Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
  • B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
  • B60N2/24—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles
  • B60N2/42—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats
  • B60N2/427—Seats or parts thereof displaced during a crash
  • B60N2/42727—Seats or parts thereof displaced during a crash involving substantially rigid displacement
  • B60N2/42736—Seats or parts thereof displaced during a crash involving substantially rigid displacement of the whole seat
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
  • B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
  • B60N2/24—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles
  • B60N2/42—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats
  • B60N2/4207—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats characterised by the direction of the g-forces
  • B60N2/4242—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats characterised by the direction of the g-forces vertical
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D11/00—Passenger or crew accommodation; Flight-deck installations not otherwise provided for
  • B64D11/06—Arrangements of seats, or adaptations or details specially adapted for aircraft seats
  • B64D11/0689—Arrangements of seats, or adaptations or details specially adapted for aircraft seats specially adapted for pilots
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D25/00—Emergency apparatus or devices, not otherwise provided for
  • B64D25/02—Supports or holding means for living bodies
  • B64D25/04—Seat modifications

Definitions

• the invention relates generally to crashworthy seats for a moving vehicle, in particular, to energy attenuat ⁇ ing crew seats for a helicopter.
• the energy attenuating system may include vertically ex ⁇ tending wires, affixed at opposite ends to the support structure and passing through a three-roller trolley at ⁇ tached to the seat.
• the wire is sized so that it will bend and unbend over the rollers, and allow the seat to move ' downward, or stroke, when a specified force acts upon the seat in a downward direction.
• This specified force is selected to be less than an inertia force act ⁇ ing upon the occupant of the seat during a crash of the helicopter which is likely to cause fatal damage to the occupant.
• the inertia force applied to the seats which is ecessary to cause stroking during a crash of the heli ⁇ copter is determined by multiplying the weight of the
• OMPI occupant and seat by the acceleration or G level since the specified force required to initiate stroking of the seat is a constant of the energy attenuation sys ⁇ tem, it is seen that a light-weight seat occupant will experience a higher G level than a heavy-weight seat oc ⁇ cupant. Also, for the same crash conditions, the seat will stroke a greater distance when occupied by a heavy ⁇ weight occupant than it will when occupied by a light ⁇ weight occupant.
• the specified force required to initiate stroking of the seat must be selected on the basis of the weight of the lightest occupant expected to use the seat, and the seat stroke distance must be se ⁇ lected on the basis of the weight of the heaviest occu ⁇ pant to use the seat.
• the G level experienced by a heavy seat occupant will"be much lower han that re'quired to protect him against fatal damage, and a seat will stroke through a much greater distance than would otherwise be required.
• I provide a crashworthy seat for a vehicle wherein the seat is con- nected to a support structure of the vehicle by an ad- justable energy attenuator which can be adjusted in • accordance to the weight of the seat occupant.
• a crashworthy helicopter crew seat includes a seat bucket which is slideably con ⁇ nected to a vertically extending support structure, which is in turn, slideably attached to the aircraft frame in the same manner as known helicopter crew seats.
• the back of the seat bucket is connected to the vertical support frame through an adjustable energy attenuator which can be adjusted in predetermined steps by an ad ⁇ justment mechanism mounted to the support structure.
• the adjustable energy attenuator includes a wire sup ⁇ port frame to which the seat bucket is slideably mounted and locked thereto by a locking pin, so that the seat can be adjusted vertically with respect to said wire support frame.
• At least three sets of parallel arranged wires extend between top and bottom members of the wire support frame through a trolley carried by the seat sup ⁇ port member.
• the trolley includes three wire .bending assemblies, one for each set of wires.
• Each wire bending assembly includes three vertically spaced, horizontally extending parallel rod members.
• the three sets of wires are bent about one side of the top rod members, the opposite side of the intermediate rod members, and about the same One side of the bottom rod members, so that during strok ⁇ ing of the seat, all of the wires bend and unbend as the seat bucket strokes downward.
• the axes of all of the rod members are fixed relative to the trolley structure to which they are connected.
• the three top rod members may be pivotally carried by the trolley structure for rota ⁇ tion about their axes, and, may be connected together as a single common rod.
• the middle and bottom rod members of the first wire bending assembly may also be pivotally connected to the trolley structure for rotation about their axes.
• the middle and bottom rod members of a sec ⁇ ond wire bending assembly disposed on one side of the first wire bending assembly are slideably carried by the trolley structure for axial movement between a first po ⁇ sition in which these rollers engage a second set of the wires and a second position at which these rod members are disengaged from the second set of wires.
• the middle and bottom rod members of this second wire bending as ⁇ sembly are connected with each other and to attenuator adjustment mechanism.
• the middle and bottom rod members of the third wire bending assembly which is disposed on the opposite side of the first wire bending assembly, are also carried by the trolley structure for axial movement along their axes between the first position at which they are engaged with the third set of wires, and a second position at which they are disengaged from the third set of wires.
• the middle and bottom rod members of this third wire bending assembly are also connected with each other and with the energy attenuator adjustment mecha ⁇ nism.
• the first wire bending assembly of the trolley is always engaged with the first set of wires, and thus de ⁇ termines the minimum engagement setting of the energy attenuator, at which the middle and bottom rod members of the second and third wire bending assemblies are dis- -posed in their disengaged positions.
• the middle and bottom rod mem ⁇ bers of the second wire bending assembly are moved along " their axes to their engaged positions, so that the first and second sets of wires are engaged with the first and second wire bending assemblies, respectfully.
• the middle and bottom rod members of the third wire bending assembly are moved axially into their first position to engage the third set of wires.
• Figure 1 is a side view of a crashworthy crew seat for a helicopter, according to the invention
• Figure 2 is a vertical view of the crew seat shown in Figure 1, with the bucket seat removed from its back support frame mem ⁇ bers
• Figure 3 is a cross-sectional view of the seat structure shown in Figure 2, taken along the line 3-3 of Figure 2
• Figure 4 is an other cross-sectiorial view of the seat structure shown in Figure 2, taken generally along the line 4-4 of Figure 2
• Figure 5 is an enlarged view of the energy attenuator trolley shown in Figure 2
• Figure 6 is a vertical cross-sectional view of the trol ⁇ ley assembly shown in Figure 5, taken along the line 6-6 of Figure 5
• Figure 7 is a back vertical view of the en- ergy attenuator adjustment mechanism, shown in Figure 4; taken along the line 7-7 of Figure 4
• Figure 8 shows per ⁇ formance curves of acceleration and stroke distance ver ⁇ sus the weight of the seat and seat occupant for maximum, intermediate, and minimum settings of the adjustable en
• the crashworthy helicopter crew seat assembly 10 shown in Figure 1 includes a seat bucket 12 having a back portion affixed to two support brackets 14 and 16.
• the seat bucket 12 is held in rolling contact with a support structure 18 by a set of four rollers 20, 22, 24, 26, carried by each of the support brackets 14, 16, which are engaged in rolling contact with four vertically extend ⁇ ing track surfaces 28, 30, 32, 34, of the support struc ⁇ ture 18, respectively, as seen in Figures 3 and 4.
• the support structure 18 includes a diagonal member 36 which is connected to a generally horizontal member 38 and is held in rolling contact with a horizontal track member 40 affixed to the floor of the aircraft, to allow hori ⁇ zontal movement of the seat bucket 12 along the track member 40.
• the support structure 18 also includes a locking mechanism 42 for securing the support structure 18 to the floor of the aircraft at selected intervals along the horizontal track 40.
• an energy attenuating assembly 44 is connected between the seat support brackets 14, 16 and the support structure 18, to prevent movement of the seat bucket 12 with respect to the support structure 18 during normal operation of the aircraft.
• An energy at ⁇ tenuator support frame 46 includes top and bottom wire support members 48, 50, which are connected at each end to two side support rods 52, 54, which extend through openings 56, 58 in the upper support bracket 14 of the seat bucket 12.
• a vertically extending rod 60 having a series of vertically-spaced, diametrical holes 62 drilled therethrough, is affixed at its upper end to a center portion of the bottom wire support member 50.
• the rod 50 is telescopically received by, and extends through, a center opening in the lower support bracket 16 of the seat bucket 12.
• a spring actuated lock pin 64 which is slidably supported within , the lower support bracket 16 and is connected to a seat height adjustment mechanism 66, extends into a selected one of the diametrical holes 62 to lock the seat bucket 12 to the energy attenuator support frame 46.
• Three attenuation wires 68, 70, 72 have mid-points which are affixed to the bottom wire sup ⁇ port member 50, and parallel-disposed opposite end por ⁇ tions which extend through a roller trolley assembly 74 to the top wire support member 48, to which the ends of the three wires 68, 70, 72 are affixed.
• the trolley assembly 74 includes a mounting plate 76 which is affixed to the support structure 18 and which includes four vertical plates 78, 80, 82, 84 extending into the support frame 46 on either side, and in between, the three wires 68, 70, 72.
• Each of the vertical plates 78, 80, 82, 84 have three circular openings therethrough for supporting rol ⁇ lers or rods disposed or inserted therein along three. vertically spaced, horizontal axes A-A, B-B, C-C.
• a top roller member 86 extends through the top openings of the vertical plates 78, 80, 82, 84 and is rotatably mounted therein for rotation about the axis A-A.
• An intermediate roller member 88 extends through the intermediate holes of the vertical plates 80, 82, and is rotatably mounted therein for rotation about the axis B-B.
• a bottom roller member 90 extends through the bottom holes of the plates 80, 82, and is rotatably mounted therein for rotation about the axis C-C.
• the mounting plate 76 includes two vertically disposed end plates 92, 94, each containing two openings aligned with the intermediate and bottom openings through the plates 78, 80, 82, 84, respectively.
• a first intermediate rod assembly 96 ex- tends through the intermediate openings of the vertical plates 92, 78, and is slideably mounted therein for translation along the axis B-B between a disengaged posi ⁇ tion, shown in Figure 4, and an engaged position, shown in Figure 2.
• a second intermediate rod assem- bly 98 extends through the intermediate openings of the vertical plates 84, 94, and are slideably mounted there ⁇ in for translation along the axis B-B.
• a first bottom rod assembly 100 extends through the bottom openings of the vertical plates 92, 78, and are slideably mounted therein for translation along the axis C-C between an engaged position and a disengaged posi ⁇ tion.
• a second bottom rod assembly 102 ex ⁇ tends through the bottom openings of the vertical plates 84, 94, and is slideably mounted therein for translation along the axis C-C.
• the first and second intermediate rod assemblies 96 are identical to each other.
• » 98 include first and second intermediate rod members 104,
• first and second bottom rod assemblies 100, 102 include first and second bottom rod members 112, 114, and first and second bottom rollers, 116, 118, which are rotatably mounted to the inner ends of the first and second bottom rod members 112, 114, re ⁇ spectively, for rotation about the axis C-C.
• the first intermediate and bottom rod assemblies 96, 100 are connected together for tandem operation by a first connecting pin 120 extending diametrically through the first intermediate and bottom members 104, 112.
• the second intermediate and bottom rod assemblies 98, 102 are connected together for tandem operation by a second connecting pin 122 which extends diametrically through the second intermediate and bottom members 106, 114.
• both end portions of the wire 72 are bent about the top roller member 86, the second intermediate roller 110, and the second bottom roller 118, in the same manner as shown for the wire 70 in Figure 6.
• the energy attenuator assembly 44 is initially assembled with all four rod assemblies 96, 98, 100, 102, disposed in their engaged positions.
• the two bent portions of the attenuation wire 70 which are always engaged with the roller members 86, 88, 90, prevent movement, with respect to the support struc ⁇ ture 18, of the energy attenuator support frame 46 and the seat bucket 12 which is affixed to the frame 46 by the lock pin 64, during normal operation of the aircraft.
• the height of the seat bucket 12 can be adjusted by the Seat occupant by withdrawing the lock pin 64, mov ⁇ ing the seat bucket 12 to the desired height, then rein- serting the lock pin 64 in the closest adjacent hole 62 of the rod 60.
• the energy attenuator support frame 46 may include two helical springs 124, 125, disposed about the side support rods 52, 54, respectively, which exert a force between the bottom wire support member 50 of the frame 46 and the upper support bracket 14 of the seat bucket 12, to counterbalance the weight of the seat buc ⁇ ket 12 so that it can be easily adjusted to the desired height.
• These helical springs 124, 126 can also be used to to prevent the seat bucket 12 from being lowered be- yond the position at which the lock pin 64 engages the lowest one of the holes 62.
• the adjustment mechanism 126 includes a manual operating lever 128 having one end affixed to an operating shaft 130 which is pivotally carried by the upport structure 18 for rotation about the operating shaft axis.
• a manual operating handle 132 which is slideably carried by the other end of the operating lever 128 for radial movement towards to away from the operat ⁇ ing shaft 130, is spring-loaded in the direction of the operating shaft 130 to hold a handle positioning pin 134, affixed to the handle 132, against the periphery of a circular handle positioning plate 136 affixed to the sup ⁇ port structure 18 and disposed concentrically about the operating shaft 130.
• the periphery of the positioning .plate 136 defines three indents 138, 140, 142, corre- sponding to maximum, intermediate, and minimum engaged positions of the energy attenuator assembly. 44, respec ⁇ tively.
• the positioning, pin 134 is dis ⁇ posed within the indent 142 (not shown) corresponding to the minimum engagement position of the energy attenuator assembly 44.
• a bell crank 144 which is affixed to -the operating shaft 130, has a first arm 146 pivotally connected to one end of a first connecting link 148, and a second arm 150 pivotally connected to one end of a second connect- ing link 152.
• the other end of the first connecting link 148 is pivotally connected to one end of the first lever 154 which is pivotally connected to the support member 18 by a first pivot pin 156 for rotation about an axis substantially orthogonal to the axes A-A, B-B, and C-C.
• the opposite end of the second connecting link 152 is pivotally connected to one end of a second lever 158 which is pivotally connected to the support structure 18 by a second pivot pin 160 for rotation about an axis sub ⁇ stantially orthogonal to the axes A-A, B-B, or C-C.
• the opposite end of the first lever 154 includes a first elongated opening or slot 162 therethrough, which extends radially of the first pivot pin 156; similarly, the sec ⁇ ond lever 158 includes a second slot 164 therethrough, which extends radially of the second pivot pin 160.
• the first connecting pin 120 connecting the first intermediate and bottom rod assem ⁇ blies 96, 100 extends through the first slot 162 be ⁇ tween the rod assemblies 96, 100; similarly, the second connecting pin 122 connecting the second intermediate and bottom rod assemblies 98, 102, extends through the second slot 164 between the rod assemblies 98, 102.
• the first bell crank arm 146 will be rotated counter-clockwise to move the first intermediate and bottom rod assemblies 96, 100 to their fully engaged positions at which the attenuator wire 68 engages the top roller member 86, a second inter ⁇ mediate roller 108, and the second bottom roller 116.
• the further counter-clockwise movement of the second bell crank arm 150 from its intermediate position to its fully engaged position merely rotates the second bell crank arm 150 over its toggle point, during which the second intermediate and bottom rod assemblies 98, 102, remain fully engaged with the attenuator wire 72. Since the second intermediate and bottom rod assemblies 98, 102, do move slightly inwardly to a maximum position at the toggle point of the bell crank second arm 150, the ends of -the intermediate and bottom roller members 88, 90, adjacent the second intermediate and bottom rollers
• OMPI 110, 118 may be recessed to receive a second inter ⁇ mediate and bottom rollers 110, 118, as these rollers 110, 118, are moved from their fully engaged position to their maximum position at the toggle point of the second bell crank arm 150 and back again to their full engaged position, so that the second intermediate and bottom rol ⁇ lers 110, 118, engage with the intermediate and bottom roller members 88, 90, when the operating handle 132 is disposed in both its intermediate and fully engaged posi- tions.
• Figure 8 shows typical minimum, intermediate and max ⁇ imum engagement performance curves of acceleration force, in G units and the seat stroke, in inches, versus the weight of the seat occupant, including all clothing and/ or protective equipment worn by the occupant, for the energy attenuator assembly 44 of the seat assembly 10 when the seat assembly 10 is subjected to a 48G peak pulse of .054 seconds duration.
• Curve A corresponds to the minimum engagement setting of the attenuator assembly 44, in which the attenuator wire 70 is sized to initiate stroking of the seat bucket 12 when a downward acting force of approximately 3500 lbs. is applied to the seat bucket 12.
• Curve B corresponds to the intermediate en ⁇ gagement setting of the energy attenuator assembly 44, in which energy attenuator wire 72 is sized so that when the wires 70 and 72 are engaged, the seat bucket 12 will begin to stroke when the force acting downward upon it equals approximately 4100 lbs.
• Curve C corresponds to the fully engaged setting of the energy attenuator assem ⁇ bly 44, in which the attenuator wire 68 is sized so that when all of the attenuator wires 68, 70, 72, are engaged, a downward acting force of approximately 5000 lbs. must be applied to the seat bucket 12 to initiate stroking.
• the energy attenuator assembly 44 When the energy attenuator assembly 44 is set at its minimum engaged position, the acceleration force acting on the seat occupant will not exceed 22G, and the seat stroke will not exceed 7 inches, so long as the verti ⁇ cally effective weight of the seat bucket 12 and the fully clothed seat occupant falls within the range of 157 to 191 lbs.
• the energy attenuator assembly 44 When the energy attenuator assembly 44 is set at its int4rmediate engagement position, the maximum acceleration force exerted on a seat occupant will be limited to 22G and the maximum stroke of the seat bucket 12 will be limited to 7 inches so long as the vertically effective weight of the seat bucket 12 and the occupant therein falls with the range of 187 to 228 lbs.
• Figures 9 and 10 illustrate an energy attenuator assembly 44' simi- lar to the energy attenuator assembly 44 described above and having its elements numbered the same as correspond- ing elements of the energy attenuator assembly 44.
• the trolley mounting plate 76* is similar to the mounting plate 76 described above except that it includes two ad- ditional vertical plates 166, 168, extending between the two portions of the attenuator wires 68 and 72, respec ⁇ tively.
• the attenuator adjustment mechanism 126' is similar to the above described * attenuator adjustment mechanism 126, except that it includes a vertically ex- tending operating shaft 130' having a bell crank 144 ' affixed to its lower end and extending to a spring loaded manual operating handle assembly 170 which is function ⁇ ally similar to the manual operating lever assembly 128 described above except having three intermediate settings between a minimum and a maximum engagement setting, rather than only one.
• the bell crank 144' is connected to operate the first and second levers 154, 158, by first and second connecting links 148', 152' similar to first and second connecting links 148, 152 described above.
• OMPI handle is further rotated in a clockwise direction to a second intermediate setting, the second intermediate and bottom rod assemblies are moved axially inward to engage the other portion of the attenuation wire 72 disposed between the vertical plates 82 and 68.
• the second intermediate and bottom rod assemblies 98, 102 remain engaged with both portions of the wire 72, and the first intermediate and bottom assemblies 96, 100 are moved axially inward and engage the portion of the attenuation wire 68 disposed between the vertical plates 78 and 166.
• a first intermediate and bottom rod assemblies 96, 100 are further moved axially inward to engage the other portion of the wire 68 disposed between , the vertical plates 168 and 80.
• the additional inter- mediate settings of the energy attenuator assembly 44' either allow the maximum stroking distance to be further reduced, or allow a wider range in the weight of the seat occupant or allow the size of the wires 68, 70, 72 to be reduced to lower the maximum acceleration force for the seat occupant.
• first and second intermediate rod assemblies 96, 98 can be moved in a forward direction towards the seat bucket 12, and the first and second bottom rod assemblies 100, 102, can be moved in opposite backward direction towards the support structure 18, rather than moving these rod assemblies 96, 98, 100, 102, along their axes.
• this is not a preferred embodiment of the invention in that the seat bucket 12 must be spaced much further from the support structure 18 than it is in the above described preferred embodiment.
• the first and second bottom rod assemblies 100, 102 can be omitted.
• this is disadvantageous in that, for the same size attenuation wires, the force at which stroking of the seat is initiated is reduced to one-half or less than the force of a three roller wire bending trolley assemblies, as described above.
• the support structure 18 is integrally affixed to a vertical bulk ⁇ head of the aircraft to allow the seat bucket 12 to stroke downward along a vertical path in the event of a ' crash. .

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• Engineering & Computer Science (AREA)
• Aviation & Aerospace Engineering (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Seats For Vehicles (AREA)

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Publications (1)

Family

ID=22796193

Family Applications (1)

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Cited By (1)

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Citations (8)

Family Cites Families (5)

• 1980
  • 1980-12-05 US US06/213,709 patent/US4358154A/en not_active Expired - Lifetime
• 1981
  • 1981-12-04 IT IT12697/81A patent/IT1205451B/it active
  • 1981-12-07 WO PCT/US1981/001625 patent/WO1982001854A1/en active IP Right Grant
  • 1981-12-07 GB GB8222157A patent/GB2099295B/en not_active Expired
  • 1981-12-07 DE DE813152570T patent/DE3152570T1/de active Granted
  • 1981-12-07 EP EP82900240A patent/EP0065982B1/en not_active Expired

Patent Citations (8)

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