GB2188094A

GB2188094A - Aircraft door

Info

Publication number: GB2188094A
Application number: GB08606839A
Authority: GB
Inventors: Vadim Viktorovich Barsukov; Boris Borisovich Soloviev; Stanislav Evgenievic Khoroshun; Alexei Ivanovich Vasiliev
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-04-07
Filing date: 1986-03-19
Publication date: 1987-09-23
Also published as: FR2596726A1; CS247986A1; CS255288B1; GB8606839D0; DE3612654A1

Abstract

An aircraft door comprises a panel (2) provided with top and a bottom retractable shields articulated thereto and mechanically connected for movement with a handle (12), the door has a crescent-shaped hinge (24) which is also mechanically connected for movement with the handle via a two-arm lever (29) whose pivot (30) is articulated to the panel (2). One of the arms of the lever (29) is connected, through a tie-rod (32), to the handle (12), while the other arm thereof is articulated to one of the ends of a link (34) whose other end is articulated to the hinge (24) substantially at the midpoint thereof. Handle movement retracts the top and bottom shields, and pivots the door about one hinge pivot (27), whereupon the door may be pivoted, through the door opening, about a further hinge pivot (25). <IMAGE>

Description

SPECIFICATION Door of an aircraft The present invention relates generally to aircraft engineering and more specifically to the door of an aircraft.

The invention can find application in compartments, wherein the inside gas pressure, e.g., air pressure exceeds the pressure of an ambient atmosphere.

The invention is most efficiently applicable in pressurized cabins, cockpits and compartments of aircraft.

When people are undersuch conditionsas, e.g., in the passenger cabin of an aircraft while in flight, there arises the problem of affording safety ofthe passengers, concerned with prevention of spontaneous door opening in the course offlight underthe action of an excess pressure (with respect to the ambient atmosphere) effective within the passenger cabin.

Most hazardous in this respect are outward-opening doors that might spontaneously open while in flight due to the failure ofthe door lock or on account of any negligence committed in locking the door before flight.

Thus, inward-opening doors are the most reliable ones. Such a doorfeatures its proper area largerthan the area of the opening to be closed by the door.

Should the locking device of such doors fail, the door is forced against the door opening frame by virtue of thepressureinsidethecabin,thusprovidingthe required air-tightness of the latter and safety forthe people therein.

However, such a door required an additional space inside the cabin or compartmentthat cannot be utilized for any other purpose, which in turn results in increased overall dimensions and mass of an aircraft.

The best solution of the problem resides in a door construction having the configuration variable in the course of locking/unlocking.

When closed such a door has its area largerthan the rear ofthe opening to be closed, whereas when unlocked the door area becomes smallerthan the area of the opening to be closed. This enables one to open the door outwards, thus bringing itfrom the cabin or compartment through the door opening.

One prior-art door of an aircraft is known (cf. US Patent No.3,647,169) to comprise a panel and a shield articulated thereto.

In addition, the door has a hinge which is fixed stationary, with one of its ends, to theframe ofthe fuselage door opening . The door hinge has a device for the door to move up or down with respect to the hinge.

The shield is situated above the door panel top edge and is mechanically associated with the handle located on the panel inside surface. It is along this kinematic chain that the shield istraversablefrom one of its extreme positions to the other. When in one of its extreme positions (closed) the shield adjoins tightly to the door panel top edge and to the upper edge of the fuselage door opening, thus locking the door in its opening. When in the other extreme position (open) the shield is located on the inner side ofthe door panel andpartly underneath the upper edge ofthefuselage door opening, which enables one to raise the door with respect to its hinge and to open it.

The door of an aircraft discussed above features a construction involving door configuration variable in the course of door locking/unlocking. When unlocked the door becomes less in height than the height ofthe opening to be closed, which isduetothefactthatthe shield is transferred inside the compartment or cabin.

This makes it possible to raise the door a little, by virtue ofthe deviceforthe doorto move up ordown, and to bring the dooroutwardsthrough the door opening.

As a result, the door in question needs no additional space insidethe compartment or cabin that cannot be utilized for other purposes.

However, the kinematic chain interconnecting the shield with the handle and the device forthe door up and down movementfeature sophisticated construction and incorporates a great many components which are labour-consuming in manufacture and operation, which adds to the mass ofthe door and renders it more complicated in operation and maintenance.

Known the present state of the art is one more door of an aircraft (cf. US Patent No. 3,051,280) having its configuration variable in the course of opening/ closing. This door of an aircraft opens outwards and comprises a panel and a top and a bottom shield articulated thereto. Both ofthe shields are mechanically associated with the handle and aretraversable, by virtue of said kinematic chain, from one extreme position to the other.

When in one of its extreme positions (closed) the top shield adjoins tightly the upper edge of the fuselage door opening, while the bottom shield adjoins tightly the lower edge ofthefuselage door opening. In such a position the door is higherthan the opening to be closed (i.e., the fuselage door opening).

When in the other extreme position (open) the shields are swung insidethe cabin or compartment.

As a result, the door height becomes smallerthan the height of the fuselage door opening, so thatthe door can be brought outwards through the door opening.

To bring the door outwards, use is made of a hinge which is in fact two parallel link mechanisms interconnected through shafts. Each ofthe mechanisms is held, with one of its sides, to the door opening frame, while the other side of the mechanism is fixed on the door panel. Thetop parallel link mechanism has curvilinear guides to determine the door path when being opened.

The door hinge is mechanically associated with the handle. The kinematic chain that effects said association includes a cam disk having curvilinear guides which serve for coordinating the motion ofthe shields with respect to the door panel, and the motion of the latter with reference to the door hinge.

When closed the door under consideration is higher than the opening to be closed, thus providing for air-tightness of the compartment and safetyforthe people therein.

When open the door height becomes less than the height ofthe opening to be closed, thus making it possible to open the dooroutwards by bringing it outsidethe compartmentthroughthe door opening.

As a result, such a door requires no additional space insidethe cabin orcompartmentthat cannot be utilized for other purposes.

However, the door hinge and the kinematic chains interconnecting the hinge with the handle feature a very sophisticated constuction and a great many of intricate components (over forty in number), such as curvilinear guides and cam disks.

Moreover, the parallel link mechanisms are labourconsuming in manufacture and too complicated in assembly and operation, since the curvilinear guides needs permanent care, cleaning and lubrication.

In addition, the parallel link mechanisms discontinuethe outer skin and the side profile ofthe door frame, thus affecting adversely the door strength and reliability, and renders the doors sealing more complicated. When opening the doorthe aforesaid mechanisms get partly exposed, which might result in injury to the attending personnel, or in getting foreign objects in the mechanism.

All the aforementioned disadvantageous result in an increased door mass and in adversed reliability and operational vonveniencethereof.

It is therefore a primary and essential object ofthe invention to provide a door of an aircraft featuring such a construction ofthe hinge and of its mechanical association with the handlethatwould enable reliable door locking while in flight, its convenient operation and maintenance and reduced mass.

Said object is accomplished bythe provision of a doorfor an aircraft, comprising a panel provided with a top and a bottom shield articulated thereto, said shields being mechanically associated with a handle, said door having a hinge which is also mechanically associated with the handle, wherein according to the invention,the hinge is crescent-shaped, and the kinematic chain that interlinks the hinge and the handle,incorporatesa leverwhosepivotisarticulated to the door panel, one ofthe lever arms is connected, through a tie-rod, to the handle, while the other lever arm is articulated to one end of a link, whose other end is articulated to the door hinge substantially at the midpointthereof.

The door proposed herein features a construction involving door configuration variable in the course of its closinglopening.

When in the closed position the top shield adjoins tightly the upper edge ofthefuselage door opening, whilethe bottom shield adjoinstightlythe lower edge ofthefuselage door opening. When in such a position the door is higherthan the opening to be closed, thus providingforthe required air-tightness of the cabin or compartment and safetyofthepeopletherein.

When the door is opened the shields are swung inside the cabin or compartment, and the door height becomes smallerthan the height ofthe opening to be closed. This makes it possible to open the door outwards by bringing it outside of the cabin or compartmentthrough the dooropening. As a result, the door ofthe invention needs no additional space inside the cabin or compartment that cannot be utilizedforother purposes.

Furthermore, simple construction ofthe door hinge and ofthe kinematic chain interconnecting the hingle with the handle twhich incorporates three compo nentsall in all),providesforreliabledoorlockingwhile in flight, its convenient operation and maintenance and lower mass.

It is expedientthat in the door of an aircraft, according to the present invention, the axes of the pivot pins interconnecting the link with the lever and the hinge, and of those interconnecting the levers with the door panel, should be collinearwhen the door is closed.

Such an arrangement of the axes of articulated joints providesforthe most reliable door locking while in flight.

For the sake of better illustration ofthe present invention given below are some specific embodi mentsthereofwith reference to the accompanying drawings, wherein: FIG. is a door of an aircraft as viewed from within of an aircraft, according to the invention; FIG. 2 is a section taken along the line ll-ll of FIG. 1; FIG. 3 is a section taken along the Ill-Ill of FIG. 1,with the door closed, according to the invention; FIG. 4 is substantially similarto FIG. 3 with thesole exception thatthe door is in the intermediate position, according to the invention; and FIG. 5 is substantially similarto FIG. 3 with the sole exception thatthe door is in the open position, according to the invention.

The doorofan aircraft is fitted in a frame 1 (Fig. 1) of the fuselage door opening. The door comprises a panel 2 with a top shield 3 and a bottom shield 4. The top shield3 is held to the panel 2through a pivot pin 5 (Fig. 2), while the bottom shield 4 is attached to the panel 2through a pivot pin 6.

The fuselage door opening frame 1 has a top edge 7 to which the top shield 3 adjoins when in the closed position, and a bottom edge 8to which the shield 4 adjoins when in the closed position.

A bracket 9 is provided in the middle of the top shield 3 (Fig. 1) on the inner side thereof, and a bracket 10 is provided in the middle of the bottom shield 4 on its inner side.

A plate 11 is fastened on the inner surface ofthe panel 2, said plate carrying a handle 12 with a shaft 13 (Fig. 2).Adouble-arm lever 14 is secured on the shaft 13, said lever being connected, through a tie-rod 15 (Fig. 1 )to a bell-crank 16which is mounted on a rod 17 fastened on the plate 11. The double-arm lever 14 is connected, via a tie-rod 18, a bell-crank 19 and a tie-rod 20, to the bracket 10 of the bottom shield 4. The bell-crank 16 is connected, through a tie-rod 21, a bell-crank 22 and a tie-rod 23, to the bracket 9of the top shield 3.

Thus, the shields 3 and 4 are mechanically associ ated with the handle 12. When the handle 12 isturned from the leftmost to the rightmost position, the top shield 3 and the bottom shield 4 rotate aboutthe pivot pin (Fig. 2) and the pivot pin 6, respectively, through appropriate angles, whereby the height ofthe door becomes sma[lerthan the height of the fuselage door openingframe 1, and two gapes having a clearance value of a are formed between the shields 3,4 and the top edge 7 and the bottom edge 8 ofthe frame 1.

The door of an aircraft has a hinge 24 (FIG. 3) which is crescent-shaped. The hinge 24 with one end of its crescent is connected, through a pivot 25, to a bracket 26 installed on a frame 1 of the fuselage door opening while with the other end of its crescentthe hinge 24 is connected, through pivots 27, to brackets 28 fixed stationary on a door panel 2.

The hinge 24 is mechanically associated with a handle 12.

The kinematic chain interconnecting the hinge 24 with the handle 12, comprises a double-arm lever 29 which is connected via a pivot pin 30, to a bracket 31 which in turn is fixed on the door panel 2. One ofthe arms ofthe lever 29 is articulated to a tie-rod 32 which is connected to a double-arm lever 14 (FIG. 1) set on a shaft 13 ofthe handle 12 (FIG. 3). The otherarm ofthe double-arm lever 29 is connected, through a pivot pin 33, to one ofthe ends of a link34, the other end of said link being connected, via a pivot pin 35, to a bracket 36 made fast on an inner surface 37 of the hinge 24 su bstantially atthe midpointthereof.

An adequately simple construction of the hinge 24 and ofthe kinematic chain interconnecting the hinge 24with the handle 12 providesfor reliable door locking while in flight and its convenient operation and maintenance. In addition, a total door mass is substantially reduced due to a few components incorporated in the aforesaid kinematic chain.

With the door closed the axes of the pivot pins 30,33 and 35 are collinear, which prevents the door from spontaneous rotation aboutthe pivots 27 with respect to the crescent-shaped hinge 24 and provides for the most reliable door locking while in flight.

Atthe same time the shape of the inner surface 37 of the crescent-shaped hinge 24 is such that it does not interfere with the door swinging aboutthe pivots 27 when opened bythe handle 12. An additional handle 38 is provided on the hinge 24to facilitate door opening and closing.

Two lock pins 39 (FIG.4) are provided on the side of the door panel 2 opposite to the hinge 24, which,when the door is closed, engage recesses 40 made in the fuselage door opening frame 1, thus preventing the door from rotating about the pivots 25.

A bracket 41 (Fig. 2) installed on the inner bottom portion ofthe door panel 2 and adapted to interact with a stop 42 provided on the frame 1, restricts the door inward motion when opened or closed.

The herein-proposed door of an aircraftfeatures the door configuration variable in the course of door opening/closing. When in the closed position (FIG. 3) the door is higherthan the fuselage door opening frame 1 and cannot therefore open outwards spontaneously, thus providing for the required air-tightness of the cabin or compartment and safety ofthe people therein.

While in flight the door is subjected to an excess pressure effective in the cabin or compartment, which prevents the door from spontaneously opening inward the aircraft.

When in the open position the door height becomes smallerthanthe height ofthe fuselage door opening frame bythe doubled amount of a clearance gap a (FIG. 2), which makes it possible to open the door by bringing it outside of the cabin or compartment through the door opening. AIl the aforementioned operations are carried out with the use of a minimized quantity ofthe components in the kinematic chain for door opening and closing.

The door opening occurs in the following sequence of operations.

The control handle 12 is turned clockwise from its Ieftmosttotherightmostposition.This makesthe shaft 13 carrying the double-arm lever 14 rotate along with the handle 12.

The bottom arm ofthe lever 14,while acting through bell-cranks 16,19,22 and tie-rods 15,18,20,21,23, causes the shields 3 and 4to turn about pivot pins 5 and 6.

Thereby the door height becomes smallerthan the height ofthe door opening by the doubled amount of the clearance gap a.

The top arm ofthe lever 14,while acting through the tie-rod 32, causes the double-arm lever 29 associated with the crescent-shaped hinge 24through the link 34, to turn round the pivot 30.

Thus the doorturns about the pivots 27 and moves inside the crescent-shaped hinge 24, whereby the lock pins 39 disengages the recesses 40. In such a position the door is brought outside the fuselage with the aid of the additional handle38byturningthedooraboutthe pivot 25 as shown in FIG. 5.

When closedthedoorisbrought,withthehelpof the handle 38, inside the fuselage until the bracket 41 thrusts againstthe stop 42. Then the handle 12 is rotated counterclockwise from the rightmost to the leftmost position. As a result, the doors runs with respect to the crescent-shaped hinge 24so as to close the door opening. The lock pins 39 reengage the recesses 40, and the shields 3 and 4 are pressed againstthetop edge 7 and the bottom edge 8 ofthe door opening frame 1 as shown in FIG. 3. It is the collinear arrangement ofthe axes of the pivot pins 30, 33,35 with the door closed that is in fact an additional safeguard against spontaneous door opening.

Claims

1. Adoorofan aircraft, comprising a panel provided with a top and a bottom shield articulated thereto, said shields being mechanically associated with a handle, said door having a hinge which is crescent-shaped and-is also mechanically associated with the handle through a lever whose pivot is articulated to the door panel, one ofthe lever arms is connected, through a tie-rod, to the handle, while the other lever arm is articulated to one of the ends of a link, whose other end is articulated to the door hinge substantiallyatthe midpoint thereof.

2. Adoorofan aircraft as claimed in Claim 1, wherein the axes of the pivot pins interconnecting the linkto the lever and the hinge, and of those inteconnecting the lever to the door panel, are collinear when the door is closed.

3. A door of an aircraft substantially as disclosed in a specific embodimentthereofwith reference to, and as iliustrated in the accompanying drawings.