Vehicle seat, especially aircraft passenger seat

A vehicle seat, especially an aircraft passenger seat, has at least one seat component which can be adjusted in its position, such as a seat part. The seat part can be mounted with its seat frame structure (3) by swivelable support legs (7, 11) above a floor structure (1). The support legs (7, 11) act on the seat frame structure (3) in pairs in the area of the front edge (9) and rear edge (5) of the seat of the seat part. An actuating mechanism is connected by action to a pair of support legs (7, 11) for producing a swiveling motion of the support legs (7, 11) causing a change in the position of the seat part. The actuating mechanism is coupled to the assigned pair of support legs (7, 11) by a differential mechanism (13) which converts the swiveling motion of the support legs (11) into a change of the effective length of the assigned pair of support legs (11). The length determines the vertical distance between the seat frame structure (3) and the floor structure (1).

FIELD OF THE INVENTION

The present invention relates to a vehicle seat, especially an aircraft passenger seat, with at least one seat component which can be adjusted in its position. A seat part can be mounted with its seat frame structure by swivelable support legs above a floor structure. The support legs act on the seat frame structure in pairs in the area of the front edge and rear edge of the seat of the seat part. An actuating mechanism, connected by action to a pair of support legs, produces a swiveling motion of the support legs causing a change in the position of the seat part.

BACKGROUND OF THE INVENTION

Vehicle seats are known with seat components which are adjustable in their position. Thus, for example, DE 101 07 197 A1 discloses a seat of this type in the form of an aircraft passenger seat.

In vehicles for commercial conveyance of passengers, specifically in commercial aviation aircraft, only a limited installation space is available for seating. In other words, especially for economic reasons, an especially compact construction of the seats is desired. On the other hand, high demands can be imposed on functionality and the comfort to be afforded the seat occupant, especially in aircraft passenger seats for business class or first class. With respect to these requirements, known seats have a plurality of control, actuating and adjustment mechanisms, resulting in a complex structure. In the limited space between the seat frame structure and the floor structure, very little free installation space is available. Therefore, it is difficult or impossible to freely choose the geometry of the pairs of support legs and/or the geometrical locations of their coupling points to the seat frame structure and the floor structure, such that the desired change in the position of the seat part occurs when swiveling motions of the pairs of support legs are caused by the actuating mechanism.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a vehicle seat which provides greater freedom of design in the configuration of the pairs of support legs, and, at the same time, provides adjustment of the position of the seat part in the desired manner.

This object is achieved according to the present invention by a vehicle seat having a differential mechanism which changes the effective length of an assigned pair of support legs depending on their swiveling motion. The length determines the vertical distance between the seat frame structure and the floor structure. Each adjustment of the position of the seat part desired can be achieved as a result of the swiveling motion of the support legs, without being tied to a certain geometry of the support legs or articulated connections. Greater freedom is provided with respect to the use of the limited free installation space available, because depending on circumstances the most favorable positional arrangement of the support legs can be selected.

In a seat in which the seat part can be adjusted between an initial position which is the rear position relative to the direction of travel and an end position which is displaced forward, by the differential mechanism, the effective length of the support pair connected to it can be matched to the effective length of the other support pair which can be changed when the position is adjusted. Without being tied to a certain geometry of the configuration and attachment of the support legs, this arrangement ensures that the entire adjustment motion of the seat part between the initial position and the end position takes place without any change of the tilt relative to the floor structure, i.e., over the entire adjustment path a horizontal position of the seat part is maintained.

The differential mechanism can be formed by a mechanical lever mechanism.

Preferably the lever mechanism for each support leg of the assigned pair has a bell crank lever. One lever arm of the lever mechanism is articulated to the end of the pertinent support leg, which end is adjacent to the floor structure. The other lever arm is articulated to the floor structure. In one preferred exemplary embodiment, the two bell crank levers are permanently connected for common motion with one another by a shaft extending through between the support legs from one bell crank lever to the other bell crank lever.

In these exemplary embodiments, the actuating mechanism can have a controllable power drive which acts on the shaft, and applies an actuating force with the bell crank levers which are connected to it. This force produces a torque for the swiveling motion of the bell crank levers around their coupling point to the floor structure. The controllable power drive can be a linear drive with a driving element, for example, in the manner of a piston rod, which is articulated at a distance from the axis of the shaft to a projection which extends away from the shaft.

In the exemplary embodiments in which an actuating force can be applied to the bell crank levers by the power drive of the actuating mechanism and causes a displacement motion of the seat part forward by the assigned pair of support legs, there is preferably a second power drive acting on the shaft with an opposing actuating force to apply a reset force to the bell crank levers. This reset force seeks to produce a displacement motion of the seat part backwards. Advantageously, the second power drive makes available an auxiliary force which, when the first power drive is deactivated or when the first power drive has failed, makes it possible for the seat part which has been pushed forward to be reset into the rear initial position by manual intervention without a greater expenditure of force being necessary for this purpose.

An energy accumulator, especially in the form of a pressurized spring, can be provided as the second power drive.

Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In the figures, the vehicle seat of the present invention is explained using one embodiment which is an aircraft passenger seat.FIG. 1shows only the floor structure1which is to be mounted above the cabin floor. The seat frame structure3is mounted above the floor structure. Pairs of support legs bear the seat frame structure3. For each pair of support legs, only the support leg facing the viewer being visible. The rear pair acts on the seat frame structure3on its back end area5and has a support leg7. The visible support leg11of the front pair acts on the front end area9of the seat frame structure. These front support legs11are each connected to the floor structure1by a bell crank lever13which is articulated to the leg and which forms an articulated lengthening of the respective support leg11, at a coupling point15. The support legs7of the rear pair are connected to the floor structure1at a coupling point17. The opposite, top ends of the support legs7and11are coupled to the seat frame structure3by coupling points19for the rear support legs7and by coupling points21for the front support legs11.

As can readily be seen from the figures, the arms23and25of the bell crank levers13are oriented at an obtuse angle relative one another, with the arm23forming the coupling point15for connection to the floor structure1on a shoulder27of the floor structure1. Shoulder27projects obliquely upward. The other, longer arm25of the bell crank levers13is connected by an articulation point29to the bottom end of the assigned support leg11. As can readily be seen fromFIG. 4, the two bell crank levers13are permanently or fixedly connected to one another for common motion by a shaft31. Shaft31extends through between the support legs11perpendicular to the plane of the drawing ofFIGS. 1 to 3, so that in these figures only the front end33can be seen.

As is most clearly shown inFIG. 4, the shaft31, between the bell crank levers13, has a projection35with an end area which forms an articulation point37for articulated connection to the piston rod-like driving element39of a controllable linear drive41. Activation of the linear drive41causes a retraction movement of the piston rod-like driving element39.FIG. 1, which shows the components in the rear initial position, illustrates the position of the articulation point37on which the driving element39of the power drive41, which is not shown inFIG. 1, acts in the position which corresponds to the fully extended position of the driving element39. When the power drive41is actuated, the retraction motion of the driving element39causes the articulation point37of the projection35of the shaft31to move out of the position shown inFIG. 1to the right. This movement causes rotary motion of the unit formed from the shaft31and the bell crank levers13clockwise around the coupling point15.

FIG. 2shows the middle position in which the driving element39of the linear drive41is partially retracted so that the bell crank levers13are swiveled slightly clockwise out of the position shown inFIG. 1. As a comparison ofFIGS. 1 and 2shows, the effective length of the front support legs11, i.e., the distance between the coupling point21to the seat frame structure3and the floor structure11, which distance is dictated by the support legs11, is increased slightly. At the same time, a displacement motion of the seat frame structure3forward (to the left in the drawings) has taken place, so that the rear support legs7have moved into a steeper position relative to the position inFIG. 1. The increase of the effective length of the support legs7resulting from the change of their position is equalized as a result of the aforementioned swiveling motion of the bell crank levers13. Specifically, the differential drive, which is formed by the bell crank levers13, has matched the effective lengths of the front support legs11and the rear support legs7to one another so that the displacement motion of the seat frame structure3has taken place without any tilt.

FIG. 3shows the components in the front end position, with the driving element39of the linear drive41being completely retracted. Thus, the shaft31with the bell crank lever13is swiveled further clockwise around the coupling point15. The resulting change in the position of the coupling point29on the arm25of the bell crank lever13causes a corresponding lengthening of the front support legs11for equalization of the other, in turn corresponding change of the effective length which resulted for the rear support legs7. Thus, due to the differential mechanism the entire displacement motion of the seat frame part3takes place without a change in tilt.

FIGS. 2 to 4show another shoulder43which is located next to the projection35on the shaft31. The push rod47of another or reset power drive in the form of a pressurized spring49is coupled to the end45of shoulder43. Push rod47applies an actuating force to the shaft31. This force opposes the actuating force generated by the linear drive41. The strength of this reset force or auxiliary force is chosen such that when the linear drive41is deactivated or has failed, the seat frame structure3, and thus the seat part, can be pushed manually back into the rear initial position without a greater expenditure of force being necessary for this purpose.

Use of the present invention for several seats located behind one another in a row, as a result of the horizontal adjustment geometry of the seat part in the forward position, it is possible to reach the rear area (seat back) of a seat or seat component, which rear area is located in the row in front. In this way, the operating elements located in that rear area can be used, such as, for example, folding table units, display units and the like. As has previously been disclosed, in the first class section, the seats are located at greater distances to one another in a longitudinal row. Without the solution of the present invention, the assignable operating units of the preceding seat could not be used. Furthermore, it is possible, for two vehicle seats which are located immediately adjacent to one another transversely to the indicated longitudinal row, to continuously adjust the respective adjacent seat parts horizontally against one another. A lateral offset is achieved such that seat occupants who are sitting next to one another enjoy increased freedom, especially with respect to the adjacent arm area.