Patent Publication Number: US-2003230917-A1

Title: Contour-adjustable seat and modular support unit

Description:
BACKGROUND OF THE INVENTION  
       [0001] The invention relates to a contour-adjustable seat, particularly a vehicle or aircraft seat, having a backrest and possibly lateral support pieces whereby there are gas or air-inflatable cushions provided on a common flexible modular support unit, possibly designed as a separate component, whereby the modular support unit serves as a common support surface for the cushions, which are each connected to a source of compressed air or gas via a line provided with a controllable valve, whereby each valve communicates with a control unit for air or gas pressure via a control line. A pressure sensor is provided for each cushion as well as a modular support unit is provided for a seat of this type having a backrest section and possibly lateral support sections whereby air or gas-inflatable cushions are provided on or on top of the modular support unit.  
       [0002] It is generally known to provide one or a plurality of cushions, which are inflatable with air or other gases, especially on the backrest of seats to obtain a fit to the shape of a sitting person. Less tiring and more comfortable sitting over a long period is made possible—in case of vehicle seats, driving over a long period is less tiring and more comfortable—and in case of furnished lateral support pieces, there is also improved support (stability) when driving around curves. Up to now, individual cushions are separately mounted on the seat in a costly manner and each cushion is connected to a compressed air supply and to a pressure control element, as it is described in DE 38 04 959 C2, for example. The air pockets in the seat are supplied with air through an air line leading to the pockets and via a control device having a number of solenoid valves, which is arranged under the seat, for example. The control device contains the pressure sensor mechanism as well. A similar system is also disclosed in EP 1 072 465 A2. This external valve and control box is relatively heavy, requires considerable structural space and the seat has an unfavorable bulky shape based on the type of design of a seat having separate cushions.  
       [0003] DE 41 06 862 A1, DE 41 06 863 A1, U.S. Pat. No. 3,326,601 A and DE 37 35 428 A2 are described as having gas or air-inflatable cushions provided on a common support element. The modular support unit proposed in these constructions also forms a common support surface for a plurality of cushions.  
       [0004] It was therefore the object of the invention to find a system which is simple in construction of the seat, which is also well-suited for possible retrofitting, and which subsequently requires less space and is lighter than conventional systems.  
       [0005] For achievement of this object, a seat as described above is characterized, according to the invention, in that additional components for the contour adjustment system are integrated in the modular support unit, e.g. valves for cushions and/or for pressure sensors. Additional simplifications can be achieved, in a simple and time-saving way, in construction and assembly as well as improvements relative to the necessary structural space (dimensions) in case of cushions, which are installed as a unit, which have a defined position to one another, and for which no detrimental shifting of faulty installation can occur.  
       [0006] The object in the invention is also achieved through a modular support unit for air-inflatable cushions, characterized in that the cushions are provided on common flexible sheeting whereby the sheeting serves as a common support surface for the cushions.  
       [0007] The cushions are formed by air pockets between two pieces of sheeting bonded to one another, preferably fusion-welded (bonded) pieces of sheeting, whereby the shape and dimension of the air cushions can be determined in a simple manner, which also deviates from the traditional bulky shape.  
       [0008] According to an advantageous embodiment of the invention, the lines to the cushions are also formed by openings in the bond of the two pieces of sheeting. Manufacturing, installation and assembly is thereby simplified even further since the necessary lines for air or fill-gas, for example, are automatically connected properly.  
       [0009] It is preferably proposed thereby that the lines to the cushions start at a common connection point on the modular support unit. Only a single compressed air or compressed gas connection is to be provided on the modular support element and thus on the seat itself.  
       [0010] If there are also valves for the cushions attached to the modular support unit, as it is the case according to an additional characteristic of the invention, then all costs for an external valve subassembly can be avoided and the necessary structural space can be further reduced. Error is connecting the line can be avoided as well.  
       [0011] Two valves are preferably fusion-welded thereby between the pieces of sheeting and they are thus protectively integrated in the modular support unit whereby the risk is eliminated that connections between the valves and the lines can become unintentionally detached.  
       [0012] An additional advantage relative to the simplified assembly and installation can be obtained in that pressure sensors for cushions are attached to the modular support unit. Thereby, an external control device can also be avoided in this area or it may be designed having considerably smaller dimensions.  
       [0013] The advantage of protection for the components and the possibly best, non-detachable connection can also be realized here if the pressure sensors are fusion-welded between the pieces of sheeting.  
       [0014] The modular support unit requires the least structural space if it is designed according to an additional characteristic of the invention whereby the pressure sensors are integrated in the valves.  
       [0015] It is advantageously proposed thereby that the valves are designed as piezo-valves whereby very quickly and accurately operating valves having small dimensions can be realized.  
       [0016] In the following description, the invention is described in more detail with the aid of a preferred embodiment example relating to accompanying drawings. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0017]FIG. 1 shows thereby a seat for a motor vehicle as a special embodiment example whereby the seat is equipped with a modular support unit with air-inflatable cushions, and  
     [0018]FIG. 2 is a larger view of the modular support element itself. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0019]FIG. 1 shows a vehicle seat F which is provided with a seating element  1 , a backrest  2  and a headrest  3 . Lateral support pieces  4  may be provided on the backrest  2  to give improved lateral support, particularly when driving in a curve. The seat F has additionally a pneumatic system to be able to alter the contour of the backrest. A plurality of air-inflatable cushions  5   a ,  5   b ,  5   c  are provided for this purpose, of which three cushions  5   a  are arranged in the lordosis (lumbar) region, for example, directly above the seating element  1 . Cushions  5   b  for further improvement or fit for lateral support may be provided in the lateral support pieces  4  of the seat F, and an additional cushion  5   c  may be provided in the upper area of the backrest  2  as well.  
     [0020] The cushions  5   a ,  5   b ,  5   c  are supplied with compressed air from a compressed air source (not illustrated) and the valves for cushions are also provided with control signals via a central pneumatic and electric/electronic interface element  6 . An operating unit  7  allows the user to fittingly adjust the size of the cushions  5   a ,  5   b ,  5   c  in concert or relative to one another.  
     [0021] As it can be seen now in detail in FIG. 2, the air or gas-inflatable cushions  5   a ,  5   b ,  5   c  are formed as air pockets in a common modular support unit M whereby the modular support unit M is installed as one component in the final assembly or also during possible retrofitting of the seat F.  
     [0022] The air pockets  5   a ,  5   b ,  5   c  are formed by the non-bonded areas between two pieces of sheeting, preferably PU (polyurethane) sheeting, which are connected to one another and of which the modular support unit is made. Different welding (bonding) processes can be used for this purpose. Through fusion-welding of the pieces of sheeting  8  to one another, there can be created additional cavities, comparable to conduit strips on an electronic circuit board, which serve as air supply and discharge lines  9 . The pieces of sheeting  8  of the modular support unit M are advantageously designed having a different thickness in material in specific areas whereby the shape and development of air pockets  5   a ,  5   b ,  5   c  can be influenced. Furthermore, a more uniform dispersion in strength can be furnished by a plurality of cells within the air pockets  5   a ,  5   b ,  5   c.    
     [0023] Additionally, the valves  10  are advantageously fusion-welded between the pieces of sheeting  8  and are attached thereby next to the air pockets  5   a ,  5   b ,  5   c  whereby the valves are necessary for the control of the air pockets  5   a ,  5   b ,  5   c . A flat cable  11  may be fusion-welded either on the modular support unit M itself or again between its pieces of sheeting  8 . Diverse plug-in connectors may be provided which guarantee electric power supply for the valves  10 . Electric and pneumatic elements can then be connected via a common connection  12  to the interface element  6  for electric power or compressed air  13 .  
     [0024] The valves  10  on the modular support unit M are advantageously designed as small-constructed piezo-valves, which are thereby simply integrated in the modular support unit M and with which quick and accurate switching is made possible in terms of time.  
     [0025] The pressure sensors are now also integrated in the modular support unit M instead of being together with the valves in one central control box as before, whereby said pressure sensors are integrated preferably directly in the valves  10 . Thus, only one pneumatic supply and discharge line  14  and one electric supply (line)  15  are necessary, regardless of how many air pockets  5   a ,  5   b ,  5   c  exist in the seat F. The pressure sensors in the valves  10  can thereby be designed to be very simple if the pressure signals are evaluated in the electronic circuit integrated in the interface element  6  with the aid of deposited (stored) calibration data and forwarded to the electronics of the vehicle. The calibration data of the respective valves  10  are determined at initial installation of the system, for example. Only one highly precise pressure sensor is provided for this purpose in the interface element  6 , which can output standardized data. It is possible to use these simple pressure sensors in the valves  10  with this combination, which can deliver no usable data by themselves. The interface element  6  and the valves  10  are fed a supply of air. All valves are opened during a calibration process. A constant pressure is thereby established in the system. The values of the simple sensors in the modular support unit M are now adjusted to the ones of the reference sensor in the interface element  6  and the respective data is stored.  
     [0026] Of course, there could be at least one more piece of sheeting fusion-welded instead of only two pieces of sheeting  8  so that additional functionalities could be offered—for example, a rather point-massaging air pocket running approximately along the (human) spine region. The additional piece of sheeting is preferably attached to the back of the modular support unit M.