Abstract:
In a preferred embodiment, a restraint system is described for restraining a standing occupant in a vehicle such as a plane or helicopter. The restraint system includes a webbing strap that winds and unwinds from a spool assembly. The spool assembly includes a trigger assembly that locks a spool from rotation, a manual release assembly for manually releasing the trigger assembly and lock, and an adjustable payout assembly that determines the maximum length that the webbing strap can be pulled out before stopping (i.e., the number of rotations of the spool). The trigger assembly can trigger the lock assembly from one or more sensors. Further, the trigger assembly can be arranged to automatically unlock after a triggering event, manually unlocked after a triggering event or a combination of the two for different sensors.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a divisional of U.S. patent application Ser. No. 12/372,658 filed Feb. 17, 2009 entitled Restraint System, which claims priority to U.S. Provisional Application Ser. No. 61/028,753 filed Feb. 14, 2008 entitled Crew Restrain System, both of which are hereby incorporated herein by reference in their entireties. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Vehicles, such as aircraft, often include restraint systems to prevent occupants from unwanted movement and injury. Typically, these restraint systems restrain the occupant from movement by releasably strapping the occupant to a chair or similar vehicle furniture. 
         [0003]    However, some vehicles, such as helicopters or air cargo delivery planes may require an occupant to move about the interior of the vehicle. Intentional or unintentional vehicle motion such as turbulence or banking into a turn can cause an occupant to lose their balance or be thrown about the vehicle&#39;s interior. In some open vehicles such as rescue helicopters and military cargo planes, the occupant is in further danger of being thrown from the vehicle. 
         [0004]    Therefore, what is needed is an occupant restraint system that allows an occupant to move about the interior of a vehicle, yet restrains them from unwanted movement and other dangers. 
       SUMMARY OF THE INVENTION 
       [0005]    In a preferred embodiment, a restraint system is described for restraining a standing occupant in a vehicle such as a plane or helicopter. The restraint system includes a webbing strap that winds and unwinds from a spool assembly. The spool assembly includes a trigger assembly that locks a spool from rotation, a manual release assembly for manually releasing the trigger assembly and lock, and an adjustable payout assembly that determines the maximum length that the webbing strap can be pulled out before stopping (i.e., the number of rotations of the spool). The trigger assembly can trigger the lock assembly from one or more sensors. Further, the trigger assembly can be arranged to automatically unlock after a triggering event, manually unlocked after a triggering event or a combination of the two for different sensors. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    These and other aspects, features and advantages of which embodiments of the invention are capable of will be apparent and elucidated from the following description of embodiments of the present invention, reference being made to the accompanying drawings, in which 
           [0007]      FIG. 1  illustrates a perspective view of a restraint system attached to an occupant within a vehicle according to a preferred embodiment; 
           [0008]      FIG. 2  illustrates a magnified perspective view of the restraint system and occupant of  FIG. 1 ; 
           [0009]      FIG. 3  illustrates a perspective view of a spool assembly of  FIG. 1 ; 
           [0010]      FIG. 4  illustrates a perspective view of the ratchet and pawl assembly according to a preferred embodiment; 
           [0011]      FIG. 5  illustrates a perspective view of only the ratchet and pawl assembly of  FIG. 4 . 
           [0012]      FIG. 6  illustrates a disassembled perspective view of a trigger assembly and manual release assembly according to a preferred embodiment; 
           [0013]      FIG. 7  illustrates a perspective view of the trigger assembly and manual release assembly of  FIG. 6 ; 
           [0014]      FIG. 8  illustrates a magnified perspective view of the trigger assembly of  FIG. 7 ; 
           [0015]      FIG. 9  illustrates a perspective view of an adjustable payout assembly according to a preferred embodiment; 
           [0016]      FIG. 10  illustrates an exploded cross sectional view of the adjustable payout assembly of  FIG. 9 ; 
           [0017]      FIG. 11  illustrates a perspective view of an dual trigger assembly according to a preferred embodiment; 
           [0018]      FIG. 12  illustrates a perspective view of the dual trigger assembly of  FIG. 10 ; and 
           [0019]      FIG. 13  illustrates an exploded perspective view of the dual trigger assembly of  FIG. 11 . 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0020]    Specific embodiments of the invention will now be described with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements. 
         [0021]    Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
         [0022]      FIGS. 1 and 2  illustrate a preferred embodiment of an occupant restraint system  100  for a vehicle, such as a plane or helicopter. Generally, the occupant restraint system  100  includes a spool assembly  106  and a webbing strap  108  that is selectively wound and unwound from the spool assembly  106 . 
         [0023]    Preferably the spool assembly is pivotally mounted to the side or ceiling of a vehicle&#39;s interior  102  by pivot bracket  112 . This arrangement allows the spool assembly  106  to pivot in any direction as the occupant  110  moves through the vehicle&#39;s interior  102 . 
         [0024]    The webbing strap  108  is preferably latched to a harness  110  worn by an occupant. As the occupant  110  moves within the vehicle&#39;s interior  102 , the spool assembly  106  releases and retracts the webbing strap  108  as needed. However, during sudden or forceful movement, the spool assembly  106  locks, preventing further extension of the webbing strap  108  and thereby preventing excessive movement of the occupant  110 . 
         [0025]    In addition to or in place of the pivot bracket, the spool assembly can be connected to a trolley device that runs along a track as seen in U.S. Pat. No. 7,275,710, the contents of which are hereby incorporated by reference. Hence, the user can walk along an extended length of a vehicle (e.g., the length of an airplane) while attached to the restrain system. 
         [0026]      FIG. 3  illustrates a magnified view of the spool assembly  106 , including a framework  126 , outer coverings  114  and  116 , a webbing strap payout adjustment mechanism  118  and a manual lock reset handle. When the spool assembly  106  is caused to lock further spooling of the webbing strap  108  (e.g., due to rapid webbing payout velocity), the user can release the spool assembly  106  by pulling on the spring-biased manual reset handle  122 . 
         [0027]      FIGS. 4-8  illustrate various views of the trigger mechanism of the spool assembly  106 . Turning first to the ratchet and pawl engagement assembly (seen best in  FIGS. 4 and 5 ), this assembly prevents the spool  150  from rotating during a triggering event (e.g., a crash or sudden acceleration) by way of a first pawl member  142  that selectively engages a first spool ratchet  150  and a second pawl member  156  that selectively engages a second spool ratchet  154 . The first pawl member  142  is biased towards the first spool ratchet  150  by pawl spring  140 . The second pawl member  156  is linked to the first pawl member  142  via a connecting shaft  155 , allowing the second pawl member  156  to move in unison with the first pawl member  142 . 
         [0028]    During normal operation, a trigger mechanism  121  (seen best in  FIGS. 6 and 7 ) maintains a pawl pin  142 A and therefore the first pawl member  142  and second pawl member  156  in a raised position, away from the jagged surfaces of ratchets  150  and  154 . When the trigger mechanism  121  “triggers”, it releases any resistance on the pawl pin  142 A and thereby allows the pawls  142  and  156  to be biased against the ratchets  150  and  154 . This released pawl position stops the movement of the spool  152 . 
         [0029]    The trigger mechanism  121  includes a rotationally mounted trigger plate  120  having a plurality of radial engagement members  120 B and a plurality of perpendicular engagement members  120 A. The radial engagement members have various uses in the trigger mechanism  121 . For example, a first radial engagement member is in contact with a fixed spring  124  which biases the trigger plate  120  for movement in a counter clockwise rotational direction. In another example, a second radial engagement member  120 B contacts and maintains the unlocked spool position by pressing against the pawl pin  142 A. In yet another example, a third radial engagement member  120 B contacts lever  136  of an acceleration sensor  128 . 
         [0030]    The acceleration sensor  128  includes a spherical weight  130  that is freely positioned over cup  132 . Preferably, an additional enclosure is provided around the weight  130  to prevent it from completely moving off of cup  132 . A lower post portion of the cup  132  contacts a lever pin  136 A, biasing the lever  136  downward against radial engagement member  120 B of the trigger plate  120 . The spring  134  preferably reduces the amount of weight that weight  130  places on the pin  136 A to allow for greater sensitivity of the acceleration sensor  128 . Additionally, the interior surface of the cup  132  includes conical or ramped surfaces for sideways or rolling acceleration. 
         [0031]    When the vehicle suddenly accelerates (e.g., drops downward and abruptly stops from a crash), the weight  130  increases pressure on the pin  136 A (e.g., from the sudden stop in acceleration) and thereby the lever  136 . As the lever  136  moves downward against the radial engagement member  120 B, the trigger plate  120  rotates in a clockwise direction, allowing the pawls  142  and  156  to move downward and stop the ratchets  150  and  154  from rotating. When the vehicle banks or rolls hard, the weight  130  will move to the side of the cup  132  against the conical or ramped surface. Since the previously described weight enclosure prevents the weight  130  from moving upwards, away from the cup  132 , the cup  132  and its pin are pushed downward, triggering the trigger plate  120  as previously described. 
         [0032]    The trigger mechanism  121  can also be activated when the spool  152  is rotated too quickly as opposed to rotating with too much acceleration. Prior restraint trigger mechanisms tend to trigger a locking mechanism at different angular speeds when pulling out the webbing strap. For example, pulling a webbing strap at a constant linear speed away from a restraint device can result in the spool moving more slowly initially (the spool is larger in diameter when fully wound with the webbing) and more quickly after the webbing has been pulled out a distance (the spool is smaller in diameter when less webbing is on the spool). The trigger mechanism  121  reduces this behavior by with two opposed, biased plates  144  and  146 . 
         [0033]    More specifically, the first velocity plate  144  and the second velocity plate  146  are positioned against the trigger plate  120  and rotate with the spool  152 . Both velocity plates  144  and  146  include a mounting groove that allows the plates  144  and  146  to be captured for rotational movement and slide away from the axial. Two springs  146  bias the plates  144  and  146  against each other during normal operation. When these plates  144  and  146  rotate too quickly, the rotational velocity pulls the plates  144  and  146  away from each other, against the bias of the springs  138 . As the plates  144  and  146  move away from each other, their engagement members  144 A and  146 A contact the perpendicular engagement members  120 A, causing the trigger plate  120  to rotate and trigger the pawl  142 . It should be understood that changing the tension or spring constant of springs  138  can adjust the threshold at which the plates  144  and  146  engage the perpendicular engagement members  120 A. 
         [0034]    Preferably, the relative spring rates or spring constants of the previously described triggering mechanisms (i.e., springs  124 ,  134  and  140 ) are such that once the triggering mechanism  121  has been triggered it will not disengage until manually released by the user. As seen best in  FIG. 7 , manual release of the triggering mechanism  121  is controlled by pulling back the manual reset handle  122 . When triggered, the trigger plate  120  has rotated in a clockwise direction, bringing one of the radial engagement members  120 B closer to or in contact with the pin  122 A of the handle  122 . The user pulls back on the handle  122 , against the bias of spring  123  to press the pin  122 A against the radial engagement member  120 B, thereby rotating the trigger plate  120 . When the handle  122  has been pulled back far enough, a radial engagement member  120 B near the pawl  142  lifts pawl pin  142 A up to unlock the spool  152 . Hence, the spool assembly  106  can again extend and retract the webbing strap  108  as needed by the occupant. 
         [0035]      FIGS. 9 and 10  illustrate the previously mentioned adjustable payout assembly  160  that stops the webbing strap  108  from unwinding from the spool  152 . More specifically, the payout assembly  160  triggers a payout pawl  174  that engages the ratchet  154  (seen in  FIG. 4 ) or alternately a third ratchet. 
         [0036]    The payout assembly  160  is actuated by rotation of a lead screw  162  that is keyed or captured by the spool  152 . In this respect, the lead screw  162  is free to move along an axis of the spool  152  while also rotating with the spool  152 . A compression spring  178  is coupled to an interior of the lead screw  162  to preload the screw  162  away from the spool  152 . A trigger nut  166  is threaded over the lead screw  162  and captured by a keyway  182 A of the housing  182 , allowing the trigger nut  166  to move axially within the keyway  182 A. 
         [0037]    As the trigger nut  166  moves axially outward, away from the spool  152 , a pin  180  contacts and bottoms out on one of the plurality of indentations  164 . Since the trigger nut  166  can no longer move axially away from the spool  154 , the lead screw  162  unscrews from the trigger nut  166  and thereby move toward the spool  154 . As the end of the lead screw  162  approaches the trigger plate  172 , a trigger post  168  on the lead screw  162  contacts and engages one of the locking dogs  170  which are raised from the surface of the trigger plate  172 . 
         [0038]    Normally, the spring  176  biases the trigger plate  172  in a clockwise direction so that the trigger member  172 A lifts up the payout pawl pin  174 A and therefore the payout pawl  174 , allowing the spool  152  to rotate freely. However, when the trigger plate  172  rotates in a counterclockwise direction, driven by the rotation of the lead screw  162 , the trigger member  172 A moves away from the payout pawl pin  174 A, allowing the payout pawl  174  to drop on to the ratchet  154  and stop further movement of the spool  152 . 
         [0039]    When pressure from the lead screw  162  is removed from the trigger plate  172 , the spring  174  urges the trigger plate  172  and the trigger member  172 A back in a clockwise position so as to lift the payout pawl pin  174 A and thus the payout pawl  174  in a raised position, away from the ratchet  154 . In this respect, the spool  152  is free to rotate again (to wind up the webbing strap  108 . 
         [0040]    The point at which the payout assembly  160  locks can be adjusted by a user by rotating the adjustment knob  118 . The previously discussed pin  180  is eccentrically positioned inside the adjustment knob  118 . Therefore, rotation of the knob  118  aligns the pin  180  with different indentations  164  on the trigger nut  166 . Each of the indentations  164  are located at different depths from the surface of the trigger nut  166  and therefore allow the trigger nut  166  to move to various distances from the trigger plate  172 . Hence, the payout assembly  160  will lock at various, user adjustable positions. 
         [0041]      FIGS. 11-13  illustrate an alternate preferred embodiment of a trigger assembly  190  that engages a first trigger mechanism that automatically releases when tension is released and a second trigger mechanism that must be manually released. In this respect, the spool  152  can be locked by pulling on the webbing strap  108 , and then unlocked by releasing tension on the webbing strap  108 . However, if the pulling exceeds a certain threshold, the spool  152  must be manually released. 
         [0042]    In addition to the previously described pawl  142 , an automatic reset pawl  198  is pivotally mounted via pivot  198 B underneath ratchet  150 . A pawl pin  198 A is connected to a side of the pawl  198  and extends through an aperture in the framework  126 . 
         [0043]    As best seen in  FIG. 13 , trigger assembly  190  includes an automatic-unlock trigger plate  192  that is engaged by velocity plates  144  and  146  as previously described in this specification. The automatic-unlock trigger plate  192  is rotationally biased in a counter clockwise direction via a spring (not shown) similarly to the previously described plate  120 . This rotational bias urges radial engagement member  192 B toward the pawl pin  198 A, preventing the pawl  198  from contacting the ratchet  150 . 
         [0044]    When the velocity plates  144  and  146  engage the axial engagement members  192 A, the plate  192  is rotated in a clockwise direction, causing member  192 B to release pressure on pawl pin  198 A and thereby causing the pawl  198  to engage the ratchet  150 . When pressure is released on the webbing strap  108 , the velocity plates  144  and  146  release their engagement of the plate  192 , allowing the spring to rotate the plate  192  back in a counter-clockwise direction to reengage the pawl pin  198 A and thereby release the pawl  198  from the ratchet  150 . 
         [0045]    As previously discussed, if the force and or acceleration of the webbing strap exceeds a threshold, a manually released trigger mechanism is activated. This threshold is created, in part, by a resistance spring  195  in a recessed spring well  194 B. The resistance spring  195  is engaged with the spring well  194 B and a ramp (not shown) on the back of plate  192 . The resistance spring  195  compresses when the plate  192  is rotated with a relatively slow or low acceleration. However, faster rotational speed or acceleration overcomes the compression of the spring  195 , causing the mating plate  194  to rotate in a clockwise direction. A pin on radial engagement member  194 C contacts and pushes radial engagement member  196 B of the manual unlock trigger plate  196 , thereby causing trigger plate  196  to rotate in a clockwise direction. This rotation releases pressure of radial engagement member  196 A on the pawl pin  142 A, causing the pawl  142  to lower onto the ratchet  150  and lock the spool  152 . 
         [0046]    Preferably, the trigger plate  196  is spring biased in a counterclockwise position, but with a force that will not overcome rotation of the trigger plate in the locked position. In other words, once the trigger plate  196  locks, it remains in its locked, rotated position. 
         [0047]    While not shown in  FIGS. 11-13 , a manual release mechanism can be used to release the trigger plate  196 , thereby rotating the plate  196  back to its original position and lifting the pawl  142 . For example, the manual release mechanism shown in  FIGS. 5-8  (i.e., the handle  122 , spring  123  and pin  122 A) can be used to release the trigger plate  196 . 
         [0048]    Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof.