Abstract:
A cord tensioning device has three modes of operation: a tightening mode, a release to loosen and then hold mode, and a release mode for relieving all tension in the cord. In the tightening mode, the shape of ratchet pawls and ratchet teeth allow a cord winding spool to rotate in only a tightening direction. In the release to loosen and then hold mode, an actuator associated with the knob releases the ratchet pawl from the ratchet teeth in a reverse direction, but upon release of the knob, the pawl re-engages the ratchet teeth to prevent further loosening. In this manner, the tension can be incrementally loosened. In the release mode, the pawls are disengaged from the ratchet teeth, even after release of the knob, and the spool can continue to rotate within the base when an external tension is applied to the cord.

Description:
REFERENCE TO GOVERNMENT FUNDING 
       [0001]    This invention was made with Government support under Contract No. W911QY-11-C-0046, awarded by the U.S. Army Material Command, a division of the United States Department of Defense. The Government has certain rights in this invention. 
     
    
     FIELD OF THE INVENTION 
       [0002]    Aspects of the invention relate to cord tensioning devices for use in tightening cords or laces used in lacing or strapping systems. 
       DISCUSSION OF THE RELATED ART 
       [0003]    It is known to provide a reel for tightening laces to close closure flaps of shoes, such as disclosed in U.S. Pat. Nos. 5,042,177 or 7,584,528. A cord reel is known to provide a helmet with an adjustable safety strap, such as disclosed in U.S. Pat. No. 6,026,798. 
         [0004]    In U.S. Pat. No. 6,026,798, a turn lock fastener is disclosed. This turn lock fastener includes a flat housing and a rotating knob disposed on top of the housing which can be rotated relative to the housing. Two pull cords pass out of the housing on opposite sides of the housing and are connected to helmet straps. A rotary actuator construction inside the housing allows the helmet strap to be tightened or released by turning a rotating knob. The rotary actuator is used to turn the cord wheel, on which ends of the cords are wound, in one direction or the other such that by turning the rotating knob the effective length of pull cords can be modified in opposite directions. 
       SUMMARY 
       [0005]    An exemplary embodiment of the present application provides a cord tensioning reel having three modes of operation: a ratchet-to-tighten mode, a release-ratchet-to-loosen-and-then-hold mode, and a total release mode for relieving all tension in the cord. In the ratchet-to-tighten mode, the shape of at least one ratchet pawl and ratchet teeth allow a cord winding spool to rotate in a tightening direction upon the application of external torque. In the release-ratchet-to-loosen-and-then-hold mode, an actuator associated with the knob releases the ratchet pawl from the ratchet teeth upon an external torque to the knob in a reverse direction. Upon release of the torque on the knob in the reverse direction, the pawl re-engages the ratchet teeth to prevent further loosening, e.g., the pawl holds the tension from further loosening. In this way the tension can be incrementally loosened. In the total release mode, the pawl is disengaged from the ratchet teeth, even after release of the knob, and the spool can freewheel within the base when an external tension is or is not applied to the cord. 
         [0006]    According to this embodiment, the apparatus includes a knob having at least one downward extending actuator, a cord spool and a pawl ring that can engage with the spool for mutual rotation. The pawl ring is axially captured by the knob and rotationally engaged by the actuator to be forcibly rotated by the knob but with a loss in the degree of rotation between the knob and the pawl ring. The apparatus includes a base having ratchet teeth engaged by the pawl ring to allow relative rotation between a subassembly comprising the knob, pawl ring and spool with respect to the base when the knob rotates in a tightening direction and to prevent reverse rotation and cord loosening once tightened. The apparatus allows reverse rotation after the lost motion rotation is taken up, by allowing the subassembly of the knob, pawl ring and spool to rotate relative to one another in a reverse direction, a loosening direction, with respect to the base by torque applied to the knob. 
         [0007]    The pawl engages the ratchet teeth and slips on the ratchet teeth when rotated in a cord tightening direction when a torque is applied to the knob by the actuator applying a tangential force to the pawl ring. When the knob is turned in a reverse, loosening direction, the actuator deflects the pawl from the ratchet teeth to allow rotation of the pawl ring and engaged spool with respect to the base in a loosening direction. Release of the applied loosening direction torque on the knob allows the pawl to snap back into engagement with the ratchet teeth and holds the selected tightening state of the spool with respect to the base. 
         [0008]    The apparatus can also include a retainer that is secured to the base and which captures the knob onto the base. The retainer includes a body that has two grooves to provide a selectable axial position of the knob with respect to the base. In the first axial position, the apparatus is set to function in either the ratchet-to-tighten mode or the release-ratchet-to-loosen-and-then-hold mode as described herein. In a second axial position, the pawl ring is released from the ratchet teeth and/or the pawl ring is released from the spool, and the spool is free to turn within the base. 
         [0009]    The reel of the present application is particularly useful for tension helmet straps, particularly for military helmets, wherein a user can tighten or loosen helmet straps with one hand. 
         [0010]    Numerous other advantages and features will become readily apparent from the following detailed description of various embodiments and the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is an exploded upper perspective view of a cord tensioning reel according to one embodiment of the invention; 
           [0012]      FIG. 2  is an exploded lower perspective view of the cord tensioning reel of  FIG. 1 ; 
           [0013]      FIG. 3  is a sectional view of the apparatus of  FIG. 1  after assembly and in a first operating state; 
           [0014]      FIG. 4  is a sectional view of the apparatus of  FIG. 3  in a second operational state; 
           [0015]      FIG. 5  is a sectional view taken along line  5 - 5  of  FIG. 3  in the first operational state with the knob in a tightening mode; 
           [0016]      FIG. 6  is a sectional view taken along line  5 - 5  of  FIG. 3 , in the first operational state with the knob in a loosening mode; 
           [0017]      FIG. 7  is a sectional view taken along line  7 - 7  of  FIG. 5  but only showing a base of the apparatus; 
           [0018]      FIG. 8  is a fragmentary sectional view taken along lines  8 - 8  of  FIG. 5 ; 
           [0019]      FIG. 9  is a sectional view showing the apparatus of one embodiment of the invention applied to a helmet retention system; 
           [0020]      FIG. 10  is a fragmentary rear view of the helmet retention system shown in  FIG. 9 ; 
           [0021]      FIG. 10A  is a perspective view of a reel of the helmet retention system of  FIG. 9 ; and 
           [0022]      FIG. 10B  is a front view of a contact strap and loop of the helmet retention system of  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    The present inventors have recognized a need for a cord tensioning reel that is compact, cost-effectively manufactured and assembled. The present inventors have recognized a need for a cord tensioning reel for military helmets or other helmets that can be used to adjust the fit and tension of a helmet strap. The present inventors have recognized a need for a cord tensioning reel that can be used in three modes of operation: a ratchet-to-tighten mode, a release-ratchet-to-loosen-and-then-hold mode, and a total release mode for relieving all tension in the cords. 
         [0024]    There are shown in the drawing and will be described herein in detail specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification and is not intended to limit the invention to the specific embodiments illustrated.  FIGS. 1 and 2  illustrate a cord tensioning reel  20  comprising a retainer  24 , a knob  26 , a pawl ring  28 , a spool  32  and a base  36 . 
         [0025]    The retainer  24  includes a disk-shaped retainer flange  42  and a retainer body  46  extending downward from the flange. The retainer body  46  is substantially hollow and cylindrical and has a lower annular groove  50  and an upper annular groove  52  on an outside of the retainer body  46 . The grooves  50 ,  52  can have a V.-shaped cross-section. A mounting hole  56  extends centrally through the flange  42 . The body includes a cylindrical cavity  58  that is open to the mounting hole  56 . 
         [0026]    Knob  26  includes a disc-shaped top wall  63  and a slotted or knurled cylindrical side wall  64  extending downward from the top wall  63 . The top wall  63  includes a central opening  66 . An annular bottom lip  67  extends radially inward from an end of the sidewall  64 . 
         [0027]    Extending downward from the top wall  63  around the opening  66  are lifting arms  70  and detent arms  76 . Also extending downward from the top wall  63  are bosses or actuators  82 . The bosses  82  are arranged radially spaced from the opening  66  and the lifting arms  70  and the-detent arms  76 . The members  70 ,  76 ,  82  all have a circular curvature about the center of the opening  66 . 
         [0028]    The pawl ring  28  includes a base ring  94  having a central opening  96 . A plurality of spaced-apart teeth  106  extend downward from the base ring  94 . Teeth  106  are spaced apart evenly around the circumference of the base ring  94 . On top of the base ring  94  are three pawl members  110   a,    110   b,    110   c.    
         [0029]    Each pawl member  110   a,    110   b,    110   c  includes a pawl base  112 , a flexible pawl arm  114  extending from the pawl base  112  and a pawl head  116  extending from the flexible pawl arm  114 . The three pawl members  110   a,    110   b,    110   c  curl from pawl base  112  to pawl head  116  concentrically around a center of the opening  96  in a common rotary direction. 
         [0030]    The spool  32  includes an annular top wall  152  and a substantially circular bottom wall  156 . An annular wall  158  connects the walls  152 ,  156  and forms a cord winding groove  162  on outside of the annular wall  158 . The bottom wall  156  includes slotted portions  166   a,    166   b,    166   c  that allow for anchoring the cords  205   a,    205   b  ( FIG. 3 ) wound on the spool  32 . The bottom wall  156  includes a central opening  170 . Within the annular walls  152 ,  158  a plurality of teeth  180  extend upward from the bottom wall  156 . The teeth  180  are evenly spaced around a circumference of the annular wall  158 . The teeth  180  are configured and spaced to mesh with the teeth  106  of the pawl ring when the pawl ring  28  is positioned against the spool  32 . 
         [0031]    Base  36  includes a bottom circular wall  204  and a surrounding cylindrical sidewall  206  that extends upward from the bottom wall  204 . The bottom wall  204  includes cylindrical bores  204   a,    204   b  for cords  205   a,    205   b  to enter/exit the base  36  and to be wrapped around the spool  32 . 
         [0032]    The cords  205   a,    205   b  are wound in a same rotary direction on the spool such that clockwise turning of the spool draws both cords  205   a,    205   b  into the base  36  and counterclockwise rotation of the spool dispenses the cords  205   a,    205   b  out of the base  36 . A plurality of ratchet teeth  210  extend radially inward from an inside surface of the sidewall  206 . The teeth  210  are evenly spaced around the circumference of the sidewall  206 . A cylindrical attachment boss  220  extends upward from the bottom wall  204 . Boss  220  includes a central bore  226  that can accept a screw  227  to hold together the entire assembled reel  20 . 
         [0033]      FIGS. 3-5  illustrate the reel  20  in an assembled state. Spool  32  having the cords  205   a,    205   b  wound thereon is placed over the boss  220  and inside the base  36  with the attachment boss  220  extending through the spool opening  170 . The cords  205   a,    205   b  are threaded through two holes  204   a,    204   b  in the base bottom wall  204 . The spool  32  is now freely rotatable on the attachment boss  220 . Then, the pawl ring  28  is placed over and onto the spool  32  and the pawl ring teeth  106  mesh with the spool teeth  180  and pawl heads  116  mesh with the base ratchet teeth  210 . 
         [0034]    A subassembly comprising the retainer  24  and knob  26  are pressed down onto the pawl ring  28  and the base  36 . The attachment boss  220  fits into the cavity  58  of the retainer  24 . The screw  227  attaches the retainer  24  to the base  36 . As the knob  26  is pressed onto the base  36 , the lift arms  70  deflect radially inward due to sliding between the opposing tapered surfaces  70   a,    94   a  on, respectively, the lift arms  70  and pawl base ring  94 . When the lift arms  70  have deflected sufficiently inward as the knob  26  is pressed down onto the pawl ring, lift arm heads  70   b  clear the pawl base ring  94  and snap back radially outward to underlie the pawl ring  94 . Each boss or actuator  82  fits between a flexible arm  114  of a respective pawl  110   a,    110   b,    110   c  and the ratchet teeth  210 . 
         [0035]    As illustrated in  FIG. 3 , each detent arm  76  includes a rounded head  76   a  that snaps into a selectable one of the grooves  50 ,  52 . The opening  66  through the top wall of the knob is large enough and deep enough that the flange  42  can move in relative axial motion through the opening between the two positions shown in  FIG. 3  and  FIG. 4  as the knob  26  is raised and lowered with respect to the base  36 . 
         [0036]    In the position shown in  FIG. 3 , the detent head  76   a  snaps into the lower groove  50 . In the position shown in  FIG. 4 , the knob  26  has been pulled up with respect to the base  36  and the detent head  76   a  has snapped into the upper groove  52 . In the position shown in  FIG. 3 , the pawl heads  116  are engaged to the ratchet teeth  210  and the pawl ring teeth  106  mesh with the spool teeth  180 . In the position shown in  FIG. 4 , the pawl heads  116  are pulled up to non-engagement with the ratchet teeth  210  and the pawl ring teeth  106  are pulled up to non-engagement with the spool teeth  180 . The pawl ring  28  is pulled up by the lift arms  70  via the lift arm heads  70   b.  The detent heads  76   a  snap into the groove  52  and a stop  70   c  provided on the inside of each lift arm  70  abuts an underside  42   a  of the retainer flange  42  to prevent further upward travel of, and separation of, the knob  26  from the base  36 . 
         [0037]    As understood from  FIG. 5 , for clockwise turning of the knob  26  with respect to the base  36 , the pawl flexible arms  114  deflect radially inwardly as the pawl heads  116  slip over the ratchet teeth  210 . Each pawl head  116  has a sloping surface  116   a  that slides over a sloping surface  210   a  of the ratchet teeth. 
         [0038]      FIG. 5  illustrates the knob ready to turn further in a tightening direction, clockwise. The bosses  82  abut a shoulder  112   a  of each respective base  112 . Further rotation of the knob  26  presses the bosses  82  against the shoulders  112   a  and forces rotation of the pawl ring  28  and the spool  32 , by the engagement of the teeth  106 ,  180 , in a clockwise direction as the pawl heads  116  slip over the teeth  210 . 
         [0039]      FIG. 6  illustrates the knob  26  rotated counterclockwise a short rotational angle from the positions shown in  FIG. 5 , to a position where the steep surfaces  116   b  of the pawl head  116  is clear from a steep surface  210   b  of the ratchet teeth  210  to allow counterclockwise rotation of the pawl ring and spool with respect to the base. The bosses  82  press against a sloping backside  114   a  of the flexible arms  114  to deflect the pawl heads  116  out of engagement with the ratchet teeth  210 . 
         [0040]    In operation, with the knob  26  pressed down into the configuration of  FIG. 3 , clockwise turning of the knob  26  with respect to the base  36  causes the pawl ring  28  and spool  32  to rotate clockwise and the cords are drawn into the base  36  as the cords are wound on the spool  32 . Once the cords are tightened a desired amount, the steep opposing surfaces  116   a,    210   a  of the pawl heads and the ratchet teeth respectively, prevent reverse rotation of the pawl ring and loosening of cords when the knob is released by the user. 
         [0041]    With the apparatus still in the orientation of  FIG. 3 , a counterclockwise rotation of the knob  26  with respect to the base  36 , after passing a small angle of lost motion, will rotate the pawl ring  28  and spool  32  to loosen the cord. Release of torque on the knob allows the pawl heads  116  to snap back into engagement with the ratchet teeth  210  and prevents further loosening of the cord. 
         [0042]    A third operational mode occurs when the knob  26  is pulled up with respect to the base  36  into the orientation of  FIG. 4 . In this orientation, the spool is effectively disengaged from the base and/or from the pawl ring and is freely rotatable on the attachment boss. Thus, tension is released and the cords can be manually pulled out of the base, rotating the spool within the base. 
         [0043]      FIGS. 7 and 8  illustrate how the cords  205   a,    205   b  enter/exit the base  36  and are wound on the spool  32 . The bottom wall  205  of the base  36  includes the cylindrical bores  204   a,    204   b.  The bores  204   a,    204   b  are located radially outside the circumference of the spool  32 . The bores  204   a,    204   b  are open to a curved cord feed channel  204   c,    204   d  which respectively guide the two cords  205   a,    205   b.  The feed channels  204   c,    204   d  are each open to a respective window  204   e,    204   f  into an interior portion of the base  36  and exposed to the spool to be wound thereon. The bore/feed channel/window combinations  204   a,    204   c,    204   e  and  204   b,    204   d,    204   f  each guide a respective cord  205   a,    205   b  into/out of the base  36  to be wound on the spool and each allow a right angle turn of the cord from its entry into the bottom wall to its approach and winding on the spool. 
         [0044]    The present embodiment of a tension reel is particularly effective for setting tension in a strap system for a helmet. 
         [0045]    A helmet retention system  600  may be used with helmet  90  shown in  FIGS. 9 ,  10 ,  10 A and  10 B. The helmet retention system is substantially a mirror image across the center, vertical mid-plane of the helmet. The helmet retention system  600  comprises a front strap system  610  and a lower strap system  620 . The front strap system  610  has a first reeling cord  616 , a first contact strap  612 , and a first reel  631 . The lower strap system  620  has a second reeling cord  626 , a second contact strap  622 , and a second reel  632 . The first and second reels can be housed in a reel housing  630 . The reel housing  630  is enclosed in a soft armor neck pad for contacting the rear of a user&#39;s neck and/or head. 
         [0046]    The first and second reels  631 ,  632  may be configured similarly to the reel  20  described in  FIGS. 1-8 . 
         [0047]    Referring to the front strap system  610 , the first reeling cord  616  is anchored to the helmet at a forward location adjacent a user&#39;s temple by a front anchor  643 . The front anchor may be located between a user&#39;s eye and a user&#39;s ear, such as shown in  FIG. 9 . A downward extending portion  616   a  extends downward and is fed through a loop  614  attached to a first contact strap  612 . After the loop  614  an upward extending portion  616   b  extends upward from the loop adjacent to, and in some versions substantially parallel to, the downward extending portion  616   a  until the first reeling cord reaches a first front system block  641 . The first reeling cord slides over the first block  641  and thereafter the first reeling cord extends rearward along a rearward extending portion  616   c  toward the rear of the helmet on a slightly declining angle to second front system block  642 . The reeling cord slides over the second block  642  and downward and forward to a third block  645  then rearward to the reel housing  630  and then into the first reel  631  with portion  616   d.    
         [0048]    The reels  631 , 632  are substantially the same and an exemplary reel  631 ,  632  is shown in  FIG. 10A . The reel  631  is circular and has a channel  635  defined by the outer disk walls  637 ,  638 . The channel is for reeling, holding, and releasing the reeling straps  616 ,  626 . The reel  631  comprises a center hub  636  about which a knob  26  ( FIG. 2 ) of the reel can be turned. The reel  631  may also include an anchor where a reel cord is held at someplace along a length of the reel cord that is not an end of the reel cord. In one embodiment, the reel cord is anchored at a midpoint along its length. Turning the knob  26  of the reel  631  in a first direction draws both ends of the reel cord closer to the reel and thereby increase the tension on the reel cord and the associated contact strap. Turning the reel knob in a second direction, opposite of the first direction, will spool out the reel cord in both direction and thereby release tension on the reel cord and the corresponding contact strap. 
         [0049]    As the reel cord enters the reel  631  at cord portion  616   d,  it is anchored as just described, and then may be wound around the reel a number of times depending on the position of the reel, and a reel cord  616   e  will extend out of the reel along to the opposite side of the helmet as shown in  FIG. 10A . On the opposite side of the helmet, the reeling cord  616  continues in a configuration which is a mirror image to that shown in  FIG. 9  and the reel cord end is anchored in place in a mirror image location opposite that shown in  FIG. 9 , in some embodiments. Opposite ends of the reel cord may be anchored to the helmet in opposite front temple areas of the helmet. Likewise, the first contact strap continues under a user&#39;s chin as shown in  FIG. 9  to engage the first reel cord on the opposite side. 
         [0050]    The front strap system  610  is configured to increase or decrease the downward tension in a forward area between a helmet  10  and the user&#39;s head. Turning the first reel knob moves the reel cord and the position of the loop  614  to move up or down in the direction H shown in  FIG. 9  depending on the direction that the first reel knob is turned. 
         [0051]    The lower strap system  620  operates similarly to that of the front strap system  610  but the lower strap system  620  may be positioned differently than the front strap system. The second reel cord  626  may be anchored at a rear position of the helmet by a rear anchor  644 . The anchor  644  may be positioned on the helmet behind the rear of a user&#39;s head when viewed from the side as shown in  FIG. 9 . The second reel cord  626  extends from the anchor  644  downward along a downward extending portion  626   a  and forward to a first lower system block  646 . The first block may be positioned on the helmet or on the reel housing. The second reel cord then extends forward toward a user&#39;s ear, on a forward portion  626   b  to a loop  624  of the second contact strap  622 . The second reel cord  626  loops back around loop  624  and extends rearward along a rearward portion  626   c,    626   d  to enter the second reel  632  (not shown). The rearward portion  626   c  travels adjacent, and some configurations, substantially parallel to the forward portion  626   b.    
         [0052]    As the second reel cord enters the reel  632  at reel portion  626   d  it may be wound around the reel a number of times depending on the position of the reel, and reel cord  626   e  will extend out of the reel along to the opposite side of the helmet as shown in  FIG. 10A . On the opposite side of the helmet, the reeling cord  626  continues in a configuration which is a mirror image to that shown in  FIG. 9  and the reel cord end is anchored in place in a mirror image location opposite that shown in  FIG. 9 , according to some embodiments. Opposite ends of the reel cord may be anchored to the helmet in opposite rear areas of the helmet. Likewise the second contact strap is configured to continue over the front of a user&#39;s chin as shown in  FIG. 9  to engage the second reel cord on the opposite side. The open area chin cup  621  configuration provide by the first contact strap  612  and the second contact strap  622  and the gap there-between below the contact or cross point  611  secures the contact with the user&#39;s chin while leaving an open area of the users chin for a more comfortable fit. 
         [0053]    The lower strap system  620  is configured to increase or decrease the downward tension in a rear area between a helmet  90  and the user&#39;s head. Turning the second reel knob moves the second reel cord and causes the position of the loop  624  to move substantially forward or backward in the direction I shown in  FIG. 9  depending on the direction that the second reel knob is turned. 
         [0054]    Each of the front strap system  610  and the lower strap system  620  are adjustable by turning the knobs of the corresponding reels  631 ,  632 . Therefore, in some embodiments, the helmet retention system  600  may be adjusted by a user using only one hand. 
         [0055]    The cords  616   d,    626   d  and  616   e,    626   e  can be guided laterally across the back side of the helmet (not shown) to enter the respective cylindrical bores  204   a,    204   b  (see  FIG. 2 ) on the back side of the reels  631 ,  632 . 
         [0056]    From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred.