Aircraft seat with a single-beam structure and aircraft comprising such a seat

Abstract

An aircraft seat includes a seat bucket that is integral by its seatback with a single beam oriented along an axis that is approximately perpendicular to the aircraft floor, which beam is integral with fastening points located on at least two separate lines on the aircraft floor.

Claims

1. Aircraft seat comprising: a seat bucket (1), which establishes a longitudinal direction X forward of the seat and a vertical direction Z above the seat, said seat bucket comprising a seatback (3) and a seat pan (2) integral with said seatback, and a single structural guide beam (5), located in a rear part of the seat, oriented in an approximately vertical or inclined direction Z1 in relation to the vertical direction Z in a plane XZ determined by the longitudinal direction X and vertical direction Z, on which said guide beam the seat bucket (1) is fastened, said guide beam (5) being integral with a connecting structure for connecting said guide beam to a floor (100) of an aircraft, said connecting structure comprising, at least four fastening points, for fastening to said floor, distributed along two lines that are approximately parallel to the longitudinal direction X and that are apart from a vertical plane of symmetry XZ of said seat, and a mounting sleeve (6) of the guide beam (5) and with which sleeve four feet (8a, 8b, 9a, 9b) are integral and at the free ends of the four feet the fastening points are placed.

2. Aircraft seat according to claim 1, wherein the seat bucket (1) is held in front of the guide beam (5) by two attachment parts (10, 11) that are integral with the seatback (3) on a rear face of said seatback and apart from one another in the direction Z1.

3. Aircraft seat according to claim 2, wherein the two attachment parts (10, 11) that are integral with the seatback (3) slide along the guide beam (5) in the direction Z1 and comprise a device for locking the position in the direction Z1 of at least one of said two attachment parts.

4. Aircraft seat according to claim 3, wherein two of the four feet (8b, 9b) of a same line of fasteners that is approximately parallel to the direction X of the connecting structure are rigidly connected to the guide beam (5) and wherein another two of the four feet (8a, 9a), rigidly integral with one another, of another line of fasteners are fixed in an articulated manner, along an axis Y oriented perpendicularly to the plane XZ, in relation to a sub-unit formed by the guide beam (5) and the two feet (8b, 9b) that are rigidly connected to said guide beam.

5. Aircraft seat according to claim 4, wherein the two feet (8b, 9b) of the same line of fasteners that are approximately parallel to the direction X of the connecting structure rigidly linked to the guide beam (5) are linked by means of an articulation around the axis Y, said articulation comprising a device for locking in rotation.

6. Seat according to claim 5, wherein two of the four feet (8a, 9a) (8b, 9b) of a same line of fasteners that is approximately parallel to the direction X comprise a stationary part (8a, 8b), provided with an interface for a fastening point on the floor (100) that is integral with the guide beam (5), and an adjustable part (9a, 9b), also provided with an interface for a fastening point, the adjustable part (9a, 9b) being integral with the stationary part (8a, 8b) and being able to slide in relation to the stationary part (8a, 8b) in a direction X that is parallel to the lines of fastening points, with at least one space between two floor (100) fastening points or that can be changed in length in the direction X.

7. Aircraft seat according to claim 4, wherein the two feet (8a, 9a) (8b, 9b) of the same line of fasteners that is approximately parallel to the direction X comprise a stationary part (8a, 8b), provided with an interface for a fastening point on the floor (100) that is integral with the guide beam (5), and an adjustable part (9a, 9b), also provided with an interface for a fastening point, the adjustable part (9a, 9b) being integral with the stationary part (8a, 8b) and being able to slide in relation to the stationary part (8a, 8b) in a direction X that is parallel to the lines of fastening points, with at least one space between two floor (100) fastening points or that can be changed in length in the direction X.

8. Aircraft seat according to claim 4, further comprising a safety belt that is integral with the seat bucket 1, said safety belt having a free length on an interior side of the bucket that is a function of morphological characteristics of a passenger and in which said belt from each fastening point of the belt to the bucket passes through a first guide (14a, 14b) that is integral with the guide beam (5), located at a height greater than the attachment to the bucket, then passes through a second guide (15a, 15b) that is integral with a foot of the corresponding side (8a, 8b), located at a height lower than the first guide and at a height lower than the seat pan (2), and then rises above the seat pan.

9. Aircraft seat according to claim 2, wherein the structure for connecting the guide beam (5) to the floor (100) comprises a mounting sleeve (6) of the guide beam (5) and with which sleeve four feet (8a, 8b, 9a, 9b) are integral and at the free ends of which feet the fastening points are placed.

10. Aircraft seat according to claim 1, wherein the guide beam (5) slides in a direction parallel to Z1 in the sleeve (6) and is held in the direction of sliding by a damping device with an approximately vertical axis.

11. Aircraft seat according to claim 10, wherein the feet (8a, 8b, 9a, 9b) are placed to absorb, by deformation, energy linked to a force, a vertical component downward of which exceeds a predefined threshold.

12. Aircraft seat according to claim 1, wherein the four feet (8a, 8b, 9a, 9b) are placed to absorb, by deformation, energy linked to a force, a vertical component downward of which exceeds a predefined threshold.

13. Aircraft seat according to claim 1, wherein one of the two attachment parts (10) (11) that are integral with the seatback (3) comprises a pivot pin (111) for articulation of the seatback around an axis parallel to a direction Y that is perpendicular to the plane XZ, and the other attachment part (11) (10) comprises an extendable part (101) for locally changing a distance from said seatback to the guide beam (5).

14. Aircraft seat according to claim 13, wherein the guide beam (5) comprises at least two slides (51a) that are approximately symmetrical in relation to a vertical symmetry plane XZ of said guide beam in which slides the attachment parts (10, 11) that are integral with the seatback (3) are mounted to slide freely.

15. Aircraft seat according to claim 14, wherein the attachment part comprising an extendable element comprises at least two arms (112a, 112b) sliding in an anterior slide (51a) at independent ends and pivoting around a common axis parallel to the direction Y linked to the seatback (3) at other ends of said at least two arms to form an angle that can be changed.

16. Aircraft seat according to claim 1, wherein the guide beam (5) comprises a fastener in an upper part of said guide beam for connection to a ceiling structure or to a structure of a bulkhead of an aircraft.

17. Aircraft comprising at least one aircraft seat according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The description and the drawings of a particular embodiment of the invention will make it possible to better understand the aims and advantages of the invention. It is clear that this description is given by way of example and has no limiting character.

(2) In the drawings:

(3) FIG. 1 illustrates diagrammatically a column-type seat, known to a person skilled in the art, seen from the side;

(4) FIGS. 2 and 3 illustrate in the same way seats of the parallelogram type;

(5) FIG. 4 illustrates in the same way a seat of the pantograph type;

(6) FIG. 5 illustrates in the same way a console-type seat;

(7) FIG. 6 illustrates in a simplified way in perspective an aircraft seat according to the invention, as seen from the rear;

(8) FIGS. 7a, 7b, 7c, 7d, 7e, 7f illustrate a particular embodiment of the invention, respectively in perspective as seen from the left rear (FIG. 7a), in view from the rear (FIG. 7b), in perspective view from the front (FIG. 7c), in left view for two seat-height positions (FIG. 7d), a view of an example of a guide beam in a straight cross-section (FIG. 7e), and a rear perspective detail of the seat of the belt device (FIG. 7f);

(9) FIG. 8 illustrates, seen from the rear in perspective, another example of an embodiment of a seat according to the invention comprising an articulated foot and a device for adjustment of inclination of the bucket.

DESCRIPTION OF PREFERRED EMBODIMENTS

(10) A seat according to the invention finds its place in an aircraft, oriented along a longitudinal axis of the aircraft, approximately facing or backing against a principal direction of movement of the aircraft during flight, fastened to a floor 100 on which are present one or more groups of two fastening tracks 110a, 110b that are parallel to one another and to the longitudinal axis of the aircraft, intended for the fastening of seats, or at least one set of seat-fastening points.

(11) The seat is a seat for a pilot, fastened in a pilot compartment, or for a passenger, fastened in a cabin, of the aircraft.

(12) Considered in this description are two tracks of fasteners, intended for the fastening of a seat, the spacing and characteristics of which are known to a person skilled in the art, and are therefore not described in detail here. In the description below, a reference X, Y, Z will be used for the longitudinal, transverse and vertical axes of the seat. Likewise, along the longitudinal axis X, the terms forward and rear, corresponding to the direction of the seat, will be used, and in an equivalent manner, the terms anterior and posterior.

(13) Each of these tracks 110a, 110b comprises fastening sites, not explained in detail in the figures, which make it possible to attach a structure on these tracks, typically by bolting, these fastening sites being generally regularly spaced, with a standard spacing span, for example one inch.

(14) As can be seen in FIG. 6, intended to understand the principle of the invention more than to show the dimensions of the various elements, an aircraft seat conventionally comprises a seat bucket 1 composed of a seat pan 2, a seatback 3, armrests 4 and a headrest 31. The seat bucket 1, certain parts of which are optional (armrests, headrest, . . . ) and optionally articulated to one another for ergonomic adjustments needs, is of conventional shape and material in this field, for example made of metallic materials or of composite materials, and not explained in detail here. In a known way, the seat is oriented, at least during the takeoff and landing phases, along the longitudinal axis of the aircraft, taking into account accelerations undergone by the occupant of the seat during accelerations that can be encountered during an emergency braking or during a crash.

(15) According to the invention, the seat bucket 1 is fastened by the seatback 3 by a rear part of the seatback to a guide beam 5 that is a structural beam.

(16) The guide beam 5, located preferably near a vertical symmetry plane X, Z of the seat, extends generally parallel to a center line of the seatback 3, and therefore approximately perpendicularly to the floor 100, optionally slightly inclined from bottom to top toward the rear of the seat 1, along an angle of inclination of about twenty degrees in this example, along a main axis Z1.

(17) The angle of inclination, advantageously between zero and twenty-five degrees toward the rear, is advantageously adapted as a function of the possible adjustments on the seat so as to simplify these other adjustments.

(18) The fastening of the seatback 3 on the guide beam 5 is achieved by lower 10 and upper 11 attachment means that make it possible for said attachment means to slide along the guide beam 5, and thereby to change a position of the seat bucket 1 in a direction Z1 in relation to the floor 100 to make possible a height adjustment of said seat bucket, the height adjustment having a simultaneous effect on the longitudinal position of the seat bucket when the guide beam 5 is inclined in relation to the vertical. Types of height position adjustment means are known, for example in the case of column-type seats having two lateral beams, and are outside the scope of this invention.

(19) In one embodiment, the upper attachment means 11 comprises, as illustrated in FIG. 6, a pivot pin 111 making possible a rotation of the seat bucket 1 in relation to the guide beam 5 around said pivot pin with an orientation parallel to the transverse axis Y. In this embodiment, the lower attachment means 10 comprises, on the one hand, an extendable device, such as a jack, for changing within certain limits the distance from a point of the seat bucket 1 in relation to the guide beam 5 and, on the other hand, a catch to hold said distance, the whole forming an inclination device 101 that makes possible the inclination adjustment of the seat bucket 1 by pivoting around the pivot pin 111.

(20) In one embodiment, not shown, an equivalent result for obtaining an inclination of the seat bucket 1 consists in using a reverse arrangement in which the lower attachment means is just pivoting, and the upper attachment means makes it possible to change the distance from a point of the seat bucket to the guide beam.

(21) The guide beam 5, in this nonlimiting example, has a length that is close to the height of the aircraft seat. It can, however, be notably shorter, and have, for example, a length not exceeding half the height of the seatback 3, so that it makes possible the fastening of the seatback 3 at at least a desired maximum height for the seat bucket 1.

(22) It can also be longer, for example in the case of fastening said guide beam 5 in an upper part, for example at the level of a structure of the aircraft in an area of the ceiling of the cabin or of a bulkhead placed behind the seat.

(23) The guide beam 5, formed here from a structural tube with a hollow rectangular cross-section, this shape of the cross-section, however, not being necessary and illustrated by way of example, is held mounted in a sleeve 6, which advantageously incorporates a vertical damper, not shown in FIG. 6, intended for the dynamic absorption of forces along the main axis Z1 of the guide beam 5.

(24) In the case where such a damping device is incorporated into the sleeve 6, the guide beam, held approximately stationary by the damping device in ordinary conditions, slides in the sleeve 6 under the effect of forces introduced by accelerations whose downward vertical components that exceed a certain threshold can be likened to a crash situation.

(25) As clearly comes out from the structure described of the seat of the invention, the width of the guide beam 5 is independent from the width of the seat.

(26) The sleeve 6 is secured at two attachment points on each of two tracks 110a, 110b of the floor 100 of the aircraft by means of two posterior fastening feet 8a, 8b, and by two anterior fastening feet 9a, 9b, each equipped on their free end with an attachment interface corresponding to the geometry of the tracks 110a, 110b. The space between the ends of the fastening feet is adapted to the space of the attachment points on the tracks, conventionally 15 inches or 17 inches.

(27) The sleeve 6 and the fastening feet 8a, 8b, 9a, 9b form a connecting structure of the guide beam 5 to the floor 100 of the aircraft.

(28) In this example, the fastening feet 8a, 8b, 9a, 9b are made in the shape of structural arms formed at the level of the sleeve 6 and at the level of the attachment interfaces to make possible their fastening on the sleeve 6 and on the attachment interfaces on the tracks 110a, 110b. The guide beam 5 is preferably placed approximately at an equal distance from the tracks 110a, 110b.

(29) The guide beam 5, the sleeve 6 and the fastening feet 8a, 8b, 9a, 9b are, for example, made of metal according to conventional processes of machining, forming and assembly, or of composite material, and sized to take up the extreme forces applied to the aircraft seats.

(30) In one embodiment, the fastening feet 8a, 8b, 9a, 9b are designed so as to absorb a portion of the energy by plastic deformation to limit the accelerations sustained by an occupant of the seat during crash situations.

(31) In one variant embodiment, not illustrated, the sleeve 6 or a mounting structure is incorporated into a structure of the floor 100, and the guide beam 5 is held mounted in said sleeve or said mounting structure. In this variant, a lower part of the guide beam 5 is placed to be fastened to the mounting structure, and in particular when the mounting structure of the floor is located under an upper surface of said floor, its length is adapted to be extended under said upper surface of the floor.

(32) Such a variant makes it possible to avoid the use of floor tracks and simplifies the fastening of the seats, in particular when a longitudinal adjustment of the position of the seat is not necessary.

(33) The design of an aircraft seat with a single-beam console, whose principle according to the invention has just been described, exhibits, in relation to the existing devices, several advantages.

(34) It makes it possible in certain embodiments to install only a single device for each functionality (height/angle adjustment, compensation for movement, absorption of energy, . . . ) rather than at least two devices in the seats that have two lateral beams. Thus, the number of devices for the same number of functions is reduced. This is a major advantage in the context of the search for weight savings on any aeronautical equipment.

(35) Moreover, the limitation of the number of parts used for performing the same functions simplifies the system, and therefore reduces the risks of breakdowns; the reliability of the whole is increased.

(36) The central arrangement of the guide beam 5 makes it possible to clear the space occupied by the knees of a passenger located behind the seat, which makes it possible either to improve the comfort offered for a given space between two successive rows of seats or to reduce the interval between two successive rows of seats for equivalent comfort. Actually, in the case of console seats having two lateral beams, the spacing of the tracks for fastening to the ground in the alignment of which these structural beams find themselves corresponds in practice to the clearance of the knees. These beams therefore interfere with the knees of a passenger located right behind. The invention therefore improves the ergonomics of the position located behind the seat.

(37) Furthermore, in the case where the beam is mounted in the floor of the aircraft, the passenger located in a seat behind the seat under consideration has the possibility of placing his feet on the floor on each side of the beam and without being bothered by structures for fastening the seat to the floor, particularly to floor tracks, his comfort thus being improved.

(38) Also, the width of the bucket and the space between the two tracks are no longer directly linked in the invention, in contrast with the pre-existing devices, which provides an additional freedom in the choice of the width of the seat bucket without jeopardizing the support structure, the same support structure model being able to be used for different models of seat buckets.

(39) The invention also makes possible a guide beam cross-section that is larger than for two lateral beams (for withstanding the same forces), thus furnishing an increased inertia and increased rigidity. This single beam is found closest to the vertebral column of the passenger and in its axis provides an increased protection of the person in comparison with the existing devices in certain crash situations and situations of significant deformation of the airframe of the aircraft.

(40) The scope of this invention is not limited to the details of the embodiments considered above by way of example, but extends also to changes in the scope of a person skilled in the art.

(41) FIGS. 7a to 7f illustrate a variant and details of embodiment of the invention. In this variant, in which the device for adjustment of the inclination of the seat bucket, optional, is not shown, the guide beam 5 with a mainly rectangular cross-section, a cross-section shown diagrammatically by way of embodiment example in FIG. 7e, comprises at least one slide 51a, 51b on each side, advantageously participating in the reinforcement of the guide beam, and extending along its main axis Z1. In the lower part, this guide beam 5 comprises a structure for connecting to the floor 100 of the aircraft that comprises, on the one hand, a one-piece posterior foot 8b to which said guide beam is rigidly attached (foot on the left side of the seat in the example illustratedFIGS. 7a and 7b), and, on the other hand, an articulated posterior foot 8a, free in rotation around a transverse axis that is approximately parallel to the direction Y (foot on the right side of the seat in the illustrated exampleFIGS. 7a and 7b), so as to create an isostatic mounting adapted to take into account normal deformations of the structure of the floor of the aircraft.

(42) In this embodiment example, the one-piece posterior foot 8b and the articulated posterior foot 8a that are integral with the guide beam 5 each comprise an interface for attachment on a fastening position on tracks 110a, 110b. Moreover, each so-called stationary foot 8a, 8b comprises a part that can be extended in the direction X, forming the so-called adjustable anterior foot 9a, 9b that itself comprises in a forward part an interface for attachment on the tracks. This part that can be extended, for example by sliding an arm in the corresponding stationary foot or by mounting adjustable feet provided with arms of different lengths, makes it possible to adapt the seat to a separation of existing fastening points of an aircraft floor in the direction of the longitudinal axis.

(43) The seatback 3 of the seat bucket 1 comprises on its rear part structural stiffeners 12a, 12b placed symmetrically on both sides of the center line of the seatback 3, and spaced so as to make possible the passage of the guide beam 5. The structural stiffeners 12a, 12b slide, for example by means of pads or rollers integral with said stiffeners, in anterior slides 51a of the guide beam 5. They are furthermore integral with lower parts of two dampers 7a, 7b, located on both sides of the guide beam 5, at the level of posterior slides 51b. The dampers 7a, 7b are integral by an upper part with the top part of the guide beam 5.

(44) By such an arrangement, the dampers 7a, 7b absorb energy linked to approximately vertical forces generated by vertical accelerations, in particular in crash situations.

(45) The characteristics of the dampers 7a, 7b depend here again on the extreme conditions of accelerations and of weight that the seats must support.

(46) In one embodiment, not shown in the figures, the dampers 7a, 7b, or a single damper, are arranged on the inside of the guide beam, which makes it possible to obtain a more compact unit.

(47) The seat of FIGS. 7a and 7b comprises a safety belt, present on all aircraft seats in accordance with regulations, formed by two half-belts 13a, 13b placed on each side of the seat and intended to be connected by an attaching buckle. Each half-belt 13a, 13b, which must withstand the forces during a crash situation, is attached by one end to a structural stiffener 12a, 12b that is integral with the seat bucket 1. It then goes through a first belt guide 14a, 14b that is integral with the guide beam 5, therefore stationary during vertical movements of the seat bucket in relation to the guide beam, then through a second guide 15a, 15b that is integral with the posterior foot 8a, 8b located on its side of the seat, therefore also stationary during vertical movements of the seat bucket in relation to the guide beam, before going up above the seat pan 2, advantageously through passage openings in the lateral edge of the seat pan 2, to be fastened to the other belt part, when the latter is attached.

(48) In this way, when the seat bucket 1 of the seat moves along the main axis Z1 of the guide beam 5, the belt length between the edges of the seat pan that holds the occupant of the seat remains generally unchanged. By this double passage through guides attached to the stationary structure, a device for compensation of the length of the safety belt is obtained here.

(49) This device makes it possible, on the one hand, for the occupant of the seat to adjust a vertical position of the seat bucket when his belt is attached, without it being necessary to make use of inertia reel belts, and, on the other hand, to compensate for the length of the belt when the seat is moved downward to absorb the energy of a crash situation, the occupant of the seat being held in the seat without being excessively squeezed or loosened by the belt, a result that an inertia reel belt does not make it possible to achieve in the case of strong accelerations that are typical in a crash situation.

(50) This device further makes it possible, by shifting the points for taking up the forces of the belt to the high-strength elements of the stationary structure of the seat, to reduce the forces at the level of the fastening of the belt to the bucket and therefore to avoid having reinforcements for the seat bucket 1 that are necessary in the solutions that consist in fastening the belt directly at the level of the seat pan 2.

(51) In a more specific variant of the use that is presented in detail above, illustrated in FIG. 8, the two feet 8a, 9a connected to the guide beam 5 are articulated around a transverse axis Y, and a brake or pawl mechanism, not shown, of standard type stops the inclination of the guide beam in relation to the foot under consideration and therefore the seat in a selected inclination in relation to the vertical. The other feet 8b, 9b are, as in the case described previously, left free in rotation, so as to be in a position to support the deformations of the floor, normal or exceptional, without introducing stresses into the structure of the seat as a result of a twisting of the floor.

(52) In one embodiment, illustrated in the embodiment example of FIG. 8, the seatback 3 comprises, on each side of the guide beam 5, a fastener articulated at the level of the lower attachment 10 that slides freely in an anterior slide 51a of said guide beam. Furthermore, the seatback 3 comprisesoffset in height in relation to the lower attachment, on each side of the guide beam 5 at the level of the upper attachment 11a device for adjusting the distance of said upper attachment to said guide beam formed in the example illustrated by a fastening means having two independent arms 112a, 112b, subject by one of their ends to the same transverse axis of rotation at the level of the seatback 3, and by their other ends to a lock pin that slides in the anterior slide 51a. This device with two arms makes it possible to adjust the inclination of the seat bucket 1 by variation of the angle between the arms, an opening of the angle bringing the upper attachment 11 of the seatback of the guide beam 5 closer and conversely a closing of the angle moving said upper attachment away.

(53) In a variant embodiment, the principles for making the upper and lower fasteners are reversed.

(54) A damping device ensures the holding in a selected position of the seat bucket 1 along the guide beam 5 while ensuring a mechanical link between said guide beam and a take-up point of said seat bucket, advantageously at the level of one of the upper or lower attachments. In the case of dynamic stress downward on the seat, the seat bucket 1 will have a tendency to slide downward while remaining guided along the anterior slide 51a, the energy being then absorbed by one or more dampers, not shown in FIG. 8, placed on one or both sides of the guide beam 5, for example at the level of posterior slides 51b, or else placed inside the guide beam 5, and connected to the attachment points of the seatback 3 by at least one recoil wire.

(55) The invention therefore makes it possible to produce a seat of a design that is both simpler than according to the known designs and that can incorporate devices for absorption of energy while having improved ergonomic characteristics.

(56) A seat according to the invention is thus particularly suited to equip helicopters whose standards in the area of protection of the occupants in situations of vertical crashes are particularly stringent.

(57) An aircraft provided with such seats makes it possible to benefit from a reduced weight of the accommodations and from a better use of the space of the cabin and of the pilot compartment.