The invention relates to a seat, especially an airplane or vehicle seat, with a seat part which is mounted upright on a seat structure relative to the floor and which is provided with a supporting part on its front.
Especially on very long passages, such as long-distance flights, but also on cruises, for example by means of ferries, a general object of the aircraft and ferry outfitters is to increase the comfort of seat occupants and accordingly of the passengers who are to be transported. Especially in first class and business class the customers have corresponding ideas about what they want, which wishes are to be satisfied. There is also a trend among passengers to be able to use the travel time for meaningful rest or sleeping, in order for example to effectively counteract jet lag at the destination for long-distance flights or the like.
DE 100 91 484 A1 discloses a vehicle seat, especially an aircraft passenger seat, with a seat part and backrest which are held to be able to move relative to one another by way of at least one adjustment device. In that, in the known solution, the respective adjustment device has several articulations which are connected to one another at least partially by way of a rod supporting framework as the seat structure, which bears the seat part and which executes traversing motion by an actuating means such that the seat part can be moved out of an initial position into other positions which are used for resting and sleeping and vice versa, depending on the number of attached articulations and rod parts of the rod supporting framework, the number of possibilities for movement and therefore the degrees of freedom of movement for the seat part are greatly increased compared to known solutions, so that positioning of the seat part and backrest is possible within very wide adjustment ranges. In that the known seat has pivoting leg and foot rests, the bottom of the leg area, especially the bottom of the thigh of the seat occupant, can be relieved, so that harmful pressure which reduces the cross section of the veins and thus the danger of thromboses are reduced. Based on the price structure of the pertinent seats and with respect to their space and weight requirement, they are used essentially only in first class and business class and cannot be easily used for economy class. Furthermore, with the known seat design, likewise the veins are exposed to strain, especially for the case in which the seat is in the upright (take-off position) and the leg and foot rests which relieve the cross sections of the veins folded down for the corresponding support and relief are then not available.
On the basis of this prior art, the object of the invention is to devise a seat, especially an aircraft or vehicle seat, which can be universally used and which does not have the described disadvantages in the prior art, especially helps avoid the danger of thromboses for long passages. This object is achieved by a seat with the features of claim 1 in its entirety.
In that, as specified in the characterizing part of claim 1, the supporting part is made flexible and at a definable seat load can be moved in the direction of the seat structure, and when unloaded moves back in the reverse direction away from the seat structure into its initial position, a seat is devised with a front area which is flexibly held, so that depending on the respective seat load applied by the seat occupant, the front area of the seat part yields and in this way reduces the compressive forces on the bottom of the thigh of the seat occupant, with the result that the cross sections of the veins in this area are not reduced, but their cross section is in turn maintained with the result that blood circulation is not disrupted and thus the risk of thrombosis is clearly reduced. With the solution as claimed in the invention a maximum support area of the thigh in any seat position is consequently achieved while avoiding compressive forces mainly in the forward area of the bottom of the thigh, and furthermore harmful shearing forces on the bottom of the thigh are also avoided. The pertinent shearing forces which are to be reduced arise especially in the area of the thigh in the reclining position compared to the upright seat position (take-off position) in which a more radically set seat angle is necessary. It is this greater seat angle which however causes an increase in the pressure on the bottom of the thigh when the legs are extended (slough position), with the already described danger of increasing the risk of thrombosis for the seat occupant. The occurrence of these shear forces is reliably avoided by the yielding capacity of the front area of the seat part.
The pertinent “healthy seat” can also be used in the area of motor vehicles, for example for busses; other applications are however conceivable in the area of medical treatment chairs, and in dentistry. Furthermore the comfort of the seat also increases for those seats which are equipped with pivoting leg and foot rests for relieving the bottom of the thigh. Comfort for these seats, certainly in the upright position, can also be further enhanced in this way.
In one preferred embodiment of the seat as claimed in the invention, the flexible supporting part is designed as a spiral spring which can be freely moved with one end and with its other end is fixed on elements of the seat part and/or of the support structure. If this spiral spring is designed as a rectangular leaf spring, this can be regarded as a loaded, free rest, the bending stress assuming its highest values at the bearing point and decreasing uniformly with increasing distance from the latter. Preferably the supporting part in its flexible configuration is made of a thermoplastic, but preferably of a fiber composite, especially a fiber composite fabric which is furthermore preferably an integral component of a seat shell which bears the foam cushion of the seat part and in this way also contributes to the comfort of sitting for the seat occupant.
Other advantageous embodiments are features of the other dependent claims.
The seat as claimed in the invention is detailed below using one embodiment as shown in the drawings in which in the form of diagrams and not drawn to scale:
The seat as claimed in the invention is configured especially as an aircraft seat, preferably a passenger seat. As shown in
The flexible supporting part 18 is designed as a spiral spring which can be freely moved with one end 20 and with its other end 22 can be fixed on elements of the remaining seat part 10, as is shown in the figures, and/or alternatively also on parts of the seat structure 12. Furthermore, to obtain the indicated bending or leaf spring characteristic, the supporting part 18 is designed as a flexible support plate and can consist for example of sheet metal material. For reasons of safety engineering and for reasons of saving weight, however the indicated support plate consists preferably of a thermoplastic material, its having been found to be especially advantageous to form the supporting part 18 from a fiber composite material, for example in the form of a fiber composite fabric of carbon fiber, kevlar, or the like. Metallic leaf spring parts can also be laminated into the fiber composite for support at the same time.
From the standpoint of production engineering it has proven especially advantageous to form the supporting part 18 as an integral component of the actual seat shell 24. This seat shell 24 is shown particularly in
In order to compensate in relative terms for the length between the foam cushion 28 and the seating part 18, in the area of the supporting part 18 the foam cushion 28 merely rests there and is otherwise held in the seat shell 24. On the opposite side of the overlap of the foam cushion 28 on the supporting part 18, with the corresponding force loading (force arrow F) it can be supported with its bottom on the top of a support site, formed by the transversely extending front support member 14. The indicated support site can be formed, in contrast to the drawing in
Furthermore, seen in the direction of looking at
The seat structure 12 furthermore has a rear support member 16 which likewise extends transversely to the seat part 10 along its back end, by way of this additional support member 16 the seat part 10 being securely connected to the seat structure 12. But if for the seat adjustment motion what is desired is that the seat part 10 moves in relative terms against the stationary seat structure 12 with its two support members 14, 16, by way of a corresponding lateral guide (not shown) this can likewise be achieved without adversely affecting the function of the resilient supporting part 18. As
The flexible front edge of the seat as claimed in the invention has the advantage that accordingly with a relatively small foam thickness of the foam body 28 which promotes a reduction of weight, a high degree of adaptation to the seat occupant is ensured. Due to the flexible yielding capacity of the supporting part 18 shearing forces in the area of the thigh are also greatly reduced in the reclining seat position and otherwise the cross sections of the veins are relieved accordingly so that the risk of thrombosis drops distinctly.
Number | Date | Country | Kind |
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103 08 454.1 | Feb 2003 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP04/00821 | 1/30/2004 | WO | 9/27/2006 |