GB2037240A - A flap arrangement for an aircraft - Google Patents

Abstract

In a flap arrangement, for a wing 10 of an aircraft, which is actuated by a strut of a hydraulic cylinder, a spoiler (11) is coupled by way of push rods (17) and levers (18, 19) in such away to the trailing edge flap (12) that the spoiler (11) is locked in a closed position during flap deflections from +30 DEG to -30 DEG and is opened only during flap deflection from -30 DEG to -70 DEG in synchronism with the angle of the flap deflection. <IMAGE>

Description

SPECIFICATION A flap arrangement for an aircraft This invention relates to a flap arrangement, for a wing of an aircraft, which is actuated by a hydraulic cylinder.

Such arrangements are known in the most varied versions. Depending on the type of aircraft for which such known flat arrangements are used, they are often very expensive or complicated. Those arrangements described in German Auslegeschrift No. 21 25 971 and German Offenlegungsschrift No. 2047221 are particular examples. Undoubtedly these known arrangements have their merits and advantages, but they do require a relatively high expenditure on individual structural elements, their interconnections and the installation thereof.

Described in German Offenlegungsschrift No. 22 53877 is a slotted spoiler for an aileron arrangement in which the spoiler has a flat sawtoothed plate which is mounted adjacent the slot on the spoiler itself and which is intended to produce, in the case of a spoiler angle of incidence or attack of 0 , no unfavourable resistance and only in the case of a spoiler which is extended upwardly does it produce a vortex from the slot.

This arrangement, too, requires, for its function, at least two operating cylinders, one for the spoiler and one for the flap, since both parts are mounted separately from one another in openings in a wing.

The expenditure for the synchronisation of the movement of the two cylinders is just as high as that in the constructions discussed earlier.

An object of the present invention is to provide a flap arrangement which is simple in construction and arrangement and in which a flap and a ventilated spoiler are driven by a single cylinder.

Accordingly the invention provides a flat arrange mentforawing of an aircraft which is actuated buy a strut of a hydraulic cylinder, wherein a spoiler is coupled by way of a rod and levers in such a way to a flap that the spider is locked in a closed position during flap displacement from +30 to -30" and is opened, in the event of a flap deflection greater that -30" in synchronism with the angle of the flap deflection.

The invention will be described further, by way of example, with reference to the accompanying drawings, wherein: Figure 1 is a side view of a first preferred embodiment of flat arrangement of the invention; and Figure 2 is a similar view of a second preferred embodiment.

In a first preferred embodiment of arrangement of the invention (Figure 1), a spoiler 11 is connected by a pivotal joint 16to a rear edge of a wing 10. A rear edge of the spoiler 11 rests on a support for a pivotal joint 20 connected to a flap 12. On the flap 12 there is a plate 21 with which an extendable piston rod 14 of a hydraulic cylinder 13 engages. One end of an arm 22 is also pivotally connected to plate 21 and its other end is pivotally connected to a stop plate 19.

Arm 22 transmits pivotal movement of the flap 12 above a flap deflection of -30" to the spoiler 11. In the case of flap deflections from +30 to -30 , the spoiler 11 remains in the closed position.

This is achieved by the stop plate 19, which is arranged so as to be pivotable about an axis 19b, is provided with a slot 19a into which a locking bolt 19c on the spoiler 11 engages.

This slot 19a is curved in such a way that it can perform pivotal movement in response to flap movements ranging from +30 to -30 , without disengaging the locking bolt 19c.

If the flap deflection exceeds -30" the stop plate 19 disengages locking 19a, 19e and draws a connecting rod 17, to the right in the Figure. Rod 17 connects by way of a deflection lever 18 and a toggle joint 23 with the pivotal joint 16 of the spoiler 11. As rod 17 moves downwards and to the right, toggle joint 23 sets the spoiler in rotary motion in synchronism with the angle of deflection, i.e. the spoiler opens the air guide slot in synchronism with the movement of the flap 12.

Figure 1 shows in dotted lines the spoiler positions -corresponding to the flap deflections. The toggle joint 23 is connected by way of a swivel bolt or pin 18a to a metal fitting 15, which is connected securely towing 10.

As a result of this construction it is possible to transmit pivotal movements of the trailing edge flap over and above a set level to the spoiler and cause it to move in synchronism. The mechanism is simple and no additional hydraulic cylinder is necessary. In this wey, not only is the expenditure on component parts reduced, but also the constructioilitself is, from development, simple and uncomplicated. As a result of this construction, all the previously necessary synchronisation elements for two or more hydraulic cylinders and so forth are abolished. The fact that a not inconsiderable saving in weight has been made is an additional advantage.

Figure 2 shows a further exemplified embodiment of the invention in which the spoiler 11 is pivoted by means of a two-armed lever 24, one arm of which has a guide slot 25. In this embodiment, too, the spoiler remains closed and locked in all angular positions from +30 to -30". Only in the event of greater deflection than +30 does the lock automatically release and the spoiler become free to perform pivotal movement. Here the fitting 15 carries merely the hydraulic cylinder 13, whilst the lever 24 (which is connected to the spoiler via a hinge lever 23) is mounted for pivotal motion on a further support piece. Lever 23 connects to the spoiler 11 by a support piece 26.

Whilst the embodiment in accordance with Figure 1 has a very high reliability and pivotal accuracy, since only mechanical parts are used, in the case of the embodiment in accordance with Figure 2 a small loss of reliability is possible, since through the use of a slotted lever arm, necessarily a greater play occurs than is the case upon the use of bearings. Otherwise, however, also this embodiment has the same advantages as aforedescribed.

To be added to these advantages is additionally the simple and problemfree maintenance and the not inconsiderable saving in costs, without this entailing any impairment in respect of reliability and safety.

Claims (6)

1. A flap arrangement for a wing of an aircraft which is actuated by a strut of a hydraulic cylinder, wherein a spoiler is coupled by way of a rod and levers in such a way to a flap that the spoiler is locked in a closed position during flap displacement from +30 to -30 and is opened, in the event of a flap deflection greater than -30" in synchronism with the angle of the flap deflection.

2. A flap arrangement as claimed in claim 1, wherein the push rods and shift levers include a pivoted angled lever having a guide slot in one arm and a lever connecting the end of the other arm of the angled lever to the spoiler.

3. A flap arrangement as claimed in claim 1, wherein locking of the spoiler is affected by a pivotable member connected to the flap by a connecting rod having an arcuate slot engaging a bolt on the spoiler, which slot only disengages the bolt when the flap has pivoted more than -30".

4. Aflap arrangement as claimed in claim 3 wherein the pivotable member is connected to one end of said rod whose other end acts on a toggle joint connected to the spoiler.

5. A flap arrangement as claimed in claim 3 or 4, wherein the pivotable member is connected to an actuating plate of the flap (on which plate the hydraulic cylinder acts) by a connecting rod to pivoting of the flap.

6. Aflap arrangement from aircraft substantially as hereinbefore described with reference to and as illustrated in Figure 1 or 2 of the accompanying drawings.