The following disclosure relates generally to aircraft occupant restraint systems, and more particularly to aircraft occupant restraint systems having pretensioning devices and associated systems and methods.
Commercial aircraft seats typically include two-point restraint systems to secure occupants. Unlike three- and four-point restraints, conventional two-point restraints may not restrict forward movement of the occupant's head toward a forward structure. Several conventional two-point restraints seek to address this problem, such as by use of webbing with low-elongation properties. However, low-elongation webbing only limits head excursion a small amount and can cause high contact loading over a short time period (e.g., immediate deceleration of the occupant against the webbing). Another conventional restraint system that seeks to limit head excursion is a “Y-belt restraint.” A Y-belt restraint utilizes an additional attachment element that raises the height of the seatbelt on the occupant's torso and consequently raises the rotation point of the occupant about the seatbelt. Y-belt restraints, however, may also have disadvantages. First, the additional attachment element requires additional attachment points on the seat structure and additional reinforcement elements to support the additional attachment points. This additional structure increases seat weight and complexity. Second, Y-belt restraints are generally uncomfortable for the occupant. Third, the Y-belt restraint can position the belt at a location that is up and away from the pelvic region of the occupant. During a dynamic event (e.g., a rapid deceleration and/or acceleration, collisions, impacts, etc.) the occupant's body is loaded and point-restrained at the belt contact area which is misaligned with the protective skeletal structure of the pelvic region.
The present disclosure describes various embodiments of aircraft occupant restraint systems having pretensioning systems. Although embodiments of the present technology are described herein in the context of airplane occupant restraint systems (e.g., commercial airline occupant restraint systems), those of ordinary skill in the art will understand that the various apparatuses, systems and methods described herein can also be used in other types of vehicles, such as other types of aircraft (e.g., helicopters, etc.). Accordingly, aspects and embodiments of the present disclosure are not limited to use in airplanes. In the following description, numerous specific details are discussed to provide a thorough and enabling description for embodiments of the technology. One skilled in the relevant art, however, will recognize that the disclosure can be practiced without one or more of the specific details. In other instances, well-known structures or operations often associated with occupant restraint systems are not shown, or are not described in detail, to avoid obscuring aspects of the technology. In general, alternatives and alternate embodiments described herein are substantially similar to the previously described embodiments, and common elements are identified by the same reference numbers.
In the illustrated embodiment, the restraint 130 includes a web or belt 132 configured to extend across the occupant's lap. As used herein, a “web” can include any type of flexible strap or belt, such as a seat belt made from woven material (e.g., woven nylon) as is known in the art for use with personal restraint systems. The web 132 can include flexible segments of a fixed length and/or adjustable length to accommodate different sized occupants. For example, in the illustrated embodiment, the web 132 includes a first web portion 133 and a second web portion 135. The distal ends of the first and second web portions 133, 135 can be releasably coupled together by a coupler 134 (e.g., a “lift-latch” buckle, a “press-release” buckle, etc.). A proximal end of the first web portion 133 can be coupled to the pretensioner 100, and a proximal end of the second web portion 135 can be coupled to an anchor point on the aircraft 16 (or a structure thereof) at a location that is opposite the side of the seat 12 where the pretensioner 100 is positioned. In the illustrated embodiment, for example, the proximal end of the second web portion 135 is coupled to a web retractor 160 (e.g., an inertial reel) fixed to the seat 12 and/or to an anchor point on the aircraft 16. The web retractor 160 is configured to automatically adjust the fit of the web 132 in response to movement of the occupant 14 and/or the aircraft 16 in a conventional manner. In other embodiments, the proximal end of the second web portion 135 can be fixed directly to the seat 12 or associated structure (e.g., the seat frame) and/or the web 132 can be manually adjustable, static, etc. Although only one pretensioner 100 is shown in
The sensor assembly 170 can include one or more sensors 174 (e.g., acceleration sensors, accelerometers, etc.) configured to sense acceleration and/or deceleration events above a preset magnitude (e.g., above 9 g's, where “g” refers to gravitational force or “g-force”) in one or more directions and send associated control signals to the pretensioner 100 via the link 172. For example, the sensor assembly 170 can include at least one acceleration sensor configured to sense vehicle accelerations in the vertical direction along a Z axis and one or more additional sensors configured to sense accelerations in the fore and aft directions along a X axis and/or laterally along a Y axis. In other embodiments, the sensor assembly 170 can include different sensor arrangements features and/or have a different number of acceleration and/or deceleration sensors. Other suitable sensor assemblies for use with the occupant restraint system 10, for example, can be found in, for example, U.S. Pat. No. 8,303,043, which is incorporated herein by reference in its entirety.
In the illustrated embodiment, the pretensioner 100 is configured to be attached to the seat 12 (e.g., a seat frame 18) and/or the aircraft 16. In some embodiments, the pretensioner 100 can take the place of a traditional seatbelt mount and can be mounted at or near a traditional seatbelt mounting location. For example, in some embodiments, the pretensioner 100 can be attached to a frame 18 (
Although the pretensioner 100 of the illustrated embodiments is shown fixed to a side portion of the seat 12, it will be appreciated that in some embodiments, the pretensioner 100 can be positioned at different locations in the aircraft 16, such as at a rear portion of the seat 12, so long as the tensioning angle θ is maintained as described above.
The cable 106 is operably coupled between the web 132 and the piston 110, with the second cable portion 109 being fixedly coupled to the web 132 via the connector 107 and the first cable portion 111 being fixedly coupled to the piston 110 within the interior portion 103 of the housing 104. In this embodiment, a mid-portion of the cable 106 can contact and curve around the pulley 114.
The activator 102 can be a gas generator 112 (shown schematically) fitted in a socket 113 formed on the housing 104 in fluid communication with a portion 116 of the tube interior 103. The gas generator 112 can be a pyrotechnic element (e.g., an initiator, etc.) as is known in the art and can be activated by an electrical signal generated by the sensor assembly 170 (
In operation, when the sensor(s) 174 of the sensor assembly 170 sense an aircraft acceleration and/or deceleration above a preset magnitude, the sensor assembly 170 sends a corresponding electrical signal to the activator 102 via the link 172. The activator 102 responds to the signal by activating the gas generator 112. The generator 112 then generates combustion gases which increase the pressure within a portion 116 of the tube 105. As the pressure inside the tube 105 increases on one side of the piston 110, it drives the piston 110 to the right (as indicated by arrow A) thereby pulling the cable 106 into the housing 104. As the second cable portion 109 is retracted into the tube 105, it pulls the web 132 downwardly and aft at the tensioning angle θ, as described above with reference to
In some embodiments, the pretensioner 100 can be load-limiting. In other words, in some embodiments, the pretensioner 100 can be configured to stop retracting the cable 106 (and thus cease pulling on the web 132) when a tension load on the web 132 (exerted by the occupant) reaches a preset force magnitude. For example, in some embodiments, the preset force can be between about 430 lbs. and about 530 lbs., or between about 460 lbs. and about 500 lbs. In a particular embodiment, the preset force magnitude can be about 480 lbs. Moreover, in some embodiments the pretensioner 100 can be configured to sustain an applied load of at least 3,000 lbs. both before and after retraction of the cable 106. In other embodiments, the pretensioner 100 can be configured to hold other loads.
In other embodiments, the occupant restraint system 10 configured in accordance with the present technology can include other types of pretensioners. Such pretensioners can include, for example, other suitable electrical, mechanical, pneumatic, hydraulic, and/or electromechanical pretensioning devices.
In operation, in response to a dynamic event above a preset magnitude, the sensor assembly 170 sends an electrical signal to the activator 402 via the link 172. The activator 402 then activates the gas generator. Upon activation of the generator, combustion gases are generated which increase the pressure within the tube 405 on the upstream side of the piston 410. As the pressure inside the tube 405 increases on one side of the piston 410, it drives the piston 410 through the tube 405 (as indicated by arrow A) thereby retracting the cable 406. As the cable 406 retracts, the cable 406 rotates the second spool 423, thereby rotating the first spool 422 and retracting the web 132 in the direction A as described above with references to
In other embodiments, the occupant restraint system 10 can include different features and/or have different configurations. For example, although the occupant restraint system 10 illustrated in
The restraint 530 can be configured to be coupled to an aircraft seat (shown schematically) and/or an aircraft cabin structure (not shown) at a first attachment point A1 positioned at a proximal end of the first web portion 533, a second attachment point A2 positioned at a proximal end of the second web portion 535, and a third attachment point A3 positioned at a proximal end of the third web portion 537.
In the illustrated embodiment, the restraint 530 includes a pretensioner 500 coupled to the proximal end portion of the second web portion 535. The pretensioner 500 can be any of the pretensioners described herein. In other embodiments, more than one pretensioner 500 can be coupled to the restraint 530 and/or the pretensioner 500 can be coupled to the first and/or third portions 533, 537.
From the foregoing, it will be appreciated that specific embodiments have been described herein for purposes of illustration, but that various modifications may be made without deviating from the spirit and scope of the various embodiments of the disclosure. For example, the occupant restraint systems described above with reference to
This application claims the benefit of U.S. Provisional Patent Application No. 61/913,872, filed Dec. 9, 2013, which is incorporated by reference herein in its entirety.
Number | Date | Country | |
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61913872 | Dec 2013 | US |