fig1 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 fig1 . furthermore , no free movement of the head is allowed . fig2 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 . fig3 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 . fig3 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 . fig3 b shows the preferred embodiment of the collar plate 36 of fig3 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 fig3 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 . fig4 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 fig3 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 . fig5 shows another embodiment of the invention of fig4 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 . fig6 a and 6 b show yet another embodiment that combines the function of spools 60 , 70 , 80 and 90 of fig4 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 . fig7 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 fig7 , 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 ( fig8 ) 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 fig8 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 fig8 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 . fig9 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 .
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 .