Abstract:
A table apparatus for a vehicle seat comprising a table, having at least one table leaf, and a table support mechanism, wherein the table support mechanism enables translational movement of the table between a substantially horizontal stowed configuration and a deployed configuration. In a preferred embodiment, the linkage arrangement of the table support mechanism comprises at least one substantially horizontally extending support arm extending from a table support member, the table being mounted upon a distal end of the support arm, the support arm being pivotally connected to the table support member for rotation about a first pivot axis in a substantially horizontal plane about the support member, the table being pivotally connected to said distal end of the support arm for rotation about a second pivot axis in a substantially horizontal plane, linkage means being provided for normally constraining rotational movement of the table about the second pivot axis to follow rotational movement of the support arm about the first pivot axis such that the rearmost table face remains substantially aligned to the user such that the table orientation is maintained substantially parallel to its final deployed position during movement between said stowed and deployed configurations.

Description:
This application is a 35 USC 371 National Phase filing of PCT/EP2008/004116 filed May 24, 2007, which claims the benefit of United Kingdom patent application 0709973.2, filed May 24, 2007, the disclosures of which are incorporated herein by reference in their entireties. 
     FIELD OF THE INVENTION 
     The present invention relates to a stowable table apparatus for a seat, and in particular to an in-seat table apparatus for vehicles and most particularly for aircraft. 
     BACKGROUND TO INVENTION 
     Conventional in-seat tables consist of bi-fold or single leaf tables, which are stored in an upright position, typically within a console or armrest to one side of the seat, and, in use, are translated and or rotated onto the required plane. Positioning relative to the passenger is achieved through the use of parallel slides and hinges. 
     However, the multiplicity of translational and rotational movements required for table deployment and stowage tend to overcomplicate and reduce the intuitiveness of such assemblies. It is considered therefore that increased intuitiveness embodied within the design will aid passenger comfort. The use of parallel slides for transactional movements may mean that the user has to support the table in two locations in order to ensure smooth movement. 
     Another problem with such designs is that the contained rigid mechanisms cause the table to interfere with passenger access and egress whilst the table is in the deployed state and the upright storage position can cause storage problems where space within the console is limited, or example due to installations within the console, or the need for access beneath the console, for example for the legs of a passenger in a seat behind. 
     SUMMARY OF THE INVENTION 
     According to the present invention there is provided a table apparatus for a vehicle seat comprising a table, having at least one table leaf, and a table support mechanism, wherein the table support mechanism enables translational movement of the table between a substantially horizontal stowed configuration and a deployed configuration. 
     Preferably the table support mechanism comprises a table support member and a linkage arrangement adapted to guide the translational movement of the table through an arc between said stowed configuration and at least a partly deployed configuration. More preferably the linkage arrangement of the table support mechanism is adapted to maintain the rearmost table face substantially aligned to the user such that the table orientation is maintained substantially parallel to its final deployed position during movement between said stowed and deployed configurations. 
     In a preferred embodiment, the linkage arrangement of the table support mechanism comprises at least one substantially horizontally extending support arm extending from the table support member, the table being mounted upon a distal end of the support arm, the support arm being pivotally connected to the table support member for rotation about a first pivot axis in a substantially horizontal plane, the table being pivotally connected to said distal end of the support arm for rotation about a second pivot axis in a substantially horizontal plane, linkage means being provided for normally constraining rotational movement of the table about the second pivot axis to follow rotational movement of the support arm about the first pivot axis such that a rearmost table face remains substantially aligned to the user such that the table orientation is maintained substantially parallel to its final deployed position during movement between said stowed and deployed configurations. Preferably the linkage means is arranged to permit at least limited independent rotation of the table with respect to the support arm about said second pivot axis at least when the table is in a partially deployed configuration to permit the table to be rotated to an out of use position to facilitate access to the seat. 
     In one embodiment, said linkage means comprises a guide link pivotally connected at one end to said support member at a location spaced from said first pivot axis and at an opposite end to said table at a location spaced from said second pivot axis, to extend substantially parallel to the support arm, whereby said support arm and guide arm are arranged in a parallelogram relationship for guiding movement of the table relative to the support member. Preferably said guide arm is arranged such that said first and second pivot axes are aligned with the pivot axes of the guide arm, connecting the guide arm to the support member and table respectively, when the table is in said partially deployed configuration to permit said independent rotation of said table. 
     In a alternative embodiment, the linkage means comprises a plurality of intermeshing gears rotatably mounted on said support arm comprising a first gear, said first gear being non-rotatably connected to said support member and centred about said first axis, a second gear, said second gear being non-rotatably connected to said table and centred about said second axis, and an odd number of intermediate gears extending between said first and second gear along the intervening length of the support arm, said intermediate gears constraining rotation of the second gear to follow rotation of the first gear. Preferably said second gear is mounted on said table to permit limited rotation of said second gear with respect to said table against a biasing force to permit limited independent rotation of the table away from the user about said second axis. 
     In a further alternative embodiment, the linkage means comprises a first pulley or sprocket rotatably mounted on one end of said support arm, centred about said first axis and non-rotatably connected to said support member, a second pulley or sprocket rotatably mounted on an opposite end of the support arm, centred about said second axis and non-rotatably connected to said table, and an endless belt or chain extending between said first and second pulleys constraining rotation of the second pulley or sprocket to follow rotation of the first pulley or sprocket. Preferably a tensioning means is provided for tensioning the belt or chain on one side of the support arm, said tensioning means including biasing means to take up any slack in the belt or chain on said side of the support arm, said tensioning means permitting limited rotation of said second pulley or sprocket with respect to the first pulley or sprocket against the biasing force of the biasing means to permit limited independent rotation of the table away from the user about said second axis. Alternatively at least a portion of the belt, arranged to be located on one side of the support arm, may comprise or incorporate a resilient section enabling elongation of said resilient section against a biasing return force, said resilient section being capable of elongation to permit limited rotation of said second pulley or sprocket with respect to the first pulley or sprocket against said biasing return force to permit limited independent rotation of the table away from the user about said second axis. 
     Preferably the table is arranged to be enclosed within a console to one side of the seat when it its stowed configuration. A latch means may be provided for retaining said table in said stowed configuration. A release mechanism, such as a manually operable button or switch, may be provided for selectively releasing said latch means to release the table from its stowed configuration. Preferably biasing means is provided for urging the table from its stowed configuration towards its deployed configuration upon actuation of the release mechanism. 
     Preferably the table support mechanism is arranged such that, when in its deployed configuration, the table is located at a raised position with respect to its stowed configuration. The table support member may be slidably mounted on a guide means for guiding movement of the table support member, and the table mounted thereon, between a first position at a first height and a second position at a second height, said second height being greater than said first height, during a transverse translational movement of the table support member with respect to the guide means. 
     In a preferred embodiment, the guide means comprises a pair of parallel guide blocks, said support member being slidably mounted between said parallel guide blocks, each guide block having at least one elongate guide channel or groove on a side face thereof facing said support member, said support member being provided with projecting follower members projecting from opposing first and second side walls of the support member to be received with respective guide channels of the guide blocks for guiding movement of the support member with respect to the guide blocks between a retracted lower position and an extended raised position. 
     Preferably each guide block is provided with first and second spaced guide channels, opposing sides of the support member being provided with corresponding first and second outwardly projecting follower members to be respectively receivable with said first and second guide channels. 
     In one embodiment, the support member extends from the guide blocks in cantilever fashion towards its extended raised position such that weight of the table exerts a moment about the first and second follower members, the first and second guide channels being configured such that, when the support member is in its extended raised position, the weight of the table exerts a moment about the first follower members to bias the second follower members towards an uppermost end of the respective second ends of the second guide channels, whereby the first follower members are biased towards an uppermost end region of the respective first channels, said uppermost end region of the respective first channels extending substantially horizontally such that the weight of the table acts to retain the support member in its extended raised position. 
     Preferably the guide channels of the guide means are configured such that, when the support member is in its retracted lower position, the relative positions of the respective guide channels of the guide blocks are arranged such that the table is arranged substantially horizontally, and, when the support member in its extended raised position, the relative positions of the respective guide channels of the guide blocks are arranged are arranged in a non-parallel manner such that the table is inclined with respect to the horizontal. Where the table is to be used with a seat for an aircraft, when the support member is in its raised extended position, the table is preferably inclined forwardly at an angle of approximately 3° to the horizontal to compensate for the pitch of the aircraft during normal flight. 
     Preferably the support member is biased towards its extended raised position by biasing means. In one embodiment, the biasing means comprises a overcentre mechanism such that, when the support member is in its retracted lower position, the biasing means acts in a direction to maintain the support member in said retracted lower position, and, as the support member is moved towards its extended raised position, the biasing means acts in a direction to urge the support member towards its extended raised position. 
     Accordingly, the invention provides an in-seat table apparatus comprising one or more table leafs that can be are stored in a horizontally related plane and may be secured in the stowed configuration using a suitable latch mechanism. The table can be moved to a fully deployed position by either pulling to the side or to the front of its stored location. Smooth operation is achieved by a using mechanism or plurality of mechanisms, such as two parallel links, gears or a chain/belt driven mechanism, that ensures the table travels upon a predetermined parallel path during deployment/stowing. The relationship between pivot positions and mechanism may be optimised depending on the users requirements primarily to ensure optimum table coverage over a specified distance. This design allows for simpler intuitive kinematics and in some cases a reduction in the number of components required. Over the specified usable distance, the table may be maintained parallel to the user. However, when the table is at least partially deployed, passenger egress and access can be improved by enabling the table to be pivoted independently, away from the seated position. 
     In one embodiment, the apparatus includes an actuation means which raises the intuitiveness by ‘presenting the table’ to the passenger. This initial presentation may perhaps be to a predetermined distance and occur at a controlled speed if required. 
     In one embodiment there is provided a mechanism for raising or lowering the table to a predetermined height with the ability to ‘lock’ the table in position by utilising the weight of the assembled components. Dependant upon the size or weight of the table, or indeed end user needs, the operation may be assisted by an actuation means. Therefore raising and lowering the table can be one-handed operations whereby the table can easily be pulled along a predetermined path to its final resting position. The table can only be released from this position by raising the edge that is furthest from the point of rotation until the table is in essence weightless. Again the table returns along a predetermined, definable path. Separately this mechanism may also incorporate a resilient return device which will aid deployment. 
     In one embodiment, the table can start at one plane for example parallel to the floor and finish at a different angle if required. The definable path becomes 3 dimensional in that the path followed may move along the X, Y and Z-axis whilst finishing at a planar angle that is different to the initial. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a seat embodying the invention. 
         FIG. 2  is a schematic top view of the invention with the table stowed. 
         FIG. 3  is a schematic bottom view of the invention with the table stowed 
         FIG. 4  is a schematic view of the invention incorporating a different mechanism type. 
         FIG. 5  is a schematic view of the mechanism incorporating a different mechanism type. 
         FIG. 6  is a schematic view of the mechanism incorporating a different mechanism type. 
         FIG. 7  is a perspective view of the invention with the table in the initially presented state. 
         FIG. 8  is a schematic front view of the invention with the table in the lowest vertical position. 
         FIG. 9  is a perspective view of the table partially raised and fully deployed. 
         FIG. 10  is a schematic side view of the table fully raised, tilted and fully deployed. 
         FIG. 11  is a schematic top view of the table in a position suitable for someone of larger build. 
         FIG. 12  is a schematic top view of the table in a position suitable for someone of medium build. 
         FIG. 13  is a schematic top view of the table in a position suitable for someone of small build. 
         FIG. 14  is a schematic top view of the table in the over centre position allowing egress/access to the passenger place. 
         FIG. 15  is a schematic top view of the table in the ‘rotated’ position increasing egress. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a perspective view of a table  11  embodied within a suitable cosmetic shroud, typically comprising a console  1  located alongside a seat  2 , typically a business class airline seat. Supporting structures have been removed for clarity of view. In the position shown in  FIG. 1 , the table  11  is stowed horizontally, parallel to and beneath a horizontal upper surface of the console  1  within an upper region of the console  1 . 
     As illustrated in  FIG. 2 , whilst in the stowed position, the table  11  can be secured, if required, by a suitable latch mechanism  12 . The table  11  is connected to the console/seat assembly by linkage means providing guided movement of the table  11  between stowed and operative positions, as will be described below. In the stowed position the deployment actuation means  17 , comprising a biasing means biasing the table towards an extended or operative deployed position, is compressed between its fixed mount and the rear table face, the table  11  being maintained in the stowed position by the latch mechanism  12 . A release mechanism  22  is provided, comprising a button or switch, for releasing the latch mechanism  12  to deploy the table from its stowed position. 
     As shown in  FIG. 3 , the linkage means comprise a load-carrying link  23  for supporting the table, pivotally connected between the table  11 , under the table surface, and a table carrying arm  28 . A guide link  27  is also pivotally mounted between the table carrying arm  28  and table  11  to extend parallel to the load-carrying link  23 . The relationship between the links  23 ,  27  and their associated pivot points  41 ,  42 ,  43 ,  44  provides a parallelogram mechanism that controls the travel path and useable section of table travel. It is this mechanism that maintains the rearmost table face  11  aligned at the required angle to the user (whilst deploying, in-use and stowed). In the example given the table could be considered parallel to the user. 
     The design of the mechanism is such that the table can deployed to a range of positions distance allowing for people of different builds, for example.  FIG. 11  depicts the table in use by someone of larger build. To reach this position, the passenger pulls the table  11  along a controlled arcuate path from the initially deployed state to the position shown in  FIG. 5 . During this motion, the links  23 ,  27  rotate in a controlled parallel state by rotating at their ends around the relative pivot points  41 ,  42 ,  43 ,  44 . 
       FIG. 12  depicts the table position for someone of medium build. This position is reached by pulling the table  11  towards the user. The parallel links  23 ,  27  rotate further, whilst controlling the angle between the user and the table edges. 
       FIG. 13  depicts the table position for someone of slight build. This position is reached by pulling the table  11  towards the user. The parallel links  23 ,  27  rotate further, whilst controlling the angle between the user and the table edges. As shown in  FIGS. 5 ,  6  and  7 —the mechanism allows a controlled, predetermined useable table range of movement to be defined through specification. 
     In order to ease access and egress for the passenger, it is desirable for the table to be rotated away from the passenger. In this embodiment, the rotation is only achievable at a specific, controlled location that is determined by the relationship between the table  11  and link pivots  41 ,  42 ,  43 ,  44 . In order to use this functionality the table must be in a position where the link pivot points  41 ,  42 ,  43 ,  44  are aligned along a single plane that runs parallel to and through the pivot  41 ,  42 ,  43 ,  44  axes as shown in  FIG. 14 . 
     When this position is reached, the table  11  may pivot independently and thus rotate away from the user creating an open space as shown in  FIG. 15 . This space can then be utilised for access and egress. 
     As shown in  FIG. 4 , in an alternative embodiment, the plurality of parallel links can be replaced by a system of interacting gears  50 - 54 . A first gear  50  is rigidly fixed to a table carrying arm  56 . Gears  51 - 53  are free to rotate around respective axes through their centres. A further gear  54  is rigidly fixed to the table  11  except in the case where the design requirement specifies that the user must be able to pivot the table away from them in order to improve egress. In this case the design can incorporate a resilient return device or mechanical interaction which replaces said rigid joint between table  11  and gear  54 . Supporting structures have been removed for clarity of view. 
       FIG. 5  shows a further embodiment, wherein the plurality of links are replaced by a belt system  63 , which may be toothed or otherwise. A first pulley  60  is rigidly fixed to the seat structure, such as the table carrier arm  56 . A second pulley  61  is rigidly fixed to the table  11 , except in the case where the design requirement specifies that the user must be able to pivot the table away from them in order to improve egress. In this case the design can incorporate a resilient return device or mechanical lock, the latter replacing said rigid joint between table  11  and second pulley  61 . The resilient return device may be used to pretension the belt  63  and overriding the device will allow the table  11  to be pivoted away from the passenger space about the axis of the second pullet  61 . Supporting structures and tensioning device have been removed for clarity of view. 
       FIG. 6  shows a further embodiment, wherein the plurality of links are replaced with a chain and sprocket system. A first toothed sprocket  70  is rigidly fixed to the seat structure or pivot arm  56 . A roller chain  73  meshes with and extends between the first toothed sprocket  70  and a second toothed sprocket  71  which is rigidly fixed to the table  11  to maintain the ‘parallel’ relationship between the table  11  and the front of the seat  2 . 
     In this embodiment, the design can incorporate a resilient return device or mechanical lock, the latter replacing said rigid joint between table  11  and the second toothed sprocket  71 . The resilient return device  72  may be used to pretension the chain  73  and overriding the device will allow the table  11  to be pivoted away from the passenger space. Alternatively the resilient return device may be joined directly to the chain—effectively acting as a resilient chain link. Supporting structures have been removed for clarity of view. 
     In each case, the linkage means provides a controlled movement of the table  11  in a substantially horizontal plane between a stowed position and an extended operative position in a substantially circular motion with the table being maintained in parallel relationship to the front edge of the seat  2 . 
     In use, the table  11  is released by activating the release mechanism such as but not solely limited to a button or lever  22  (see  FIG. 7 ). After the table has been released, it travels to an initial presentation point shown in  FIG. 7  under the action of the actuation means  17 . The load and travel of the actuation means  17  controls the distance and speed of deployment over this initial section. The table  11  travels along a path that is controlled by the linkage means, such as parallel links  23 ,  27 , resulting in the table following a defined path. 
     The linkage mechanism is also adapted to enable the table to be raised from a lowered position at a first height, wherein the table is receivable within the console  1  in its stowed position, and a raised position at a second height, above the first height, wherein the table is at a convenient height for use by a passenger seated in the seat  2 . In order to achieve this movement, the table carrying arm  28 , 56  upon which the table is supported is located between a pair of parallel guide blocks  15 , 16 , each guide block  15 , 16  having spaced guide channels  30 , 32  within which are received respective follower members  34 , 36  extending from the sides of the table carrying arm  28 , 56 , the guide channels  30 , 32  defining a guide path whereby the table carrying arm  28 , 56  moves in a vertical direction as the follower members  34 , 36  move along the guide channels  30 , 32 . The guide channels  30 , 32  are arranged such that the table  11  is located parallel to the upper surface of the console  1  when it its lowered position and the table  11  is inclined forwardly to compensate for the normal flight pitch of the aircraft when in its raised position, as illustrated in  FIG. 10 . This is achieved by arranging the guide channels  30 , 32  of one guide block  15  being non-parallel to the guide channels of the other guide block  16  such that the table carrying arm  28 , 56  is effectively rotated as it moves along the guide channels  30 , 32 . 
       FIG. 8  shows a front view of the table  11  and the swarfing (a controlled path defined as a helix guided in 3 planes at an infinite number of locations) guide blocks  15 , 16 . The angle between the table surface and perhaps the floor may be 0 degrees (as depicted) whilst in the stowed position. The angle required at the deployed position is a designed function of the swarfing channels  30 , 32  contained within said swarfing blocks  15 ,  16 , whereby the angle of the table carrying arm  28 , 56  varies as the followers  34 , 36  of the arm  28 , 56  move along the guide channels. 
     To increase the deployed height of the table, the user may raise the table  11  by pulling the table  11  along the path defined by the guide channels  30 , 32 .  FIG. 9  is a schematic perspective view of the table  11  partially raised, indicating the new position of the table carrier arms  28 , 56  within the channels  30 , 32 . The shape of the channels  30 , 32  controls the rate of change in X, Y and Z along with the rate of angular change. 
     In the fully deployed state shown in  FIG. 10  the table  11  is at its raised position and, depending upon specified requirements, may be tilted relative to the floor. The tilt is achieved by varying the 3 dimensional relationship between the channels  30 , 32  contained within the respective swarfing blocks  15 ,  16 . 
     The uppermost end regions of the guide channels  30 , 32  are adapted such that the weight of the table  11  acting on the lever arm defined by the table carrying arm  28 , 56  and the linkage means extending laterally therefrom maintains the table  11  in its raised position until the table  11  is lifted to allow the follower members  34 , 36  to slide back down the guide channels  30 , 32 . This is achieved by the arrangement shown in  FIG. 8 , whereby, in each guide block  15 , 16 , a first guide channel  30  closest to the seat  2  has a horizontally extending end portion while a second guide channel  32  furthest from the seat  2  has an upwardly inclined end portion, such that the weight of the table  11  causes a moment to be applied about the table carrying arm  28 , 56  acting around the horizontally extending end portion of the first channels  30  to urge the followers  36  towards the upwardly inclined end portion of the second channels  32 , in turn pushing the followers  34  into the horizontally arranged end portions of the first channels  30 . To lower the table, a lifting action must be applied to the table  11 , causing an opposite moment to be applied about the table carrying arm  28 , 56  acting around the horizontally extending end portions of the first channels  30  to urge the respective followers  36  away from the upwardly inclined end portions of the second channels  32  to in turn release the respective followers  34  from the horizontally extending end portions of the first guide channels  30 . 
     A biasing means, such as a compression spring or gas strut (not shown) may act upon the table carrying arm  28 , 56  to urge the table carrying arm along the guide channels  30 , 32  towards its raised position. Preferably the biasing means is mounted at a position on the guide blocks  15 , 16  or an adjacent structure to provide an over centre action. 
     The invention is not limited to the embodiments described herein but can be amended or modified without departing from the scope of the present invention.