Abstract:
The present invention may comprise a helmet worn by a person, with additional elements to dampen, restrain or totally block rotational movement upon the sensing of severe rotational movement of the head. This device prevents serious brain and cervical spine injury by restraining or totally blocking rotational movement of the head in response to severe acceleration/deceleration.

Description:
RELATED APPLICATIONS 
     This application is a national phase filing under 35 U.S.C. 371 of International Application No. PCT/US2007/009028, filed on Apr. 12, 2007, and claims the benefit of U.S. Provisional Application No. 60/791,603, filed Apr. 12, 2006, the entirety of these applications are hereby incorporated herein by reference for the teachings therein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to head and neck rotation acceleration/deceleration restraint and dampening systems that reduce or eliminate damage to or shearing of brain matter, axons and cervical spinal cord and spine. In particular, this invention provides a dampening device to prevent the brain from substantial rotational acceleration or deceleration that would lead to tearing of brain or cervical spine tissue. 
     BACKGROUND OF THE INVENTION 
     The brain generally consists of an outer layer of grey matter or cortex where neurons are located and white matter or axons, which connect the gray matter areas. Disruption of white matter connections disables brain function. Symptoms can be as mild as memory and attention difficulties, and as serious as a coma state. 
     Diffuse axonal injury (DAI) results from rotational shear forces that tear white matter tracts. DAI is common in traumatic brain injury (TBI) and accounts for persistent cognitive deficits and symptoms. 
     Acceleration/deceleration TBI studies in animals and clinical investigations have attributed cognitive deficits to DAI. Distinguished from focal contusion without shearing, DAI is defined as damage to axons at the gray/white matter junction of the cerebral hemispheres, corpus callosum and dorsolateral midbrain and often involves the superior cerebellar peduncles. These deep white matter abnormalities can be detected by a MRI and are associated with poorer neuropyschological test performances and poor long-term outcome. 
     Rapid acceleration and deceleration of a person&#39;s head, especially with a rotational component causes serious damage to the white matter connections in the brain. This is the most common form of brain injury and occurs in car crashes, falls, sporting accidents and recently in war as a consequence of road-side bombs that cause a blast wave to whip the head producing rotational shear injury. 
     In addition, rapid acceleration/deceleration in flexion, extension or rotation movements can cause fractures, torn ligaments, disc herniations, cervical spine and spinal cord injury and other damage of the neck cervical spine. 
     This patent application describes embodiments to dampen or minimize the rotational component of rapid acceleration/deceleration that can cause damage to the brain or cervical spine while allowing free movement at lower accelerations. The acceleration/deceleration is calculated for the head and cervical spine with respect to the torso. 
     An object of the invention is to reduce the incidence of brain, cervical spine, and spinal cord injury in crash victims, athletes and others while providing unencumbered head motion and range during normal circumstances. 
     Another object is to provide such a device, which can be conveniently worn during normal circumstances and is a device which is simple to use and is automatically displayed. 
     Still another object of this invention is to provide a device capable of widespread use and exploitation. 
     Other objects, advantages and features of this invention will become more apparent hereinafter. 
     SUMMARY OF THE INVENTION 
     The invention provides advantages over the prior art by providing automatic dampening of the motion of a user&#39;s head when dangerously large accelerations are present, but creating no or very little inconvenience to the user in normal circumstances. In some cases rotational movement may be completely prevented or always allowed, depending on the threshold settings for the restraint system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a prior art apparatus for restraining head movement during a traumatic event. 
         FIG. 2  is a front view of the three rotational planes through the head. 
         FIGS. 3   a  and  3   b  are side and rear views of the preferred embodiments of this invention. 
         FIGS. 4   a  and  4   b  are perspective views of another embodiment of the present invention using an airbag collar, both before and after deployment. 
         FIG. 5  is a top view of an alternative embodiment of the present invention. 
         FIGS. 6   a  and  6   b  are front and top views of a vehicle occupant wearing an embodiment of the present invention head retraining system utilizing tethers and recoiling spools. 
         FIGS. 7   a  and  7   b  are side perspective views of another alternative embodiment of this invention. 
         FIG. 8  is a front view of another embodiment of this invention. 
         FIGS. 9   a  and  9   b  are side views of another embodiment of this invention utilizing football helmet type apparatus. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  shows a prior art device (as disclosed in U.S. Pat. No. 6,931,669 to Trevor P. Ashline) to control head movement during rapid acceleration/deceleration which straps a user&#39;s helmet  2  to a support plate  4  worn by the user with head strap  6 . Strap  8  further secures the support plate  4  to the user. A fixed strap system is an improvement and life safer over just wearing a helmet by itself. However this system is not suitable for protecting a person&#39;s brain in the event of rapid rotational accelerations of the head, both in vehicular and non-vehicular situations, because there is no way to detect such movement in the device of  FIG. 1 . Furthermore, no free movement of the head is allowed. 
       FIG. 2  shows the three planes in which the head can rotate. The coronal plane  10  lies roughly parallel to the chest. Moving one&#39;s head side to side, or moving the ear toward the shoulder, is an example of head rotation in the coronal plane. The axial plane  12  perpendicular to coronal plane  10  lies roughly parallel to the top of the head, like the rim of a hat. Shaking one&#39;s head to indicate “no, is an example of head rotation in the axial plane. The sagittal plane  14  is perpendicular to both planes  10  and  12 , and bisects the left side of the head from the right. Nodding one&#39;s head to indicate, “Yes,” is an example of head rotation in the sagittal plane. 
       FIGS. 3   a  and  3   b  show preferred embodiments of this invention in which a person  31  wears a helmet  33  having the appearance of a conventional football helmet with a face guard  34 . This invention prevents rotation of the head in all three planes with respect to the torso. In a preferred embodiment, it is important to find a fixed reference, which hardly moves with respect to the torso. Such a fixed reference is the neck  35  and a neck or collar reference, plate  36 , similar to a standard collar, which is worn by the user at the base of the neck.  FIG. 3   a  shows a left side view of the invention, and the right side view would be substantially similar. A side front tether  37  is attached between a side front point  38  on the helmet and a front collar spool  39  and this tether detects extension in the sagittal plane. A side rear tether  40  is attached a side rear point  43  on the helmet and a rear collar spool  42  and this detects flexion in the sagittal plane. Tether  40   a  is connected between front helmet attachment  38  and middle spool  41 . This tether detects axial rotation or the face rotating away from spool  39 . Tether  40   b  is connected between the rear side attachment  43  and middle spool  41  and detects axial rotation or the face rotating toward spool  39 . Tethers  40   a  and  40   b  together detect coronal movement with the whole head angling away from spool  41 . 
       FIG. 3   b  shows the preferred embodiment of the collar plate  36  of  FIG. 3   a  as a fixed reference to the torso in which a body harness  44  comprised of a chest strap  45  and a vertical connecting strap  46  attach to a collar plate  36 . A rear tether  47  is connected between a rear collar spool  48  and a rear attachment point  49  on the helmet and this detects flexion in the sagittal plane in addition to tethers  40 . Rear side tethers  40  are shown attached between back collar spool  42  and side rear point  43  on the helmet. Harness  44  substantially fixes collar plate  36  with respect to the torso. 
     The preferred embodiment of this invention in  FIGS. 3   a / 3   b  uses a series of small tethers or belts attached between the helmet  33  and the collar reference plate  36  that do not significantly interfere with normal motion, but effectively dampen and slow accelerations of the head so as to greatly lessen the likelihood of injury. These tethers can be on a spool or pulley that allows the tether to be extended as the user moves his head, but can lock or slow the tether if there are significant accelerations detected. These tethers may be designed to further extend and dampen the motion of the head when the spools have been locked by an activation module. The spools and/or reference plate may provide some or all of the needed damping. Alternatively, the material used in the tether can have inherent properties to allow stretching at slow but not high accelerations. 
       FIGS. 4   a  and  4   b  show another embodiment of this invention with a different type helmet attached to a shoulder reference plate. While a shoulder reference plate may experience more motion with respect to the torso, it is a valuable alternative because of the size of the shoulder reference plate. Shoulder reference plate  120  is similar to shoulder pads and covers some portion of the user&#39;s back, continues over the shoulders and covers some portion of the chest with belt  140  to allow the user to adjust the fit. Reference plate  120  is generally maintained in place and is the reference or anchor against which rotational movement is prevented. Spools  60 ,  70 ,  80 ,  90 ,  100 , and  110  are mounted on this reference plate. These spools are similar to those in  FIGS. 3   a  and  3   b  and are mechanically or electro-mechanically controlled, and in the event of an impact or dangerously large acceleration they will act to slow, dampen and stop the movement of the head relative to the reference plate  120 . The spool mechanism may also incorporate a pretensioning system to eliminate slack in the tethers and potentially best position the user&#39;s head for surviving the impending impact and acceleration. 
     Spools  60  and  70 , located on top of the right and left shoulders respectively, control head rotation in the axial plane  12  using tethers  62  and  72  with attachments to the helmet  104  at points  64  and  74  located to the right and left of the chin. Relocating these components may offer advantages in specific applications. Spools  80  and  90 , also located on top of the shoulders, control head rotation in the coronal plane using tethers  82  and  92  with attachments to the helmet  84  and  94  being near the top or crown of the helmet. Spools  100  and  110 , located near the user&#39;s sternum and spine respectively, control head rotation in the sagittal plane using tethers  102  and  112  with attachments  104 ′ to the helmet near the chin and  114  on the back of the helmet. 
       FIG. 5  shows another embodiment of the invention of  FIGS. 4   a  and  4   b  in which the tethers&#39; attachment points to the helmet can have alternative locations and still be effective. Specifically it shows tethers  62 ′ and  72 ′ between spools  60 ′ and  70 ′ respectively and attachment points,  64 ′ and  74 ′, respectively. These are attached to the back of the helmet  65  instead of near the chin at the front and detects axial movement. 
       FIGS. 6   a  and  6   b  show yet another embodiment that combines the function of spools  60 ,  70 ,  80  and  90  of  FIG. 4  into just two spools  66  and  76  with tethers  67  and  77  attached to the helmet  69  at connections  68  and  78 . 
     There are other ways to protect the head from rapid rotational accelerations, while causing little inconvenience to the wearer. 
       FIGS. 7   a  and  7   b  illustrate still another embodiment and show a helmet  20  with an inflatable restraining member that stores as a collar  22 . An activation module  24  comprises a system of sensors that detect collisions, impacts or large accelerations of a predetermined value, which may be dangerous to the wearer. When this activation module  24  receives a “deploy” signal from the impact or acceleration sensors that are mounted on the vehicle, or on the user, it can activate the rapid inflation of the collar  22 . The collar may deploy like a vest  30  as shown in  FIG. 7 , extending down the wearer&#39;s chest and back to provide resistance to accelerations of the head relative to the body—especially rotationally. The vest may include arm cutouts  32 . The collar is similar to airbags used in automobiles. The collar  22  may also expand to a smaller size than vest  30 . When the user wears this helmet, there may be little or no contact between the collar and the wearer, providing unencumbered motion and range. The activation module  24  can be located on and/or in the helmet, and houses the electronics needed for activating the inflation of the airbag collar or activating some other form of anti-rotational means. Sensors, accelerometers and complete airbag deployment systems may be employed and are common and well known in the art. Examples of these systems and their “sensing module” equivalents can be found in U.S. Pat. Nos. 5,338,062 and 7,165,785, which patents are incorporated herein by reference. 
     A conventional helmet may also include a see through visor  26 , which can pivot at joint  28 . 
     Another embodiment of this invention utilizes a collar  50  ( FIG. 8 ) that is connected to the helmet and extends to reference plate  120 ′, which may be affixed to the torso, shoulders, seat or other component. When activation module  24 ′ receives a “deploy” signal from the impact or acceleration sensors, it will stiffen the collar to dampen acceleration and limit the total travel of the head. This collar may be similar to an airbag, and is stiffened by rapid inflation. 
     Another embodiment utilizes a collar similar to that shown as  50  in  FIG. 8  between the helmet and shoulders that is easily flexed and rotated, except during large and dangerous accelerations when it behaves like a much stiffer material—resistant to fast deflection. This material may be a Silicone and/or a foam or fluid. 
     The tethers shown in the various embodiments are built into a spool and function similar to an ABS disk brake to achieve significant damping rather than sudden stopping. Additionally, the tether could comprise a sacrificial tether material for one time use to be combined with a locking spool. Additionally, the tether material could be formed of the material so described in  FIG. 8  which stiffens upon sensing high acceleration. 
     The sensor used, as described above, may comprise multi-axis accelerometers, rotational accelerometers, contact sensors, and/or position sensors, which measure the movement of the spools. 
     The placement of the sensors may comprise a coordinated array of sensors which can be located on the vehicle, torso harness and/or helmet to provide early detection of impact independent of where the impact occurs. 
       FIGS. 9   a  and  9   b  illustrate this invention used with football like helmets  800  which illustratively show a plurality of tethers  802  attached to a plurality of respective spools  804  and also being attached at various points  806  and  808  on the helmet. 
     It is understood that the various mechanisms to control rotational movement of the head can be “switched” off or physically removed so that the head and torso are free from any possible restraint. 
     It should be understood that the preferred embodiment was described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly legally and equitably entitled.