Patent Publication Number: US-8984719-B2

Title: Closure system

Description:
PRIORITY CLAIM AND INCORPORATION BY REFERENCE 
     The present application is a continuation of U.S. patent application Ser. No. 12/355,675, filed Jan. 16, 2009 (entitled “CLOSURE SYSTEM”), which claims the benefit of U.S. Provisional Patent Application No. 61/022,045, filed Jan. 18, 2008 (entitled “CLOSURE SYSTEM”). 
     The present application incorporates by reference the entire disclosure of U.S. patent application Ser. No. 12/355,675, filed Jan. 16, 2009 (entitled “CLOSURE SYSTEM”) and the entire disclosure of U.S. Provisional Patent Application No. 61/022,045, filed Jan. 18, 2008 (entitled “CLOSURE SYSTEM”). 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This disclosure relates to the field of closure systems. More specifically, this disclosure relates to methods and systems of cam assembly and strap based closure systems using a spiral. 
     2. Description of the Related Art 
     A significant problem with closure systems today is that they lack a self-locking mechanism. Creating closure systems that are infinitely adjustable and self-locking is especially problematic. Moreover, creating a closure system where the torque felt by the knob is constant is especially problematic. 
     Another problem is that closure systems create a force that pries the cam away from the strap, which lowers the strength of the system. Yet another problem is that closure systems do not prevent the strap from completely falling out of the cam assembly when the strap is loosened. 
     These inventions seek to address at least some of these problems. 
     SUMMARY OF THE INVENTION 
     Some embodiments of these inventions provide a cam assembly and strap based system for bringing two sides of an article together. The system may also be used to bring multiple sides of an article together, two objects together and/or multiple objects together and/or away from each other. In some embodiments, a cam assembly and strap based closure system may use a logarithmic spiral. When the user inserts the strap into the cam assembly and turns a knob, the strap is driven into the cam assembly. In some embodiments, the pins on the strap engage the cam spirals in the cam assembly. A track insert may pull the strap away from the cam to disengage the strap so that the cam spirals are engaged in reduced number of strap pins compared to the total number of strap pins within the cam assembly. 
     In some embodiments, one or more logarithmic spirals cause the strap pins to always be engaged at a constant angle, often self-locking. In addition to being self-locking, the system may be infinitely adjustable and the torque felt by the knob may be constant. The contact angle between the cam and the strap may be varied as desired. In some embodiments, lower contact angles may make the system self-locking. In some embodiments, more than one spiral may be used. Different spirals, such as Archimedean spirals, may be used in some embodiments. In some embodiments, higher contact angles may allow the strap to be driven into the cam assembly more rapidly. In some embodiments, secondary frictional elements, for example detents on the bottom or periphery of the cam or buttons, may be used to make the system self-locking even at higher contact angles. In addition, a detent system may be used to provide an audible click to provide an auditory indication of movement. 
     In some embodiments, the system may bring the strap pins into the cam assembly and in parallel to the cam for maximum strength and then use a guide component on a track insert that bends the strap away from the cam in a deliberate and controlled way. The guide component or bend back mechanism may be a tunnel and/or can be an S-shaped bend and/or an arc that pulls the strap away from the cam spirals that drive the strap pins. In some embodiments, the center portion of a spiral may be removed to allow room for this disengagement to occur. This guide component is particularly useful in providing the lowest possible height and/or profile of the housing. The guide component may also allow the strap to be fed into the cam assembly without catching on the cam. 
     In some embodiments, the system may be configured to prevent or obstruct the strap from completely feeding out of the cam assembly when the knob is driving the strap out of the cam assembly. For example, in some embodiments, once the end of the strap pins are reached, the strap may ratchet in place. Keeping the strap in the cam assembly maintains the position such that the knob may be turned to immediately drive the strap back into the cam assembly. This is particularly useful for avoiding having to manually push the strap into the cam assembly to engage the cam spirals. 
     In some embodiments, the system may be configured to allow rapid release and/or quick insertion of the strap for faster operation. The system may be configured to allow a user to pull up on a knob against, for example, a wave washer and/or spring, to disengage the cam from the strap. When the knob is released, the cam is biased back against the strap. If the cam is not aligned with the strap pins, then once the knob is turned the strap pins are reengaged. This is particularly useful to facilitate rapid release and/or quick insertion of the strap for faster operation of the closure system. In addition, in some embodiments, the system may be detented so that the knob and/or cam can be snapped into a release position and then snapped directly downward into a position to drive the strap. 
     In some embodiments, quick insertion may be accomplished by providing beveled strap pins and a biasing member such as a wave washer and/or spring. When the strap is inserted into the cam assembly, the cam can hop or pass over the beveled strap pins. The hop or pass over may be facilitated when the beveled strap pins are mated to a beveled cam spiral. This is particularly useful for allowing the closure to open slowly, but also allowing rapid advancement or insertion of the strap. In some embodiments, the tension side of the strap pins may be kept at approximately 90 degrees for maximum strength and retention. 
     In some embodiments, the system may be configured to manage overloading forces applied to the system for strength and safety. For example, by beveling the drive side of the strap pins and cam spirals, the knob and cam can be configured to pop up and release the strap to prevent overloading of the system at a predetermined load. This is particularly useful in, for example, helmet, headwear, or other clothing or accessory applications. 
     In some embodiments, the system may include an adjustment memory. The cam may be infinitely adjustable and can be left in a particular position for an ideal fit for a particular use. When the user releases a gross movement mechanism, for example, a clasp, buckle, hook, or latch, the adjustment or position of the strap within the cam is memorized or retained. The gross movement mechanism may allow some slack to be generated for release and may allow the closure system to be a fine adjustment that can be retained for adjusting the strap. The gross movement mechanism may be particularly useful, in some embodiments, for rapid release and/or quick insertion. 
     The system is particularly useful as a replacement for Velcro. Various applications include shoes, including zonal closures; sandals, including straps; helmets; medical braces; packs; tying down loads; protective pads, including shin guards and football pads; snowboard bindings; gloves; and belts. 
     In some embodiments, a cam assembly and strap based system for bringing two sides of an article together is provided. The system may include a housing adapted to receive a strap. In some embodiments, the housing includes a track insert configured to receive the strap. The strap may be adapted to feed into the housing and track insert and may include strap pins configured to engage in a cam. The cam may include at least one spiral. The cam may be configured to pull the strap pins. The system may further include a knob configured to rotate the cam. 
     In some embodiments, a method for drawing two objects towards each other is provided. The method may include providing a housing adapted to receive a strap. In some embodiments, the housing may include a track insert configured to receive the strap. The strap may be adapted to feed into the housing and track insert. The strap may include strap pins configured to engage in a cam. The method may further include configuring the cam to pull the strap pins, wherein the cam may include at least one spiral. The method may further include, providing a knob configured to rotate the cam. The housing, the cam, and the knob may be positioned on a first object. The strap may be positioned on a second object. The knob may be rotated to drive the strap into the housing to pull the first object and second object towards each other. 
     In some embodiments, a method for drawing two objects away from each other is provided. The method may include providing a housing adapted to receive a strap. In some embodiments, the housing may include a track insert configured to receive the strap. The strap may be adapted to feed into the housing and track insert. The strap may include strap pins configured to engage in a cam. The method may further include configuring the cam to pull the strap pins, wherein the cam may include at least one spiral. The method may further include, providing a knob configured to rotate the cam. The housing, the cam, and the knob may be positioned on a first object. The strap may be positioned on a second object. The knob may be rotated to drive the strap away from the housing to push the first object and second object away from each other. 
     Some embodiments of these inventions comprise a strap suitable for use in a cam housing, the strap useful for tightening an article, compressing an article, loosening an article, pulling two articles together, pushing two articles apart, pulling two sides of an article toward each other or pushing two sides of an article away from each other. The strap may comprise a proximal end, a distal end, spiral engaging members or strap pins near the proximal end, and between the proximal end and the first of the spiral engaging members a stop for impeding the strap&#39;s entrance into and exit from the cam housing. The stop may be configured to collapse to allow entrance into and/or exit from the cam housing given sufficient force applied to the strap in an appropriate manner. The strap may include one or more holes and one or more extensions extending in a plane with the strap such that one or more of the extensions collapse into the one or more holes to allow the strap to pass into or out of the cam housing. The extensions may alternatively extend in a plane different than the strap, for example they may extend upwards from the surface of the strap such that they, for example, contact a portion of the housing to impede the insertion of or withdrawal of the strap from the housing. These off-plane extensions would collapse substantially downward (if they extend upwards from the strap surface) or substantially upward (if they extend downward from the strap surface) to allow entrance into or exit from the housing. The one or more extensions may be angled or chamfered at their proximal and/or distal edges such that they promote some sliding with respect to the housing whereby they ultimately allow the strap to enter or exit the housing given sufficient force applied to the strap. In some embodiments, the angle or chamfer of the proximal edge of the extension less than the angle of the distal edge as measured from the edge or surface of the strap such that less force is required to compress the one or more extensions when the strap is inserted than when it is removed. Some embodiments include a chamfered surface on the first spiral engaging member wherein the angle of the chamfer is on the side of the spiral engaging member which faces the proximal end of the strap such that spirals attempting to engage this chamfered surface slide off the surface and the strap is not forced by the spirals out of the housing once all of the spiral engaging members are released from the spiral area of the housing. The leading chamfered surface may also allow for quick insertion of a strap into an appropriately configured housing. Some embodiments may comprise a stop as described above near the distal most spiral engaging member to prevent the strap from freely passing through the housing once the last or distal most spiral engaging member has passed through the spirals. This stop may be configured to completely prevent further movement of the strap through the housing, such as, for example, by including one or more outward extensions which cannot be compressed. Some embodiments may include a distal facing chamfered surface on the distal most spiral engaging member so that the spiral surface slides off of the distal most spiral engaging member once the strap has passed through the housing a pre-determined length. In some embodiments, the strap may comprise at its distal end a portion configured for attaching the distal end to an article. In some embodiments, this portion is configured as a hole for mating engagement with a hook or other device as shown, for example, in the figures. In some embodiments, the proximal end of the strap attaches to the housing while the distal end attaches to an article. In some embodiments, one or more of the spiral engaging members or strap pins include spiral engaging surfaces in substantially the same plane as one or both of the engagement surfaces of the spirals. Some embodiments of these inventions include an article having a strap with one or more of the features disclosed herein. These articles include, but are not limited to, shoes, boots, sandals, protective gear, compression straps, packs, backpacks, athletic gear, shin or other guards for various sports, gloves, hats, caps, helmets, hydration packs, etc. 
     Some embodiments of these inventions comprise a cam housing suitable for use with a strap, the housing useful for tightening an article, compressing an article, loosening an article, pulling two articles together, pushing two articles apart, pulling two sides of an article toward each other or pushing two sides of an article away from each other. The housing may comprise an inlet for allowing the insertion of a strap and an outlet to allow the strap to pass through the other side of the housing, wherein the inlet is on a different plane than the outlet. The housing may comprise a knob which may be coupled to one or more spirals, the knob/spiral combination configured to drive a strap through the housing in either direction. In some embodiments, the spirals are logarithmic spirals which maintain a constant contact angle with one or more portions of the strap as the strap moves into or out of the housing such that the strap is self locking in the housing, wherein the strap will not move into or out of the housing without rotation of the knob. In some embodiments, two spirals or spiral segments, three spirals or spiral segments, four spirals or spiral segments, five spirals or spiral segments or more spirals or spiral segments are included. Increasing the number of spirals or spiral segments increases the amount of strap that is taken into or pushed out of the housing per rotation of the spirals or spiral segments. The housing may comprise a strap pathway that insulates the strap from the article as the strap passes through the housing, the strap pathway comprising a floor near the bottom of the housing (closest to the article) on and/or over which the strap moves as it passes through the housing. The housing may comprise an insert separately formed from the housing which, when coupled to the housing, directs a strap entering the housing through the housing inlet, off the plane of the inlet, and toward the outlet of the housing which is on a different plane than the inlet. In some embodiments, the insert may be integrally formed with the housing rather than separately formed. In some embodiments, the housing comprises a knob coupled to one or more spirals, the knob configured to be displaced away from and back toward the housing to permit rapid insertion or release of a strap. In some embodiments, the housing and/or the knob include a detent or other member to hold the knob either away from or against or adjacent the housing. In some embodiments, the housing includes a biasing member which biases the knob and the spirals against or adjacent the housing. In some embodiments, the housing includes a detent or other member configured to hold the knob away from the housing against a bias. Some embodiments of these inventions include an article having a cam housing with one or more of the features described herein. These articles include, but are not limited to, shoes, boots, sandals, protective gear, compression straps, packs, backpacks, athletic gear, shin or other guards for various sports, gloves, hats, caps, helmets, hydration packs, etc. 
     Some embodiments of these inventions comprise a cam housing and a strap, the housing and the strap in combination useful for tightening an article, compressing an article, loosening an article, pulling two articles together, pushing two articles apart, pulling two sides of an article toward each other or pushing two sides of an article away from each other. In some embodiments, the cam housing comprises one or more of the features described herein. In some embodiments, the strap comprises one or more of the features described herein. Some embodiments are configured such that as the strap passes through the housing, it does not double up over itself. As such, in some embodiments there is only one layer of strap before engagement and during engagement of the cam housing and the strap. In some embodiments, the housing is attached to a portion of an article to be manipulated and not to the strap itself. In some embodiments, the strap and housing do not form a complete ring when engaged with a first end of the strap engaged with the housing and a second end of the strap remaining separate from the housing. In some embodiments, the housing does not ride on the strap. Some embodiments of these inventions include an article having a cam housing and a strap with one or more of the features described herein. These articles include, but are not limited to, shoes, boots, sandals, protective gear, compression straps, packs, backpacks, athletic gear, shin or other guards for various sports, gloves, hats, caps, helmets, hydration packs, etc. 
     Some embodiments of these inventions include a method of tightening an article, compressing an article, loosening an article, pulling two articles together, pushing two articles apart, pulling two sides of an article toward each other or pushing two sides of an article away from each other using a cam housing and a strap. In some embodiments, the cam housing comprises one or more of the features described herein. In some embodiments, the strap comprises one or more of the features described herein. In some embodiments, the combination of the cam housing and the strap comprise one or more of the features described herein. In some embodiments, the method comprises the step of turning a knob attached to the housing to drive the strap through the housing. Turning the knob causes one or more engagement surfaces of one or more spirals coupled to the knob to slidingly couple to one or more engagement surfaces of one or more spiral engaging members or strap pins on the strap, the sliding coupling pulling the strap into the housing or pushing the strap out of the housing causing tightening or compression of an article, loosening of an article, pulling two articles together, pushing two articles apart, pulling two sides of an article toward each other or pushing two sides of an article away from each other. In some embodiments, the method further comprises the step of first inserting the proximal end of the strap into the housing, wherein the strap has a stop near the proximal end which provides resistance making it relatively difficult to insert the strap into the housing such that an engagement surface on the first spiral engagement member can contact an engagement surface of one of the spirals inside the housing. The method including the strap being inserted into the housing with sufficient force to overcome the stop to bring the spiral engaging members into contact with the spirals inside the housing. In some embodiments, the knob is pulled away from the housing to allow easy insertion or removal of the strap. In some embodiments, the knob is movably biased toward the housing such that upon insertion of a strap into the housing, the strap comprising a chamfered surface on the leading or proximal most spiral engaging member causes the knob, and thereby any spirals coupled to the knob, to temporarily displace away from the housing to allow the strap to enter into the housing wherein the strap is in position to be pulled further into the housing by rotation of the knob after the knob moves back toward the housing. In some embodiments, these methods are used with respect to, for example, shoes, boots, sandals, protective gear, compression straps, packs, backpacks, athletic gear, shin or other guards for various sports, gloves, hats, caps, helmets, hydration packs, etc. 
     Neither this summary nor the following detailed description purports to define the inventions. These inventions are defined by the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features will now be described with reference to the drawings summarized below. These drawings and the associated description are provided to illustrate some embodiments of the inventions, and not to limit the scope of the inventions. 
         FIG. 1  illustrates a set of components for implementing a cam assembly and strap based closure system using a spiral from a perspective view, in accordance with some embodiments of the inventions. 
         FIGS. 2A ,  2 B, and  2 C illustrate the cam assembly and strap based closure system of  FIG. 1  from a side, top, and bottom view, in accordance with some embodiments of the inventions. 
         FIGS. 3A ,  3 B,  3 C, and  3 D illustrate the cam of  FIG. 1  from a top, bottom, and perspective views, in accordance with some embodiments of the inventions. 
         FIGS. 4A and 4B  illustrate the strap of  FIG. 1  from a perspective and top view, in accordance with some embodiments of the inventions. 
         FIGS. 5A ,  5 B, and  5 C illustrate the track insert of  FIG. 1  from a perspective, top, and side view, in accordance with some embodiments of the inventions. 
         FIGS. 6A ,  6 B,  6 C, and  6 D illustrate the housing of  FIG. 1  from a perspective, side, top, and bottom view, in accordance with some embodiments of the inventions. 
         FIG. 7  illustrates the knob of  FIG. 1  from a perspective view, in accordance with some embodiments of the inventions. 
         FIG. 8  illustrates the overmold of the knob of  FIG. 7  from a bottom view, in accordance with some embodiments of the inventions. 
         FIGS. 9A and 9B  illustrate the undermold of the knob of  FIG. 7  from a perspective and bottom view, in accordance with some embodiments of the inventions. 
         FIGS. 10A ,  10 B,  10 C,  10 D,  10 E, and  10 F illustrate a flowchart of the engagement of the strap pins of  FIG. 4A  with the cam spirals of  FIG. 3C  when the strap of  FIG. 1  is being driven into the cam assembly of  FIG. 1 , in accordance with some embodiments of the inventions. 
         FIGS. 11A ,  11 B,  11 C,  11 D,  11 E, and  11 F illustrate a flowchart of the engagement of the strap pins of  FIG. 4A  with the cam spirals of  FIG. 3C  when the strap of  FIG. 1  is being driven out of the cam assembly of  FIG. 1 , in accordance with some embodiments of the inventions. 
         FIG. 12  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a medical brace, in accordance with some embodiments of the inventions. 
         FIG. 13  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a pack, in accordance with some embodiments of the inventions. 
         FIG. 14  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a belt, in accordance with some embodiments of the inventions. 
         FIG. 15  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a snowboard binding, in accordance with some embodiments of the inventions. 
         FIG. 16  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a glove, in accordance with some embodiments of the inventions. 
         FIG. 17  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a sandal, in accordance with some embodiments of the inventions. 
         FIG. 18  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a shoe as a zonal closure, in accordance with some embodiments of the inventions. 
         FIG. 19  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a shoe as a powerstrap, in accordance with some embodiments of the inventions. 
         FIGS. 20A ,  20 B, and  20 C illustrate the use of a detachable strap based adjustment memory with the cam assembly and strap based closure system of  FIG. 1  on a shoe, in accordance with some embodiments of the inventions. 
         FIGS. 21A ,  21 B, and  21 C illustrate the use of a latch based adjustment memory with the cam assembly and strap based closure system of  FIG. 1  on a shoe, in accordance with some embodiments of the inventions. 
         FIG. 22  illustrates a set of components for implementing a rapid release and/or quick insertion mechanism with the cam assembly and strap based closure system of  FIG. 1  from a side view, in accordance with some embodiments of the inventions. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Numerous technical details are set forth in this description. These details are provided to illustrate some embodiments of the inventions, and are not intended to limit the inventions. Thus, nothing in this detailed description is intended to imply that any particular feature, characteristic, or component of the disclosed system is essential to the inventions. 
       FIG. 1  illustrates a set of components for implementing a cam assembly and strap based closure system using a spiral from a perspective view, in accordance with some embodiments of the inventions. As depicted in this drawing, a cam assembly  30  may comprise housing  44 , a knob  42 , a cam  40 , and a track insert  46 . The cam assembly  30  and housing  44  may be adapted to receive a strap  48 . The term “strap” is meant to define a broad term as well as its ordinary meaning. Likewise, the term “cam assembly” is meant to define a broad term as well as its ordinary meaning. The cam assembly  30  and strap  48  may be made from numerous materials including various plastics, metals, composites, polymers, and alloys. In the illustrated embodiment, the housing  44  has a track insert  46  positioned inside the housing  44 . The track insert  46  may be adapted to allow a strap  48  to move in both an inwards and outwards direction. The housing  44  has a first opening  50  and a second opening  52 , which may be configured to receive a strap  48  moving in both an inwards and outwards direction as well. In some embodiments, the track insert  46  may be integrally formed with the housing  44 . 
     As further depicted in  FIG. 1 , the cam assembly  30  has a knob  42  and a cam  40 . In some embodiments, once the cam  40  has been correctly positioned, and the knob  42  is positioned over the cam  40 , the two can be snapped together using a locking mechanism. Alternatively, the cam  40  and knob  42  may be adhered together, stitched together, divided into three or more components, be a single component, or use other attachment means. 
     The strap  48  may comprise one or more strap pins  60 . In some embodiments the strap pins  60  may be a pointed piece of wood, metal, or plastic. In some embodiments the strap pins  60  may be a short rod. In some embodiments, the strap pins  60  may be projections, teeth grooves, channels, and/or other variations and combinations. 
       FIGS. 2A ,  2 B, and  2 C illustrate the cam assembly  30  and strap  48  based closure system of  FIG. 1  from a side, top, and bottom view, in accordance with some embodiments of the inventions. As depicted in the side view of the  FIG. 2A , by rotating the knob  42  in one direction the strap  48  can be pulled into the cam assembly  30  through the first opening  50 , onto the track insert  46  (not visible from this view), through the second opening  52 , and out of the housing  44 . As further depicted in  FIG. 2A , by rotating the knob  42  in another direction the strap  48  can be pulled back through the track insert  46  (not visible from this view), through the first opening  50 , and out of the housing  44 . The strap  48  is driven through the cam assembly  30  when the strap pins  60  engage with the cam  40 . 
     As further depicted in the top view of  FIG. 2B , in some embodiments the cam  40  sits inside the knob  42 . The knob  42  may then be rotated to drive the strap  48  through the first opening  50  into the cam assembly  30 , and out the second opening  52 . 
     As depicted in the bottom view of  FIG. 2C , in some embodiments, the track insert  46  is positioned to sit inside the housing  44 . The cam  40  is then positioned to sit above the track insert  46  on top of the housing  44 . The cam may include one or more cam spirals  41  that cause the strap pins  60  on a strap  48  to be pulled through the cam assembly  30 . 
       FIGS. 3A ,  3 B,  3 C, and  3 D illustrate the cam  40  of  FIG. 1  from a top, bottom, and perspective views, in accordance with some embodiments of the inventions. As depicted in the top view of  FIG. 3A , the cam may have a crown  47  that may be placed in one or more channels or grooves on the knob  42  that are fitted to the cam  40 , and allow the cam  40  to attach to the knob  42 . In some embodiments, once the cam  40  has been correctly positioned, and the knob  42  is positioned over the cam  40 , the two are configured to be snapped together using a locking mechanism. Alternatively, the cam  40  and knob  42  may be adhered together, divided into three or more components, or be a single component. 
     As further depicted in the bottom and perspective views of  FIGS. 3B and 3C , in some embodiments, the cam  40  contains one or more cam spirals  41 . The knob  42  may then be rotated to drive the strap  48  through the first opening  50  into the cam assembly  30 , and out the second opening  52 . In some embodiments, the cam spirals  41  are in the shape of logarithmic spirals, also known as equiangular spirals. In some embodiments, other types of spirals may be used, including Archimedean spirals. In some embodiments, two, three, four, or more cam spirals  41  may be used. Increasing the number of cam spirals  41  may be used to increase the speed at which the strap  48  is inserted. This may be particularly useful for applications where the closure is large. 
     The use of cam spirals  41  may allow the strap  48  to self-lock into the cam assembly  30  at certain contact angles. Logarithmic spirals may allow the strap pins  60  on the strap  48  to be pulled at a linear velocity and constant contact angle. Different materials may also be used to vary the friction coefficients and make the system self-locking. Self-locking may allow the strap  48  to remain in the same position in the cam assembly  30  when outwards forces and/or inwards forces are applied to the cam  40  and/or strap  48 . When logarithmic cam spirals are used, a constant angle of contact may be maintained with the strap pins  60  on the strap  48 , resulting in a self-locking system that may be infinitely adjustable, and one where the torque felt by the knob  42  may be constant. However, an Archimedean spiral may be used to vary the contact angle, such as by continuously decreasing it. 
     The self-locking mechanism may be determined by the contact angle  45  and the friction applied to the circumference of the cam spirals  41  on the cam  40 . The contact angle  45  may correspond to an angle between lines tangent to a strap pin  60  and a cam spiral  41 . In some embodiments, the contact angle  45  of a self-locking mechanism may be less than approximately 20 degrees, and less than approximately 15 degrees. In some self-locking embodiments, the contact angle is between approximately 10 and approximately 12 degrees. Low contact angles may allow the cam assembly  30  to be self-locking and continually adjustable both inwards and outwards. Various contact angles can be generated depending on the speed of wind and power desired. Larger contact angles  45  may result in faster insertion speed. Other secondary frictional elements can also be added to resist the turning of the cam  40 . In some embodiments, these secondary frictional elements may be “stepless” to maintain infinite variability of position. 
       FIGS. 4A and 4B  illustrate the strap  48  of  FIG. 1  from a perspective and top view, in accordance with some embodiments of the inventions. The strap  48  comprises one or more strap pins  60 . The strap pins  60  may be in the shape of cylinders extending from the surface of the strap  48  as illustrated. In some embodiments, the strap pins  60  may be other shapes including but not limited to rivets, teeth, threads, spirals, spiral threads, slots, strips, channels, and/or grooves that may be perpendicular or at other angles to the strap  48 . In some embodiments, the cam  40  may have cam spirals  41  in complementary form and/or surfaces that may be complementary or correspond to the shape of the strap pins  60 . 
     In some embodiments, the strap  48  may have a chamfer  62  on the first strap pin closest to the cam assembly insertion end  63 , to allow the first strap pin to skip past the cam  40 . The chamfer  62  may be at a range of angles, including approximately 45 degrees. The chamfer  62  may also maintain engagement between the cam  40  and the strap  48  to ensure that they continue to function. In some embodiments, a chamfer  62  may be on other strap pins  60 , including the last strap pin furthest from the cam assembly insertion end  63  of the strap  48 . In some embodiments, a chamfer  62  may be included on the last strap pin, in addition to, or in lieu of, being on the first strap pin. 
     In some embodiments, the chamfer  62  on the last strap pin may face the opposite direction of the chamfer  62  on the other strap pins. The chamfer  62  on the last strap pin may prevent the cam spirals  41  from pulling the strap  48  further into the cam assembly  30 . In some embodiments, the chamfer  62  on the first strap pin, may keep the strap  48  from being pushed any further out of the cam assembly  30  and/or the chamfer  62  on the last strap pin may prevent the strap  48  from being pulled any further into the cam assembly  30 . 
     In some embodiments, the hard stop  67  described in greater detail below, may be used as an alternative to the chamfer  62  and/or in combination with the chamfer  62 . In some embodiments, the hard stop  67  may be located near the first strap pin and/or last strap pin. In some embodiments, the hard stop  67  may not include a hole  66  when used in conjunction with the chamfer  62  on the last strap pin. In some embodiments, this may prevent the strap  48  from compressing and entering into the cam assembly  30  regardless of the pressure applied to the strap  48 . 
     As further depicted in  FIGS. 4A and 4B , the strap  48  has a cam assembly insertion end  63  which is the end of the strap  48  that is inserted directly into the cam assembly  30 . The strap  48  may be configured to resist being completely removed from the cam assembly  30  after insertion. In some embodiments, this resistance may be provided by a hard stop  67 . In some embodiments, the hard stop  67  may be a variable stop that may be overcome given enough force. In some embodiments, the hard stop  67  may be placed near the first strap pin, the last strap pin, near other strap pins and/or multiple hard stops may be used. 
     The hard stop  67  may include a hole  66  and one or more outward projections  64 . The hole  66  may allow the outward projections  64  to compress toward the axial center line of the strap  48  to allow the strap  48  to be inserted into the housing  44  of the cam assembly  30 . Gently tapered leading edges  64   a  allow the strap  48  to enter the housing  44  with relative ease. More steeply tapered trailing edges  64   b  make it more difficult to remove the strap  48  from the housing  44 . In some embodiments, the trailing edge  64   b  may catch the strap  48  on the housing  44  to prevent the strap from falling out of the housing  44  and may leave the strap  48  in a position to be pulled back in, i.e. in a position such that the first strap pin is in a position to be engaged by the cam spirals  41  as soon as the knob  42  is rotated in the tightening direction. In some embodiments, if enough force is used to pull the strap  48  out of the housing  44  the outward projections  64  can temporarily collapse into the hole  66  and the strap  48  may be removed. 
       FIGS. 5A ,  5 B, and  5 C illustrate the track insert  46  of  FIG. 1  from a perspective, top, and side view, in accordance with some embodiments of the inventions. The track insert  46  has a tunnel  72  that pulls the strap  48  away from the cam  40  as it is passed through the tunnel  72 . In some embodiments, the track insert guides the strap  48  along and engages the strap  48  with the cam  40  along a front edge  70  but then disengages the strap on the back edge  74 . In some embodiments, the track insert  46  pulls the strap  48  away from the cam  40  so that the cam spirals  41  are engaged in a reduced number of the strap pins  60  on the strap  48  relative to the number of strap pins  60  within the housing  44 . In some embodiments, the number of strap pins  60  engaged at any given time is one or two. This guide component or bend back mechanism may be a tunnel and/or S-shape bend and/or an arc which allows the strap pins  60  to disengage the cam spirals  41  of the cam  40 . In some embodiments, the strap pins  60  are guided away from the cam spirals  41  such that fewer than all of the cam spirals  41  engage the strap pins  60  when the strap  48  extends through the housing  44 . 
     In some embodiments, the guide component pulls the strap  48  away from the cam  40  so that the strap pins  48  do not engage on the backside of the cam  40 . In some embodiments, the guide component prevents the system from locking up and/or may strengthen the system by bringing the strap in parallel to the cam  40  for maximum holding strength. In some embodiments, the load placed on the cam assembly  30  by the strap  48  may be a shear load, which places a stress parallel or tangential to the cam assembly  30 . The guide component is particularly useful in providing the lowest possible height and/or profile of the housing  44 . The guide component may also allow the strap  48  to be fed into the cam assembly  30  without catching on the cam  40 . 
       FIGS. 6A ,  6 B,  6 C, and  6 D illustrate the housing  44  of  FIG. 1  from a perspective, side, top, and bottom view, in accordance with some embodiments of the inventions. The housing  44  has a first opening  50  and a second opening  52 , which are configured to receive a strap  48  moving in both an inwards and outwards direction. In the illustrated embodiment, the housing also has a circular opening  80 , which allows the track insert  46  to be positioned inside the housing  44 . The circular opening  80  need not be in the shape of a circle, and may be in the form of other shapes including a square, oval, or triangle. In some embodiments, the cam  40  and the knob  42  may be attached to each other, using a locking mechanism, an adhesive or any other attachment mechanism or method known to those of skill in the art. The knob  42  and cam  40  are then positioned in the circular opening  80  of the housing  44 , to sit above the track insert  46  and on top of the housing  44 . The knob  42  may then be rotated to drive the strap  48  through the first opening  50 , onto the track insert  46 , and out the second opening  52  of the housing  44 . 
     As further depicted in  FIGS. 6A ,  6 B,  6 C, and  6 D, in some embodiments, the housing  44  has a bend  86  that may be an S-shape bend and/or an arc. The bend  86  may match the shape of the bend back mechanism of the track insert  46 . The bend  86  is particularly useful in providing the lowest possible height and/or profile of the housing  44 . In some embodiments, the shape of the housing  44  may be adjusted based on the application. In some embodiments, the shape of the housing  44  may be flatter or more curved than an S-shape or an arc. 
       FIG. 7  illustrates the knob  42  of  FIG. 1  from a perspective view, in accordance with some embodiments of the inventions. The knob  42  has an overmold  92  and an undermold  100 . In some embodiments, once the undermold  100  has been correctly positioned, and the overmold  92  is positioned over the undermold  100 , the two can be snapped together using a locking mechanism. Alternatively, the undermold  100  and overmold  92  may be adhered together, divided into three or more components, or be a single component. 
     As further depicted in  FIG. 7 , in some embodiments, the knob  42  has a cam opening  90 . The cam opening  90  allows the cam  40  to sit inside the knob  42 . The cam opening  90  need not be any particular shape, and may be in the form of any shape including a circle, square, oval, or triangle. Once assembled, the knob  42  may be rotated to drive the strap  48  through the first opening  50 , into the cam assembly  30 , and out the second opening  52 . 
       FIG. 8  illustrates the overmold  92  of the knob of  FIG. 7  from a bottom view, in accordance with some embodiments of the inventions. In some embodiments, the overmold  92  also has one or more overmold teeth  94 . In this embodiment, the overmold teeth  94  allow the overmold  92  and the undermold  100  to be snapped together and unitized when the undermold  100  has corresponding teeth that fit in the one or more overmold grooves or channels  96  of the overmold  92 . In some embodiments, the overmold  92  has a cam opening  90 , which may allow different designs or colors to be used. As with the other cam openings, it may be in the form of any shape including a circle, square, oval, or triangle. In some embodiments, the overmold  92  does not include the cam opening  90 . 
       FIGS. 9A and 9B  illustrate the undermold  100  of the knob  42  of  FIG. 7  from a perspective and bottom view, in accordance with some embodiments of the inventions. In some embodiments, the undermold  100  has a cam opening  90 , which allows the cam  40  to sit inside the knob  42 . As previously mentioned the cam opening  90  may be in the form of any shape including a circle, square, oval, or triangle. In some embodiments, the undermold  100  also has one or more undermold teeth  102 . In some embodiments, the undermold teeth  102  allow the undermold  100  and the overmold  92  to be snapped together and unitized when the overmold  92  has corresponding overmold teeth  94  that fit in the one or more undermold grooves or channels  108  of the undermold  100 . As described above, in some embodiments the overmold  92  may be injection molded around a pre-made undermold  100 . In some embodiments, the cam  40  and the knob  42  may be a single component; two components; three components, such as an overmold  92 , an undermold  100 , and a cam  40 ; or four or more components. 
     As further depicted in the bottom view of  FIG. 9B , the undermold  100  of the knob  42  may have one or more cam channels or grooves  106 . As previously discussed, in some embodiments, the cam channels  106  may be fitted to the shape of the crown  47  of the cam  40 , and allow the cam  40  to attach to the knob  42 . In some embodiments, once the cam  40  has been correctly positioned, and the knob  42  is positioned over the cam  40 , the two may be snapped together using a locking mechanism or interference fit. In another embodiment, the crown may be placed on the knob  42  and channels matching the shape of the knob crown on the cam  40 . Yet alternatively, the cam  40  and knob  42  may be adhered together, divided into three or more components, be a single component, or attached using other means. In some embodiments, the outer edge of some or all of the knob  42  may include friction enhancing features such as outward projections or inwards grooves to increase the traction a user&#39;s hand would have on the knob  42 . 
       FIGS. 10A ,  10 B,  10 C,  10 D,  10 E, and  10 F illustrate a flowchart of the engagement of the strap pins  60  of  FIG. 4A  with the cam spirals  41  of  FIG. 3C  when the strap  48  of  FIG. 1  is being driven into the cam assembly  30  of  FIG. 1 , in accordance with some embodiments of the inventions. Proceeding alphabetically, each figure represents the progression of the strap  48  into the cam assembly  30  over subsequent steps of time. The cam spirals  41  of the cam  40  may drive the strap  48  into the cam assembly  30 , and may engage them at a constant angle. In some embodiments, a lower contact angle may be chosen to automatically lock the strap  48  into the cam assembly  30 . Alternatively, higher contact angles may be chosen to increase the wind speed. If the cam assembly  30  is not self-locking, an external lock such as a button or lever may be incorporated to allow the user to lock the cam assembly  30  in a desired location. In some embodiments, where the cam assembly  30  is self-locking, a secondary locking mechanism is still provided to ensure the closure system remains in position when force is applied in the inwards and/or outward directions. 
       FIGS. 11A ,  11 B,  11 C,  11 D,  11 E, and  11 F illustrate a flowchart of the engagement of the strap pins  60  of  FIG. 4A  with the cam spirals  41  of  FIG. 3C  when the strap  48  of  FIG. 1  is being driven out of the cam assembly  30  of  FIG. 1 , in accordance with some embodiments of the inventions. Proceeding alphabetically, each figure represents the progression of the strap  48  out of the cam assembly  30  over subsequent steps of time. The cam spirals  41  of the cam  40  drive the strap  48  out of the cam assembly  30 , and may engage them at a constant angle. In some embodiments, a lower contact angle may be chosen to automatically lock the strap  48  into the cam assembly  30 . Alternatively, higher contact angles may be chosen to increase the wind speed. 
       FIG. 12  illustrates use of the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a medical brace  130 , in accordance with some embodiments of the inventions. In this embodiment, the cam assembly  30  is positioned on a first side  132  of the brace  130 , and the strap  48  is positioned on a second side  134  of the brace  130 . The cam assembly  30  and strap  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated, the strap  48  is driven into the cam assembly  30 , and the first side  132  and second side  134  of the brace  130  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  132  and second side  134  of the brace  130  are pulled away from each other. 
     Multiple cam assembly  30  and strap  48  based closure systems may be provided to allow customized tension to be applied on the brace  130 . As shown, three systems may be provided. In some embodiments, one, two, four or more assemblies may be provided. In addition, the cam assembly  30  and strap  48  systems disclosed herein may be used in conjunction with other known closure systems to provide the ultimate fit. For example, the article may be partially laced, velcroed, or buckled in place in addition to one or more cam assembly  30  and strap  48  based systems. Examples of such combination systems are shown in  FIG. 19-FIG .  21 . 
       FIG. 13  illustrates use of the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a pack  140 , in accordance with some embodiments of the inventions. In this embodiment, multiple cam assemblies  30  are positioned on a first side  142  of the pack  140 , and multiple straps  48  are positioned on a second side  144  of the pack  140 . The cam assemblies  30  and straps  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first side  142  and second side  144  of the pack  140  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  142  and second side  144  of the pack  140  are pulled away from each other. 
       FIG. 14  illustrates use of the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a belt  150 , in accordance with some embodiments of the inventions. In this embodiment, the cam assembly  30  is positioned on a first side  152  of the belt  150 , and the strap  48  is positioned on a second side  154  of the belt  150 . The cam assembly  30  and strap  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first side  152  and second side  154  of the belt  150  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  142  and second side  144  of the belt  150  are pulled away from each other. 
       FIG. 15  illustrates use of the cam assembly and strap based closure system of  FIG. 1  on a snowboard binding  160 , in accordance with some embodiments of the inventions. In this embodiment, the cam assembly  30  is positioned on a first side  162  of the snowboard binding  160 , and the strap  48  is positioned on a second side  164  of the snowboard binding  160 . The cam assembly  30  and strap  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first side  162  and second side  164  of the snowboard binding  160  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  162  and second side  164  of the snowboard binding  160  are pulled away from each other. 
     In an alternate embodiment the strap  48  and cam assembly  30  may be fastened to two or more objects to draw them towards and/or away from each other. In this embodiment, the cam assembly  30  is positioned on a first object and the strap  48  on a second object. The cam assembly  30  and strap  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. When the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first object and second object are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven out of the cam assembly  30 , and the first object and second object are pulled away from each other. 
       FIG. 16  illustrates use of the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a glove  170 , in accordance with some embodiments of the inventions. In this embodiment, the cam assembly  30  is positioned on a first side  172  of the glove  170 , and the strap  48  is positioned on a second side  174  of the glove  170 . The cam assembly  30  and strap  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first side  172  and second side  174  of the glove  170  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  172  and second side  174  of the glove  170  are pulled away from each other. 
       FIG. 17  illustrates use of the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a sandal  180 , in accordance with some embodiments of the inventions. In this embodiment, the cam assembly  30  is positioned on a first side  182  of the sandal  180 , and the strap  48  is positioned on a second side  184  of the sandal  180 . The cam assembly  30  and strap  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first side  182  and second side  184  of the sandal  180  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  172  and second side  174  of the sandal  180  are pulled away from each other. 
       FIG. 18  illustrates use of the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a shoe  190  as a zonal closure, in accordance with some embodiments of the inventions. In this embodiment, multiple cam assemblies  30  are positioned on a first side  192  of the shoe  190 , and multiple straps  48  are positioned on a second side  194  of the shoe  190 . The cam assemblies  30  and straps  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first side  192  and second side  194  of the shoe  190  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  192  and second side  194  of the shoe  190  are pulled away from each other. 
       FIG. 19  illustrates use of the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a shoe  200  as a powerstrap to apply additional closing force on or near the ankle of a wearer, in accordance with some embodiments of the inventions. In this embodiment, the cam assembly  30  is positioned on a first side  202  of the shoe  200 , and the strap  48  is positioned on a second side  204  of the shoe  200 . The cam assembly  30  and strap  48  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  is driven into the cam assembly  30 , and the first side  202  and second side  204  of the shoe  200  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  is driven away from the cam assembly  30 , and the first side  202  and second side  204  of the shoe  200  are pulled away from each other. 
       FIGS. 20A ,  20 B, and  20 C illustrate the use of a detachable strap based adjustment memory with the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a shoe  210 , in accordance with some embodiments of the inventions. In this embodiment, the knob  42  may be infinitely adjustable and can be left in a particular position for an ideal fit for a particular use. The cam assembly  30  may be positioned on a first side  212  of the shoe  210 . The strap attachment  216  may be positioned on a second side  214  of the shoe  210 , which may be the opposing end of the closure system. The strap attachment  216  may be a clasp, buckle, or hook that attaches to the strap  48 , and may be capable of completely detaching from the strap  48 . The cam assembly  30  and strap attachment  216  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  may be driven into the cam assembly  30 , and the first side  212  and second side  214  of the shoe  210  are brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  may be driven away from the cam assembly  30 , and the first side  212  and second side  214  of the shoe  210  are pulled away from each other. 
     In some embodiments, when the user releases the strap attachment  216  on the second side  214  of the shoe  210 , the strap  48  may be released and detached from the strap attachment  216 . The strap  48  may then be positioned in the cam  40 , and thus the adjustment or position of the strap  48  within the cam  40  may be memorized or retained. This gross movement mechanism may allow some slack to be generated for release by the strap attachment  216 , and the closure system to be a fine adjustment that can be retained for adjusting the strap  48 . The gross movement mechanism may be particularly useful, in some embodiments, for rapid release and/or quick insertion. 
       FIGS. 21A ,  21 B, and  21 C illustrate the use of a latch based adjustment memory with the cam assembly  30  and strap  48  based closure system of  FIG. 1  on a shoe  220 , in accordance with some embodiments of the inventions. In this embodiment, the knob  42  is infinitely adjustable and can be left in a particular position for an ideal fit for a particular use. The cam assembly  30  may be positioned on a first side  222  of the shoe  220 . The latch  226  may be positioned on a second side  224  of the shoe  220 , which may be the opposing end of the closure system. The latch  226  may be attached to the strap  48 , and is capable of release. The cam assembly  30  and latch  226  may be positioned on their respective sides using adhesive, stitching, and/or various other fastening devices. In some embodiments, when the knob  42  is rotated the strap  48  may be driven into the cam assembly  30 , and the first side  222  and second side  224  of the shoe  220  may be brought towards each other. When the knob  42  is rotated in an opposite direction the strap  48  may be driven away from the cam assembly  30 , and the first side  222  and second side  224  of the shoe  220  may be pushed away from each other. 
     In some embodiments, when the user releases the latch  226  on the second side  224  of the shoe  220 , the strap  48  is loosened. The strap  48  may then be positioned in the cam  40 , and thus the adjustment or position of the strap  48  within the cam  40  is memorized or retained. This gross movement mechanism may allow some slack to be generated for release by the latch  226 , and the closure system to be a fine adjustment that can be retained for adjusting the strap  48 . The gross movement mechanism may be particularly useful, in some embodiments, for rapid release and/or quick insertion. 
       FIG. 22  illustrates a set of components for implementing a rapid release and/or quick insertion mechanism with the cam assembly  30  and strap  48  based closure system of  FIG. 1  from a side view, in accordance with some embodiments of the inventions. As depicted in this drawing, a cam assembly  30  may comprise housing  44 , a knob  42 , a cam  40 , and a track insert  46 . The cam assembly  30  and housing  44  are adapted to receive a strap  48 . In the illustrated embodiment, the housing  44  has a track insert  46  positioned inside the housing  44 . The track insert  46  is adapted to allow a strap  48  to move in both in an inwards and outwards direction. 
     As further depicted in  FIG. 22 , the cam assembly  30  has a knob  42  and a cam  40 . In some embodiments, once the cam  40  has been correctly positioned, and the knob  42  is positioned over the cam  40 , the two may be snapped together using a locking mechanism. Alternatively, the cam  40  and knob  42  may be adhered together, divided into three or more components, or be a single component. The strap  48  may comprise one or more strap pins  60 . In the illustrated embodiment the strap pins  60  are beveled. The wave washer  230  and the screw  232  allow the cam  40  and cam spirals  41  to be pulled in an upwards direction to disengage the strap  48  when the knob  42  is pulled upwards. The term “wave washer” is meant to define a broad term including, for example, springs, Belleville washers and cupped spring washers as well as its ordinary meaning. In an alternative embodiment, a spring may be used instead of a wave washer  230 . When the knob is pushed downwards the cam  40  engages the strap  48  once again. In some embodiments, an elastomeric insert may be used instead to bias the cam  40  against the strap  48 . 
     In some embodiments, the system may be configured to allow rapid release and/or quick insertion of the strap  48  for faster operation. If the cam  40  is not aligned with the strap pins  60 , then once the knob  42  is turned the strap pins  60  are reengaged. This may be particularly useful to facilitate rapid release and/or quick insertion of the strap  48  for faster operation of the closure system. In addition, in some embodiments, the system may be detented so that the knob  42  and/or cam  40  can be snapped into a release position and then snapped directly downward into a position to drive the strap  48 . 
     In the illustrated embodiment, quick insertion may be achieved by beveling the drive side of the strap pins  60 , and using a wave washer  230  so that when the strap  48  is inserted the cam  40  can hop or pass over the beveled strap pins  60  when they are mated to a beveled cam spiral  41 . This may be particularly useful for allowing the closure to open slowly, but also allowing rapid advancement or insertion of the strap  48 . In some embodiments, the tension side of the strap pins  60  may be kept at approximately 90 degrees for maximum strength and retention. 
     In an alternate embodiment, the drive side of the strap pins  60  and cam spirals  41  may be beveled. This may be particularly useful for managing the forces applied to the system for strength and safety. For example, the knob  42  and cam  40  could pop upwards and release the strap  48  to prevent overloading of the system at a predetermined load. This is particularly useful in, for example, helmet or headwear applications. 
     Although these inventions have been described in terms of certain embodiments and applications, other embodiments and applications that are apparent to those of ordinary skill in the art, including embodiments which do not provide all of the features and advantages set forth herein, are also within the scope of these inventions.