Abstract:
This invention relates to a tensioning device ( 40 ) for pulling a cover ( 18 ) of an interior fitting ( 1100 ), particularly a seat ( 1110 ), into a trench ( 27 ′). 
     The invention provides for the tensioning device ( 40 ) to have at least one tension-transmission device ( 28 ) for transmitting tensile forces between the interior of the seat ( 1110 ) and the cover ( 18 ), at least one anchorage device ( 29 ) for fastening the cover ( 18 ) directly or indirectly to a cushion and/or the seat ( 1110 ), at least one stiffening element ( 9 ) for distributing tensile forces of the tension-transmission device ( 28 ) uniformly along the pulled-down cover ( 18 ), and/or a pressure-distribution device ( 33 ) to prevent a concentration of pressure caused by the tensioning device ( 40 ) on the functional elements ( 1 ) within the seat.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The subject matter of this invention includes an air-conditioned seat with trenches and a tensioning device therefore. 
       SUBJECT OF THE INVENTION 
       [0002]    Stitched seat covers on air-conditioned seats or other seating furniture with air-ducting layers in the area of the seat or backrest-contact surfaces are often problematic in that the air-conditioning in areas of a seat or backrest surface that are separated from one another by stitching is non-uniform due to insufficient airflow continuity across the seat-cover trenches. 
         [0003]    Difficulties are also frequently encountered in realizing 90° angles and smooth cushion edges with known spacer media, so that trenches and cover edges formed by spacer media are not always of neat appearance. It is common practice—as described, for example, in DE 10037065—to use knitted spacer fabrics only in trench-free seat areas, and to separately ventilate, for example by means of mini-fans, each of those seat-area surfaces that are separated from one another by trenches. 
         [0004]    If air-ducting layers are nevertheless spanned, for example by point wise anchorage, this often reduces the ventilation efficiency, leads to an unattractive appearance due to differences in trench depth, and/or reduces the service life of electrical components (e.g. the seat heating) near to the surface as a result of increased stress. 
         [0005]    One objective of this invention is thus to provide an air-conditioned seat with at least one cushion layer that is sub-divided by optically and haptically acceptable stitching, and to ensure a uniform and sufficient air supply to all of the air-ducting layers beneath the seat&#39;s cover fabric while keeping the construction as uncomplicated as possible. In particular, the invention is intended to ensure that the airflow continuity across the seat-cover trenches is good enough to enable a single ventilation device to ventilate all areas of the seat. 
         [0006]    This objective of the invention is established with the subject matter of the independent claims  1  and/or  2 . Features of useful developments of the invention are evident from the dependent claims and the following description. 
         [0007]    The invention permits the use of standardized air-conditioning modules by providing for adaptation to the respective seat design. It also reduces production times and costs, increases the service life of surface-near functional components, and improves the appearance of the seat by way of taut, uniform seams and contours. An arrangement of this kind also makes it possible to route the lines for electrical or fluidic functional components, especially seat-heating, seat-occupied-recognition, pneumatic-seat-adjustment or seat-cooling components, through the recess  27 /the tensioning device  40 . 
     
    
     
       DRAWINGS 
         [0008]    Details of the invention are explained in the following. These explanations are intended to elucidate the invention. However, they are only of exemplary nature. The scope of the invention naturally allows for one or more of the described features to be omitted, modified or augmented. And it goes without saying that the features of different embodiments can be combined with each other. What is crucial is that the idea behind the invention is essentially implemented. The term “essentially” means that a particular feature (e.g. of the claims) is implemented to an extent of at least 50%, preferably at least 90%, preferably at least 95% or 99%. 
           [0009]    Reference will be made hereinafter to: 
           [0010]      FIG. 1  A motor vehicle, partially in longitudinal section 
           [0011]      FIG. 2  A longitudinal section through the trench of a seat cushion for the vehicle shown in  FIG. 1 , in the area denoted by A 
           [0012]      FIG. 3  A first embodiment of a tensioning device with nonwoven fabric and plastic strips 
           [0013]      FIG. 4  A second embodiment of a tensioning device configured as a plastic profile 
           [0014]      FIG. 5  A third embodiment of a tensioning device configured as a wire bow with w-shaped bends 
           [0015]      FIG. 6  A fourth embodiment of a tensioning device configured as a wire bow in a tube of non-woven fabric 
           [0016]      FIG. 7  A fifth embodiment of a tensioning device, analogous to  FIG. 6  but with an additional reinforcing member along the edge of a tape or a tube 
           [0017]      FIG. 8  A sixth embodiment of a tensioning device, analogous to  FIG. 6  but configured as a wire frame instead of a tube. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0018]      FIG. 1  shows a vehicle  1000 . The vehicle can be, for example, an airplane, a rail vehicle, a ship, or, as here, a motor vehicle. 
         [0019]    The vehicle  1000  has at least one interior fitting  1100 . In case of doubt, interior fittings are defined as all those components with which a user of the passenger compartment can come into contact, such as a steering device for the vehicle, a dashboard, an armrest, a door-trim panel, a seat pad, an electric blanket, a roof lining, a cushion  400 , a cover  18  or, as here, a seat  1110 . 
         [0020]    The interior fitting  1100  preferably has at least one cushion  400  and/or at least one cover  18 . 
         [0021]    The interior fitting  1100  preferably includes at least one climate-conditioning system  100 . This serves, for example, for the temperature control or air conditioning of user-contact surfaces in the passenger compartment of a vehicle. The device has at least one temperature-control means  110 , at least one air-ducting means  120  and/or at least one moisture-regulating means  130 . The term “temperature-control means” refers to any means that can be used to selectively alter the temperature of its surroundings, e.g. all devices having at least one electrical heating resistor, a heat pump, a Peltier element and/or an air-movement means such as a fan, or that is comprised essentially thereof. The term “air-movement means” refers to any means that can be used to selectively alter the air composition or the airflows in a given surface or spatial area by way of air exchange, e.g. an on-board air-conditioning system, at least partially air-permeable spacer media, knitted spacer fabrics and/or an air-conditioning insert. The term “moisture-regulating means” refers to a means for regulating the humidity of its surroundings, especially the temperature-control means already mentioned and moisture-absorbing substances such as activated carbon fibers and polymeric super absorbers. 
         [0022]    A seat  1110  has at least one recess  27 . This takes the form of a trench  27 ′. The trench  27 ′ is at least partially covered by a cover  18 , which is pulled into the trench  27 ′ by a tensioning device  40 . 
         [0023]    Beneath the cover  18 , a backing  20 —for example a foam backing—is provided on both sides of the trench  27 ′. Above the trench  27 ′ itself, this backing  20  is at least partially perforated, replaced by a thin material, omitted and/or engineered to be thinner. In this way, a visible trench is formed in the upper seat surface even if there is no recess in the seat cushion. An underlying air-ducting means  14  accordingly need not be pulled so deep into the trench  27 ′, or can even run horizontally over the area of the trench  27 ′ without any substantial deflection, embedding in foam or interruption. 
         [0024]    The tensioning device  40  preferably has at least one anchorage device  29  for attaching the cover  18 , by means of the tensioning device  40 , to the cushion or to corresponding fastening means  30 . It is preferable to provide at least two, better three, anchorage devices  29  per trench  27 ′. The anchorage device  29  may be configured as plastic profiles which then engage with corresponding fastening means  30  ( FIG. 3 ). They may also be configured as hooks, holes or eyes (e.g.  FIGS. 4 to 8 ), which then engage a matching hook on the cushion. 
         [0025]    The tensioning device  40  preferably includes at least one stiffening element  9 . This ensures the uniform distribution of tensile forces along the pulled-down cover  18 . It is preferably shaped and incorporated in such a way as not to be felt by the seat occupant. This can be achieved by using a stiffening element made at least partially of a flexible material and shaped to permit bending, e.g. by using a flat plastic strip as shown in  FIGS. 2 and 4 , which is positioned approximately parallel to the plane of the cover. Another alternative is to configure the stiffening element  9  as wire, as shown in  FIGS. 5 to 8 . The stiffening element  9  can then also be incorporated deeper down in the cushion, a distance away from the seat surface ( FIG. 6 ). 
         [0026]    The tensioning device  40  preferably includes a tension-transmission device  28 ,  28 ′ for transmitting tensile forces from at least one stiffening element  9  to at least one anchorage device  29 . This tension-transmission device  28  is preferably formed at least partially by a strip of non-woven or bonded fabric, for example, or another, preferably air-permeable, textile ( FIG. 2 ,  3 ,  7 ). In this case, the stiffening element(s)  9  and the anchorage device(s)  29  are arranged on opposing longitudinal edges of the tension-transmission means. 
         [0027]    Provision may also be made for the tension-transmission device  28  to have at least one tube-like anchorage tape, preferably a net-like structure, preferably a textile, preferably a braided tube. 
         [0028]    However, the tension-transmission means  28 ,  28 ′ can also be configured as a plastic strip or to resemble a panel ( FIG. 4 ), or it can be formed by part of the cover  18  itself. Another alternative is to configure the tension-transmission device  28 ′ as wire or as the wire section of a tensioning bow ( FIGS. 5 to 8 ). 
         [0029]    It is to advantage if the tensioning device  40  has at least two tension-transmission devices  28  which are spaced apart from each other and which connect the cover  18  with the rest of the seat  1110 , and that the area of the trench  27 ′ located between the tension-transmission devices  28  is at least partially open for the passage of air, and if the tensioning device  40  has at least two tension-transmission devices  28  which connect the cover  18  with the rest of the seat and that for at least part of the distance between these two tension-transmission devices  28  a flexible reinforcing strip acting as a stiffening element  9  is arranged at the cover  18  in order to ensure that the cover  18  sits uniformly along the length of the trench  27 ′. This arrangement makes it possible to transmit the tensile forces of the entire trench  27 ′ via two strands. As a result, the air-ducting layer to be spanned is compartmentalized only to a minimum extent, if at all. At the same time, the tensile force acting between the cover  18  and the cushion is substantially linear thanks to the stiffening elements  9  and the anchorage devices  29 . 
         [0030]    It is expedient if at least one tensioning device  40  has an air permeability of at least 1 m/s (as per German standard DIN 9237) in the transverse direction, that is, in the direction in which the air-ducting means  14  runs. 
         [0031]    The tensioning device  40  preferably has at least one pressure-distribution device  33  in order to distribute the pressure acting on the air-ducting layer or other functional elements beneath the cover over a larger area. This measure prevents localized concentration of pressure. A pressure-distribution device  33  of this kind can be made, for example, of felt upholstery tape, as shown in  FIG. 6 . 
       LIST OF REFERENCE NUMERALS 
       [0000]    
       
           1  Functional element in the seat 
           9  Stiffening element 
           14  Air-ducting means 
           18  Seat cover (e.g. of perforated leather/fabric) 
           18  Seat-cover backing (e.g. foam backing) 
           20  Recess in the cushion body (e.g. a channel in the foamed upholstery) 
           27 ′ Trench 
           28  Tension-transmission device (e.g. of nonwoven fabric) 
           29  Anchorage device (e.g. hog ring) 
           30  Fastening means (e.g. embedded in foam) 
           33  Pressure-distribution device 
           40  Tensioning device 
           50  Air-conditioned zone  1   
           52  Air-conditioned zone  2   
           100  Climate-conditioning system 
           110  Temperature-control means 
           120  Air-ducting means for the climate-conditioning system 
           130  Moisture-regulating means 
           400  Cushion 
           1000  Vehicle 
           1100  Interior fitting 
           1110  Seat