WO1997042050A1

WO1997042050A1 - Seat portion actuating system

Info

Publication number: WO1997042050A1
Application number: PCT/FR1997/000813
Authority: WO
Inventors: Patrick Quesne
Original assignee: Kollmorgen Artus
Priority date: 1996-05-06
Filing date: 1997-05-06
Publication date: 1997-11-13
Also published as: FR2748240B1; FR2748240A1; AU2902797A

Abstract

A seat portion actuating system enabling each portion of a seat to be moved by means of a respective actuator (22, 23, 24, 25, 26) controlled by a central processing means (50) depending on a position selected via at least one data input means (20A, 20B, 21A, 21B, 29). The system comprises means (60, 29, 30) for connecting the central processing means (50) of one seat so at least one central processing means (50) of another seat to enable synchronised operation of the actuators of said seats via any one of the input means thereof. The input means consist of a smart card reader, an internal seat keypad or an external one advantageously provided with a built-in reader.

Description

Seat element actuation system

Technical area

The present invention relates to an actuation system intended for the motorization of seats, for example the passenger seats of aircraft.

Prior art

Until now, in the air transport sector, there have essentially been two types of seat element actuation system, one provided with an asynchronous motorization from the onboard 400 Hz network and the other with '' a continuous 115V motorization. The first of these motorizations, thanks to the high rotation speed which it allows, makes it possible to obtain actuators of reduced size. However, this reduction in size is at the expense of a significant noise level taking into account the noise generated by this engine and in particular by its reducing stages. As a result, this type of engine is currently only used at the level of the seats in the cockpit. On the contrary, the second engine, by the low noise it generates, is more particularly suitable for passenger seats. Unfortunately, this engine is much more bulky than the previous one. Also, the manufacturers who have all the same retained this latter solution had to accept the increase in weight that it implies by limiting the possibility of simultaneous control of the actuators offered to the passenger while keeping the original kinematics of the seats. This results in a very low possibility of adaptation of these seats except at the cost of heavy technical modifications which seriously affect the profitability of the product. In particular, it is impossible with current seats to control more than two seat elements simultaneously. It follows that in the classic case of first class double passenger seats, a user will not be able to simultaneously control a straightening of his backrest and an adjustment of his headrest, for example if his neighbor next to the seat at the same time controls the movement of his leg rest for example. In addition, the electromechanical performance of these actuators remains very average, as well as the safety which can be compromised (presence of high voltages) in the event of an insulation fault. In addition, whatever the type of engine used, these systems present significant difficulties in terms of maintenance and testing. Indeed, currently the initial configuration of each seat must be carried out individually, and in particular the limit stops must be set one after the other for each actuator. This results in a particularly long development time.

Definition and object of the invention

The object of the present invention is to overcome the aforementioned drawbacks by proposing a system for actuating seat elements which may be suitable in particular for pilots and passengers of an aircraft and which, by virtue of its structure, offers safety and comfort of improved use and operation. In particular, an object of the invention is to allow simultaneous control of the various seat elements. Another object is to avoid any mechanical adjustment on the seat, in particular during the step of mounting the actuation system in the seat and to simplify it later in terms of maintenance. Yet another object of the invention is to offer the user new complementary functions.

These aims are achieved by a seat element actuation system, each seat element being able to be moved by means of an individual actuator controlled from a centralized processing means as a function of displacement positions defined by at least data entry means, a system characterized in that it comprises means making it possible to connect the centralized processing means of a seat to at least one centralized processing means of another seat to allow joint movement of the actuators of these seats from any of the means of entry of these seats.

The centralization of all of the seat element control data at the level of the single processing means makes it possible both to ensure great flexibility of use and to facilitate the various operating operations. It allows, in addition to increased security, to facilitate the configuration of seats and their maintenance which can therefore be carried out globally and no longer individually.

The connection means between seats comprise an interface module ensuring a connection between an external bus connecting each double seat and an internal connection bus by means of centralized processing. These internal and external buses include a serial link which can be a wired link of IIC or RS232 type for example or a fiber optic link, or even a wireless infrared or ultrasonic link for example. Preferably, the external bus can be connected to an external control unit of the PC microcomputer type or the like or to a console in the cockpit.

The actuation system according to the invention may further comprise a converter means disposed between the internal bus and data output means for ensuring a conversion of a first communication protocol relating to the information circulating on the internal bus into a second communication protocol compatible with these data output means. According to the invention, each individual actuator comprises a DC motor. Thus, noise pollution from the asynchronous motor is avoided. Preferably, the centralized processing means also comprises means for determining the variation in intensity of the current per unit of time (dl / dt) passing through the DC motor of each actuator and for controlling a short movement of this actuator in opposite direction, if this variation exceeds a predetermined threshold.

Likewise, advantageously, the centralized processing means comprises means for controlling the switching off of a determined actuator in the event of failure of this actuator, the other actuators remaining in service. It may further comprise means for temporarily switching off all of the actuators of a seat if, in the event of simultaneous control of all the actuators of a given double seat, the power consumed exceeds a predetermined threshold.

According to the invention, the data entry means can be constituted by an external maintenance keyboard advantageously provided with an integrated reader of memory cards or simply by a reader of memory cards or smart cards.

In a preferred embodiment, the actuation system according to the invention further comprises a first preprogrammed card (“configuration card”) in which the hardware configuration of the double seat is stored, for example the number of individual actuators or l 'maximum current intensity admissible by each of them, and which is intended to be read by said data input means to initialize said centralized processing means. Advantageously, it also comprises a second preprogrammed card (“stop adjustment card”) in which the extreme positions of movement of each actuator previously defined in a keyboard are memorized, and which can be read by any of said means. data entry to constitute data that can be reused by the seat manufacturer for automatic adjustment of the electric actuator strokes or their internal test.

The use of a card reader makes it easier for maintenance personnel and the seat builder to install, adjust and test the actuation system in the structure intended to receive it in the double seat.

The actuators comprise a worm gear-toothed wheel assembly in direct drive forming a single reducing stage and some of these actuators can be fitted with potentiometric type sensor means delivering information proportional to the actuator stroke.

Advantageously, these sensor means cooperate with a rack integral with the worm-gear assembly, so that the actuator can be moved, in particular during its mounting in the seat, without affecting the adjustment of these sensor means.

The actuation system according to the invention is particularly suitable for the control of aircraft passenger seat elements and in particular the first class or business class double seats.

Brief description of the drawings

Other characteristics and advantages of the present invention will emerge more clearly from the following description, given by way of non-limiting illustration, with reference to the appended drawings, in which:

FIG. 1 shows in perspective a double passenger seat of an aircraft provided with the actuating system of seat elements according to the invention,

FIG. 2 is a schematic sectional view of the double seat of FIG. 1 in which the various actuators necessary for the motorization of this seat appear in functional form,

FIG. 3 represents a data input means for controlling the various actuators,

FIG. 4 illustrates the organization of the different command and control circuits for the seat element actuators,

- Figure 5 is a simplified diagram of the control circuit of an actuator with position feedback, - Figure 6 shows an example of a first type of linear actuator of a seat element, and

- Figure 7 shows an example of a second type of linear actuator of a seat element. Detailed description of a preferred embodiment

The seat element actuation system according to the invention is illustrated in FIGS. 1 and 2 at the level of a first class double passenger seat of an aircraft. Of course, this actuation system can be applied to a simple, first class or business class seat, as to any other type of motorized seat, in particular in rail transport (high-speed trains for example), road (coach) touring) or river (navigator pilot seat in particular). This double seat 10 has a right seat 10A and a left seat

10B identical and independent of each other allowing to receive two passengers side by side. Each seat 10A or 10B conventionally comprises a backrest 12, a headrest 13, a lumbar portion 14, a seat 15 and a leg rest 16. Each seat 10A, 10B can also advantageously be equipped for example with means of communication , such as a telephone handset 17, audio-video listening means, such as a stereophonic headset 18 and display means, for example a color television set 19. The motorization of each seat, that is to say the control of the different actuators , is provided from at least one data input means such as a keyboard 20 or a device for memorizing and reading personal data of the memory card or chip type 21.

The different actuators for the motorization of each seat are illustrated very schematically in Figure 2. It is thus possible to raise a first actuator 22 to allow the inclination of the leg rest 16, a second actuator 23 for movement up and down of the seat 15 of the seat, a third actuator 24 for the inclination of the backrest 12, a fourth actuator 25 for the displacement of the headrest 13 and a fifth actuator 26 for the adjustment of the lumbar portion 14. Each of these actuators is advantageously constituted by a direct current motor whose output shaft is in direct engagement (thus creating a single reduction ratio) with a connecting shaft moving linearly with each rotation of the motor and connected to the element seat to be controlled (see for example the actuators which will be described later with reference to Figures 6 and 7). The use of direct current motors instead of the usual asynchronous motors makes it possible to obtain particularly low noise levels and well suited to passenger seats.

FIG. 3 describes a keyboard type data input means allowing the user of each seat to control independently and optionally simultaneously the motorization of the various actuators of the aforementioned seat elements and of memorizing, if desired, the positions of each of the actuators which it has thus defined. This input means, for example the keyboard 20 of the right seat, is provided with different keys allowing individual control of each of the seat actuators. A first key 32 makes it possible to act on the actuator of the leg rest 16, a part 32A of this key controlling the linear movement of this actuator in a first direction of movement and a second part of this key 32B controlling the movement of this actuator in a second direction of movement, opposite to the previous one. Stopping this command causes the actuator to lock in the position reached at the time of stopping. A second key 33 allows the actuator of the seat 15 to be controlled. It also includes parts 33A and 33B for moving this seat in two opposite directions (up and down). It is the same for the key 34, with the parts 34A, 34B, allowing an inclination of the backrest 12, for the key 35, with the parts 35 A, 35B, acting on the displacement of the headrest 13 and for the key 36 with the parts 36A, 36B for adjusting the lumbar part 14. Keys 37, 38 and 39 are further provided for positioning the seat in positions memorized in advance, respectively in a straight sitting position, in an intermediate rest position and in an extended position. A key 40 for memorizing the position of the different actuators, defined by the preceding keys, is also provided as well as a key 41 for controlling the actuators from the recall of these positions thus memorized.

FIG. 4 shows in a simplified manner the organization of the command and control circuits of the different actuators of the double seat 10. These elements are organized around a centralized processing means common to each seat 10A, 10B and formed of a housing electronic control 50 to which are connected on the one hand the different actuators 22, 23, 24, 25 and 26 of each seat and on the other hand the data input means 20A, 20B and 21A, 21B. The box 50 firstly and conventionally comprises a transformation / rectification / filtering circuit 51 which develops a DC voltage from the on-board network 115V / 400Hz (an electronic circuit breaker can also be provided). Advantageously, this circuit 51 will be provided with means allowing direct access to its sole filtering function to also allow its use from a continuous network. It will also include an output to redistribute directly, possibly after amplification, this supply voltage 115V / 400Hz to a control unit 50 of another double seat. The DC voltage at the output of the circuit 51 is then regulated at the level of a power supply card 52 which develops the voltages necessary for the entire actuation system. It is a voltage of 5 volts DC for the power supply of electronic circuits (or even the lighting of keyboards), a voltage of 12 volts DC for the power of memory card readers, and d '' a voltage of 35 volts DC to power the actuators. Other voltages can obviously be provided according to the needs. This box 50 also includes a processing card 53 which manages the entire actuation system, that is to say which makes the connection between the orders of the passenger passengers (decoding of the data coming from the keyboards 20 or reading of the memory card reader data 21) and actuator control. This card which conventionally includes (see FIG. 5) a microcontroller comprising a program memory integrated or not and associated with a programmable logic circuit (of the FPGA or EPLD type for example) control, through two input-output cards of power 54, 55 (one per seat 10A, 10B), the different actuators. Of course, the aforementioned number of cards is not limiting and it is entirely possible to envisage ordering a single card or more than two cards (for example one per actuator). The processing card 53 also receives, via these input-output cards, position information from all or part of these actuators. Each input-output card is designed to be connected, in the example illustrated, to five actuators, without of course that this number is in no way limiting, three of these actuators being for example controlled in closed loop (with information of position back) and can be ordered simultaneously, the other two being controlled in open loop (without feedback information). The simultaneous control of the actuators is made possible by the microcontroller which sequences the starting of the DC motors to be actuated simultaneously to avoid that the starting current demanded by these motors when they are energized does not overload the system. However, this sequencing is not perceptible by the user because in practice the starting phase of DC motors lasts only a few tens of milliseconds. The connection between the box 50 and the data input means 20, 21 is provided by an internal bus 60 (a serial link of the ICC or RS232 type for example) which directly links the processing card 53 to these data input means 20, 21. In the example illustrated, the serial information which passes over this link (conventionally in the form of a data-address set) is firstly directed to the keyboards 20A, 20B then retransmitted, after verification of the communication protocol in a control module 61 of these keyboards, to memory card readers 21 A, 21B. It will be noted that there is nothing to prevent the serial data transfer between the input means and the electronic unit to be carried out by a fiber optic link, or even by a wireless link, by infrared or ultrasound for example. When the connection between the box 50 and the input means 20, 21 is carried out by an ICC type bus, it may be advantageous to provide a conversion interface means 27 to connect this box to other equipment of the seat, such as the communication means 17, audio-video listening means 18 or display means 19. In fact, it is thus possible to link these devices together by means of a serial link of RS 232 type (less specialized and as soon during management simpler than an ICC bus), the converter circuit 27 carrying out an adaptation of the specific communication protocol ICC to the RS 232 protocol. Of course, such a conversion means can also be envisaged with other types of protocol subject to to plan the necessary adaptations. It will also be noted that it is possible by this link to organize the different double seats in the network to allow for example a common programming in a maintenance phase, even during the flight. To do this, a network interface module 28 disposed between the serial link 60 and an external bus 30 connecting all the seats together, is provided at each double seat. These modules can be controlled from a specific unit (a PC-type microcomputer or the like not shown) or else directly by the control box 50 to which an external keyboard 29 will be added. Obviously, the microcontroller proceeds to reading of input data by successive scanning of keyboards and memory card readers and it is able to manage different priority levels.

It is important to note that the structure described with regard to this FIG. 4 is in no way limiting and that it is possible to envisage controlling the actuators of each seat at the level of a separate processing card. Similarly, it can be envisaged, in particular for test and maintenance questions, to use the external keyboard 29 as a maintenance keyboard by providing it with an integrated card reader. Centralized management around the microcontroller makes it possible to supervise the communication with users (via keyboards and memory card readers) and controlling the seat elements, but also managing the various safety devices (see more about checking the motor current) and ensuring test functions and seat maintenance and programming functions. In fact, the configuration of the processing card with its internal memory allows the positions of each actuator to be memorized from the keyboard and the recall of these positions at the request of the user. These positions can also advantageously be memorized at the level of a memory card of the user who can then write there the adjustment which suits him best for a type of seat. If he changes places (or during a next flight by the same company for example) he can instantly find, by inserting his personal card in the card reader of his new seat, this previously preprogrammed position. It will also be noted, and this aspect is an important element of the invention, that the memory card, or smart card, because of the high memory capacity which it possesses, offers possibilities of use for maintenance purposes. and very interesting test. It allows by direct dialogue with the microcontroller (the dialogue being managed at the level of the program memory of the microcontroller) the development of test diagnostics (identification of faulty actuators) for all the actuators of the double seat and above all it allows a programming of each of the electric strokes (the two extreme positions) of the actuators. Thus, at the manufacturing stage, after mounting the actuation system in each seat, it is possible using a specific card (for example a "configuration card") to inform the control unit 50 on the hardware configuration of the double seat, specifying the number of actuators installed, the value of the maximum current admissible by these actuators and the desired dl / dt value (the value of this parameter will be explained further). Of course, these parameters will have been previously introduced into this card by the seat manufacturer using any suitable writing (programming) device. It will be noted that the card can be read directly by one of the two card readers 21 from the seat or else introduced for reading at the level of the reader integrated into the external keyboard 29 and that this programming of the hardware configuration characteristics of the seats can be carried out directly in one only once for all of the seats because of their possible connection through the network 30. Similarly, it can be advantageously envisaged by means of a second specific card (for example a “stop adjustment card”) to define the extreme positions (limit stops) of each of these actuators. It suffices for this, this card having been previously introduced into a reader 21 or 29, to fix by the keys 32 to 36 the positions of maximum displacement (obviously within the limits of the mechanical stops) of each actuator 22 to 26 by means of the keyboard 20 or 29, do the same with the predefined positions 37 to 39, then by the action of the key 40 to memorize these positions at the level of the microcontroller 53 as well as at the level of this stop adjustment card which can then be removed . The adjustment of the other seats is then carried out simply by a new introduction of this card thus programmed in the corresponding readers then by the successive action of the recall 41 and memory 40 keys of the seats concerned. A single simultaneous programming of all these other seats 30 is of course possible through the network. This particular procedure of the invention avoids manual adjustment of the two limit switches of each actuator (ie 20 adjustments per double seat comprising 10 actuators) as is currently practiced.

The presence of at least one memory card reader at the actuation system according to the invention also makes it possible to offer user passengers a set of new services in connection with the communication means 17 or the display means. 19 present on the seat. It is thus for example possible to envisage allowing the microcontroller to validate the access to paid services after a certain debit of unit of account of a preloaded electronic purse inserted in the card reader has been observed.

Likewise, the network connection of all the seats facilitates maintenance and test operations. Thus, all of the seats can be tested from a single microcomputer, or advantageously from the maintenance keyboard 29, this test could for example consist of a verification of the operation of each actuator over its entire travel (it will be noted that this test could be automated by the introduction of a specific “test” card). It also allows the user airline which so wishes to modify the deflections of the seat elements and thus to define according to their needs the space left to the user passenger. More particularly, in a situation of extreme emergency and in the case where the external bus 30 is connected to a console in the cockpit, it is possible to envisage imposing a determined position on all of the passengers (the right sitting position corresponding to the key 37 of the keyboard 20) by direct control of the seats from this cabin. Likewise, this centralized connection from the cabin makes it possible to envisage, in addition to the communication of information concerning the flight, the provision of common video or television programs and no longer of individual films from prerecorded programs. Connection with telecommunications or computer networks external to the aircraft can also be envisaged directly from the seat of each passenger.

FIG. 5 very schematically shows the essential elements of the control of a first type of actuator 80 with position copying implemented in the actuation system of the invention. There are of course the circuits described above, the keyboard 20, the chip card reader 21, the processing card 53 and the power input-output card, for example 54. This input-output card 54 comprises in particular a relay 70 and a power switching element such as a MOS transistor 72 placed in series with a measurement resistor 74 in the control line of the actuator 80. An amplifier 76 makes it possible to amplify the voltage measured across the terminals of the measuring resistance and which is proportional to the current absorbed by the DC motor of the actuator. This amplified voltage is directed at the processing card to an analog-to-digital converter which supplies this current information to the microcontroller for its management. The latter can thus automatically control the shutdown of the actuator if the measured current exceeds a predefined maximum current previously entered into the microcontroller from the configuration card. The microcontroller takes care to switch the relay 70 to no load and the transistor 72 to load. Thus, when the actuator 80 is controlled, the relay is first closed, then the transistor is switched on, while when the power supply to this actuator is switched off, the transistor is first switched off, then the relay is opened. The measurement in real time of the motor current is very important because it makes it possible to evaluate the value of its derivative dl / dt and therefore to detect any accidental overload of the motor, for example when an unwanted obstacle is on the movement of the actuator. In this case, it will be noted that the microcontroller automatically orders a movement of the actuator, in the opposite direction, over a determined distance and if necessary it can order the stopping of the motor control. In an extreme case, the faulty actuator can be definitively put out of circuit. Likewise, software means 53 are provided at the level of the microcontroller which make it possible to disconnect one of the two seats from a double seat, momentarily switching off all the actuators of this seat, when a simultaneous control of all the actuators of the double seat, which is likely to cause an overload of power at the 115V / 400Hz network, that is to say in practice of consuming a power exceeding a predetermined threshold, is requested.

FIG. 6 shows in a simplified manner an example of the first type of actuator 80 of a seat element allowing in particular the control of the backrest, the seat or even the leg rest. This linear actuator comprises a body 81 secured to the seat structure, which is crossed by a reversible ball screw 82, each end of which is secured by support means 83 to a rack 84. The ball screw which has a much better efficiency than that of a conventional cut screw (about 0.85 instead of 0.35) and also has the advantage of allowing compensation for the loss of size (mass) resulting from the use of continuous motors, is in direct contact with a toothed wheel actuated by the DC motor 85 of this actuator and the rack is also in direct engagement with a means of potentiometric position copying 86. It will be noted that the screw-rack connection has the advantage of making it possible to move the actuator, in particular during its mounting in the seat, without risk of modifying the positioning of the potentiometric sensor 86 and therefore its own adjustment. Likewise, it is possible to change the linear speed of this actuator by a simple modification of the number of teeth of the toothed wheel. The command and control of this actuator is ensured from the control unit 50, as has been seen previously, by a connection cable 87 which carries the control signals (positive, negative and ground) and the control signals in return (in the case of the potentiometric sensor the positive and negative references and the midpoint voltage). The actuator body also comprises a declutching means 88 which makes it possible to separate the screw 82 from the motor 85 and therefore to manually control the movement of the seat element if necessary. An anchoring device 89 placed at one end of the ball screw is connected to the seat element to control its movement.

FIG. 7 shows another example of a second type of actuator 90 of a seat element more particularly intended for the adjustment of the lumbar part or of the headrest. This linear actuator of reduced size and weight (less than 300g for 100x90x35mm) mainly comprises a motor 91 whose output shaft comprises a worm gear part 92 which meshes directly with a toothed wheel 93, integral with a connecting shaft 94, which guarantees a minimum sound level. Furthermore, it is possible to change the linear speed of this actuator by a simple modification of the number of teeth of the toothed wheel. This connecting shaft has at its free end an anchoring device 95 connected to the seat element to be controlled. As before, the signals for controlling the rotation of the motor 91 are brought from the control box 50 by a connecting cable 96 which, however, in this case, does not carry return signals for the processing card. 53.

Claims

1. Seat element actuation system, each seat element (12, 13, 14, 15, 16) being movable by means of an individual actuator (22, 23, 24, 25, 26) controlled by from a centralized processing means (50) as a function of displacement positions defined by at least one data input means (20, 21, 29), a system characterized in that it comprises means (60, 29 , 30) making it possible to connect the centralized processing means (50) of a seat to at least one centralized processing means of another seat to allow joint movement of the actuators of these seats from any of the means entrance to these seats.

2. actuation system according to claim 1, characterized in that said connecting means between seats comprises an interface module (28) ensuring a connection between an external bus (30) connecting each double seat and an internal bus (60) of connection to centralized processing means (50).

3. Actuating system according to claim 2, characterized in that said internal and external bus comprise a serial link of the wired type, for example IIC or RS232, or a fiber optic link.

4. Actuation system according to claim 2, characterized in that said internal and external buses comprise a wireless infrared or ultrasonic link for example.

5. An actuation system according to claim 2, characterized in that said external bus is further connected to an external control unit of microcomputer type PC or the like.

6. Actuating system according to claim 2, characterized in that said external bus is also directly connected to a console of the cockpit.

7. actuation system according to claim 2, characterized in that it further comprises a converter means (27) disposed between the internal bus (60) and data output means (17, 18, 19) to ensure a conversion of a first communication protocol relating to the information circulating on the internal bus (30) into a second communication protocol compatible with these data output means.

8. Actuating system according to claim 1, characterized in that each individual actuator comprises a DC motor.

9. actuation system according to claim 8, characterized in that said centralized processing means (50) further comprises means (53, 54; 74, 76) for determining the variation in intensity of the current per unit of time (dl / dt) passing through the DC motor of each actuator and for controlling a short displacement of this actuator in the opposite direction, if this variation exceeds a predetermined threshold.

10. Actuating system according to claim 8, characterized in that said centralized processing means (50) comprises means (53, 54; 70, 72) for determining the maximum intensity of the current passing through the direct current motor of each actuator and to control the stopping of this actuator if this intensity exceeds a predetermined threshold.

11. Actuating system according to claim 8, characterized in that said centralized processing means (50) further comprises means (53, 54; 70, 72) for controlling the deactivation of an actuator determined in the event failure of this actuator, the other actuators remaining in service.

12. Actuation system according to claim 8, characterized in that said centralized processing means (50) further comprises means (53, 54; 70, 72) for temporarily switching off all of the actuators of a seat (10A or 10B) if, in the case of simultaneous control of all the actuators of a given double seat, the power consumed exceeds a predetermined threshold.

13. Actuation system according to claim 1, characterized in that said data input means is constituted by an external maintenance keyboard (29) advantageously provided with an integrated reader of memory cards.

14. Actuation system according to claim 1, characterized in that said data input means is constituted by a reader of memory cards or smart cards (21).

15. Actuating system according to claim 1, characterized in that it further comprises a first preprogrammed card (“configuration card”) in which the hardware configuration of the double seat is stored, for example the number of individual actuators or the maximum current intensity admissible by each of them, and which is intended to be read by said data input means to initialize said centralized processing means.

16. Actuation system according to claim 1, characterized in that it further comprises a second preprogrammed card ("card stop adjustment ”) in which the extreme positions of displacement of each actuator previously defined in a keyboard (20, 29) are memorized, and which can be read by any of said data input means to constitute data reusable by the seat manufacturer for automatic adjustment of the electric actuator strokes or their internal test.

17. Actuating system according to claim 1, characterized in that the actuators comprise an endless screw-toothed wheel assembly (82; 92,93) in direct engagement forming a single reducing stage.

18. Actuation system according to claim 1, characterized in that the actuators are provided with potentiometric type sensor means (86) delivering information proportional to the stroke of the actuator.

19. actuation system according to claim 18, characterized in that said sensor means cooperate with a rack (84) integral with the worm gear-toothed wheel assembly (82), so that the actuator can be moved , in particular during its mounting in the seat, without affecting the adjustment of these sensor means.

20. Application of the actuation system according to any one of claims 1 to 19 to a double seat, for example a double passenger first class or business class of an aircraft.