GENERAL TECHNICAL FIELD AND PRIOR ART

The present invention relates to a modular seat configured to take various positions. The present invention also relates to a method for changing the position of the modular seat.

In transportations such as trains and aircraft where users may spend few to several hours, the comfort provided by the seat is important. One way to make a seat more comfortable is for it to have an adjustable inclination of the seatback.

The inclination of the seatback is the angle between a vertical axis (when considering the floor supporting the seat to be horizontal) and the plan of extension of the seatback.

There are two main types of movements to modify the inclination of the backrest of a seat.

A first type of movement consists in a rotation of the seatback, which push back the upper part of the seatback from a distance of, for example, 10 to 20 cm. Such a movement allows to increase the angle opening between the seat surface and the seatback and give more comfort to the user. However, according to this type of movement, the seatback of one seat may protrude in the space of a passenger sitting in a seat placed behind.

A second type of movement consists in placing the seat in a shell which does not move, the seat moving inside the shell. According to this strategy, the angle between the seat surface and the seatback is opened by translating forward the seat surface while the inclination of the seatback increases. The advantage of this type of seat is that the movement of the seat does not reduce the space left behind said seat. However, the translation of the seat surface forward limits the space left for the legs of the user.

A solution to avoid the above-mentioned drawbacks could be to leave more space between two consecutive seats. However, in transportations, it is necessary to put a maximum number of seats in a limited space, mainly for economic reasons.

The solution in transportations is therefore usually to suppress the possibility to modify the inclination of the seatback of a seat. According to this solution, the inclination of the seatback constitutes a compromise between a comfortable inclination and satisfying space, on one side, for the legs of the user and, on another side, for the passenger placed behind the seat. However, in the case for example of aircraft seats, for security reasons the inclination of the seatback is low during the phase of take-off and landing and it is not suitable to leave the passengers in such a position during the entire flight.

GENERAL PRESENTATION OF THE INVENTION

An aim of the invention is therefore to propose a seat which could be placed in various positions, in particular positions with various inclinations of the seatback, without encroaching the space left behind the seatback and while leaving enough space for the legs of the user sitting on the seat.

Another aim of the invention is to propose a seat offering to the user an ergonomic position regardless of the position of the seat.

According to a first aspect, the invention is directed towards a modular seat comprising a fixed structure configured to be linked to a floor and a mobile structure movably linked to the fixed structure, the mobile structure comprising a seat surface extending according to a first plane and a seatback extending according to a second plane, the first plane and the second plane intersecting along a first axis so as to form a fixed angle between the first and second planes, said fixed angle having a value ranging from 90° to 130°, the mobile structure being able to adopt various predetermined or self- determined positions relative to the fixed structure while maintaining unchanged the value of the fixed angle, the passage from a position to another being carried out by rotation of the mobile structure around a virtual axis which is parallel to the first axis.

The modular seat of the invention is configured to take different positions while living enough space behind the seat and also enough space for the legs of the user. Further, the fixed angle between the seat surface and the seatback allows the user to be in a comfortable posture regardless the position of the seat. It is therefore possible to place the seat of the invention in an area where the space is limited, for example in the economic class of an aircraft.

In a preferred embodiment, the fixed angle may have a value ranging from 95° to 120°, and more preferably from 100° to 115°.

Preferably, the first axis goes through the cushion reference point (CRP) which is defined as the intersection of the plane of the seat cushion, which may be the first plane, with the plane which touches the forward- most surface of the uncompressed center of the seat back, which may be the second plane.

In the invention, a self-determined position is any position chosen by the user and which was not previously defined. A pre-determined position is a position defined at the conception of the seat and then chosen by the user.

Some preferred but not limiting features of the method described above are the following, taken individually or in combination:

- one of the fixed structure and the mobile structure comprises an elongated translation area and the other of the fixed structure and the mobile structure comprises a positioning element which moves relative to the translation area so as to modify the position of the mobile structure relative to the fixed structure;

- the elongated translation area is a rib comprising stopping points and the positioning element is a male part configured to cooperate with the stopping points, each cooperation between the positioning element and one of the stopping points corresponding to one of the predetermined positions of the seat; the stopping points may be notches positioned along the rib;

- the elongated translation area is a rib and the positioning element is a male part sliding along the rib, the positioning element being associated with a blocking element which allows to stop the sliding of the positioning element once a self-determined position is reached; the blocking element may be an actuator;

- the seat comprises an actuator connecting the mobile structure to the fixed structure so as to maintain the seat in one of the predetermined or self-determined position; the actuator is configured to adopt, on one side, a first position in which the mobile structure is in a stationary position relative to the fixed structure, and, on another side, a second position in which the mobile structure is free to move relative to the fixed structure;

- the seat comprises a controlling element able to act on the actuator in order to place said actuator in the first position or in the second position; in the first position, the actuator blocks the sliding of the positioning element along the translation area and on the second position, the actuator allows the sliding of the positioning element along the translation area; the controlling element may be a button accessible by a user sitting on the seat and actionable manually by said user;

- the fixed structure forms a housing for the mobile structure in which the mobile structure is able to slide;

- the seat surface comprises a first part which is fixed relative to the seatback and a second part which is mobile relative to the first part, the mobility of the second part relative to the first part being a rotation around a second axis which is parallel to the first axis;

- the seat comprises one or two armrests which are connected to the mobile structure and which follow the movement of the mobile structure while said mobile structure moves relative to the fixed structure; - the predetermined or self-determined positions comprise an equilibrium position in which the mobile structure places itself spontaneously when the positioning element is free to slide along the translation area; and

- the seat comprises a head rest which is assembled with the fixed structure and which is able to translate relative to the fixed structure to adapt its position to the position of the mobile structure.

According to a second aspect, the invention is directed towards a set of seats comprising at least one seat according to the first aspect, wherein the position of the mobile structure of each seat may be changed relative to the corresponding fixed structure, independently of the position of the mobile structure of the other seats.

According to a third aspect, the invention is directed towards a method for changing the position of the mobile structure relative to the fixed structure in a seat according to the first aspect, the method comprising:

1) when starting from one of the predetermined positions which is not the equilibrium position:

- place the actuator in the second position,

- let the mobile structure move spontaneously to the equilibrium position,

- place the actuator in the first position to block the sliding of the positioning element in the translation area at a stopping point or at a self-determined position corresponding to the equilibrium position of the seat, or

2) when starting from the equilibrium position:

- place the actuator in the second position,

- exert a pressure of the mobile structure until said mobile structure adopt one of the predetermined or self-determined position which is not the equilibrium position, and

- place the actuator in the first position to block the sliding of the positioning element along the translation area at a stopping point or at a self- determined position corresponding to the selected position. According to a fourth aspect, the invention is directed towards an aircraft comprising at least one seat according to the first aspect or at least one set of seats according to the second aspect.

PRESENTATION OF THE FIGURES

Other features and advantages of the invention will emerge from the following description, which is purely illustrative and non-limiting and must be considered with respect to the appended figures in which:

- Figure 1 is a schematic perspective view of a part of a set of seats according to a first embodiment;

- Figure 2 is a schematic perspective view of the set of seats according to figure 1 with additional parts;

- Figure 3 is a schematic perspective views of the set of seats according to figure 1 with additional parts;

- Figures 4a to 4d are schematic perspective views of the set of seats according to the first embodiment in different positions;

- Figures 5a to 5c are schematic perspective views of a part of the set of seats of figures 4a to 4d;

- Figures 6a to 6d are schematic side view of the set of seats of figures 4a to 4d; and

- Figure 7 is a schematic side view of a set of seats according to a variation of the first embodiment.

DESCRIPTION OF SEVERAL EMBODIMENTS

In the following description, the terms such as "inferior", "superior", "above", "behind", and the like, refer to a seat in its positioned of use, i.e. positioned on the floor.

In the embodiment described below, a set 1 of modular seats (or seats) comprises two seats 2 placed next to each other. In the following description, only one of the two seats will be described but the description also applies to the second seat which is identical. In another possible embodiment, the two seats may be different. In reference to figures 1 to 3, the seat 2 comprises a fixed structure 10 configured to be linked to a floor 3, for example the floor of an aircraft, and a mobile structure 30 movably linked to the fixed structure 10.

The mobile structure 30 comprises a seat surface 32 extending according to a first plane Pl and a seatback 34 extending according to a second plane P2, the first plane Pl and the second plane P2 intersecting on a first axis XI so as to form a fixed angle between the first and second planes, said fixed angle having a value ranging from 90° to 130°, preferably from 95° to 120°, and more preferably from 100° to 115°.

The mobile structure 30 is configured to adopt various predetermined positions or self-determined positions relative to the fixed structure while maintaining unchanged the value of the fixed angle. The passage from a position to another is carried out by rotation of the mobile structure 30 around a virtual axis Xv which is parallel to the first axis XI.

The modular seat of the invention is configured to take different positions while living enough space behind the seat and also enough space for the legs of the user. Further, the fixed angle between the seat surface and the seatback allows the user to be in a comfortable posture regardless the position of the seat.

Advantageously, the seat of the invention can be placed in an area where the space is limited, for example the economic class of an aircraft.

In reference to figure 1, the fixed structure 30 comprises a lower part 12, an upper part 15 and a middle part 14 which is positioned between the lower part 12 and the upper part 15. The lower part 12 and the middle part 14 are fixed to an external lateral element 16 and to an internal lateral element 18. The external and internal lateral elements 16 and 18 have a crescent shape, the external lateral element 16 being longer than the internal lateral element 18.

In a possible embodiment wherein the seat is single, the seat comprises two external lateral elements of the same length.

The lower part 12 also comprises a rear wall 20 extending in a lateral direction and attached to the external lateral element 16 and to the internal lateral element 18. The lower part 12 further comprises two inner lateral walls 22 extending perpendicularly to the rear wall 20 an attached thereto. The rear wall 20 and the inner walls 22 constitute reinforcing parts which allow to support the mobile structure 30.

The lower part 12 also comprises an elongated part 24 extending in a lateral direction and which is fixed to the external lateral element 16 and to the internal lateral element 18. The elongated part 24 also support the mobile structure 30.

An actuator 60 which is, in this embodiment, a hydraulic actuator, is fixed by a first end (which is not visible on the figures) to the fixed structure 10 and by a second end 62, opposite to the first end, to the mobile structure 30.

A support structure 26 allows to support the fixed structure 10 and to connect said fixed structure 10 to the floor 3. The support structure 26 is preferably attached to the floor 3. According to one embodiment, the support structure 26 may be a classical support structure usually present in an aircraft and to which the fixed structure 10 is adapted.

The upper part 15 comprises four fastening elements 17 allowing to fix a cover 19 illustrated on figure 3 and which allows to hide some parts of the fixed structure 10. The upper part 15 further comprises four fixation devices 21 allowing to slidably connect two headrests 28 to the fixed structure. In particular, each fixation device 21 comprises two rails 23 along which the headrests 28 may translate in a longitudinal direction, i.e. a direction perpendicular to the first axis XI.

The headrests 28 which are illustrated on figures 4a to 4d are therefore assembled to the fixed structure 10 and are able to translate relative to said structure in order to adapt their position to the position of the mobile structure 30 relative to the fixed structure 10. The head of the user may therefore always be sustained regardless the position of the mobile structure 30 relative to the fixed structure 10.

The fixed structure 10 also comprises two positioning elements 29, one being fixed to the external lateral element 16 and the other being fixed to the internal lateral elements 18. As described later, the positioning element cooperate with the mobile structure 30 to guide the changing of position thereof.

In reference to figures 2, 3 and 4a-d, the mobile structure 30 comprises a seat surface 32 placed mainly above the lower part 12 of the fixed structure 10 and a seatback 34 mainly placed against the middle art 14 of the fixed structure 10. The seat surface 32 and the seatback 34 are positioned substantially between the external and internal lateral elements 16 and 18. The fixed structure 10 therefore forms a housing for the mobile structure 30.

The seat surface 32 is fixed to the second end 62 of the actuator 60.

The seat surface 32 is bordered on each on its two lateral sides by an external guiding piece 36 which extends until an upper end 38a of the seatback 34 and by an internal guiding piece 37 which extends until a lower end 38b of the seatback 34. The external and internal guiding pieces 36 and 37 are placed between the external and internal lateral elements 16 and 18 and extend substantially parallel to said lateral elements.

The external and internal guiding pieces 36 and 37 are provided, on their external face, i.e. on the side facing the external and internal lateral elements 16 and 18 respectively, with an elongated translation area 40.

As illustrated in more details on figures 5a to 5c, the positioning element 29 cooperate with the elongated translation area 40. In this embodiment, the elongated translation area 40 is a rib having a curved shape and the positioning element 29 is a male part which is inserted inside the elongated translation area 40 and which is configured to translate along said translation area 40 in order to guide the changing of the position of the mobile structure 30.

In another possible embodiment, the elongated translation area may belong to the fixed structure 10, for example to the external and internal lateral elements 16 and 18, and the positioning element 29 may belong to the mobile structure, for example to the external and internal guiding pieces 36 and 37.

The seat 2 further comprises two armrests 42, one external armrest 42a and one internal armrest 42b, which are each connected to the mobile structure 30 by two fixation members 43. The armrests 42 follow the movement of the mobile structure 30 which means that their position relative to the mobile structure 30 does not change relative to said structure while the mobile structure 30 move relative to the fixed structure 10.

According to a possible embodiment, the seat is single and the seat comprises two external armrests.

The internal armrests 42b comprise an upper part 44b which may be lifted by the user to form a single bench.

The external armrests 42a comprises an upper part 44a which is placed above a supporting structure 46 comprising the fixation members 43. The supporting structure 46 is placed so that the external lateral element 16 is positioned between the supporting structure 46 and the external guiding piece 36.

The external armrests 42a comprises a controlling element 47 which is a button the user can press to act on the actuator 60. The actuator 60 is configured to adopt, on one side, a first position in which the mobile structure 30 is in a stationary position relative to the fixed structure 10, and, on another side, a second position in which the mobile structure 30 is free to move relative to the fixed structure 10. The second position is adopted when the user acts on the controlling element 47 and, when the user releases the controlling element 47, the actuator goes back to the second position.

When the mobile structure 30 is in a stationary position relative to the fixed structure 10, the actuator 60 is in the first position. By pushing the button 47, the user places the actuator 60 in the second position allowing the mobile structure 30 to move relative to the fixed structure 10. The positioning element 29 is then allowed to slide in the translation area 40 and guide the movement of the mobile structure 30 relative to the fixed structure 10.

As illustrated on figures 6a to 6d, the seat 2 comprises cushions which cover the mobile structure 30. In particular, a first cushion 50 covers the seat surface 32, a second cushion cover the seatback 34, and a third cushions cover the headrest 28. The armrests 42a and 42b are also covered by textiles parts.

In reference to figures 4a to 4d, the different positions which may be taken by the mobile structure 30 relative to the fixed structure 10 will now be described.

Figure 4a illustrates a secure position (TTL position) of the mobile structure 30 during the Taxi Take Off Landing (TTL) phase of the flight. In this position, the inclination of the seatback is low and the comfort limited.

Figure 4b illustrates a first active position (Al position) which allows the user to use a table positioned on the back of the front seat, for example to work or take a meal.

Figure 4c illustrates a second active position (A2 position) which aims at allowing the user to exert a pressure on his legs while sitting in the seat 2. This position allows the user to use the muscle of his legs during a long flight.

Figure 4d illustrates an equilibrium position (Eq position) which corresponds to a position spontaneously adopted by the mobile structure 30 when said mobile structure is able to slide relative to the fixed structure 10. In this equilibrium position, all the part of the body are properly sustained and no part of the body suffer of any excessive pressure or tension.

For the four predetermined positions, i.e. TTL position, Al position, A2 position and Eq position, the angle between the first plane Pl and the second plane P2 is the same and ranges from 90° to 130°, preferably from 95° to 120°, and more preferably from 100° to 115°. This angle corresponds to an optimized position of the body wherein the angle between the shin and the femur and the angle between the femur and the torso allow the user to feel comfortable during a long flight.

For all the four predetermined positions, the headrest 28 may take different positions depending of the size of the user. The position of the headrest 28 may be chosen independently from the position of the mobile structure 30. According to a possible embodiment, the seat may comprise more or less than four predetermined positions. For example, the seat 2 may take all position allowed by the length of the translation area 40.

According to another possible embodiment, the angle between the first plane Pl and the second plane P2 may be changed by the user but not during the moving of the mobile structure 30 from a position to another.

In reference to figures 5a to 5c, the mechanism for moving the mobile structure form a predetermined position to another is now described.

In this embodiment, the elongated translation area 40, which is a rib, belongs to the mobile structure 30 and in particular to the external and internal guiding pieces 36 and 37. The elongated translation area 40 comprises two ends, a front end 41a and a rear end 41b.

The positioning element 29 which belongs to the fixed structure comprise a circular head 29' which is inserted inside the elongated translation area 40 and which is able to translate from the front end 41a to the rear end 41b and from the rear end 41b to the front end 41a. Two adjusting rollers 49 placed next to each positioning element 29 allow to maintain the mobile structure 30 in a straight axis which is perpendicular to the first axis XI while moving relative to the fixed structure 10.

When the actuator 60 is in the second position, the positioning element 29 translates inside the elongated translation area 40 and the mobile structure 30 slide relative to the fixed structure 10. The equilibrium position is the position in which the mobile structure 30 places itself spontaneously when the positioning element 29 is free to slide along the translation area 40.

Once the mobile structure 30 is in the desired position, the sliding of the positioning element 29 is blocked by the release of the controlling element 47 which places the actuator 60 in the first position. The actuator 60 therefore maintains the seat in the chosen position (which is one of the predetermined or self-determined positions) and the positioning element 29 stays in a fixed position in the elongated translation area 40.

In particular, the elongated element 40 comprises stopping points and the positioning element 29 is configured to cooperate with the stopping points, each cooperation between the positioning element 29 and one of the stopping points corresponding to one of the predetermined positions of the seat 2. The stopping points are notches in this embodiment.

While moving relative to the fixed structure 10, the mobile structure 30 is always in contact with the fixed structure 10.

The actuator is operable by a user sitting on the seat. The position of the seat is then easily chosen by the user and without using any engine.

When starting from one of the predetermined positions which is not the equilibrium position, the method for changing the position of the mobile structure 30 relative to the fixed structure 10 in the seat 2 comprises the following step:

- the user placed in the seat 2 places the actuator 60 in the second position,

- the user let the mobile structure 30 move spontaneously to the equilibrium position, and

- the user places the actuator 60 in the first position to block the sliding of the positioning element 29 in the translation area 40 at a stopping point or at a position corresponding to the equilibrium position of the seat 2.

The mobile structure 30 is therefore maintained in the equilibrium position.

When starting from the equilibrium position, the method for changing the position of the mobile structure 30 relative to the fixed structure 10 in the seat 2 comprises the following step:

- the user placed in the seat places the actuator 60 in the second position,

- the user exerts a pressure on the mobile structure 30 until said mobile structure adopts one of the predetermined or self-determined positions which is not the equilibrium position, and

- the user places the actuator 60 in the first position to block the sliding of the positioning element 29 along the translation area 40 at a stopping point or at a position corresponding to the selected position.

The mobile structure 30 is therefore maintained in the chosen position. In reference to figures 6a to 6d, the angles between the first plane Pl and the second plane P2 as well as the angle between each of the first plane Pl and the second plane P2 with the floor are described.

As known by the person skilled in the art, the cushion reference point (CRP) is defined as the intersection of the plane of the seat cushion with the plane which touches the forward-most surface of the uncompressed center of the seat back.

In the embodiment illustrated on figures 6a to 6b, the plane of the seat cushion in Pl and the plane which touches the forward-most surface of the uncompressed center of the seatback is plane P2. The first plane Pl and the second plane P2 intersects according on the first axis XI which comprises the CRP.

In this embodiment, the fixed angle between the first plane Pl and the second plane P2 has a value of 105°.

A virtual axis Xv is the axis which is parallel to the first axis XI and which comprises the center of a circle comprising the CRP for each of the four possible positions of the mobile structure 30.

On figure 6a, the mobile structure 30 is in the TTL position. In this position, the angle between the first plane Pl and the floor has a value of 10°, the angle between the plane P2 and the floor has a value of 65°, and the angle between a line L and the horizontal axis has a value of 53°. The line L is a line which is perpendicular to the first axis XI and which links the CRP and the virtual axis Xv.

On figure 6b, the mobile structure 30 is in the first active position. In this position, the angle between the first plane Pl and the floor 3 has a value of 2°, the angle between the plane P2 and the floor 3 has a value of 73°, and the angle between a line L and the horizontal axis has a value of 45°.

On figure 6c, the mobile structure 30 is in the second active position. In this position, the angle between the first plane Pl and the floor 3 has a value of -4°, the angle between the plane P2 and the floor 3 has a value of 79°, and the angle between a line L and the horizontal axis has a value of 39°. On figure 6d, the mobile structure 30 is in the equilibrium position. In this position, the angle between the first plane Pl and the floor 3 has a value of 17°, the angle between the plane P2 and the floor 3 has a value of 58°, and the angle between a line L and the horizontal axis has a value of 60°.

According to a variation of the first embodiment illustrated on figure 7, the seat surface 32 comprises a first part 54 which is fixed relative to the seatback 34 and a second part 52 which is mobile relative to the first part 54, the mobility of the second part 52 relative to the first part 54 being a rotation around a second axis X2 which is parallel to the first axis.

The second part 52 may therefore be inclined relative to the first part 54 which allow the legs of the user to be in a lower position and avoid the seat surface to exert excessive pression on the legs of the user.

Other embodiments can be envisaged and a person skilled in the art can easily modify the embodiments or examples of realization exposed above or envisage others while remaining within the scope of the invention.