Patent Abstract:
A leg restraint for side-seated vehicle occupants that includes a leg-restraining member for being mounted in proximity to a side-facing vehicle seat and selectively moveable between a deployed, laterally-extending leg-protecting position and a retracted, non-leg interfering position, and a sensor for detecting abrupt movement in the direction of forward travel of the vehicle incident to an abrupt deceleration of the vehicle and outputting a signal. A gas-inflatable bag is positioned operatively proximate the leg-restraining member and is responsive to the signal output by the sensor for inflating and deploying the leg-restraining member upon the occurrence of the abrupt deceleration of the vehicle.

Full Description:
This application is a continuation-in-part of and claims priority from pending patent application Ser. No. 13/907,079, the full contents of which are incorporated into this application by reference. 
    
    
     TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to a leg restraint device for side-seated vehicle occupants. In particular, the invention relates to a leg restraint device for side-seated occupant of, for example, corporate aircraft of the type offering side-facing seats for passengers. The disclosed invention has application in any form of vehicle transportation where passenger or occupant seats may be mounted in a side-facing orientation in relation to the direction of forward travel of the vehicle, such as an aircraft. The FAA has released Policy PS-ANM-25-03-R1 requiring leg flail prevention for occupants seated in side-facing seats when the occupant&#39;s upper leg is restricted by contact with the seat itself and/or with an interior component. In order to provide adequate occupant protection, the lower legs must also be restricted in a similar manner to avoid upper leg femur bone torsion. Thus, there is a need for a device that will provide this lower leg support during a dynamic event such as a crash. 
     Violent or abrupt deceleration can cause high g-force lateral loading on a side-facing passenger, causing lateral leg movement and leg rotation about the knee and femur. This can cause dislocations, muscle and tendon injuries and fractures due to the restraint exerted on the passenger&#39;s torso by seat belts and/or arm rests while the legs are unrestrained. However, belts or similar restraints on the legs are not advisable due to the additional time needed to remove the restraints, as well as the possibility that injuries to the passenger may make it difficult for either the passenger or emergency personnel to remove such restraints. 
     Therefore, there is a need for a type of leg restraint that provides protection to the legs of side-facing seat occupants in the event of a crash or other rapid deceleration, while not inhibiting rapid egress from the seat after the event. 
     The leg flail prevention device disclosed in this application deploys automatically and is designed to be triggered by the same sensor and trigger that is used to deploy inflatable shoulder harness air bags also installed on the side-facing seat. As such, for installations that restrict the side-facing occupant&#39;s upper legs in the forward direction, the automatic leg flail prevention device is utilized to introduce the higher level of occupant protection. In the embodiment disclosed in the application, a linear restraint panel presents the main restriction to the occupant&#39;s lower legs to prevent leg flail. This restraint panel is deployed by the inflation force of an attached air bag. Once the air bag deploys the restraint panel, the portion of the air bag attached to the restraint panel further inflates between the restraint panel and the leg to cushion the impact of the occupant&#39;s legs with the restraint panel. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a leg restraint that provides protection to the legs of side-facing seat occupants in the event of a crash or other rapid deceleration. 
     It is another object of the invention to provide a leg restraint device that provides protection to the legs of side-facing seat occupants in the event of a crash or other rapid deceleration, while not inhibiting rapid egress from the seat after the event. 
     It is another object of the invention to provide a leg restraint device that provides protection to the lower legs of side-facing seat occupants in the event of a crash or other rapid deceleration, but that need not be deployed during taxi, take-off and landing (“TTOL”). 
     It is another object of the invention to provide a leg restraint that includes an air bag as a means of deploying a linear restraint panel that acts to restrict lateral movement of the lower legs of a side-seated occupant. 
     It is another object of the invention to provide a leg restraint that includes a deployable air bag as a means of cushioning and restricting lateral movement of the lower legs of a side-facing seat occupant. 
     It is another object of the invention to provide a leg restraint that includes a deployable air bag utilized to deploy outwardly from the seat a linear restraint panel that acts to restrict lateral movement of the lower leg, whereupon the air bag continues deploying and serves the further purpose of cushioning and restricting lateral movement of the lower legs of a side-facing seat occupant. 
     These and other objects and advantages of the invention are achieved by providing a leg restraint for side-seated vehicle occupants, and including a leg-restraining member adapted for being mounted in proximity to a side-facing vehicle seat and selectively moveable between a deployed, outwardly-extending leg-protecting position and a retracted, non-leg interfering position and a gas-inflatable air bag positioned operatively proximate the leg-restraining member and responsive to a signal output by a sensor for inflating the air bag and deploying the leg-restraining member upon the occurrence of an abrupt deceleration of the vehicle sensed by the sensor. 
     According to another embodiment of the invention, a biasing member cooperates with the leg-restraining member to move the leg-restraining member into the retracted position after impact of an occupant&#39;s leg against the leg-restraining member. 
     According to another embodiment of the invention, the air bag is adapted for being positioned for deployment between the leg-restraining member and the legs of the seat occupant to cushion the legs against direct impact against the deployed leg-restraining member. 
     According to another embodiment of the invention, the air bag inflates during a first phase to deploy the leg-restraining member and further inflates during a second phase into a position between the leg-restraining member and the legs of the seat occupant to cushion the legs against direct impact against the deployed leg-restraining member. 
     According to another embodiment of the invention, the air bag inflates during a first phase to deploy the leg-restraining member and further inflates during a second phase to a position between the leg-restraining member and the legs of the seat occupant and beyond an outermost extent of the deployed leg-restraining member to cushion the legs against direct impact against the deployed leg-restraining member. 
     According to another embodiment of the invention, a retractor is provided for returning the leg-restraining member back into its retracted position upon the leg-restraining member reaching its fully deployed position. 
     According to another embodiment of the invention, the retractor includes a spring having a bias that is initially overpowered by the operation of the air bag as the leg-restraining member is deployed, and is biased to return the leg-restraining member to its retracted position as the air bag deflates. 
     According to another embodiment of the invention, the air bag is adapted to inflate into a shape having its widest extent at its distal end. 
     According to another embodiment of the invention, the leg-restraining device includes a restraint panel having relatively upright side walls. 
     According to another embodiment of the invention, a sensor is provided for detecting abrupt movement of the vehicle in the direction of forward travel of the vehicle incident to an abrupt deceleration and for outputting a responsive signal to a trigger responsive to the signal from the sensor for activating the air bag. 
     According to another embodiment of the invention, a leg restraint is provided and is adapted for being mounted on a side-facing aircraft seat for protecting the legs of the seat occupant, and includes a restraint panel mounted in proximity to the side-facing aircraft seat and selectively moveable between a deployed, laterally-extending leg-protecting position and a retracted, non-leg interfering position. A sensor is provided for detecting abrupt movement of the vehicle in the direction of forward travel of the vehicle incident to an abrupt deceleration and outputting a responsive signal. An air bag is mounted on the restraint panel in a normally deflated configuration and in a position wherein, upon inflation, the air bag propels the restraint panel into the deployed position and then deflates. A trigger responsive to the signal output by the sensor is provided for inflating the air bag. A biasing member, for example, a spring, is provided that is initially overpowered by the operation of the air bag as the restraint panel is deployed, and is biased to return the restraint panel to its retracted position as the air bag deflates. 
     According to another embodiment of the invention, the restraint panel is mounted in a housing adapted for being positioned under the seat bottom of the side-facing aircraft seat. 
     According to another embodiment of the invention, the restraint panel includes a slide mounted in the housing for movement on at least one stationary guide shuttle mounted on an inner surface of the housing. 
     According to another embodiment of the invention, the air bag is adapted for being positioned for deployment between the restraint panel and the legs of the seat occupant to cushion the legs against direct impact against the deployed leg-restraining member. 
     According to another embodiment of the invention, the air bag is adapted to inflate during a first phase to deploy the restraint panel and to further inflate during a second phase to a position between the restraint panel and the legs of the seat occupant to cushion the legs against direct impact against the deployed restraint panel. 
     According to another embodiment of the invention, the air bag is adapted to inflate during a first phase to deploy the restraint panel and to further inflate during a second phase to position the air bag between the restraint panel and the legs of the seat occupant and beyond the outermost extent of the deployed restraint panel to cushion the legs against direct impact against the deployed restraint panel. 
     According to another embodiment of the invention, a spring is provided for returning the leg-restraining member back into its retracted position upon the leg-restraining member reaching its fully deployed position. 
     According to another embodiment of the invention, the spring has a bias that is initially overpowered by the operation of the air bag as the leg-restraining member is deployed, and is biased to return the leg-restraining member to its retracted position as the air bag deflates. 
     According to another embodiment of the invention, the air bag has a shape that is adapted to inflate into a shape having its widest extent at its distal end and to project outwardly beyond the distal end of the restraint panel at its fullest deployed extent. 
     According to another embodiment of the invention, the restraint panel includes a recess extending along a length of the restraint panel, and a guide shuttle mounted on the housing and having wheels engaging opposing top and bottom sides of the recess to guide the restraint panel between its retracted and deployed positions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
       The present invention is best understood when the following detailed description of the invention is read with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a side-seated aircraft seat, showing a leg restraint device according to a preferred embodiment of the invention in its retracted position; 
         FIG. 2  is a side elevation of a side-seated aircraft seat, showing a leg restraint device according to a preferred embodiment of the invention in its retracted position; 
         FIG. 3  is a perspective view of a side-seated aircraft seat, showing a leg restraint device according to a preferred embodiment of the invention in its deployed position; 
         FIG. 4  is a side elevation of a side-seated seat, showing a leg restraint device according to a preferred embodiment of the invention in its deployed position; 
         FIG. 5  is a partially-exploded view of one embodiment of the invention showing the air bag in its stowed, retracted position; 
         FIG. 6  is a partially-exploded view of one embodiment of the invention showing the air bag in its fully deployed position; 
         FIG. 7  is a vertical cross-section taken along line  7 - 7  of  FIG. 5 ; 
         FIG. 8  is an exploded view of one embodiment of the invention from a side opposite  FIGS. 5 and 6 ; and 
         FIG. 9  is a vertical cross-section taken along line  9 - 9  of  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now specifically to the drawings, the environment of the disclosure is an aircraft of the type having side-facing seats, such as seat  10 , having a seat bottom  12 , seat back  14  and an armrest/end bay  16 . Accordingly, a seat occupant sits with his or her back to the aircraft fuselage “A”, facing outward in a generally perpendicular direction in relation to the longitudinal dimension of the aircraft and its direction of forward travel. For this reason, the occupant is subject to substantial lateral g-force loading along the longitudinal axis of the aircraft in the event of an abrupt deceleration such as might result during hard braking or a forward-directed crash event. While the upper torso and the thigh area of the legs are restrained to some extent by the armrest  16  and the seat belt  18 , the lower legs are free to be projected laterally forward, rotating violently around an axis defined by the knees, causing potential serious injury to both the knees and lower legs unless they are restrained in some manner. Injury to the legs is a particularly serious concern since such injuries could prevent the passenger from being able to egress unaided from the aircraft in the event of an accident. 
     Thus, in accordance with the invention, a leg restraint device  20  is provided. As shown in  FIGS. 1 and 2 , the leg restraint device  20  is mounted under the seat  10  forward of the occupant in relation to the aircraft&#39;s direction of forward travel. The leg restraint device  20  includes two principal elements, a housing  22  mounted under the seat  10 , and a deployable restraint panel  24 , which includes a cap plate  28  on the distal end. During boarding, deplaning and normal flight, the leg restraint device  20  remains in a retracted condition, as shown in  FIGS. 1 and 2 . In the event of an emergency that may result in an abrupt deceleration, the restraint panel  24  is automatically deployed, as explained below. 
     The leg restraint device  20  as shown in the Figures is a “left-hand” oriented device shown mounted under a seat  10  and a left-hand side of the aircraft fuselage “A”, from the position of the seat occupant. A right-hand device constructed in accordance with the invention would be utilized on seats facing inward from the right-hand side of the aircraft fuselage “A.” In general, the left and right-hand versions both require mounting an air bag in a housing so that the air bag inflates against the leg of a seat occupant seated in a seat facing inward from the side of the aircraft fuselage, and are mirror constructions of each other. 
     As shown in  FIGS. 3 and 4 , the restraint panel  24 , when deployed, projects forwardly of the seat  10  into a position where the legs of the seat occupant are positioned behind the restraint panel  24  in relation to the aircraft&#39;s direction of forward travel. In the event of an actual abrupt deceleration of the aircraft, the occupant&#39;s legs are prevented from continued unrestrained forward motion by the restraint panel  24 . As described in further detail below, the restraint panel  24  is deployed by the inflation force imposed on the restraint panel  24  by an air bag  26  that is stored in the housing  22 . Upon the occurrence of an event requiring side restraint protection of the seat occupant, the air bag  26  is triggered and during a first phase inflates and deploys the restraint panel  24  by forcing it rapidly out of the end of the housing  22 . 
     During a second phase of the deployment of the air bag  26 , it continues inflating and projects outwardly along the side of the deployed restraint panel  24  nearest the seat occupant&#39;s foot and lower leg. In this configuration, shown in  FIGS. 3 and 4 , the air bag  26  provides an air cushion between the seat occupant&#39;s feet and lower legs that prevents direct contact with the inner side of the restraint panel  24 . Note that in its fully deployed configuration, the air bag  26  extends beyond the fully deployed position of the cap plate  28  of the restraint panel  24  in order to fully protect the seat occupant&#39;s feet and lower legs. 
     The restraint panel  24  is caused to retract back in to the housing  22  by the rapid deflation of the air bag  26 , as is typical of air bag operation. This retraction occurs very rapidly and thus clears the area around the seat  10  for rapid, unrestricted egress by both the seat occupant and other aircraft occupants who may have to move past the seat  10  in order to egress from the aircraft. 
     Referring now to  FIGS. 5-9  the housing  22  of the restraint device  20  is formed from two stationary housing covers  30 ,  32 . The restraint panel  24  and the cap plate  28  slide in and out of the retracted and deployed positions on a wheeled guide shuttle  34  mounted on the inner surface of housing cover  32 . Note that the restraint panel  24  has a “corrugated” cross-section,  FIGS. 7 and 9 , that provides the necessary spacing for the movable components. The guide shuttle  34  is captured in and rides along a central, longitudinally-extending recess  36  in the restraint panel  24 . 
     The restraint panel  24  is attached to a retractor that includes a spring housing  38  mounted on the cover  30 . A vertical pin  40  mounts a coiled steel spring  42  that is mounted on the restraint panel  24  and biased towards its retracted position. See  FIG. 5 . Activation of the air bag  26  overcomes the bias of the spring  42  during inflation, allowing the restraint panel  24  to deploy, as shown in  FIG. 6 . As inflation ends and deflation begins, the spring  42  causes the restraint panel  24  to immediately retract so that, as described above, the restraint panel  24  does not project into the aircraft aisle impeding egress from the aircraft. 
     The air bag  26  is mounted on and extends along the length of the restraint panel  24 . As is shown in  FIG. 5 , the air bag  26 , before deployment, resides in a deflated configuration against the restraint panel  24 . The air bag  26  includes a tubular neck  44  that is attached to an inflator  46  mounted on the cover  32 . In the deflated configuration, the neck  44  is folded in an accordion manner between the inflator  46  and the air bag  26 . The term “air bag” is generally used to describe this device even though gases other than “air” cause the bag to inflate. The inflator  46  may be a cold gas inflator, a hybrid inflator, or a pyrotechnic inflator depending on the design factors of the device. Speed, deployment time, gas temperature, etc. can all dictate the type of inflator  46  utilized to achieve the desired operation and may be the subject of varying legal and technical requirements. 
     The inflator  46  may be triggered by a trigger/sensor  48  that is also used to activate the seat belt  18 , see  FIG. 6 , or by a trigger/sensor that functions only to inflate the air bag  26 . As shown in  FIGS. 5 and 6 , the trigger/sensor  48  communicates with the inflator  46  through a shielded conduit  50 . As shown in  FIG. 6 , inflation of the air bag  26  causes the neck  44  to first inflate as gas passes from the inflator  46  to the air bag  26 . This inflation causes the neck  44  to unfold and straighten, driving the air bag  28  and the restraint panel  24  on which it is mounted rapidly forward out of the housing  22  and into the aisle of the aircraft, as shown in  FIGS. 3 and 4 . Typically, the air bag  26  is fully inflated within approximately 60-80 milliseconds, and vents in the air bag  26  allow the gas to escape, very rapidly deflating the air bag  26 . The spring  42  rapidly returns the restraint panel  24  and air bag  26  to the position shown in  FIG. 5 , as described above. 
     A leg restraint device for side-seated vehicle occupants according to the invention has been described with reference to specific embodiments and examples. Various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description of the preferred embodiments of the invention and best mode for practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation, the invention being defined by the claims.

Technology Classification (CPC): 1