Abstract:
An improved retention mechanism for a bicycle helmet is provided. A helmet including a retention mechanism comprises a shell for protecting a head of a person and a fit system elastically coupled to the shell. The fit system comprises a bowl designed to fit an occipital region of the person&#39;s head and a hinge for coupling the fit system to the shell, the hinge permitting the fit system to move. The fit system further including a spring element for positioning the bowl against the occipital region of the person&#39;s head, to stabilize the helmet against the person&#39;s head.

Description:
RELATED APPLICATIONS 
     This application is a continuation of Assignee&#39;s application Ser. No. 09/525,997, filed Mar. 15, 2000, titled AN IMPROVED RETENTION MECHANISM FOR A HELMET now U.S. Pat. No. 6,226,802. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to helmets, and more specifically, to retention mechanisms for helmets. 
     BACKGROUND 
     Helmets for head protection during bicycle riding falls and accidents have continuously evolved and undergone numerous improvements in recent years. One particular area of refinement has been in the retention mechanism to fit and stabilize the helmet on the bicycle rider&#39;s head. An example of a prior art bicycle helmet and a means for securing it from excessive movement is disclosed in U.S. Pat. No. 5,659,900. 
     In order to fit a people having different head shapes and sizes, helmets are often available in several sizes. The fit is customized to the rider&#39;s head by inserting or removing cushions and pads around the interior of the helmet. 
     Generally prior art helmets have not been shaped to fit the curvature beneath the occipital region of the rider&#39;s head to stabilize the helmet. One prior art solution that fits the curvature beneath the occipital region of the rider&#39;s head is disclosed in U.S. Pat. No. 5,659,900. In this prior art helmet, an inverted T-shaped articulated member was attached to a back portion of the bicycle helmet shell assembly. The articulated member has a lower distal end. An elastic means connects the T-shaped articulated member and opposite sides of the shell assembly for allowing the distal end of the articulated member to extend rearward when the helmet is donned to provide a resilient forward pressure against an inwardly curved portion on the posterior of a rider&#39;s head. 
     SUMMARY OF THE INVENTION 
     A retention mechanism for a helmet is described. A helmet including a retention mechanism comprises a shell for protecting a head of a person and a fit system elastically coupled to the shell. The fit system comprises a bowl designed to fit an occipital region of the person&#39;s head and a hinge for coupling the fit system to the shell, the hinge permitting the fit system to move. The fit system further including a spring element for positioning the bowl against the occipital region of the person&#39;s head, to stabilize the helmet against the person&#39;s head. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which: 
     FIG. 1 is a side view of a wearer wearing a helmet including one embodiment of the retention mechanism according to the present invention. 
     FIG. 2 is a perspective view of one embodiment of the retention mechanism. 
     FIG. 3 is a front view of one embodiment of the retention mechanism. 
     FIG. 4A is a view of one embodiment of the screw mechanism for the retention mechanism. 
     FIG. 4B illustrates a bottom view of the helmet including the retention mechanism. 
     FIG. 5A is one embodiment of an alternative retention mechanism. 
     FIG. 5B is yet another embodiment of an alternative retention mechanism. 
     FIG. 6 is a cut-away view of one embodiment of the back of a helmet including one embodiment of the retention mechanism. 
    
    
     DETAILED DESCRIPTION 
     An improved retention mechanism for a helmet is described. The retention mechanism provides an intuitive wearer interface, permitting tension adjustment while the helmet is worn. A single knob adjustment mechanism provides two-finger adjustment, for one embodiment. The helmet including the retention mechanism covers less head surface, providing maximum heat dissipation. The retention mechanism is relatively light-weight, and provides excellent support for the helmet. For one embodiment, the universal bowl shape of the retention mechanism fits most head shapes and sizes comfortably. For one embodiment, lower strap slots keep helmet straps from becoming tangled. In this way, the new retention mechanism, described in more detail below, provides many benefits to the wearer as well as to the manufacturer of the retention mechanism and helmet. 
     FIG. 1 is a side view of a wearer wearing a helmet including one embodiment of the retention mechanism according to the present invention. FIG. 1 illustrates a side view of a helmet including the retention mechanism according to the present invention. The helmet  110  is designed to fit on the head of a wearer. The helmet  110  includes a retention mechanism  120 , which is designed to fit on the back of the helmet  110 . 
     The retention mechanism  120  attaches into the foam on the helmet  110 . The retention mechanism  120  includes an adjustment mechanism  130 , which permits a wearer to tighten or loosen the retention mechanism  120 , while the helmet  110  is on the wearer&#39;s head. The retention mechanism  120  includes a bowl shaped portion  150 , which is designed to fit the back of the head of the wearer. 
     The helmet  110  further includes a helmet strap  140 . The helmet strap  140  is attached to the helmet  110  at the front, and to the retention mechanism  120  in the back. For one embodiment, the helmet strap  140  is threaded through the bowl shaped portion  150  of the of the retention mechanism  120 , and is coupled to the back of the helmet  110 . For one embodiment, this keeps the helmet straps  140  from becoming tangled. 
     The retention mechanism  120  and the helmet strap  140  together fix the helmet  110  to the wearer&#39;s head, such that the helmet should not slip. Because of the configuration of the bowl  150 , sufficient airflow is provided to the wearer&#39;s head, to minimize discomfort. 
     FIG. 2 is a perspective view of one embodiment of the retention mechanism. The retention mechanism  120  includes a spine  250  that is designed to be attached to the helmet (not shown). The spine  250 , for one embodiment is nylon. Alternatively, the spine  250  may be any other rigid material that provides sufficient support for the bowl  210 . 
     A moving element  230  is coupled to the spine  250  by a hinge (not shown). For one embodiment, the moving element  230  and the hinge are nylon, to provide rigidity and support. Alternative materials may be used. A light-weight but rigid material is preferred. The moving element  230  is designed to hingedly move the bowl  210  between various positions. As described below, the elastic elements  290  tension the moving element  230 , such that movement of the hinge is made easier and/or harder, depending on the tension provided by the elastic elements  290 . 
     The retention mechanism  120  has a bowl  210  designed to fit the head of a wearer. For one embodiment, the bowl  210  is nylon, or another relatively rigid and easily formed material. The shape of the bowl  210  is designed to fit a variety of head shapes. For one embodiment, the bowl  210  includes a plurality of slots  220 . For one embodiment, at least one of the slots  220  is designed to have a helmet strap (not shown) threaded through the slot  220 . 
     The retention mechanism  120  includes adjustment mechanism  130 . For one embodiment, the adjustment mechanism  130  is a knob. In an alternative embodiment, the adjustment mechanism  130  may be another shape designed to be grasped by a wearer. For one embodiment, the adjustment mechanism  130  is made of thermoplastic polyurethane. Alternatively, the adjustment mechanism may be made of other materials—such as other plastics, rubbers, or metals—that are relatively rigid, and are not slippery, providing a grip for the wearer to adjust the knob. 
     The adjustment mechanism  130  is designed to control an adjustor  260 . The adjustor  260  is a screw, for one embodiment. The adjustor  260  is controlled by the adjustment mechanism  130 . For another embodiment, the adjustor  260  may be a ratchet, a pulling mechanism with multiple stops. For yet another embodiment, the adjustor  260  may be a slot/groove configuration, or any other mechanism that can adjust the elastic materials  290  providing tension in the retention mechanism  120 . For one embodiment, if the adjustor  260  is a screw, a holder  280  fixes the screw  260  in place, such that when the screw  260  is turned, the adjustment mechanism  130  does not move vertically, but the elastic materials  290  move vertically. 
     The elastic materials  290  tension the retention mechanism  120  against the wearer&#39;s head. For one embodiment, the elastic materials  290  are springs. For another embodiment, the elastic materials may be rubber, or any other material that can provide adjustable elasticity. 
     FIG. 3 is a front view of one embodiment of the retention mechanism. The spine  380  is rigid, and defines the center of the retention mechanism. The spine  380  attaches the retention mechanism  120  to the helmet (not shown). 
     Elastic elements  350  are attached to the spine on one side, and to the nut  370  on the other side. The nut  370  is moved by the screw  340 , such that when a wearer uses the knob  130  to tighten the screw  340 , the elastic elements  350  are stretched, providing more resistance to the hinge (not shown). 
     For one embodiment, the screw  340  includes a ratchet  320  at its base, such that the screw  340  does not release, except if a wearer turns the knob  130 . 
     The bowl  360  is shaped with multiple holes, for airflow. The shape of the bowl  360 , for one embodiment, is optimized to fit multiple head shapes and head sizes. The bowl, for one embodiment, may include reflector decals  310  for additional safety, and to identify the retention mechanism  120 . 
     FIG. 4 is a view of one embodiment of the spine, adjustor, and adjustment mechanism for the retention mechanism. The spine  430  is shaped to receive a screw  460  that is used to attach the retention mechanism to the helmet. For one embodiment, the screw  460  is attached through a washer  465 , which is shaped to fit the top of the helmet (not shown). For one embodiment, a coverlet  470  is designed to fit over the washer  465 . For one embodiment, the coverlet  470  is designed such that it does not interrupt the airflow over the helmet. For one embodiment, the coverlet  470  is designed of the same material as the cover of the helmet. For one embodiment, the helmet is made of foam, and covered with a plastic material. For one embodiment, the coverlet  470  is made of the same type of plastic material. 
     For one embodiment, the screw  460  may be screwed into the helmet at multiple angles. In this way, the angle of the spine, and thus the retention mechanism, may be adjusted. For one embodiment, this adjustment may be done by the wearer. 
     The spine  430  includes a hinge  435 , designed to receive the bowl (not shown). The side of the spine  420  is shaped to follow the contour of the bowl. 
     For one embodiment, the screw  440  is designed to turn to tighten the elastic elements (not shown). For one embodiment, the screw  440  is fixed such that it does not extend further from the spine, when it is turned. 
     The spine may further include a tooth  455 , designed to further secure the retention mechanism into the helmet. The tooth  455 , for one embodiment, extends the same length as the wings. FIG. 4B illustrates a bottom view of the helmet including the retention mechanism. As can be seen, the teeth  455  are secured directly into the foam  495  of the bottom  490  of the helmet. FIG. 
     FIG. 5A is one embodiment of an alternative retention mechanism. The spine  510  supports the retention mechanism, and is used to attach the retention mechanism to a helmet (not shown). For one embodiment, the spine includes a location for a screw at its top, and a location for a hook or similar device at its bottom, to firmly attach the retention mechanism  120  to the helmet. 
     The retention mechanism  120  further includes an elastic element  515 , adjusted by adjustment element  520 . For one embodiment, the elastic element  515  is a rubber or similar material, with a relatively high elasticity and adjustable resistance. The wearer can pull on adjustment element  520 , which is a finger-grip for one embodiment. By setting the elastic element  515  at different extensions, the resistance provided by the elastic element is increased. The elastic element  515  is coupled to the hinge (not shown) at the top  540 , such that as the resistance provided by the elastic element is increased, the ease of movement of the hinge is lowered. This provides stronger or weaker support for the wearer, based on the wearer&#39;s adjustment. 
     The retention mechanism  520  further includes a bowl  530 . For one embodiment, the bowl  530  includes a plurality of cut-outs. The cut-outs are shaped to maximize airflow over the wearer&#39;s head, yet provide enough support to stabilize the helmet. Furthermore, the bowl  530  must have sufficient rigidity, even including the cut-outs, to provide stable support. 
     FIG. 5B is another embodiment of an alternative retention mechanism. The spine  550  is designed to be attached to the helmet (not shown) at the top, as well as at the bottom. For one embodiment, teeth  555  are designed to grip into the foam of the helmet when the retention mechanism  120  is in the helmet. 
     The retention mechanism  120  includes elastic elements  560  which provide resistance to hinge  565 . The hinge  565  is coupled to a bowl  570 . The bowl is designed to fit the back of a wearer&#39;s head. The elastic element  560  provides a steady resistance, permitting a wearer to place the helmet on his or her head, but forcing the bowl  570  against the wearer&#39;s head. The bowl  570  may include a cut-out  575 , to improve airflow over the wearer&#39;s head. The configuration of the cut-out  575  is arbitrary, but is generally designed to optimize airflow while providing stability to the bowl  570 , and thus to the retention mechanism on the wearer&#39;s head. 
     FIG. 6 is a cut-away view of one embodiment of the back of a helmet including one embodiment of the retention mechanism. The retention mechanism  120  is fastened to the helmet by a screw  625  and a molded washer  620 . The molded washer  620  is designed to fit into the helmet. For one embodiment, the molded washer  620  is shaped to fit into a hole in the helmet, such that the aerodynamic qualities of the helmet are not changed. 
     The retention mechanism  120  further includes an adjustment device  650 , to change the tension of the retention device. The adjustment device  650  is controlled by knob  640 . For one embodiment, a tooth  670  further attaches the retention device  120  into the helmet  610 . 
     FIGS. 1-6 have shown various elastic element configurations, some of which were configurable while others were non-configurable and provide a steady resistance. It is to be understood that alternative elastic elements may be used. The elastic elements may be adjustable in various ways, including a screw, a ratchet, an elastic band, or other adjusting means. The elastic elements may be non-adjustable, in the alternative. It is to be understood that other types of elastic elements may be used to provide resistance of the bowl against a wearer&#39;s head. 
     The configuration of the cut-outs in the bowl may be varied as well. For one embodiment, no cut-outs may be. present, small cut-outs may be present, or various configurations of larger and/or smaller cut-outs may be present. 
     In the foregoing specification, the invention has been described with reference to specific exemplary embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.