Abstract:
A head and neck support and restraint system including protective headwear worn by a user; an article worn about the shoulders, chest and back of the user; and a dynamic connector that is disposed between and attached to the protective headwear and the worn article that dampens and distributes forces to which the head and neck are subjected during use. Such forces can include forces experienced as a result of acceleration, deceleration, or impact during a collision between the user and another person or object. The dynamic connector also supports and limits the rate and range of motion permitted between the head and neck relative to the shoulders, chest and back of a user when the head or body of the user is subjected to such forces.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Patent Application No. 62/115,281, filed Feb. 12, 2015. 
    
    
     TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a system and apparatus useful for supporting and protecting the head (including without limitation the face, skull and brain) and neck of a user by damping and distributing forces to which they would otherwise be subjected during sudden acceleration, deceleration or impact. Such forces can arise, for example, during a collision between the user and an animate or inanimate object, no matter whether accidental or intentional. 
     2. Description of Related Art 
     In recent years much attention has been drawn to the causes and effects of head, neck and brain injuries due to concussive forces experienced by persons engaged in activities such as, for example and without limitation: football; baseball; soccer; hockey; lacrosse; boxing; bull riding; skiing; snowboarding; skateboarding; sky-diving; base jumping; bicycling; motorcycling; riding all-terrain vehicles; car or boat racing; piloting aircraft; performing military, law-enforcement or fire-fighting operations or maneuvers; other vehicular maneuvers, fire-fighting, and the like. Historically, efforts to lessen the risk or likelihood of serious physiological injury when engaging in such activities have focused on providing a helmet or other headwear comprising one or more of an outer shell or cover in combination with cushioning pads, collapsible layers, or other impact-absorbing structures or materials intended to protect the head of the user from impact or injury. 
     Despite the improvements to headwear that have been made in recent years, such devices or apparatus are still typically configured in such manner that the neck is required to support the weight of both the head and the protective headwear, sometimes supplemented by neck cushions or collars disposed or worn between the head and shoulders of the user. Because the weight of the prior art protective headwear is supported primarily by the neck of the user, designers are further constrained in the design of headwear by the need to make the headwear relatively lightweight or risk further physiological damage or injury due to the combined weight of the head and headwear. Also, conventional protective headwear typically does not limit either the rate or range of motion of the head or neck relative to other parts of the body when subjected to acceleration, deceleration or impact. 
     A system and apparatus are needed that will support the head and neck, and supplement the protective features of conventional headwear by dampening and dissipating forces otherwise applied to the head and neck during a collision or impact; by distributing the dissipated forces to the shoulders, chest and back of a user without passing through and risking injury to the neck and cervical vertebrae; and by limiting the rate and range of motion permitted to the head and neck relative to the shoulders, chest and back of a user. 
     SUMMARY OF THE INVENTION 
     The subject system and apparatus are useful for avoiding or limiting physiological and neurological damage or injury when the user engages in or performs activities that are vocational, avocational or recreational without regard to whether such collisions are intentional or accidental in nature. The subject system and apparatus will support head and neck of a user and desirably permit rotational, tilting and stretching movement of the head and neck of a during normal or routine performance of the movements needed for engaging in a particular activity. However, when the head and neck of the user are subjected to an extraordinary impact or forces that may cause physiological injury to the user, the subject system and apparatus will desirably limit the rate and ranges of rotation, tilt, and compression or elongation of the head and neck relative to the chest, back and shoulders of a user when the head or body of the user. 
     The system and apparatus of the invention will desirably respond in real time as the impact or other forces are inflicted upon the user, thereby arresting movement of the head and neck within predetermined allowable limits and also damping the forces and distributing the damped forces throughout the body before physiological damage occurs. When .the forces are distributed or dissipated, the system and apparatus return to the original configuration, allowing routine movement as required for performance of the activity for which they are designed. 
     In one embodiment of the invention, a head and neck support and restraint system is disclosed that comprises protective headwear worn by a user of the system; an article worn about the shoulders, chest and back of the user (the “worn article”); and a dynamic connector disposed between and attached to the protective headwear and the worn article that supports the head and neck and dampens and distributes forces to which the head and neck of the user are subjected during use. Such forces can include forces experienced as a result of acceleration, deceleration, or impact during a collision between the user and another person or object during use. The dynamic connector will also desirably limit the rate and range of motion permitted between the head and neck relative to the shoulders, chest and back of a user when the head or body of the user is subjected to such forces. 
     In one embodiment, the subject apparatus includes a dynamic connector that desirably comprises a first end attachable to protective headwear of a user; a second end attachable to an article worn about the shoulders, chest and back of a user; and at least one rotation damper, at least one tilt damper and at least one elongation and compression damper disposed between the first and second end. In one embodiment of the invention, an elongate shaft also desirably extends between the first and second ends and passes through the at least one rotation damper, the at least one tilt damper, and the at least one elongation and compression damper. In another embodiment of the invention, the elongate shaft has a first portion that is flexible and a second portion that is relatively inflexible. The flexible portion desirably passes through the at least one rotation damper and the at least one tilt damper, and the relatively inflexible portion passes through the elongation-compression damper. One end of the flexible shaft is desirably coupled to an adjacent end of the inflexible shaft so that elongation or compression forces applied to the dynamic connector can be transmitted through the flexible and inflexible shafts to the elongation-compression damper of the dynamic connector. 
     The flexible shaft desirably comprises a cross-section that embodies one or more keys adapted for insertion into cooperatively aligned bores of the damping devices, some portions of which can have cooperatively configured keyways to facilitate rotational engagement at least between the flexible shaft and those portions of the rotational damper through which rotational forces imparted to the dynamic connector are communicated to facilitate damping and provide constraints as to the rate and range of permitted motion as discussed in greater detail below. The flexible shaft can be made by conventional means from any durable material, which can include for example a polymeric material that is generally suitable for such purposes, with a coefficient of elasticity, coefficient of elongation, flex modulus, glass transition temperature, impact resistance and service life that are consistent with the intended use and use environment. 
     If desired, at least one removable release mechanism such as a release pin is optionally provided for use in quickly and selectively detaching the subject apparatus from either or both of the protective headwear and the article worn by the user. If desired, a removable locking key is optionally provided that is engageable with the dynamic connector for use in selectively locking all major components of the apparatus into a fixed position relative to each other if, for example, it becomes desirable during an emergency situation to immobilize the head relative to the body of the wearer. 
     In one embodiment of the invention, a rotation damper is disclosed for use in the dynamic connector that further comprises a variable-response fluid damping valve in which two opposed internal paddles move through cooperatively configured fluid chambers containing a viscous fluid, displacing fluid from one chamber to another through at least one fluid passageway disposed in fluid communication with the two chambers. As used in relation to this embodiment of the invention, “variable response” refers to the resistance applied to flow of the viscous fluid inside the rotation damper by reason of the restricted cross-sectional area of the fluid passageway and the viscosity and incompressibility of the fluid. 
     In one embodiment of the invention, a variable response tilt damper is disclosed that desirably comprises at least one, and preferably a plurality of circumferentially spaced, interconnected flexible pouches disposed between two opposed discs, with each pouch containing a quantity of viscous fluid. When a portion of one disc is pressed closer to the other by flexure of a flexible shaft passing through the tilt damper, the viscous fluid disposed in the flexible pouch adjacent the area in which the closer movement occurs desirably offers increasing resistance to the tilt that is dependent upon factors such as the elasticity of the pouch material and the volume of fluid inside the pouch relative to the internal volume of the pouch. The ability of an individual pouch to distend into another area between the opposed discs is desirably limited by a support frame that defines boundary limits within which each pouch is confined during use of the apparatus. As used in relation to this embodiment of the invention, “variable response” refers to progressively greater resistance to tilting of one disc relative to the other due to the confinement and incompressible nature of the viscous fluid. 
     In one embodiment of the invention, an elongation and compression damper is disclosed that comprises a variable-response, double-acting piston and cylinder in which a piston reciprocates to force a viscous fluid back and forth between two cylinder chambers disposed on opposite sides of the piston through at least one fluid passageway in the piston that is in fluid communication with each of the two oppositely disposed chambers. The maximum elongation or compression of the dynamic connector is limited to the stroke length of the piston. The piston shaft is desirably inflexible and is coupled to an end of a flexible shaft portion that passes through at least one of a rotation damper and a tilt damper of the dynamic connector. As used in relation to this embodiment of the invention, “variable response” refers to the resistance applied to flow of the viscous fluid inside the elongation and compression damper by reason of the restricted cross-sectional area of the at least one fluid passageway through the piston and the viscosity and incompressibility of the viscous fluid disposed inside the two oppositely disposed cylinder chambers. 
     A satisfactory viscous fluid for use in at least some embodiments of the invention is a medium weight oily fluid that does not degrade or have any significant detrimental reaction with the materials from which the internal components of the rotation damper, tilt damper and elongation-compression damper of the apparatus of the invention are made. 
     In one embodiment of the invention, the dynamic connector disposed between and attached to the protective headwear and the worn article transmits the dampened forces originally received from the protective headwear through the point of attachment to the worn article, which then distributes those forces throughout the worn article in a method consistent with its physical configuration and the materials from which is it constructed to the shoulders, chest and back (collectively, “trunk,” or “body” when differentiated from the head and neck) of the user, and through the skeleton and musculature of the user to the legs, feet and underlying support surface upon which the user is standing or resting. Depending upon the activity in which the user is engaged, the worn article may take on various physical configurations such as, for example, shoulder pads, a vest, pack, pack frame, reinforced jacket, or the like. The addition of a belt disposed around the waist can also distribute some forces directly to the pelvis and hips of the user, further lessening forces to be absorbed by the spine during use. In one embodiment of the invention, a force indicator is also included in the subject head and neck restraint system to alert users or medical personnel if the design limits of the system were exceeded by the concussive force to which the user was subjected. 
     Satisfactory devices for use in attaching the dynamic connector to protective headwear or to a worn article can include any known device or assembly capable of withstanding the forces expected to be encountered during use of the invention. Similarly, although satisfactory embodiments of the system and apparatus of the invention are disclosed here, other embodiments of the invention utilizing other similarly effective means for achieving the functional objectives disclosed here will become more apparent to those of ordinary skill in the art who have read this disclosure in view of the accompanying drawings, and it should be understood that the subject invention is not limited to the particular mechanical design disclosed in the accompanying detailed description of one embodiment. 
     These and other features and advantages of the present invention will become better understood from a consideration of the following detailed description of the preferred embodiments and appended claims in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The system and apparatus of the invention are further described and explained in relation to the following drawings wherein: 
         FIG. 1  is a simplified rear elevation view of one embodiment of the system of the invention; 
         FIG. 2  is a side elevation view of the embodiment of  FIG. 1 ; 
         FIG. 3  is an enlarged rear elevation view of the dynamic connector of the embodiment of  FIG. 1 ; 
         FIG. 4  is an enlarged plan view of the dynamic connector of  FIG. 3  with the top cover removed; 
         FIG. 5  is a cross-sectional elevation view, partially broken away, taken along line  5 - 5  of  FIG. 4 ; 
         FIG. 6  is a plan view of a plurality of tilt dampers of the invention as viewed along line  6 - 6  of  FIG. 7 ; 
         FIG. 7  is a simplified cross-sectional elevation view of a plurality of tilt dampers installed on a flexible shaft as viewed along line  7 - 7  of  FIG. 6  but not showing the internal configuration of tilt dampers  46 ; 
         FIG. 8  is an enlarged cross-sectional elevation view of the lower portion of the dynamic connector of the embodiment of  FIG. 1  as viewed along line  8 - 8  of  FIG. 3 ; 
         FIG. 9  is a cross-sectional elevation view of an assembled rotation damper; 
         FIG. 10  is a cross-sectional elevation view of the cap of the rotation damper of  FIG. 9  as taken along line  10 - 10  of  FIG. 11 ; 
         FIG. 11  is a bottom plan view of the cap portion of the rotation damper of  FIG. 10 ; 
         FIG. 12  is a cross-sectional elevation view of the base of the rotation damper of  FIG. 9  as viewed along line  12 - 12  of  FIG. 13 ; 
         FIG. 13  is a plan view of the base of the rotation damper of  FIG. 9 ; 
         FIG. 14  is a cross-sectional elevation view of an assembled tilt damper as viewed along line  14 - 14  of  FIG. 16 ; 
         FIG. 15  is a bottom plan view of the cap of  FIG. 14 ; 
         FIG. 16  is a cross-sectional plan view taken along line  16 - 16  of  FIG. 14 ; 
         FIG. 17  is a cross-sectional elevation view of the base of  FIG. 14  as viewed along line  17 - 17  of  FIG. 18 ; 
         FIG. 18  is a plan view of the base of  FIG. 14 ; 
         FIG. 19  is a simplified cross-sectional elevation view of the pouch ring of the tilt damper of  FIG. 14  taken along line  19 - 19  of  FIG. 20 ; and 
         FIG. 20  is a plan view of the pouch ring of the tilt damper of  FIG. 14 . The drawings are not to scale and the relative proportionality and scale of like-numbered elements sometimes varies in different Figures of the drawings. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIGS. 1-2 , a representative satisfactory embodiment of the subject head and neck support and restraint system  10  of the invention comprises football helmet  22  and shoulder pads  24  that can be releasably interconnected by dynamic connector  20 . It should be understood, however, that football helmet  22  and shoulder pads  24  are merely illustrative of the many other types and varieties of protective headwear and articles such as vests, jackets, harnesses (collectively, “body wraps”) that can be worn by a user and that can be assembled using a dynamic connector  20  to configure a satisfactory embodiment of the head and neck support and restraint system  10  of the invention. Such protective headwear and body wraps can be constructed using a wide variety of polymeric, metallic materials and fabric materials known by those of ordinary skill in the art to be suitable for use in such applications. 
     Of particular interest in relation to the embodiment of the invention depicted in  FIGS. 1 and 2 , the top end of dynamic connector  20  plugs into a socket  12  (best seen in  FIG. 2 ) that is molded or otherwise provided in the back of helmet  22  to facilitate releasable attachment of the two. Also, it will be observed upon reading this disclosure that bracket  26  is provided for the releasable attachment of dynamic connector  20  to shoulder pads  24 . Although conventional football shoulder pads rest on the shoulders of the user, they are “worn” by the user in the sense that they are often laced in front around the upper chest of the user, and thereby also constitute a “body wrap” that constricts around the back and trunk portion of the body of the user. Many conventional attachment systems and devices are available that can be readily used or modified for use with particular headwear and body wraps. 
     Desirably, head and neck support and restraint system  10  of the invention can be designed, fabricated and tailored to a particular activity and user demographic so that it will not be burdensome to wear when a user is participating in normal, routine performance of an activity where there is some risk of being subjected occasionally to a concussive force but where the user is more often interested in being able to move relatively freely and without undue constriction. For activities involving higher risk of physiological injury due to concussive forces, the subject invention will understandably be configured to be more durable and may provide somewhat greater limitations to a user&#39;s ability to move naturally while wearing the apparatus. Because the weight of helmet  22  is primarily supported by dynamic connector  20 , the combined weight of the head and helmet are not supported by the neck as with conventional protective headwear, and helmet  22  does not contribute to the dynamic load transmitted to and through the neck either during normal use or when helmet  22  is subjected to a concussive force. 
     Referring to  FIGS. 1-3 , dynamic connector  20  is desirably attached to helmet  22  and shoulder pads  24  by a spring-loaded, quick-release connector pin  14  ( FIG. 2 ) and connector bracket  26  ( FIG. 1 ), respectively. Referring to  FIG. 3 , dynamic connector  20  desirably further comprises at least one, and preferably two or more rotation dampers  40 . In the embodiment shown, rotation dampers  40  are spaced apart near the upper and lower ends of dynamic connector  20 , with a plurality of tilt dampers  46  disposed between them. Flexible shaft  42  extends through the coaxially aligned rotation dampers  40  and tilt dampers  46  to facilitate tilting movement of helmet  22  in relation to the longitudinal axis through the center of elongation-compression damper  50 . 
     As used in this disclosure in relation to the presently described embodiment of the invention, “tilt” and “tilting” should be understood to include movement of the head and neck of the user in any direction away from a longitudinal axis through the center of the coaxially aligned elements of elongation-compression damper  50  of dynamic connector  20 . When dynamic connector  20  is vertically disposed as shown in  FIG. 2 , “tilt” or “tilting” refers to movement of helmet  22  in a direction that tips or leans forward, backward, left, right, or in any other intermediate direction from the longitudinal axis through elongation-compression damper  50  ( FIG. 3 ). When dynamic connector  20  is horizontally disposed, as might occur for example when the upper body of a football player is parallel to the ground, “tilt” or “tilting” is still movement of helmet  20  in any direction away from the longitudinal axis through elongation-compression damper  50 . “Tilting” is distinguished from “rotation” of helmet  22  relative to shoulder pads  24  in that “rotation” refers to movement of helmet  22  around the longitudinal axis. 
     Elongation-compression damper  50  of dynamic connector  20  controls and limits the rate and range of response when dynamic connector  20  is subjected to elongation or compression due to concussive forces imparted to helmet  22 . Elongation-compression damper  50  is useful in damping concussive forces that are imparted to helmet  20  from any direction having a component force vector along the longitudinal axis through the device. A significant advantage of the present invention is that the rotation dampers  40 , tilt dampers  46 , and elongation-compression damper  50  of dynamic connector  20  are configured so as to limit both the rate and range of travel of helmet  22  relative to shoulder pads  24  when subjected to a high intensity concussive force. The structure and operation of one embodiment of each of rotation dampers  40 , tilt dampers  46  and elongation-compression damper  50  are further described and explained in relation to  FIGS. 6-20  below. 
     Referring to  FIGS. 3-5 , helmet mount fixture  30  is desirably configured to slidably engage and be releasably attachable to helmet  22 . Base  38  of helmet mount fixture  30  is seated at the top of upper rotating damper  40  and contains a longitudinal bore through which flexible shaft  37  is insertable, passing downwardly sequentially through upper rotating damper  40 , a plurality of tilt dampers  46 , lower rotating damper  40 , and impact force indicator disc  45  ( FIG. 3 ). Although impact force indicator disc  45  is depicted here as being disposed between the lowest tilt damper  46  and the lower of two rotation dampers  40 , it can similarly be positioned anywhere along the stem of dynamic connector  20  for use in the invention. Impact force indicator disc  45  can be made satisfactorily using metallic or polymeric materials appropriate to the intended use, or a combination thereof, and desirably includes one or more sensors that sense and transmit real-time impact data wirelessly to a receiver and recorder. 
     Flexible shaft  37  is desirably constructed of a durable, extrudable polymeric material that will flex but not fracture when subjected to the range of torsional, flexural, tensile and compression loadings likely to be encountered during use. Flexible shaft  37  desirably has a non-circular cross-section that is engageable with an inwardly facing collar inside each rotation damper  46  as flexible shaft  37  is inserted through the aligned longitudinal bores of the constituent elements of dynamic connector  20 . A cylindrical packing  42  or functionally equivalent sealant layer is desirably provided where flexible shaft  37  passes through fluid-containing rotating dampers  40  and tilt dampers  46 . The upper end of flexible shaft  37  is desirably connected to helmet mounting fixture  30  by one or more pins  32 ,  34 ,  39 , with one or both of pins  32 ,  34  also being available for use in attaching helmet mounting fixture  30  to helmet  22 . If desired, a locking key can also be provided to enable medical personnel to secure and immobilize helmet  22  and the head and neck of a user in an optimal position to allow transport of the user without movement of the head and neck relative to the shoulders following a concussion or other injury. Such a locking key is desirably insertable through a longitudinally extending keyway that can be internal to and coaxially aligned with, or offset from, flexible shaft  37 . 
     Referring to the embodiment of the present invention that is shown in  FIGS. 3 and 8 , elongation-compression damper  50  is disposed at the base of dynamic connector  20 . An elongation-compression damper  50  that is satisfactory for use in the invention comprises a mounting disk and coupling  68  near the uppermost end that attaches the lower end of flexible shaft  37  to the upper end of piston rod  48 . Piston rod  48  is in turn coupled in fixed relation to piston  56 , which further comprises at least one fluid passageway  58 . Piston  56  is desirably a double-acting piston disposed inside cylinder  60 , which also contains a predetermined volume of an oily or oil-like fluid  64  that does not completely fill the voids inside cylinder  60  and fluid passageway(s)  58 . Fluid seal  56  is desirably disposed above cylinder  62 , and is maintained by keeper rings  52 ,  54 . 
     Elongation-compression damper  50  is configured to damp forces imparted to dynamic connector  20  that have component forces acting in the longitudinal direction that act either to elongate or compress the connector. In the absence of the invention, a significant portion of an impact received on the crown of an item of protective headwear is transmitted through the cervical vertebrae to the spine. One purpose and intended function of dynamic connector  20  and, more particularly, of elongation-compression damper  50  is to take that load away from the neck and reduce the magnitude of the force before distributing it to the body through a worn article to which the lower end of dynamic connector  20  is attached. The force is dissipated by using a significant portion of the energy applied through piston rod  48  to drive double-acting piston  56  inside cylinder  60  while simultaneously displacing fluid  64 , preferably a medium viscosity oil, through one or more fluid passageways  58  in piston  56  to the other side of cylinder  60 . The maximum range of travel of piston rod  48  is determined by the overall length of cylinder  60  less the thickness of piston  56 . 
     Referring to  FIGS. 9-13 , each rotation damper  40  preferably further comprises cap  70  and base  72 , each of which has a circular shape, with the outside diameter of cap  70  being slightly greater than the outside diameter of base  72  to facilitated fluid-tight slip-fit engagement between them. In the depicted embodiment, cap  70  comprises annular recess  78  into which annular rim  80  can slide into engagement when assembled as shown in  FIG. 9 . Both cap  70  and base  72  also have centrally disposed longitudinal bores  74 ,  76 , with the bore of cap  70  being smaller than that through base  72 . As seen in  FIG. 11 , bore  74  of cap  70  is configured in size and shape to receive flexible shaft  37  ( FIG. 3 ) into slidable engagement with it, while bore  76  of base  72  is large enough to permit shaft  37  to spin inside it when cap  70  and base  72  are assembled as shown in  FIG. 9 . The rotation of cap  70  in either rotational direction relative to base  72  is indicated by arrow  90  of  FIG. 11 .  FIGS. 10 and 11  further comprise diametrically opposed blades or paddles  82 ,  84  that sweep through cooperatively configured interior chambers  86 ,  88  of base  72  when cap  70  and base  72  are assembled as depicted in  FIG. 9 . When in use, rotation damper  40  will desirably contain an oily or oil-like fluid (not shown) that is disposed in chambers  86 ,  88  of base  72 . It will also be appreciated that fluid seals (not shown) are desirably provided to prevent or control fluid leakage between cap  70  and base  72 , and around the bores  74 ,  76 . Referring to  FIGS. 9-13 , when rotation damper  40  is subjected to rotational loading by the engagement of flexible shaft  37  ( FIG. 3 ) with bore  74  as helmet  22  is rotated left or right relative to shoulder pads  24  ( FIG. 3 ), paddles  84 ,  84  force fluid disposed in chambers  86 ,  88  of base  72 , forcing fluid through fluid passageways  92 ,  94 ,  96 ,  98  as seen in  FIGS. 12 and 13 . 
     In each instance where dynamic loading of dynamic connector  20  produces relative motion that causes fluid inside rotation damper  40  or elongation-compression damper  50  to be pushed through fluid passageways, it will be appreciated that the magnitude of damping will vary according to factors such as, for example, the number, cross-sectional area and surface configuration of the associated fluid passageways, the molecular weight, viscosity and lubricity of the fluid used, and the rate of movement of the paddle  82 ,  84  or piston  56  that is displacing the fluid. It will also be apparent to those of skill in the art upon reading this disclosure that those factors can be adjusted as needed in accordance with load factors likely to be encountered for a targeted activity, use environment and user demographic. 
     Referring to  FIGS. 14-20 , each of a plurality of tilt dampers  46  as disclosed in relation to this embodiment of the invention further comprises cap  100 , base  102  that are cooperatively configured to be assembled into slip-fit engagement with each other, with a ring  104  of interconnected, impact-absorbing pouches  105  disposed between them. Sufficient diametric clearance is desirably provided between cap  100  and base  102  of each tilt damper  46  that each cap  100  can tilt slightly in relation to the cooperatively engaged base  102  to permit some compression of a pouch  105  disposed between them in that portion of the circumference in which the tilting pressure is applied by flexure of flexible shaft  37  ( FIG. 3 ) relative to a centrally disposed longitudinal axis through elongation-compression damper  50  ( FIG. 3 ). Referring to  FIG. 15 , cap  100  further comprises annular rim  108  that cooperates with a plurality of evenly spaced, radially extending ribs (or spokes)  115  to define the upper portion of a plurality of recesses  114 . Transverse openings  110  are desirably provided in each rib  115  to provide clearance for connectors  128  between adjacent pouches  105  of pouch ring  104  ( FIGS. 14 and 19-20 ). Referring to  FIGS. 17-18 , base  102  further comprises an annular rim cooperatively configured to fit inside rim  108  of cap  100  ( FIG. 14 ). Base  102  further comprises a plurality of evenly spaced, radially extending ribs  118  that define recesses  116  that cooperate with recesses  114  of cap  100  to receive pouches  105  of pouch ring  104  when assembled as depicted in  FIG. 14 . Centrally disposed axial bores  112  through cap  100 ,  106  through base  102  and aperture  130  through pouch ring  104  are all desirably cooperatively aligned and are sized and configured to allow flexible shaft  37  ( FIG. 3 ) to pass through them. An oily or oil-like fluid  109  is desirably confined inside pouch ring  104  to provide cushioning and resistance to a force applied downwardly through dynamic connector  20  or by flexure of shaft  37  relative to shoulder pads  24  ( FIG. 3 ). 
     Those of ordinary skill in the art will also appreciate upon reading this specification and the description of preferred embodiments herein that modifications and alterations to the apparatus and methods may be made within the scope of the invention and it is intended that the scope of the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventor is legally entitled.