Patent Publication Number: US-7708246-B1

Title: Reticulated cam actuator

Description:
RELATED APPLICATIONS 
   This application claims the benefit under 35 U.S.C. 119(e) of the filing date of Provisional Application Ser. No. 60/608,487, filed Sep. 9, 2004, for “RETICULATED ACTUATOR”, the disclosure of which is hereby incorporated by reference as though set forth herein in its entirety. 

   BACKGROUND 
   1. Field of the Invention 
   This invention relates to equipment used in the sport of rock climbing. It is particularly directed to spring loaded camming devices used in such rock climbing, and provides an enhanced cam actuating mechanism. 
   2. State of the Art 
   Spring loaded camming devices (SLCDs), or commonly “cams”, are advantageously used in the sport of rock free-climbing as a source of leader protection for cracks having substantially parallel sides. In a typical climbing scenario, SLCDs are temporarily placed by a leading climber into cracks as protection, and clipped to a rope attached to the leading climber, as the leading climber advances up a rock face. A following climber generally “cleans”, or removes such protection from the crack. 
   At times, SLCDs placed into cracks may “walk” under the action of friction from the rope as a climber is climbing. In such circumstance, the camming device may move deeper into the crack from the initial placement location. It is not uncommon for a SLCD to walk, from an original placement location, deeper into a crack until its trigger is contained inside the crack. 
   It is possible for a walking SLCD to work its way (or even to be placed by the leading climber), sufficiently deep inside a crack that a following climber may be unable to retrieve it with his/her hand. Two situations commonly arise which create cam retrieval difficulty: either the cleaning climber&#39;s hand/fingers cannot engage the trigger due to crack constriction, or the camming device is too deep for the climber to reach. Sometimes, the crack is simply too narrow to admit passage of the follower&#39;s fingers to a sufficient depth. In a crack that is slightly less narrow, the follower&#39;s fingers still may not have sufficient room to pass between the trigger of the SLCD and a wall of the crack. If the climber&#39;s fingers cannot get a purchase on the SLCD&#39;s trigger, the SLCD can be very difficult to remove from the crack. 
   A dedicated cam actuating and retrieving device has been commercially available under the name “Friend of a friend”, and is indicated generally at  100  in  FIG. 1 . This device  100  has an actuator arranged somewhat similar to a syringe, and has a fixed length of perhaps about 8-10 inches in its stowed (compact) position. The “fingers”  102  are formed from the tubular metal body  104 , and are therefore fixed in position to cooperate with the “thumb”  106 . Such fixed fingers  102  cannot be placed into retracting engagement on a trigger of an SLCD that is in a narrow crack (e.g. a crack that is about ⅜ to ⅝ inches in width, or so), because the fingers  102  have a fixed height “H”, which cannot be inserted into the crack to pass between the SLCD&#39;s trigger and a wall of the crack. 
   Nut cleaning tools are also sometimes used as an aid to retrieve cams which are unreachable by hand. A representative nut cleaning tool is indicated generally at  110  in  FIG. 2 . Such nut cleaning tools  110  may be formed from steel sheet metal of about 10 gage, or so. Nut cleaning tools generally have a hook  112  which may be used to snag a SLCD&#39;s trigger. However, it can be difficult to coordinate pulling on the nut tool while simultaneously pushing on the stem of the SLCD to cause the individual cam lobes to rotate. Furthermore, the hook  112  typically engages the trigger of the stuck SLCD effective only to actuate a single cam element, or perhaps a pair of cam elements. Therefore, the remaining (and unretracted), cam elements of the SLCD can resist removal of the SLCD from the crack. 
   A need exists for a tool to assist in retrieving cams which become wedged too deep in a crack for a climber to remove either by hand or with the assistance of a commercially available device. It would be an advance to provide a cam actuating tool capable of actuating a cam in even a very narrow crack. It would be a further advancement if such tool provided the ability to place and remove a cam at an extended distance compared with available devices. 
   BRIEF SUMMARY OF THE INVENTION 
   Embodiments of the invention may be regarded as being reticulated, in that one or more translatable and rotatable remote fingers operates in harmony as a network or system with a remote thumb to apply a compressive force to an object disposed between the finger and thumb. Preferred embodiments of the invention are operable to obtain a grip on structure that is located in a narrow confine, such as in a crack, hole, or crevice. In use of the invention, a remote finger can be rotated out-of-plane, extended to bypass an object, then rotated back into-plane and retracted to urge the object toward a remote thumb. The object can then be gripped and manipulated, e.g. removed from a crevice. Rotation of the remote finger can enable the remote finger to pass between the object and a wall of a narrow confine by orienting the remote finger to fit in the available bypass space between the object and wall. 
   The present invention provides an apparatus particularly adapted for actuating spring-loaded camming devices (SLCDs) used in the sport of rock climbing. Embodiments of reticulated actuators structured according to the invention are operable to actuate and extract deeply located SLCDs in many cases. Actuating an SLCD involves retracting its trigger to cause individual cam lobes of the SLCD to rotate, and thereby present a reduced size for placement and/or extraction of the SLCD with respect to a crack. Preferred embodiments constructed according to principles of the invention are adapted to assist in retracting the trigger of a SLCD. Of course, a reticulated actuator structured according to certain principle of the instant invention may be used in other applications that benefit from rotating a remote finger out-of-plane and extending the remote finger to bypass structure to be gripped between the restored in-plane finger and a remote thumb. 
   One embodiment of the invention includes a retraction mechanism and a control interface adapted to operate the retraction mechanism. An operable retraction mechanism includes a first remote finger arranged to cooperate with a remote thumb. The first remote finger is arranged to translate along a first axis to cause a variable spacing between the first remote finger and the remote thumb. The first remote finger is also adapted to permit its rotation about the first axis. Currently preferred embodiments of the invention also include a second remote finger disposed to translate along a second axis disposed substantially in parallel with the first axis such that a second variable spacing may be established between the second remote finger and remote thumb. The first and second variable spacings may be independently adjusted, or may be slaved together. Preferably, the second remote finger is also adapted to permit its rotation about the second axis. Rotation of the remote fingers may be independent, or may be slaved together. 
   An operable control interface is adapted to receive input from a human hand effective to cause the variable spacing between a remote finger and remote thumb. One operable control interface includes a trigger connected by a linkage to a remote finger. Movement of such trigger causes a corresponding motion of the remote finger. Certain operable triggers can be rotated through an angle of about 90 degrees. Currently preferred triggers can be rotated through an angle of about 180 degrees. A representative control interface used in a reticulated actuator for extracting SLCDs typically can cause up to about 4 inches to 6 inches of translation of the remote finger(s). 
   It is currently preferred for a remote finger to have a length and a width orthogonal to its length, with the width being smaller in size than the length. Therefore, the remote finger can be rotated about its translation axis such that the remote finger presents a reduced size to enhance its passage between the item and a wall of a crevice. Once the remote finger has been inserted deeper inside the crevice than the item to retrieve, the remote finger can be rotated and retracted effective to capture the item between the remote finger and remote thumb. 
   Certain embodiments of the invention may be characterized as including a handle having first and second ends spaced apart along a length axis, with pushing structure being associated with the first end. The handle also desirably includes an arm keeper and a remote thumb associated with the second end. A first retractor arm can be disposed in harmony with the arm keeper operably to permit displacement of the first retractor arm in a direction along a first slide axis disposed substantially parallel to the handle&#39;s length axis, and to permit rotation of the first retractor arm about the first slide axis. A first trigger is operably associated with a first end of the first retractor arm and a first remote finger is associated with a second end of the first retractor arm effective to couple motion of the first trigger to motion of the first remote finger. The assembly is configured and arranged to permit manipulation of the first trigger and pushing structure by way of human hand input operably to rotate and displace the first remote finger relative to the remote thumb. 
   Preferably, the arm keeper is adapted to resist rotation of the first retractor arm about first and second orthogonal Cartesian axes, and to permit rotation of the first retractor arm about a third Cartesian axis disposed orthogonal to the first and second Cartesian axes and substantially in parallel with the handle&#39;s length direction. Also it is desirable for the arm keeper to resist displacement of the first retractor arm along the first and second Cartesian axes, and to permit displacement of the first retractor arm along the third Cartesian axis. 
   Certain embodiments structured according to principles of the invention include a second retractor arm disposed in harmony with the arm keeper operably to permit displacement of the second retractor arm in a direction along a second slide axis disposed substantially parallel to the handle&#39;s length axis, and to permit rotation of the second retractor arm about the second slide axis. A second trigger is operably associated with a first end of the second retractor arm and a second remote finger is associated with a second end of the second retractor arm effective to couple motion of the second trigger to motion of the second remote finger. Such devices are typically configured and arranged to permit manipulation of the second trigger and pushing structure by way of human hand input operably to rotate and displace the second remote finger relative to the remote thumb. 
   Certain embodiments of the invention may be configured to fold, or otherwise be reduced in length, for transport. Desirably, devices structured according to principles of the instant invention and used in the sport of rock climbing have an overall stowed length of less than about 20 inches. Such devices may have a deployed length of about twice their stowed length, or more. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings, which illustrate what are currently considered to be the best modes for carrying out the invention: 
       FIG. 1  is view in perspective of a prior art cam-actuating device; 
       FIG. 2  is a plan view of a prior art nut tool that can be used in a pinch to actuate the trigger of an SLCD; 
       FIG. 3  is an exploded assembly view in perspective of a currently preferred embodiment of the invention; 
       FIG. 4  is a side view in elevation of a second embodiment according to the invention; 
       FIG. 5  is a bottom view of the embodiment illustrated in  FIG. 4 ; 
       FIG. 6  is an end view of the embodiment of  FIG. 5 , taken from section  6 - 6  and looking in the direction of the arrows; 
       FIGS. 7-10  illustrate extrusion profiles for components of the embodiment illustrated in  FIGS. 4 and 5 ; 
       FIG. 11  is a side view of a third embodiment constructed according to prociples of the instant invention; 
       FIG. 12  is a section view taken through section  12 - 12  in  FIG. 11 , and looking in the direction of the arrows; 
       FIG. 13  is an alternative arrangement for structure illustrated in  FIG. 12 ; 
       FIG. 14  is a section view taken through section  14 - 14  in  FIG. 11 , and looking in the direction of the arrows; 
       FIG. 15  is a section view through a lanyard attach point; and 
       FIG. 16  illustrates a representative commercially available SLCD of the type having a center-pull arrangement. 
   

   DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
   Reference will now be made to the drawings in which the various elements of the illustrated embodiments will be given numerical designations and in which the invention will be discussed so as to enable one skilled in the art to make and use the invention. It is to be understood that the following description is only exemplary of the principles of the present invention, and should not be viewed as narrowing the claims which follow. 
   As illustrated in  FIG. 3 , a currently preferred embodiment of the invention, generally indicated at  200 , includes a handle  202 , a pair of retractor arms  204 ,  205 , and arm keeper structure generally indicated at  207 . A handle  202  can be formed from any material, such as wood, metal, etc., that is sufficiently stiff to resist a compressive load generated in operation of the device  200 . Such compressive load is transferred between a proximal end of the handle  202  and a remote thumb disposed at a distal end of handle  202 , and generally indicated at  208 . A workable thumb provides a surface against which a stem of a SLCD can be pressed. Sometimes, thumb  208  may include socket structure, or a textured surface, or other structure arranged to resist slipping of the SLCD&#39;s stem as the SLCD is actuated. 
   Embodiments of the invention typically include an arm keeper  207  effective to help guide a retractor arm for convenient manipulation of its remote finger. Illustrated arm keeper  207  includes a pair of axially elongated sockets  209  in which arms  204  and  205  are captured by plate  212 . An installed retractor arm  204  is free to translate along, and rotate about, axis  213 . Similarly, an installed retractor arm  205  is free to rotate about, and translate along, axis  214 . Axis  213  is disposed substantially parallel to axis  214 , and these axes are spaced apart by a distance indicated at “W”. Desirably, axes  213  and  214  are also disposed substantially in parallel with a length axis of handle  202 . 
   Plate  212  may be affixed to handle  202  by way of one or more fasteners  218 , or by way of any other appropriate and well known construction technique. It is currently preferred to install a pair of such fasteners  218  through countersunk holes  220  and holes  222  for robust redundancy and to resist rotation of plate  212  with respect to handle  202 . An operable plate  212  may be formed from a section of sheet metal, with stainless steel being currently preferred. However, other materials, including ferrous and nonferrous metals, plastics, and the like, can be used as well. In general, the plate  212  may be made from any material having sufficient structural properties to maintain the retractor arms  204 ,  205  in an alignment with respect to the handle  202 . Desirably, the thumb  208  (including its installed plate  212 ) has a total thickness “T” of less than about ¾ inches, or even less than about ½ inch, to permit inserting the assembled remote thumb into thin crevices. 
   A representative retractor arm, such as arm  204 , includes a trigger  226  disposed at a proximal end and a remote finger  228  disposed at a distal end. The trigger  226  forms a space  230  structured to receive a user&#39;s finger for manipulation of the remote finger  228 . The remote finger  228  is structured to form a space  232  in which to capture the actuation trigger of a SLCD. As illustrated, trigger  226  of the preferred embodiment  200  is arranged to define finger space  230  oriented approximately in an x-y plane, where the x axis is oriented along the length direction of the handle  202 . The capture space  232  is desirably oriented approximately in an x-z plane, as illustrated. It is desirable to orient the finger space  230  and capture space  232  substantially orthogonal to each other to facilitate operation of the device  200 , and to provide a convenient and compact stowed configuration of the device  200 . Similarly, it is desirable for finger receiving space  234  of arm  205  to be disposed approximately in an x-y plane as illustrated, and for capture space  236  to be disposed approximately in an x-z plane. 
   Arms  204  and  205  are illustrated in an orientation representative of a deployed retraction position. In such position triggers  226 ,  226 ′ and pushing structure, generally indicated at  238 , may be operated similarly to a syringe. As illustrated, triggers  226 ,  226 ′ may be characterized as flaring away from the handle  202 . Operable pushing structure  238  provides a surface against which to engage a user&#39;s thumb or palm. In such deployed retraction position, triggers  226  and  226 ′ are oriented approximately in, or parallel to, the same plane to permit convenient retraction by selected ones of the user&#39;s fingers. Triggers  226  and  226 ′ can be individually retracted to separately control the spacing between each of fingers  228  and  228 ′ and remote thumb  208 . Rotation of triggers  226 ,  226 ′ can also be separately adjusted. However, it is within contemplation to configure arms  204  and  205  to slave either, or both, of translation and rotation of fingers  228 ,  228 ′ together. 
   It is convenient to provide structure arranged to hold arms  204 ,  205  in a stowed (compact) position. One workable arm retaining structure includes a string lanyard  239  arranged as a figure “8”, with one loop of the “8” passing through both of holes  240  and  242 . Arms  204 ,  205  can be rotated to place triggers  226 ,  226 ′ parallel to the sides of body  202 , and with trigger structure disposed between the holes  240 ,  242 . Each of the loops  244 ,  246  of string stretching between holes  240 ,  242  on each side of body  202  can then be entrained about a cooperating trigger, and snugged tight to capture the respective triggers against the body  202 . The free loop  248  of the lanyard can then be used to clip the device  200  to a climber&#39;s rack or harness using a carabiner. 
   Desirably, at the stowed position, remote fingers  228 ,  228 ′ are disposed in a stowage position effective to resist snagging the remote fingers on items during transport of the device  200 . One operable stowage configuration locates the fingers in a socket structure provided by remote thumb  209 . 
   Remote fingers  228 ,  228 ′ are configured to provide sufficient length indicated at “D” to capture the triggers of a range of commercially available SLCDs. A workable length is about ½ inch, or so. Desirably, the finger length “D” is sized in harmony with the spacing “W”, so that the fingers  228 ,  228 ′ can be rotated to point at each other in the stowed position, with the triggers being substantially flat against the sides of body  202 . Desirably, a spacing between adjacent retractor arms is determined in conformance with a spacing between structural members (or cam actuating cables), of a variety of SLCDs that are commercially available. Such spacing between arms positions an extended pair of remote fingers for rotating into contact with the structural members (or cam actuating cables), and helps to hold the SLCD securely in the device for manipulation of the SLCD inside the crevice. Such configuration also facilitates placing first one, and then the second remote finger, into proper holding position with respect to the trigger of the SLCD. A workable spacing “W” between arms  204 ,  205  is between about ½″ and 1½″, or larger. It has been determined that a spacing “W” of about 1 inch, or so, is adequate to permit the device  200  to interface with most, if not all, commercially available SLCDs. 
   A workable overall stowed length of a representative device  200  is about 10 to 12 inches, more or less. Desirably the stowed length is less than about 20 inches. It is within contemplation also to provide a reticulated retractor having a variable length that may be determined by a user in the field. Therefore, certain embodiments may include a hinged body and arms to permit folding the device for more convenient transport. 
   Arms  204 ,  205  are typically made from wire stock, such as from a steel rod of about ⅛ inch in diameter. Illustrated arms  204 ,  205  are simply bent to shape, although multipiece arms are within contemplation. Remote fingers  228 ,  228 ′ may also include hook-like tips, as illustrated, or pointy tips to assist in capturing the trigger of a SLCD. It is preferred to form arms  204 ,  205  from stainless steel material, to resist rust and corrosion. Arms  204 ,  205  can be made from other materials as well, so long as the material provides sufficient resistance to bending to permit actuation of stubborn SLCDs. 
   It is currently preferred to injection mold a handle  202  from a plastic or plastic-like material, such as Nylon, ABS, PVC, polyurethane, rubber, TEFLON™, and the like. Desirably, handle material is sufficiently tough to stand up to scraping, banging, and general knocking about against rocks, both during its use and when stowed on a climber&#39;s rack or harness. Handle  202  advantageously can include rib structure (not illustrated) configured to reduce its weight and amount of required constituent material. It is further within contemplation to form handle  202  in a straight-pull mold, including a first hinged section at the lanyard end and a second hinged section (structured as an alternative to plate  212 ) at the arm keeper end. Such hinged sections may be “folded”, with each folded section being secured to the bulk of handle  202  by way of one or more fasteners. The first mentioned folding section can be structured to define the lanyard holes and (optionally, if desired) simultaneously capture (to install) a lanyard. The second folding section can be structured to capture arms in sockets  209 . Of course, the respective sections do not have to be hinged from the bulk of the handle, but such construction may enhance simplicity of assembly. 
     FIGS. 4-10  illustrate details of an alternative embodiment constructed according to principles of the instant invention, and generally indicated at  300 .  FIGS. 3-10  are scale drawings of a workable embodiment. Portions of retractor device  300  are structured to be assembled from sections cut from extruded stock, such as Aluminum. Illustrated device  300  includes a handle  302 , an arm keeper  304 , an end cap  306 , and a hook  308 . Operable extrusion profile shapes for the hook  308 , end cap  306 , arm keeper  304 , and body  302  are illustrated in  FIGS. 7-10 , respectively. The components can be structured to have cooperating thicknesses to permit assembly using the same size rivet  310 . 
   In  FIGS. 4 and 5 , triggers  312  of the retractor arms  314  are illustrated using dashed lines to indicate a stowed position, and solid lines to indicate a deployed position. In  FIG. 4 , the dashed indicator line points out a fully retracted position for remote finger  316 , and the solid indicator line points out an extended position for finger  316 . In  FIG. 5 , the remote fingers  316  are illustrated with dashed lines in a stowed position, and solid lines at an extended, deployed position. It is desirable to provide a socket  318  in which to stow remote fingers  316 , and in which to hold a stem of a SLCD. A pair of lanyard holes  320  passing through rails of illustrated handle body  302  permit installation of a lanyard (not illustrated) operable to trap triggers  312  in a stowed position, and to suspend device  300  from a climber&#39;s rack or harness. 
   A third embodiment constructed according to certain principles of the instant invention is illustrated in  FIG. 11 , and generally indicated at  340 . Device  340  includes a retraction mechanism, generally indicated at  342 , and a control interface, generally indicated at  344 . The retraction mechanism includes a remote finger  346  arranged to cooperate with remote thumb  348 . Control interface  344  includes pushing structure, generally indicated at  350 , and trigger  352 . A single retractor arm  354  connects trigger  352  and remote finger  346  so that manipulation of trigger  352  causes a corresponding movement of remote finger  346 . Device  340  is particularly adapted to extract SLCDs of the type providing a center-pull arrangement, such as illustrated in  FIG. 16 . However, device  300  may also be used to extract other SLCDs having triggers adapted for convention two-finger gripping. 
   Arm  354  is disposed for reticulation along an axis inside bore  356  that extends through arm keeper  358 . An operable arm  354  may be constructed in similar fashion to arms  204 ,  205 , and from similar materials. Such arm may include the remote finger  346 ′ structured as illustrated in  FIG. 13 . Alternatively, a remote finger  346  may be swaged, soldered, or welded to a distal end of arm  354 . In the latter case, the remote finger can be structured to have a width W 1  that is larger than a diameter of the arm  354 . A width W 1  may provide enhanced control of trigger retraction for a SLCD. In any case, it is preferred for the width W 1  to be smaller than the width W 2 , to permit rotation of the remote finger  346  (or  346 ′) to an orientation presenting a smaller profile to fit between the trigger of a stuck SLCD and a wall of the crack in which the SLCD is stuck. 
   Desirably a lanyard hole  360  is formed in the proximal end of the handle  361 . Therefore, a lanyard  362  may be threaded through hole  360  to trap trigger  352  of retractor arm  354  in a stowed position (see  FIG. 15 ). 
   The devices illustrated in FIGS.  3  and  4 - 5  have mirror image left and right retractor arms that each can be rotated by about 180 degrees around their respective slide axes to permit moving their associated remote fingers from a storage position, past a trigger retraction position at about 90 degrees, and then through about 90 additional degrees to a bypass position. At the bypass position, the remote fingers are oriented approximately parallel to a wall of an assumed crack, and more favorably positioned for placement in a depth direction into the crack to bypass, and get behind, the SLCD&#39;s trigger. Once positioned behind the trigger of the SLCD, the remote fingers are then counter-rotated by about 90 degrees to a retraction position to interface with the SLCD&#39;s trigger. 
   Also, in the bypass position, the device&#39;s triggers are pointed in a helpful direction; protruding away from a possible dihedral wall or offset wall of the crack system. Therefore, the triggers are positioned for better access to, and manipulation by, the cleaner. At an SLCD trigger retraction position, the device&#39;s triggers are spaced apart from a dihedral or offset wall by at least about the thickness of the device&#39;s body, so a cleaner can place his/her fingertips into the trigger loops and operate the device as a hypodermic-like retractor. 
   It is within contemplation to form reticulated retraction devices having identical left and right triggers. Such triggers can be arranged to rotate by only about 90 degrees from a stowed position (same orientation as retraction position), to a bypass position. Such construction could reduce manufacturing complexity. An embodiment can be visualized by adding a second retractor arm in parallel and offset from the single retractor arm illustrated in  FIG. 11 . Therefore, the triggers would be actuatable in a position similar to the trigger of a gun. Unfortunately, such trigger positioning undesirably reduces the number of conformations of crack systems in which the device may be used. 
   It is also within contemplation for the device to be alternatively constructed to permit the device&#39;s triggers to be rotated to overlap across the center of the body at a storage or retraction position. A central opening may be disposed oriented along a length axis of the device to provide improved finger access to such triggers. Overlapped triggers could then be actuated together by a single finger. However, such configuration may reduce effectiveness of independent trigger actuation. Often, it is desirable to be able to retract each trigger of a two-retractor-arm device independently, effective to urge one or more cam element of an SLCD to move independently of other such elements. 
   While the invention has been described in particular with reference to certain illustrated embodiments, such is not intended to limit the scope of the invention. The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.