Abstract:
A connector system includes an insert configured to be attached to a first object and a magnetic coupler configured to be attached to a second object. The magnetic coupler has a quick connect receiver receiving the insert. The magnetic coupler has a magnet magnetically attracting the insert into the quick connect receiver. The magnetic coupler has insert latches engaging and locking the insert in the quick connect receiver. The insert latches are releasable to allow the insert to be removed from the quick connect receiver.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/772,763 filed Mar. 5, 2013 and titled MAGNETIC COUPLER, the subject matter of which is herein incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The subject matter herein relates generally to magnetic couplers. 
         [0003]    There are many instances where a tether has to be selectively attached or detached from a secondary object. For instance, boats have to be connected and disconnected from docks. Cargo straps have to be attached and detached to cargo on the bed of a truck. Leashes have to be attached and detached from collars of pets. 
         [0004]    The most popular connector used to attach a tether to a secondary object is a spring hook. A spring hook is a hooked structure having an open eye. A spring biased pawl obstructs the access into the eye. The spring biased pawl must be manipulated out of the way before the open eye of the hook structure can receive a loop. A problem associated with spring hook connectors is that they are difficult to attach and detach using only one hand. Such spring hooks are also particularly difficult to attach and detach if the secondary object is movable, such as when connected to a collar of a pet. 
         [0005]    In the prior art pet leashes, many designs have been created that attempt to improve the ease with which a person can attach a leash to a collar. Some of these prior art connectors utilize magnetic attraction. For instance, in U.S. Pat. No. 3,589,341 to Krebs, entitled Animal Collar With Magnetic Fastener, a coupling is shown that closes using magnetic attraction. Such a collar coupling is very easily closed. However, should an animal pull on the collar with any force greater than the forces of the attracting magnets, the connector will open. Thus, the collar is limited to small animals, such as cats and miniature dogs. 
         [0006]    U.S. Pat. No. 7,389,750 to Rogers, entitled Quick Connect Tether Connecting System, discloses a leash and collar system for a pet that uses magnetic coupling and locking elements. Additionally, U.S. Pat. No. 7,954,211 to De Bien, entitled Quick Connect Coupling Assembly describes a leash and collar system for a pet that uses magnetic coupling and locking elements. However, such assemblies are difficult to manipulate and actuate to couple and uncouple the components. 
         [0007]    A need remains for a magnetic coupler that is cost effective and reliable. A need remains for a magnetic coupler that is easy to use. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0008]    In one embodiment, a dog leash system is provided having an insert configured to be attached to a dog collar and a magnetic coupler configured to be attached to a leash. The magnetic coupler has a quick connect receiver receiving the insert. The magnetic coupler has a magnet magnetically attracting the insert into the quick connect receiver. The magnetic coupler has insert latches engaging and locking the insert in the quick connect receiver. The insert latches are releasable to allow the insert to be removed from the quick connect receiver. The magnetic coupler may be automatically locked when the insert is drawn into the magnetic coupler. 
         [0009]    In another embodiment, a magnetic coupler is provided having a housing having a receptacle at a mating end of the housing where the receptacle is configured to receive an insert therein. Insert latches are movably coupled to the housing and located at the receptacle. The insert latches are movable between a locking position and a clearance position. The insert latches are configured to engage and lock the insert in the receptacle in the locking position. The insert latches allow the insert to be removed from the receptacle in the clearance position. A sheath is slidably coupled to and surrounds the housing. The sheath is movable between a cocked position and a blocking position. In the cocked position, the insert latches are capable of moving to the clearance position and in the released position the sheath is configured to block the insert latches from moving to the clearance position. A magnet is held by the housing. The magnet is configured to magnetically attract the insert into the receptacle. A sheath latch is movably coupled to the housing. The sheath is movable between a latched position and an unlatched position. In the latched position, the latch engages the sheath and holds the sheath in the cocked position. An ejector is movably coupled to the housing. The ejector is actuated to eject the insert from the receptacle. The coupler may transition from the clearance position to the locking position when the insert is inserted into the receptacle activating the trigger housed in the housing. The trigger releases the sheath from the cocked position to the blocking position. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  illustrates a magnetic coupler system formed in accordance with an exemplary embodiment. 
           [0011]      FIG. 2  is a side perspective view of a magnetic coupler for the magnetic coupler system and formed in accordance with an exemplary embodiment. 
           [0012]      FIG. 3  is a side view of the magnetic coupler. 
           [0013]      FIG. 4  is another side view of the magnetic coupler. 
           [0014]      FIG. 5  is an exploded view of the magnetic coupler. 
           [0015]      FIG. 6  is a cross-sectional view of the magnetic coupler and an insert showing the magnetic coupler cocked and ready to receive the insert. 
           [0016]      FIG. 7  is a cross-sectional view of the magnetic coupler and insert showing the insert locked into the magnetic coupler. 
           [0017]      FIG. 8  is an exploded view of a magnetic coupler formed in accordance with an exemplary embodiment. 
           [0018]      FIG. 9  is an exploded view of a magnetic coupler formed in accordance with an exemplary embodiment. 
           [0019]      FIG. 10  is a cross-sectional view of the magnetic coupler shown in  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]      FIG. 1  illustrates a magnetic coupler system  100  formed in accordance with an exemplary embodiment. The magnet coupler system  100  includes a magnetic coupler  102  and an insert  104  configured to be coupled to the magnetic coupler  102 . The magnetic coupler  102  is coupled to a first object  106  and the insert  104  is coupled to the second object  108 . The magnetic coupler system  100  connects the first object  106  with the second object  108 . 
         [0021]    In an exemplary embodiment, the first object  106  may be a tether or leash. The second object  108  may be any type of object, including a pet collar. The magnetic coupler system  100  may be used as a dog leash system that is used to connect the leash to a collar. The magnetic coupler system  100  may be used in other applications in alternative embodiments such as industrial applications, marine applications, commercial applications, automotive applications, tooling applications, or in other fields to connect two objects together. The magnetic coupler system  100  may be connected to any type of object, including a strap, a hook, a wire, a rope or other types of objects. 
         [0022]    The magnetic coupler system  100  utilizes magnets to magnetically attract the insert  104  to the magnetic coupler  102 . The magnetic coupler  102  and/or the insert  104  may include one or more magnets therein. Optionally, the insert  104  may be quickly and easily coupled to and uncoupled from the magnetic coupler  102 . Once coupled, the insert  104  may be locked or retained in the magnetic coupler  102  until the insert  104  is manually released from the magnetic coupler  102 . Any type of know connecting means may be used to connect the first object  106  to the magnetic coupler  102  and to connect the second object  108  to the insert  104 . 
         [0023]      FIG. 2  is a side perspective view of the magnetic coupler  102  formed in accordance with an exemplary embodiment.  FIG. 3  is a side view of the magnetic coupler  102 .  FIG. 4  is another side view of the magnetic coupler  102 . The insert  104  is shown coupled to the magnetic coupler  102  in  FIGS. 2-4 . The magnetic coupler  102  includes a quick connect receiver  110  configured to receive the insert  104 . The quick connect receiver  110  defines a female section of the magnetic coupler system  100  and the insert  104  defines a male section of the magnetic coupler system  100 . 
         [0024]    The quick connect receiver  110  includes a housing  112  having a receptacle  114  (shown in  FIG. 6 ) at a mating end  116  of the housing  112 . The receptacle  114  is configured to receive a plug end of the insert  104  therein. A handle  118  is coupled to the housing  112  for connecting the magnetic coupler  102  to the first object  106  (shown in  FIG. 1 ). The handle  118  may be rotatably coupled to the housing  112 . Other securing means may be provided in alternative embodiments to secure the magnetic coupler  102  to the first object  106 . 
         [0025]    The magnetic coupler  102  includes an outer sheath  120  slidably coupled to and surrounding the housing  112 . The sheath  120  is movable between a cocked positioned and a blocking position. In the cocked position, quick connect features used to secure the insert  104  in the receptacle  114  are capable of being released to allow the insert  104  to be loaded into the receptacle  114  or removed from the receptacle  114 . In the blocking position, the outer sheath  120  blocks the quick connect features from moving, thus securing the insert  104  in the receptacle  114 . 
         [0026]    In an exemplary embodiment, the sheath  120  includes finger grips  122  that allow a user to grasp the sheath  120  to move the sheath  120  from the blocking position to the cocked position. In an exemplary embodiment, the sheath  120  includes slots  124  proximate to the location where the handle  118  connects to the housing  112 . The slots  124  allows the sheath  120  to move relative to the handle  118  and housing  112  between the cocked position and the blocking position. 
         [0027]    The magnetic coupler  102  includes an ejector  130  that is movably coupled to the housing  112 . The ejector  130  is actuated to eject the insert  104  from the receptacle  114 . In an exemplary embodiment, as described in further detail below, the ejector  130  is used to lock the sheath  120  in the cocked position. When the ejector  130  is released, the sheath  120  may be freed to move from the cocked position to the blocking position, as described and further detailed below. In the illustrated embodiment, the ejector  130  is coupled to the housing  112  at a rear  132  or back end of the housing  112  generally opposite the mating end  116  or front of the magnetic coupler  102 . 
         [0028]      FIG. 5  is an exploded view of the magnetic coupler  102  showing the housing  112 , sheath  120  and ejector  130 . The sheath  120  includes a chamber  140  extending between a front  142  and a rear  144 . The chamber  140  receives the housing  112 . The sheath  120  is movable relative to the housing  112  during operation of the magnetic coupler  102 . A shoulder  146  extends into the chamber  140  from an interior wall  148  defining the chamber  140 . The shoulder  146  may limit travel of the sheath  120  relative to the housing  112 . In an exemplary embodiment, the sheath  120  includes one or more pockets  150  in the interior wall  148  proximate to the rear  144 . 
         [0029]    The housing  112  extends between a front  160  and a rear  162 . The receptacle  114  (shown in  FIG. 6 ) is provided at the front  160  and is configured to receive the insert  104  (shown in  FIG. 6 ). In an exemplary embodiment, the housing  112  includes front openings  164  proximate to the front  160  and rear openings  166  proximate to the rear  162 . The front openings  164  are configured to receive insert latches  168  therein. The rear openings  166  are configured to receive sheath latches  170  that are used to lock the sheath  120  in a cocked position. 
         [0030]    The insert latches  168  define quick connect features of the magnetic coupler  102  that are used to retain the insert  104  in the receptacle  114 . The insert latches  168  are movable within the front openings  164  between a locking position and a clearance position. The insert latches  168  are configured to engage and lock the insert  104  in the receptacle  114  in the locking position. The insert latches  168  allow the insert  104  to be removed from the receptacle  114  in the clearance position. In an exemplary embodiment, the latches  168  are movable radially into and out of the receptacle  114  between the locking position and clearance position. In an exemplary embodiment, the insert latches  168  are ball bearings that are spherical in shape, where portions of the insert latches  168  are configured to be moved into the receptacle  114  in the locking position. Other types of insert latches may be used in alternative embodiments, such as spring loaded latches, rocker latches, or other type of latches. 
         [0031]    The sheath latches  170  are movably coupled to the housing  112 . For example, the sheath latches  170  may be rotatably coupled to the housing  112  in the rear openings  166 . The sheath latches  170  are movable between a latched position and an unlatched position. In the latched position, the sheath latches  170  are configured to engage the sheath  120  and hold the sheath  120  in the cocked position. In the unlatched position, the sheath latches  170  are moved out of the way to provide clearance to allow the sheath  120  to move from the cocked position to the blocking position. In the blocking position, the sheath  120  is configured to block the insert latches  168  from moving out of the locking positions to the clearance positions. The sheath  120  is thus used to lock the insert  104  in the magnetic coupler  102  by blocking the insert latches  168  from moving to the clearance positions. 
         [0032]    The housing  112  includes slots  172  along opposite sides thereof. The handle  118  is received in the slot  172 . The handle  118  may be secured to the housing  112  by other means in alternative embodiments. 
         [0033]    The housing  112  includes a grove  174  proximate to the front  160 . The grove  174  is configured to receive a retaining ring  176  used to retain the sheath  120  on the housing  112 . 
         [0034]    In an exemplary embodiment, the housing  112  includes an ejector chamber  178  at the rear  162 . The ejector chamber  178  receives the ejector  130 . The ejector  130  is movable within the ejector chamber  178 . In an exemplary embodiment, the housing  112  includes a groove  180  within the ejector chamber  178  that receives a retaining ring  182  used to retain the ejector  130  within the ejector chamber  178 . 
         [0035]    The housing  112  includes a flange  184  extending outward from an exterior surface of the housing  112 . A biasing mechanism, such as a spring  186  is configured to be captured between the flange  184  and the shoulder  146  of the sheath  120 . The spring  186  is configured to surround an exterior of the housing  112 . The spring  186  is used to press the sheath  120  in a forward direction relative to the housing  112 . The spring  186  is used to bias the sheath  120  to the blocking position after the sheath  120  is released from the cocked position. Other types of biasing mechanisms other than a spring may be used in alternative embodiments. 
         [0036]    The ejector  130  includes a head  190  and a post  192  extending forward from the head  190 . The post  192  is configured to extend through the housing  112  into receptacle  114 . The post  192  is configured to engage the insert  104  to eject or release the insert  104  from the receptacle  114  when the ejector  130  is actuated. In an exemplary embodiment, a biasing mechanism, such as a spring  194  is configured to be positioned between the head  190  and a portion of the housing  112 . The spring  194  may be biased against a front surface  196  of the head  190  to generally press the ejector  130  in a rearward direction. In use, the spring force of the spring  194  may be overcome as the ejector  130  is pressed and actuated to release the insert  104  from the housing  112 . In an exemplary embodiment, the ejector  130  includes a flange  198  at the front of the head  190 . The spring  194  may be biased against the flange  198 . The sheath latches  170  may be biased against the flange  198 . 
         [0037]    Each sheath latch  170  includes a main body  200  having pins  202  extending from the main body  200 . The sheath latch  170  includes a sheath arm  204  extending from one side of the main body  200  and an ejector arm  206  extending from the opposite side of the main body  200 . The sheath arm  204  is configured to engage the sheath  120 . For example, the sheath arm  204  may be received in the pocket  150  in the sheath  120 . The ejector arm  206  is configured to engage the ejector  130 . For example, the ejector arm  206  may engage the flange  198 . 
         [0038]    The sheath latches  170  are received in the rear openings  166  and may be pivoted about the pins  202 . The sheath latches  170  are used to hold the sheath  120  in the cocked positioned. In an exemplary embodiment, the ejector  130  is used to hold the sheath latches  170  in the latched position to hold the sheath  120  in the cocked position. When the ejector  130  is released, the sheath latches  170  may be moved to unlatched positions allowing the sheath  120  to move from the cocked position to the blocking position. An exemplary operation of the magnetic coupler  102  is described in further detail below. 
         [0039]      FIG. 6  is a cross sectional view of the magnetic coupler  102  and insert  104  showing the magnetic coupler  102  cocked and ready to receive the insert  104 .  FIG. 7  is a cross sectional view of the magnetic coupler  102  and insert  104  showing the insert  104  locked in the magnetic coupler  102 . 
         [0040]    In the cocked positioned ( FIG. 6 ), the sheath  120  is pulled rearward relative to the housing  112  and the sheath latches  170  are in latched positions engaging the sheath  120  and holding the sheath  120  in the cocked positioned. The ejector  130  is actuated and pushed forward relative to the housing  112 . The ejector  130  engages the sheath latches  170  and holds the sheath latches  170  in the latched positions. 
         [0041]    In an exemplary embodiment, the magnetic coupler  102  includes a magnet  210  held in the housing  112 . The magnet  210  is positioned proximate to the receptacle  114 . The magnet  210  is used to magnetically attract the insert  104  into the receptacle  114 . In an exemplary embodiment, the magnet  210  may be used to magnetically attract the ejector  130  and to hold the ejector  130  in a forward or actuated position. Optionally, the ejector  130  may hold a magnet  212  that is magnetically attracted to the magnet  210 . For example, the magnets  210 ,  212  may have opposite polarity such that the magnet  210  is used to hold the ejector  130  in the forward position. 
         [0042]    The ejector  130  engages the ejector arms  206  of the sheath latches  170 . For example, the flange  198  may press against the ejector arms  206  causing the sheath latches  170  to rotate outward to the latched position. As the sheath latches  170  rotate outward, the sheath arms  204  extend outward from the rear openings  166  of the housing  112  into the pockets  150  of the sheath  120 . Edges  220  of the ejector arms  206  engage corresponding shoulders  222  in the pockets  150 . The sheath  120  is locked and restricted from moving from the cocked position by the sheath latches  170 . Until the sheath latches  170  are rotated back into the rear openings  166 , the sheath  120  is held in the cocked position. 
         [0043]    The sheath latches  170  are able to rotate back into the rear openings  166  to the unlatched positions (shown in  FIG. 7 ) when the ejector  130  is released to provide clearance for the ejector arms  206  to extend into the ejector chamber  178 . In an exemplary embodiment, the ejector  130  is moved from the forward position (shown in  FIG. 6 ) to the rearward position (shown in  FIG. 7 ) by the insert  104 . When the insert  104  is loaded into the receptacle  114 , a plug end  230  of the insert  104  engages the post  192  and presses the post  192 , and thus the ejector  130 , in a rearward direction out of the receptacle  114  and rearward in the ejector chamber  178 . The ejector  130  is automatically released when the insert  104  is drawn into the receptacle  114  by the magnet  210 . When the ejector  130  is released, the sheath  120  is allowed to release to the blocking position (shown in  FIG. 7 ). The spring  186  forces the sheath  120  forward to the blocking position. When the head  190  is moved rearward in the ejector camber  178 , a clearance space  232  is defined in the ejector chamber  178  for the sheath latches  170 . The sheath latches  170  are able to rotate inward such that the ejector arms  206  are positioned in the clearance space  232 . As the sheath latches  170  rotate inward, the sheath arms  204  are transferred into the rear openings  166  and the housing  112 . The sheath arms  204  are moved out of the pockets  150  and out of the way of the sheath  120  to allow the sheath  120  to move from the cocked position (shown in  FIG. 6 ) to the blocking position (shown in  FIG. 7 ). 
         [0044]    In the blocking position, the shoulder  146  of the sheath  120  is aligned with the front openings  164  in the housing  112  and the insert latches  168  held in the front openings  164 . The shoulder  146  of the sheath  120  blocks the insert latches  168  from moving radially outward from the front openings  164 . The insert latches  168  are blocked from moving to the clearance position. The insert latches  168  are held in the locking positions, thus locking the insert  104  in the receptacle  114 . In an exemplary embodiment, the insert  104  includes a circumferential groove  234  in a side of the plug end  230 . The insert latches  168  are received in the grove  234  to lock the insert  104  in the quick connect receiver  110  defined by the housing  112 . Optionally, the insert  104  may include a plurality of grooves rather than a single circumferential groove. The insert latches  168  may be received in corresponding grooves to lock the position of the insert  104  relative to the housing  112  and to limit rotation  104  relative to the housing  112 . In the illustrated embodiment, the circumferential groove  234  allows the insert  104  to rotate within the receptacle  114 . 
         [0045]    In the locked position (shown in  FIG. 7 ), the sheath  120  blocks the insert latches  168  from moving to the clearance position. Additionally, the sheath  120  blocks the sheath latches  170  from rotating from the unlatched positioned (shown in  FIG. 7 ) to the latched position (shown in  FIG. 6 ). The interior wall  148  of the sheath  120  stops the sheaths latches  170  from rotating outward. The ejector arms  206  thus block the ejector  130  from being actuated and pressed forward. The insert  104  is unable to be ejected from the receptacle  114  by the ejector  130  until the sheath  120  is released and moved to the cocked positioned. 
         [0046]    Alternatively, the sheath latches  170  may be able to rotate outward even with the sheath  120  in the blocking position. Optionally, the pockets  150  may be aligned with the sheath arms  204  when the sheath  120  is in the blocking position such that, as the ejector  130  is pressed forward and actuated, the ejector  130  may press against the ejector arms  206  to cause the sheath latches  170  to rotate outward. As the sheath latches  170  rotate outward, the sheath arms  204  engage the sheath  120 , such as the shoulder  222 , and cause the sheath  120  to move rearward to the cocked positioned. Actuation of the ejector  130  may thus cause the sheath  120  to be cocked. 
         [0047]      FIG. 8  is an exploded view of a magnetic coupler  302  formed in accordance with an exemplary embodiment. The magnetic coupler  302  is similar to the magnetic coupler shown in  FIG. 5 ; however the magnetic coupler  302  includes different types of latches to cock the magnetic coupler and to hold an insert therein. For example, the magnetic coupler  302  includes latches  304  used to replace both the insert latches  168  and the sheath latches  170  (both shown in  FIG. 5 ). The magnetic coupler  302  includes a quick connect receiver  310  configured to receive the insert  104  (shown in  FIG. 1 ). The quick connect receiver  310  defines a female section of a magnetic coupler system. 
         [0048]    The magnetic coupler  302  includes a housing  312  having a receptacle that receives a plug end of the insert  104  therein. The magnetic coupler  302  includes an outer sheath  320  slidably coupled to and surrounding the housing  312 . The sheath  320  is movable between a cocked positioned and a blocking position. The latches  304  are used to secure the sheath  320  in the cocked position. For example, tabs  322  of the latches  304  may be positioned at a front of the sheath  320  to hold the sheath  320  in the cocked position. The latches  304  may be released, such as by an ejector  330 , when the insert  104  is loaded into the receptacle. For example, the latches  304  may be rotated until the tabs  322  clear the front of the sheath  320 . When the latches  322  are rotated, the latches  322  may latch onto the insert  104  and secure the insert  104  in the receptacle. In the blocking position, the outer sheath  320  blocks the latches  304  from moving outward or unlatching, thus securing the insert  104  in the receptacle. 
         [0049]    The ejector  330  may be actuated to eject the insert  104  from the receptacle. As the ejector  330  is actuated, the latches  304  may be rotated outward against the sheath  320 . The latches  304  may cause the sheath  320  to move rearward form the blocking position to the cocked position. Pressing of the ejector simultaneously causes the sheath  320  to move from the blocking position, the latches  304  to rotate outward, and the insert  104  to be ejected out of the receptacle. 
         [0050]    The latches  304  define quick connect features of the magnetic coupler  302  that are used to retain the insert  104  in the receptacle. The latches  304  are movable, for example rotatable, relative to the housing  312  between a locking position and a clearance position. The latches  304  are configured to engage and lock the insert  104  in the receptacle in the locking position. The insert  104  is able to be removed from the receptacle when the latches  304  are in the clearance position. In an exemplary embodiment, the latches  304  may be spring biased toward the clearance position. A spring coupled to the latches  304  may press the latching ends of the latches  304  outward away from the receptacle. The latches  304  may be rocker latches rocking into and out of the receptacle. Other types of latches may be used in alternative embodiments. 
         [0051]    The latches  304  include ramped or wedge-shaped posts that are thicker near the top and thinner near the bottom. As the ejector  330  rides vertically up and down inside the housing  312 , the ejector  330  engages the wedge-shaped posts and causes the latching ends of the latches  304  to rock into and out of the receptacle. For example, when the ejector  330  is released or moved rearward (e.g. upward in the orientation shown in  FIG. 8 ), the ejector  330  forces the latches  304  to press inward into the receptacle. The ejector  330  may be released by the insert  104  as the insert  104  is drawn into the receptacle by the magnet. When the ejector  330  is actuated or pressed forward (e.g. downward in the orientation shown in  FIG. 8 ), more clearance is provided between the ejector  330  and the wedge-shaped posts due to the shape of the latches  304 . The springs cause the latching ends of the latches  304  to pivot outward, thus unlatching the insert  104 . The post of the ejector  330  presses the insert  104  out of the receptacle against the magnetic force. 
         [0052]      FIG. 9  is an exploded view of a magnetic coupler  402  formed in accordance with an exemplary embodiment.  FIG. 10  is a cross-sectional view of the magnetic coupler  402 . The magnetic coupler  402  is similar to the magnetic coupler  102  shown in  FIG. 5 ; however the magnetic coupler  402  includes different types of springs  404  to support the insert therein. Like components of the magnetic coupler  402  are identified with like reference numerals of the magnetic coupler  102 . 
         [0053]    The springs  404  replace the spring  186  (shown in  FIG. 5 ). The springs  404  are captured between the flange  184  of the housing  112  and the shoulder  146  of the sheath  120 . The springs  404  are used to press the sheath  120  in a forward direction relative to the housing  112 . The springs  404  are used to bias the sheath  120  to the blocking position after the sheath  120  is released from the cocked position. 
         [0054]    It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means—plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.