concave friction face of cam/anchor element  110 . The device  100  may then be closed, and weight may be applied to cam/anchor element  110 , which will cause the device to seize the rope  115  and bear the weight. 
         [0027]    The skilled person will understand that the descriptions made above are exemplary, and that there is a considerable range of variability in dimensions, material, fasteners, pivots and the like that may be made within the scope of the invention. Consequently, the scope of the invention is limited only by the claims that follow.